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Sample records for agricultural subsurface drainage

  1. Hydrologic Impact Of Subsurface Drainage Of Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Naz, B. S.; Johannsen, C. J.; Bowling, L. C.

    2005-12-01

    Although subsurface drainage has benefited agricultural productions in many regions of the U.S., there are also concerns about the potential impacts of these systems on watershed hydrology and water quality. This study was focused on tile lines identification and hydrologic response of subsurface drainage systems for the Agronomy Center for Research and Education (ACRE), West Lafayette, Indiana and the Southeastern Purdue Agriculture Center (SEPAC) in southeastern, Indiana. The purpose of the study was to develop and evaluate a remote sensing methodology for automatic detection of tile lines from aerial photographs and to evaluate the Distributed Hydrology Soil-Vegetation Model (DHSVM) to analyze the hydrologic response of tile drained fields. A step-wise approach was developed to first use different image enhancement techniques to increase the visual distinction of tile lines from other details in the image. A new classification model was developed to identify locations of subsurface tiles using a decision tree classifier which compares the multiple data sets such as enhanced image data, land use class, soil drainage class, hydrologic group and surface slope. Accuracy assessment of the predicted tile map was done by comparing the locations of tile drains with existing historic maps and ground-truth data. The overall performance of decision tree classifier model coupled with other pre- and post- classification methods shows that this model can be a very effective tool in identifying tile lines from aerial photographs over large areas of land. Once the tile map was created, the DHSVM was applied to ACRE and SEPAC respectively to see the hydrological impact of the subsurface drainage network. Observed data for 3-years (1998-2000) at ACRE and for 6-years (1993-1998) at SEPAC were used to calibrate and validate the model. The model was simulated for three scenarios: 1) baseline scenario (no tiles), 2) with known tile lines and 3) with tile lines created through

  2. Subsurface agricultural irrigation drainage: the need for regulation.

    PubMed

    Lemly, A D

    1993-04-01

    Subsurface drainage resulting from irrigated agriculture is a toxic threat to fish and wildlife resources throughout the western United States. Studies by the U.S. Department of the Interior show that migratory waterfowl have been poisoned by drainwater contaminants on at least six national wildlife refuges. Allowing this poisoning to continue is a violation of the Migratory Bird Treaty Act under U.S. Federal law. Critical wetlands and waterfowl populations are threatened in both the Pacific and Central flyways. The public is also at risk and health warnings have been issued in some locations. Subsurface irrigation drainage is a complex effluent containing toxic concentrations of trace elements, salts, and nitrogenous compounds. Some of the contaminants are classified by the U.S. Environmental Protection Agency (EPA) as priority pollutants and they can be present in concentrations that exceed EPA's criteria for toxic waste. The on-farm drainage systems used to collect and transport this wastewater provide point-source identification as well as a mechanism for toxics control through the National Pollutant Discharge Elimination System (NPDES) permit process. A four-step approach is presented for dealing with irrigation drainage in an environmentally sound manner. This regulatory strategy is very similar to those commonly used for industrial discharges and includes site evaluation, contaminant reduction through NPDES, and compliance monitoring. The EPA must recognize subsurface irrigation drainage as a specific class of pollution subject to regulation under the NPDES process. Active involvement by EPA is necessary to ensure that adequate controls on this wastewater are implemented.

  3. Continuous Passive Sampling of Solutes from Agricultural Subsurface Drainage Tubes

    NASA Astrophysics Data System (ADS)

    Lindblad Vendelboe, Anders; de Jonge, Hubert; Rozemeijer, Joachim; Wollesen de Jonge, Lis

    2015-04-01

    Agricultural subsurface tube drain systems play an important role in water and solute transport. One study, focusing on lowland agricultural catchments, showed that subsurface tube drainage contributed up to 80% of the annual discharge and 90% of the annual NO3 load from agricultural fields to the receiving water bodies. Knowledge of e.g. nutrient loads and drainage volumes, based on measurements and modelling, are important for adequate water quality management. Despite the importance of tube drain transport of solutes, monitoring data are scarce. This scarcity is a result of the existing monitoring techniques for flow and contaminant load from tube drains being expensive and labor-extensive. The study presented here aimed at developing a cheap, simple, and robust method to monitor solute loads from tube drains. The method is based on the newly developed Flowcap, which can be attached to existing tube drain outlets and can measure total flow, contaminant load and flow-averaged concentrations of solutes in the drainage. The Flowcap builds on the existing Sorbicell principle, a passive sampling system that measures average concentrations over longer periods of time (days to months) for various compounds. The Sorbicell consists of two compartments permeable to water. One compartment contains an adsorbent and one contains a tracer. When water passes through the Sorbicell the compound of interest is absorbed while a tracer is released. Using the tracer loss to calculate the volume of water that has passed the Sorbicell it is possible to calculate the average concentration of the compound. When mounting Sorbicells in the Flowcap, a flow-proportional part of the drainage is sampled from the main stream. To accommodate the wide range of drainage flow rates two Flowcaps with different capacities were tested in the laboratory: one with a capacity of 25 L min-1 (Q25) and one with a capacity of 256 L min-1 (Q256). In addition, Sorbicells with two different hydraulic

  4. Phosphorus transport in agricultural subsurface drainage: A review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) loss from agricultural fields and watersheds has been an important water quality issue for decades because of the critical role P plays in eutrophication. Historically, most research focused on P losses by surface runoff and erosion because subsurface P losses were often deemed to be ...

  5. Detecting Subsurface Agricultural Tile Drainage using GIS and Remote Sensing Technique

    NASA Astrophysics Data System (ADS)

    Budhathoki, M.; Gokkaya, K.; Tank, J. L.; Christopher, S. F.; Hanrahan, B.

    2015-12-01

    Subsurface tile drainage is a common practice in many of the row crop dominated agricultural lands in the Upper Midwest, which increases yield by making the soil more productive. It is reported that nearly half of all cropland in Indiana benefits from some sort of artificial drainage. However, subsurface tile has a significant negative impact on surface water quality by providing a fast means of transport for nutrients from fertilizers. Therefore, generating spatial data of tile drainage in the field is important and useful for agricultural landscape and hydrological studies. Subsurface tile drains in Indiana's croplands are not widely mapped. In this study, we will delineate subsurface tile drainage in agricultural land in Shatto Ditch watershed, located in Kosciusko County, Indiana. We will use geo-spatial methodology, which was purposed by earlier researchers to detect tile drainage. We will use aerial color-infrared and satellite imagery along with Light Detection and Ranging (LiDAR) data. In order to map tile lines with possible accuracy, we will use GIS-based analysis in combination with remotely sensed data. This research will be comprised of three stages: 1) masking out the potential drainage area using a decision tree rule based on land cover information, soil drainage category, surface slope, and satellite image differencing technique, 2) delineate tile lines using image processing techniques, and 3) check the accuracy of mapped tile lines with ground control points. To our knowledge, this study will be the first to check the accuracy of mapping with ground truth data. Based on the accuracy of results, we will extend the methodology to greater spatial scales. The results are expected to contribute to better characterizing and controlling water pollution sources in Indiana, which is a major environmental problem.

  6. Seasonal Patterns in Microbial Community Composition in Denitrifying Bioreactors Treating Subsurface Agricultural Drainage.

    PubMed

    Porter, Matthew D; Andrus, J Malia; Bartolerio, Nicholas A; Rodriguez, Luis F; Zhang, Yuanhui; Zilles, Julie L; Kent, Angela D

    2015-10-01

    Denitrifying bioreactors, consisting of water flow control structures and a woodchip-filled trench, are a promising approach for removing nitrate from agricultural subsurface or tile drainage systems. To better understand the seasonal dynamics and the ecological drivers of the microbial communities responsible for denitrification in these bioreactors, we employed microbial community "fingerprinting" techniques in a time-series examination of three denitrifying bioreactors over 2 years, looking at bacteria, fungi, and the denitrifier functional group responsible for the final step of complete denitrification. Our analysis revealed that microbial community composition responds to depth and seasonal variation in moisture content and inundation of the bioreactor media, as well as temperature. Using a geostatistical analysis approach, we observed recurring temporal patterns in bacterial and denitrifying bacterial community composition in these bioreactors, consistent with annual cycling. The fungal communities were more stable, having longer temporal autocorrelations, and did not show significant annual cycling. These results suggest a recurring seasonal cycle in the denitrifying bioreactor microbial community, likely due to seasonal variation in moisture content.

  7. Nitrate-nitrogen losses through subsurface drainage under various agricultural land covers.

    PubMed

    Qi, Zhiming; Helmers, Matthew J; Christianson, Reid D; Pederson, Carl H

    2011-01-01

    Nitrate-nitrogen (NO₃-N) loading to surface water bodies from subsurface drainage is an environmental concern in the midwestern United States. The objective of this study was to investigate the effect of various land covers on NO₃-N loss through subsurface drainage. Land-cover treatments included (i) conventional corn ( L.) (C) and soybean [ (L.) Merr.] (S); (ii) winter rye ( L.) cover crop before corn (rC) and before soybean (rS); (iii) kura clover ( M. Bieb.) as a living mulch for corn (kC); and (iv) perennial forage of orchardgrass ( L.) mixed with clovers (PF). In spring, total N uptake by aboveground biomass of rye in rC, rye in rS, kura clover in kC, and grasses in PF were 14.2, 31.8, 87.0, and 46.3 kg N ha, respectively. Effect of land covers on subsurface drainage was not significant. The NO₃-N loss was significantly lower for kC and PF than C and S treatments (p < 0.05); rye cover crop did not reduce NO₃-N loss, but NO₃-N concentration was significantly reduced in rC during March to June and in rS during July to November (p < 0.05). Moreover, the increase of soil NO₃-N from early to late spring in rS was significantly lower than the S treatment (p < 0.05). This study suggests that kC and PF are effective in reducing NO₃-N loss, but these systems could lead to concerns relative to grain yield loss and change in farming practices. Management strategies for kC need further study to achieve reasonable corn yield. The effectiveness of rye cover crop on NO-N loss reduction needs further investigation under conditions of different N rates, wider weather patterns, and fall tillage.

  8. Use of Continuous Specific Conductance to Differentiate the Sources of Water to an Agricultural Stream With Subsurface Drainage Networks

    NASA Astrophysics Data System (ADS)

    Smith, E. A.; Thornburg, J.; Capel, P. D.

    2008-12-01

    The sources of water to natural streams include direct precipitation, overland flow, and ground-water inflow. In glaciated areas, the presence of artificial surface and subsurface drainage networks, a common practice for removing excess water from agricultural fields, provides additional pathways of water movement to the stream. The artificial drainage of agricultural fields allows rainfall to move quickly through the catchment to the stream transporting nutrients, pesticides and other agricultural-related constituents. A largely agricultural (about 90%), 31 km2 subcatchment of the South Fork of the Iowa River in north-central Iowa was studied for two years. Discharge and specific conductance (SC) were measured continuously and discreet water samples were obtained for analyses of nutrients and other constituents. SC is an electrical measurement of the total ion content in the water. The SC of the rain and ground-water is about 10 microS/cm and 800-1,200 microS/cm, respectively. The typical, base-flow SC of the stream is 700-800 microS/cm. Within minutes after a substantial rain event, the stream discharge increases and the SC decreases (often times below 200"nmicroS/cm). The rain water is processed through the catchment before it reaches the stream via direct overland flow, preferential flow to subsurface drains, vertical drains attached to subsurface drains in ponded areas, and/or soil infiltration to ground-water. Water moving through each of these pathways has different characteristic time scales and different degrees of interactions with the soil yielding different ionic content, thus different SC. Both the discharge and SC concurrently return to the typical base-flow values over the following days and weeks. This strong relation between rainfall, discharge and SC is used to calculate the relative importance and time scale of the various hydrologic pathways. In addition to the two-year stream record, complementary discharge and SC data were collected in two

  9. Agricultural Drainage Water Management in the Upper Mississippi River Basin: Potential Impact and Implementation Strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The unique soil and climate of the Upper Mississippi River Basin area provide the resources for bountiful agricultural production. Agricultural drainage (both surface and subsurface drainage) is essential for achieving economically viable crop production and management. Drainage practices alter the ...

  10. Agricultural drainage water management: Potential impact and implementation strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The unique soil and climate of the Upper Mississippi River Basin (and the Lake Erie Basin) area provide the resources for bountiful agricultural production. Agricultural drainage (both surface and subsurface drainage) is essential for achieving economically viable crop production and management. Dra...

  11. Condensed research overview of agricultural drainage pipe detection and assessment using ground penetrating radar

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural subsurface drainage practices are employed in many places throughout the world to remove excess water from soil, thereby improving crop production. In order to improve and evaluate the efficiency of these subsurface drainage systems, non-destructive methods are needed to not only locate...

  12. Agricultural drainage pipe detection using ground penetrating radar: Effects of antenna orientation relative to drainage pipe directional trend

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Locating buried agricultural drainage pipes is a difficult problem confronting farmers and land improvement contractors, especially in the Midwest U.S., where the removal of excess soil water using subsurface drainage systems is a common farm practice. Enhancing the efficiency of soil water removal ...

  13. Agricultural Drainage Water Management: Potential Impact and Implementation Strategies for Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The unique soil and climate of the Upper Mississippi River Basin (and the Lake Erie Basin) area provide the resources for bountiful agricultural production. Agricultural drainage (both surface and subsurface drainage) is essential for achieving economically viable crop production and management. Dra...

  14. AGRICULTURAL DRAINAGE WELLS: IMPACT ON GROUND WATER

    EPA Science Inventory

    This document discusses agricultural drainage well practices, potential contamination problems that may occur, and possible management practices or regulatory solutions that could be used to alleviate those problems. The document has been written for use by state and Agency deci...

  15. Influence of alternative and conventional farming practices on subsurface drainage and water quality.

    PubMed

    Oquist, K A; Strock, J S; Mulla, D J

    2007-01-01

    Agricultural runoff contributes nutrients to nonpoint-source pollution of surface waters. This study was conducted to investigate the potential use of alternative farming practices to improve water quality. The study examined the effects of both alternative and conventional farming practices on subsurface drainage and nitrogen and phosphorus loss through subsurface drainage from glacial till soils (i.e., Calciaquolls, Endoaquolls, Eutrudepts, Hapludolls) in southwest Minnesota. Alternative farming practices included organic management practices, species biodiversity, and/or practices that include reduced inputs of synthetic fertilizer and pesticides. Conventional farming practices include corn-soybean (Zea mays L.-Glycine max L., respectively) rotations and their associated recommended fertilizer rates as well as pesticide usage. Precipitation was highly variable during the 3-yr study period including a below-average year (2003), an average year (2002), and an above-average year (2004). Results indicate that alternative farming practices reduced subsurface drainage discharge by 41% compared with conventional practices. Flow-weighted mean nitrate-nitrogen (nitrate N) concentrations during tile flow were 8.2 and 17.2 mg L(-1) under alternative and conventional farming practices, respectively. Alternative farming practices reduced nitrate N losses by between 59 and 62% in 2002 and 2004 compared with conventional practices. Ammonium-nitrogen (ammonium N), orthophosphorus, and total phosphorus losses in subsurface drainage were very low and did not pose a substantial risk of pollution. Results suggest that alternative farming practices have the potential to reduce agricultural impacts on water quality.

  16. Minimizing contamination hazards to waterbirds using agricultural drainage evaporation ponds

    NASA Astrophysics Data System (ADS)

    Bradford, David F.; Smith, Lynda A.; Drezner, Deborah S.; Shoemaker, J. David

    1991-11-01

    In much of the San Joaquin Valley, California, USA, inadequate drainage of applied irrigation water and accumulating salts in the soil have necessitated the installation of subsurface tile drainage systems to preserve crop productivity. At present, these subsurface drainage waters are disposed of by means of evaporation ponds or discharges into the San Joaquin River. Unfortunately, most of these agricultural drainage waters contain high concentrations of salts and naturally occurring trace elements, such as selenium, and recent evidence indicates that substantial numbers of waterbirds are exposed to contamination by selenium in the evaporation ponds. In order to avoid, minimize, or mitigate the adverse impacts on wildlife using the ponds, alternative pond management methods must be identified and evaluated for implementation. A number of methods have the potential to be cost-effective in significantly reducing the contamination hazard to birds using agricultural evaporation ponds. Twenty general methods were evaluated in this study, and four methods are recommended for implementation: remove levee vegetation, remove windbreaks, deepen the ponds, and haze birds. A number of other methods are recommended for further consideration because they appear to have good prospects for reducing the contamination hazard: steepen interior levee slopes, apply herbicides and insecticides, place netting on pond shorelines, and provide freshwater habitat adjacent to evaporation ponds. It may be necessary to use a combination of methods to effectively control selenium contamination of aquatic birds because it is unlikely that a single affordable pond management method will be able to entirely eliminate the contamination hazard.

  17. Climate, Landscape, and Management Effects on Nitrate and Soluble Phosphorus concentrations in subsurface drainage discharge in the western Lake Erie basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface drainage, while an important and necessary agricultural production practice in the Midwest, contributes nitrate (NO3) and soluble phosphorus (P) to surface waters. The magnitude of NO3 and soluble P losses in subsurface drainage varies greatly by landscape, climate, and field management f...

  18. Effects of soil type upon metolachlor losses in subsurface drainage.

    PubMed

    Novak, S M; Portal, J M; Schiavon, M

    2001-01-01

    A field experiment at La Bouzule (Lorraine, France) investigated metolachlor movement to subsurface drains in two soil types, a silt loam and a heavy clay soil, under identical agricultural management practices and climatic conditions. Drainage volumes and concentrations of metolachlor in the soil plough layer and drainwater were monitored after herbicide application from May 1996 to February 1997, and from May to August 1998. Total losses in drainwater were 0.08% and 0.18% of the amount applied to the silt loam compared with 0.59% and 0.41% for the clay soil, in 1996/97 and 1998, respectively. In 1996/97, 32% of total metolachlor loss from the silt loam and 91% from the clay soil occurred during the spring/summer period following treatment. Peak concentrations were 18.5 and 171.6 microg l(-1) for the silt loam and 130.6 and 395.3 microg l(-1) for the clay soil during the spring/summer periods of 1996/97 and 1998, respectively. During the autumn/winter period, concentrations did not exceed 2.2 microg l(-1) for the silt loam and 2.6 microg l(-1) for the clay soil. The experimental results indicate that metolachlor losses in drainwater were primarily caused by preferential flow (macropore flow) which was greater in the clay soil than in the silt loam, and occurring mainly during the spring/summer periods.

  19. Location of Agricultural Drainage Pipes and Assessment of Agricultural Drainage Pipe Conditions Using Ground Penetrating Radar

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methods are needed to not only locate buried agricultural drainage pipe, but to also determine if the pipes are functioning properly with respect to water delivery. The primary focus of this research project was to confirm the ability of ground penetrating radar (GPR) to locate buried drainage pipe ...

  20. Isotopic mixing model for quantifying contributions of soil water and groundwater in subsurface ('tile') drainage

    NASA Astrophysics Data System (ADS)

    Kennedy, C. D.; Gall, H.; Jafvert, C. T.; Bowen, G. J.

    2010-12-01

    Subsurface (‘tile’) drainage, consisting of buried grids of perforated pipe, has provided a means of converting millions of acres of poorly drained soils in the Midwestern U.S. into fertile cropland. However, by altering pathways and rates of soil water and groundwater movement through agricultural lands, this practice may accelerate the loss of nitrate and other agrochemicals. To better understand the hydrological controls on nitrogen dynamics in artificially drained agricultural watersheds, a field sampling program has been established at the Animal Science Research and Education Center (ASREC) at Purdue University (West Lafayette, Indiana) to (1) measure precipitation amount, tile flow, and water-table elevation, and (2) collect water samples for analysis of nitrate, major ions, and oxygen isotope ratios in precipitation, tile drainage, shallow (1 m) and deep (3 m) groundwater, and soil water during storm events. Preliminary physical, chemical, and isotopic data collected at the ASREC show a coincident timing of peak storm ‘event water’ and peak nitrate flux in tile drainage, suggesting significant routing of infiltrating event water. In this work, we aim to refine our understanding of tile drainage at the ASREC by developing a mixing model for partitioning contributions of soil water and groundwater in tile drainage during several storm runoff events ranging in precipitation intensity and coinciding with varying antecedent soil moisture conditions. The results of our model will describe tile drainage in terms of its hydrological components, soil water and groundwater, which in turn will provide a means of incorporating the effects of tile drainage in surface/subsurface hydrological transport models.

  1. Socially optimal drainage system and agricultural biodiversity: a case study for Finnish landscape.

    PubMed

    Saikkonen, Liisa; Herzon, Irina; Ollikainen, Markku; Lankoski, Jussi

    2014-12-15

    This paper examines the socially optimal drainage choice (surface/subsurface) for agricultural crop cultivation in a landscape with different land qualities (fertilities) when private profits and nutrient runoff damages are taken into account. We also study the measurable social costs to increase biodiversity by surface drainage when the locations of the surface-drained areas in a landscape affect the provided biodiversity. We develop a general theoretical model and apply it to empirical data from Finnish agriculture. We find that for low land qualities the measurable social returns are higher to surface drainage than to subsurface drainage, and that the profitability of subsurface drainage increases along with land quality. The measurable social costs to increase biodiversity by surface drainage under low land qualities are negative. For higher land qualities, these costs depend on the land quality and on the biodiversity impacts. Biodiversity conservation plans for agricultural landscapes should focus on supporting surface drainage systems in areas where the measurable social costs to increase biodiversity are negative or lowest.

  2. Laboratory evaluation of zero valent iron and sulfur modified iron filter materials for agricultural drainage water treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    On site filter treatment systems have the potential to remove nutrients and pesticides from agricultural subsurface drainage waters. The effectiveness and efficiency of this type of drainage water treatment will depend on the actual filter materials utilized. Two promising filter materials that coul...

  3. Ecology and management of agricultural drainage ditches: a literature review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage ditches are headwater streams that have been modified or constructed for agricultural drainage, and are often used in conjunction with tile drains. These modified streams are a common landscape feature in Ohio, and constitute 25% of stream habitat within the state. Management o...

  4. PASSIVE TREATMENT OF ACID ROCK DRAINAGE FROM A SUBSURFACE MINE

    EPA Science Inventory

    Acidic, metal-contaminated drainages are a critical problem facing many areas of the world. Acid rock drainage results when metal sulfide minerals, particularly pyrite, are oxidized by exposure to oxygen and water. The deleterious effects of these drainages on receiving streams a...

  5. Preliminary results from agricultural drainage water management CIG projects on Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field demonstrations were monitored to compare the crop yields, drainage discharge, and nutrient loadings to streams from managed and unmanaged subsurface drainage systems. Paired drainage systems within the same field, under similar soil, area, cropping, and management conditions, were identified. ...

  6. Impacts of drainage water management on subsurface drain flow, nitrate concentration, and nitrate loads in Indiana

    EPA Science Inventory

    Drainage water management is a conservation practice that has the potential to reduce drainage outflow and nitrate (NO3) loss from agricultural fields while maintaining or improving crop yields. The goal of this study was to quantify the impact of drainage water management on dra...

  7. Determining potential for microbial atrazine degradation in agricultural drainage ditches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Passage of agricultural runoff through vegetated drainage ditches has been shown to reduce the amount of pesticides, such as atrazine, exiting agricultural watersheds. Previous studies found that microbial communities in soil from fields treated with atrazine display enhanced rates of atrazine degr...

  8. Subsurface drainage volume reduction with drainage water management: Case studies in Ohio, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the main contributors to poor water quality in the Mississippi River and aeral increase in the hypoxic zone in the Gulf of Mexico is intensive drainage of the cropland within the watershed. Controlled drainage has been demonstrated as an approach to curb totla drainage outflow and nutrient di...

  9. An analytical solution for predicting the transient seepage from a subsurface drainage system

    NASA Astrophysics Data System (ADS)

    Xin, Pei; Dan, Han-Cheng; Zhou, Tingzhang; Lu, Chunhui; Kong, Jun; Li, Ling

    2016-05-01

    Subsurface drainage systems have been widely used to deal with soil salinization and waterlogging problems around the world. In this paper, a mathematical model was introduced to quantify the transient behavior of the groundwater table and the seepage from a subsurface drainage system. Based on the assumption of a hydrostatic pressure distribution, the model considered the pore-water flow in both the phreatic and vadose soil zones. An approximate analytical solution for the model was derived to quantify the drainage of soils which were initially water-saturated. The analytical solution was validated against laboratory experiments and a 2-D Richards equation-based model, and found to predict well the transient water seepage from the subsurface drainage system. A saturated flow-based model was also tested and found to over-predict the time required for drainage and the total water seepage by nearly one order of magnitude, in comparison with the experimental results and the present analytical solution. During drainage, a vadose zone with a significant water storage capacity developed above the phreatic surface. A considerable amount of water still remained in the vadose zone at the steady state with the water table situated at the drain bottom. Sensitivity analyses demonstrated that effects of the vadose zone were intensified with an increased thickness of capillary fringe, capillary rise and/or burying depth of drains, in terms of the required drainage time and total water seepage. The analytical solution provides guidance for assessing the capillary effects on the effectiveness and efficiency of subsurface drainage systems for combating soil salinization and waterlogging problems.

  10. Subsurface Drainage of Pavement Structures: Current Corps of Engineers and Industry Practice

    DTIC Science & Technology

    1991-12-01

    few decades. General material on drainage an emphasis on subsurface drainage. The topics dis- issues can be found in the work of Cedergren (1974, cussed...the sides of the United States. bottom of the pavement layers. The assumptions made Cedergren (1974) bases his infiltration estimates on about these...temperature, but also whetheror all water falling on the pavement area will infiltrate. I Alternatively. Cedergren (1974) assumes that bitu- The FHWA

  11. Relative importance of impervious area, drainage density, width function, and subsurface storm drainage on flood runoff from an urbanized catchment

    NASA Astrophysics Data System (ADS)

    Ogden, Fred L.; Raj Pradhan, Nawa; Downer, Charles W.; Zahner, Jon A.

    2011-12-01

    The literature contains contradictory conclusions regarding the relative effects of urbanization on peak flood flows due to increases in impervious area, drainage density and width function, and the addition of subsurface storm drains. We used data from an urbanized catchment, the 14.3 km2 Dead Run watershed near Baltimore, Maryland, USA, and the physics-based gridded surface/subsurface hydrologic analysis (GSSHA) model to examine the relative effect of each of these factors on flood peaks, runoff volumes, and runoff production efficiencies. GSSHA was used because the model explicitly includes the spatial variability of land-surface and hydrodynamic parameters, including subsurface storm drains. Results indicate that increases in drainage density, particularly increases in density from low values, produce significant increases in the flood peaks. For a fixed land-use and rainfall input, the flood magnitude approaches an upper limit regardless of the increase in the channel drainage density. Changes in imperviousness can have a significant effect on flood peaks for both moderately extreme and extreme storms. For an extreme rainfall event with a recurrence interval in excess of 100 years, imperviousness is relatively unimportant in terms of runoff efficiency and volume, but can affect the peak flow depending on rainfall rate. Changes to the width function affect flood peaks much more than runoff efficiency, primarily in the case of lower density drainage networks with less impermeable area. Storm drains increase flood peaks, but are overwhelmed during extreme rainfall events when they have a negligible effect. Runoff in urbanized watersheds with considerable impervious area shows a marked sensitivity to rainfall rate. This sensitivity explains some of the contradictory findings in the literature.

  12. Assessment of Agricultural Drainage Pipe Conditions Using Ground Penetrating Radar

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Farmers and land improvement contractors, especially in the Midwest U.S., need methods to not only locate buried agricultural drainage pipe, but also to determine if the pipes are functioning properly with respect to water delivery. Previous investigations have already demonstrated the feasibility o...

  13. Internal hydraulics of an agricultural drainage denitrification bioreactor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Denitrification bioreactors to reduce the amount of nitrate-nitrogen in agricultural drainage are now being deployed across the U.S. Midwest. However, there are still many unknowns regarding internal hydraulic-driven processes in these "black box" engineered treatment systems. To improve this unders...

  14. Influence of Physical Habitat and Agricultural Contaminants on Fishes within Agricultural Drainage Ditches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage ditches are used within agricultural watersheds for the removal of excess water from agricultural fields. These headwater streams have been constructed or modified so they possess an enlarged trapezoidal cross-section, straightened channels, and riparian zones lacking woody veg...

  15. A GPR agricultural drainage pipe detection case study: Effects of antenna orientation relative to drainage pipe directional trend

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Locating buried drainage pipes is a difficult task confronting farmers and land improvement contractors, especially in the Midwest U.S., where the removal of excess soil water using subsurface drainage systems is a common farm practice. Enhancing the efficiency of soil water removal on land containi...

  16. Simulating the Effects of Drainage and Agriculture on Hydrology and Sediment in the Minnesota River Basin

    NASA Astrophysics Data System (ADS)

    Downer, C. W.; Pradhan, N. R.; Skahill, B. E.; Banitt, A. M.; Eggers, G.; Pickett, R. E.

    2014-12-01

    Throughout the Midwest region of the United States, slopes are relatively flat, soils tend to have low permeability, and local water tables are high. In order to make the region suitable for agriculture, farmers have installed extensive networks of ditches to drain off excess surface water and subsurface tiles to lower the water table and remove excess soil water in the root zone that can stress common row crops, such as corn and soybeans. The combination of tiles, ditches, and intensive agricultural land practices radically alters the landscape and hydrology. Within the watershed, tiles have outlets to both the ditch/stream network as well as overland locations, where the tile discharge appears to initiate gullies and exacerbate overland erosion. As part of the Minnesota River Basin Integrated Study we are explicitly simulating the tile and drainage systems in the watershed at multiple scales using the physics-based watershed model GSSHA (Gridded Surface Subsurface Hydrologic Analysis). The tile drainage system is simulated as a network of pipes that collect water from the local water table. Within the watershed, testing of the methods on smaller basins shows the ability of the model to simulate tile flow, however, application at the larger scale is hampered by the computational burden of simulating the flow in the complex tile drain networks that drain the agricultural fields. Modeling indicates the subsurface drains account for approximately 40% of the stream flow in the Seven Mile Creek sub-basin account in the late spring and early summer when the tile is flowing. Preliminary results indicate that agricultural tile drains increase overland erosion in the Seven Mile Creek watershed.

  17. Nutrient mitigation efficiency in agricultural drainage ditches: An influence of landscape properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drainage systems are integral parts of the agricultural landscapes and have the ability to intercept nutrient loading from runoff to surface water. This study investigated nutrient removal efficiency within replicated experimental conventional and controlled (with weirs) agricultural drainage ditche...

  18. Transport of tylosin and tylosin-resistance genes in subsurface drainage water from manured fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal agriculture appears to contribute to the spread of antibiotic resistance genes, but few studies have quantified gene transport in agricultural fields. The transport of tylosin, tylosin-resistance genes (erm B, F, A) and tylosin-resistant Enterococcus were measured in tile drainage water from ...

  19. Evaluation of revised subsurface tile drainage algorithms in SWAT for a cold climate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface tile drains in agricultural systems of the Mid-west U.S. are a major contributor of nitrate loadings to the Mississippi River Basin and contribute to hypoxic conditions in the northern Gulf of Mexico. Development of strategies to reduce nitrate loadings from these agricultural systems req...

  20. Evaluation on the Efficiency of Subsurface Drainage in Chiu-Fen Landslide at Northern Taiwan

    NASA Astrophysics Data System (ADS)

    Ying, L. Y.; Lin, D. G.

    2015-12-01

    For administrative district, the Chiu-Fen landslide is situated at northern Taiwan and comes within the jurisdiction of Ruei-Fang district, New Taipei City Government. Chiu-Fen village is a famous spot for sightseeing and tourism in Southeast Asia. In the last decade, for economic purpose, a vast area of slope land in Chiu-Fen area was reclaimed into business and commercial districts. However, due to the complicated geological and hydrological conditions, improper reclamation, and lack of appropriate soil and water conservation facilities, large scale landslides are frequently triggered by typhoon rainfall and causes damages to the transportation and residential building in the community. As a consequence, the government initiated a comprehensive field investigations and remediation plans to stabilize the landslide from 1997 and the remediation works were concentrated on subsurface drainages, namely the application of drainage well (a vertical shaft with multi-level horizontal drainage boreholes). To investigate the efficiency of drainage wells on the landslide, the A1-profile in the landslide which covers the drainage wells W2 and W4 was selected for a series of rainfall seepage and slope stability analyses. In addition, a 48-hrs design rainfall with return period of 25, 50 and 100 years based on the local meteorological data bank was adopted for the analyses. The numerical results indicate the factor safety FS of the three potential sliding surfaces within A1-profile are constantly keeping greater than one (FS > 1.0) and without decreasing with the elapsed time during rainfall. This implies that the subsurface drainage works can drain off the infiltrated rainwater from a high intensity and long duration rainfall and preserve the slope stability of landslides from deterioration. Finally, the efficiency of the drainage wells can be evaluated quantitatively in terms of the time-dependent factor of safety and the pore water pressure distribution on several potential

  1. Mitigating nutrient leaching with a sub-surface drainage layer of granulated tires.

    PubMed

    Lisi, R D; Park, J K; Stier, J C

    2004-01-01

    Markets for scrap tires have expanded since the early 1990s with the development of value-added applications such as tire-derived fuel and crumb-rubber-amended asphalt. Granulated tires have also displayed the ability to adsorb volatile organic compounds, indicating that the rubber material can be a useful filter media. Sand-based root zones, typically used for golf course putting green and athletic field construction, lack sufficient cation exchange capacity to restrict nitrogen and phosphorus migration through the root zone and into sub-surface drainage systems. Therefore, the adsorptive properties of tire rubber for retaining nitrogen and phosphorus were studied when applied as a distinct sub-surface drainage or intermediate layer in golf course putting greens. A statistically significant reduction in the concentration of nitrate in leachate was achieved by replacing traditional pea gravel with equally sized granulated tires for the drainage layer media, although the mechanism of nitrate mitigation remains unclear. The results indicate that using granulated tires as a drainage layer or fill material beneath sand-based root zones does not compromise the function of the profile or quality of the vegetation while creating an environmentally beneficial and value-added option for scrap tire reuse.

  2. Laboratory Evaluation of Sulfur Modified Iron for Use as a Filter Material to Treat Agricultural Drainage Waters

    NASA Astrophysics Data System (ADS)

    Allred, B. J.

    2009-12-01

    Where subsurface drainage practices are employed, fertilizer nutrients and pesticides applied on farm fields and municipal locations are commonly intercepted by the buried drainage pipes and then discharged into local streams and lakes, oftentimes producing adverse environmental impacts on these surface water bodies. On-site water filter treatment systems can be employed to prevent the release of agricultural nutrients/pesticides into adjacent waterways. Sulfur modified iron is a relatively unknown industrial product that may have promise for use as a filter material to remove contaminants from subsurface drainage waters. Sulfur modified iron (SMI) is a high surface area iron powder (zero valent iron) that has been altered via chemical reaction with pure sulfur to produce a sulfur/iron surface coating on the iron particles. A laboratory investigation was conducted with contaminant removal batch tests, saturated falling-head hydraulic conductivity tests, and saturated solute transport column experiments to evaluate the feasibility for using SMI to treat subsurface drainage waters. Contaminant removal batch tests showed that three SMI samples were much more effective removing nitrate (> 94% nitrate removed) than three zero valent iron samples (< 10% nitrate removed). Batch test results additionally showed that SMI removed greater that 94% of dissolved phosphate, but was not particularly effective removing the pesticide, atrazine (< 37% atrazine removed). Hydraulic conductivity tests indicated that all three SMI samples that were evaluated had sufficient hydraulic conductivity, much greater than the 1 x 10-3 cm/s standard used for stormwater sand filters. The saturated solute transport tests confirmed that SMI can be effective removing nitrate and phosphate from drainage waters. Analysis of column effluent also showed that the large majority of nitrate removed by SMI was converted to ammonium. Consequently, these laboratory findings support the use of SMI in

  3. Modeling water flow in a tile drainage network in glacial clayey tills in an agricultural catchment

    NASA Astrophysics Data System (ADS)

    De Schepper, G.; Therrien, R.; Refsgaard, J.

    2013-12-01

    Tile drainage is a widespread water management practice applied to poorly drained production fields to increase crop productivity and reduce flooding risks. A challenge associated with water resources management in agricultural catchments is to properly understand and quantify the role of tile drainage for the catchment water balance. Only a few studies have been presented where different numerical modeling approaches were tested to simulate tile drainage at the field or catchment scale. These studies suggest that challenges still remainto represent correctly subsurface drainage networks in numerical models while accounting for their influence on water flow and transport. To investigate the impact of tile drains, a variably-saturated flow model has been applied to the Lillebaek agricultural catchment, Denmark. The Lillebaek catchment covers 5 ha and is underlain by about 30 m of Quaternary deposits that consist of a local sandy aquifer with upper and lower clayey till units. A tile drainage network is located in the upper clay till. Water table elevations are recorded daily in a network of piezometers within the catchment, as well as drainage and stream discharge. The control volume finite element HydroGeoSphere model is used to simulate 3D variably-saturated flow in the catchment, coupled with 1D open-channel flow in tile drains and 2D overland flow. That approach requires that the tile drainage network be represented explicitly in the model with 1D elements. The 3D field-scale hydrogeological model was first generated from a national-scale geological model for Denmark combined with available local borehole data. A reference model was then generated for 3D variably-saturated subsurface flow coupled with 2D overland flow. That reference model also incorporates discrete 1D elements to represent the entire drainage network, with a critical depth boundary condition applied to the outlet of the drainage networks. A series of simulation were performed to test the

  4. Sediment delivery from agricultural land to rivers via subsurface drainage

    NASA Astrophysics Data System (ADS)

    Chapman, A. S.; Foster, I. D. L.; Lees, J. A.; Hodgkinson, R. A.

    2005-10-01

    Diffuse sources of sediment and sediment-associated nutrients are of increasing environmental concern because of their impacts on receiving water courses. The aim of the research reported here was to monitor the outflow from four field (land) drains at two farms in the English Midlands in order to estimate the quantity of sediment delivered to the local rivers and the most likely sources and processes involved. A multiparameter sediment unmixing model was employed, using environmental magnetic, geochemical and radionuclide tracers in order to determine the most likely origin of sediments transported through the drains. Results demonstrated that there was a generally linear relationship between drainflow sediment loss and drainflow volume and that the majority (>70%) of the sediment exported from the drains was derived from topsoil. Macropore flow through heavily cracked soils is supported by the data to be the most likely means of sediment delivery to the drains. In one catchment, drains contributed over 50% of the annual sediment budget. Spatial and temporal variations in the sources of sediment reaching one drain outlet were investigated in detail. A link between soil moisture deficit (SMD) and the frequency of high-intensity rainfall events was used to explain the appearance and persistence of a new sediment source in this drain after October 1998. It is concluded that field drains have the potential to be significant conduits of sediment and agrochemicals in a wide variety of environments in the UK. It is also suggested that this potential may increase if projected climate change leads to more intense rainfall events and increases in SMD across a greater area of the UK.

  5. Effects of macro-pores on water flow in coastal subsurface drainage systems

    NASA Astrophysics Data System (ADS)

    Xin, Pei; Yu, Xiayang; Lu, Chunhui; Li, Ling

    2016-01-01

    Leaching through subsurface drainage systems has been widely adopted to ameliorate saline soils. The application of this method to remove salt from reclaimed lands in the coastal zone, however, may be impacted by macro-pores such as crab burrows, which are commonly distributed in the soils. We developed a three-dimensional model to investigate water flow in subsurface drainage systems affected by macro-pores distributed deterministically and randomly through Monte Carlo simulations. The results showed that, for subsurface drainage systems under the condition of continuous surface ponding, macro-pores increased the hydraulic head in the deep soil, which in turn reduced the hydraulic gradient between the surface and deep soil. As a consequence, water infiltration across the soil surface was inhibited. Since salt transport in the soil is dominated by advection, the flow simulation results indicated that macro-pores decreased the efficiency of salt leaching by one order of magnitude, in terms of both the elapsed time and the amount of water required to remove salt over the designed soil leaching depth (0.6 m). The reduction of the leaching efficiency was even greater in drainage systems with a layered soil stratigraphy. Sensitivity analyses demonstrated that with an increased penetration depth or density of macro-pores, the leaching efficiency decreased further. The revealed impact of macro-pores on water flow represents a significant shortcoming of the salt leaching technique when applied to coastal saline soils. Future designs of soil amelioration schemes in the coastal zone should consider and aim to minimize the bypassing effect caused by macro-pores.

  6. Assessment of Filter Materials for Removal of Contaminants From Agricultural Drainage Waters

    NASA Astrophysics Data System (ADS)

    Allred, B. J.

    2007-12-01

    Fertilizer nutrients and pesticides applied on farm fields, especially in the Midwest U.S., are commonly intercepted by buried agricultural drainage pipes and then discharged into local streams and lakes, oftentimes resulting in an adverse environmental impact on these surface water bodies. Low cost filter materials have the potential to remove nutrient and pesticide contaminants from agricultural drainage waters before these waters are released from the farm site. Batch tests were conducted to find filter materials potentially capable of removing nutrient (nitrate and phosphate) and pesticide (atrazine) contaminants from subsurface drainage waters. For each batch test, stock solution (40 g) and filter material (5 g) were combined in 50 mL Teflon centrifuge tubes and mixed with a rotator for 24 hours. The stock solution contained 50 mg/L nitrate-N, 0.25 mg/L phosphate-P, 0.4 mg/L atrazine, 570 mg/L calcium sulfate, and 140 mg/L potassium chloride. Calcium sulfate and potassium chloride were added so that the stock solution would contain anions and cations normally found in agricultural drainage waters. There were six replicate batch tests for each filter material. At the completion of each test, solution was removed from the centrifuge tube and analyzed for nitrate-N, phosphate-P, and atrazine. A total of 38 filter materials were tested, which were divided into five classes; high carbon content substances, high iron content substances, high aluminum content substances, surfactant modified clay/zeolite, and coal combustion products. Batch test results generally indicate, that with regard to the five classes of filter materials; high carbon content substances adsorbed atrazine very effectively; high iron content substances worked especially well removing almost all of the phosphate present; high aluminum content substances lowered phosphate levels; surfactant modified clay/zeolite substantially reduced both nitrate and atrazine; and coal combustion products

  7. Subsurface Drainage Nitrate and Total Reactive Phosphorus Losses in Bioenergy-Based Prairies and Corn Systems.

    PubMed

    Daigh, Aaron L M; Zhou, Xiaobo; Helmers, Matthew J; Pederson, Carl H; Horton, Robert; Jarchow, Meghann; Liebman, Matt

    2015-09-01

    We compare subsurface-drainage NO-N and total reactive phosphorus (TRP) concentrations and yields of select bioenergy cropping systems and their rotational phases. Cropping systems evaluated were grain-harvested corn-soybean rotations, grain- and stover-harvested continuous corn systems with and without a cover crop, and annually harvested reconstructed prairies with and without the addition of N fertilizer in an Iowa field. Drainage was monitored when soils were unfrozen during 2010 through 2013. The corn-soybean rotations without residue removal and continuous corn with residue removal produced similar mean annual flow-weighted NO-N concentrations, ranging from 6 to 18.5 mg N L during the 4-yr study. In contrast, continuous corn with residue removal and with a cover crop had significantly lower NO-N concentrations of 5.6 mg N L when mean annual flow-weighted values were averaged across the 4 yr. Prairies systems with or without N fertilization produced significantly lower concentrations below <1 mg NO-N L than all the row crop systems throughout the study. Mean annual flow-weighted TRP concentrations and annual yields were generally low, with values <0.04 mg TRP L and <0.14 kg TRP ha, and were not significantly affected by any cropping systems or their rotational phases. Bioenergy-based prairies with or without N fertilization and continuous corn with stover removal and a cover crop have the potential to supply bioenergy feedstocks while minimizing NO-N losses to drainage waters. However, subsurface drainage TRP concentrations and yields in bioenergy systems will need further evaluation in areas prone to higher levels of P losses.

  8. Long-term monitoring of nitrate transport to drainage from three agricultural clayey till fields

    NASA Astrophysics Data System (ADS)

    Ernstsen, V.; Olsen, P.; Rosenbom, A. E.

