Thermochemical nitrate destruction
Cox, John L.; Hallen, Richard T.; Lilga, Michael A.
1992-01-01
A method is disclosed for denitrification of nitrates and nitrates present in aqueous waste streams. The method comprises the steps of (1) identifying the concentration nitrates and nitrites present in a waste stream, (2) causing formate to be present in the waste stream, (3) heating the mixture to a predetermined reaction temperature from about 200.degree. C. to about 600.degree. C., and (4) holding the mixture and accumulating products at heated and pressurized conditions for a residence time, thereby resulting in nitrogen and carbon dioxide gas, and hydroxides, and reducing the level of nitrates and nitrites to below drinking water standards.
Thermochemical nitrate destruction
Cox, J.L.; Hallen, R.T.; Lilga, M.A.
1992-06-02
A method is disclosed for denitrification of nitrates and nitrites present in aqueous waste streams. The method comprises the steps of (1) identifying the concentration nitrates and nitrites present in a waste stream, (2) causing formate to be present in the waste stream, (3) heating the mixture to a predetermined reaction temperature from about 200 C to about 600 C, and (4) holding the mixture and accumulating products at heated and pressurized conditions for a residence time, thereby resulting in nitrogen and carbon dioxide gas, and hydroxides, and reducing the level of nitrates and nitrites to below drinking water standards.
Engineering Options Assessment Report. Nitrate Salt Waste Stream Processing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anast, Kurt Roy
2015-11-13
This report examines and assesses the available systems and facilities considered for carrying out remediation activities on remediated nitrate salt (RNS) and unremediated nitrate salt (UNS) waste containers at Los Alamos National Laboratory (LANL). The assessment includes a review of the waste streams consisting of 60 RNS, 29 above-ground UNS, and 79 candidate below-ground UNS containers that may need remediation. The waste stream characteristics were examined along with the proposed treatment options identified in the Options Assessment Report . Two primary approaches were identified in the five candidate treatment options discussed in the Options Assessment Report: zeolite blending and cementation.more » Systems that could be used at LANL were examined for housing processing operations to remediate the RNS and UNS containers and for their viability to provide repackaging support for remaining LANL legacy waste.« less
Engineering Options Assessment Report: Nitrate Salt Waste Stream Processing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anast, Kurt Roy
2015-11-18
This report examines and assesses the available systems and facilities considered for carrying out remediation activities on remediated nitrate salt (RNS) and unremediated nitrate salt (UNS) waste containers at Los Alamos National Laboratory (LANL). The assessment includes a review of the waste streams consisting of 60 RNS, 29 aboveground UNS, and 79 candidate belowground UNS containers that may need remediation. The waste stream characteristics were examined along with the proposed treatment options identified in the Options Assessment Report . Two primary approaches were identified in the five candidate treatment options discussed in the Options Assessment Report: zeolite blending and cementation.more » Systems that could be used at LANL were examined for housing processing operations to remediate the RNS and UNS containers and for their viability to provide repackaging support for remaining LANL legacy waste.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weisbrod, Kirk Ryan; Veirs, Douglas Kirk; Funk, David John
This report describes the derivation of the salt composition from the Veazey salt stream analysis. It also provides an estimate of the proportions of the kitty litter, nitrate salt and neutralizer that was contained in drum 68660. While the actinide content of waste streams was judiciously followed in the 1980s in TA-55, no record of the salt composition could be found. Consequently, a salt waste stream produced from 1992 to 1994 and reported by Gerry Veazey provided the basis for this study. While chemical analysis of the waste stream was highly variable, an average analysis provided input to the Streammore » Analyzer software to calculate a composition for a concentrated solid nitrate salt and liquid waste stream. The calculation predicted the gas / condensed phase compositions as well as solid salt / saturated liquid compositions. The derived composition provides an estimate of the nitrate feedstream to WIPP for which kinetic measurements can be made. The ratio of salt to Swheat in drum 68660 contents was estimated through an overall mass balance on the parent and sibling drums. The RTR video provided independent confirmation concerning the volume of the mixture. The solid salt layer contains the majority of the salt at a ratio with Swheat that potentially could become exothermic.« less
Use of an Artificial Sweetener to Identify Sources of Groundwater Nitrate Contamination.
Robertson, W D; Van Stempvoort, D R; Roy, J W; Brown, S J; Spoelstra, J; Schiff, S L; Rudolph, D R; Danielescu, S; Graham, G
2016-07-01
The artificial sweetener acesulfame (ACE) is a potentially useful tracer of waste water contamination in groundwater. In this study, ACE concentrations were measured in waste water and impacted groundwater at 12 septic system sites in Ontario, Canada. All samples of septic tank effluent (n = 37) had ACE >6 µg/L, all samples of groundwater from the proximal plume zones (n = 93) had ACE >1 µg/L and, almost all samples from the distal plume zones had ACE >2 µg/L. Mean mass ratios of total inorganic nitrogen/ACE at the 12 sites ranged from 680 to 3500 for the tank and proximal plume samples. At five sites, decreasing ratio values in the distal zones indicated nitrogen attenuation. These ratios were applied to three aquifers in Canada that are nitrate-stressed and an urban stream where septic systems are present nearby to estimate the amount of waste water nitrate contamination. At the three aquifer locations that are agricultural, low ACE values (<0.02-0.15 µg/L) indicated that waste water contributed <15% of the nitrate in most samples. In groundwater discharging to the urban stream, much higher ACE values (0.2-11 µg/L) indicated that waste water was the likely source of >50% of the nitrate in most samples. This study confirms that ACE is a powerful tracer and demonstrates its use as a diagnostic tool for establishing whether waste water is a significant contributor to groundwater contamination or not. © 2016, National Ground Water Association.
NASA Astrophysics Data System (ADS)
Kreitler, Charles W.; Browning, Lawrence A.
1983-02-01
Results of nitrogen-isotope analyses of nitrate in the waters of the Cretaceous Edwards aquifer in Texas, U.S.A., indicate that the source of the nitrate is naturally-occurring nitrogen compounds in the recharge streams. In contrast, nitrogen isotopes of nitrate in the fresh waters of the Pleistocene Ironshore Formation on Grand Cayman Island, West Indies, indicate that human wastes are the source of the nitrate. The Cretaceous Edwards Limestone is a prolific aquifer that produces principally from fracture porosity along the Balcones Fault Zone. Recharge is primarily by streams crossing the fault zone. Rainfall is ˜ 70 cm yr. -1, and the water table is generally deeper than 30 m below land surface. The δ15 N of 73 samples of nitrate from Edwards waters ranged from + 1.9 to + 10‰ with an average of + 6.2‰. This δ15 N range is within the range of nitrate in surface water in the recharge streams ( δ 15N range = + 1 to + 8.3‰ ) and within the range of nitrate in surface water from the Colorado River, Texas, ( δ 15N range = + 1 to + 11‰ ). No sample was found to be enriched in 15N, which would suggest the presence of nitrate from animal waste ( δ 15N range = + 10 to + 22‰ ). The Ironshore Formation contains a small freshwater lens that is recharged entirely by percolation through the soil. Average rainfall is 165 cm yr. -1, and the water table is within 3 m of land surface. The δ15 N of four nitrate samples from water samples of the Ironshore Formation ranged from + 18 to + 23.9‰, which indicates a cesspool/septictank source of the nitrate. Limestone aquifers in humid environments that are recharged by percolation through the soil appear to be more susceptible to contamination by septic tanks than are aquifers in subhumid environments that feature thick unsaturated sections and are recharged by streams.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anast, Kurt Roy; Funk, David John
The inadvertent creation of transuranic waste carrying hazardous waste codes D001 and D002 requires the treatment of the material to eliminate the hazardous characteristics and allow its eventual shipment and disposal at the Waste Isolation Pilot Plant (WIPP). This report documents the effectiveness of two treatment methods proposed to stabilize both the unremediated and remediated nitrate salt waste streams (UNS and RNS, respectively). The two technologies include the addition of zeolite (with and without the addition of water as a processing aid) and cementation. Surrogates were developed to evaluate both the solid and liquid fractions expected from parent waste containers,more » and both the solid and liquid fractions were tested. Both technologies are shown to be effective at eliminating the characteristic of ignitability (D001), and the addition of zeolite was determined to be effective at eliminating corrosivity (D002), with the preferred option1 of zeolite addition currently planned for implementation at the Waste Characterization, Reduction, and Repackaging Facility. During the course of this work, we established the need to evaluate and demonstrate the effectiveness of the proposed remedy for debris material, if required. The evaluation determined that Wypalls absorbed with saturated nitrate salt solutions exhibit the ignitability characteristic (all other expected debris is not classified as ignitable). Follow-on studies will be developed to demonstrate the effectiveness of stabilization for ignitable Wypall debris. Finally, liquid surrogates containing saturated nitrate salts did not exhibit the characteristic of ignitability in their pure form (those neutralized with Kolorsafe and mixed with sWheat did exhibit D001). As a result, additional nitrate salt solutions (those exhibiting the oxidizer characteristic) will be tested to demonstrate the effectiveness of the remedy.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaminski, Michael D.; Mertz, Carol J.
2016-01-01
The physical properties of a surrogate waste form containing cesium, strontium, rubidium, and barium sintered into bentonite clay were evaluated for several simulant feed streams: chlorinated cobalt dicarbollide/polyethylene glycol (CCD-PEG) strip solution, nitrate salt, and chloride salt feeds. We sintered bentonite clay samples with a loading of 30 mass% of cesium, strontium, rubidium, and barium to a density of approximately 3 g/cm 3. Sintering temperatures of up to 1000°C did not result in volatility of cesium. Instead, there was an increase in crystallinity of the waste form upon sintering to 1000ºC for chloride- and nitrate-salt loaded clays. The nitrate saltmore » feed produced various cesium pollucite phases, while the chloride salt feed did not produce these familiar phases. In fact, many of the x-ray diffraction peaks could not be matched to known phases. Assemblages of silicates were formed that incorporated the Sr, Rb, and Ba ions. Gas evolution during sintering to 1000°C was significant (35% weight loss for the CCD-PEG waste-loaded clay), with significant water being evolved at approximately 600°C.« less
Engineered Option Treatment of Remediated Nitrate Salts: Surrogate Batch-Blending Testing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anast, Kurt Roy
2016-03-11
This report provides results from batch-blending test work for remediated nitrate salt (RNS) treatment. Batch blending was identified as a preferred option for blending RNS and unremediated nitrate salt (UNS) material with zeolite to effectively safe the salt/Swheat material identified as ignitable (U.S. Environmental Protection Agency code D001). Blending with zeolite was the preferred remediation option identified in the Options Assessment Report and was originally proposed as the best option for remediation by Clark and Funk in their report, Chemical Reactivity and Recommended Remediation Strategy for Los Alamos Remediated Nitrate Salt (RNS) Wastes, and also found to be a preferredmore » option in the Engineering Options Assessment Report: Nitrate Salt Waste Stream Processing. This test work evaluated equipment and recipe alternatives to achieve effective blending of surrogate waste with zeolite.« less
NASA Technical Reports Server (NTRS)
Lunn, Griffin Michael; Spencer, LaShelle E.; Ruby, Anna Maria; McCaskill, Andrew
2014-01-01
Current International Space Station water recovery regimes produce a sizable portion of waste water brine. This brine is highly toxic and water recovery is poor: a highly wasteful proposition. With new biological techniques that do not require waste water chemical pretreatment, the resulting brine would be chromium-free and nitrate rich which can allow possible fertilizer recovery for future plant systems. Using a system of ion exchange resins we can remove hardness, sulfate, phosphate and nitrate from these brines to leave only sodium and potassium chloride. At this point modern chlor-alkali cells can be utilized to produce a low salt stream as well as an acid and base stream. The first stream can be used to gain higher water recovery through recycle to the water separation stage while the last two streams can be used to regenerate the ion exchange beds used here, as well as other ion exchange beds in the ISS. Conveniently these waste products from ion exchange regeneration would be suitable as plant fertilizer. In this report we go over the performance of state of the art resins designed for high selectivity of target ions under brine conditions. Using ersatz ISS waste water we can evaluate the performance of specific resins and calculate mass balances to determine resin effectiveness and process viability. If this system is feasible then we will be one step closer to closed loop environmental control and life support systems (ECLSS) for current or future applications.
Lumetta, Gregg J; Braley, Jenifer C; Peterson, James M; Bryan, Samuel A; Levitskaia, Tatiana G
2012-06-05
Removing phosphate from alkaline high-level waste sludges at the Department of Energy's Hanford Site in Washington State is necessary to increase the waste loading in the borosilicate glass waste form that will be used to immobilize the highly radioactive fraction of these wastes. We are developing a process which first leaches phosphate from the high-level waste solids with aqueous sodium hydroxide, and then isolates the phosphate by precipitation with calcium oxide. Tests with actual tank waste confirmed that this process is an effective method of phosphate removal from the sludge and offers an additional option for managing the phosphorus in the Hanford tank waste solids. The presence of vibrationally active species, such as nitrate and phosphate ions, in the tank waste processing streams makes the phosphate removal process an ideal candidate for monitoring by Raman or infrared spectroscopic means. As a proof-of-principle demonstration, Raman and Fourier transform infrared (FTIR) spectra were acquired for all phases during a test of the process with actual tank waste. Quantitative determination of phosphate, nitrate, and sulfate in the liquid phases was achieved by Raman spectroscopy, demonstrating the applicability of Raman spectroscopy for the monitoring of these species in the tank waste process streams.
Process for Nitrogen Oxide Waste Conversion to Fertilizer
NASA Technical Reports Server (NTRS)
Lueck, Dale E. (Inventor); Parrish, Clyde F. (Inventor)
2003-01-01
The present invention describes a process for converting vapor streams from sources containing at least one nitrogen-containing oxidizing agent therein to a liquid fertilizer composition comprising the steps of: a) directing a vapor stream containing at least one nitrogen-containing oxidizing agent to a first contact zone; b) contacting said vapor stream with water to form nitrogen oxide(s) from said at least one nitrogen-containing oxidizing agent; c) directing said acid(s) as a second stream to a second contact zone; d) exposing said second stream to hydrogen peroxide which is present within said second contact zone in a relative amount of at least 0.1% by weight of said second stream within said second contact zone to convert at least some of any nitrogen oxide species or ions other than in the nitrate form present within said second stream to nitrate ion; e) sampling said stream within said second contact zone to determine the relative amount of hydrogen peroxide within said second contact zone; f) adding hydrogen peroxide to said second contact zone when a level of hydrogen peroxide less than 0.1 % by weight in said second stream is determined by said sampling; g) adding a solution comprising potassium hydroxide to said second stream to maintain a pH between 6.0 and 11.0 within said second stream within said second contact zone to form a solution of potassium nitrate; and h) removing said solution of potassium nitrate from said second contact zone.
Wastes and by-products - alternatives for agricultural use
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boles, J.L.; Craft, D.J.; Parker, B.R.
1994-10-01
Top address a growing national problem with generation of wastes and by-products, TVA has been involved for several years with developing and commercializing environmentally responsible practices for eliminating, minimizing, or utilizing various wastes/by-products. In many cases, reducing waste generation is impractical, but the wastes/by-products can be converted into other environmentally sound products. In some instances, conversion of safe, value-added agricultural products in the best or only practical alternative. TVA is currently involved with a diversity of projects converting wastes/by-products into safe, economical, and agriculturally beneficial products. Environmental improvement projects have involved poultry litter, cellulosic wastes, used battery acid, ammonium sulfatemore » fines, lead smelting effluents, deep-welled sulfuric acid/ammonium bisulfate solutions, wood ash, waste magnesium ammonium sulfate slurry from recording tape production, and ammunition plant waste sodium nitrate/ammonium nitrate streams.« less
Hazards Associated with Legacy Nitrate Salt Waste Drums Managed under the Container Isolation Plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Funk, David John; Clark, David Lewis
At present, there are 29 drums of nitrate waste salts (oxidizers with potentially acidic liquid bearing RCRA characteristics D001 and D002) that are awaiting processing, specifically to eliminate these characteristics and to allow for ultimate disposition at WIPP. As a result of the Feb. 14th, 2014 drum breach at WIPP, and the subsequent identification of the breached drum as a product ofLANL TRU waste disposition on May 15th, 2014, these 29 containers were moved into the Perrnacon in Dome 231 at TA-54 Area G, as part of the New Mexico Environment Department (NMED) approved container isolation plan. The plan ismore » designed to mitigate hazards associated with the nitrate salt bearing waste stream. The purpose of this document is to articulate the hazards associated with un-remediated nitrate salts while in storage at LANL. These hazards are distinctly different from the Swheat-remediated nitrate salt bearing drums, and this document is intended to support the request to remove the un-remediated drums from management under the container isolation plan. Plans to remediate and/or treat both of these waste types are being developed separately, and are beyond the scope of this document.« less
Process and Equipment for Nitrogen Oxide Waste Conversion to Fertilizer
NASA Technical Reports Server (NTRS)
Lueck, Dale E. (Inventor); Parrish, Clyde F. (Inventor)
2000-01-01
The present invention describes a process for converting vapor streams from sources containing at least one nitrogen-containing oxidizing agent therein to a liquid fertilizer composition comprising the steps of: (1) directing a vapor stream containing at least nitrogen-containing oxidizing agent to a first contact zone; (2) contacting said vapor stream with water to form nitrogen oxide(s) from said at least one nitrogen- containing oxidizing agent; (3) directing said acid(s) as a second stream to a second contact zone; (4) exposing said second stream to hydrogen peroxide which is present within said second contact zone in a relative amount of at least 0.1% by weight of said second stream within said second contact zone to convert at least some of any nitrogen oxide species or ions other than in the nitrite form present within said second stream to nitrate ion; (5) sampling said stream within said second contact zone to determine the relative amount of hydrogen peroxide within said second contact zone; (6) adding hydrogen peroxide to said second contact zone when a level on hydrogen peroxide less than 0.1% by weight in said second stream is determined by said sampling; (7) adding a solution comprising potassium hydroxide to said second stream to maintain a pH between 6.0 and 11.0 within said second stream within said second contact zone to form a solution of potassium nitrate; and (8) removing sais solution of potassium nitrate from said second contact zone.
Season matters when sampling streams for swine CAFO waste pollution impacts.
Mallin, Michael A; McIver, Matthew R
2018-02-01
Concentrated (or confined) animal feed operations (CAFOs) are the principal means of livestock production in the United States, and such facilities pollute nearby waterways because of their waste management practices; CAFO waste is pumped from the confinement structure into a cesspit and sprayed on a field. Stocking Head Creek is located in eastern North Carolina, a state with >9,000,000 head of swine confined in CAFOs. This watershed contains 40 swine CAFOs; stream water quality was investigated at seven sites during 2016, with five sampling dates in early spring and five in summer. Geometric mean fecal coliform counts were in the thousands/100 mL at five sites in spring and all seven sites in summer. Excessive nitrate pollution was widespread with concentrations up to >11.0 mg N/L. Seasonality played an important role in pollutant concentrations. In North Carolina, spraying animal waste on adjoining fields is permissible from March 1 through September 30. Seasonal data showed significantly higher (p < 0.01) concentrations of conductivity, nitrate, total nitrogen, total organic carbon, and fecal bacteria in summer as opposed to early spring. Thus, sampling performed only in winter-early spring would significantly underestimate impacts from swine CAFO spray fields on nearby waterways.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Funk, David John
2016-05-05
The sampling of unremediated nitrate salts (UNS) was originally proposed by the U.S. Department of Energy (DOE) and Los Alamos National Security, LLC (LANS) (collectively, the Permittees) as a means to ensure adequate understanding and characterization of the problematic waste stream created when the Permittees remediated these nitrate salts-bearing waste with an organic absorbent. The proposal to sample the UNS was driven by a lack of understanding with respect to the radioactive contamination release that occurred within the underground repository at the Waste Isolation Pilot Plant (WIPP) in February 14, 2014, as well as recommendations made by a Peer Reviewmore » Team. As discussed, the Permittees believe that current knowledge and understanding of the waste has sufficiently matured such that this additional sampling is not required. Perhaps more importantly, the risk of both chemical and radiological exposure to the workers sampling the UNS drum material is unwarranted. This memo provides the technical justification and rationale for excluding the UNS sampling from the treatment studies.« less
Fida, Tekle Tafese; Gassara, Fatma; Voordouw, Gerrit
2017-07-15
Amendment of reservoir fluid with injected substrates can enhance the growth and activity of microbes. The present study used isopropyl alcohol (IPA) or acetone to enhance the indigenous anaerobic nitrate-reducing bacterium Thauera sp. TK001. The strain was able to grow on IPA or acetone and nitrate. To monitor effects of strain TK001 on oil recovery, sand-packed columns containing heavy oil were flooded with minimal medium at atmospheric or high (400psi) pressure. Bioreactors were then inoculated with 0.5 pore volume (PV) of minimal medium containing Thauera sp. TK001 with 25mM of acetone or 22.2mM of IPA with or without 80mM nitrate. Incubation without flow for two weeks and subsequent injection with minimal medium gave an additional 17.0±6.7% of residual oil in place (ROIP) from low-pressure bioreactors and an additional 18.3% of ROIP from the high-pressure bioreactors. These results indicate that acetone or IPA, which are commonly used organic solvents, are good substrates for nitrate-mediated microbial enhanced oil recovery (MEOR), comparable to glucose, acetate or molasses, tested previously. This technology may be used for coupling biodegradation of IPA and/or acetone in waste streams to MEOR where these waste streams are generated in close proximity to an oil field. Copyright © 2017 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Conrad, Mark; Bill, Markus
2008-08-01
The nitrogen ({delta}{sup 15}N) and oxygen ({delta}{sup 18}O) isotopic compositions of nitrate in the environment are primarily a function of the source of the nitrate. The ranges of isotopic compositions for nitrate resulting from common sources are outlined in Figure 1 from Kendall (1998). As noted on Figure 1, processes such as microbial metabolism can modify the isotopic compositions of the nitrate, but the effects of these processes are generally predictable. At Hanford, nitrate and other nitrogenous compounds were significant components of most of the chemical processes used at the site. Most of the oxygen in nitrate chemicals (e.g., nitricmore » acid) is derived from atmospheric oxygen, giving it a significantly higher {delta}{sup 18}O value (+23.5{per_thousand}) than naturally occurring nitrate that obtains most of its oxygen from water (the {delta}{sup 18}O of Hanford groundwater ranges from -14{per_thousand} to -18{per_thousand}). This makes it possible to differentiate nitrate from Hanford site activities from background nitrate at the site (including most fertilizers that might have been used prior to the Department of Energy plutonium production activities at the site). In addition, the extreme thermal and chemical conditions that occurred during some of the waste processing procedures and subsequent waste storage in select single-shell tanks resulted in unique nitrate isotopic compositions that can be used to identify those waste streams in soil and groundwater at the site (Singleton et al., 2005; Christensen et al., 2007). This report presents nitrate isotope data for soil and groundwater samples from the Hanford 200 Areas and discusses the implications of that data for potential sources of groundwater contamination.« less
Wieben, Christine M.; Baker, Ronald J.; Nicholson, Robert S.
2013-01-01
Five streams in the Barnegat Bay-Little Egg Harbor (BB-LEH) watershed in southern New Jersey were sampled for nutrient concentrations and stable isotope composition under base-flow and stormflow conditions, and during the growing and nongrowing seasons, to help quantify and identify sources of nutrient loading. Samples were analyzed for concentrations of total nitrogen, ammonia, nitrate plus nitrite, organic nitrogen, total phosphorus, and orthophosphate, and for nitrogen and oxygen stable isotope ratios. Concentrations of total nitrogen in the five streams appear to be related to land use, such that streams in subbasins characterized by extensive urban development (and historical agricultural land use)—North Branch Metedeconk and Toms Rivers—exhibited the highest total nitrogen concentrations (0.84–1.36 milligrams per liter (mg/L) in base flow). Base-flow total nitrogen concentrations in these two streams were dominated by nitrate; nitrate concentrations decreased during storm events as a result of dilution by storm runoff. The two streams in subbasins with the least development—Cedar Creek and Westecunk Creek—exhibited the lowest total nitrogen concentrations (0.16–0.26 mg/L in base flow), with organic nitrogen as the dominant species in both base flow and stormflow. A large proportion of these subbasins lies within forested parts of the Pinelands Area, indicating the likelihood of natural inputs of organic nitrogen to the streams that increase during periods of storm runoff. Base-flow total nitrogen concentrations in Mill Creek, in a moderately developed basin, were 0.43 to 0.62 mg/L and were dominated by ammonia, likely associated with leachate from a landfill located upstream. Total phosphorus and orthophosphate were not found at detectable concentrations in most of the surface-water samples, with the exception of samples collected from the North Branch Metedeconk River, where concentrations ranged from 0.02 to 0.09 mg/L for total phosphorus and 0.008 to 0.011 mg/L for orthophosphate. Measurements of nitrogen and oxygen stable isotope ratios of nitrate in surface-water samples revealed that a mixture of multiple subsurface sources, which may include some combination of animal and septic waste, soil nitrogen, and commercial fertilizers, likely contribute to the base-flow nitrogen load. The results also indicate that atmospheric deposition is not a predominant source of nitrogen transported to the BB-LEH estuary from the watershed, although the contribution of nitrate from the atmosphere increases during stormflow. Atmospheric deposition of nitrate has a greater influence in the less developed subbasins within the BB-LEH watershed, likely because few other major sources of nitrogen (animal and septic waste, fertilizers) are present in the less developed subbasins. Atmospheric sources appear to contribute proportionally less of the overall nitrate as development increases within the BB-LEH watershed. Groundwater samples collected from five wells located within the BB-LEH watershed and screened in the unconfined Kirkwood-Cohansey aquifer system were analyzed for nutrient and stable isotope composition. Concentrations of nitrate ranged from not detected to 3.63 mg/L, with the higher concentrations occurring in the highly developed northern portion of the watershed, indicating the likelihood of anthropogenic sources of nitrogen. Isotope data for the two wells with the highest nitrate concentrations are more consistent with fertilizer sources than with animal or septic waste. Total phosphorus was not detected in any of the wells sampled, and orthophosphate was either not detected or measured at very low concentrations (0.005–0.009 mg/L) in each of the wells sampled.
Characteristics of water quality and streamflow, Passaic River basin above Little Falls, New Jersey
Anderson, Peter W.; Faust, Samuel Denton
1973-01-01
The findings of a problem-oriented river-system investigation of the water-quality and streamflow characteristics of the Passaic River above Little Falls, N.J. (drainage area 762 sq mi) are described. Information on streamflow duration, time-of-travel measurements, and analyses of chemical, biochemical, and physical water quality are summarized. This information is used to define relations between water quality, streamflow, geology, and environmental development in the basin's hydrologic system. The existence, nature, and magnitude of long-term trends in stream quality--as measured by dissolved solids, chloride, dissolved oxygen, biochemical oxygen demand, ammonia, nitrate, and turbidity--and in streamflow toward either improvement or deterioration are appraised at selected sites within the river system. The quality of streams in the upper Passaic River basin in northeastern New Jersey is shown to be deteriorating with time. For example, biochemical oxygen demand, an indirect measure of organic matter in a stream, is increasing at most stream-quality sampling sites. Similarly, the dissolved-solids content, a measure of inorganic matter, also is increasing. These observations suggest that the Passaic River system is being used more and more as a medium for the disposal of industrial and municipal waste waters. Dissolved oxygen, an essential ingredient for the natural purification of streams receiving waste discharges, is undersaturated (that is, below theoretical solubility levels) at all sampling sites and is decreasing with time at most sites. This is another indication of the general deterioration of stream quality in the upper basin. It also indicates that the ability of the river system to receive, transport, and assimilate wastes, although exceeded now only for short periods during the summer months, may be exceeded more continually in the future if present trends hold. Decreasing ratios of ammonia to nitrate in a downstream direction on the main stem Passaic River suggests that nitrification (the biochemical conversion of ammonia to nitrate) as well as microbiological decomposition of organic matter (waste waters) is contributing to the continued and increasing undersaturation of dissolved oxygen in the river system. Passaic River streams are grouped into five general regions of isochemical quality on the basis of predominant constituents and dissolved-solids content during low flows. The predominant cations in all but one region are calcium and magnesium (exceeding 50 percent of total cations) ; in that region, where man's activities probably have altered the natural stream waters, the percentage of sodium and potassium equals that of calcium and magnesium. In two of the five regions, the predominant anion is bicarbonate; a combination of sulfate, chloride, and nitrate is predominant in the other three regions. Dissolved-solids content during low flows generally ranges from 100 to 600 milligrams per liter. Several time-of-travel measurements within the basin are reported. These data provide reasonable estimates of the time required for soluble contaminants to pass through particular parts of the river system. For example, the peak concentration of a contaminant injected into the river system at Chatham during extreme low flow would be expected to travel to Little Falls, about 31 miles, in about 13 days; but at medium flow, in about 5 days.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anast, Kurt Roy; Funk, David John; Hargis, Kenneth Marshall
The inadvertent creation of transuranic waste carrying hazardous waste codes D001 and D002 requires the treatment of the material to eliminate the hazardous characteristics and allow its eventual shipment and disposal at the Waste Isolation Pilot Plant (WIPP). This report documents the effectiveness of two treatment methods proposed to stabilize both the unremediated and remediated nitrate salt waste streams (UNS and RNS, respectively) at Los Alamos National Laboratory (LANL). The two technologies include the addition of zeolite (with and without the addition of water as a processing aid) and cementation. Surrogates were developed to evaluate both the solid and liquidmore » fractions expected from parent waste containers, and both the solid and liquid fractions were tested. Both technologies are shown to be effective at eliminating the characteristic of ignitability (D001), and the addition of zeolite was determined to be effective at eliminating corrosivity (D002), with the preferred option1 of adding zeolite currently planned for implementation at LANL’s Waste Characterization, Reduction, and Repackaging Facility (WCRRF). The course of this work verified the need to evaluate and demonstrate the effectiveness of the proposed remedy for debris material, if required. The evaluation determined that WypAlls, cheesecloth, and Celotex absorbed with saturated nitrate salt solutions exhibit the ignitability characteristic (all other expected debris is not classified as ignitable). Finally, liquid surrogates containing saturated nitrate salts did not exhibit the characteristic of ignitability in their pure form (those neutralized with Kolorsafe and mixed with sWheat did exhibit D001). Sensitivity testing and an analysis were conducted to evaluate the waste form for reactivity. Tests included subjecting surrogate material to mechanical impact, friction, electrostatic discharge and thermal insults. The testing confirmed that the waste does not exhibit the characteristic of reactivity (D003). Follow-on testing was conducted to demonstrate the effectiveness of zeolite stabilization for ignitable WypAll and cheesecloth debris and additional nitrate salt solutions (those exhibiting the oxidizer characteristic) to demonstrate the effectiveness of the remedy. Follow-on testing also included testing of surrogate materials containing Waste Lock 770, which is present in four of the RNS containers, and potential items of debris such as plywood and Celotex material. Testing to evaluate the effectiveness of the remedy was performed using the specific remediation processes that are planned for use at the WCRRF. Finally, testing was also performed to evaluate the holding capacity of zeolite using a highly acidic surrogate solution and to characterize the composition of gases generated during mixing of zeolite with surrogate solutions. All these tests demonstrated the effectiveness of adding zeolite as the planned remedy.« less
NASA Astrophysics Data System (ADS)
Sikora, M. T.; Elliott, E. M.
2009-12-01
Excess nitrate (NO3-) contributes to the overall degraded quality of streams in many urban areas. These systems are often dominated by impervious surfaces and storm sewers that can route atmospherically deposited nitrogen, from both wet and dry deposition, to waterways. Moreover, in densely populated watersheds there is the potential for interaction between urban waterways and sewer systems. The affects of accumulated nitrate in riverine and estuary systems include low dissolved oxygen, loss of species diversity, increased mortality of aquatic species, and general eutrophication of the waterbody. However, the dynamics of nitrate pollution from each source and it’s affect on urban waterways is poorly constrained. The isotopes of nitrogen and oxygen in nitrate have been proven effective in helping to distinguish contamination sources to ground and surface waters. In order to improve our understanding of urban nitrate pollution sources and dynamics, we examined nitrate isotopes (δ15N and δ18O) in base- and stormflow samples collected over a two-year period from a restored urban stream in Pittsburgh, Pennsylvania (USA). Nine Mile Run drains a 1,600 hectare urban watershed characterized by 38% impervious surface cover. Prior work has documented high nitrate export from the watershed (~19 kg NO3- ha-1 yr-1). Potential nitrate sources to the watershed include observed sewer overflows draining directly to the stream, as well as atmospheric deposition (~23 kg NO3- ha-1 yr-1). In this and other urban systems with high percentages of impervious surfaces, there is likely minimal input from nitrate derived from soil or fertilizer. In this presentation, we examine spatial and temporal patterns in nitrate isotopic composition collected at five locations along Nine Mile Run characterized by both sanitary and combined-sewer cross-connections. Preliminary isotopic analysis of low-flow winter streamwater samples suggest nitrate export from Nine Mile Run is primarily influenced by inputs of human waste despite high rates of atmospheric nitrate deposition. Further isotopic analysis of nitrate will examine seasonal variations in nitrate sources; compare nitrate dynamics and sources during low- versus high-flows, and the influence of interannual climatic variability on nitrate export.
MECHANISMS OF INORGANIC PARTICLE FORMATION DURING SUSPENSION HEATING OF SIMULATED AQEOUS WASTES
The paper gives results of measurements of metal partitioning between the fine condensation aerosol and the larger particles produced during rapid heating of polydisperse droplet streams of aqueous solutions containing nitrates of Cd, Pb, and Ni in a laboratory scale furnace. rim...
Mahler, Barbara J.; Musgrove, MaryLynn; Herrington, Chris; Sample, Thomas L.
2011-01-01
During 2008–10, the U.S. Geological Survey, in cooperation with the City of Austin, the City of Dripping Springs, the Barton Springs/Edwards Aquifer Conservation District, the Lower Colorado River Authority, Hays County, and Travis County, collected and analyzed water samples from five streams (Barton, Williamson, Slaughter, Bear, and Onion Creeks), two groundwater wells (Marbridge well [YD–58–50–704] and Buda well [LR–58–58–403]), and the main orifice of Barton Springs in Austin, Texas, with the objective of characterizing concentrations and isotopic compositions of nitrate and concentrations of wastewater compounds in the Barton Springs zone. The Barton Springs zone is in south-central Texas, an area undergoing rapid growth in population and in land area affected by development, with associated increases in wastewater generation. Over a period of 17 months, during which the hydrologic conditions transitioned from dry to wet, samples were collected routinely from the streams, wells, and spring and, in response to storms, from the streams and spring; some or all samples were analyzed for nitrate, nitrogen and oxygen isotopes of nitrate, and wastewater compounds. The median nitrate concentrations in routine samples from all sites were higher in samples collected during the wet period than in samples collected during the dry period, with the greatest difference for stream samples (0.05 milligram per liter during the dry period to 0.96 milligram per liter for the wet period). Nitrate concentrations in recent (2008–10) samples were elevated relative to concentrations in historical (1990–2008) samples from streams and from Barton Springs under medium- and high-flow conditions. Recent nitrate concentrations were higher than historical concentrations at the Marbridge well but the reverse was true at the Buda well. The elevated concentrations likely are related to the cessation of dry conditions coupled with increased nitrogen loading in the contributing watersheds. An isotopic composition of nitrate (delta nitrogen–15) greater than 8 per mil in many of the samples indicated there was a contribution of nitrate with a biogenic (human and or animal waste, or both) origin. Wastewater compounds measured in routine samples were detected infrequently (3 percent of cases), and concentrations were very low (less than the method reporting level in most cases). There was no correlation between nitrate concentrations and the frequency of detection of wastewater compounds, indicating that wastewater compounds might be undergoing removal during such processes as infiltration through soil. Three potential sources of biogenic nitrate to the contributing zone were considered: septic systems, land application of treated wastewater, and domesticated dogs and cats. During 2001–10, the estimated densities of septic systems and domesticated dogs and cats (number per acre) increased in the watersheds of all five creeks, and the rate of land application of treated wastewater (gallons per day per acre) increased in the watersheds of Barton, Bear, and Onion Creeks. Considering the timing and location of the increases in the three sources, septic systems were considered a likely source of increased nitrate to Bear Creek; land application of treated wastewater a likely source to Barton, Bear, and Onion Creeks; and domestic dogs and cats a potential source principally to Williamson Creek. The results of this investigation indicate that baseline water quality, in terms of nitrate, has shifted upward between 2001 and 2010, even without any direct discharges of treated wastewater to the creeks.
2012-03-01
approximately 2,300 curies of 137Cs (CsCl), and 1.5 tons of Ammonium nitrate / Fuel oil (ANFO). The explosive and the shielded CsCl sources are packaged into...previous findings. Experts also presented case studies on Hurricane Katrina, The British Petroleum (BP) Oil Spill, Fukushima Japan, Foot and Mouth...containers, conduct environmental monitoring. The waste streams were very organized into distinct categories. 1) oil , gasoline, pesticides, 2) batteries
Water Quality in Courtland Creek, East Oakland, California
NASA Astrophysics Data System (ADS)
Bracho, H.; Ahumada, A.; Hernandez, G.; Quintero, D.; Ramirez, J.; Ramirez, L.; Pham, T.; Holt, J.; Johnson, A.; Rubio, E.; Ponce, X.; Medina, S.; Limon, S.
2013-12-01
Courtland Creek is a tributary of the larger East Creek system that runs southeast from the Oakland Hills down to the San Leandro Bay in Oakland, California. In an effort to assess the overall health of Courtland Creek our team conducted a water quality research study. Stream water samples were collected from 4 sites between MacArthur Avenue (describe geographically as not all readers are familiar with Oakland geography) and Thompson Avenue (describe geographically as not all readers are familiar with Oakland geography) at accessible sections of this largely culverted stream. Dissolved oxygen, ammonia, nitrite, nitrate, phosphate, and chlorine concentrations in were measured using wet chemistry procedures. Analysis of collected samples indicates that dissolved oxygen levels in the stream are sufficient for invertebrates, ranging from 5 and 9 parts per million (ppm). Nitrate levels were significantly high, with concentrations ranging from 15 and 40 ppm. Other chemical species associated with waste products--ammonia, nitrite, and phosphate--also were present, but at low concentrations. Small amounts of chlorine also were found in waters of the creek system. The presence of high concentrations of nitrate, together with chlorine, suggests that untreated sewage may be leaking into Courtland Creek at an unidentified location.
RESULTS OF INITIAL AMMONIA OXIDATION TESTING
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nash, C.; Fowley, M.
This memo presents an experimental survey of aqueous phase chemical processes to remove aqueous ammonia from waste process streams. Ammonia is generated in both the current Hanford waste flowsheet and in future waste processing. Much ammonia will be generated in the Low Activity Waste (LAW) melters.i Testing with simulants in glass melters at Catholic University has demonstrated the significant ammonia production.ii The primary reaction there is the reducing action of sugar on nitrate in the melter cold cap. Ammonia has been found to be a problem in secondary waste stabilization. Ammonia vapors are noxious and destruction of ammonia could reducemore » hazards to waste treatment process personnel. It is easily evolved especially when ammonia-bearing solutions are adjusted to high pH.« less
Bader, M S H
2005-05-20
A novel hybrid system combining liquid-phase precipitation (LPP) and membrane distillation (MD) is integrated for the treatment of the INEEL sodium-bearing liquid waste. The integrated system provides a "full separation" approach that consists of three main processing stages. The first stage is focused on the separation and recovery of nitric acid from the bulk of the waste stream using vacuum membrane distillation (VMD). In the second stage, polyvalent cations (mainly TRU elements and their fission products except cesium along with aluminum and other toxic metals) are separated from the bulk of monovalent anions and cations (dominantly sodium nitrate) by a front-end LPP. In the third stage, MD is used first to concentrate sodium nitrate to near saturation followed by a rear-end LPP to precipitate and separate sodium nitrate along with the remaining minor species from the bulk of the aqueous phase. The LPP-MD hybrid system uses a small amount of an additive and energy to carry out the treatment, addresses multiple critical species, extracts an economic value from some of waste species, generates minimal waste with suitable disposal paths, and offers rapid deployment. As such, the LPP-MD could be a valuable tool for multiple needs across the DOE complex where no effective or economic alternatives are available.
Source Areas of Water and Nitrate in a Peatland Catchment, Minnesota, USA
NASA Astrophysics Data System (ADS)
Sebestyen, S. D.
2017-12-01
In nitrogen polluted forests, stream nitrate concentrations increase and some unprocessed atmospheric nitrate may be transported to streams during stormflow events. This understanding has emerged from forests with upland mineral soils. In contrast, catchments with northern peatlands may have both upland soils and lowlands with deep organic soils, each with unique effects on nitrate transport and processing. While annual budgets show nitrate yields to be relatively lower from peatland than upland-dominated catchments, little is known about particular runoff events when stream nitrate concentrations have been higher (despite long periods with little or no nitrate in outlet streams) or the reasons why. I used site knowledge and expansive/extensive monitoring at the Marcell Experimental Forest in Minnesota, along with a targeted 2-year study to determine landscape areas, water sources, and nitrate sources that affected stream nitrate variation in a peatland catchment. I combined streamflow, upland runoff, snow amount, and frost depth data from long-term monitoring with nitrate concentration, yield, and isotopic data to show that up to 65% of stream nitrate during snowmelt of 2009 and 2010 was unprocessed atmospheric nitrate. Up to 46% of subsurface runoff from upland soils during 2009 was unprocessed atmospheric nitrate, which shows the uplands to be a stream nitrate source during 2009, but not during 2010 when upland runoff concentrations were below the detection limit. Differences are attributable to variations in water and nitrate sources. Little snow (a nitrate source), less upland runoff relative to peatland runoff, and deeper soil frost in the peatland caused a relatively larger input of nitrate from the uplands to the stream during 2009 and the peatland to the stream during 2010. Despite the near-absence of stream nitrate during much of rest of the year, these findings show an important time when nitrate transport affected downstream aquatic ecosystems, reasons why nitrate was transported, and that atmospheric nitrate pollution had a direct effect on a stream in a peatland catchment. Furthermore, this work illustrates how long-term monitoring when coupled with shorter-duration studies allows contemporary questions to be addressed within legacy catchment studies.
Miller, Matthew P.; Tesoriero, Anthony J.; Capel, Paul D.; Pellerin, Brian A.; Hyer, Kenneth E.; Burns, Douglas A.
2016-01-01
We describe a new approach that couples hydrograph separation with high-frequency nitrate data to quantify time-variable groundwater and runoff loading of nitrate to streams, and the net in-stream fate of nitrate at the watershed-scale. The approach was applied at three sites spanning gradients in watershed size and land use in the Chesapeake Bay watershed. Results indicate that 58-73% of the annual nitrate load to the streams was groundwater-discharged nitrate. Average annual first order nitrate loss rate constants (k) were similar to those reported in both modelling and in-stream process-based studies, and were greater at the small streams (0.06 and 0.22 d-1) than at the large river (0.05 d-1), but 11% of the annual loads were retained/lost in the small streams, compared with 23% in the large river. Larger streambed area to water volume ratios in small streams result in greater loss rates, but shorter residence times in small streams result in a smaller fraction of nitrate loads being removed than in larger streams. A seasonal evaluation of k values suggests that nitrate was retained/lost at varying rates during the growing season. Consistent with previous studies, streamflow and nitrate concentration were inversely related to k. This new approach for interpreting high-frequency nitrate data and the associated findings furthers our ability to understand, predict, and mitigate nitrate impacts on streams and receiving waters by providing insights into temporal nitrate dynamics that would be difficult to obtain using traditional field-based studies.
Alexander, Richard B.; Böhlke, John Karl; Boyer, Elizabeth W.; David, Mark B.; Harvey, Judson W.; Mulholland, Patrick J.; Seitzinger, Sybil P.; Tobias, Craig R.; Tonitto, Christina; Wollheim, Wilfred M.
2009-01-01
The importance of lotic systems as sinks for nitrogen inputs is well recognized. A fraction of nitrogen in streamflow is removed to the atmosphere via denitrification with the remainder exported in streamflow as nitrogen loads. At the watershed scale, there is a keen interest in understanding the factors that control the fate of nitrogen throughout the stream channel network, with particular attention to the processes that deliver large nitrogen loads to sensitive coastal ecosystems. We use a dynamic stream transport model to assess biogeochemical (nitrate loadings, concentration, temperature) and hydrological (discharge, depth, velocity) effects on reach-scale denitrification and nitrate removal in the river networks of two watersheds having widely differing levels of nitrate enrichment but nearly identical discharges. Stream denitrification is estimated by regression as a nonlinear function of nitrate concentration, streamflow, and temperature, using more than 300 published measurements from a variety of US streams. These relations are used in the stream transport model to characterize nitrate dynamics related to denitrification at a monthly time scale in the stream reaches of the two watersheds. Results indicate that the nitrate removal efficiency of streams, as measured by the percentage of the stream nitrate flux removed via denitrification per unit length of channel, is appreciably reduced during months with high discharge and nitrate flux and increases during months of low-discharge and flux. Biogeochemical factors, including land use, nitrate inputs, and stream concentrations, are a major control on reach-scale denitrification, evidenced by the disproportionately lower nitrate removal efficiency in streams of the highly nitrate-enriched watershed as compared with that in similarly sized streams in the less nitrate-enriched watershed. Sensitivity analyses reveal that these important biogeochemical factors and physical hydrological factors contribute nearly equally to seasonal and stream-size related variations in the percentage of the stream nitrate flux removed in each watershed.
An unexpected truth: increasing nitrate loading can decrease nitrate export from watersheds
NASA Astrophysics Data System (ADS)
Askarizadeh Bardsiri, A.; Grant, S. B.; Rippy, M.
2015-12-01
The discharge of anthropogenic nitrate (e.g., from partially treated sewage, return flows from agricultural irrigation, and runoff from animal feeding operations) to streams can negatively impact both human and ecosystem health. Managing these many point and non-point sources to achieve some specific end-point—for example, reducing the annual mass of nitrate exported from a watershed—can be a challenge, particularly in rapidly growing urban areas. Adding to this complexity is the fact that streams are not inert: they too can add or remove nitrate through assimilation (e.g., by stream-associated plants and animals) and microbially-mediated biogeochemical reactions that occur in streambed sediments (e.g., respiration, ammonification, nitrification, denitrification). By coupling a previously published correlation for in-stream processing of nitrate [Mulholland et al., Nature, 2008, 452, 202-205] with a stream network model of the Jacksons Creek watershed (Victoria, Australia) I demonstrate that managing anthropogenic sources of stream nitrate without consideration of in-stream processing can result in a number of non-intuitive "surprises"; for example, wastewater effluent discharges that increase nitrate loading but decrease in-stream nitrate concentrations can reduce the mass of nitrate exported from a watershed.
Effects of Atmospheric Nitrate on an Upland Stream of the Northeastern USA
NASA Astrophysics Data System (ADS)
Sebestyen, S. D.; Shanley, J. B.; Boyer, E. W.; Kendall, C.
2009-05-01
Excess nitrogen cascades through terrestrial biogeochemical cycles and affects stream nitrate concentrations in upland forests where atmospheric deposition is an important source of anthropogenic nitrogen. We will discuss approaches including high-frequency sampling, isotopic tracers, and end-member mixing analysis that can be used to decipher the sources, transformations, and hydrological processes that affect nitrate transport through forested upland catchments to streams. We present results of studies at the Sleepers River Research Watershed in Vermont, USA, a site where we have intensively measured stream nitrate concentrations during baseflow and stormflow. Stream nitrate concentrations are typically low and nearly 75% of annual inorganic N inputs from atmospheric deposition are retained within the catchment. However, high concentrations and stream loadings of nitrate occur during storm events due to source variation and hydrological flushing of nitrate from catchment soils. Using isotopic tracers and end-member mixing analysis, we have quantified source inputs of unprocessed atmospheric nitrate and show that this stream is directly affected by nitrogen pollution. Using a long-term record of stream hydrochemistry and our findings on event- scale nitrate flushing dynamics, we then explore how stream nitrate loading may respond to anthropogenic climate forcing during the next century. Results suggest that stream runoff and nitrate loadings will change during future emission scenarios (i.e. longer growing seasons and higher winter precipitation rates). Understanding the timing and magnitude of hydrological and hydrochemical responses is important because climate change effects on catchment hydrology may alter how nitrate is retained, produced, and hydrologically flushed in headwater ecosystems with implications for aquatic metabolism, nutrient export from catchments, and downstream eutrophication.
Water quality assessment in streams and wastewater treatment plants of Blantyre, Malawi
NASA Astrophysics Data System (ADS)
Sajidu, S. M. I.; Masamba, W. R. L.; Henry, E. M. T.; Kuyeli, S. M.
The population of the city of Blantyre has grown rapidly over the past few years without keeping pace with the national economy. The most visibly affected areas of this increase in population are access to adequate clean water, solid waste collection and disposal, sanitary and sewerage facilities. The objective of this study was to evaluate water quality in streams and wastewater treatment plants (WWTP) in the City of Blantyre, Malawi. Study locations included Limbe WWTP, Soche WWTP, Limbe, Mudi and Nasolo streams. Water samples were collected by grab sampling technique in February 2005. Phosphates, nitrates and sulphates were determined by vanadomolybdophosphoric acid colorimetric, salicylate colorimetric and turbidimetric methods, respectively. Metals were analysed using atomic absorption spectroscopy. Concentrations of lead, cadmium, iron, manganese, zinc, chromium and nickel were much higher than the World Health safe limits for drinking water in all the sampled streams after they had passed through industrial areas. Nitrates and sulphates concentrations at all sampling points were found to be lower than the safe limits for drinking water of 50 mg/l and 250 mg/l, respectively. However, phosphate concentrations were above the safe limit of 0.5 mg/l. It was also observed that biochemical oxygen demand (BOD 5) levels were above the World Health Organisation limit of 20 mg/l at all sites except Mudi and Limbe streams before passing through industrial areas. This was an indication of pollution in the streams. Values of pH and total dissolved solids (TDS) were within the recommended standards. The results suggest that streams in Blantyre City get polluted by heavy metals and nutrients which could be due to uncontrolled industrial waste disposal, vehicular emissions and agricultural activities. Regular monitoring of the water quality and enforcement of environmental protection laws are needed in order to control pollution in the city.
Rodríguez-Martínez, Jesús; Guzmán-Ríos, Senén
2017-06-26
A study was conducted in 2014–15 by the U.S. Geological Survey (USGS), in cooperation with the Municipality of Caguas, to determine if changes in the stream sanitary quality during base-flow conditions have occurred since 1997–99, when a similar study was completed by the USGS. Water samples were collected for the current study during two synoptic surveys in 2014 and 2015. Water samples were analyzed for fecal and total coliform bacteria, nitrate plus nitrite as nitrogen, nitrogen and oxygen isotopes of nitrate, and human health and pharmaceutical products. Water sampling occurred at 39 stream locations used during the 1997–99 study by the USGS and at 11 additional sites. A total of 151 stream miles were classified on the basis of fecal and total coliform bacteria results.The overall spatial pattern of the sanitary quality of surface water during 2014–15 is similar to the pattern observed in 1997–99 in relation to the standards adopted by the Puerto Rico Environmental Quality Board in 1990. Surface water at most of the water-sampling sites exceeded the current standard for fecal coliform of 200 colonies per 100 milliliters adopted by the Puerto Rico Environmental Quality Board in 2010. The poorest sanitary quality was within the urban area of the Municipality of Caguas, particularly in urban stream reaches of Río Caguitas and in rural and suburban reaches bordered by houses in high density that either have inadequate septic tanks or discharge domestic wastewater directly into the stream channels. The best sanitary quality occurred in areas having little or no human development, such as in the wards of San Salvador and Beatriz to the south and southwest of Caguas, respectively. The concentration of nitrate plus nitrite as nitrogen ranged from 0.02 to 9.0 milligrams per liter, and did not exceed the U.S. Environmental Protection Agency drinking-water standard for nitrate as nitrogen of 10 milligrams per liter. The composition of nitrogen and oxygen isotopes of nitrate indicates that the origin of nitrate in the streams is most likely animal and human waste. A baseline was established for the concentrations of selected human health and pharmaceutical products at stations in some of the streams within the Municipality of Caguas. Thirty-eight human health and pharmaceutical products were present at or above the measurement detection level.
NASA Astrophysics Data System (ADS)
Kent, R. H.; Burton, C. A.
2001-12-01
This study examined the extent and variabiltity of nitrate loss in a 2.85 km reach of Cucamonga Creek, which is concrete-lined and dominated by treated municipal waste-water. Primary production was measured to determine if the loss could be attributed to algal assimilation. Samples for nitrite plus nitrate analysis were collected at the top and bottom of the study reach every hour throughout the 24-hour sampling period; samples for analyses of other parameters were collected less frequently. Water temperature, dissolved oxygen (DO), pH and specific conductance were monitored continuously throughout the sampling period using in-stream probes. During the two weeks prior to the study, periphyton samples were collected periodically at four stations along the reach for standing crop measurements and a growth rate time-series using Chlorophyll A and ash-free-dry mass. Water samples from the upstream station were compared to those taken an hour later (the approximate travel time) at the downstream station. Nitrate concentrations were lower at the downstream station in 21 of 25 of the paired samples, indicating nearly continuous loss in the reach. The total loss of NO3 for the day was about 0.71 g as N/m2. Most of the loss occurred during daylight hours, with the peak occurring at midday. During the night, CO2 concentrations were relatively constant at about 25 mg/L. Concentrations began to decline at sunrise, and declined to 0 mg/L at the lower site after midday. Peak nitrate loss occurred at about the same time as the CO2 concentration was at its minimum. DO declined slightly during the night, began to rise at sunrise, reached a peak during midday, and declined in late afternoon through evening; pH followed a similar pattern. Net primary productivity, as measured by the differences in DO between the two sites was 13 g O2/m2 for the day. Using the Redfield ratio, the predicted nitrate assimilation is about 0.66 g NO3 as N/m2. The continuous loss of nitrate between the two sites; the comparability between the observed loss in nitrate and that predicted using the Redfield ratio; and the timing of changes in nitrate loss, DO, pH and CO2 indicate that nitrate loss in this concrete-lined channel was primarily due to algal assimilation. The timing of the peak nitrate loss relative to the depletion of CO2 suggests that CO2 may be limiting photosynthesis, and therefore assimilation of nitrate by algae.
Sebestyen, Stephen D.; Shanley, James B.; Boyer, Elizabeth W.; Kendall, Carol; Doctor, Daniel H.
2014-01-01
Autumn is a season of dynamic change in forest streams of the northeastern United States due to effects of leaf fall on both hydrology and biogeochemistry. Few studies have explored how interactions of biogeochemical transformations, various nitrogen sources, and catchment flow paths affect stream nitrogen variation during autumn. To provide more information on this critical period, we studied (1) the timing, duration, and magnitude of changes to stream nitrate, dissolved organic nitrogen (DON), and ammonium concentrations; (2) changes in nitrate sources and cycling; and (3) source areas of the landscape that most influence stream nitrogen. We collected samples at higher temporal resolution for a longer duration than typical studies of stream nitrogen during autumn. This sampling scheme encompassed the patterns and extremes that occurred during base flow and stormflow events of autumn. Base flow nitrate concentrations decreased by an order of magnitude from 5.4 to 0.7 µmol L−1 during the week when most leaves fell from deciduous trees. Changes to rates of biogeochemical transformations during autumn base flow explained the low nitrate concentrations; in-stream transformations retained up to 72% of the nitrate that entered a stream reach. A decrease of in-stream nitrification coupled with heterotrophic nitrate cycling were primary factors in the seasonal nitrate decline. The period of low nitrate concentrations ended with a storm event in which stream nitrate concentrations increased by 25-fold. In the ensuing weeks, peak stormflow nitrate concentrations progressively decreased over closely spaced, yet similarly sized events. Most stormflow nitrate originated from nitrification in near-stream areas with occasional, large inputs of unprocessed atmospheric nitrate, which has rarely been reported for nonsnowmelt events. A maximum input of 33% unprocessed atmospheric nitrate to the stream occurred during one event. Large inputs of unprocessed atmospheric nitrate show direct and rapid effects on forest streams that may be widespread, although undocumented, throughout nitrogen-polluted temperate forests. In contrast to a week-long nitrate decline during peak autumn litterfall, base flow DON concentrations increased after leaf fall and remained high for 2 months. Dissolved organic nitrogen was hydrologically flushed to the stream from riparian soils during stormflow. In contrast to distinct seasonal changes in base flow nitrate and DON concentrations, ammonium concentrations were typically at or below the detection limit, similar to the rest of the year. Our findings reveal couplings among catchment flow paths, nutrient sources, and transformations that control seasonal extremes of stream nitrogen in forested landscapes.
Komor, Stephen C.; Magner, Joseph A.
1996-01-01
This study evaluates processes that affect nitrate concentrations in groundwater beneath riparian zones in an agricultural watershed. Nitrate pathways in the upper 2 m of groundwater were investigated beneath wooded and grass-shrub riparian zones next to cultivated fields. Because trees can be important components of the overall nitrate pathway in wooded riparian zones, water sources used by riparian trees and possible effects of trees on nitrate concentrations in groundwater were also investigated. Average nitrate concentrations in shallow groundwater beneath the cultivated fields were 5.5 mg/L upgradient of the wooded riparian zone and 3.5 mg/L upgradient of the grass-shrub zone. Shallow groundwater beneath the fields passed through the riparian zones and discharged into streams that had average nitrate concentrations of 8.5 mg/L (as N). Lateral variations of δD values in groundwater showed that mixing among different water sources occurred beneath the riparian zones. In the wooded riparian zone, nitrate concentrations in shallow groundwater were diluted by upwelling, nitrate-poor, deep groundwater. Upwelling deep groundwater contained ammonium with a δ15N of 5‰ that upon nitrification and mixing with nitrate in shallow groundwater caused nitrate δ15N values in shallow groundwater to decrease by as much as 19.5‰. Stream water penetrated laterally beneath the wooded riparian zone as far as 19 m from the stream's edge and beneath the grass-shrub zone as far as 27 m from the stream's edge. Nitrate concentrations in shallow groundwater immediately upgradient of where it mixed with stream water averaged 0.4 mg/L in the wooded riparian zone and 0.8 mg/L near the grass-shrub riparian zone. Nitrate concentrations increased toward the streams because of mixing with nitrate-rich stream water. Because nitrate concentrations were larger in stream water than shallow groundwater, concentrated nitrate in the streams cannot have come from shallow groundwater at these sites. Water sources of riparian trees were identified by comparing δD values of sap water, soil water, groundwater, and stream water. Soil water was the main water source for trees in the outer 4 to 6 m of one part of the wooded riparian zone and outer 10 m of another part. Groundwater was a significant water source for trees closer to the streams where the water table was less than about 2.1 to 2.7 m below the surface. No evidence was found in the nitrate concentration profiles that trees close to the streams that took up groundwater through their roots also took up nitrate from groundwater. The lack of such evidence is attributed to the nitrate concentration profiles being insufficiently sensitive indicators of nitrate removal by trees.
Tobari, Y; Koba, K; Fukushima, K; Tokuchi, N; Ohte, N; Tateno, R; Toyoda, S; Yoshioka, T; Yoshida, N
2010-05-15
Evaluation of the openness of the nitrogen (N) cycle in forest ecosystems is important in efforts to improve forest management because the N supply often limits primary production. The use of the oxygen isotope ratio (delta(18)O) of nitrate is a promising approach to determine how effectively atmospheric nitrate can be retained in a forest ecosystem. We investigated the delta(18)O of nitrate in stream water in order to estimate the contribution of atmospheric NO(3) (-) in stream-water NO(3) (-) (f(atm)) from 26 watersheds with different stand ages (1-87 years) in Japan. The stream-water nitrate concentrations were high in young forests whereas, in contrast, old forests discharged low-nitrate stream water. These results implied a low f(atm) and a closed N cycle in older forests. However, the delta(18)O values of nitrate in stream water revealed that f(atm) values were higher in older forests than in younger forests. These results indicated that even in old forests, where the discharged N loss was small, atmospheric nitrate was not retained effectively. The steep slopes of the studied watersheds (>40 degrees ) which hinder the capturing of atmospheric nitrate by plants and microbes might be responsible for the inefficient utilization of atmospheric nitrate. Moreover, the unprocessed fraction of atmospheric nitrate in the stream-water nitrate in the forest (f(unprocessed)) was high in the young forest (78%), although f(unprocessed) was stable and low for other forests (5-13%). This high f(unprocessed) of the young forest indicated that the young forest retained neither atmospheric NO(3) (-) nor soil NO(3) (-) effectively, engendering high stream-water NO(3) (-) concentrations. Copyright (c) 2010 John Wiley & Sons, Ltd.
Spruill, T.B.; Tesoriero, A.J.; Mew, H.E.; Farrell, K.M.; Harden, S.L.; Colosimo, A.B.; Kraemer, S.R.
2005-01-01
Chemical, geologic, hydrologic, and age-dating information collected between 1999 and 2002 were used to examine the transport of contaminants, primarily nitrogen, in ground water and the pathways to surface water in a coastal plain setting in North Carolina. Data were collected from more than 35 wells and 4 surface-water sampling sites located in a 0.59 square-mile basin to examine detailed hydrogeology and geochemical processes affecting nutrient fate and transport. Two additional surface-water sampling sites were located downstream from the primary study site to evaluate basin-scale effects. Chemical and flow data also were collected at an additional 10 sites in the Coastal Plain portion of the Neuse River basin located between Kinston and New Bern, North Carolina, to evaluate loads transported in the Neuse River and primary tributary basins. At the Lizzie Research Station study site in North Carolina, horizontal flow is induced by the presence of a confining unit at shallow depth. Age-dating, chemical, and piezometric data indicate that horizontal flow from the surficial aquifer is the dominant source of ground water to streamflow. Nitrogen applied on cultivated fields at the Lizzie Research Station is substantially reduced as it moves from recharge to discharge areas. Denitrification in deeper parts of the aquifer and in riparian zones is indicated by a characterization of redox conditions in the aquifer and by the presence of excess nitrogen gas. Direct ground-water discharge of nitrate to surface water during base-flow conditions is unlikely to be significant because of strongly reducing conditions that occur in the riparian zones of these streams. Nitrate loads from a drainage tile at the study site may account for much of the nitrate load in the receiving stream, indicating that a major source of nutrients from ground water to this stream is artificial drainage. During base-flow conditions when the streams are not flowing, it is hypothesized that the mineralization of organic matter on the streambed is the source of nitrate and(or) ammonium in the stream. Base flow is a small contributor to nitrogen loads, because both flows and inorganic nitrogen concentrations are low during summer months. Effects of a confined hog operation on ground-water quality also were evaluated. The use of sprayed swine wastes to fertilize crops at the Lizzie Research Station study site since 1995 resulted in increased concentrations of nitrate and other chemical constituents in ground water beneath spray fields when compared to ground water beneath fields treated with commercial fertilizer. The nitrate concentration in ground water from the spray field well increased by a factor of 3.5 after 4 years of spray applications. Nitrate concentrations ranged from 10 to 35 milligrams per liter, and one concentration as high as 56 milligrams per liter was observed in water from this well in spring 2002. This finding is in agreement with findings of other studies conducted in the Coastal Plain of North Carolina that nitrate concentrations were significantly higher in ground water from cultivated fields sprayed with swine wastes than from fields treated with commercial fertilizer. Loads and yields of nitrogen and phosphorus in 14 streams in the Neuse River basin were evaluated for calendar years 2000 and 2001. Data indicate that anthropogenic effects on nitrogen yields were greatest in the first-order stream studied (yields were greater than 2 tons per square mile [ton/mi2] and 1 ton/mi2 or less in second- and higher-order streams) in the Little Contentnea Creek subbasin. Nitrogen yields in streams in the Contentnea Creek subbasin ranged from 0.59 to 2 ton/mi2 with typical yields of approximately 1 ton/mi2. Contentnea Creek near Evansdale had the highest yield (2 ton/mi2), indicating that a major source of nitrogen is upstream from this station. Nitrogen yields were lower at Contentnea Creek at Hookerton in 2000 and 2001 compared to previous yi
Consequences of variation in stream-landscape connections for stream nitrate retention and export
NASA Astrophysics Data System (ADS)
Handler, A. M.; Helton, A. M.; Grimm, N. B.
2017-12-01
Hydrologic and material connections among streams, the surrounding terrestrial landscape, and groundwater systems fluctuate between extremes in dryland watersheds, yet the consequences of this variation for stream nutrient retention and export remain uncertain. We explored how seasonal variation in hydrologic connection among streams, landscapes, and groundwater affect nitrate and ammonium concentrations across a dryland stream network and how this variation mediates in-stream nitrate uptake and watershed export. We conducted spatial surveys of stream nitrate and ammonium concentration across the 1200 km2 Oak Creek watershed in central Arizona (USA). In addition, we conducted pulse releases of a solution containing biologically reactive sodium nitrate, with sodium chloride as a conservative hydrologic tracer, to estimate nitrate uptake rates in the mainstem (Q>1000 L/s) and two tributaries. Nitrate and ammonium concentrations generally increased from headwaters to mouth in the mainstem. Locally elevated concentrations occurred in spring-fed tributaries draining fish hatcheries and larger irrigation ditches, but did not have a substantial effect on the mainstem nitrogen load. Ambient nitrate concentration (as N) ranged from below the analytical detection limit of 0.005 mg/L to 0.43 mg/L across all uptake experiments. Uptake length—average stream distance traveled for a nutrient atom from the point of release to its uptake—at ambient concentration ranged from 250 to 704 m and increased significantly with higher discharge, both across streams and within the same stream on different experiment dates. Vertical uptake velocity and aerial uptake rate ranged from 6.6-10.6 mm min-1 and 0.03 to 1.4 mg N m-2 min-1, respectively. Preliminary analyses indicate potentially elevated nitrogen loading to the lower portion of the watershed during seasonal precipitation events, but overall, the capacity for nitrate uptake is high in the mainstem and tributaries. Ongoing work focuses on how seasonal variability in connections between the stream and sources of nitrogen affect in-stream nitrate and ammonium uptake rates and watershed export. Episodic connections between dryland streams and the surrounding landscape can have a strong effect on stream nitrogen loads, uptake, and export.
Tesoriero, A.J.; Duff, J.H.; Wolock, D.M.; Spahr, N.E.; Almendinger, J.E.
2009-01-01
Understanding nutrient pathways to streams will improve nutrient management strategies and estimates of the time lag between when changes in land use practices occur and when water quality effects that result from these changes are observed. Nitrate and orthophosphate (OP) concentrations in several environmental compartments were examined in watersheds having a range of base flow index (BFI) values across the continental United States to determine the dominant pathways for water and nutrient inputs to streams. Estimates of the proportion of stream nitrate that was derived from groundwater increased as BFI increased. Nitrate concentration gradients between groundwater and surface water further supported the groundwater source of nitrate in these high BFI streams. However, nitrate concentrations in stream-bed pore water in all settings were typically lower than stream or upland groundwater concentrations, suggesting that nitrate discharge to streams was not uniform through the bed. Rather, preferential pathways (e.g., springs, seeps) may allow high nitrate groundwater to bypass sites of high biogeochemical transformation. Rapid pathway compartments (e.g., overland flow, tile drains) had OP concentrations that were typically higher than in streams and were important OP conveyers in most of these watersheds. In contrast to nitrate, the proportion of stream OP that is derived from ground water did not systematically increase as BFI increased. While typically not the dominant source of OP, groundwater discharge was an important pathway of OP transport to streams when BFI values were very high and when geochemical conditions favored OP mobility in groundwater. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.
Legacy Nitrate Impacts on Groundwater and Streams
NASA Astrophysics Data System (ADS)
Tesoriero, A. J.; Juckem, P. F.; Miller, M. P.
2017-12-01
Decades of recharge of high-nitrate groundwater have created a legacy—a mass of high-nitrate groundwater—that has implications for future nitrate concentrations in groundwater and in streams. In the United States, inorganic nitrogen fertilizer applications to the land surface have increased ten-fold since 1950, resulting in sharp increases in nitrate concentrations in recharging groundwater, which pose a risk to deeper groundwater and streams. This study assesses the factors that control time lags and eventual concentrations of legacy nitrate in groundwater and streams. Results from the USGS National Water-Quality Assessment Project are presented which elucidate nitrate trends in recharging groundwater, delineate redox zones and assess groundwater and stream vulnerability to legacy nitrate sources on a regional scale. This study evaluated trends and transformations of agricultural chemicals based on groundwater age and water chemistry data along flow paths from recharge areas to streams at 20 study sites across the United States. Median nitrate recharge concentrations in these agricultural areas have increased markedly over the last 50 years, from 4 to 7.5 mg N/L. The effect that nitrate accumulation in shallow aquifers will have on drinking water quality and stream ecosystems is dependent on the redox zones encountered along flow paths and on the age distribution of nitrate discharging to supply wells and streams. Delineating redox zones on a regional scale is complicated by the spatial variability of reaction rates. To overcome this limitation, we applied logistic regression and machine learning techniques to predict the probability of a specific redox condition in groundwater in the Chesapeake Bay watershed and the Fox-Wolf-Peshtigo study area in Wisconsin. By relating redox-active constituent concentrations in groundwater samples to indicators of residence time and/or electron donor availability, we were able to delineate redox zones on a regional scale - an important indicator of groundwater vulnerability and the vulnerability of streams to legacy nitrate sources.
Quantifying in-stream nitrate reaction rates using continuously-collected water quality data
Matthew Miller; Anthony Tesoriero; Paul Capel
2016-01-01
High frequency in situ nitrate data from three streams of varying hydrologic condition, land use, and watershed size were used to quantify the mass loading of nitrate to streams from two sources â groundwater discharge and event flow â at a daily time step for one year. These estimated loadings were used to quantify temporally-variable in-stream nitrate processing ...
Stream denitrification across biomes and its response to anthropogenic nitrate loading
Mulholland, P.J.; Helton, A.M.; Poole, G.C.; Hall, R.O.; Hamilton, S.K.; Peterson, B.J.; Tank, J.L.; Ashkenas, L.R.; Cooper, L.W.; Dahm, Clifford N.; Dodds, W.K.; Findlay, S.E.G.; Gregory, S.V.; Grimm, N. B.; Johnson, S.L.; McDowell, W.H.; Meyer, J.L.; Valett, H.M.; Webster, J.R.; Arango, C.P.; Beaulieu, J.J.; Bernot, M.J.; Burgin, A.J.; Crenshaw, C.L.; Johnson, L.T.; Niederlehner, B.R.; O'Brien, J. M.; Potter, J.D.; Sheibley, R.W.; Sobota, D.J.; Thomas, S.M.
2008-01-01
Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing and terrestrial ecosystems are becoming increasingly nitrogen-saturated, causing more bioavailable nitrogen to enter groundwater and surface waters. Large-scale nitrogen budgets show that an average of about 20-25 per cent of the nitrogen added to the biosphere is exported from rivers to the ocean or inland basins, indicating that substantial sinks for nitrogen must exist in the landscape. Streams and rivers may themselves be important sinks for bioavailable nitrogen owing to their hydrological connections with terrestrial systems, high rates of biological activity, and streambed sediment environments that favour microbial denitrification. Here we present data from nitrogen stable isotope tracer experiments across 72 streams and 8 regions representing several biomes. We show that total biotic uptake and denitrification of nitrate increase with stream nitrate concentration, but that the efficiency of biotic uptake and denitrification declines as concentration increases, reducing the proportion of in-stream nitrate that is removed from transport. Our data suggest that the total uptake of nitrate is related to ecosystem photosynthesis and that denitrification is related to ecosystem respiration. In addition, we use a stream network model to demonstrate that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks. ??2008 Nature Publishing Group.
COMPARTMENTAL MODEL OF NITRATE RETENTION IN STREAMS
A compartmental modeling approach is presented to route nitrate retention along a cascade of stream reach sections. A process transfer function is used for transient storage equations with first order reaction terms to represent nitrate uptake in the free stream, and denitrifica...
NASA Astrophysics Data System (ADS)
Sebestyen, S. D.; Shanley, J. B.; Pellerin, B.; Saraceno, J.; Aiken, G. R.; Boyer, E. W.; Doctor, D. H.; Kendall, C.
2009-05-01
There is a need to understand the coupled biogeochemical and hydrological processes that control stream hydrochemistry in upland forested catchments. At watershed 9 (W-9) of the Sleepers River Research Watershed in the northeastern USA, we use high-frequency sampling, environmental tracers, end-member mixing analysis, and stream reach mass balances to understand dynamic factors affect forms and concentrations of nitrogen and organic matter in streamflow. We found that rates of stream nitrate processing changed during autumn baseflow and that up to 70% of nitrate inputs to a stream reach were retained. At the same time, the stream reach was a net source of the dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) fractions of dissolved organic matter (DOM). The in-stream nitrate loss and DOM gains are examples of hot moments of biogeochemical transformations during autumn when deciduous litter fall increases DOM availability. As hydrological flowpaths changed during rainfall events, the sources and transformations of nitrate and DOM differed from baseflow. For example, during storm flow we measured direct inputs of unprocessed atmospheric nitrate to streams that were as large as 30% of the stream nitrate loading. At the same time, stream DOM composition shifted to reflect inputs of reactive organic matter from surficial upland soils. The transport of atmospheric nitrate and reactive DOM to streams underscores the importance of quantifying source variation during short-duration stormflow events. Building upon these findings we present a conceptual model of interacting ecosystem processes that control the flow of water and nutrients to streams in a temperate upland catchment.
Persistent Influences of the 2002 Hayman Fire on Stream Nitrate and Dissolved Organic Carbon
NASA Astrophysics Data System (ADS)
Rhoades, C.; Pierson, D. N.; Fegel, T. S., II; Chow, A. T.; Covino, T. P.
2016-12-01
Large, high severity wildfires alter the physical and biological conditions that determine how watersheds retain and release nutrients and regulate stream water quality. For five years after the 2002 Hayman Fire burned in Colorado conifer forests, stream nitrate concentrations and export increased steadily in watersheds with extensive high-severity burning. Stream temperature and turbidity also increased in relation to the extent of high-severity burning and remained elevated above background levels throughout the initial five year post-fire period. Our recent sampling documents that 14 years after the Hayman Fire stream nitrate remains an order of magnitude higher in extensively-burned (35-90%) compared to unburned watersheds (0.2 vs 2.8 mg L-1). Nitrate represents 83% of the total dissolved N in extensively-burned watersheds compared to 29% in unburned watersheds. In contrast, dissolved organic carbon (DOC), was highest in watersheds that burned to a moderate extent (10-20%) and lowest in those with extensive burning. Catchments with a moderate extent burned had DOC concentrations 2.5 and 1.7 times more than those with extensive burning and unburned catchments, respectively. Peak concentrations of DOC and nitrate track the rising limb of the streamflow hydrograph and reach a maximum in May, but patterns among burn extent categories were seasonally consistent. Current riparian conditions are linked to stream nitrate in burned watersheds. For example, stream nitrate increases proportionally to the extent of riparian zones with low shrub cover (R2 = 0.76). We found signs of watershed recovery compared to the initial post-fire period; stream temperature and turbidity remained elevated in extensively burned catchments, but increases were only significant during the spring season. The persistent stream nitrate concentrations as well as the relation between riparian cover and post-fire stream nitrate may help prioritize restoration planting efforts and mitigate chronic, elevated nitrate export from burned watersheds.
NASA Astrophysics Data System (ADS)
Miller, M. P.; Tesoriero, A. J.; Hood, K.; Terziotti, S.; Wolock, D.
2017-12-01
The myriad hydrologic and biogeochemical processes taking place in watersheds occurring across space and time are integrated and reflected in the quantity and quality of water in streams and rivers. Collection of high-frequency water quality data with sensors in surface waters provides new opportunities to disentangle these processes and quantify sources and transport of water and solutes in the coupled groundwater-surface water system. A new approach for separating the streamflow hydrograph into three components was developed and coupled with high-frequency specific conductance and nitrate data to estimate time-variable watershed-scale nitrate loading from three end-member pathways - dilute quickflow, concentrated quickflow, and slowflow groundwater - to two streams in central Wisconsin. Time-variable nitrate loads from the three pathways were estimated for periods of up to two years in a groundwater-dominated and a quickflow-dominated stream, using only streamflow and in-stream water quality data. The dilute and concentrated quickflow end-members were distinguished using high-frequency specific conductance data. Results indicate that dilute quickflow contributed less than 5% of the nitrate load at both sites, whereas 89±5% of the nitrate load at the groundwater-dominated stream was from slowflow groundwater, and 84±13% of the nitrate load at the quickflow-dominated stream was from concentrated quickflow. Concentrated quickflow nitrate concentrations varied seasonally at both sites, with peak concentrations in the winter that were 2-3 times greater than minimum concentrations during the growing season. Application of this approach provides an opportunity to assess stream vulnerability to non-point source nitrate loading and expected stream responses to current or changing conditions and practices in watersheds.
Modeling Land Application of Food-Processing Wastewater in the Central Valley, California
NASA Astrophysics Data System (ADS)
Rubin, Y.; Benito, P.; Miller, G.; McLaughlin, J.; Hou, Z.; Hermanowicz, S.; Mayer, U.
2007-12-01
California's Central Valley contains over 640 food-processing plants, serving a multi-billion dollar agricultural industry. These processors consume approximately 7.9 x 107 m3 of water per year. Approximately 80% of these processors discharge the resulting wastewater, which is typically high in organic matter, nitrogen, and salts, to land, and many of these use land application as a treatment method. Initial investigations revealed elevated salinity levels to be the most common form of groundwater degradation near land application sites, followed by concentrations of nitrogen compounds, namely ammonia and nitrate. Enforcement actions have been taken against multiple food processors, and the regulatory boards have begun to re-examine the land disposal permitting process. This paper summarizes a study that was commissioned in support of these actions. The study has multiple components which will be reviewed briefly, including: (1) characterization of the food-processing related waste stream; (2) fate and transport of the effluent waste stream in the unsaturated zone at the land application sites; (3) fate and transport of the effluent waste stream at the regional scale; (4) predictive uncertainty due to spatial variability and data scarcity at the land application sites and at the regional scale; (5) problem mitigation through off-site and in-situ actions; (6) long-term solutions. The emphasis of the talk will be placed on presenting and demonstrating a stochastic framework for modeling the transport and attenuation of these wastes in the vadose zone and in the saturated zone, and the related site characterization needs, as affected by site conditions, water table depth, waste water application rate, and waste constituent concentrations.