    2015-08-01

    The application of nitrogen (N) fertilisers to crops grown on tile-drained fields is required to sustain most modern crop production, but it poses a risk to the aquatic environment since tile drains facilitate rapid transport pathways with no significant reduction in nitrate. To maintain the water quality of the aquatic environment and the provision of food from highly efficient agriculture in line with the EU's Water Framework Directive and Nitrates Directive, field-scale knowledge is essential for introducing water management actions on-field or off-field and producing an optimal differentiated N-regulation in future. This study strives to provide such knowledge by evaluating on 11 years of nitrate-N concentration measurements in drainage from three subsurface-drained clayey till fields (1.3-2.3 ha) representing approximately 71 % of the surface sediments in Denmark dominated by clay. The fields differ in their inherent hydrogeological field settings (e.g. soil-type, geology, climate, drainage and groundwater table) and the agricultural management of the fields (e.g. crop type, type of N fertilisers and agricultural practices). The evaluation revealed three types of clayey till fields characterised by: (i) low net precipitation, high concentration of nitrate-N, and short-term low intensity drainage at air temperatures often below 5 °C; (ii) medium net precipitation, medium concentration of nitrate-N, and short-term medium-intensity drainage at air temperatures often above 5 °C; and (iii) high net precipitation, low concentration of nitrate-N and long-term high intensity drainage at air temperatures above 5 °C. For each type, on-field water management actions, such as the selection of crop types and introduction of catch crops, appeared relevant, whereas off-field actions only seemed relevant for the latter two field types given the temperature-dependent reduction potential of nitrate off-field. This initial well-documented field-scale knowledge from fields

  9. Subsurface irrigation of potato crop (Solanum tuberosum ssp. Andigena) in Suka Kollus with different drainage systems

    NASA Astrophysics Data System (ADS)

    Serrano-Coronel, Genaro; Chipana-Rivera, René; Fátima Moreno-Pérez, María; Roldán-Cañas, José

    2016-04-01

    Among the most important hydraulic structures of pre-Hispanic ancestral technology developed in the Andean region, we find the suka kollus, aymara word, called also waru waru, en quechua or raised fields, in English. They are raised platforms surrounded by water canals that irrigate subsurface, but also have the function of draining, to deal with floods because they are surrounding Lake Titicaca. They also have the property of generating a thermoregulatory effect to crops, depending on the configuration of the channels and platforms. Such agro-ecosystems are being abandoned, however, if properly addressed crop management and some drainage canals are replaced by underground drains for increased crop area could be very useful in enabling marginal soils affected by salts and / or excess water. For these reasons, the objective of this study was to evaluate the subsurface irrigation in the potato crop in suka kollus under a system of surface drainage, and mixed drainage (surface and subsurface). The study was conducted in marginal soils of Kallutaca area, located 30 km from the city of La Paz, Bolivia, at a height of 3892 m.a.s.l. The cultivation of the potato (Solanum tuberosum ssp. Andigena) was used. Four treatments were tested with different widths of the platforms: T1 (Control) with drainage through channels; T2 (replacing a channel by a drain); T3 (replacing two channels by two drains); T4 (replacing three channels by three drains). The flow of water into the soil from the water table was predominantly upward, except during periods of high rainfall. In terms of treatments, the flow in T1 was higher, mainly at weeks 8 to 11 after seedling emergence, coinciding with the phenological phases of flowering and at the beginning of the tuber ripening. It was followed by T3, T2 and T4 treatments, respectively. Tuber yield, if one considers that the channels detract arable land, was higher in the T3 treatment,16.4 Mg / ha, followed by T2 treatment, 15.2 Mg / ha, T1

  10. Comparison of Contaminant Transport in Agricultural Drainage Water and Urban Stormwater Runoff.

    PubMed

    Ghane, Ehsan; Ranaivoson, Andry Z; Feyereisen, Gary W; Rosen, Carl J; Moncrief, John F

    2016-01-01

    Transport of nitrogen and phosphorus from agricultural and urban landscapes to surface water bodies can cause adverse environmental impacts. The main objective of this long-term study was to quantify and compare contaminant transport in agricultural drainage water and urban stormwater runoff. We measured flow rate and contaminant concentration in stormwater runoff from Willmar, Minnesota, USA, and in drainage water from subsurface-drained fields with surface inlets, namely, Unfertilized and Fertilized Fields. Commercial fertilizer and turkey litter manure were applied to the Fertilized Field based on agronomic requirements. Results showed that the City Stormwater transported significantly higher loads per unit area of ammonium, total suspended solids (TSS), and total phosphorus (TP) than the Fertilized Field, but nitrate load was significantly lower. Nitrate load transport in drainage water from the Unfertilized Field was 58% of that from the Fertilized Field. Linear regression analysis indicated that a 1% increase in flow depth resulted in a 1.05% increase of TSS load from the City Stormwater, a 1.07% increase in nitrate load from the Fertilized Field, and a 1.11% increase in TP load from the Fertilized Field. This indicates an increase in concentration with a rise in flow depth, revealing that concentration variation was a significant factor influencing the dynamics of load transport. Further regression analysis showed the importance of targeting high flows to reduce contaminant transport. In conclusion, for watersheds similar to this one, management practices should be directed to load reduction of ammonium and TSS from urban areas, and nitrate from cropland while TP should be a target for both.

  11. Comparison of Contaminant Transport in Agricultural Drainage Water and Urban Stormwater Runoff

    PubMed Central

    Ranaivoson, Andry Z.; Feyereisen, Gary W.; Rosen, Carl J.; Moncrief, John F.

    2016-01-01

    Transport of nitrogen and phosphorus from agricultural and urban landscapes to surface water bodies can cause adverse environmental impacts. The main objective of this long-term study was to quantify and compare contaminant transport in agricultural drainage water and urban stormwater runoff. We measured flow rate and contaminant concentration in stormwater runoff from Willmar, Minnesota, USA, and in drainage water from subsurface-drained fields with surface inlets, namely, Unfertilized and Fertilized Fields. Commercial fertilizer and turkey litter manure were applied to the Fertilized Field based on agronomic requirements. Results showed that the City Stormwater transported significantly higher loads per unit area of ammonium, total suspended solids (TSS), and total phosphorus (TP) than the Fertilized Field, but nitrate load was significantly lower. Nitrate load transport in drainage water from the Unfertilized Field was 58% of that from the Fertilized Field. Linear regression analysis indicated that a 1% increase in flow depth resulted in a 1.05% increase of TSS load from the City Stormwater, a 1.07% increase in nitrate load from the Fertilized Field, and a 1.11% increase in TP load from the Fertilized Field. This indicates an increase in concentration with a rise in flow depth, revealing that concentration variation was a significant factor influencing the dynamics of load transport. Further regression analysis showed the importance of targeting high flows to reduce contaminant transport. In conclusion, for watersheds similar to this one, management practices should be directed to load reduction of ammonium and TSS from urban areas, and nitrate from cropland while TP should be a target for both. PMID:27930684

  12. Laboratory Feasibility Evaluation of a New Modified Iron Product for Use as a Filter Material to Treat Agricultural Drainage Waters

    NASA Astrophysics Data System (ADS)

    Allred, B. J.

    2010-12-01

    The removal of excess soil water with a subsurface drainage pipe system is a common agricultural practice employed to improve crop yields, especially in the Midwest U.S. However, fertilizer nutrients (nitrate and phosphate) and pesticides applied on farm fields will frequently leach downwards through the soil profile to be intercepted by the buried drainage pipes and then discharged with drainage water into neighboring streams and lakes, oftentimes producing adverse environmental impacts on local, regional, and national scales. On-site drainage water filter treatment systems can potentially be employed to prevent the release of agricultural nutrients/pesticides into adjacent waterways. A recently developed modified iron product may have promise as a filter material used within this type of drainage water treatment system. Therefore, a laboratory study was initiated to directly evaluate the feasibility of employing this new modified iron product as a filter material to treat drainage waters. Laboratory research included saturated falling-head hydraulic conductivity tests, contaminant (nutrient/pesticide) removal batch tests, and saturated solute transport column experiments. The saturated falling-head hydraulic conductivity tests indicate that the unaltered modified iron product by itself has a high enough hydraulic conductivity (> 1.0 x 10-3 cm/s) to normally allow sufficient water flow rates that are needed to make this material hydraulically practical for use in drainage water filter treatment systems. Modified iron hydraulic conductivity can be improved substantially (> 1 x 10-2 cm/s) by using only the portion of this material that is retained on a 100 mesh sieve (particle size > 0.15 mm). Batch test results carried out with spiked drainage water and either unaltered or 100 mesh sieved modified iron showed nitrate reductions of greater than 30% and 100% removal of the pesticide, atrazine. Saturated solute transport columns tests with spiked drainage water

  13. Subsurface transport of orthophosphate in five agricultural watersheds, USA

    USGS Publications Warehouse

    Domagalski, Joseph L.; Johnson, Henry M.

    2011-01-01

    Concentrations of dissolved orthophosphate (ortho P) in the unsaturated zone, groundwater, tile drains, and groundwater/stream water interfaces were assessed in five agricultural watersheds to determine the potential for subsurface transport. Concentrations of iron oxides were measured in the aquifer material and adsorption of ortho P on oxide surfaces was assessed by geochemical modeling. Attenuation of ortho P in these aquifers was attributed primarily to sorption onto iron oxides, and in one location onto clay minerals. Only one location showed a clear indication of phosphorus transport to a stream from groundwater discharge, although groundwater did contribute to the stream load elsewhere. Subsurface ortho P movement at a site in California resulted in a plume down gradient from orchards, which was attenuated by a 200 m thick riparian zone with natural vegetation. Iron oxides had an effect on phosphorus movement and concentrations at all locations, and groundwater chemistry, especially pH, exerted a major control on the amount of phosphorus adsorbed. Groundwater pH at a site in Maryland was below 5 and that resulted in complete sequestration of phosphorus and no movement toward the stream. Geochemical modeling indicated that as the surfaces approached saturation, groundwater concentrations of ortho P rise rapidly.

  14. Research and Development of Laser-Beam Automatic Grade-Control System on High-Speed Subsurface Drainage Equipment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface drainage methods and materials technologies were modernized more through innovative research and development between 1960 and 1975 than during the previous 100 years. By the mid-1970’s, slow, inefficient trench-installation of heavy rigid draintile materials (clay and concrete) gave way t...

  15. Antibiotic resistance and community analysis of surface and subsurface drainage waters in the South Fork Iowa River watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Midwest is a center for swine production leading to application of swine manure onto lands that have artificial subsurface drainage. Previous reports have indicated elevated levels of antibiotic resistance genes (ARGs) in surface water and groundwater around confined animal feeding operations w...

  16. Effect of replacing surface inlets with blind or gravel inlets on sediment and phosphorus subsurface drainage losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine whether modifying open inlets by burying them in gravel capped with 30 cm of sandy clay loam soil or in ve...

  17. Vertical distribution of phosphorus in agricultural drainage ditch soils.

    PubMed

    Vaughan, Robert E; Needelman, Brian A; Kleinman, Peter J A; Allen, Arthur L

    2007-01-01

    Pedological processes such as gleization and organic matter accumulation may affect the vertical distribution of P within agricultural drainage ditch soils. The objective of this study was to assess the vertical distribution of P as a function of horizonation in ditch soils at the University of Maryland Eastern Shore Research Farm in Princess Anne, Maryland. Twenty-one profiles were sampled from 10 agricultural ditches ranging in length from 225 to 550 m. Horizon samples were analyzed for total P; water-extractable P; Mehlich-3 P; acid ammonium oxalate-extractable P, Fe, and Al (P ox, Fe ox, Al ox); pH; and organic C (n = 126). Total P ranged from 27 to 4882 mg kg(-1), P ox from 4 to 4631 mg kg(-1), Mehlich-3 P from 2 to 401 mg kg(-1), and water-extractable P from 0 to 17 mg kg(-1). Soil-forming processes that result in differences between horizons had a strong relationship with various P fractions and P sorption capacity. Fibric organic horizons at the ditch soil surface had the greatest mean P ox, Fe ox, and Al ox concentrations of any horizon class. Gleyed A horizons had a mean Fe ox concentrations 2.6 times lower than dark A horizons and were significantly lower in total P and P ox. Variation in P due to organic matter accumulation and gleization provide critical insight into short- and long-term dynamics of P in ditch soils and should be accounted for when applying ditch management practices.

  18. Adaptation Options for Land Drainage Systems Towards Sustainable Agriculture and Environment: A Czech Perspective

    NASA Astrophysics Data System (ADS)

    Kulhavý, Zbyněk; Fučík, Petr

    2015-04-01

    In this paper, issues of agricultural drainage systems are introduced and discussed from the views of their former, current and future roles and functioning in the Czech Republic (CR). A methodologically disparate survey was done on thirty-nine model localities in CR with different intensity and state of land drainage systems, aimed at description of commonly occurred problems and possible adaptations of agricultural drainage as perceived by farmers, land owners, landscape managers or by protective water management. The survey was focused on technical state of drainage, fragmentation of land ownership within drained areas as well as on possible conflicts between agricultural and environmental interests in a landscape. Achieved results confirmed that there is obviously an increasing need to reassess some functions of prevailingly single-purpose agricultural drainage systems. Drainage intensity and detected unfavourable technical state of drainage systems as well as the risks connected with the anticipated climate change from the view of possible water scarcity claims for a complex solution. An array of adaptation options for agricultural drainage systems is presented, aiming at enhancement of water retention time and improvement of water quality. It encompasses additional flow-controlling measures on tiles or ditches, or facilities for making selected parts of a drainage system inoperable in order to retain or slow down the drainage runoff, to establish water accumulation zones and to enhance water self-cleaning processes. However, it was revealed that the question of landowner parcels fragmentation on drained land in CR would dramatically complicate design and realization of these measures. Presented solutions and findings are propounded with a respect to contemporary and future state policies and international strategies for sustainable agriculture, water management and environment.

  19. Impact of dredging on dissolved phosphorus transport in agricultural drainage ditches of the Atlantic Coastal Plain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drainage ditches can be a key conduit of phosphorus (P) between agricultural soils of the Atlantic coastal plain and local surface waters, including the Chesapeake Bay. This study sought to quantify the effect of a common ditch management practice, sediment dredging, on fate of P in drainage ditches...

  20. Redox Chemistry and Transformation of Arsenic and Selenium in Agricultural Drainage Disposal Ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evaporation ponds are being used for disposal of agricultural drainage waters in the San Joaquin Valley (SJV) of California since there is no option for disposal outside of the valley. The drainage water contains elevated levels of salts and trace elements including arsenic (As) and selenium (Se). T...

  1. Fragipan controls on nitrogen loss by surface and subsurface flow pathways in an upland agricultural watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improved understanding of nutrient transport by surface and subsurface flow pathways is critical to protecting water quality in agricultural watersheds. We sought to compare nitrogen loss in overland and subsurface flow on two opposing hillslopes (north versus south facing), each with contrasting so...

  2. Phosphorus transport by surface and subsurface flow pathways in an upland agricultural watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improved understanding of phosphorus transport by surface and subsurface flow pathways is critical to protecting water quality in agricultural watersheds. While considerable attention has been devoted to understanding phosphorus losses in overland flow, comparatively limited research has examined ph...

  3. Development, testing and application of DrainFlow: A fully distributed integrated surface-subsurface flow model for drainage study

    NASA Astrophysics Data System (ADS)

    Shokri, Ali; Bardsley, William Earl

    2016-06-01

    Hydrological and hydrogeological investigation of drained land is a complex and integrated procedure. The scale of drainage studies may vary from a high-resolution small scale project through to comprehensive catchment or regional scale investigations. This wide range of scales and integrated system behaviour poses a significant challenge for the development of suitable drainage models. Toward meeting these requirements, a fully distributed coupled surface-subsurface flow model titled DrainFlow has been developed and is described. DrainFlow includes both the diffusive wave equation for surface flow components (overland flow, open drain, tile drain) and Richard's equation for saturated/unsaturated zones. To overcome the non-linearity problem created from switching between wet and dry boundaries, a smooth transitioning technique is introduced to buffer the model at tile drains and at interfaces between surface and subsurface flow boundaries. This gives a continuous transition between Dirichlet and Neumann boundary conditions. DrainFlow is tested against five well-known integrated surface-subsurface flow benchmarks. DrainFlow as applied to some synthetic drainage study examples is quite flexible for changing all or part of the model dimensions as required by problem complexity, problem scale, and data availability. This flexibility enables DrainFlow to be modified to allow for changes in both scale and boundary conditions, as often encountered in real-world drainage studies. Compared to existing drainage models, DrainFlow has the advantage of estimating actual infiltration directly from the partial differential form of Richard's equation rather than through analytical or empirical infiltration approaches like the Green and Ampt equation.

  4. Occurrence of atrazine and degradates as contaminants of subsurface drainage and shallow groundwater

    SciTech Connect

    Jayachandran, K.; Steinheimer, T.R.; Moorman, T.B.

    1994-03-01

    Atrazine is a commonly used herbicide in corn (Zea mays L.) growing areas of the USA. Because of its heavy usage, moderate persistence, and mobility in soil, monitoring of atrazine movement under field conditions is essential to assess its potential to contaminate groundwater. Concentrations of atrazine, deisopropylatrazine (DIA), and deethlatraaine (DEA) were measured in subsurface drainage and shallow groundwater beneath continuous, no-till corn. Water samples were collected from the subsurface drain (tile) outlets and suction lysimeters in the growing seasons of 1990 and 1991, and analyzed for atrazine and two principle degradates won solid-phase extraction and HPLC. In 1990, atrazine concentration ranged from 1.3 to 5.1{mu}g L{sup -1} in tile-drain water and from 0.5 to 20.5 {mu}g L{sup -1} in lysimeter water. In general, concentrations of parent and degradates in solution were atrazine > DEA > DIA. Lesser levels of atrazine were measured in 1991 from Plots 2 and 4; however, greater concentrations of atrazine (6.0-8.4 {mu}g L{sup -1}) were measured from plot 5. Throughout the two growing seasons, atrazine concentration in Plot 5 tile-drain water was greater than that of Plots 2 and 4, suggesting a preferential movement of atrazine. Concentrations of DIA and DEA ranged from 0.1 to 2.2 and 0.9 to 3.2 {mu}g L{sup -1} respectively, indicating that the degradation products by themselves or in combination with parent atrazine can exceed the maximum contaminant level (mcl) of 3 {mu}g L{sup -1} even though atrazine by itself may be <3 {mu}g L{sup -1}. The deethylatrazine-to-atrazine ratio (DAR) is an indicator of residence time in soil during transport of atrazine to groundwater. In Plots 2 and 4, DAR values for tile-drain water ranged from 0.43 to 2.70 and 0.50 to 2.66 respectively. By comparison, a DAR of 0.38 to 0.60 was observed in Plot 5, suggesting less residence time in the soil. 38 refs., 5 figs., 4 tabs.

  5. Long-term monitoring of nitrate-N transport to drainage from three agricultural clayey till fields

    NASA Astrophysics Data System (ADS)

    Ernstsen, V.; Olsen, P.; Rosenbom, A. E.

    2015-01-01

    The application of nitrogen (N) fertilisers to crops grown on tile-drained fields is necessary to sustain most modern crop production, but poses a risk to the aquatic environment since tile drains facilitate rapid transport pathways with no significant reduction in nitrate. To maintain the water quality of the aquatic environment and the provision of food from highly efficient agriculture in line with the EU's Water Framework Directive and Nitrates Directive, field-scale knowledge is imperative if there is to be differentiated N-regulation in future. This study describes nitrate-N leaching to drainage based on coherent monitoring of nitrate-N concentrations, the climate, the groundwater table and crop-specific parameters obtained over eleven years (2001-2011) at three subsurface-drained clayey till fields (1.3-2.3 ha). The monitoring results showed significant field differences in nitrate-N transport to drainage. Not only were these caused by periods of bare soil after short-season crops and N-fixing crops (pea), which have been shown to generate high nitrate-N concentrations in drainage, but by the hydrogeological field conditions that were shown to be the controlling factor of nitrate-N transport to drainage. The fields had the following characteristics: (A) the lowest mass transport (13 kg N ha-1) and fertiliser input had short-term and low-intensity drainage with the highest nitrate-N concentrations detected, representing 40% of net precipitation (226 mm) combined with low air temperatures, (B) the medium mass transport (14 kg N ha-1) had medium-term and medium-intensity drainage, representing 42% of net precipitation (471 mm) combined with periods of both low and higher air temperatures, (C) the highest mass transport (19 kg N ha-1) had long-term drainage, representing 68% of net precipitation (617 mm), but had the highest potential for in-situ soil denitrification and post-treatment (e.g. constructed wetlands) due to long periods with both high water

  6. Assessment of In-Stream Phosphorus Dynamics in Agricultural Drainage Ditches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The intensive row crop agricultural systems in the Midwestern United States can enrich surface waters with nutrients. This project was conducted to evaluate the in-stream processing of P in agricultural ditches. Phosphorus injection studies were conducted at seven sites along three drainage ditches ...

  7. Investigation of denitrifying microbe communities within an agricultural drainage system fitted with low-grade weirs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enhancing wetland characteristics in agricultural drainage ditches with the use of low-grade weirs, has been identified as a potential best management practice (BMP) to mitigate nutrient runoff from agriculture landscapes. This study examined microbe community abundance and diversity involved in den...

  8. Analyzing subsurface drain network performance in an agricultural monitoring site with a three-dimensional hydrological model

    NASA Astrophysics Data System (ADS)

    Nousiainen, Riikka; Warsta, Lassi; Turunen, Mika; Huitu, Hanna; Koivusalo, Harri; Pesonen, Liisa

    2015-10-01

    Effectiveness of a subsurface drainage system decreases with time, leading to a need to restore the drainage efficiency by installing new drain pipes in problem areas. The drainage performance of the resulting system varies spatially and complicates runoff and nutrient load generation within the fields. We presented a method to estimate the drainage performance of a heterogeneous subsurface drainage system by simulating the area with the three-dimensional hydrological FLUSH model. A GIS analysis was used to delineate the surface runoff contributing area in the field. We applied the method to reproduce the water balance and to investigate the effectiveness of a subsurface drainage network of a clayey field located in southern Finland. The subsurface drainage system was originally installed in the area in 1971 and the drainage efficiency was improved in 1995 and 2005 by installing new drains. FLUSH was calibrated against total runoff and drain discharge data from 2010 to 2011 and validated against total runoff in 2012. The model supported quantification of runoff fractions via the three installed drainage networks. Model realisations were produced to investigate the extent of the runoff contributing areas and the effect of the drainage parameters on subsurface drain discharge. The analysis showed that better model performance was achieved when the efficiency of the oldest drainage network (installed in 1971) was decreased. Our analysis method can reveal the drainage system performance but not the reason for the deterioration of the drainage performance. Tillage layer runoff from the field was originally computed by subtracting drain discharge from the total runoff. The drains installed in 1995 bypass the measurement system, which renders the tillage layer runoff calculation procedure invalid after 1995. Therefore, this article suggests use of a local correction coefficient based on the simulations for further research utilizing data from the study area.

  9. Assessment of in-stream phosphorus dynamics in agricultural drainage ditches.

    PubMed

    Smith, D R

    2009-06-01

    The intensive agricultural systems in the Midwestern United States can enrich surface waters with nutrients. Agricultural drainage ditches serve as the first and second order streams throughout much of this region, as well as other highly productive agricultural areas in humid regions throughout the world. This project was conducted to evaluate in-stream processing of soluble P (SP) in agricultural drainage ditches. Soluble P injection studies were conducted at seven sites along three drainage ditches (298 to 4300 ha drainage area), and one site on a third-order stream that receives the discharge from the agricultural ditches (19,000 ha drainage area) by increasing the SP concentration in the ditch water by approximately 0.25 mg L(-1). Sediments collected from smaller watersheds contained greater amounts of Mehlich 3 and exchangeable P (ExP), silt and clay size particles, and organic matter. Phosphorus uptake lengths (S(net)) ranged from 40 to 1900 m, and SP uptake rates (U) ranged from 0.4 to 52 mg m(-2) h(-1). Phosphorus S(net) was correlated with ditch geomorphological (i.e. width) and sediment properties (i.e. organic matter, ExP, and equilibrium P concentration; r(2)=1.00, P<0.001), indirect drainage in the watershed (r(2)=0.92, P<0.001), and the amount of small grains, forest, urban area, alfalfa and corn (r(2)=1.00, P<0.0001). Agricultural drainage ditches actively process nutrients and could potentially be managed to optimize this processing to minimize SP export from these landscapes.

  10. The potential of wetlands for mitigating adverse effects of agricultural drainage

    SciTech Connect

    Silverman, G.S.

    1995-12-01

    Agricultural runoff has been clearly identified as a major contributor to the failure of much of the surface water in the United States to meet designated use objectives. Control of agricultural drainage is very problematic. The agriculture industry strongly resists mandated controls, and warns of potential catastrophic consequences in food shortages should production methods be altered. Yet concern grows over the long and short term impact of a variety of contaminants - particularly sediments, nutrients, and pesticides - released to our waters as part of normal agricultural practices. For quite some time, wetlands have been explored for their potential in treating sewage (from both municipal and private systems) and acid mine drainage. Much less work has been done looking at the potential for wetlands to treat agricultural drainage. yet, wetlands may offer tremendous potential for mitigating problems of agricultural runoff while offering farmers desirable (or at least acceptable) uses of marginal land. This paper has two objectives. First, the opportunities for wetlands to be used as agricultural drainage treatment facilities are described. Processes are identified which trap or degrade pollutants, with particular attention given to long-term environmental fate. Second, an experimental wetlands system recently developed in Northwest Ohio is used as an example of system implementation. Emphasis will be given to how the system was developed to optimize pollutant removal within the physical constraints of the site. Preliminary performance data with respect to water quality changes will also be presented.

  11. Estimation of agricultural pesticide use in drainage basins using land cover maps and county pesticide data

    USGS Publications Warehouse

    Nakagaki, Naomi; Wolock, David M.

    2005-01-01

    A geographic information system (GIS) was used to estimate agricultural pesticide use in the drainage basins of streams that are studied as part of the U.S. Geological Survey?s National Water-Quality Assessment (NAWQA) Program. Drainage basin pesticide use estimates were computed by intersecting digital maps of drainage basin boundaries with an enhanced version of the National Land Cover Data 1992 combined with estimates of 1992 agricultural pesticide use in each United States county. This report presents the methods used to quantify agricultural pesticide use in drainage basins using a GIS and includes the estimates of atrazine use applied to row crops, small-grain crops, and fallow lands in 150 watersheds in the conterminous United States. Basin atrazine use estimates are presented to compare and analyze the results that were derived from 30-meter and 1-kilometer resolution land cover and county pesticide use data, and drainage basin boundaries at various grid cell resolutions. Comparisons of the basin atrazine use estimates derived from watershed boundaries, county pesticide use, and land cover data sets at different resolutions, indicated that overall differences were minor. The largest potential for differences in basin pesticide use estimates between those derived from the 30-meter and 1-kilometer resolution enhanced National Land Cover Data 1992 exists wherever there are abrupt agricultural land cover changes along the basin divide. Despite the limitations of the drainage basin pesticide use data described in this report, the basin estimates provide consistent and comparable indicators of agricultural pesticide application in surface-water drainage basins studied in the NAWQA Program.

  12. Influence of instream habitat and water chemistry on amphibians within channelized agricultural headwater streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The widespread use of stream channelization and subsurface tile drainage for draining agricultural fields has led to the development of numerous channelized agricultural headwater streams within agricultural watersheds of the Midwestern United States, Canada, and Europe. Channelized agricultural he...

  13. Conservation implications of amphibian habitat relationships within channelized agricultural headwater streams in the midwestern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The widespread use of stream channelization and subsurface tile drainage for removing water from agricultural fields has led to the development of numerous channelized agricultural headwater streams within agricultural watersheds of the Midwestern United States. Channelized agricultural headwater s...

  14. Constructed wetland attenuation of nitrogen exported in subsurface drainage from irrigated and rain-fed dairy pastures.

    PubMed

    Tanner, C C; Nguyen, M L; Sukias, J P S

    2005-01-01

    Nitrogen removal performance is reported for constructed wetlands treating subsurface drainage from irrigated and rain-fed dairy pastures in North Island, New Zealand. Flow-proportional sampling of inflow and outflow concentrations were combined with continuous flow records to calculate mass balances for the wetlands. Drainage flows from the irrigated catchment were 2.5-4 fold higher and N exports up to 5 fold higher per unit area than for the rain-fed catchment. Hydraulic and associated N loadings to the wetlands were highly pulsed, associated with rainfall, soil water status, and irrigation events. Transient pulses of organic nitrogen were an important form of N loss from the rain-fed landscape in the first year, and were very effectively removed in the wetland (> 90%). Median nitrate concentrations of approximately 10 g m(-3) in the drainage inflows were reduced by 15-67% during passage through the wetlands and annual nitrate-N loads by 16-61% (38-31 7 g N m(-2)y(-1)). Generation in the wetlands of net ammoniacal-N and organic-N (irrigated site) partially negated reduction in nitrate-N loads. The results show that constructed wetlands comprising 1-2% of catchment area can provide moderate reductions in TN export via pastoral drainage, but performance is markedly influenced by variations in seasonal loading and establishment/maturation factors.

  15. Decreasing nitrate-N loads to coastal ecosystems with innovative drainage management strategies in agricultural landscapes: An experimental approach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Controlled drainage in agricultural ditches contributes to a drainage management strategy with potential environmental and production benefits. Innovative drainage strategies including spatially orientated low-grade weirs show promise to significantly improve nutrient (e.g. nitrate-N) reductions by...

  16. Variability of Near-stream, Sub-surface Major-ion and Tracer Concentrations in an Acid Mine Drainage Environment

    NASA Astrophysics Data System (ADS)

    Bencala, K. E.; Kimball, B. A.; Runkel, R. L.

    2006-12-01

    In acid mine drainage environments, tracer-injection and synoptic sampling approaches provide tools for making operational estimates of solute loading within a stream segment. Identifying sub-surface contaminant sources remains a challenge both for characterization of in-stream metal loading and hydrological process research. There is a need to quantitatively define the character and source of contaminants entering streams from ground-water pathways, as well as the potential for changes in water chemistry and contaminant concentrations along these flow paths crossing the sediment-water interface. Complicating the identification of inflows is the mixing of solute sources which may occur in the `near-stream' subsurface areas and specifically along hyporheic exchange flows (HEFs). In Mineral Creek (Silverton, Colorado), major-ion (SO42-, Cl-, Na+, Ca2+, Mg2+) meter-scale sampling shows that subsurface inflows and likely HEFs occur in a hydro- geochemical setting of significant, one order-of-magnitude, spatial variation in the solute concentrations. Transient Storage Models (TSMs) are a tool for interpreting the in-stream responses of solute transport in streams influenced by hyporheic exchange flows. Simulations using the USGS TSM code OTIS are interpreted as suggesting that in Mineral Creek the strong concentration `tailing' of bromide following the tracer injection occurred, at least in part, from HEFs in a hydro - solute transport setting of likely multiple, dispersed and mixed sources of water along a 64 m sub-reach of the nominally gaining stream. In acid mine drainage environments, the ability to distinguish between local and deep solute sources is critical in modeling reactive transport along the stream, as well as in identifying the geochemical evolution of dispersed, subsurface inflows thorough the catchment.

  17. Projected climate change effects on subsurface drainage and the performance of controlled drainage in the Western Lake Erie Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The US Midwest is expected to experience higher intensity rainfall events along with an increased chance of drought during the mid- and late-21st century under climate change. Development of strategies to mitigate the impact of these projected changes on agricultural production may be critical for e...

  18. Contrasting nutrient mitigation and denitrification potential of agricultural drainage environments with different emergent aquatic macrophytes.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Remediation of excess nitrogen (N) in agricultural runoff can be enhanced by establishing wetland vegetation but the role of denitrification in N removal is not well understood in drainage ditches. We quantified differences in N retention during experimental runoff events followed by stagnant period...

  19. Comparison of contaminant transport in agricultural drainage water and urban stormwater runoff

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transport of nitrogen and phosphorus from agricultural and urban landscapes to surface water bodies can cause adverse environmental impacts including hypoxia and harmful algal blooms. The main objective of this long-term study was to quantify and compare contaminant transport from a subsurface-drain...

  20. Hormones, sterols, and fecal indicator bacteria in groundwater, soil, and subsurface drainage following a high single application of municipal biosolids to a field.

    PubMed

    Gottschall, N; Topp, E; Edwards, M; Payne, M; Kleywegt, S; Russell, P; Lapen, D R

    2013-04-01

    A land application of dewatered municipal biosolids (DMB) was conducted on an agricultural field in fall 2008 at a rate of 22Mg dry weight (dw) ha(-1). Pre- and post- application, hormone, sterol and fecal indicator bacteria concentrations were measured in tile drainage water, groundwater (2, 4, 6m depth), surface soil cores, and DMB aggregates incorporated in the soil (∼0.2m depth) for a period of roughly 1year post-application. Hormones and sterols were detected up to 1year post-application in soil and in DMB aggregates. Hormone (androsterone, desogestrel, estrone) contamination was detected briefly in tile water samples (22d and ∼2months post-app), at lowngL(-1) concentrations (2-34ngL(-1)). Hormones were not detected in groundwater. Sterols were detected in tile water throughout the study period post-application, and multiple fecal sterol ratios suggested biosolids as the source. Coprostanol concentrations in tile water peaked at >1000ngL(-1) (22d post-app) and were still >100ngL(-1) at 6months post-application. Fecal indicator bacteria were detected throughout the study period in tile water, groundwater (⩽2m depth), soil and DMB aggregate samples. These bacteria were strongly linearly related to coprostanol in tile water (R(2)>0.92, p<0.05). The limited transport of hormones and sterols to tile drainage networks may be attributed to a combination of the hydrophobicity of these compounds and limited macroporosity of the field soil. This transitory contamination from hormones and sterols is unlikely to result in any significant pulse exposure risk in subsurface drainage and groundwater.

  1. Field experiments of Controlled Drainage of agricultural clay soils show positive effects on water quantity (retention, runoff) and water quality (nitrate leaching).

    NASA Astrophysics Data System (ADS)

    schipper, peter; stuyt, lodewijk; straat, van der, andre; schans, van der, martin

    2014-05-01

    Despite best management practices, agriculture is still facing major challenges to reduce nutrients leaching to the aquatic environment. In deltas, most of total nutrient losses from artificially drained agricultural soils are discharged via drains. Controlled drainage is a promising measure to prevent drainage of valuable nutrients, improve water quality and agricultural yield and adapt to climate change (reduce peak runoff, manage water scarcity and drought). In The Netherlands, this technique has attracted much attention by water managers and farmers alike, yet field studies to determine the expected (positive) effects for Dutch conditions were scarce. Recently, a field experiment was set up on clay soils. Research questions were: how does controlled, subsurface drainage perform on clay soils? Will deeper tile drains function just as well? What are the effects on drain water quality (especially with respect to nitrogen and salt) and crop yield? An agricultural field on clay soils was used to test different tile drainage configurations. Four types of tile drainage systems were installed, all in duplicate: eight plots in total. Each plot has its own outlet to a control box, where equipment was installed to control drain discharge and to measure the flow, concentrations of macro-ions, pH, nitrogen, N-isotopes and heavy metals. In each plot, groundwater observation wells and suction cups are installed in the saturated and vadose zones, at different depths, and crop yield is determined. Four plots discharge into a hydrologic isolated ditch, enabling the determination of water- and nutrient balances. Automatic drain water samplers and innovative nitrate sensors were installed in four plots. These enable identification and unravelling so-called first flush effects (changes in concentrations after a storm event). Water-, chloride- and nitrogen balances have been set up, and the interaction between groundwater and surface water has been quantified. The hydrological

  2. Managing selenium-contaminated agricultural drainage water by the integrated on-farm drainage management system: role of selenium volatilization.

    PubMed

    Lin, Z Q; Cervinka, V; Pickering, I J; Zayed, A; Terry, N

    2002-07-01

    The Integrated on-Farm Drainage Management (IFDM) system was designed to dispose of selenium (Se)-contaminated agricultural irrigation drainage water through the sequential reuse of saline drainage water to grow crops having different salt tolerance. This study quantified the extent of biological volatilization in Se removal from the IFDM system located in the western San Joaquin Valley, California. Selenium volatilization from selected treatment areas, including pickleweed (Salicornia bigelovii Torr.), saltgrass (Distichlis spicata L.), bare soil, and the solar evaporator, was monitored biweekly using an open-flow sampling chamber system during the pickleweed growing season from February to September 1997, and monthly from September 1997 to January 1998. Biological volatilization from the pickleweed section removed 62.0 +/- 3.6 mg Se m(-2) y(-1) to the atmosphere, which was 5.5-fold greater than the Se accumulated in pickleweed tissues (i.e., phytoextraction). The total Se removed by volatilization from the bare soil, saltgrass, and the solar evaporator was 16.7 +/- 1.1, 4.8 +/- 0.3, and 4.3 +/- 0.9mg Se m(-2) y(-1), respectively. Selenium removal by volatilization accounted for 6.5% of the annual total Se input (957.7mg Sem(-2) y(-1)) in the pickleweed field, and about 1% of the total Se input (432.7 mg Se m(-2) y(-1)) in the solar evaporator. We concluded that Se volatilization under naturally occurring field conditions represented a relatively minor, but environmentally important pathway of Se removal from the IFDM system.

  3. Removal of selenium from contaminated agricultural drainage water by nanofiltration membranes

    USGS Publications Warehouse

    Kharaka, Y.K.; Ambats, G.; Presser, T.S.; Davis, R.A.

    1996-01-01

    Seleniferous agricultural drainage wastewater has become a new major source of pollution in the world. In the USA, large areas of farmland in 17 western states, generate contaminated salinized drainage with Se concentrations much higher than 5 ??g/l, the US Environmental Protection Agency water-quality criterion for the protection of aquatic life; Se values locally reach 4200 ??g/l in western San Joaquin Valley, California. Wetland habitats receiving this drainage have generally shown Se toxicosis in aquatic birds causing high rates of embryonic deformity and mortality, or have indicated potential ecological damage. Results of our laboratory flow experiments indicate that nanofiltration, the latest membrane separation technology, can selectively remove > 95% of Se and other multivalent anions from > 90% of highly contaminated water from the San Joaquin Valley, California. Such membranes yield greater water output and require lower pressures and less pretreatment, and therefore, are more cost effective than traditional reverse osmosis membranes. Nanofiltration membranes offer a potential breakthrough for the management of Se contaminated wastes not only from agricultural drainage, but from other sources also.

  4. Subsidence Rates of Drained Agricultural Peatlands in New Zealand and the Relationship with Time since Drainage.

    PubMed

    Pronger, Jack; Schipper, Louis A; Hill, Reece B; Campbell, David I; McLeod, Malcolm

    2014-07-01

    The drainage and conversion of peatlands to productive agro-ecosystems leads to ongoing surface subsidence because of densification (shrinkage and consolidation) and oxidation of the peat substrate. Knowing the ra0te of this surface subsidence is important for future land-use planning, carbon accounting, and economic analysis of drainage and pumping costs. We measured subsidence rates over the past decade at 119 sites across three large, agriculturally managed peatlands in the Waikato region, New Zealand. The average contemporary (2000s-2012) subsidence rate for Waikato peatlands was 19 ± 2 mm yr (± SE) and was significantly less ( = 0.01) than the historic rate of 26 ± 1 mm yr between the 1920s and 2000s. A reduction in the rate of subsidence through time was attributed to the transition from rapid initial consolidation and shrinkage to slower, long-term, ongoing oxidation. These subsidence rates agree well with a literature synthesis of temperate zone subsidence rates reported for similar lengths of time since drainage. A strong nonlinear relationship was found between temperate zone subsidence rates and time since initial peatland drainage: Subsidence (mm yr) = 226 × (years since drained) ( = 0.88). This relationship suggests that time since drainage exerts strong control over the rate of peatland subsidence and that ongoing peatland subsidence rates can be predicted to gradually decline with time in the absence of major land disturbance.

  5. A Physically-based Model for Surface and Subsurface Drainage from Porous Pavement Overlays

    NASA Astrophysics Data System (ADS)

    Eck, B. J.; Barrett, M.; Charbeneau, R. J.

    2010-12-01

    A thin layer of porous asphalt is commonly overlain on regular impermeable pavement to reduce splash and spray and improve visibility in wet weather. The porous layer often has a large hydraulic conductivity (>1cm/s) to encourage infiltration and drainage and therefore contains runoff when the rainfall intensity is low. However, under high rainfall intensity, the layer’s capacity is exceeded and drainage occurs both within and on top of the porous pavement. The problem is analogous to hill-slope hydrology of a thin aquifer where infiltration occurs rapidly and sheet flow is generated only when the aquifer is full. Common roadway features such as slope transitions and curvature make the drainage two-dimensional. A computer model was developed to study this coupled, unsteady process. The porous layer is modeled using the Boussinesq equation. The diffusion wave model is used for sheet flow over the pavement surface. This presentation summarizes the model’s development, shows that model results compare favorably to field measurements, and gives a case study in which the porous layer reduces the maximum sheet flow depth by 25% compared to conventional pavement.

  6. Evidence for the use of low-grade weirs in drainage ditches to improve nutrient reductions from agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The essential function of drainage ditches is to remove water from the agricultural landscape to avoid crop senescence through flooding and soil saturation. Commonly used slotted board risers provide drainage management strategies over the dormant season; however, by introducing innovative, low-gra...

  7. Reuse/disposal of agricultural drainage water with high levels of salinity and toxic trace elements in central California.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage waters in the western San Joaquin Valley of Central California contain high levels of salts, boron (B) and selenium (Se). Discharge of the drainage water directly into the Kesterson Reservoir in 1980's was hazardous to plants and wildlife. To investigate the plausibility of usi...

  8. Switching between hydrophobic and wettable conditions in soil: experiments to assess the influence of cracks, roots and subsurface drainage impedance

    NASA Astrophysics Data System (ADS)

    Urbanek, E.; Walsh, R. P. D.; Shakesby, R. A.

    2012-04-01

    Although much is known about soil hydrophobicity, assessments of the overall hydrological and erosional significance of the soil property in areas affected by it are greatly hampered by a lack of knowledge on switching between hydrophobic and hydrophilic states. This arises mainly because of (1) the destructive nature of methods of assessing hydrophobicity, (2) its often high local spatial variability and (3) difficulties of relating hydrophobicity results to meaningful soil moisture values. Also, very little is known about the influence which cracks and holes through hydrophobic soil and the presence or absence of subsurface impeding layers have on the 3D pattern and speed of hydrophobicity change during wetting and drying cycles. These issues form the focus of the present paper, which was carried out as part of the EU DESIRE Project. A laboratory experimental approach was adopted. Three different soils of equal initial hydrophibicity class when dry (18 % MED), but of contrasting texture and total carbon content, were investigated: (1) from the scrub-covered (dominated by Erica umbellata, Calluna vulgaris and Pterospartum tridentatum) Vale Torto catchment in Gois municipality, central Portugal (an area where the impacts of prescribed fire were being assessed); (2) soil around a Chamaecyparis lawsonia tree in South Wales; and (3) a vegetated coastal sand-dune location at Nicholaston, Gower Peninsula, South Wales. For the experiments, 106 samples of sieved (< 2 mm), dried soil were placed to a depth of 10 cm in standardized transparent pots (16.5 cm high, top diameter 16 cm, basal diameter 11 cm). Equal numbers of samples were prepared with either (i) five simulated holes, (ii) two simulated linear cracks (in both cases extending downwards to the sample base) and (iii) control soil samples without cracks or holes). Samples were also either (i) sealed at the base to create subsurface impeded drainage or (ii) provided with unimpeded basal drainage by insertion of

  9. Factors affecting removal of selenate in agricultural drainage water utilizing rice straw.

    PubMed

    Zhang, Yiqiang; Frankenberger, William T

    2003-04-15

    Microbial reduction of selenate [Se(VI)] to elemental selenium [Se(0)] is a useful technique for removing Se from agricultural drainage water. A series of batch experiments were conducted in the laboratory to determine the effects of pH (5-10), NO(3)(-) (100-500 mg/l), and SO(4)(2-) (0-5000 mg/l) on the removal of Se(VI) from drainage water with 1000 microg/l of Se(VI) and different amounts (1-4 g) of rice straw. Results showed that rice straw was very effective in creating a reducing environment (Eh=-205 to -355 mV) in the first 3 days of the pH-effect experiments. The optimum conditions for rapid Se(VI) removal from drainage water were a pH range of 6-9, high amounts of SO(4)(2-) (1000-5000 mg/l), low amounts of NO(3)(-) (100 mg/l) and high amounts of rice straw (3-4 g). Under these conditions, it took 5-7 days to reduce 93-95% of the added Se(VI) to Se(0). This study indicates that rice straw may be an inexpensive reducing agent to remediate Se(VI)-dominant San Joaquin Valley drainage water in the field.

  10. Information technology and innovative drainage management practices for selenium load reduction from irrigated agriculture to provide stakeholder assurances and meet contaminant mass loading policy objectives

    SciTech Connect

    Quinn, N.W.T.

    2009-10-15

    Many perceive the implementation of environmental regulatory policy, especially concerning non-point source pollution from irrigated agriculture, as being less efficient in the United States than in many other countries. This is partly a result of the stakeholder involvement process but is also a reflection of the inability to make effective use of Environmental Decision Support Systems (EDSS) to facilitate technical information exchange with stakeholders and to provide a forum for innovative ideas for controlling non-point source pollutant loading. This paper describes one of the success stories where a standardized Environmental Protection Agency (EPA) methodology was modified to better suit regulation of a trace element in agricultural subsurface drainage and information technology was developed to help guide stakeholders, provide assurances to the public and encourage innovation while improving compliance with State water quality objectives. The geographic focus of the paper is the western San Joaquin Valley where, in 1985, evapoconcentration of selenium in agricultural subsurface drainage water, diverted into large ponds within a federal wildlife refuge, caused teratogenecity in waterfowl embryos and in other sensitive wildlife species. The fallout from this environmental disaster was a concerted attempt by State and Federal water agencies to regulate non-point source loads of the trace element selenium. The complexity of selenium hydrogeochemistry, the difficulty and expense of selenium concentration monitoring and political discord between agricultural and environmental interests created challenges to the regulation process. Innovative policy and institutional constructs, supported by environmental monitoring and the web-based data management and dissemination systems, provided essential decision support, created opportunities for adaptive management and ultimately contributed to project success. The paper provides a retrospective on the contentious planning

  11. Modelling Water Flow, Heat Transport, Soil Freezing and Thawing, and Snow Processes in a Clayey, Subsurface Drained Agricultural Field

    NASA Astrophysics Data System (ADS)

    Warsta, L.; Turunen, M.; Koivusalo, H. J.; Paasonen-Kivekäs, M.; Karvonen, T.; Taskinen, A.

    2012-12-01

    Simulation of hydrological processes for the purposes of agricultural water management and protection in boreal environment requires description of winter time processes, including heat transport, soil freezing and thawing, and snow accumulation and melt. Finland is located north of the latitude of 60 degrees and has one third to one fourth of the total agricultural land area (2.3 milj. ha) on clay soils (> 30% of clay). Most of the clayey fields are subsurface drained to provide efficient drainage and to enable heavy machines to operate on the fields as soon as possible after the spring snowmelt. Generation of drainflow and surface runoff in cultivated fields leads to nutrient and sediment load, which forms the major share of the total load reaching surface waters at the national level. Water, suspended sediment, and soluble nutrients on clayey field surface are conveyed through the soil profile to the subsurface drains via macropore pathways as the clayey soil matrix is almost impermeable. The objective of the study was to develop the missing winter related processes into the FLUSH model, including soil heat transport, snow pack simulation and the effects of soil freezing and thawing on the soil hydraulic conductivity. FLUSH is an open source (MIT license), distributed, process-based model designed to simulate surface runoff and drainflow in clayey, subsurface drained agricultural fields. 2-D overland flow is described with the diffuse wave approximation of the Saint Venant equations and 3-D subsurface flow with a dual-permeability model. Both macropores and soil matrix are simulated with the Richards equation. Soil heat transport is described with a modified 3-D convection-diffusion equation. Runoff and groundwater data was available from different periods from January 1994 to April 1999 measured in a clayey, subsurface drained field section (3.6 ha) in southern Finland. Soil temperature data was collected in two locations (to a depth of 0.8 m) next to the

  12. Residues of endosulfan in surface and subsurface agricultural soil and its bioremediation.

    PubMed

    Odukkathil, Greeshma; Vasudevan, Namasivayam

    2016-01-01

    The persistence of many hydrophobic pesticides has been reported by various workers in various soil environments and its bioremediation is a major concern due to less bioavailability. In the present study, the pesticide residues in the surface and subsurface soil in an area of intense agricultural activity in Pakkam Village of Thiruvallur District, Tamilnadu, India, and its bioremediation using a novel bacterial consortium was investigated. Surface (0-15 cm) and subsurface soils (15-30 cm and 30-40 cm) were sampled, and pesticides in different layers of the soil were analyzed. Alpha endosulfan and beta endosulfan concentrations ranged from 1.42 to 3.4 mg/g and 1.28-3.1 mg/g in the surface soil, 0.6-1.4 mg/g and 0.3-0.6 mg/g in the subsurface soil (15-30 cm), and 0.9-1.5 mg/g and 0.34-1.3 mg/g in the subsurface soil (30-40 cm) respectively. Residues of other persistent pesticides were also detected in minor concentrations. These soil layers were subjected to bioremediation using a novel bacterial consortium under a simulated soil profile condition in a soil reactor. The complete removal of alpha and beta endosulfan was observed over 25 days. Residues of endosulfate were also detected during bioremediation, which was subsequently degraded on the 30th day. This study revealed the existence of endosulfan in the surface and subsurface soils and also proved that the removal of such a ubiquitous pesticide in the surface and subsurface environment can be achieved in the field by bioaugumenting a biosurfactant-producing bacterial consortium that degrades pesticides.

  13. Effect of replacing surface inlets with blind or gravel inlets on sediment and phosphorus subsurface drainage losses.

    PubMed

    Feyereisen, Gary W; Francesconi, Wendy; Smith, Douglas R; Papiernik, Sharon K; Krueger, Erik S; Wente, Christopher D

    2015-03-01

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for movement of sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine the reduction in drainage effluent total suspended sediment (TSS) and phosphorus (P) concentrations and loads when open surface inlets were replaced with blind (in gravel capped with 30 cm of soil) or gravel (in very coarse sand/fine gravel) inlets. In Indiana, a pair of closed depressions in adjacent fields was fitted with open inlet tile risers and blind inlets in 2005 and monitored for flow and water chemistry. Paired comparisons on a storm event basis during the growing season for years 2006 to 2013 showed that TSS loads were 40.4 and 14.4 kg ha event for tile risers and blind inlets, respectively. Total P (TP) and soluble reactive P (SRP) loads were 66 and 50% less for the blind inlets, respectively. In Minnesota, TSS and SRP concentrations were monitored for 3 yr before and after modification of 24 open inlets to gravel inlets in an unreplicated large-field on-farm study. Median TSS concentrations were 97 and 8.3 mg L and median SRP concentrations were 0.099 and 0.064 mg L for the open inlet and gravel inlet periods, respectively. Median TSS and SRP concentrations were elevated for snowmelt vs. non-snowmelt seasons for open and gravel inlets. Both replacement designs reduced suspended sediment and P concentrations and loads. The Indiana study suggests blind inlets will be effective beyond a 10-yr service life.

  14. Subsurface recharge to the Tesuque aquifer system from selected drainage basins along the western side of the Sangre de Cristo Mountains near Santa Fe, New Mexico

    USGS Publications Warehouse

    Wasiolek, Maryann

    1995-01-01

    Water budgets developed for basins of five streams draining the western side of the Sangre de Cristo Mountains in northern New Mexico indicate that subsurface inflow along the mountain front is recharging the Tesuque aquifer system of the Espanola Basin. Approximately 14,700 acre-feet of water per year, or 12.7 percent of average annual precipitation over the mountains, is calculated to leave the mountain block and enter the basin as subsurface recharge from the drainage basins of the Rio Nambe, Rio en Medio, Tesuque Creek, Little Tesuque Creek, and Santa Fe River. About 5,520 acre- feet per year, or about 12 percent of average annual precipitation, is calculated to enter from the Rio Nambe drainage basin; about 1,710 acre- feet per year, or about 15 percent of average annual precipitation, is calculated to enter from the Rio en Medio drainage basin; about 1,530 acre- feet, or about 10 percent of average annual precipi- tation, is calculated to enter from the Tesuque Creek drainage basin; about 1,790 acre-feet, or about 19 percent of average annual precipitation, is calculated to enter from the Little Tesuque Creek drainage basin; and about 4,170 acre-feet per year, or about 12 percent average annual precipitation, is calculated to enter from the Santa Fe River drainage basin. Calculated subsurface recharge values were used to define maximum fluxes permitted along the specified-flux boundary defining the mountain front of the Sangre De Cristo Mountains in a numerical computer model of the Tesuque aquifer system near Santa Fe, New Mexico.

  15. Assessment of waterlogging in agricultural megaprojects in the closed drainage basins of the Western Desert of Egypt

    NASA Astrophysics Data System (ADS)

    El Bastawesy, M.; Ramadan Ali, R.; Faid, A.; El Osta, M.

    2013-04-01

    This paper investigates the development of waterlogging in the cultivated and arable areas within typical dryland closed drainage basins (e.g. the Farafra and Baharia Oases), which are located in the Western Desert of Egypt. Multi-temporal remote sensing data of the Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+) were collected and processed to detect the land cover changes; cultivations, and the extent of water ponds and seepage channels. The Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) has been processed to delineate the catchment morphometrical parameters (i.e. drainage networks, catchment divides and surface areas of different basins) and to examine the spatial distribution of cultivated fields and their relation to the extracted drainage networks. The soil of these closed drainage basins is mainly shallow and lithic with high calcium carbonate content; therefore, the downward percolation of excess irrigation water is limited by the development of subsurface hardpan, which also saturates the upper layer of soil with water. The subsurface seepage from the newly cultivated areas in the Farafra Oasis has revealed the pattern of buried alluvial channels, which are waterlogged and outlined by the growth of diagnostic saline shrubs. Furthermore, the courses of these waterlogged channels are coinciding with their counterparts of the SRTM DEM, and the recent satellite images show that the surface playas in the downstream of these channels are partially occupied by water ponds. On the other hand, a large water pond has occupied the main playa and submerged the surrounding fields, as a large area has been cultivated within a relatively small closed drainage basin in the Baharia Oasis. The geomorphology of closed drainage basins has to be considered when planning for a new cultivation in dryland catchments to better control waterlogging hazards. The "dry-drainage" concept can be implemented as the drainage and seepage water can be

  16. Use of vegetated agricultural drainage ditches to decrease pesticide transport from tomato and alfalfa fields in California, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation and storm water runoff from agricultural fields has the potential to cause impairment to downstream aquatic receiving systems. Over the last several years, scientists have discovered the benefit of using edge-of-field practices, such as vegetated agricultural drainage ditches, in the mit...

  17. Removal of agricultural nitrate from tile-drainage effluent water using in-line bioreactors

    NASA Astrophysics Data System (ADS)

    Blowes, D. W.; Robertson, W. D.; Ptacek, C. J.; Merkley, C.

    1994-02-01

    Two 200-L fixed-bed bioreactors, containing porous-medium material of coarse sand and organic carbon (tree bark, wood chips and leaf compost), were used to treat NO 3 contamination from agricultural runoff. Flow from a farm-field drainage tile containing NO 3-N concentrations of 3-6 mg L -1 was successfully treated in the reactors (NO 3-N < 0.02 mg L -1) at a rate of 10-60 L day -1 over a 1-yr period. Treatment occurs by anaerobic denitrification promoted by the added solid-phase organic carbon. Because the reactor design is simple, economical to construct and maintenance free, it may provide a practical solution to the problem of treating redox-sensitive contaminants, such as NO 3, in agricultural runoff.

  18. Chemical status of selenium in evaporation basins for disposal of agricultural drainage.

    PubMed

    Gao, S; Tanji, K K; Dahlgren, R A; Ryu, J; Herbel, M J; Higashi, R M

    2007-09-01

    Evaporation basins (or ponds) are the most commonly used facilities for disposal of selenium-laden saline agricultural drainage in the closed hydrologic basin portion of the San Joaquin Valley, California. However concerns remain for potential risk from selenium (Se) toxicity to water fowl in these evaporation basins. In this study, we examined the chemical status of Se in both waters and sediments in two currently operating evaporation pond facilities in the Tulare Lake Drainage District. Some of the saline ponds have been colonized by brine-shrimp (Artemia), which have been harvested since 2001. We evaluated Se concentration and speciation, including selenate [Se(VI)], selenite [Se(IV)], and organic Se [org-Se or Se(-II)] in waters and sediment extracts, and fractionation (soluble, adsorbed, organic matter (OM)-associated, and Se(0) and other resistant forms) in sediments and organic-rich surface detrital layers from the decay of algal blooms. Selenium in ponds without vascular plants exhibited similar behavior to wetlands with vascular plant present, indicating that similar Se transformation processes and mechanisms had resulted in Se immobilization and an increase of reduced Se species [Se(IV), org-Se, and Se(0)] from Se(VI)-dominated input waters. Selenium concentrations in most pond waters were significantly lower than the influent drainage water. This decrease of dissolved Se concentration was accompanied by the increase of reduced Se species. Selenium accumulated preferentially in sediments of the initial pond cell receiving drainage water. Brine-shrimp harvesting activities did not affect Se speciation but may have reduced Se accumulation in surface detrital and sediments.

  19. A dynamic model of soil salinity and drainage generation in irrigated agriculture: A framework for policy analysis

    NASA Astrophysics Data System (ADS)

    Dinar, Ariel; Aillery, Marcel P.; Moore, Michael R.

    1993-06-01

    This paper presents a dynamic model of irrigated agriculture that accounts for drainage generation and salinity accumulation. Critical model relationships involving crop production, soil salinity, and irrigation drainage are based on newly estimated functions derived from lysimeter field tests. The model allocates land and water inputs over time based on an intertemporal profit maximization objective function and soil salinity accumulation process. The model is applied to conditions in the San Joaquin Valley of California, where environmental degradation from irrigation drainage has become a policy issue. Findings indicate that in the absence of regulation, drainage volumes increase over time before reaching a steady state as increased quantities of water are allocated to leaching soil salts. The model is used to evaluate alternative drainage abatement scenarios involving drainage quotas and taxes, water supply quotas and taxes, and irrigation technology subsidies. In our example, direct drainage policies are more cost-effective in reducing drainage than policies operating indirectly through surface water use, although differences in cost efficiency are relatively small. In some cases, efforts to control drainage may result in increased soil salinity accumulation, with implications for long-term cropland productivity. While policy adjustments may alter the direction and duration of convergence to a steady state, findings suggest that a dynamic model specification may not be necessary due to rapid convergence to a comon steady state under selected scenarios.

  20. Agricultural pesticides in six drainage basins used for public water supply in New Jersey, 1990

    USGS Publications Warehouse

    Ivahnenko, Tamara; Buxton, D.E.

    1994-01-01

    A reconnaissance study of six drainage basins in New Jersey was conducted to evaluate the presence of pesticides from agricultural runoff in surface water. In the first phase of the study, surface-water public-supply drainage basins throughout New Jersey that could be affected by pesticide applications were identified by use of a Geographic Information System. Six basins--Lower Mine Hill Reservoir, South Branch of the Raritan River, Main Branch of the Raritan River, Millstone River, Manasquan River, and Matchaponix Brook--were selected as those most likely to be affected by pesticides on the basis of calculated pesticide-application rates and percentage of agricultural land. The second phase of the project was a short-term water-quality reconnaissance of the six drainage basins to determine whether pesticides were present in the surface waters. Twenty-eight surface-water samples (22 water-quality samples, 3 sequentially collected samples, and 3 trip blanks), and 6 samples from water-treatment facilities were collected. Excluding trip blanks, samples from water-treatment facilities, and sequentially collected samples, the pesticides detected in the samples and the percentage of samples in which they were detected, were as follows: atrazine and metolachlor, 86 percent; alachlor, 55 percent; simazine, 45 percent; diazinon, 27 percent; cyanazine and carbaryl, 23 percent; linuron and isophenfos, 9 percent; and chlorpyrifos, 5 percent.Diazinon, detected in one stormflow sample collected from Matchaponix Brook on August 6, 1990, was the only compound to exceed the U.S. Environmental Protection Agency's recommended Lifetime Health Advisory Limit. Correlation between ranked metolachlor concentrations and ranked flow rates was high, and 25 percent of the variance in metolachlor concentrations can be attributed to variations in flow rate. Pesticide residues were detected in samples of pretreated and treated water from water-treatment facilities. Concentrations of all

  1. Assessment of drainage nitrogen losses on a yield-scaled basis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface nitrogen (N) losses represent a major environmental concern in agriculture, particularly from fields containing artificial drainage to prevent saturated soil conditions and increase crop production. To develop sustainable intensification strategies and achieve high yields with minimal en...

  2. Selenium stable isotope ratios in California agricultural drainage water management systems

    USGS Publications Warehouse

    Herbel, M.J.; Johnson, T.M.; Tanji, K.K.; Gao, S.; Bullen, T.D.

    2002-01-01

    Selenium stable isotope ratios are known to shift in predictable ways during various microbial, chemical, and biological processes, and can be used to better understand Se cycling in contaminated environments. In this study we used Se stable isotopes to discern the mechanisms controlling the transformation of oxidized, aqueous forms of Se to reduced, insoluble forms in sediments of Se-affected environments. We measured 80Se/76Se in surface waters, shallow ground waters, evaporites, digested plants and sediments, and sequential extracts from several sites where agricultural drainage water is processed in the San Joaquin Valley of California. Selenium isotope analyses of samples obtained from the Tulare Lake Drainage District flow-through wetland reveal small isotopic contrasts (mean difference 0.7%o) between surface water and reduced Se species in the underlying sediments. Selenium in aquatic macrophytes was very similar isotopically to the NaOH and Na2SO3 sediment extracts designed to recover soluble organic Se and Se(O), respectively. For the integrated on-farm drainage management sites, evaporite salts were slightly (approximately 0.6%o) enriched in the heavier isotope relative to the inferred parent waters, whereas surface soils were slightly (approximately 1.4%o) depleted. Bacterial or chemical reduction of Se(VI) or Se(IV) may be occurring at these sites, but the small isotopic contrasts suggest that other, less isotopically fractionating mechanisms are responsible for accumulation of reduced forms in the sediments. These findings provide evidence that Se assimilation by plants and algae followed by deposition and mineralization is the dominant transformation pathway responsible for accumulation of reduced forms of Se in the wetland sediments.

  3. Capture and characterization of particulate phosphorus from farm drainage waters in the Everglades Agricultural Area

    NASA Astrophysics Data System (ADS)

    Bhadha, J. H.; Lang, T.; Daroub, S.

    2012-12-01

    The buildup of highly labile, organic, phosphorus (P)-enriched sediments in farms canals within the Everglades Agricultural Area (EAA) has been associated with the production of floating aquatic vegetation. During drainage events, these sediments are susceptible to transport and contribute to the overall P load. In order to evaluate the total P load exiting the farm canals, a settling tank experiment was conducted to capture the sediments during drainage events from eight farms. Drainage water was channelized through two 200L polypropylene collection tanks which allowed sediments to settle at the bottom based on its particle size. Water was carefully siphoned out of the tanks and the sediments collected for analyses. A five step P-fractionation process was used to distinguish organic (o) and inorganic (i) forms of P: KCl extractable P, NaOH extractable P, HCl extractable P, and residual P. The KCl-Pi fraction represents the labile Pi that is water soluble and exchangeable (loosely adsorbed); NaOH extractable P represents Fe- and Al- bound inorganic P (NaOH-Pi) and organic P associated with humic and fulvic acids (NaOH-Po). The HCl-Pi fraction includes Ca- and Mg- bound P, while Residue-P represents recalcitrant organic P compounds and P bound to minerals. The sediments were also used to conduct a P-flux study under both aerobic and anaerobic conditions. Our goal is to provide growers with vital information and insight into P loading that will help them in their efforts to reduce off-farm P loads in the EAA.

  4. Selenium stable isotope ratios in California agricultural drainage water management systems.

    PubMed

    Herbel, Mitchell J; Johnson, Thomas M; Tanji, Kenneth K; Gao, Suduan; Bullen, Thomas D

    2002-01-01

    Selenium stable isotope ratios are known to shift in predictable ways during various microbial, chemical, and biological processes, and can be used to better understand Se cycling in contaminated environments. In this study we used Se stable isotopes to discern the mechanisms controlling the transformation of oxidized, aqueous forms of Se to reduced, insoluble forms in sediments of Se-affected environments. We measured 80Se/76Se in surface waters, shallow ground waters, evaporites, digested plants and sediments, and sequential extracts from several sites where agricultural drainage water is processed in the San Joaquin Valley of California. Selenium isotope analyses of samples obtained from the Tulare Lake Drainage District flow-through wetland reveal small isotopic contrasts (mean difference 0.7%) between surface water and reduced Se species in the underlying sediments. Selenium in aquatic macrophytes was very similar isotopically to the NaOH and Na2SO3 sediment extracts designed to recover soluble organic Se and Se(0), respectively. For the integrated on-farm drainage management sites, evaporite salts were slightly (approximately 0.6%) enriched in the heavier isotope relative to the inferred parent waters, whereas surface soils were slightly (approximately 1.4%) depleted. Bacterial or chemical reduction of Se(VI) or Se(IV) may be occurring at these sites, but the small isotopic contrasts suggest that other, less isotopically fractionating mechanisms are responsible for accumulation of reduced forms in the sediments. These findings provide evidence that Se assimilation by plants and algae followed by deposition and mineralization is the dominant transformation pathway responsible for accumulation of reduced forms of Se in the wetland sediments.

  5. Use of vegetated agricultural drainage ditches to decrease pesticide transport from tomato and alfalfa fields in California: runoff toxicity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was performed to investigate the potential of vegetated drainage ditches for mitigating the impact of agricultural irrigation runoff on downstream aquatic ecosystems. Water column toxicity to larval fathead minnow (Pimephales promelas), and the amphipod, Hyalella azteca, was measured for ...

  6. Organic matter removal from saline agricultural drainage wastewater using a moving bed biofilm reactor.

    PubMed

    Ateia, Mohamed; Nasr, Mahmoud; Yoshimura, Chihiro; Fujii, Manabu

    2015-01-01

    We investigated the effect of salinity on the removal of organics and ammonium from agricultural drainage wastewater (ADW) using moving bed biofilm reactors (MBBRs). Under the typical salinity level of ADW (total dissolved solids (TDS) concentration up to 2.5 g·L(-1)), microorganisms were acclimated for 40 days on plastic carriers and a stable slime layer of attached biofilm was formed. Next, six batch mode MBBRs were set up and run under different salinity conditions (0.2-20 g-TDS·L(-1)). The removal efficiency of chemical oxygen demand (COD) and ammonium-nitrogen (NH4-N) in 6 hours decreased from 98 and 68% to 64 and 21% with increasing salt concentrations from 2.5 to 20 g-TDS·L(-1), respectively. In addition, at decreasing salt levels of 0.2 g-TDS·L(-1), both COD removal and nitrification were slightly lowered. Kinetic analysis indicated that the first-order reaction rate constant (k1) and specific substrate utilization rate (U) with respect to the COD removal remained relatively constant (10.9-11.0 d(-1) and 13.1-16.1 g-COD-removed.g-biomass(-1)·d(-1), respectively) at the salinity range of 2.5-5.0 g-TDS·L(-1). In this study, the treated wastewater met the standard criteria of organic concentration for reuse in agricultural purposes, and the system performance remained relatively constant at the salinity range of typical ADW.

  7. Kinetics of aerobic and anaerobic biomineralization of atrazine in surface and subsurface agricultural soils in Ohio.

    PubMed

    Tuovinen, Olli H; Deshmukh, Vaidehi; Özkaya, Bestamin; Radosevich, Mark

    2015-01-01

    The purpose of this study was to assess atrazine mineralization in surface and subsurface samples retrieved from vertical cores of agricultural soils from two farm sites in Ohio. The Defiance site (NW-Ohio) was on soybean-corn rotation and Piketon (S-Ohio) was on continuous corn cultivation. Both sites had a history of atrazine application for at least a couple of decades. The clay fraction increased at the Defiance site and the organic matter and total N content decreased with depth at both sites. Mineralization of atrazine was assessed by measurement of (14)CO2 during incubation of soil samples with [U-ring-(14)C]-atrazine. Abiotic mineralization was negligible in all soil samples. Aerobic mineralization rate constants declined and the corresponding half-lives increased with depth at the Defiance site. Anaerobic mineralization (supplemented with nitrate) was mostly below the detection at the Defiance site. In Piketon samples, the kinetic parameters of aerobic and anaerobic biomineralization of atrazine displayed considerable scatter among replicate cores and duplicate biometers. In general, this study concludes that data especially for anaerobic biomineralization of atrazine can be more variable as compared to aerobic conditions and cannot be extrapolated from one agricultural site to another.

  8. The use of constructed wetlands for removal of pesticides from agricultural runoff and drainage: a review.

    PubMed

    Vymazal, Jan; Březinová, Tereza

    2015-02-01

    Pesticides are used in modern agriculture to increase crop yields, but they may pose a serious threat to aquatic ecosystems. Pesticides may enter water bodies through diffuse and point sources, but diffuse sources are probably the most important. Among diffuse pollution, surface runoff and erosion, leaching and drainage represent the major pathways. The most commonly used mitigation techniques to prevent pesticide input into water bodies include edge-of-field and riparian buffer strips, vegetated ditches and constructed wetlands. The first attempts to use wetland macrophytes for pesticide removal were carried out as early as the 1970s, but only in the last decade have constructed wetlands for pesticide mitigation become widespread. The paper summarizes 47 studies in which removal of 87 pesticides was monitored. The survey revealed that constructed wetlands with free water surface are the most commonly used type. Also, it has been identified that removal of pesticides is highly variable. The results of the survey revealed that the highest pesticide removal was achieved for pesticides of the organochlorine, strobilurin/strobin, organosphosphate and pyrethroid groups while the lowest removals were observed for pesticides of the triazinone, aryloxyalkanoic acid and urea groups. The removal of pesticides generally increases with increasing value of KOC but the relationship is not strong.

  9. Dielectric spectroscopic studies on the water hyacinth plant collected from agriculture drainage.

    PubMed

    Mahani, Ragab; Atia, Fatma; Al Neklawy, Mohammed M; Fahem, Amin

    2016-06-05

    The present paper aims to investigate the sensitivity of dielectric spectroscopy to changes in concentrations of pollutants (heavy metals and metal oxides) uptake by the water hyacinth plant collected from agriculture wastewater drainage. The measurements were carried out on the dried root and shoot plant parts before and after subjecting to different microwave heating powers for different times. Dielectric properties of the untreated root were investigated at temperature range (30-90°C). X-ray fluorescence spectroscopy (XRF) results showed that the concentration of metals and metals oxides are higher in plant root than in plant shoot. Accordingly, the obtained dielectric properties were found to depend on the applied electric field frequency, magnitude of heating power as well as concentrations of pollutants. Analysis of experimental data represented by the imaginary part of the dielectric modulus M″ (ω) revealed to the presence of three different relaxation processes. The lower frequency relaxation process was associated to charge carriers conduction whereas those appeared at higher frequencies were associated to different types of interfacial polarization. The plant ability for removing heavy metals and metal oxides from the aquatic environments would be enhanced upon subjecting to microwave heating power with 400 W for 30 min.

  10. Dielectric spectroscopic studies on the water hyacinth plant collected from agriculture drainage

    NASA Astrophysics Data System (ADS)

    Mahani, Ragab; Atia, Fatma; Al Neklawy, Mohammed M.; Fahem, Amin

    2016-06-01

    The present paper aims to investigate the sensitivity of dielectric spectroscopy to changes in concentrations of pollutants (heavy metals and metal oxides) uptake by the water hyacinth plant collected from agriculture wastewater drainage. The measurements were carried out on the dried root and shoot plant parts before and after subjecting to different microwave heating powers for different times. Dielectric properties of the untreated root were investigated at temperature range (30-90 °C). X-ray fluorescence spectroscopy (XRF) results showed that the concentration of metals and metals oxides are higher in plant root than in plant shoot. Accordingly, the obtained dielectric properties were found to depend on the applied electric field frequency, magnitude of heating power as well as concentrations of pollutants. Analysis of experimental data represented by the imaginary part of the dielectric modulus M″ (ω) revealed to the presence of three different relaxation processes. The lower frequency relaxation process was associated to charge carriers conduction whereas those appeared at higher frequencies were associated to different types of interfacial polarization. The plant ability for removing heavy metals and metal oxides from the aquatic environments would be enhanced upon subjecting to microwave heating power with 400 W for 30 min.

  11. Determination of commonly used polar herbicides in agricultural drainage waters in Australia by HPLC.

    PubMed

    Tran, Anh T K; Hyne, Ross V; Doble, Philip

    2007-03-01

    The present study describes the application of different extraction techniques for the preconcentration of ten commonly found acidic and non-acidic polar herbicides (2,4-D, atrazine, bensulfuron-methyl, clomazone, dicamba, diuron, MCPA, metolachlor, simazine and triclopyr) in the aqueous environment. Liquid-liquid extraction (LLE) with dichloromethane, solid-phase extraction (SPE) using Oasis HLB cartridges or SBD-XC Empore disks were compared for extraction efficiency of these herbicides in different matrices, especially water samples from contaminated agricultural drainage water containing high concentrations of particulate matter. Herbicides were separated and quantified by high performance liquid chromatography (HPLC) with an ultraviolet detector. SPE using SDB-XC Empore disks was applied to determine target herbicides in the Murrumbidgee Irrigation Area (NSW, Australia) during a two-week survey from October 2005 to November 2005. The daily aqueous concentrations of herbicides from 24-h composite samples detected at two sites increased after run-off from a storm event and were in the range of: 0.1-17.8 microg l(-1), < 0.1-0.9 microg l(-1) and 0.2-17.8 microg l(-1) at site 1; < 0.1-3.5 microg l(-1), < 0.1-0.2 microg l(-1) and < 0.2-3.2 microg l(-1) at site 2 for simazine, atrazine and diuron, respectively.

  12. Baffled duck weed pond system for treatment of agricultural drainage water containing pharmaceuticals.

    PubMed

    Bassuney, Doaa; Tawfik, Ahmed

    2017-02-03

    The aim of the study is to assess the efficiency of a novel bioremediation system namely baffled duck weed pond (BDWP) system for treatment of agricultural drainage water containing pharmaceuticals at different hydraulic retention times (HRTs). The removal efficiencies of acetaminophen (ACT), amoxicillin (AMX) and ampicillin (AMP) increased from 69.3±8.6 to 87.3 ±3.5%, from 52.9±9.4 to 82.9±5.2% and from 55.3±7.9 to 90.6±2.8% at increasing the HRT from 6 to 8 d., respectively. However, ACT, AMX and AMP removal efficiencies were slightly improved at increasing the HRT from 8 to 12 d. Diclofenac (DFC) removal efficiencies amounted to 56.6 ±11.6, 55.7±11.9 and 28.3 ±12.9% at an HRTs of 12, 8 and 6d., respectively. The results showed no relationship between the uptake / absorption of pharmaceuticals fractions and BOD5/COD ratio except ACT where R(2) was 0.84. The effect of COD/ N ratio on the removal efficiency of pharmaceuticals fractions was slight. Additional removal of pharmaceuticals fractions and nitrification was occurred in carrier sponge media situated in the last compartment of the BDWP.

  13. Reclaiming agricultural drainage water with nanofiltration membranes: Imperial Valley, California, USA

    USGS Publications Warehouse

    Kharaka, Y.K.; Schroeder, R.A.; Setmire, J.G.; ,

    2003-01-01

    We conducted pilot-scale field experiments using nanofiltration membranes to lower the salinity and remove Se, As and other toxic contaminants from saline agricultural wastewater in the Imperial Valley, California, USA. Farmlands in the desert climate (rainfall - 7.4 cm/a) of Imperial Valley cover -200,000 ha that are irrigated with water (-1.7 km3 annually) imported from the Colorado River. The salinity (-850 mg/L) and concentration of Se (-2.5 ??g/L) in the Colorado River water are high and evapotranpiration further concentrates salts in irrigation drainage water, reaching salinities of 3,000-15,000 mg/L TDS and a median Se value of -30 ??g/L. Experiments were conducted with two commercially available nanofiltration membranes, using drainage water of varying composition, and with or without the addition of organic precipitation inhibitors. Results show that these membranes selectively remove more than 95% of Se, SO4, Mo, U and DOC, and -30% of As from this wastewater. Low percentages of Cl, NO3 and HCO3, with enough cations to maintain electrical neutrality also were removed. The product water treated by these membranes comprised more than 90% of the wastewater tested. Results indicate that the treated product water from the Alamo River likely will have less than 0.2 ??g/L Se, salinity of 300-500 mg/L TDS and other chemical concentrations that meet the water quality criteria for irrigation and potable use. Because acceptability is a major issue for providing treated wastewater to urban centers, it may be prudent to use the reclaimed water for irrigation and creation of lower salinity wetlands near the Salton Sea; an equivalent volume of Colorado River water can then be diverted for the use of increasing populations of San Diego and other urban centers in southern California. Nanofiltration membranes yield greater reclaimed-water output and require lower pressure and less pretreatment, and therefore are generally more cost effective than traditional reverse

  14. Hydrologic and biogeochemical controls of river subsurface solutes under agriculturally enhanced ground water flow

    USGS Publications Warehouse

    Wildman, R.A.; Domagalski, J.L.; Hering, J.G.

    2009-01-01

    The relative influences of hydrologic processes and biogeochemistry on the transport and retention of minor solutes were compared in the riverbed of the lower Merced River (California, USA). The subsurface of this reach receives ground water discharge and surface water infiltration due to an altered hydraulic setting resulting from agricultural irrigation. Filtered ground water samples were collected from 30 drive point locations in March, June, and October 2004. Hydrologic processes, described previously, were verified by observations of bromine concentrations; manganese was used to indicate redox conditions. The separate responses of the minor solutes strontium, barium, uranium, and phosphorus to these influences were examined. Correlation and principal component analyses indicate that hydrologic processes dominate the distribution of trace elements in the ground water. Redox conditions appear to be independent of hydrologic processes and account for most of the remaining data variability. With some variability, major processes are consistent in two sampling transects separated by 100 m. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  15. Comparison of the performances of DRAINMOD-NII and ADAPT models in simulating nitrate losses from subsurface drainage systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adequate knowledge on the movement of nitrate under different subsurface (tile) drain configurations and management practices in the U.S. Midwest, is essential for developing remedial measures for reducing hypoxic conditions in the Gulf of Mexico. In this study, DRAINMOD-NII, a daily time-step soil ...

  16. Selenium and nitrate removal from agricultural drainage using the AIWPS(R) technology

    SciTech Connect

    Green, F.B.; Lundquist, T.J.; Quinn, N.W.T.; Zarate, M.A.; Zubieta, I.X.; Oswald, W.J.

    2003-01-02

    Monthly Maximum Discharge Limits (MMDL) have been established for selenium in irrigation drainage by the State of California and the U.S. Environmental Protection Agency following observations of avian teratogenesis at the Kesterson Reservoir in the San Joaquin Valley of California. As a result of these and other adverse effects, farmers and drainage districts on the western side of the San Joaquin Valley must reduce selenium concentrations in irrigation, drainage discharged to the San Joaquin River. Drainage treatment will be required in the near future to meet existing MMDL and future Total Maximum Discharge Limits (TMDL) for the San Joaquin River. A 0.4-hectare Algal Bacterial Selenium Removal (ABSR) Facility was designed and constructed at the Panoche Drainage District in 1995 and 1996 using the Advanced Integrated Wastewater Pond Systems (R) or AIWPS (R) Technology. Each of two physically identical systems combined a Reduction Pond (RP) with a shallow, peripheral algal High Rate Pond (HRP). A Dissolved Air Flotation (DAF) unit and a slow sand filter were used to remove particulate selenium from the effluent of each system. The two systems were operated under different modes of operation and the bacterial substrate varied in each system. The rates of nitrate and selenium removal were compared. Microalgae were harvested using DAF and used as a carbon-rich substrate for nitrate- and selenate-reducing bacteria. Mass removals of total soluble selenium of 77 percent or greater were achieved over a three-year period. Nitrate and selenate were removed by assimilatory and dissimilatory bacterial reduction, and nitrate was also removed by algal assimilation. The final removal of particulate selenium is the focus of ongoing investigations. The removal of particulate selenium is expected to increase the overall removal of selenium to greater than 90 percent and would allow farmers and drainage districts to discharge irrigation drainage in compliance with regulatory

  17. Effects of agriculture, housing development, and industry on water quality in a small drainage basin, Bushkill Creek, Pennsylvania

    SciTech Connect

    Germanoski, D. . Geology Dept.); Braunwell, P. . Dept. of Environmental Science and Engineering); Coykendall, J.P. ); Kelsey, J. . Dept. of Environmental Chemistry)

    1993-03-01

    Beginning in 1989, three successive studies have focused on the effects of various land use activities on water quality in the Bushkill Creek. Bushkill Creek is located in Northampton County, Pennsylvania and is a tributary to the Delaware River. Bushkill Creek has a drainage area of 206 km[sup 2]. The watershed is underlain by slate and shale units of the Martinsburg Formation and Ordovician carbonate rocks including the Jacksonburg Formation, the Beeckmantown Group, and the Allentown Formations. The authors have been collecting water quality data in the Bushkill Creek drainage basin over a three-year period (1989--1992) in order to determine the general quality of the water and to assess the impact of various land use and industrial activities on water quality. The authors' initial investigation focused on the impact of several potential point sources of contamination in the lower, more heavily industrialized, portion of the Bushkill Creek. Water samples were analyzed for ammonia, chromium (at one site only), nitrate, nitrite, orthophosphate, sulfate, and gasoline (at one site only). The results of that research indicated that background concentrations of nitrates and sulfates were quite high. Therefore, subsequent investigations have focused on the potential impact of agricultural activity and housing development in the upper portion of the Bushkill drainage basin. In particular: (1) petroleum contamination was occurring as a point source in the lower Bushkill drainage, (2) nitrate concentrations in the creek have increased during the past twenty years, most likely as the result of agricultural activity and housing development, (3) sulfate loading into the Bushkill Creek occurs from the Little Bushkill Creek, and (4) the high sulfate concentration in the Little Bushkill Creek originates in the vicinity of a slate quarry.

  18. Removal of phosphorus from agricultural wastewaters using adsorption media prepared from acid mine drainage sludge.

    PubMed

    Sibrell, Philip L; Montgomery, Gary A; Ritenour, Kelsey L; Tucker, Travis W

    2009-05-01

    Excess phosphorus in wastewaters promotes eutrophication in receiving waterways. A cost-effective method for the removal of phosphorus from water would significantly reduce the impact of such wastewaters on the environment. Acid mine drainage sludge is a waste product produced by the neutralization of acid mine drainage, and consists mainly of the same metal hydroxides used in traditional wastewater treatment for the removal of phosphorus. In this paper, we describe a method for the drying and pelletization of acid mine drainage sludge that results in a particulate media, which we have termed Ferroxysorb, for the removal of phosphorus from wastewater in an efficient packed bed contactor. Adsorption capacities are high, and kinetics rapid, such that a contact time of less than 5 min is sufficient for removal of 60-90% of the phosphorus, depending on the feed concentration and time in service. In addition, the adsorption capacity of the Ferroxysorb media was increased dramatically by using two columns in an alternating sequence so that each sludge bed receives alternating rest and adsorption cycles. A stripping procedure based on treatment with dilute sodium hydroxide was also developed that allows for recovery of the P from the media, with the possibility of generating a marketable fertilizer product. These results indicate that acid mine drainage sludges -- hitherto thought of as undesirable wastes -- can be used to remove phosphorus from wastewater, thus offsetting a portion of acid mine drainage treatment costs while at the same time improving water quality in sensitive watersheds.

  19. Removal of phosphorus from agricultural wastewaters using adsorption media prepared from acid mine drainage sludge

    USGS Publications Warehouse

    Sibrell, Philip L.; Montgomery, Gary A.; Ritenour, Kelsey L.; Tucker, Travis W.

    2009-01-01

    Excess phosphorus in wastewaters promotes eutrophication in receiving waterways. A??cost-effective method for the removal of phosphorus from water would significantly reduce the impact of such wastewaters on the environment. Acid mine drainage sludge is a waste product produced by the neutralization of acid mine drainage, and consists mainly of the same metal hydroxides used in traditional wastewater treatment for the removal of phosphorus. In this paper, we describe a method for the drying and pelletization of acid mine drainage sludge that results in a particulate media, which we have termed Ferroxysorb, for the removal of phosphorus from wastewater in an efficient packed bed contactor. Adsorption capacities are high, and kinetics rapid, such that a contact time of less than 5 min is sufficient for removal of 60-90% of the phosphorus, depending on the feed concentration and time in service. In addition, the adsorption capacity of the Ferroxysorb media was increased dramatically by using two columns in an alternating sequence so that each sludge bed receives alternating rest and adsorption cycles. A stripping procedure based on treatment with dilute sodium hydroxide was also developed that allows for recovery of the P from the media, with the possibility of generating a marketable fertilizer product. These results indicate that acid mine drainage sludges - hitherto thought of as undesirable wastes - can be used to remove phosphorus from wastewater, thus offsetting a portion of acid mine drainage treatment costs while at the same time improving water quality in sensitive watersheds.

  20. Nitrate removal from agricultural drainage ditch sediments with amendments of organic carbon: Potential for an innovative best management practice

    USGS Publications Warehouse

    Faust, Derek R.; Kröger, Robert; Miranda, Leandro E.; Rush, Scott A.

    2016-01-01

    Agricultural fertilizer applications have resulted in loading of nutrients to agricultural drainage ditches in the Lower Mississippi Alluvial Valley. The purpose of this study was to determine effects of dissolved organic carbon (DOC) and particulate organic carbon (POC) amendments on nitrate-nitrogen (NO3−-N) removal from overlying water, pore water, and sediment of an agricultural drainage ditch. Two experiments were conducted. In experiment 1, control (i.e., no amendment), DOC, and POC treatments were applied in laboratory microcosms for time intervals of 3, 7, 14, and 28 days. In experiment 2, control, DOC, and POC treatments were applied in microcosms at C/N ratios of 5:1, 10:1, 15:1, and 20:1. There were statistically significant effects of organic carbon amendments in experiment 1 (F2,71 = 27.1, P < 0.001) and experiment 2 (F2,53 = 39.1, P < 0.001), time (F1,71 = 14.5, P < 0.001) in experiment 1, and C/N ratio (F1,53 = 36.5, P < 0.001) in experiment 2. NO3−-N removal varied from 60 to 100 % in overlying water among all treatments. The lowest NO3−-N removals in experiment 1 were observed in the control at 14 and 28 days, which were significantly less than in DOC and POC 14- and 28-day treatments. In experiment 2, significantly less NO3−-N was removed in overlying water of the control compared to DOC and POC treatments at all C/N ratios. Amendments of DOC and POC made to drainage ditch sediment: (1) increased NO3−-N removal, especially over longer time intervals (14 to 28 days); (2) increased NO3−-N removal, regardless of C/N ratio; and (3) NO3−-N removal was best at a 5:1 C/N ratio. This study provides support for continued investigation on the use of organic carbon amendments as a best management practice for NO3−-N removal in agricultural drainage ditches.

  1. Contributions of systematic tile drainage to watershed scale phosphorus transport

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) transport from agricultural fields continues be a focal point for addressing harmful algal blooms (HABs) and nuisance algae in freshwater systems throughout the world. In humid, poorly drained regions, attention has turned to P delivery through subsurface tile drainage. Research on th...

  2. Nutrient export in tile drainage: Comparing manure injection to fertigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface tile drainage of agricultural land is implicated as a major source of nutrients to the Mississippi River. To protect water quality, land application of manure should maximize crop nutrient use and minimize nutrient loss. Weather constraints and regulations restrict the period during which...

  3. The feasibility of applying immature yard-waste compost to remove nitrate from agricultural drainage effluents: A preliminary assessment

    USGS Publications Warehouse

    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.

  4. Five year water and nitrogen balance for a constructed surface flow wetland treating agricultural drainage waters.

    PubMed

    Borin, Maurizio; Tocchetto, Davide

    2007-07-15

    The performance of a constructed surface flow wetland in reducing diffuse N pollution coming from croplands is being investigated in an ongoing experiment, begun in 1998 in NE Italy. The 0.32 ha wetland is vegetated with Phragmites australis (Cav.) Trin. and Typha latifolia (L.). It receives drainage water from 6 ha of land managed for an experiment on drainage systems, where maize, sugarbeet, winter wheat and soybean are cultivated. During the period 1998-2002, the wetland received from 4698 to 8412 mm of water per year (on average, about 9 times the environmental rainfall); its water regimen was discontinuous and flooding occurred on a variable number of days per year (from 13 to 126). Nitric nitrogen was the most important form of element load. Its concentration in the inflow water over time was rather discontinuous, with median values ranging from 0.2 (in 2001) to 4.5 (in 2000) mg L(-1). Inflow nitric N concentrations were occasionally in the 5-15 mg L(-1) range. Concentrations reduced passing through the wetland, with a more evident effect in the last year. Over 5 years, the wetland received slightly more than 2000 kg ha(-1) of nitrogen, 87% in nitric form mostly from farmland drainage. The remaining 13% of N was applied as organic slurry directly onto the wetland, with 5 distributions during 1998 to assess wetland performance in treating occasional organic loads. Field drainage loads had a discontinuous time pattern and occurred mostly during autumn-winter, with the exception of the 2001-2002 season which was a very dry. The wetland discharged 206 kg ha(-1) of N, over the 5-year period, with an apparent removal efficiency of about 90%. The disappearance was mostly due to plant uptake (1110 kg ha(-1)) and soil accumulation (570 kg ha(-1)), with the contribution of denitrification being estimated at around 7%.

  5. Evaluation of management options for disposal of salt and trace element laden agricultural drainage water from the Fallon Indian Reservation, Fallon, Nevada

    SciTech Connect

    Tokunaga, Tetsu; Benson, S.

    1991-03-01

    This is the final report describing work performed on the Fallon Indian Reservation by the Earth Sciences Division at Lawrence Berkeley Laboratory during FY90. These investigations were initiated at the request of the United States Bureau of Reclamation in response to recent concerns regarding disposal of agriculture drainage water from the Reservation. The Reservation is transected by numerous irrigation and drainage canals, including the TJ Drain. Recent investigations by the US Fish and Wildlife Service have demonstrated that water in the TJ Drain is toxic to several aquatic indicator organisms, including bluegills, fathead minnows and daphnids. This information, coupled with recent die-offs of fish and birds, has lead to concern about continued discharge of TJ Drain water into local surface waters. In late 1990, plans for closing the TJ Drain and providing for alternative drainage were initiated. We aim to provide information for assessing options fro disposal of agricultural drainage water from the Reservation. In particular, our studies focuses on irrigation and drainage of lands currently serviced by the TJ Drain. Options for continued irrigation and drainage of the Reservation fall broadly into two categories: options that provide an alternative to drain water disposal into the SWMA; and options that include continuing the current practice of drain water disposal into the SWMA. Other options include elements of both of these alternatives. Additional discussion of specific options will follow a brief summary of the technical work supporting our assessment of drainage related issues at the Reservation. 67 refs., 57 figs., 15 tabs.

  6. Performance of a narrow buffer strip in abating agricultural pollutants in the shallow subsurface water flux.

    PubMed

    Borin, Maurizio; Bigon, Elisa; Zanin, Giuseppe; Fava, Luca

    2004-09-01

    The performance of a narrow buffer strip in abating dissolved P, electrical conductivity and herbicides (terbuthylazine, alachlor, nicosulfuron, pendimethalin, linuron) in subsurface water coming from cropland was tested in an experiment carried out on the low plains of the Veneto Region (NE Italy). The experiment lasted from December 1997 to June 1999, monitoring subsurface water quality entering and exiting a buffer composed of a grass strip (5 m wide) and 1 m wide row of trees. Dissolved phosphorus concentrations were reduced by almost 100% passing through the buffer and in most cases exiting water satisfied the limit for avoiding eutrophication. A positive effect was also detected on ECW (reduced by 20%), while pH was not significantly altered. Herbicide concentration abatement varied between 60 and 90%, depending on the chemical and the time elapsed since application.

  7. Benthic invertebrates of benchmark streams in agricultural areas of eastern Wisconsin, Western Lake Michigan Drainages

    USGS Publications Warehouse

    Rheaume, S.J.; Lenz, B.N.; Scudder, B.C.

    1996-01-01

    Information gathered from these benchmark streams can be used as a regional reference for comparison with other streams in agricultural areas, based on communities of aquatic biota, habitat, and water quality.

  8. Nutrient removal of agricultural drainage water using algal turf scrubbers and solar power

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Restoration of the Chesapeake Bay poses significant challenges because of increasing population pressure, conversion of farmland to urban/suburban development, and the expense of infrastructure needed to achieve significant and sustained nutrient reductions from agricultural and urban sources. One ...

  9. Modeling leakage pathways in subsurface formations. Fluid drainage through multiple fractures in porous media: Insights from Hele Shaw cell experiments

    NASA Astrophysics Data System (ADS)

    Ray, Sujata

    2017-04-01

    interface between the newly introduced dye and the ambient fluid in the cell. These shapes were found to be different in a cell placed horizontally versus one placed on an incline, suggesting that the geometry and flow conditions in a formation affecting the transport of an injected fluid. These findings may be used as a basis for predicting behavior of a fluid injected into a fractured formation in the subsurface.

  10. Laboratory Testing of Foundry Sands as Bulking Agents for Porous Media Filters Used to Treat Agricultural Drainage Waters

    NASA Astrophysics Data System (ADS)

    Allred, B. J.