Vulnerability of streams to legacy nitrate sources
Tesoriero, Anthony J.; Duff, John H.; Saad, David A.; Spahr, Norman E.; Wolock, David M.
2013-01-01
The influence of hydrogeologic setting on the susceptibility of streams to legacy nitrate was examined at seven study sites having a wide range of base flow index (BFI) values. BFI is the ratio of base flow to total streamflow volume. The portion of annual stream nitrate loads from base flow was strongly correlated with BFI. Furthermore, dissolved oxygen concentrations in streambed pore water were significantly higher in high BFI watersheds than in low BFI watersheds suggesting that geochemical conditions favor nitrate transport through the bed when BFI is high. Results from a groundwater-surface water interaction study at a high BFI watershed indicate that decades old nitrate-laden water is discharging to this stream. These findings indicate that high nitrate levels in this stream may be sustained for decades to come regardless of current practices. It is hypothesized that a first approximation of stream vulnerability to legacy nutrients may be made by geospatial analysis of watersheds with high nitrogen inputs and a strong connection to groundwater (e.g., high BFI).
Karl W. J. Williard; David R. DeWalle; Pamela J. Edwards
2003-01-01
Twenty-seven forested watersheds in northern West Virginia were sampled for stream nitrate concentrations during summer 1997 and fall 1998 baseflow periods to determine if Fernow watershed 4, an often-cited and studied nitrogen saturated basin, was anomalous or regionally representative in terms of stream nitrate levels. Baseflow stream NO3-N...
Kauffman, Leon J.; Baehr, Arthur L.; Ayers, Mark A.; Stackelberg, Paul E.
2001-01-01
Residents of the southern New Jersey Coastal Plain are increasingly reliant on the unconfined Kirkwood-Cohansey aquifer system for public water supply as a result of increasing population and restrictions on withdrawals from the deeper, confined aquifers. Elevated nitrate concentrations above background levels have been found in wells in the surficial aquifer system in agricultural and urban parts of this area. A three-dimensional steady-state ground-water-flow model of a 400-square-mile study area near Glassboro, New Jersey, was used in conjunction with particle tracking to examine the effects of land use and travel time on the distribution of nitrate in ground and surface water in southern New Jersey. Contributing areas and ground-water ages, or travel times, of water at ground-water discharge points (streams and wells) in the study area were simulated. Concentrations of nitrate were computed by linking land use and age-dependent nitrate concentrations in recharge to the discharge points. Median concentrations of nitrate in water samples collected during 1996 from shallow monitoring wells in different land-use areas were used to represent the concentration of nitrate in aquifer recharge since 1990. On the basis of upward trends in the use of nitrogen fertilizer, the concentrations of nitrate in aquifer recharge in agricultural and urban areas were assumed to have increased linearly from the background value in 1940 (0.07 mg/L as N) to the 1990 (2.5-14 mg/L as N) concentrations. Model performance was evaluated by comparing the simulation results to measured nitrate concentrations and apparent ground-water ages. Apparent ground-water ages at 32 monitoring wells in the study area determined from tritium/helium-3 ratios and sulfur hexafluoride concentrations favorably matched simulated travel times to these wells. Simulated nitrate concentrations were comparable to concentrations measured in 27 water-supply wells in the study area. A time series (1987-98) of nitrate concentrations at base-flow conditions in three streams that drain basins of various sizes and with various land uses was compared to simulated concentrations in these streams. In all three of the streams, a reasonable fit to the measured concentrations was achieved by multiplying the simulated concentration by 0.6. Because nitrate appeared to move conservatively (not degraded or adsorbed) in ground water to wells, the apparent non-conservative behavior in streams indicates that about 40 percent of the nitrate in aquifer recharge is removed by denitrification in the aquifer near the streams and (or) by in-stream processes. The model was used to evaluate the effects of various nitrate management options on the concentration of nitrate in streams and water-supply wells. Nitrate concentrations were simulated under the following management alternatives: an immediate ban on nitrate input, reduction of input at a constant rate, and fixed input at the current (2000) level. The time required for water to move through the aquifer results in a time lag between the reduction of nitrate input in recharge and the reduction of nitrate concentration in streams and wells. In the gradual-reduction alternative, nitrate concentrations in streams and wells continued to increase for several years after the reduction was enacted. In both the immediate-ban and gradual-reduction alternatives, nitrate concentrations remained elevated above background concentrations long after nitrate input ceased. In the fixed-use alternative, concentrations in streams and wells continued to increase for 30 to 40 years before reaching a constant level. The spatial distributions of simulated nitrate concentrations in streams in 2000 and 2050 were examined with the assumption of no change in land use, nitrate concentration in recharge, or ground-water withdrawals. As expected, nitrate concentrations were highest in agricultural areas and lowest in largely undeveloped areas. Changes in concentration
Watanabe, Mirai; Miura, Shingo; Hasegawa, Shun; Koshikawa, Masami K; Takamatsu, Takejiro; Kohzu, Ayato; Imai, Akio; Hayashi, Seiji
2018-04-28
High concentrations of nitrate have been detected in streams flowing from nitrogen-saturated forests; however, the spatial variations of nitrate leaching within those forests and its causes remain poorly explored. The aim of this study is to evaluate the influences of catchment topography and coniferous coverage on stream nitrate concentrations in a nitrogen-saturated forest. We measured nitrate concentrations in the baseflow of headwater streams at 40 montane forest catchments on Mount Tsukuba in central Japan, at three-month intervals for 1 year, and investigated their relationship with catchment topography and with coniferous coverage. Although stream nitrate concentrations varied from 0.5 to 3.0 mgN L -1 , those in 31 catchments consistently exceeded 1 mgN L -1 , indicating that this forest had experienced nitrogen saturation. A classification and regression tree analysis with multiple environmental factors showed that the mean slope gradient and coniferous coverage were the best and second best, respectively, at explaining inter-catchment variance of stream nitrate concentrations. This analysis suggested that the catchments with steep topography and high coniferous coverage tend to have high nitrate concentrations. Moreover, in the three-year observation period for five adjacent catchments, the two catchments with relatively higher coniferous coverage consistently had higher stream nitrate concentrations. Thus, the spatial variations in stream nitrate concentrations were primarily regulated by catchment steepness and, to a lesser extent, coniferous coverage in this nitrogen-saturated forest. Our results suggest that a decrease in coniferous coverage could potentially contribute to a reduction in nitrate leaching from this nitrogen-saturated forest, and consequently reduce the risk of nitrogen overload for the downstream ecosystems. This information will allow land managers and researchers to develop improved management plans for this and similar forests in Japan and elsewhere. Copyright © 2018 Elsevier B.V. All rights reserved.
Elevated nitrate levels in streams and ground water pose human and ecological threats. Microbial denitrification removes nitrate from ground water but requires anaerobic (saturated) conditions and adequate supply of dissolved organic carbon from detritus and organic soils. Con...
Diminished Stream Nitrate Concentrations Linked to Dissolved Organic Carbon Dynamics After Leaf Fall
NASA Astrophysics Data System (ADS)
Sebestyen, S. D.; Shanley, J. B.; Boyer, E. W.; Doctor, D. H.; Kendall, C.
2004-05-01
Thermodynamic coupling of the nitrogen and carbon cycles has broad implications for controls on catchment nutrient fluxes. In the northeast US, leaf fall occurs in early October and the availability of organic carbon increases as the leaves decompose. At the Sleepers River Research Watershed in northeastern Vermont (USA), we sampled stream chemistry from seven nested catchments to determine how stream dissolved organic carbon (DOC) and nitrate vary as a function of flow conditions, land-use, and basin size in response to leaf fall. Following leaf fall, nitrate concentration patterns were quantitatively different from other times of the year. Under baseflow conditions, stream and soil water DOC concentrations were higher than normal, whereas nitrate concentrations declined sharply at the five smallest catchments and more modestly at the two largest catchments. Under high flow conditions, flushing of nitrate was observed, as is typical for stormflow response at Sleepers River. Our field data suggest that in-stream processing of nitrate is likely thermodynamically and kinetically favorable under baseflow but not at higher flow conditions when expanding variable source areas make hydrological connections between nitrate source areas and streams. We are working to evaluate this hypothesis with isotopic and other monitoring data, and to model the coupled interactions of water, DOC, and nitrate fluxes in these nested catchments.
Tesoriero, Anthony J.; Spruill, Timothy B.; Mew, H.E.; Farrell, Kathleen M.; Harden, Stephen L.
2005-01-01
Nitrogen transport and groundwater-surface water interactions were examined in a coastal plain watershed in the southeastern United States. Groundwater age dates, calculated using chlorofluorocarbon and tritium concentrations, along with concentrations of nitrogen species and other redox-active constituents, were used to evaluate the fate and transport of nitrate. Nitrate is stable only in recently recharged (<10 years) water found in the upper few meters of saturated thickness in the upland portion of a surficial aquifer. Groundwater with a residence time between 10 and 30 years typically has low nitrate and elevated excess N2 concentrations, indications that denitrification has reduced nitrate concentrations. Groundwater older than 30 years also has low nitrate concentrations but contains little or no excess N2, suggesting that this water did not contain elevated concentrations of nitrate along its flow path. Nitrate transport to streams varies between first- and third-order streams. Hydrologic, lithologic, and chemical data suggest that the surficial aquifer is the dominant source of flow and nitrate to a first-order stream. Iron-reducing conditions occur in groundwater samples from the bed and banks of the first-order stream, suggesting that direct groundwater discharge is denitrified prior to entering the stream. However, nitrogen from the surficial aquifer is transported directly to the stream via a tile drain that bypasses these reduced zones. In the alluvial valley of a third-order stream the erosion of a confining layer creates a much thicker unconfined alluvial aquifer with larger zones of nitrate stability. Age dating and chemical information (SiO 2, Na/K ratios) suggest that water in the alluvial aquifer is derived from short flow paths through the riparian zone and/or from adjacent streams during high-discharge periods. Copyright 2005 by the American Geophysical Union.
NASA Astrophysics Data System (ADS)
Briand, Cyrielle; Sebilo, Mathieu; Louvat, Pascale; Chesnot, Thierry; Vaury, Véronique; Schneider, Maude; Plagnes, Valérie
2017-02-01
Nitrate content of surface waters results from complex mixing of multiple sources, whose signatures can be modified through N reactions occurring within the different compartments of the whole catchment. Despite this complexity, the determination of nitrate origin is the first and crucial step for water resource preservation. Here, for the first time, we combined at the catchment scale stable isotopic tracers (δ15N and δ18O of nitrate and δ11B) and fecal indicators to trace nitrate sources and pathways to the stream. We tested this approach on two rivers in an agricultural region of SW France. Boron isotopic ratios evidenced inflow from anthropogenic waters, microbiological markers revealed organic contaminations from both human and animal wastes. Nitrate δ15N and δ18O traced inputs from the surface leaching during high flow events and from the subsurface drainage in base flow regime. They also showed that denitrification occurred within the soils before reaching the rivers. Furthermore, this study highlighted the determinant role of the soil compartment in nitrate formation and recycling with important spatial heterogeneity and temporal variability.
Hill, Dagne D; Owens, William E; Tchounwou, Paul B
2005-04-01
The objective of this research was to compare the chemical/physical parameters and bacterial qualities of selected surface water streams in Louisiana, including a natural stream (control) and an animal waste related stream. Samples were collected and analyzed for fecal coliforms. Fecal coliforms isolated from these samples were identified to the species level. Chemical analysis was performed following standard test protocols (LaMotte 2002). An analysis of biological oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon (TOC), total dissolved solids (TDS), conductivity, pH, temperature, ammonia nitrogen, nitrate nitrogen, iron, copper, phosphate, potassium, sulfate, turbidity, zinc and bacterial levels was performed following standard test protocols as presented in Standard Methods for the Examination of Water and Wastewater [9]. Results of the comparisons of the various surface water streams showed that phosphate levels, according to Mitchell and Stapp, were considered good for Lake Claiborne (control) and Bayou Dorcheat. The levels were found to be .001 mg/L and .007 mg/L respectively. Other streams associated with animal waste, had higher phosphate levels of 2.07 mg/L and 2.78 mg/L, respectively. Conductivity and total dissolved solids (TDS) levels were the lowest in Lake Claiborne and highest in the Hill Farm Research Station stream. It can be concluded from the data that some bacterial levels and various nutrient levels can be affected in water resources due to non-point source pollution. Many of these levels will remain unaffected.
Radioactive Demonstrations Of Fluidized Bed Steam Reforming (FBSR) With Hanford Low Activity Wastes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jantzen, C. M.; Crawford, C. L.; Burket, P. R.
Several supplemental technologies for treating and immobilizing Hanford low activity waste (LAW) are being evaluated. One immobilization technology being considered is Fluidized Bed Steam Reforming (FBSR) which offers a low temperature (700-750?C) continuous method by which wastes high in organics, nitrates, sulfates/sulfides, or other aqueous components may be processed into a crystalline ceramic (mineral) waste form. The granular waste form produced by co-processing the waste with kaolin clay has been shown to be as durable as LAW glass. The FBSR granular product will be monolithed into a final waste form. The granular component is composed of insoluble sodium aluminosilicate (NAS)more » feldspathoid minerals such as sodalite. Production of the FBSR mineral product has been demonstrated both at the industrial, engineering, pilot, and laboratory scales on simulants. Radioactive testing at SRNL commenced in late 2010 to demonstrate the technology on radioactive LAW streams which is the focus of this study.« less
Kaushal, S.S.; Groffman, P.M.; Band, L.E.; Shields, C.A.; Morgan, R.P.; Palmer, Margaret A.; Belt, K.T.; Swan, C.M.; Findlay, S.E.G.; Fisher, G.T.
2008-01-01
We investigated regional effects of urbanization and land use change on nitrate concentrations in approximately 1,000 small streams in Maryland during record drought and wet years in 2001-2003. We also investigated changes in nitrate-N export during the same time period in 8 intensively monitored small watersheds across an urbanization gradient in Baltimore, Maryland. Nitrate-N concentrations in Maryland were greatest in agricultural streams, urban streams, and forest streams respectively. During the period of record drought and wet years, nitrate-N exports in Baltimore showed substantial variation in 6 suburban/urban streams (2.9-15.3 kg/ha/y), 1 agricultural stream (3.4-38.9 kg/ha/y), and 1 forest stream (0.03-0.2 kg/ ha/y). Interannual variability was similar for small Baltimore streams and nearby well-monitored tributaries and coincided with record hypoxia in Chesapeake Bay. Discharge-weighted mean annual nitrate concentrations showed a variable tendency to decrease/increase with changes in annual runoff, although total N export generally increased with annual runoff. N retention in small Baltimore watersheds during the 2002 drought was 85%, 99%, and 94% for suburban, forest, and agricultural watersheds, respectively, and declined to 35%, 91%, and 41% during the wet year of 2003. Our results suggest that urban land use change can increase the vulnerability of ecosystem nitrogen retention functions to climatic variability. Further work is necessary to characterize patterns of nitrate-N export and retention in small urbanizing watersheds under varying climatic conditions to improve future forecasting and watershed scale restoration efforts aimed at improving nitrate-N retention. ?? 2008 American Chemical Society.
Alternative solutions for the bio-denitrification of landfill leachates using pine bark and compost.
Trois, Cristina; Pisano, Giulia; Oxarango, Laurent
2010-06-15
Nitrified leachate may still require an additional bio-denitrification step, which occurs with the addition of often-expensive chemicals as carbon source. This study explores the applicability of low-cost carbon sources such as garden refuse compost and pine bark for the denitrification of high strength landfill leachates. The overall objective is to assess efficiency, kinetics and performance of the substrates in the removal of high nitrate concentrations. Garden refuse and pine bark are currently disposed of in general waste landfills in South Africa, separated from the main waste stream. A secondary objective is to assess the feasibility of re-using green waste as by-product of an integrated waste management system. Denitrification processes in fixed bed reactors were simulated at laboratory scale using anaerobic batch tests and leaching columns packed with immature compost and pine bark. Biologically treated leachate from a Sequencing Batch Reactor (SBR) with nitrate concentrations of 350, 700 and 1100 mgN/l were used for the trials. Preliminary results suggest that, passed the acclimatization step (40 days for both substrates), full denitrification is achieved in 10-20 days for the pine bark and 30-40 days for the compost. Copyright 2010 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Sebestyen, Stephen D.; Boyer, Elizabeth W.; Shanley, James B.
2009-06-01
In coming decades, higher annual temperatures, increased growing season length, and increased dormant season precipitation are expected across the northeastern United States in response to anthropogenic forcing of global climate. We synthesized long-term stream hydrochemical data from the Sleepers River Research Watershed in Vermont, United States, to explore the relationship of catchment wetness to stream nitrate and DOC loadings. We modeled changes in growing season length and precipitation patterns to simulate future climate scenarios and to assess how stream nutrient loadings respond to climate change. Model results for the 2070-2099 time period suggest that stream nutrient loadings during both the dormant and growing seasons will respond to climate change. During a warmer climate, growing season stream fluxes (runoff +20%, nitrate +57%, and DOC +58%) increase as more precipitation (+28%) and quick flow (+39%) occur during a longer growing season (+43 days). During the dormant season, stream water and nutrient loadings decrease. Net annual stream runoff (+8%) and DOC loading (+9%) increases are commensurate with the magnitude of the average increase of net annual precipitation (+7%). Net annual stream water and DOC loadings are primarily affected by increased dormant season precipitation. In contrast, decreased annual loading of stream nitrate (-2%) reflects a larger effect of growing season controls on stream nitrate and the effects of lengthened growing seasons in a warmer climate. Our findings suggest that leaching of nitrate and DOC from catchment soils will be affected by anthropogenic climate forcing, thereby affecting the timing and magnitude of annual stream loadings in the northeastern United States.
URBAN STREAM BURIAL INCREASES WATERSHED-SCALE NITRATE EXPORT
Nitrogen (N) uptake in streams is an important ecosystem service that may be affected by the widespread burial of streams in stormwater pipes in urban watersheds. We predicted that stream burial reduces the capacity of streams to remove nitrate (NO3-) from the water column by in...
Thakur, P; Ballard, S; Hardy, R
2014-11-04
Recent incidents at the nation's only operating deep geologic nuclear waste repository, the Waste Isolation Pilot Plant (WIPP), resulted in the release of americium and plutonium from one or more defense-related transuranic (TRU) waste containers into the environment. WIPP is a U.S. Department of Energy mined geologic repository that has been in operation since March, 1999. Over 85,000 m3 of waste in various vented payload containers have been emplaced in the repository. The primary radionuclides within the disposed waste are 239+240Pu and 241Am, which account for more than 99% of the total TRU radioactivity disposed and scheduled for disposal in the repository. For the first time in its 15 years of operation, there was an airborne radiation release from the WIPP at approximately 11:30 PM Mountain Standard Time (MST) on Friday, February 14, 2014. The radiation release was likely caused by a chemical reaction inside a TRU waste drum that contained nitrate salts and organic sorbent materials. In a recent news release, DOE announced that photos taken of the waste underground showed evidence of heat and gas pressure resulting in a deformed lid, in material expelled through that deformation, and in melted plastic and rubber and polyethylene in the vicinity of that drum. Recent entries into underground Panel 7 have confirmed that at least one waste drum containing a nitrate salt bearing waste stream from Los Alamos National Laboratory was breached underground and was the most likely source of the release. Further investigation is underway to determine if other containers contributed to the release. Air monitoring across the WIPP site intensified following the first reports of radiation detection underground to ascertain whether or not there were releases to the ground surface. Independent analytical results of air filters from sampling stations on and near the WIPP facility have been released by us at the Carlsbad Environmental Monitoring & Research Center and confirmed trace amounts of 241Am and 239+240Pu, at ratios reflecting the suspect waste stream. The highest activity detected offsite was 115.2 μBq/m3 for 241Am and 10.2 μBq/m3 for 239+240 Pu. These concentrations in air were very small, localized, and below any level of public health or environmental concern.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.
2011-06-08
Prior laboratory testing identified sodium nitrate and nitrite to be the most promising agents to minimize hydrogen generation from uranium metal aqueous corrosion in Hanford Site K Basin sludge. Of the two, nitrate was determined to be better because of higher chemical capacity, lower toxicity, more reliable efficacy, and fewer side reactions than nitrite. The present lab tests were run to determine if nitrate’s beneficial effects to lower H2 generation in simulated and genuine sludge continued for simulated sludge mixed with agents to immobilize water to help meet the Waste Isolation Pilot Plant (WIPP) waste acceptance drainable liquid criterion. Testsmore » were run at ~60°C, 80°C, and 95°C using near spherical high-purity uranium metal beads and simulated sludge to emulate uranium-rich KW containerized sludge currently residing in engineered containers KW-210 and KW-220. Immobilization agents tested were Portland cement (PC), a commercial blend of PC with sepiolite clay (Aquaset II H), granulated sepiolite clay (Aquaset II G), and sepiolite clay powder (Aquaset II). In all cases except tests with Aquaset II G, the simulated sludge was mixed intimately with the immobilization agent before testing commenced. For the granulated Aquaset II G clay was added to the top of the settled sludge/solution mixture according to manufacturer application directions. The gas volumes and compositions, uranium metal corrosion mass losses, and nitrite, ammonia, and hydroxide concentrations in the interstitial solutions were measured. Uranium metal corrosion rates were compared with rates forecast from the known uranium metal anoxic water corrosion rate law. The ratios of the forecast to the observed rates were calculated to find the corrosion rate attenuation factors. Hydrogen quantities also were measured and compared with quantities expected based on non-attenuated H2 generation at the full forecast anoxic corrosion rate to arrive at H2 attenuation factors. The uranium metal corrosion rates in water alone and in simulated sludge were near or slightly below the metal-in-water rate while nitrate-free sludge/Aquaset II decreased rates by about a factor of 3. Addition of 1 M nitrate to simulated sludge decreased the corrosion rate by a factor of ~5 while 1 M nitrate in sludge/Aquaset II mixtures decreased the corrosion rate by ~2.5 compared with the nitrate-free analogues. Mixtures of simulated sludge with Aquaset II treated with 1 M nitrate had uranium corrosion rates about a factor of 8 to 10 lower than the water-only rate law. Nitrate was found to provide substantial hydrogen mitigation for immobilized simulant sludge waste forms containing Aquaset II or Aquaset II G clay. Hydrogen attenuation factors of 1000 or greater were determined at 60°C for sludge-clay mixtures at 1 M nitrate. Hydrogen mitigation for tests with PC and Aquaset II H (which contains PC) were inconclusive because of suspected failure to overcome induction times and fully enter into anoxic corrosion. Lessening of hydrogen attenuation at ~80°C and ~95°C for simulated sludge and Aquaset II was observed with attenuation factors around 100 to 200 at 1 M nitrate. Valuable additional information has been obtained on the ability of nitrate to attenuate hydrogen gas generation from solution, simulant K Basin sludge, and simulant sludge with immobilization agents. Details on characteristics of the associated reactions were also obtained. The present testing confirms prior work which indicates that nitrate is an effective agent to attenuate hydrogen from uranium metal corrosion in water and simulated K Basin sludge to show that it is also effective in potential candidate solidified K Basin waste forms for WIPP disposal. The hydrogen mitigation afforded by nitrate appears to be sufficient to meet the hydrogen generation limits for shipping various sludge waste streams based on uranium metal concentrations and assumed waste form loadings.« less
NASA Astrophysics Data System (ADS)
Woodward, Simon James Roy; Wöhling, Thomas; Rode, Michael; Stenger, Roland
2017-09-01
The common practice of infrequent (e.g., monthly) stream water quality sampling for state of the environment monitoring may, when combined with high resolution stream flow data, provide sufficient information to accurately characterise the dominant nutrient transfer pathways and predict annual catchment yields. In the proposed approach, we use the spatially lumped catchment model StreamGEM to predict daily stream flow and nitrate concentration (mg L-1 NO3-N) in four contrasting mesoscale headwater catchments based on four years of daily rainfall, potential evapotranspiration, and stream flow measurements, and monthly or daily nitrate concentrations. Posterior model parameter distributions were estimated using the Markov Chain Monte Carlo sampling code DREAMZS and a log-likelihood function assuming heteroscedastic, t-distributed residuals. Despite high uncertainty in some model parameters, the flow and nitrate calibration data was well reproduced across all catchments (Nash-Sutcliffe efficiency against Log transformed data, NSL, in the range 0.62-0.83 for daily flow and 0.17-0.88 for nitrate concentration). The slight increase in the size of the residuals for a separate validation period was considered acceptable (NSL in the range 0.60-0.89 for daily flow and 0.10-0.74 for nitrate concentration, excluding one data set with limited validation data). Proportions of flow and nitrate discharge attributed to near-surface, fast seasonal groundwater and slow deeper groundwater were consistent with expectations based on catchment geology. The results for the Weida Stream in Thuringia, Germany, using monthly as opposed to daily nitrate data were, for all intents and purposes, identical, suggesting that four years of monthly nitrate sampling provides sufficient information for calibration of the StreamGEM model and prediction of catchment dynamics. This study highlights the remarkable effectiveness of process based, spatially lumped modelling with commonly available monthly stream sample data, to elucidate high resolution catchment function, when appropriate calibration methods are used that correctly handle the inherent uncertainties.
Seasonal and event-scale controls on dissolved organic carbon and nitrate flushing from catchments
NASA Astrophysics Data System (ADS)
Sebestyen, S. D.; Boyer, E. W.; Shanley, J. B.; Doctor, D. H.
2005-05-01
To explore terrestrial and aquatic linkages controlling nutrient dynamics in forested catchments, we collected high-frequency samples from 2002 to 2004 at the Sleepers River Research Watershed in northeastern Vermont USA. We measured DOC (dissolved organic carbon), SUVA (specific UV absorbance), nitrate, and major ion concentrations over a wide range of flow conditions. In addition, weekly samples since 1991 provide a longer term record of stream nutrient fluxes. During events, DOC concentrations increased with flow consistent with the flushing of a large reservoir of mobile organic carbon from forest soils. Higher concentrations of DOC and SUVA in the growing versus dormant season illustrated seasonal variation in sources, characteristics (i.e. reactivity), availability, and controls on the flushing response of organic matter from the landscape to streams. In contrast, stream nitrate concentrations increased with flow but only when catchments "wetted-up" after baseflow periods. Growing season stream nitrate responses were dependent on short-term antecedent moisture conditions indicating rapid depletion of the soil nitrate reservoir when source areas became hydrologically connected to streams. While the different response patterns emphasized variable source and biogeochemical controls in relation to flow patterns, coupled carbon and nitrogen biogeochemical processes were also important controls on stream nutrient fluxes. In particular, leaf fall was a critical time when reactive DOC from freshly decomposing litter fueled in-stream consumption of nitrate leading to sharp declines of stream nitrate concentrations. Our measurements highlight the importance of "hot spots" and "hot moments" of biogeochemical and hydrological processes that control stream responses. Furthermore, our work illustrates how carbon, nitrogen, and water cycles are coupled in catchments, and provides a conceptual model for future work aimed at modeling forest stream hydrochemistry at the catchment scale.
Effects of Urban Stream Burial on Organic Matter Dynamics and Reach Scale Nitrate Retention
Nitrogen (N) retention in streams is an important ecosystem service that may be affected by the widespread burial of streams in stormwater pipes in urban watersheds. We predicted that stream burial suppresses the capacity of streams to retain nitrate (NO3-) by eliminating primar...
Atmospheric nitrate export in streams along a montane to urban gradient.
Bourgeois, Ilann; Savarino, Joel; Némery, Julien; Caillon, Nicolas; Albertin, Sarah; Delbart, Franck; Voisin, Didier; Clément, Jean-Christophe
2018-08-15
Nitrogen (N) emissions associated with urbanization exacerbate the atmospheric N influx to remote ecosystems - like mountains -, leading to well-documented detrimental effects on ecosystems (e.g., soil acidification, pollution of freshwaters). Here, the importance and fate of N deposition in a watershed was evaluated along a montane to urban gradient, using a multi-isotopic tracers approach (Δ 17 O, δ 15 N, δ 18 O of nitrate, δ 2 H and δ 18 O of water). In this setting, the montane streams had higher proportions of atmospheric nitrate compared to urban streams, and exported more atmospheric nitrate on a yearly basis (0.35 vs 0.10 kg-Nha -1 yr -1 ). In urban areas, nitrate exports were driven by groundwater, whereas in the catchment head nitrate exports were dominated by surface runoff. The main sources of nitrate to the montane streams were microbial nitrification and atmospheric deposition, whereas microbial nitrification and sewage leakage contributed most to urban streams. Based on the measurement of δ 15 N and δ 18 O-NO 3 - , biological processes such as denitrification or N assimilation were not predominant in any streams in this study. The observed low δ 15 N and δ 18 O range of terrestrial nitrate (i.e., nitrate not coming from atmospheric deposition) in surface water compared to literature suggests that atmospheric deposition may be underestimated as a direct source of N. Copyright © 2018 Elsevier B.V. All rights reserved.
Nutrient interleaving below the mixed layer of the Kuroshio Extension Front
NASA Astrophysics Data System (ADS)
Nagai, Takeyoshi; Clayton, Sophie
2017-08-01
Nitrate interleaving structures were observed below the mixed layer during a cruise to the Kuroshio Extension in October 2009. In this paper, we investigate the formation mechanisms for these vertical nitrate anomalies, which may be an important source of nitrate to the oligotrphoc surface waters south of the Kuroshio Extension Front. We found that nitrate concentrations below the main stream of the Kuroshio Extension were elevated compared to the ambient water of the same density ( σ 𝜃 = 23.5-25). This appears to be analogous to the "nutrient stream" below the mixed layer, associated with the Gulf Stream. Strong turbulence was observed above the vertical nitrate anomaly, and we found that this can drive a large vertical turbulent nitrate flux >O (1 mmol N m-2 day-1). A realistic, high-resolution (2 km) numerical simulation reproduces the observed Kuroshio nutrient stream and nitrate interleaving structures, with similar lateral and vertical scales. The model results suggest that the nitrate interleaving structures are first generated at the western side of the meander crest on the south side of the Kuroshio Extension, where the southern tip of the mixed layer front is under frontogenesis. Lagrangian analyses reveal that the vertical shear of geostrophic and subinertial ageostrophic flow below the mixed layer tilts the existing along-isopycnal nitrate gradient of the Kuroshio nutrient stream to form nitrate interleaving structures. This study suggests that the multi-scale combination of (i) the lateral stirring of the Kuroshio nutrient stream by developed mixed layer fronts during fall to winter, (ii) the associated tilting of along-isopycnal nitrate gradient of the nutrient stream by subinertial shear, which forms vertical interleaving structures, and (iii) the strong turbulent diffusion above them, may provide a route to supply nutrients to oligotrophic surface waters on the south side of the Kuroshio Extension.
Nitrate dynamics within a stream-lake network through time and space
NASA Astrophysics Data System (ADS)
Loken, L. C.; Crawford, J. T.; Childress, E. S.; Casson, N. J.; Stanley, E. H.
2014-12-01
Nitrate dynamics in streams are governed by biology, hydrology, and geomorphology, and the ability to parse these drivers apart has improved with the development of accurate high-frequency sensors. By combining a stationary Eulerian and a quasi-Lagrangian sensor platform, we investigated the timing of nitrate flushing and identified locations of elevated biogeochemical cycling along a stream-lake network in Northern Wisconsin, USA. Two years of continuous oxygen, carbon dioxide, and discharge measurements were used to compute gross primary production (GPP) and ecosystem respiration (ER) downstream of a wetland reach of Allequash Creek. Metabolic rates and flow patterns were compared with nitrate concentrations measured every 30 minutes using an optical sensor. Additionally, we floated a sensor array from the headwater spring ponds through a heterogeneous stream reach consisting of wetlands, beaver ponds, forested segments, and two lakes. Two distinct temporal patterns of stream nitrate concentrations were observed. During high flow events such as spring snowmelt and summer rain events, nitrate concentrations increased from ~5 μM (baseflow) to 12 μM, suggesting flushing from catchment sources. During baseflow conditions, nitrate followed a diel cycle with a 0.3-1.0 μM daytime draw down. Daily nitrate reduction was positively correlated with GPP calculated from oxygen and carbon dioxide records. Lastly, spatial analyses revealed lowest nitrate concentrations in the wetland reach, approximately 2-3 μM lower than the upstream spring ponds, and downstream lakes and forested reaches. This snapshot implies greater nitrate removal potential in the wetland reach likely driven by denitrification in organic rich sediments and macrophyte uptake in the open canopy stream segment. Taken together the temporal and spatial results show the dynamics of hydrology, geomorphology, and biology to influence nitrate delivery and variability in ecosystem processing through a stream-lake system. Future ecosystem studies could benefit by including multiple reference frameworks to better assess processes not captured by a single station approach.
NASA Astrophysics Data System (ADS)
Miller, Matthew P.; Tesoriero, Anthony J.; Hood, Krista; Terziotti, Silvia; Wolock, David M.
2017-12-01
The myriad hydrologic and biogeochemical processes taking place in watersheds occurring across space and time are integrated and reflected in the quantity and quality of water in streams and rivers. Collection of high-frequency water quality data with sensors in surface waters provides new opportunities to disentangle these processes and quantify sources and transport of water and solutes in the coupled groundwater-surface water system. A new approach for separating the streamflow hydrograph into three components was developed and coupled with high-frequency nitrate data to estimate time-variable nitrate loads from chemically dilute quick flow, chemically concentrated quick flow, and slowflow groundwater end-member pathways for periods of up to 2 years in a groundwater-dominated and a quick-flow-dominated stream in central Wisconsin, using only streamflow and in-stream water quality data. The dilute and concentrated quick flow end-members were distinguished using high-frequency specific conductance data. Results indicate that dilute quick flow contributed less than 5% of the nitrate load at both sites, whereas 89 ± 8% of the nitrate load at the groundwater-dominated stream was from slowflow groundwater, and 84 ± 25% of the nitrate load at the quick-flow-dominated stream was from concentrated quick flow. Concentrated quick flow nitrate concentrations varied seasonally at both sites, with peak concentrations in the winter that were 2-3 times greater than minimum concentrations during the growing season. Application of this approach provides an opportunity to assess stream vulnerability to nonpoint source nitrate loading and expected stream responses to current or changing conditions and practices in watersheds.
Schilling, K.E.; Wolter, C.F.
2007-01-01
Excessive nitrate-nitrogen (nitrate) loss from agricultural watersheds is an environmental concern. A common conservation practice to improve stream water quality is to retire vulnerable row croplands to grass. In this paper, a groundwater travel time model based on a geographic information system (GIS) analysis of readily available soil and topographic variables was used to evaluate the time needed to observe stream nitrate concentration reductions from conversion of row crop land to native prairie in Walnut Creek watershed, Iowa. Average linear groundwater velocity in 5-m cells was estimated by overlaying GIS layers of soil permeability, land slope (surrogates for hydraulic conductivity and gradient, respectively) and porosity. Cells were summed backwards from the stream network to watershed divide to develop a travel time distribution map. Results suggested that groundwater from half of the land planted in prairie has reached the stream network during the 10 years of ongoing water quality monitoring. The mean travel time for the watershed was estimated to be 10.1 years, consistent with results from a simple analytical model. The proportion of land in the watershed and subbasins with prairie groundwater reaching the stream (10-22%) was similar to the measured reduction of stream nitrate (11-36%). Results provide encouragement that additional nitrate reductions in Walnut Creek are probable in the future as reduced nitrate groundwater from distal locations discharges to the stream network in the coming years. The high spatial resolution of the model (5-m cells) and its simplicity may make it potentially applicable for land managers interested in communicating lag time issues to the public, particularly related to nitrate concentration reductions over time. ?? 2007 Springer-Verlag.
Sebestyen, Stephen D.; Boyer, Elizabeth W.; Shanley, James B.
2009-01-01
[1] In coming decades, higher annual temperatures, increased growing season length, and increased dormant season precipitation are expected across the northeastern United States in response to anthropogenic forcing of global climate. We synthesized long-term stream hydrochemical data from the Sleepers River Research Watershed in Vermont, United States, to explore the relationship of catchment wetness to stream nitrate and DOC loadings. We modeled changes in growing season length and precipitation patterns to simulate future climate scenarios and to assess how stream nutrient loadings respond to climate change. Model results for the 2070–2099 time period suggest that stream nutrient loadings during both the dormant and growing seasons will respond to climate change. During a warmer climate, growing season stream fluxes (runoff +20%, nitrate +57%, and DOC +58%) increase as more precipitation (+28%) and quick flow (+39%) occur during a longer growing season (+43 days). During the dormant season, stream water and nutrient loadings decrease. Net annual stream runoff (+8%) and DOC loading (+9%) increases are commensurate with the magnitude of the average increase of net annual precipitation (+7%). Net annual stream water and DOC loadings are primarily affected by increased dormant season precipitation. In contrast, decreased annual loading of stream nitrate (−2%) reflects a larger effect of growing season controls on stream nitrate and the effects of lengthened growing seasons in a warmer climate. Our findings suggest that leaching of nitrate and DOC from catchment soils will be affected by anthropogenic climate forcing, thereby affecting the timing and magnitude of annual stream loadings in the northeastern United States.
Sebestyen, S.D.; Boyer, E.W.; Shanley, J.B.
2009-01-01
In coming decades, higher annual temperatures, increased growing season length, and increased dormant season precipitation are expected across the northeastern United States in response to anthropogenic forcing of global climate. We synthesized long-term stream hydrochemical data from the Sleepers River Research Watershed in Vermont, United States, to explore the relationship of catchment wetness to stream nitrate and DOC loadings. We modeled changes in growing season length and precipitation patterns to simulate future climate scenarios and to assess how stream nutrient loadings respond to climate change. Model results for the 2070-2099 time period suggest that stream nutrient loadings during both the dormant and growing seasons will respond to climate change. During a warmer climate, growing season stream fluxes (runoff+20%, nitrate +57%, and DOC +58%) increase as more precipitation (+28%) and quick flow (+39%) occur during a longer growing season (+43 days). During the dormant season, stream water and nutrient loadings decrease. Net annual stream runoff (+8%) and DOC loading (+9%) increases are commensurate with the magnitude of the average increase of net annual precipitation (+7%). Net annual stream water and DOC loadings are primarily affected by increased dormant season precipitation. In contrast, decreased annual loading of stream nitrate (-2%) reflects a larger effect of growing season controls on stream nitrate and the effects of lengthened growing seasons in a warmer climate. Our findings suggest that leaching of nitrate and DOC from catchment soils will be affected by anthropogenic climate forcing, thereby affecting the timing and magnitude of annual stream loadings in the northeastern United States. Copyright 2009 by the American Geophysical Union.
Effects of urban stream burial on organic matter dynamics and reach scale nitrate retention - final
Nitrogen (N) retention in streams is an important ecosystem service that may be affected by the widespread burial of streams in stormwater pipes in urban watersheds. We predicted that stream burial suppresses the capacity of streams to retain nitrate (NO3 −) by eliminating primar...
Cadenasso, M L; Pickett, S T A; Groffman, P M; Band, L E; Brush, G S; Galvin, M F; Grove, J M; Hagar, G; Marshall, V; McGrath, B P; O'Neil-Dunne, J P M; Stack, W P; Troy, A R
2008-01-01
Conservation in urban areas typically focuses on biodiversity and large green spaces. However, opportunities exist throughout urban areas to enhance ecological functions. An important function of urban landscapes is retaining nitrogen thereby reducing nitrate pollution to streams and coastal waters. Control of nonpoint nitrate pollution in urban areas was originally based on the documented importance of riparian zones in agricultural and forested ecosystems. The watershed and boundary frameworks have been used to guide stream research and a riparian conservation strategy to reduce nitrate pollution in urban streams. But is stream restoration and riparian-zone conservation enough? Data from the Baltimore Ecosystem Study and other urban stream research indicate that urban riparian zones do not necessarily prevent nitrate from entering, nor remove nitrate from, streams. Based on this insight, policy makers in Baltimore extended the conservation strategy throughout larger watersheds, attempting to restore functions that no longer took place in riparian boundaries. Two urban revitalization projects are presented as examples aimed at reducing nitrate pollution to stormwater, streams, and the Chesapeake Bay. An adaptive cycle of ecological urban design synthesizes the insights from the watershed and boundary frameworks, from new data, and from the conservation concerns of agencies and local communities. This urban example of conservation based on ameliorating nitrate water pollution extends the initial watershed-boundary approach along three dimensions: 1) from riparian to urban land-water-scapes; 2) from discrete engineering solutions to ecological design approaches; and 3) from structural solutions to inclusion of individual, household, and institutional behavior.
Haggard, Brian E.; Masoner, Jason R.; Becker, Carol J.
2003-01-01
Nutrients are one of the primary causes of water-quality impairments in streams, lakes, reservoirs, and estuaries in the United States. The U.S. Environmental Protection Agency has developed regional-based nutrient criteria using ecoregions to protect streams in the United States from impairment. However, nutrient criteria were based on nutrient concentrations measured in large aggregated nutrient ecoregions with little relevance to local environmental conditions in states. The Oklahoma Water Resources Board is using a dichotomous process known as Use Support Assessment Protocols to define nutrient criteria in Oklahoma streams. The Oklahoma Water Resources Board is modifying the Use Support Assessment Protocols to reflect nutrient informa-tion and environmental characteristics relevant to Oklahoma streams, while considering nutrient information grouped by geographic regions based on level III ecoregions and state boundaries. Percentile distributions of median nitrite plus nitrate as nitrogen, total nitrogen, and total phosphorous concentrations were calculated from 563 sites in Oklahoma and 4 sites in Arkansas near the Oklahoma and Arkansas border to facilitate development of nutrient criteria for Oklahoma streams. Sites were grouped into four geographic regions and were categorized into eight stream categories by stream slope and stream order. The 50th percentiles of median nitrite plus nitrate as nitrogen, total nitrogen, and total phosphorus concentrations were greater in the Ozark Highland ecoregion and were less in the Ouachita Mountains ecoregion when compared to other geographic areas used to group sites. The 50th percentiles of median concentrations of nitrite plus nitrate as nitrogen, total nitrogen, and total phosphorus were least in first, second, and third order streams. The 50th percentiles of median nitrite plus nitrate as nitrogen, total nitrogen and total phosphorus concentrations in the Ozark Highland and Ouachita Mountains ecoregions were least in first, second, and third order streams with streams slopes greater than 17 feet per mile. Nitrite plus nitrate as nitrogen and total nitrogen criteria determined by the U.S. Environmental Protection Agency for the Ozark Highland ecoregion were less than the 25th percentiles of median nitrite plus nitrate as nitrogen, total nitrogen, and total phosphorus concentrations in the Ozark Highland ecoregion calculated for this report. Nitrite plus nitrate as nitrogen and total nitrogen criteria developed by the U.S. Environmental Protection Agency for the Ouachita Mountains ecoregion were similar to the 25th percentiles of median nitrite plus nitrate as nitrogen and total nitrogen concentrations in the Ouachita Mountains ecoregion calculated for this report. Nitrate as nitrogen and total phosphorus concentrations currently (2002) used in the Use Support Assessment Protocols for Oklahoma were greater than the 75th percentiles of median nitrite plus nitrate as nitrogen and total phosphorus concentrations calculated for this report.
NASA Astrophysics Data System (ADS)
Sebestyen, S. D.; Shanley, J. B.; Boyer, E. W.; Ohte, N.; Doctor, D. H.; Kendall, C.
2003-12-01
Quantifying sources and transformations of nitrate in headwater catchments is fundamental to understanding the movement of nitrogen to streams. At the Sleepers River Research Watershed in northeastern Vermont (USA), we are using multiple chemical tracer and mixing model approaches to quantify sources and transport of nitrate to streams under varying flow regimes. We sampled streams, lysimeters, and wells at nested locations from the headwaters to the outlet of the 41 ha W-9 watershed under the entire range of flow regimes observed throughout 2002-2003, including baseflow and multiple events (stormflow and snowmelt). Our results suggest that nitrogen sources, and consequently stream nitrate concentrations, are rapidly regenerated during several weeks of baseflow and nitrogen is flushed from the watershed by stormflow events that follow baseflow periods. Both basic chemistry data (anions, cations, & dissolved organic carbon) and isotopic data (nitrate, dissolved organic carbon, and dissolved inorganic carbon) indicate that nitrogen source contributions vary depending upon the extent of saturation in the watershed, the initiation of shallow subsurface water inputs, and other hydrological processes. Stream nitrate concentrations typically peak with discharge and are higher on the falling than the rising limb of the hydrograph. Our data also indicate the importance of terrestrial and aquatic biogeochemical processes, in addition to hydrological connectivity in controlling how nitrate moves from the terrestrial landscape to streams. Our detailed sampling data from multiple flow regimes are helping to identify and quantify the "hot spots" and "hot moments" of biogeochemical and hydrological processes that control nitrogen fluxes in streams.
Miller, Gretchen R; Rubin, Yoram; Mayer, K Ulrich; Benito, Pascual H
2008-01-01
Land application of food-processing waste water occurs throughout California's Central Valley and may be degrading local ground water quality, primarily by increasing salinity and nitrogen levels. Natural attenuation is considered a treatment strategy for the waste, which often contains elevated levels of easily degradable organic carbon. Several key biogeochemical processes in the vadose zone alter the characteristics of the waste water before it reaches the ground water table, including microbial degradation, crop nutrient uptake, mineral precipitation, and ion exchange. This study used a process-based, multi-component reactive flow and transport model (MIN3P) to numerically simulate waste water migration in the vadose zone and to estimate its attenuation capacity. To address the high variability in site conditions and waste-stream characteristics, four food-processing industries were coupled with three site scenarios to simulate a range of land application outcomes. The simulations estimated that typically between 30 and 150% of the salt loading to the land surface reaches the ground water, resulting in dissolved solids concentrations up to sixteen times larger than the 500 mg L(-1) water quality objective. Site conditions, namely the ratio of hydraulic conductivity to the application rate, strongly influenced the amount of nitrate reaching the ground water, which ranged from zero to nine times the total loading applied. Rock-water interaction and nitrification explain salt and nitrate concentrations that exceed the levels present in the waste water. While source control remains the only method to prevent ground water degradation from saline wastes, proper site selection and waste application methods can reduce the risk of ground water degradation from nitrogen compounds.
Groundwater-surface water interaction in the riparian zone of an incised channel, Walnut Creek, Iowa
Schilling, K.E.; Li, Z.; Zhang, Y.-K.
2006-01-01
Riparian zones of many incised channels in agricultural regions are cropped to the channel edge leaving them unvegetated for large portions of the year. In this study we evaluated surface and groundwater interaction in the riparian zone of an incised stream during a spring high flow period using detailed stream stage and hydraulic head data from six wells, and water quality sampling to determine whether the riparian zone can be a source of nitrate pollution to streams. Study results indicated that bank storage of stream water from Walnut Creek during a large storm water runoff event was limited to a narrow 1.6 m zone immediately adjacent to the channel. Nitrate concentrations in riparian groundwater were highest near the incised stream where the unsaturated zone was thickest. Nitrate and dissolved oxygen concentrations and nitrate-chloride ratios increased during a spring recharge period then decreased in the latter portion of the study. We used MODFLOW and MT3DMS to evaluate dilution and denitrification processes that would contribute to decreasing nitrate concentrations in riparian groundwater over time. MT3DMS model simulations were improved with a denitrification rate of 0.02 1/d assigned to the floodplain sediments implying that denitrification plays an important role in reducing nitrate concentrations in groundwater. We conclude that riparian zones of incised channels can potentially be a source of nitrate to streams during spring recharge periods when the near-stream riparian zone is largely unvegetated. ?? 2005 Elsevier B.V. All rights reserved.
Isotopic signals from precipitation and denitrification in nitrate in a northern hardwood forest
NASA Astrophysics Data System (ADS)
Goodale, C. L.; Wexller, S.
2012-12-01
Denitrification can represent an important term in the nitrogen budget of small catchments; however, this process varies greatly over space and time and is notoriously difficult to quantify. Measurements of the natural abundance of stable isotopes of nitrogen and oxygen in dissolved nitrate in stream- and river water can sometimes provide evidence of denitrification, particularly in large river basins or agriculturally impacted catchments. To date, however, this approach has provided little to no evidence of denitrification in catchments in temperate forests. Here, we examined d15N and d18O of nitrate in water samples collected during summer 2011 not only from streams and precipitation, but also from groundwater from the hydrologic reference watershed (W3) drained by Paradise Brook, at the Hubbard Brook Experimental Forest, in the White Mountains, New Hampshire. Despite low nitrate concentrations (< 0.5 to 8.8 uM nitrate) dual-isotopic signals of nitrate sources and nitrogen cycle processes were clearly distinguishable, including sources from atmospheric deposition, and from nitrification of atmospheric ammonium and from or soil organic nitrogen, as well as nitrate affected by soil denitrification. An atmospheric signal from nitrate in precipitation (enriched with 18O) was observed immediately following a precipitation event in mid-July contributing roughly 22% of stream nitrate export on this date. Stream samples the day following this and other storms showed this export of event nitrate to be short-lived. Hillslope piezometers showed low nitrate concentrations and high d15N- and d18O-nitrate values (averaging 12 and 18 per mil, repectively) indicating denitrification, which preferentially removes isotopically light N and O in N gases and leaves isotopically heavy nitrate behind. These samples showed a positive relationship between nitrogen and oxygen isotopic composition with a regression line slope of 0.76 (R2 = 0.68), and an isotope enrichment factor -12.7 per mil for denitrification removal of nitrate in these hillslope soils. The isotopic composition of a time series of samples from three riparian piezometers crossing Paradise Brook shows strong connections between the riparian soil water and the stream, as well as a different dominant source of nitrate in each piezometer. Repeated surveys of stream nitrate show modest positive enrichment in N and O isotopes with a slope between 18O and 15N of 0.96, indicating either in- or near-stream denitrification or mixing between stream and hillslope water bearing a stronger denitrification signal. The dual isotope approach provides detailed information on nitrogen cycling dynamics during the summer in a northern hardwood forested catchment. Together, these observations provide strong isotopic evidence for rapid rates of denitrification during summer in the soils of this small forested catchment.
Tesoriero, Anthony J.
2012-01-01
Groundwater age and water chemistry data along flow paths from recharge areas to streams were used to evaluate the trends and transformations of agricultural chemicals. Results from this analysis indicate that median nitrate recharge concentrations in these agricultural areas have increased markedly over the last 50 years from 4 mg N/L in samples collected prior to 1983 to 7.5 mg N/L in samples collected since 1983. The effect that nitrate accumulation in shallow aquifers will have on drinking water quality and stream ecosystems is dependent on the rate of redox reactions along flow paths and on the age distribution of nitrate discharging to supply wells and streams.
Briand, Cyrielle; Sebilo, Mathieu; Louvat, Pascale; Chesnot, Thierry; Vaury, Véronique; Schneider, Maude; Plagnes, Valérie
2017-01-01
Nitrate content of surface waters results from complex mixing of multiple sources, whose signatures can be modified through N reactions occurring within the different compartments of the whole catchment. Despite this complexity, the determination of nitrate origin is the first and crucial step for water resource preservation. Here, for the first time, we combined at the catchment scale stable isotopic tracers (δ15N and δ18O of nitrate and δ11B) and fecal indicators to trace nitrate sources and pathways to the stream. We tested this approach on two rivers in an agricultural region of SW France. Boron isotopic ratios evidenced inflow from anthropogenic waters, microbiological markers revealed organic contaminations from both human and animal wastes. Nitrate δ15N and δ18O traced inputs from the surface leaching during high flow events and from the subsurface drainage in base flow regime. They also showed that denitrification occurred within the soils before reaching the rivers. Furthermore, this study highlighted the determinant role of the soil compartment in nitrate formation and recycling with important spatial heterogeneity and temporal variability. PMID:28150819
Hydrology and land use in Grand Traverse County, Michigan
Cummings, T.R.; Gillespie, J.L.; Grannemann, N.G.
1990-01-01
Glacial deposits are the sole source of ground-water supplies in Grand Traverse County. These deposits range in thickness from 100 to 900 feet and consist of till, outwash, and materials of lacustrine and eolian origin. In some areas, the deposits fill buried valleys that are 500 feet deep. Sedimentary rocks of Paleozoic age, which underlie the glacial deposits, are mostly shale and are not used for water supply. Of the glacial deposits, outwash and lacustrine sand are the most productive aquifers. Most domestic wells obtain water from sand and gravel at depths ranging from 50 to 150 feet and yield at least 20 gallons per minute. Irrigation, municipal, and industrial wells capable of yielding 250 gallons per minute or more are generally greater than 150 feet deep. At places in the county where moranial deposits contain large amounts of interbedded silt and clay, wells are generally deeper and yields are much lower. Areal variations in the chemical and physical characteristics of ground and surface water are related to land use and chemical inputs to the hydrologic system. Information on fertilizer application, septic-tank discharges, animal wastes, and precipitation indicate that 40 percent of nitrogen input is from precipitation, 6 percent from septic tanks, 14 percent from animal wastes, and 40 percent from fertilizers. Streams and lakes generally have a calcium bicarbonate-type water. The dissolved-solids concentration of streams ranged from 116 to 380 milligrams per liter, and that of lakes, from 47 to 170 milligrams per liter. Water of streams is hard to very hard; water of lakes ranges from soft to hard. The maximum total nitrogen concentration found in streams was 4.4 milligrams per liter. Water of lakes have low nitrogen concentrations; the median nitrate concentration is less than 0.01 milligrams per liter. Pesticides (Parathion and Simazine) were detected in low concentrations at six stream sites; 2,4-D was detected in low concentrations in water of two lakes. Relationships between land use and the yield of dissolved and suspended substances could not be established for most stream basins. Calcium and bicarbonate are the principal dissolved substances in ground water. Dissolved-solids concentrations ranged from 70 to 700 milligrams per liter; the countywide mean concentration is 230 milligrams per liter. The mean nitrate concentration is 1.3 milligrams per liter; about 1.6 percent of the county's ground water has nitrate concentrations that exceed the U.S. Environmental Protection Agency's maximum drinking water level of 10 milligrams per liter. An effect of fertilizer applications on ground-water quality is evident in some parts of the county.
Davis, Jerri V.; Bell, Richard W.
1998-01-01
Nutrient, bacteria, organic carbon, and suspended- sediment samples were collected from 1993-95 at 43 surface-water-quality sampling sites within the Ozark Plateaus National Water- Quality Assessment Program study unit. Most surface-water-quality sites have small or medium drainage basins, near-homogenous land uses (primarily agricultural or forest), and are located predominantly in the Springfield and Salem Plateaus. The water-quality data were analyzed using selected descriptive and statistical methods to determine factors affecting occurrence in streams in the study unit. Nitrogen and phosphorus fertilizer use increased in the Ozark Plateaus study unit for the period 1965-85, but the application rates are well below the national median. Fertilizer use differed substantially among the major river basins and physiographic areas in the study unit. Livestock and poultry waste is a major source of nutrient loading in parts of the study unit. The quantity of nitrogen and phosphorus from livestock and poultry wastes differed substantially among the river basins of the study unit's sampling network. Eighty six municipal sewage-treatment plants in the study unit have effluents of 0.5 million gallons per day or more (for the years 1985-91). Statistically significant differences existed in surface-water quality that can be attributed to land use, physiography, and drainage basin size. Dissolved nitrite plus nitrate, total phosphorus, fecal coliform bacteria, and dissolved organic carbon concentrations generally were larger at sites associated with agricultural basins than at sites associated with forested basins. A large difference in dissolved nitrite plus nitrate concentrations occurred between streams draining basins with agricultural land use in the Springfield and Salem Plateaus. Streams draining both small and medium agricultural basins in the Springfield Plateau had much larger concentrations than their counterparts in the Salem Plateau. Drainage basin size was not a significant factor in affecting total phosphorus, fecal coliform bacteria, or dissolved organic carbon concentrations. Suspended-sediment concentrations generally were small and indicative of the clear water in streams in the Ozark Plateaus. A comparison of the dissolved nitrite plus nitrate, total phosphorus, and fecal coliform data collected at the fixed and synoptic sites indicates that generally the data for streams draining basins of similar physiography, land-use setting, and drainage basin size group together. Many of the variations are most likely the result of differences in percent agricultural land use between the sites being compared or are discharge related. The relation of dissolved nitrite plus nitrate, total phosphorus, and fecal coliform concentration to percent agricultural land use has a strong positive 2 Water-Quality Assessment-Nutrients, Bacteria, Organic Carbon, and Suspended Sediment in Surface Water, 1993-95 correlation, with percent agricultural land use accounting for between 42 and 60 percent of the variation in the observed concentrations.
Fate of acetone in an outdoor model stream with a nitrate supplement, southern Mississippi, U.S.A.
Rathbun, R.E.; Stephens, D.W.; Tai, D.Y.
1991-01-01
The fate of acetone in an outdoor model stream to which nitrate was added as a nutrient supplement was determined. The stream, in southern Mississippi, U.S.A. was 234 m long. Water was supplied to the stream by an artesian well at about 1.21 s-1, resulting in a mean water velocity of about 0.5 m min-1. Acetone was injected continuously for 26 days resulting in concentrations of 20-40 mg l-1. A nitrate solution was injected for 21 days resulting in an instream concentration of about 1.7 mg l-1 at the upstream end of the stream. Rhodamine-WT dye was used to determine the travel time and dispersion characteristics of the stream, and t-butyl alcohol was used to determine the volatilization characteristics. Volatilization controlled the fate of acetone in the model stream. The lack of substantial bacterial degradation of acetone was contrary to expectations based on the results of laboratory degradation studies using model stream water enriched with nitrate. A possible explanation for the lack of significant degradation in the model stream may be the limited 6-h residence time of the acetone in the stream. ?? 1991.
Ranalli, Anthony J.; Macalady, Donald L.
2010-01-01
We reviewed published studies from primarily glaciated regions in the United States, Canada, and Europe of the (1) transport of nitrate from terrestrial ecosystems to aquatic ecosystems, (2) attenuation of nitrate in the riparian zone of undisturbed and agricultural watersheds, (3) processes contributing to nitrate attenuation in riparian zones, (4) variation in the attenuation of nitrate in the riparian zone, and (5) importance of in-stream and hyporheic processes for nitrate attenuation in the stream channel. Our objectives were to synthesize the results of these studies and suggest methodologies to (1) monitor regional trends in nitrate concentration in undisturbed 1st order watersheds and (2) reduce nitrate loads in streams draining agricultural watersheds. Our review reveals that undisturbed headwater watersheds have been shown to be very retentive of nitrogen, but the importance of biogeochemical and hydrological riparian zone processes in retaining nitrogen in these watersheds has not been demonstrated as it has for agricultural watersheds. An understanding of the role of the riparian zone in nitrate attenuation in undisturbed watersheds is crucial because these watersheds are increasingly subject to stressors, such as changes in land use and climate, wildfire, and increases in atmospheric nitrogen deposition. In general, understanding processes controlling the concentration and flux of nitrate is critical to identifying and mapping the vulnerability of watersheds to water quality changes due to a variety of stressors. In undisturbed and agricultural watersheds we propose that understanding the importance of riparian zone processes in 2nd order and larger watersheds is critical. Research is needed that addresses the relative importance of how the following sources of nitrate along any given stream reach might change as watersheds increase in size and with flow: (1) inputs upstream from the reach, (2) tributary inflow, (3) water derived from the riparian zone, (4) groundwater from outside the riparian zone (intermediate or regional sources), and (5) in-stream (hyporheic) processes.
Daniel J. Sobota; Sherri L. Johnson; Stan V. Gregory; Linda R. Ashkenas
2012-01-01
The influence of land use on potential fates of nitrate in stream ecosystems, ranging from denitrification to storage in organic matter, has not been documented extensively. Here, we describe the Pacific Northwest component of Lotic Intersite Nitrogen eXperiment, phase II (LINX II) to examine how land-use setting influences fates of nitrate in streams.
Use of continuous monitoring to assess stream nitrate flux and transformation patterns.
Jones, Christopher; Kim, Sea-Won; Schilling, Keith
2017-01-01
Delivery of nitrogen from farmed fields to the stream network is an ongoing water quality issue in central North America and other parts of the world. Although fertilization and other farming practices have been refined to produce environmental improvements, stemming loss of nitrogen, especially in the soluble nitrate form, is a problem that has seemingly defied solution. The Iowa Nutrient Reduction Strategy is a policy initiative designed to implement conservation and other farm management practices to produce reductions in nitrate loading. The strategy does not focus on how the streams themselves may or may not be processing nitrogen and reducing downstream loading. We used continuous high-frequency nitrate and discharge monitoring over 3 years at two sites separated by 18 km in a low-order, agricultural stream in eastern Iowa to estimate how nitrogen is processed, and whether or not these processes are reducing downstream loading. We conclude that the upstream to downstream nitrate concentration decline between the two sites was not driven by denitrification. These data also show that nitrate concentrations are closely coupled to discharge during periods of adequate moisture, but decoupling of concentration from discharge occurs during dry periods. This decoupling is a possible indicator of in-stream nitrate processing. Finally, nitrate concentrations are likely diluted by water sourced from non-row crop land covers in the lower reaches of the watershed.
Algal productivity and nitrate assimilation in an effluent dominated concrete lined stream
Kent, Robert; Belitz, Kenneth; Burton, Carmen
2005-01-01
This study examined algal productivity and nitrate assimilation in a 2.85 km reach of Cucamonga Creek, California, a concrete lined channel receiving treated municipal wastewater. Stream nitrate concentrations observed at two stations indicated nearly continuous loss throughout the diel study. Nitrate loss in the reach was approximately 11 mg/L/d or 1.0 g/m2/d as N, most of which occurred during daylight. The peak rate of nitrate loss (1.13 mg/l/hr) occurred just prior to an afternoon total CO2 depletion. Gross primary productivity, as estimated by a model using the observed differences in dissolved oxygen between the two stations, was 228 mg/L/d, or 21 g/m2/d as O2. The observed diel variations in productivity, nitrate loss, pH, dissolved oxygen, and CO2indicate that nitrate loss was primarily due to algal assimilation. The observed levels of productivity and nitrate assimilation were exceptionally high on a mass per volume basis compared to studies on other streams; these rates occurred because of the shallow stream depth. This study suggests that concrete‐lined channels can provide an important environmental service: lowering of nitrate concentrations similar to rates observed in biological treatment systems.
Factoring stream turbulence into global assessments of nitrogen pollution.
Grant, Stanley B; Azizian, Morvarid; Cook, Perran; Boano, Fulvio; Rippy, Megan A
2018-03-16
The discharge of excess nitrogen to streams and rivers poses an existential threat to both humans and ecosystems. A seminal study of headwater streams across the United States concluded that in-stream removal of nitrate is controlled primarily by stream chemistry and biology. Reanalysis of these data reveals that stream turbulence (in particular, turbulent mass transfer across the concentration boundary layer) imposes a previously unrecognized upper limit on the rate at which nitrate is removed from streams. The upper limit closely approximates measured nitrate removal rates in streams with low concentrations of this pollutant, a discovery that should inform stream restoration designs and efforts to assess the effects of nitrogen pollution on receiving water quality and the global nitrogen cycle. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
Terziotti, Silvia; Capel, Paul D.; Tesoriero, Anthony J.; Hopple, Jessica A.; Kronholm, Scott C.
2018-03-07
The water quality of the Chesapeake Bay may be adversely affected by dissolved nitrate carried in groundwater discharge to streams. To estimate the concentrations, loads, and yields of nitrate from groundwater to streams for the Chesapeake Bay watershed, a regression model was developed based on measured nitrate concentrations from 156 small streams with watersheds less than 500 square miles (mi2 ) at baseflow. The regression model has three predictive variables: geologic unit, percent developed land, and percent agricultural land. Comparisons of estimated and actual values within geologic units were closely matched. The coefficient of determination (R2 ) for the model was 0.6906. The model was used to calculate baseflow nitrate concentrations at over 83,000 National Hydrography Dataset Plus Version 2 catchments and aggregated to 1,966 total 12-digit hydrologic units in the Chesapeake Bay watershed. The modeled output geospatial data layers provided estimated annual loads and yields of nitrate from groundwater into streams. The spatial distribution of annual nitrate yields from groundwater estimated by this method was compared to the total watershed yields of all sources estimated from a Chesapeake Bay SPAtially Referenced Regressions On Watershed attributes (SPARROW) water-quality model. The comparison showed similar spatial patterns. The regression model for groundwater contribution had similar but lower yields, suggesting that groundwater is an important source of nitrogen for streams in the Chesapeake Bay watershed.
Streamwater nitrate concentrations in six agricultural catchments in Scotland.
Hooda, P S; Moynagh, M; Svoboda, I F; Thurlow, M; Stewart, M; Thomson, M; Anderson, H A
1997-08-01
The concentrations of nitrate-N (NO3-N) in catchment inputs and outputs have been compared and contrasted between 6 farm catchments in Scotland, 3 in the West and 3 in the North-East. Forms of intensive animal farming ranging between beef and dairy cattle, sheep and poultry give different sources for potential NO3-N leakage from the systems. While stream reaches bordered by intensive cereal production give rise to the largest inputs to surface waters, climatic influences result in the more-efficient use of fertilizer- and farm waste-N in the West, and an enhanced potential for N-loss to waters in the cooler North-East, regardless of the N-inputs being considerably lower in the latter region. Although the EC Nitrate Directive limit of 11.3 mg NO3-N 1(-1) was not exceeded, peak values occurring during summer baseflows and autumn soil rewetting were commonly larger than the 'target' maximum concentration of 5.65 mg NO3-N 1-1.
Redox Control For Hanford HLW Feeds VSL-12R2530-1, REV 0
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kruger, A. A.; Matlack, Keith S.; Pegg, Ian L.
2012-12-13
The principal objectives of this work were to investigate the effects of processing simulated Hanford HLW at the estimated maximum concentrations of nitrates and oxalates and to identify strategies to mitigate any processing issues resulting from high concentrations of nitrates and oxalates. This report provides results for a series of tests that were performed on the DM10 melter system with simulated C-106/AY-102 HLW. The tests employed simulated HLW feeds containing variable amounts of nitrates and waste organic compounds corresponding to maximum concentrations proj ected for Hanford HLW streams in order to determine their effects on glass production rate, processing characteristics,more » glass redox conditions, melt pool foaming, and the tendency to form secondary phases. Such melter tests provide information on key process factors such as feed processing behavior, dynamic effects during processing, processing rates, off-gas amounts and compositions, foaming control, etc., that cannot be reliably obtained from crucible melts.« less
Spatial and temporal variation of denitrification in the riparian zone during the hydrological year
NASA Astrophysics Data System (ADS)
Trauth, Nico; Musolff, Andreas; Knöller, Kay; Fleckenstein, Jan H.
2017-04-01
In the riparian zone, where stream water mixes with groundwater, biogeochemical reactions and solute transformations occur which may enhance the self-cleaning mechanisms of aquatic ecosystems. The water exchange and solute transport through the riparian zone is controlled by hydraulic gradients between stream and groundwater and thus varies seasonally and during stream discharge events. In this study, we focus on transport, mixing and the distribution of nitrate in the riparian zone of a gravelly alluvial aquifer with the aim to quantify its denitrification potential during the hydrological year. For this purpose, 25 groundwater wells were drilled along a 2 km stream section of the Selke river, a third-order stream in Germany. From the stream and the wells, water samples were taken 4-weekly over a period of 2 years. Water samples were analyzed to field parameters, major ions, dissolved organic carbon, and N-O isotopes. Results show a strong influence of the stream on the adjacent groundwater, which varies both in time and space. In general, we can distinguish between two endmembers: a) the stream water with low chloride (<30 mg/L) and nitrate (<10 mg/L) concentrations and b) the groundwater in 100m distance to the stream with high chloride (>70 mg/L) and nitrate (>50 mg/L) concentrations. Based on conservatively transported chloride, the mixing of the endmembers can be determined in the riparian zone. Deviations in nitrate concentrations from this mixing model may indicate nitrate degradation by e.g. denitrification. By combining this chloride-nitrate-ratio method with dissolved oxygen data and the isotopic signature of the nitrate molecule, we are able to determine the timing and the location of high denitrification patterns in the riparian aquifer. Highest variability of denitrification occurs over the year in terms of seasonality (temperature-driven) and is temporally fueled by additional organic carbon supply during discharge events.
NASA Astrophysics Data System (ADS)
Hall, S. J.; Hale, R. L.; Baker, M. A.; Bowling, D. R.; Ehleringer, J. R.
2014-12-01
Urban and suburban streams typically receive anthropogenic nitrogen (N) from multiple sources, and their identification and partitioning is a prerequisite for effective water quality management. However, stream N fluxes and sources are often highly variable, limiting the utility of water samples for source identification. Nitrate in perennial streams can provide an important N source for riparian vegetation in semi-arid environments. Thus, riparian plant tissue may integrate the stable isotope composition (δ15N) of stream nitrate over longer timescales and assist in source identification. Here, we tested whether δ15N of riparian plant leaves could provide an effective indicator of spatial variation in N sources across land use gradients spanning wildland to urban ecosystems in Salt Lake City, Utah, and the surrounding Wasatch Range Megapolitan Area. We found that leaf δ15N varied systematically within and among eight streams and rivers (n = 378 leaf samples) consistent with spatial land use variations. Plants from a suburban stream adjacent to homes with septic systems (δ15N = 5.1‰) were highly enriched relative to similar species from an adjacent undeveloped stream (δ15N = -0.7 ‰), suggesting an important contribution of enriched human fecal N to the suburban stream. Plants from a montane stream in a largely undeveloped recreational canyon that permitted off-leash dogs (δ15N = 1.8 ‰) were enriched relative to an adjacent canyon with similar land use that strictly prohibited dogs but had comparable vehicle traffic (δ15N = -0.7 ‰), suggesting the contribution of dog waste to stream N. Plants from urban stream reaches were enriched by 1.3 - 2.8 ‰ relative to upstream wildland reaches, and δ15N increased by 0.2 ‰ per km in the urban streams. Mechanisms leading to this urban enrichment could include leaky municipal sewers, atmospheric N deposition, and/or increased rates of N cycling and gaseous losses. Overall, our results demonstrate the potential utility of riparian plant N isotopes as a simple diagnostic of N source inputs to inform watershed management.
Nitrate retention in a sand plains stream and the importance of groundwater discharge
Robert S. Stelzer; Damion R. Drover; Susan L. Eggert; Maureen A. Muldoon
2011-01-01
We measured net nitrate retention by mass balance in a 700-m upwelling reach of a third-order sand plains stream, Emmons Creek, from January 2007 to November 2008. Surface water and ground-water fluxes of nitrate were determined from continuous records of discharge and from nitrate concentrations based on weekly and biweekly sampling at three surface water stations and...
Smith, R.L.; Böhlke, J.K.; Repert, D.A.; Hart, C.P.
2009-01-01
The extent to which in-stream processes alter or remove nutrient loads in agriculturally impacted streams is critically important to watershed function and the delivery of those loads to coastal waters. In this study, patch-scale rates of in-stream benthic processes were determined using large volume, open-bottom benthic incubation chambers in a nitrate-rich, first to third order stream draining an area dominated by tile-drained row-crop fields. The chambers were fitted with sampling/mixing ports, a volume compensation bladder, and porewater samplers. Incubations were conducted with added tracers (NaBr and either 15N[NO3-], 15N[NO2-], or 15N[NH4+]) for 24-44 h intervals and reaction rates were determined from changes in concentrations and isotopic compositions of nitrate, nitrite, ammonium and nitrogen gas. Overall, nitrate loss rates (220-3,560 ??mol N m-2 h-1) greatly exceeded corresponding denitrification rates (34-212 ??mol N m-2 h-1) and both of these rates were correlated with nitrate concentrations (90-1,330 ??M), which could be readily manipulated with addition experiments. Chamber estimates closely matched whole-stream rates of denitrification and nitrate loss using 15N. Chamber incubations with acetylene indicated that coupled nitrification/denitrification was not a major source of N2 production at ambient nitrate concentrations (175 ??M), but acetylene was not effective for assessing denitrification at higher nitrate concentrations (1,330 ??M). Ammonium uptake rates greatly exceeded nitrification rates, which were relatively low even with added ammonium (3.5 ??mol N m-2 h-1), though incubations with nitrite demonstrated that oxidation to nitrate exceeded reduction to nitrogen gas in the surface sediments by fivefold to tenfold. The chamber results confirmed earlier studies that denitrification was a substantial nitrate sink in this stream, but they also indicated that dissolved inorganic nitrogen (DIN) turnover rates greatly exceeded the rates of permanent nitrogen removal via denitrification. ?? Springer Science+Business Media B.V. 2009.
NITRATE AND NITROUS OXIDE CONCENTRATIONS IN SMALL STREAMS OF THE GEORGIA PIEDMONT
We are measuring dissolved nitrate and nitrous oxide concentrations and related parameters in 17 headwater streams in the South Fork Broad River, Georgia watershed on a monthly basis. The selected small streams drain watersheds dominated by forest, pasture, residential, or mixed...
GEOMORPHIC CONTROLS ON C AND N PROCESSING IN A RESTORED URBAN STREAM; POWER POINT PRESENTATION
Stream channel incision due to hydraulic alteration stemming from urbanization may cause a disconnection between the stream channel and the adjacent floodplain. This disconnection may inhibit removal of nitrate via denitrification and/or stimulate nitrate production through nitr...
Interaction between land use and climate variability amplifies stream nitrate export
We investigated regional effects of urban land use change on nitrate concentrations in approximately 1,000 small streams in Maryland, U.S.A. during record drought and wet years in 2001-2003. We also investigated changes in nitrate-N export during the same time period in 8 intens...
Effect of Flow Depth and Velocity on Nitrate Loss Rates in Natural Channels
Loss rates of nitrate from streams and rivers are governed by movement of the ion from water column to anoxic bed sediments. Quantitative representations of nitrate in streams and rivers have often treated such losses as governed by first-order mechanisms that are invariant with ...
NASA Astrophysics Data System (ADS)
Gilmore, Troy E.; Genereux, David P.; Solomon, D. Kip; Solder, John E.; Kimball, Briant A.; Mitasova, Helena; Birgand, François
2016-03-01
We compared three stream-based sampling methods to study the fate of nitrate in groundwater in a coastal plain watershed: point measurements beneath the streambed, seepage blankets (novel seepage-meter design), and reach mass-balance. The methods gave similar mean groundwater seepage rates into the stream (0.3-0.6 m/d) during two 3-4 day field campaigns despite an order of magnitude difference in stream discharge between the campaigns. At low flow, estimates of flow-weighted mean nitrate concentrations in groundwater discharge ([NO3-]FWM) and nitrate flux from groundwater to the stream decreased with increasing degree of channel influence and measurement scale, i.e., [NO3-]FWM was 654, 561, and 451 µM for point, blanket, and reach mass-balance sampling, respectively. At high flow the trend was reversed, likely because reach mass-balance captured inputs from shallow transient high-nitrate flow paths while point and blanket measurements did not. Point sampling may be better suited to estimating aquifer discharge of nitrate, while reach mass-balance reflects full nitrate inputs into the channel (which at high flow may be more than aquifer discharge due to transient flow paths, and at low flow may be less than aquifer discharge due to channel-based nitrate removal). Modeling dissolved N2 from streambed samples suggested (1) about half of groundwater nitrate was denitrified prior to discharge from the aquifer, and (2) both extent of denitrification and initial nitrate concentration in groundwater (700-1300 µM) were related to land use, suggesting these forms of streambed sampling for groundwater can reveal watershed spatial relations relevant to nitrate contamination and fate in the aquifer.
NASA Astrophysics Data System (ADS)
Steiness, M.; van't Veen, S. G. W.; Jessen, S.; Engesgaard, P. K.
2016-12-01
Riparian zones are critical interfaces between streams and uplands with many of the characteristics for being key areas for nitrate removal. The hydrogeology is a controlling factor for the source, flow paths, magnitude of groundwater discharge to the stream, nitrate loading, and therefore the occurrence of "hot spots" with increased denitrification. A riparian lowland was investigated through field studies (geophysics, hydrogeology), water quality assessment, and flow and reactive transport modelling. One of the objectives was to understand the role of the landscape and hydrogeology on diffusive versus focused groundwater discharge and also nitrate removal. The investigated riparian zone is characterized by diffusive flow of groundwater to the stream from the northern bank (from a maize field) and groundwater upwelling in several places with overland flow to the stream from south (wetland area). Nitrate is effectively removed by pyrite oxidation (as shown by the reactive transport model high sulphate concentrations) on the northern side, whereas the groundwater-fed springs carry up to 74 mg/L nitrate. Groundwater flow modeling shows that upwelling may account for almost 25 % of the flow to the stream. Two other riparian zones were subsequently included and, on the catchment scale, the occurrence of diffusive and focused discharge is found to be common suggesting that riparian zones in this area are only partly effective in removing nitrate.
Lucy A. Rose; Emily M. Elliott; Mary Beth. Adams
2015-01-01
Nitrogen (N) deposition affects forest biogeochemical cycles worldwide, often contributing to N saturation. Using long-term (>30-year) records of stream nitrate (NO3-) concentrations at Fernow Experimental Forest (West Virginia, USA), we classified four watersheds into N saturation stages ranging from Stage 0 (N-...
Nitrogen Uptake and Denitrification in Restored and Unrestored Streams in Urban Maryland, USA
There is growing interest in rates of nitrate uptake and denitrification in restored streams to better understand the effects of restoration on nitrogen processing. This study quantified nitrate uptake in 2 restored and 2 unrestored streams in Baltimore, Maryland, U.S.A. using n...
Nitrate in watersheds: straight from soils to streams?
Sudduth, Elizabeth B.; Perakis, Steven S.; Bernhardt, Emily S.
2013-01-01
Human activities are rapidly increasing the global supply of reactive N and substantially altering the structure and hydrologic connectivity of managed ecosystems. There is long-standing recognition that N must be removed along hydrologic flowpaths from uplands to streams, yet it has proven difficult to assess the generality of this removal across ecosystem types, and whether these patterns are influenced by land-use change. To assess how well upland nitrate (NO3-) loss is reflected in stream export, we gathered information from >50 watershed biogeochemical studies that reported nitrate concentrations ([NO3-]) for stream water and for either upslope soil solution or groundwater NO3- to examine whether stream export of NO3- accurately reflects upland NO3- losses. In this dataset, soil solution and streamwater [NO3-] were correlated across 40 undisturbed forest watersheds, with streamwater [NO3-] typically half (median = 50%) soil solution [NO3-]. A similar relationship was seen in 10 disturbed forest watersheds. However, for 12 watersheds with significant agricultural or urban development, the intercept and slope were both significantly higher than the relationship seen in forest watersheds. Differences in concentration between soil solution or groundwater and stream water may be attributed to biological uptake, microbial processes including denitrification, and/or preferential flow routing. The results of this synthesis are consistent with the hypotheses that undisturbed watersheds have a significant capacity to remove nitrate after it passes below the rooting zone and that land use changes tend to alter the efficiency or the length of watershed flowpaths, leading to reductions in nitrate removal and increased stream nitrate concentrations.