    2008-12-01

    Foundry sands are industrial byproducts that may have potential application as bulking agents that when mixed with small amounts of more chemically reactive materials (i.e. sulfur modified iron, fly ash, etc.) can be used to produce porous media filters capable of removing contaminants from agricultural drainage waters. Foundry sand bulking agents are attractive primarily as a low cost means to maintain the hydraulic efficiency of a filter. Secondarily, the foundry sands themselves may have some capacity for removal of agricultural nutrients and pesticides from water. Consequently, a laboratory study was initiated to quantify hydraulic efficiency and agricultural contaminant removal abilities of six foundry sands. Of the six foundry sands tested, all were obtained in central Ohio, three from iron casting foundries, two from steel casting foundries, and one from an aluminum casting foundry. Hydraulic efficiencies of the foundry sands were assessed by measuring hydraulic conductivity with twice replicated falling-head permeability tests. Batch tests were employed to evaluate foundry sand potential to treat water containing nitrate and phosphate nutrients, along with the pesticide, atrazine. Five of the six foundry sand samples had measured hydraulic conductivity values from 7.6 x 10-3 cm/s to 3.8 x 10-2 cm/s, which is in the range of hydraulic conductivity values found for clean sand. The one foundry sand that was an exception had much lower measured hydraulic conductivity values of 2.75 x 10-5 cm/s and 5.76 x 10-5 cm/s. For the batch tests conducted, none of the nitrate was removed by any of the six foundry sands; however, conversely, almost all of the phosphate was removed by each foundry sand. Batch test atrazine removal results were much more varied. Compared with baseline batch tests, one foundry sand removed two thirds of the atrazine, one foundry sand removed about one half of the atrazine, three foundry sands removed about a third of the atrazine, and one

  11. Nutrient content at the sediment-water interface of tile-fed agricultural drainage ditches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extensive network of tile drains present in the Midwest USA accelerate losses of nutrients to receiving ditches, rivers and eventually to the Gulf of Mexico. Nutrient inputs from agricultural watersheds and their role in affecting water quality have received increased attention recently; however, be...

  12. (226) RA AND (228) RA ACTIVITIES ASSOCIATED WITH AGRICULTURAL DRAINAGE PONDS AND WETLAND PONDS IN THE KANKAKEE WATERSHED, IL-IN, USA

    EPA Science Inventory

    Background radioactivity is elevated in many agricultural drainage ponds and also constructed wetland ponds in the Kankakee watershed. During 1995-1999, gross-a and -B activities were measured up to 455 and 1650 mBq L-1, respectively. 226Ra and 228Ra averaged 139 and 192 mBq L-01...

  13. Toxicity of agricultural subsurface drainwater from the San Joaquin Valley, California to juvenile chinook salmon and striped bass

    USGS Publications Warehouse

    Saiki, Michael K.; Jennings, Mark R.; Wiedmeyer, Raymond H.

    1992-01-01

    Juvenile chinook salmon Oncorhynchus tshawytscha (40-50 mm total length, TL) and striped bass Morone saxatilis (30-40 mm TL) were exposed to serial dilutions (100, 50, 25, and 12.5%) of agricultural subsurface drainwater (WWD), reconstituted drainwater (RWWD), and reconstituted seawater (IO). Agricultural subsurface drainwater contained naturally elevated concentrations of major ions (such as sodium and sulfate) and trace elements (especially boron and selenium), RWWD contained concentrations of major ions that mimicked those in WWD but trace elements were not elevated, and IO contained concentrations of total dissolved salt that were similar to those in WWD and RWWD but chloride replaced sulfate as the dominant anion. After 28 d of static exposure, over 75% of the chinook salmon in 100% WWD had died, whereas none had died in other dilutions and water types. Growth of chinook salmon in WWD and RWWD, but not in IO, exhibited dilution responses. All striped bass died in 100% WWD within 23 d, whereas 19 of 20 striped bass had died in 100% RWWD after 28 d. In contrast, none died in 100% IO. Growth of striped bass was impaired only in WWD. Fish in WWD accumulated as much as 200 μg/g (dry-weight basis) of boron, whereas fish in control water accumulated less than 3.1 μg/g. Although potentially toxic concentrations of selenium occurred in WWD (geometric means, 158-218 μg/L), chinook salmon and striped bass exposed to this water type accumulated 5.7 μg Se/g or less. These findings indicate that WWD was toxic to chinook salmon and striped bass. Judging from available data, the toxicity of WWD was due primarily to high concentrations of major ions present in atypical ratios, to high concentrations of sulfate, or to both. High concentrations of boron and selenium also may have contributed to the toxicity of WWD, but their effects were not clearly delineated.

  14. Hydraulic flow characteristics of agricultural residues for denitrifying bioreactor media

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Denitrifying bioreactors are a promising technology to mitigate agricultural subsurface drainage nitrate-nitrogen losses, a critical water quality goal for the Upper Mississippi River Basin. This study was conducted to evaluate the hydraulic properties of agricultural residues that are potential bio...

  15. Determination of sulfadiazine in phosphate- and DOC-rich agricultural drainage water using solid-phase extraction followed by liquid chromatography-tandem mass spectrometry.

    PubMed

    Bouyou, P A Léon; Weisser, Johan J; Strobel, Bjarne W

    2014-08-01

    Trace levels of the veterinary antibiotic compound sulfadiazine (SDZ) can be determined in agricultural drainage water samples with this new method. Optimized sample pretreatment and solid-phase extraction was combined with liquid chromatography coupled to tandem mass spectrometry (SPE LC-MS/MS) using positive electrospray ionization. The linear dynamic range for the LC-MS/MS was assessed from 5 μg/L to 25 mg/L with a 15-point calibration curve displaying a coefficient of correlation r(2) = 0.9915. Agricultural drainage water spiked at a concentration of 25 ng/L gave recoveries between 63 and 98 % (relative standard deviation 15 %), while at 10 ng/L, it showed a lower recovery of 32 % (relative standard deviation 47 %). The final SPE LC-MS/MS method had a limit of detection (LOD)(Method) and a limit of quantification (LOQ)(Method) of 7.5 and 23 ng/L agricultural drainage water, respectively. Determination of SDZ, spiked at a realistic concentration of 50 μg/L, in artificial drainage water (ADW) containing common and high levels of phosphate (0.05, 0.5, and 5 mg/L) gave recoveries between 70 and 92 % (relative standard deviation 7.4-12.9 %). Analysis of the same realistic concentration of SDZ in ADW, spiked with common and high levels of dissolved organic carbon (2, 6, and 15 mg/L) confirmed the possible adaptation of a tandem solid-phase extraction (strong anion exchange (SAX)-hydrophilic-lipophilic balance (HLB)) followed by liquid chromatography-tandem mass spectrometry methodology. Recoveries obtained ranged from 104 to 109 % (relative standard deviation 2.8-5.2 %). The new methods enable determination of the veterinary antibiotic compound SDZ in agricultural drainage water from field experiments and monitoring schemes for phosphate- and dissolved organic carbon (DOC)-rich water samples in intensive farming areas.

  16. Contaminant exposure of willets feeding in agricultural drainages of the Lower Rio Grande Valley of South Texas.

    PubMed

    Custer, T W; Mitchell, C A

    1991-02-01

    Willets (Catoptrophorus semipalmatus) were collected in June and August 1986 at the outlets of two agricultural drainages into the Lower Laguna Madre of South Texas and at two other Texas coastal sites. Mean liver concentration of arsenic was higher in August than June. Over 20% of the livers had arsenic concentrations elevated above a suggested background level of 5.0 ppm dry weight (DW), but concentrations (maximum 15 ppm) were below those associated with acute toxicity. Selenium concentration in livers varied from 2.3 to 8.3 ppm DW for all locations and represented background levels. Mercury concentrations in livers for all locations (means = 2.0 to 3.4, maximum 17 ppm DW) were below those associated with avian mortality and similar to levels found in other estuarine/marine birds. DDE in carcasses was higher in adults (mean = 1.0 ppm wet weight) than juveniles (0.2 ppm), and higher in August (1.0 ppm) than June (0.5 ppm); however, DDE concentrations were generally at background levels. Based on brain cholinesterase activity, willets were not recently exposed to organophosphate pesticides.

  17. Use of vegetated agricultural drainage ditches to decrease toxicity of irrigation runoff from tomato and alfalfa fields in California, USA.

    PubMed

    Werner, Inge; Deanovic, Linda A; Miller, Jeff; Denton, Debra L; Crane, David; Mekebri, Abdou; Moore, Matthew T; Wrysinski, Jeanette

    2010-12-01

    The current study investigated the potential of vegetated drainage ditches for mitigating the impact of agricultural irrigation runoff on downstream aquatic ecosystems. Water column toxicity to larval fathead minnow (Pimephales promelas),and the amphipod Hyalella azteca was measured for 12 h or less at the ditch inflow and outflow, using custom-built in situ exposure systems. In addition, water and sediment samples were subject to standard toxicity tests with Ceriodaphnia dubia and H. azteca, respectively. No acute toxicity to larval fathead minnow was observed; however, runoff was highly toxic to invertebrates. Passage through a 389- to 402-m section of vegetated ditch had a mitigating effect and reduced toxicity to some degree. However, runoff from an alfalfa field treated with chlorpyrifos remained highly toxic to both invertebrate species, and runoff from a tomato field treated with permethrin remained highly toxic to H. azteca after passage through the ditch. Predicted toxic units calculated from insecticide concentrations in runoff and 96-h median lethal concentration (LC50) values generally agreed with C. dubia toxicity measured in the laboratory but significantly underestimated in situ toxicity to H. azteca. Sediments collected near the ditch outflow were toxic to H. azteca. Results from the current study demonstrate that experimental vegetated ditches were unable to eliminate the risk of irrigation runoff to aquatic ecosystems. In addition, protective measures based on chemical concentrations or laboratory toxicity tests with C. dubia do not ensure adequate protection of aquatic ecosystems from pyrethroid-associated toxicity.

  18. Contaminant exposure of willets feeding in agricultural drainages of the lower Rio Grande valley of south Texas

    USGS Publications Warehouse

    Custer, T.W.; Mitchell, C.A.

    1991-01-01

    Willets (Catoptrophorus semipalmatus) were collected in June and August 1986 at the outlets of two agricultural drainages into the Lower Laguna Madre of South Texas and at two other Texas coastal sites. Mean liver concentration of arsenic was higher in August than June. Over 20% of the livers had arsenic concentrations elevated above a suggested background level of 5.0 ppm dry weight (DW), but concentrations (maximum 15 ppm) were below those associated with acute toxicity. Selenium concentration in livers varied from 2.3 to 8.3 ppm DW for all locations and represented background levels. Mercury concentrations in livers for all locations (means = 2.0 to 3.4, maximum 17 ppm DW) were below those associated with avian mortality and similar to levels found in other estuarine/marine birds. DDE in carcasses was higher in adults (mean = 1.0 ppm wet weight) than juveniles (0.2 ppm), and higher in August (1.0 ppm) than June (0.5 ppm); however, DDE concentrations were generally at background levels. Based on brain cholinesterase activity, willets were not recently exposed to organophosphate pesticides.

  19. Agricultural pesticide applications and observed concentrations in surface waters from four drainage basins in the Central Columbia Plateau, Washington and Idaho, 1993-94

    USGS Publications Warehouse

    Wagner, R.J.; Ebbert, J.C.; Roberts, L.M.; Ryker, S.J.

    1995-01-01

    As part of the U.S. Geological Survey's National Water-Quality Assessment Program, the use and occurrence of agricultural pesticides were investigated in four drainage basins--two dominated by irrigated agriculture and two by dryland agriculture--in the Central Columbia Plateau of eastern Washington. For this study, 85 pesticides or pesticide metabolites were selected for analysis from a list of nearly 400 compounds commonly used in the United States. Pesticide-use data included estimates of the total quantity of herbicides, insecticides, and fungicides applied to croplands in each of the four drainage basins and reported times of application for selected pesticides. Pesticide-occurrence data included concentrations of pesticides in samples collected at one surface-water site at or near the outflow of each of the four drainage basins, where surface waters were sampled one to five times a month from March 1993 through May 1994. Of the 85 pesticides or pesticide metabolites targeted for analysis, a total of 45 different compounds were detected in samples from the four sites, ranging in concentration from at or near the limit of detection (as low as 0.001 microgram per liter) to a maximum of 8.1 micrograms per liter. None of the concentrations of pesticides exceeded the U.S. Environmental Protection Agency (USEPA) drinking water standards, but concentrations of five pesticides exceeded the USEPA freshwater-chronic criteria for the protection of aquatic life. Forty-one different pesticides or pesticide metabolites were detected in surface waters sampled at the two sites representing irrigated agriculture drainage basins. The herbicides atrazine, DCPA, and EPTC were detected most frequently at the two sampling sites. Not all pesticides that were applied were detected, however. For example, disulfoton, phorate, and methyl parathion accounted for 15 percent of the insecticides applied in the two irrigated drainage basins, yet none of these pesticides were detected in

  20. Cost-Effectiveness Analysis of Surface Flow Constructed Wetlands (SFCW) for Nutrient Reduction in Drainage Discharge from Agricultural Fields in Denmark

    NASA Astrophysics Data System (ADS)

    Gachango, F. G.; Pedersen, S. M.; Kjaergaard, C.

    2015-12-01

    Constructed wetlands have been proposed as cost-effective and more targeted technologies in the reduction of nitrogen and phosphorous water pollution in drainage losses from agricultural fields in Denmark. Using two pig farms and one dairy farm situated in a pumped lowland catchment as case studies, this paper explores the feasibility of implementing surface flow constructed wetlands (SFCW) based on their cost effectiveness. Sensitivity analysis is conducted by varying the cost elements of the wetlands in order to establish the most cost-effective scenario and a comparison with the existing nutrients reduction measures carried out. The analyses show that the cost effectiveness of the SFCW is higher in the drainage catchments with higher nutrient loads. The range of the cost effectiveness ratio on nitrogen reduction differs distinctively with that of catch crop measure. The study concludes that SFCW could be a better optimal nutrients reduction measure in drainage catchments characterized with higher nutrient loads.

  1. Cost-Effectiveness Analysis of Surface Flow Constructed Wetlands (SFCW) for Nutrient Reduction in Drainage Discharge from Agricultural Fields in Denmark.

    PubMed

    Gachango, F G; Pedersen, S M; Kjaergaard, C

    2015-12-01

    Constructed wetlands have been proposed as cost-effective and more targeted technologies in the reduction of nitrogen and phosphorous water pollution in drainage losses from agricultural fields in Denmark. Using two pig farms and one dairy farm situated in a pumped lowland catchment as case studies, this paper explores the feasibility of implementing surface flow constructed wetlands (SFCW) based on their cost effectiveness. Sensitivity analysis is conducted by varying the cost elements of the wetlands in order to establish the most cost-effective scenario and a comparison with the existing nutrients reduction measures carried out. The analyses show that the cost effectiveness of the SFCW is higher in the drainage catchments with higher nutrient loads. The range of the cost effectiveness ratio on nitrogen reduction differs distinctively with that of catch crop measure. The study concludes that SFCW could be a better optimal nutrients reduction measure in drainage catchments characterized with higher nutrient loads.

  2. Performance of dentrification beds for removing nitrate from drainage water at cold temperatures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transport of soluble nitrogen and phosphorus to water bodies has been a concern for many years due to human health issues, and is a major contributor to the formation of oxygen deficiency in aquatic ecosystems. Agricultural subsurface drainage is one pathway for transport of excess nutrients to surf...

  3. Analysis of the potential impacts on surface water quality resulting from the proposed use of the San Luis Drain to transport agricultural drainage through the northern Grasslands

    SciTech Connect

    Quinn, N.W.T.

    1992-05-01

    An Environmental Assessment and initial Study for the interim use of a portion of the San Luis Drain for conveyance water through the Grassland Water District and adjacent Grassland areas was conducted. The project proposes the use of 18 miles of the San Luis Drain for the conveyance of agricultural drainage water for a period of five years and the elimination of agricultural drainage discharges from 76 miles of existing channels in and adjacent to the Grassland Water District. A report was prepared to (a) quantify the potential project effects on surface water quality within Salt and Mud Sloughs and the San Joaquin River using currently available data, and (b) to improve the understanding of existing water supply and drainage operations within the Grassland area. After submission of the original report it was brought to the attention of one of the coauthors that the database on selenium and boron concentrations in drainage water did not include the water quality data collected by the Regional Water Quality Control Board (CRWQCB). In addition, the US Bureau of Reclamation (USBR) requested further examination of Grasslands hydrology to estimate the quantity of supplemental water that would be needed to restore the San Joaquin River to the same TDS and trace element concentrations prior to implementation of the project. This report addresses these issues.

  4. Agriculture, irrigation, and drainage on the west side of the San Joaquin Valley, California: Unified perspective on hydrogeology, geochemistry and management

    SciTech Connect

    Narasimhan, T.N.; Quinn, N.W.T.

    1996-03-01

    The purpose of this report is to provide a broad understanding of water-related issues of agriculture and drainage on the west side of the San Joaquin Valley. To this end, an attempt is made to review available literature on land and water resources of the San Joaquin Valley and to generate a process-oriented framework within which the various physical-, chemical-, biological- and economic components of the system and their interactions are placed in mutual perspective.

  5. A simulation-based suitability index of the quality and quantity of agricultural drainage water for reuse in irrigation.

    PubMed

    Allam, Ayman; Fleifle, Amr; Tawfik, Ahmed; Yoshimura, Chihiro; El-Saadi, Aiman

    2015-12-01

    The suitability of agricultural drainage water (ADW) for reuse in irrigation was indexed based on a simulation of quality and quantity. The ADW reuse index (DWRI) has two components; the first one indicates the suitability of water quality (QLT) for reuse in irrigation based on the mixing ratio of ADW to canal irrigation water without violating the standards of using mixed water in irrigation, while the second indicates the available water quantity (QNT) based on the ratio of the available ADW to the required reuse discharge to meet the irrigation requirements alongside the drain. The QLT and QNT values ranged from 0 to ≥3 and from 0 to ≥0.40, respectively. Correspondingly, five classes from excellent to poor and from high scarcity to no scarcity were proposed to classify the QLT and QNT values, respectively. This approach was then applied to the Gharbia drain in the Nile Delta, Egypt, combined with QUAL2Kw simulations in the summer and winter of 2012. The QLT values along the drain ranged from 1.11 to 2.91 and 0.68 to 1.73 for summer and winter, respectively. Correspondingly, the QLT classes ranged from good to very good and from fair to good, respectively. In regard to QNT, values ranged from 0.10 to 0.62 and from 0.10 to 0.88 for summer and winter, respectively. Correspondingly, the QNT classes ranged from medium scarcity to no scarcity for both seasons. The demonstration of DWRI in the Gharbia drain suggests that the proposed index presents a simple tool for spatially evaluating the suitability of ADW for reuse in irrigation.

  6. Airport Pavement Drainage

    DTIC Science & Technology

    1990-06-01

    drainage layer and trench drains can be found in Cedergren (10). 4.2 COMPONENTS OF SUBSURFACE DRAINAGE SYSTEM 4.2.1 Outflow Once the water has found...According to Cedergren (10) the open graded aggregate can replace the normally used dense graded materials on an inch-for-inch basis. A main problem in...the perforated pipe to prevent fines from entering, Figure 4.24 (11). Cedergren (10) suggests that collector pipes should be 42 laid with the

  7. Long-term tillage and drainage influences on greenhouse gas fluxes from a poorly-drained soil of central Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intensive tillage practices and poorly-drained soils of Midwestern USA are the prime reasons for greenhouse gas (GHG) fluxes from agriculture. The naturally poorly-drained soils prevalent in this region require subsurface drainage for improved aeration and improved crop productivity. Soil surface GH...

  8. Method for identifying subsurface fluid migration and drainage pathways in and among oil and gas reservoirs using 3-D and 4-D seismic imaging

    DOEpatents

    Anderson, R.N.; Boulanger, A.; Bagdonas, E.P.; Xu, L.; He, W.

    1996-12-17

    The invention utilizes 3-D and 4-D seismic surveys as a means of deriving information useful in petroleum exploration and reservoir management. The methods use both single seismic surveys (3-D) and multiple seismic surveys separated in time (4-D) of a region of interest to determine large scale migration pathways within sedimentary basins, and fine scale drainage structure and oil-water-gas regions within individual petroleum producing reservoirs. Such structure is identified using pattern recognition tools which define the regions of interest. The 4-D seismic data sets may be used for data completion for large scale structure where time intervals between surveys do not allow for dynamic evolution. The 4-D seismic data sets also may be used to find variations over time of small scale structure within individual reservoirs which may be used to identify petroleum drainage pathways, oil-water-gas regions and, hence, attractive drilling targets. After spatial orientation, and amplitude and frequency matching of the multiple seismic data sets, High Amplitude Event (HAE) regions consistent with the presence of petroleum are identified using seismic attribute analysis. High Amplitude Regions are grown and interconnected to establish plumbing networks on the large scale and reservoir structure on the small scale. Small scale variations over time between seismic surveys within individual reservoirs are identified and used to identify drainage patterns and bypassed petroleum to be recovered. The location of such drainage patterns and bypassed petroleum may be used to site wells. 22 figs.

  9. Method for identifying subsurface fluid migration and drainage pathways in and among oil and gas reservoirs using 3-D and 4-D seismic imaging

    DOEpatents

    Anderson, Roger N.; Boulanger, Albert; Bagdonas, Edward P.; Xu, Liqing; He, Wei

    1996-01-01

    The invention utilizes 3-D and 4-D seismic surveys as a means of deriving information useful in petroleum exploration and reservoir management. The methods use both single seismic surveys (3-D) and multiple seismic surveys separated in time (4-D) of a region of interest to determine large scale migration pathways within sedimentary basins, and fine scale drainage structure and oil-water-gas regions within individual petroleum producing reservoirs. Such structure is identified using pattern recognition tools which define the regions of interest. The 4-D seismic data sets may be used for data completion for large scale structure where time intervals between surveys do not allow for dynamic evolution. The 4-D seismic data sets also may be used to find variations over time of small scale structure within individual reservoirs which may be used to identify petroleum drainage pathways, oil-water-gas regions and, hence, attractive drilling targets. After spatial orientation, and amplitude and frequency matching of the multiple seismic data sets, High Amplitude Event (HAE) regions consistent with the presence of petroleum are identified using seismic attribute analysis. High Amplitude Regions are grown and interconnected to establish plumbing networks on the large scale and reservoir structure on the small scale. Small scale variations over time between seismic surveys within individual reservoirs are identified and used to identify drainage patterns and bypassed petroleum to be recovered. The location of such drainage patterns and bypassed petroleum may be used to site wells.

  10. Hydrologic and water-quality data in selected agricultural drainages in Beaufort and Hyde Counties, North Carolina, 1990-92

    USGS Publications Warehouse

    Treece, M.W.

    1993-01-01

    An investigation was begun in 1988 to: (1) quantify nutrient, sediment, and freshwater loadings in canals that collect drainage from cropland field ditches; (2) determine the effects of tide gates and flashboard risers on these loadings and on receiving water quality; and (3) characterize the effects of drainage on the salinity regime of a tidal creek. Data were collected in three canals in Hyde County, two canals in Beaufort County, and in Campbell Creek, which receives drainage directly from the Beaufort County canals. A tide gate was placed in one of the Hyde County canals near the beginning of the investigation. In August 1990 following more than 2 years of data collection, control structures were placed in the remaining two Hyde County canals. Flashboard risers were installed in the Beaufort County canals in April 1991. Hydrologic and water quality data are presented for each of the study sites for the period of October 1990 through May 1992. Following a description of the study sites and data collection methods, data are presented for the five drainage canals and Campbell Creek. The data collected included: (1) daily values of accumulated precipitation; (2) water level statistics; (3) daily mean values of discharge in the canals; (4) biweekly water quality measurements and sample analyses; (5) storm-event water quality measurements and sample analyses; (6) continuous records of specific conductance in the canals; (7) vertical profiles of salinity in Campbell Creek; and (8) daily mean values of salinity at five sites at Campbell Creek.

  11. The residence time of intensively managed agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Bowling, Laura; Cherkauer, Keith; Chiu, Chun-mei; Rahman, Sanoar

    2015-04-01

    Much of the agricultural landscape across the Midwestern United States is intensively managed through numerous surface and subsurface drainage improvements, and the growing extraction of groundwater resources. The relatively recent glaciation of the North Central region means that the landscape is less dissected and hydrologically connected than older till areas. Low topographic gradients and underlying dense till which restricts vertical water movement, as well as kettle depressions, have led to poorly drained soils and extensive wetlands within the landscape. Large areas of this land could only be farmed once the excess water was removed through artificial surface and subsurface drainage. Conventional wisdom in the region maintains that subsurface tile drainage reduces the occurrence of peak flow events by increasing soil water storage capacity. At the watershed scale, this view does not take into account the coincident increase in surface drainage and reduction in residence time in surface depressions. This paper explores to what degree water management and irrigation has changed surface and subsurface water storage and residence time over the last century and how this has impacted flow duration throughout the Wabash River system in Indiana, USA. The effects of subsurface tile drains, wetlands and aquifer storage are explicitly represented within the Variable Infiltration Capacity (VIC) macroscale hydrology model. We maintain a focus on the entire Wabash River, a river system of historic importance that is also representative of many similar areas in the till plain region of the agricultural Midwest, which contribute to water quality and flood dynamics of the Mississippi river system. By lowering the water table, surface and subsurface drainage improvements have increased the subsurface storage capacity at the beginning of rain events, but this is overwhelmed by the decrease in surface storage capacity for intermediate to large events, decreasing the current

  12. Long-Term Monitoring of Waterborne Pathogens and Microbial Source Tracking Markers in Paired Agricultural Watersheds under Controlled and Conventional Tile Drainage Management

    PubMed Central

    Wilkes, Graham; Brassard, Julie; Edge, Thomas A.; Gannon, Victor; Gottschall, Natalie; Jokinen, Cassandra C.; Jones, Tineke H.; Khan, Izhar U. H.; Marti, Romain; Sunohara, Mark D.; Topp, Edward

    2014-01-01

    Surface waters from paired agricultural watersheds under controlled tile drainage (CTD) and uncontrolled tile drainage (UCTD) were monitored over 7 years in order to determine if there was an effect of CTD (imposed during the growing season) on occurrences and loadings of bacterial and viral pathogens, coliphages, and microbial source tracking markers. There were significantly lower occurrences of human, ruminant, and livestock (ruminant plus pig) Bacteroidales markers in the CTD watershed in relation to the UCTD watershed. As for pathogens, there were significantly lower occurrences of Salmonella spp. and Arcobacter spp. in the CTD watershed. There were no instances where there were significantly higher quantitative loadings of any microbial target in the CTD watershed, except for F-specific DNA (F-DNA) and F-RNA coliphages, perhaps as a result of fecal inputs from a hobby farm independent of the drainage practice treatments. There was lower loading of the ruminant marker in the CTD watershed in relation to the UCTD system, and results were significant at the level P = 0.06. The odds of Salmonella spp. occurring increased when a ruminant marker was present relative to when the ruminant marker was absent, yet for Arcobacter spp., the odds of this pathogen occurring significantly decreased when a ruminant marker was present relative to when the ruminant marker was absent (but increased when a wildlife marker was present relative to when the wildlife marker was absent). Interestingly, the odds of norovirus GII (associated with human and swine) occurring in water increased significantly when a ruminant marker was present relative to when a ruminant marker was absent. Overall, this study suggests that fecal pollution from tile-drained fields to stream could be reduced by CTD utilization. PMID:24727274

  13. Effects of tillage and application rate on atrazine transport to subsurface drainage: Evaluation of RZWQM using a six-year field study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Well-tested agricultural system models can improve our understanding of the water quality effects of management practices under different conditions. The Root Zone Water Quality Model (RZWQM) has been tested under a variety of conditions. However, the current model’s ability to simulate pesticide tr...

  14. Separation of drainage runoff during rainfall-runoff episodes using the stable isotope method and drainage water temperature

    NASA Astrophysics Data System (ADS)

    Zajíček, Antonín; Kvítek, Tomáš; Pomije, Tomáš

    2014-05-01

    is similar. The fast component (or direct runoff) of the drainage runoff is formed by a mixture of pre-event and event water at various ratios, with pre-event water, both subsurface and surface, prevailing especially in winter, getting to the drainage runoff from the melting snow cover by preferential ways. This research was supported by Czech Ministry of Agriculture, grant no. QI111C034.

  15. Fractionation and analysis of veterinary antibiotics and their related degradation products in agricultural soils and drainage waters following swine manure amendment.

    PubMed

    Solliec, Morgan; Roy-Lachapelle, Audrey; Gasser, Marc-Olivier; Coté, Caroline; Généreux, Mylène; Sauvé, Sébastien

    2016-02-01

    The fate of antimicrobial active compound residues in the environment, and especially antibiotics used in swine husbandry are of particular interest for their potential toxicity and contribution to antibiotic resistance. The presence of relatively high concentrations of bioactive compounds has been reported in agricultural areas but few information is available on their degradation products. Veterinary antibiotics reach terrestrial environments through many routes, including application of swine manure to soils. The objectives of this project were first, to develop an analytical method able to quantify and identify veterinary antibiotics and their degradation products in manure, soil and water samples; and second, to study the distribution of these target compounds in soils and drainage waters. A brief evaluation of their potential toxicity in the environment was also made. In order to achieve these objectives, liquid chromatography coupled to high-resolution mass spectrometry was used for its ability to quantify contaminants with sensitivity and selectivity, and its capacity to identify degradation products. Samples of manure, soil and water came from a long-term experimental site where swine manure containing veterinary antibiotics has been applied for many years. In this study, tetracycline antibiotics were found at several hundred μg L(-1) in the swine manure slurry used for fertilization, several hundred of ng L(-1) in drainage waters and several ng g(-1) in soils, while degradation products were sometimes found at concentrations higher than the parent compounds.

  16. Filter Fabrics for Airport Drainage.

    DTIC Science & Technology

    1979-09-01

    Systems for *r- field Pavements," Harry R. Cedergren . d. "Development of Guidelines for the Design of Subsurfac( Drainage Systems for Highway Pavement...Structural 4Sectic s," H. R. Cedergren , J. A. Arman, and K. H. O’Brien. e. Drainage of Highway and Airfield Pavements, Harry R. Cedergren .> Five...by Cedergren (974).5 Additionally, several references were used, particularly those describing experimental anu construction prolects using filter

  17. Agriculture

    EPA Pesticide Factsheets

    The EPA Agriculture Resource Directory offers comprehensive, easy-to-understand information about environmental stewardship on farms and ranches; commonsense, flexible approaches that are both environmentally protective and agriculturally sound.

  18. Site Recommendation Subsurface Layout

    SciTech Connect

    C.L. Linden

    2000-06-28

    The purpose of this analysis is to develop a Subsurface Facility layout that is capable of accommodating the statutory capacity of 70,000 metric tons of uranium (MTU), as well as an option to expand the inventory capacity, if authorized, to 97,000 MTU. The layout configuration also requires a degree of flexibility to accommodate potential changes in site conditions or program requirements. The objective of this analysis is to provide a conceptual design of the Subsurface Facility sufficient to support the development of the Subsurface Facility System Description Document (CRWMS M&O 2000e) and the ''Emplacement Drift System Description Document'' (CRWMS M&O 2000i). As well, this analysis provides input to the Site Recommendation Consideration Report. The scope of this analysis includes: (1) Evaluation of the existing facilities and their integration into the Subsurface Facility design. (2) Identification and incorporation of factors influencing Subsurface Facility design, such as geological constraints, thermal loading, constructibility, subsurface ventilation, drainage control, radiological considerations, and the Test and Evaluation Facilities. (3) Development of a layout showing an available area in the primary area sufficient to support both the waste inventories and individual layouts showing the emplacement area required for 70,000 MTU and, if authorized, 97,000 MTU.

  19. Estimation of Tile Drainage Contribution to Streamflow and Nutrient Export Loads

    NASA Astrophysics Data System (ADS)

    Schilling, K. E.; Arenas Amado, A.; Jones, C. S.; Weber, L. J.

    2015-12-01

    Subsurface drainage is a very common practice in the agricultural U.S. Midwest. It is typically installed in poorly drained soils in order to enhance crop yields. The presence of tile drains creates a route for agrichemicals to travel and therefore negatively impacts stream water quality. This study estimated through end-member analyses the contributions of tile drainage, groundwater, and surface runoff to streamflow at the watershed scale based on continuously monitored data. Especial attention was devoted to quantifying tile drainage impact on watershed streamflow and nutrient export loads. Data analyzed includes streamflow, rainfall, soil moisture, shallow groundwater levels, in-stream nitrate+nitrite concentrations and specific conductance. Data were collected at a HUC12 watershed located in Northeast Iowa, USA. Approximately 60% of the total watershed area is devoted to agricultural activities and forest and grassland are the other two predominant land uses. Results show that approximately 20% of total annual streamflow comes from tile drainage and during rainfall events tile drainage contribution can go up to 30%. Furthermore, for most of the analyzed rainfall events groundwater responded faster and in a more dramatic fashion than tile drainage. The State of Iowa is currently carrying out a plan to reduce nutrients in Iowa waters and the Gulf of Mexico (Iowa Nutrient Reduction Strategy). The outcome of this investigation has the potential to assist in Best Management Practice (BMP) scenario selection and therefore help the state achieve water quality goals.

  20. Effects of water-control structures on hydrologic and water-quality characteristics in selected agricultural drainage canals in eastern North Carolina

    USGS Publications Warehouse

    Treece, M.W.; Jaynes, M.L.

    1994-01-01

    large increase of specific conductance in the tidal creek. Flashboard risers had no significant effect on concentrations of dissolved oxygen, suspended sediment, total ammonia plus organic nitrogen, or phosphorus. Maximum concentrations of ammonia nitrogen were smaller at both test sites after riser installation. In addition, concentrations of nitrite plus nitrate nitrogen exceeding 1.0 milligram per liter rarely occurred at the flashboard-riser test sites following installation of the risers. Median loadings of nitrite plus nitrate nitrogen and total nitrogen decreased at one riser test site following flashboard-riser installation. Tide gates and flashboard risers were associated with reductions in concentrations and export of nitrite plus nitrate nitrogen; however, these changes should be interpreted cautiously because reductions were not observed consistently at every site. The hydrology and baseline water-quality characteristics of the two study areas differ, making comparisons of the effectiveness of the two types of water-control structures difficult to interpret. The effects of water-control structures on the hydrology of the drainage canals are more meaningful than the changes in water quality. Tide gates and flashboard risers altered the hydrologic characteristics of the drainage canals and created an environment favorable for nutrient loss or transformation. Both structures retained agricultural drainage upstream, which increased potential storage for infiltration and reduced the potential for surface runoff, sediment, and nutrient transport, and higher peak outflow rates.

  1. Occurrence, distribution, and transport of pesticides in agricultural irrigation-return flow from four drainage basins in the Columbia Basin Project, Washington, 2002-04, and comparison with historical data

    USGS Publications Warehouse

    Wagner, Richard J.; Frans, Lonna M.; Huffman, Raegan L.

    2006-01-01

    Water-quality samples were collected from sites in four irrigation return-flow drainage basins in the Columbia Basin Project from July 2002 through October 2004. Ten samples were collected throughout the irrigation season (generally April through October) and two samples were collected during the non-irrigation season. Samples were analyzed for temperature, pH, specific conductance, dissolved oxygen, major ions, trace elements, nutrients, and a suite of 107 pesticides and pesticide metabolites (pesticide transformation products) and to document the occurrence, distribution, and pesticides transport and pesticide metabolites. The four drainage basins vary in size from 19 to 710 square miles. Percentage of agricultural cropland ranges from about 35 percent in Crab Creek drainage basin to a maximum of 75 percent in Lind Coulee drainage basin. More than 95 percent of cropland in Red Rock Coulee, Crab Creek, and Sand Hollow drainage basins is irrigated, whereas only 30 percent of cropland in Lind Coulee is irrigated. Forty-two pesticides and five metabolites were detected in samples from the four irrigation return-flow drainage basins. The most compounds detected were in samples from Sand Hollow with 37, followed by Lind Coulee with 33, Red Rock Coulee with 30, and Crab Creek with 28. Herbicides were the most frequently detected pesticides, followed by insecticides, metabolites, and fungicides. Atrazine, bentazon, diuron, and 2,4-D were the most frequently detected herbicides and chlorpyrifos and azinphos-methyl were the most frequently detected insecticides. A statistical comparison of pesticide concentrations in surface-water samples collected in the mid-1990s at Crab Creek and Sand Hollow with those collected in this study showed a statistically significant increase in concentrations for diuron and a statistically significant decrease for ethoprophos and atrazine in Crab Creek. Statistically significant increases were in concentrations of bromacil, diuron, and

  2. Foam drainage

    SciTech Connect

    Kraynik, A.M.

    1983-11-01

    Transient drainage from a column of persistent foam has been analyzed theoretically. Gravity-driven flow was assumed to occur through an interconnected network of Plateau borders that define the edges of foam cells taken to be regular pentagonal dodecahedrons. A small liquid volume fraction and monodisperse cell size distribution were assumed. In the basic model, it is assumed that all liquid is contained in Plateau borders that are bounded by rigid gas-liquid interfaces. The predicted half life, the time required for one half of the liquid to drain from the foam, is inversely proportional to the square of the cell diameter, illustrating the importance of foam structure in drainage. Liquid hold up in the films separating adjacent cells, nonuniform initial liquid volume fraction distribution and interfacial mobility are explored. Border suction due to reduced pressure in the Plateau borders provides a mechanism for film drainage. Simultaneous film drainage and flow through the Plateau borders are analyzed. Sufficient conditions for neglecting film drainage kinetics are obtained. The results indicate that improved foam stability is related to small cells, liquid hold up in the films and slow film drainage kinetics.

  3. Drainage discharge impacts on hydrology and water quality of receiving streams in the wheatbelt of Western Australia.

    PubMed

    Ali, Riasat; Silberstein, Richard; Byrne, John; Hodgson, Geoff

    2013-11-01

    The use of surface and subsurface drainage to manage waterlogging and salinity in dryland (rainfed) and irrigated agricultural systems is common throughout the world. The drainage systems often discharge into natural streams. The same is true for the wheatbelt drainage systems in south-western Australia, where 11,000 km (ABS 2003) of artificial drains have been constructed within the last two decades. Prior to this study, the likely impacts of this discharge on the streambed chemistry and water quality of receiving streams were largely unknown. The study evaluated these impacts in creeks receiving the drainage discharge from engineering options in four river systems in south-western Australia. This study clearly showed elevated levels of metals ions, EC and pH in the stream water at treated sites relative to their levels at untreated sites. At most sites, impacts of drainage discharge were observed on the streambed electrical conductivity (EC) and pH (both in 1:5 extract) in the receiving streams; however, there was little evidence of impact on metal ion content in the streambed soil. The study found no clear differences in the dynamics of the watertable adjacent to streams whether they received drainage discharge or not, irrespective of the size of the artificial drainage systems.

  4. Characterizing phosphorus dynamics in tile-drained agricultural fieldsof eastern Wisconsin

    USGS Publications Warehouse

    Madison, Allison; Ruark, Matthew; Stuntebeck, Todd D.; Komiskey, Matthew J.; Good, Laura W; Drummy, Nancy; Cooley, Eric

    2014-01-01

    Artificial subsurface drainage provides an avenue for the rapid transfer of phosphorus (P) from agricultural fields to surface waters. This is of particular interest in eastern Wisconsin, where there is a concentrated population of dairy farms and high clay content soils prone to macropore development. Through collaboration with private landowners, surface and tile drainage was measured and analyzed for dissolved reactive P (DRP) and total P (TP) losses at four field sites in eastern Wisconsin between 2005 and 2009. These sites, which received frequent manure applications, represent a range of crop management practices which include: two chisel plowed corn fields (CP1, CP2), a no-till corn–soybean field (NT), and a grazed pasture (GP). Subsurface drainage was the dominant pathway of water loss at each site accounting for 66–96% of total water discharge. Average annual flow-weighted (FW) TP concentrations were 0.88, 0.57, 0.21, and 1.32 mg L−1 for sites CP1, CP2, NT, and GP, respectively. Low TP concentrations at the NT site were due to tile drain interception of groundwater flow where large volumes of tile drainage water diluted the FW-TP concentrations. Subsurface pathways contributed between 17% and 41% of the TP loss across sites. On a drainage event basis, total drainage explained between 36% and 72% of the event DRP loads across CP1, CP2, and GP; there was no relationship between event drainflow and event DRP load at the NT site. Manure applications did not consistently increase P concentrations in drainflow, but annual FW-P concentrations were greater in years receiving manure applications compared to years without manure application. Based on these field measures, P losses from tile drainage must be integrated into field level P budgets and P loss calculations on heavily manured soils, while also acknowledging the unique drainage patterns observed in eastern Wisconsin.

  5. Characterizing phosphorus dynamics in tile-drained agricultural fields of eastern Wisconsin

    NASA Astrophysics Data System (ADS)

    Madison, Allison M.; Ruark, Matthew D.; Stuntebeck, Todd D.; Komiskey, Matthew J.; Good, Lara W.; Drummy, Nancy; Cooley, Eric T.

    2014-11-01

    Artificial subsurface drainage provides an avenue for the rapid transfer of phosphorus (P) from agricultural fields to surface waters. This is of particular interest in eastern Wisconsin, where there is a concentrated population of dairy farms and high clay content soils prone to macropore development. Through collaboration with private landowners, surface and tile drainage was measured and analyzed for dissolved reactive P (DRP) and total P (TP) losses at four field sites in eastern Wisconsin between 2005 and 2009. These sites, which received frequent manure applications, represent a range of crop management practices which include: two chisel plowed corn fields (CP1, CP2), a no-till corn-soybean field (NT), and a grazed pasture (GP). Subsurface drainage was the dominant pathway of water loss at each site accounting for 66-96% of total water discharge. Average annual flow-weighted (FW) TP concentrations were 0.88, 0.57, 0.21, and 1.32 mg L-1 for sites CP1, CP2, NT, and GP, respectively. Low TP concentrations at the NT site were due to tile drain interception of groundwater flow where large volumes of tile drainage water diluted the FW-TP concentrations. Subsurface pathways contributed between 17% and 41% of the TP loss across sites. On a drainage event basis, total drainage explained between 36% and 72% of the event DRP loads across CP1, CP2, and GP; there was no relationship between event drainflow and event DRP load at the NT site. Manure applications did not consistently increase P concentrations in drainflow, but annual FW-P concentrations were greater in years receiving manure applications compared to years without manure application. Based on these field measures, P losses from tile drainage must be integrated into field level P budgets and P loss calculations on heavily manured soils, while also acknowledging the unique drainage patterns observed in eastern Wisconsin.

  6. Chemical and microbiological water quality of subsurface agricultural drains during a field trial of liquid dairy manure effluent application rate and varying tillage practices, Upper Tiffin Watershed, southeastern Michigan

    USGS Publications Warehouse

    Haack, Sheridan Kidd; Duris, Joseph W.

    2008-01-01

    A field trial was done in the Upper Tiffin River Watershed, in southeastern Michigan, to determine the influence of liquid dairy manure effluent (LDME) management practices on the quality of agricultural subsurface-drain water. Samples from subsurface drains were analyzed for nutrients, fecal-coliform and Escherichia coli (E. coli) bacteria, antibiotics, chemicals typically detected in wastewater, and the occurrence of genes indicating the presence of shiga-toxin-producing E. coli, or of bovine-specific Bacteroidetes bacteria. Samples were collected from November 2, 2006, to March 20, 2007, from eight subsurface drains under field plots that received no LDME and no tillage (controls) or received 4,000 or 8,000 gallons per acre (gal/acre) of LDME and either no tillage or two different types of tillage. The two types of tillage tested were (1) ground-driven, rotary, subsurface cultivation and (2) rolling-tine aeration. Samples were collected before LDME application and at 4 hours, and 1, 2, 6, 7, and 14 days post-application. Nutrient concentrations were high in subsurface-drain water throughout the field-trial period and could not be attributed to the field-trial LDME application. Of the 59 drain-water samples, including those collected before LDME application and control samples for each date, 56 had concentrations greater than the U.S. Environmental Protection Agency (USEPA), Ecoregion VI recommended surface-water criterion for total phosphorus, and all samples had concentrations greater than the recommended total nitrogen criterion. Nitrate + nitrite nitrogen concentration exceeded 20 milligrams per liter for every sample and contributed most to the total nitrogen concentrations. Substantial increases in drain-water concentrations of organic and ammonia nitrogen and total phosphorus were found for all treatments, including controls, at 14 days post-application after 0.84 inch of rainfall over 2 days. E. coli concentrations exceeded the USEPA recreational

  7. Subsurface sounders

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Airborne or spaceborne electromagnetic systems used to detect subsurface features are discussed. Data are given as a function of resistivity of ground material, magnetic permeability of free space, and angular frequency. It was noted that resistivities vary with the water content and temperature.

  8. Reconnecting tile drainage to riparian buffer hydrology for enhanced nitrate removal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riparian buffers are a proven practice for removing NO3 from both overland flow and shallow groundwater. However, in landscapes with artificial subsurface (tile) drainage most of the subsurface flow leaving fields is passed through the buffers in drainage pipes leaving little opportunity for NO3 rem...

  9. Illinois drainage water management demonstration project

    USGS Publications Warehouse

    Pitts, D.J.; Cooke, R.; Terrio, P.J.; ,

    2004-01-01

    Due to naturally high water tables and flat topography, there are approximately 4 million ha (10 million ac) of farmland artificially drained with subsurface (tile) systems in Illinois. Subsurface drainage is practiced to insure trafficable field conditions for farm equipment and to reduce crop stress from excess water within the root zone. Although drainage is essential for economic crop production, there have been some significant environmental costs. Tile drainage systems tend to intercept nutrient (nitrate) rich soil-water and shunt it to surface water. Data from numerous monitoring studies have shown that a significant amount of the total nitrate load in Illinois is being delivered to surface water from tile drainage systems. In Illinois, these drainage systems are typically installed without control mechanisms and allow the soil to drain whenever the water table is above the elevation of the tile outlet. An assessment of water quality in the tile drained areas of Illinois showed that approximately 50 percent of the nitrate load was being delivered through the tile systems during the fallow period when there was no production need for drainage to occur. In 1998, a demonstration project to introduce drainage water management to producers in Illinois was initiated by NRCS4 An initial aspect of the project was to identify producers that were willing to manage their drainage system to create a raised water table during the fallow (November-March) period. Financial assistance from two federal programs was used to assist producers in retrofitting the existing drainage systems with control structures. Growers were also provided guidance on the management of the structures for both water quality and production benefits. Some of the retrofitted systems were monitored to determine the effect of the practice on water quality. This paper provides background on the water quality impacts of tile drainage in Illinois, the status of the demonstration project, preliminary

  10. Projecting the impact of climate change on the effectiveness of Controlled Drainage in the U.S. Corn Belt

    NASA Astrophysics Data System (ADS)

    Lee, C.; Bowling, L. C.; Cherkauer, K. A.