Submergible torch for treating waste solutions and method thereof
Mattus, Alfred J.
1995-01-01
A submergible torch for removing nitrate and/or nitrite ions from a waste solution containing nitrate and/or nitrite ions comprises: a torch tip, a fuel delivery mechanism, a fuel flow control mechanism, a catalyst, and a combustion chamber. The submergible torch is ignited to form a flame within the combustion chamber of the submergible torch. The torch is submerged in a waste solution containing nitrate and/or nitrite ions in such a manner that the flame is in contact with the waste solution and the catalyst and is maintained submerged for a period of time sufficient to decompose the nitrate and/or nitrite ions present in the waste solution.
Submergible torch for treating waste solutions and method thereof
Mattus, Alfred J.
1994-01-01
A submergible torch for removing nitrate and/or nitrite ions from a waste solution containing nitrate and/or nitrite ions comprises: a torch tip, a fuel delivery mechanism, a fuel flow control mechanism, a catalyst, and a combustion chamber. The submergible torch is ignited to form a flame within the combustion chamber of the submergible torch. The torch is submerged in a waste solution containing nitrate and/or nitrite ions in such a manner that the flame is in contact with the waste solution and the catalyst and is maintained submerged for a period of time sufficient to decompose the nitrate and/or nitrite ions present in the waste solution.
High nitrate concentrations in some Midwest United States streams in 2013 after the 2012 drought
Van Metre, Peter C.; Frey, Jeffrey W.; Musgrove, MaryLynn; Nakagaki, Naomi; Qi, Sharon L.; Mahler, Barbara J.; Wieczorek, Michael; Button, Daniel T.
2016-01-01
Nitrogen sources in the Mississippi River basin have been linked to degradation of stream ecology and to Gulf of Mexico hypoxia. In 2013, the USGS and the USEPA characterized water quality stressors and ecological conditions in 100 wadeable streams across the midwestern United States. Wet conditions in 2013 followed a severe drought in 2012, a weather pattern associated with elevated nitrogen concentrations and loads in streams. Nitrate concentrations during the May to August 2013 sampling period ranged from <0.04 to 41.8 mg L−1 as N (mean, 5.31 mg L−1). Observed mean May to June nitrate concentrations at the 100 sites were compared with May to June concentrations predicted from a regression model developed using historical nitrate data. Observed concentrations for 17 sites, centered on Iowa and southern Minnesota, were outside the 95% confidence interval of the regression-predicted mean, indicating that they were anomalously high. The sites with a nitrate anomaly had significantly higher May to June nitrate concentrations than sites without an anomaly (means, 19.8 and 3.6 mg L−1, respectively) and had higher antecedent precipitation indices, a measure of the departure from normal precipitation, in 2012 and 2013. Correlations between nitrate concentrations and watershed characteristics and nitrogen and oxygen isotopes of nitrate indicated that fertilizer and manure used in crop production, principally corn, were the dominant sources of nitrate. The anomalously high nitrate levels in parts of the Midwest in 2013 coincide with reported higher-than-normal nitrate loads in the Mississippi River.
NASA Technical Reports Server (NTRS)
Colon, Guillermo
1998-01-01
The main objectives of this project were the development of a four-compartment electrolytic cell using high selective membranes to remove nitrate from crop residue leachate and convert it to nitric acid, and the development of an six compartment electrodialysis cell to remove selectively sodium from urine wastes. The recovery of both plant inedible biomass and human wastes nutrients to sustain a biomass production system are important aspects in the development of a controlled ecological life support system (CELSS) to provide the basic human needs required for life support during long term space missions. A four-compartment electrolytic cell has been proposed to remove selectively nitrate from crop residue and to convert it to nitric acid, which is actually used in the NASA-KSC Controlled Ecological Life Support System to control the pH of the aerobic bioreactors and biomass production chamber. Human activities in a closed system require large amount of air, water and minerals to sustain life and also generate wastes. Before using human wastes as nutrients, these must be treated to reduce organic content and to remove some minerals which have adverse effects on plant growth. Of all the minerals present in human urine, sodium chloride (NACl) is the only one that can not be used as nutrient for most plants. Human activities also requires sodium chloride as part of the diet. Therefore, technology to remove and recover sodium chloride from wastes is highly desirable. A six-compartment electrodialysis cell using high selective membranes has been proposed to remove and recover NaCl from human urine.
Nitrate Waste Treatment Sampling and Analysis Plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vigil-Holterman, Luciana R.; Martinez, Patrick Thomas; Garcia, Terrence Kerwin
2017-07-05
This plan is designed to outline the collection and analysis of nitrate salt-bearing waste samples required by the New Mexico Environment Department- Hazardous Waste Bureau in the Los Alamos National Laboratory (LANL) Hazardous Waste Facility Permit (Permit).
Spahr, Norman E.; Dubrovsky, Neil M.; Gronberg, JoAnn M.; Franke, O. Lehn; Wolock, David M.
2010-01-01
Hydrograph separation was used to determine the base-flow component of streamflow for 148 sites sampled as part of the National Water-Quality Assessment program. Sites in the Southwest and the Northwest tend to have base-flow index values greater than 0.5. Sites in the Midwest and the eastern portion of the Southern Plains generally have values less than 0.5. Base-flow index values for sites in the Southeast and Northeast are mixed with values less than and greater than 0.5. Hypothesized flow paths based on relative scaling of soil and bedrock permeability explain some of the differences found in base-flow index. Sites in areas with impermeable soils and bedrock (areas where overland flow may be the primary hydrologic flow path) tend to have lower base-flow index values than sites in areas with either permeable bedrock or permeable soils (areas where deep groundwater flow paths or shallow groundwater flow paths may occur). The percentage of nitrate load contributed by base flow was determined using total flow and base flow nitrate load models. These regression-based models were calibrated using available nitrate samples and total streamflow or base-flow nitrate samples and the base-flow component of total streamflow. Many streams in the country have a large proportion of nitrate load contributed by base flow: 40 percent of sites have more than 50 percent of the total nitrate load contributed by base flow. Sites in the Midwest and eastern portion of the Southern Plains generally have less than 50 percent of the total nitrate load contributed by base flow. Sites in the Northern Plains and Northwest have nitrate load ratios that generally are greater than 50 percent. Nitrate load ratios for sites in the Southeast and Northeast are mixed with values less than and greater than 50 percent. Significantly lower contributions of nitrate from base flow were found at sites in areas with impermeable soils and impermeable bedrock. These areas could be most responsive to nutrient management practices designed to reduce nutrient transport to streams by runoff. Conversely, sites with potential for shallow or deep groundwater contribution (some combination of permeable soils or permeable bedrock) had significantly greater contributions of nitrate from base flow. Effective nutrient management strategies would consider groundwater nitrate contributions in these areas. Mean annual base-flow nitrate concentrations were compared to shallow-groundwater nitrate concentrations for 27 sites. Concentrations in groundwater tended to be greater than base-flow concentrations for this group of sites. Sites where groundwater concentrations were much greater than base-flow concentrations were found in areas of high infiltration and oxic groundwater conditions. The lack of correspondingly high concentrations in the base flow of the paired surface-water sites may have multiple causes. In some settings, there has not been sufficient time for enough high-nitrate shallow groundwater to migrate to the nearby stream. In these cases, the stream nitrate concentrations lag behind those in the shallow groundwater, and concentrations may increase in the future as more high-nitrate groundwater reaches the stream. Alternatively, some of these sites may have processes that rapidly remove nitrate as water moves from the aquifer into the stream channel. Partitioning streamflow and nitrate load between the quick-flow and base-flow portions of the hydrograph coupled with relative scales of soil permeability can infer the importance of surface water compared to groundwater nitrate sources. Study of the relation of nitrate concentrations to base-flow index and the comparison of groundwater nitrate concentrations to stream nitrate concentrations during times when base-flow index is high can provide evidence of potential nitrate transport mechanisms. Accounting for the surface-water and groundwater contributions of nitrate is crucial to effective management and remediat
Evaluating sources and processing of nonpoint source nitrate in a small suburban watershed in China
NASA Astrophysics Data System (ADS)
Han, Li; Huang, Minsheng; Ma, Minghai; Wei, Jinbao; Hu, Wei; Chouhan, Seema
2018-04-01
Identifying nonpoint sources of nitrate has been a long-term challenge in mixed land-use watershed. In the present study, we combine dual nitrate isotope, runoff and stream water monitoring to elucidate the nonpoint nitrate sources across land use, and determine the relative importance of biogeochemical processes for nitrate export in a small suburban watershed, Longhongjian watershed, China. Our study suggested that NH4+ fertilizer, soil NH4+, litter fall and groundwater were the main nitrate sources in Longhongjian Stream. There were large changes in nitrate sources in response to season and land use. Runoff analysis illustrated that the tea plantation and forest areas contributed to a dominated proportion of the TN export. Spatial analysis illustrated that NO3- concentration was high in the tea plantation and forest areas, and δ15N-NO3 and δ18O-NO3 were enriched in the step ponds. Temporal analysis showed high NO3- level in spring, and nitrate isotopes were enriched in summer. Study as well showed that the step ponds played an important role in mitigating nitrate pollution. Nitrification and plant uptake were the significant biogeochemical processes contributing to the nitrogen transformation, and denitrification hardly occurred in the stream.
Submergible torch for treating waste solutions and method thereof
Mattus, A.J.
1994-12-06
A submergible torch is described for removing nitrate and/or nitrite ions from a waste solution containing nitrate and/or nitrite ions comprises: a torch tip, a fuel delivery mechanism, a fuel flow control mechanism, a catalyst, and a combustion chamber. The submergible torch is ignited to form a flame within the combustion chamber of the submergible torch. The torch is submerged in a waste solution containing nitrate and/or nitrite ions in such a manner that the flame is in contact with the waste solution and the catalyst and is maintained submerged for a period of time sufficient to decompose the nitrate and/or nitrite ions present in the waste solution. 2 figures.
Water-quality trends in the nation's rivers
Smith, R.A.; Alexander, R.B.; Wolman, M.G.
1987-01-01
Water-quality records from two nationwide sampling networks now permit nationally consistent analysis of long-term water-quality trends at more than 300 locations on major U.S. rivers. Observed trends in 24 measures of water quality for the period from 1974 to 1981 provide new insight into changes in stream quality that occurred during a time of major changes in both terrestrial and atmospheric influences on surface waters. Particularly noteworthy are widespread decreases in fecal bacteria and lead concentrations and widespread increases in nitrate, chloride, arsenic, and cadmium concentrations. Recorded increases in municipal waste treatment, use of salt on highways, and nitrogen fertilizer application, along with decreases in leaded gasoline consumption and regionally variable trends in coal production and combustion during the period appear to be reflected in water-quality changes.Water-quality records from two nationwide sampling networks now permit nationally consistent analysis of long-term water-quality trends at more than 300 locations on major U. S. rivers. Observed trends in 24 measures of water quality for the period from 1974 to 1981 provide new insight into changes in stream quality that occurred during a time of major changes in both terrestrial and atmospheric influences on surface waters. Particularly noteworthy are widespread decreases in fecal bacteria and lead concentrations and widespread increases in nitrate, chloride, arsenic, and cadmium concentrations. Recorded increases in municipal waste treatment, use of salt on highways, and nitrogen fertilizer application, along with decreases in leaded gasoline consumption and regionally variable trends in coal production and combustion during the period appear to be reflected in water-quality changes.
NASA Astrophysics Data System (ADS)
Goodale, C. L.; Thomas, S. A.; Fredriksen, G.; Elliott, E. M.; Flinn, K. M.; Butler, T. J.
2008-12-01
The Susquehanna River provides two-thirds of the annual nitrogen (N) load to the Chesapeake Bay, and atmospheric deposition is a major contributor to the basin's N inputs. Yet, there are few measurements of the retention of atmospheric N in the Upper Susquehanna's forested headwaters. We characterized the amount, form (nitrate, ammonium, and dissolved organic nitrogen), isotopic composition (del18O- and del15N-nitrate), and seasonality of stream N over two years from 8-15 small forested headwater catchments of the Susquehanna Basin. We expected high rates of N retention and seasonal nitrate patterns typical of other seasonally snow-covered catchments: dormant season peaks and growing season minima. Annual nitrate exports were approximately 0.1-0.7 kg N ha-1 y-1, and correlated positively with the percent of catchment free from historical agriculture. DON export averaged 0.6 +/- 0.1 kg N ha-1 y-1. All catchments had high rates of N retention but with atypical seasonal nitrate patterns, consisting of summer peaks, fall crashes, and modest rebounds during the dormant season. The fall nitrate crash coincided with carbon inputs at leaffall, indicating in-stream heterotrophic uptake. Stream del18O-nitrate values indicated microbial nitrification as the dominant source of stream nitrate, with modest contributions directly from precipitation in early stages of snowmelt. Three hypothesized sources of summer nitrate peaks include: delayed release of nitrate flushed to groundwater at snowmelt, weathering of geologic N, and increased net nitrate production. Measurements of shale del15N as well as soil, well-, and springwater nitrate within one catchment point toward a summer increase in net nitrification in surface soils. Rather than plant demand, processes governing the production, retention, and hydrologic transport of nitrate in surface mineral soils may drive the unusual nitrate seasonality in this and other systems, and provide insights on N retention in general.
Sebestyen, Stephen D.; Boyer, Elizabeth W.; Shanley, James B.; Kendall, Carol; Doctor, Daniel H.; Aiken, George R.; Ohte, Nobuhito
2008-01-01
We explored catchment processes that control stream nutrient concentrations at an upland forest in northeastern Vermont, USA, where inputs of nitrogen via atmospheric deposition are among the highest in the nation and affect ecosystem functioning. We traced sources of water, nitrate, and dissolved organic matter (DOM) using stream water samples collected at high frequency during spring snowmelt. Hydrochemistry, isotopic tracers, and end‐member mixing analyses suggested the timing, sources, and source areas from which water and nutrients entered the stream. Although stream‐dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) both originated from leaching of soluble organic matter, flushing responses between these two DOM components varied because of dynamic shifts of hydrological flow paths and sources that supply the highest concentrations of DOC and DON. High concentrations of stream water nitrate originated from atmospheric sources as well as nitrified sources from catchment soils. We detected nitrification in surficial soils during late snowmelt which affected the nitrate supply that was available to be transported to streams. However, isotopic tracers showed that the majority of nitrate in upslope surficial soil waters after the onset of snowmelt originated from atmospheric sources. A fraction of the atmospheric nitrogen was directly delivered to the stream, and this finding highlights the importance of quick flow pathways during snowmelt events. These findings indicate that interactions among sources, transformations, and hydrologic transport processes must be deciphered to understand why concentrations vary over time and over space as well as to elucidate the direct effects of human activities on nutrient dynamics in upland forest streams.
Effects of watershed-scale land use change on stream nitrate concentrations
Schilling, K.E.; Spooner, J.
2006-01-01
The Walnut Creek Watershed Monitoring Project was conducted from 1995 through 2005 to evaluate the response of stream nitrate concentrations to changing land use patterns in paired 5000-ha Iowa watersheds. A large portion of the Walnut Creek watershed is being converted from row crop agriculture to native prairie and savanna by the U.S. Fish and Wildlife Service at the Neal Smith National Wildlife Refuge (NSNWR). Before restoration, land use in both Walnut Creek (treatment) and Squaw Creek (control) watersheds consisted of 70% row crops. Between 1990 and 2005, row crop area decreased 25.4% in Walnut Creek due to prairie restoration but increased 9.2% in Squaw Creek due to Conservation Reserve Program (CRP) grassland conversion back to row crop. Nitrate concentrations ranged between <0.5 to 14 mg L-1 at the Walnut Creek outlet and 2.1 to 15 mg L-1 at the downstream Squaw Creek outlet. Nitrate concentrations decreased 1.2 mg L-1 over 10 yr in the Walnut Creek watershed but increased 1.9 mg L-1 over 10 yr in Squaw Creek. Changes in nitrate were easier to detect and more pronounced in monitored subbasins, decreasing 1.2 to 3.4 mg L-1 in three Walnut Creek subbasins, but increasing up to 8.0 and 11.6 mg L-1 in 10 yr in two Squaw Creek subbasins. Converting row crop lands to grass reduced stream nitrate levels over time in Walnut Creek, but stream nitrate rapidly increased in Squaw Creek when CRP grasslands were converted back to row crop. Study results highlight the close association of stream nitrate to land use change and emphasize that grasslands or other perennial vegetation placed in agricultural settings should be part of a long-term solution to water quality problems. ?? ASA, CSSA, SSSA.
Tracing sources of nitrate in snowmelt runoff using a high-resolution isotopic technique
NASA Astrophysics Data System (ADS)
Ohte, N.; Sebestyen, S. D.; Shanley, J. B.; Doctor, D. H.; Kendall, C.; Wankel, S. D.; Boyer, E. W.
2004-11-01
The denitrifier method to determine the dual isotopic composition (δ15N and δ18O) of nitrate is well suited for studies of nitrogen contributions to streams during runoff events. This method requires only 70 nmol of NO3- and enables high throughput of samples. We studied nitrate sources to a headwater stream during snowmelt by generating a high-temporal resolution dataset at the Sleepers River Research Watershed in Vermont, USA. In the earliest phase of runoff, stream NO3- concentrations were highest and stream discharge, NO3- concentrations, and δ18O of NO3- generally tracked one another during diurnal melting. The isotopic composition of stream NO3- varied in-between atmospheric and groundwater NO3- end members indicating a direct contribution of atmospherically-derived NO3- from the snow pack to the stream. During the middle to late phases of snowmelt, the source shifted toward soil NO3- entering the stream via shallow subsurface flow paths.
GEOMORPHIC CONTROLS ON CARBON AND NITROGEN PROCESSING IN A DEGRADED URBAN STREAM
Elevated nitrate levels in streams and groundwater pose human and ecological threats. Microbial denitrification removes nitrate from groundwater but requires anaerobic (saturated) conditions and adequate supply of dissolved organic carbon from detritus and organic soils. Condit...
Stelzer, R.S.; Bartsch, L.A.; Richardson, W.B.; Strauss, E.A.
2011-01-01
1.Although it is well known that sediments can be hot spots for nitrogen transformation in streams, many previous studies have confined measurements of denitrification and nitrate retention to shallow sediments (<5cm deep). We determined the extent of nitrate processing in deeper sediments of a sand plains stream (Emmons Creek) by measuring denitrification in core sections to a depth of 25cm and by assessing vertical nitrate profiles, with peepers and piezometers, to a depth of 70cm. 2.Denitrification rates of sediment slurries based on acetylene block were higher in shallower core sections. However, core sections deeper than 5cm accounted for 68% of the mean depth-integrated denitrification rate. 3.Vertical hydraulic gradient and vertical profiles of pore water chloride concentration suggested that deep ground water upwelled through shallow sediments before discharging to the stream channel. The results of a two-source mixing model based on chloride concentrations suggested that the hyporheic zone was very shallow (<5cm) in Emmons Creek. 4.Vertical profiles showed that nitrate concentration in shallow ground water was about 10-60% of the nitrate concentration of deep ground water. The mean nitrate concentrations of deep and shallow ground water were 2.17 and 0.73mgNO3-NL-1, respectively. 5.Deep ground water tended to be oxic (6.9mgO2L-1) but approached anoxia (0.8mgO2L-1) after passing through shallow, organic carbon-rich sediments, which suggests that the decline in the nitrate concentrations of upwelling ground water was because of denitrification. 6.Collectively, our results suggest that there is substantial nitrate removal occurring in deep sediments, below the hyporheic zone, in Emmons Creek. Our findings suggest that not accounting for nitrate removal in deep sediments could lead to underestimates of nitrogen processing in streams and catchments. ?? 2011 Blackwell Publishing Ltd.
The contribution of wetlands to stream nitrogen load in the Loch Vale Watershed, Colorado, USA
Jian-hui, Huang; Baron, Jill S.; Binkley, Dan
1996-01-01
We explored the difference between the concentrations of different N forms and other chemical properties between stream water and riparian zone wetland soil water in the Loch Vale Watershed which is located on the eastern slope of the Continental Divide in Rocky Mountain National Park, Colorado, USA. The nitrate N concentration in stream water were significantly higher than in soil water of the three wetlands, while no significant difference appeared in ammonium N. The pH values were higher and conductivity values were lower in stream water than in wetland soil water. However, significant difference also appeared between nitrate N concentrations, pH and conductivity values in the water sampled from different positions of streams. The stream tributary water had higher nitrate N concentrations, higher pH and higher conducitity values. We also conducted experiments to compare the difference between the productivity, total N concentrations in biomass and soil of upper layers. At the end, we concluded that the wetlands distributed along the streams in Loch Vale Watershed had little effect on the nitrogen load of the stream water there.
Stephen D. Sebestyen; Elizabeth W. Boyer; James B. Shanley; Carol Kendall; Daniel H. Doctor; George R. Aiken; Nobuhito Ohte
2008-01-01
We explored catchment processes that control stream nutrient concentrations at an upland forest in northeastern Vermont, USA, where inputs of nitrogen via atmospheric deposition are among the highest in the nation and affect ecosystem functioning. We traced sources of water, nitrate, and dissolved organic matter (DOM) using stream water samples collected at high...
Kimball, Briant A.; Runkel, Robert L.; Walton-Day, Katherine
2008-01-01
Housing development and recreational activity in Emigration Canyon have increased substantially since 1980, perhaps causing an observed decrease in water quality of this northern Utah stream located near Salt Lake City. To identify reaches of the stream that contribute to water-quality degradation, a tracer-injection and synoptic-sampling study was done to quantify mass loading of major ions, trace elements, nitrate, and Escherichia coli (E. coli) to the stream. The resulting mass-loading profiles for major ions and trace elements indicate both geologic and anthropogenic inputs to the stream, principally from tributary and spring inflows to the stream at Brigham Fork, Burr Fork, Wagner Spring, Emigration Tunnel Spring, Blacksmith Hollow, and Killyon Canyon. The pattern of nitrate loading does not correspond to the major-ion and trace-element loading patterns. Nitrate levels in the stream did not exceed water-quality standards at the time of synoptic sampling. The majority of nitrate mass loading can be considered related to anthropogenic input, based on the field settings and trends in stable isotope ratios of nitrogen. The pattern of E. coli loading does not correspond to the major-ion, trace-element, or nitrate loading patterns. The majority of E. coli loading was related to anthropogenic sources based on field setting, but a considerable part of the loading also comes from possible animal sources in Killyon Canyon, in Perkins Flat, and in Rotary Park. In this late summer sampling, E. coli concentrations only exceeded water-quality standards in limited sections of the study reach. The mass-loading approach used in this study provides a means to design future studies and to evaluate the loading on a catchment scale.
Method for processing aqueous wastes
Pickett, John B.; Martin, Hollis L.; Langton, Christine A.; Harley, Willie W.
1993-01-01
A method for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply.
Green Infrastructure Benefits for Communities Managing Nitrate in their Drinking Water Sources
Nitrate in water moving through the “biologically active soil zone” of riparian zones, wetlands and streams may undergo denitrification. Therefore GI techniques such as conservation and restoration of riparian zones, wetlands and streams (daylighting) have the potential to remov...
40 CFR 434.61 - Commingling of waste streams.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Commingling of waste streams. 434.61... STANDARDS Miscellaneous Provisions § 434.61 Commingling of waste streams. Where waste streams from any facility covered by this part are combined for treatment or discharge with waste streams from another...
Two tales of legacy effects on stream nutrient behaviour
NASA Astrophysics Data System (ADS)
Bieroza, M.; Heathwaite, A. L.
2017-12-01
Intensive agriculture has led to large-scale land use conversion, shortening of flow pathways and increased loads of nutrients in streams. This legacy results in gradual build-up of nutrients in agricultural catchments: in soil for phosphorus (biogeochemical legacy) and in the unsaturated zone for nitrate (hydrologic legacy), controlling the water quality in the long-term. Here we investigate these effects on phosphorus and nitrate stream concentrations using high-frequency (10-5 - 100 Hz) sampling with in situ wet-chemistry analysers and optical sensors. Based on our 5 year study, we observe that storm flow responses differ for both nutrients: phosphorus shows rapid increases (up to 3 orders of magnitude) in concentrations with stream flow, whereas nitrate shows both dilution and concentration effects with increasing flow. However, the range of nitrate concentrations change is narrow (up to 2 times the mean) and reflects chemostatic behaviour. We link these nutrient responses with their dominant sources and flow pathways in the catchment. Nitrate from agriculture (with the peak loading in 1983) is stored in the unsaturated zone of the Penrith Sandstone, which can reach up to 70 m depth. Thus nitrate legacy is related to a hydrologic time lag with long travel times in the unsaturated zone. Phosphorus is mainly sorbed to soil particles, therefore it is mobilised rapidly during rainfall events (biogeochemical legacy). The phosphorus stream response will however depend on how well connected is the stream to the catchment sources (driven by soil moisture distribution) and biogeochemical activity (driven by temperature), leading to both chemostatic and non-chemostatic responses, alternating on a storm-to-storm and seasonal basis. Our results also show that transient within-channel storage is playing an important role in delivery of phosphorus, providing an additional time lag component. These results show, that consistent agricultural legacy in the catchment (high historical loads of nutrients) has different effects on nutrients stream responses, depending on their dominant sources and pathways. Both types of time lags, biogeochemical for phosphorus and hydrologic for nitrate, need to be taken into account when designing and evaluating the effectiveness of the agri-environmental mitigation measures.
Effects of urban stream burial on nitrogen uptake and ...
Urbanization has resulted in extensive burial and channelization of headwater streams, yet little is known about impacts on stream ecosystem functions critical for reducing downstream nitrogen pollution. To characterize the biogeochemical impact of stream burial, we measured NO3- uptake, using 15N-NO3- isotope tracer releases, and whole stream metabolism, during four seasons in three paired buried and open streams reaches within the Baltimore Ecosystem Study Long-term Ecological Research Network. Stream burial increased NO3- uptake lengths, by a factor of 7.5 (p < 0.01) and decreased nitrate uptake velocity and areal nitrate uptake rate by factors of 8.2 (p = 0.01) and 9.6 (p < 0.001), respectively. Stream burial decreased gross primary productivity by a factor of 9.2 (p < 0.05) and decreased ecosystem respiration by a factor of 4.2 (p = 0.06). From statistical analysis of Excitation Emissions Matrices (EEMs), buried streams were also found to have significantly less labile dissolved organic matter. Furthermore, buried streams had significantly lower transient storage and water temperatures. Overall, differences in NO3- uptake and metabolism were primarily explained by decreased transient storage and light availability in buried streams. We estimate that stream burial increases daily watershed nitrate export by as much as 500% due to decreased in-stream retention and may considerably decrease carbon export via decreased primary production. These results
NASA Astrophysics Data System (ADS)
Sebestyen, S. D.; Shanley, J. B.; Boyer, E. W.; Kendall, C.
2004-12-01
Our ability to assess how stream nutrient concentrations respond to biogeochemical transformations and stream flow dynamics is often limited by datasets that do not include all flow conditions that occur over event, monthly, seasonal, and yearly time scales. At the Sleepers River Research Watershed in northeastern Vermont, USA, nitrate, DOC (dissolved organic carbon), and major ion concentrations were measured on samples collected over a wide range of flow conditions from summer 2002 through summer 2004. Nutrient flushing occurred at the W-9 catchment and high-frequency sampling revealed critical insights into seasonal and event-scale controls on nutrient concentrations. In this seasonally snow-covered catchment, the earliest stage of snowmelt introduced nitrogen directly to the stream from the snowpack. As snowmelt progressed, the source of stream nitrate shifted to flushing of soil nitrate along shallow subsurface flow paths. In the growing season, nitrogen flushing to streams varied with antecedent moisture conditions. More nitrogen was available to flush to streams when antecedent moisture was lowest, and mobile nitrogen stores in the landscape regenerated under baseflow conditions on times scales as short as 7 days. Leaf fall was another critical time when coupled hydrological and biogeochemical processes controlled nutrient fluxes. With the input of labile organic carbon from freshly decomposing leaves, nitrate concentrations declined sharply in response to in-stream immobilization or denitrification. These high-resolution hydrochemical data from multiple flow regimes are identifying "hot spots" and "hot moments" of biogeochemical and hydrological processes that control nutrient fluxes in streams.
NASA Astrophysics Data System (ADS)
Beaulieu, J. J.; Mayer, P. M.; Kaushal, S.; Pennino, M. J.; Arango, C. P.; Balz, D. A.; Fritz, K. M.; Golden, H. E.; Knightes, C. D.
2012-12-01
Nitrogen (N) retention in stream networks is an important ecosystem service that may be affected by the widespread burial of headwater streams in urban watersheds. Stream burial occurs when segments of a channel are encased in drainage pipe and buried beneath the land surface to facilitate above ground development or stormwater runoff. We predicted that burial suppresses the capacity of streams to retain and transform nitrate, the dominate form of bioavailable N in urban streams, by eliminating primary production, reducing respiration rates, and decreasing water residence time. We tested these predictions by measuring whole-stream nitrate (NO3-) removal rates using 15NO3- isotope tracer releases in reaches that were buried and open to the sunlight in three streams in Cincinnati, Ohio and three streams in Baltimore, Maryland during four seasons. Nitrate uptake lengths in buried reaches (range: 560 - 43,650 m) were 2-98 times greater than open reaches exposed to daylight (range: 85 - 7195 m), indicating that buried reaches were substantially less effective at retaining NO3- than open reaches. Nitrate retention in buried reaches was suppressed by a combination of hydrological and biological processes. High water velocities in buried reaches (buried= 5.8 m/s, open=1.48 m/s) rapidly exported NO3- from the channel, reducing the potential for in-stream NO3- retention. Uptake lengths in the buried reaches were lengthened further by low in-stream biological NO3- demand, as indicated by NO3- uptake velocities 16-fold lower than that of the open reaches. Similarly, buried reaches had lower ecosystem respiration rates than open reaches (buried=1.5g O2/m2/hr, open=4.5g O2/m2/hr), likely due to lower organic matter standing stocks (buried=12 gAFMD/m2, open=48 gAFDM/m2). Biological activity in the buried reaches was further suppressed by the absence of light which precluded photosynthetic activity and the associated assimilative N demand. Overall, our results demonstrate that the combined effects of elevated water velocity and reduced biological activity as a result of stream burial inhibits NO3- retention, exacerbating the export of excess N to downstream water bodies. Future work will scale these results to a river network to assess the cumulative effect of stream burial on watershed NO3- export.
Böhlke, J K; O'Connell, Michael E; Prestegaard, Karen L
2007-01-01
Ground water processes affecting seasonal variations of surface water nitrate concentrations were investigated in an incised first-order stream in an agricultural watershed with a riparian forest in the coastal plain of Maryland. Aquifer characteristics including sediment stratigraphy, geochemistry, and hydraulic properties were examined in combination with chemical and isotopic analyses of ground water, macropore discharge, and stream water. The ground water flow system exhibits vertical stratification of hydraulic properties and redox conditions, with sub-horizontal boundaries that extend beneath the field and adjacent riparian forest. Below the minimum water table position, ground water age gradients indicate low recharge rates (2-5 cm yr(-1)) and long residence times (years to decades), whereas the transient ground water wedge between the maximum and minimum water table positions has a relatively short residence time (months to years), partly because of an upward increase in hydraulic conductivity. Oxygen reduction and denitrification in recharging ground waters are coupled with pyrite oxidation near the minimum water table elevation in a mottled weathering zone in Tertiary marine glauconitic sediments. The incised stream had high nitrate concentrations during high flow conditions when much of the ground water was transmitted rapidly across the riparian zone in a shallow oxic aquifer wedge with abundant outflow macropores, and low nitrate concentrations during low flow conditions when the oxic wedge was smaller and stream discharge was dominated by upwelling from the deeper denitrified parts of the aquifer. Results from this and similar studies illustrate the importance of near-stream geomorphology and subsurface geology as controls of riparian zone function and delivery of nitrate to streams in agricultural watersheds.
Böhlke, J.K.; O'Connell, M. E.; Prestegaard, K.L.
2007-01-01
Ground water processes affecting seasonal variations of surface water nitrate concentrations were investigated in an incised first-order stream in an agricultural watershed with a riparian forest in the coastal plain of Maryland. Aquifer characteristics including sediment stratigraphy, geochemistry, and hydraulic properties were examined in combination with chemical and isotopic analyses of ground water, macropore discharge, and stream water. The ground water flow system exhibits vertical stratification of hydraulic properties and redox conditions, with sub-horizontal boundaries that extend beneath the field and adjacent riparian forest. Below the minimum water table position, ground water age gradients indicate low recharge rates (2-5 cm yr-1) and long residence times (years to decades), whereas the transient ground water wedge between the maximum and minimum water table positions has a relatively short residence time (months to years), partly because of an upward increase in hydraulic conductivity. Oxygen reduction and denitrification in recharging ground waters are coupled with pyrite oxidation near the minimum water table elevation in a mottled weathering zone in Tertiary marine glauconitic sediments. The incised stream had high nitrate concentrations during high flow conditions when much of the ground water was transmitted rapidly across the riparian zone in a shallow oxic aquifer wedge with abundant outflow macropores, and low nitrate concentrations during low flow conditions when the oxic wedge was smaller and stream discharge was dominated by upwelling from the deeper denitrified parts of the aquifer. Results from this and similar studies illustrate the importance of near-stream geomorphology and subsurface geology as controls of riparian zone function and delivery of nitrate to streams in agricultural watersheds. ?? ASA, CSSA, SSSA.
Method for processing aqueous wastes
Pickett, J.B.; Martin, H.L.; Langton, C.A.; Harley, W.W.
1993-12-28
A method is presented for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply. 4 figures.
Schlottmann, Jamie L.; Tanner, Ralph S.; Samadpour, Mansour
2000-01-01
A reconnaissance investigation of hydrology and water quality was conducted to evaluate possible sources of bacteria and nutrient contamination in the Cave Springs Branch basin and the underlying karstic Ozark Plateau aquifer system. Objectives were to: (1) determine the directions of ground-water flow in the basin and determine whether Cave Springs Branch interacts with ground water, (2) compare water quality in Cave Springs Branch with water quality in nearby wells to determine whether the stream is contaminating nearby wells, and (3) determine sources of fecal coliform bacteria and nitrate contamination in Cave Springs Branch and ground water. Potential sources of bacteria and nitrate in the area include cultivated agriculture, cow and horse on pasture, poultry production, households, and wildlife. Presence of fecal coliform and fecal streptococcal bacteria directly indicate fecal contamination and the potential for the presence of other pathogenic organisms in a water supply. Nitrate in drinking water poses health risks and may indicate the presence of additional contaminants. Fecal coliform bacteria colony counts were least in wells, intermediate in the poultry-processing plant wastewater outfall and Honey Creek above the confluence with Cave Springs Branch, and greatest in Cave Springs Branch. Bacteria strains and resistance to antibiotics by some bacteria indicate that livestock may have been sources of some bacteria in the water samples. Multiple antibiotic resistances were not present in the isolates from the water samples, indicating that the bacteria may not be from human or poultry sources. Ribotyping indicates that Escherichia coli bacteria in water samples from the basin were from bird, cow, horse, dog, deer, and human sources. The presence of multiple ribotypes from each type of animal source except bird indicates that most of the bacteria are from multiple populations of source animals. Identifiable sources of bacteria in Cave Springs Branch at the state line were dominantly cow and horse with one ribotype from bird. Escherichia coli was detected in only one well sample. Bacterial ribotypes in water from that upgradient well indicated human and dog feces as sources for bacteria, and that on site wastewater treatment may not always be adequate in these highly permeable soils. Greater concentrations of nitrate in Cave Springs Branch and O'Brien Spring relative to the poultry-processing plant wastewater outfall may be due, in part, to conversion of ammonia from poultry processing plant wastewater. The poultry-processing plant wastewater outfall sample collected in March 2000 contained greater concentrations of ammonia and total organic nitrogen plus ammonia than the spring, stream, and well samples collected during August 1999. Cave Springs Branch and Honey Creek contributed approximately equal loads of nitrogen to Honey Creek below the confluence and the greatest loads of nitrogen were introduced to Cave Springs Branch by the poultry processing plant wastewater outfall and O'Brien Spring. Nitrate concentrations in upgradient well samples ranged from 0.38 to 4.60 milligrams per liter, indicating that there are sources of ground-water nitrogen other than Cave Springs Branch, such as animal waste, fertilizer, or human waste. Nitrogen compounds in water from wells downgradient of Cave Springs Branch may be from Cave Springs Branch, fertilizers, animal waste, or human waste.
Arimoro, Francis O; Osakwe, Emeka I
2006-05-01
The impact of sawmill wood wastes on the distribution of benthic macroinvertebrates at the Sapele section of Benin River, Niger Delta, Nigeria, was investigated from March 2005 to August 2005. A total of 434 individuals were collected by kick-sampling method, representing 21 taxa of benthic macroinvertebrates. Three stations, 1, 2, and 3, were selected from upstream of the site, receiving wood wastes discharge, the impacted site and its down stream, respectively. Among the water quality variables, conductivity, dissolved oxygen, biochemical oxigen demand (BOD(5)), nitrate-nitrogen, phosphate-phosphorus, transparency, and alkalinity were significantly different (P<0.05) among the stations. Orthogonal comparison by Duncan's multiple range test showed that station 2 (the impacted site) was the cause of the difference. More sensitive species such as Ephemeroptera or Plecoptera were completely absent from station 2, the impacted site. Species abundance was similar in station 1 and 3, indicating that the wood wastes must have adversely affected the distribution of these macroinvertebrates, especially the intolerant species. The wood waste discharge not only altered the water chemistry, but also stimulated the abundance of less-sensitive macroinvertebrate species.
Burns, Douglas A.; Boyer, E.W.; Elliott, E.M.; Kendall, C.
2009-01-01
Knowledge of key sources and biogeochemical processes that affect the transport of nitrate (NO3-) in streams can inform watershed management strategies for controlling downstream eutrophication. We applied dual isotope analysis of NO3- to determine the dominant sources and processes that affect NO3- concentrations in six stream/river watersheds of different land uses. Samples were collected monthly at a range of flow conditions for 15 mo during 2004-05 and analyzed for NO3- concentrations, ?? 15NNO3, and ??18ONO3. Samples from two forested watersheds indicated that NO3- derived from nitrification was dominant at baseflow. A watershed dominated by suburban land use had three ??18ONO3 values greater than +25???, indicating a large direct contribution of atmospheric NO 3- transported to the stream during some high flows. Two watersheds with large proportions of agricultural land use had many ??15NNO3 values greater than +9???, suggesting an animal waste source consistent with regional dairy farming practices. These data showed a linear seasonal pattern with a ??18O NO3:??15NNO3 of 1:2, consistent with seasonally varying denitrification that peaked in late summer to early fall with the warmest temperatures and lowest annual streamflow. The large range of ?? 15NNO3 values (10???) indicates that NO 3- supply was likely not limiting the rate of denitrification, consistent with ground water and/or in-stream denitrification. Mixing of two or more distinct sources may have affected the seasonal isotope patterns observed in these two agricultural streams. In a mixed land use watershed of large drainage area, none of the source and process patterns observed in the small streams were evident. These results emphasize that observations at watersheds of a few to a few hundred km2 may be necessary to adequately quantify the relative roles of various NO 3- transport and process patterns that contribute to streamflow in large basins. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.
NASA Astrophysics Data System (ADS)
Malik, Riffat Naseem; Hashmi, Muhammad Zaffar
2017-10-01
Himalayan foothills streams, Pakistan play an important role in living water supply and irrigation of farmlands; thus, the water quality is closely related to public health. Multivariate techniques were applied to check spatial and seasonal trends, and metals contamination sources of the Himalayan foothills streams, Pakistan. Grab surface water samples were collected from different sites (5-15 cm water depth) in pre-washed polyethylene containers. Fast Sequential Atomic Absorption Spectrophotometer (Varian FSAA-240) was used to measure the metals concentration. Concentrations of Ni, Cu, and Mn were high in pre-monsoon season than the post-monsoon season. Cluster analysis identified impaired, moderately impaired and least impaired clusters based on water parameters. Discriminant function analysis indicated spatial variability in water was due to temperature, electrical conductivity, nitrates, iron and lead whereas seasonal variations were correlated with 16 physicochemical parameters. Factor analysis identified municipal and poultry waste, automobile activities, surface runoff, and soil weathering as major sources of contamination. Levels of Mn, Cr, Fe, Pb, Cd, Zn and alkalinity were above the WHO and USEPA standards for surface water. The results of present study will help to higher authorities for the management of the Himalayan foothills streams.
NASA Astrophysics Data System (ADS)
Fovet, Ophélie; Dupas, Rémi; Durand, Patrick; Gascuel-Odoux, Chantal; Gruau, Gérard; Hamon, Yannick; Petitjean, Patrice
2016-04-01
Despite widespread implementation of the nitrate directive in the European Union since the 1990s, the impact on nitrate concentration in rivers is limited (Bouraoui and Grizzetti, 2011). To assess whether this lack of response is due to the long time lags of nitrate transfer or to inadequate programs of measure, long term river and groundwater monitoring data are necessary. This study analyses 15 years of daily nitrate concentration data at the outlet of an intensively farmed catchment in Western France (Kervidy-Naizin, 5 km²) and quarterly nitrate concentration data in the groundwater of two hillslopes equipped with piezometers (Kerroland and Gueriniec) within the same catchment. In this catchment groundwater contribution to annual stream flow is dominant. The objectives of this study were to i) disentangle the influence of interannual climate variability and improvement of agricultural practices (i.e. reduction in N surplus) in the stream chemistry and ii) discuss the reasons for slow catchment recovery from nitrate pollution by comparing trends in groundwater and stream concentrations. Analysis of stream data showed that flow-weighted mean annual concentration at the outlet of the Kervidy-Naizin catchment has decreased by 1.2 mg NO3- l-1 yr-1 from 1999 to 2015. This decrease was slow but significant (p value < 0.01) even though interannual climate variability (i.e. annual cumulated runoff) added noise to the signal: i) deviation in the linear model of nitrate decrease with time was negatively correlated with annual runoff (r = -0.54, p < 0.01) and ii) local minimums in the nitrate time series were coincident with local maximums in the annual runoff. Thus high runoff during wet years led to dilution of the nitrate originating from groundwater, which added variability to the signal of linear decrease in stream concentration. Analysis of groundwater data showed a significant and sharp decrease in nitrate concentration in the Kerroland piezometer transect (4.0 mg NO3- l-1 yr-1) and no significant evolution in the Gueriniec piezometer transect, from 1999 to 2015. This contrasting evolution of groundwater nitrate concentration between the two transects was consistent with data on soil surface nitrogen surplus, with a balanced fertilisation in the Kerroland transect (N surplus close to 0 kg N ha-1 yr-1) and excessive fertilisation in the Gueriniec transect (N surplus > 100 kg N ha-1 yr-1). We conclude that, despite the lags due to pluri annual nitrate transfer through the unsaturated and satured zones in catchments of Western France, significant decrease in nitrate concentration in groundwater and streams should be visible within less than 10 years after implementation of an efficient program of measures. Spatial heterogeneity in the implementation of programs of measures (i.e. reduction of N surplus) is a likely cause of slow, sometimes undetectable, reduction in nitrate concentration. Bouraoui, F., and Grizzetti, B.: Long term change of nutrient concentrations of rivers discharging in European seas, The Science of the total environment, 409, 4899-4916, 10.1016/j.scitotenv.2011.08.015, 2011.
Bacterial degradation of acetone in an outdoor model stream
Rathbun, R.E.; Stephens, D.W.; Tai, D.Y.
1993-01-01
Diurnal variations of the acetone concentration in an outdoor model stream were measured with and without a nitrate supplement to determine if the nitrate supplement would stimulate bacterial degradation of the acetone. Acetone loss coefficients were computed from the diurnal data using a fitting procedure based on a Lagrangian particle model. The coefficients indicated that bacterial degradation of the acetone was occurring in the downstream part of the stream during the nitrate addition. However, the acetone concentrations stabilized at values considerably above the limit of detection for acetone determination, in contrast to laboratory respirometer studies where the acetone concentration decreased rapidly to less than the detection limit, once bacterial acclimation to the acetone had occurred. One possible explanation for the difference in behavior was the limited 6-hour residence time of the acetone in the model stream.
Denitrification in sediments from the hyporheic zone adjacent to a small forested stream
Duff, J.H.; Triska, F.J.
1990-01-01
Denitrifying potentials increased with increasing distance from the stream channel. Dissolved oxygen was 100% of the concentration expected in equilibrium with the atmosphere in water obtained from monitoring wells immediately adjacent to the stream but was as low as 7% of the expected value in water 11.4 m inland. Both nitrate and dissolved organic carbon decreased over summer in wells at the base of the alder-forested slope. A 48-h injection of nitrate-amended stream water into hyporheic water 8.4 m inland stimulated nitrous oxide production in the presence of acetylene. Nitrous oxide was generated as nitrate and acetylene were co-transported to a well 13 m down-gradient. Acetylene-block experiments coupled with the chemistry data suggest that denitrification can modify the chemistry of water during passage through the hyporheic zone. -from Authors
CONTINUOUS PRECIPITATION METHOD FOR CONVERSION OF URANYL NITRATE TO URANIUM HEXAFLUORIDE
Reinhart, G.M.; Collopy, T.J.
1962-11-13
A continuous precipitation process is given for converting a uranyl nitrate solution to uranium tetrafluoride. A stream of the uranyl nitrate solution and a stream of an aqueous ammonium hydroxide solution are continuously introduced into an agitated reaction zone maintained at a pH of 5.0 to 6.5. Flow rates are adjusted to provide a mean residence time of the resulting slurry in the reaction zone of at least 30 minutes. After a startup period of two hours the precipitate is recovered from the effluent stream by filtration and is converted to uranium tetrafluoride by reduction to uranium dioxide with hydrogen and reaction of the uranium dioxide with anhydrous hydrogen fluoride. (AEC)
Abstract: Increasing nitrate levels in streams and ground water are harmful to both the environment and humans. Denitrification, a natural process performed by microbes, removes nitrate from ground water when there is an adequate amount of organic matter present as well as low le...
NASA Astrophysics Data System (ADS)
Lohse, K. A.; Sanderman, J.; Amundson, R. G.
2005-12-01
Patterns of precipitation and runoff in California are changing and likely to influence the structure and functioning of watersheds. Studies have demonstrated that hydrologic flushing during seasonal transitions in Mediterranean ecosystems can exert a strong control on nitrogen (N) export, yet few studies have examined the influence of different hydrological flow paths on rates and forms of nitrogen (N) losses. Here we illuminate the influence of variations in precipitation and hydrological pathways on the rate and form of N export along a toposequence of a well-characterized Mediterranean catchment in northern California. As a part of a larger study examining particulate and dissolved carbon loss, we analyzed seasonal patterns of dissolved organic nitrogen (DON), nitrate and ammonium concentrations in rainfall, throughfall, matrix and preferential flow, and stream samples over the course of one water year. We also analyzed seasonal soil N dynamics along this toposequence. During the transition to the winter rain season, but prior to any soil water displacement to the stream, DON and nitrate moved through near-surface soils as preferential flow. Once hillslope soils became saturated, saturated subsurface flow flushed nitrate from the hollow resulting in high stream nitrate/DON concentrations. Between storms, stream nitrate/DON concentrations were lower and appeared to reflect deep subsurface water flow chemistry. During the transition to the wet season, rates of soil nitrate production were high in the hollow relative to the hillslope soils. In the spring, these rates systematically declined as soil moisture decreased. Results from our study suggest seasonal fluctuations in soil moisture control soil N cycling and seasonal changes in the hydrological connection between hillslope soils and streams control the seasonal production and export of hydrologic N.
Guidelines for land application of CAFO waste may not be sufficient to prevent ground water contamination by nitrate. A case study is presented illustrating the problem for one field site disposing of swine waste. Data are discussed in context with documented land application ...
Method for solidifying liquid radioactive wastes
Berreth, Julius R.
1976-01-01
The quantity of nitrous oxides produced during the solidification of liquid radioactive wastes containing nitrates and nitrites can be substantially reduced by the addition to the wastes of a stoichiometric amount of urea which, upon heating, destroys the nitrates and nitrites, liberating nontoxic N.sub.2, CO.sub.2 and NH.sub.3.
A study of dissolved organic carbon and nitrate export in Catskill Mountain watersheds
NASA Astrophysics Data System (ADS)
Son, K.; Moore, K. E.; Lin, L.; Schneiderman, E. M.; Band, L. E.
2016-12-01
Watersheds in the Catskill Mountain region of New York State have historically experienced soil and stream acidification due to deposition of acidic compounds created from atmospheric SO2 and NOx. Recent studies in this region, and elsewhere in North America and Europe, have shown increases in dissolved organic carbon (DOC) in streams and lakes. Watersheds in the Catskills are the major source of drinking water for New York City and other communities in the region. Due to use of chlorine for disinfection, there is potential for the increase in DOC to lead to increased levels of disinfection byproducts in treated drinking water. Therefore, developing an improved understanding of the sources, fate and transport mechanisms, and export patterns for nitrate and DOC is important for informing watershed and water supply management. In this study, we analyzed the relationships between watershed characteristics, nitrate, and DOC for 12 gauged streams in the Neversink River watershed. Watershed characteristics included topography (elevation, slope, topographic wetness index), vegetation (leaf area index, species composition), soil (soil hydraulic parameters, soil carbon, wetland soil), atmospheric deposition (SO2, NOx), and climate (precipitation, temperature). Our preliminary analysis showed that both watershed slope and baseflow ratio are negatively correlated with annual median DOC concentration. At Biscuit Brook in the Neversink watershed, annual precipitation explained about 25% of annual DOC median concentration. DOC concentration was highly correlated with storm runoff in spring, summer, and fall, but stream nitrate concentration was weakly correlated with storm runoff in most seasons except summer when it was highly correlated with baseflow. We also applied a process-based ecohydrologic model (Regional Hydrologic Ecologic System Simulation, RHESSys) to the Biscuit Brook watershed to explore sources of nitrate and DOC and their movement within the watershed. We expect that this study will increase our understanding of how, when, and where DOC and nitrate are stored and transported to streams, as well as give insights into the key controls on nitrate and DOC processes in Catskill Mountain watersheds.
Mast, M. Alisa; Clow, David W.; Baron, Jill S.; Wetherbee, Gregory A.
2014-01-01
Long-term patterns of stream nitrate export and atmospheric N deposition were evaluated over three decades in Loch Vale, a high-elevation watershed in the Colorado Front Range. Stream nitrate concentrations increased in the early 1990s, peaked in the mid-2000s, and have since declined by over 40%, coincident with trends in nitrogen oxide emissions over the past decade. Similarities in the timing and magnitude of N deposition provide evidence that stream chemistry is responding to changes in atmospheric deposition. The response to deposition was complicated by a drought in the early 2000s that enhanced N export for several years. Other possible explanations, including forest disturbance, snow depth, or permafrost melting, could not explain patterns in N export. Our results show that stream chemistry responds rapidly to changes in N deposition in high-elevation watersheds, similar to the response observed to changes in sulfur deposition.
Quantifying nutrient sources in an upland catchment using multiple chemical and isotopic tracers
NASA Astrophysics Data System (ADS)
Sebestyen, S. D.; Boyer, E. W.; Shanley, J. B.; Doctor, D. H.; Kendall, C.; Aiken, G. R.
2006-12-01
To explore processes that control the temporal variation of nutrients in surface waters, we measured multiple environmental tracers at the Sleepers River Research Watershed, an upland catchment in northeastern Vermont, USA. Using a set of high-frequency stream water samples, we quantified the variation of nutrients over a range of stream flow conditions with chemical and isotopic tracers of water, nitrate, and dissolved organic carbon (DOC). Stream water concentrations of nitrogen (predominantly in the forms of nitrate and dissolved organic nitrogen) and DOC reflected mixing of water contributed from distinct sources in the forested landscape. Water isotopic signatures and end-member mixing analysis revealed when solutes entered the stream from these sources and that the sources were linked to the stream by preferential shallow subsurface and overland flow paths. Results from the tracers indicated that freshly-leached, terrestrial organic matter was the overwhelming source of high DOC concentrations in stream water. In contrast, in this region where atmospheric nitrogen deposition is chronically elevated, the highest concentrations of stream nitrate were attributable to atmospheric sources that were transported via melting snow and rain fall. These findings are consistent with a conceptual model of the landscape in which coupled hydrological and biogeochemical processes interact to control stream solute variability over time.
Role of monitoring in stream restoration
Hydrology and dissolved organic carbon availability dictate nitrate dynamics in urban streams. So to improve N uptake, restore streams to: • Slow down stream flow • Add organic carbon • Reconnect floodplain hydrology and riparian zones
Dynamics of nitrate production and removal as a function of residence time in the hyporheic zone
Jay P. Zarnetske; Roy Haggerty; Steven M. Wondzell; Michelle A. Baker
2011-01-01
Biogeochemical reactions associated with stream nitrogen cycling, such as nitrification and denitrification, can be strongly controlled by water and solute residence times in the hyporheic zone (HZ). We used a whole-stream steady state 15N-Iabeled nitrate and conservative tracer addition to investigate the spatial and temporal physiochemical...
Pathways for nitrate release from an alpine watershed: Determination using δ15N and δ18O
Campbell, Donald H.; Kendall, Carol; Chang, Cecily C.Y.; Silva, Steven R.; Tonnessen, Kathy A.
2002-01-01
Snowpack, snowmelt, precipitation, surface water, and groundwater samples from the Loch Vale watershed in Colorado were analyzed for δ15N and δ18O of nitrate to determine the processes controlling the release of atmospherically deposited nitrogen from alpine and subalpine ecosystems. Although overlap was found between the δ15N(NO3) values for all water types (−4 to +6‰), the δ18O(NO3) values for surface water and groundwater (+10 to +30‰) were usually distinct from snowpack, snowmelt, and rainfall values (+40 to +70‰). During snowmelt, δ18O(NO3) indicated that about half of the nitrate in stream water was the product of microbial nitrification; at other times that amount was greater than half. Springs emerging from talus deposits had high nitrate concentrations and a seasonal pattern in δ18O(NO3) that was similar to the pattern in the streams, indicating that shallow groundwater in talus deposits is a likely source of stream water nitrate. Only a few samples of surface water and groundwater collected during early snowmelt and large summer rain events had isotopic compositions that indicated most of the nitrate came directly from atmospheric deposition with no biological assimilation and release. This study demonstrates the value of the nitrate double‐isotope technique for determining nitrogen‐cycling processes and sources of nitrate in small, undisturbed watersheds that are enriched with inorganic nitrogen.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elicio, Andy U.
My ERM 593 applied project will provide guidance for the Los Alamos National Laboratory Waste Stream Profile reviewer (i.e. RCRA reviewer) in regards to Reviewing and Approving a Waste Stream Profile in the Waste Compliance and Tracking System. The Waste Compliance and Tracking system is called WCATS. WCATS is a web-based application that “supports the generation, characterization, processing and shipment of LANL radioactive, hazardous, and industrial waste.” The LANL generator must characterize their waste via electronically by filling out a waste stream profile (WSP) in WCATS. Once this process is completed, the designated waste management coordinator (WMC) will perform amore » review of the waste stream profile to ensure the generator has completed their waste stream characterization in accordance with applicable state, federal and LANL directives particularly P930-1, “LANL Waste Acceptance Criteria,” and the “Waste Compliance and Tracking System User's Manual, MAN-5004, R2,” as applicable. My guidance/applied project will describe the purpose, scope, acronyms, definitions, responsibilities, assumptions and guidance for the WSP reviewer as it pertains to each panel and subpanel of a waste stream profile.« less
Isotopic signals of denitrification in a northern hardwood forested catchment
NASA Astrophysics Data System (ADS)
Wexler, Sarah; Goodale, Christine
2013-04-01
Water samples from streams, groundwater and precipitation were collected during summer from the hydrologic reference watershed (W3) at Hubbard Brook Experimental Forest in the White Mountains, New Hampshire, and analysed for d15N-NO3 and d18O-NO3. Despite very low nitrate concentrations (<0.5 to 8.8 uM NO3-) dual-isotopic signals of sources and processes were clearly distinguishable. The isotopic composition of nitrate from shallow groundwater showed evidence of dual isotopic fractionation in line with denitrification, with a positive relationship between nitrogen and oxygen isotopic composition, a regression line slope of 0.76 (r2 = 0.68), and an empirical isotope enrichment factor of ɛP-S 15N-NO3 -12.7%. The isotopic composition of riparian groundwater nitrate from time-series samples showed variation in processes over a small spatial scale. The expected isotopic composition of nitrate sources in the watershed was used to distinguish nitrate in rain and nitrate from nitrification of both rainfall ammonium and ammonium from mineralised soil organic nitrogen. Evidence of oxygen exchange with water during nitrification was seen in the isotopic composition of stream and shallow groundwater nitrate. The isotopic composition of streamwater nitrate following a period of storms indicated that 25% of nitrate in the streamwater was of atmospheric origin. This suggests rapid infiltration of rainfall via vertical bypass flow to the saturated zone, enabling transport of atmospheric nitrate to the stream channels. Across the Hubbard Brook basin, the isotopic composition of nitrate from paired samples from watersheds 4-7 indicated a switch between a nitrification and assimilation dominated system, to a system influenced by rainfall nitrogen inputs and denitrification. The dual isotope approach has revealed evidence of denitrification of nitrate from different sources at low concentrations at Hubbard Brook during summer. This isotopic evidence deepens our understanding of the significance and spatial variability of denitrification in environments with low levels of nitrate, represented by this northern hardwood forested catchment.
Managing and Transforming Waste Streams – A Tool for Communities
The Managing and Transforming Waste Streams Tool features 100 policy and program options communities can pursue to increase rates of recycling, composting, waste reduction, and materials reuse across waste stream generators.
Mahler, Barbara J.; Musgrove, MaryLynn; Sample, Thomas L.; Wong, Corinne I.
2011-01-01
The Barton Springs zone, which comprises the Barton Springs segment of the Edwards aquifer and the watersheds to the west that contribute to its recharge, is in south-central Texas, an area with rapid growth in population and increasing amounts of land area affected by development. During November 2008-March 2010, an investigation of factors affecting the fate and transport of nutrients and bacteria in the Barton Springs zone was conducted by the U.S. Geological Survey (USGS), in cooperation with the Texas Commission on Environmental Quality. The primary objectives of the study were to characterize occurrence of nutrients and bacteria in the Barton Springs zone under a range of flow conditions; to improve understanding of the interaction between surface-water quality and groundwater quality; and to evaluate how factors such as streamflow variability and dilution affect the fate and transport of nutrients and bacteria in the Barton Springs zone. The USGS collected and analyzed water samples from five streams (Barton, Williamson, Slaughter, Bear, and Onion Creeks), two groundwater wells (Marbridge and Buda), and the main orifice of Barton Springs in Austin, Texas. During the period of the study, during which the hydrologic conditions transitioned from exceptional drought to wetter than normal, water samples were collected routinely (every 3 to 4 weeks) from the streams, wells, and spring and, in response to storms, from the streams and spring. All samples were analyzed for major ions, nutrients, the bacterium Escherichia coli, and suspended sediment. During the dry period, the geochemistry of groundwater at the two wells and at Barton Springs was dominated by flow from the aquifer matrix and was relatively similar and unchanging at the three sites. At the onset of the wet period, when the streams began to flow, the geochemistry of groundwater samples from the Marbridge well and Barton Springs changed rapidly, and concentrations of most major ions and nutrients and densities of Escherichia coli became more similar to those of samples from the streams relative to concentrations and densities during the dry period. Geochemical modeling indicated that the proportion of Barton Springs discharge composed of stream recharge increased from about 0-8 percent during the dry period to about 80 percent during the wet period. The transition from exceptional drought to wetter-than-normal conditions resulted in a number of marked changes that highlight factors affecting the fate and transport of nutrients and bacteria and the strong influence of stream recharge on water quality in the Barton Springs segment of the Edwards aquifer and had a pronounced effect on the fate of nitrogen species. Organic nitrogen loaded to and stored in soils during the dry period was nitrified to nitrate when the soils were rewetted, resulting in elevated concentrations of nitrate plus nitrite in streams as these constituents were progressively leached during continued wet weather. Estimated mean monthly loads of organic nitrogen and nitrate plus nitrite in stream recharge and Barton Springs discharge, which were relatively low and constant during the dry period, increased during the wet period. Loads of organic nitrogen, on average, were about six times greater in stream recharge than in Barton Springs discharge, indicating that organic nitrogen likely was being converted to nitrate within the aquifer. Loads of total nitrogen (organic nitrogen plus ammonia and nitrate plus nitrite) in stream recharge (162 kilograms per day) and in Barton Springs discharge (157 kilograms per day) for the period of the investigation were not significantly different. Dilution was not an important factor affecting concentrations of nitrate plus nitrite in the streams or in Barton Springs during the period of this investigation: Concentrations of nitrate plus nitrite did not decrease in streams with increasing stream discharge, and nitrate plus nitrite concentrations measured at Barton
Bauer, Daniel P.; Steele, Timothy Doak; Anderson, Richard D.
1978-01-01
An analysis of the waste-load assimilative capacity of the Yampa River from Steamboat Springs to Hayden, Colo., a distance of 38 miles, was made during September 1975 to obtain information on the effects of projected waste loadings on this stream reach. Simulations of effects of waste loadings on streamflow quality were made using a steady-state water-quality model. The simulations were based on 7-day low-flow values with a 10-year recurrence interval and population projections for 2010. Model results for December and September streamflow conditions indicated that the recommended 1978 Colorado and 1976 U.S. Environmental Protection Agency water-quality standard of 0.02 milligram per liter for nonionized ammonia concentration would be exceeded. Model simulations also included the effect of a flow augmentation of 20 cubic feet per second from a proposed upstream reservoir. The permissible ammonia loading in the study reach could be increased approximately 25 percent with this amount of flow augmentation. Simulations of concentrations of dissolved oxygen, fecal-coliform bacteria, and nitrate nitrogen indicated that the State 's water-quality goals proposed for 1978, 1983, or 1985 would not be exceeded. (Woodard-USGS)
NASA Technical Reports Server (NTRS)
Parrish, Clyde F.; Barile, Ronald G.; Gamble, Paul H.; Lueck, Dale E.; Young, Rebecca C.
1995-01-01
A new emissions control system for the oxidizer scrubbers that eliminates the current oxidizer liquor waste and lowers the NO(x) emissions is described. Since fueling and deservicing spacecraft constitute the primary operations in which environmental emissions occur, this will eliminate the second largest waste stream at KSC. This effort is in accord with Executive Order No. 12856 (Federal Compliance with Right-to-Know Laws and Pollution Prevention Requirements, data 6 Aug. 1993) and Executive Order No. 12873 (Federal Acquisition, Recycling, and Waste Prevention, dated 20 Oct. 1993). A recent study found that the efficiencies of the oxidizer scrubbers during normal operations ranged from 70 percent to 99 percent. The new scrubber liquor starts with 1% hydrogen peroxide at a pH of 7 and the process control system adds hydrogen peroxide and potassium hydroxide to the scrubber liquor to maintain those initial conditions. The result is the formation of a solution of potassium nitrate, which is sold as a fertilizer. This report describes the equipment and procedures used to monitor and control the conversion of the scrubber liquor to fertilizer, while reducing the scrubber emissions.
The effect of beaver ponds on water quality in rural coastal plain streams
Bason, Christopher W.; Kroes, Daniel; Brinson, Mark M.
2017-01-01
We compared water-quality effects of 13 beaver ponds on adjacent free-flowing control reaches in the Coastal Plain of rural North Carolina. We measured concentrations of nitrate, ammonium, soluble reactive phosphorus (SRP), and suspended sediment (SS) upstream and downstream of paired ponds and control reaches. Nitrate and SS concentrations decreased, ammonium concentrations increased, and SRP concentrations were unaffected downstream of the ponds and relative to the control reaches. The pond effect on nitrate concentration was a reduction of 112 ± 55 μg-N/L (19%) compared to a control-reach—influenced reduction of 28 ± 17 μg-N/L. The pond effect on ammonium concentration was an increase of 9.47 ± 10.9 μg-N/L (59%) compared to the control-reach—influenced reduction of 1.49 ± 1.37 μg-N/L. The pond effect on SS concentration was a decrease of 3.41 ± 1.68 mg/L (40%) compared to a control-reach—influenced increase of 0.56 ± 0.27 mg/L. Ponds on lower-order streams reduced nitrate concentrations by greater amounts compared to those in higher-order streams. Older ponds reduced SS concentrations by greater amounts compared to younger ponds. The findings of this study indicate that beaver ponds provide water-quality benefits to rural Coastal Plain streams by reducing concentrations of nitrate and suspended sediment.
NASA Astrophysics Data System (ADS)
Irawan, D. E.; Sulistyawati, E.; Midori, A. A.; Faisal, B.; Darul, A.; Agustin, A.
2018-04-01
In most Asia countries, the riverbank area is mostly inhabited by the low-income population, due to the shortage of formal housing. Most of the settlement areas are not equipped with proper sanitation system. Hence, the water quality gets lower over time with the increasing number of inhabitants around the riverbank. Th water quality gets worse with the close hydrological connection between surface water and the shallow groundwater. We compare the state of water quality based on our three case studies: Cikapundung Bandung, Kanal Banjir Timur Semarang, and Cisadane Tangerang. In each location, we gathered the following data: water level measurements, water flow mapping, and water quality samples. Then we make maps to evaluate existing status. The comparison will be made based on the physical and chemical properties that we get from the field. On all locations, we find very close interactions between surface water and groundwater. The hydrological connections are different in direction from upstream to downstream: gaining stream, combined stream or perched stream, and losing stream. However different river gradient gives a slightly different length of hydrological zonations. All samples show a high bicarbonate from rain water, the dissolution of carbonate minerals from the rocks and soils, and also organic species from microbial activities, which induced by domestic wastes. However, we need to make a carbonate balance calculation to break down the components. All samples also have high nitrate and nitrite concentration which come from domestic waste along the river and fertilizer from the rice fields upstream (only in Cikapundung river). For further research, we suggest chemical modeling to break up the contamination components and possible sources.
Options Assessment Report: Treatment of Nitrate Salt Waste at Los Alamos National Laboratory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robinson, Bruce Alan; Stevens, Patrice Ann
2015-12-17
This report documents the methodology used to select a method of treatment for the remediated nitrate salt (RNS) and unremediated nitrate salt (UNS) waste containers at Los Alamos National Laboratory (LANL). The method selected should treat the containerized waste in a manner that renders the waste safe and suitable for transport and final disposal in the Waste Isolation Pilot Plant (WIPP) repository, under specifications listed in the WIPP Waste Acceptance Criteria (DOE/CBFO, 2013). LANL recognizes that the results must be thoroughly vetted with the New Mexico Environment Department (NMED) and that a modification to the LANL Hazardous Waste Facility Permitmore » is a necessary step before implementation of this or any treatment option. Likewise, facility readiness and safety basis approvals must be received from the Department of Energy (DOE). This report presents LANL’s preferred option, and the documentation of the process for reaching the recommended treatment option for RNS and UNS waste, and is presented for consideration by NMED and DOE.« less
Method for calcining nuclear waste solutions containing zirconium and halides
Newby, Billie J.
1979-01-01
A reduction in the quantity of gelatinous solids which are formed in aqueous zirconium-fluoride nuclear reprocessing waste solutions by calcium nitrate added to suppress halide volatility during calcination of the solution while further suppressing chloride volatility is achieved by increasing the aluminum to fluoride mole ratio in the waste solution prior to adding the calcium nitrate.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eibling, R.
Savannah River National Laboratory (SRNL) was asked to prepare saltstone from samples of Tank 50H obtained by SRNL on April 5, 2011 (Tank 50H sampling occurred on April 4, 2011) during 2QCY11 to determine the non-hazardous nature of the grout and for additional vault classification analyses. The samples were cured and shipped to Babcock & Wilcox Technical Services Group-Radioisotope and Analytical Chemistry Laboratory (B&W TSG-RACL) to perform the Toxic Characteristic Leaching Procedure (TCLP) and subsequent extract analysis on saltstone samples for the analytes required for the quarterly analysis saltstone sample. In addition to the eight toxic metals - arsenic, barium,more » cadmium, chromium, mercury, lead, selenium and silver - analytes included the underlying hazardous constituents (UHC) antimony, beryllium, nickel, and thallium which could not be eliminated from analysis by process knowledge. Additional inorganic species determined by B&W TSG-RACL include aluminum, boron, chloride, cobalt, copper, fluoride, iron, lithium, manganese, molybdenum, nitrate/nitrite as Nitrogen, strontium, sulfate, uranium, and zinc and the following radionuclides: gross alpha, gross beta/gamma, 3H, 60Co, 90Sr, 99Tc, 106Ru, 106Rh, 125Sb, 137Cs, 137mBa, 154Eu, 238Pu, 239/240Pu, 241Pu, 241Am, 242Cm, and 243/244Cm. B&W TSG-RACL provided subsamples to GEL Laboratories, LLC for analysis for the VOCs benzene, toluene, and 1-butanol. GEL also determines phenol (total) and the following radionuclides: 147Pm, 226Ra and 228Ra. Preparation of the 2QCY11 saltstone samples for the quarterly analysis and for vault classification purposes and the subsequent TCLP analyses of these samples showed that: (1) The saltstone waste form disposed of in the Saltstone Disposal Facility in 2QCY11 was not characteristically hazardous for toxicity. (2) The concentrations of the eight RCRA metals and UHCs identified as possible in the saltstone waste form were present at levels below the UTS. (3) Most of the inorganic species measured in the leachate do not exceed the MCL, SMCL or TW limits. (4) The inorganic waste species that exceeded the MCL by more than a factor of 10 were nitrate, nitrite and the sum of nitrate and nitrite. (5) Analyses met all quality assurance specifications of US EPA SW-846. (6) The organic species (benzene, toluene, 1-butanol, phenol) were either not detected or were less than reportable for the vault classification samples. (7) The gross alpha and radium isotopes could not be determined to the MCL because of the elevated background which raised the detection limits. (8) Most of the beta/gamma activity was from 137Cs and its daughter 137mBa. (9) The concentration of 137Cs and 90Sr were present in the leachate at concentrations 1/40th and 1/8th respectively than in the 2003 vault classification samples. The saltstone waste form placed in the Saltstone Disposal Facility in 2QCY11 met the SCHWMR R.61-79.261.24(b) RCRA metals requirements for a nonhazardous waste form. The TCLP leachate concentrations for nitrate, nitrite and the sum of nitrate and nitrite were greater than 10x the MCLs in SCDHEC Regulations R.61-107.19, Part I A, which confirms the Saltstone Disposal Facility classification as a Class 3 Landfill. The saltstone waste form placed in the Saltstone Disposal Facility in 2QCY11 met the R.61-79.268.48(a) non wastewater treatment standards.« less
DOE Waste Treatability Group Guidance
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kirkpatrick, T.D.
1995-01-01
This guidance presents a method and definitions for aggregating U.S. Department of Energy (DOE) waste into streams and treatability groups based on characteristic parameters that influence waste management technology needs. Adaptable to all DOE waste types (i.e., radioactive waste, hazardous waste, mixed waste, sanitary waste), the guidance establishes categories and definitions that reflect variations within the radiological, matrix (e.g., bulk physical/chemical form), and regulated contaminant characteristics of DOE waste. Beginning at the waste container level, the guidance presents a logical approach to implementing the characteristic parameter categories as part of the basis for defining waste streams and as the solemore » basis for assigning streams to treatability groups. Implementation of this guidance at each DOE site will facilitate the development of technically defined, site-specific waste stream data sets to support waste management planning and reporting activities. Consistent implementation at all of the sites will enable aggregation of the site-specific waste stream data sets into comparable national data sets to support these activities at a DOE complex-wide level.« less
Baker, Nancy T.; Wilson, John T.; Moran, Michael J.
2008-01-01
The U.S. Geological Survey (USGS) was one of numerous governmental agencies, private organizations, and the academic community that provided data and interpretations for the U.S. Environmental Protection Agency?s (USEPA) 2007 Report on the Environment: Science Report. This report documents the sources of data and methods used to develop selected water?quality indicators for the 2007 edition of the report compiled by USEPA. Stream and ground?water?quality data collected nationally in a consistent manner as part of the USGS?s National Water?Quality Assessment Program (NAWQA) were provided for several water?quality indicators, including Nitrogen and Phosphorus in Streams in Agricultural Watersheds; Pesticides in Streams in Agricultural Watersheds; and Nitrate and Pesticides in Shallow Ground Water in Agricultural Watersheds. In addition, the USGS provided nitrate (nitrate plus nitrite) and phosphorus riverine load estimates calculated from water?quality and streamflow data collected as part of its National Stream Water Quality Accounting Network (NASQAN) and its Federal?State Cooperative Program for the Nitrogen and Phosphorus Discharge from Large Rivers indicator.
Paramashivam, Dharini; Dickinson, Nicholas M; Clough, Timothy J; Horswell, Jacqui; Robinson, Brett H
2017-05-01
Biosolids disposal to landfill or through incineration is wasteful of a resource that is rich in organic matter and plant nutrients. Land application can improve soil fertility and enhance crop production but may result in excessive nitrate N (NO-N) leaching and residual contamination from pathogens, heavy metals, and xenobiotics. This paper evaluates evidence that these concerns can be reduced significantly by blending biosolids with organic materials to reduce the environmental impact of biosolids application to soils. It appears feasible to combine organic waste streams for use as a resource to build or amend degraded soils. Sawdust and partially pyrolyzed biochars provide an opportunity to reduce the environmental impact of biosolids application, with studies showing reductions of NO-N leaching of 40 to 80%. However, other organic amendments including lignite coal waste may result in excessive NO-N leaching. Field trials combining biosolids and biochars for rehabilitation of degraded forest and ecological restoration are recommended. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
A bioreactor system for the nitrogen loop in a Controlled Ecological Life Support System
NASA Technical Reports Server (NTRS)
Saulmon, M. M.; Reardon, K. F.; Sadeh, W. Z.
1996-01-01
As space missions become longer in duration, the need to recycle waste into useful compounds rises dramatically. This problem can be addressed by the development of Controlled Ecological Life Support Systems (CELSS) (i.e., Engineered Closed/Controlled Eco-Systems (ECCES)), consisting of human and plant modules. One of the waste streams leaving the human module is urine. In addition to the reclamation of water from urine, recovery of the nitrogen is important because it is an essential nutrient for the plant module. A 3-step biological process for the recycling of nitrogenous waste (urea) is proposed. A packed-bed bioreactor system for this purpose was modeled, and the issues of reaction step segregation, reactor type and volume, support particle size, and pressure drop were addressed. Based on minimization of volume, a bioreactor system consisting of a plug flow immobilized urease reactor, a completely mixed flow immobilized cell reactor to convert ammonia to nitrite, and a plug flow immobilized cell reactor to produce nitrate from nitrite is recommended. It is apparent that this 3-step bioprocess meets the requirements for space applications.
Becker, Mark F.; Peter, Kathy D.; Masoner, Jason
2002-01-01
Samples collected and analyzed by the Oklahoma Department of Agriculture, Food, and Forestry from 1999 to 2001 determined that nitrate exceeded the U.S. Environmental Protection Agency maximum contaminant level for public drinking-water supplies of 10 milligrams per liter as nitrogen in 79 monitoring wells at 35 swine licensed-managed feeding operations (LMFO) in Oklahoma. The LMFOs are located in rural agricultural settings where long-term agriculture has potentially affected the ground-water quality in some areas. Land use prior to the construction of the LMFOs was assessed to evaluate the types of agricultural land use within a 500-meter radius of the sampled wells. Chemical and microbiological techniques were used to determine the possible sources of nitrate in water sampled from 10 wastewater lagoons and 79 wells. Samples were analyzed for dissolved major ions, dissolved trace elements, dissolved nutrients, nitrogen isotope ratios of nitrate and ammonia, wastewater organic compounds, and fecal coliform bacteria. Bacteria ribotyping analysis was done on selected samples to identify possible specific animal sources. A decision process was developed to identify the possible sources of nitrate. First, nitrogen isotope ratios were used to define sources as animal, mixed animal and fertilizer, or fertilizer. Second, wastewater organic compound detections, nitrogen-isotope ratios, fecal coliform bacteria detections, and ribotyping were used to refine the identification of possible sources as LFMO waste, fertilizer, or unidentified animal or mixtures of these sources. Additional evidence provided by ribotyping and wastewater organic compound data can, in some cases, specifically indicate the animal source. Detections of three or more wastewater organic compounds that are indicators of animal sources and detections of fecal coliform bacteria provided additional evidence of an animal source. LMFO waste was designated as a possible source of nitrate in water from 10 wells. The source of waste in water from five of those wells was determined through ribotyping, and the source of waste in water from the remaining five wells was determined by detections of three or more animal-waste compounds in the well samples. LMFO waste in the water from wells with unidentified animal source of nitrate does not indicate that LMFO waste was not the source, but indicated that multiple animal sources, including LMFO waste, may be the source of the nitrate.
Buried Streams and the Loss of Ecosystem Services in Urban Watersheds
Nitrogen (N) retention in streams is an important ecosystem service that may be affected by the widespread burial of streams in stormwater pipes in urban watersheds. We predicted that stream burial suppresses the capacity of streams to retain nitrate (NO3-) by eliminating primary...
Long Term Dynamic Stream Nitrate and Phosphate Changes Following Watershed Wildfires
NASA Technical Reports Server (NTRS)
Ambrosia, Vincent G.; Brass, James A.; Riggan, Philip J.; Ewing, Roy; Sebesta, Paul D.; Peterson, David L. (Technical Monitor)
1994-01-01
During and following the 1988 Yellowstone National Park wildfires, airborne remotely sensed data were collected in order to characterize various vegetative components, fire front movements and bum intensities. ER-2 derived Thematic Mapper Simulator (TMS) data were used in conjunction with water sampling and chemistry analysis to determine fire intensities in various watersheds and aquatic system condition changes. The airborne Daedalus multispectral TMS data allowed the characterization of various bum intensities in watersheds. Stream sampling was then conducted in those various burned watersheds to determine nitrate and phosphate concentration changes. Six stream watersheds were monitored for five years (1989-1993) during non-snow periods (May/June through September): Cache Creek (intensely burned), Blacktail Deer Creek (intensely burned), Snake River (moderately burned), Lamar River (mixed burning), Soda Butte Creek (lightly burned), and Amphitheatre Creek (unburned). One litre samples were collected from those streams with ISCO water samplers every 12 hours. The samples were removed every 14 days .(28 Samples), and water chemistry analysis was performed. Chemistry analysis indicated that nitrate and phosphate concentrations were elevated in moderately burned watersheds and significantly elevated in severely burned watersheds. The results during the five year study indicate that bum intensities regulate stream water nitrate and phosphate concentrations, and that remotely sensed data can be used effectively to predict watershed chemical changes which will affect aquatic conditions.