    2015-12-01

    Subsurface tile drainage systems are used to create arable conditions for agriculture in low-gradient regions with poorly drained soils, such as the U.S. Corn Belt. Traditionally these systems allow excess water to continually drain from the landscape until the water table underlying the field drops below the depth of the tile drain. These 'free draining' systems increase the volume of subsurface water, and thus increase the amount of nutrients, leaving fields. Controlled Drainage (CD) is a water conservation practice that allows farmers to decrease the volume of water leaving their field by using a control structure to manually raise the resting water table above the tile drains. In order to better understand the potential impacts of climate change on agricultural drainage in the Corn Belt, this study focuses on evaluating differences in the simulated effectiveness of CD under different climate change scenarios. The Variable Infiltration Capacity (VIC) macroscale hydrology model, with a subsurface drainage algorithm, was calibrated to nine sites across the Midwest with drainflow records from 1987 to 2012. It is used to simulate drainflow from 1980-2010 and 2035-2064 using projections for the A1B, A2 and B1 emissions scenarios from the GFDL, PCM and HadCM3 models to represent variation in the severity of projected climate change. Simulated drainflow volume, timing, and variability for both freely-drained and controlled scenarios is used to quantify projected changes in drainflow and calculate metrics of CD effectiveness in mitigating negative water quality impacts, spatially under different climate scenarios. Assessing potential changes in effectiveness of CD due to climate change is necessary to investigate potential long-term benefits and drawbacks of this best management practice.

  11. Achieving Long-Term Protection of Water Quality of Grand Lake St. Marys Through Implementation of Conservation Practices and Control of Phosphorus Input from Agricultural Drainage

    EPA Science Inventory

    Grand Lake St. Marys (GLSM), a 13,000 acre lake in northwestern Ohio, is experiencing toxic levels of algal blooms resulting primarily from phosphorus input from agricultural runoff. The algal blooms are so severe that the Ohio Department of Natural Resources advised against any...

  12. Effects of exposure to agricultural drainage ditch water on survivorship, distribution, and abundnance of riffle beetles (Coleoptera: Elmidae) in headwater streams of the Cedar Creek watershed, Indiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riffle Beetles (Coleoptera: Elmidae) require very good water quality, mature streams with riffle habitat, and high dissolved oxygen content. As such, they prove to be good indicators of ecological health in agricultural headwater streams. We conducted static renewal aquatic bioassays using water fro...

  13. Effects of Crop Rotation, N Management, Tillage, and Controlled Drainage on nitrate-N Loss in Drain Flow

    NASA Astrophysics Data System (ADS)

    Ma, L.; Malone, R.; Ahuja, L.; Kanwar, R. S.

    2007-12-01

    Accurate simulation of agricultural management effects on N loss in tile drainage is vitally important for understanding hypoxia in the Gulf of Mexico. An experimental study was initiated in 1978 at Nashua, Iowa of the USA to study long-term effects of tillage, crop rotation, and N management practices on subsurface drainage flow and associated N losses. The Root Zone Water Quality Model (RZWQM) was applied to evaluate management effects (tillage, crop rotation, N application, and controlled drainage) on N loss in drain flow. RZWQM simulated the observed increase in N concentration in drain flow with increasing tillage intensity from NT (no-till) to RT (ridge till) to CP (chisel plow) and to MP (moldboard plow). It also adequately simulated tillage effects on yearly drain flow and yearly N loss in drain flow. On the other hand, RZWQM adequately simulated lower yearly drain flow and lower flow-weighted N concentration in drain flow under CS (corn-soybean) and SC (soybean-corn) than under CC (continuous corn). The model also simulated higher N loss from fertilizer-N applications than from manure-N applications. Applying the newly suggested N management practice for the Midwest of controlled drainage, the model simulated a 30% reduction in drain flow and a 29% decrease in N losses in drain flow under controlled drainage (CD) compared to free drainage (FD). With most of the simulations in reasonably close agreement with observations, we concluded that RZWQM is a promising tool for quantifying the relative effects of tillage, crop rotation, N application, and controlled drainage on N loss in drainage flow. Further improvements on simulated management effects on N mineralization and plant N uptake are needed, however.

  14. Monitoring and Modelling of the Long-term Effect of Changing Agriculture on Nitrate Concentrations in Groundwater and Streams in Small Experimental subsurface dominant watersheds

    NASA Astrophysics Data System (ADS)

    Fovet, Ophelie; Hrachowitz, Markus; Ruiz, Laurent; Faucheux, Mikael; Aquilina, Luc; Molenat, Jerome; Durand, Patrick; Gascuel-Odoux, Chantal

    2013-04-01

    Management and prediction of water quality in watersheds is critical especially in agricultural regions. Water quality in watersheds varies in a very broad range of temporal scales, from storm events or diurnal cycles, seasonal cycles, to pluriannual trends. It varies also spatially, with contrasted dynamics of solutes in the soil, the recharge, the groundwater and the streams. This is challenging both in term of monitoring and of modelling. Agricultural watershed are interesting to discriminate short term from long term mechanisms, as most of them experienced drastic changes in agricultural inputs in the past 50 years. Recently, the analysis of long-term stream water quality data sets has allowed improving significantly our understanding of solute residence time in watersheds [1]. However, as historical agricultural practices are usually poorly documented, large assumptions are needed to achieve such exercises. Despite the large amount of research in the past 30 years dedicated to understand and model the dynamics of agricultural-borne diffuse pollution at the watershed level, there is no accepted perceptual model explaining the observed dynamics of water quality simultaneously at all the relevant spatial and temporal scales and a very little number of sites sufficiently documented to test it. We present results from a long-term comprehensive monitoring of agricultural inputs and chemistry of surface water (20 years) and groundwater (10 years) in small experimental watersheds (ORE AgrHys, http://www.inra.fr/ore_agrhys/). Results showed (i) a strong stability in the stream chemistry whereas agricultural inputs in these small watersheds were highly variable from year to year, (ii) a high spatial heterogeneity of the groundwater chemistry, both laterally along the hillslope and vertically and (iii) contrasted behavior of long-term trends in agricultural inputs and nitrate concentration in groundwater. A simple model was developed, based on linear reservoirs, and run

  15. Representing natural and manmade drainage systems in an earth system modeling framework

    SciTech Connect

    Li, Hongyi; Wu, Huan; Huang, Maoyi; Leung, Lai-Yung R.

    2012-08-27

    Drainage systems can be categorized into natural or geomorphological drainage systems, agricultural drainage systems and urban drainage systems. They interact closely among themselves and with climate and human society, particularly under extreme climate and hydrological events such as floods. This editorial articulates the need to holistically understand and model drainage systems in the context of climate change and human influence, and discusses the requirements and examples of feasible approaches to representing natural and manmade drainage systems in an earth system modeling framework.

  16. Homogenization of Spatial Patterns of Hydrologic Response in Artificially Drained Agricultural Catchments

    NASA Astrophysics Data System (ADS)

    Boland, S. J.; Basu, N. B.; Schilling, K.

    2013-12-01

    Anthropogenic modifications to the landscape, with agricultural activities being a primary driver, have resulted in significant alterations to the hydrologic cycle. Artificial drainage, including surface and subsurface drainage (tile drains), is one of the most extensive manipulations in agricultural landscapes and thus is expected to provide a distinct signature of anthropogenic modification. This study adopts a data synthesis approach in an effort to characterize the signature of artificial subsurface drainage. Daily discharge data from 24 basins across the state of Iowa, which encapsulate a range of anthropogenic modifications, are assessed using a variety of flow metrics. Results indicate that the presence of artificial subsurface drainage leads to a homogenization of landscape hydrologic response. Non-tiled watersheds exhibit a decrease in the area-normalized peak discharge and an increase in the baseflow ratio (baseflow/streamflow) with increases in the spatial scale, while scale invariance is apparent in tiled basins. Within-basin variability in hydrograph recession coefficients also appears to decrease with increases in the proportion of the catchment that is artificially drained. Finally, the differences between tiled and non-tiled landscapes disappear at scales greater than approximately 2200 km2, indicating that this may be a threshold scale for studying the effects of tile drainage. This decrease in within-basin variability and the scale invariance of hydrologic metrics in artificially drained watersheds are attributed to the creation of a bypass flow hydrologic pathway that bypasses the complexity of the catchment travel paths. Spatial homogeneity in responses implies that it may be possible to develop more parsimonious hydrologic models for these regions.

  17. A diagnosis of sub-surface water table dynamics in low hydraulic conductivity soils in the sugar cane fields of Pongola, South Africa

    NASA Astrophysics Data System (ADS)

    Malota, Mphatso; Senzanje, Aidan

    2016-04-01

    Water and land are the two natural resources restraining crop production in South Africa. With the increasing demand for food, emphasis has shifted from the sole reliance on rain fed crop production, to irrigation. The deterioration in irrigation water quality from surface water sources is, however, posing a big challenge to the sustainability of irrigated crop production. This is because more water is required for leaching, resulting in shallow water tables in agricultural lands. The installation of well designed subsurface drainage systems alone is not enough; the provision of timely maintenance is also necessary. In this study, the extent and severity of problems as a consequence of shallow water tables and their possible causes were investigated at three sugarcane fields in Pongola, South Africa, having low hydraulic conductivity soils. Also investigated were soil salinity levels and the temporal variation in the salinity of the irrigation water. A water table map of a 32 ha sugarcane field was generated, using observed water table depth (WTD) data from 36 piezometers monitored from September 2011 to February 2012. Out of the total 32 ha under cultivation, 12% was found to be affected by shallow WTDs of less than the 1.0 m design WTD. The inability of natural drainage to cope with subsurface drainage needs and the poor maintenance of subsurface drainage systems contributed to the shallow water tables in the area. Furthermore, the currently adopted drainage design criteria also proved unsatisfactory with mean observed water table depth and drainage discharge (DD) of 20% and 50%, respectively, less than their respective design levels. The salinity of the irrigation water was, on average, 32% higher than threshold tolerance level of sugarcane. The root zone soil salinity levels at the three study sites were greater than the 1.7 dS m-1 threshold for sugar cane. The subsurface drainage design criteria adopted at the site needs to be revisited by ensuring that the

  18. Tile drainage as karst: Conduit flow and diffuse flow in a tile-drained watershed

    USGS Publications Warehouse

    Schilling, K.E.; Helmers, M.

    2008-01-01

    The similarity of tiled-drained watersheds to karst drainage basins can be used to improve understanding of watershed-scale nutrient losses from subsurface tile drainage networks. In this study, short-term variations in discharge and chemistry were examined from a tile outlet collecting subsurface tile flow from a 963 ha agricultural watershed. Study objectives were to apply analytical techniques from karst springs to tile discharge to evaluate water sources and estimate the loads of agricultural pollutants discharged from the tile with conduit, intermediate and diffuse flow regimes. A two-member mixing model using nitrate, chloride and specific conductance was used to distinguish rainwater versus groundwater inputs. Results indicated that groundwater comprised 75% of the discharge for a three-day storm period and rainwater was primarily concentrated during the hydrograph peak. A contrasting pattern of solute concentrations and export loads was observed in tile flow. During base flow periods, tile flow consisted of diffuse flow from groundwater sources and contained elevated levels of nitrate, chloride and specific conductance. During storm events, suspended solids and pollutants adhered to soil surfaces (phosphorus, ammonium and organic nitrogen) were concentrated and discharged during the rapid, conduit flow portion of the hydrograph. During a three-day period, conduit flow occurred for 5.6% of the time but accounted for 16.5% of the total flow. Nitrate and chloride were delivered primarily with diffuse flow (more than 70%), whereas 80-94% of total suspended sediment, phosphorus and ammonium were exported with conduit and intermediate flow regimes. Understanding the water sources contributing to tile drainage and the manner by which pollutant discharge occurs from these systems (conduit, intermediate or diffuse flow) may be useful for designing, implementing and evaluating non-point source reduction strategies in tile-drained landscapes. ?? 2007 Elsevier B.V. All

  19. High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

    SciTech Connect

    Rozemeijer, J. C.; Visser, A.; Borren, W.; Winegram, M.; van der Velde, Y.; Klein, J.; Broers, H. P.

    2016-01-19

    High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. This is achieved by introducing control structures with adjustable overflow levels into subsurface tube drain systems. A small-scale (1 ha) field experiment was designed to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates and the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007–2008) and after (2009–2011). For the N and P concentration measurements, auto-analyzers for continuous records were combined with passive samplers for time-averaged concentrations at individual drain outlets. The experimental setup enabled the quantification of changes in the water and solute balance after introducing controlled drainage. The results showed that introducing controlled drainage reduced the drain discharge and increased the groundwater storage in the field. To achieve this, the overflow levels have to be elevated in early spring, before the drain discharge stops due to dryer conditions and falling groundwater levels. The groundwater storage in the field would have been larger if the water levels in the adjacent ditch were controlled as well by an adjustable weir. The N concentrations and loads increased, which was largely related to elevated concentrations in one of the three monitored tube drains. The P loads via the tube drains reduced due to the reduction in discharge after introducing controlled drainage. Furthermore, this may be counteracted by the higher groundwater levels and the larger contribution of N- and

  20. High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

    NASA Astrophysics Data System (ADS)

    Rozemeijer, J. C.; Visser, A.; Borren, W.; Winegram, M.; van der Velde, Y.; Klein, J.; Broers, H. P.

    2016-01-01

    High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. This is achieved by introducing control structures with adjustable overflow levels into subsurface tube drain systems. A small-scale (1 ha) field experiment was designed to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates and the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007-2008) and after (2009-2011). For the N and P concentration measurements, auto-analyzers for continuous records were combined with passive samplers for time-averaged concentrations at individual drain outlets. The experimental setup enabled the quantification of changes in the water and solute balance after introducing controlled drainage. The results showed that introducing controlled drainage reduced the drain discharge and increased the groundwater storage in the field. To achieve this, the overflow levels have to be elevated in early spring, before the drain discharge stops due to dryer conditions and falling groundwater levels. The groundwater storage in the field would have been larger if the water levels in the adjacent ditch were controlled as well by an adjustable weir. The N concentrations and loads increased, which was largely related to elevated concentrations in one of the three monitored tube drains. The P loads via the tube drains reduced due to the reduction in discharge after introducing controlled drainage. However, this may be counteracted by the higher groundwater levels and the larger contribution of N- and P

  1. High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

    DOE PAGES

    Rozemeijer, J. C.; Visser, A.; Borren, W.; ...

    2016-01-19

    High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. This is achieved by introducing control structures with adjustable overflow levels into subsurface tube drain systems. A small-scale (1 ha) field experiment was designed to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates andmore » the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007–2008) and after (2009–2011). For the N and P concentration measurements, auto-analyzers for continuous records were combined with passive samplers for time-averaged concentrations at individual drain outlets. The experimental setup enabled the quantification of changes in the water and solute balance after introducing controlled drainage. The results showed that introducing controlled drainage reduced the drain discharge and increased the groundwater storage in the field. To achieve this, the overflow levels have to be elevated in early spring, before the drain discharge stops due to dryer conditions and falling groundwater levels. The groundwater storage in the field would have been larger if the water levels in the adjacent ditch were controlled as well by an adjustable weir. The N concentrations and loads increased, which was largely related to elevated concentrations in one of the three monitored tube drains. The P loads via the tube drains reduced due to the reduction in discharge after introducing controlled drainage. Furthermore, this may be counteracted by the higher groundwater levels and the larger contribution

  2. Issues of sustainable irrigated agriculture in the San Joaquin Valley of California in a changing regulatory environment concerning water quality and protection of wildlife

    SciTech Connect

    Quinn, N.W.T.; Delamore, M.L.

    1994-06-01

    Since the discovery of selenium toxicosis in the Kesterson Reservoir in the San Joaquin Valley, California, public perception of irrigated agriculture as a benign competitor for California`s developed water supply has been changed irrevocably. Subsurface return flows from irrigated agriculture were implicated as the source of selenium which led to incidents of reproductive failure in waterfowl and threatened survival of other fish and wildlife species. Stringent water quality objectives were promulgated to protect rivers, tributaries, sloughs and other water bodies receiving agricultural discharges from selenium contamination. Achieving these objectives was left to the agricultural water districts, federal and state agencies responsible for drainage and water quality enforcement in the San Joaquin Basin. This paper describes some of the strategies to improve management of water resources and water quality in response to these new environmental objectives. Similar environmental objectives will likely be adopted by other developed and developing countries with large regions of arid zone agriculture and susceptible wildlife resources. A series of simulation models have been developed over the past four years to evaluate regional drainage management strategies such as: irrigation source control; drainage recycling; selective retirement of agricultural land; regional shallow ground water pumping; coordination of agricultural drainage, wetland and reservoir releases; and short-term ponding of drainage water. A new generation of Geographic Information Service-based software is under development to bridge the gap between planning and program implementation. Use of the decision support system will allow water districts and regulators to continuously monitor drainage discharges to the San Joaquin River in real-time and to assess impacts of management strategies that have been implemented to take advantage of the River`s assimilative capacity for trace elements and salts.

  3. Stormwater Drainage Wells

    EPA Pesticide Factsheets

    Provides information for identifying stormwater drainage wells, learn how to comply with regulations for storm water drainage wells, and how to reduce the threat to ground water from stormwater injection wells.

  4. Urine drainage bags

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000142.htm Urine drainage bags To use the sharing features on this page, please enable JavaScript. Urine drainage bags collect urine. Your bag will attach ...

  5. Transient drainage summary report

    SciTech Connect

    1996-09-01

    This report summarizes the history of transient drainage issues on the Uranium Mill Tailings Remedial Action (UMTRA) Project. It defines and describes the UMTRA Project disposal cell transient drainage process and chronicles UMTRA Project treatment of the transient drainage phenomenon. Section 4.0 includes a conceptual cross section of each UMTRA Project disposal site and summarizes design and construction information, the ground water protection strategy, and the potential for transient drainage.

  6. Hygienic drainage for healthcare.

    PubMed

    Jennings, Peter

    2012-08-01

    Peter Jennings, technical director for ACO Building Drainage, which specialises in the development of corrosion-resistant drainage systems and building products, looks at the key issues to consider when specifying and installing pipework and drainage for hygiene-critical environments such as hospitals and other healthcare facilities.

  7. Drainage effects on stream nitrate-N and hydrology in south-central Minnesota (USA)

    USGS Publications Warehouse

    Magner, J.A.; Payne, G.A.; Steffen, J.

    2004-01-01

    Excessive nitrate-N in south-central Minnesota ditches and streams is related to land-use change, and may be contributing to the development of the zone of hypoxia in the Gulf of Mexico. Intensive land-use (agricultural management) has progressively increased as subsurface drainage has improved crop productivity over the past 25 years. We have examined water at varying scales for ??18O and, nitrate-N concentrations. Additionally, analysis of annual peak flows, and channel geomorphic features provided a measure of hydrologic change. Laboratory and field results indicate that agricultural drainage has influenced riverine source waters, concentrations of nitrate-N, channel dimensions and hydrology in the Blue Earth River (BER) Basin. At the mouth of the BER shallow ground water comprises the largest source water component. The highest nitrate-N concentrations in the BER and tributaries typically occurred in May and June and ranged from 7-34 mg L-1. Peak flows for the 1.01-2-yr recurrence intervals increased by 20-to-206% over the past 25 years. Geomorphic data suggest that small channels (ditches) were entrenched by design, whereas, natural channels incised. Increased frequent peak flows in the BER have created laterally confined channels that are disconnected from an accessible riparian corridor. Frequent access to a functioning riparian zone is important for denitrification.

  8. A synthesis and comparative evaluation of drainage water management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viable large-scale crop production in the United States requires artificial drainage in humid and poorly drained agricultural regions. Excess water removal is generally achieved by installing tile drains that export water to open ditches that eventually flow into streams. Drainage water management...

  9. 7 CFR 1924.108 - Grading and drainage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... fills or extensive earthwork that must support structures and building foundations, these must be... with supporting data sufficient to identify all pertinent subsurface conditions which could adversely affect the structure and show proposed solutions. Grading will promote drainage of surface water...

  10. 7 CFR 1924.108 - Grading and drainage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... fills or extensive earthwork that must support structures and building foundations, these must be... with supporting data sufficient to identify all pertinent subsurface conditions which could adversely affect the structure and show proposed solutions. Grading will promote drainage of surface water...

  11. 7 CFR 1924.108 - Grading and drainage.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... fills or extensive earthwork that must support structures and building foundations, these must be... with supporting data sufficient to identify all pertinent subsurface conditions which could adversely affect the structure and show proposed solutions. Grading will promote drainage of surface water...

  12. 7 CFR 1924.108 - Grading and drainage.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... fills or extensive earthwork that must support structures and building foundations, these must be... with supporting data sufficient to identify all pertinent subsurface conditions which could adversely affect the structure and show proposed solutions. Grading will promote drainage of surface water...

  13. 7 CFR 1924.108 - Grading and drainage.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... fills or extensive earthwork that must support structures and building foundations, these must be... with supporting data sufficient to identify all pertinent subsurface conditions which could adversely affect the structure and show proposed solutions. Grading will promote drainage of surface water...

  14. WATER DRAINAGE MODEL

    SciTech Connect

    J.B. Case

    2000-05-30

    The drainage of water from the emplacement drift is essential for the performance of the EBS. The unsaturated flow properties of the surrounding rock matrix and fractures determine how well the water will be naturally drained. To enhance natural drainage, it may be necessary to introduce engineered drainage features (e.g. drilled holes in the drifts), that will ensure communication of the flow into the fracture system. The purpose of the Water Drainage Model is to quantify and evaluate the capability of the drift to remove water naturally, using the selected conceptual repository design as a basis (CRWMS M&O, 1999d). The analysis will provide input to the Water Distribution and Removal Model of the EBS. The model is intended to be used to provide postclosure analysis of temperatures and drainage from the EBS. It has been determined that drainage from the EBS is a factor important to the postclosure safety case.

  15. Drainage subsidence associated with Arctic permafrost degradation

    NASA Astrophysics Data System (ADS)

    Lewis, K. C.; Zyvoloski, G. A.; Travis, B.; Wilson, C.; Rowland, J.

    2012-12-01

    Arctic sources of greenhouse gas associated with permafrost degradation constitute a large uncertainty in existing climate models. Greenhouse gas release from the Arctic subsurface is mediated by numerous interconnected physical processes; one facet of these is the interplay between surface deformation and melting of subsurface ice. First, we construct analytic solutions describing fluid drainage and soil subsidence subsequent to thawing of a 1-D permafrost column. These solutions lead to formulas giving the total amount of subsidence as well as the time over which subsidence occurs. We give an example application of the analytic model to peat plateau degradation in the Canadian Hudson Bay Lowland and show that the degree of subsidence predicted from our model is consistent with recorded subsidence of peat in western Norway that was drained for cultivation purposes. Second, we numerically model an initially frozen, fluid-saturated, 2-D soil matrix with a thaw zone advancing from the surface downward. With the surface temperature fixed at 5°C, a thaw front propagates to ˜10 m depth within 20 years, and due primarily to drainage of fluid from the pore space, a region of soil depressed by ˜3 m forms above an initially ice-rich subsurface zone. Soil underlying this depressed zone may have its permeability reduced by between 1 and 2 orders of magnitude; this reduction in permeability can act as a negative feedback to thawing.

  16. Martian drainage densities

    USGS Publications Warehouse

    Carr, M.H.; Chuang, F.C.

    1997-01-01

    Drainage densities on Mars range from zero over large areas of volcanic plains to 0.3-0.5 km-1 locally on some volcanoes. These values refer to geologic units, not to drainage basins, as is normal for terrestrial drainage densities. The highest values are close to the lowest terrestrial values derived by similar techniques. Drainage densities were determined for every geologic unit portrayed on the 1:15,000,000 geologic map of Mars. Except for volcanoes the geologic unit with the highest drainage density is the dissected Noachian plains with a drainage density of 0.0074 km-1. The average drainage density for Noachian units is 0.0032 km-1, for Hesperian units is 0.00047 km-1, and for Amazonian units is 0.00007 km-1, excluding the volcanoes. These values are 2-3 orders of magnitude lower than typical terrestrial densities as determined by similar techniques from Landsat images. The low drainage densities, despite a cumulative record that spans billions of years, indicate that compared with the Earth, the channel-forming processes have been very inefficient or have operated only rarely or that the surface is extremely permeable. The high drainage density on volcanoes is attributed to a local cause, such as hydrothermal activity, rather than to a global cause such as climate change. Copyright. Published in 1997 by the American Geophysical Union.

  17. Drainage water management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article introduces a series of papers that report results of field studies to determine the effectiveness of drainage water management (DWM) on conserving drainage water and reducing losses of nitrogen (N) to surface waters. The series is focused on the performance of the DWM (also called contr...

  18. Percutaneous Abscess Drainage

    MedlinePlus

    ... the local anesthetic is injected. Most of the sensation is at the skin incision site which is numbed using local anesthetic. ... open surgical drainage. Risks Any procedure where the skin is penetrated ... organ may be damaged by percutaneous abscess drainage. Occasionally ...

  19. Biotreatment of mine drainage

    SciTech Connect

    Bender, J.; Phillips, R.

    1996-12-31

    Several experiments and field tests of microbial mats are described. One study determined the removal rate of Uranium 238 and metals from groundwater by microbial mats. Free floating mats, immobilized mats, excised mats, and pond treatment were examined. Field tests of acid coal mine drainage and precious metal mine drainage are also summarized. The mechanisms of metal removal are briefly described.

  20. Foam consolidation and drainage.

    PubMed

    Jun, S; Pelot, D D; Yarin, A L

    2012-03-27

    A theoretical model of foam as a consolidating continuum is proposed. The general model is applied to foam in a gravity settler. It is predicted that liquid drainage from foam in a gravity settler begins with a slow drainage stage. Next, a stage with faster drainage occurs where the drainage rate doubles compared to the initial stage. The experiments conducted within the framework of this work confirmed the theoretical predictions and allowed measurements of foam characteristics. Foams of three different concentrations of Pantene Pro-V Classic Care Solutions shampoo were studied, as well as the addition of polyethylene oxide (PEO) in one case. The shampoo's main foaming components are sodium lauryl sulfate and sodium laureth sulfate. It is shown to what extent foam drainage is slowed down by using higher shampoo concentrations and how it is further decreased by adding polymer (PEO).

  1. Drainage Studies Using Pore-Scale Approaches

    NASA Astrophysics Data System (ADS)

    Liu, E. B.; Reed, A. H.; Hilpert, M.

    2007-12-01

    The process of drainage has wide spread applications in soil hydrology, irrigation, and the remediation of contaminants in the subsurface. In this paper, we present the comparison of experimental and pore-scale modeling results for drainage. Using a HD-500 microCT system, X-ray tomographic images (21 micron voxels) of saturation during a drainage experiment were obtained in a porous medium consisting of 20/30 mesh (590- 840 microns) Accusand. Utilizing the segmented microtomographic images of the pore space, we modeled drainage using two pore-scale approaches: (1) the pore-morphology-based simulator (PMBS) developed by Hilpert and Miller (2001), and (2) a Lattice Boltzmann (LB) model. Invasion pathways and pressure-saturation relations obtained from both the PMBS and the LB model were compared with those obtained from experiments. The results of PMBS modeling displayed good agreement with experimental observations, except at high suction and low water saturation values, where both CT resolution and model assumptions become an issue. The LB model is currently being refined, and the results of these simulations will also be presented.

  2. Farm Drainage in the United States. History, Status, and Prospects. Miscellaneous Publication Number 1455.

    ERIC Educational Resources Information Center

    Pavelis, George A., Ed.

    This publication covers the historical, technological, economic, and environmental aspects of agricultural drainage. It draws from the combined knowledge of academic and U.S. Department of Agriculture professionals in public policy, drainage theory, planning, engineering, environmental science, and economics. The main purpose is to review the…

  3. Ear drainage culture

    MedlinePlus

    ... needed. Your health care provider will use a cotton swab to collect the sample from inside the ... Using a cotton swab to take a sample of drainage from the outer ear is not painful. However, ear pain may ...

  4. Influence of tile-drainage on groundwater flow and nitrate transport in heterogeneous geological materials

    NASA Astrophysics Data System (ADS)

    De Schepper, G.; Therrien, R.; Refsgaard, J.

    2012-12-01

    Subsurface drainage is a common agricultural practice in poorly drained production fields to guarantee the productivity of crops and to reduce flooding risks. The impact of shallow tile-drainage networks on groundwater flow patterns and associated nitrate transport from the surface needs to be quantified for adequate agricultural management. A challenge is to represent tile-drain networks in numerical models, at the field scale, while accounting for the influence of subsurface heterogeneities on flow and transport. A numerical model of a tile-drainage system has been developed with the fully integrated HydroGeoSphere model for the Lillebaek agricultural catchment, Denmark. The Lillebaek catchment is an experimental study area where hydraulic heads, stream and drain discharges, as well as groundwater and surface water nitrate concentrations are regularly measured. This catchment includes various tile-drainage networks that are monitored on a daily basis; the one we have been focusing on is about 5 ha within a 34 ha model domain. The Lillebaek catchment subsurface is made of about 30 m thick Quaternary deposits which consist of a local sandy aquifer with upper and lower clayey till units, confining the aquifer in the upper part. The main modelling objective is to assess the influence of tile drains on the water flow pattern within the confining clayey till unit with and on the nitrate reduction zone depth, also known as the redox-interface, while accounting for local geological heterogeneities. Using the national-scale geological model for Denmark combined with available local data, a hydrogeological model at field scale has been generated. A proper representation of the tile-drains geometry is essential to calibrate and validate the water flow model associated with nitrate transport. HydroGeoSphere can represent drains directly into a model as one-dimensional features, which however requires a very fine mesh discretization that limits the size of the simulation

  5. Location and assessment of drainage pipes beneath farm fields and golf course greens using ground penetrating radar: A research summary

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enhancing the efficiency of soil water removal, and in turn crop productivity, on farmland already containing a subsurface drainage system, typically involves installing new drain lines between the old ones. However, before this approach can be attempted, the older drainage pipes need to be located...

  6. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Artificial Drainage (1992) and Irrigation (1997)

    USGS Publications Warehouse

    Wieczorek, Michael; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the estimated area of artifical drainage for the year 1992 and irrigation types for the year 1997 compiled for every MRB_E2RF1 catchment of Major River Basins (MRBs, Crawford and others, 2006). The source data sets were derived from tabular National Resource Inventory (NRI) data sets created by the National Resources Conservation Service (NRCS, U.S. Department of Agriculture, 1995, 2000). Artificial drainage is defined as subsurface drains and ditches. Irrigation types are defined as gravity and pressure. Subsurface drains are described as conduits, such as corrugated plastic tubing, tile, or pipe, installed beneath the ground surface to collect and/or convey drainage. Surface drainage field ditches are described as graded ditches for collecting excess water. Gravity irrigation source is described as irrigation delivered to the farm and/or field by canals or pipelines open to the atmosphere; and water is distributed by the force of gravity down the field by: (1) A surface irrigation system (border, basin, furrow, corrugation, wild flooding, etc.) or (2) Sub-surface irrigation pipelines or ditches. Pressure irrigation source is described as irrigation delivered to the farm and/or field in pump or elevation-induced pressure pipelines, and water is distributed across the field by: (1) Sprinkle irrigation (center pivot, linear move, traveling gun, side roll, hand move, big gun, or fixed set sprinklers), or (2) Micro irrigation (drip emitters, continuous tube bubblers, micro spray or micro sprinklers). NRI data do not include Federal lands and are thus excluded from this dataset. The tabular data for drainage were spatially apportioned to the National Land Cover Dataset (NLCD, Kerie Hitt, U.S. Geological Survey, written commun., 2005) and the tabular data for irrigation were spatially apportioned to an enhanced version of the National Land Cover Dataset (NLCDe, Nakagaki and others, 2007). The MRB_E2RF1 catchments are based on a modified

  7. Electrical Subsurface Grounding Analysis

    SciTech Connect

    J.M. Calle

    2000-11-01

    The purpose and objective of this analysis is to determine the present grounding requirements of the Exploratory Studies Facility (ESF) subsurface electrical system and to verify that the actual grounding system and devices satisfy the requirements.

  8. Subsurface Microbiology and Biogeochemistry

    SciTech Connect

    Fredrickson, Jim K.; Fletcher, Madilyn

    2001-05-01

    Jim contributed a chapter to this book, in addition to co-editing it with Madilyn Fletcher. Fredrickson, J. K., and M. Fletcher. (eds.) 2001 Subsurface Microbiology and Biogeochemistry. Wiley-Liss, Inc., New York.

  9. Ceramic subsurface marker prototypes

    SciTech Connect

    Lukens, C.E.

    1985-05-02

    The client submitted 5 sets of porcelain and stoneware subsurface (radioactive site) marker prototypes (31 markers each set). The following were determined: compressive strength, thermal shock resistance, thermal crazing resistance, alkali resistance, color retention, and chemical resistance.

  10. Effect of Agricultural Practices on Hydrology and Water Chemistry in a Small Irrigated Catchment, Yakima River Basin, Washington

    USGS Publications Warehouse

    McCarthy, Kathleen A.; Johnson, Henry M.

    2009-01-01

    The role of irrigation and artificial drainage in the hydrologic cycle and the transport of solutes in a small agricultural catchment in central Washington's Yakima Valley were explored using hydrologic, chemical, isotopic, age-dating, and mineralogical data from several environmental compartments, including stream water, ground water, overland flow, and streambed pore water. A conceptual understanding of catchment hydrology and solute transport was developed and an inverse end-member mixing analysis was used to further explore the effects of agriculture in this small catchment. The median concentrations of major solutes and nitrates were similar for the single field site and for the catchment outflow site, indicating that the net effects of transport processes for these constituents were similar at both scales. However, concentrations of nutrients were different at the two sites, suggesting that field-scale variations in agricultural practices as well as nearstream and instream biochemical processes are important components of agricultural chemical transformation and transport in this catchment. This work indicates that irrigation coupled with artificial drainage networks may exacerbate the ecological effects of agricultural runoff by increasing direct connectivity between fields and streams and minimizing potentially mitigating effects (denitrification and dilution, for example) of longer subsurface pathways.

  11. Deep subsurface microbial processes

    USGS Publications Warehouse

    Lovley, D.R.; Chapelle, F.H.

    1995-01-01

    Information on the microbiology of the deep subsurface is necessary in order to understand the factors controlling the rate and extent of the microbially catalyzed redox reactions that influence the geophysical properties of these environments. Furthermore, there is an increasing threat that deep aquifers, an important drinking water resource, may be contaminated by man's activities, and there is a need to predict the extent to which microbial activity may remediate such contamination. Metabolically active microorganisms can be recovered from a diversity of deep subsurface environments. The available evidence suggests that these microorganisms are responsible for catalyzing the oxidation of organic matter coupled to a variety of electron acceptors just as microorganisms do in surface sediments, but at much slower rates. The technical difficulties in aseptically sampling deep subsurface sediments and the fact that microbial processes in laboratory incubations of deep subsurface material often do not mimic in situ processes frequently necessitate that microbial activity in the deep subsurface be inferred through nonmicrobiological analyses of ground water. These approaches include measurements of dissolved H2, which can predict the predominant microbially catalyzed redox reactions in aquifers, as well as geochemical and groundwater flow modeling, which can be used to estimate the rates of microbial processes. Microorganisms recovered from the deep subsurface have the potential to affect the fate of toxic organics and inorganic contaminants in groundwater. Microbial activity also greatly influences 1 the chemistry of many pristine groundwaters and contributes to such phenomena as porosity development in carbonate aquifers, accumulation of undesirably high concentrations of dissolved iron, and production of methane and hydrogen sulfide. Although the last decade has seen a dramatic increase in interest in deep subsurface microbiology, in comparison with the study of

  12. Sustainability of irrigated agriculture in the San Joaquin Valley, California.

    PubMed

    Schoups, Gerrit; Hopmans, Jan W; Young, Chuck A; Vrugt, Jasper A; Wallender, Wesley W; Tanji, Ken K; Panday, Sorab

    2005-10-25

    The sustainability of irrigated agriculture in many arid and semiarid areas of the world is at risk because of a combination of several interrelated factors, including lack of fresh water, lack of drainage, the presence of high water tables, and salinization of soil and groundwater resources. Nowhere in the United States are these issues more apparent than in the San Joaquin Valley of California. A solid understanding of salinization processes at regional spatial and decadal time scales is required to evaluate the sustainability of irrigated agriculture. A hydro-salinity model was developed to integrate subsurface hydrology with reactive salt transport for a 1,400-km(2) study area in the San Joaquin Valley. The model was used to reconstruct historical changes in salt storage by irrigated agriculture over the past 60 years. We show that patterns in soil and groundwater salinity were caused by spatial variations in soil hydrology, the change from local groundwater to snowmelt water as the main irrigation water supply, and by occasional droughts. Gypsum dissolution was a critical component of the regional salt balance. Although results show that the total salt input and output were about equal for the past 20 years, the model also predicts salinization of the deeper aquifers, thereby questioning the sustainability of irrigated agriculture.

  13. Guidelines for Design, Construction, and Evaluation of Airport Pavement Drainage

    DTIC Science & Technology

    1990-10-01

    Cedergren et. al. (11) have indicated that subsurface drainage may not be needed in pavement systems where the average annual precipitation is less...contributes water flow to each crack or joint (2). These are several ways in which the surface infiltration rate can be determined. Cedergren (3,4) has...Calculation Modules The program performs the following calculations: 5.5.7.1 Water Sources Surface infiltration (user selectable) Ridgeway procedure Cedergren

  14. Drainage networks after wildfire

    USGS Publications Warehouse

    Kinner, D.A.; Moody, J.A.

    2005-01-01

    Predicting runoff and erosion from watersheds burned by wildfires requires an understanding of the three-dimensional structure of both hillslope and channel drainage networks. We investigate the small-and large-scale structures of drainage networks using field studies and computer analysis of 30-m digital elevation model. Topologic variables were derived from a composite 30-m DEM, which included 14 order 6 watersheds within the Pikes Peak batholith. Both topologic and hydraulic variables were measured in the field in two smaller burned watersheds (3.7 and 7.0 hectares) located within one of the order 6 watersheds burned by the 1996 Buffalo Creek Fire in Central Colorado. Horton ratios of topologic variables (stream number, drainage area, stream length, and stream slope) for small-scale and large-scale watersheds are shown to scale geometrically with stream order (i.e., to be scale invariant). However, the ratios derived for the large-scale drainage networks could not be used to predict the rill and gully drainage network structure. Hydraulic variables (width, depth, cross-sectional area, and bed roughness) for small-scale drainage networks were found to be scale invariant across 3 to 4 stream orders. The relation between hydraulic radius and cross-sectional area is similar for rills and gullies, suggesting that their geometry can be treated similarly in hydraulic modeling. Additionally, the rills and gullies have relatively small width-to-depth ratios, implying sidewall friction may be important to the erosion and evolutionary process relative to main stem channels.

  15. Subsurface Contamination Control

    SciTech Connect

    Y. Yuan

    2001-12-12

    There are two objectives of this report, ''Subsurface Contamination Control''. The first is to provide a technical basis for recommending limiting radioactive contamination levels (LRCL) on the external surfaces of waste packages (WP) for acceptance into the subsurface repository. The second is to provide an evaluation of the magnitude of potential releases from a defective WP and the detectability of the released contents. The technical basis for deriving LRCL has been established in ''Retrieval Equipment and Strategy for Wp on Pallet'' (CRWMS M and O 2000g, 6.3.1). This report updates the derivation by incorporating the latest design information of the subsurface repository for site recommendation. The derived LRCL on the external surface of WPs, therefore, supercede that described in CRWMS M and O 2000g. The derived LRCL represent the average concentrations of contamination on the external surfaces of each WP that must not be exceeded before the WP is to be transported to the subsurface facility for emplacement. The evaluation of potential releases is necessary to control the potential contamination of the subsurface repository and to detect prematurely failed WPs. The detection of failed WPs is required in order to provide reasonable assurance that the integrity of each WP is intact prior to MGR closure. An emplaced WP may become breached due to manufacturing defects or improper weld combined with failure to detect the defect, by corrosion, or by mechanical penetration due to accidents or rockfall conditions. The breached WP may release its gaseous and volatile radionuclide content to the subsurface environment and result in contaminating the subsurface facility. The scope of this analysis is limited to radioactive contaminants resulting from breached WPs during the preclosure period of the subsurface repository. This report: (1) documents a method for deriving LRCL on the external surfaces of WP for acceptance into the subsurface repository; (2) provides a

  16. Subsurface Contamination Control

    SciTech Connect

    Y. Yuan

    2001-11-16

    There are two objectives of this report, ''Subsurface Contamination Control''. The first is to provide a technical basis for recommending limiting radioactive contamination levels (LRCL) on the external surfaces of waste packages (WP) for acceptance into the subsurface repository. The second is to provide an evaluation of the magnitude of potential releases from a defective WP and the detectability of the released contents. The technical basis for deriving LRCL has been established in ''Retrieval Equipment and Strategy for Wp on Pallet'' (CRWMS M and O 2000g, 6.3.1). This report updates the derivation by incorporating the latest design information of the subsurface repository for site recommendation. The derived LRCL on the external surface of WPs, therefore, supercede that described in CRWMS M and O 2000g. The derived LRCL represent the average concentrations of contamination on the external surfaces of each WP that must not be exceeded before the WP is to be transported to the subsurface facility for emplacement. The evaluation of potential releases is necessary to control the potential contamination of the subsurface repository and to detect prematurely failed WPs. The detection of failed WPs is required in order to provide reasonable assurance that the integrity of each WP is intact prior to MGR closure. An emplaced WP may become breached due to manufacturing defects or improper weld combined with failure to detect the defect, by corrosion, or by mechanical penetration due to accidents or rockfall conditions. The breached WP may release its gaseous and volatile radionuclide content to the subsurface environment and result in contaminating the subsurface facility. The scope of this analysis is limited to radioactive contaminants resulting from breached WPs during the preclosure period of the subsurface repository. This report: (1) documents a method for deriving LRCL on the external surfaces of WP for acceptance into the subsurface repository; (2) provides a

  17. Use of Water Fluxmeters to Measure Drainage

    SciTech Connect

    Gee, Glendon W.; Ward, Andy L.; Zhang, Z. F.; Anandacoomaraswamy, A.

    2004-03-24

    Water supplies throughout the world are rapidly diminishing in quantity and quality. Efforts over the next decade must focus on methods which use water more efficiently for agriculture, industry, and recreational purposes, and at the same time reduce the potential for groundwater pollution. To assist in this effort, we have developed an improved method to simultaneously measure drainage quantity and quality using a water fluxmeter. Our water fluxmeter is a wick-lysimeter fitted with a small tipping-spoon and a solution-collection system. The only moving part is the tipping spoon. We have tested our fluxmeters under a range of conditions, from non-vegetated desert settings in Washington State USA, to irrigated tea plantations in Sri Lanka. Conditions of over-irrigation have been documented with our fluxmeters. When 4200 mm of water was applied to sandy soil via drip irrigation, at the Washington State site, over 3100 mm of drainage occurred. In contrast, at the same site, in the absence of both irrigation and vegetation, drainage was found to range from 0 mm/yr for a 1-m-deep silt loam soil to more than 100 mm/yr for a coarse-gravel surface. Solute transport, related to nitrate leaching can also be analyzed using water fluxmeters. Water fluxmeters have provided a reliable and inexpensive method to assess both quantity and quality of drainage waters over a wide range of environmental conditions.

  18. [Drainage in thyroid surgery].

    PubMed

    Ardito, G; Revelli, L; Guidi, M L; Murazio, M; Lucci, C; Modugno, P; Di Giovanni, V

    1999-01-01

    Bleeding represents a rare complication of thyroid surgery but when it occurs it may be life-threatening. To prevent this complication drainage is widely used. However no study has demonstrated the drains' value and recent reports have questioned its benefits. Therefore we have analyzed our experience of a 10 year-period in which 1.217 thyroidectomies were performed by the same surgical team and prophylactic routine drainage was always adopted. In 13 patients (1.06%) a benign hematoma occurred with spontaneous remission. In 6 patients the bleeding was severe and compressive hematoma occurred; it required surgical re-exploration. Such a complication is unusual in the neck surgery (0.49% in the authors' series) performed by experienced surgeons and when life-threatening hematomas do occur they depend on various uncontrolled factors and drainage is often not helpful. Otherwise a meticulous haemostatic technique is necessary and patients should be observed very closely during the few first hours following surgery on the thyroid gland. Therefore on the basis of the analysis of their series, although it is not always possible to prove the benefit of the drainage, the authors suggest its indication in the neck surgery, as in other fields with dead space, to remove blood and secretions reducing postoperative complications. They have never observed wound infections and patients were discharged within 72 hours.

  19. Drainage Water Filtration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tile drainage discharge from managed turf is known to carry elevated concentrations of agronomic fertilizers and chemicals. One approach being considered to reduce the transport is end-of-tile-filters. Laboratory and field studies have been initiated to address the efficacy of this approach. Result...

  20. Evaluation and localization of an artificial drainage network by 3D time-lapse electrical resistivity tomography.

    PubMed

    Jouen, T; Clément, R; Henine, H; Chaumont, C; Vincent, B; Tournebize, J

    2016-08-26

    In France, 10 % of total arable land is equipped with subsurface drainage systems, to control winter and spring waterlogging due to a temporary perched water table. Most of these systems were installed in the1980s and have aged since then and may now need maintenance. Sometimes, the location of the systems is known, but the standard situation in France is that the original as-built master sketches are no longer available. Performance assessment of drainage systems and curative actions are complicated since drain location is unknown. In this article, the authors test the application of a non-destructive drain detection method which consists in water injection at the outfall of the drainage network combined with time-lapse electrical resistivity tomography (ERT) monitoring. To assess the performance of this methodology, which consists in measuring electrical resistivity from electrodes placed at the nodes of a 1.2-m regular mesh, the authors interpreted the signal using a two-step approach. The first step is based on 3D ERT numerical modelling during a scenario of surface infiltration processes (forward modelling followed by geophysical inversion); this step optimizes the ERT method for locating the infiltration at depths below 1 m. The second step is the validation of the results obtained by numerical modelling with an experimental data set, using water injection into the drainage network combined with time-lapse ERT monitoring on an experimental field site. The results showed the relevance of time-lapse ERT monitoring on a small agricultural plot for locating the drainage network. The numerical results also showed several limitations of the combined methodology: (i) it is necessary to use an electrode spacing unit less than 1.20 m, which does not facilitate investigation on large agriculture plots, (ii) measurements must be taken when resistivity contrast is the strongest between the infiltration area and the soil and (iii) the volume of water needed for

  1. Best Practice -- Subsurface Investigations

    SciTech Connect

    Clark Scott

    2010-03-01

    These best practices for Subsurface Survey processes were developed at the Idaho National Laboratory (INL) and later shared and formalized by a sub-committee, under the Electrical Safety Committee of EFCOG. The developed best practice is best characterized as a Tier II (enhanced) survey process for subsurface investigations. A result of this process has been an increase in the safety and lowering of overall cost, when utility hits and their related costs are factored in. The process involves improving the methodology and thoroughness of the survey and reporting processes; or improvement in tool use rather than in the tools themselves. It is hoped that the process described here can be implemented at other sites seeking to improve their Subsurface Investigation results with little upheaval to their existing system.