Method of dye removal for the textile industry
Stone, Mark L.
2000-01-01
The invention comprises a method of processing a waste stream containing dyes, such as a dye bath used in the textile industry. The invention comprises using an inorganic-based polymer, such as polyphosphazene, to separate dyes and/or other chemicals from the waste stream. Membranes comprising polyphosphazene have the chemical and thermal stability to survive the harsh, high temperature environment of dye waste streams, and have been shown to completely separate dyes from the waste stream. Several polyphosplhazene membranes having a variety of organic substituent have been shown effective in removing color from waste streams.
Nitrate removal in deep sediments of a nitrogen-rich river network: A test of a conceptual model
Stelzer, Robert S.; Bartsch, Lynn
2012-01-01
Many estimates of nitrogen removal in streams and watersheds do not include or account for nitrate removal in deep sediments, particularly in gaining streams. We developed and tested a conceptual model for nitrate removal in deep sediments in a nitrogen-rich river network. The model predicts that oxic, nitrate-rich groundwater will become depleted in nitrate as groundwater upwelling through sediments encounters a zone that contains buried particulate organic carbon, which promotes redox conditions favorable for nitrate removal. We tested the model at eight sites in upwelling reaches of lotic ecosystems in the Waupaca River Watershed that varied by three orders of magnitude in groundwater nitrate concentration. We measured denitrification potential in sediment core sections to 30 cm and developed vertical nitrate profiles to a depth of about 1 m with peepers and piezometer nests. Denitrification potential was higher, on average, in shallower core sections. However, core sections deeper than 5 cm accounted for 70%, on average, of the depth-integrated denitrification potential. Denitrification potential increased linearly with groundwater nitrate concentration up to 2 mg NO3-N/L but the relationship broke down at higher concentrations (> 5 mg NO3-N/L), a pattern that suggests nitrate saturation. At most sites groundwater nitrate declined from high concentrations at depth to much lower concentrations prior to discharge into the surface water. The profiles suggested that nitrate removal occurred at sediment depths between 20 and 40 cm. Dissolved oxygen concentrations were much higher in deep sediments than in pore water at 5 cm sediment depth at most locations. The substantial denitrification potential in deep sediments coupled with the declines in nitrate and dissolved oxygen concentrations in upwelling groundwater suggest that our conceptual model for nitrate removal in deep sediments is applicable to this river network. Our results suggest that nitrate removal rates can be high in deep sediments of upwelling stream reaches, which may have implications for efforts to understand and quantify nitrogen transport and removal at larger scales.
Functional magnetic microspheres
NASA Technical Reports Server (NTRS)
Rembaum, Alan (Inventor); Landel, Robert F. (Inventor); Yen, Shiao-Ping S. (Inventor)
1981-01-01
Functional magnetic particles are formed by dissolving a mucopolysaccharide such as chitosan in acidified aqueous solution containing a mixture of ferrous chloride and ferric chloride. As the pH of the solution is raised magnetite is formed in situ in the solution by raising the pH. The dissolved chitosan is a polyelectrolyte and forms micelles surrounding the granules at pH of 8-9. The chitosan precipitates on the granules to form microspheres containing the magnetic granules. On addition of the microspheres to waste aqueous streams containing dissolved ions, the hydroxyl and amine functionality of the chitosan forms chelates binding heavy metal cations such as lead, copper, and mercury and the chelates in turn bind anions such as nitrate, fluoride, phosphate and borate.
NASA Astrophysics Data System (ADS)
Moren, I.; Worman, A. L. E.; Riml, J.
2017-12-01
Previous studies have shown that hyporheic exchange processes can be of great importance for the transport, retention and mass removal of nutrients in streams. Specifically, the flow of surface water through the hyporheic zone enhances redox-sensitive reactions such as coupled nitrification-denitrification. This self-cleaning capacity of streams can be utilized in stream restoration projects aiming to improve water quality by reconstructing the geomorphology of the streams. To optimize the effect of restoration actions we need quantitative understanding of the linkage between stream geomorphology, hyporheic exchange processes and the desired water quality targets. Here we propose an analytical, spectral methodology to evaluate how different stream geomorphologies induce hyporheic exchange on a wide range of spatial and temporal scales. Measurements of streambed topographies and surface water profiles from agricultural streams were used to calculate the average hyporheic exchange velocity and residence times and the result was compared with in-stream tracer test. Furthermore, the hyporheic exchange induced by steps in the surface water profile was derived as a comparison of the theoretical capacity of the system. Based on differences in hyporheic exchange, the mass removal of nitrate could be derived for the different geomorphologies. The maximum nitrate mass removal was found to be related to a specific Damkhöler number, which reflects that the mass removal can be either reaction or transport controlled. Therefore, although hyporheic exchange induced by steps in the surface water profile was generally larger than the hyporheic exchange in the observed natural reaches, this would not necessarily lead a larger nitrate mass removal provided that the hyporheic residence times are not long enough to facilitate denitrification processes. The study illustrates the importance to investigate a stream thoroughly before any remediation actions are implemented, specifically to evaluate if the mass removal is reaction or transport controlled.
MINEBANK RUN PROJECT AS AN APPROACH FOR RESTORING DEGRADED URBAN WATERSHEDS AND RIPARIAN ECOSYSTEMS
Elevated nitrate levels in streams and groundwater pose human and ecological threats. Minebank Run, an urban stream in Baltimore MD, will be restored in 2004/2005 using various techniques including reshaping stream banks to reconnect stream channel to flood plain, stream bank r...
Krom, M D; Ben David, A; Ingall, E D; Benning, L G; Clerici, S; Bottrell, S; Davies, C; Potts, N J; Mortimer, R J G; van Rijn, J
2014-06-01
Simultaneous removal of nitrogen and phosphorus by microbial biofilters has been used in a variety of water treatment systems including treatment systems in aquaculture. In this study, phosphorus, nitrate and sulfate cycling in the anaerobic loop of a zero-discharge, recirculating mariculture system was investigated using detailed geochemical measurements in the sludge layer of the digestion basin. High concentrations of nitrate and sulfate, circulating in the overlying water (∼15 mM), were removed by microbial respiration in the sludge resulting in a sulfide accumulation of up to 3 mM. Modelling of the observed S and O isotopic ratios in the surface sludge suggested that, with time, major respiration processes shifted from heterotrophic nitrate and sulfate reduction to autotrophic nitrate reduction. The much higher inorganic P content of the sludge relative to the fish feces is attributed to conversion of organic P to authigenic apatite. This conclusion is supported by: (a) X-ray diffraction analyses, which pointed to an accumulation of a calcium phosphate mineral phase that was different from P phases found in the feces, (b) the calculation that the pore waters of the sludge were highly oversaturated with respect to hydroxyapatite (saturation index = 4.87) and (c) there was a decrease in phosphate (and in the Ca/Na molar ratio) in the pore waters simultaneous with an increase in ammonia showing there had to be an additional P removal process at the same time as the heterotrophic breakdown of organic matter. Copyright © 2014 Elsevier Ltd. All rights reserved.
Triska, F.J.; Pringle, C.M.; Zellweger, G.W.; Duff, J.H.; Avanzino, R.J.
1993-01-01
In Costa Rica, the Salto River is enriched by geothermal-based soluble reactive phosphorus (SRP), which raises the concentration up to 200 ??g/L whereas Pantano Creek, an unimpacted tributary, has an SRP concentration <10 ??g/L. Ammonium concentration in springs adjacent to the Salto and Pantano was typically greater than channel water (13 of 22 locations) whereas nitrate concentration was less (20 of 22 locations). Ground waters were typically high in ammonium relative to nitrate whereas channel waters were high in nitrate relative to ammonium. Sediment slurry studies indicated nitrification potential in two sediment types, firm clay (3.34 ??g N.cm-3.d-1) and uncompacted organic-rich sediment (1.76 ??g N.cm-3.d-1). Ammonium and nitrate amendments to each stream separately resulted in nitrate concentrations in excess of that expected after correlation for dilution using a conservative tracer. SRP concentration was not affected by DIN amendment to either stream. SRP concentration in the Pantano appeared to be regulated by abiotic sediment exchange reactions. DIN composition and concentration were regulated by a combination of biotic and abiotic processes. -from Authors
Brian A. Pellerin; John Franco Saraceno; James B. Shanley; Stephen D. Sebestyen; George R. Aiken; Wilfred M. Wollheim; Brian A. Bergamaschi
2012-01-01
Highly resolved time series data are useful to accurately identify the timing, rate, and magnitude of solute transport in streams during hydrologically dynamic periods such as snowmelt. We used in situ optical sensors for nitrate (NO3-) and chromophoric dissolved organic matter fluorescence (FDOM) to measure surface water...
Broshears, R.E.; Clark, G.M.; Jobson, H.E.
2001-01-01
Stream discharge and the transport of nitrate, atrazine, and metolachlor in the Mississippi River Basin were simulated using the DAFLOW/BLTM hydrologic model. The simulated domain for stream discharge included river reaches downstream from the following stations in the National Stream Quality Accounting Network: Mississippi River at Clinton, IA; Missouri River at Hermann, MO: Ohio River at Grand Chain, IL: And Arkansas River at Little Rock, AR. Coefficients of hydraulic geometry were calibrated using data from water year 1996; the model was validated by favourable simulation of observed discharges in water years 1992-1994. The transport of nitrate, atrazine, and metolachlor was simulated downstream from the Mississippi River at Thebes, IL, and the Ohio River at Grand Chain. Simulated concentrations compared favourably with observed concentrations at Baton Rouge, LA. Development of this model is a preliminary step in gaining a more quantitative understanding of the sources and fate of nutrients and pesticides delivered from the Mississippi River Basin to the Gulf of Mexico.
Caffeine and pharmaceuticals as indicators of waste water contamination in wells
Seiler, R.L.; Zaugg, S.D.; Thomas, J.M.; Howcroft, D.L.
1999-01-01
The presence of caffeine or human pharmaceuticals in ground water with elevated nitrate concentrations can provide a clear, unambiguous indication that domestic waste water is a source of some of the nitrate. Water from domestic, public supply, and monitoring wells in three communities near Reno, Nevada, was sampled to test if caffeine or pharmaceuticals are common, persistent, and mobile enough in the environment that they can be detected in nitrate-contaminated ground water and, thus, can be useful indicators of recharge from domestic waste water. Results of this study indicate that these compounds can be used as indicators of recharge from domestic waste water, although their usefulness is limited because caffeine is apparently nonconservative and the presence of prescription pharmaceuticals is unpredictable. The absence of caffeine or pharmaceuticals in ground water with elevated nitrate concentrations does not demonstrate that the aquifer is free of waste water contamination. Caffeine was detected in ground water samples at concentrations up to 0.23 ??g/L. The human pharmaceuticals chlorpropamide, phensuximide, and carbamazepine also were detected in some samples.
NASA Astrophysics Data System (ADS)
Tesoriero, A. J.; Terziotti, S.
2014-12-01
Nitrate trends in streams often do not match expectations based on recent nitrogen source loadings to the land surface. Groundwater discharge with long travel times has been suggested as the likely cause for these observations. The fate of nitrate in groundwater depends to a large extent on the occurrence of denitrification along flow paths. Because denitrification in groundwater is inhibited when dissolved oxygen (DO) concentrations are high, defining the oxic-suboxic interface has been critical in determining pathways for nitrate transport in groundwater and to streams at the local scale. Predicting redox conditions on a regional scale is complicated by the spatial variability of reaction rates. In this study, logistic regression and boosted classification tree analysis were used to predict the probability of oxic water in groundwater in the Chesapeake Bay watershed. The probability of oxic water (DO > 2 mg/L) was predicted by relating DO concentrations in over 3,000 groundwater samples to indicators of residence time and/or electron donor availability. Variables that describe position in the flow system (e.g., depth to top of the open interval), soil drainage and surficial geology were the most important predictors of oxic water. Logistic regression and boosted classification tree analysis correctly predicted the presence or absence of oxic conditions in over 75 % of the samples in both training and validation data sets. Predictions of the percentages of oxic wells in deciles of risk were very accurate (r2>0.9) in both the training and validation data sets. Depth to the bottom of the oxic layer was predicted and is being used to estimate the effect that groundwater denitrification has on stream nitrate concentrations and the time lag between the application of nitrogen at the land surface and its effect on streams.
Griffiths, Natalie A.; Jackson, C. Rhett; McDonnell, Jeffrey J.; ...
2016-02-08
Nitrogen (N) is an important nutrient as it often limits productivity but in excess can impair water quality. Most studies on watershed N cycling have occurred in upland forested catchments where snowmelt dominates N export; fewer studies have focused on low-relief watersheds that lack snow. We examined watershed N cycling in three adjacent, low-relief watersheds in the Upper Coastal Plain of the southeastern United States to better understand the role of hydrological flow paths and biological transformations of N at the watershed scale. Groundwater was the dominant source of nitrified N to stream water in two of the three watersheds,more » while atmospheric deposition comprised 28% of stream water nitrate in one watershed. The greater atmospheric contribution may have been due to the larger stream channel area relative to total watershed area or the dominance of shallow subsurface flow paths contributing to stream flow in this watershed. There was a positive relationship between temperature and stream water ammonium concentrations and a negative relationship between temperature and stream water nitrate concentrations in each watershed suggesting that N cycling processes (i.e., nitrification and denitrification) varied seasonally. However, there were no clear patterns in the importance of denitrification in different water pools possibly because a variety of factors (i.e., assimilatory uptake, dissimilatory uptake, and mixing) affected nitrate concentrations. In conclusion, together, these results highlight the hydrological and biological controls on N cycling in low-gradient watersheds and variability in N delivery flow paths among adjacent watersheds with similar physical characteristics.« less
Pesticide and nitrate transport in an agriculturally influenced stream in Indiana.
Elias, Daniel; Bernot, Melody J
2017-04-01
Agrochemicals can be transported from agricultural fields into streams where they might have adverse effects on water quality and ecosystems. Three enrichment experiments were conducted in a central Indiana stream to quantify pesticide and nitrogen transport dynamics. In an enrichment experiment, a compound solution is added at a constant rate into a stream to increase compound background concentration. A conservative tracer (e.g., bromide) is added to determine discharge. Water and sediment samples are taken at several locations downstream to measure uptake metrics. We assessed transport of nitrate, atrazine, metolachlor, and carbaryl through direct measurement of uptake length (S w ), uptake velocity (V f ), and areal uptake (U). S w measures the distance traveled by a nutrient along the stream reach. V f measures the velocity a nutrient moves from the water column to immobilization sites. U represents the amount of nutrient immobilized in an area of streambed per unit of time. S w varied less than one order of magnitude across pesticides. The highest S w for atrazine suggests greater transport to downstream ecosystems. Across compounds, pesticide S w was longest in August relative to October and July. V f varied less than one order of magnitude across pesticides with the highest V f for metolachlor. U varied three orders of magnitude across pesticides with the highest U associate with sediment-bound carbaryl. Increasing nitrate S w suggests a lower nitrate demand of biota in this stream. Overall, pesticide transport was best predicted by compound solubility which can complement and improve models of pesticide abundance used by water quality programs and risk assessments.
NASA Astrophysics Data System (ADS)
Lockhart, K.; Harter, T.; Grote, M.; Young, M. B.; Eppich, G.; Deinhart, A.; Wimpenny, J.; Yin, Q. Z.
2014-12-01
Groundwater quality is a concern in alluvial aquifers underlying agricultural areas worldwide, an example of which is the San Joaquin Valley, California. Nitrate from land applied fertilizers or from animal waste can leach to groundwater and contaminate drinking water resources. Dairy manure and synthetic fertilizers are the major sources of nitrate in groundwater in the San Joaquin Valley, however, septic waste can be a major source in some areas. As in other such regions around the world, the rural population in the San Joaquin Valley relies almost exclusively on shallow domestic wells (≤150 m deep), of which many have been affected by nitrate. Consumption of water containing nitrate above the drinking water limit has been linked to major health effects including low blood oxygen in infants and certain cancers. Knowledge of the proportion of each of the three main nitrate sources (manure, synthetic fertilizer, and septic waste) contributing to individual well nitrate can aid future regulatory decisions. Nitrogen, oxygen, and boron isotopes can be used as tracers to differentiate between the three main nitrate sources. Mixing models quantify the proportional contributions of sources to a mixture by using the concentration of conservative tracers within each source as a source signature. Deterministic mixing models are common, but do not allow for variability in the tracer source concentration or overlap of tracer concentrations between sources. Bayesian statistics used in conjunction with mixing models can incorporate variability in the source signature. We developed a Bayesian mixing model on a pilot network of 32 private domestic wells in the San Joaquin Valley for which nitrate as well as nitrogen, oxygen, and boron isotopes were measured. Probability distributions for nitrogen, oxygen, and boron isotope source signatures for manure, fertilizer, and septic waste were compiled from the literature and from a previous groundwater monitoring project on several dairies in the San Joaquin Valley. Median percent contribution of nitrate to wells from fertilizer, manure, and septic waste generally match the expected source based on land use patterns, with some exceptions.
Logistic model of nitrate in streams of the upper-midwestern United States
Mueller, D.K.; Ruddy, B.C.; Battaglin, W.A.
1997-01-01
Nitrate in surface water can have adverse effects on aquatic life and, in drinking-water supplies, can be a risk to human health. As part of a regional study, nitrates as N (NO3-N) was analyzed in water samples collected from streams throughout 10 Midwestern states during synoptic surveys in 1989, 1990, and 1994. Data from the period immediately following crop planting at 124 sites were analyzed during logistic regression to relate discrete categories of NO3-N concentrations to characteristics of the basins upstream from the sites. The NO3-N data were divided into three categories representing probable background concentrations (10 mg L-1). Nitrate-N concentrations were positively correlated to streamflow, upstream area planted in corn (Zea mays L.), and upstream N- fertilizers application rates. Elevated NO3-N concentrations were associated with poorly drained soils and were weakly correlated with population density. Nitrate-N and streamflow data collected during 1989 and 1990 were used to calibrate the model, and data collected during 1994 were used for verification. The model correctly estimated NO3-N concentration categories for 79% of the samples in the calibration data set and 60% of the samples in the verification data set. The model was used to indicate where NO3-N concentrations might be elevated or exceed the NO3-N MCL in streams throughout the study area. The potential for elevated NO3-N concentrations was predicted to be greatest for streams in Illinois, Indiana, Iowa, and western Ohio.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCabe, Daniel J.; Wilmarth, William R.; Nash, Charles A.
2013-08-29
The purpose of this Process Development Plan is to summarize the objectives and plans for the technology development activities for an alternative path for disposition of the recycle stream that will be generated in the Hanford Waste Treatment Plant Low Activity Waste (LAW) vitrification facility (LAW Recycle). This plan covers the first phase of the development activities. The baseline plan for disposition of this stream is to recycle it to the WTP Pretreatment Facility, where it will be concentrated by evaporation and returned to the LAW vitrification facility. Because this stream contains components that are volatile at melter temperatures andmore » are also problematic for the glass waste form, they accumulate in the Recycle stream, exacerbating their impact on the number of LAW glass containers. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and reducing the halides in the Recycle is a key component of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, this stream does not have a proven disposition path, and resolving this gap becomes vitally important. This task seeks to examine the impact of potential future disposition of this stream in the Hanford tank farms, and to develop a process that will remove radionuclides from this stream and allow its diversion to another disposition path, greatly decreasing the LAW vitrification mission duration and quantity of glass waste. The origin of this LAW Recycle stream will be from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW melter off-gas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover or precipitates of scrubbed components (e.g. carbonates). The soluble components are mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet, and will not be available until the WTP begins operation, causing uncertainty in its composition, particularly the radionuclide content. This plan will provide an estimate of the likely composition and the basis for it, assess likely treatment technologies, identify potential disposition paths, establish target treatment limits, and recommend the testing needed to show feasibility. Two primary disposition options are proposed for investigation, one is concentration for storage in the tank farms, and the other is treatment prior to disposition in the Effluent Treatment Facility. One of the radionuclides that is volatile and expected to be in high concentration in this LAW Recycle stream is Technetium-99 ({sup 99}Tc), a long-lived radionuclide with a half-life of 210,000 years. Technetium will not be removed from the aqueous waste in the Hanford Waste Treatment and Immobilization Plant (WTP), and will primarily end up immobilized in the LAW glass, which will be disposed in the Integrated Disposal Facility (IDF). Because {sup 99}Tc has a very long half-life and is highly mobile, it is the largest dose contributor to the Performance Assessment (PA) of the IDF. Other radionuclides that are also expected to be in appreciable concentration in the LAW Recycle are {sup 129}I, {sup 90}Sr, {sup 137}Cs, and {sup 241}Am. The concentrations of these radionuclides in this stream will be much lower than in the LAW, but they will still be higher than limits for some of the other disposition pathways currently available. Although the baseline process will recycle this stream to the Pretreatment Facility, if the LAW facility begins operation first, this stream will not have a disposition path internal to WTP. One potential solution is to return the stream to the tank farms where it can be evaporated in the 242-A evaporator, or perhaps deploy an auxiliary evaporator to concentrate it prior to return to the tank farms. In either case, testing is needed to evaluate if this stream is compatible with the evaporator and the other wastes in the tank farm. It should be noted that prior experience in evaporation of another melter off-gas stream, the Recycle Stream at the SRS Defense Waste Processing Facility, unexpectedly caused deleterious impacts on evaporator scaling and formation of aluminosilicate solids before controls were implemented. The compatibility of this stream with other wastes and components in the tank farms has not been fully investigated, whether it is sent for storage in AW-102 in preparation for evaporation in 242-A evaporator, or if it is pre-concentrated in an auxiliary evaporator. This stream is expected to be unusual because it will be very high in corrosive species that are volatile in the melter (chloride, fluoride, sulfur), will have high ammonia, and will contain carryover particulates of glass-former chemicals. These species have potential to cause corrosion, precipitation, flammable gases, and scale in the tank farm system. Testing is needed to demonstrate acceptable conditions and limits for these compounds in wastes sent to the tank farms. Alternate disposition of this LAW Recycle stream could beneficially impact WTP, and may also remove a sizeable fraction of the 99Tc from the source term at the IDF. The alternative radionuclide removal process envisioned for this stream parallels the Actinide Removal Process that has been successfully used at SRS for several years. In that process, Monosodium Titanate (MST) is added to the tank waste to adsorb 90Sr and actinides, and then the MST and radionuclides are removed by filtration. The process proposed for investigation for the Hanford WTP LAW Recycle stream would similarly add MST to remove 90Sr and actinides, along with other absorbents or precipitating agents for the remaining radionuclides. These include inorganic reducing agents for Tc, and zeolites for 137Cs. After treatment, disposition of the decontaminated Recycle stream may be suitable for the Effluent Treatment Facility, where it could be evaporated and solidified. The contaminated slurry stream containing the absorbents and radionuclides will be preliminarily characterized in this phase of the program to evaluate disposal options, and disposition routes will be tested in the next phase. The testing described herein will aid in selection of the best disposal pathway. Several research tasks have been identified that are needed for this initial phase: imulant formulation- Concentration of Recycle to reduce storage volume; Blending of concentrated Recycle with tank waste; Sorption of radionuclides; Precipitation of radionuclides. After this initial phase of testing, additional tasks are expected to be identified for development. These tasks likely include evaluation and testing of applicable solid-liquid separation technologies, slurry rheology measurements, composition variability testing and evaluations, corrosion and erosion testing, slurry storage and immobilization investigations, and decontaminated Recycle evaporation and solidification. Although there are a number of unknown parameters listed in the technical details of the concepts described here, many of these parameters have precedence and do not generally require fundamental new scientific breakthroughs. Many of the materials and processes described are already used in radioactive applications in the DOE complex, or have been tested previously in comparable conditions. Some of these materials and equipment are already used in High Level Waste applications, which are much more complex and aggressive conditions than the LAW Recycle stream. In some cases, the unknown parameters are simply extensions of already studied conditions, such as tank waste corrosion chemistry. The list of testing needs at first appears daunting, but virtually all have been done before, although there are potential issues with compatibility with this unique waste stream. It is anticipated that the challenge will be more in integrating the system and complying with process limitations than in developing entirely new technologies. Several assumptions have been made in this document about the acceptability of radionuclide decontamination and potential waste forms for disposal. These assumptions have been used to define acceptability criteria for feasibility studies on removal. These limits are not intended to define regulatory or facility limits, but rather provide a starting point for evaluating various technologies.« less
Geomorphic stream restoration as an approach for reducing nutrients in degraded urban watersheds
Elevated nitrate levels in streams and groundwater pose human and ecological threats. Stream restoration may improve the nutrient removal capacity of streams, yet few studies have investigated the effectiveness of restoration as a nutrient BMP despite significant national effort...
Tsui, L.; Krapac, I.G.; Roy, W.R.
2007-01-01
Nitrate is a major agricultural pollutant found in drainage waters. Immature yard-waste compost was selected as a filter media to study its feasibility for removing nitrate from drainage water. Different operation parameters were tested to examine the denitrification efficiency, including the amounts of compost packed in columns, the flow rate, and the compost storage periods. The experimental results suggested that hydraulic retention time was the major factor to determine the extent of nitrate removal, although the amount of compost packed could also contribute to the nitrate removal efficiency. The effluent nitrate concentration increased as the flow rate decreased, and the compost column reduced nitrate concentrations from 20 mg/L to less than 5 mg/L within 1.5 h. The solution pH increased at the onset of experiment because of denitrification, but stabilized at a pH of about 7.8, suggesting that the compost had a buffering capacity to maintain a suitable pH for denitrification. Storing compost under air-dried conditions may diminish the extent nitrate removed initially, but the effects were not apparent after longer applications. It appeared that immature yard-waste compost may be a suitable material to remove nitrate from tile drainage water because of its relatively large organic carbon content, high microbial activity, and buffering capacity. ?? 2006 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gregory, Louis B.
This special analysis evaluates whether the Sandia National Laboratory (SNL) Classified Macroencapsulated Mixed Waste stream (ASLA000001007, Revision 4) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The SNL Classified Macroencapsulated Mixed Waste stream consists of debris from classified nuclear weapons components (SNL 2015). The SNL Classified Macroencapsulated Mixed Waste stream required a special analysis due to tritium (3H) exceeding the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015). The SNL Classifiedmore » Macroencapsulated Mixed Waste stream had no significant effect on the maximum mean and 95th percentile results for the resident air pathway and all-pathways annual total effective dose (TED). The SNL Classified Macroencapsulated Mixed Waste stream increases the mean air pathway and all-pathways annual TED from approximately 100 to 200 years after closure. Addition of the SNL Classified Macroencapsulated Mixed Waste stream inventory shifts the maximum TED to approximately 100 years after closure and increases the TED for several alternative exposure scenarios. The maximum mean and the 95th percentile 222Rn flux density remain less than the performance objective throughout the compliance period. The SNL Classified Macroencapsulated Mixed Waste stream is suitable for disposal by SLB at the Area 5 RWMS. The waste stream is recommended for approval without conditions.« less
Urbanization causes stream degradation in various ways, but perhaps the most extreme example is the burial of streams in underground storm drains to facilitate above ground development or to promote the rapid conveyance of stormwater. Stream burial is extensive in urban basins (...
Stream-aquifer interactions in the Straight River area, Becker and Hubbard counties, Minnesota
Stark, J.R.; Armstrong, David S.; Zwilling, Daniel R.
1994-01-01
Daily fluctuations of stream temperature are as great as 15 degrees Celsius during the summer, primarily in response to changes in air temperature. Ground-water discharge to the Straight River decreases stream temperature during the summer. Results of simulations from a stream-temperature model indicate that daily changes in stream temperature are strongly influenced by solar radiation, wind speed, stream depth, and ground-water inflow. Results of simulations from ground-water-flow and stream-temperature models developed for the investigation indicate a significant decrease in ground-water flow could result from ground-water withdrawal at rates similar to those measured during 1988. This reduction in discharge to the stream could result in an increase in stream temperature of 0.5 to 1.5 degrees Celsius. Nitrate concentrations in shallow wells screened at the water table, in some areas, are locally greater than the limit set by the Minnesota Pollution Control Agency. Nitrate concentrations in water from deeper wells and in the stream are low, generally less than 1.0 milligram per liter.
F. Worrall; Wayne T. Swank; T. P. Burt
2003-01-01
This study uses time series analysis to examine long-term stream water nitrate concentration records from a pair of forested catchments at the Coweeta Hydrologic Laboratory, North Carolina, USA. Monthly average concentrations were available from 1970 through 1997 for two forested catchments, one of which was clear-felled in 1977 and the other maintained as a control....
NASA Astrophysics Data System (ADS)
Sebestyen, S. D.; Campbell, J. L.; Shanley, J. B.; Pourmokhtarian, A.; Driscoll, C. T.; Boyer, E. W.
2009-12-01
There is a need to understand how climate variability and change affect nutrient delivery to surface waters. We analyzed long-term records of hydrochemical data to explore how the forms, concentrations, and loadings of nitrogen in forest streams throughout the northern USA vary with catchment wetness. We considered projected changes in growing season length and precipitation patterns to simulate future climate scenarios and to assess how stream nitrate loading responds to hydrological forcing under different climate change scenarios. At the Sleepers River Research Watershed in northeastern Vermont, model results suggest that stream nutrient loadings over the next century will respond to hydrological forcing during climate change that affects the amount of water that flows through the landscape. For example, growing season stream water yield (+20%) and nitrate loadings (+57%) increase in response to greater amounts of precipitation (+28%) during a warmer climate with a longer growing season (+43 days). We further explore these findings by presenting model results from a biogeochemical process model (PnET-BGC) to separate changes that are due to biogeochemical cycling and the effects of hydrological forcing. Our findings suggest that nitrogen cycling and transport will intensify during anthropogenic climate forcing, thereby affecting the timing and magnitude of annual stream nutrient loadings in northern forests of the USA.
Steele, G.V.; Cannia, J.C.; Sibray, S.S.; McGuire, V.L.
2005-01-01
Ground water is the source of drinking water for the residents of Pumpkin Creek Valley, western Nebraska. In this largely agricultural area, shallow aquifers potentially are susceptible to nitrate contamination. During the last 10 years, ground-water levels in the North Platte Natural Resources District have declined and contamination has become a major problem for the district. In 2000, the U.S. Geological Survey and the North Platte Natural Resources District began a cooperative study to determine the age and quality of the ground water and the sources of nitrogen in the aquifers in Pumpkin Creek Valley. Water samples were collected from 8 surface-water sites, 2 springs, and 88 ground-water sites during May, July, and August 2000. These samples were analyzed for physical properties, nutrients or nitrate, and hydrogen and oxygen isotopes. In addition, a subset of samples was analyzed for any combination of chlorofluorocarbons, tritium, tritium/helium, sulfur-hexafluoride, carbon-14, and nitrogen-15. The apparent age of ground water in the alluvial aquifer typically varied from about 1980 to modern, whereas ground water in the fractured Brule Formation had a median value in the 1970s. The Brule Formation typically contained ground water that ranged from the 1940s to the 1990s, but low-yield wells had apparent ages of 5,000 to 10,000 years before present. Data for oxygen-18 and deuterium indicated that lake-water samples showed the greatest effects from evaporation. Ground-water data showed no substantial evaporative effects and some ground water became isotopically heavier as the water moved downgradient. In addition, the physical and chemical ground-water data indicate that Pumpkin Creek is a gaining stream because little, if any, of its water is lost to the ground-water system. The water-quality type changed from a sodium calcium bicarbonate type near Pumpkin Creek's headwaters to a calcium sodium bicarbonate type near its mouth. Nitrate concentrations were largest in the alluvial system (median = 5 mg/L) and smallest in the surface-water system (median = 1 mg/L). Most nitrate concentrations exceeding the U.S. Environmental Protection Agency maximum contaminant level for drinking water of 10 mg/L as nitrogen were adjacent to irrigated fields and in areas where alluvial sediments are less than 50 ft thick. Sources of nitrogen in the ground water of the study area included naturally occurring nitrogen, commercial fertilizer, and animal waste. Based on nitrate concentration and delta nitrogen-15, the nitrogen in 65 percent of the water samples appears to have originated from a mixture of commercial fertilizers and animal waste. Some of the smallest nitrate concentrations in the ground-water samples contained some of the largest delta nitrogen-15 values (greater than 10 per mil), which suggests animal waste as the likely source. Commercial fertilizers were the likely source of most of the nitrogen in water samples with nitrate concentrations that exceeded 10 mg/L. The source of the nitrogen in water samples with nitrate concentrations exceeding 10 mg/L, but with delta nitrogen-15 values close to 10 per mil, could not be determined.
Majer, V.; Kram, P.; Shanley, J.B.
2005-01-01
Hydrochemical changes between 1991 and 2001 were assessed based on two synoptic stream surveys from the 820-km2 region of the Slavkov Forest and surrounding area, western Czech Republic. Marked declines of sulfate, nitrate, chloride, calcium and magnesium in surface waters were compared with other areas of Europe and North America recovering from acidification. Declines of sulfate concentration in the Slavkov Forest (-30 ??eq L-1 yr-1) were more dramatic than declines reported from other sites. However, these dramatic declines of strong acid anions did not generate a widespread increase of stream water pH in the Slavkov Forest. Only the most acidic streams experienced a slight increase of pH by 0.5 unit. An unexpected decline of stream water pH occurred in slightly alkaline streams. ?? 2004 Elsevier Ltd. All rights reserved.
Current and potential uses of bioactive molecules from marine processing waste.
Suleria, Hafiz Ansar Rasul; Masci, Paul; Gobe, Glenda; Osborne, Simone
2016-03-15
Food industries produce huge amounts of processing waste that are often disposed of incurring expenses and impacting upon the environment. For these and other reasons, food processing waste streams, in particular marine processing waste streams, are gaining popularity amongst pharmaceutical, cosmetic and nutraceutical industries as sources of bioactive molecules. In the last 30 years, there has been a gradual increase in processed marine products with a concomitant increase in waste streams that include viscera, heads, skins, fins, bones, trimmings and shellfish waste. In 2010, these waste streams equated to approximately 24 million tonnes of mostly unused resources. Marine processing waste streams not only represent an abundant resource, they are also enriched with structurally diverse molecules that possess a broad panel of bioactivities including anti-oxidant, anti-coagulant, anti-thrombotic, anti-cancer and immune-stimulatory activities. Retrieval and characterisation of bioactive molecules from marine processing waste also contributes valuable information to the vast field of marine natural product discovery. This review summarises the current use of bioactive molecules from marine processing waste in different products and industries. Moreover, this review summarises new research into processing waste streams and the potential for adoption by industries in the creation of new products containing marine processing waste bioactives. © 2015 Society of Chemical Industry.
Treatment Study Plan for Nitrate Salt Waste Remediation Revision 1.0
DOE Office of Scientific and Technical Information (OSTI.GOV)
Juarez, Catherine L.; Funk, David John; Vigil-Holterman, Luciana R.
2016-03-07
The two stabilization treatment methods that are to be examined for their effectiveness in the treatment of both the unremediated and remediated nitrate salt wastes include (1) the addition of zeolite and (2) cementation. Zeolite addition is proposed based on the results of several studies and analyses that specifically examined the effectiveness of this process for deactivating nitrate salts. Cementation is also being assessed because of its prevalence as an immobilization method used for similar wastes at numerous facilities around the DOE complex, including at Los Alamos. The results of this Treatment Study Plan will be used to provide themore » basis for a Resource Conservation and Recovery Act (RCRA) permit modification request of the LANL Hazardous Waste Facility Permit for approval by the New Mexico Environment Department-Hazardous Waste Bureau (NMED-HWB) of the proposed treatment process and the associated facilities.« less
NASA Astrophysics Data System (ADS)
Edgemon, G. L.; Danielson, M. J.; Bell, G. E. C.
1997-06-01
Underground waste tanks fabricated from mild steel store more than 253 million liters of high level radioactive waste from 50 years of weapons production at the Hanford Site. The probable modes of corrosion failures are reported as nitrate stress corrosion cracking and pitting. In an effort to develop a waste tank corrosion monitoring system, laboratory tests were conducted to characterize electrochemical noise data for both uniform and localized corrosion of mild steel and other materials in simulated waste environments. The simulated waste solutions were primarily composed of ammonium nitrate or sodium nitrate and were held at approximately 97°C. The electrochemical noise of freely corroding specimens was monitored, recorded and analyzed for periods ranging between 10 and 500 h. At the end of each test period, the specimens were examined to correlate electrochemical noise data with corrosion damage. Data characteristic of uniform corrosion and stress corrosion cracking are presented.
Drivers of atmospheric nitrate processing and export in forested catchments
Lucy A. Rose; Stephen D. Sebestyen; Emily M. Elliott; Keisuke Koba
2015-01-01
Increased deposition of reactive atmospheric N has resulted in the nitrogen saturation of many forested catchments worldwide. Isotope-based studies from multiple forest sites report low proportions (mean = ~10%) of unprocessed atmospheric nitrate in streams during baseflow, regardless of N deposition or nitrate export rates. Given similar proportions of...
NASA Astrophysics Data System (ADS)
Pasten-Zapata, Ernesto; Ledesma-Ruiz, Rogelio; Ramirez, Aldo; Harter, Thomas; Mahlknecht, Jürgen
2014-05-01
To effectively manage groundwater quality it is essential to understand sources of contamination and underground processes. The objective of the study was to identify sources and fate of nitrate pollution occurring in an aquifer underneath a sub-humid to humid region in NE Mexico which provides 10% of national citrus production. Nitrate isotopes and halide ratios were applied to understand nitrate sources and transformations in relation to land use/land cover. It was found that the study area is subject to diverse nitrate sources including organic waste and wastewater, synthetic fertilizers and soil processes. Animal manure and sewage from septic tanks were the causes of groundwater nitrate pollution within orchards and vegetable agriculture. Dairy activities within a radius of 1,000m from a sampling point increased nitrate pollution. Leachates from septic tanks incited nitrate pollution in residential areas. Soil nitrogen and animal waste were the sources of nitrate in groundwater under shrubland and grassland. Partial denitrification processes were evidenced. The denitrification process helped to attenuate nitrate concentration in the agricultural lands and grassland particularly during summer months.
River-groundwater connectivity and nutrient dynamics in a mesoscale catchment
NASA Astrophysics Data System (ADS)
Fleckenstein, Jan H.; Musolff, Andreas; Gilfedder, Benjamin; Frei, Sven; Wankmüller, Fabian; Trauth, Nico
2017-04-01
Diffuse solute exports from catchments are governed by many interrelated factors such as land use, climate, geological-/ hydrogeological setup and morphology. Those factors create spatial variations in solute concentrations and turnover rates in the subsurface as well as in the stream network. River-groundwater connectivity is a crucial control in this context: On the one hand groundwater is a main pathway for nitrate inputs to the stream. On the other hand, groundwater connectivity with the stream affects the magnitude of hyporheic exchange of stream water with the stream bed. We present results of a longitudinal sampling campaign along the Selke river, a 67 km long third-order stream in the Harz mountains in central Germany. Water quality at the catchment outlet is strongly impacted by agriculture with high concentrations of nitrate and a chemostatic nitrate export regime. However, the specific nitrate pathways to the stream are not fully understood as there is arable land distributed throughout the catchment. While the sparsely distributed arable land in the mountainous upper catchment receives much higher amounts of precipitation, the downstream alluvial plains are drier, but more intensively used. The three-day campaign was conducted in June 2016 under constant low flow conditions. Stream water samples were taken every 2 km along the main stem of the river and at its major tributaries. Samples were analyzed for field parameters, major cations and anions, N-O isotopes, nutrients and Radon-222 (Rn) concentrations. Additionally, at each sampling location, river discharge was manually measured using current meters. Groundwater influxes to each sampled river section were quantified from the Rn measurements using the code FINIFLUX, (Frei and Gilfedder 2015). Rn and ion concentrations showed an increase from the spring to the mouth, indicating a growing impact of groundwater flux to the river. However, increases in groundwater gains were not gradual. The strongest gains were observed downstream of where the Selke River leaves the Harz Mountains and enters the alluvial plains. At this location, land use, hydrogeological setup and river slope as well as average slope of the contributing catchment area change significantly. Downstream of this point 15N isotope values were also significantly higher, suggesting higher denitrification activity in the deeper aquifers of lower catchment. While specific discharge (discharge per catchment area) was 3 times higher in the upper catchment, nitrate mass flux per area was more than 3 times higher in lower catchment compared to the respective other part of the catchment. We conclude that catchment morphology, (hydro)geology and hydrology control river-groundwater connectivity while the interplay with land use controls in stream nitrate concentrations. Repeated sampling campaigns will allow assessing seasonal changes in solute inputs and turnover. References Frei, S. & Gilfedder, B.S. (2015): FINIFLUX: An implicit finite element model for quantification of groundwater fluxes and hyporheic exchange in streams and rivers using radon. Water Resources Research, DOI: 10.1002/2015WR017212.
Nitrogen (N) retention in stream networks is an important ecosystem service that may be affected by the widespread burial of headwater streams in urban watersheds. Stream burial occurs when segments of a channel are encased in drainage pipe and buried beneath the land surface to...
Waste streams in a crewed space habitat
NASA Technical Reports Server (NTRS)
Wydeven, T.; Golub, M. A.
1991-01-01
A judicious compilation of generation rates and chemical compositions of potential waste feed streams in a typical crewed space habitat was made in connection with the waste-management aspect of NASA's Physical/Chemical Closed-Loop Life Support Program. Waste composition definitions are needed for the design of waste-processing technologies involved in closing major life support functions in future long-duration human space missions. Tables of data for the constituents and chemical formulas of the following waste streams are presented and discussed: human urine, feces, hygiene (laundry and shower) water, cleansing agents, trash, humidity condensate, dried sweat, and trace contaminants. Tables of data on dust generation and pH values of the different waste streams are also presented and discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lambertin, D.; Chartier, D.; Joussot-Dubien, C.
2007-07-01
Since the late sixties, bitumen has been widely used by the nuclear industry as a matrix for the immobilization of low- and intermediate level radioactive waste originating mainly from the nuclear activities: precipitation or evaporator concentrates, ion exchange resins, incinerator ashes, and filter materials. Depending on bitumen and operating conditions, bituminization of radioactive waste can be operated between 130 and 180 deg. C, so chemical reaction can be induced with nitrate or nitrite towards elements contained in waste (TPB, potassium nickel ferrocyanide and cobalt compound) and bitumen. These reactions are mainly exothermic this is the reason why the enthalpy reactionmore » and their temperature of initiation have to be determined independently of their concentration in waste. In this work, we have studied by Calvet Calorimetry at 0.1 deg. C/min heating rates, the behaviour of chemical elements especially oxido-reduction couples that can react at a temperature range 100- 300 deg. C (Nitrate/PPFeNi, Nitrite/PPFeNi, Nitrate/TBP, Nitrite/TBP, Nitrate/bitumen and Nitrite/bitumen). The initial temperature reaction of nitrates or nitrites towards potassium nickel ferrocyanide (PPFeNi) has been studied and is equal respectively to 225 deg. C and 175 deg. C. Because of the large scale temperature reaction of nitrate and PPFeNi, enthalpy reaction can not be calculated, although enthalpy reaction of nitrite and PPFeNi is equal to 270 kJ/mol of nitrite. Sodium Nitrate and TBP behaviour has been investigated, and an exothermic reaction at 135 deg. C until 250 deg. C is evidenced. The exothermic energy reaction is a function of TBP concentration and the enthalpy reaction has been determined. (authors)« less
40 CFR 63.1096 - What requirements must I comply with if I transfer waste off-site?
Code of Federal Regulations, 2010 CFR
2010-07-01
... or transport of each waste stream. The notice shall state that the waste stream contains organic HAP... written certification that the transferee will manage and treat any waste stream received from a source... providing this written certification to the Administrator, the certifying entity accepts responsibility for...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shott, Gregory J.
This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) EnergyX Macroencapsulated waste stream (B LAMACRONCAP, Revision 1) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL EnergyX Macroencapsulated waste stream is macroencapsulated mixed waste generated during research laboratory operations and maintenance (LLNL 2015). The LLNL EnergyX Macroencapsulated waste stream required a special analysis due to tritium (3H), cobalt-60 (60Co), cesium-137 (137Cs), and radium-226 (226Ra) exceeding the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclearmore » Security Administration Nevada Field Office [NNSA/NFO] 2015).The results indicate that all performance objectives can be met with disposal of the waste stream in a SLB trench. Addition of the LLNL EnergyX Macroencapsulated inventory slightly increases multiple performance assessment results, with the largest relative increase occurring for the all-pathways annual total effective dose (TED). The maximum mean and 95th percentile 222Rn flux density remain less than the performance objective throughout the compliance period. The LLNL EnergyX Macroencapsulated waste stream is suitable for disposal by SLB at the Area 5 RWMS. The waste stream is recommended for approval without conditions.« less
Verifiable metamodels for nitrate losses to drains and groundwater in the Corn Belt, USA
Nolan, Bernard T.; Malone, Robert W.; Gronberg, Jo Ann M.; Thorp, K.R.; Ma, Liwang
2012-01-01
Nitrate leaching in the unsaturated zone poses a risk to groundwater, whereas nitrate in tile drainage is conveyed directly to streams. We developed metamodels (MMs) consisting of artificial neural networks to simplify and upscale mechanistic fate and transport models for prediction of nitrate losses by drains and leaching in the Corn Belt, USA. The two final MMs predicted nitrate concentration and flux, respectively, in the shallow subsurface. Because each MM considered both tile drainage and leaching, they represent an integrated approach to vulnerability assessment. The MMs used readily available data comprising farm fertilizer nitrogen (N), weather data, and soil properties as inputs; therefore, they were well suited for regional extrapolation. The MMs effectively related the outputs of the underlying mechanistic model (Root Zone Water Quality Model) to the inputs (R2 = 0.986 for the nitrate concentration MM). Predicted nitrate concentration was compared with measured nitrate in 38 samples of recently recharged groundwater, yielding a Pearson’s r of 0.466 (p = 0.003). Predicted nitrate generally was higher than that measured in groundwater, possibly as a result of the time-lag for modern recharge to reach well screens, denitrification in groundwater, or interception of recharge by tile drains. In a qualitative comparison, predicted nitrate concentration also compared favorably with results from a previous regression model that predicted total N in streams.
Biological denitrification of high concentration nitrate waste
Francis, Chester W.; Brinkley, Frank S.
1977-01-01
Biological denitrification of nitrate solutions at concentrations of greater than one kilogram nitrate per cubic meter is accomplished anaerobically in an upflow column having as a packing material a support for denitrifying bacteria.
Nitrate in ground water and spring water near four dairy farms in North Florida, 1990-93
Andrews, W.J.
1994-01-01
Concentrations of nitrate and other selected water- quality characteristics were analyzed periodically for two years in water from 51 monitoring wells installed at four farms and in water discharging from three nearby springs along the Suwannee River in Lafayette and Suwannee Counties to examine the quality of ground water at these farms and the transport of nutrients in ground water to the nearby spring-fed Suwannee River: Ground water from shallow wells, which were completed in the top ten feet of the saturated zone in a surficial sandy aquifer and in the karstic Upper Floridan aquifer generally had the highest concentrations of nitrate, ranging from <.02 to 130 mg/L as nitrogen. Nitrate concentrations commonly exceeded the primary drinking water standard of 10 mg/L for nitrate as nitrogen in water from shallow wells, which tapped the top ten feet of the uppermost aquifers near waste-disposal areas such as wastewater lagoons and defoliated, intensive-use areas near milking barns. Upgradient from waste-disposal areas, concentrations of nitrate in ground water were commonly less than 1 mg/L as nitrogen. Water samples from deep wells (screened 20 feet deeper than shallow wells in these aquifers) generally had lower concentrations of nitrate (ranging from <0.02 to 84 mg/L) than water from shallow wells. Water samples from the three monitored springs (Blue, Telford, and Convict Springs) had nitrate concentrations ranging from 1.5 to 6.5 mg/L as nitrogen, which were higher than those typically occurring in water from upgradient wells at the monitored dairy farms or from back- ground wells sampled in the region. Analyses of nitrogen isotope ratios in nitrate indicated that leachate from animal wastes was the principal source of nitrate in ground water adjacent to waste-disposal areas at the monitored and unmonitored dairy farms. Leachate from a combi- nation of fertilizers, soils, and animal wastes appeared to be the source of nitrate in ground- water downgradient from pastures and wastewater spray fields at dairy farms and in water discharging from three nearby springs. Although denitrifying bacteria were present in counts sometimes exceeding 240,000 colonies/100mL in water from dairy-farm monitoring wells, ground water in the uppermost aquifers in Lafayette and Suwannee Counties generally contained too much oxygen for denitrification to remove nitrate from shallow ground water. Denitrification was more likely to occur in deeper ground water, which typically has lower dissolved oxygen concentrations.
Application of classification-tree methods to identify nitrate sources in ground water
Spruill, T.B.; Showers, W.J.; Howe, S.S.
2002-01-01
A study was conducted to determine if nitrate sources in ground water (fertilizer on crops, fertilizer on golf courses, irrigation spray from hog (Sus scrofa) wastes, and leachate from poultry litter and septic systems) could be classified with 80% or greater success. Two statistical classification-tree models were devised from 48 water samples containing nitrate from five source categories. Model I was constructed by evaluating 32 variables and selecting four primary predictor variables (??15N, nitrate to ammonia ratio, sodium to potassium ratio, and zinc) to identify nitrate sources. A ??15N value of nitrate plus potassium 18.2 indicated inorganic or soil organic N. A nitrate to ammonia ratio 575 indicated nitrate from golf courses. A sodium to potassium ratio 3.2 indicated spray or poultry wastes. A value for zinc 2.8 indicated poultry wastes. Model 2 was devised by using all variables except ??15N. This model also included four variables (sodium plus potassium, nitrate to ammonia ratio, calcium to magnesium ratio, and sodium to potassium ratio) to distinguish categories. Both models were able to distinguish all five source categories with better than 80% overall success and with 71 to 100% success in individual categories using the learning samples. Seventeen water samples that were not used in model development were tested using Model 2 for three categories, and all were correctly classified. Classification-tree models show great potential in identifying sources of contamination and variables important in the source-identification process.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martinez, Patrick Thomas; Chamberlin, Rebecca M.; Schwartz, Daniel S.
2015-09-16
Solid debris was recovered from the previously-emptied nitrate salt waste drum S855793. The bulk sample was nondestructively assayed for radionuclides in its as-received condition. Three monoliths were selected for further characterization. Two of the monoliths, designated Specimen 1 and 3, consisted primarily of sodium nitrate and lead nitrate, with smaller amounts of lead nitrate oxalate and lead oxide by powder x-ray diffraction. The third monolith, Specimen 2, had a complex composition; lead carbonate was identified as the predominant component, and smaller amounts of nitrate, nitrite and carbonate salts of lead, magnesium and sodium were also identified. Microfocused x-ray fluorescence (MXRF)more » mapping showed that lead was ubiquitous throughout the cross-sections of Specimens 1 and 2, while heteroelements such as potassium, calcium, chromium, iron, and nickel were found in localized deposits. MXRF examination and destructive analysis of fragments of Specimen 3 showed elevated concentrations of iron, which were broadly distributed through the sample. With the exception of its high iron content and low carbon content, the chemical composition of Specimen 3 was within the ranges of values previously observed in four other nitrate salt samples recovered from emptied waste drums.« less
NASA Astrophysics Data System (ADS)
Broshears, Robert E.; Clark, Gregory M.; Jobson, Harvey E.
2001-05-01
Stream discharge and the transport of nitrate, atrazine, and metolachlor in the Mississippi River Basin were simulated using the DAFLOW/BLTM hydrologic model. The simulated domain for stream discharge included river reaches downstream from the following stations in the National Stream Quality Accounting Network: Mississippi River at Clinton, IA; Missouri River at Hermann, MO; Ohio River at Grand Chain, IL; and Arkansas River at Little Rock, AR. Coefficients of hydraulic geometry were calibrated using data from water year 1996; the model was validated by favourable simulation of observed discharges in water years 1992-1994. The transport of nitrate, atrazine, and metolachlor was simulated downstream from the Mississippi River at Thebes, IL, and the Ohio River at Grand Chain. Simulated concentrations compared favourably with observed concentrations at Baton Rouge, LA. Development of this model is a preliminary step in gaining a more quantitative understanding of the sources and fate of nutrients and pesticides delivered from the Mississippi River Basin to the Gulf of Mexico. Published in 2001 by John Wiley & Sons, Ltd.
Apparatus and method for two-stage oxidation of wastes
Fleischman, Scott D.
1995-01-01
An apparatus and method for oxidizing wastes in a two-stage process. The apparatus includes an oxidation device, a gas-liquid contacting column and an electrocell. In the first stage of the process, wastes are heated in the presence of air to partially oxidize the wastes. The heated wastes produce an off-gas stream containing oxidizable materials. In the second stage, the off-gas stream is cooled and flowed through the contacting column, where the off-gas stream is contacted with an aqueous acid stream containing an oxidizing agent having at least two positive valence states. At least a portion of the oxidizable materials are transferred to the acid stream and destroyed by the oxidizing agent. During oxidation, the valence of the oxidizing agent is decreased from its higher state to its lower state. The acid stream is flowed to the electrocell, where an electric current is applied to the stream to restore the oxidizing agent to its higher valence state. The regenerated acid stream is recycled to the contacting column.
Krantz, David E.; Powars, David S.
2000-01-01
The types and distribution of Coastal Plain sediments in the Patuxent River Basin may contribute to relatively low concentrations of nitrate (typically less than 1 milligram per liter) in stream base flow because of the chemical reduction of dissolved nitrate (denitrification) in ground water. Water chemistry data from synoptic stream base-flow surveys in the Patuxent River Basin show higher dissolved nitrate concentrations in the Piedmont than in the Coastal Plain section of the watershed. Stream base flow reflects closely the chemistry of ground water discharging from the surficial (unconfined) aquifer to the stream. Because land use in the sampled subbasins is virtually the same in each section, differences in the physical and geochemical characteristics of the surficial aquifer may explain the observed differences in water chemistry. One possible cause of lower nitrate concentrations in the Coastal Plain is denitrification within marine sediments that contain chemically reduced compounds. During denitrification, the oxygen atoms on the nitrate (N03-) molecule are transferred to a reduced compound and N gas is produced. Organic carbon and ferrous iron (Fe2+), derived from the dissolution of minerals such as pyrite (FeS2) and glauconite (an iron aluminosilicate clay), can act as reducing substrates; these reduced chemical species are common in the marine and estuarine deposits in Southern Maryland. The spatial distribution of geologic units and their lithology (sediment type) has been used to create a map of the potential for denitrification of ground water in the surficial aquifer of the Coastal Plain in Southern Maryland.
An Evaluation of Nitrate, fDOM, and Turbidity Sensors in New Hampshire Streams
NASA Astrophysics Data System (ADS)
Snyder, Lisle; Potter, Jody D.; McDowell, William H.
2018-03-01
A state-of-the-art network of water quality sensors was established in 2012 to gather year-round high temporal frequency hydrochemical data in streams and rivers throughout the state of New Hampshire. This spatially extensive network includes eight headwater stream and two main stem river monitoring sites, spanning a variety of stream orders and land uses. Here we evaluate the performance of nitrate, fluorescent dissolved organic matter (fDOM), and turbidity sensors included in the sensor network. Nitrate sensors were first evaluated in the laboratory for interference by different forms of dissolved organic carbon (DOC), and then for accuracy in the field across a range of hydrochemical conditions. Turbidity sensors were assessed for their effectiveness as a proxy for concentrations of total suspended solids (TSS) and total particulate C and N, and fDOM as a proxy for concentrations of dissolved organic matter. Overall sensor platform performance was also examined by estimating percentage of data loss due to sensor failures or related malfunctions. Although laboratory sensor trials show that DOC can affect optical nitrate measurements, our validations with grab samples showed that the optical nitrate sensors provide a reliable measurement of NO3 concentrations across a wide range of conditions. Results showed that fDOM is a good proxy for DOC concentration (r2 = 0.82) but is a less effective proxy for dissolved organic nitrogen (r2 = 0.41). Turbidity measurements from sensors correlated well with TSS (r2 = 0.78), PC (r2 = 0.53), and PN (r2 = 0.51).
Harden, Stephen L.; Spruill, Timothy B.
2008-01-01
An analysis of data collected at five flow-path study sites between 1997 and 2006 was performed to identify the factors needed to formulate a comprehensive program, with a focus on nitrogen, for protecting ground water and surface water in the North Carolina Coastal Plain. Water-quality protection in the Coastal Plain requires the identification of factors that affect the transport of nutrients from recharge areas to streams through the shallow ground-water system. Some basins process or retain nitrogen more readily than others, and the factors that affect nitrogen processing and retention were the focus of this investigation to improve nutrient management in Coastal Plain streams and to reduce nutrient loads to coastal waters. Nitrate reduction in ground water was observed at all five flow-path study sites in the North Carolina Coastal Plain, although the extent of reduction at each site was influenced by various environmental, hydrogeologic, and geochemical factors. Denitrification was the most common factor responsible for decreases in nitrate along the ground-water flow paths. Specific factors, some of which affect denitrification rates, that appeared to influence ground-water nitrate concentrations along the flow paths or in the streams include soil drainage, presence or absence of riparian buffers, evapotranspiration, fertilizer use, ground-water recharge rates and residence times, aquifer properties, subsurface tile drainage, sources and amounts of organic matter, and hyporheic processes. The study data indicate that the nitrate-reducing capacity of the buffer zone combined with that of the hyporheic zone can substantially lower the amount of ground-water nitrate discharged to streams in agricultural settings of the North Carolina Coastal Plain. At the watershed scale, the effects of ground-water discharge on surface-water quality appear to be greatly influenced by streamflow conditions and the presence of extensive riparian vegetation. Streamflow statistics that reflect base flow and the general hydrologic dynamics of a stream are important in understanding nutrient transport from a watershed and may be useful indicators of watersheds that are likely to have higher yields of nutrients and water. Combining streamflow statistics with information on such factors as land use, soil drainage, extent of riparian vegetation, geochemical conditions, and subsurface tile drainage in the Coastal Plain can be useful in identifying watersheds that are most likely to export excessive nitrogen due to nonpoint-source loadings and watersheds that are effective in processing nitrogen.
Evaluating Chemical Tracers as Indicators of Nitrate-Nitrogen Sources in Groundwater
NASA Astrophysics Data System (ADS)
Nitka, A.; DeVita, W.; McGinley, P.
2014-12-01
Groundwater nitrate-N concentrations greater than 3 mg/L usually indicate contamination from either agriculture or wastewater disposal. The objective of this study was to use chemical indicators to reliably determine sources of nitrate contamination in private wells. We developed an analytical method for a suite of human waste indicators. The selection of chemical tracers was based on their likely occurrence and mobility in groundwater. The suite included artificial sweeteners, pharmaceuticals and personal care products. Pesticide metabolites were used to identify contamination due to agricultural practices. A densely populated suburban area with adjacent agricultural land was selected. Eighteen private water supply wells and six monitoring wells were analyzed for nitrate-N and contaminant indicators. All of the wells with nitrate concentrations greater than 3 mg/L had at least one chemical indicator. Of these, 90% had two or more human waste contaminants, 40% had pesticide metabolites, and 30% had both. Of the wells with nitrate greater than 10 mg/L, 80% had two or more human waste indicators, 70% had pesticide metabolites, and 50% had both. The results of this research will help direct land management decisions and selection of appropriate water treatment options.
NASA Astrophysics Data System (ADS)
Price, A.; Wollheim, W. M.; Mulukutla, G. K.; Carey, R. O.; McDowell, W. H.
2012-12-01
Understanding the aquatic biogeochemical impacts of land use change and climate variability will require improved understanding of nutrient variability over temporal scales ranging from storms to seasons. New in situ sensor technology offers the prospect of efficient nutrient measurements over multiple time scales. We quantified nutrient flux patterns in response to storm events across seasons using in situ nutrient sensors deployed in headwater streams draining three land use types (forest, suburban, and agriculture) within the Lamprey River watershed, New Hampshire, between April-December 2012. We utilized two sensor suites, each consisting of a Satlantic Submersible Ultraviolet Nitrate Analyzer (NO3-N), Turner Designs C6 Multi-Sensor Platform (CDOM, Turbidity, Chl), Hydrolab MS5 (Dissolved Oxygen, pH), WET Labs Cycle P (PO4-P), and Hobo Water Level & Conductivity meters. Preliminary spring/summer comparisons at the suburban site suggest increased baseflow nitrate concentrations and decreased diurnal nitrate variability (~0.05 vs. 0.035 mg/L daily fluctuation) following leaf emergence in spring. Nitrate concentrations were diluted during storms. Hysteresis was evident, suggesting groundwater nitrate sources attributable to septic systems were diluted by surface runoff during spring storms. The agricultural stream showed similar but more extreme patterns of increasing baseflow nitrate during the summer (~2.4 to 4.1 mg/L) and dilution during storms. The compilation of a high-frequency dataset for headwater streams across seasons and land-use types will provide valuable insight into complex land use/water quality relationships in urbanizing watersheds.
Leachate pre-treatment strategies before recirculation in landfill bioreactors.
Vigneron, V; Bouchez, T; Bureau, C; Mailly, N; Mazeas, L; Duquennoi, C; Audic, J M; Hébé, L; Bernet, N
2005-01-01
Nitrified leachate recirculation represents a promising strategy for a more sustainable landfill management. Our objective was to determine the reactions involved in nitrate reduction in municipal solid waste batch biodegradation tests. Anaerobic digestion of waste in the three control reactors showed a good reproducibility. In two test reactors, nitrate was added at various moments of the waste degradation process. We observed that: (1) H2S concentration controlled the nitrate reduction pathway: above a certain threshold of H2S, dissimilatory nitrate reduction to ammonium (DNRA) replaced denitrification. (2) N2O/N2 ratio varied with the organic carbon concentration: the lower the easily biodegradable carbon concentration, the higher the N2O/N2 ratio. (3) N2 was consumed after denitrification. The possibility of a nitrogen fixation reaction in the presence of NH4 is discussed. Nitrified leachate recirculation during acidogenesis should be avoided because of higher H2S production which could induce DNRA.
Bio-electrochemical removal of nitrate from water and wastewater--a review.
Ghafari, Shahin; Hasan, Masitah; Aroua, Mohamed Kheireddine
2008-07-01
Nitrates in different water and wastewater streams raised concerns due to severe impacts on human and animal health. Diverse methods are reported to remove nitrate from water streams which almost fail to entirely treat nitrate, except biological denitrification which is capable of reducing inorganic nitrate compounds to harmless nitrogen gas. Review of numerous studies in biological denitrification of nitrate containing water resources, aquaculture wastewaters and industrial wastewater confirmed the potential of this method and its flexibility towards the remediation of different concentrations of nitrate. The denitrifiers could be fed with organic and inorganic substrates which have different performances and subsequent advantages or disadvantages. Review of heterotrophic and autotrophic denitrifications with different food and energy sources concluded that autotrophic denitrifiers are more effective in denitrification. Autotrophs utilize carbon dioxide and hydrogen as the source of carbon substrate and electron donors, respectively. The application of this method in bio-electro reactors (BERs) has many advantages and is promising. However, this method is not so well established and documented. BERs provide proper environment for simultaneous hydrogen production on cathodes and appropriate consumption by immobilized autotrophs on these cathodes. This survey covers various designs and aspects of BERs and their performances.
Generation rates and chemical compositions of waste streams in a typical crewed space habitat
NASA Technical Reports Server (NTRS)
Wydeven, Theodore; Golub, Morton A.
1990-01-01
A judicious compilation of generation rates and chemical compositions of potential waste feed streams in a typical crewed space habitat was made in connection with the waste-management aspect of NASA's Physical/Chemical Closed-Loop Life Support Program. Waste composition definitions are needed for the design of waste-processing technologies involved in closing major life support functions in future long-duration human space missions. Tables of data for the constituents and chemical formulas of the following waste streams are presented and discussed: human urine, feces, hygiene (laundry and shower) water, cleansing agents, trash, humidity condensate, dried sweat, and trace contaminants. Tables of data on dust generation and pH values of the different waste streams are also presented and discussed.
NASA Astrophysics Data System (ADS)
Griffiths, N. A.; Mulholland, P. J.; Jackson, C. R.; McDonnell, J. J.; Blake, J. I.; Du, E.; Klaus, J.; Langholtz, M.
2012-12-01
In the southeastern U.S., intensively-managed pine plantations are projected to be a significant source of feedstocks for bioenergy, and the environmental sustainability (water quality, quantity) of this practice needs to be addressed at the watershed scale. In the Upper Coastal Plain of South Carolina, we are examining water quality in 3 forested watersheds (1 reference [R], 2 treatment watersheds [B, C]) before and after the conversion to loblolly pine for bioenergy. We collected pre-treatment water quality data (nitrogen, phosphorus, dissolved organic carbon [DOC], herbicides) from all watersheds for two years (2009-2011) to determine baseline conditions. In May 2012, 40% of the extant forest in the two treatment watersheds was harvested and planting of loblolly pine will begin in early 2013. We will discuss our pre-treatment water quality results from the 3 study watersheds in context with our watershed-scale experiment. Baseline stream chemistry differed among the three watersheds, with higher mean concentrations of ammonium (59 μg/L) and DOC (8.1 mg/L) in Watershed R than in Watersheds B (ammonium = 17 μg/L, DOC = 6.9 μg/L) and C (ammonium = 17 μg/L, DOC = 6.1 μg/L), suggesting that anaerobic conditions in Watershed R may influence stream chemistry. Stream nitrate concentrations were higher in Watershed B (111 μg/L) than in Watersheds R (29 μg/L) and C (30 μg/L), suggesting that shallower flowpaths may be contributing to stream water chemistry. Dual isotope analysis of nitrate (15N, 18O) suggests that riparian groundwater is the source of nitrate in streams. However, nitrate in precipitation can be an important source to these watersheds during storms, as nitrate in flowing soil water had similar δ18O-NO3 values to precipitation. Nitrate may travel more conservatively in these watersheds than ammonium or phosphorus, as an irrigation experiment which simulated nutrient deposition from rainwater showed that the majority of added ammonium and phosphorus is removed (via uptake and/or sorption) compared to nitrate. Overall, quantifying baseline water chemistry among the three watersheds prior to the establishment of loblolly pine is necessary in order to determine any potential effects that short-rotation pine management may have on water quality.
Equilibrium Temperature Profiles within Fission Product Waste Forms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaminski, Michael D.
2016-10-01
We studied waste form strategies for advanced fuel cycle schemes. Several options were considered for three waste streams with the following fission products: cesium and strontium, transition metals, and lanthanides. These three waste streams may be combined or disposed separately. The decay of several isotopes will generate heat that must be accommodated by the waste form, and this heat will affect the waste loadings. To help make an informed decision on the best option, we present computational data on the equilibrium temperature of glass waste forms containing a combination of these three streams.
Coprocessed nuclear fuels containing (U, Pu) values as oxides, carbides or carbonitrides
Lloyd, M.H.
1981-01-09
Method for direct coprocessing of nuclear fuels derived from a product stream of fuels reprocessing facility containing uranium, plutonium, and fission product values comprising nitrate stabilization of said stream vacuum concentration to remove water and nitrates, neutralization to form an acid deficient feed solution for the internal gelation mode of sol-gel technology, green spherule formation, recovery and treatment for loading into a fuel element by vibra packed or pellet formation technologies.
Coprocessed nuclear fuels containing (U, Pu) values as oxides, carbides or carbonitrides
Lloyd, Milton H.
1983-01-01
Method for direct coprocessing of nuclear fuels derived from a product stream of a fuels reprocessing facility containing uranium, plutonium, and fission product values comprising nitrate stabilization of said stream vacuum concentration to remove water and nitrates, neutralization to form an acid deficient feed solution for the internal gelation mode of sol-gel technology, green spherule formation, recovery and treatment for loading into a fuel element by vibra packed or pellet formation technologies.
Nyhan, J W; White, G C; Trujillo, G
1982-10-01
Stream channel sediments and adjacent bank soils found in three intermittent streams used for treated liquid effluent disposal at Los Alamos, New Mexico were sampled to determine the distribution of 238Pu, 239,240Pu and 137Cs. Radionuclide concentrations and inventories were determined as functions of distance downstream from the waste outfall and from the center of the stream channel, soil sampling depth, stream channel-bank physiography, and the waste use history of each disposal area. Radionuclide concentrations in channel sediments were inversely related to distances up to 10 km downstream from the outfalls. For sites receiving appreciable waste effluent additions, contaminant concentrations in bank soils decreased with perpendicular distances greater than 0.38 m from the stream channel, and with stream bank sampling depths greater than 20-40 cm. Concentrations and total inventories of radionuclides in stream bank soils generally decreased as stream bank height increased. Inventory estimates of radionuclides in channel sediments exhibited coefficients of variation that ranged 0.41-2.6, reflecting the large variation in radionuclide concentrations at each site. Several interesting temporal relationships of these radionuclides in intermittent streams were gleaned from the varying waste use histories of the three effluent-receiving areas. Eleven yr after liquid wastes were added to one canyon, the major radionuclide inventories were found in the stream bank soils, unlike most of the other currently-used receiving areas. A period of time greater than 6 yr seems to be required before the plutonium in liquid wastes currently added to the canyon is approximately equilibrated with the plutonium in the bank soils. These observations are discussed relative to waste management practices in these southwestern intermittent streams.
STREAM CORRIDOR RESTORATION AND ITS POTENTIAL TO IMPROVE WATER QUALITY
Watershed stream corridors are being degraded by anthropogenic impacts of increased flow from runoff, sediment loading from erosion and contaminants such as nitrate from non-point sources. One solution is to restore stream corridors with bank stabilization and energy dissipation ...
Urban Stream Burial Increases Watershed-Scale Nitrate Export.
Beaulieu, Jake J; Golden, Heather E; Knightes, Christopher D; Mayer, Paul M; Kaushal, Sujay S; Pennino, Michael J; Arango, Clay P; Balz, David A; Elonen, Colleen M; Fritz, Ken M; Hill, Brian H
2015-01-01
Nitrogen (N) uptake in streams is an important ecosystem service that reduces nutrient loading to downstream ecosystems. Here we synthesize studies that investigated the effects of urban stream burial on N-uptake in two metropolitan areas and use simulation modeling to scale our measurements to the broader watershed scale. We report that nitrate travels on average 18 times farther downstream in buried than in open streams before being removed from the water column, indicating that burial substantially reduces N uptake in streams. Simulation modeling suggests that as burial expands throughout a river network, N uptake rates increase in the remaining open reaches which somewhat offsets reduced N uptake in buried reaches. This is particularly true at low levels of stream burial. At higher levels of stream burial, however, open reaches become rare and cumulative N uptake across all open reaches in the watershed rapidly declines. As a result, watershed-scale N export increases slowly at low levels of stream burial, after which increases in export become more pronounced. Stream burial in the lower, more urbanized portions of the watershed had a greater effect on N export than an equivalent amount of stream burial in the upper watershed. We suggest that stream daylighting (i.e., uncovering buried streams) can increase watershed-scale N retention.
Urban Stream Burial Increases Watershed-Scale Nitrate Export
Beaulieu, Jake J.; Golden, Heather E.; Knightes, Christopher D.; Mayer, Paul M.; Kaushal, Sujay S.; Pennino, Michael J.; Arango, Clay P.; Balz, David A.; Elonen, Colleen M.; Fritz, Ken M.; Hill, Brian H.
2015-01-01
Nitrogen (N) uptake in streams is an important ecosystem service that reduces nutrient loading to downstream ecosystems. Here we synthesize studies that investigated the effects of urban stream burial on N-uptake in two metropolitan areas and use simulation modeling to scale our measurements to the broader watershed scale. We report that nitrate travels on average 18 times farther downstream in buried than in open streams before being removed from the water column, indicating that burial substantially reduces N uptake in streams. Simulation modeling suggests that as burial expands throughout a river network, N uptake rates increase in the remaining open reaches which somewhat offsets reduced N uptake in buried reaches. This is particularly true at low levels of stream burial. At higher levels of stream burial, however, open reaches become rare and cumulative N uptake across all open reaches in the watershed rapidly declines. As a result, watershed-scale N export increases slowly at low levels of stream burial, after which increases in export become more pronounced. Stream burial in the lower, more urbanized portions of the watershed had a greater effect on N export than an equivalent amount of stream burial in the upper watershed. We suggest that stream daylighting (i.e., uncovering buried streams) can increase watershed-scale N retention. PMID:26186731
Transformation of nitrogen and distribution of nitrogen-related bacteria in a polluted urban stream.
Jiao, Y; Jin, W B; Zhao, Q L; Zhang, G D; Yan, Y; Wan, J
2009-01-01
Most researchers focused on either nitrogen species or microbial community for polluted urban stream while ignoring the interaction between them and its effect on nitrogen transformation, which restricted the rational selection of an effective and feasible remediation technology. Taking Buji stream in Shenzhen (China) as target stream, the distribution of nitrogen-related bacteria was investigated by most probable number (MPN) besides analysis of nitrogen species etc. The nitrogen-related bacteria in sediment were 10(2) times richer than those in water. Owing to their faster growth, the MPN of ammonifying bacteria and denitrifying bacteria were 10(5) and 10(2) times higher than those of nitrifying bacteria, respectively. The ammonifying bacteria numbers were significantly related to BOD5 in water, while nitrifying bacteria in sediment correlated well with nitrate in water. Thus, nitrification occurred mainly in sediment surface and was limited by low proportion of nitrifying bacteria. The denitrifying bacteria in sediment had good relationship with BOD5 and nitrite and nitrate in water. Low DO and rich organic compounds were beneficial to denitrification but unfavourable to nitrification. Denitrification was restricted by low nitrite and nitrate concentration. These results could be served as a reference for implementing the remediation scheme of nitrogen polluted urban stream.
Auditing an intensive care unit recycling program.
Kubicki, Mark A; McGain, Forbes; O'Shea, Catherine J; Bates, Samantha
2015-06-01
The provision of health care has significant direct environmental effects such as energy and water use and waste production, and indirect effects, including manufacturing and transport of drugs and equipment. Recycling of hospital waste is one strategy to reduce waste disposed of as landfill, preserve resources, reduce greenhouse gas emissions, and potentially remain fiscally responsible. We began an intensive care unit recycling program, because a significant proportion of ICU waste was known to be recyclable. To determine the weight and proportion of ICU waste recycled, the proportion of incorrect waste disposal (including infectious waste contamination), the opportunity for further recycling and the financial effects of the recycling program. We weighed all waste and recyclables from an 11-bed ICU in an Australian metropolitan hospital for 7 non-consecutive days. As part of routine care, ICU waste was separated into general, infectious and recycling streams. Recycling streams were paper and cardboard, three plastics streams (polypropylene, mixed plastics and polyvinylchloride [PVC]) and commingled waste (steel, aluminium and some plastics). ICU waste from the waste and recycling bins was sorted into those five recycling streams, general waste and infectious waste. After sorting, the waste was weighed and examined. Recycling was classified as achieved (actual), potential and total. Potential recycling was defined as being acceptable to hospital protocol and local recycling programs. Direct and indirect financial costs, excluding labour, were examined. During the 7-day period, the total ICU waste was 505 kg: general waste, 222 kg (44%); infectious waste, 138 kg (27%); potentially recyclable waste, 145 kg (28%). Of the potentially recyclable waste, 70 kg (49%) was actually recycled (14% of the total ICU waste). In the infectious waste bins, 82% was truly infectious. There was no infectious contamination of the recycling streams. The PVC waste was 37% contaminated (primarily by other plastics), but there was less than 1% contamination of other recycling streams. The estimated cost of the recycling program was about an additional $1000/year. In our 11-bed ICU, we recycled 14% of the total waste produced over 7-days, which was nearly half of the potentially recyclable waste. There was no infectious contamination of recyclables and minimal contamination with other waste streams, except for the PVC plastic. The estimated annual cost of the recycling program was $1000, reflecting the greater cost of disposal of some recyclables (paper and cardboard v most plastic types).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shott, Gregory J.
This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) Low Activity Beta/Gamma Sources waste stream (BCLALADOEOSRP, Revision 0) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL Low Activity Beta/Gamma Sources waste stream consists of sealed sources that are no longer needed. The LLNL Low Activity Beta/Gamma Sources waste stream required a special analysis because cobalt-60 (60Co), strontium-90 (90Sr), cesium-137 (137Cs), and radium-226 (226Ra) exceeded the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclearmore » Security Administration Nevada Field Office [NNSA/NFO] 2015). The results indicate that all performance objectives can be met with disposal of the LLNL Low Activity Beta/Gamma Sources in a SLB trench. The LLNL Low Activity Beta/Gamma Sources waste stream is suitable for disposal by SLB at the Area 5 RWMS. However, the activity concentration of 226Ra listed on the waste profile sheet significantly exceeds the action level. Approval of the waste profile sheet could potentially allow the disposal of high activity 226Ra sources. To ensure that the generator does not include large 226Ra sources in this waste stream without additional evaluation, a control is need on the maximum 226Ra inventory. A limit based on the generator’s estimate of the total 226Ra inventory is recommended. The waste stream is recommended for approval with the control that the total 226Ra inventory disposed shall not exceed 5.5E10 Bq (1.5 Ci).« less
NASA Astrophysics Data System (ADS)
Aalto, Sanni L.; Saarenheimo, Jatta; Karvinen, Anu; Rissanen, Antti J.; Ropponen, Janne; Juntunen, Janne; Tiirola, Marja
2016-04-01
European commission has obliged Baltic states to reduce nitrate load, which requires high investments on the nitrate removal processes and may increase emissions of greenhouse gases, e.g. N2O, in the waste water treatment plants. We used ecosystem-scale experimental approach to test a novel sediment filtration method for economical waste water N removal in Lake Keurusselkä, Finland between 2014 and 2015. By spatially optimizing the waste water discharge, the contact area and time of nitrified waste water with the reducing microbes of the sediment was increased. This was expected to enhance microbial-driven N transformation and to alter microbial community composition. We utilized 15N isotope pairing technique to follow changes in the actual and potential denitrification rates, nitrous oxide formation and dissimilatory nitrate reduction to ammonium (DNRA) in the lake sediments receiving nitrate-rich waste water input and in the control site. In addition, we investigated the connections between observed process rates and microbial community composition and functioning by using next generation sequencing and quantitative PCR. Furthermore, we estimated the effect of sediment filtration method on waste water contact time with sediment using the 3D hydrodynamic model. We sampled one year before the full-scale experiment and observed strong seasonal patterns in the process rates, which reflects the seasonal variation in the temperature-related mixing patterns of the waste water within the lake. During the experiment, we found that spatial optimization enhanced both actual and potential denitrification rates of the sediment. Furthermore, it did not significantly promote N2O emissions, or N retention through DNRA. Overall, our results indicate that sediment filtration can be utilized as a supplemental or even alternative method for the waste water N removal.
McCarty, Gregory W.; Hapeman, Cathleen J.; Rice, Clifford P.; Hively, W. Dean; McConnell, Laura L.; Sadeghi, Ali M.; Lang, Megan W.; Whitall, David R.; Bialek, Krystyna; Downey, Peter
2014-01-01
Over 50% of streams in the Chesapeake Bay watershed have been rated as poor or very poor based on the index of biological integrity. The Choptank River estuary, a Bay tributary on the eastern shore, is one such waterway, where corn and soybean production in upland areas of the watershed contribute significant loads of nutrients and sediment to streams. We adopted a novel approach utilizing the relationship between the concentration of nitrate-N and the stable, water-soluble herbicide degradation product MESA {2-[2-ethyl-N-(1-methoxypropan-2-yl)-6-methylanilino]-2-oxoethanesulfonic acid} to distinguish between dilution and denitrification effects on the stream concentration of nitrate-N in agricultural subwatersheds. The ratio of mean nitrate-N concentration/(mean MESA concentration * 1000) for 15 subwatersheds was examined as a function of percent cropland on hydric soil. This inverse relationship (R2 = 0.65, p 2 ≤ 0.99) for all eight sampling dates except one where R2 = 0.90. This very strong correlation indicates that nitrate-N was conserved in much of the Choptank River estuary, that dilution alone is responsible for the changes in nitrate-N and MESA concentrations, and more importantly nitrate-N loads are not reduced in the estuary prior to entering the Chesapeake Bay. Thus, a critical need exists to minimize nutrient export from agricultural production fields and to identify specific conservation practices to address the hydrologic conditions within each subwatershed. In well drained areas, removal of residual N within the cropland is most critical, and practices such as cover crops which sequester the residual N should be strongly encouraged. In poorly drained areas where denitrification can occur, wetland restoration and controlled drained structures that minimize ditch flow should be used to maximize denitrification.
Response of an algal assemblage to nutrient enrichment and shading in a Hawaiian stream
Stephens, S.H.; Brasher, A.M.D.; Smith, C.M.
2012-01-01
To investigate the effects of nitrate enrichment, phosphate enrichment, and light availability on benthic algae, nutrient-diffusing clay flowerpots were colonized with algae at two sites in a Hawaiian stream during spring and autumn 2002 using a randomized factorial design. The algal assemblage that developed under the experimental conditions was investigated by determining biomass (ash-free dry mass and chlorophyll a concentrations) and composition of the diatom assemblage. In situ pulse amplitude-modulated fluorometry was also used to model photosynthetic rate of the algal assemblage. Algal biomass and maximum photosynthetic rate were significantly higher at the unshaded site than at the shaded site. These parameters were higher at the unshaded site with either nitrate, or to a lesser degree, nitrate plus phosphate enrichment. Analysis of similarity of diatom assemblages showed significant differences between shaded and unshaded sites, as well as between spring and autumn experiments, but not between nutrient treatments. However, several individual species of diatoms responded significantly to nitrate enrichment. These results demonstrate that light availability (shaded vs. unshaded) is the primary limiting factor to algal growth in this stream, with nitrogen as a secondary limiting factor. ?? 2011 Springer Science+Business Media B.V.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yamada, W.I.; Faucette, A.M.; Jantzen, R.C.
1993-08-30
Mixed wastes at the Rocky Flats Plant (RFP) are subject to regulation by the Resource Conservation and Recovery Act (RCRA). Polymer solidification is being developed as a final treatment technology for several of these mixed wastes, including nitrate salts. Encapsulation nitrate salts with low density polyethylene (LDPE) has been the preliminary focus of the RFP polymer solidification effort. Literature reviews, industry surveys, and lab-scale and pilot-scale tests have been conducted to evaluate several options for encapsulating nitrate salts with LDPE. Most of the effort has focused on identifying compatible drying and extrusion technologies. Other processing options, specifically meltration and non-heatedmore » compounding machines, were also investigated. The best approach appears to be pretreatment of the nitrate salt waste brine in either a vertical or horizontal thin film evaporator followed by compounding of the dried waste with LDPE in an intermeshing, co-rotating, twin-screw extruder. Additional pilot-scale tests planned for the fall of 1993 should further support this recommendation. Preliminary evaluation work indicates that meltration is not possible at atmospheric pressure with the LDPE (Chevron PE-1409) provided by RFP. However, meltration should be possible at atmospheric pressure using another LDPE formulation with altered physical and rheological properties: Lower molecular weight and lower viscosity (Epoline C-15). Contract modifications are now in process to allow a follow-on pilot scale demonstration. Questions regarding changed safety and physical properties of the resultant LDPE waste form due to use of the Epoline C-15 will be addressed. No additional work with non-heated mixer compounder machines is planned at this time.« less
Ehrlich, G.G.; Godsy, E.M.; Pascale, C.A.; Vecchioli, John
1979-01-01
An industrial waste liquid containing organonitrile compounds and nitrate ion has been injected into the lower limestone of the Floridan aquifer near Pensacola, Florida since June 1975. Chemical analyses of water from monitor wells and backflow from the injection well indicate that organic carbon compounds are converted to CO2 and nitrate is converted to N2. These transformations are caused by bacteria immediately after injection, and are virtually completed within 100 m of the injection well. The zone near the injection well behaves like an anaerobic filter with nitrate respiring bacteria dominating the microbial flora in this zone.Sodium thiocyanate contained in the waste is unaltered during passage through the injection zone and is used to detect the degree of mixing of injected waste liquid with native water at a monitor well 312 m (712 ft) from the injection well. The dispersivity of the injection zone was calculated to be 10 m (33 ft). Analyses of samples from the monitor well indicate 80 percent reduction in chemical oxygen demand and virtually complete loss of organonitriles and nitrate from the waste liquid during passage from the injection well to the monitor well. Bacterial densities were much lower at the monitor well than in backflow from the injection well.
About the Managing and Transforming Waste Streams Tool
The Managing and Transforming Waste Streams Tool was developed by a team of zero waste consultants and solid waste program managers making informed observations from hands-on work in communities, with contributions from EPA.
Simultaneous Thermal Analysis of WIPP and LANL Waste Drum Samples: A Preliminary Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wayne, David M.
2015-10-19
On Friday, February 14, 2014, an incident in P7R7 of the WIPP underground repository released radioactive material into the environment. The direct cause of the event was a breached transuranic (TRU) waste container, subsequently identified as Drum 68660. Photographic and other evidence indicates that the breach of 68660 was caused by an exothermic event. Subsequent investigations (Britt, 2015; Clark and Funk, 2015; Wilson et al., 2015; Clark, 2015) indicate that the combination of nitrate salts, pH neutralizing chemicals, and organic-based adsorbent represented a potentially energetic mixture. The materials inside the breached steel drum consisted of remediated, 30- to 40-year old,more » Pu processing wastes from LANL. The contents were processed and repackaged in 2014. Processing activities at LANL included: 1) neutralization of acidic liquid contents, 2) sorption of the neutralized liquid, and 3) mixing of acidic nitrate salts with an absorber to meet waste acceptance criteria. The contents of 68660 and its sibling, 68685, were derived from the same parent drum, S855793. Drum S855793 originally contained ten plastic bags of acidic nitrate salts, and four bags of mixed nitrate and oxalate salts generated in 1985 by Pu recovery operations. These salts were predominantly oxalic acid, hydrated nitrate salts of Mg, Ca, and Fe, anhydrous Na(NO 3), and minor amounts of anhydrous and hydrous nitrate salts of Pb, Al, K, Cr, and Ni. Other major components include sorbed water, nitric acid, dissolved nitrates, an absorbent (Swheat Scoop®) and a neutralizer (KolorSafe®). The contents of 68660 are described in greater detail in Appendix E of Wilson et al. (2015)« less
2013-03-31
certainly remain comingled with other solid waste. For example, some bases provided containers for segregation of recyclables including plastic and...prevalent types of solid waste are food (19.1% by average sample weight), wood (18.9%), and plastics (16.0%) based on analysis of bases in...within the interval shown. Food and wood wastes are the largest components of the average waste stream (both at ~19% by weight), followed by plastic
Sequential pyrolysis of plastic to recover polystyrene HCL and terephthalic acid
Evans, Robert J.; Chum, Helena L.
1995-01-01
A process of pyrolyzing plastic waste feed streams containing polyvinyl chloride, polyethylene terephthalate, polystyrene and polyethylene to recover polystyrene HCl and terephthalic acid comprising: heating the plastic waste feed stream to a first temperature; adding an acid or base catalyst on an oxide or carbonate support; heating the plastic waste feed stream to pyrolyze polyethylene terephthalate and polyvinyl chloride; separating terephthalic acid or HCl; heating to a second temperature to pyrolyze polystyrene; separating styrene; heating the waste feed stream to a third temperature to pyrolyze polyethylene; and separating hydrocarbons.
Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Kärki, Janne
2014-11-01
In this work, the fraction of construction and demolition waste (C&D waste) complicated and economically not feasible to sort out for recycling purposes is used to produce solid recovered fuel (SRF) through mechanical treatment (MT). The paper presents the mass, energy and material balances of this SRF production process. All the process streams (input and output) produced in MT waste sorting plant to produce SRF from C&D waste are sampled and treated according to CEN standard methods for SRF. Proximate and ultimate analysis of these streams is performed and their composition is determined. Based on this analysis and composition of process streams their mass, energy and material balances are established for SRF production process. By mass balance means the overall mass flow of input waste material stream in the various output streams and material balances mean the mass flow of components of input waste material stream (such as paper and cardboard, wood, plastic (soft), plastic (hard), textile and rubber) in the various output streams of SRF production process. The results from mass balance of SRF production process showed that of the total input C&D waste material to MT waste sorting plant, 44% was recovered in the form of SRF, 5% as ferrous metal, 1% as non-ferrous metal, and 28% was sorted out as fine fraction, 18% as reject material and 4% as heavy fraction. The energy balance of this SRF production process showed that of the total input energy content of C&D waste material to MT waste sorting plant, 74% was recovered in the form of SRF, 16% belonged to the reject material and rest 10% belonged to the streams of fine fraction and heavy fraction. From the material balances of this process, mass fractions of plastic (soft), paper and cardboard, wood and plastic (hard) recovered in the SRF stream were 84%, 82%, 72% and 68% respectively of their input masses to MT plant. A high mass fraction of plastic (PVC) and rubber material was found in the reject material stream. Streams of heavy fraction and fine fraction mainly contained non-combustible material (such as stone/rock, sand particles and gypsum material). Copyright © 2014 Elsevier Ltd. All rights reserved.
Harris, S.H.; Smith, R.L.
2009-01-01
Nitrification and nitrate reduction were examined in an ephemeral drainage channel receiving discharge from coalbed natural gas (CBNG) production wells in the Powder River Basin, Wyoming. CBNG co-produced water typically contains dissolved inorganic nitrogen (DIN), primarily as ammonium. In this study, a substantial portion of discharged ammonium was oxidized within 50??m of downstream transport, but speciation was markedly influenced by diel fluctuations in dissolved oxygen (> 300????M). After 300??m of transport, 60% of the initial DIN load had been removed. The effect of benthic nitrogen-cycling processes on stream water chemistry was assessed at 2 locations within the stream channel using acrylic chambers to conduct short-term (2-6??h), in-stream incubations. The highest ambient DIN removal rates (2103????mol N m- 2 h- 1) were found at a location where ammonium concentrations > 350????M. This occurred during light incubations when oxygen concentrations were highest. Nitrification was occurring at the site, however, net accumulation of nitrate and nitrite accounted for < 12% of the ammonium consumed, indicating that other ammonium-consuming processes were also occurring. In dark incubations, nitrite and nitrate consumption were dominant processes, while ammonium was produced rather than consumed. At a downstream location nitrification was not a factor and changes in DIN removal rates were controlled by nitrate reduction, diel fluctuations in oxygen concentration, and availability of electron donor. This study indicates that short-term adaptation of stream channel processes can be effective for removing CBNG DIN loads given sufficient travel distances, but the long-term potential for nitrogen remobilization and nitrogen saturation remain to be determined.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kot, Wing K.; Pegg, Ian L.; Brandys, Marek
One of the primary roles of waste pretreatment at the Hanford Tank Waste Treatment and Immobilization Plant (WTP) is to separate the majority of the radioactive components from the majority of the nonradioactive components in retrieved tank wastes, producing a high level waste (HLW) stream and a low activity waste (LAW) stream. This separation process is a key element in the overall strategy to reduce the volume of HLW that requires vitrification and subsequent disposal in a national deep geological repository for high level nuclear waste. After removal of the radioactive constituents, the LAW stream, which has a much largermore » volume but smaller fraction of radioactivity than the HLW stream, will be immobilized and disposed of in near surface facilities at the Hanford site.« less
NASA Astrophysics Data System (ADS)
Hinsby, Klaus; Markager, Stiig; Kronvang, Brian; Windolf, Jørgen; Sonnenborg, Torben; Sørensen, Lærke
2015-04-01
Nitrate, which typically makes up the major part (~>90%) of dissolved inorganic nitrogen in groundwater and surface water, is the most frequent pollutant responsible for European groundwater bodies failing to meet the good status objectives of the European Water Framework Directive generally when comparing groundwater monitoring data with the nitrate quality standard of the Groundwater Directive (50 mg/l = the WHO drinking water standard). Still, while more than 50 % of the European surface water bodies do not meet the objective of good ecological status "only" 25 % of groundwater bodies do not meet the objective of good chemical status according to the river basin management plans reported by the EU member states. However, based on a study on interactions between groundwater, streams and a Danish estuary we argue that nitrate threshold values for aerobic groundwater often need to be significantly below the nitrate quality standard to ensure good ecological status of associated surface water bodies, and hence that the chemical status of European groundwater is worse than indicated by the present assessments. Here we suggest a methodology for derivation of groundwater and stream threshold values for total nitrogen ("nitrate") in a coastal catchment based on assessment of maximum acceptable nitrogen loadings (thresholds) to the associated vulnerable estuary. The applied method use existing information on agricultural practices and point source emissions in the catchment, groundwater, stream quantity and quality monitoring data that all feed data to an integrated groundwater and surface water modelling tool enabling us to conduct an assessment of total nitrogen loads and threshold concentrations derived to ensure/restore good ecological status of the investigated estuary. For the catchment to the Horsens estuary in Denmark we estimate the stream and groundwater thresholds for total nitrogen to be about 13 and 27 mg/l (~ 12 and 25 mg/l of nitrate). The shown example of deriving nitrogen threshold concentrations is for groundwater and streams in a coastal catchment discharging to a vulnerable estuary in Denmark, but the principles may be applied to large river basins with sub-catchments in several countries such as e.g. the Danube or the Rhine. In this case the relevant countries need to collaborate on derivation of nitrogen thresholds based on e.g. maximum acceptable nitrogen loadings to the Black Sea / the North Sea, and finally agree on thresholds for different parts of the river basin. Phosphorus is another nutrient which frequently results in or contributes to the eutrophication of surface waters. The transport and retention processes of total phosphorus (TP) is more complex than for nitrate (or alternatively total N), and presently we are able to establish TP thresholds for streams but not for groundwater. Derivation of TP thresholds is covered in an accompanying paper by Kronvang et al.
An industrial ecology approach to municipal solid waste ...
Municipal solid waste (MSW) can be viewed as a feedstock for industrial ecology inspired conversions of wastes to valuable products and energy. The industrial ecology principle of symbiotic processes using waste streams for creating value-added products is applied to MSW, with examples suggested for various residual streams. A methodology is presented to consider individual waste-to-energy or waste-to-product system synergies, evaluating the economic and environmental issues associated with each system. Steps included in the methodology include identifying waste streams, specific waste components of interest, and conversion technologies, plus steps for determining the economic and environmental effects of using wastes and changes due to transport, administrative handling, and processing. In addition to presenting the methodology, technologies for various MSW input streams are categorized as commercialized or demonstrated to provide organizations that are considering processes for MSW with summarized information. The organization can also follow the methodology to analyze interesting processes. Presents information useful for analyzing the sustainability of alternatives for the management of municipal solid waste.
Assessing the Role of Land Use in Watershed Nitrate Export Using Triple Oxygen Isotopes
NASA Astrophysics Data System (ADS)
Bostic, J.; Nelson, D. M.; Eshleman, K. N.
2017-12-01
Quantifying the influence of land-use patterns on the amount and source(s) of nitrate (NO3) exported from watersheds is critical for understanding and mitigating the effects of nutrient pollution on downstream waterbodies. The isotopic composition of NO3 is valuable for fingerprinting of NO3 sources, including manure and atmospheric nitrate. To assess loads, sources, and potential transformations of NO3 in the Chesapeake Bay (CB) watershed, stream samples from fourteen sub-watersheds of the CB were collected semi-monthly and during multiple storm events from October 2015-September 2016 (Water Year 2016). The watersheds range in size (500 - 127,900 ha) and in dominant land-use (forest, urban, agriculture). The samples were analyzed for nitrate concentrations and isotopes (δ15N, as well as the triple oxygen isotope composition, defined as Δ17O ≅ δ17O - 0.52 x δ18O). Stream loads of nitrate were estimated using WRTDS (Weighted Regressions on Time, Discharge, and Season). NO3 deposition (dry and wet) was fairly uniform across all watersheds (2.1 - 3.0 kg NO3-N ha-1), whereas stream NO3 varied greatly (0.6 - 11.8 kg NO3-N ha-1). Stream loads of NO3 were positively related to the percent of agricultural land (r2 = 0.67, p < 0.005) and negatively related to the percent of forested land (r2 = 0.61, p < 0.005). Preliminary isotope data indicate a positive relationship between δ15NNO3 and the proportion of agricultural land (r2 = 0.48, p < 0.0001), which suggests that nitrate inputs in predominantly agricultural watersheds are manure or pools of partially denitrified fertilizer. A positive relationship between Δ17ONO3 and the percent of forested land (r2 = 0.19, p < 0.005) suggests that forests export a greater proportion of atmospheric nitrate than other systems. Full NO3 isotope data for Water Year 2016 ( 400 samples) will be presented from all watersheds to elucidate the amount and sources of NO3 exported from a variety of land-uses.
NASA Astrophysics Data System (ADS)
Hampton, T. B.; Zarnetske, J. P.; Briggs, M. A.; Singha, K.; Day-Lewis, F. D.
2017-12-01
Many important biogeochemical processes governing both carbon and nitrogen dynamics in streams take place at the sediment-water interface (SWI). This interface is highly variable in biogeochemical function, with stream stage often influencing the magnitude and direction of water and solute exchange through the SWI. It is well known that the SWI can be an important location for carbon and nitrogen transformations, including denitrification and greenhouse gas production. The degree of mixing of carbon and nitrate, along with oxygen from surface waters, is strongly influenced by hydrologic exchange at the SWI. We hypothesize that hydrologic residence time, which is also determined by the magnitude of exchange, is a key control on the fate of nitrate at the SWI and on the end products of denitrification. Previous studies in the headwaters of the Ipswich River in MA as part of the Lotic Intersite Nitrogen Experiments (LINX II) and other long-term monitoring suggest that the Ipswich River SWI represents an important source of nitrous oxide, a potent greenhouse gas. Using a novel constant-head infiltrometer ring embedded in the stream sediments, we created four unique controlled down-welling (i.e., recharge) conditions, and tested how varying this hydrologic flux and thus the residence time distribution influenced biogeochemical function of the Ipswich River SWI. Specifically, we added isotopically-labelled 15N-nitrate to stream water during each controlled hydrologic flux experiment to quantify nitrate transformation rates, including denitrification end products, under the different hydrologic conditions. We also measured a suite of carbon and nitrogen solutes, along with dissolved oxygen conditions throughout each experiment to characterize the broader residence timescale and biogeochemical responses to the hydrologic manipulations. Initial results show that the oxic conditions of the SWI were strongly responsive to changes in hydrologic flux rates, thereby changing the redox conditions and likely the fate of the nitrate through the infiltrometer. The forthcoming 15N data will quantify the nitrate response. Overall, this study will help demonstrate how the SWI of this historically important research river transforms nitrate under variable hydrologic conditions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NSTec Environmental Management
2013-01-31
The purpose of this Special Analysis (SA) is to determine if the Oak Ridge (OR) Consolidated Edison Uranium Solidification Project (CEUSP) uranium-233 (233U) waste stream (DRTK000000050, Revision 0) is acceptable for shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada National Security Site (NNSS). The CEUSP 233U waste stream requires a special analysis because the concentrations of thorium-229 (229Th), 230Th, 232U, 233U, and 234U exceeded their NNSS Waste Acceptance Criteria action levels. The acceptability of the waste stream is evaluated by determining if performance assessment (PA) modeling provides a reasonable expectation that SLBmore » disposal is protective of human health and the environment. The CEUSP 233U waste stream is a long-lived waste with unique radiological hazards. The SA evaluates the long-term acceptability of the CEUSP 233U waste stream for near-surface disposal as a two tier process. The first tier, which is the usual SA process, uses the approved probabilistic PA model to determine if there is a reasonable expectation that disposal of the CEUSP 233U waste stream can meet the performance objectives of U.S. Department of Energy Manual DOE M 435.1-1, “Radioactive Waste Management,” for a period of 1,000 years (y) after closure. The second tier addresses the acceptability of the OR CEUSP 233U waste stream for near-surface disposal by evaluating long-term site stability and security, by performing extended (i.e., 10,000 and 60,000 y) modeling analyses, and by evaluating the effect of containers and the depth of burial on performance. Tier I results indicate that there is a reasonable expectation of compliance with all performance objectives if the OR CEUSP 233U waste stream is disposed in the Area 5 RWMS SLB disposal units. The maximum mean and 95th percentile PA results are all less than the performance objective for 1,000 y. Monte Carlo uncertainty analysis indicates that there is a high likelihood of compliance with all performance objectives. Tier II results indicate that the long-term performance of the OR CEUSP 233U waste stream is protective of human health and the environment. The Area 5 RWMS is located in one of the least populated and most arid regions of the U.S. Site characterization data indicate that infiltration of precipitation below the plant root zone at 2.5 meters (8.2 feet) ceased 10,000 to 15,000 y ago. The site is not expected to have a groundwater pathway as long as the current arid climate persists. The national security mission of the NNSS and the location of the Area 5 RWMS within the Frenchman Flat Corrective Action Unit require that access controls and land use restrictions be maintained indefinitely. PA modeling results for 10,000 to 60,000 y also indicate that the OR CEUSP 233U waste stream is acceptable for near-surface disposal. The mean resident air pathway annual total effective dose (TED), the resident all-pathways annual TED, and the acute drilling TED are less than their performance objectives for 10,000 y after closure. The mean radon-222 (222Rn) flux density exceeds the performance objective at 4,200 y, but this is due to waste already disposed at the Area 5 RWMS and is only slightly affected by disposal of the CEUSP 233U. The peak resident all-pathways annual TED from CEUSP key radionuclides occurs at 48,000 y and is less than the 0.25 millisievert performance objective. Disposal of the OR CEUSP 233U waste stream in a typical SLB trench slightly increases PA results. Increasing the depth was found to eliminate any impacts of the OR CEUSP 233U waste stream. Containers could not be shown to have any significant impact on performance due to the long half-life of the waste stream and a lack of data for pitting corrosion rates of stainless steel in soil. The results of the SA indicate that all performance objectives can be met with disposal of the OR CEUSP 233U waste stream in the SLB units at the Area 5 RWMS. The long-term performance of the OR CEUSP 233U waste stream disposed in the near surface is protective of human health and the environment. The waste stream is recommended for disposal without conditions.« less
Triska, F.J.; Kennedy, V.C.; Avanzino, R.J.; Zellweger, G.W.; Bencala, K.E.
1989-01-01
Chloride and nitrate were coinjected into the surface waters of a third-order stream for 20 d to exmaine solute retention, and the fate of nitrate during subsurface transport. A series of wells (shallow pits) 0.5-10 m from the adjacent channel were sampled to estimate the lateral interflow of water. Two subsurface return flows beneath the wetted channel were also examined. Results indicated that the capacity of the hyporheic zone for transient solute storage and as potential biological habitat varies with channel morphology, bed roughness, and permeability. A conceptual model that considers the groundwater-stream water interface as the fluvial boundary is proposed. -from Authors
NASA Astrophysics Data System (ADS)
Muguercia, Ivan
Hazardous radioactive liquid waste is the legacy of more than 50 years of plutonium production associated with the United States' nuclear weapons program. It is estimated that more than 245,000 tons of nitrate wastes are stored at facilities such as the single-shell tanks (SST) at the Hanford Site in the state of Washington, and the Melton Valley storage tanks at Oak Ridge National Laboratory (ORNL) in Tennessee. In order to develop an innovative, new technology for the destruction and immobilization of nitrate-based radioactive liquid waste, the United State Department of Energy (DOE) initiated the research project which resulted in the technology known as the Nitrate to Ammonia and Ceramic (NAC) process. However, inasmuch as the nitrate anion is highly mobile and difficult to immobilize, especially in relatively porous cement-based grout which has been used to date as a method for the immobilization of liquid waste, it presents a major obstacle to environmental clean-up initiatives. Thus, in an effort to contribute to the existing body of knowledge and enhance the efficacy of the NAC process, this research involved the experimental measurement of the rheological and heat transfer behaviors of the NAC product slurry and the determination of the optimal operating parameters for the continuous NAC chemical reaction process. Test results indicate that the NAC product slurry exhibits a typical non-Newtonian flow behavior. Correlation equations for the slurry's rheological properties and heat transfer rate in a pipe flow have been developed; these should prove valuable in the design of a full-scale NAC processing plant. The 20-percent slurry exhibited a typical dilatant (shear thickening) behavior and was in the turbulent flow regime due to its lower viscosity. The 40-percent slurry exhibited a typical pseudoplastic (shear thinning) behavior and remained in the laminar flow regime throughout its experimental range. The reactions were found to be more efficient in the lower temperature range investigated. With respect to leachability, the experimental final NAC ceramic waste form is comparable to the final product of vitrification, the technology chosen by DOE to treat these wastes. As the NAC process has the potential of reducing the volume of nitrate-based radioactive liquid waste by as much as 70 percent, it not only promises to enhance environmental remediation efforts but also effect substantial cost savings.
Innovative practices for treating waste streams containing heavy metals often involve technologies or systems that either reduce the amount of waste generated or recover reusable resources. With the land disposal of metal treatment residuals becoming less of an accepted waste man...
Lee, Kathy E.; Lorenz, David L.; Petersen, James C.; Greene, John B.
2012-01-01
The U.S. Geological Survey determined seasonal variability in nutrients, carbon, and algal biomass in 22 wadeable streams over a 1-year period during 2007 or 2008 within three geographically distinct areas in the United States. The three areas are the Upper Mississippi River Basin (UMIS) in Minnesota, the Ozark Plateaus (ORZK) in southern Missouri and northern Arkansas, and the Upper Snake River Basin (USNK) in southern Idaho. Seasonal patterns in some constituent concentrations and algal responses were distinct. Nitrate concentrations were greatest during the winter in all study areas potentially because of a reduction in denitrification rates and algal uptake during the winter, along with reduced surface runoff. Decreases in nitrate concentrations during the spring and summer at most stream sites coincided with increased streamflow during the snowmelt runoff or spring storms indicating dilution. The continued decrease in nitrate concentrations during summer potentially is because of a reduction in nitrate inputs (from decreased surface runoff) or increases in biological uptake. In contrast to nitrate concentrations, ammonia concentrations varied among study areas. Ammonia concentration trends were similar at UMIS and USNK sampling sites with winter peak concentrations and rapid decreases in ammonia concentrations by spring or early summer. In contrast, ammonia concentrations at OZRK sampling sites were more variable with peak concentrations later in the year. Ammonia may accumulate in stream water in the winter under ice and snow cover at the UMIS and USNK sites because of limited algal metabolism and increased mineralization of decaying organic matter under reducing conditions within stream bottom sediments. Phosphorus concentration patterns and the type of phosphorus present changes with changing hydrologic conditions and seasons and varied among study areas. Orthophosphate concentrations tended to be greater in the summer at UMIS sites, whereas total phosphorus concentrations at most UMIS and USNK sites peaked in the spring during runoff and then decreased through the remainder of the sampling period. Total phosphorus and orthophosphate concentrations in OZRK streams peaked during summer indicating a runoff-based source of both nutrients. Orthophosphate concentrations may increase in streams in the late summer when surface runoff composes less of total streamflow, and when groundwater containing orthophosphate becomes a more dominant source in streams during lower flows. Seston chlorophyll a concentrations were greatest early in the growing season (spring), whereas the spring runoff events coincided with reductions in benthic algal chlorophyll a biomass likely because of scour of benthic algae from the channel bottom that are entrained in the water column during that period. Nitrate, ammonia, and orthophosphate concentrations also decreased during that same period, indicating dilution in the spring during runoff events. The data from this study indicate that the source of water (surface runoff or groundwater) to a stream and the intensity of major runoff events are important factors controlling instream concentrations. Biological processes appear to affect nutrient concentrations during more stable lower flow periods in later summer, fall, and winter when residence time of water in a channel is longer, which allows more time for biological uptake and transformations. Management of nutrient conditions in streams is challenging and requires an understanding of multiple factors that affect in-stream nutrient concentrations and biological uptake and growth.
Aubert, Alice H; Thrun, Michael C; Breuer, Lutz; Ultsch, Alfred
2016-08-30
High-frequency, in-situ monitoring provides large environmental datasets. These datasets will likely bring new insights in landscape functioning and process scale understanding. However, tailoring data analysis methods is necessary. Here, we detach our analysis from the usual temporal analysis performed in hydrology to determine if it is possible to infer general rules regarding hydrochemistry from available large datasets. We combined a 2-year in-stream nitrate concentration time series (time resolution of 15 min) with concurrent hydrological, meteorological and soil moisture data. We removed the low-frequency variations through low-pass filtering, which suppressed seasonality. We then analyzed the high-frequency variability component using Pareto Density Estimation, which to our knowledge has not been applied to hydrology. The resulting distribution of nitrate concentrations revealed three normally distributed modes: low, medium and high. Studying the environmental conditions for each mode revealed the main control of nitrate concentration: the saturation state of the riparian zone. We found low nitrate concentrations under conditions of hydrological connectivity and dominant denitrifying biological processes, and we found high nitrate concentrations under hydrological recession conditions and dominant nitrifying biological processes. These results generalize our understanding of hydro-biogeochemical nitrate flux controls and bring useful information to the development of nitrogen process-based models at the landscape scale.
Impacts of Mesoscale Eddies on the Vertical Nitrate Flux in the Gulf Stream Region
NASA Astrophysics Data System (ADS)
Zhang, Shuwen; Curchitser, Enrique N.; Kang, Dujuan; Stock, Charles A.; Dussin, Raphael
2018-01-01
The Gulf Stream (GS) region has intense mesoscale variability that can affect the supply of nutrients to the euphotic zone (Zeu). In this study, a recently developed high-resolution coupled physical-biological model is used to conduct a 25-year simulation in the Northwest Atlantic. The Reynolds decomposition method is applied to quantify the nitrate budget and shows that the mesoscale variability is important to the vertical nitrate supply over the GS region. The decomposition, however, cannot isolate eddy effects from those arising from other mesoscale phenomena. This limitation is addressed by analyzing a large sample of eddies detected and tracked from the 25-year simulation. The eddy composite structures indicate that positive nitrate anomalies within Zeu exist in both cyclonic eddies (CEs) and anticyclonic eddies (ACEs) over the GS region, and are even more pronounced in the ACEs. Our analysis further indicates that positive nitrate anomalies mostly originate from enhanced vertical advective flux rather than vertical turbulent diffusion. The eddy-wind interaction-induced Ekman pumping is very likely the mechanism driving the enhanced vertical motions and vertical nitrate transport within ACEs. This study suggests that the ACEs in GS region may play an important role in modulating the oceanic biogeochemical properties by fueling local biomass production through the persistent supply of nitrate.
Water resources of the Red Lake Indian Reservation, northwestern Minnesota
Ruhl, J.F.
1991-01-01
The quality of ground water is suitable for drinking and other household uses, and the quality of the surface water generally meets U.S. Environmental Protection Agency criteria necessary for the maintenance of aquatic life. The major ions in both ground and surface water are calcium, magnesium, and bicarbonate. Lower and Upper Red Lakes are eutrophic to mesotrophic on the basis of their summer Secchi disk-transparency readings, which ranged from 2.6 to 8.2 feet. The concentration of total organic carbon in samples from Lower and Upper Red Lakes and four streams were below or, in the case of one stream, about equal to 30 milligrams per liter, which is indicative of water little affected by human activities. The sample with the highest organic carbon content was collected from a stream that drained peatlands, which were probably sources of organic matter in the runoff. The concentration of nitrite plus nitrate in samples collected from Lower and Upper Red Lakes in late summer was below 0.01 milligrams per liter, which is characteristic of water uncontaminated by animal wastes. Total phosphorus in these samples ranged from 0.01 to 0.02 milligrams per liter. Most of this phosphorus was in the particulate organic fraction because of the abundance of phytoplankton.
Saad, D.A.; Thorstenson, D.C.
1998-01-01
Ground water recharging at mid- and downgradient wells is oxic and contains dissolved nitrate, whereas the ground water discharging to the stream is anoxic and contains dissolved ammonium. Redox environments were defined at each well on the basis of relative concentrations of various dissolved redox-active species. Chemically permissible flowpaths inferred from the observed sequence of redox environments at well sites are consistent with flowpaths in the ground-water flow model. The transition from nitrate in recharging ground water to ammonium in ground water discharging to the stream suggests the possibility of nitrate reduction along the flowpath. None of the techniques employed in this study, however, were able to prove the occurrence of this reaction.
Background/Question/Methods Headwater streams can serve as important sources and sinks for nitrogen (N) for downstream receiving waters. Prior research on N removal in small streams has largely focused on growing season conditions. Here we examine the influence of headwater...
Nitrate removal and denitrification in headwater agricultural streams of the Pacific Northwest
Headwater streams can serve as important sites for nitrogen (N) removal in watersheds. Here we examine the influence of agricultural streams on watershed N export in the Willamette River Basin of western Oregon, USA, a region with mixed agricultural, urban and forestry land uses...
THE EFFECTS OF ECOSYSTEM RESTORATION ON NITROGEN PROCESSING IN AN URBAN MID-ATLANTIC PIEDMONT STREAM
Elevated nitrate levels in streams and groundwater pose human and ecological threats. The US EPA, USGS, Institute of Ecosystem Studies, and Baltimore County Dept. of Environmental Protection are collaborating on a multi-year study of the impacts of stream restoration on nitrogen...
Influence of riparian seepage zones on nitrate variability in two agricultural headwater streams
USDA-ARS?s Scientific Manuscript database
Riparian seepage zones are one of the primary pathways of groundwater transport to headwater streams. While seeps have been recognized for their contributions to streamflow, there is little information on how seeps affect stream water quality. The objective of this study was to examine the influence...
Summary of hydrologic conditions in the Reedy Creek Improvement District, central Florida
German, Edward R.
1986-01-01
The Reedy Creek Improvement is an area of about 43 square miles in southwestern Orange and northwestern Osceola Counties, Florida. A systematic program of hydrologic data collection in the Reedy Creek Improvement District and vicinity provided data for assessing the impact of development, mostly the Walt Disney World Theme Park and related development on the hydrology. Data collected include stream discharge, water quality, groundwater levels, lakes levels, and climatological. Rainfall has been less than the long-term average in the Reedy Creek Improvement District since development began in 1968. The deficient rainfall has reduced stream discharge, lowered groundwater and lake levels, and possibly affected water quality in the area. Groundwater levels and lake levels have declined since 1970. However, the coincidence of below-average rainfall with the period of development makes it impossible to assess the effect of pumping on declines. Occurrence of toxic metals does not relate to development, but distribution of insecticides and herbicides does appear to relate to development. Specific conductance, phosphorous, and nitrate concentrations have increased in Reedy Creek since 1970, probably due to disposal of treated wastes. (USGS)
Barlow, Jeannie R.; Coupe, Richard H.
2012-01-01
During April 2007 through September 2008, the USGS collected hydrogeologic and water-quality data from a site on the Bogue Phalia to evaluate the role of groundwater and surface-water interaction on the transport of nitrate to the shallow sand and gravel aquifer underlying the Mississippi Alluvial Plain in northwestern Mississippi. A two-dimensional groundwater/surface-water exchange model was developed using temperature and head data and VS2DH, a variably saturated flow and energy transport model. Results from this model showed that groundwater/surface-water exchange at the site occurred regularly and recharge was laterally extensive into the alluvial aquifer. Nitrate was consistently reported in surface-water samples (n = 52, median concentration = 39.8 μmol/L) although never detected in samples collected from in-stream piezometers or shallow monitoring wells adjacent to the stream (n = 46). These two facts, consistent detections of nitrate in surface water and no detections of nitrate in groundwater, coupled with model results that indicate large amounts of surface water moving through an anoxic streambed, support the case for denitrification and nitrate loss through the streambed.
Mary Beth Adams; James N. Kochenderfer
2007-01-01
Long-term monitoring of stream chemistry of forested watersheds on the Fernow Experimental Forest in West Virginia has been conducted to determine the effects of both human induced and natural disturbances on nutrient cycling and stream chemistry. We compare mean annual stream water pH, and nitrate (NO3), sulfate (SO4), and...
Precipitation of nitrate-cancrinite in Hanford Tank Sludge.
Buck, E C; McNamara, B K
2004-08-15
The chemistry of underground storage tanks containing high-level waste at the Hanford Site in Washington State is an area of continued research interest. Thermodynamic models have predicted the formation of analcime and clinoptilolite in Hanford tanks, rather than cancrinite; however, these predictions were based on carbonate-cancrinite. We report the first observation of a nitrate-cancrinite [possibly Na8(K,Cs)(AlSiO4)6(NO3)2 x nH2O] extracted from a Hanford tank 241-AP-101 sample that was evaporated to 6, 8, and 10 M NaOH concentrations. The nitrate-cancrinite phase formed spherical aggregates (4 microm in diameter) that consisted of platy hexagonal crystals (approximately 0.2 microm thick). Cesium-137 was concentrated in these aluminosilicate structures. These phases possessed a morphology identical to that of nitrate-cancrinite synthesized using simulant tests of nonradioactive tank waste, supporting the contention that it is possible to develop nonradioactive artificial sludges. This investigation points to the continued importance of understanding the solubility of NO3-cancrinite and related phases. Knowledge of the detailed structure of actual phases in the tank waste helps with thermodynamic modeling of tank conditions and waste processing.
Aluko, Olufemi Oludare; Sridhar, M K C
2005-06-01
Leachates are wastewater generated principally from landfills and solid waste disposal sites. Leachates emanating from municipal wastes are a major source of surface and groundwater pollution worldwide. Globally, leachates have been implicated in low yield of farm produce, developmental anomalies, low birth weights, leukemia incidence, and other cancers in communities around the site. They have also been implicated in hazards to the environment, loss of biodiversity, and contamination of water sources. At Aba-Eku in Nigeria, leachates are being discharged into the Omi Stream without treatment. A study was conducted on a method of leachate treatment that passes the leachate through constructed wetlands using Ipomoea aquatica (Forsk), a locally available plant found close to the landfill site. The aim of the study was to evolve a sustainable and cost-effective method of treatment whose effluents can be discharged into the Omi Stream with no or minimal impact. The study was descriptive and analytical in design. Samples were collected and analyzed with standard methods for pH, suspended solids (SS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammonia, nitrate, and trace metals. Raw leachates were turbid and amber in color and contained suspended solids (197.5 mg/L), ammonia (610.9 mg/L), lead (1.64 mg/L), iron (198.10 mg/L), and manganese (23.20 mg/L). When the leachates were passed through the constructed wetland with eight hours' detention time, effluents showed significant reductions in suspended solids (81.01 percent), BOD (86.03 percent), and ammonia (97.77 percent). The study shows that a constructed wetland is a feasible tool for the treatment of leachates before their disposal into the environment in Nigeria and can help safeguard environmental quality.
Denitrification and mixing in a stream-aquifer system: Effects on nitrate loading to surface water
McMahon, P.B.; Böhlke, J.K.
1996-01-01
Ground water in terrace deposits of the South Platte River alluvial aquifer near Greeley, Colorado, USA, had a median nitrate concentration of 1857 ??mol l-1. Median nitrate concentrations in ground water from adjacent floodplain deposits (468 ??mol l-1) and riverbed sediments (461 ??mol l-1), both of which are downgradient from the terrace deposits, were lower than the median concentration in the terrace deposits. The concentrations and ??15N values of nitrate and N2 in ground water indicated that denitrifying activity in the floodplain deposits and riverbed sediments accounted for 15- 30% of the difference in nitrate concentrations. Concentrations of Cl- and SiO2 indicated that mixing between river water and ground water in the floodplain deposits and riverbed sediments accounted for the remainder of the difference in nitrate concentrations. River flux measurements indicated that ground-water discharge in a 7.5 km segment of river had a nitrate load of 1718 kg N day-1 and accounted for about 18% of the total nitrate load in the river at the downstream end of that segment. This nitrate load was 70% less than the load predicted on the basis of the median nitrate concentration in the terrace deposits and assuming no denitrification or mixing in the aquifer. Water exchange between the river and aquifer caused ground water that originally discharged to the river to reenter denitrifying sediments in the riverbed and floodplain, thereby further decreasing the nitrate load in this stream-aquifer system. Results from this study indicated that denitrification and mixing within alluvial aquifer sediments may substantially decrease the nitrate load added to rivers by discharging ground water.
Milligan, Chad R.; Pope, Larry M.
2001-01-01
Improving water quality of Cheney Reservoir in south-central Kansas is an important objective of State and local water managers. The reservoir serves as a water supply for about 350,00 people in the Wichita area and an important recreational resource for the area. In 1992, a task force was formed to study and prepare a plan to identify and mitigate potential sources of stream contamination in the Cheney Reservoir watershed. This task force was established to develop stream-water-quality goals to aid in the development and implementation of best-management practices in the watershed. In 1996, the U.S. Geological Survey entered into a cooperative study with the city of Wichita to assess the water quality in the Cheney Reservoir watershed. Water-quality constituents of particular concern in the Cheney Reservoir watershed are phosphorus, nitrate, and total suspended solids. Water-quality samples were collected at five streamflow-gaging sites upstream from the reservoir and at the outflow of the reservoir. The purpose of this report is to present the results of a 4-year (1997-2000) data-collection effort to quantify the occurrence of phosphorus, nitrate, and suspended solids during base-flow, runoff, and long-term streamflow conditions (all available data for 1997-2000) and to compare these results to stream-water-quality goals established by the Cheney Reservoir Task Force. Mean concentrations of each of the constituents examined during this study exceeded the Cheney Reservoir Task Force stream-water-quality goal for at least one of the streamflow conditions evaluated. Most notably, mean base-flow and mean long-term concentrations of total phosphorus and mean base-flow concentrations of dissolved nitrate exceeded the goals of 0.05, 0.10, and 0.25 milligram per liter, respectively, at all five sampling sites upstream from the reservoir. Additionally, the long-term stream-water-quality goal for dissolved nitrate was exceeded by the mean concentration at one upstream sampling site, and the base-flow total suspended solids goal (20 milligrams per liter) and long-term total suspended solids goal (100 milligrams per liter) were each exceeded by mean concentrations at three upstream sampling sites. Generally, it seems unlikely that water-quality goals for streams in the Cheney Reservoir watershed will be attainable for mean base-flow and mean long-term total phosphorus and total suspended solids concentrations and for mean base-flow dissolved nitrate concentrations as long as current (2001) watershed conditions and practices persist. However, future changes in these conditions and practices that mitigate the transport of these consitutents may modify this conclusion.
Sequential pyrolysis of plastic to recover polystyrene, HCl and terephthalic acid
Evans, R.J.; Chum, H.L.
1995-11-07
A process is described for pyrolyzing plastic waste feed streams containing polyvinyl chloride, polyethylene terephthalate, polystyrene and polyethylene to recover polystyrene, HCl and terephthalic acid comprising: heating the plastic waste feed stream to a first temperature; adding an acid or base catalyst on an oxide or carbonate support; heating the plastic waste feed stream to pyrolyze polyethylene terephthalate and polyvinyl chloride; separating terephthalic acid or HCl; heating to a second temperature to pyrolyze polystyrene; separating styrene; heating the waste feed stream to a third temperature to pyrolyze polyethylene; and separating hydrocarbons. 83 figs.
Pastén-Zapata, Ernesto; Ledesma-Ruiz, Rogelio; Harter, Thomas; Ramírez, Aldo I; Mahlknecht, Jürgen
2014-02-01
Nitrate isotopic values are often used as a tool to understand sources of contamination in order to effectively manage groundwater quality. However, recent literature describes that biogeochemical reactions may modify these values. Therefore, data interpretation is difficult and often vague. We provide a discussion on this topic and complement the study using halides as comparative tracers assessing an aquifer underneath a sub-humid to humid region in NE Mexico. Hydrogeological information and stable water isotopes indicate that active groundwater recharge occurs in the 8000km(2) study area under present-day climatic and hydrologic conditions. Nitrate isotopes and halide ratios indicate a diverse mix of nitrate sources and transformations. Nitrate sources include organic waste and wastewater, synthetic fertilizers and soil processes. Animal manure and sewage from septic tanks were the causes of groundwater nitrate pollution within orchards and vegetable agriculture. Dairy activities within a radius of 1,000 m from a sampling point significantly contributed to nitrate pollution. Leachates from septic tanks caused nitrate pollution in residential areas. Soil nitrogen and animal waste were the sources of nitrate in groundwater under shrubland and grassland. Partial denitrification processes helped to attenuate nitrate concentration underneath agricultural lands and grassland, especially during summer months. © 2013. Published by Elsevier B.V. All rights reserved.
Groundwater pollution by nitrates from livestock wastes.
Goldberg, V M
1989-01-01
Utilization of wastes from livestock complexes for irrigation involves the danger of groundwater pollution by nitrates. In order to prevent and minimize pollution, it is necessary to apply geological-hydrogeological evidence and concepts to the situation of wastewater irrigation for the purposes of studying natural groundwater protectiveness and predicting changes in groundwater quality as a result of infiltrating wastes. The procedure of protectiveness evaluation and quality prediction is described. With groundwater pollution by nitrate nitrogen, the concentration of ammonium nitrogen noticeably increases. One of the reasons for this change is the process of denitrification due to changes in the hydrogeochemical conditions in a layer. At representative field sites, it is necessary to collect systematic stationary observations of the concentrations of nitrogenous compounds in groundwater and changes in redox conditions and temperature. PMID:2620669
Ransom, Katherine M; Grote, Mark N.; Deinhart, Amanda; Eppich, Gary; Kendall, Carol; Sanborn, Matthew E.; Sounders, A. Kate; Wimpenny, Joshua; Yin, Qing-zhu; Young, Megan B.; Harter, Thomas
2016-01-01
Groundwater quality is a concern in alluvial aquifers that underlie agricultural areas, such as in the San Joaquin Valley of California. Shallow domestic wells (less than 150 m deep) in agricultural areas are often contaminated by nitrate. Agricultural and rural nitrate sources include dairy manure, synthetic fertilizers, and septic waste. Knowledge of the relative proportion that each of these sources contributes to nitrate concentration in individual wells can aid future regulatory and land management decisions. We show that nitrogen and oxygen isotopes of nitrate, boron isotopes, and iodine concentrations are a useful, novel combination of groundwater tracers to differentiate between manure, fertilizers, septic waste, and natural sources of nitrate. Furthermore, in this work, we develop a new Bayesian mixing model in which these isotopic and elemental tracers were used to estimate the probability distribution of the fractional contributions of manure, fertilizers, septic waste, and natural sources to the nitrate concentration found in an individual well. The approach was applied to 56 nitrate-impacted private domestic wells located in the San Joaquin Valley. Model analysis found that some domestic wells were clearly dominated by the manure source and suggests evidence for majority contributions from either the septic or fertilizer source for other wells. But, predictions of fractional contributions for septic and fertilizer sources were often of similar magnitude, perhaps because modeled uncertainty about the fraction of each was large. For validation of the Bayesian model, fractional estimates were compared to surrounding land use and estimated source contributions were broadly consistent with nearby land use types.
Waste stream recycling: Its effect on water quality
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cornwell, D.A.; Lee, R.G.
1994-11-01
Waste streams recycled to the influent of a water treatment plant typically contain contaminants at concentrations that are of concern. These contaminants may include giardia and Cryptosporidium, trihalomethanes, manganese, and assimilable organic carbon. This research shows that proper management--treatment, equalization, and monitoring--of the waste streams can render them suitable for recycling in many situations.
Ruhl, J.F.
1995-01-01
Upgradient to downgradient mean or individual nitrogen isotope δ15N values in %o (delta units in parts per thousand) determined for sampled monitoring wells along the direction of ground-water flow through the five land-use settings were: (1) 5.1 %o and 4.0 %o for the feedlot and adjacent manured field; (2) 1.1 %o and 0.9 %o for the cultivated croplands irrigated with waste water; (3) 3.8 %o and 2.7 %o for the cultivated croplands irrigated with ground water; (4) 3.4 %o and 4.9 %o for the residential development; and (5) 1.7 %o and 3.0 %o for the three waste-water lagoons. Nitrate from fertilizer appeared to have been present in ground water at the waste-water lagoons, cultivated croplands irrigated with waste water, and cultivated croplands irrigated with ground water. Nitrate from soil organic matter rather than from animal waste appeared to have been present in ground water at the feedlot and adjacent manured field.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taylor-Pashow, Kathryn M. L.; McCabe, Daniel J.; Nash, Charles A.
Vitrification of Low Activity Waste in the Hanford Waste Treatment and Immobilization Plant generates a condensate stream from the off-gas processes. Components in this stream are partially volatile and accumulate to high concentrations through recycling, which impacts the waste glass loading and facility throughput. The primary radionuclide that vaporizes and accumulates in the stream is 99Tc. This program is investigating Tc removal via reductive precipitation with stannous chloride to examine the potential for diverting this stream to an alternate disposition path. As a result, research has shown stannous chloride to be effective, and this paper describes results of recent experimentsmore » performed to further mature the technology.« less
Taylor-Pashow, Kathryn M. L.; McCabe, Daniel J.; Nash, Charles A.
2017-03-16
Vitrification of Low Activity Waste in the Hanford Waste Treatment and Immobilization Plant generates a condensate stream from the off-gas processes. Components in this stream are partially volatile and accumulate to high concentrations through recycling, which impacts the waste glass loading and facility throughput. The primary radionuclide that vaporizes and accumulates in the stream is 99Tc. This program is investigating Tc removal via reductive precipitation with stannous chloride to examine the potential for diverting this stream to an alternate disposition path. As a result, research has shown stannous chloride to be effective, and this paper describes results of recent experimentsmore » performed to further mature the technology.« less
Schmitt, Elliott; Bura, Renata; Gustafson, Rick; Cooper, Joyce; Vajzovic, Azra
2012-01-01
There is little research literature on the conversion of lignocellulosic rich waste streams to ethanol, and even fewer have investigated both the technical aspects and environmental impacts together. This study assessed technical and environmental challenges of converting three lignocellulosic waste streams to ethanol: municipal solid waste (MSW), low grade mixed waste paper (MWP), and organic yard waste (YW). Experimental results showed high conversion yields for all three streams using suitable conversion methods. Environmental impacts are highly dependent on conversion technology, and process conditions used. Life cycle assessment results showed that both chemicals production and waste collection are important factors to be included within a waste-to-ethanol study. Copyright © 2011 Elsevier Ltd. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Riparian seepage zones in headwater agricultural watersheds represent important sources of nitrate-nitrogen (NO3-N) to surface waters, often connecting N-rich groundwater systems to streams. In this study, we examined how NO3-N concentrations in seep and stream water were affected by NO3-N processin...
Frank S. Gilliam; Mary Beth Adams
2011-01-01
This study examined changes in stream and soil water NO3- and their relationship to temporal and spatial patterns of NO3- in soil solution of watersheds at the Fernow Experimental Forest, West Virginia. Following tenfold increases in stream NO3
Hatzell, H.H.
1995-01-01
Waste-disposal areas such as chicken-house floors, litter stockpiles, fields that receive applications of litter, and dead-chicken pits are potential sources of nitrates and other chemical constituents in downward-percolating recharge water. Broiler- farms in north-central Florida are concentrated in a region where the Upper Floridan aquifer is unconfined and susceptible to contamination. Eighteen monitoring wells installed at five sites were sampled quarterly from March 1992 through January 1993. Increases in median concentrations of constituents relative to an upgradient well were used to determine the source of the nitrate at two sites. At these sites, increases in the median concentrations of nitrate as nitrogen in ground water in the vicinity of waste-disposal areas at these sites were: 5.4 mg/L for one chicken house; 9.0 mg/L for a second chicken house; 2.0 mg/L for a fallow field that received an application of litter; and, 2.0 mg/L for a dead-chicken pit. At the three remaining sites where the direction of local ground-water flow could not be ascertained, the sources of concentrations of nitrate and other constituents could not be determined. However, median nitrate concentrations in the vicinity of waste-disposal areas at these sites were: 45.5 mg/L for a set of two chicken houses; 3.0 mg/L for a stockpile area; and 2.1 mg/L for a hayfield that received an application of litter. The nitrate concentration in ground water in the vicinity of a field that had previously received heavy applications of litter increased from 3.0 mg/L to 105 mg/L approximately 4 months after receiving an application of commercial fertilizer. Increases in concentrations of organic nitrogen in ground water in the vicinity of waste-disposal areas may be related to the decomposition of litter and subsequent movement with downward percolating recharge water.(USGS)
Groundwater levels and water quality during a 96-hour aquifer test in Pickaway County, Ohio, 2012
Haefner, Ralph J.; Runkle, Donna L.; Mailot, Brian E.
2014-01-01
During October–November 2012, a 96-hour aquifer test was performed at a proposed well field in northern Pickaway County, Ohio, to investigate groundwater with elevated nitrate concentrations. Earlier sampling done by the City of Columbus revealed that some wells had concentrations of nitrate that approached 10 milligrams per liter (mg/L), whereas other wells and the nearby Scioto River had concentrations from 2 to 6 mg/L. The purpose of the current test was to examine potential changes in water quality that may be expected if the site was developed into a public water-supply source; therefore, water-transmitting properties determined during a previous test were not determined a second time. Before and during the test, water-level data and water-quality samples were obtained from observation wells while a test production well was pumped at 1,300 gallons per minute. Before the test, local groundwater levels indicated that groundwater was being discharged to the nearby Scioto River, but during the test, the stream was losing streamflow owing to infiltration. Water levels declined in the pumping well, in adjacent observation wells, and in a nearby streambed piezometer as pumping commenced. The maximum drawdown in the pumping well was 29.75 feet, measured about 95 hours after pumping began. Water-quality data, including analyses for field parameters, major and trace elements, nutrients, and stable isotopes of oxygen and nitrogen in nitrate, demonstrated only small variations before and during the test. Concentrations of nitrate in five samples from the pumping well ranged from about 5.10 to 5.42 mg/L before and during the test, whereas concentrations of nitrate in five samples on or about the same sampling dates and times at a monitoring site on the Scioto River adjacent to the pumping well ranged from 3.46 to 4.97 mg/L. Water from two nearby observation wells had nitrate concentrations approaching 10 mg/L, which is the U.S. Environmental Protection Agency’s Maximum Contaminant Level for nitrate. Analysis of isotopes of oxygen and nitrogen in nitrate indicated that the source of nitrate is most likely soil nitrogen and fertilizer, with some denitrification and (or) mixing with some manure and septic waste derived from upstream wastewater-treatment facilities.
Long-term changes in nitrate conditions over the 20th century in two Midwestern Corn Belt streams
Kelly, Valerie J.; Stets, Edward G.; Crawford, Charles G.
2015-01-01
Long-term changes in nitrate concentration and flux between the middle of the 20th century and the first decade of the 21st century were estimated for the Des Moines River and the Middle Illinois River, two Midwestern Corn Belt streams, using a novel weighted regression approach that is able to detect subtle changes in solute transport behavior over time. The results show that the largest changes in flow-normalized concentration and flux occurred between 1960 and 1980 in both streams, with smaller or negligible changes between 1980 and 2004. Contrasting patterns were observed between (1) nitrate export linked to non-point sources, explicitly runoff of synthetic fertilizer or other surface sources and (2) nitrate export presumably associated with point sources such as urban wastewater or confined livestock feeding facilities, with each of these modes of transport important under different domains of streamflow. Surface runoff was estimated to be consistently most important under high-flow conditions during the spring in both rivers. Nitrate export may also have been considerable in the Des Moines River even under some conditions during the winter when flows are generally lower, suggesting the influence of point sources during this time. Similar results were shown for the Middle Illinois River, which is subject to significant influence of wastewater from the Chicago area, where elevated nitrate concentrations were associated with at the lowest flows during the winter and fall. By modeling concentration directly, this study highlights the complex relationship between concentration and streamflow that has evolved in these two basins over the last 50 years. This approach provides insights about changing conditions that only become observable when stationarity in the relationship between concentration and streamflow is not assumed.
Stream-subsurface nutrient dynamics in a groundwater-fed stream
NASA Astrophysics Data System (ADS)
Rezanezhad, F.; Niederkorn, A.; Parsons, C. T.; Van Cappellen, P.
2015-12-01
The stream-riparian-aquifer interface plays a major role in the regional flow of nutrients and contaminants due to a strong physical-chemical gradient that promotes the transformation, retention, elimination or release of biogenic elements. To better understand the effect of the near-stream zones on stream biogeochemistry, we conducted a field study on a groundwater-fed stream located in the rare Charitable Research Reserve, Cambridge, Ontario, Canada. This study focused on monitoring the spatial and temporal distributions of nutrient elements within the riparian and hyporheic zones of the stream. Several piezometer nests and a series of passive (diffusion) water samplers, known as peepers, were installed along longitudinal and lateral transects centered on the stream to obtain data on the groundwater chemistry. Groundwater upwelling along the stream resulted in distinctly different groundwater types and associated nitrate concentrations between small distances in the riparian zone (<4m). After the upstream source of the stream surface water, concentrations of nutrients (NO3-, NH4+, SO42- and carbon) did not significantly change before the downstream outlet. Although reduction of nitrate and sulphate were found in the riparian zone of the stream, this did not significantly influence the chemistry of the adjacent stream water. Also, minimal retention in the hyporheic zones limited reduction of reactive compounds (NO3- and SO42-) within the stream channel. The results showed that the dissolved organic carbon (DOC) and residence time of water in the hyporheic zone and in surface water limited denitrification.
NASA Technical Reports Server (NTRS)
Anilkumar, A.; Grugel, R. N.; Bhowmick, J.; Wang, T.
2004-01-01
Experiments to suppress thermocapillary oscillations using high-frequency vibrations were carried out in sodium nitrate floating half-zones. Such a half-zone is formed by melting one end of a vertically held sodium nitrate crystal rod in contact with a hot surface at the top. Thermocapillary convection occurs in the melt because of the temperature gradient at the free surface of the melt. In the experiments, when thermocapillary oscillations occurred, the bottom end of the crystal rod was vibrated at a high frequency to generate a streaming flow in a direction opposite to that of the thermocapillary convection. It is observed that, by generating a sufficiently strong streaming flow, the thermocapillary flow can be offset enough such that the associated thermocapillary oscillations can be quenched.
Moix, Matthew W.; Barks, C. Shane; Funkhouser, Jaysson E.
2003-01-01
Osage and Prairie Creeks in Benton County, Arkansas, were studied between July 24 and July 26, 2001, to describe the surface-water quality and the streamflow gains and losses along sections of each mainstem. The creeks are located in northwestern Arkansas. Water-quality samples were collected at 12 surface-water sites on the mainstem and at 6 points of inflow for Osage Creek, and at 9 surface-water sites on the mainstem and at 4 points of inflow for Prairie Creek. Water-quality analyses were performed by Rogers Water Utilities and the Arkansas Water Resources Laboratory. Streamflow measurements were made along the mainstem of each creek and at points of inflow (prior to confluence with the mainstem) to identify gaining and losing reaches. Water-quality data collected for Osage Creek indicated that dissolved ammonia concentrations were within the typical range of concentrations measured for streams in the Springfield and Salem Plateaus. Nitrite plus nitrate and total phosphorus concentrations were within the range of concentrations measured for several streams in the western part of the Springfield and Salem Plateaus. Total phosphorus concentrations measured on the mainstem of Osage Creek were higher downstream from the Rogers wastewater-treatment plant than upstream from the wastewater-treatment plant. Water-quality data collected for Prairie Creek indicated that dissolved ammonia concentrations measured for three mainstem sites were above the typical level of dissolved ammonia concentrations measured for streams in the Springfield and Salem Plateaus. High concentrations of dissolved ammonia measured at these sites might be indicative of sewage disposal or organic waste. Most concentrations of nitrite plus nitrate for Prairie Creek were above the range measured for some of the least-disturbed streams of the Ozark Highlands ecoregion but were within the range that is typical for several streams in the western part of the Springfield and Salem Plateaus. Total phosphorus concentrations were below or within the range that is typical for several streams in the western part of the Springfield and Salem Plateaus with elevated concentrations measured at two sties. Elevated concentrations of total phosphorus measured might be indicative of sewage or animal metabolic waste. Identification of losing and gaining reaches indicates that interaction exists between the local shallow unconfined ground-water aquifer and surface flow in Osage and Prairie Creeks. Measured streamflow for the mainstem of Osage Creek ranged from 2.34 to 19.1 cubic feet per second during this study. Streamflow measured at the beginning of the study reach for Osage Creek was 2.34 cubic feet per second, and streamflow measured at the downstream end of the study reach was 15.7 cubic feet per second. One losing and two gaining reaches were identified on the mainstem of Osage Creek with a net gain of 3.58 cubic feet per second upstream from the wastewater-treatment plant. Measured streamflow for the mainstem of Prairie Creek ranged from 0 to 3.17 cubic feet per second during this study. Streamflow measured at the beginning of the study reach for Prairie Creek was 0.44 cubic feet per second, and the stream bed was dry at the downstream end of the study reach. Three losing and two gaining reaches were identified on the mainstem of Prairie Creek with a net loss of 3.06 cubic feet per second.
Herbicides and nitrate in near-surface aquifers in the midcontinental United States, 1991
Kolpin, Dana W.; Burkart, Michael R.; Thurman, E. Michael
1994-01-01
Hydrogeologic factors, land use, agricultural practices, local features, and water chemistry were analyzed for possible relation to herbicide and excess-nitrate detections. Herbicides and excess nitrate were detected more frequently in near-surface unconsolidated aquifers than in nearsurface bedrock aquifers. The depth to the top of the aquifer was inversely related to the frequency of detection of herbicides and excess nitrate. The proximity of streams to sampled wells also affected the frequency of herbicide detection. Significant seasonal differences were determined for the frequency of herbicide detection, but not for the frequency of excess nitrate.
Whole-stream response to nitrate loading in three streams draining agricultural landscapes
Duff, J.H.; Tesoriero, A.J.; Richardson, W.B.; Strauss, E.A.; Munn, M.D.
2008-01-01
Physical, chemical, hydrologic, and biologic factors affecting nitrate (NO3 −) removal were evaluated in three agricultural streams draining orchard/dairy and row crop settings. Using 3-d “snapshots” during biotically active periods, we estimated reach-level NO3 − sources, NO3 − mass balance, in-stream processing (nitrification, denitrification, and NO3 − uptake), and NO3 − retention potential associated with surface water transport and ground water discharge. Ground water contributed 5 to 11% to stream discharge along the study reaches and 8 to 42% of gross NO3 − input. Streambed processes potentially reduced 45 to 75% of ground water NO3 − before discharge to surface water. In all streams, transient storage was of little importance for surface water NO3 − retention. Estimated nitrification (1.6–4.4 mg N m−2 h−1) and unamended denitrification rates (2.0–16.3 mg N m−2 h−1) in sediment slurries were high relative to pristine streams. Denitrification of NO3 − was largely independent of nitrification because both stream and ground water were sources of NO3 − Unamended denitrification rates extrapolated to the reach-scale accounted for <5% of NO3 − exported from the reaches minimally reducing downstream loads. Nitrate retention as a percentage of gross NO3 − inputs was >30% in an organic-poor, autotrophic stream with the lowest denitrification potentials and highest benthic chlorophyll a, photosynthesis/respiration ratio, pH, dissolved oxygen, and diurnal NO3 − variation. Biotic processing potentially removed 75% of ground water NO3 − at this site, suggesting an important role for photosynthetic assimilation of ground water NO3 − relative to subsurface denitrification as water passed directly through benthic diatom beds.
NASA Astrophysics Data System (ADS)
Silva, S. R.; Kendall, C.; Young, M. B.; Stringfellow, W. T.; Borglin, S. E.; Kratzer, C. R.; Dahlgren, R. A.; Schmidt, C.; Rollog, M. E.
2007-12-01
Many competing demands have been placed on the San Joaquin River including deep water shipping, use as agricultural and drinking water, transport of agricultural and urban runoff, and recreation. These long-established demands limit the management options and increase the importance of understanding the river dynamics. The relationships among sources of water, nitrate, and algae in the San Joaquin River must be understood before management decisions can be made to optimize aquatic health. Isotopic analyses of water samples collected along the San Joaquin River in 2005-2007 have proven useful in assessing these relationships: sources of nitrate, the productivity of the San Joaquin River, and the relationship between nitrate and algae in the river. The San Joaquin River receives water locally from wetlands and agricultural return flow, and from three relatively large tributaries whose headwaters are in the Sierra Nevada. The lowest nitrate concentrations occur during periods of high flow when the proportion of water from the Sierra Nevada is relatively large, reflecting the effect of dilution from the big tributaries and indicating that a large fraction of the nitrate is of local origin. Nitrogen isotopes of nitrate in the San Joaquin River are relatively high (averaging about 12 per mil), suggesting a significant source from animal waste or sewage and/or the effects of denitrification. The d15N of nitrate varies inversely with concentration, indicating that these high isotopic values are also a local product. The d15N values of nitrate from most of the local tributaries is lower than that in the San Joaquin suggesting that nitrate from these tributaries does not account for a significant fraction of nitrate in the river. The source of the non-tributary nitrate must be either small unmeasured surface inputs or groundwater. To investigate whether groundwater might be a significant source of nitrate to the San Joaquin River, groundwater samples are being collected monthly from over 20 bank and in-stream wells. Preliminary data suggest that much of the groundwater nitrate has been variably denitrified thereby increasing its d15N values, but not by enough to account for the high d15N values in the river nitrate. The d15N of algae in the San Joaquin reflects the high values of the nitrate in the river indicating (1) that the San Joaquin is productive despite its relatively high opacity, (2) that the algae use the nitrate as a primary nutrient source, and (3) that the concentrations of algae in the San Joaquin are not principally dependent on algae from the tributaries being flushed into the river as has been suggested. The sources of nitrate to the San Joaquin River must be identified if algae production is to be controlled and hypoxic conditions in the downstream reaches eliminated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shott, Gregory
This special analysis (SA) evaluates whether the Idaho National Laboratory (INL) Waste Associated with the Unirradiated Light Water Breeder Reactor (LWBR) waste stream (INEL167203QR1, Revision 0) is suitable for shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada National Security Site (NNSS). Disposal of the INL Waste Associated with the Unirradiated LWBR waste meets all U.S. Department of Energy (DOE) Manual DOE M 435.1-1, “Radioactive Waste Management Manual,” Chapter IV, Section P performance objectives (DOE 1999). The INL Waste Associated with the Unirradiated LWBR waste stream is recommended for acceptance with the conditionmore » that the total uranium-233 ( 233U) inventory be limited to 2.7E13 Bq (7.2E2 Ci).« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taylor-Pashow, Kathryn M.L.; Poirier, Michael; McCabe, Daniel J.
The Low Activity Waste (LAW) vitrification facility at the Hanford Waste Treatment and Immobilization Plant (WTP) will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The plan for disposition of this stream during baseline operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. The primary reason to recycle this stream is so that the semi-volatile 99Tc isotope eventually becomes incorporated into the glass. This stream also contains non-radioactive salt components that are problematic in the melter,more » so diversion of this stream to another process would eliminate recycling of these salts and would enable simplified operation of the LAW melter and the Pretreatment Facilities. This diversion from recycling this stream within WTP would have the effect of decreasing the LAW vitrification mission duration and quantity of glass waste. The concept being tested here involves removing the 99Tc so that the decontaminated aqueous stream, with the problematic salts, can be disposed elsewhere.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taylor-Pashow, Kathryn M. L.; McCabe, Daniel J.; Pareizs, John M.
The Low Activity Waste (LAW) vitrification facility at the Hanford Waste Treatment and Immobilization Plant (WTP) will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the offgas system. The plan for disposition of this stream during baseline operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. The primary reason to recycle this stream is so that the semi-volatile 99Tc isotope eventually becomes incorporated into the glass. This stream also contains non-radioactive salt components that are problematic in the melter,more » so diversion of this stream to another process would eliminate recycling of these salts and would enable simplified operation of the LAW melter and the Pretreatment Facilities. This diversion from recycling this stream within WTP would have the effect of decreasing the LAW vitrification mission duration and quantity of glass waste. The concept being tested here involves removing the 99Tc so that the decontaminated aqueous stream, with the problematic salts, can be disposed elsewhere.« less
Using Financial Incentives to Manage the Solid Waste Stream.
ERIC Educational Resources Information Center
Spindler, Charles J.
1991-01-01
This paper reviews two approaches to solid waste stream management that encourage recycling in the beverage industry, a model categorizing public policies directed at diverting postconsumer waste from the waste system, and industry initiatives in the context of these policies. Preemptive and compelled partnerships represent innovations in…
Goeller, Brandon C; Febria, Catherine M; Harding, Jon S; McIntosh, Angus R
2016-05-01
Around the world, artificially drained agricultural lands are significant sources of reactive nitrogen to stream ecosystems, creating substantial stream health problems. One management strategy is the deployment of denitrification enhancement tools. Here, we evaluate the factors affecting the potential of denitrifying bioreactors to improve stream health and ecosystem services. The performance of bioreactors and the structure and functioning of stream biotic communities are linked by environmental parameters like dissolved oxygen and nitrate-nitrogen concentrations, dissolved organic carbon availability, flow and temperature regimes, and fine sediment accumulations. However, evidence of bioreactors' ability to improve waterway health and ecosystem services is lacking. To improve the potential of bioreactors to enhance desirable stream ecosystem functioning, future assessments of field-scale bioreactors should evaluate the influences of bioreactor performance on ecological indicators such as primary production, organic matter processing, stream metabolism, and invertebrate and fish assemblage structure and function. These stream health impact assessments should be conducted at ecologically relevant spatial and temporal scales. Bioreactors have great potential to make significant contributions to improving water quality, stream health, and ecosystem services if they are tailored to site-specific conditions and implemented strategically with land-based and stream-based mitigation tools within watersheds. This will involve combining economic, logistical, and ecological information in their implementation. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
Effect of irrigation and winery waste compost rates in nitrate leaching in vulnerable zones
NASA Astrophysics Data System (ADS)
Requejo, Maria Isabel; Castellanos, Maria Teresa; Villena, Raquel; Ribas, Francisco; Jesús Cabello, Maria; Arce, Augusto; Cartagena, Maria Carmen
2013-04-01
The winery industry is widespread in Spain (3,610,000 tonnes of wine in 2010 (FAO, 2010)), and generates wastes characterized by a high content of organic matter, a notable content in macronutrients and low heavy-metals. These organic wastes could be used for agricultural purposes after a correct stabilization process (e.g. composting).The addition of these organic wastes requires a correct management, especially on semiarid cropped areas of central Spain where environmental degradation of water supplies with high N loads is observed. An integrated optimization of both applied compost dose and amount of irrigation is important to ensure optimum yields and minimum nitrate leaching losses. The purpose of this work was to study the effect of the application of winery waste compost as fertilizer in a melon crop cultivated with different drip irrigation rates. The field experiment was carried out in Ciudad Real, designated "vulnerable zone" by the "Nitrates Directive" 91/676/CEE. Melon crop has been traditionally cultivated in this area with high inputs of water and fertilizers, but no antecedents of application of winery wastes are known. Beside the control treatment (D0), three doses of compost were applied: 6.7 (D1), 13.3 (D2) and 20 T/ha(D3).Irrigation treatments consisted of applying a 100% ETc and an excess irrigation of 120% ETc. The soil was a shallow sandy-loam (Petrocalcic Palexeralfs), with 0.6 m depth and a discontinuous petrocalcic horizon between 0.6 and 0.7 m. Drainage and nitrate concentration on the soil solution were measured weekly to determine N leached during the crop period. Crop yield was also followed by harvesting plots when a significant number of fruits were fully matured. A comparison between nitrate leached and crop production among different treatments and irrigation rates are presented. Acknowledgements: This project has been supported by INIA-RTA2010-00110-C03-01.
Barney, Gary S.; Brownell, Lloyd E.
1977-01-01
A method for converting sodium nitrate-containing, caustic, radioactive wastes to a solid, relatively insoluble, thermally stable form is provided and comprises the steps of reacting powdered aluminum silicate clay, e.g., kaolin, bentonite, dickite, halloysite, pyrophyllite, etc., with the sodium nitrate-containing radioactive wastes which have a caustic concentration of about 3 to 7 M at a temperature of 30.degree. C to 100.degree. C to thereby entrap the dissolved radioactive salts in the aluminosilicate matrix. In one embodiment the sodium nitrate-containing, caustic, radioactive liquid waste, such as neutralized Purex-type waste, or salts or oxide produced by evaporation or calcination of these liquid wastes (e.g., anhydrous salt cake) is converted at a temperature within the range of 30.degree. C to 100.degree. C to the solid mineral form-cancrinite having an approximate chemical formula 2(NaAlSiO.sub.4) .sup.. xSalt.sup.. y H.sub.2 O with x = 0.52 and y = 0.68 when the entrapped salt is NaNO.sub.3. In another embodiment the sodium nitrate-containing, caustic, radioactive liquid is reacted with the powdered aluminum silicate clay at a temperature within the range of 30.degree. C to 100.degree. C, the resulting reaction product is air dried eitheras loose powder or molded shapes (e.g., bricks) and then fired at a temperature of at least 600.degree. C to form the solid mineral form-nepheline which has the approximate chemical formula of NaAlSiO.sub.4. The leach rate of the entrapped radioactive salts with distilled water is reduced essentially to that of the aluminosilicate lattice which is very low, e.g., in the range of 10.sup.-.sup.2 to 10.sup.-.sup.4 g/cm.sup.2 -- day for cancrinite and 10.sup.-.sup.3 to 10.sup.-.sup.5 g/cm.sup.2 -- day for nepheline.
Walker, Darrel D.; Ebra, Martha A.
1987-01-01
High efficiency removal of technetium values from a nuclear waste stream is achieved by addition to the waste stream of a precipitant contributing tetraphenylphosphonium cation, such that a substantial portion of the technetium values are precipitated as an insoluble pertechnetate salt.
Vitzthum von Eckstaedt, Sebastian; Charles, Wipa; Ho, Goen; Cord-Ruwisch, Ralf
2016-02-01
A novel biofilter that removes ammonia from air streams and converts it to nitrogen gas has been developed and operated continuously for 300 days. The ammonia from the incoming up-flow air stream is first absorbed into water and the carrier material, zeolite. A continuous gravity reflux of condensed water from the exit of the biofilter provides moisture for nitrifying bacteria to develop and convert dissolved ammonia (ammonium) to nitrite/nitrate. The down-flow of the condensed water reflux washes down nitrite/nitrate preventing ammonium and nitrite/nitrate accumulation at the top region of the biofilter. The evaporation caused by the inflow air leads to the accumulation of nitrite to extremely high concentrations in the bottom of the biofilter. The high nitrite concentrations favour the spontaneous chemical oxidation of ammonium by nitrite to nitrogen (N2). Tests showed that this chemical reaction was catalysed by the zeolite filter medium and allowed it to take place at room temperature. This study shows that ammonia can be removed from air streams and converted to N2 in a fully aerated single step biofilter. The process also overcomes the problem of microorganism-inhibition and resulted in zero leachate production. Copyright © 2015 Elsevier Ltd. All rights reserved.
2007 SB14 Source Reduction Plan/Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chang, L
2007-07-24
Aqueous solutions (mixed waste) generated from various LLNL operations, such as debris washing, sample preparation and analysis, and equipment maintenance and cleanout, were combined for storage in the B695 tank farm. Prior to combination the individual waste streams had different codes depending on the particular generating process and waste characteristics. The largest streams were CWC 132, 791, 134, 792. Several smaller waste streams were also included. This combined waste stream was treated at LLNL's waste treatment facility using a vacuum filtration and cool vapor evaporation process in preparation for discharge to sanitary sewer. Prior to discharge, the treated waste streammore » was sampled and the results were reviewed by LLNL's water monitoring specialists. The treated solution was discharged following confirmation that it met the discharge criteria. A major source, accounting for 50% for this waste stream, is metal machining, cutting and grinding operations in the engineering machine shops in B321/B131. An additional 7% was from similar operations in B131 and B132S. This waste stream primarily contains metal cuttings from machined parts, machining coolant and water, with small amounts of tramp oil from the machining and grinding equipment. Several waste reduction measures for the B321 machine shop have been taken, including the use of a small point-of-use filtering/tramp-oil coalescing/UV-sterilization coolant recycling unit, and improved management techniques (testing and replenishing) for coolants. The recycling unit had some operational problems during 2006. The machine shop is planning to have it repaired in the near future. A major source, accounting for 50% for this waste stream, is metal machining, cutting and grinding operations in the engineering machine shops in B321/B131. An additional 7% was from similar operations in B131 and B132S. This waste stream primarily contains metal cuttings from machined parts, machining coolant and water, with small amounts of tramp oil from the machining and grinding equipment. Several waste reduction measures for the B321 machine shop have been taken, including the use of a small point-of-use filtering/tramp-oil coalescing/UV-sterilization coolant recycling unit, and improved management techniques (testing and replenishing) for coolants. The recycling unit had some operational problems during 2006. The machine shop is planning to have it repaired in the near future. Quarterly waste generation data prepared by the Environmental Protection Department's P2 Team are regularly provided to engineering shops as well as other facilities so that generators can track the effectiveness of their waste minimization efforts.« less
Hydrogeologic controls on nitrate transport in a small agricultural catchment, Iowa
Schilling, K.E.; Tomer, M.D.; Zhang, Y.-K.; Weisbrod, T.; Jacobson, P.; Cambardella, C.A.