  2. Wound Drainage Culture (For Parents)

    MedlinePlus

    ... Your 1- to 2-Year-Old Wound Drainage Culture KidsHealth > For Parents > Wound Drainage Culture Print A A A What's in this article? ... de heridas What It Is A wound drainage culture is a test to detect germs such as ...

  3. Improving the biodegradative capacity of subsurface bacteria

    SciTech Connect

    Romine, M.F.; Brockman, F.J.

    1993-04-01

    The continual release of large volumes of synthetic materials into the environment by agricultural and industrial sources over the last few decades has resulted in pollution of the subsurface environment. Cleanup has been difficult because of the relative inaccessibility of the contaminants caused by their wide dispersal in the deep subsurface, often at low concentrations and in large volumes. As a possible solution for these problems, interest in the introduction of biodegradative bacteria for in situ remediation of these sites has increased greatly in recent years (Timmis et al. 1988). Selection of biodegradative microbes to apply in such cleanup is limited to those strains that can survive among the native bacterial and predator community members at the particular pH, temperature, and moisture status of the site (Alexander, 1984). The use of microorganisms isolated from subsurface environments would be advantageous because the organisms are already adapted to the subsurface conditions. The options are further narrowed to strains that are able to degrade the contaminant rapidly, even in the presence of highly recalcitrant anthropogenic waste mixtures, and in conditions that do not require addition of further toxic compounds for the expression of the biodegradative capacity (Sayler et al. 1990). These obstacles can be overcome by placing the genes of well-characterized biodegradative enzymes under the control of promoters that can be regulated by inexpensive and nontoxic external factors and then moving the new genetic constructs into diverse groups of subsurface microbes. ne objective of this research is to test this hypothesis by comparing expression of two different toluene biodegradative enzymatic pathways from two different regulatable promoters in a variety of subsurface isolates.

  4. The Serpentinite Subsurface Microbiome

    NASA Astrophysics Data System (ADS)

    Schrenk, M. O.; Nelson, B. Y.; Brazelton, W. J.

    2011-12-01

    Microbial habitats hosted in ultramafic rocks constitute substantial, globally-distributed portions of the subsurface biosphere, occurring both on the continents and beneath the seafloor. The aqueous alteration of ultramafics, in a process known as serpentinization, creates energy rich, high pH conditions, with low concentrations of inorganic carbon which place fundamental constraints upon microbial metabolism and physiology. Despite their importance, very few studies have attempted to directly access and quantify microbial activities and distributions in the serpentinite subsurface microbiome. We have initiated microbiological studies of subsurface seeps and rocks at three separate continental sites of serpentinization in Newfoundland, Italy, and California and compared these results to previous analyses of the Lost City field, near the Mid-Atlantic Ridge. In all cases, microbial cell densities in seep fluids are extremely low, ranging from approximately 100,000 to less than 1,000 cells per milliliter. Culture-independent analyses of 16S rRNA genes revealed low-diversity microbial communities related to Gram-positive Firmicutes and hydrogen-oxidizing bacteria. Interestingly, unlike Lost City, there has been little evidence for significant archaeal populations in the continental subsurface to date. Culturing studies at the sites yielded numerous alkaliphilic isolates on nutrient-rich agar and putative iron-reducing bacteria in anaerobic incubations, many of which are related to known alkaliphilic and subsurface isolates. Finally, metagenomic data reinforce the culturing results, indicating the presence of genes associated with organotrophy, hydrogen oxidation, and iron reduction in seep fluid samples. Our data provide insight into the lifestyles of serpentinite subsurface microbial populations and targets for future quantitative exploration using both biochemical and geochemical approaches.

  5. Terrestrial Subsurface Ecosystem

    SciTech Connect

    Wilkins, Michael J.; Fredrickson, Jim K.

    2015-10-15

    The Earth’s crust is a solid cool layer that overlays the mantle, with a varying thickness of between 30-50 km on continental plates, and 5-10 km on oceanic plates. Continental crust is composed of a variety of igneous, metamorphic, and sedimentary rocks that weather and re-form over geologic cycles lasting millions to billions of years. At the crust surface, these weathered minerals and organic material combine to produce a variety of soils types that provide suitable habitats and niches for abundant microbial diversity (see Chapter 4). Beneath this soil zone is the subsurface. Once thought to be relatively free of microorganisms, recent estimates have calculated that between 1016-1017 g C biomass (2-19% of Earth’s total biomass) may be present in this environment (Whitman et al., 1998;McMahon and Parnell, 2014). Microbial life in the subsurface exists across a wide range of habitats: in pores associated with relatively shallow unconsolidated aquifer sediments to fractures in bedrock formations that are more than a kilometer deep, where extreme lithostatic pressures and temperatures are encountered. While these different environments contain varying physical and chemical conditions, the absence of light is a constant. Despite this, diverse physiologies and metabolisms enable microorganisms to harness energy and carbon for growth in water-filled pore spaces and fractures. Carbon and other element cycles are driven by microbial activity, which has implications for both natural processes and human activities in the subsurface, e.g., bacteria play key roles in both hydrocarbon formation and degradation. Hydrocarbons are a major focus for human utilization of the subsurface, via oil and gas extraction and potential geologic CO2 sequestration. The subsurface is also utilized or being considered for sequestered storage of high-level radioactive waste from nuclear power generation and residual waste from past production of weapons grade nuclear materials. While our

  6. Technical Analysis of In-Valley Drainage Management Strategies for the Western San Joaquin Valley, California

    USGS Publications Warehouse

    Presser, Theresa S.; Schwarzbach, Steven E.

    2008-01-01

    The western San Joaquin Valley is one of the most productive farming areas in the United States, but salt-buildup in soils and shallow groundwater aquifers threatens this area?s productivity. Elevated selenium concentrations in soils and groundwater complicate drainage management and salt disposal. In this document, we evaluate constraints on drainage management and implications of various approaches to management considered in: *the San Luis Drainage Feature Re-Evaluation (SLDFRE) Environmental Impact Statement (EIS) (about 5,000 pages of documentation, including supporting technical reports and appendices); *recent conceptual plans put forward by the San Luis Unit (SLU) contractors (i.e., the SLU Plans) (about 6 pages of documentation); *approaches recommended by the San Joaquin Valley Drainage Program (SJVDP) (1990a); and *other U.S. Geological Survey (USGS) models and analysis relevant to the western San Joaquin Valley. The alternatives developed in the SLDFRE EIS and other recently proposed drainage plans (refer to appendix A for details) differ from the strategies proposed by the San Joaquin Valley Drainage Program (1990a). The Bureau of Reclamation (USBR) in March 2007 signed a record of decision for an in-valley disposal option that would retire 194,000 acres of land, build 1,900 acres of evaporation ponds, and develop a treatment system to remove salt and selenium from drainwater. The recently proposed SLU Plans emphasize pumping drainage to the surface, storing approximately 33% in agricultural water re-use areas, treating selenium through biotechnology, enhancing the evaporation of water to concentrate salt, and identifying ultimate storage facilities for the remaining approximately 67% of waste selenium and salt. The treatment sequence of reuse, reverse osmosis, selenium bio-treatment, and enhanced solar evaporation is unprecedented and untested at the scale needed to meet plan requirements. All drainage management strategies that have been proposed

  7. Quantifying the dominant sources of sediment in a drained lowland agricultural catchment: The application of a thorium-based particle size correction in sediment fingerprinting

    NASA Astrophysics Data System (ADS)

    Foucher, Anthony; Laceby, Patrick J.; Salvador-Blanes, Sébastien; Evrard, Olivier; Le Gall, Marion; Lefèvre, Irène; Cerdan, Olivier; Rajkumar, Vignesh; Desmet, Marc

    2015-12-01

    Soil erosion is one of the main factors influencing land degradation and water quality at the global scale. Identifying the main sediment sources is therefore essential for the implementation of appropriate soil erosion mitigation measures. Accordingly, caesium-137 (137Cs) concentrations were used to determine the relative contribution of surface and subsurface erosion sources in a lowland drained catchment in France. As 137Cs concentrations are often dependent on particle size, specific surface area (SSA) and novel thorium (Th) based particle size corrections were applied. Surface and subsurface samples were collected to characterize the radionuclide properties of potential sources. Sediment samples were collected during one hydrological year and a sediment core was sampled to represent sediment accumulated over a longer temporal period. Additionally, sediment from tile drains was sampled to determine the radionuclide properties of sediment exported from the drainage network. A distribution modelling approach was used to quantify the relative sediment contributions from surface and subsurface sources. The results highlight a substantial enrichment in fine particles and associated 137Cs concentrations between the sources and the sediment. The application of both correction factors reduced this difference, with the Th correction providing a more accurate comparison of source and sediment samples than the SSA correction. Modelling results clearly indicate the dominance of surface sources during the flood events and in the sediment core. Sediment exported from the drainage network was modelled to originate predominantly from surface sources. This study demonstrates the potential of Th to correct for 137Cs particle size enrichment. More importantly, this research indicates that drainage networks may significantly increase the connectivity of surface sources to stream networks. Managing sediment transferred through drainage networks may reduce the deleterious effects of

  8. Drainage basins and channel incision on Mars.

    PubMed

    Aharonson, Oded; Zuber, Maria T; Rothman, Daniel H; Schorghofer, Norbert; Whipple, Kelin X

    2002-02-19

    Measurements acquired by the Mars Orbiter Laser Altimeter on board the Mars Global Surveyor indicate that large drainage systems on Mars have geomorphic characteristics inconsistent with prolonged erosion by surface runoff. We find the topography has not evolved to an expected equilibrium terrain form, even in areas where runoff incision has been previously interpreted. By analogy with terrestrial examples, groundwater sapping may have played an important role in the incision. Longitudinally flat floor segments may provide a direct indication of lithologic layers in the bedrock, altering subsurface hydrology. However, it is unlikely that floor levels are entirely due to inherited structures due to their planar cross-cutting relations. These conclusions are based on previously unavailable observations, including extensive piece-wise linear longitudinal profiles, frequent knickpoints, hanging valleys, and small basin concavity exponents.

  9. Acid mine drainage

    USGS Publications Warehouse

    Bigham, Jerry M.; Cravotta, Charles A.

    2016-01-01

    Acid mine drainage (AMD) consists of metal-laden solutions produced by the oxidative dissolution of iron sulfide minerals exposed to air, moisture, and acidophilic microbes during the mining of coal and metal deposits. The pH of AMD is usually in the range of 2–6, but mine-impacted waters at circumneutral pH (5–8) are also common. Mine drainage usually contains elevated concentrations of sulfate, iron, aluminum, and other potentially toxic metals leached from rock that hydrolyze and coprecipitate to form rust-colored encrustations or sediments. When AMD is discharged into surface waters or groundwaters, degradation of water quality, injury to aquatic life, and corrosion or encrustation of engineered structures can occur for substantial distances. Prevention and remediation strategies should consider the biogeochemical complexity of the system, the longevity of AMD pollution, the predictive power of geochemical modeling, and the full range of available field technologies for problem mitigation.

  10. Subsurface connection methods for subsurface heaters

    DOEpatents

    Vinegar, Harold J.; Bass, Ronald Marshall; Kim, Dong Sub; Mason, Stanley Leroy; Stegemeier, George Leo; Keltner, Thomas Joseph; Carl, Jr., Frederick Gordon

    2010-12-28

    A system for heating a subsurface formation is described. The system includes a first elongated heater in a first opening in the formation. The first elongated heater includes an exposed metal section in a portion of the first opening. The portion is below a layer of the formation to be heated. The exposed metal section is exposed to the formation. A second elongated heater is in a second opening in the formation. The second opening connects to the first opening at or near the portion of the first opening below the layer to be heated. At least a portion of an exposed metal section of the second elongated heater is electrically coupled to at least a portion of the exposed metal section of the first elongated heater in the portion of the first opening below the layer to be heated.

  11. Retrofitting for watershed drainage

    SciTech Connect

    Bennett, D.B. ); Heaney, J.P. )

    1991-09-01

    Over the past 8 years, degradation in Florida's Indian River Lagoon has taken the form of fish kills, reduced viable recreational and commercial fisheries, and loss of seagrass beds. Stormwater drainage practices in the watershed have been identified as the primary culprit in the slow demise of the lagoon. Specific drainage problems include an increased volume of freshwater runoff to the estuarine receiving water and deposition of organic sediments, reduced water clarity because of increased discharge of suspended solids and tea colored' groundwater - a result of drainage-canal-induced land dewatering, and eutrophication caused by nutrient loadings. In addition, poor flushing in lagoon segments makes runoff impacts even more damaging to the ecosystem. Recently, the lagoon has received national, regional, state, and local attention over its degradation and citizens' action and multi-agency efforts to restore it. To mitigate damage to the Indian River lagoon, agencies are considering alternatives such as retrofitting to reduce pollutant loads and implementing a more comprehensive watershed approach to stormwater management instead of individual controls on new development currently widely practiced. A comprehensive, long-term watershed control approach avoids unnecessary construction expenses, encourages cost-effective tradeoffs based on specific objectives, facilities performance monitoring, and accounts for cumulative impacts of continued growth in the watershed.

  12. Reducing nitrogen loss with managed drainage and polymer-coated urea.

    PubMed

    Nash, Patrick; Nelson, Kelly; Motavalli, Peter

    2015-01-01

    Continuous corn ( L.) production during dry years combined with high N fertilizer rates can have a high potential for NO-N loss through tile drainage water. Claypan soils can further increase the potential for NO-N loss through tile drainage water due to the claypan layer that restricts N leaching below the tile drains. The objective of this 4-yr study was to determine whether use of managed subsurface drainage (MD) in combination with a controlled-release N fertilizer could reduce the annual amount of NO-N loss through tile drainage water compared with free subsurface tile drainage (FD) with a noncoated urea application. Due to dry conditions over the summer and fall months, MD reduced the annual amount of water drained by at least 73% compared with FD in two of the four crop years. Low N loss and reduced corn N uptake possibly resulted in carry-over N and high soil N concentrations throughout the study, which may have limited the effect of N fertilizer source on annual NO-N loss in the tile drainage water. Use of MD reduced annual NO-N loss in the tile drainage water by 78 to 85% in two of the four years. High NO-N loss reduction with MD compared with FD was largely due to dry growing season conditions in combination with wet conditions over the noncropping period.

  13. Mars penetrator: Subsurface science mission

    NASA Technical Reports Server (NTRS)

    Lumpkin, C. K.

    1974-01-01

    A penetrator system to emplace subsurface science on the planet Mars is described. The need for subsurface science is discussed, and the technologies for achieving successful atmospheric entry, Mars penetration, and data retrieval are presented.

  14. 4R Water quality impacts: An assessment and synthesis of forty years of drainage nitrogen losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The intersection of agricultural drainage and nutrient mobility in the environment has led to multi-scale water quality concerns. This work reviewed and quantitatively analyzed nearly 1300 site-years of drainage nitrogen load data to develop a more comprehensive understanding of the impacts of 4Rs ...

  15. Tile Drainage Density Reduces Groundwater Travel Times and Compromises Riparian Buffer Effectiveness.

    PubMed

    Schilling, Keith E; Wolter, Calvin F; Isenhart, Thomas M; Schultz, Richard C

    2015-11-01

    Strategies to reduce nitrate-nitrogen (nitrate) pollution delivered to streams often seek to increase groundwater residence time to achieve measureable results, yet the effects of tile drainage on residence time have not been well documented. In this study, we used a geographic information system groundwater travel time model to quantify the effects of artificial subsurface drainage on groundwater travel times in the 7443-ha Bear Creek watershed in north-central Iowa. Our objectives were to evaluate how mean groundwater travel times changed with increasing drainage intensity and to assess how tile drainage density reduces groundwater contributions to riparian buffers. Results indicate that mean groundwater travel times are reduced with increasing degrees of tile drainage. Mean groundwater travel times decreased from 5.6 to 1.1 yr, with drainage densities ranging from 0.005 m (7.6 mi) to 0.04 m (62 mi), respectively. Model simulations indicate that mean travel times with tile drainage are more than 150 times faster than those that existed before settlement. With intensive drainage, less than 2% of the groundwater in the basin appears to flow through a perennial stream buffer, thereby reducing the effectiveness of this practice to reduce stream nitrate loads. Hence, strategies, such as reconnecting tile drainage to buffers, are promising because they increase groundwater residence times in tile-drained watersheds.

  16. Effects of cell surface characteristics and manure-application practices on Escherichia coli populations in the subsurface: A three-farm study

    NASA Astrophysics Data System (ADS)

    Salvucci, A. E.; Elton, M.; Siler, J. D.; Zhang, W.; Richards, B. K.; Geohring, L. D.; Warnick, L. D.; Hay, A. G.; Steenhuis, T.

    2010-12-01

    The introduction of microbial pathogens into the environment from untreated manure represents a threat to water quality and human health. Thus, understanding the effect of manure management strategies is imperative to effectively mitigate the inadvertent release of pathogens, particularly in subsurface environments where they can be transported through macropores to the groundwater or through agricultural tile line to open water bodies. The production of cell-surface biomolecules is also suspected to play an important role in the environmental survival and transport of enterobacterial pathogens. This study collected Escherichia coli samples from three dairy farms with artificial tile drainage systems and active manure spreading in the Central New York region over a three-month period. Sampling targeted four potential source locations on each farm: (i) cow housing, (ii) manure storage facilities, (iii) field soil, and (iv) subsurface drainage effluent. Over 2800 E. coli isolates were recovered and consequently analyzed for the cell surface components, cellulose and curli, traits associated with increased environmental survival, altered transport and pathogenicity. The E. coli isolates from locations i-iii displayed highly variable curli and cellulose-producing communities, while isolates collected from subsurface runoff on each farm had stable curli and cellulose production communities over all sampling dates. Furthermore, the method of manure application to the fields influenced the population characteristics found in drainage effluent isolates. Incorporation of manure into the soil was correlated to isolate populations largely deficient of curli and cellulose; whereas farms that only surface-applied manure were correlated to isolate populations of high curli and cellulose production. The production of curli and cellulose has previously been shown to be a response to environmental stress on the cell. Therefore, incorporation of manure directly into the soil appears

  17. Crop yield evaluation under controlled drainage in Ohio, United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drainage water management (NRCS Practice Code 554) is an important agricultural water management practice for reducing nitrate loading to surface water across the Midwest US. There may also be a positive crop yield benefit which could add incentive for adoption of the practice. Results from a three ...

  18. AMELIORATION OF ACID MINE DRAINAGE USING REACTIVE MIXTURES IN PERMEABLE REACTIVE BARRIERS

    EPA Science Inventory

    The generation and release of acidic drainage from mine wastes is an environmental problem of international scale. The use of zero-valent iron and/or iron mixtures in subsurface Permeable Reactive Barriers (PRB) presents a possible passive alternative for remediating acidic grou...

  19. Use of industrial byproducts to filter PO43- and pesticides in golf green drainage water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Golf courses are vulnerable to phosphate (PO43-) and pesticide loss by infiltration because of the sandy, porous grass rooting media used and presence of subsurface tile drainage. In this study, a blend of industrial byproducts, including granulated blast furnace slag (GBFS), cement kiln dust (CKD),...

  20. Effect of alternative surface inlet designs on sediment and phosphorus drainage losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine whether modifying open inlets by burying them in gravel capped with 30 cm of sandy clay loam soil or in ve...

  1. Shallow subsurface storm flow in a forested headwater catchment: Observations and modeling using a modified TOPMODEL

    USGS Publications Warehouse

    Scanlon, T.M.; Raffensperger, J.P.; Hornberger, G.M.; Clapp, R.B.

    2000-01-01

    Transient, perched water tables in the shallow subsurface are observed at the South Fork Brokenback Run catchment in Shenandoah National Park, Virginia. Crest piezometers installed along a hillslope transect show that the development of saturated conditions in the upper 1.5 m of the subsurface is controlled by total precipitation and antecedent conditions, not precipitation intensity, although soil heterogeneities strongly influence local response. The macroporous subsurface storm flow zone provides a hydrological pathway for rapid runoff generation apart from the underlying groundwater zone, a conceptualization supported by the two-storage system exhibited by hydrograph recession analysis. A modified version of TOPMODEL is used to simulate the observed catchment dynamics. In this model, generalized topographic index theory is applied to the subsurface storm flow zone to account for logarithmic storm flow recessions, indicative of linearly decreasing transmissivity with depth. Vertical drainage to the groundwater zone is required, and both subsurface reservoirs are considered to contribute to surface saturation.

  2. [Eye and lymph drainage].

    PubMed

    Grüntzig, J; Schicha, H; Huth, F

    1979-06-01

    Up to now lymphatics in the eye could not be pointed out. An ocular lymph drainage is denied. Földi succeeded in producing experimentally the syndrome of "lymphostatic encephalopathy and ophthalmopathy" by operative blockade of the cervical lymphatics in animals. In the first part of the present paper a historical view considering the subject "Eye and lymphatic system" is given. In the second part it is entered into the particulars of own experimental studies. As to our own investigations, rabbits have been injected 99mTc-sulfur-colloid, 99mTc-microcolloid, 99mTc-Albumin and 198Au-colloid into the retrobulbar space, anterior chamber, vitreous body and subconjuctival space of one eye. Measurements of the activity's distribution have been made in vivo with an Anger type camera (pho-Gamma-IV Hp, Searle Nuclear Chicago) and in vitro after section with a sodium iodine crystal well counter (Clinimat-200, Picker). In some animals the investigation has been combined with a bilateral dissection of the cervical lymph nodes. After injection in the retrobulbar space a significant concentration of the activity could be observed for the most part in the equilateral Lymphonodulus cervicalis profundus. By the cervical lymph blockade the removal of lymphoctopic substances from the retrobulbar space was largely inhibited. After injection in the anterior chamber a significant concentration could be observed for the most part in the equilateral Lymphonodulus cervicalis superficialis. After intravitreal injection a drainage to the bilateral deep cervical lymph nodes could be observed. After injection into the subconjunctival space a significant accumulation of activity could be registered in the equilateral Lymphonoduli mandibulares and cervicales superficiales. The data substantiate a segmental lymph drainage from the eye: vitreous body and retrobulbar space for the most part into the Lymphonoduli cervicales profundi, anterior chamber and subconjunctival space for the most part into

  3. Subsurface Ice Probe

    NASA Technical Reports Server (NTRS)

    Hecht, Michael; Carsey, Frank

    2005-01-01

    The subsurface ice probe (SIPR) is a proposed apparatus that would bore into ice to depths as great as hundreds of meters by melting the ice and pumping the samples of meltwater to the surface. Originally intended for use in exploration of subsurface ice on Mars and other remote planets, the SIPR could also be used on Earth as an alternative to coring, drilling, and melting apparatuses heretofore used to sample Arctic and Antarctic ice sheets. The SIPR would include an assembly of instrumentation and electronic control equipment at the surface, connected via a tether to a compact assembly of boring, sampling, and sensor equipment in the borehole (see figure). Placing as much equipment as possible at the surface would help to attain primary objectives of minimizing power consumption, sampling with high depth resolution, and unobstructed imaging of the borehole wall. To the degree to which these requirements would be satisfied, the SIPR would offer advantages over the aforementioned ice-probing systems.

  4. Lymph drainage in pregnant women.

    PubMed

    Cataldo Oportus, Sylvia; de Paiva Rodrigues, Lilian; Pereira de Godoy, José Maria; Guerreiro Godoy, Maria de Fátima

    2013-01-01

    Aim. The aim of this study was to evaluate the efficacy of lymph drainage to reduce edema of pregnant women. Method. Pregnant women (30 limbs) from the Obstetrics Outpatient Clinic of the Medical School of Santa Casa in São Paulo in the period December 2009 to May 2010 were enrolled in this quantitative, prospective study. The patients, in the 5th to 8th months of gestation, were submitted to one hour of manual lymph drainage of the legs. The volume of the legs was measured by water displacement volumetry before and after one hour of drainage using the Godoy & Godoy manual lymph drainage technique. The paired t-test was used for statistical analysis with an alpha error of 5% being considered significant. Results. Manual lymph drainage significantly reduced swelling of the legs of pregnant women during the day (P = 0.04). Conclusion. Manual lymph drainage helps to reduce limb size during the day of pregnant women.

  5. Subsurface contaminants focus area

    SciTech Connect

    1996-08-01

    The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites.

  6. Improving subsurface hydrology in Earth System Models

    NASA Astrophysics Data System (ADS)

    Volk, J. M.; Clark, M. P.; Swenson, S. C.; Lawrence, D. M.; Tyler, S. W.

    2015-12-01

    Hydrologic processes that govern storage and transport of soil water and groundwater can have strong dynamic relationships with biogeochemical and atmospheric processes. This understanding has lead to a push to improve subsurface hydrologic parametrization in Earth System Models. Here we present results related to improving the implementation of soil moisture distribution, groundwater recharge/discharge, and subsurface drainage in the Community Land Model (CLM) which is the land surface model in the Community Earth System Model. First we identified geo-climatically different locations around the world to develop test cases. For each case we compare the vertical soil moisture distribution from the different implementations of 1D Richards equation, considering the boundary conditions, the treatment of the groundwater sink term, the vertical discretization, and the time stepping schemes. Generally, large errors in the hydrologic mass balance within the soil column occur when there is a large vertical gradient in soil moisture or when there is a shallow water table within a soil column. We then test the sensitivity of the algorithmic parameters that control temporal discretization and error tolerance of the adaptive time-stepping scheme to help optimize its computational efficiency. In addition, we vary the spatial discretization of soil layers (i.e. quantity of layers and their thicknesses) to better understand the sensitivity of vertical discretization of soil columns on soil moisture variability in ESMs. We present multivariate and multi-scale evaluation for the different model options and suggest ways to move forward with future model improvements.

  7. Applications of subsurface microscopy.

    PubMed

    Tetard, Laurene; Passian, Ali; Farahi, Rubye H; Voy, Brynn H; Thundat, Thomas

    2012-01-01

    Exploring the interior of a cell is of tremendous importance in order to assess the effects of nanomaterials on biological systems. Outside of a controlled laboratory environment, nanomaterials will most likely not be conveniently labeled or tagged so that their translocation within a biological system cannot be easily identified and quantified. Ideally, the characterization of nanomaterials within a cell requires a nondestructive, label-free, and subsurface approach. Subsurface nanoscale imaging represents a real challenge for instrumentation. Indeed the tools available for high resolution characterization, including optical, electron or scanning probe microscopies, mainly provide topography images or require taggants that fluoresce. Although the intercellular environment holds a great deal of information, subsurface visualization remains a poorly explored area. Recently, it was discovered that by mechanically perturbing a sample, it was possible to observe its response in time with nanoscale resolution by probing the surface with a micro-resonator such as a microcantilever probe. Microcantilevers are used as the force-sensing probes in atomic force microscopy (AFM), where the nanometer-scale probe tip on the microcantilever interacts with the sample in a highly controlled manner to produce high-resolution raster-scanned information of the sample surface. Taking advantage of the existing capabilities of AFM, we present a novel technique, mode synthesizing atomic force microscopy (MSAFM), which has the ability to probe subsurface structures such as non-labeled nanoparticles embedded in a cell. In MSAFM mechanical actuators (PZTs) excite the probe and the sample at different frequencies as depicted in the first figure of this chapter. The nonlinear nature of the tip-sample interaction, at the point of contact of the probe and the surface of the sample, in the contact mode AFM configuration permits the mixing of the elastic waves. The new dynamic system comprises new

  8. Corn stover harvest increases herbicide movement to subsurface drains: RZWQM simulations

    USGS Publications Warehouse

    Shipitalo, Martin J.; Malone, Robert W.; Ma, Liwang; Nolan, Bernard T.; Kanwar, Rameshwar S.; Shaner, Dale L.; Pederson, Carl H.

    2016-01-01

    BACKGROUND Crop residue removal for bioenergy production can alter soil hydrologic properties and the movement of agrochemicals to subsurface drains. The Root Zone Water Quality Model (RZWQM), previously calibrated using measured flow and atrazine concentrations in drainage from a 0.4 ha chisel-tilled plot, was used to investigate effects of 50 and 100% corn (Zea mays L.) stover harvest and the accompanying reductions in soil crust hydraulic conductivity and total macroporosity on transport of atrazine, metolachlor, and metolachlor oxanilic acid (OXA). RESULTS The model accurately simulated field-measured metolachlor transport in drainage. A 3-yr simulation indicated that 50% residue removal decreased subsurface drainage by 31% and increased atrazine and metolachlor transport in drainage 4 to 5-fold when surface crust conductivity and macroporosity were reduced by 25%. Based on its measured sorption coefficient, ~ 2-fold reductions in OXA losses were simulated with residue removal. CONCLUSION RZWQM indicated that if corn stover harvest reduces crust conductivity and soil macroporosity, losses of atrazine and metolachlor in subsurface drainage will increase due to reduced sorption related to more water moving through fewer macropores. Losses of the metolachlor degradation product OXA will decrease due to the more rapid movement of the parent compound into the soil.

  9. Reconnecting tile drainage to riparian buffer hydrology for enhanced nitrate removal.

    PubMed

    Jaynes, D B; Isenhart, T M

    2014-03-01

    Riparian buffers are a proven practice for removing NO from overland flow and shallow groundwater. However, in landscapes with artificial subsurface (tile) drainage, most of the subsurface flow leaving fields is passed through the buffers in drainage pipes, leaving little opportunity for NO removal. We investigated the feasibility of re-routing a fraction of field tile drainage as subsurface flow through a riparian buffer for increasing NO removal. We intercepted an existing field tile outlet draining a 10.1-ha area of a row-cropped field in central Iowa and re-routed a fraction of the discharge as subsurface flow along 335 m of an existing riparian buffer. Tile drainage from the field was infiltrated through a perforated pipe installed 75 cm below the surface by maintaining a constant head in the pipe at a control box installed in-line with the existing field outlet. During 2 yr, >18,000 m (55%) of the total flow from the tile outlet was redirected as infiltration within the riparian buffer. The redirected water seeped through the 60-m-wide buffer, raising the water table approximately 35 cm. The redirected tile flow contained 228 kg of NO. On the basis of the strong decrease in NO concentrations within the shallow groundwater across the buffer, we hypothesize that the NO did not enter the stream but was removed within the buffer by plant uptake, microbial immobilization, or denitrification. Redirecting tile drainage as subsurface flow through a riparian buffer increased its NO removal benefit and is a promising management practice to improve surface water quality within tile-drained landscapes.

  10. Summary and conclusions from the SIWI Seminar for Young Water Professionals Drainage basin security--implications of virtual water trade and agricultural subsidies at regional, national and local levels.

    PubMed

    Johannessen, A

    2004-01-01

    This is a summary of the Young Water Professionals Seminar involving more than 50 young people from all over the world working with water. The presentations and following discussion were very lively and were about how subsidies and trade barriers imposed by the developed countries are influencing the income-generating capacity of millions of people in the developing world. Even though this is a very complex issue not easily resolved during the seminar it was also clear that there are some fundamental problems that need to be addressed. The importance of looking for solutions at different levels (i.e. local, regional, national) was highlighted as well as the policy of double standards, preaching free trade but only for the benefit of overdeveloped countries themselves. Further it was discussed how to achieve basin security through food security, and managing water for food security. The conclusion was that win-win solutions would be made if agricultural subsidies were to be completely removed.

  11. Investigation of the near subsurface using acoustic to seismic coupling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural, hydrological and civil engineering applications have realized a need for information of the near subsurface over large areas. In order to obtain this spatially distributed data over such scales, the measurement technique must be highly mobile with a short acquisition time. Therefore, s...

  12. Effects of drainage salinity evolution on irrigation management

    NASA Astrophysics Data System (ADS)

    Kan, Iddo

    2003-12-01

    A soil physics theory of solute movement through a drained saturated zone underlying agricultural land is introduced into a long-term economic analysis of farm-level irrigation management; this is an alternative to the immediate, homogeneous blending assumption employed in previous studies as a base for calculating changes in drainage salinity over time. Using data from California, the effect of drainage salinity evolution is analyzed through a year-by-year profit optimization under the requirement of on-farm drainage disposal. Paths of optimal land allocation among crop production with fresh surface water, saline drainage reuse and evaporation ponds appear to depend on the relative profitability of the first two; that of reuse is affected by the trend of drainage salinity. Tile spacing and environmental regulations associated with evaporation ponds affect the timing of evaporation pond construction. The system converges into a solution involving both drainage-disposal activities; this solution includes an outlet for salts and is therefore sustainable. Following this strategy, the system is asymptotically approaching a steady state that possesses both hydrological and salt balances. Economic implications associated with land retirement programs in California are discussed.

  13. Energy for agriculture in Pakistan

    NASA Astrophysics Data System (ADS)

    Jameel, M.

    1982-05-01

    The energy implications of different farm mechanization and macronutrient supply scenarios were examined. Results show that up to the year 2000, fertilizer production and irrigation-drainage account for 45 % and 40 %, respectively, of total energy input to agriculture. Tractors, threshers, and pesticides share the rest.

  14. A steady state solution for ditch drainage problem with special reference to seepage face and unsaturated zone flow contribution: Derivation of a new drainage spacing eqaution

    NASA Astrophysics Data System (ADS)

    Yousfi, Ammar; Mechergui, Mohammed

    2016-04-01

    The seepage face is an important feature of the drainage process when recharge occurs to a permeable region with lateral outlets. Examples of the formation of a seepage face above the downstream water level include agricultural land drained by ditches. Flow problem to these drains has been investigated extensively by many researchers (e.g. Rubin, 1968; Hornberger et al. 1969; Verma and Brutsaert, 1970; Gureghian and Youngs, 1975; Vauclin et al., 1975; Skaggs and Tang, 1976; Youngs, 1990; Gureghian, 1981; Dere, 2000; Rushton and Youngs, 2010; Youngs, 2012; Castro-Orgaz et al., 2012) and may be tackled either using variably saturated flow models, or the complete 2-D solution of Laplace equation, or using the Dupuit-Forchheimer approximation; the most widely accepted methods to obtain analytical solutions for unconfined drainage problems. However, the investigation reported by Clement et al. (1996) suggest that accounting for the seepage face alone, as in the fully saturated flow model, does not improve the discharge estimate because of disregarding flow the unsaturated zone flow contribution. This assumption can induce errors in the location of the water table surface and results in an underestimation of the seepage face and the net discharge (e.g. Skaggs and Tang, 1976; Vauclin et al., 1979; Clement et al., 1996). The importance of the flow in the unsaturated zone has been highlighted by many authors on the basis of laboratory experiments and/or numerical experimentations (e.g. Rubin, 1968; Verma and Brutsaert, 1970; Todsen, 1973; Vauclin et al., 1979; Ahmad et al., 1993; Anguela, 2004; Luthin and Day, 1955; Shamsai and Narasimhan, 1991; Wise et al., 1994; Clement et al., 1996; Boufadel et al., 1999; Romano et al., 1999; Kao et al., 2001; Kao, 2002). These studies demonstrate the failure of fully saturated flow models and suggested that the error made when using these models not only depends on soil properties but also on the infiltration rate as reported by Kao et

  15. Subsurface fracture spacing

    SciTech Connect

    Lorenz, J.C. ); Hill, R.E. )

    1991-01-01

    This study was undertaken in order to document and analyze the unique set of data on subsurface fracture characteristics, especially spacing, provided by the US Department of Energy's Slant Hole Completion Test well (SHCT-1) in the Piceance Basin, Colorado. Two hundred thirty-six (236) ft (71.9 m) of slant core and 115 ft (35.1 m) of horizontal core show irregular, but remarkably close, spacings for 72 natural fractures cored in sandstone reservoirs of the Mesaverde Group. Over 4200 ft (1280 m) of vertical core (containing 275 fractures) from the vertical Multiwell Experiment wells at the same location provide valuable information on fracture orientation, termination, and height, but only data from the SHCT-1 core allow calculations of relative fracture spacing. Within the 162-ft (49-m) thick zone of overlapping core from the vertical and deviated wellbores, only one fracture is present in vertical core whereas 52 fractures occur in the equivalent SHCT-1 core. The irregular distribution of regional-type fractures in these heterogeneous reservoirs suggests that measurements of average fracture spacing'' are of questionable value as direct input parameters into reservoir engineering models. Rather, deviated core provides data on the relative degree of fracturing, and confirms that cross fractures can be rare in the subsurface. 13 refs., 11 figs.

  16. Subsurface Biogeochemistry of Actinides

    SciTech Connect

    Kersting, Annie B.; Zavarin, Mavrik

    2016-06-29

    A major scientific challenge in environmental sciences is to identify the dominant processes controlling actinide transport in the environment. It is estimated that currently, over 2200 metric tons of plutonium (Pu) have been deposited in the subsurface worldwide, a number that increases yearly with additional spent nuclear fuel (Ewing et al., 2010). Plutonium has been shown to migrate on the scale of kilometers, giving way to a critical concern that the fundamental biogeochemical processes that control its behavior in the subsurface are not well understood (Kersting et al., 1999; Novikov et al., 2006; Santschi et al., 2002). Neptunium (Np) is less prevalent in the environment; however, it is predicted to be a significant long-term dose contributor in high-level nuclear waste. Our focus on Np chemistry in this Science Plan is intended to help formulate a better understanding of Pu redox transformations in the environment and clarify the differences between the two long-lived actinides. The research approach of our Science Plan combines (1) Fundamental Mechanistic Studies that identify and quantify biogeochemical processes that control actinide behavior in solution and on solids, (2) Field Integration Studies that investigate the transport characteristics of Pu and test our conceptual understanding of actinide transport, and (3) Actinide Research Capabilities that allow us to achieve the objectives of this Scientific Focus Area (SFA and provide new opportunities for advancing actinide environmental chemistry. These three Research Thrusts form the basis of our SFA Science Program (Figure 1).

  17. Preoperative biliary drainage in Perihilar Cholangiocarcinoma: Identifying patients who require percutaneous drainage after failed endoscopic drainage

    PubMed Central

    Wiggers, Jimme K; Koerkamp, Bas Groot; Coelen, Robert J; Rauws, Erik A; Schattner, Mark A; Nio, C Yung; Brown, Karen T; Gonen, Mithat; van Dieren, Susan; van Lienden, Krijn P; Allen, Peter J; Besselink, Marc GH; Busch, Olivier RC; D’Angelica, Michael I; DeMatteo, Robert P; Gouma, Dirk J; Kingham, T Peter; Jarnagin, William R; van Gulik, Thomas M

    2016-01-01

    Background and study aims Preoperative biliary drainage is often initiated with endoscopic retrograde cholangiopancreatography (ERCP) in patients with potentially resectable perihilar cholangiocarcinoma (PHC), but additional percutaneous transhepatic catheter (PTC) drainage is frequently required. This study aimed to develop and validate a prediction model to identify patients with a high risk of inadequate ERCP drainage. Patients and Methods Patients with potentially resectable PHC and preoperative (attempted) ERCP drainage were included from two specialty center cohorts between 2001 and 2013. Indications for additional PTC drainage were failure to place an endoscopic stent, failure to relieve jaundice, cholangitis, or insufficient drainage of the future liver remnant. A prediction model was derived from the European cohort and externally validated in the USA cohort. Results 108 of 288 patients (38%) required additional preoperative PTC after inadequate ERCP drainage. Independent risk factors for additional PTC were proximal biliary obstruction on preoperative imaging (Bismuth 3 or 4) and pre-drainage total bilirubin level. The prediction model identified three subgroups: patients with a low risk of 7%, a moderate risk of 40%, and a high risk of 62%. The high-risk group consisted of patients with a total bilirubin level above 150 μmol/L and Bismuth 3a or 4 tumours, who typically require preoperative drainage of the angulated left bile ducts. The prediction model had good discrimination (AUC 0.74) and adequate calibration in the external validation cohort. Conclusions Selected patients with potentially resectable PHC have a high risk (62%) of inadequate preoperative ERCP drainage requiring additional PTC. These patients might do better with initial PTC instead of ERCP. PMID:26382308

  18. The role of recharge zones, discharge zones, springs and tile drainage systems in peneplains of Central European highlands with regard to water quality generation processes

    NASA Astrophysics Data System (ADS)

    Dolezal, F.; Kvitek, T.

    2003-04-01

    Large areas of ploughed lands in old peneplains of Central Europe (such as the Bohemo-Moravian Highland) are located on flat tops of hills. Their soils, mostly Cambisols on weathered acid crystalline rocks (e.g., granite and gneiss) are permeable and shallow or medium-deep. These are the zones of groundwater recharge and it is through them that the local water-bearing formations (weathered rocks, colluvia and quaternary sediments in valleys) receive their portions of nitrate and other pollutants. The groundwater exfiltrates on the lower parts of slopes and in narrow valleys, creating dispersed springs and waterlogged areas. The latter were traditionally used, if at all, as forests or meadows. Since about 1960, many of the former meadows in foothill zones of Czech highlands have been drained by subsurface tile drainage systems and turned into arable lands. Field measurements in several small experimental catchments in this area proved that the water which is being discharged into the main stream either by small surface tributaries collecting water from subsurface drainage systems or by the subsurface drainage systems themselves reveals high concentrations of nitrate. Strong intraseasonal variation of water quality and the results of runoff separation suggest that the overall turnover of groundwater is fast. It is hypothesised that the redox status of the formerly waterlogged sites has been shifted toward the oxidation side due to drainage and tillage, rendering the removal of nitrogen from groundwater by denitrification less efficient. Hence, it is mainly the combination of diffuse pollution by nitrate in the recharge zones and the lack of opportunity for denitrification in the transitional and discharge zones which makes the stream water polluted. The ploughed lands in the recharge zones represent an established basis for local agriculture and cannot be set aside. Many of them have however been declared as vulnerable zones in terms of the nitrate pollution risk

  19. Nonintrusive subsurface surveying capability

    SciTech Connect

    Tunnell, T.W.; Cave, S.P.

    1994-06-01

    This presentation describes the capabilities of a ground-pentrating radar (GPR) system developed by EG&G Energy Measurements (EM), a prime contractor to the Department of Energy (DOE). The focus of the presentation will be on the subsurface survey of DOE site TA-21 in Los Alamos, New Mexico. EG&G EM developed the system for the Department of Defense. The system is owned by the Department of the Army and currently resides at KO in Albuquerque. EM is pursuing efforts to transfer this technology to environmental applications such as waste-site characterization with DOE encouragement. The Army has already granted permission to use the system for the waste-site characterization activities.

  20. Containment of subsurface contaminants

    DOEpatents

    Corey, J.C.

    1994-09-06

    A barrier is disclosed for reducing the spread of a plume of subsurface contaminants. The apparatus includes a well system for injecting a fluid, such as air, just outside and below the periphery of the plume. The fluid is injected at a pressure sufficient to lower the hydraulic conductivity of the soil from the point of injection to the surface thus establishing a curtain-like barrier to groundwater movement. The barrier is established upgradient of the plume to divert groundwater away, or preferably completely around the plume to reduce the flow of groundwater into or out of the plume. The barrier enables the remediation of the confined contamination and then, when the injection of the fluid is halted, the barrier quickly dissipates. 5 figs.

  1. Containment of subsurface contaminants

    DOEpatents

    Corey, John C.

    1994-01-01

    A barrier for reducing the spread of a plume of subsurface contaminants. The apparatus includes a well system for injecting a fluid, such as air, just outside and below the periphery of the plume. The fluid is injected at a pressure sufficient to lower the hydraulic conductivity of the soil from the point of injection to the surface thus establishing a curtain-like barrier to groundwater movement. The barrier is established upgradient of the plume to divert groundwater away, or preferably completely around the plume to reduce the flow of groundwater into or out of the plume. The barrier enables the remediation of the confined contamination and then, when the injection of the fluid is halted, the barrier quickly dissipates.

  2. Surface runoff and tile drainage transport of phosphorus in the Midwestern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Midwestern US offers some of the most productive agricultural soils in the world. Given the cool humid climate, much of the region would not be able to support agriculture without drainage, as the high water table would potentially damage crops and not allow machinery to be in the fields at crit...

  3. Identifying sediment sources in a drained lowland agricultural catchment: the application of a novel thorium-based particle size correction in sediment fingerprinting

    NASA Astrophysics Data System (ADS)

    Laceby, J. P.; Le Gall, M.; Foucher, A.; Salvador-Blanes, S.; Evrard, O.; Lefèvre, I.; Cerdan, O.; Desmet, M.

    2015-12-01

    Soil erosion is one of the main processes influencing land and water degradation at the global scale. Identifying the main sediment sources is therefore essential for effective soil erosion management. Accordingly, caesium-137 (137Cs) concentrations were used to quantify the relative contribution of surface and subsurface erosion sources in a lowland drained catchment in France. As 137Cs concentrations are often dependent on particle size, specific surface area (SSA) and novel Thorium (Th) based particle size corrections were applied. Surface and subsurface samples were collected to characterize the radionuclide properties of potential sources. Sediment samples were collected during one hydrological year and a sediment core was sampled to represent sediment accumulated over a longer temporal period. Additionally, sediment from tile drains was sampled to determine the radionuclide properties of sediment exported from the drainage network. The results highlight a substantial enrichment in fine particles and associated 137Cs concentrations between the sources and the sediment. The application of both correction factors reduced this difference, with the Th correction providing a more accurate comparison of source and sediment samples than the SSA correction. Modelling results clearly indicate the dominance of surface sources during the flood events and in the sediment core. Sediment exported from the drainage network was modelled to originate predominantly from surface sources. This study demonstrates the potential of Th to correct for 137Cs particle size enrichment. More importantly, this research indicates that drainage networks may significantly increase the connectivity of surface sources to stream networks. Managing sediment transferred through drainage networks may reduce the deleterious effects of suspended sediment loads on riverine systems in similar lowland drained agricultural catchments.