2007-01-01
Effects of subsurface deposits on nitrate loss in stream riparian zones are recognized, but little attention has been focused on similar processes occurring in upland agricultural settings. In this paper, we evaluated hydrogeologic controls on nitrate transport processes occurring in a small 7.6 ha Iowa catchment. Subsurface deposits in the catchment consisted of upland areas of loess overlying weathered pre-Illinoian till, drained by two ephemeral drainageways that consisted of Holocene-age silty and organic rich alluvium. Water tables in upland areas fluctuated more than 4 m per year compared to less than 0.3 m in the drainageway. Water quality patterns showed a distinct spatial pattern, with groundwater in the drainageways having lower nitrate concentrations (10 mg L-1) as wells as lower pH, dissolved oxygen and redox, and higher ammonium and dissolved organic carbon levels. Several lines of evidence suggested that conditions are conducive for denitrification of groundwater flowing from uplands through the drainageways. Field-measured nitrate decay rates in the drainageways (???0.02 day-1) were consistent with other laboratory studies and regional patterns. Results from MODFLOW and MT3DMS simulations indicated that soils in the ephemeral drainageways could process all upland groundwater nitrate flowing through them. However, model-simulated tile drainage increased both water flux and nitrate loss from the upland catchment. Study results suggest that ephemeral drainageways can provide a natural nitrate treatment system in our upland glaciated catchments, offering management opportunities to reduce nitrate delivery to streams. Copyright 2007 by the American Geophysical Union.
Stream-Groundwater Interaction Buffers Seasonal Changes in Urban Stream Water Quality
NASA Astrophysics Data System (ADS)
Ledford, S. H.; Lautz, L. K.
2013-12-01
Urban streams in the northeastern United States have large road salt inputs during winter, increased nonpoint sources of inorganic nitrogen, and decreased short-term and permanent storage of nutrients. Meadowbrook Creek, a first order stream in Syracuse, New York, flows along a negative urbanization gradient, from a channelized and armored stream running through the middle of a roadway to a pool-riffle stream meandering through a broad, vegetated floodplain with a riparian aquifer. In this study we investigated how reconnection to groundwater and introduction of riparian vegetation impacted surface water chemistry by making bi-weekly longitudinal surveys of stream water chemistry in the creek from May 2012 until June 2013. Chloride concentrations in the upstream, urban reach of Meadowbrook Creek were strongly influenced by discharge of road salt to the creek during snow melt events in winter and by the chemistry of water draining an upstream retention basin in summer. Chloride concentrations ranged from 161.2 mg/L in August to 2172 mg/L in February. Chloride concentrations in the downstream, 'connected' reach had less temporal variation, ranging from 252.0 mg/L in August to 1049 mg/L in January, and were buffered by groundwater discharge, as the groundwater chloride concentrations during the sampling period ranged from 84.0 to 655.4 mg/L. Groundwater discharge resulted in higher chloride concentrations in summer and lower concentrations in winter in the connected reach relative to the urban reach, minimizing annual variation. In summer, there was little-to-no nitrate in the urban reach due to a combination of limited sources and high primary productivity. In contrast, during the summer, nitrate concentrations reached over 1 mg N/L in the connected reach due to the presence of riparian vegetation and lower nitrate uptake due to cooler temperatures and shading. During the winter, when temperatures fell below freezing, nitrate concentrations in the urban reach increased to around 0.58 mg N/L, but were still lower than the connected reach, which averaged 0.88 mg N/L. Groundwater discharge rates were measured longitudinally along the creek during a constant rate Rhodamine WT injection and also confirmed qualitatively by longitudinal changes in stream sulfate and δ18O. The buffering capability of groundwater discharge in urban systems has implications for managers trying to mitigate the effects of urbanization on surface water.
NASA Astrophysics Data System (ADS)
Dodds, W. K.; Tromboni, F.; Neres-Lima, V.; Zandoná, E.; Moulton, T. P.
2016-12-01
While whole-stream measures of metabolism and uptake have become common methods to characterize biogeochemical transport and processing, less is known about how nitrogen (N) uptake, gross primary production (GPP) and ecosystem respiration (ER) covary among different stream substrata as smaller scales. We measured 15N ammonium and nitrate uptake seperately, and GPP and ER of ecosystem compartments (leaves, epilithon, sand-associated biota and macrophytes) in closed circulating chambers in three streams/ rivers of varied size. The streams drain pristine Brazilian Atlantic Rainforest watersheds and are all within a few km of eachother. The smallest stream had dense forest canopy cover; the largest river was almost completely open. GPP could not be detected in the closed canopy stream. Epilithon (biofilms on rocks) was a dominant compartment for GPP and N uptake in the two open streams, and macrophytes rivaled epilithon GPP and N uptake rates in the most open stream. Even though leaves covered only 1-3% of the stream bottom, they could account for around half of all the ER in the streams but almost no N uptake. Sand had minimal rates of N uptake, GPP and R associated with it in all streams due to relatively low organic material content. The data suggest that N uptake, GPP and ER of different substrata are not closely linked over relatively small spatial (dm) scales, and that different biogeochemical processes may map to different hot and cool spots for ecosystem rates.
Weldon, Mark B.; Hornbuckle, Keri C.
2009-01-01
Concentrated animal feeding operations (CAFO) and fertilizer application to row crops may contribute to poor water quality in surface waters. To test this hypothesis, we evaluated nutrient concentrations and fluxes in four Eastern Iowa watersheds sampled between 1996-2004. We found that these watersheds contribute nearly 10% of annual nitrate flux entering the Gulf of Mexico, while representing only 1.5% of the contributing drainage basin. Mass budget analysis shows stream flow to be a major loss of nitrogen (18% of total N output), second only to crop harvest (63%). The major watershed inputs of nitrogen include applied fertilizer for corn (54% of total N input) and nitrogen fixation by soybeans (26%). Despite the relatively small input from animal manure (~5%), the results of spatial analysis indicate that row crop and CAFO densities are significantly and independently correlated to higher nitrate concentration in streams. Pearson correlation coefficients of 0.59 and 0.89 were found between nitrate concentration and row crop and CAFO density, respectively. Multiple linear regression analysis produced a correlation for nitrate concentration with an R2 value of 85%. High spatial density of row crops and CAFOs are linked to the highest river nitrate concentrations (up to 15 mg/l normalized over five years). PMID:16749677
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taylor-Pashow, Kathryn M.; Nash, Charles A.; Crawford, Charles L.
2014-01-21
The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrificationmore » mission duration and quantity of glass waste. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task seeks to examine the potential treatment of this stream to remove radionuclides and subsequently disposition the decontaminated stream elsewhere, such as the Effluent Treatment Facility (ETF), for example. The treatment process envisioned is very similar to that used for the Actinide Removal Process (ARP) that has been operating for years at the Savannah River Site (SRS), and focuses on using mature radionuclide removal technologies that are also compatible with longterm tank storage and immobilization methods. For this new application, testing is needed to demonstrate acceptable treatment sorbents and precipitating agents and measure decontamination factors for additional radionuclides in this unique waste stream. The origin of this LAW Off-Gas Condensate stream will be the liquids from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW melter off-gas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover. The soluble components are expected to be mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet and will not be available until the WTP begins operation, but a simulant has been produced based on models, calculations, and comparison with pilot-scale tests. One of the radionuclides that is volatile and expected to be in high concentration in this LAW Off-Gas Condensate stream is Technetium-99 ( 99Tc). Technetium will not be removed from the aqueous waste in the Hanford WTP, and will primarily end up immobilized in the LAW glass by repeated recycle of the off-gas condensate into the LAW melter. Other radionuclides that are also expected to be in appreciable concentration in the LAW Off-Gas Condensate are 129I, 90Sr, 137Cs, and {sup 241}Am. This report discusses results of preliminary radionuclide decontamination testing of the simulant. Testing examined use of Monosodium Titanate (MST) to remove 90Sr and actinides, inorganic reducing agents for 99Tc, and zeolites for 137Cs. Test results indicate that excellent removal of 99Tc was achieved using Sn(II)Cl 2 as a reductant, coupled with sorption onto hydroxyapatite, even in the presence of air and at room temperature. This process was very effective at neutral pH, with a Decontamination Factor (DF) >577 in two hours. It was less effective at alkaline pH. Conversely, removal of the cesium was more effective at alkaline pH, with a DF of 17.9. As anticipated, ammonium ion probably interfered with the Ionsiv®a IE-95 zeolite uptake of 137Cs. Although this DF of 137Cs was moderate, additional testing is expected to identify more effective conditions. Similarly, Monosodium Titanate (MST) was more effective at alkaline pH at removing Sr, Pu, and U, with a DF of 319, 11.6, and 10.5, respectively, within 24 hours. Actually, the Ionsiv® IE-95, which was targeting removal of Cs, was also moderately effective for Sr, and highly effective for Pu and U at alkaline pH. The only deleterious effect observed was that the chromium co-precipitates with the {sup 99}Tc during the SnCl 2 reduction. This effect was anticipated, and would have to be considered when managing disposition paths of this stream. Results of this separation testing indicate that sorption/precipitation was a viable concept and has the potential to decontaminate the stream. All radionuclides were at least partially removed by one or more of the materials tested. Based on the results, a possible treatment scenario could involve the use of a reductive precipitation agent (SnCl 2) and sorbent at neutral pH to remove the Tc, followed by pH adjustment and the addition of zeolite (Ionsiv® IE-95) to remove the Cs, Sr, and actinides. Addition of MST to remove Sr and actinides may not be needed. Since this was an initial phase of testing, additional tasks to improve separation methods were expected to be identified. Primarily, further testing is needed to identify the conditions for the decontamination process. Once these conditions are established, follow-on tasks likely include evaluation and testing of applicable solid-liquid separation technologies, slurry rheology measurements, composition variability testing and evaluations, corrosion and erosion testing, slurry storage and immobilization investigations, and decontaminated LAW Off-Gas Condensate evaporation and solidification.« less
Hydrothermal treatment of hazardous energetic materials waste
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brill, T.B.; Schoppelrei, J.W.; Maiella, P.G.
1995-12-31
Destruction of energetic materials by hydrothermal methods presents a potential for strongly exothermic oxidation-reduction reactions, which, if localized at a site in the reactor, create {open_quotes}hot spots{close_quotes}. To investigate highly exothermic hydrothermal reactions, real-time spectroscopic measurements in the stream by infrared and Raman spectroscopy offer opportunities. Flow reactor-spectroscopy cells were developed for such studies, focusing on approximately oxygen-balanced nitrate salts for which highly exothermic reactions can occur. In addition, the kinetics of formation of later stage products were studied because these products are likely to be released to the environment and to be regulated. An experiment was designed to simulatemore » the occurence of a phase separation in a reactor followed by rapid exothermic reaction. By varying the pressure, water content, and hydrogen content in the reaction volume of the cell, the freeze out temperatures required to set the carbon monoxide/carbon dioxide ratio were determined to be 1300 to 1470 K. Such high temperatures suggest that localized hot spots can exist which greatly exceed the overall set temperature of the reactor. This scenario can occur if a phase separation occurs to isolate ethylenediammonium dinitrate in quantities as small as tenths of milligrams. Studies of the oxidation-reduction reactions of nitrate ion with the counter ion show that the oxidizing power of the nitrate ion is realized provided a readily oxidizable cation such as hydroxylammonium is present. When the cation has a low reactivity, such as quanidinium, a much higher reaction temperature is required before the nitrate ion reacts. At this temperature, the cation may have already begun to decompose by a hydrothermal route.« less
GIS Spatial Analysis of Water Quality at Courtland Creek in Oakland, California
NASA Astrophysics Data System (ADS)
Matias, F.; Perez, L.; Martinez, E.; Rivera Soto, E.; McDonald, K.; Garcia, D.; Ruiz, I.
2015-12-01
Courtland Creek is a channelized stream that traverses residential and industrial sections of East Oakland, California. Segments of the creek are exposed on the surface and have been designated as City of Oakland park land. Since 2012, the quality of creek waters has been monitored through measurement and analysis of nutrient and other possible contaminant levels in samples collected in these exposed segments. Throughout the three-year period during which monitoring efforts have been undertaken, high concentration levels of nitrate have been observed. The primary aim of our research is to gain an overall indication of creek health in relation to its surrounding environment through the use of Geographic Information Systems (GIS) analysis of nutrient concentrations at the four sites. Investigating the relationship between Courtland Creek and the environmental factors influencing its health will enable us to develop a better sense of the actions that can be taken by the City of Oakland to create sustainable park land and healthy communities. During the summer of 2015, our group continued to monitor levels of ammonia, phosphate and nitrate at four different sites along the creek, and benthic macroinvertebrates were sampled at one of these sites. Preliminary analysis of benthic macroinvertebrate data indicates that Courtland Creek is in poor health ecologically. Nitrate concentration levels measured during the study period were lower than those detected in previous years but still indicate inputs other than those associated with natural processes. The high nitrate concentration levels may be the result of human and animal waste pollution, as supported by data obtained during a recent Environmental Protection Agency (EPA) - led E. coli survey that included the watershed within which Courtland Creek is situated.
Modeling the economics of landfilling organic processing waste streams
NASA Astrophysics Data System (ADS)
Rosentrater, Kurt A.
2005-11-01
As manufacturing industries become more cognizant of the ecological effects that their firms have on the surrounding environment, their waste streams are increasingly becoming viewed not only as materials in need of disposal, but also as resources that can be reused, recycled, or reprocessed into valuable products. Within the food processing sector are many examples of various liquid, sludge, and solid biological and organic waste streams that require remediation. Alternative disposal methods for food and other bio-organic manufacturing waste streams are increasingly being investigated. Direct shipping, blending, extrusion, pelleting, and drying are commonly used to produce finished human food, animal feed, industrial products, and components ready for further manufacture. Landfilling, the traditional approach to waste remediation, however, should not be dismissed entirely. It does provide a baseline to which all other recycling and reprocessing options should be compared. This paper discusses the implementation of a computer model designed to examine the economics of landfilling bio-organic processing waste streams. Not only are these results applicable to food processing operations, but any industrial or manufacturing firm would benefit from examining the trends discussed here.
Process for the displacement of cyanide ions from metal-cyanide complexes
Smith, Barbara F.; Robinson, Thomas W.
1997-01-01
The present invention relates to water-soluble polymers and the use of such water-soluble polymers in a process for the displacement of the cyanide ions from the metal ions within metal-cyanide complexes. The process waste streams can include metal-cyanide containing electroplating waste streams, mining leach waste streams, mineral processing waste streams, and related metal-cyanide containing waste streams. The metal ions of interest are metals that give very strong complexes with cyanide, mostly iron, nickel, and copper. The physical separation of the water-soluble polymer-metal complex from the cyanide ions can be accomplished through the use of ultrafiltration. Once the metal-cyanide complex is disrupted, the freed cyanide ions can be recovered for reuse or destroyed using available oxidative processes rendering the cyanide nonhazardous. The metal ions are released from the polymer, using dilute acid, metal ion oxidation state adjustment, or competing chelating agents, and collected and recovered or disposed of by appropriate waste management techniques. The water-soluble polymer can then be recycled. Preferred water-soluble polymers include polyethyleneimine and polyethyleneimine having a catechol or hydroxamate group.
Modeling biotic uptake by periphyton and transient hyporrheic storage of nitrate in a natural stream
Kim, Brian K.A.; Jackman, Alan P.; Triska, Frank J.
1992-01-01
To a convection-dispersion hydrologic transport model we coupled a transient storage submodel (Bencala, 1984) and a biotic uptake submodel based on Michaelis-Menten kinetics (Kim et al., 1990). Our purpose was threefold: (1) to simulate nitrate retention in response to change in load in a third-order stream, (2) to differentiate biotic versus hydrologie factors in nitrate retention, and (3) to produce a research tool whose properties are consistent with laboratory and field observations. Hydrodynamic parameters were fitted from chloride concentration during a 20-day chloride-nitrate coinjection (Bencala, 1984), and biotic uptake kinetics were based on flume studies by Kim et al. (1990) and Triska et al. (1983). Nitrate concentration from the 20-day coinjection experiment served as a base for model validation. The complete transport retention model reasonably predicted the observed nitrate concentration. However, simulations which lacked either the transient storage submodel or the biotic uptake submodel poorly predicted the observed nitrate concentration. Model simulations indicated that transient storage in channel and hyporrheic interstices dominated nitrate retention within the first 24 hours, whereas biotic uptake dominated thereafter. A sawtooth function for Vmax ranging from 0.10 to 0.17 μg NO3-N s−1 gAFDM−1 (grams ash free dry mass) slightly underpredicted nitrate retention in simulations of 2–7 days. This result was reasonable since uptake by other nitrate-demanding processes were not included. The model demonstrated how ecosystem retention is an interaction between physical and biotic processes and supports the validity of coupling separate hydrodynamic and reactive submodels to established solute transport models in biological studies of fluvial ecosystems.
Rodriguez, Jose M.
2006-01-01
A ground-water quality study to define the potential sources and concentration of nitrate in the Rio Nigua de Salinas alluvial fan aquifer was conducted between January 2002 and March 2003. The study area covers about 3,600 hectares of the coastal plain within the municipality of Salinas in southern Puerto Rico, extending from the foothills to the Caribbean Sea. Agriculture is the principal land use and includes cultivation of diverse crops, turf grass, bioengineered crops for seed production, and commercial poultry farms. Ground-water withdrawal in the alluvial fan was estimated to be about 43,500 cubic meters per day, of which 49 percent was withdrawn for agriculture, 42 percent for public supply, and 9 percent for industrial use. Ground-water flow in the study area was primarily to the south and toward a cone of depression within the south-central part of the alluvial fan. The presence of that cone of depression and a smaller one located in the northeastern quadrant of the study area may contribute to the increase in nitrate concentration within a total area of about 545 hectares by 'recycling' ground water used for irrigation of cultivated lands. In an area that covers about 405 hectares near the center of the Salinas alluvial fan, nitrate concentrations increased from 0.9 to 6.7 milligrams per liter as nitrogen in 1986 to 8 to 12 milligrams per liter as nitrogen in 2002. Principal sources of nitrate in the study area are fertilizers (used in the cultivated farmlands) and poultry farm wastes. The highest nitrogen concentrations were found at poultry farms in the foothills area. In the area of disposed poultry farm wastes, nitrate concentrations in ground water ranged from 25 to 77 milligrams per liter as nitrogen. Analyses for the stable isotope ratios of nitrogen-15/nitrogen-14 in nitrate were used to distinguish the source of nitrate in the coastal plain alluvial fan aquifer. Potential nitrate loads from areas under cultivation were estimated for the principal crops in the area. The load estimates ranged from 18 kilograms per hectare per year as nitrogen for sorghum crops to 430 kilograms per hectare per year as nitrogen for turf-grass farms. Potential nitrate load from poultry farm wastes and from communities with septic tanks were estimated at about 580 and 47 kilograms per hectare per year as nitrogen, respectively. Results obtained from the analyses of the stable isotope ratios of nitrogen-15/nitrogen-14 in nitrate samples indicated that the high nitrate concentrations are from poultry wastes near the foothills, whereas artificial fertilizers were estimated to contribute between 39 to 97 percent of the total nitrate in the central part of the alluvial fan.
Potential metal recovery from waste streams
Smith, Kathleen S.; Hageman, Philip L.; Plumlee, Geoffrey S.; Budahn, James R.; Bleiwas, Donald I.
2015-01-01
‘Waste stream’ is a general term that describes the total flow of waste from homes, businesses, industrial facilities, and institutions that are recycled, burned or isolated from the environment in landfills or other types of storage, or dissipated into the environment. The recovery and reuse of chemical elements from waste streams have the potential to decrease U.S. reliance on primary resources and imports, and to lessen unwanted dispersion of some potentially harmful elements into the environment. Additional benefits might include reducing disposal or treatment costs and decreasing the risk of future environmental liabilities for waste generators. Elemental chemistry and mineralogical residences of the elements are poorly documented for many types of waste streams.
Browne, James D; Allen, Eoin; Murphy, Jerry D
2013-01-01
This paper examines the biomethane potential from organic waste for a proposed community scale anaerobic digester in a rural town. The biomethane potential test is used to assess the suitability of waste streams for biomethane production and to examine the variation in biomethane potential between waste sub-streams. A methodology for accurately estimating the biomethane potential from multiple heterogeneous organic waste substrates is sought. Five main waste streams were identified as possible substrates for biogas production, namely Abattoir waste (consisting of paunch and de-watered activated sludge); cheese factory effluent; commercial and domestic food waste; pig slurry and waste water treatment sludge. The biomethane potential of these waste streams ranged from as low as 99 L CH4 kg VS(-1) for pig slurry to as high as 787 L CH4 kg VS(-1) for dissolved air floatation (DAF) sludge from a cheese effluent treatment plant. The kinetic behaviour of the biomethane production in the batch test is also examined. The objective of the paper is to suggest an optimum substrate mix in terms of biomethane yield per unit substrate for the proposed anaerobic digester. This should maximize the yield of biomethane per capital investment. Food waste displayed the highest biomethane yield (128 m(n)(3) t(-1)) followed by cheese waste (38 m(n)(3) t(-1)) and abattoir waste (36 m(n)(3) t(-1)). It was suggested that waste water sludge (16 m(n)(3) t(-1)) and pig slurry (4 m(n)(3) t(-1)) should not be digested. However, the biomethane potential test does not give information on the continuous operation of an anaerobic digester.
Kent, Robert; Belitz, Kenneth
2004-01-01
Concentrations of total dissolved solids (TDS) and nutrients in selected Santa Ana Basin streams were examined as a function of water source. The principal water sources are mountain runoff, wastewater, urban runoff, and stormflow. Rising ground water also enters basin streams in some reaches. Data were collected from October 1998 to September 2001 from 6 fixed sites (including a mountain site), 6 additional mountain sites (including an alpine indicator site), and more than 20 synoptic sites. The fixed mountain site on the Santa Ana River near Mentone appears to be a good representative of reference conditions for water entering the basin. TDS can be related to water source. The median TDS concentration in base-flow samples from mountain sites was 200 mg/L (milligrams per liter). Base-flow TDS concentrations from sites on the valley floor typically ranged from 400 to 600 mg/L; base flow to most of these sites is predominantly treated wastewater, with minor contributions of rising ground water and urban runoff. Sparse data suggest that TDS concentrations in urban runoff are about 300 mg/L. TDS concentrations appear to increase on a downstream gradient along the main stem of the Santa Ana River, regardless of source inputs. The major-ion compositions observed in samples from the different sites can be related to water source, as well as to in-stream processes in the basin. Water compositions from mountain sites are categorized into two groups: one group had a composition close to that of the alpine indicator site high in the watershed, and another group had ionic characteristics closer to those in tributaries on the valley floor. The water composition at Warm Creek, a tributary urban indicator site, was highly variable but approximately intermediate to the compositions of the upgradient mountain sites. Water compositions at the Prado Dam and Imperial Highway sites, located 11 miles apart on the Santa Ana River, were similar to one another and appeared to be a mixture of the waters of the upstream sites, Santa Ana River at MWD Crossing, Cucamonga Creek, and Warm Creek. Rainfall usually dilutes stream TDS concentrations. The median TDS concentration in all storm-event discrete samples was 260 mg/L. The median flow-weighted average TDS concentration for stormflow, based on continuous measurement of specific conductance and hydrograph separation of the continuous discharge record, was 190 mg/L. However, stormflow TDS concentrations were variable, and depended on whether the storm was associated with a relatively small or large rainfall event. TDS concentrations in stormflow associated with relatively small events ranged from about 50 to 600 mg/L with a median of 220 mg/L, whereas concentrations in stormflow associated with relatively large events ranged from about 40 to 300 mg/L with a median of 100 mg/L. From the perspective of water managers, the nutrient species of highest concern in Santa Ana Basin streams is nitrate. Most mountain streams had median base-flow concentrations of nitrate below 0.3 mg/L as nitrogen. Nitrate concentrations in both urban runoff and stormflow were near 1 mg/L, which is close to the level found in rainfall for the region. In fact, results from this study suggest that much of the nitrate load in urban storm runoff comes from rainwater. Nitrate concentrations in the Santa Ana River and its major tributaries are highest downstream from wastewater inputs, where median base-flow concentrations of nitrite+nitrate ranged from about 5 to 7 mg/L. About 4 percent of samples collected from sites receiving treated wastewater had nitrate concentrations greater than 10 mg/L. Rising ground water also appears to have high nitrate concentrations (greater than 10 mg/L) in some reaches of the river. Concentrations of other nitrogen species were much lower than nitrate concentrations in base-flow samples. However, storm events increased concentrations and the proportion of organic nitro
Synchronicity of long-term nitrate patterns in forested catchments across the northeastern U.S.
Nitrogen movement through minimally-disturbed catchments can be affected by a variety of biogeochemical processes, climatic effects, hydrology and in-stream or in-lake processes. These combine to create dizzying complexity in long-term and seasonal nitrate patterns, with adjacen...
Negative ion spectrometry for detecting nitrated explosives
NASA Technical Reports Server (NTRS)
Boettger, H. G.; Yinon, J.
1975-01-01
Ionization procedure is modified to produce mainly negative ions by electron capture. Peaks of negative ions are monitored conventionally. Nitrated organic materials could be identified directly from sample sniff inlet stream by suitably modified mass spectrometer because of unique electronegativity which nitro group imparts to organic material.
Zamora, Celia; Dahlgren, Randy A.; Kratzer, Charles R.; Downing, Bryan D.; Russell, Ann D.; Dileanis, Peter D.; Bergamaschi, Brian A.; Phillips, Steven P.
2013-01-01
The influence of groundwater on surface-water quality in the San Joaquin River, California, was examined for a 59-mile reach from the confluence with Salt Slough to Vernalis. The primary objective of this study was to quantify the rate of groundwater discharged to the lower San Joaquin River and the contribution of nitrate and dissolved organic carbon concentrations to the river. Multiple lines of evidence from four independent approaches were used to characterize groundwater contributions of nitrogen and dissolved organic carbon. Monitoring wells (in-stream and bank wells), streambed synoptic surveys (stream water and shallow groundwater), longitudinal profile surveys by boat (continuous water-quality parameters in the stream), and modeling (MODFLOW and VS2DH) provided a combination of temporal, spatial, quantitative, and qualitative evidence of groundwater contributions to the river and the associated quality. Monitoring wells in nested clusters in the streambed (in-stream wells) and on both banks (bank wells) along the river were monitored monthly from September 2006 to January 2009. Nitrate concentrations in the bank wells ranged from less than detection—that is, less than 0.01 milligrams per liter (mg/L) as nitrogen (N)—to approximately 13 mg/L as N. Nitrate was not detected at 17 of 26 monitoring wells during the study period. Dissolved organic carbon concentrations among monitoring wells were highly variable, but they generally ranged from 1 to 4 mg/L. In a previous study, 14 bank wells were sampled once in 1988 following their original installation. With few exceptions, specific conductivity and nitrate concentrations measured in this study were virtually identical to those measured 20 years ago. Streambed synoptic measurements were made by using a temporarily installed drive-point piezometer at 113 distinct transects across the stream during 4 sampling events. Nitrate concentrations exceeded the detection limit of 0.01 mg/L as N in 5 percent of groundwater samples collected from the in-stream wells as part of the synoptic surveys. Only 7 of the 113 cross-sectional transects had nitrate concentrations greater than 1 mg/L as N. In contrast, surface waters in the San Joaquin River tended to have nitrate concentrations in the 1–3 mg/L as N range. A zone of lower oxygen (less than 2 mg/L) in the streambed could limit nitrate contributions from regional groundwater flow because nitrate can be converted to nitrogen gas within this zone. Appreciable concentrations of ammonium (average concentration was 1.92 mg/L as N, and 95th percentile was 10.34 mg/L as N) in the shallow groundwater, believed to originate from anoxic mineralization of streambed sediments, could contribute nitrogen to the overlying stream as nitrate following in-stream nitrification, however. Dissolved organic carbon concentrations were highly variable in the shallow groundwater below the river (1 to 6 ft below streambed) and generally ranged between 1 and 5 mg/L, but had maximum concentrations in the 15–25 mg/L range. The longitudinal profile surveys were not particularly useful in identifying groundwater discharge areas. However, the longitudinal approach described in this report was useful as a baseline survey of measured water-quality parameters and for identifying tributary inflows that affect surface-water concentrations of nitrate. Results of the calibrated MODFLOW model indicated that the simulated groundwater discharge rate was approximately 1.0 cubic foot per second per mile (cfs/mi), and the predominant horizontal groundwater flow direction between the deep bank wells was westward beneath the river. The modeled (VS2DH) flux values (river gain versus river loss) were calculated for the irrigation and non-irrigation season, and these fluxes were an order of magnitude less than those from MODFLOW. During the irrigation season, the average river gain was 0.11 cfs/mi, and the average river loss was −0.05 cfs/mi. During the non-irrigation season, the average river gain was 0.10 cfs/mi, and the average river loss was -0.08 cfs/mi. Information on groundwater interactions and water quality collected for this study was used to estimate loads of nitrate and dissolved organic carbon from the groundwater to the San Joaquin River. Estimated loads of dissolved inorganic nitrogen and dissolved organic carbon were calculated by using concentrations measured during four streambed synoptic surveys and the estimated groundwater discharge rate to the San Joaquin River from MODFLOW of 1 cfs/mi. The estimated groundwater loads to the San Joaquin River for dissolved inorganic nitrogen and dissolved organic carbon were 300 and 350 kilograms per day, respectively. These loads represent 9 and 7 percent, respectively, of the estimated instantaneous surface-water loads for dissolved inorganic nitrogen and dissolved organic carbon at the most downstream site, Vernalis, measured during the four streambed synoptic surveys.
Whitehead, P G; Wilby, R L; Butterfield, D; Wade, A J
2006-07-15
The impacts of climate change on nitrogen (N) in a lowland chalk stream are investigated using a dynamic modelling approach. The INCA-N model is used to simulate transient daily hydrology and water quality in the River Kennet using temperature and precipitation scenarios downscaled from the General Circulation Model (GCM) output for the period 1961-2100. The three GCMs (CGCM2, CSIRO and HadCM3) yield very different river flow regimes with the latter projecting significant periods of drought in the second half of the 21st century. Stream-water N concentrations increase over time as higher temperatures enhance N release from the soil, and lower river flows reduce the dilution capacity of the river. Particular problems are shown to occur following severe droughts when N mineralization is high and the subsequent breaking of the drought releases high nitrate loads into the river system. Possible strategies for reducing climate-driven N loads are explored using INCA-N. The measures include land use change or fertiliser reduction, reduction in atmospheric nitrate and ammonium deposition, and the introduction of water meadows or connected wetlands adjacent to the river. The most effective strategy is to change land use or reduce fertiliser use, followed by water meadow creation, and atmospheric pollution controls. Finally, a combined approach involving all three strategies is investigated and shown to reduce in-stream nitrate concentrations to those pre-1950s even under climate change.
WOOD PRODUCTS IN THE WASTE STREAM: CHARACTERIZATION AND COMBUSTION EMISSIONS - VOLUME 2. APPENDICES
The report gives results of a study of technical, public policy, and regulatory issues that affect the processing and combustion of waste wood for fuel. (NOTE: Waste wood is wood that is separated from a solid-waste stream, processed into a uniform-sized product, and reused for o...
The report gives results of a study of technical, public policy, and regulatory issues that affect the processing and combustion of waste wood for fuel. (NOTE: Waste wood is wood that is separated from a solid-waste stream, processed into a uniform-sized product, and reused for o...
Frans, Lonna; Paulson, Anthony; Richerson, Phil; Striz, Elise; Black, Curt
2009-01-01
Water samples from wells were collected beneath and downgradient of two food-processing wastewater-application sites near Umatilla, Oregon. These samples were analyzed for nitrate stable isotopes, nutrients, major ions, and age-dating constituents to determine if nitrate-stable isotopes can be used to differentiate food-processing waste from other potential sources of nitrate. Major-ion data from each site were used to determine which samples were associated with the recharge of the food-processing wastewater. End-member mixing analysis was used to determine the relative amounts of each identified end member within the samples collected from the Terrace Farm site. The delta nitrogen-15 (delta 15N) of nitrate generally ranged between +2 and +9 parts per thousand and the delta oxygen-18 (delta 18O) of nitrate generally ranged between -2 and -7 parts per thousand. None of the samples that were determined to be associated with the wastewater were different from the samples that were not affected by the wastewater. The nitrate isotope values measured in this study are also characteristic of ammonium fertilizer, animal and human waste, and soil nitrate; therefore, it was not possible to differentiate between food-processing wastewater and the other nitrate sources. Values of delta 15N and delta 18O of nitrate provided no more information about the sources of nitrate in the Umatilla River basin than did a hydrologic and geochemical understanding of the ground-water system derived from interpreting water-level and major-ion chemistry data.
Assessment of Options for the Treatment of Nitrate Salt Wastes at Los Alamos National Laboratory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robinson, Bruce Alan; Funk, David John; Stevens, Patrice Ann
2016-03-17
This paper summarizes the methodology used to evaluate options for treatment of the remediated nitrate salt waste containers at Los Alamos National Laboratory. The method selected must enable treatment of the waste drums, which consist of a mixture of complex nitrate salts (oxidizer) improperly mixed with sWheat Scoop®1, an organic kitty litter and absorbent (fuel), in a manner that renders the waste safe, meets the specifications of waste acceptance criteria, and is suitable for transport and final disposal in the Waste Isolation Pilot Plant located in Carlsbad, New Mexico. A Core Remediation Team was responsible for comprehensively reviewing the options,more » ensuring a robust, defensible treatment recommendation. The evaluation process consisted of two steps. First, a prescreening process was conducted to cull the list on the basis for a decision of feasibility of certain potential options with respect to the criteria. Then, the remaining potential options were evaluated and ranked against each of the criteria in a consistent methodology. Numerical scores were established by consensus of the review team. Finally, recommendations were developed based on current information and understanding of the scientific, technical, and regulatory situation. A discussion of the preferred options and documentation of the process used to reach the recommended treatment options are presented.« less
Identification of nitrate sources and discharge-depending nitrate dynamics in a mesoscale catchment
NASA Astrophysics Data System (ADS)
Mueller, Christin; Strachauer, Ulrike; Brauns, Mario; Musolff, Andreas; Kunz, Julia Vanessa; Brase, Lisa; Tarasova, Larisa; Merz, Ralf; Knöller, Kay
2017-04-01
During the last decades, nitrate concentrations in surface and groundwater have increased due to land use change and accompanying application of fertilizer in agriculture as well as increased atmospheric deposition. To mitigate nutrient impacts on downstream aquatic ecosystems, it is important to quantify potential nitrate sources, instream nitrate processing and its controls in a river system. The objective of this project is to characterize and quantify (regional) scale dynamics and trends in water and nitrogen fluxes of the entire Holtemme river catchment in central Germany making use of isotopic fingerprinting methods. Here we compare two key date sampling campaigns in 2014 and 2015, with spatially highly resolved measurements of discharge at 23 sampling locations including 11 major tributaries and 12 locations at the main river. Additionally, we have data from continuous runoff measurements at 10 locations operated by the local water authorities. Two waste water treatment plants contribute nitrogen to the Holtemme stream. This contribution impacts nitrate loads and nitrate isotopic signatures depending on the prevailing hydrological conditions. Nitrogen isotopic signatures in the catchment are mainly controlled by different sources (nitrified soil nitrogen in the headwater and manure/ effluents from WWTPs in the lowlands) and increase with raising nitrate concentrations along the main river. Nitrate loads at the outlet of the catchment are extremely different between both sampling campaigns (2014: NO3- = 97 t a-1, 2015: NO3- = 5 t a-1) which is associated with various runoff (2014: 0.8 m3 s-1, 2015: 0.2 m3 s-1). In 2015, the inflow from WWTP's raises the NO3- loads and enriches δ18O-NO3 values. Generally, oxygen isotope signatures from nitrate are more variable and are controlled by biogeochemical processes in concert with the oxygen isotopic composition of the ambient water. Elevated δ18O-NO3 in 2015 are most likely due to higher temperatures and lower discharge resulting in a higher impact of evaporation on water isotopes and a higher/different level of biological activity (esp. in the WWTP). Enriched isotope values for nitrogen and oxygen are not indicative of a significant impact of bacterial denitrification, because they are accompanied by increased nitrate concentrations (1 to 16 mg L-1). Based on the presented study, 50 % of the nitrate export from the Holtemme river catchment can be attributed to WWTP effluent. The remaining amount is related to agricultural land use. Consequently, nitrate load reduction in the river system cannot rely on internal processing but needs to be regulated by preventive measures especially by an improved wastewater treatment and land use management.
ASSESSING THE IMPACT OF LANDUSE/LANDCOVER ON STREAM CHEMISTRY IN MARYLAND
Spatial and statistical analyses were conducted to investigate the relationships between stream chemistry (nitrate, sulfate, dissolved organic carbon, etc.), habitat and satellite-derived landuse maps for the state of Maryland. Hydrologic Unit Code (HUC) watershed boundaries (8-...
Mixed waste management options
DOE Office of Scientific and Technical Information (OSTI.GOV)
Owens, C.B.; Kirner, N.P.
1991-12-31
Disposal fees for mixed waste at proposed commercial disposal sites have been estimated to be $15,000 to $40,000 per cubit foot. If such high disposal fees are imposed, generators may be willing to apply extraordinary treatment or regulatory approaches to properly dispose of their mixed waste. This paper explores the feasibility of several waste management scenarios and attempts to answer the question: Can mixed waste be managed out of existence? Existing data on commercially generated mixed waste streams are used to identify the realm of mixed waste known to be generated. Each waste stream is evaluated from both a regulatorymore » and technical perspective in order to convert the waste into a strictly low-level radioactive or a hazardous waste. Alternative regulatory approaches evaluated in this paper include a delisting petition, no migration petition, and a treatability variance. For each waste stream, potentially available treatment options are identified that could lead to these variances. Waste minimization methodology and storage for decay are also considered. Economic feasibility of each option is discussed broadly.« less
Xu, Yaxian; Chen, Nan; Feng, Chuanping; Hao, Chunbo; Peng, Tong
2016-12-01
Eggshell is considered to be a waste and a significant quantity of eggshell waste is generated from food processing, baking and hatching industries. In this study, the effect of different sulfur/eggshell (w/w) ratios and temperatures was investigated to evaluate the feasibility of the sulfur-based autotrophic denitrification with eggshell (SADE) process for nitrate removal. The results showed eggshell can maintain a neutral condition in a range of pH 7.05-7.74 in the SADE process, and remove 97% of nitrate in synthetic groundwater. Compared with oyster shell and limestone, eggshell was found to be a desirable alkaline material for sulfur-based autotrophic denitrification (SAD) with no nitrite accumulation and insignificant sulfate production. Denitrification reaction was found to follow the first-order kinetic models (R(2) > .9) having nitrate removal rate constants of 0.85 and 0.93 d(-1) for raw eggshell and boiled eggshell, respectively. Sulfur/eggshell ratio of 2:3 provided the best efficiency on nitrate removal. Nitrate was removed completely by the SADE process at a low temperature of 15°C. Eggshell could be used for the SAD process due to its good effect for nitrate removal from groundwater.
Shanley, J.B.; Kendall, C.; Albert, M.R.; Hardy, J.P.
1995-01-01
The chemical, isotopic, and morphologic evolution of a layered snowpack was investigated during the winter of 1993-94 at Sleepers River Research Watershed in Danville, Vermont. The snowpack was monitored at two small basins: a forested basin at 525 m elevation, and an agricultural basin at 292 m elevation. At each site, the snowpack morphology was characterized and individual layers were sampled seven times during the season. Nitrate and 8d18O profiles in the snowpack remained relatively stable until peak accumulation in mid-March, except near the snow surface, where rain-on-snow events caused water and nitrate movement down to impeding ice layers. Subsequently, water and nitrate moved more readily through the ripening snowpack. As the snowpack evolved, combined processes of preferential ion elution, isotopic fractionation, and infiltration of isotopically heavy rainfall caused the pack to become depleted in solutes and isotopically enriched. The release of nitrate and isotopically depleted water was reflected in patterns of nitrate concentrations and ??18O of meltwater and stream water. Results supported data from the previous year which suggested that streamflow in the forested basin during snowmelt was dominated by groundwater discharge.
Potential Impacts of Organic Wastes on Small Stream Water Quality
NASA Astrophysics Data System (ADS)
Kaushal, S. S.; Groffman, P. M.; Findlay, S. E.; Fischer, D. T.; Burke, R. A.; Molinero, J.
2005-05-01
We monitored concentrations of dissolved organic carbon (DOC), dissolved oxygen (DO) and other parameters in 17 small streams of the South Fork Broad River (SFBR) watershed on a monthly basis for 15 months. The subwatersheds were chosen to reflect a range of land uses including forested, pasture, mixed, and developed. The SFBR watershed is heavily impacted by organic wastes, primarily from its large poultry industry, but also from its rapidly growing human population. The poultry litter is primarily disposed of by application to pastures. Our monthly monitoring results showed a strong inverse relationship between mean DOC and mean DO and suggested that concentrations of total nitrogen (TN), DOC, and the trace gases nitrous oxide, methane and carbon dioxide are impacted by organic wastes and/or nutrients from animal manure applied to the land and/or human wastes from wastewater treatment plants or septic tanks in these watersheds. Here we estimate the organic waste loads of these watersheds and evaluate the impact of organic wastes on stream DOC and alkalinity concentrations, electrical conductivity, sediment potential denitrification rate and plant stable nitrogen isotope ratios. All of these water quality parameters are significantly correlated with watershed waste loading. DOC is most strongly correlated with total watershed waste loading whereas conductivity, alkalinity, potential denitrification rate and plant stable nitrogen isotope ratio are most strongly correlated with watershed human waste loading. These results suggest that more direct inputs (e.g., wastewater treatment plant effluents, near-stream septic tanks) have a greater relative impact on stream water quality than more dispersed inputs (land applied poultry litter, septic tanks far from streams) in the SFBR watershed. Conductivity, which is generally elevated in organic wastes, is also significantly correlated with total watershed waste loading suggesting it may be a useful indicator of overall watershed waste loading. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy.
NASA Astrophysics Data System (ADS)
Doležal, František; Kvítek, Tomáš
The hydrogeology, runoff generation and water quality generation in old peneplains of Central Europe built by acid crystalline rocks (such as the Bohemo-Moravian Highland) are described and interpreted in terms of a three-zone concept. The recharge zones are located on flat tops of hills and their soils are mostly permeable. It is mainly through them that the shallow groundwater-bearing formations are loaded with nitrate. The groundwater exfiltrates on the lower parts of slopes (in the so-called transient zone) and in narrow valleys (in the discharge zone), creating dispersed springs and waterlogged areas. In addition, the rapid and shallow flow of perched groundwater down the slope, which takes place during wet periods in the recharge zone and, mainly, in the transient zone, leaches the nitrate from the soil directly to the stream, without necessarily being in contact with the permanent groundwater table of the recharge and the transient zones. Discharge and water quality measurements in the Kopaninský tok experimental catchment (6.7 km 2) were analysed, using a combination of two runoff separation techniques (a digital filter and a simple conceptual model GROUND). Three runoff components were distinguished (direct runoff, interflow and baseflow). There is a weak but significant positive correlation between the stream nitrate concentration on the one hand and either the interflow or the baseflow on the other hand. There is also a weak but significant negative correlation between the stream nitrate concentration on the one hand and either the ratio of direct runoff to total stream flow or the logarithm of this ratio on the other hand, provided that the cases of zero direct runoff are disregarded. A simple mixing model was used to estimate the characteristic nitrate concentrations of individual runoff components. The interflow has the highest characteristic nitrate concentration and is probably the main stream water polluter with nitrate. The baseflow is identified as the likely second main polluter. The differences in water quality between a drainage outlet and a forest spring indicate the importance of a proper nitrogen management in the recharge zones. It is also concluded that the tile drainage and tillage of formerly waterlogged sites, mainly located in transient zones, reduce the opportunity for denitrification of both baseflow and interflow. The ploughed lands in the recharge zones represent an established basis for local agriculture and cannot be easily set aside. Many such lands have been declared as vulnerable to nitrate pollution in order to protect waters against impacts of risky agricultural practices. It is proposed that some waterlogged and drained sites in the transient and discharge zones are set aside rather than the flat ploughed lands on the hill tops. To increase the denitrification, tile drainage runoff from the transient and the discharge zones should be retarded.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-09
..., nitrogenous: Double salts and mixtures of calcium nitrate and ammonium nitrate.'' This document invites... Marking Branch, Regulations and Rulings, Office of International Trade at (202) 325-0036. SUPPLEMENTARY... calcium nitrate double salt that is primarily used as a fertilizer but is also used for waste water...
Siemion, Jason; Murdoch, Peter S.
2010-01-01
Water-quality samples were collected from the Upper Delaware Scenic and Recreational River (UPDE) and its tributaries during the period October 1, 2005, to September 30, 2007, to document existing water quality, determine relations between land use and water quality, and identify areas of water-quality concern. A tiered water-quality monitoring framework was used, with the tiers consisting of intensively sampled sites, gradient sites representing the range of land uses present in the basin, and regional stream-survey sites. Median nitrate and total phosphorous concentrations were 1.15 and 0.01 mg/L (milligrams per liter) for three sites on the mainstem Delaware River, 1.27 and 0.009 mg/L for the East Branch Delaware River, 2.04 and 0.01 mg/L for the West Branch Delaware River, and 0.68 and 0.006 mg/L for eight tributaries that represent the range of land uses resent in the basin, respectively. The percentage of agricultural land varied by basin from 0 to 30 percent and the percentage of suburbanization varied from 0 to 17 percent. There was a positive correlation between the percentage of agricultural land use in a basin and observed concentrations of acid neutralizing capacity, calcium, potassium, nitrate, and total dissolved nitrogen, whereas no correlation between the percentage of suburbanization and water quality was detected. Results of stream surveys showed that nitrate concentrations in 55 to 65 percent of the UPDE Basin exceeded the nitrate reference condition and a suggested water-quality guideline for ecological impairment in New York State (0.98 mg/L) during the spring. Many of the affected parts of the basin were more than 90 percent forested and showed signs of episodic acidification, indicating that the long-term effects of acid deposition play a role in the high nitrate levels. Nitrate concentrations in 75 percent of samples collected from agricultural sites exceeded the suggested nitrate water-quality guideline for ecological impairment. Concentrations of nitrate and total phosphorous in samples collected from agricultural sites also were twice and 25 percent higher than those in samples from reference sites, respectively.
Rogers, Karyne M; Nicolini, Eric; Gauthier, Virginie
2012-09-01
Nitrate concentrations, water isotopes (δ(2)H and δ(18)O(water)) and associated nitrate isotopes (δ(15)N(nitrate) and δ(18)O(nitrate)) from 10 drinking water wells, 5 fresh water springs and the discharge from 3 wastewater treatment stations in Réunion Island, located in the Indian Ocean, were analysed. We used a multi isotopic approach to investigate the extent of nitrate contamination, nitrate formation altitude and source of nitrates in Réunion Island's principal aquifer. Water from these study sites contained between 0.1 and 85.3 mg/L nitrate. δ(15)N(nitrate) values between +6 and +14‰ suggested the main sources of contamination were animal and/or human waste, rather than inorganic (synthetic) fertilisers, infiltrating through the subsurface into the saturated zone, due to rainfall leaching of the unsaturated zone at various altitudes of precipitation. Based on δ(15)N(nitrate) values alone, it was not possible to distinguish between animal and human activities responsible for the contamination of each specific catchment. However, using a multi isotope approach (δ(18)O(water) and δ(15)N(nitrate)), it was possible to relate the average altitude of rainfall infiltration (δ(18)O(water)) associated with the nitrate contamination (δ(18)O(nitrate)). This relationship between land use, rainfall recharge altitude and isotopic composition (δ(15)N(nitrate) and δ(18)O(water)) discriminated between the influences of human waste at lower (below 600 m elevation) or animal derived contamination (at elevations between 600 and 1300 m). By further comparing the theoretical altitude of nitrate formation calculated by the δ(18)O(nitrate), it was possible to determine that only 5 out of 15 fresh water wells and springs followed the conservative nitrate formation mechanism of 2/3δ(18)O(water)+1/3δ(18)O(air), to give nitrate formation altitudes which corresponded to land use activities. Copyright © 2012 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Pennino, M. J.; Kaushal, S. S.; Mayer, P. M.; Utz, R. M.; Cooper, C. A.
2015-12-01
An improved understanding of sources and timing of water and nutrient fluxes associated with urban stream restoration is critical for guiding effective watershed management. We investigated how sources, fluxes, and flowpaths of water, carbon (C), nitrogen (N), and phosphorus (P) shift in response to differences in stream restoration and sanitary infrastructure. We compared a restored stream with 3 unrestored streams draining urban development and stormwater management over a 3 year period. We found that there was significantly decreased peak discharge in response to precipitation events following stream restoration. Similarly, we found that the restored stream showed significantly lower monthly peak runoff (9.4 ± 1.0 mm d-1) compared with two urban unrestored streams (ranging from 44.9 ± 4.5 to 55.4 ± 5.8 mm d-1) draining higher impervious surface cover. Peak runoff in the restored stream was more similar to a less developed stream draining extensive stormwater management (13.2 ± 1.9 mm d-1). Interestingly, the restored stream exported most carbon, nitrogen, and phosphorus loads at relatively lower streamflow than the 2 more urban streams, which exported most of their loads at higher and less frequent streamflow. Annual exports of total carbon (6.6 ± 0.5 kg ha-1 yr-1), total nitrogen (4.5 ± 0.3 kg ha-1 yr-1), and total phosphorus (161 ± 15 g ha-1 yr-1) were significantly lower in the restored stream compared to both urban unrestored streams (p < 0.05) and similar to the stream draining stormwater management. Although stream restoration appeared to potentially influence hydrology to some degree, nitrate isotope data suggested that 55 ± 1 % of the nitrate in the restored stream was derived from leaky sanitary sewers (during baseflow), similar to the unrestored streams. Longitudinal synoptic surveys of water and nitrate isotopes along all 4 watersheds suggested the importance of urban groundwater contamination from leaky piped infrastructure. Urban groundwater contamination was also suggested by additional tracer measurements including fluoride (added to drinking water) and iodide (contained in dietary salt). Our results suggest that integrating stream restoration with restoration of aging sanitary infrastructure can be critical to more effectively minimize watershed nutrient export. Given that both stream restoration and sanitary pipe repairs both involve extensive channel manipulation, they can be considered simultaneously in management strategies. In addition, ground water can be a major source of nutrient fluxes in urban watersheds, which has been less considered compared with upland sources and storm drains. Goundwater sources, fluxes, and flowpath should also be targeted in efforts to improve stream restoration strategies and prioritize hydrologic "hot spots" along watersheds where stream restoration is most likely to succeed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, Geoffrey Wayne
2016-03-16
This document identifies scope and some general procedural steps for performing Remediated Nitrate Salt (RNS) Surrogate Formulation and Testing. This Test Plan describes the requirements, responsibilities, and process for preparing and testing a range of chemical surrogates intended to mimic the energetic response of waste created during processing of legacy nitrate salts. The surrogates developed are expected to bound1 the thermal and mechanical sensitivity of such waste, allowing for the development of process parameters required to minimize the risk to worker and public when processing this waste. Such parameters will be based on the worst-case kinetic parameters as derived frommore » APTAC measurements as well as the development of controls to mitigate sensitivities that may exist due to friction, impact, and spark. This Test Plan will define the scope and technical approach for activities that implement Quality Assurance requirements relevant to formulation and testing.« less
Urban Mining of E-Waste is Becoming More Cost-Effective Than Virgin Mining.
Zeng, Xianlai; Mathews, John A; Li, Jinhui
2018-04-17
Stocks of virgin-mined materials utilized in linear economic flows continue to present enormous challenges. E-waste is one of the fastest growing waste streams, and threatens to grow into a global problem of unmanageable proportions. An effective form of management of resource recycling and environmental improvement is available, in the form of extraction and purification of precious metals taken from waste streams, in a process known as urban mining. In this work, we demonstrate utilizing real cost data from e-waste processors in China that ingots of pure copper and gold could be recovered from e-waste streams at costs that are comparable to those encountered in virgin mining of ores. Our results are confined to the cases of copper and gold extracted and processed from e-waste streams made up of recycled TV sets, but these results indicate a trend and potential if applied across a broader range of e-waste sources and metals extracted. If these results can be extended to other metals and countries, they promise to have positive impact on waste disposal and mining activities globally, as the circular economy comes to displace linear economic pathways.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fischer, D.K.; Gitt, M.; Williams, G.A.
1991-07-01
The objective of this document is to provide a resource for all states and compact regions interested in promoting the minimization of low-level radioactive waste (LLW). This project was initiated by the Commonwealth of Massachusetts, and Massachusetts waste streams have been used as examples; however, the methods of analysis presented here are applicable to similar waste streams generated elsewhere. This document is a guide for states/compact regions to use in developing a system to evaluate and prioritize various waste minimization techniques in order to encourage individual radioactive materials users (LLW generators) to consider these techniques in their own independent evaluations.more » This review discusses the application of specific waste minimization techniques to waste streams characteristic of three categories of radioactive materials users: (1) industrial operations using radioactive materials in the manufacture of commercial products, (2) health care institutions, including hospitals and clinics, and (3) educational and research institutions. Massachusetts waste stream characterization data from key radioactive materials users in each category are used to illustrate the applicability of various minimization techniques. The utility group is not included because extensive information specific to this category of LLW generators is available in the literature.« less
Waste minimization for commercial radioactive materials users generating low-level radioactive waste
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fischer, D.K.; Gitt, M.; Williams, G.A.
1991-07-01
The objective of this document is to provide a resource for all states and compact regions interested in promoting the minimization of low-level radioactive waste (LLW). This project was initiated by the Commonwealth of Massachusetts, and Massachusetts waste streams have been used as examples; however, the methods of analysis presented here are applicable to similar waste streams generated elsewhere. This document is a guide for states/compact regions to use in developing a system to evaluate and prioritize various waste minimization techniques in order to encourage individual radioactive materials users (LLW generators) to consider these techniques in their own independent evaluations.more » This review discusses the application of specific waste minimization techniques to waste streams characteristic of three categories of radioactive materials users: (1) industrial operations using radioactive materials in the manufacture of commercial products, (2) health care institutions, including hospitals and clinics, and (3) educational and research institutions. Massachusetts waste stream characterization data from key radioactive materials users in each category are used to illustrate the applicability of various minimization techniques. The utility group is not included because extensive information specific to this category of LLW generators is available in the literature.« less
Lambert, Rebecca B.; Opsahl, Stephen P.; Musgrove, MaryLynn
2017-12-22
Located in south-central Texas, the Geronimo Creek and Plum Creek watersheds have long been characterized by elevated nitrate concentrations. From April 2015 through March 2016, an assessment was done by the U.S. Geological Survey, in cooperation with the Guadalupe-Blanco River Authority and the Texas State Soil and Water Conservation Board, to characterize nitrate concentrations and to document possible sources of elevated nitrate in these two watersheds. Water-quality samples were collected from stream, spring, and groundwater sites distributed across the two watersheds, along with precipitation samples and wastewater treatment plant (WWTP) effluent samples from the Plum Creek watershed, to characterize endmember concentrations and isotopic compositions from April 2015 through March 2016. Stream, spring, and groundwater samples from both watersheds were collected during four synoptic sampling events to characterize spatial and temporal variations in water quality and chemical loadings. Water-quality and -quantity data from the WWTPs and stream discharge data also were considered. Samples were analyzed for major ions, selected trace elements, nutrients, and stable isotopes of water and nitrate.The dominant land use in both watersheds is agriculture (cultivated crops, rangeland, and grassland and pasture). The upper part of the Plum Creek watershed is more highly urbanized and has five major WWTPs; numerous smaller permitted wastewater outfalls are concentrated in the upper and central parts of the Plum Creek watershed. The Geronimo Creek watershed, in contrast, has no WWTPs upstream from or near the sampling sites.Results indicate that water quality in the Geronimo Creek watershed, which was evaluated only during base-flow conditions, is dominated by groundwater, which discharges to the stream by numerous springs at various locations. Nitrate isotope values for most Geronimo Creek samples were similar, which indicates that they likely have a common source (or sources) of nitrate. Nitrate sources in the Geronimo Creek watershed include a predominance of nitrate from fertilizer applications, as well as a contribution from septic systems. Additional nitrate loading from these sources is ongoing. Chemical loadings of dissolved solids, chloride, and sulfate varied little among sampling events and were low at most sites because of low streamflow.In contrast to the Geronimo Creek watershed, nitrate sources in the Plum Creek watershed are dominated by effluent discharge from the major WWTPs in the upper and central parts of the watershed. Results indicate that discharge from these WWTPs accounts for the majority of base flow in the watershed. Nitrate concentrations in Plum Creek were dependent on flow conditions, with the highest concentrations measured at lower flows, when flow is dominated by WWTP effluent discharge. In addition to WWTP effluent discharge, the Plum Creek watershed, similar to the Geronimo Creek watershed, also is affected by historical and current loading of nitrate from fertilizer applications and from septic systems in the watershed. Chemical loadings of dissolved solids, chloride, sulfate, and nitrate in Plum Creek at lower flow conditions are highest at the upstream sites and decrease downstream as distance from the WWTPs increases, which is consistent with WWTP effluent as an important control on water quality. Under higher flow conditions, however, nitrate loads to Plum Creek increased by about a factor of three. These higher nitrate loads cannot be accounted for by WWTP effluent discharge from the five major WWTPs in the watershed. This additional loading indicates that nitrate is exported from the northeastern part of the watershed. In the lower part of the Plum Creek watershed, higher concentrations of dissolved solids, chloride, and sulfate occur, which might be affected by produced water associated with oil and gas exploration, or mixing with saline groundwater.
Coupled Spatio-Temporal Patterns of Solute Transport, Metabolism and Nutrient Uptake in Streams
NASA Astrophysics Data System (ADS)
Kurz, M. J.; Schmidt, C.
2017-12-01
Slower flow velocities and longer residence times within stream transient storage (TS) zones facilitate interaction between solutes and microbial communities, potentially increasing local rates of metabolic activity. Multiple factors, including channel morphology and substrate, variable hydrology, and seasonal changes in biological and physical parameters, result in changes in the solute transport dynamics and reactivity of TS zones over time and space. These changes would be expected to, in turn, influence rates of whole-stream ecosystem functions such as metabolism and nutrient uptake. However, the linkages between solute transport and ecosystem functioning within TS zones, and the contribution of TS zones to whole-stream functioning, are not always so straight forward. This may be due, in part, to methodological challenges. In this study we investigated the influence of stream channel hydro-morphology and substrate type on reach (103 m) and sub-reach (102 m) scale TS and ecosystem functioning. Patterns in solute transport, metabolism and nitrate uptake were tracked from April through October in two contrasting upland streams using several methods. The two streams, located in the Harz Mountains, Germany, are characterized by differing size (0.02 vs. 0.3 m3/s), dominant stream channel substrate (bedrock vs. alluvium) and sub-reach morphology (predominance of pools, riffles and glides). Solute transport parameters and respiration rates at the reach and sub-reach scale were estimated monthly from coupled pulse injections of the reactive tracer resazurin (Raz) and conservative tracers uranine and salt. Raz, a weakly fluorescent dye, irreversibly transforms to resorufin (Rru) under mildly reducing conditions, providing a proxy for aerobic respiration. Daily rates of primary productivity, respiration and nitrate retention at the reach scale were estimated using the diel cycles in dissolved oxygen and nitrate concentrations measured by in-situ sensors. Preliminary results indicate distinct differences in common metrics of TS and Raz transformation rates within and between the two streams. However, transformation rates and TS metrics are not well correlated, indicating complexities in the relationship between solute transport dynamics and metabolism in streams.
Harden, Stephen L.; Cuffney, Thomas F.; Terziotti, Silvia; Kolb, Katharine R.
2013-01-01
Data collected between 1997 and 2008 at 48 stream sites were used to characterize relations between watershed settings and stream nutrient yields throughout central and eastern North Carolina. The focus of the investigation was to identify environmental variables in watersheds that influence nutrient export for supporting the development and prioritization of management strategies for restoring nutrient-impaired streams. Nutrient concentration data and streamflow data compiled for the 1997 to 2008 study period were used to compute stream yields of nitrate, total nitrogen (N), and total phosphorus (P) for each study site. Compiled environmental data (including variables for land cover, hydrologic soil groups, base-flow index, streams, wastewater treatment facilities, and concentrated animal feeding operations) were used to characterize the watershed settings for the study sites. Data for the environmental variables were analyzed in combination with the stream nutrient yields to explore relations based on watershed characteristics and to evaluate whether particular variables were useful indicators of watersheds having relatively higher or lower potential for exporting nutrients. Data evaluations included an examination of median annual nutrient yields based on a watershed land-use classification scheme developed as part of the study. An initial examination of the data indicated that the highest median annual nutrient yields occurred at both agricultural and urban sites, especially for urban sites having large percentages of point-source flow contributions to the streams. The results of statistical testing identified significant differences in annual nutrient yields when sites were analyzed on the basis of watershed land-use category. When statistical differences in median annual yields were noted, the results for nitrate, total N, and total P were similar in that highly urbanized watersheds (greater than 30 percent developed land use) and (or) watersheds with greater than 10 percent point-source flow contributions to streamflow had higher yields relative to undeveloped watersheds (having less than 10 and 15 percent developed and agricultural land uses, respectively) and watersheds with relatively low agricultural land use (between 15 and 30 percent). The statistical tests further indicated that the median annual yields for total P were statistically higher for watersheds with high agricultural land use (greater than 30 percent) compared to the undeveloped watersheds and watersheds with low agricultural land use. The total P yields also were higher for watersheds with low urban land use (between 10 and 30 percent developed land) compared to the undeveloped watersheds. The study data indicate that grouping and examining stream nutrient yields based on the land-use classifications used in this report can be useful for characterizing relations between watershed settings and nutrient yields in streams located throughout central and eastern North Carolina. Compiled study data also were analyzed with four regression tree models as a means of determining which watershed environmental variables or combination of variables result in basins that are likely to have high or low nutrient yields. The regression tree analyses indicated that some of the environmental variables examined in this study were useful for predicting yields of nitrate, total N, and total P. When the median annual nutrient yields for all 48 sites were evaluated as a group (Model 1), annual point-source flow yields had the greatest influence on nitrate and total N yields observed in streams, and annual streamflow yields had the greatest influence on yields of total P. The Model 1 results indicated that watersheds with higher annual point-source flow yields had higher annual yields of nitrate and total N, and watersheds with higher annual streamflow yields had higher annual yields of total P. When sites with high point-source flows (greater than 10 percent of total streamflow) were excluded from the regression tree analyses (Models 2–4), the percentage of forested land in the watersheds was identified as the primary environmental variable influencing stream yields for both total N and total P. Models 2, 3 and 4 did not identify any watershed environmental variables that could adequately explain the observed variability in the nitrate yields among the set of sites examined by each of these models. The results for Models 2, 3, and 4 indicated that watersheds with higher percentages of forested land had lower annual total N and total P yields compared to watersheds with lower percentages of forested land, which had higher median annual total N and total P yields. Additional environmental variables determined to further influence the stream nutrient yields included median annual percentage of point-source flow contributions to the streams, variables of land cover (percentage of forested land, agricultural land, and (or) forested land plus wetlands) in the watershed and (or) in the stream buffer, and drainage area. The regression tree models can serve as a tool for relating differences in select watershed attributes to differences in stream yields of nitrate, total N, and total P, which can provide beneficial information for improving nutrient management in streams throughout North Carolina and for reducing nutrient loads to coastal waters.
Stream chemistry following a forest fire and urea fertilization in north-central Washington.
Arthur R. Tiedemann
1973-01-01
During 2 years of study, nitrate-N in streamflow increased from background levels of 0.005 part per million (p.p.m.) in a control stream to 0.042 and 0.310 p.p.m. in streams from burned and burned, urea-fertilized watersheds, respectively. Cation concentration increased on the burned, unfertilized watershed, but because of dilution effects,...
Waste minimisation in a hard chromiun plating Small Medium Enterprise (SME).
Viguri, J R; Andrés, A; Irabien, A
2002-01-01
The high potential of waste stream minimisation in the metal finishing sector justifies specific studies of Small and Medium Enterprises (SME). In this work, the minimisation options of the wastes generated in a hard chromium plating activity have been analysed. The study has been performed in a small job shop company, which works in batch mode with big pieces. A process flowsheet after connecting the unit operations and determining the process inputs (raw and secondary materials) and outputs (waste streams) has been carried out. The main properties, quantity and current management of the waste streams have been shown. The obvious lack of information has been identified and finally the waste minimisation options that could be adopted by the company have been recorded.
Development of an Integrated Waste Plan for Chalk River Laboratories - 13376
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jones, L.
2013-07-01
To further its Strategic Planning, the Atomic Energy of Canada Limited (AECL) required an effective approach to developing a fully integrated waste plan for its Chalk River Laboratories (CRL) site. Production of the first Integrated Waste Plan (IWP) for Chalk River was a substantial task involving representatives from each of the major internal stakeholders. Since then, a second revision has been produced and a third is underway. The IWP remains an Interim IWP until all gaps have been resolved and all pathways are at an acceptable level of detail. Full completion will involve a number of iterations, typically annually formore » up to six years. The end result of completing this process is a comprehensive document and supporting information that includes: - An Integrated Waste Plan document summarizing the entire waste management picture in one place; - Details of all the wastes required to be managed, including volume and timings by waste stream; - Detailed waste stream pathway maps for the whole life-cycle for each waste stream to be managed from pre-generation planning through to final disposition; and - Critical decision points, i.e. decisions that need to be made and timings by when they need to be made. A waste inventory has been constructed that serves as the master reference inventory of all waste that has been or is committed to be managed at CRL. In the past, only the waste that is in storage has been effectively captured, and future predictions of wastes requiring to be managed were not available in one place. The IWP has also provided a detailed baseline plan at the current level of refinement. Waste flow maps for all identified waste streams, for the full waste life cycle complete to disposition have been constructed. The maps identify areas requiring further development, and show the complexities and inter-relationships between waste streams. Knowledge of these inter-dependencies is necessary in order to perform effective options studies for enabling facilities that may be necessary for multiple related waste streams. The next step is to engage external stakeholders in the optioneering work required to provide enhanced confidence that the path forward identified within future iterations of the IWP will be acceptable to all. (authors)« less
NASA Astrophysics Data System (ADS)
Leschik, S.; Musolff, A.; Reinstorf, F.; Strauch, G.; Schirmer, M.
2009-05-01
Urban streams receive effluents of wastewater treatment plants and untreated wastewater during combined sewer overflow events. In the case of losing streams substances, which originate from wastewater, can reach the groundwater and deteriorate its quality. The estimation of mass flow rates Mex from losing streams to the groundwater is important to support groundwater management strategies, but is a challenging task. Variable inflow of wastewater with time-dependent concentrations of wastewater constituents causes a variable water composition in urban streams. Heterogeneities in the structure of the streambed and the connected aquifer lead, in combination with this variable water composition, to heterogeneous concentration patterns of wastewater constituents in the vicinity of urban streams. Groundwater investigation methods based on conventional point sampling may yield unreliable results under these conditions. Integral Pumping Tests (IPT) can overcome the problem of heterogeneous concentrations in an aquifer by increasing the sampled volume. Long-time pumping (several days) and simultaneous sampling yields reliable average concentrations Cav and mass flow rates Mcp for virtual control planes perpendicular to the natural flow direction. We applied the IPT method in order to estimate Mex of a stream section in Leipzig (Germany). The investigated stream is strongly influenced by combined sewer overflow events. Four pumping wells were installed up- and downstream of the stream section and operated for a period of five days. The study was focused on four inorganic (potassium, chloride, nitrate and sulfate) and two organic (caffeine and technical-nonylphenol) wastewater constituents with different transport properties. The obtained concentration-time series were used in combination with a numerical flow model to estimate Mcp of the respective wells. The difference of the Mcp's between up- and downstream wells yields Mex of wastewater constituents that increase downstream of the stream. In order to confirm the obtained Mcp's concentrations of additional measurements in the investigated stream were compared with the concentrations in the groundwater up- and downstream of the stream section. The results revealed increased Mcp's downstream of the stream section for chloride, potassium and nitrate, whereas Mcp of sulfate was decreased. Micropollutants caffeine and technical-nonylphenol showed decreased Mcp's downstream of the stream section in 75 % of the cases. Values of Mex could only be given for chloride, potassium, nitrate and caffeine. The comparison of concentrations in the stream with those in the groundwater points to the streambed as a zone where mass accumulation and degradation processes occur. The obtained results imply that the applied method can provide reliable data about the influence of losing streams on groundwater quality.
N-SINK - reduction of waste water nitrogen load
NASA Astrophysics Data System (ADS)
Aalto, Sanni; Tiirola, Marja; Arvola, Lauri; Huotari, Jussi; Tulonen, Tiina; Rissanen, Antti; Nykänen, Hannu
2014-05-01
Protection of the Baltic Sea from eutrophication is one of the key topics in the European Union environmental policy. One of the main anthropogenic sources of nitrogen (N) loading into Baltic Sea are waste water treatment plants, which are currently capable in removing only 40-70% of N. European commission has obliged Finland and other Baltic states to reduce nitrate load, which would require high monetary investments on nitrate removal processes in treatment plants. In addition, forced denitrification in treatment plants would increase emissions of strong greenhouse gas N2O. In this project (LIFE12 FI/ENV/597 N-SINK) we will develop and demonstrate a novel economically feasible method for nitrogen removal using applied ecosystem services. As sediment is known to have enormous capacity to reduce nitrate to nitrogen gas through denitrification, we predict that spatial optimization of the waste water discharge would be an efficient way to reduce nitrate-based load in aquatic systems. A new sediment filtration approach, which will increase both the area and time that nitrified waste water will be in contact with the reducing microbes of the sediment, is tested. Compared to the currently implemented practice, where purified waste water is discharged though one-point outlet system, we expect that sediment filtration system will result in more efficient denitrification and decreased N load to aquatic system. We will conduct three full-scale demonstrations in the receiving water bodies of waste water treatment plants in Southern and Central Finland. The ecosystem effects of sediment filtration system will be monitored. Using the most advanced stable isotope techniques will allow us accurately measure denitrification and unfavoured DNRA (reduction of nitrite to ammonium) activity.
NASA Astrophysics Data System (ADS)
Fuss, Colin B.; Driscoll, Charles T.; Campbell, John L.
2015-11-01
Atmospheric acid deposition of sulfate and nitrate has declined markedly in the northeastern United States due to emissions controls. We investigated long-term trends in soil water (1984-2011) and stream water (1982-2011) chemistry along an elevation gradient of a forested watershed to evaluate the progress of recovery of drainage waters from acidic deposition at the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire, USA. We found slowed losses of base cations from soil and decreased mobilization of dissolved inorganic aluminum. Stream water pH at the watershed outlet increased at a rate of 0.01 units yr-1, and the acid neutralizing capacity (ANC) gained 0.88 µeq L-1 yr-1. Dissolved organic carbon generally decreased in stream water and soil solutions, contrary to trends observed at many North American and European sites. We compared whole-year hydrochemical trends with those during snowmelt, which is the highest-flow and lowest ANC period of the year, indicative of episodic acidification. Stream water during snowmelt had long-term trends of increasing ANC and pH at a rate very similar to the whole-year record, with closely related steady decreases in sulfate. A more rapid decline in stream water nitrate during snowmelt compared with the whole-year trend may be due, in part, to the marked decrease in atmospheric nitrate deposition during the last decade. The similarity between the whole-year trends and those of the snowmelt period is an important finding that demonstrates a consistency between recovery from chronic acidification during base flow and abatement of snowmelt acidification.
Beaver Ponds: Resurgent Nitrogen Sinks for Rural Watersheds in the Northeastern United States.
Lazar, Julia G; Addy, Kelly; Gold, Arthur J; Groffman, Peter M; McKinney, Richard A; Kellogg, Dorothy Q
2015-09-01
Beaver-created ponds and dams, on the rise in the northeastern United States, reshape headwater stream networks from extensive, free-flowing reaches to complexes of ponds, wetlands, and connecting streams. We examined seasonal and annual rates of nitrate transformations in three beaver ponds in Rhode Island under enriched nitrate-nitrogen (N) conditions through the use of N mass balance techniques on soil core mesocosm incubations. We recovered approximately 93% of the nitrate N from our mesocosm incubations. Of the added nitrate N, 22 to 39% was transformed during the course of the incubation. Denitrification had the highest rates of transformation (97-236 mg N m d), followed by assimilation into the organic soil N pool (41-93 mg N m d) and ammonium generation (11-14 mg N m d). Our denitrification rates exceeded those in several studies of freshwater ponds and wetlands; however, rates in those ecosystems may have been limited by low concentrations of nitrate. Assuming a density of 0.7 beaver ponds km of catchment area, we estimated that in nitrate-enriched watersheds, beaver pond denitrification can remove approximately 50 to 450 kg nitrate N km catchment area. In rural watersheds of southern New England with high N loading (i.e., 1000 kg km), denitrification from beaver ponds may remove 5 to 45% of watershed nitrate N loading. Beaver ponds represent a relatively new and substantial sink for watershed N if current beaver populations persist. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
Rasiah, V; Armour, J D; Cogle, A L
2005-01-01
The impact of fertilised cropping on nitrate-N dynamics in groundwater (GW) was assessed in a catchment from piezometers installed: (i) to different depths, (ii) in different soil types, (iii) on different positions on landscape, and (iv) compared with the Australian and New Zealand Environmental and Conservation Council guideline values provided for different aquatic ecosystems. The GW and NO(3)-N concentration dynamics were monitored in 39 piezometer wells, installed to 5-90 m depth, under fertilized sugarcane (Saccharum officinarum-S) in the Johnstone River Catchment, Australia, from 1999 January through September 2002. The median nitrate-N concentration ranged from 14 to 1511 microg L(-1), and the 80th percentile from 0 to 1341 microg L(-1). In 34 out of the 39 piezometer wells the 80th percentile or 80% of the nitrate-N values were higher than 30 microg L(-1), which is the maximum trigger value provided in the ANZECC table for sustainable health of different aquatic ecosystems. Nitrate-N concentration decreased with increasing well depth, increasing depth of water in wells, and with decreasing relief on landscape. Nitrate-N was higher in alluvial soil profiles than on those formed in-situ. Nitrate-N increased with increasing rainfall at the beginning of the rainy season, fluctuated during the peak rainy period, and then decreased when the rain ceased. The rapid decrease in GW after the rains ceased suggested potential existed for nitrate-N to be discharged as lateral-flow into streams. This may contribute towards the deterioration in the health of down-stream aquatic ecosystems.
The upcycling of post-industrial PP/PET waste streams through in-situ microfibrillar preparation
NASA Astrophysics Data System (ADS)
Delva, Laurens; Ragaert, Kim; Cardon, Ludwig
2015-12-01
Post-industrial plastic waste streams can be re-used as secondary material streams for polymer processing by extrusion or injection moulding. One of the major commercially available waste stream contains polypropylene (PP) contaminated with polyesters (mostly polyethylene tereftalate - PET). An important practical hurdle for the direct implementation of this waste stream is the immiscibility of PP and PET in the melt, which leads to segregation within the polymer structure and adversely affects the reproducibility and mechanical properties of the manufactured parts. It has been indicated in literature that the creation of PET microfibrils in the PP matrix could undo these drawbacks and upcycle the PP/PET combination. Within the current research, a commercially available virgin PP/PET was evaluated for the microfibrillar preparation. The mechanical (tensile and impact) properties, thermal properties and morphology of the composites were characterized at different stages of the microfibrillar preparation.
Krishna Mohan, Tulasi Venkata; Renu, Kadali; Nancharaiah, Yarlagadda Venkata; Satya Sai, Pedapati Murali; Venugopalan, Vayalam Purath
2016-02-01
A 6-L sequencing batch reactor (SBR) was operated for development of granular sludge capable of denitrification of high strength nitrates. Complete and stable denitrification of up to 5420 mg L(-1) nitrate-N (2710 mg L(-1) nitrate-N in reactor) was achieved by feeding simulated nitrate waste at a C/N ratio of 3. Compact and dense denitrifying granular sludge with relatively stable microbial community was developed during reactor operation. Accumulation of large amounts of nitrite due to incomplete denitrification occurred when the SBR was fed with 5420 mg L(-1) NO3-N at a C/N ratio of 2. Complete denitrification could not be achieved at this C/N ratio, even after one week of reactor operation as the nitrite levels continued to accumulate. In order to improve denitrification performance, the reactor was fed with nitrate concentrations of 1354 mg L(-1), while keeping C/N ratio at 2. Subsequently, nitrate concentration in the feed was increased in a step-wise manner to establish complete denitrification of 5420 mg L(-1) NO3-N at a C/N ratio of 2. The results show that substrate concentration plays an important role in denitrification of high strength nitrate by influencing nitrite accumulation. Complete denitrification of high strength nitrates can be achieved at lower substrate concentrations, by an appropriate acclimatization strategy. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
Precipitation process for the removal of technetium values from nuclear waste solutions
Walker, D.D.; Ebra, M.A.
1985-11-21
High efficiency removal of techetium values from a nuclear waste stream is achieved by addition to the waste stream of a precipitant contributing tetraphenylphosphonium cation, such that a substantial portion of the technetium values are precipitated as an insoluble pertechnetate salt.
INTELLIGENT DECISION SUPPORT FOR WASTE MINIMIZATION IN ELECTROPLATING PLANTS. (R824732)
Wastewater, spent solvent, spent process solutions, and sludge are the major waste streams generated in large volumes daily in electroplating plants. These waste streams can be significantly minimized through process modification and operational improvement. I...
Techniques for Measurement of Nitrate Movement in Soils
NASA Technical Reports Server (NTRS)
Broadbent, F. E.
1971-01-01
Contamination of surface and ground waters with nitrate usually involves leaching through soil of nitrate produced by mineralization of soil organic matter, decomposition of animal wastes or plant residues, or derived from fertilizers. Nitrate concentrations in the soil solution may be measured by several chemical procedures or by the nitrate electrode. since nitrate is produced throughout the soil mass it is difficult to identify a source of nitrate contamination by conventional means. This problem can be solved by use of N-15-enriched or N-15-depleted materials as tracers. The latter is particularly attractive because of the negligible possibility of the tracer hazardous to health.
Stelzer, Robert S.; Scott, J. Thad; Bartsch, Lynn; Parr, Thomas B.
2014-01-01
Organic carbon supply is linked to nitrogen transformation in ecosystems. However, the role of organic carbon quality in nitrogen processing is not as well understood. We determined how the quality of particulate organic carbon (POC) influenced nitrogen transformation in stream sediments by burying identical quantities of varying quality POC (northern red oak (Quercus rubra) leaves, red maple (Acer rubrum) leaves, red maple wood) in stream mesocosms and measuring the effects on nitrogen retention and denitrification compared to a control of combusted sand. We also determined how POC quality affected the quantity and quality of dissolved organic carbon (DOC) and dissolved oxygen concentration in groundwater. Nitrate and total dissolved nitrogen (TDN) retention were assessed by comparing solute concentrations and fluxes along groundwater flow paths in the mesocosms. Denitrification was measured by in situ changes in N2 concentrations (using MIMS) and by acetylene block incubations. POC quality was measured by C:N and lignin:N ratios and DOC quality was assessed by fluorescence excitation emission matrix spectroscopy. POC quality had strong effects on nitrogen processing. Leaf treatments had much higher nitrate retention, TDN retention and denitrification rates than the wood and control treatments and red maple leaf burial resulted in higher nitrate and TDN retention rates than burial of red oak leaves. Leaf, but not wood, burial drove pore water to severe hypoxia and leaf treatments had higher DOC production and different DOC chemical composition than the wood and control treatments. We think that POC quality affected nitrogen processing in the sediments by influencing the quantity and quality of DOC and redox conditions. Our results suggest that the type of organic carbon inputs can affect the rates of nitrogen transformation in stream ecosystems.
Tracing the source and fate of nitrate in contemporary mixed land-use surface water systems
NASA Astrophysics Data System (ADS)
Stewart, S. D.; Young, M. B.; Horton, T. W.; Harding, J. S.
2011-12-01
Nitrogenous fertilizers increase agricultural productivity, ultimately feeding the planet. Yet, it is possible to have too much of a good thing, and nitrogen is no exception. When in excess nitrogen has been shown to accelerate eutrophication of water bodies, and act as a chronic toxin (e.g. methemoglobinemia). As land-use intensity continues to rise in response to increases in agricultural productivity, the risk of adverse effects of nitrogen loading on surface water bodies will also increase. Stable isotope proxies are potential tracers of nitrate, the most common nitrogenous phase in surface waters. Applying stable isotope proxies therefore presents an opportunity to identify and manage sources of excess nitrogen before aquatic systems are severely degraded. However, the heterogeneous nature of potential pollution sources themselves, and their distribution with a modified catchment network, make understanding this issue highly complex. The Banks Peninsula, an eroded late tertiary volcanic complex located on the east coast of the South Island New Zealand, presents a unique opportunity to study and understand the sources and fates of nitrate within streams in a contemporary mixed land-use setting. Within this small geographic area there a variety of agricultural activities are practiced, including: heavily fertilized golf courses; stands of regenerating native forest; and areas of fallow gorse (Ulex europaeus; a invasive N-fixing shrub). Each of these landuse classes has its own unique nitrogen budget. Multivariate analysis was used on stream nitrate concentrations to reveal that stream reaches dominated by gorse had significantly higher nitrate concentrations than other land-use classes. Nitrate δ15N & δ18O data from these sites show strong covariance, plotting along a distinct fractionation line (r2 = 0.96). This finding facilitates interpretation of what processes are controlling nitrate concentration within these systems. Further, complementary aquatic foodweb δ15N δ13C analyses of multiple species in various trophic positions allow for a unique, holistic insight in to the fate of gorse-derived nitrate at an ecosystem level. We present here physicochemical and stable isotopic data from a variety of aqueous and aquatic foodweb components. Data is generated using emerging and established analytical techniques, in order to explore links between foodweb ecology, ecosystem function, and fate and transport of excess nitrate along longitudinal gradients of mixed land-use catchments.
Technical Status Report: Preliminary Glass Formulation Report for INEEL HAW. Revision 1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peeler, D.; Reamer, I.; Vienna, J.
1998-03-01
Preliminary glass formulation work has been initiated at Pacific Northwest National Laboratory (PNNL) and the Savannah River Technology Center (SRTC) to support immobilization efforts of Idaho National Engineering and Environmental Laboratory (INEEL) high activity waste (HAW). Based on current pretreatment flow sheet assumptions, several glasses were fabricated and tested using an average `All Blend` waste stream composition which is dominated by the presence of ZrO{sub 2} (i.e., approximately 80 wt percent). The results of this initial work show that immobilization via vitrification is a viable option for a specific INEEL HAW waste stream. Waste loadings of at least 19 wtmore » percent can be achieved for the `All Blend` stream while maintaining targeted processing and product performance criteria. This waste loading translates into a ZrO{sub 2} content in excess of 15 wt percent in the final glass waste form. Frits developed for this work are based in the alkali borosilicate system. Although the results indicate that vitrification can be used to immobilize the `All Blend` waste stream, the glass compositions are by no means optimized.« less
USDA-ARS?s Scientific Manuscript database
Nutrients, particularly nitrate (NO3), can accumulate to very high levels within low exchange recirculation aquaculture systems (RAS) and negatively impact a number of cultured species. To prevent the harmful effects of nitrate accumulation and to dispose of concentrated waste biosolids, many RAS ar...
NASA Astrophysics Data System (ADS)
Wang, Meng; Lu, Baohong
2017-04-01
Nitrate is essential for the growth and survival of plants, animals and humans. However, excess nitrate in drinking water is regarded as a health hazard as it is linked to infant methemoglobinemia and esophageal cancer. Revealing nitrate characteristics and identifying its sources are fundamental for making effective water management strategies, but nitrate sources in multi-tributaries and mixed land covered watersheds remain unclear. It is difficult to determine the predominant NO3- sources using conventional water quality monitoring techniques. In our study, based on 20 surface water sampling sites for more than two years' monitoring from April 2012 to December 2014, water chemical and dual isotopic approaches (δ15N-NO3- and δ18O-NO3-) were integrated for the first time to evaluate nitrate characteristics and sources in the Huashan watershed, Jianghuai hilly region, East China. The results demonstrated that nitrate content in surface water was relatively low in the downstream (<10 mg/L), but spatial heterogeneities were remarkable among different sub-watersheds. Extremely high nitrate was observed at the source of the river in one of the sub-watersheds, which exhibited an exponential decline along the stream due to dilution, absorption by aquatic plants, and high forest cover. Although dramatically decline of nitrate occurred along the stream, denitrification was not found in surface water by analyzing δ15N-NO3- and δ18O-NO3- relationship. Proportional contributions of five potential nitrate sources (i.e., precipitation; manure and sewage; soil nitrogen; nitrate fertilizer; nitrate derived from ammonia fertilizer and rainfall) were estimated using a Bayesian isotope mixing model. Model results indicated nitrate sources varied significantly among different rainfall conditions, land use types, as well as anthropologic activities. In summary, coupling dual isotopes of nitrate (δ15N-NO3- and δ18O-NO3-, simultaneously) with a Bayesian isotope mixing model offers a useful and practical way to qualitatively analyze nitrate sources and transformations as well as quantitatively estimate the contributions of potential nitrate sources in surface water. With the assessment of nitrate sources and characteristics, effective management strategies can be implemented to reduce N export and improve water quality in this region.
PROCESS TRANSFER FUNCTIONS TO RELATE STREAM ECOLOGICAL CONDITION METRICS TO NITRATE RETENTION
Ecologists have developed hydrological metrics to characterize the nutrient processing capability of streams. In most cases these are used qualitatively to draw inferences on ecological function. In this work, several of these metrics have been integrated in a nonsteady state adv...
THE EFFECTS OF ECOSYSTEM RESTORATION ON NITROGEN PROCESSING IN AN URBAN MID-ATLANTIC PIEDMONT STREAM
Elevated nitrate levels in streams and groundwater pose human and ecological threats. The US Environmental Protection Agency, US Geological Survey, Institute of Ecosystem Studies, and Baltimore County Dept. of Environmental Protection and Resource Management are collaborating on...
Energy recovery system using an organic rankine cycle
Ernst, Timothy C
2013-10-01
A thermodynamic system for waste heat recovery, using an organic rankine cycle is provided which employs a single organic heat transferring fluid to recover heat energy from two waste heat streams having differing waste heat temperatures. Separate high and low temperature boilers provide high and low pressure vapor streams that are routed into an integrated turbine assembly having dual turbines mounted on a common shaft. Each turbine is appropriately sized for the pressure ratio of each stream.
NASA Astrophysics Data System (ADS)
Midor, Katarzyna; Jąderko, Karolina
2017-11-01
The problem of overproduction of waste has been a local issue for many years. Since the new environment law came into effect, the current approach to waste management has changed significantly. The accessible technological possibilities of thermal waste treatment with the energy recovery set a new area of research over the process of choosing effective and rational way of calorific waste management. The objective of this article is to provide assessment results of the analysed energy potential in waste management system in the form of calorific waste stream. In includes all the activities and actions required to manage municipal solid waste from its inception to its final disposal i.e. collection, transport, treatment and disposal. The graphical representation of waste flow indicates the lost opportunities of waste energy recovery. Visual research method was supported and founded on value stream mapping. On the basis of the results were presented the directions of further improvement of calorific waste stream mapping for the purposes of implementation the thermal treatment technology in the selected waste management region.
WCATS: Waste Documentation, Course No. 8504
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simpson, Sandy
2016-04-14
This course was developed for individuals at Los Alamos National Laboratory (LANL) who characterize and document waste streams in the Waste Compliance and Tracking System (WCATS) according to Environmental Protection Agency (EPA) Department of Transportation (DOT) regulations, Department of Energy Orders, and other applicable criteria. When you have completed this course, you will be able to recognize how waste documentation enables LANL to characterize and classify hazardous waste for compliant treatment, storage, and disposal, identify the purpose of the waste stream profile (WSP), identify the agencies that provide guidance for waste management, and more.
Laverman, Anniet M; Cazier, Thibaut; Yan, Chen; Roose-Amsaleg, Céline; Petit, Fabienne; Garnier, Josette; Berthe, Thierry
2015-09-01
Antibiotics and antibiotic resistance genes have shown to be omnipresent in the environment. In this study, we investigated the effect of vancomycin (VA) on denitrifying bacteria in river sediments of a Waste Water Treatment Plant, receiving both domestic and hospital waste. We exposed these sediments continuously in flow-through reactors to different VA concentrations under denitrifying conditions (nitrate addition and anoxia) in order to determine potential nitrate reduction rates and changes in sedimentary microbial community structures. The presence of VA had no effect on sedimentary nitrate reduction rates at environmental concentrations, whereas a change in bacterial (16S rDNA) and denitrifying (nosZ) community structures was observed (determined by polymerase chain reaction-denaturing gradient gel electrophoresis). The bacterial and denitrifying community structure within the sediment changed upon VA exposure indicating a selection of a non-susceptible VA population.
In-Stream Microbial Denitrification Potential at Wastewater Treatment Plant Discharge Sites
NASA Astrophysics Data System (ADS)
Hill, N. B.; Rahm, B. G.; Shaw, S. B.; Riha, S. J.
2014-12-01
Reactive nitrogen loading from municipal sewage discharge provides point sources of nitrate (NO3-) to rivers and streams. Through microbially-mediated denitrification, NO3- can be converted to dinitrogen (N2) and nitrous oxide (N2O) gases, which are released to the atmosphere. Preliminary observations made throughout summer 2011 near a wastewater treatment plant (WWTP) outfall in the Finger Lakes region of New York indicated that NO3- concentrations downstream of the discharge pipe were lower relative to upstream concentrations. This suggested that nitrate processing was occurring more rapidly and completely than predicted by current models and that point "sources" can in some cases be point "sinks". Molecular assays and stable isotope analyses were combined with laboratory microcosm experiments and water chemistry analyses to better understand the mechanism of nitrate transformation. Nitrite reductase (nirS and nirK) and nitrous oxide reductase (nosZ) genes were detected in water and sediment samples using qPCR. Denitrifcation genes were present attached to stream sediment, in pipe biofilm, and in WWTP discharge water. A comparison of δ18-O and δ15-N signatures also supported the hypothesis that stream NO3- had been processed biotically. Results from microcosm experiments indicated that the NO3- transformations occur at the sediment-water interface rather than in the water column. In some instances, quantities of denitrification genes were at higher concentrations attached to sediment downstream of the discharge pipe than upstream of the pipe suggesting that the wastewater discharge may be enriching the downstream sediment and could promote in-stream denitrification.
Hernández-Apaolaza, L; Guerrero, F
2008-04-01
Waste products such as biosolids and wood wastes have been frequently used in container production of plants. The use of biosolids in agriculture is a beneficial mean of recycling the by-products of waste-water treatment. However, care must be taken to avoid environmental or human health problems via run-off and leaching. The objective of this work is to compare the retention capacity of cadmium, lead, zinc and nitrate between pine bark (PB) and coconut fibre (F) when mixed with increasing amounts of composted sewage sludge (CSS) (0%, 15% and 30% (v/v)). Substrates were packed into leaching columns and irrigated with deionised water every 2 days. Leachates were collected during 1 month, and nitrate, Zn, Cd, Pb, EC and pH were monitored along the experiment. PB columns leached lower amount of nitrate than the coconut fibre ones. The same trend was observed for Zn, Cd and Pb. It could be said, that in order to minimize the environmental risks of using sewage sludges our results indicate that it is preferred to mix the sludge with pine bark instead than with coconut husk.
Gregory P. Lewis
1999-01-01
The leaching of calcium and magnesium from forests by atmospherically-deposited strong acid anions (sulfate and nitrate) is evidenced in some watersheds by the positive correlation in stream water between concentrations of these base cations and acid anions.
Multi-discipline Waste Acceptance Process at the Nevada National Security Site - 13573
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carilli, Jhon T.; Krenzien, Susan K.
2013-07-01
The Nevada National Security Site low-level radioactive waste disposal facility acceptance process requires multiple disciplines to ensure the protection of workers, the public, and the environment. These disciplines, which include waste acceptance, nuclear criticality, safety, permitting, operations, and performance assessment, combine into the overall waste acceptance process to assess low-level radioactive waste streams for disposal at the Area 5 Radioactive Waste Management Site. Four waste streams recently highlighted the integration of these disciplines: the Oak Ridge Radioisotope Thermoelectric Generators and Consolidated Edison Uranium Solidification Project material, West Valley Melter, and classified waste. (authors)
NITRATE POLLUTION IN SHALLOW GROUNDWATER OF A HARD ROCK REGION IN SOUTH CENTRAL INDIA
NASA Astrophysics Data System (ADS)
Brindha, K.; Rajesh, R.; Murugan, R.; Elango, L.
2009-12-01
Groundwater forms a major source of drinking water in most parts of the world. Due to the lack of piped drinking water supply, the population in rural areas depend on the groundwater resources for domestic purposes. Hence, the quality of groundwater in such regions needs to be monitored regularly. Presence of high concentration of nitrate in groundwater used for drinking is a major problem in many countries as it causes health related problems. Most often infants are affected by the intake of high nitrate in drinking water and food. The present study was carried out with the objective of assessing the nitrate concentration in groundwater and determining the causes for nitrate in groundwater in parts of Nalgonda district in India which is located at a distance of about 135 km towards ESE direction from Hyderabad. Nitrate concentration in groundwater of this area was analysed by collecting groundwater samples from forty six representative wells. Samples were collected once in two months from March 2008 to March 2009. A total of 244 groundwater samples were collected during the study. Soil samples were collected from fifteen locations during May 2009 and the denitrifying bacteria were isolated from the soil using spread plate method. The nitrate concentration in groundwater samples were analysed in the laboratory using Metrohm 861 advanced compact ion chromatograph using appropriate standards. The highest concentration of nitrate recorded during the sampling period was 879.65mg/l and the lowest concentration was below detection limit. The maximum permissible limit of nitrate for drinking water as per Bureau of Indian Standards is 45mg/l. About 13% of the groundwater samples collected from this study area possessed nitrate concentration beyond this limit. The nitrate concentration was high in the southeastern part of the study area. This implies that the nitrate concentration in groundwater tends to increase along the flow direction. Application of fertilizers is one of the sources for nitrate in groundwater. The recharge of rainwater through the indiscriminately dumped animal wastes also adds to nitrate in groundwater. As the population of denitrifying microbes (Agrobacterium sp.) in the topsoil increased, the nitrate concentration in groundwater decreased. The wells in the investigated region have been demarcated into safe and unsafe wells for consumption of water with respect to nitrate. The quality of groundwater in this region must be improved by denitrifying the groundwater before using it for consumption. Reduced dependence on nitrogen-rich fertilizers can also lower the influx of nitrates to a large extent. As the dumping of animal waste is also a reason behind high nitrate in groundwater, it would be better to use them as a biofertilizer. Due to the detrimental biological effects of nitrate, treatment and prevention methods must be considered to protect groundwater aquifers from nitrate leaching. Moreover, it is also important to educate the local population about keeping their surroundings clean, alternate use of the animal waste (as fuel) and to follow hygienic sanitation practices.
Harrington, C.D.; Opie, J.V.
1958-07-01
The recovery of uranium values from uranium ore such as pitchblende is described. The ore is first dissolved in nitric acid, and a water soluble nitrate is added as a salting out agent. The resulting feed solution is then contacted with diethyl ether, whereby the bulk of the uranyl nitrate and a portion of the impurities are taken up by the ether. This acid ether extract is then separated from the aqueous raffinate, and contacted with water causing back extractioa of the uranyl nitrate and impurities into the water to form a crude liquor. After separation from the ether extract, this crude liquor is heated to about 118 deg C to obtain molten uranyl nitrate hexahydratc. After being slightly cooled the uranyl nitrate hexahydrate is contacted with acid free diethyl ether whereby the bulk of the uranyl nitrate is dissolved into the ethcr to form a neutral ether solution while most of the impurities remain in the aqueous waste. After separation from the aqueous waste, the resultant ether solution is washed with about l0% of its volume of water to free it of any dissolved impurities and is then contacted with at least one half its volume of water whereby the uranyl nitrate is extracted into the water to form an aqueous product solution.
NASA Astrophysics Data System (ADS)
Linhoff, B.; Norton, S.; Travis, R.; Romero, Z.; Waters, B.
2017-12-01
Nitrate contamination of groundwater is a major problem globally including within the Albuquerque Basin in New Mexico. Ingesting high concentrations of nitrate (> 10 mg/L as N) can lead to an increased risk of cancer and to methemoglobinemia in infants. Numerous anthropogenic sources of nitrate have been identified within the Albuquerque Basin including fertilizers, landfills, multiple sewer pipe releases, sewer lagoons, domestic septic leach fields, and a nitric acid line outfall. Furthermore, groundwater near ephemeral streams often exhibits elevated NO3 concentrations and high NO3/Cl ratios incongruous with an anthropogenic source. These results suggest that NO3 can be concentrated through evaporation beneath ephemeral streams and mobilized via irrigation or land use change. This study seeks to use extensive geochemical analyses of groundwater and surface water to differentiate between various sources of NO3 contamination. The U.S. Geological Survey collected 54 groundwater samples from wells and six samples from ephemeral streams from within and from outside of areas of known nitrate contamination. To fingerprint the sources of nitrate pollution, samples were analyzed for major ions, trace metals, nutrients, dissolved gases, δ15N and δ18O in NO3, δ15N within N2 gas, and, δ2H and δ18O in H2O. Furthermore, most sites were sampled for artificial sweeteners and numerous contaminants of emerging concern including pharmaceutical drugs, caffeine, and wastewater indicators. This study will also investigate the age distribution of groundwater and the approximate age of anthropogenic NO3 contamination using 3He/4He, δ13C, 14C, 3H, as well as pharmaceutical drugs and artificial sweeteners with known patent and U.S. Food and Drug Administration approval dates. This broad suite of analytes will be used to differentiate between naturally occurring and multiple anthropogenic NO3 sources, and to potentially determine the approximate date of NO3 contamination.
Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Kärki, Janne
2015-02-01
This is the third and final part of the three-part article written to describe the mass, energy and material balances of the solid recovered fuel production process produced from various types of waste streams through mechanical treatment. This article focused the production of solid recovered fuel from municipal solid waste. The stream of municipal solid waste used here as an input waste material to produce solid recovered fuel is energy waste collected from households of municipality. This article presents the mass, energy and material balances of the solid recovered fuel production process. These balances are based on the proximate as well as the ultimate analysis and the composition determination of various streams of material produced in a solid recovered fuel production plant. All the process streams are sampled and treated according to CEN standard methods for solid recovered fuel. The results of the mass balance of the solid recovered fuel production process showed that 72% of the input waste material was recovered in the form of solid recovered fuel; 2.6% as ferrous metal, 0.4% as non-ferrous metal, 11% was sorted as rejects material, 12% as fine faction and 2% as heavy fraction. The energy balance of the solid recovered fuel production process showed that 86% of the total input energy content of input waste material was recovered in the form of solid recovered fuel. The remaining percentage (14%) of the input energy was split into the streams of reject material, fine fraction and heavy fraction. The material balances of this process showed that mass fraction of paper and cardboard, plastic (soft) and wood recovered in the solid recovered fuel stream was 88%, 85% and 90%, respectively, of their input mass. A high mass fraction of rubber material, plastic (PVC-plastic) and inert (stone/rock and glass particles) was found in the reject material stream. © The Author(s) 2014.
Ambient groundwater flow diminishes nitrate processing in the hyporheic zone of streams
NASA Astrophysics Data System (ADS)
Azizian, Morvarid; Boano, Fulvio; Cook, Perran L. M.; Detwiler, Russell L.; Rippy, Megan A.; Grant, Stanley B.
2017-05-01
Modeling and experimental studies demonstrate that ambient groundwater reduces hyporheic exchange, but the implications of this observation for stream N-cycling is not yet clear. Here we utilize a simple process-based model (the Pumping and Streamline Segregation or PASS model) to evaluate N-cycling over two scales of hyporheic exchange (fluvial ripples and riffle-pool sequences), ten ambient groundwater and stream flow scenarios (five gaining and losing conditions and two stream discharges), and three biogeochemical settings (identified based on a principal component analysis of previously published measurements in streams throughout the United States). Model-data comparisons indicate that our model provides realistic estimates for direct denitrification of stream nitrate, but overpredicts nitrification and coupled nitrification-denitrification. Riffle-pool sequences are responsible for most of the N-processing, despite the fact that fluvial ripples generate 3-11 times more hyporheic exchange flux. Across all scenarios, hyporheic exchange flux and the Damköhler Number emerge as primary controls on stream N-cycling; the former regulates trafficking of nutrients and oxygen across the sediment-water interface, while the latter quantifies the relative rates of organic carbon mineralization and advective transport in streambed sediments. Vertical groundwater flux modulates both of these master variables in ways that tend to diminish stream N-cycling. Thus, anthropogenic perturbations of ambient groundwater flows (e.g., by urbanization, agricultural activities, groundwater mining, and/or climate change) may compromise some of the key ecosystem services provided by streams.
Method for the removal of ultrafine particulates from an aqueous suspension
Chaiko, David J.; Kopasz, John P.; Ellison, Adam J. G.
2000-01-01
A method of separating ultra-fine particulates from an aqueous suspension such as a process stream or a waste stream. The method involves the addition of alkali silicate and an organic gelling agent to a volume of liquid, from the respective process or waste stream, to form a gel. The gel then undergoes syneresis to remove water and soluble salts from the gel containing the particulates, thus, forming a silica monolith. The silica monolith is then sintered to form a hard, nonporous waste form.
Method for the Removal of Ultrafine Particulates from an Aqueous Suspension
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chaiko, David J.; Kopasz, John P.; Ellison, Adam J.G.
1999-03-05
A method of separating ultra-fine particulate from an aqueous suspension such as a process stream or a waste stream. The method involves the addition of alkali silicate and an organic gelling agent to a volume of liquid, from the respective process or waste stream, to form a gel. The gel then undergoes syneresis to remove water and soluble salts from the gel-containing the particulate, thus, forming a silica monolith. The silica monolith is then sintered to form a hard, nonporous waste form.
Process of forming catalytic surfaces for wet oxidation reactions
NASA Technical Reports Server (NTRS)
Jagow, R. B. (Inventor)
1977-01-01
A wet oxidation process was developed for oxidizing waste materials, comprising dissolved ruthenium salt in a reactant feed stream containing the waste materials. The feed stream is introduced into a reactor, and the reactor contents are then raised to an elevated temperature to effect deposition of a catalytic surface of ruthenium black on the interior walls of the reactor. The feed stream is then maintained in the reactor for a period of time sufficient to effect at least partial oxidation of the waste materials.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Information for Waste Management Units... Subpart G of Part 63—Information for Waste Management Units To Be Submitted With Notification of Compliance Status a,b Waste management unit identification c Description d Wastewater stream(s) received or...
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Information for Waste Management Units... Subpart G of Part 63—Information for Waste Management Units To Be Submitted With Notification of Compliance Status a,b Waste management unit identification c Description d Wastewater stream(s) received or...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Information for Waste Management Units... Subpart G of Part 63—Information for Waste Management Units To Be Submitted With Notification of Compliance Status a,b Waste management unit identification c Description d Wastewater stream(s) received or...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Information for Waste Management Units... Subpart G of Part 63—Information for Waste Management Units To Be Submitted With Notification of Compliance Status a,b Waste management unit identification c Description d Wastewater stream(s) received or...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Information for Waste Management Units... Subpart G of Part 63—Information for Waste Management Units To Be Submitted With Notification of Compliance Status a b Waste management unit identification c Description d Wastewater stream(s) received or...
40 CFR 63.1082 - What definitions do I need to know?
Code of Federal Regulations, 2011 CFR
2011-07-01
... includes direct-contact cooling water. Spent caustic waste stream means the continuously flowing process... compounds from process streams, typically cracked gas. The spent caustic waste stream does not include spent..., and the C4 butadiene storage equipment; and spent wash water from the C4 crude butadiene carbonyl wash...
40 CFR 63.1082 - What definitions do I need to know?
Code of Federal Regulations, 2012 CFR
2012-07-01
... includes direct-contact cooling water. Spent caustic waste stream means the continuously flowing process... compounds from process streams, typically cracked gas. The spent caustic waste stream does not include spent..., and the C4 butadiene storage equipment; and spent wash water from the C4 crude butadiene carbonyl wash...
40 CFR 63.1082 - What definitions do I need to know?
Code of Federal Regulations, 2014 CFR
2014-07-01
... includes direct-contact cooling water. Spent caustic waste stream means the continuously flowing process... compounds from process streams, typically cracked gas. The spent caustic waste stream does not include spent..., and the C4 butadiene storage equipment; and spent wash water from the C4 crude butadiene carbonyl wash...
40 CFR 63.1082 - What definitions do I need to know?
Code of Federal Regulations, 2013 CFR
2013-07-01
... includes direct-contact cooling water. Spent caustic waste stream means the continuously flowing process... compounds from process streams, typically cracked gas. The spent caustic waste stream does not include spent..., and the C4 butadiene storage equipment; and spent wash water from the C4 crude butadiene carbonyl wash...
Effects of agriculture production systems on nitrate and nitrite accumulation on baby-leaf salads
Aires, Alfredo; Carvalho, Rosa; Rosa, Eduardo A S; Saavedra, Maria J
2013-01-01
Nitrate and nitrite are widespread contaminants of vegetables, fruits, and waters. The levels of these compounds are increased as a result of using organic wastes from chemical industries, domestic wastes, effluents, nitrogenous fertilizers, and herbicides in agriculture. Therefore, determining the nitrate and nitrite levels in biological, food, and environmental samples is important to protect human health and the environment. In this context, we set this study, in which we report the effect of production system (conventional and organic) on the accumulation of nitrates and nitrites in fresh baby-leaf samples. The average levels of the nitrate () and nitrite () contents in six different baby-leaf salads of a single species (green lettuce, red lettuce, watercress, rucola, chard, and corn salad) produced in organic and conventional agriculture system were evaluated. Spectrophotometric analytical method recently published was validated and used. Nitrates and nitrites were detected in all samples. The nitrates levels from organic production varied between 1.45 and 6.40 mg/kg fresh weight (FW), whereas those from conventional production ranged from 10.5 to 45.19 mg/kg FW. The nitrites content was lower than nitrates and ranged from 0.32 to 1.89 mg/kg FW in organic production system and between 0.14 and 1.41 mg/kg FW in conventional production system. Our results showed that the nitrate content was dependent on the agricultural production system, while for nitrites, this dependency was less pronounced. PMID:24804008
Canyon transfer neutron absorber to fissile material ratio analysis. Revision 1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clemmons, J.S.
1994-03-04
Waste tank fissile material and non-fissile material estimates are used to evaluate criticality safety for the existing sludge inventory and batches of sludge sent to Extended Sludge Processing (ESP). This report documents the weight ratios of several non-fissile waste constituents to fissile waste constituents from canyon reprocessing waste streams. Weight ratios of Fe, Mn, Al, Mi, and U-238 to fissile material are calculated from monthly loss estimates from the F and H Canyon Low Heat Waste (LHW) and High Heat Waste (HHW) streams. The monthly weight ratios for Fe, Mn and U-238 are then compared to calculated minimum safe weightmore » ratios. Documented minimum safe weight ratios for Al and Ni to fissile material are currently not available. Total mass data for the subject sludge constituents is provided along with scatter plots of the monthly weight ratios for each waste stream.« less
Bergquist, Allison M; Choe, Jong Kwon; Strathmann, Timothy J; Werth, Charles J
2016-06-01
Ion exchange (IX) is the most common approach to treating nitrate-contaminated drinking water sources, but the cost of salt to make regeneration brine, as well as the cost and environmental burden of waste brine disposal, are major disadvantages. A hybrid ion exchange-catalyst treatment system, in which waste brine is catalytically treated for reuse, shows promise for reducing costs and environmental burdens of the conventional IX system. An IX model with separate treatment and regeneration cycles was developed, and ion selectivity coefficients for each cycle were separately calibrated by fitting experimental data. Of note, selectivity coefficients for the regeneration cycle required fitting the second treatment cycle after incomplete resin regeneration. The calibrated and validated model was used to simulate many cycles of treatment and regeneration using the hybrid system. Simulated waste brines and a real brine obtained from a California utility were also evaluated for catalytic nitrate treatment in a packed-bed, flow-through column with 0.5 wt%Pd-0.05 wt%In/activated carbon support (PdIn/AC). Consistent nitrate removal and no apparent catalyst deactivation were observed over 23 d (synthetic brine) and 45 d (real waste brine) of continuous-flow treatment. Ion exchange and catalyst results were used to evaluate treatment of 1 billion gallons of nitrate-contaminated source water at a 0.5 MGD water treatment plant. Switching from a conventional IX system with a two bed volume regeneration to a hybrid system with the same regeneration length and sequencing batch catalytic reactor treatment would save 76% in salt cost. The results suggest the hybrid system has the potential to address the disadvantages of a conventional IX treatment systems. Copyright © 2016 Elsevier Ltd. All rights reserved.
Tracing the Fate of Atmospheric Nitrate in a Subalpine Watershed Using Δ17O.
Bourgeois, Ilann; Savarino, Joël; Caillon, Nicolas; Angot, Hélène; Barbero, Albane; Delbart, Franck; Voisin, Didier; Clément, Jean-Christophe
2018-05-15
Nitrogen is an essential nutrient for life on Earth, but in excess, it can lead to environmental issues (e.g., N saturation, loss of biodiversity, acidification of lakes, etc.). Understanding the nitrogen budget (i.e., inputs and outputs) is essential to evaluate the prospective decay of the ecosystem services (e.g., freshwater quality, erosion control, loss of high patrimonial-value plant species, etc.) that subalpine headwater catchments provide, especially as these ecosystems experience high atmospheric nitrogen deposition. Here, we use a multi-isotopic tracer (Δ 17 O, δ 15 N and δ 18 O) of nitrate in aerosols, snow, and streams to assess the fate of atmospherically deposited nitrate in the subalpine watershed of the Lautaret Pass (French Alps). We show that atmospheric N deposition contributes significantly to stream nitrate pool year-round, either by direct inputs (up to 35%) or by in situ nitrification of atmospheric ammonium (up to 35%). Snowmelt in particular leads to high exports of atmospheric nitrate, most likely fast enough to impede assimilation by surrounding ecosystems. Yet, in a context of climate change, with shorter snow seasons, and increasing nitrogen emissions, our results hint at possibly stronger ecological consequences of nitrogen atmospheric deposition in the close future.
30 CFR 56.6309 - Fuel oil requirements for ANFO.
Code of Federal Regulations, 2013 CFR
2013-07-01
... that of No. 2 diesel oil (125 °F) shall not be used to prepare ammonium nitrate-fuel oil, except that.... (b) Waste oil, including crankcase oil, shall not be used to prepare ammonium nitrate-fuel oil. ...
30 CFR 56.6309 - Fuel oil requirements for ANFO.
Code of Federal Regulations, 2014 CFR
2014-07-01
... that of No. 2 diesel oil (125 °F) shall not be used to prepare ammonium nitrate-fuel oil, except that.... (b) Waste oil, including crankcase oil, shall not be used to prepare ammonium nitrate-fuel oil. ...
30 CFR 56.6309 - Fuel oil requirements for ANFO.
Code of Federal Regulations, 2012 CFR
2012-07-01
... that of No. 2 diesel oil (125 °F) shall not be used to prepare ammonium nitrate-fuel oil, except that.... (b) Waste oil, including crankcase oil, shall not be used to prepare ammonium nitrate-fuel oil. ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCabe, Daniel J.; Nash, Charles A.; Adamson, Duane J.
The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Melter Off-Gas Condensate, LMOGC) from the off-gas system. The baseline plan for disposition of this stream during full WTP operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. However, during the Direct Feed LAW (DFLAW) scenario, planned disposition of this stream is to evaporate it in a new evaporator in the Effluent Management Facility (EMF) and then return it tomore » the LAW melter. It is important to understand the composition of the effluents from the melter and new evaporator so that the disposition of these streams can be accurately planned and accommodated. Furthermore, alternate disposition of the LMOGC stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Alternate disposition would also eliminate this stream from recycling within WTP when it begins operations and would decrease the LAW vitrification mission duration and quantity of glass waste, amongst the other problems such a recycle stream present. This LAW Melter Off-Gas Condensate stream will contain components that are volatile at melter temperatures and are problematic for the glass waste form, such as halides and sulfate. Because this stream will recycle within WTP, these components accumulate in the Melter Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Diverting the stream reduces the halides and sulfate in the recycled Condensate and is a key outcome of this work. This overall program examines the potential treatment and immobilization of this stream to enable alternative disposal. The objective of this task was to formulate and prepare a simulant of the LAW Melter Off-gas Condensate expected during DFLAW operations. That simulant can be used in evaporator testing to predict the composition of the effluents from the Effluent Management Facility (EMF) evaporator to aid in planning for their disposition. This document describes the method used to formulate a simulant of this LAW Melter Off-Gas Condensate stream, which, after pH adjustment, is the feed to the evaporator in the EMF.« less
Hydrological control over stream nitrate loss in an aggrading New Hampshire forest
NASA Astrophysics Data System (ADS)
Daley, R.; Goodale, C. L.; Buso, D.; Driscoll, C. T.; Fuss, C.; Likens, G. E.
2008-12-01
Stream chemistry of a small watershed in the Hubbard Brook Experimental Forest (Watershed 4) displays higher nitrate export than expected for an early successional forest in this region. Within Watershed 4, a small tributary (300 m in length) has a chemical signature far different from the main channel (1000 m in length). Previous monitoring has shown that the pH of the side tributary was significantly higher than that of the main channel and contains detectable levels of nitrate whereas the main channel had no detectable nitrate, and it is suspected that this side tributary significantly contributes to watershed export under base flow conditions. We expected that watershed's dominant water and chemical sources would vary with flow conditions, especially during summer thunderstorms. We hypothesized that the side tributary is the dominant source area under the normal base flow conditions of the summer (usually under 1 L/s) and that the main stem exerts dominance under the high flow conditions brought on by events. Daily water samples were taken throughout summer 2008 with three ISCO automated samplers: One ISCO was placed at the main stem of the stream, a second at the small internal tributary, and a third was placed at the weir. The samples were analyzed for pH, specific conductivity, and ANC, DOC, DON, and major anions and cations. The chemical data was compared to precipitation and rate of watershed flow calculated at each sampling hour to detect associations between chemical dominance and hydrological conditions. Under the base flow conditions of the summer, the chemistry of watershed outflow was dominated by that of the short side tributary, with lower acidity and higher nitrate levels than the longer main channel, but with notable contributions from the main channel. During each of the three high flow events that occurred over the summer, flow in the main channel increased dramatically and flow at the weir corresponded to temporarily increased acidity and decreased ANC. Preliminary nitrate data shows that a dilution response was associated with these events since there were significant declines in the nitrate levels of both the side tributary and watershed export during high flow conditions.
Devasya, Roopa; Bassi, Amarjeet
2017-11-15
Phyco-remediation is an environmental-friendly method, which involves the application of beneficial microalgae to treat wastewater-containing pollutants for a diverse range of conditions. Several industrial processes generate hyper saline wastewater, which is a significant challenge for conventional wastewater treatment, and the disposal of saline waters also has a negative impact on the environment. Road salt run-off is one such saline wastewater stream not currently treated and one that contributes significantly to negatively impacting receiving bodies of water. In this study, Nannochloropsis microalgae were able to assimilate >95% of the nitrates within 8 days in road salt concentrations ranging from 2.6% to 4.4% under phototrophic cultivation mode. Biomass yields of 1-2 g/l of culture were obtained with the maximum lipid of 22% (g/g) biomass in the road salt media. The crude road salt media provided all the essential micronutrients needed for algal cultivation. The fatty acid composition analysis of the obtained lipid composed of C16 and C18 over 45% of FAME are suitable for biofuel. This study has established that the use of road salt containing nitrate and phosphate nutrients will support the growth of marine micro algae for remediation of a waste water system that are the concern at winter-prevalent regions.
Nitrogen-isotope ratios of nitrate in ground water under fertilized fields, Long Island, New York
Flipse, W.J.; Bonner, F.T.
1985-01-01
Ground-water samples from two heavily fertilized sites in Suffolk County, New York, were collected through the 1978 growing season and analyzed for nitrate-N concentrations and nitrogen-isotope ratios. Six wells were at a potato farm; six were on a golf course. The purpose of this study was to determine whether the 15N/14N ratios (??15N values) of fertilizer are increased during transit from land surface to ground water to an extent which would preclude use of this ratio to distinguish agricultural from animal sources of nitrate in ground water. Ground water at both sites contained a greater proportion of 15N than the fertilizers being applied. At the potato farm, the average ??15N value of the fertilizers was 0.2???; the average ??15N value of the ground-water nitrate was 6.2???. At the golf course, the average ??15N value of the fertilizers was -5.9???, and that of ground-water nitrate was 6.5???. The higher ??15N values of ground-water nitrate are probably caused by isotopic fractionation during the volatile loss of ammonia from nitrogen applied in reduced forms (NH4+ and organic-N). The ??15N values of most ground-water samples from both areas were less than 10???, the upper limit of the range characteristic of agricultural sources of nitrate; these sources include both fertilizer nitrate and nitrate derived from increased mineralization of soil nitrogen through cultivation. Previous studies have shown that the ??15N values of nitrate derived from human or animal waste generally exceed 10???. The nitrogen-isotope ratios of fertilizer-derived nitrate were not altered to an extent that would make them indistinguishable from animal-waste-derived nitrates in ground water.Ground-water samples from two heavily fertilized sites in Suffolk County, New York, were collected through the 1978 growing season and analyzed for nitrate-N concentrations and nitrogen-isotope ratios. Six wells were at a potato farm; six were on a golf course. The purpose of this study was to determine whether the **1**5N/**1**4N ratios ( delta **1**5N values) of fertilizer are increased during transit from land surface to ground water to an extent which would preclude use of this ratio to distinguish agricultural from animal sources of nitrate in ground water. Ground water at both sites contained a greater proportion of **1**5N than the fertilizers being applied. The nitrogen-isotope ratios of fertilizer-derived nitrate were not altered to an extent that would make them indistinguishable from animal-waste-derived nitrates in ground water.
Rating curve estimation of nutrient loads in Iowa rivers
Stenback, G.A.; Crumpton, W.G.; Schilling, K.E.; Helmers, M.J.
2011-01-01
Accurate estimation of nutrient loads in rivers and streams is critical for many applications including determination of sources of nutrient loads in watersheds, evaluating long-term trends in loads, and estimating loading to downstream waterbodies. Since in many cases nutrient concentrations are measured on a weekly or monthly frequency, there is a need to estimate concentration and loads during periods when no data is available. The objectives of this study were to: (i) document the performance of a multiple regression model to predict loads of nitrate and total phosphorus (TP) in Iowa rivers and streams; (ii) determine whether there is any systematic bias in the load prediction estimates for nitrate and TP; and (iii) evaluate streamflow and concentration factors that could affect the load prediction efficiency. A commonly cited rating curve regression is utilized to estimate riverine nitrate and TP loads for rivers in Iowa with watershed areas ranging from 17.4 to over 34,600km2. Forty-nine nitrate and 44 TP datasets each comprising 5-22years of approximately weekly to monthly concentrations were examined. Three nitrate data sets had sample collection frequencies averaging about three samples per week. The accuracy and precision of annual and long term riverine load prediction was assessed by direct comparison of rating curve load predictions with observed daily loads. Significant positive bias of annual and long term nitrate loads was detected. Long term rating curve nitrate load predictions exceeded observed loads by 25% or more at 33% of the 49 measurement sites. No bias was found for TP load prediction although 15% of the 44 cases either underestimated or overestimate observed long-term loads by more than 25%. The rating curve was found to poorly characterize nitrate and phosphorus variation in some rivers. ?? 2010 .
We established two study sites with similar soils and hydrology but contrasting riparian vegetation along Lake Creek, an intermittent stream that drains perennial ryegrass fields in the Willamette Valley of western Oregon. One site had a non-cultivated riparian zone with a plant...
ESTIMATION OF TOTAL DISSOLVED NITRATE LOAD IN NATURAL STREAM FLOWS USING AN IN-STREAM MONITOR
Estuaries respond rapidly to rain events and the nutrients carried by inflowing rivers such that discrete samples at weekly or monthly intervals are inadequate to catch the maxima and minima in nutrient variability. To acquire data with sufficient sampling frequency to realistica...
Clune, John W.; Denver, Judith M.
2012-01-01
Nitrate is a common contaminant in groundwater and surface water throughout the Nation, and water-resource managers need more detailed small-scale watershed research to guide conservation efforts aimed at improving water quality. Concentrations of nitrate in Bucks Branch are among the highest in the state of Delaware and a scientific investigation was performed to provide water-quality information to assist with the management of agriculture and water resources. A combination of major-ion chemistry, nitrogen isotopic composition and age-dating techniques was used to estimate the residence time and provide a chemical and isotopic analysis of nitrate in the groundwater in the surficial aquifer of the Bucks Branch watershed in Sussex County, Delaware. The land use was more than 90 percent agricultural and most nitrogen inputs were from manure and fertilizer. The apparent median age of sampled groundwater is 18 years and the estimated residence time of groundwater contributing to the streamflow for the entire Bucks Branch watershed at the outlet is approximately 19 years. Concentrations of nitrate exceeded the U.S. Environmental Protection Agency drinking-water standard of 10 milligrams per liter (as nitrogen) in 60 percent of groundwater samples and 42 percent of surface-water samples. The overall geochemistry in the Bucks Branch watershed indicates that agriculture is the predominant source of nitrate contamination and the observed patterns in major-ion chemistry are similar to those observed in other studies on the Mid-Atlantic Coastal Plain. The pattern of enrichment in nitrogen and oxygen isotopes (δ15N and δ18O) of nitrate in groundwater and surface water indicates there is some loss of nitrate through denitrification, but this process is not sufficient to remove all of the nitrate from groundwater discharging to streams, and concentrations of nitrate in streams remain elevated.
Peters, James G.; Wilber, W.G.; Crawford, Charles G.; Girardi, F.P.
1979-01-01
A digital computer model calibrated to observe stream conditions was used to evaluate water quality in West Fork Blue River, Washington County, IN. Instream dissolved-oxygen concentration averaged 96.5% of saturation at selected sites on West Fork Blue River during two 24-hour summer surveys. This high dissolved-oxygen concentration reflects small carbonaceous and nitrogenous waste loads; adequate dilution of waste by the stream; and natural reaeration. Nonpoint source waste loads accounted for an average of 53.2% of the total carbonaceous biochemical-oxygen demand and 90.2% of the nitrogenous biochemical-oxygen demand. Waste-load assimilation was studiedfor critical summer and winter low flows. Natural streamflow for these conditions was zero, so no benefit from dilution was provided. The projected stream reaeration capacity was not sufficient to maintain the minimum daily dissolved-oxygen concentration (5 milligrams per liter) in the stream with current waste-discharge restrictions. During winter low flow, ammonia toxicity, rather than dissolved-oxygen concentration, was the limiting water-quality criterion downstream from the Salem wastewater-treatment facility. (USGS)
Infrared Mass Spectrometry for Environmental and Biomedical Applications
NASA Astrophysics Data System (ADS)
Baltz-Knorr, M. L.; Papantonakis, M. R.; Ermer Haglund, D. R., Jr.
2000-11-01
Matrix-assisted laser desorption and ionization (MALDI) mass spectrometry (MS) using a tunable, ultrashort pulse, mid-infrared free electron laser (FEL) has many applications for both environmental and biomedical research. Environmentally, the characterization of stored nuclear materials has been an important area of research. We are developing a method to determine nuclear tank waste constituents using MALDI MS. This includes desorption and ionization of small organic molecules from sodium nitrate solids and slurries (similar to the salt cake found in some tanks) and also from traditional MALDI matrices. Important aspects of the technique are that it does not produce a secondary waste stream and it is potentially field-deployable using solid-state lasers. Biomedically, the ability to do proteomics is being enhanced by the sensitivity and mass accuracy provided by MALDI MS. We are using MALDI MS to identify proteins embedded in liquid matrix materials, which provide a more natural environment for the biomolecules. We are also working on coupling MALDI MS to traditional protein identification and sequencing techniques for rapid analysis of large numbers of proteins. Research supported by the Office of Naval Research and the U.S. Department of Energy
Investigation of new hypergol scrubber technology
NASA Technical Reports Server (NTRS)
Glasscock, Barbara H.
1994-01-01
The ultimate goal of this work is to minimize the liquid waste generated from the scrubbing of hypergolic vent gases. In particular, nitrogen tetroxide, a strong oxidizer used in hypergolic propellant systems, is currently scrubbed with a sodium hydroxide solution resulting in a hazardous liquid waste. This study investigated the use of a solution of potassium hydroxide and hydrogen peroxide for the nitrogen textroxide vent scrubber system. The potassium nitrate formed would be potentially usable as a fertilizer. The hydrogen peroxide is added to convert the potassium nitrite that is formed into more potassium nitrate. Smallscale laboratory tests were conducted to establish the stability of hydrogen peroxide in the proposed scrubbing solution and to evaluate the effectiveness of hydrogen peroxide in converting nitrite to nitrate.
Development of Acetic Acid Removal Technology for the UREX+Process
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robert M. Counce; Jack S. Watson
2009-06-30
It is imperative that acetic acid is removed from a waste stream in the UREX+process so that nitric acid can be recycled and possible interference with downstreatm steps can be avoidec. Acetic acid arises from acetohydrozamic acid (AHA), and is used to suppress plutonium in the first step of the UREX+process. Later, it is hydrolyzed into hydroxyl amine nitrate and acetic acid. Many common separation technologies were examined, and solvent extraction was determined to be the best choice under process conditions. Solvents already used in the UREX+ process were then tested to determine if they would be sufficient for themore » removal of acetic acid. The tributyl phosphage (TBP)-dodecane diluent, used in both UREX and NPEX, was determined to be a solvent system that gave sufficient distribution coefficients for acetic acid in addition to a high separation factor from nitric acid.« less
Analysis and interpretation of water-quality trends in major U.S. rivers, 1974-81
Smith, Richard A.; Alexander, Richard B.; Wolman, M. Gordon
1987-01-01
Water-quality records from two nationwide sampling networks are now of sufficient length to permit nationally consistent analysis of long-term water-quality trends at more than 300 locations on major U.S. rivers. Observed trends in 24 water-quality measures for the period 1974--81 provide evidence of both improvement and deterioration in stream quality during a time of major changes in atmospheric and terrestrial influences on surface waters. Particularly noteworthy are widespread decreases in lead and fecal bacteria concentrations and widespread increases in nitrate, arsenic, and cadmium concentrations. Changes in municipal waste treatment, leaded-gasoline consumption, highway-salt use, and nitrogen-fertilizer application, and regionally variable trends in coal production and combustion during the period, appear to be reflected in water-quality changes. There is evidence that atmospheric deposition of a variety of substances has played a surprisingly large role in water-quality changes.
Stabilization and Solidification of Nitric Acid Effluent Waste at Y-12
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singh, Dileep; Lorenzo-Martin, Cinta
Consolidated Nuclear Security, LLC (CNS) at the Y-12 plant is investigating approaches for the treatment (stabilization and solidification) of a nitric acid waste effluent that contains uranium. Because the pH of the waste stream is 1-2, it is a difficult waste stream to treat and stabilize by a standard cement-based process. Alternative waste forms are being considered. In this regard, Ceramicrete technology, developed at Argonne National Laboratory, is being explored as an option to solidify and stabilize the nitric acid effluent wastes.
Code of Federal Regulations, 2014 CFR
2014-07-01
... PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORGANIC CHEMICALS, PLASTICS, AND SYNTHETIC... Picolines, mixed/Condensation of acetaldehyde + formaldehyde + ammonia Organic pigments, Azo/Diazotization...
Code of Federal Regulations, 2011 CFR
2011-07-01
... PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORGANIC CHEMICALS, PLASTICS, AND SYNTHETIC... Picolines, mixed/Condensation of acetaldehyde + formaldehyde + ammonia Organic pigments, Azo/Diazotization...
Code of Federal Regulations, 2013 CFR
2013-07-01
... PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORGANIC CHEMICALS, PLASTICS, AND SYNTHETIC... Picolines, mixed/Condensation of acetaldehyde + formaldehyde + ammonia Organic pigments, Azo/Diazotization...
Code of Federal Regulations, 2012 CFR
2012-07-01
... PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORGANIC CHEMICALS, PLASTICS, AND SYNTHETIC... Picolines, mixed/Condensation of acetaldehyde + formaldehyde + ammonia Organic pigments, Azo/Diazotization...
USDA-ARS?s Scientific Manuscript database
Grids of perforated pipe buried beneath many poorly drained agricultural fields in the Midwestern U.S. are believed to “short circuit” pools of nitrate-laden soil water and shallow groundwater directly into streams that eventually discharge to the Mississippi River. Although much is known about the ...
Evaluation of Nitrate Sources and Nitrate Management Strategies in California Suburban Growth Areas
NASA Astrophysics Data System (ADS)
Singleton, M. J.; Moran, J. E.; Esser, B. K.; Leif, R. N.; McNab, W. W.; Carle, S. F.; Moore, K. B.
2005-12-01
Population growth in California has pushed the boundaries of suburban communities into formerly agricultural areas. As a result there is considerable uncertainty as to whether nitrate contamination in groundwater wells results from current sources or is a legacy of agriculture. Fertilizer application for historical agriculture is frequently assumed to be a major source, but septic system leachate, other animal waste, and residential fertilizer application may also contribute. Potential remediation strategies may include improved fertilizer management and/or conversion from septic tanks to sewer systems, but the sources of nitrate and pathways to groundwater must first be identified in order to develop a plan of action. We combine the detection of trace organic compounds that are specific to domestic waste with isotopic compositions of nitrogen and oxygen in nitrate in order to determine nitrate sources. Under anaerobic conditions and in the presence of an electron donor such as organic carbon, microbially mediated denitrification may transform nitrate to harmless nitrogen gas, and fractionate the isotopologues of any residual nitrate. The occurrence of saturated zone denitrification is detected by measuring excess dissolved nitrogen gas with a field-portable membrane inlet mass spectrometer system. Groundwater age dating using the 3H/3He method provides a means of tracking the history of nitrate inputs to groundwater, including changes in nitrate flux after implementation of a remediation program. Groundwater that pre-dates agricultural or suburban activity is used to define natural background levels of nitrate. Study areas in California include Chico, Livermore, and Gilroy. This work was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.
Toward zero waste events: Reducing contamination in waste streams with volunteer assistance.
Zelenika, Ivana; Moreau, Tara; Zhao, Jiaying
2018-06-01
Public festivals and events generate a tremendous amount of waste, especially when they involve food and drink. To reduce contamination across waste streams, we evaluated three types of interventions at a public event. In a randomized control trial, we examined the impact of volunteer staff assistance, bin tops, and sample 3D items with bin tops, on the amount of contamination and the weight of the organics, recyclable containers, paper, and garbage bins at a public event. The event was the annual Apple Festival held at the University of British Columbia, which was attended by around 10,000 visitors. We found that contamination was the lowest in the volunteer staff condition among all conditions. Specifically, volunteer staff reduced contamination by 96.1% on average in the organics bin, 96.9% in the recyclable containers bin, 97.0% in the paper bin, and 84.9% in the garbage bin. Our interventions did not influence the weight of the materials in the bins. This finding highlights the impact of volunteers on reducing contamination in waste streams at events, and provides suggestions and implications for waste management for event organizers to minimize contamination in all waste streams to achieve zero waste goals. Copyright © 2018. Published by Elsevier Ltd.
Impact of sampling strategy on stream load estimates in till landscape of the Midwest
Vidon, P.; Hubbard, L.E.; Soyeux, E.
2009-01-01
Accurately estimating various solute loads in streams during storms is critical to accurately determine maximum daily loads for regulatory purposes. This study investigates the impact of sampling strategy on solute load estimates in streams in the US Midwest. Three different solute types (nitrate, magnesium, and dissolved organic carbon (DOC)) and three sampling strategies are assessed. Regardless of the method, the average error on nitrate loads is higher than for magnesium or DOC loads, and all three methods generally underestimate DOC loads and overestimate magnesium loads. Increasing sampling frequency only slightly improves the accuracy of solute load estimates but generally improves the precision of load calculations. This type of investigation is critical for water management and environmental assessment so error on solute load calculations can be taken into account by landscape managers, and sampling strategies optimized as a function of monitoring objectives. ?? 2008 Springer Science+Business Media B.V.
Fisher, Donald W.
1967-01-01
A 2-year study of precipitation composition over eastern North Carolina and southeastern Virginia has been completed. Chemical analyses were made of the major ions in monthly rainfall samples from each of 12 sampling locations. Areal and seasonal distributions were determined for chloride, calcium, magnesium, sodium, potassium, sulfate, and nitrate. Annual changes in loads and in geographical distribution of sulfate and of nitrate are small. Yearly rainfall sulfate loads amount to approximately 7 tons per square mile, whereas deposition of nitrate is about 2 tons per square mile per year in the interior of the network and less near the coast. Areal patterns of chloride content are consistent with the assumption that the ocean is the only major source of rainfall chloride in the area. Chloride loads were 2.1 and 1.8 tons per square mile per year; the difference can be attributed to meteorological conditions. Cation concentrations in network precipitation appear to depend on localized sources, probably soil dust. Annual loads of the major cations are approximately 2 tons per square mile of calcium, 1.8 tons per square mile of sodium, 0.5 ton per square mile of magnesium, and 0.3 ton per square mile of potassium; considerable year-to-year differences were noted in these values. Bicarbonate and hydrogen ion in network rainfall are closely related to the relative concentrations of sulfate and calcium. Apparently, reaction of an acidic sulfur-containing aerosol with an alkaline calcium source is one of the principal controls on precipitation alkalinity and pH. Ions in precipitation contribute substantially to the quality of surface water in the network area. Comparisons between precipitation input and stream export of ions for four North Carolina rivers show that rainfall sulfate is equal to sulfate discharged, whereas nitrate in rain slightly exceeds stream nitrate. Contributions of cations to the streams by way of precipitation range from about 20 percent for potassium to almost 50 percent for calcium. Chloride deposited by precipitation amounts to about one-fourth of the stream load. Additions of manufactured salt may account for much of the remainder of the surface-water load.
Domagalski, Joseph L.; Lin, Chao; Luo, Yang; Kang, Jie; Wang, Shaoming; Brown, Larry R.; Munn, Mark D.
2007-01-01
Concentrations, loads, and sources of nitrate and total phosphorus were investigated at the Panjiakou and Daheiting Reservoir system in northern Hebei Province, People's Republic of China. The Luan He River is the primary source of water to these reservoirs, and the upstream watershed has a mix of land uses including agriculture, forest, and one large urban center. The reservoirs have a primary use for storage of drinking water and partially supply Tianjin City with its annual needs. Secondary uses include flood control and aqua culture (fish cages). The response of the reservoir system from phosphorus input, with respect to chlorophyll-a production from algae, was fitted to a model of normalized phosphorus loading that regresses the average summer-time chlorophyll-a concentration to the average annual phosphorus concentration of the reservoir. Comparison of the normalized phosphorus loading and chlorophyll-a response of this system to other reservoirs throughout the world indicate a level of eutrophication that will require up to an approximate 5–10-fold decrease in annual phosphorus load to bring the system to a more acceptable level of algal productivity. Isotopes of nitrogen and oxygen in dissolved nitrate were measured from the headwater streams and at various locations along the major rivers that provide the majority of water to these reservoirs. Those isotopic measurements indicate that the sources of nitrate change from natural background in the rivers to animal manure and septic waste upstream of the reservoir. Although the isotopic measurements suggest that animal and septic wastes are a primary source of nutrients, measurements of the molar ratio of nitrogen to phosphorus are more indicative of row-cropping practices. Options for reduction of nutrient loads include changing the management practices of the aqua culture, installation of new sewage treatment systems in the large urbanized area of the upper watershed, and agricultural management practices that would reduce the loading of nutrients and soil erosion from that land use.
Larson, Danelle M.; Dodds, Walter K.; Veach, Allison M.
2018-04-23
Riparian zones are key interfaces between stream and terrestrial ecosystems. Yet, we know of no whole-watershed experiments that cut only woody vegetation in the riparian zone in an otherwise intact watershed to isolate the role of riparian zones on stream ecology. We removed all of the woody riparian vegetation (from 10- and 30-m-wide buffers in headwaters and main channels, respectively) for 5 km of stream in a single watershed while leaving the remainder of the grassland watershed un-impacted. We assessed water chemistry changes 3 years before and 3 years after riparian wood removal and in two neighboring control watersheds withmore » a before–after, control-impact design and analysis. Riparian woody removal caused 10–100-fold increases in mean stream water nitrate concentrations and pulses of high nitrate for 3 years thereafter. Other nutrients and total suspended solids increased 2–25 times for the 3 years of post-removal. In-stream rates of gross primary production, ecosystem respiration, and net ecosystem production had large treatment effect sizes but also high variance among samples. Past studies of whole-watershed deforestations showed similar water quality responses to our riparian deforestation. Riparian zones of grassland streams are sensitive to disturbance and likely impart relatively greater influence on stream structure and function than the upslope of the watershed. Finally, our results further emphasize the role of riparian zones in biogeochemically linking aquatic and terrestrial habitats.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Larson, Danelle M.; Dodds, Walter K.; Veach, Allison M.
Riparian zones are key interfaces between stream and terrestrial ecosystems. Yet, we know of no whole-watershed experiments that cut only woody vegetation in the riparian zone in an otherwise intact watershed to isolate the role of riparian zones on stream ecology. We removed all of the woody riparian vegetation (from 10- and 30-m-wide buffers in headwaters and main channels, respectively) for 5 km of stream in a single watershed while leaving the remainder of the grassland watershed un-impacted. We assessed water chemistry changes 3 years before and 3 years after riparian wood removal and in two neighboring control watersheds withmore » a before–after, control-impact design and analysis. Riparian woody removal caused 10–100-fold increases in mean stream water nitrate concentrations and pulses of high nitrate for 3 years thereafter. Other nutrients and total suspended solids increased 2–25 times for the 3 years of post-removal. In-stream rates of gross primary production, ecosystem respiration, and net ecosystem production had large treatment effect sizes but also high variance among samples. Past studies of whole-watershed deforestations showed similar water quality responses to our riparian deforestation. Riparian zones of grassland streams are sensitive to disturbance and likely impart relatively greater influence on stream structure and function than the upslope of the watershed. Finally, our results further emphasize the role of riparian zones in biogeochemically linking aquatic and terrestrial habitats.« less
Design of Remediation Actions for Nutrient Mitigation in the Hyporheic Zone
NASA Astrophysics Data System (ADS)
Morén, I.; Wörman, A.; Riml, J.
2017-11-01
Although hyporheic exchange has been shown to be of great importance for the overall water quality of streams, it is rarely considered quantitatively in stream remediation projects. A main driver of hyporheic exchange is the hydraulic head fluctuation along the streambed, which can be enhanced by modifications of the streambed topography. Here we present an analytical 2-D spectral subsurface flow model to estimate the hyporheic exchange associated with streambed topographies over a wide range of spatial scales; a model that was validated using tracer-test-results and measurements of hydraulic conductivity. Specifically, engineered steps in the stream were shown to induce a larger hyporheic exchange velocity and shorter hyporheic residence times compared to the observed topography in Tullstorps Brook, Sweden. Hyporheic properties were used to parameterize a longitudinal transport model that accounted for reactions in terms of first-order decay and instantaneous adsorption. Theoretical analyses of the mitigation effect for nitrate due to denitrification in the hyporheic zone show that there is a Damköhler number of the hyporheic zone, associated with several different stream geomorphologies, that optimizes nitrate mass removal on stream reach scale. This optimum can be limited by the available hydraulic head gradient given by the slope of the stream and the geological constraints of the streambed. The model illustrates the complex interactions between design strategies for nutrient mitigation, hyporheic flow patterns, and stream biogeochemistry and highlights the importance to diagnose a stream prior remediation, specifically to evaluate if remediation targets are transport or reaction controlled.
JPRS Report: Near East & South Asia.
1993-07-27
a month now, since they first heard of the stream of waste water from the NRC. The stream has succeeded in worrying many residents of the south...done as part of an attempt to clear away the fog surrounding the incident of the stream of waste water from the NRC. Its main message: the truth...of the Makhtesh from the ministry of environmental affairs. Unequivocal demands by the authority’s inspectors to halt the stream of water into the
Barnes, R.T.; Raymond, P.A.
2010-01-01
Studies have repeatedly shown that agricultural and urban areas export considerably more nitrogen to streams than forested counterparts, yet it is difficult to identify and quantify nitrogen sources to streams due to complications associated with terrestrial and in-stream biogeochemical processes. In this study, we used the isotopic composition of nitrate (??15N-NO3- and ??18O- NO3-) in conjunction with a simple numerical model to examine the spatial and temporal variability of nitrate (NO3-) export across a land-use gradient and how agricultural and urban development affects net removal mechanisms. In an effort to isolate the effects of land use, we chose small headwater systems in close proximity to each other, limiting the variation in geology, surficial materials, and climate between sites. The ??15N and ??18Oof stream NO 3- varied significantly between urban, agricultural, and forested watersheds, indicating that nitrogen sources are the primary determinant of the ??15N-NO3-, while the ??18O-NO3- was found to reflect biogeochemical processes. The greatest NO3- concentrations corresponded with the highest stream ??15N-NO3- values due to the enriched nature of two dominant anthropogenic sources, septic and manure, within the urban and agricultural watersheds, respectively. On average, net removal of the available NO3- pool within urban and agricultural catchments was estimated at 45%. The variation in the estimated net removal of NO3- from developed watersheds was related to both drainage area and the availability of organic carbon. The determination of differentiated isotopic land-use signatures and dominant seasonal mechanisms illustrates the usefulness of this approach in examining the sources and processing of excess nitrogen within headwater catchments. ?? 2010 by the Ecological Society of America.
NASA Astrophysics Data System (ADS)
Jones, Christopher S.; Wang, Bo; Schilling, Keith E.; Chan, Kung-sik
2017-06-01
Agricultural landscapes often leak inorganic nitrogen to the stream network, usually in the form of nitrate-nitrite (NOx-N), degrading downstream water quality on both the local and regional scales. While the spatial distribution of nitrate sources has been delineated in many watersheds, less is known about the complicated temporal dynamics that drive stream NOx-N because traditional methods of stream grab sampling are often conducted at a low frequency. Deployment of accurate real-time, continuous measurement devices that have been developed in recent years enables high-frequency sampling that provides detailed information on the concentration-discharge relation and the timing of NOx-N delivery to streams. We aggregated 15-min interval NOx-N and discharge data over a nine-year period into daily averages and then used robust statistical methods to identify how the discharge regime within an artificially-drained agricultural watershed reflected catchment hydrology and NOx-N delivery pathways. We then quantified how transport and supply limitations varied from year-to-year and how dependence of these limitations varied with climate, especially drought. Our results show NOx-N concentrations increased linearly with discharge up to an average "turning point" of 1.42 mm of area-normalized discharge, after which concentrations decline with increasing discharge. We estimate transport and supply limitations to govern 57 and 43 percent, respectively, of the NOx-N flux over the nine-year period. Drought effects on the NOx-N flux linger for multiple years and this is reflected in a greater tendency toward supply limitations in the three years following drought. How the turning point varies with climate may aid in prediction of NOx-N loading in future climate regimes.
Filling Gaps in Biogeochemical Understanding of Wildfire Effects on Watersheds and Water Quality
NASA Astrophysics Data System (ADS)
Rhoades, Charles; Covino, Timothy; Chow, Alex
2017-04-01
Large, high-severity wildfires alter the biogeochemical conditions that determine how watersheds retain and release nutrients and influence stream water quality. These effects are commonly expected to abate within a few years, but recent studies show that post-fire watershed changes can have persistent, but poorly-understood biogeochemical consequences. Owing to the increased frequency and extent of high-severity wildfires predicted for western North America, and the growing awareness of the links between wildfire and clean water supply, there is a need to address these knowledge gaps. For the past 15 years we have tracked stream nutrients, chemistry, temperature, and sediment after the 2002 Hayman Fire, the largest wildfire in Colorado history. Our earlier work showed that headwater catchments that experienced extensive, high-severity forest fires had elevated stream nitrate, temperature, and turbidity for five post-fire years. Recent sampling, conducted 13 and 14 years after the fire, found that turbidity had largely returned to pretreatment levels, but that stream nitrate remained an order of magnitude above pre-fire levels in catchments with extensive high-severity wildfire. Stream temperature and total dissolved nitrogen concentration also remained higher in those catchments compared to unburned streams. Decreased plant demand is the mechanism commonly credited for post-fire nutrient losses, though our current work is evaluating the implications of soil and stream nutrient uptake and supply on persistent nitrogen (N) export from severely-burned catchments. For example, we have measured higher total soil N and higher net N mineralization in severely-burned portions of the Hayman Fire compared to moderately or unburned areas, indicating that higher soil N supply may contribute to N losses from upland soils. Conversely, using a nutrient tracer approach we found reduced N uptake in burned streams, which suggests a switch from the N-limited conditions typical of pristine catchments. Low stream dissolved organic carbon (DOC) in severely-burned catchments suggests greater carbon limitation on in-stream biological activity. This is the likely result of organic matter losses during the wildfire compounded by low allochthonous inputs from uplands or riparian zones. We also find that catchments with severely-burned headwater reaches and sparse riparian vegetation have high stream nitrate. Our findings regarding soil N supply and in-stream N retention coupled with the persistent N losses from burned headwaters and exposed riparian zones help prioritize restoration efforts aimed at mitigating long-term water quality effects of severe wildfires.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adamson, Duane J.; Nash, Charles A.; McCabe, Daniel J.
2014-01-01
The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream, LAW Off-Gas Condensate, from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrificationmore » mission duration and quantity of canistered glass waste forms. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to be within acceptable concentration ranges in the LAW glass. Diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task examines the impact of potential future disposition of this stream in the Hanford tank farms, and investigates auxiliary evaporation to enable another disposition path. Unless an auxiliary evaporator is used, returning the stream to the tank farms would require evaporation in the 242-A evaporator. This stream is expected to be unusual because it will be very high in corrosive species that are volatile in the melter (chloride, fluoride, sulfur), will have high ammonia, and will contain carryover particulates of glass-former chemicals. These species have potential to cause corrosion of tanks and equipment, precipitation of solids, release of ammonia gas vapors, and scale in the tank farm evaporator. Routing this stream to the tank farms does not permanently divert it from recycling into the WTP, only temporarily stores it prior to reprocessing. Testing is normally performed to demonstrate acceptable conditions and limits for these compounds in wastes sent to the tank farms. The primary parameter of this phase of the test program was measuring the formation of solids during evaporation in order to assess the compatibility of the stream with the evaporator and transfer and storage equipment. The origin of this LAW Off-Gas Condensate stream will be the liquids from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW facility melter offgas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover. The soluble components are expected to be mostly sodium and ammonium salts of nitrate, chloride, and fluoride. This stream has not been generated yet, and, thus, the composition will not be available until the WTP begins operation, but a simulant has been produced based on models, calculations, and comparison with pilot-scale tests. This report discusses results of evaporation testing of the simulant. Two conditions were tested, one with the simulant at near neutral pH, and a second at alkaline pH. The neutral pH test is comparable to the conditions in the Hanford Effluent Treatment Facility (ETF) evaporator, although that evaporator operates at near atmospheric pressure and tests were done under vacuum. For the alkaline test, the target pH was based on the tank farm corrosion control program requirements, and the test protocol and equipment was comparable to that used for routine evaluation of feed compatibility studies for the 242-A evaporator. One of the radionuclides that is volatile in the melter and expected to be in high concentration in this LAW Off-Gas Condensate stream is Technetium-99 (99Tc). Technetium will not be removed from the aqueous waste in the Hanford WTP, and will primarily end up immobilized in the LAW glass by repeated recycle of the off-gas condensate into the LAW melter. Other radionuclides that are also expected to be in appreciable concentrations in the LAW Off-Gas Condensate are 129I, 90Sr, 137Cs, and 241Am. The concentrations of these radionuclides in this stream will be much lower than in the LAW, but they will still be higher than limits for some of the other disposition pathways currently available. At this time, these scoping tests did not evaluate the partitioning of the radionuclides to the evaporator condensate, since ample data are available separately from other experience in the DOE complex. Results from the evaporation testing show that the neutral SBS simulant first forms turbidity at ~7.5X concentration, while the alkaline-adjusted simulant became turbid at ~3X concentration. The major solid in both cases was Kogarkoite, Na3FSO4. Sodium and lithium fluorides were also detected. Minimal solids were formed in the evaporator bottoms until a substantial fraction of liquid was removed, indicating that evaporation could minimize storage volume issues. Achievable concentration factors without significant insoluble solids were 17X at alkaline pH, and 23X at neutral pH. In both runs, significant ammonia carried over and was captured in the condenser with the water condensate. Results also indicate that with low insoluble solids formation in the initial testing at neutral pH, the use of Reverse Osmosis is a potential alternate method for concentrating the solution, although an evaluation is needed to identify equipment that can tolerate insoluble solids. Most of the ammonia remains in the evaporator bottoms during the neutral pH evaporation, but partitions to the condensate during alkaline evaporation. Disposition of both streams needs to consider the management of ammonia vapor and its release. Since this is an initial phase of testing, additional tasks related to evaporation methods are expected to be identified for development. These tasks likely include evaluation and testing of composition variability testing and evaluations, corrosion and erosion testing, slurry storage and immobilization investigations, and evaporator condensate disposition.« less
This report provides an evaluation of the potential applicability of Assembled Chemical Weapons Assessment (ACWA) technologies to RCRA waste streams and contaminated media found at RCRA and Superfund sites.
Pervaporation process and use in treating waste stream from glycol dehydrator
Kaschemekat, Jurgen; Baker, Richard W.
1994-01-01
Pervaporation processes and apparatus with few moving parts. Ideally, only one pump is used to provide essentially all of the motive power and driving force needed. The process is particularly useful for handling small streams with flow rates less than about 700 gpd. Specifically, the process can be used to treat waste streams from glycol dehydrator regeneration units.
Yao, Jun; Chen, Luxi; Zhu, Huayue; Shen, Dongsheng; Qiu, Zhanhong
2017-04-01
Simulated landfill was operated for 508 days to investigate the effect of municipal solid waste incinerator (MSWI) bottom ash layer on the migration of nitrate, nitrite, and ammonia when it was used as the intermediate layer in the landfill. The result suggested that the MSWI bottom ash layer could capture the nitrate, nitrite, and ammonia from the leachate. The adsorption of the nitrate, nitrite, and ammonia on the MSWI bottom ash layer was saturated at the days 396, 34, and 97, respectively. Afterwards, the nitrogen species were desorbed from the MSWI bottom ash layer. Finally, the adsorption and desorption could reach the equilibrium. The amounts of adsorbed nitrate and nitrite on the MSWI bottom ash layer were 1685.09 and 7.48 mg, respectively, and the amount of the adsorbed and transformed ammonia was 13,773.19 mg, which was much higher than the desorbed. The water leaching test and synthetic precipitation leaching procedure (SPLP) results showed that the leachable nitrate, nitrite, and ammonia in the MSWI bottom ash were greatly increased after the landfill operation, suggesting that the adsorbed nitrogen could be finally leached out. Besides, the results also showed that MSWI bottom ash layer could affect the release of nitrate and ammonia at the initial stage of the landfill. However, it had little effect on the release of nitrite.
Using Bacterial Growth on Insects to Assess Nutrient Impacts in Streams
A. Dennis Lemly
2000-01-01
A combination field and laboratory study was conducted to evaluate the ability of a recently developed bioindicator to detect detrimental nutrient conditions in streams. The method utilizes bacterial growth on aquatic insects to determine nutrient impacts. Field investigations indicated that elevated concentrations of nitrate and phosphate were associated with growth...
Laura T. Johnson; Jennifer L. Tank; Robert O. Hall; Patrick J. Mullholland; Stephen K. Hamilton; H. Maurice Valett; Jackson R. Webster; Melody J. Bernot; William H. McDowell; Bruce J. Peterson; Suzanne M. Thomas
2013-01-01
Most nitrogen (N) assimilation in lake and marine ecosystems is often subsequently released via autochthonous dissolved organic nitrogen (DON) production, but autochthonous DON production has yet to be quantified in flowing waters. We measured in-stream DON production following 24 h 15N-nitrate (NO3-...
Determining the role of hydrologic variability on DIN export from the Catskill Mountains
The Catskill region of New York State receives some of the highest rates of atmospheric nitrogen deposition in the northeastern US (approximately 6.2 kg ha-1 yr-1), and headwater streams have elevated nitrate concentrations (mean of stream surveys = 0.27 – 0.35 mg N l-1). Althou...
Clearcutting affects stream chemistry in the White Mountains of New Hampshire
C. Wayne Martin; Robert S. Pierce; Gene E. Likens; F. Herbert Bormann; F. Herbert Bormann
1986-01-01
Commercial clearcutting of northern hardwood forests changed the chemistry of the streams that drained from them. By the second year after cutting, specific conductance doubled, nitrate increased tenfold, calcium tripled, and sodium, magnesium, and potassium doubled. Chloride and ammonium did not change; sulfate decreased. Concentrations of most ions returned to...
Endogenous and exogenous control of ecosystem function: N cycling in headwater streams.
Valett, H M; Thomas, S A; Mulholland, P J; Webster, J R; Dahm, C N; Fellows, C S; Crenshaw, C L; Peterson, C G
2008-12-01
Allochthonous inputs act as resource subsidies to many ecosystems, where they exert strong influences on metabolism and material cycling. At the same time, metabolic theory proposes endogenous thermal control independent of resource supply. To address the relative importance of exogenous and endogenous influences, we quantified spatial and temporal variation in ecosystem metabolism and nitrogen (N) uptake using seasonal releases of 15N as nitrate in six streams differing in riparian-stream interaction and metabolic character. Nitrate removal was quantified using a nutrient spiraling approach based on measurements of downstream decline in 15N flux. Respiration (R) and gross primary production (GPP) were measured with whole-stream diel oxygen budgets. Uptake and metabolism metrics were addressed as z scores relative to site means to assess temporal variation. In open-canopied streams, areal uptake (U; microg N x m(-2) x s(-1)) was closely related to GPP, metabolic rates increased with temperature, and R was accurately predicted by metabolic scaling relationships. In forested streams, N spiraling was not related to GPP; instead, uptake velocity (v(f); mm/s) was closely related to R. In contrast to open-canopied streams, N uptake and metabolic activity were negatively correlated to temperature and poorly described by scaling laws. We contend that streams differ along a gradient of exogenous and endogenous control that relates to the relative influences of resource subsidies and in-stream energetics as determinants of seasonal patterns of metabolism and N cycling. Our research suggests that temporal variation in the propagation of ecological influence between adjacent systems generates phases when ecosystems are alternatively characterized as endogenously and exogenously controlled.
Predicting redox conditions in groundwater at a regional scale
Tesoriero, Anthony J.; Terziotti, Silvia; Abrams, Daniel B.
2015-01-01
Defining the oxic-suboxic interface is often critical for determining pathways for nitrate transport in groundwater and to streams at the local scale. Defining this interface on a regional scale is complicated by the spatial variability of reaction rates. The probability of oxic groundwater in the Chesapeake Bay watershed was predicted by relating dissolved O2 concentrations in groundwater samples to indicators of residence time and/or electron donor availability using logistic regression. Variables that describe surficial geology, position in the flow system, and soil drainage were important predictors of oxic water. The probability of encountering oxic groundwater at a 30 m depth and the depth to the bottom of the oxic layer were predicted for the Chesapeake Bay watershed. The influence of depth to the bottom of the oxic layer on stream nitrate concentrations and time lags (i.e., time period between land application of nitrogen and its effect on streams) are illustrated using model simulations for hypothetical basins. Regional maps of the probability of oxic groundwater should prove useful as indicators of groundwater susceptibility and stream susceptibility to contaminant sources derived from groundwater.