  4. Subsurface Samples: Collection and Processing

    SciTech Connect

    Long, Philip E.; Griffin, W. Timothy; Phelps, Tommy J.

    2002-12-01

    Microbiological data, interpretation, and conclusions from subsurface samples ultimately depend on the quality and representative character of the samples. Subsurface samples for environmental microbiology ideally contain only the microbial community and geochemical properties that are representative of the subsurface environment from which the sample was taken. To that end, sample contamination by exogenous microorganisms or chemical constituents must be eliminated or minimized, and sample analyses need to begin before changes in the microbial community or geochemical characteristics occur. This article presents sampling methods and sample processing techniques for collecting representative samples from a range of subsurface environments. Factors that should be considered when developing a subsurface sampling program are discussed, including potential benefits, costs, and limitations enabling researchers to evaluate the techniques that are presented and match them to their project requirements. Methods and protocols to address coring, sampling, processing and quality assessment issues are presented.

  5. An Automated Approach to Agricultural Tile Drain Detection and Extraction Utilizing High Resolution Aerial Imagery and Object-Based Image Analysis

    NASA Astrophysics Data System (ADS)

    Johansen, Richard A.

    Subsurface drainage from agricultural fields in the Maumee River watershed is suspected to adversely impact the water quality and contribute to the formation of harmful algal blooms (HABs) in Lake Erie. In early August of 2014, a HAB developed in the western Lake Erie Basin that resulted in over 400,000 people being unable to drink their tap water due to the presence of a toxin from the bloom. HAB development in Lake Erie is aided by excess nutrients from agricultural fields, which are transported through subsurface tile and enter the watershed. Compounding the issue within the Maumee watershed, the trend within the watershed has been to increase the installation of tile drains in both total extent and density. Due to the immense area of drained fields, there is a need to establish an accurate and effective technique to monitor subsurface farmland tile installations and their associated impacts. This thesis aimed at developing an automated method in order to identify subsurface tile locations from high resolution aerial imagery by applying an object-based image analysis (OBIA) approach utilizing eCognition. This process was accomplished through a set of algorithms and image filters, which segment and classify image objects by their spectral and geometric characteristics. The algorithms utilized were based on the relative location of image objects and pixels, in order to maximize the robustness and transferability of the final rule-set. These algorithms were coupled with convolution and histogram image filters to generate results for a 10km2 study area located within Clay Township in Ottawa County, Ohio. The eCognition results were compared to previously collected tile locations from an associated project that applied heads-up digitizing of aerial photography to map field tile. The heads-up digitized locations were used as a baseline for the accuracy assessment. The accuracy assessment generated a range of agreement values from 67.20% - 71.20%, and an average

  6. Contrasting nitrogen fate in watersheds using agricultural and water quality information

    USGS Publications Warehouse

    Essaid, Hedeff I.; Baker, Nancy T.; McCarthy, Kathleen A.

    2016-01-01

    Surplus nitrogen (N) estimates, principal component analysis (PCA), and end-member mixing analysis (EMMA) were used in a multisite comparison contrasting the fate of N in diverse agricultural watersheds. We applied PCA-EMMA in 10 watersheds located in Indiana, Iowa, Maryland, Nebraska, Mississippi, and Washington ranging in size from 5 to 1254 km2 with four nested watersheds. Watershed Surplus N was determined by subtracting estimates of crop uptake and volatilization from estimates of N input from atmospheric deposition, plant fixation, fertilizer, and manure for the period from 1987 to 2004. Watershed average Surplus N ranged from 11 to 52 kg N ha−1 and from 9 to 32% of N input. Solute concentrations in streams, overland runoff, tile drainage, groundwater (GW), streambeds, and the unsaturated zone were used in the PCA-EMMA procedure to identify independent components contributing to observed stream concentration variability and the end-members contributing to streamflow and NO3 load. End-members included dilute runoff, agricultural runoff, benthic-processing, tile drainage, and oxic and anoxic GW. Surplus N was larger in watersheds with more permeable soils (Washington, Nebraska, and Maryland) that allowed greater infiltration, and oxic GW was the primary source of NO3 load. Subsurface transport of NO3 in these watersheds resulted in some removal of Surplus N by denitrification. In less permeable watersheds (Iowa, Indiana, and Mississippi), NO3 was rapidly transported to the stream by tile drainage and runoff with little removal. Evidence of streambed removal of NO3 by benthic diatoms was observed in the larger watersheds.

  7. Sustaining Irrigated Agriculture in Arid Areas: Lessons Learned in the San Joaquin Valley

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The conventional wisdom is that drainage is required to sustain irrigation in arid and semiarid areas. However, disposal of saline drainage water is a problem throughout the world that is challenging the sustainability of irrigated agriculture. The presence of elements besides salt in the drainage w...

  8. Complex hydrologic changes in frequency-magnitude response due to shifting agricultural practices in the Midwestern U.S.

    NASA Astrophysics Data System (ADS)

    Takbiri, Z.; Czuba, J. A.; Foufoula-Georgiou, E.

    2014-12-01

    Hydrologic change is occurring in many basins throughout the Midwestern U.S. not only in the mean annual streamflow but across a spectrum of magnitudes and frequencies. Disentangling the causative mechanisms responsible for these changes such as anthropogenic factors, e.g., artificial drainage to increase agricultural productivity, and climatic shifts in precipitation patterns is important for planning effective mitigation strategies. We have begun unraveling these changes in a human impacted agricultural landscape in the Midwestern U.S., specifically two subbasins of the Minnesota River Basin in Minnesota: the Redwood and Whetstone River Basins, where there has been a shift in agriculture from small grains to soybeans. This shift occurred at different times for each basin (1976 and 1991, respectively) and when soy covered about 20% of the basin area an apparent shift in the hydrologic regime also occurred as evidence by visual inspection of the hydrographs. Precisely quantifying the nature of this hydrologic regime shift however is a challenge and this work adds in this direction. Using Copulas and the joint probability distribution of daily precipitation and streamflow, we quantified a significantly higher dependence between precipitation and streamflow increments in the mid-quantiles (0.1-0.6; attributed to the artificial drainage to the stream rather than the slower infiltration and subsurface runoff) and no significant change for high quantiles (because for extreme storms the artificially fast drainage does not differ much hydrologically from the naturally fast overland flow). We further performed a multi-scale analysis of streamflow increments via wavelets to quantify the changes in the magnitude and frequency of the rising and falling limbs of hydrographs, confirming the above findings. Since precipitation changes were confirmed not to be significant, it is suggested that streamflow changes are largely driven by a change in land use and not climate in these

  9. Use of industrial byproducts to filter nutrients and pesticides in a golf green’s drainage water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Golf courses are particularly vulnerable to phosphate (PO43-) and pesticide loss by infiltration because of the sandy, porous grass rooting media used and presence of subsurface tile drainage. In this study, an effort was made to filter PO43-, chlorothalonil, mefenoxam, and propiconazole in putting ...

  10. Surface expressions of subsurface structures in parts of the Michigan and Illinois basins

    SciTech Connect

    Herman, J.D. )

    1991-08-01

    Study of glacial geology, stream drainage, bedrock topography, and subsurface structure maps in Isabella, Midland, Arenac, Gladwin, Clare, Ogemaw, Iosco, Mecosta, and Montcalm counties in Michigan revealed distinct correlations between patterns and types of glacial deposits and subsurface structures. Anticlinal structures associated with the Mt. Pleasant, North Buckeye, and South Buckeye, Hamilton, Deep River, Clayton, Logan, Six Lakes, and West Branch oil and gas fields occur along areas where northeast-trending glacial moraines and truncated, attenuated, or deviated. Furthermore, these anticlinal structures are associated with lacustrine sands and gravels and glacial outwash deposits nearly surrounded by glacial tills or lacustrine sands and clays. All of the anticlinal structures are associated with bedrock topography highs and alignment of streams parallel to the trends of the structures. Comparison of images of subsurface structure and surface elevation data covering the northern part of the illinois basin showed distinct correlations between glacial moraine patterns and subsurface structural trends. The Pesotum and Arcola end moraines bracket the major anticlinal structure at the Hayes oil field. The Westfield, Nevins, and Paris moraines are truncated or attenuated where they intersect the surface projections of the subsurface LaSalle anticlinal belt and the anticlinal structure associated with the Mattoon oil field. These correlations among subsurface structure, bedrock topography, and surface glacial features indicate that the subsurface structural configuration influenced glacial depositional patterns in detectable and predictable ways, even in areas blanketed by over 100 ft of Wisconsin glacial drift.

  11. Connecting Surface Planting with Subsurface Erosion Due to Groundwater Flow

    NASA Astrophysics Data System (ADS)

    Reardon, M.; Curran, J. C.

    2014-12-01

    Bank erosion and failure is a major contributor of fine sediment to streams and rivers, and can be driven by subsurface flow. In restoration projects, vegetation is often planted on banks to reduce erosion and stabilize the banks. However, the relationship between subsurface flow, erosion and vegetation remains somewhat speculative. A comparative study quantified the effect of surface planting on subsurface erosion and soil strength. Six 32-gallon containers were layered with a sandy loam overlying a highly conductive sand layer and a confining clay. Three treatments were applied in pairs: switchgrass (Panicum virgatum L.), sod (turf-type tall fescue and Kentucky bluegrass mix), and no vegetation. After a vegetation establishment period, the 2, 10, and 100 year rainfalls were simulated. Samples collected from ports in the containers were analyzed for subsurface drainage volume and suspended sediment concentration. After all rainfall simulations, a sediment core was taken from each container to measure shear strength and root density. Results indicate the relative benefits of vegetative planting to reduce subsurface erosion during storms and enhance soil strength. Switchgrass reduced the total amount of sediment removed from containers during all three storms when compared to the sod and during the 10 and 100 year storms when compared to the bare ground. Results from the volume analysis were more variable. Switchgrass retained the greatest volume of water from the 100 year storm event, but also released the largest fraction of water in the 2 and 10 year storms. Both sod and switchgrass planting considerably increased the time required for the soil samples to fail despite reducing the shear stress at failure. Where switchgrass grew long, woody roots, the sod developed a dense mat of interconnected thin roots. We suspect the different root patterns between sod and switchgrass to be a dominant factor in the response of the different containers.

  12. Microbial Transport in the Subsurface

    SciTech Connect

    Ginn, Timothy R.; Camesano, Terri; Scheibe, Timothy D.; Nelson, Kirk B.; Clement, T. P.; Wood, Brian D.

    2005-12-01

    In this article we focus on the physical, chemical, and biological processes involved in the transport of bacteria in the saturated subsurface. We will first review conceptual models of bacterial phases in the subsurface, and then the processes controlling fate and transport on short (e.g., bioremediation) time scales. Finally we briefly review field bacterial transport experiments and discuss a number of issues that impact the application of current process descriptions and models at the field scale.

  13. Heimlich valve for chest drainage.

    PubMed

    Heimlich, H J

    1983-01-01

    The Heimlich chest drainage valve was developed so that the process of draining the pleural cavity could be accomplished in a safe, relatively simple, and efficient manner. Replacing the cumbersome underwater drainage bottle system, the Heimlich valve connects to chest tubing and allows fluid and air to pass in one direction only. The valve, which functions in any position, need never be clamped, and regulated suction can be attached to it if necessary. The valve drains into a plastic bag that can be held at any level, allowing the patient undergoing chest drainage to be ambulatory simply by carrying the bag. The construction and function of the valve is easily understood by medical and nursing staffs. It is presterilized, stored in a sterile package, and readily utilized on emergency vehicles and in the operating room.

  14. Fate and Transport of Agricultural Nutrients in Macro-porous Soils

    NASA Astrophysics Data System (ADS)

    Royem, A. A.; Walter, M. T.

    2010-12-01

    The major objective of this study is to address water quality problems associated with application of liquid manure to subsurface-drained agricultural lands. There are over 600 large and medium sized confined animal feeding operations (CAFOs) in New York, most of which utilize land application to manage this waste stream. Due to the regions shallow soil and humid weather, most fields have been equipped with tile drainage. The concern is that handling the manure is a liquefied state may enhance the likelihood of contamination of the tile drainage discharge and its potential impacts on downstream water quality. Laboratory studies were used to investigate how manure liquidity (percent solids) affects the transport of manure constituents through varying macropore sizes in the soil. Soil columns of 3 different macropore sizes (0, 1, 3 millimeter) were constructed, subjected to simulated rainfall over several weeks, and effluent was collected from both the soil matrix and macropores separately. Effluent samples were analyzed for soluble reactive phosphorus (SRP). As expected, the preliminary results show enhanced SRP transport through macropores with decreasing percent solids (i.e., more liquidy manure). The implications at field and watershed scales are still being investigated.

  15. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Tulare Lake bed area, southern San Joaquin Valley, California, 1986-87

    USGS Publications Warehouse

    Schroeder, R.A.; Palawski, D.U.; Skorupa, J.P.

    1988-01-01

    Concentrations of numerous toxic trace elements and pesticides were measured during 1986 in water, sediment, and biota from three areas near the Tulare Lake Bed, southern San Joaquin Valley, California: Kern National Wildlife Refuge, Pixley National Wildlife Refuge, and Westfarmers evaporation ponds about 5 mi west of Kern National Wildlife Refuge, to determine whether toxic constituents in agricultural-irrigation drainage pose a threat to beneficial uses of water, especially to uses by wildlife. Pesticide residues were found to be low at all three areas. Trace element concentrations were found to be comparatively low at the Kern and Pixley National Wildlife Refuge areas and high at the Westfarmers evaporation ponds. Dissolved selenium concentrations were < 1 micrograms/L (ug/L) in areas on and adjacent to the refuges, but ranged from 110 to 360 ug/L in the saline drainwater impounded in the evaporation ponds. The ratio of mean selenium concentrations in biota from Westfarmers ponds compared to biota from Kesterson National Wildlife Refuge (where adverse effects have been documented) is 5 for waterboatman, 2 for avocet liver, 1 for avocet eggs, and < 1 for widgeongrass. The low concentrations measured at Kern and Pixley National Wildlife Refuges suggest that trace elements and pesticides pose little threat to wildlife there; however, impounded subsurface drainage from agricultural irrigation does pose a threat to wildlife at the nearby Westfarmers ponds. Preliminary results of surveys conducted in 1987 indicated that there are adverse biological effects on shorebirds nesting at the ponds, although interpretation of the magnitude of the effects is premature, pending completion of ongoing studies by the U.S. Fish and Wildlife Service. (Author 's abstract)

  16. Subsurface Geotechnical Parameters Report

    SciTech Connect

    D. Rigby; M. Mrugala; G. Shideler; T. Davidsavor; J. Leem; D. Buesch; Y. Sun; D. Potyondy; M. Christianson

    2003-12-17

    The Yucca Mountain Project is entering a the license application (LA) stage in its mission to develop the nation's first underground nuclear waste repository. After a number of years of gathering data related to site characterization, including activities ranging from laboratory and site investigations, to numerical modeling of processes associated with conditions to be encountered in the future repository, the Project is realigning its activities towards the License Application preparation. At the current stage, the major efforts are directed at translating the results of scientific investigations into sets of data needed to support the design, and to fulfill the licensing requirements and the repository design activities. This document addresses the program need to address specific technical questions so that an assessment can be made about the suitability and adequacy of data to license and construct a repository at the Yucca Mountain Site. In July 2002, the U.S. Nuclear Regulatory Commission (NRC) published an Integrated Issue Resolution Status Report (NRC 2002). Included in this report were the Repository Design and Thermal-Mechanical Effects (RDTME) Key Technical Issues (KTI). Geotechnical agreements were formulated to resolve a number of KTI subissues, in particular, RDTME KTIs 3.04, 3.05, 3.07, and 3.19 relate to the physical, thermal and mechanical properties of the host rock (NRC 2002, pp. 2.1.1-28, 2.1.7-10 to 2.1.7-21, A-17, A-18, and A-20). The purpose of the Subsurface Geotechnical Parameters Report is to present an accounting of current geotechnical information that will help resolve KTI subissues and some other project needs. The report analyzes and summarizes available qualified geotechnical data. It evaluates the sufficiency and quality of existing data to support engineering design and performance assessment. In addition, the corroborative data obtained from tests performed by a number of research organizations is presented to reinforce

  17. Management of sediment and erosion processes in boreal headwaters affected by peatland drainage

    NASA Astrophysics Data System (ADS)

    Marttila, H.; Tammela, S.; Kløve, B.

    2009-04-01

    Peatland drainage for forestry, agriculture, peat harvesting and urban infrastructure has been altered landscape in Finland. Pristine peatlands and headwaters provide important hydrological and ecological functions that can be lost after drainage. The drainage has resulted in increase of forest resources but also negative environmental effects including changes in runoffs, erosion processes, siltation and eutrophication. The changes that can occur after drainage are, however, complex and must be better understood if the negative impacts of drainage are to be reduced or prevented. Especially erosion and transport processes of organic peat sediment are not well understood (Marttila and Kløve, 2008). Methods for controlling the sediment load include erosion and transport control practices in the catchment area (Marttila and Kløve, 2009; Tammela et al. 2009). The presentation/poster will present methods and preliminary results project from Northern Finland. The issues especially covered are sediment erosion and transport and methods to restore and reduce impacts of peatland drainage in boreal headwaters. Keywords: sediment transport, erosion, peatland drainage, organic and inorganic sediment, stream and catchment restoration, management, environment References: Marttila, H. and Kløve. B. 2008. Erosion and delivery of deposited peat sediment. Water Resources Research. 44 (6). Marttila, H. Kløve. B. 2009. Retention of sediment and nutrient loads with peak runoff control. Journal of Irrigation and Drainage Engineering (in press). Tammela, S. Marttila, H. and Kløve. B. 2009. Effect and design of an underminer structure on flow distribution and local bed topography (submitted).

  18. Drainage ditches facilitate frog movements in a hostile landscape

    USGS Publications Warehouse

    Mazerolle, M.J.

    2005-01-01

    Ditches are common in landscapes influenced by agricultural, forestry, and peat mining activities, and their value as corridors remains unassessed. Pond-breeding amphibians can encounter hostile environments when moving between breeding, summering, or hibernation sites, and are likely to benefit from the presence of ditches in the landscape. Within a system consisting of ditch networks in bogs mined for peat in eastern New Brunswick, Canada, I quantified the breeding, survival, and movements of green frogs (Rana clamitans melanota) in drainage ditches and also surveyed peat fields. Frogs rarely ventured on peat fields and most individuals frequented drainage ditches containing water, particularly in late summer. Though frogs did not breed in ditches, their survival rate in ditches was high (88%). Ditches did not hinder frog movements, as frogs moved independently of the current. Results indicate that drainage ditches containing water enable some movements between habitats isolated by peat mining, in contrast to peat surfaces, and suggest they function as amphibian movement corridors. Thus, such drainage ditches may mitigate the effects of peat extraction on amphibian populations. At the very least, these structures provide an alternative to hostile peat surfaces. This study highlights that small-scale corridors are potentially valuable in population dynamics. ?? Springer 2005.

  19. Models Robustness for Simulating Drainage and NO3-N Fluxes

    NASA Astrophysics Data System (ADS)

    Jabro, Jay; Jabro, Ann

    2013-04-01

    Computer models simulate and forecast appropriate agricultural practices to reduce environmental impact. The objectives of this study were to assess and compare robustness and performance of three models -- LEACHM, NCSWAP, and SOIL-SOILN--for simulating drainage and NO3-N leaching fluxes in an intense pasture system without recalibration. A 3-yr study was conducted on a Hagerstown silt loam to measure drainage and NO3-N fluxes below 1 m depth from N-fertilized orchardgrass using intact core lysimeters. Five N-fertilizer treatments were replicated five times in a randomized complete block experimental design. The models were validated under orchardgrass using soil, water and N transformation rate parameters and C pools fractionation derived from a previous study conducted on similar soils under corn. The model efficiency (MEF) of drainage and NO3-N fluxes were 0.53, 0.69 for LEACHM; 0.75, 0.39 for NCSWAP; and 0.94, 0.91for SOIL-SOILN. The models failed to produce reasonable simulations of drainage and NO3-N fluxes in January, February and March due to limited water movement associated with frozen soil and snow accumulation and melt. The differences between simulated and measured NO3-N leaching and among models' performances may also be related to soil N and C transformation processes embedded in the models These results are a monumental progression in the validation of computer models which will lead to continued diffusion across diverse stakeholders.

  20. Direct cholangiography and biliary drainage.

    PubMed

    Burcharth, F; Kruse, A

    1996-01-01

    Direct cholangiography by percutaneous transhepatic cholangiography or endoscopic retrograde cholangiography has greatly improved diagnostic work-up of patients with known or suspected biliary obstruction. These diagnostic procedures were introduced in Denmark in the early 1970s, and technical refinements and clinical research of the methods were initiated. The Danish contribution led to definition of indications for direct cholangiography and general acceptance of the methods in daily clinical practice; nationally as well as internationally. The transhepatic cholangiography with selective catheterization of the biliary ducts permitted external drainage of obstructed ducts. The disadvantages of this technique inspired the innovation of internal biliary drainage and the invention of the biliary endoprosthesis. The endoscopic approach to the biliary tract and the technical improvements of accessory instruments led to the early introduction of therapeutic procedures, i.e. papillotomy, stone removal, biliary drainage and treatment of strictures and post-traumatic lesions. Experimental and clinical research with endoprostheses improved their function and prevented dislodgment. Clinical research documented that biliary drainage by endoprosthesis is a valuable alternative to surgical bypass in patients with inoperable biliary obstructions. Endoscopic therapeutic procedures for common bile duct stones have almost replaced conventional surgical treatment. Endoluminal imaging techniques are under evaluation and may contribute to future improvements.

  1. Tangible Exploration of Subsurface Data

    NASA Astrophysics Data System (ADS)

    Petrasova, A.; Harmon, B.; Mitasova, H.; White, J.

    2014-12-01

    Since traditional subsurface visualizations using 2D maps, profiles or charts can be difficult to interpret and often do not convey information in an engaging form, scientists are interested in developing alternative visualization techniques which would help them communicate the subsurface volume data with students and general public. We would like to present new technique for interactive visualization of subsurface using Tangible geospatial modeling and visualization system (Tangeoms). It couples a physical, three-dimensional model with geospatial modeling and analysis through a cycle of scanning and projection. Previous applications of Tangeoms were exploring the impact of terrain modifications on surface-based geophysical processes, such as overland water flow, sediment transport, and also on viewsheds, cast shadows or solar energy potential. However, Tangeoms can serve as a tool for exploring subsurface as well. By creating a physical sand model of a study area, removing the sand from different parts of the model and projecting the computed cross-sections, we can look under the ground as if we were at an excavation site, and see the actual data represented as a 3D raster in that particular part of the model. Depending on data availability, we can also incorporate temporal dimension. Our method is an intuitive and natural way of exploring subsurface data and for users, it represents an alternative to more abstract 3D computer visualization tools, by offering direct, tangible interface.

  2. Endoscopic subsurface imaging in tissues

    SciTech Connect

    Demos, S G; Staggs, M; Radousky, H B

    2001-02-12

    The objective of this work is to develop endoscopic subsurface optical imaging technology that will be able to image different tissue components located underneath the surface of the tissue at an imaging depth of up to 1 centimeter. This effort is based on the utilization of existing technology and components developed for medical endoscopes with the incorporation of the appropriate modifications to implement the spectral and polarization difference imaging technique. This subsurface imaging technique employs polarization and spectral light discrimination in combination with image processing to remove a large portion of the image information from the outer layers of the tissue which leads to enhancement of the contrast and image quality of subsurface tissue structures.

  3. Measuring isotropic subsurface light transport.

    PubMed

    Happel, Kathrin; Dörsam, Edgar; Urban, Philipp

    2014-04-21

    Subsurface light transport can affect the visual appearance of materials significantly. Measuring and modeling this phenomenon is crucial for accurately reproducing colors in printing or for rendering translucent objects on displays. In this paper, we propose an apparatus to measure subsurface light transport employing a reference material to cancel out adverse signals that may bias the results. In contrast to other approaches, the setup enables improved focusing on rough surfaces (e.g. uncoated paper). We derive a measurement equation that may be used to deduce the point spread function (PSF) of subsurface light transport. Main contributions are the usage of spectrally-narrowband exchangeable LEDs allowing spectrally-resolved measurements and an approach based on quadratic programming for reconstructing PSFs in the case of isotropic light transport.

  4. Subsurface microbial habitats on Mars

    NASA Technical Reports Server (NTRS)

    Boston, P. J.; Mckay, C. P.

    1991-01-01

    We developed scenarios for shallow and deep subsurface cryptic niches for microbial life on Mars. Such habitats could have considerably prolonged the persistence of life on Mars as surface conditions became increasingly inhospitable. The scenarios rely on geothermal hot spots existing below the near or deep subsurface of Mars. Recent advances in the comparatively new field of deep subsurface microbiology have revealed previously unsuspected rich aerobic and anaerobic microbal communities far below the surface of the Earth. Such habitats, protected from the grim surface conditions on Mars, could receive warmth from below and maintain water in its liquid state. In addition, geothermally or volcanically reduced gases percolating from below through a microbiologically active zone could provide the reducing power needed for a closed or semi-closed microbial ecosystem to thrive.

  5. Drainage-Area Data for Wisconsin Streams

    DTIC Science & Technology

    1983-01-01

    drainage areas for gaging stations, sewage-treatment plants, dams , major highway crossings, and other sites where discharge measurements or water-quality...streams of 10 mil or more . Also, areas have been determined for sewage-treatment plants, dams , major highway crossings, gaging stations, and other...plants, ma- jor highway crossings, dam , and powerplants . Drainage Area The column under the drainage-area heading lists the drainage-area of the site

  6. Drainage-area data for Wisconsin streams

    USGS Publications Warehouse

    Henrich, E.W.; Daniel, D.N.

    1983-01-01

    Drainage areas were delineated on U.S. Geological Survey topographic maps. Drainage areas are shown in tabular form under six headings : station number; stream name, rank, and location; township, range, and section ; county; type of site; and drainage area. Eleven major-river-basin maps show the location and station number of key sites .

  7. Mine Drainage Control and Treatment Options

    EPA Science Inventory

    This presentation is the third in a series of webinars for Region 10's Hardrock Mine Geochemistry and Hydrology Webinar Workshops. It will discuss briefly how mine drainage forms, some suggested mitigation methods, how ions in the drainage change if drainage does get to the envi...

  8. Towed Subsurface Optical Communications Buoy

    NASA Technical Reports Server (NTRS)

    Stirbl, Robert C.; Farr, William H.

    2013-01-01

    The innovation allows critical, high-bandwidth submarine communications at speed and depth. This reported innovation is a subsurface optical communications buoy, with active neutral buoyancy and streamlined flow surface veins for depth control. This novel subsurface positioning for the towed communications buoy enables substantial reduction in water-absorption and increased optical transmission by eliminating the intervening water absorption and dispersion, as well as by reducing or eliminating the beam spread and the pulse spreading that is associated with submarine-launched optical beams.

  9. Attributes for NHDPlus Catchments (Version 1.1) in the Conterminous United States: Artificial Drainage (1992) and Irrigation Types (1997)

    USGS Publications Warehouse

    Wieczorek, Michael; LaMotte, Andrew E.

    2010-01-01

    This tabular dataset represents the estimated area of artificial drainage for the year 1992 and irrigation types for the year 1997 compiled for every catchment of NHDPlus for the conterminous United States. The source datasets were derived from tabular National Resource Inventory (NRI) datasets created by the National Resources Conservation Service (NRCS, U.S. Department of Agriculture, 1995, 1997). Artificial drainage is defined as subsurface drains and ditches. Irrigation types are defined as gravity and pressure. Subsurface drains are described as conduits, such as corrugated plastic tubing, tile, or pipe, installed beneath the ground surface to collect and/or convey drainage. Surface drainage field ditches are described as graded ditches for collecting excess water. Gravity irrigation source is described as irrigation delivered to the farm and/or field by canals or pipelines open to the atmosphere; and water is distributed by the force of gravity down the field by: (1) A surface irrigation system (border, basin, furrow, corrugation, wild flooding, etc.) or (2) Sub-surface irrigation pipelines or ditches. Pressure irrigation source is described as irrigation delivered to the farm and/or field in pump or elevation-induced pressure pipelines, and water is distributed across the field by: (1) Sprinkle irrigation (center pivot, linear move, traveling gun, side roll, hand move, big gun, or fixed set sprinklers), or (2) Micro irrigation (drip emitters, continuous tube bubblers, micro spray or micro sprinklers). NRI data do not include Federal lands and are thus excluded from this dataset. The tabular data for drainage were spatially apportioned to the National Land Cover Dataset (NLCD, Kerie Hitt, written commun., 2005) and the tabular data for irrigation were spatially apportioned to an enhanced version of the National Land Cover Dataset (NLCDe, Nakagaki and others 2007) The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that

  10. Agriculture: Newsroom

    EPA Pesticide Factsheets

    Agriculture Newsroom. News releases, reports, and other documents from around EPA that are of interest or direct importance to the environmental management or compliance efforts of the agricultural community.

  11. Grassland agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture in grassland environments is facing multiple stresses from: shifting demographics, declining and fragmented agricultural landscapes, declining environmental quality, variable and changing climate, volatile and increasing energy costs, marginal economic returns, and globalization. Degrad...

  12. SUBSURFACE VISUAL ALARM SYSTEM ANALYSIS

    SciTech Connect

    D.W. Markman

    2001-08-06

    The ''Subsurface Fire Hazard Analysis'' (CRWMS M&O 1998, page 61), and the document, ''Title III Evaluation Report for the Surface and Subsurface Communication System'', (CRWMS M&O 1999a, pages 21 and 23), both indicate the installed communication system is adequate to support Exploratory Studies Facility (ESF) activities with the exception of the mine phone system for emergency notification purposes. They recommend the installation of a visual alarm system to supplement the page/party phone system The purpose of this analysis is to identify data communication highway design approaches, and provide justification for the selected or recommended alternatives for the data communication of the subsurface visual alarm system. This analysis is being prepared to document a basis for the design selection of the data communication method. This analysis will briefly describe existing data or voice communication or monitoring systems within the ESF, and look at how these may be revised or adapted to support the needed data highway of the subsurface visual alarm. system. The existing PLC communication system installed in subsurface is providing data communication for alcove No.5 ventilation fans, south portal ventilation fans, bulkhead doors and generator monitoring system. It is given that the data communication of the subsurface visual alarm system will be a digital based system. It is also given that it is most feasible to take advantage of existing systems and equipment and not consider an entirely new data communication system design and installation. The scope and primary objectives of this analysis are to: (1) Briefly review and describe existing available data communication highways or systems within the ESF. (2) Examine technical characteristics of an existing system to disqualify a design alternative is paramount in minimizing the number of and depth of a system review. (3) Apply general engineering design practices or criteria such as relative cost, and degree of

  13. Femtosecond laser subsurface scleral treatment in cadaver human sclera and evaluation using two-photon and confocal microscopy

    NASA Astrophysics Data System (ADS)

    Sun, Hui; Fan, Zhongwei; Yan, Ying; Lian, Fuqiang; Kurtz, Ron; Juhasz, Tibor

    2016-03-01

    Glaucoma is the second-leading cause of blindness worldwide and is often associated with elevated intraocular pressure (IOP). Partial-thickness drainage channels can be created with femtosecond laser in the translucent sclera for the potential treatment of glaucoma. We demonstrate the creation of partial-thickness subsurface drainage channels with the femtosecond laser in the cadaver human eyeballs and describe the application of two-photon microscopy and confocal microscopy for noninvasive imaging of the femtosecond laser created partial-thickness scleral channels in cadaver human eyes. A femtosecond laser operating at a wavelength of 1700 nm was scanned along a rectangular raster pattern to create the partial thickness subsurface drainage channels in the sclera of cadaver human eyes. Analysis of the dimensions and location of these channels is important in understanding their effects. We describe the application of two-photon microscopy and confocal microscopy for noninvasive imaging of the femtosecond laser created partial-thickness scleral channels in cadaver human eyes. High-resolution images, hundreds of microns deep in the sclera, were obtained to allow determination of the shape and dimension of such partial thickness subsurface scleral channels. Our studies suggest that the confocal and two-photon microscopy can be used to investigate femtosecond-laser created partial-thickness drainage channels in the sclera of cadaver human eyes.

  14. Drainage Areas of Selected Streams in Virginia

    USGS Publications Warehouse

    Hayes, Donald C.; Wiegand, Ute

    2006-01-01

    Drainage areas were determined for more than 1,600 basins in the three major river basins of Virginia -- the North Atlantic Slope, South Atlantic Slope, and Ohio River Basins. Drainage areas range from 0.004 square mile to 7,866 square miles. A geographic information system was used to digitize and store data associated with the drainage basins. Drainage divides were digitized from digital U.S. Geological Survey 7.5-minute, 1:24,000-scale, topographic quadrangles using procedures recommended by the Subcommittee on Hydrology, Federal Interagency River Basin Committee. Digital drainage basins were quality assured, polygons of the closed drainage basins were generated, and drainage areas were computed.

  15. Investigating summer flow paths in a Dutch agricultural field using high frequency direct measurements

    NASA Astrophysics Data System (ADS)

    Delsman, J. R.; Waterloo, M. J.; Groen, M. M. A.; Groen, J.; Stuyfzand, P. J.

    2014-11-01

    The search for management strategies to cope with projected water scarcity and water quality deterioration calls for a better understanding of the complex interaction between groundwater and surface water in agricultural catchments. We separately measured flow routes to tile drains and an agricultural ditch in a deep polder in the coastal region of the Netherlands, characterized by exfiltration of brackish regional groundwater flow and intake of diverted river water for irrigation and water quality improvement purposes. We simultaneously measured discharge, electrical conductivity and temperature of these separate flow routes at hourly frequencies, disclosing the complex and time-varying patterns and origins of tile drain and ditch exfiltration. Tile drainage could be characterized as a shallow flow system, showing a non-linear response to groundwater level changes. Tile drainage was fed primarily by meteoric water, but still transported the majority (80%) of groundwater-derived salt to surface water. In contrast, deep brackish groundwater exfiltrating directly in the ditch responded linearly to groundwater level variations and is part of a regional groundwater flow system. We could explain the observed salinity of exfiltrating drain and ditch water from the interaction between the fast-responding pressure distribution in the subsurface that determined groundwater flow paths (wave celerity), and the slow-responding groundwater salinity distribution (water velocity). We found water demand for maintaining water levels and diluting salinity through flushing to greatly exceed the actual sprinkling demand. Counterintuitively, flushing demand was found to be largest during precipitation events, suggesting the possibility of water savings by operational flushing control.

  16. Subsurface Electromagnetic Target Characterization and Identification

    DTIC Science & Technology

    1979-06-01

    B. Subsurface Electromagnetic Video Pulse Radar System 5 C. The Subsurface Targets 11 D. Raw Measured Waveforms 14 E. Processed Waveforms 15 III...259 r i. I .. . . .... .. . . . . .;. . . . .. .. o _ • v . . • • • -• -. . .. -"... .. . II II LIST OF FIGURES Figure Page 1 The subsurface pulse ...7 3 Typical raw waveform received by the pulse radar system ..... ................... .i..... 9 4 Physical characteristics of the subsurface

  17. Global 30m Height Above the Nearest Drainage

    NASA Astrophysics Data System (ADS)

    Donchyts, Gennadii; Winsemius, Hessel; Schellekens, Jaap; Erickson, Tyler; Gao, Hongkai; Savenije, Hubert; van de Giesen, Nick

    2016-04-01

    Variability of the Earth surface is the primary characteristics affecting the flow of surface and subsurface water. Digital elevation models, usually represented as height maps above some well-defined vertical datum, are used a lot to compute hydrologic parameters such as local flow directions, drainage area, drainage network pattern, and many others. Usually, it requires a significant effort to derive these parameters at a global scale. One hydrological characteristic introduced in the last decade is Height Above the Nearest Drainage (HAND): a digital elevation model normalized using nearest drainage. This parameter has been shown to be useful for many hydrological and more general purpose applications, such as landscape hazard mapping, landform classification, remote sensing and rainfall-runoff modeling. One of the essential characteristics of HAND is its ability to capture heterogeneities in local environments, difficult to measure or model otherwise. While many applications of HAND were published in the academic literature, no studies analyze its variability on a global scale, especially, using higher resolution DEMs, such as the new, one arc-second (approximately 30m) resolution version of SRTM. In this work, we will present the first global version of HAND computed using a mosaic of two DEMS: 30m SRTM and Viewfinderpanorama DEM (90m). The lower resolution DEM was used to cover latitudes above 60 degrees north and below 56 degrees south where SRTM is not available. We compute HAND using the unmodified version of the input DEMs to ensure consistency with the original elevation model. We have parallelized processing by generating a homogenized, equal-area version of HydroBASINS catchments. The resulting catchment boundaries were used to perform processing using 30m resolution DEM. To compute HAND, a new version of D8 local drainage directions as well as flow accumulation were calculated. The latter was used to estimate river head by incorporating fixed and

  18. Optimal Allocation of Maximum Allowable Discharged Total Nitrogen Load among Field Plots in Agricultural Watershed

    NASA Astrophysics Data System (ADS)

    Maeda, Shigeya; Yoshikawa, Kazuki; Takeuchi, Junichiro; Kawachi, Toshihiko; Chono, Shunsuke; Unami, Koichi

    A multiobjective optimization model is developed for controlling TN (Total Nitrogen) load discharged from field plots in an agricultural watershed. In optimization, maximizations of allowable TN discharge per unit area and total yield of rice are intended while complying with an effluent limitation standard prescribed for river water quality management. The discharge from a field plot is separated into two components, i.e., direct runoff and baseflow. As discharged TN from a plot travels with these components toward an outlet of the watershed, the amount of TN is assumed to decrease due to distance-related self-purification occurring in subsurface zone, drainage canal and river. Locations of field plots and traveling routes of TN are identified or predicted by a GIS (Geographic Information System) with a digital elevation model and by field surveys. The model developed is applied to an agricultural watershed bordering with Lake Biwa in Shiga Prefecture, Japan. The result demonstrates that the optimal allocation of maximum allowable discharged TN load among field plots is helpful in prioritizing plots where fertilization should be reduced.

  19. Transport of agricultural contaminants through karst soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Karst landscapes are common in many agricultural regions in the US. Well-developed karst landscapes are characterized by shallow soils, sinkholes, sinking streams, underground conduits, and springs. In these landscapes surface runoff is minimal and most recharge enters the subsurface relatively quic...

  20. Storm water management: Potential for lower cost & more benefits if farmers & municipalities cooperate on tile drainage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A common approach to protect communities from the ravages of stream flooding is to construct storm water retention basins upstream from the property to be protected. Retention basins are an expensive solution and often take valuable agricultural land out of production. Improved drainage of agricultu...

  1. Phosphorus losses from drainage systems: breaking the surface tile riser connection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In freshwater ecosystems, phosphorus is generally the nutrient most limiting algal growth. Agricultural drainage systems in the upper Midwestern US are generally designed to drain water as quickly as possible, in order to ensure trafficability and minimize crop damage due to flooding. An unintended ...

  2. Nutrient mass balance for the Albemarle-Pamlico Drainage Basin, North Carolina and Virginia, 1990

    USGS Publications Warehouse

    McMahon, G.; Woodside, M.D.

    1997-01-01

    A 1990 nitrogen and phosphorus mass balance calculated for eight National Stream Quality Accounting Network (NASQAN) basins in the Albemarle-Pamlico Drainage Basin indicated the importance of agricultural nonpoint sources of nitrogen and phosphorus and watershed nitrogen retention and processing capabilities. Basin total nitrogen and phosphorus input estimates were calculated for atmospheric deposition (which averaged 27 percent of total nitrogen inputs and 22 percent of total phosphorus inputs); crop fertilizer (27 and 25 percent); animal-waste (22 and 50 percent, respectively); point sources (3 percent each of total nitrogen and total phosphorus inputs); and biological nitrogen fixation (21 percent of total nitrogen inputs). Highest in-stream nitrogen and phosphorus loads were measured in predominantly agricultural drainage areas. Intermediate loads were observed in mixed agricultural/urban drainage areas; the lowest loads were measured in mixed agricultural/forested drainage areas. The difference between the sum of the nutrient input categories and the sum of the instream nutrient loads and crop-harvest nutrient removal was assigned to a residual category for the basin. The residual category averaged 51 percent of total nitrogen inputs and 54 percent of total phosphorus inputs.

  3. Crop yield summary for three wetland reservoir subirrigation systems in northwest Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wetland Reservoir Subirrigation Systems (WRSIS) are innovative agricultural water management and recycling systems comprised of three main components; a constructed wetland, a water storage reservoir, and cropland containing subsurface drainage pipe systems. Surface runoff and subsurface drainage f...

  4. Full-waveform modeling of Zero-Offset Electromagnetic Induction for Accurate Characterization of Subsurface Electrical Properties

    NASA Astrophysics Data System (ADS)

    Moghadas, D.; André, F.; Vereecken, H.; Lambot, S.

    2009-04-01

    Water is a vital resource for human needs, agriculture, sanitation and industrial supply. The knowledge of soil water dynamics and solute transport is essential in agricultural and environmental engineering as it controls plant growth, hydrological processes, and the contamination of surface and subsurface water. Increased irrigation efficiency has also an important role for water conservation, reducing drainage and mitigating some of the water pollution and soil salinity. Geophysical methods are effective techniques for monitoring the vadose zone. In particular, electromagnetic induction (EMI) can provide in a non-invasive way important information about the soil electrical properties at the field scale, which are mainly correlated to important variables such as soil water content, salinity, and texture. EMI is based on the radiation of a VLF EM wave into the soil. Depending on its electrical conductivity, Foucault currents are generated and produce a secondary EM field which is then recorded by the EMI system. Advanced techniques for EMI data interpretation resort to inverse modeling. Yet, a major gap in current knowledge is the limited accuracy of the forward model used for describing the EMI-subsurface system, usually relying on strongly simplifying assumptions. We present a new low frequency EMI method based on Vector Network Analyzer (VNA) technology and advanced forward modeling using a linear system of complex transfer functions for describing the EMI loop antenna and a three-dimensional solution of Maxwell's equations for wave propagation in multilayered media. VNA permits simple, international standard calibration of the EMI system. We derived a Green's function for the zero-offset, off-ground horizontal loop antenna and also proposed an optimal integration path for faster evaluation of the spatial-domain Green's function from its spectral counterpart. This new integration path shows fewer oscillations compared with the real path and permits to avoid the

  5. Drainage area data for Alabama streams

    USGS Publications Warehouse

    Stallings, J.S.; Peirce, L.B.

    1957-01-01

    The drainage area of a river basin is an important parameter in many engineering equations used for hydrologic design. It is not a parameter, however, that always requires precise measurement. Factors in the hydrologic cycle such as rainfall, runoff, transpiration, and infiltration cannot be measured nearly as closely as drainage area. Largely for this reason, drainage areas are often measured to varying degrees of precision depending upon the immediate need, with little thought to some other use or some other user of the figure obtained. It can readily be appreciated that this practice, continued for long by many different agencies, will result in a heterogeneous collection of drainage area figures, often discordant and of an accuracy unknown to any but those who computed them. Figures of drainage area published by various Federal agencies are frequently discrepant or contradictory, giving rise to confusion in the use of drainage area data. Seeking to better this situation, the Federal Inter-Agency River Basin Committee (FIARBC) in November 1951 published its Bulletin No. 4, Inter-Agency Coordination of Drainage Area Data. That Bulletin recommended procedures to be followed by the interested Federal agencies “for coordinating drainage area data in the interest of promoting uniformity, reducing confusion and contradiction of published figures, and improving the ready availability of drainage area data pertaining to drainage basins of the United States and its possessions.”

  6. Method of installing subsurface barrier

    SciTech Connect

    Nickelson, Reva A.; Richardson, John G.; Kostelnik, Kevin M.; Sloan, Paul A.

    2007-10-09

    Systems, components, and methods relating to subterranean containment barriers. Laterally adjacent tubular casings having male interlock structures and multiple female interlock structures defining recesses for receiving a male interlock structure are used to create subterranean barriers for containing and treating buried waste and its effluents. The multiple female interlock structures enable the barriers to be varied around subsurface objects and to form barrier sidewalls. The barrier may be used for treating and monitoring a zone of interest.

  7. Nitrate-Nitrogen Leaching and Modeling in Intensive Agriculture Farmland in China

    PubMed Central

    Xu, Ligang; Xu, Jin

    2013-01-01

    Protecting water resources from nitrate-nitrogen (NO3-N) contamination is an important public health concern and a major national environmental issue in China. Loss of NO3-N in soils due to leaching is not only one of the most important problems in agriculture farming, but is also the main factor causing nitrogen pollution in aquatic environments. Three typical intensive agriculture farmlands in Jiangyin City in China are selected as a case study for NO3-N leaching and modeling in the soil profile. In this study, the transport and fate of NO3-N within the soil profile and nitrate leaching to drains were analyzed by comparing field data with the simulation results of the LEACHM model. Comparisons between measured and simulated data indicated that the NO3-N concentrations in the soil and nitrate leaching to drains are controlled by the fertilizer practice, the initial conditions and the rainfall depth and distribution. Moreover, the study reveals that the LEACHM model gives a fair description of the NO3-N dynamics in the soil and subsurface drainage at the field scale. It can also be concluded that the model after calibration is a useful tool to optimize as a function of the combination “climate-crop-soil-bottom boundary condition” the nitrogen application strategy resulting for the environment in an acceptable level of nitrate leaching. The findings in this paper help to demonstrate the distribution and migration of nitrogen in intensive agriculture farmlands, as well as to explore the mechanism of groundwater contamination resulting from agricultural activities. PMID:23983629

  8. Hydrologic control of dissolved organic matter concentration and quality in a semiarid artificially drained agricultural catchment

    NASA Astrophysics Data System (ADS)

    Bellmore, Rebecca A.; Harrison, John A.; Needoba, Joseph A.; Brooks, Erin S.; Kent Keller, C.