TREATMENT OF AMMONIUM NITRATE SOLUTIONS
Boyer, T.W.; MacHutchin, J.G.; Yaffe, L.
1958-06-10
The treatment of waste solutions obtained in the processing of neutron- irradiated uranium containing fission products and ammonium nitrate is described. The object of this process is to provide a method whereby the ammonium nitrate is destroyed and removed from the solution so as to permit subsequent concentration of the solution.. In accordance with the process the residual nitrate solutions are treated with an excess of alkyl acid anhydride, such as acetic anhydride. Preferably, the residual nitrate solution is added to an excess of the acetic anhydride at such a rate that external heat is not required. The result of this operation is that the ammonium nitrate and acetic anhydride react to form N/sub 2/ O and acetic acid.
Jill Crossman; M. Catherine Eimers; Nora J. Casson; Douglas A. Burns; John L. Campbell; Gene E. Likens; Myron J. Mitchell; Sarah J. Nelson; James B. Shanley; Shaun A. Watmough; Kara L. Webster
2016-01-01
This study evaluated the contribution of winter rain-on-snow (ROS) events to annual and seasonal nitrate (N-NO3) export and identified the regional meteorological drivers of inter-annual variability in ROS N-NO3 export (ROS-N) at 9 headwater streams located across Ontario, Canada and the northeastern United States. Although...
Are nitrate exports in stream water linked to nitrogen fluxes in decomposing foliar litter?
Kathryn B. Piatek; Mary Beth Adams
2011-01-01
The central hardwood forest receives some of the highest rates of atmospheric nitrogen (N) deposition, which results in nitrate leaching to surface waters. Immobilization of N in foliar litter during litter decomposition represents a potential mechanism for temporal retention of atmospherically deposited N in forest ecosystems. When litter N dynamics switch to the N-...
This study investigated the extent to which nitrate was removed from and/or stored in a small wetland depression downgradient of a 10-ha cattle rotational grazing pasture and a 2.5-ha cropped catchment at the USDA-ARS J. Phil Campbell Sr. Natural Resource Conservation Center in W...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carroad, P.A.; Wilke, C.R.
1976-12-01
Bioconversion of food processing wastes is receiving increased attention with the realization that waste components represent an available and utilizable resource for conversion to useful products. Liquid wastes are characterized as dilute streams containing sugars, starches, proteins, and fats. Solid wastes are generally cellulosic, but may contain other biopolymers. The greatest potential for economic bioconversion is represented by processes to convert cellulose to glucose, glucose to alcohol and protein, starch to invert sugar, and dilute waste streams to methane by anaerobic digestion. Microbial or enzymatic processes to accomplish these conversions are described.
Quality control in the recycling stream of PVC from window frames by hyperspectral imaging
NASA Astrophysics Data System (ADS)
Luciani, Valentina; Serranti, Silvia; Bonifazi, Giuseppe; Di Maio, Francesco; Rem, Peter
2013-05-01
Polyvinyl chloride (PVC) is one of the most commonly used thermoplastic materials in respect to the worldwide polymer consumption. PVC is mainly used in the building and construction sector, products such as pipes, window frames, cable insulation, floors, coverings, roofing sheets, etc. are realised utilising this material. In recent years, the problem of PVC waste disposal gained increasing importance in the public discussion. The quantity of used PVC items entering the waste stream is gradually increased as progressively greater numbers of PVC products approach to the end of their useful economic lives. The quality of the recycled PVC depends on the characteristics of the recycling process and the quality of the input waste. Not all PVC-containing waste streams have the same economic value. A transparent relation between value and composition is required to decide if the recycling process is cost effective for a particular waste stream. An objective and reliable quality control technique is needed in the recycling industry for the monitoring of both recycled flow streams and final products in the plant. In this work hyperspectral imaging technique in the near infrared (NIR) range (1000-1700 nm) was applied to identify unwanted plastic contaminants and rubber present in PVC coming from windows frame waste in order to assess a quality control procedure during its recycling process. Results showed as PVC, PE and rubber can be identified adopting the NIR-HSI approach.
NASA Astrophysics Data System (ADS)
Burt, T.; Worrall, F.
2008-12-01
A 35-year record of nitrate concentration for the Slapton Wood stream, a small agricultural catchment in south west England, is presented. The study reconsiders earlier work in order to assess whether upward trends have been maintained and how controls on catchment nitrate processes have altered. The study has shown that: (i) the catchment has reached a new position of equilibrium and increases in nitrate concentration have levelled off; (ii) the occurrence of severe droughts means that records of less than a decade are misleading and only longer records can illustrate changes of system state; (iii) the change of state observed in the catchment is illustrated in the switching of long-term memory effects from a negative to a positive annual memory; (iv) a significant long-term impulsivity relationship with rainfall becomes insignificant over the course of the study period. The study shows the importance of long records in exposing changes in state in catchment systems and understanding the time constants of a range of driving processes. The study by its very nature also demonstrates the importance of maintaining long-term monitoring programmes.
Wang, Peng; Liu, Junzheng; Qi, Shuhua; Wang, Shiqin; Chen, Xiaoling
2017-10-01
In this work, we traced sources of nitrate in the Ganjiang River, a major tributary of Yangtze River, China, by analysing the water chemistry, nitrogen isotopes and land use. Water samples from 20 sites in the main stream and tributaries were collected in the dry and wet seasons. The [Formula: see text] ranged from 0.97 to 8.60 ‰, and was significantly higher in the wet season than in the dry season, and significantly higher in tributaries than in the main stream. In the dry season, [Formula: see text] concentrations and [Formula: see text] were significantly negatively correlated with forest and grassland areas, and positively correlated with paddy field and residential area. However, most of the correlations were not significant in the wet season. The results showed that fertilizer was the main source of nitrate in the Ganjiang River, and domestic sewage was important in the dry season, but its contribution was lower than that in other rivers in the Yangtze Basin. In the wet season, the intensified nitrogen cycle caused by high temperature and the mixing effect caused by rainfall made it difficult to trace nitrate sources using [Formula: see text] and land use.
Triska, F.J.; Duff, J.H.; Sheibley, R.W.; Jackman, A.P.; Avanzino, R.J.
2007-01-01
Dissolved inorganic nitrogen (DIN) retention-transport through a headwater catchment was synthesized from studies encompassing four distinct hydrologic zones of the Shingobee River Headwaters near the origin of the Mississippi River. The hydrologic zones included: (1) hillslope ground water (ridge to bankside riparian); (2) alluvial riparian ground water; (3) ground water discharged through subchannel sediments (hyporheic zone); and (4) channel surface water. During subsurface hillslope transport through Zone 1, DIN, primarily nitrate, decreased from ???3 mg-N/l to <0.1 mg-N/l. Ambient seasonal nitrate:chloride ratios in hillslope flow paths indicated both dilution and biotic processing caused nitrate loss. Biologically available organic carbon controlled biotic nitrate retention during hillslope transport. In the alluvial riparian zone (Zone 2) biologically available organic carbon controlled nitrate depletion although processing of both ambient and amended nitrate was faster during the summer than winter. In the hyporheic zone (Zone 3) and stream surface water (Zone 4) DIN retention was primarily controlled by temperature. Perfusion core studies using hyporheic sediment indicated sufficient organic carbon in bed sediments to retain ground water DIN via coupled nitrification-denitrification. Numerical simulations of seasonal hyporheic sediment nitrification-denitrification rates from perfusion cores adequately predicted surface water ammonium but not nitrate when compared to 5 years of monthly field data (1989-93). Mass balance studies in stream surface water indicated proportionally higher summer than winter N retention. Watershed DIN retention was effective during summer under the current land use of intermittently grazed pasture. However, more intensive land use such as row crop agriculture would decrease nitrate retention efficiency and increase loads to surface water. Understanding DIN retention capacity throughout the system, including special channel features such as sloughs, wetlands and floodplains that provide surface water-ground water connectivity, will be required to develop effective nitrate management strategies. ?? 2007 American Water Resources Association.
Monitoring Nitrate, Chlorophyll, and CDOM Cycling in a Reservoir using In Situ Mapping Techniques
NASA Astrophysics Data System (ADS)
OConnor, J.; Showers, W. J.; Osburn, C. L.; DeMaster, D. J.
2013-12-01
Degradation of surface waters due to increased nutrient loading and subsequent eutrophication is a persistent problem on a global scale. Expanding human populations and their associated development create increased pressure on local watersheds in terms of both point and non-point source pollution. In this study a suite of in situ sensors measuring nitrate concentration, chlorophyll a concentration (Chl a), and chromophoric dissolved organic material (CDOM) fluorescence were deployed from a rapidly moving boat (~32 km/h) in order to identify sources of nutrients and CDOM, and to determine their relationship to eutrophication symptoms in Falls Lake, North Carolina. In addition, water samples were collected throughout the lake and from tributaries of interest for laboratory analysis. Results indicated the three main tributaries at the north end of the lake were the important contributors of both nitrate and CDOM. While two of the three were degraded due to significant effluent discharge from Waste Water Treatment Plants, the third appeared to be impacted by diffuse nutrient sources. However, atmospheric deposition of nitrate and ammonium exceeded tributary input, and the net nutrient loading to the lake was dominated by sediment release of both ammonium and phosphate. No direct relationship between nitrate and Chl a concentrations was observed, but bays that sewage impacted rivers emptied into displayed elevated Chl a values. Water samples from both the lake and streams were analyzed for stable isotopic analysis of δ15N and δ18O composition and were consistent with waste as the primary source of nitrate. Samples were also analyzed for CDOM absorbance and fluorescence through the creation of Excitation and Emission Matrices (EEMs) and the development of a nine component PARAFAC model. Fluorescence values consistently declined from the north end of the lake to the southern end at the dam and water treatment plant intake. Absorbance values at 254 nm (a254) also showed a decreasing trend from north to south, while SR increased. The loss of absorption could have been caused by photobleaching, however, a hydrologic modeling experiment demonstrated that this change in optical character was actually due to mixing of un-polluted tributary and rain water with water from the main tributaries at the north end. At the southern end of the lake, adjacent to the water treatment plant intake, a series of depth profiles were made that revealed a stratified water column during summer months. There was evidence of production of CDOM in the anoxic hypolimnion that appeared to be linked to an increase in Chl a concentration. There was also a significant increase in a254 and a decrease in SR that suggested CDOM was released from the sediments in the hypolimnion. This study showed that the north end of the lake suffered from persistent eutrophication symptoms. However, as the water traveled south to the two exit points at the dam and the water treatment plant, water quality improved.
Glass Ceramic Waste Forms for Combined CS+LN+TM Fission Products Waste Streams
DOE Office of Scientific and Technical Information (OSTI.GOV)
Crum, Jarrod V.; Turo, Laura A.; Riley, Brian J.
2010-09-23
In this study, glass ceramics were explored as an alternative waste form for glass, the current baseline, to be used for immobilizing alkaline/alkaline earth + lanthanide (CS+LN) or CS+LN+transition metal (TM) fission-product waste streams generated by a uranium extraction (UREX+) aqueous separations type process. Results from past work on a glass waste form for the combined CS+LN waste streams showed that as waste loading increased, large fractions of crystalline phases precipitated upon slow cooling.[1] The crystalline phases had no noticeable impact on the waste form performance by the 7-day product consistency test (PCT). These results point towards the development ofmore » a glass ceramic waste form for treating CS+LN or CS+LN+TM combined waste streams. Three main benefits for exploring glass ceramics are: (1) Glass ceramics offer increased solubility of troublesome components in crystalline phases as compared to glass, leading to increased waste loading; (2) The crystalline network formed in the glass ceramic results in higher heat tolerance than glass; and (3) These glass ceramics are designed to be processed by the same melter technology as the current baseline glass waste form. It will only require adding controlled canister cooling for crystallization into a glass ceramic waste form. Highly annealed waste form (essentially crack free) with up to 50X lower surface area than a typical High-Level Waste (HLW) glass canister. Lower surface area translates directly into increased durability. This was the first full year of exploring glass ceramics for the Option 1 and 2 combined waste stream options. This work has shown that dramatic increases in waste loading are achievable by designing a glass ceramic waste form as an alternative to glass. Table S1 shows the upper limits for heat, waste loading (based on solubility), and the decay time needed before treatment can occur for glass and glass ceramic waste forms. The improvements are significant for both combined waste stream options in terms of waste loading and/or decay time required before treatment. For Option 1, glass ceramics show an increase in waste loading of 15 mass % and reduction in decay time of 24 years. Decay times of {approx}50 years or longer are close to the expected age of the fuel that will be reprocessed when the modified open or closed fuel cycle is expected to be put into action. Option 2 shows a 2x to 2.5x increase in waste loading with decay times of only 45 years. Note that for Option 2 glass, the required decay time before treatment is only 35 years because of the waste loading limits related to the solubility of MoO{sub 3} in glass. If glass was evaluated for similar waste loadings as those achieved in Option 2 glass ceramics, the decay time would be significantly longer than 45 years. These glass ceramics are not optimized, but already they show the potential to dramatically reduce the amount of waste generated while still utilizing the proven processing technology used for glass production.« less
Koutinas, Apostolis A; Vlysidis, Anestis; Pleissner, Daniel; Kopsahelis, Nikolaos; Lopez Garcia, Isabel; Kookos, Ioannis K; Papanikolaou, Seraphim; Kwan, Tsz Him; Lin, Carol Sze Ki
2014-04-21
The transition from a fossil fuel-based economy to a bio-based economy necessitates the exploitation of synergies, scientific innovations and breakthroughs, and step changes in the infrastructure of chemical industry. Sustainable production of chemicals and biopolymers should be dependent entirely on renewable carbon. White biotechnology could provide the necessary tools for the evolution of microbial bioconversion into a key unit operation in future biorefineries. Waste and by-product streams from existing industrial sectors (e.g., food industry, pulp and paper industry, biodiesel and bioethanol production) could be used as renewable resources for both biorefinery development and production of nutrient-complete fermentation feedstocks. This review focuses on the potential of utilizing waste and by-product streams from current industrial activities for the production of chemicals and biopolymers via microbial bioconversion. The first part of this review presents the current status and prospects on fermentative production of important platform chemicals (i.e., selected C2-C6 metabolic products and single cell oil) and biopolymers (i.e., polyhydroxyalkanoates and bacterial cellulose). In the second part, the qualitative and quantitative characteristics of waste and by-product streams from existing industrial sectors are presented. In the third part, the techno-economic aspects of bioconversion processes are critically reviewed. Four case studies showing the potential of case-specific waste and by-product streams for the production of succinic acid and polyhydroxyalkanoates are presented. It is evident that fermentative production of chemicals and biopolymers via refining of waste and by-product streams is a highly important research area with significant prospects for industrial applications.
Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Kärki, Janne
2014-08-01
This paper presents the mass, energy and material balances of a solid recovered fuel (SRF) production process. The SRF is produced from commercial and industrial waste (C&IW) through mechanical treatment (MT). In this work various streams of material produced in SRF production process are analyzed for their proximate and ultimate analysis. Based on this analysis and composition of process streams their mass, energy and material balances are established for SRF production process. Here mass balance describes the overall mass flow of input waste material in the various output streams, whereas material balance describes the mass flow of components of input waste stream (such as paper and cardboard, wood, plastic (soft), plastic (hard), textile and rubber) in the various output streams of SRF production process. A commercial scale experimental campaign was conducted on an MT waste sorting plant to produce SRF from C&IW. All the process streams (input and output) produced in this MT plant were sampled and treated according to the CEN standard methods for SRF: EN 15442 and EN 15443. The results from the mass balance of SRF production process showed that of the total input C&IW material to MT waste sorting plant, 62% was recovered in the form of SRF, 4% as ferrous metal, 1% as non-ferrous metal and 21% was sorted out as reject material, 11.6% as fine fraction, and 0.4% as heavy fraction. The energy flow balance in various process streams of this SRF production process showed that of the total input energy content of C&IW to MT plant, 75% energy was recovered in the form of SRF, 20% belonged to the reject material stream and rest 5% belonged with the streams of fine fraction and heavy fraction. In the material balances, mass fractions of plastic (soft), plastic (hard), paper and cardboard and wood recovered in the SRF stream were 88%, 70%, 72% and 60% respectively of their input masses to MT plant. A high mass fraction of plastic (PVC), rubber material and non-combustibles (such as stone/rock and glass particles), was found in the reject material stream. Copyright © 2014 Elsevier Ltd. All rights reserved.
PERFORMANCE EVALUATION OF A CARBON-BASED REACTIVE BARRIER FOR NITRATE REMEDIATION
Nitrate (NO3-) is a common ground water contaminant related to agricultural activity, waste water disposal, leachate from landfills, septic systems, and industrial processes. This study reports on the performance of a carbon-based permeable reactive barrier (PRB) that was constr...
CARBON-BASED REACTIVE BARRIER FOR NITRATE REMEDIATION AT A FORMER SWINE CAFO
Nitrate (NO3-) is a common ground water contaminant related to agricultural activity, waste water disposal, leachate from landfills, septic systems, and industrial processes. This study reports on the performance of a carbon-based permeable reactive barrier (PRB) that was constr...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hu Lin Li; Robertson, D.H.; Chambers, J.Q.
1996-10-01
This work describes the electrochemical reduction of nitrate in alkaline solutions. Conditions which maximize the current efficiency for the production of dinitrogen and/or ammonia gases could be very important for the treatment of radioactive waste solutions.
Promoting nitrate removal in rain gardens | Science Inventory ...
Rain gardens are vegetated surface depressions, often located at low points in landscapes, designed to receive stormwater runoff from roads, roofs, and parking lots. The gardens’ sandy soils allow stormwater to drain quickly to the native soils below and eventually to groundwater. The rain garden vegetation and soils remove pollutants and nutrients from stormwater runoff through biological and physical processes such as plant uptake and sorption to soil particles. In comparison with stormwater release to receiving waters through conventional storm drain systems, infiltrating stormwater through rain gardens reduces peak flows and loadings of both pollutants and nutrients. This reduction improves the physical and biological integrity of receiving streams by reducing stream bank erosion and negative effects on stream communities. While local governments and individual homeowners are building these systems, relatively few scientific studies have documented the ability of rain gardens to remove pollutants and nutrients. This U.S. EPA long-term research project investigates: 1) the performance of rain gardens in removing pollutants, and 2) whether currently-accepted design standards can be adjusted to improve nitrate removal capabilities. Typical rain garden designs provide large removals of pollutants of concern, including heavy metals, phosphorus, total nitrogen, and ammonium. The gardens have been less successful in removing nitrate, an importan
Carbon and nitrogen stoichiometry across stream ecosystems
NASA Astrophysics Data System (ADS)
Wymore, A.; Kaushal, S.; McDowell, W. H.; Kortelainen, P.; Bernhardt, E. S.; Johnes, P.; Dodds, W. K.; Johnson, S.; Brookshire, J.; Spencer, R.; Rodriguez-Cardona, B.; Helton, A. M.; Barnes, R.; Argerich, A.; Haq, S.; Sullivan, P. L.; López-Lloreda, C.; Coble, A. A.; Daley, M.
2017-12-01
Anthropogenic activities are altering carbon and nitrogen concentrations in surface waters globally. The stoichiometry of carbon and nitrogen regulates important watershed biogeochemical cycles; however, controls on carbon and nitrogen ratios in aquatic environments are poorly understood. Here we use a multi-biome and global dataset (tropics to Arctic) of stream water chemistry to assess relationships between dissolved organic carbon (DOC) and nitrate, ammonium and dissolved organic nitrogen (DON), providing a new conceptual framework to consider interactions between DOC and the multiple forms of dissolved nitrogen. We found that across streams the total dissolved nitrogen (TDN) pool is comprised of very little ammonium and as DOC concentrations increase the TDN pool shifts from nitrate to DON dominated. This suggests that in high DOC systems, DON serves as the primary source of nitrogen. At the global scale, DOC and DON are positively correlated (r2 = 0.67) and the average C: N ratio of dissolved organic matter (molar ratio of DOC: DON) across our data set is approximately 31. At the biome and smaller regional scale the relationship between DOC and DON is highly variable (r2 = 0.07 - 0.56) with the strongest relationships found in streams draining the mixed temperate forests of the northeastern United States. DOC: DON relationships also display spatial and temporal variability including latitudinal and seasonal trends, and interactions with land-use. DOC: DON ratios correlated positively with gradients of energy versus nutrient limitation pointing to the ecological role (energy source versus nutrient source) that DON plays with stream ecosystems. Contrary to previous findings we found consistently weak relationships between DON and nitrate which may reflect DON's duality as an energy or nutrient source. Collectively these analyses demonstrate how gradients of DOC drive compositional changes in the TDN pool and reveal a high degree of variability in the C: N ratio (3-100) of stream water dissolved organic matter.
Generating revenue from X-ray waste.
Hundal, Simon
2013-09-01
According to Betts Envirometal, experts in precious metal recovery from waste streams, and a provider of 'total waste management' solutions, 'disposing of hospital wastes isn't usually a glamorous subject, unless, of course, you know how to make money from it'. As general manager, Simon Hundal, explains, the company is seeking to 'revolutionise' how the NHS treats certain waste streams, and, in doing so, to encourage NHS Trust directors and governance managers to check their compliance with patient data retention guidelines as far as medical X-ray film, in particular, is concerned.
DOE Office of Scientific and Technical Information (OSTI.GOV)
R.H. Little, P.R. Maul, J.S.S. Penfoldag
2003-02-27
This paper describes and presents the findings from two studies undertaken for the European Commission to assess the long-term impact upon the environment and human health of non-radioactive contaminants found in various low level radioactive waste streams. The initial study investigated the application of safety assessment approaches developed for radioactive contaminants to the assessment of nonradioactive contaminants in low level radioactive waste. It demonstrated how disposal limits could be derived for a range of non-radioactive contaminants and generic disposal facilities. The follow-up study used the same approach but undertook more detailed, disposal system specific calculations, assessing the impacts of bothmore » the non-radioactive and radioactive contaminants. The calculations undertaken indicated that it is prudent to consider non-radioactive, as well as radioactive contaminants, when assessing the impacts of low level radioactive waste disposal. For some waste streams with relatively low concentrations of radionuclides, the potential post-closure disposal impacts from non-radioactive contaminants can be comparable with the potential radiological impacts. For such waste streams there is therefore an added incentive to explore options for recycling the materials involved wherever possible.« less
Electrochemical/Pyrometallurgical Waste Stream Processing and Waste Form Fabrication
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steven Frank; Hwan Seo Park; Yung Zun Cho
This report summarizes treatment and waste form options being evaluated for waste streams resulting from the electrochemical/pyrometallurgical (pyro ) processing of used oxide nuclear fuel. The technologies that are described are South Korean (Republic of Korea – ROK) and United States of America (US) ‘centric’ in the approach to treating pyroprocessing wastes and are based on the decade long collaborations between US and ROK researchers. Some of the general and advanced technologies described in this report will be demonstrated during the Integrated Recycle Test (IRT) to be conducted as a part of the Joint Fuel Cycle Study (JFCS) collaboration betweenmore » US Department of Energy (DOE) and ROK national laboratories. The JFCS means to specifically address and evaluated the technological, economic, and safe guard issues associated with the treatment of used nuclear fuel by pyroprocessing. The IRT will involve the processing of commercial, used oxide fuel to recover uranium and transuranics. The recovered transuranics will then be fabricated into metallic fuel and irradiated to transmutate, or burn the transuranic elements to shorter lived radionuclides. In addition, the various process streams will be evaluated and tested for fission product removal, electrolytic salt recycle, minimization of actinide loss to waste streams and waste form fabrication and characterization. This report specifically addresses the production and testing of those waste forms to demonstrate their compatibility with treatment options and suitability for disposal.« less
'Low-acid' sulfide oxidation using nitrate-enriched groundwater
NASA Astrophysics Data System (ADS)
Donn, Michael; Boxall, Naomi; Reid, Nathan; Meakin, Rebecca; Gray, David; Kaksonen, Anna; Robson, Thomas; Shiers, Denis
2016-04-01
Acid drainage (AMD/ARD) is undoubtedly one of the largest environmental, legislative and economic challenges facing the mining industry. In Australia alone, at least 60m is spent on AMD related issues annually, and the global cost is estimated to be in the order of tens of billions US. Furthermore, the challenge of safely and economically storing or treating sulfidic wastes will likely intensify because of the trend towards larger mines that process increasingly higher volumes of lower grade ores and the associated sulfidic wastes and lower profit margins. While the challenge of managing potentially acid forming (PAF) wastes will likely intensify, the industrial approaches to preventing acid production or ameliorating the effects has stagnated for decades. Conventionally, PAF waste is segregated and encapsulated in non-PAF tips to limit access to atmospheric oxygen. Two key limitations of the 'cap and cover' approach are: 1) the hazard (PAF) is not actually removed; only the pollutant linkage is severed; and, 2) these engineered structures are susceptible to physical failure in short-to-medium term, potentially re-establishing that pollutant linkage. In an effort to address these concerns, CSIRO is investigating a passive, 'low-acid' oxidation mechanism for sulfide treatment, which can potentially produce one quarter as much acidity compared with pyrite oxidation under atmospheric oxygen. This 'low-acid' mechanism relies on nitrate, rather than oxygen, as the primary electron accepter and the activity of specifically cultured chemolithoautotrophic bacteria and archaea communities. This research was prompted by the observation that, in deeply weathered terrains of Australia, shallow (oxic to sub-oxic) groundwater contacting weathering sulfides are commonly inconsistent with the geochemical conditions produced by ARD. One key characteristic of these aquifers is the natural abundance of nitrate on a regional scale, which becomes depleted around the sulfide bodies, and where pH remains neutral. The "low-acid" oxidation of sulfides with nitrate as an electron acceptor has been demonstrated at the laboratory scale. In 90-day microcosm respirometry experiments, we exposed a mixture of pulverized quartz and pyrite -rich ore to natural, high-nitrate groundwater and inoculated the microcosms with a culture of aerobic and anaerobic nitrate-dependent iron and sulfur-oxidising microorganisms, which were enriched from ore, groundwater and activated waste water. Incubations were performed under both oxic and anoxic conditions, in addition to abiotic controls. Initial results show that oxidation of the sulfides under nitrate-rich and microbially enhanced conditions does produce less acid than the same material under oxic conditions, and to some degree can match the models as long as oxygen ingress can be controlled. These results are the focus of further research into how this process can be enhanced and whether it can be applied in the field. Nitrate-driven oxidation of sulfides could potentially be used as a new approach to reduce acid generation and leaching of contaminants from waste dumps, in a passive or actively managed process designed to deplete and/or ameliorate (i.e. through surface passivation) the mineralogical hazard. Developing our understanding of biological aspects of these processes may also allow testing of longer-term "bio-caps" for various tailings and dump materials.
Bathymetric mapping, sediment quality, and water quality of Lake Delhi, Iowa, 2001-02
Schnoebelen, Douglas J.; McVay, Jason C.; Barnes, Kimberlee K.; Becher, Kent D.
2003-01-01
Water-quality sampling results indicate areas affected by elevated nutrient and bacteria concentrations in the lake and tributary streams. The tributary streams had the highest median nitrate concentrations (12.1 milligrams per liter) when compared to median nitrate concentrations in the lake (8.7 milligrams per liter) or the Maquoketa River (10.5 milligrams per liter). The maximum nitrate concentrations detected for Maquoketa River, lake, and tributary sites were 13.5, 13.5, and 18.6 milligrams per liter, respectively. Nitrate concentrations in the late summer decreased from 2 Bathymetric Mapping, Sediment Quality, and Water Quality of Lake Delhi, Iowa, 2001–02 the upstream (7.8 milligrams per liter) to the downstream (5.0 milligrams per liter) one-third of Lake Delhi and most likely were the result of uptake of nitrate by algae and aquatic biota in the lake. Median concentrations of total coliform and E. coli bacteria for the lake sites were 450 and 17 colonies per 100 milliliters of sample, respectively. The U.S. Environmental Protection Agency criteria for full body contact (swimming or bathing) are 200 colonies per 100 milliliters for fecal bacteria and 126 colonies per 100 milliliters for E. coli bacteria. The highest bacteria concentrations in the lake occurred after a rain and were 25,000 colonies per 100 milliliters total coliform and 1,900 colonies per 100 milliliters E. coli.
NASA Astrophysics Data System (ADS)
Trauth, Nico; Schmidt, Christian; Fleckenstein, Jan H.
2015-04-01
Groundwater-surface water exchange is an important process that can facilitate the degradation of critical substances like nitrogen-species and contaminants, supporting a healthy status of the aquatic ecosystem. In our study, we simulate water exchange, solute transport and reactions within a natural in-stream gravel bar using a coupled surface and subsurface numerical model. Stream water flow is simulated by computational fluid dynamics software that provides hydraulic head distributions at the streambed, which are used as an upper boundary condition for a groundwater model. In the groundwater model water exchange, solute transport, aerobic respiration and denitrification in the subsurface are simulated. Ambient groundwater flow is introduced by lateral upstream and downstream hydraulic head boundaries that generate neutral, losing or gaining stream conditions. Stream water transports dissolved oxygen, organic carbon (as the dominant electron donor) and nitrate into the subsurface, whereas an additional nitrate source exists in the ambient groundwater. Scenarios of stream flow events varying in duration and stream stage are simulated and compared with steady state scenarios with respect to water fluxes, residence times and the solute turn-over rates. Results show, that water exchange and solute turn-over rates highly depend on the interplay between event characteristics and ambient groundwater levels. For scenarios, where the stream flow event shifts the hydraulic system to a net-neutral hydraulic gradient between the average stream stage and the ambient groundwater level (minimal exchange between ground- and surface water), solute consumption is higher, compared to the steady losing or gaining case. In contrast, events that induce strong losing conditions lead to a lower potential of solute consumption.
Electrolytic Removal of Nitrate From CELSS Crop Residues
NASA Technical Reports Server (NTRS)
Colon, Guillermo; Sager, John
1996-01-01
The controlled ecological life support system (CELSS) resource recovery system is a waste processing system using aerobic and anaerobic bioreactors to recover plant nutrients and secondary foods from inedible biomass. Crop residues contain significant amounts of nitrate which presents two problems: (1) both CELSS biomass production and resource recovery consume large quantities of nitric acid, (2) nitrate causes a variety of problems in both aerobic and anaerobic bioreactors. A technique was proposed to remove the nitrate from potato inedible biomass leachate and to satisfy the nitric acid demand using a four compartment electrolytic cell.
Crain, Angela S.
2006-01-01
Nutrients, primarily nitrogen and phosphorus compounds, naturally occur but also are applied to land in the form of commercial fertilizers and livestock waste to enhance plant growth. Concentrations, estimated loads and yields, and sources of nitrite plus nitrate, total phosphorus, and orthophosphate were evaluated in streams of the Little River Basin to assist the Commonwealth of Kentucky in developing 'total maximum daily loads' (TMDLs) for streams in the basin. The Little River Basin encompasses about 600 square miles in Christian and Trigg Counties, and a portion of Caldwell County in western Kentucky. Water samples were collected in streams in the Little River Basin during 2003-04 as part of a study conducted in cooperation with the Kentucky Department of Agriculture. A total of 92 water samples were collected at four fixed-network sites from March through November 2003 and from February through November 2004. An additional 20 samples were collected at five synoptic-network sites during the same period. Median concentrations of nitrogen, phosphorus, and suspended sediment varied spatially and seasonally. Concentrations of nitrogen were higher in the spring (March-May) after fertilizer application and runoff. The highest concentration of nitrite plus nitrate-5.7 milligrams per liter (mg/L)-was detected at the South Fork Little River site. The Sinking Fork near Cadiz site had the highest median concentration of nitrite plus nitrate (4.6 mg/L). The North Fork Little River site and the Little River near Cadiz site had higher concentrations of orthophosphate in the fall and lower concentrations in the spring. Concentrations of orthophosphate remained high during the summer (June-August) at the North Fork Little River site possibly because of the contribution of wastewater effluent to streamflow. Fifty-eight percent of the concentrations of total phosphorus at the nine sites exceeded the U.S. Environmental Protection Agency recommended maximum concentration limit of 0.1 mg/L. Concentrations of suspended sediment were highest in the spring during runoff and lowest in the fall. The highest concentration of suspended sediment (1,020 mg/L) was observed at the Sinking Fork near Cadiz site. The median concentration of suspended sediment for all sites sampled was 12 mg/L. A nonparameteric statistical test (Wilcoxson rank-sum) showed that the median concentrations of suspended sediment were not different among any of the fixed-network sites. The Little River near Cadiz site contributed larger estimated mean annual loads of nitrite plus nitrate (2,500,000 pounds per year (lb/yr)) and total phosphorus (160,000 lb/yr) than the other three fixed-network sites. Of the two main upstream tributaries from the Little River near Cadiz site, the North Fork Little River was the greatest contributor of total phosphorus to the study area with an estimated mean annual load of 107,000 lb/yr or about 64 percent of the total estimated mean annual load at the Little River near Cadiz site. The other main upstream tributary, South Fork Little River, had an estimated mean annual load of total phosphorus that was about 20 percent of the mean annual load at the Little River near Cadiz site. Estimated loads of suspended sediment were largest at the Little River near Cadiz site, where the estimated mean annual load for 2003-04 was about 84,000,000 lb/yr. The North Fork Little River contributed an estimated 36 percent of the mean annual load of suspended sediment at the Little River near Cadiz site, while the South Fork Little River contributed an estimated 18 percent of the mean annual load at the Little River near Cadiz site. The North Fork Little River site had the largest estimated mean annual yield of total phosphorus (1,600 pounds per year per square mile (lb/yr/mi2)) and orthophosphate (1,100 lb/yr/mi2). A principal source of phosphorus for the North Fork Little River is discharge from wastewater-treatment facilities. The largest estimated mean annual yield of nitrite plus nitrate was observed at the South Fork Little River site. The North Fork Little River site had the largest estimated mean annual yield of suspended sediment (450,000 lb/yr/mi2). Inputs of nitrogen and phosphorus to streams from point and nonpoint sources were estimated for the Little River Basin. Commercial fertilizer and livestock-waste applications on row crops are a principal source of nutrients for most of the Little River Basin. Sources of nutrients in the urban areas of the basin mainly are from effluent discharge from wastewater-treatment facilities and fertilizer applications to lawns and golf courses.
Sabo, Robert D.; Scanga, Sara E.; Lawrence, Gregory B.; Nelson, David M.; Eshleman, Keith N.; Zabala, Gabriel A.; Alinea, Alexandria A.; Schirmer, Charles D.
2016-01-01
Recent reports suggest that decreases in atmospheric nitrogen (N) deposition throughout Europe and North America may have resulted in declining nitrate export in surface waters in recent decades, yet it is unknown if and how terrestrial N cycling was affected. During a period of decreased atmospheric N deposition, we assessed changes in forest N cycling by evaluating trends in tree-ring δ15N values (between 1980 and 2010; n = 20 trees per watershed), stream nitrate yields (between 2000 and 2011), and retention of atmospherically-deposited N (between 2000 and 2011) in the North and South Tributaries (North and South, respectively) of Buck Creek in the Adirondack Mountains, USA. We hypothesized that tree-ring δ15N values would decline following decreases in atmospheric N deposition (after approximately 1995), and that trends in stream nitrate export and retention of atmospherically deposited N would mirror changes in tree-ring δ15N values. Three of the six sampled tree species and the majority of individual trees showed declining linear trends in δ15N for the period 1980–2010; only two individual trees showed increasing trends in δ15N values. From 1980 to 2010, trees in the watersheds of both tributaries displayed long-term declines in tree-ring δ15N values at the watershed scale (R = −0.35 and p = 0.001 in the North and R = −0.37 and p <0.001 in the South). The decreasing δ15N trend in the North was associated with declining stream nitrate concentrations (−0.009 mg N L−1 yr−1, p = 0.02), but no change in the retention of atmospherically deposited N was observed. In contrast, nitrate yields in the South did not exhibit a trend, and the watershed became less retentive of atmospherically deposited N (−7.3% yr−1, p < 0.001). Our δ15N results indicate a change in terrestrial N availability in both watersheds prior to decreases in atmospheric N deposition, suggesting that decreased atmospheric N deposition was not the sole driver of tree-ring δ15N values at these sites. Other factors, such as decreased sulfur deposition, disturbance, long-term successional trends, and/or increasing atmospheric CO2concentrations, may also influence trends in tree-ring δ15N values. Furthermore, declines in terrestrial N availability inferred from tree-ring δ15N values do not always correspond with decreased stream nitrate export or increased retention of atmospherically deposited N.
Controls on Nitrous Oxide Emissions from the Hyporheic Zones of Streams.
Quick, Annika M; Reeder, W Jeffery; Farrell, Tiffany B; Tonina, Daniele; Feris, Kevin P; Benner, Shawn G
2016-11-01
The magnitude and mechanisms of nitrous oxide (N 2 O) release from rivers and streams are actively debated. The complex interactions of hydrodynamic and biogeochemical controls on emissions of this important greenhouse gas preclude prediction of when and where N 2 O emissions will be significant. We present observations from column and large-scale flume experiments supporting an integrative model of N 2 O emissions from stream sediments. Our results show a distinct, replicable, pattern of nitrous oxide generation and consumption dictated by subsurface (hyporheic) residence times and biological nitrogen reduction rates. Within this model, N 2 O emission from stream sediments requires subsurface residence times (and microbially mediated reduction rates) be sufficiently long (and fast reacting) to produce N 2 O by nitrate reduction but also sufficiently short (or slow reacting) to limit N 2 O conversion to dinitrogen gas. Most subsurface exchange will not result in N 2 O emissions; only specific, intermediate, residence times (reaction rates) will both produce and release N 2 O to the stream. We also confirm previous observations that elevated nitrate and declining organic carbon reactivity increase N 2 O production, highlighting the importance of associated reaction rates in controlling N 2 O accumulation. Combined, these observations help constrain when N 2 O release will occur, providing a predictive link between stream geomorphology, hydrodynamics, and N 2 O emissions.
NASA Astrophysics Data System (ADS)
Wang, J.
2013-12-01
Nitrates are the most common type of groundwater contamination in agricultural regions. Environmental policies targeting nitrates have focused on input control (e.g., restricted fertilizer application), intermediate loads control (e.g., reduce nitrate leached from crop fields), and final loads control (e.g., reduce catchment nitrate loads). Nitrate loads can be affected by hydrological processes in both unsaturated and saturated zones. Although many of these processes have been extensively investigated in literature, they are commonly modeled as exogenous to farm management. A couple of recent studies by scientists from the Lawrence Livermore National Laboratory show that in some situations nitrate attenuation processes in the unsaturated/saturated zone, particularly denitrification, can be intensified by certain management practices to mitigate nitrate loads. Therefore, these nitrate attenuation processes can be regarded as a set of ecosystem services that farmers can take advantage of to reduce their cost of complying with environmental policies. In this paper, a representative California dairy farm is used as a case study to show how such ecosystem attenuation services can be framed within the farm owner's decision-making framework as an option for reducing groundwater nitrate contamination. I develop an integrated dynamic model, where the farmer maximizes discounted net farm profit over multiple periods subject to environmental regulations. The model consists of three submodels: animal-waste-crop, hydrologic, and economic model. In addition to common choice variables such as irrigation, fertilization, and waste disposal options, the farmer can also endogenously choose from three water sources: surface water, deep groundwater (old groundwater in the deep aquifer that is not affected by farm effluent in the short term), and shallow groundwater (drainage water that can be recycled via capture wells at the downstream end of the farm). The capture wells not only recycle wastewater, but can also increase the likelihood of denitrification. Thus the farmer essentially can choose whether, and to which extent, to install capture wells and take advantage of the ecosystem attenuation services. Decision rules from the dynamic optimization model demonstrate best management practices for the farm to improve its economic and environmental performance. I further use an economic valuation technique to value these services. Under the Millennium Ecosystem Assessment framework, nitrate attenuation in the unsaturated and saturated zone provides regulatory ecosystem services to humans, mainly nutrient regulation and waste treatment. With the integrated farm model, the production function approach is adopted to get the economic value of these regulatory services. The results highlight the significant role the environment can play in nitrate pollution control and potential benefits from designing policies that acknowledge this role. The most desirable policies are those that create incentive for farmers to use potential ecosystem services, which significantly reduce environmental compliance costs and increase social welfare.
Philip J. Riggan; Robert N. Lockwood; Ernest N. Lopez
1985-01-01
Atmospheric nitrogen deposition, associated with chronic urban air pollution, has produced stream water nitrate concentrations as high as 7.0 mg of N L-l in chaparral watersheds in the San Gabriel Mountains of Los Angeles County, CA. Stream water [NO3-] and discharge were greatest at high flow and may...
2012-07-01
technologies with significant capital costs, secondary waste streams, the involvement of hazardous materials, and the potential for additional worker...or environmental exposure. A more ideal technology would involve lower capital costs, would not generate secondary waste streams, would be...of bioaugmentation technology in general include low risk to human health and the environment during implementation, low secondary waste generation
Richard Venditti; Richard Gilbert; Andy Zhang; Said Abubakr
2000-01-01
Release liner waste material is found in post-consumer waste streams and is also a significant component of the preconsumer waste stream generated in the manufacturing of adhesive products. To date, very little has been reported pertaining to the behavior of release liner in paper recycling. In this study, the effect of the release liner material on the behavior of...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shott, Gregory
This special analysis (SA) evaluates whether the Materials and Energy Corporation (M&EC) Sealed Source waste stream (PERM000000036, Revision 0) is suitable for shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada National Security Site (NNSS). Disposal of the M&EC Sealed Source waste meets all U.S. Department of Energy (DOE) Manual DOE M 435.1-1, “Radioactive Waste Management Manual,” Chapter IV, Section P performance objectives (DOE 1999). The M&EC Sealed Source waste stream is recommended for acceptance without conditions.
The Effect of Restored and Native Oxbows on Hydraulic Loads ...
The use of oxbow wetlands has been identified as a potential strategy to reduce nutrient transport from agricultural drainage tiles to streams in Iowa. In 2013 and 2014, a study was conducted in north central Iowa in a native oxbow in the Lyons Creek watershed and two reconstructed oxbows in the Prairie Creek watershed (Smeltzer west and Smeltzer east) to assess their effectiveness at reducing nitrogen and phosphorus loads. The tile line inlets carrying agricultural runoff to the oxbows, the outfall from the oxbows and the surface waters in the streams receiving the outfall water were monitored for discharge and nutrients from February 2013 to September 2015. Smeltzer west and east also had four monitoring wells each, two in the upland and two between the oxbow and Prairie Creek to monitor surface water groundwater interaction. The Smeltzer west and east oxbow sites also were instrumented to continuously measure the nitrate concentration. Rainfall was measured at one Lyons Creek and one Smeltzer site. Daily mean nitrate-N concentrations in Lyons Creek in 2013 ranged from 41 mg/L to 11.8 mg/L, the median daily mean nitrate-N concentration was 33 mg/L. Daily mean nitrate-N concentrations in Prairie Creek in 2013 ranged from 15.0 mg/L to 32 mg/L in June. The median daily mean nitrate-N concentration for the sampled period was 11.2 mg/L. In 2014, daily mean nitrate-N concentrations in Prairie Creek ranged from 0.17 mg/L to 26.7 mg/L in July; the daily mean
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cozzi, Alex D.; McCabe, Daniel J.
The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Melter Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream during full WTP operations is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. However, during the Direct Feed LAW (DFLAW) scenario, planned disposition of this stream is to evaporate it in a new evaporator in the Effluent Management Facility (EMF) and then return it to themore » LAW melter. It is important to understand the composition of the effluents from the melter and new evaporator so that the disposition of these streams can be accurately planned and accommodated. Furthermore, alternate disposition of this stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Alternate disposition would also eliminate this stream from recycling within WTP when it begins operations and would decrease the LAW vitrification mission duration and quantity of glass waste. This LAW Melter Off-Gas Condensate stream will contain components that are volatile at melter temperatures and are problematic for the glass waste form, such as halides and sulfate, along with entrained, volatile, and semi-volatile metals, such as Hg, As, and Se. Because this stream will recycle within WTP, these components accumulate in the Melter Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Diverting the stream reduces the halides and sulfate that get recycled to the melter, and is a key objective of this work. This overall program examines the potential treatment and immobilization of this stream to enable alternative disposal. The objective of earlier tasks was to formulate and prepare a simulant of the LAW Melter Off-gas Condensate expected during DFLAW operations and use it in evaporator testing to predict the composition of the effluents from the Effluent Management Facility (EMF) evaporator to aid in planning for their disposition. The objective of this task was to test immobilization options for this evaporator bottoms aqueous stream. This document describes the method used to formulate a simulant of this EMF evaporator bottoms stream, immobilize it, and determine if the immobilized waste forms meet disposal criteria.« less
An overview of nitrate sources and operating processes in arid and semiarid aquifer systems.
Gutiérrez, Mélida; Biagioni, Richard N; Alarcón-Herrera, Maria Teresa; Rivas-Lucero, Bertha A
2018-05-15
Nitrate concentration in most aquifers in arid and semi-arid areas has increased in the past several decades as a result of human activities. Under the predominantly oxic conditions of these aquifers, denitrification is inhibited, allowing nitrate, a soluble and stable form of nitrogen (N), to accumulate. Because of its close association with municipal and agricultural wastes, nitrate is commonly used as an indicator of anthropogenic contamination. Aquifers affected by agricultural waste may contain salts from irrigation returns and herbicides in addition to nitrates. Preventing leakage from soil to deeper parts of the aquifer is thus a priority in the sustainable management of aquifers in arid and semiarid areas. Studies report a wide range of nitrate concentrations distributed non-uniformly within the aquifer, with roughly 40% and 20% of sampled wells exceeding 50mg/L nitrate in shallow and deep parts of the aquifer respectively. In aquifers at risk of becoming contaminated, nitrate isotopes (δ 15 N, δ 18 O, Δ 17 O) can be used to identify the source of nitrogen as mineral or organic fertilizer, sewage, or atmospheric deposition. A variety of mathematical models (crop, hydrological, geochemical, or a combination of them) have been successful in identifying best practices that minimize N leakage without negatively affecting crop yield. In addition, field research in crop management, e.g., conservation agriculture, has yielded promising results in determining the adequate dosage and time of application of fertilizers to reduce N losses. Examples of key dryland aquifers impacted by nitrate are discussed, and some of the most pressing challenges to achieve sustainability are presented. Copyright © 2017 Elsevier B.V. All rights reserved.
Electrodialysis-based separation process for salt recovery and recycling from waste water
Tsai, S.P.
1997-07-08
A method for recovering salt from a process stream containing organic contaminants is provided, comprising directing the waste stream to a desalting electrodialysis unit so as to create a concentrated and purified salt permeate and an organic contaminants-containing stream, and contacting said concentrated salt permeate to a water-splitting electrodialysis unit so as to convert the salt to its corresponding base and acid. 6 figs.
Electrodialysis-based separation process for salt recovery and recycling from waste water
Tsai, Shih-Perng
1997-01-01
A method for recovering salt from a process stream containing organic contaminants is provided, comprising directing the waste stream to a desalting electrodialysis unit so as to create a concentrated and purified salt permeate and an organic contaminants containing stream, and contacting said concentrated salt permeate to a water-splitting electrodialysis unit so as to convert the salt to its corresponding base and acid.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mauriello, P.J.; Ragbeer, D.
1997-12-01
In the wake of the U.S. Supreme Court decision in the Carbone vs. Clarkstown case striking down waste flow control as unconstitutional, Dade County, Florida, one of the most severely impacted communities in the nation, has managed to stabilize its waste stream and balance its solid waste department finances; although the road taken to restabilization has been a difficult one. At its peak in 1995, Dade County experienced an annual loss of solid waste in excess of 1,000,000 tons, or over 40 percent of the waste stream normally handled by the County. This diversion of waste was accompanied by amore » net revenue loss of $30 million per year. The County lost its ability to plan for future capacity needs, or to assure sufficient future waste flows to meet its put-or-pay obligation to the County`s Resources Recovery plant operator. The County`s solid waste management system bonds were downgraded by Moody`s Investors Service and Standard and Poors. With the help of a special solid waste management team, appointed by the County Manager, the department was able to rightsize its waste disposal operations to fit its reduced waste flows, stabilize its waste stream, and develop strategies to solve its long-term funding shortfall.« less
On the use of coprostanol to identify source of nitrate pollution in groundwater
NASA Astrophysics Data System (ADS)
Nakagawa, Kei; Amano, Hiroki; Takao, Yuji; Hosono, Takahiro; Berndtsson, Ronny
2017-07-01
Investigation of contaminant sources is indispensable for developing effective countermeasures against nitrate (NO3-) pollution in groundwater. Known major nitrogen (N) sources are chemical fertilizers, livestock waste, and domestic wastewater. In general, scatter diagrams of δ18O and δ15N from NO3- can be used to identify these pollution sources. However, this method can be difficult to use for chemical fertilizers and livestock waste sources due to the overlap of δ18O and δ15N ranges. In this study, we propose to use coprostanol as an indicator for the source of pollution. Coprostanol can be used as a fecal contamination indicator because it is a major fecal sterol formed by the conversion of cholesterol by intestinal bacteria in the gut of higher animals. The proposed method was applied to investigate NO3- pollution sources for groundwater in Shimabara, Nagasaki, Japan. Groundwater samples were collected at 33 locations from March 2013 to November 2015. These data were used to quantify relationships between NO3-N, δ15N-NO3-, δ18O-NO3-, and coprostanol. The results show that coprostanol has a potential for source identification of nitrate pollution. For lower coprostanol concentrations (<30 ng L-1) in the nitrate-polluted group, fertilizer is likely to be the predominant source of NO3-. However, higher concentration coprostanol samples in the nitrate-polluted group can be related to pollution from livestock waste. Thus, when conventional diagrams of isotopic ratios cannot distinguish pollution sources, coprostanol may be a useful tool.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reigel, M.; Johnson, F.; Crawford, C.
2011-09-20
The U.S. Department of Energy (DOE), Office of River Protection (ORP), is responsible for the remediation and stabilization of the Hanford Site tank farms, including 53 million gallons of highly radioactive mixed wasted waste contained in 177 underground tanks. The plan calls for all waste retrieved from the tanks to be transferred to the Waste Treatment Plant (WTP). The WTP will consist of three primary facilities including pretreatment facilities for Low Activity Waste (LAW) to remove aluminum, chromium and other solids and radioisotopes that are undesirable in the High Level Waste (HLW) stream. Removal of aluminum from HLW sludge canmore » be accomplished through continuous sludge leaching of the aluminum from the HLW sludge as sodium aluminate; however, this process will introduce a significant amount of sodium hydroxide into the waste stream and consequently will increase the volume of waste to be dispositioned. A sodium recovery process is needed to remove the sodium hydroxide and recycle it back to the aluminum dissolution process. The resulting LAW waste stream has a high concentration of aluminum and sodium and will require alternative immobilization methods. Five waste forms were evaluated for immobilization of LAW at Hanford after the sodium recovery process. The waste forms considered for these two waste streams include low temperature processes (Saltstone/Cast stone and geopolymers), intermediate temperature processes (steam reforming and phosphate glasses) and high temperature processes (vitrification). These immobilization methods and the waste forms produced were evaluated for (1) compliance with the Performance Assessment (PA) requirements for disposal at the IDF, (2) waste form volume (waste loading), and (3) compatibility with the tank farms and systems. The iron phosphate glasses tested using the product consistency test had normalized release rates lower than the waste form requirements although the CCC glasses had higher release rates than the quenched glasses. However, the waste form failed to meet the vapor hydration test criteria listed in the WTP contract. In addition, the waste loading in the phosphate glasses were not as high as other candidate waste forms. Vitrification of HLW waste as borosilicate glass is a proven process; however the HLW and LAW streams at Hanford can vary significantly from waste currently being immobilized. The ccc glasses show lower release rates for B and Na than the quenched glasses and all glasses meet the acceptance criterion of < 4 g/L. Glass samples spiked with Re{sub 2}O{sub 7} also passed the PCT test. However, further vapor hydration testing must be performed since all the samples cracked and the test could not be performed. The waste loading of the iron phosphate and borosilicate glasses are approximately 20 and 25% respectively. The steam reforming process produced the predicted waste form for both the high and low aluminate waste streams. The predicted waste loadings for the monolithic samples is approximately 39%, which is higher than the glass waste forms; however, at the time of this report, no monolithic samples were made and therefore compliance with the PA cannot be determined. The waste loading in the geopolymer is approximately 40% but can vary with the sodium hydroxide content in the waste stream. Initial geopolymer mixes revealed compressive strengths that are greater than 500 psi for the low aluminate mixes and less than 500 psi for the high aluminate mixes. Further work testing needs to be performed to formulate a geopolymer waste form made using a high aluminate salt solution. A cementitious waste form has the advantage that the process is performed at ambient conditions and is a proven process currently in use for LAW disposal. The Saltstone/Cast Stone formulated using low and high aluminate salt solutions retained at least 97% of the Re that was added to the mix as a dopant. While this data is promising, additional leaching testing must be performed to show compliance with the PA. Compressive strength tests must also be performed on the Cast Stone monoliths to verify PA compliance. Based on testing performed for this report, the borosilicate glass and Cast Stone are the recommended waste forms for further testing. Both are proven technologies for radioactive waste disposal and the initial testing using simulated Hanford LAW waste shows compliance with the PA. Both are resistant to leaching and have greater than 25% waste loading.« less
Pilot-scale vadose zone microbial biobarriers removed nitrate leaching from a cattle corral
USDA-ARS?s Scientific Manuscript database
activities that involve animal wastes can result in the contamination of subsurface soils by nitrates. In saturated or nearly saturated soils microbial biobarriers are a common method used to remove contaminants from water. This field study was conducted beneath a cattle pen in northeast Colorado a...
Waste streams in a typical crewed space habitat: An update
NASA Technical Reports Server (NTRS)
Golub, M. A.; Wydeven, T.
1992-01-01
A compilation of generation rates and chemical compositions of potential waste streams in a typical crewed space habitat, reported in a prior NASA Technical Memorandum and a related journal article, was updated. This report augments that compilation by the inclusion of the following new data: those data uncovered since completion of the prior report; those obtained from Soviet literature relevant to life support issues; and those for various minor human body wastes not presented previously (saliva, flatus, hair, finger- and toenails, dried skin and skin secretions, tears, and semen), but included here for purposes of completeness. These waste streams complement those discussed previously: toilet waste (urine, feces, etc.), hygiene water (laundry, shower/handwash, dishwasher water and cleansing agents), trash, humidity condensate, perspiration and respiration water, trace contaminants, and dust generation. This report also reproduces the latest information on the environmental control and life support system design parameters for Space Station Freedom.
Cattle waste tops cars as source of Southern California smog
NASA Astrophysics Data System (ADS)
Schultz, Colin
2012-06-01
A new study shows that cows, not cars, are the more substantial source of ammonia that leads to ammonium nitrate in California's South Coast Air Basin, the smoggiest place in the United States. Within the region, which consists of the area surrounding and downwind of Los Angeles, a large proportion of the fine-grained particulate matter that makes up smog is formed from ammonium nitrate. Nowak et al. found two main sources of ammonium nitrate: small gas-powered vehicles and dairy farms. Catalytic converters designed to stem the emissions of carbon monoxide, nitrogen oxides, and hydrocarbons from the region's 9.9 million vehicles can produce gaseous ammonia as an unwanted by-product. Bacteria decomposing organic wastes from the region's 298,000 dairy cattle, on the other hand, also account for a sizable source of ammonia emissions.
Forecasting waste compositions: A case study on plastic waste of electronic display housings.
Peeters, Jef R; Vanegas, Paul; Kellens, Karel; Wang, Feng; Huisman, Jaco; Dewulf, Wim; Duflou, Joost R
2015-12-01
Because of the rapid succession of technological developments, the architecture and material composition of many products used in daily life have drastically changed over the last decades. As a result, well-adjusted recycling technologies need to be developed and installed to cope with these evolutions. This is essential to guarantee continued access to materials and to reduce the ecological impact of our material consumption. However, limited information is currently available on the material composition of arising waste streams and even less on how these waste streams will evolve. Therefore, this paper presents a methodology to forecast trends in the material composition of waste streams. To demonstrate the applicability and value of the proposed methodology, it is applied to forecast the evolution of plastic housing waste from flat panel display (FPD) TVs, FPD monitors, cathode ray tube (CRT) TVs and CRT monitors. The results of the presented forecasts indicate that a wide variety of plastic types and additives, such as flame retardants, are found in housings of similar products. The presented case study demonstrates that the proposed methodology allows the identification of trends in the evolution of the material composition of waste streams. In addition, it is demonstrated that the recycling sector will need to adapt its processes to deal with the increasing complexity of plastics of end-of-life electronic displays while respecting relevant directives. Copyright © 2015 Elsevier Ltd. All rights reserved.
Evaluation of actinide biosorption by microorganisms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Happel, A.M.
1996-06-01
Conventional methods for removing metals from aqueous solutions include chemical precipitation, chemical oxidation or reduction, ion exchange, reverse osmosis, electrochemical treatment and evaporation. The removal of radionuclides from aqueous waste streams has largely relied on ion exchange methods which can be prohibitively costly given increasingly stringent regulatory effluent limits. The use of microbial cells as biosorbants for heavy metals offers a potential alternative to existing methods for decontamination or recovery of heavy metals from a variety of industrial waste streams and contaminated ground waters. The toxicity and the extreme and variable conditions present in many radionuclide containing waste streams maymore » preclude the use of living microorganisms and favor the use of non-living biomass for the removal of actinides from these waste streams. In the work presented here, we have examined the biosorption of uranium by non-living, non-metabolizing microbial biomass thus avoiding the problems associated with living systems. We are investigating biosorption with the long term goal of developing microbial technologies for the remediation of actinides.« less
NASA Astrophysics Data System (ADS)
Sigler, W. A.; Ewing, S. A.; Payn, R. A.; Jones, C. A.; Brookshire, J.; Klassen, J. K.; Jackson-Smith, D.; Weissmann, G. S.
2016-12-01
Shallow aquifers impaired by nitrate from agriculture are widespread and remediation or prevention of this problem requires understanding of N leaching rates at a variety of spatial scales. Characterization of the drivers of nitrate leaching at an intermediate scale (103 to 105 ha) is needed to bridge from field scale observations to the landscape-scale context, allowing informed water resource management decisions. Here we explore patterns in nitrate leaching rates across a depositional landform with a predominant land use of non-irrigated small grain production in the Northern Great Plains within the Upper Missouri Basin. The shallow Moccasin terrace (260,000 ha) aquifer is bounded in vertical extent by underlying shale and is isolated from mountain front stream recharge, such that aquifer recharge is dominated by infiltration of precipitation through agricultural soils. We leverage this simplified landform scale water balance to estimate leaching rates using groundwater nitrate concentrations and surface water discharge, and quantify uncertainty using a Monte Carlo approach based on spatial variation in groundwater nitrate concentrations. Landform-scale nitrate-N leaching rates ranged between 10 and 24 kg ha-1 yr-1 during 2012-2014 across two terrace catchments. These rates represent 11 to 27% of fertilizer application rates but are likely derived from a combination of soil organic N mineralization and direct fertilizer loss. While groundwater apparent age is relatively young (0-5 y) based on tritium-helium analysis, whole-aquifer turnover time calculations are an order of magnitude longer (20-23 y), suggesting aquifer heterogeneity and thus a longer potential response time to management changes than suggested by tracer-based aging. We collaborated with local producers to undertake this work, and discussed our results with community members throughout the study. Based on a follow-up survey, producers are now more likely to consider nitrate leaching when making management decisions, suggesting that location-specific producer engagement can facilitate practical solutions to non-point source water quality issues.
Liquid secondary waste. Waste form formulation and qualification
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cozzi, A. D.; Dixon, K. L.; Hill, K. A.
The Hanford Site Effluent Treatment Facility (ETF) currently treats aqueous waste streams generated during Site cleanup activities. When the Hanford Tank Waste Treatment and Immobilization Plant (WTP) begins operations, a liquid secondary waste (LSW) stream from the WTP will need to be treated. The volume of effluent for treatment at the ETF will increase significantly. Washington River Protection Solutions is implementing a Secondary Liquid Waste Immobilization Technology Development Plan to address the technology needs for a waste form and solidification process to treat the increased volume of waste planned for disposal at the Integrated Disposal Facility IDF). Waste form testingmore » to support this plan is composed of work in the near term to demonstrate the waste form will provide data as input to a performance assessment (PA) for Hanford’s IDF.« less
Gray, John E.; Stillings, Lisa L.
2003-01-01
Mercury and methylmercury concentrations were measured in mine wastes, stream sediments, and stream waters collected both proximal and distal from abandoned mercury mines to evaluate mercury contamination and mercury methylation in the Humboldt River system. The climate in the study area is arid, and due to the lack of mine-water runoff, water-leaching laboratory experiments were used to evaluate the potential of mine wastes to release mercury. Mine-waste calcine contains mercury concentrations as high as 14,000 ?g/g. Stream-sediment samples collected within 1 km of the mercury mines studied contain mercury concentrations as high as 170 ?g/g, but sediments collected from the Humboldt River and regional baseline sites have much lower mercury contents, less than 0.44 ?g/g. Similarly, methylmercury concentrations in mine-waste calcine are locally as high as 96 ng/g, but methylmercury contents in stream sediments collected down-stream from the mines and from the Humboldt River are lower (<0.05-0.95 ng/g). Stream-water samples collected below two mines studied contain mercury concentrations ranging from 6 to 2,000 ng/L, whereas mercury contents in Humboldt River and Rye Patch Reservoir water were generally lower, ranging from 2.1 to 9.0 ng/L. Methylmercury concentrations in Humboldt River system water were the lowest in this study (<0.02- 0.27 ng/L). Although mercury and methylmercury concentrations were elevated in some mine-waste calcine and mercury concentrations were locally high in mine-waste leachate samples, data show significant dilution of mercury and lower mercury methylation down gradient from the mines, especially in the sediments and water collected from the Humboldt River, which is more than 8 km from any mercury mines. Data show only minor, local transference of mercury and methylmercury from mine-waste calcine to stream sediment, and then onto the water column, and indicate little transference of mercury from the mine sites to the Humboldt River system.
Household hazardous waste management: a review.
Inglezakis, Vassilis J; Moustakas, Konstantinos
2015-03-01
This paper deals with the waste stream of household hazardous waste (HHW) presenting existing management systems, legislation overview and other relevant quantitative and qualitative information. European Union legislation and international management schemes are summarized and presented in a concise manner by the use of diagrams in order to provide crucial information on HHW. Furthermore, sources and types, numerical figures about generation, collection and relevant management costs are within the scope of the present paper. The review shows that the term used to refer to hazardous waste generated in households is not clearly defined in legislation, while there is absence of specific acts regulating the management of HHW. The lack of obligation to segregate HHW from the household waste and the different terminology used makes it difficult to determine the quantities and composition of this waste stream, while its generation amount is relatively small and, therefore, is commonly overlooked in waste statistics. The paper aims to cover the gap in the related literature on a subject that is included within the crucial waste management challenges at world level, considering that HHW can also have impact on other waste streams by altering the redox conditions or causing direct reactions with other non hazardous waste substances. Copyright © 2014 Elsevier Ltd. All rights reserved.
Solid recovered fuel: An experiment on classification and potential applications.
Bessi, C; Lombardi, L; Meoni, R; Canovai, A; Corti, A
2016-01-01
The residual urban waste of Prato district (Italy) is characterized by a high calorific value that would make it suitable for direct combustion in waste-to-energy plants. Since the area of central Italy lacks this kind of plant, residual municipal waste is quite often allocated to mechanical treatment plants in order to recover recyclable materials (such as metals) and energy content, sending the dry fractions to waste-to-energy plants outside the region. With the previous Italian legislation concerning Refuse Derived Fuels, only the dry stream produced as output by the study case plant, considered in this study, could be allocated to energy recovery, while the other output flows were landfilled. The most recent Italian regulation, introduced a new classification for the fuel streams recovered from waste following the criteria of the European standard (EN 15359:2011), defining the Solid Recovered Fuel (SRF). In this framework, the aim of this study was to check whether the different streams produced as output by the study case plant could be classified as SRF. For this reason, a sampling and analysis campaign was carried out with the purpose of characterizing every single output stream that can be obtained from the study case mechanical treatment plant, when operating it in different ways. The results showed that all the output flows from the study case mechanical treatment plant were classified as SRF, although with a wide quality range. In particular, few streams, of rather poor quality, could be fed to waste-to-energy plants, compatibly with the plant feeding systems. Other streams, with very high quality, were suitable for non-dedicated facilities, such as cement plants or power plants, as a substitute for coal. The implementation of the new legislation has hence the potential for a significant reduction of landfilling, contributing to lowering the overall environmental impact by avoiding the direct impacts of landfilling and by exploiting the beneficial effects of energy recovery from waste. Copyright © 2015 Elsevier Ltd. All rights reserved.
Regional Monitoring of Acidic Lakes and Streams
This asset provides data on the acid-base status of lakes and streams. Key chemical indicators measured include: sulfate, nitrate, ammonium, chloride, Acid Neutralizing Capacity (ANC), pH, base cations, dissolved organic carbon (DOC), total aluminum. TIME and LTM are part of EPA's Environmental Monitoring and Assessment Program (EMAP). Long-term monitoring of the acid-base status (pH, ANC, SO4, NO3, NH4, DOC, base cations, Al) in lakes and streams. Monitoring is conducted in acid sensitive regions of the Eastern U.S.
Method for removal of nitrogen oxides from stationary combustion sources
NASA Technical Reports Server (NTRS)
Cooper, Charles D. (Inventor); Collins, Michelle M. (Inventor); Clausen, III, Christian A. (Inventor)
2004-01-01
A method for removing NO.sub.X from gas streams emanating from stationary combustion sources and manufacturing plants utilizes the injection of hydrogen peroxide into the gas stream for rapid gas-phase oxidation of NO to NO.sub.2 and water-soluble nitrogen acids HNO.sub.2 and HNO.sub.3. The nitrogen acids may be removed from the oxidized gas stream by wet scrubbing or by contact with a particulate alkaline material to form a nitrite/nitrate salt.
Quantification and probabilistic modeling of CRT obsolescence for the State of Delaware.
Schumacher, Kelsea A; Schumacher, Thomas; Agbemabiese, Lawrence
2014-11-01
The cessation of production and replacement of cathode ray tube (CRT) displays with flat screen displays have resulted in the proliferation of CRTs in the electronic waste (e-waste) recycle stream. However, due to the nature of the technology and presence of hazardous components such as lead, CRTs are the most challenging of electronic components to recycle. In the State of Delaware it is due to this challenge and the resulting expense combined with the large quantities of CRTs in the recycle stream that electronic recyclers now charge to accept Delaware's e-waste. Therefore it is imperative that the Delaware Solid Waste Authority (DSWA) understand future quantities of CRTs entering the waste stream. This study presents the results of an assessment of CRT obsolescence in the State of Delaware. A prediction model was created utilizing publicized sales data, a variety of lifespan data as well as historic Delaware CRT collection rates. Both a deterministic and a probabilistic approach using Monte Carlo Simulation (MCS) were performed to forecast rates of CRT obsolescence to be anticipated in the State of Delaware. Results indicate that the peak of CRT obsolescence in Delaware has already passed, although CRTs are anticipated to enter the waste stream likely until 2033. Copyright © 2014 Elsevier Ltd. All rights reserved.
Redesigning Urban Carbon Cycles: from Waste Stream to Commodity
NASA Astrophysics Data System (ADS)
Brabander, D. J.; Fitzstevens, M. G.
2013-12-01
While there has been extensive research on the global scale to quantify the fluxes and reservoirs of carbon for predictive climate change models, comparably little attention has been focused on carbon cycles in the built environment. The current management of urban carbon cycles presents a major irony: while cities produce tremendous fluxes of organic carbon waste, their populations are dependent on imported carbon because most urban have limited access to locally sourced carbon. The persistence of outdated management schemes is in part due to the fact that reimagining the handling of urban carbon waste streams requires a transdisciplinary approach. Since the end of the 19th century, U.S. cities have generally relied on the same three options for managing organic carbon waste streams: burn it, bury it, or dilute it. These options still underpin the framework for today's design and management strategies for handling urban carbon waste. We contend that urban carbon management systems for the 21st century need to be scalable, must acknowledge how climate modulates the biogeochemical cycling of urban carbon, and should carefully factor local political and cultural values. Urban waste carbon is a complex matrix ranging from wastewater biosolids to municipal compost. Our first goal in designing targeted and efficient urban carbon management schemes has been examining approaches for categorizing and geochemically fingerprinting these matrices. To date we have used a combination of major and trace element ratio analysis and bulk matrix characteristics, such as pH, density, and loss on ignition, to feed multivariable statistical analysis in order to identify variables that are effective tracers for each waste stream. This approach was initially developed for Boston, MA, US, in the context of identifying components of municipal compost streams that were responsible for increasing the lead inventory in the final product to concentrations that no longer permitted its use in supporting urban agriculture. We are now extending this approach to additional large U.S. and European urban centers where different philosophical and technological approaches to managing urban waste carbon have resulted in a range of infrastructures, from highly distributed systems (Germany) to centralized mega facilities (London). Ultimately, this research will lead to a decision-making matrix model that will permit cities to customize their urban carbon waste stream facilities and transform this waste into a usable commodity.
Analysis of Nitrogen Cycling in a Forest Stream During Autumn Using a 15N Tracer Addition
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tank, J.L.
2000-01-01
We added {sup 15}NH{sub 4}Cl over 6 weeks to Upper Ball Creek, a second-order deciduous forest stream in the Appalachian Mountains, to follow the uptake, spiraling, and fate of nitrogen in a stream food web during autumn. A priori predictions of N flow and retention were made using a simple food web mass balance model. Values of d{sup 15}N were determined for stream water ammonium, nitrate, dissolved organic nitrogen, and various compartments of the food web over time and distance and then compared to model predictions.
Method for extracting metals from aqueous waste streams for long term storage
Chaiko, D.J.
1995-03-07
A liquid-liquid extraction method for removing metals and hydrous metal colloids from waste streams is provided wherein said waste streams are contacted with a solvent system containing a water-in-oil microemulsion wherein the inverted micelles contain the extracted metal. A silicon alkoxide, either alone or in combination with other metal alkoxide compounds is added to the water-in-oil microemulsion, thereby allowing encapsulation of the extracted metal within a silicon oxide network. Lastly, the now-encapsulated metal is precipitated from the water-in-oil microemulsion phase to yield aggregates of metal-silicate particles having average individual particle sizes of approximately 40 nanometers. 2 figs.
Method for extracting metals from aqueous waste streams for long term storage
Chaiko, D.J.
1993-01-01
A liquid-liquid extraction method for removing metals and hydrous metal colloids from waste streams is provided wherein said waste streams are contacted with a solvent system containing a water-in-oil microemulsion wherein the inverted micelles contain the extracted metal. A silicon alkoxide, either alone or in combination with other metal alkoxide compounds is added to the water-in-oil microemulsion, thereby allowing encapsulation of the extracted metal within a silicon oxide network. Lastly, the now-encapsulated metal is precipitated from the water-in-oil microemulsion phase to yield aggregates of metal-silicate particles having average. individual particle sizes of approximately 40 manometers.
Method for extracting metals from aqueous waste streams for long term storage
Chaiko, David J.
1995-01-01
A liquid--liquid extraction method for removing metals and hydrous metal colloids from waste streams is provided wherein said waste streams are contacted with a solvent system containing a water-in-oil microemulsion wherein the inverted micelles contain the extracted metal. A silicon alkoxide, either alone or in combination with other metal alkoxide compounds is added to the water-in-oil microemulsion, thereby allowing encapsulation of the extracted metal within a silicon oxide network. Lastly, the now-encapsulated metal is precipitated from the water-in-oil microemulsion phase to yield aggregates of metal-silicate particles having average individual particle sizes of approximately 40 nanometers.
Approaches to resource recovery in controlled ecological life support systems
NASA Technical Reports Server (NTRS)
Bubenheim, D. L.; Wydeven, T.
1994-01-01
Recovery of resources from waste streams in a space habitat is essential to minimize the resupply burden and achieve self sufficiency. The ultimate goal of a Controlled Ecological Life Support System (CELSS) is to achieve the greatest practical level of mass recycle and provide self sufficiency and safety for humans. Several mission scenarios leading to the ultimate application could employ CELSS component technologies or subsystems with initial emphasis on recycle of the largest mass components of the waste stream. Candidate physical/chemical and biological processes for resource recovery from liquid and solid waste streams are discussed and the current fundamental recovery potentials are estimated.
Climate change mitigation for agriculture: water quality benefits and costs.
Wilcock, Robert; Elliott, Sandy; Hudson, Neale; Parkyn, Stephanie; Quinn, John
2008-01-01
New Zealand is unique in that half of its national greenhouse gas (GHG) inventory derives from agriculture--predominantly as methane (CH4) and nitrous oxide (N2O), in a 2:1 ratio. The remaining GHG emissions predominantly comprise carbon dioxide (CO2) deriving from energy and industry sources. Proposed strategies to mitigate emissions of CH4 and N2O from pastoral agriculture in New Zealand are: (1) utilising extensive and riparian afforestation of pasture to achieve CO2 uptake (carbon sequestration); (2) management of nitrogen through budgeting and/or the use of nitrification inhibitors, and minimizing soil anoxia to reduce N2O emissions; and (3) utilisation of alternative waste treatment technologies to minimise emissions of CH4. These mitigation measures have associated co-benefits and co-costs (disadvantages) for rivers, streams and lakes because they affect land use, runoff loads, and receiving water and habitat quality. Extensive afforestation results in lower specific yields (exports) of nitrogen (N), phosphorus (P), suspended sediment (SS) and faecal matter and also has benefits for stream habitat quality by improving stream temperature, dissolved oxygen and pH regimes through greater shading, and the supply of woody debris and terrestrial food resources. Riparian afforestation does not achieve the same reductions in exports as extensive afforestation but can achieve reductions in concentrations of N, P, SS and faecal organisms. Extensive afforestation of pasture leads to reduced water yields and stream flows. Both afforestation measures produce intermittent disturbances to waterways during forestry operations (logging and thinning), resulting in sediment release from channel re-stabilisation and localised flooding, including formation of debris dams at culverts. Soil and fertiliser management benefits aquatic ecosystems by reducing N exports but the use of nitrification inhibitors, viz. dicyandiamide (DCD), to achieve this may under some circumstances impair wetland function to intercept and remove nitrate from drainage water, or even add to the overall N loading to waterways. DCD is water soluble and degrades rapidly in warm soil conditions. The recommended application rate of 10 kg DCD/ha corresponds to 6 kg N/ha and may be exceeded in warm climates. Of the N2O produced by agricultural systems, approximately 30% is emitted from indirect sources, which are waterways draining agriculture. It is important therefore to focus strategies for managing N inputs to agricultural systems generally to reduce inputs to wetlands and streams where these might be reduced to N2O. Waste management options include utilizing the CH4 resource produced in farm waste treatment ponds as a source of energy, with conversion to CO2 via combustion achieving a 21-fold reduction in GHG emissions. Both of these have co-benefits for waterways as a result of reduced loadings. A conceptual model derived showing the linkages between key land management practices for greenhouse gas mitigation and key waterway values and ecosystem attributes is derived to aid resource managers making decisions affecting waterways and atmospheric GHG emissions. Copyright (c) IWA Publishing 2008.
Selected nutrients and pesticides in streams of the eastern Iowa basins, 1970-95
Schnoebelen, Douglas J.; Becher, Kent D.; Bobier, Matthew W.; Wilton, Thomas
1999-01-01
The statistical analysis of the nutrient data typically indicated a strong positive correlation of nitrate with streamflow. Total phosphorus concentrations with streamflow showed greater variability than nitrate, perhaps reflecting the greater potential of transport of phosphorus on sediment rather than in the dissolved phase as with nitrate. Ammonia and ammonia plus organic nitrogen showed no correlation with streamflow or a weak positive correlation. Seasonal variations and the relations of nutrients and pesticides to streamflow generally corresponded with nonpoint‑source loadings, although possible point sources for nutrients were indicated by the data at selected monitoring sites. Statistical trend tests for concentrations and loads were computed for nitrate, ammonia, and total phosphorus. Trend analysis indicated decreases for ammonia and total phosphorus concentrations at several sites and increases for nitrate concentrations at other sites in the study unit.
Industrial wastes and public health: some historical notes, Part I, 1876-1932.
Tarr, J A
1985-01-01
This article has focused on the relatively low priority accorded industrial wastes compared to human wastes by the public health community in the period from 1876 through 1932. The critical reason for this prioritization was the potential for acute health effects from human wastes as compared with the belief that industrial wastes had only indirect effects. State departments of health normally only responded to industrial wastes when they endangered the potable nature of water supplies or interfered with water and sewage treatment processes. Within the public health community, however, a relatively small group of interdisciplinary professionals argued for attention to the indirect health effects of industrial wastes and their impacts on the total stream environment. In conjunction with other groups interested in clean streams--such as sportsmen and manufacturers who required high quality process water--they pushed for a broader state legislative mandate in regard to pollution control. Some states created new bureaus or boards with responsibility for industrial wastes and the larger stream environment but the attack on industrial pollution remained limited in this period. The final significant development regarding industrial pollution and public health concerned the formulation by Streeter-Phelps of the Public Health Service of a theory of stream purification with a set of general quantitative indicators. This application was of particular importance in regard to the high-oxygen consuming nature of organic industrial wastes and the wide variety of effluents that existed. Industrial wastes constituted what Harvey Brooks, in his essay "Science Indicators and Science Priorities" calls a very "messy" research problem--one that does "not lend itself to elegant and widely applicable generalizations."(ABSTRACT TRUNCATED AT 250 WORDS) Images p1061-a p1061-b p1063-a p1065-a PMID:3895993
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1994-08-01
As part of the original Hanford Federal Facility Agreement and Concent Order negotiations, US DOE, US EPA and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground to the Hanford Site are subject to permitting in the State Waste Discharge Permit Program (SWDP). This document constitutes the SWDP Application for the 200 Area TEDF stream which includes the following streams discharged into the area: Plutonium Finishing Plant waste water; 222-S laboratory Complex waste water; T Plant waste water; 284-W Power Plant waste water; PUREX chemical Sewer; B Plant chemical sewer, process condensate, steam condensate; 242-A-81more » Water Services waste water.« less