    2015-10-01

    Agricultural practices have altered watershed-scale dissolved organic matter (DOM) dynamics, including in-stream concentration, biodegradability, and total catchment export. However, mechanisms responsible for these changes are not clear, and field-scale processes are rarely directly linked to the magnitude and quality of DOM that is transported to surface water. In a small (12 ha) agricultural catchment in eastern Washington State, we tested the hypothesis that hydrologic connectivity in a catchment is the dominant control over the concentration and quality of DOM exported to surface water via artificial subsurface drainage. Concentrations of dissolved organic carbon (DOC) and humic-like components of DOM decreased while the Fluorescence Index and Freshness Index increased with depth through the soil profile. In drain discharge, these characteristics were significantly correlated with drain flow across seasons and years, with drain DOM resembling deep sources during low-flow and shallow sources during high flow, suggesting that DOM from shallow sources bypasses removal processes when hydrologic connectivity in the catchment is greatest. Assuming changes in streamflow projected for the Palouse River (which contains the study catchment) under the A1B climate scenario (rapid growth, dependence on fossil fuel, and renewable energy sources) apply to the study catchment, we project greater interannual variability in annual DOC export in the future, with significant increases in the driest years. This study highlights the variability in DOM inputs from agricultural soil to surface water on daily to interannual time scales, pointing to the need for a more nuanced understanding of agricultural impacts on DOM dynamics in surface water.

  9. INL Subsurface Wireless Sensor Platform

    SciTech Connect

    Dennis C. Kunerth; John M. Svoboda; James T. Johnson

    2005-10-01

    The Idaho National Laboratory is developing a versatile micro-power sensor interface platform for periodic subsurface sensing of environmental variables important to waste disposal sites such as volumetric moisture, water potential, and temperature. The key characteristics of the platform architecture are that the platform is passive until externally energized --no internal power source is required -- and that it communicates with a "reader" via short-range telemetry - no wires penetrate the subsurface. Other significant attributes include the potential for a long service life and a compact size that makes it well suited for retrofitting existing landfill structures. Functionally, the sensor package is "read" by a short-range induction coil that activates and powers the sensor platform as well as detects the sensor output via a radio frequency signal generated by the onboard programmable interface controller microchip. As a result, the platform has a functional subsurface communication range of approximately 10 to 12 ft. and can only accept sensors that require low power to operate.

  10. SUBSURFACE RESIDENCE TIMES AS AN ALGORITHM FOR AQUIFER SENSITIVITY MAPPING: TESTING THE CONCEPT WITH GROUND WATER MODELS IN THE CONTENTNEA CREEK BASIN, NORTH CAROLINA, USA

    EPA Science Inventory

    This poster will present a modeling and mapping assessment of landscape sensitivity to non-point source pollution as applied to a hierarchy of catchment drainages in the Coastal Plain of the state of North Carolina. Analysis of the subsurface residence time of water in shallow a...

  11. Corn yield and nitrate loss in subsurface drainage affected by timing of anhydrous ammonia application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surprisingly little research has examined the corn yield, N use efficiency, and water quality implications of N fertilizer timing. We applied anhydrous ammonia either in the fall after harvest (F) at 196 kg ha-1, or in the spring before planting (PP) or as an early sidedress (SD) at rates of 168 kg ...

  12. Assessment of Subsurface Drainage Management Practices to Reduce Nitrogen Loadings Using AnnAGNPS

    EPA Science Inventory

    The goal of the Future Midwest Landscape project is to quantify current and future landscape services across the region and examine changes expected to occur as a result of two alternative drivers of future change: the growing demand for biofuels; and hypothetical increases in in...

  13. Assessment of Subsurface Drainage and Fertilizer Management Practices to Reduce Nutrient Loadings using AnnAGNPS

    EPA Science Inventory

    The Future Midwest Landscape (FML) project is part of the US Environmental Protection Agency (EPA)’s new Ecological Service Research Program (ESRP), undertaken to examine the variety of ways in which landscapes that include crop lands, conservation areas, wetlands, lakes, and str...

  14. Nitrate loss in subsurface drainage and corn yield as affected by timing of sidedress nitrogen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using chlorophyll meters, crop sensors, or aerial photography to fine-tune sidedress N application rates have been proposed for optimizing and perhaps reducing overall N fertilizer use on corn (Zea mays L.) and thereby improving water quality by reducing NO3 losses to surface and ground waters. Howe...

  15. Drainage in a rising foam.

    PubMed

    Yazhgur, Pavel; Rio, Emmanuelle; Rouyer, Florence; Pigeonneau, Franck; Salonen, Anniina

    2016-01-21

    Rising foams created by continuously blowing gas into a surfactant solution are widely used in many technical processes, such as flotation. The prediction of the liquid fraction profile in such flowing foams is of particular importance since this parameter controls the stability and the rheology of the final product. Using drift flux analysis and recently developed semi-empirical expressions for foam permeability and osmotic pressure, we build a model predicting the liquid fraction profile as a function of height. The theoretical profiles are very different if the interfaces are considered as mobile or rigid, but all of our experimental profiles are described by the model with mobile interfaces. Even the systems with dodecanol are well known to behave as rigid in forced drainage experiments. This is because in rising foams the liquid fraction profile is fixed by the flux at the bottom of the foam. Here the foam is wet with higher permeability and the interfaces are not in equilibrium. These results demonstrate once again that it is not only the surfactant system that controls the mobility of the interface, but also the hydrodynamic problem under consideration. For example liquid flow through the foam during generation or in forced drainage is intrinsically different.

  16. Fluid Drainage from Porous Reservoirs

    NASA Astrophysics Data System (ADS)

    Zheng, Zhong; Soh, Beatrice; Huppert, Herbert; Stone, Howard; Stone Group Team

    2012-11-01

    We report theoretical and experimental studies to describe buoyancy-driven fluid drainage from a porous medium. We first study homogeneous porous systems. To investigate the influence of heterogeneities, we consider the case where the permeability varies transverse to the flow direction, exemplified by a V-shaped Hele-Shaw cell. Finally, we analyze a model where both the permeability and the porosity vary transverse to the flow direction. In each case, a self-similar solution for the shape of the gravity current is found and a power-law behavior in time is derived for the mass remaining in the system. Laboratory experiments are conducted in homogeneous and V-shaped Hele-Shaw cells, and the measured profile shapes and the mass remaining in the cells agree well with our model predictions. Our study provides new insights into drainage processes such as may occur in a variety of natural and industrial activities including the geological storage of carbon dioxide. This work is supported by a grant from Carbon Mitigation Initiative at Princeton University.

  17. [Lung cancer and lymph drainage].

    PubMed

    Riquet, M

    2007-01-01

    Lung cancer is lymphophile and may involve lymph nodes (LN) belonging to lung lymph drainage. LN metastases are figured within stations numbered 1 to 14. These stations are located along lymph vessels. The lymph vessels and the LN are forming together anatomical chains. Lymph vessels are valved and pulsatile and travel to the cervical venous confluence where they pour the lung lymph into the blood circulation. They may be totally or partly nodeless along their travel, anastomose with each other around the trachea, and connect with the thoracic duct within the mediastinum. Within the anatomical LN chains, LN are variable in number and in size from one individual to another. They may be absent from one or several stations of the international mapping. Stations are located along the anatomical chains: pulmonary ligament (9), tracheal bifurcation(8 and 7), right paratracheal (4R, 2R and 1), preaortic (5 and 6), left paratracheal (4L, 2L and 1). Station 3 is located on 2 differents chains (phrenic and right esophagotracheal). Station 10 are located at the beginning of the mediastinal lymph nodes chains. Each chain connects with the blood circulation, anastomoses with he neighbouring chains and behave as an own entity whatever the number of its LN. International station mapping misknowns this anatomy and occults the true pronostic value of lung lymph drainage.

  18. Effect of nitrogen application timing on corn production using subsurface drip irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The utilization of subsurface drip irrigation (SDI) in row-crop agriculture is increasing due to potential increases in water and nutrient use efficiency. Research-based information is needed to manage nitrogen (N) applications through SDI systems in field corn (Zea mays L.) production. This study ...

  19. Review of Constructed Subsurface Flow vs. Surface Flow Wetlands

    SciTech Connect

    HALVERSON, NANCY

    2004-09-01

    The purpose of this document is to use existing documentation to review the effectiveness of subsurface flow and surface flow constructed wetlands in treating wastewater and to demonstrate the viability of treating effluent from Savannah River Site outfalls H-02 and H-04 with a subsurface flow constructed wetland to lower copper, lead and zinc concentrations to within National Pollutant Discharge Elimination System (NPDES) Permit limits. Constructed treatment wetlands are engineered systems that have been designed and constructed to use the natural functions of wetlands for wastewater treatment. Constructed wetlands have significantly lower total lifetime costs and often lower capital costs than conventional treatment systems. The two main types of constructed wetlands are surface flow and subsurface flow. In surface flow constructed wetlands, water flows above ground. Subsurface flow constructed wetlands are designed to keep the water level below the top of the rock or gravel media, thus minimizing human and ecological exposure. Subsurface flow wetlands demonstrate higher rates of contaminant removal per unit of land than surface flow (free water surface) wetlands, therefore subsurface flow wetlands can be smaller while achieving the same level of contaminant removal. Wetlands remove metals using a variety of processes including filtration of solids, sorption onto organic matter, oxidation and hydrolysis, formation of carbonates, formation of insoluble sulfides, binding to iron and manganese oxides, reduction to immobile forms by bacterial activity, and uptake by plants and bacteria. Metal removal rates in both subsurface flow and surface flow wetlands can be high, but can vary greatly depending upon the influent concentrations and the mass loading rate. Removal rates of greater than 90 per cent for copper, lead and zinc have been demonstrated in operating surface flow and subsurface flow wetlands. The constituents that exceed NPDES limits at outfalls H-02 a nd H

  20. Subsurface Residence Times as an Algorithm for Aquifer Sensitivity Mapping: testing the concept with analytic element ground water models in the Contentnea Creek Basin, North Carolina, USA

    NASA Astrophysics Data System (ADS)

    Kraemer, S. R.

    2002-05-01

    The objective of this research is to test the utility of simple functions of spatially integrated and temporally averaged ground water residence times in shallow groundwatersheds with field observations and detailed computer simulations. The residence time of water in the subsurface is arguably a surrogate of aquifer sensitivity to contamination --- short contact time in subsurface media may result in reduced contaminant assimilation prior to discharge to a well or stream. Residence time is an established criterion for the delineation of wellhead protection areas. The residence time of water may also have application in assessing the connection between landscape and fair weather loadings of non-point source pollution to streams, such as the drainage of nitrogen-nitrate from agricultural fields as base flow. The field setting of this study includes a hierarchy of catchments in the Contentnea Creek basin (2600 km2) of North Carolina, USA, centered on the intensive coastal plain field study site at Lizzie, NC (1.2+km^2), run by the US Geological Survey and the NC Department of Environment and Natural Resources of Raleigh, NC. Analytic element models are used to define the advective flow field and regional boundary conditions. The issues of conceptual model complexity are explored using the multi-layer object oriented analytic element model Tim, and by embedding the finite difference model MODFLOW within the analytic element model GFLOW copyright. The models are compared to observations of hydraulic head, base flow separations, and aquifer geochemistry and age dating evidence. The resulting insights are captured and mapped across the basin as zones of average aquifer residence time using ArcView copyright GIS tools. Preliminary results and conclusions will be presented. Mention of commercial software does not constitute endorsement or recommendation for use.

  1. Agricultural Wastes.

    ERIC Educational Resources Information Center

    Jewell, W. J.; Switzenbaum, M. S.

    1978-01-01

    Presents a literature review of agricultural wastes, covering publications of 1976-77. Some of the areas covered are: (1) water characteristics and impacts; (2) waste treatment; (3) reuse of agricultural wastes; and (4) nonpoint pollution sources. A list of 150 references is also presented. (HM)

  2. VOCATIONAL AGRICULTURE.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Research Coordinating Unit.

    TO ASSIST THOSE WHO MAKE DECISIONS RELATING TO EDUCATIONAL PROGRAMS IN AGRICULTURE, RECENT RESEARCH IN VOCATIONAL AGRICULTURE IS SUMMARIZED. A 1963 STUDY TREATS THE RELATIONSHIP BETWEEN WORK EXPERIENCE AND STUDENT CHARACTERISTICS, PLANS, AND ASPIRATIONS. STUDIES ON POST-SECONDARY EDUCATION CONCERN GUIDELINES FOR TECHNICIAN PROGRAMS, JUSTIFICATION…

  3. Numerical Investigation of the Spatiotemporal Contribution of Tile Drainage to Stream Flow

    NASA Astrophysics Data System (ADS)

    Thomas, N. W.; Schilling, K. E.; Weber, L. J.

    2015-12-01

    Tile drainage systems are pervasive in the Central U.S., significantly altering the hydrologic system. A physically based coupled hydrologic model was applied to a 45 km2 agricultural Iowa watershed. The tile drainage contribution to stream flow (QT/Q) was derived from a tracer driven analysis of instream surface water. QT/Q varied instantaneously from 6% to 71 % at the basin outlet, with tile flow correlating linearly with total stream flow. In low precipitation periods 62 % of stream flow traveled through the tile system. In heavy precipitation periods a dilution effect shifted QT/Q to 27 %. Precipitation driven events produced a strong positive logarithmic correlation between QT/Q and drainage area. The addition of precipitation into the system saturated near surface soils, increased lateral soil water movement, and diluted the relatively stable instream tile flow. A negative logarithmic trend in QT/Q to drainage area persisted non-event durations. Larger groundwater (non-tile) contribution to stream flow at the outlet diluted instream tile flow at increased drainage areas. Logarithmic regression slopes were consistent for event and non-event periods, respectively. While, the intercept responded in a predicable manner to precipitation intensity. This study, indicates a strong systematic response of QT/Q to meteorological forcing, drainage area over a single year.

  4. Agricultural Energy Practices. Agriculture Energy.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with agricultural energy practices. Its objective is for the student to be able to discuss energy use and conservation of resources in the production of agricultural products. Some topics covered are basic uses of direct energy in…

  5. Agriculture Education. Agricultural Metal Working.

    ERIC Educational Resources Information Center

    Stuttgart Public Schools, AR.

    This curriculum guide is designed for group instruction of secondary agricultural education students enrolled in one or two semester-long courses in agricultural metal working. The guide presents units of study in the following areas: (1) oxyacetylene welding, (2) arc welding, (3) sheet metal, (4) blueprint reading for welders and (5) job…

  6. 24 CFR 3285.604 - Drainage system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... § 3285.604 Drainage system. (a) Crossovers. Multi-section homes with plumbing in more than one section require drainage system crossover connections to join all sections of the home. The crossover design requirements are located in, and must be designed in accordance with, § 3280.610 of this chapter. (b)...

  7. Modeling coastal plain drainage ditches with SWAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the low-relief Eastern Shore region of Maryland, extensive land areas used for crop production require drainage systems either as tile drains or open ditches. The prevalence of drainage ditches in the region is being linked to increased nutrient loading of the Chesapeake Bay. Process-based water ...

  8. 24 CFR 3280.610 - Drainage systems.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... siphonage, aspiration, or forcing of trap seals under conditions of ordinary use. (b) Materials—(1) Pipe... iron, or other listed or approved materials. (2) Fittings. Drainage fittings shall be recessed drainage pattern with smooth interior waterways of the same diameter as the piping and shall be of a...

  9. Acid mine drainage prediction and remediation

    SciTech Connect

    Robb, G.; Robinson, J.

    1996-12-31

    The use of constructed wetlands for treatment of acid mine drainage is discussed in the article. Drainage characteristics and mine water flow rate are identified as important predictors of remediation success. Aerobic and anaerobic chemical reaction processes are described. Problems and potential uses of wetlands are briefly described.

  10. Managing tile drainage, subirrigation, and nitrogen fertilization to enhance crop yields and reduce nitrate loss.

    PubMed

    Drury, C F; Tan, C S; Reynolds, W D; Welacky, T W; Oloya, T O; Gaynor, J D

    2009-01-01

    Improving field-crop use of fertilizer nitrogen is essential for protecting water quality and increasing crop yields. The objective of this study was to determine the effectiveness of controlled tile drainage (CD) and controlled tile drainage with subsurface irrigation (CDS) for mitigating off-field nitrate losses and enhancing crop yields. The CD and CDS systems were compared on a clay loam soil to traditional unrestricted tile drainage (UTD) under a corn (Zea Mays L.)-soybean (Glycine Max. (L.) Merr.) rotation at two nitrogen (N) fertilization rates (N1: 150 kg N ha(-1) applied to corn, no N applied to soybean; N2: 200 kg N ha(-1) applied to corn, 50 kg N ha(-1) applied to soybean). The N concentrations in tile flow events with the UTD treatment exceeded the provisional long-term aquatic life limit (LT-ALL) for freshwater (4.7 mg N L(-1)) 72% of the time at the N1 rate and 78% at the N2 rate, whereas only 24% of tile flow events at N1 and 40% at N2 exceeded the LT-ALL for the CDS treatment. Exceedances in N concentration for surface runoff and tile drainage were greater during the growing season than the non-growing season. At the N1 rate, CD and CDS reduced average annual N losses via tile drainage by 44 and 66%, respectively, relative to UTD. At the N2 rate, the average annual decreases in N loss were 31 and 68%, respectively. Crop yields from CDS were increased by an average of 2.8% relative to UTD at the N2 rate but were reduced by an average of 6.5% at the N1 rate. Hence, CD and CDS were effective for reducing average nitrate losses in tile drainage, but CDS increased average crop yields only when additional N fertilizer was applied.

  11. Influence of three aquatic macrophytes on mitigation of nitrogen species from agricultural runoff

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural runoff containing nitrogen fertilizer is a major contributor to eutrophication in aquatic systems. One method of lowering amounts of nitrogen entering rivers or lakes is the transport of runoff through vegetated drainage ditches. Drainage ditch vegetation can enhance the mitigation of...

  12. Numerical investigation of the spatial scale and time dependency of tile drainage contribution to stream flow

    NASA Astrophysics Data System (ADS)

    Thomas, Nicholas W.; Arenas, Antonio A.; Schilling, Keith E.; Weber, Larry J.

    2016-07-01

    Tile drainage systems are pervasive in the Central U.S., significantly altering the hydrologic system. The purpose of this study was to assess the effects of tile drainage systems on streamflow. A physically based coupled hydrologic model was applied to a 45 km2 agricultural Iowa watershed. Tile drainage was incorporated though an equivalent porous medium approach, calibrated though numerical experimentation. Experimental results indicated that a significant increase in hydraulic conductivity of the equivalent medium layer was needed to achieve agreement in total outflow with an explicit numerical representation of a tiled system. Watershed scale analysis derived the tile drainage contribution to stream flow (QT/Q) from a numerical tracer driven analysis of instream surface water. During precipitation events tile drainage represented 30% of stream flow, whereas during intervals between precipitations events, 61% of stream flow originated from the tile system. A division of event and non-event periods produced strong correlations between QT/Q and drainage area, positive for events, and negative for non-events. The addition of precipitation into the system acted to saturate near surface soils, increase lateral soil water movement, and dilute the relatively stable instream tile flow. Increased intensity precipitation translated the QT/Q relationship downward in a consistent manner. In non-event durations, flat upland areas contributed large contributions of tile flow, diluted by larger groundwater (non-tile) contribution to stream flow in the downstream steeper portion of the watershed. Study results provide new insights on the spatiotemporal response of tile drainage to precipitation and contributions of tile drainage to streamflow at a watershed scale, with results having important implications for nitrate transport.

  13. Introduction: energy and the subsurface.

    PubMed

    Christov, Ivan C; Viswanathan, Hari S

    2016-10-13

    This theme issue covers topics at the forefront of scientific research on energy and the subsurface, ranging from carbon dioxide (CO2) sequestration to the recovery of unconventional shale oil and gas resources through hydraulic fracturing. As such, the goal of this theme issue is to have an impact on the scientific community, broadly, by providing a self-contained collection of articles contributing to and reviewing the state-of-the-art of the field. This collection of articles could be used, for example, to set the next generation of research directions, while also being useful as a self-study guide for those interested in entering the field. Review articles are included on the topics of hydraulic fracturing as a multiscale problem, numerical modelling of hydraulic fracture propagation, the role of computational sciences in the upstream oil and gas industry and chemohydrodynamic patterns in porous media. Complementing the reviews is a set of original research papers covering growth models for branched hydraulic crack systems, fluid-driven crack propagation in elastic matrices, elastic and inelastic deformation of fluid-saturated rock, reaction front propagation in fracture matrices, the effects of rock mineralogy and pore structure on stress-dependent permeability of shales, topographic viscous fingering and plume dynamics in porous media convection.This article is part of the themed issue 'Energy and the subsurface'.

  14. Phylogenetic relationships among subsurface microorganisms

    SciTech Connect

    Nierzwicki-Bauer, S.A.

    1991-01-01

    This project involves the development of group specific 16S ribosomal RNA-targeted oligonucleotide hybridization probes for the rapid detection of specific types of subsurface organisms (e.g., groups of microbes that share certain physiological traits). Major accomplishments for the period of 6/91 to 12/1/91 are described. Nine new probes have been synthesized on the basis of published 16S rRNA sequence data from the Ribosomal Database Project. We have initiated rapid screening of many of the subsurface microbial isolates obtained from the P24 borehole at the Savannah River Site. To date, we have screened approximately 50% of the isolates from P24. We have optimized our {und in situ} hybridization technique, and have developed a cell blot hybridization technique to screen 96 samples on a single blot. This is much faster than reading 96 individual slides. Preliminary experiments have been carried out which indicate specific nutrients can be used to amplify rRNA only in those organisms capable of metabolizing those nutrients. 1 tab., 2 figs.

  15. Geohydrologic reconnaissance of drainage wells in Florida

    USGS Publications Warehouse

    Kimrey, J.O.; Fayard, L.D.

    1984-01-01

    Drainage wells are used to inject surface waters directly into an aquifer, or shallow ground waters directly into a deeper aquifer, primarily by gravity. Such wells in Florida may be grouped into two broad types: (1) surface-water injection wells, and (2) interaquifer connector wells. Drainage wells of the first type are further categorized as either Floridan aquifer drainage wells or Biscayne aquifer drainage wells. Floridan aquifer drainage wells are commonly used to supplement drainage for urban areas in karst terranes of central and north Florida. Data are available for 25 wells in the Ocala, Live Oak, and Orlando areas that allow comparison of the quality of water samples from these Floridan aquifer drainage wells with allowable contaminant levels. Comparison indicates that maximum contaminant levels for turbidity, color, and iron, manganese, and lead concentrations are equaled or exceeded in some drainage-well samples, and relatively high counts for coliform bacteria are present in most wells. Biscayne aquifer drainage wells are used locally to dispose of stormwater runoff and other surplus water in southeast Florida, where large numbers of these wells have been permitted in Dade and Broward Counties. The majority of these wells are used to dispose of water from swimming pools or to dispose of heated water from air-conditioning units. The use of Biscayne aquifer drainage wells may have minimal effect on aquifer potability so long as injection of runoff and industrial wates is restricted to zones where chloride concentrations exceed 1,500 milligrams per liter. Interaquifer connector wells are used in the phosphate mining areas of Polk and Hillsborough Counties, to drain mines and recharge the Floridan aquifer. Water-quality data available from 13 connector wells indicate that samples from most of these wells exceed standards values for iron concentration and turbidity. One well yielded a highly mineralized water, and samples from 6 of the other 12 wells exceed

  16. Agricultural Geophysics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The four geophysical methods predominantly used for agricultural purposes are resistivity, electromagnetic induction, ground penetrating radar (GPR), and time domain reflectometry (TDR). Resistivity and electromagnetic induction methods are typically employed to map lateral variations of apparent so...

  17. Agriculture Sectors

    EPA Pesticide Factsheets

    The Agriculture sectors comprise establishments primarily engaged in growing crops, raising animals, and harvesting fish and other animals. Find information on compliance, enforcement and guidance on EPA laws and regulations on the NAICS 111 & 112 sectors.

  18. Agricultural Microbiology.

    ERIC Educational Resources Information Center

    Brill, Winston J.

    1981-01-01

    Elucidates strategies for applying microbiological techniques to traditional agricultural practices. Discusses the manipulation of microorganisms that live with plants and also the problems involved in the introduction of new genes into crop plants by recombinant DNA methods. (CS)

  19. Oxygen-18 dynamics in precipitation and streamflow in a semi-arid agricultural watershed, Eastern Washington

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding flow pathways and mechanisms that generate streamflow is important to understanding agrochemical contamination in surface waters in agricultural watersheds. Two environmental tracers, oxygen-18 and electrical conductivity (EC), were monitored in tile drainage (draining 12 ha) and stre...

  20. Differences in instream wood characteristics between channelized and unchannelized agricultural headwater streams in central Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Instream wood is an important resource for stream biota because it provides cover for fishes, substrate for macroinvertebrates, and increases habitat diversity. However, current management of instream wood within channelized agricultural headwater streams (drainage ditches) involves removing instrea...

  1. Agricultural Waste.

    PubMed

    Shu, Huajie; Zhang, Panpan; Chang, Chein-Chi; Wang, Renqing; Zhang, Shuping

    2015-10-01

    The management and disposal of agricultural waste are drawn more and more attention because of the increasing yields and negative effects on the environment. However, proper treatments such as converting abundant biomass wastes into biogas through anaerobic digestion technology, can not only avoid the negative impacts, but also convert waste into available resources. This review summarizes the studies of nearly two hundred scholars from the following four aspects: the characterization, reuse, treatment, and management of agricultural waste.

  2. Field-scale modeling of subsurface tile-drained soils using an equivalent-medium approach

    NASA Astrophysics Data System (ADS)

    Carlier, Jean Philippe; Kao, Cyril; Ginzburg, Irina

    2007-07-01

    SummaryResearch conducted for the last 35 years has shown that subsurface drainage has a significant impact on hydrology and contaminant transport. This can be observed at the field-scale and also at the watershed scale. Impacts are always associated with modifying otherwise natural flow paths. Most computer model representations of drainage have been drawn at the field-scale. These models require relatively precise data that are usually unavailable when simulating hydrology and water quality in large watersheds. We believe that in this case drainage representation should be simplified and yet closely match observations. As a first step towards incorporating drainage systems into large-scale hydrological models, we propose an equivalent representation of drains buried in a soil profile by using a homogeneous anisotropic porous medium without drains. This representation is based on a "self-consistent" approach and on geometrical considerations. Simplification is such that calculating the equivalent hydraulic conductivity requires only information on the main length and spacing of the tile drains and not on their precise location. This approach also provides a much simpler discretisation of the domain because of the absence of internal boundary conditions on the drainage pipes. Compared to other methods that have simplified drainage representation in existing watershed models, it requires no parameter fitting. Two alternatives to the method are presented: in the first one, the soil profile equipped with the actual drain pipes is represented by an equivalent, horizontally layered system with no pipes; in the second, the layered system has been replaced with an equivalent homogeneous profile. The efficiency of these approaches was tested against a classical representation of tile drains using the SWMS 3D code, which solves the Richards equation for a typical drained plot configuration. The equivalent-medium approach appears to give satisfying results for global water

  3. Optimization of denitrifying bioreactor performance with agricultural residue-based filter media

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Denitrification bioreactors are a promising technology for mitigation of nitrate-nitrogen (NO3-N) losses in subsurface drainage water. Bioreactors are constructed with carbon substrates, typically wood chips, to provide a substrate for denitrifying microorganisms. Columns were packed with wood chips...

  4. Agriculture: About EPA's National Agriculture Center

    EPA Pesticide Factsheets

    EPA's National Agriculture Center (Ag Center), with the support of the United States Department of Agriculture, serves growers, livestock producers, other agribusinesses, and agricultural information/education providers.

  5. The change of nature and the nature of change in agricultural landscapes: Hydrologic regime shifts modulate ecological transitions

    NASA Astrophysics Data System (ADS)

    Foufoula-Georgiou, Efi; Takbiri, Zeinab; Czuba, Jonathan A.; Schwenk, Jon

    2015-08-01

    Hydrology in many agricultural landscapes around the world is changing in unprecedented ways due to the development of extensive surface and subsurface drainage systems that optimize productivity. This plumbing of the landscape alters water pathways, timings, and storage, creating new regimes of hydrologic response and driving a chain of environmental changes in sediment dynamics, nutrient cycling, and river ecology. In this work, we nonparametrically quantify the nature of hydrologic change in the Minnesota River Basin, an intensively managed agricultural landscape, and study how this change might modulate ecological transitions. During the growing season when climate effects are shown to be minimal, daily streamflow hydrographs exhibit sharper rising limbs and stronger dependence on the previous-day precipitation. We also find a changed storage-discharge relationship and show that the artificial landscape connectivity has most drastically affected the rainfall-runoff relationship at intermediate quantiles. Considering the whole year, we show that the combined climate and land use change effects reduce the inherent nonlinearity in the dynamics of daily streamflow, perhaps reflecting a more linearized engineered hydrologic system. Using a simplified dynamic interaction model that couples hydrology to river ecology, we demonstrate how the observed hydrologic change and/or the discharge-driven sediment generation dynamics may have modulated a regime shift in river ecology, namely extirpation of native mussel populations. We posit that such nonparametric analyses and reduced complexity modeling can provide more insight than highly parameterized models and can guide development of vulnerability assessments and integrated watershed management frameworks.

  6. Evaluation of pore-water samplers at a drainage ditch, Installation Restoration Site 4, Naval Air Station Corpus Christi, Corpus Christi, Texas, 2005–06

    USGS Publications Warehouse

    Vroblesky, Don A.; Casey, Clifton C.

    2007-01-01

    The U.S. Geological Survey, in cooperation with the Naval Facilities Engineering Command Southeast, used innovative sampling methods to investigate ground-water contamination by chlorobenzenes beneath a drainage ditch on the southwestern side of Installation Restoration Site 4, Naval Air Station Corpus Christi, Corpus Christi, Texas, during 2005-06. The drainage ditch, which is a potential receptor for ground-water contaminants from Installation Restoration Site 4, intermittently discharges water to Corpus Christi Bay. This report evaluates a new type of pore-water sampler developed for this investigation to examine the subsurface contamination beneath the drainage ditch. The new type of pore-water sampler appears to be an effective approach for long-term monitoring of ground water in the sand and organic-rich mud beneath the drainage ditch.

  7. Identifying priority zones in an agricultural catchment to mitigate glyphosate runoff

    NASA Astrophysics Data System (ADS)

    Joris, Ingeborg; Desmet, Nele; Wilczek, Daniel; Boënne, Wesley; Seuntjens, Piet; Koopmans, Kim; Bylemans, Dany; Wouters, Katrien; Vandaele, Karel

    2015-04-01

    Pesticide concentrations in rivers generally have a very dynamic signature and are strongly dependent on time and space. The dynamic time course is due to the time- and space-variant input conditions resulting from fast overland (runoff and erosion, direct losses) and subsurface flow (artificial drainage), directly connecting surfaces and/or agricultural fields where pesticides are applied, to receiving rivers. A thorough understanding of pesticide behavior at the watershed scale is needed to increase the effectiveness of mitigation measures. We developed a method to derive priority zones for applying mitigation measures for erosion control and mitigation of glyphosate runoff in an agricultural catchment. The study catchment was selected based on results from geospatial pesticide emission modeling, historical glyphosate concentrations, and crop cover. Priority zones were derived based on a risk map which includes information about the topography, crop cover, the estimated glyphosate use, the potential erosion risk, and the connectivity of the agricultural parcels to the river. The theoretical risk map was then validated in the field using field observations of runoff during stormflow events, and observations of roads short-circuiting the runoff to the river. The validated risk map was used to define priority zones for measures related to erosion control. Suggestions for specific measures such as grass buffer strips and small dams at the field scale were made. The information will be used to target farmers that may have a significant impact on the glyphosate load to surface water. Those farmers will be encouraged to participate in a voluntary erosion control program supported by the local government. The effect of mitigation measures on the glyphosate concentrations in the river will be assessed by monitoring two years before and three years after implementation of the measures. We will present the general setup of the study and the selection methodology of the

  8. [Thoracic drainage in trauma emergencies].

    PubMed

    Bergaminelli, C; De Angelis, P; Gauthier, P; Salzano, A; Vecchio, G

    1999-10-01

    A group of 191 cases of emergency tube thoracostomy for acute trauma reviewed retrospectively from March 1993 to March 1998 is reported. Of this group 169 were men and 22 were women. Their ages ranged from 16 to 73 years. The causes were as follows: 89 cases (46%) road accident; 33 cases (17%) accidental trauma; 33 cases (17%) someone else violence (assault, gunshot or stab wound); 15 cases (8%) work accident; 11 cases (6%) domestic accident and 5 cases (3%) iatrogenic trauma. In 32 patients a diagnosis of pneumothorax was made (2 tension, 11 for penetrating chest injuries, 19 after blunt trauma). In 2 cases of tension pneumothorax and in 3 cases of open pneumothorax a chest tube (24-28 Fr) in the third space in the mid-clavicular line was introduced. In the other patients it was decided to place a chest tube in the mid-axillary line in the fifth intercostal space to drain pneumothorax. Only in 7 cases suction was necessary. Fifty-four hemothorax (3 bilateral) were treated in 11 cases using thoracentesis, while the remaining cases were treated using the insertion of multiple drainage holes in the intercostal space (fifth in the mid-axillary line directed inferiorly and posteriorly). One hundred and three were the cases of hemopneumothorax: 24 of them received 2 chest tubes, the first (20-26 Fr) apically in the second intercostal space in the mid-clavicular line, the second (32-38 Fr) in the fifth intercostal space in the mid-axillary line. All the other cases were treated using a single thoracostomy. In 14 cases suction was applied. Two cases of chylothorax resolved by a large tube positioned in the chest (fifth intercostal space in the mid-axillary line) with a constant negative pressure were also observed. Duration of tube drainage ranged from 4 and 18 days, with an average of 11 days. Five infections of thoracostomy site and 1 empyema resolved by rethoracotomy were observed. Moreover, there were 3 complications: 2 subcutaneous placements and 1 little laceration

  9. Endoscopic Gallbladder Drainage for Acute Cholecystitis

    PubMed Central

    Widmer, Jessica; Alvarez, Paloma; Sharaiha, Reem Z.; Gossain, Sonia; Kedia, Prashant; Sarkaria, Savreet; Sethi, Amrita; Turner, Brian G.; Millman, Jennifer; Lieberman, Michael; Nandakumar, Govind; Umrania, Hiren; Gaidhane, Monica

    2015-01-01

    Background/Aims Surgery is the mainstay of treatment for cholecystitis. However, gallbladder stenting (GBS) has shown promise in debilitated or high-risk patients. Endoscopic transpapillary GBS and endoscopic ultrasound-guided GBS (EUS-GBS) have been proposed as safe and effective modalities for gallbladder drainage. Methods Data from patients with cholecystitis were prospectively collected from August 2004 to May 2013 from two United States academic university hospitals and analyzed retrospectively. The following treatment algorithm was adopted. Endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy and cystic duct stenting was initially attempted. If deemed feasible by the endoscopist, EUS-GBS was then pursued. Results During the study period, 139 patients underwent endoscopic gallbladder drainage. Among these, drainage was performed in 94 and 45 cases for benign and malignant indications, respectively. Successful endoscopic gallbladder drainage was defined as decompression of the gallbladder without incidence of cholecystitis, and was achieved with ERCP and cystic duct stenting in 117 of 128 cases (91%). Successful endoscopic gallbladder drainage was also achieved with EUS-guided gallbladder drainage using transmural stent placement in 11 of 11 cases (100%). Complications occurred in 11 cases (8%). Conclusions Endoscopic gallbladder drainage techniques are safe and efficacious methods for gallbladder decompression in non-surgical patients with comorbidities. PMID:26473125

  10. The Geochemistry of Acid Mine Drainage

    NASA Astrophysics Data System (ADS)

    Blowes, D. W.; Ptacek, C. J.; Jambor, J. L.; Weisener, C. G.

    2003-12-01

    Mine wastes are the largest volume of materials handled in the world (ICOLD, 1996). The generation of acidic drainage and the release of water containing high concentrations of dissolved metals from these wastes is an environmental problem of international scale. Acidic drainage is caused by the oxidation of sulfide minerals exposed to atmospheric oxygen. Although acid drainage is commonly associated with the extraction and processing of sulfide-bearing metalliferous ore deposits and sulfide-rich coal, acidic drainage can occur wherever sulfide minerals are excavated and exposed to atmospheric oxygen. Engineering projects, including road construction, airport development, and foundation excavation are examples of civil projects that have resulted in the generation of acidic drainage. On United States Forest Service Lands there are (2-5)×104 mines releasing acidic drainage (USDA, 1993). Kleinmann et al. (1991) estimated that more than 6,400 km of rivers and streams in the eastern United States have been adversely affected by mine-drainage water. About (0.8-1.6)×104 km of streams have been affected by metal mining in the western United States. The annual worldwide production of mine wastes exceeded 4.5 Gt in 1982 (ICOLD, 1996). Estimated costs for remediating mine wastes internationally total in the tens of billions of dollars ( Feasby et al.,1991).

  11. Water Flow and Lake Drainage Beneath Antarctica

    NASA Astrophysics Data System (ADS)

    Willis, I. C.; Long, S. M.; Peters, N. J.; Arnold, N. S.

    2008-12-01

    We use 5 km resolution surface and bed DEMs of Antarctica to calculate the subglacial hydraulic potential, and location of drainage catchments and major drainage pathways for the Antarctic Ice Sheet. We find close correlations between sinks in the hydraulic potential, the location of major drainage pathways and the position of known subglacial lakes. We use a thermo-mechanical ice sheet dynamics model with an assumed geothermal heat-flux to calculate energy supply and melt rates beneath the ice sheet. Accumulating this water along the drainage pathways allows us to calculate the steady state water flux to all known lakes (which range between ~ 0.1 and ~ 10m3 s-1) and in the drainage pathways as they enter the ocean (which range from ~ 1 to ~ 100m3 s-1). For different assumed lake drainage event discharges, we estimate a range of jokulhlaup frequencies for each lake. For the observed 1996-8 Adventure Subglacial Trench lake drainage event of ~ 1.8 km3, we estimate a flood frequency of 25 years. Finally, we use Nye's (1976) theory to model the time dependent discharge associated with the Adventure Trench jokulhlaup and can match theory to the observed surface altimetry data for realistic values of initial conduit diameter and roughness.

  12. Use of a flashiness index to predict phosphorus losses from subsurface drains on a Swedish farm with clay soils

    NASA Astrophysics Data System (ADS)

    Ulén, Barbro; Stenberg, Maria; Wesström, Ingrid

    2016-02-01

    Risk assessment for elevated leaching losses of phosphorus (P) from agricultural land is commonly based on indices, since such losses are highly episodic and difficult to predict. Here a flashiness index (FI) representing changes in daily water flow from drainage systems was estimated from measured discharge (agrohydrological years 2004-2013) after reconstruction of subsurface drainage systems in 16 fields on a former swine farm. The fields were analysed for ammonium lactate-extractable soil P (P-AL), clay, carbon and other soil parameters in 2004. Transport of total P (TP), dissolved reactive P (DRP) and unreactive P (UP) was estimated from concentrations in composite water samples taken flow-proportionally up to 20 times per year. On average, 2.20 kg TP ha-1 yr-1 was leached, with 27% in DRP form, from the entire farm. FI was significantly negatively correlated (Pearson correlation coefficient p < 0.05) to mean yearly discharge from each field. Stepwise regression demonstrated that FI index was the most important single explanatory parameter for flow-proportional yearly mean concentration of unreactive P losses (UP) from each field, with a coefficient of determination (r2) of 0.67. The corresponding concentration of dissolved reactive P (DRP) was significantly positively correlated (p = 0.015) to soil P-AL and FI. A regression model for TP leaching losses based on FI, P-AL and yearly discharge (Q) from 11 of the fields over nine years (r2 = 0.67, p = 0.002) was validated against TP leaching from the remaining five fields (32% of farm area). Root mean square error (RMSE) was 0.43, which represented 20% of measured leaching (mean 2.14 kg TP ha-1 yr-1). For individual years, RMSE for different fields was 37-80% of measured TP leaching (0.8-3.7 kg TP ha-1 yr-1). The FI index could be used together with soil P test to predict P leaching from individual fields of a drained farm.

  13. Drainage investment and wetland loss: an analysis of the national resources inventory data

    USGS Publications Warehouse

    Douglas, Aaron J.; Johnson, Richard L.

    1994-01-01

    The United States Soil Conservation Service (SCS) conducts a survey for the purpose of establishing an agricultural land use database. This survey is called the National Resources Inventory (NRI) database. The complex NRI land classification system, in conjunction with the quantitative information gathered by the survey, has numerous applications. The current paper uses the wetland area data gathered by the NRI in 1982 and 1987 to examine empirically the factors that generate wetland loss in the United States. The cross-section regression models listed here use the quantity of wetlands, the stock of drainage capital, the realty value of farmland and drainage costs to explain most of the cross-state variation in wetland loss rates. Wetlands preservation efforts by federal agencies assume that pecuniary economic factors play a decisive role in wetland drainage. The empirical models tested in the present paper validate this assumption.

  14. Water and Nutrient Balances in a Large Tile-Drained Agricultural Catchment: A Distributed Modeling Study

    SciTech Connect

    Li, Hongyi; Sivapalan, Murugesu; Tian, Fuqiang; Liu, Dengfeng

    2010-11-16

    This paper presents the development and implementation of a distributed model of coupled water nutrient processes, based on the representative elementary watershed (REW) approach, to the Upper Sangamon River Basin, a large, tile-drained agricultural basin located in central Illinois, mid-west of USA. Comparison of model predictions with the observed hydrological and biogeochemical data, as well as regional estimates from literature studies, shows that the model is capable of capturing the dynamics of water, sediment and nutrient cycles reasonably well. The model is then used as a tool to gain insights into the physical and chemical processes underlying the inter- and intra-annual variability of water and nutrient balances. Model predictions show that about 80% of annual runoff is contributed by tile drainage, while the remainder comes from surface runoff (mainly saturation excess flow) and subsurface runoff. It is also found that, at the annual scale nitrogen storage in the soil is depleted during wet years, and is supplemented during dry years. This carryover of nitrogen storage from dry year to wet year is mainly caused by the lateral loading of nitrate. Phosphorus storage, on the other hand, is not affected much by wet/dry conditions simply because the leaching of it is very minor compared to the other mechanisms taking phosphorous out of the basin, such as crop harvest. The analysis then turned to the movement of nitrate with runoff. Model results suggested that nitrate loading from hillslope into the channel is preferentially carried by tile drainage. Once in the stream it is then subject to in-stream denitrification, the significant spatio-temporal variability of which can be related to the variation of the hydrologic and hydraulic conditions across the river network.

  15. Microbial processes and subsurface contaminants

    NASA Astrophysics Data System (ADS)

    Molz, Fred J.

    A Chapman Conference entitled “Microbial Processes in the Transport, Fate, and In Situ Treatment of Subsurface Contaminants” was held in Snowbird, Utah, October 1-3, 1986. Members of the program committee and session chairmen were Lenore Clesceri (Rensselaer Polytechnic Institute, Troy, N.Y.), David Gibson (University of Texas, Austin), James Mercer (GeoTrans, Inc., Herndon , Va.), Donald Michelsen (Virginia Polytechnic Institute and State University, Blacksburg), Fred Molz (Auburn University, Auburn, Ala.), Bruce Rittman (University of Illinois, Urbana), Gary Sayler (University of Tennessee, Knoxville), and John T. Wilson (U.S. Environmental Protection Agency, Ada, Okla.). The following report attempts to highlight the six sessions that constituted the conference. For additional information, including a bound summary and abstracts, contact Fred J. Molz, Civil Engineering Department, Auburn University, AL 36849 (telephone: 205-826-4321).

  16. Hydrogeologic controls on nitrate transport in a small agricultural catchment, Iowa

    USGS Publications Warehouse

    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.

  17. Fractal Analysis of Drainage Basins on Mars

    NASA Technical Reports Server (NTRS)

    Stepinski, T. F.; Marinova, M. M.; McGovern, P. J.; Clifford, S. M.

    2002-01-01

    We used statistical properties of drainage networks on Mars as a measure of martian landscape morphology and an indicator of landscape evolution processes. We utilize the Mars Orbiter Laser Altimeter (MOLA) data to construct digital elevation maps (DEMs) of several, mostly ancient, martian terrains. Drainage basins and channel networks are computationally extracted from DEMs and their structures are analyzed and compared to drainage networks extracted from terrestrial and lunar DEMs. We show that martian networks are self-affine statistical fractals with planar properties similar to terrestrial networks, but vertical properties similar to lunar networks. The uniformity of martian drainage density is between those for terrestrial and lunar landscapes. Our results are consistent with the roughening of ancient martian terrains by combination of rainfall-fed erosion and impacts, although roughening by other fluvial processes cannot be excluded. The notion of sustained rainfall in recent Mars history is inconsistent with our findings.

  18. Migratory bird habitat in relation to tile drainage and poorly drained hydrologic soil groups

    USGS Publications Warehouse

    Kastner, Brandi; Christensen, Victoria G.; Williamson, Tanja N.; Sanocki, Chris A.

    2016-01-01

    The Prairie Pothole Region (PPR) is home to more than 50% of the migratory waterfowl in North America. Although the PPR provides an abundance of temporary and permanent wetlands for nesting and feeding, increases in commodity prices and agricultural drainage practices have led to a trend of wetland drainage. The Northern Shoveler is a migratory dabbling duck species that uses wetland habitats and cultivated croplands in the PPR. Richland County in North Dakota and Roberts County in South Dakota have an abundance of wetlands and croplands and were chosen as the study areas for this research to assess the wetland size and cultivated cropland in relation to hydrologic soil groups for the Northern Shoveler habitat. This study used geographic information system data to analyze Northern Shoveler habitats in association with Natural Resource Conservation Service soil data. Habitats, which are spatially associated with certain hydrologic soil groups, may be at risk of artificial drainage installations because of their proximity to cultivated croplands and soil lacking in natural drainage that may become wet or inundated. Findings indicate that most wetlands that are part of Northern Shoveler habitats were within or adjacent to cultivated croplands. The results also revealed soil hydrologic groups with high runoff potential and low water transmission rates account for most of the soil within the Northern Shoveler‘s wetland and cropland habitats. Habitats near agriculture with high runoff potential are likely to be drained and this has the potential of reducing Northern Shoveler habitat.

  19. Drainage through subglacial water sheets

    NASA Astrophysics Data System (ADS)

    Creyts, Timothy T.; Schoof, Christian G.

    2009-10-01

    Subglacial drainage plays an important role in controlling coupling between glacial ice and underlying bed. Here, we study the flow of water in thin, macroporous sheets between ice and bed. Previous work shows that small perturbations in depth of a nearly parallel-sided water film grow unstably because these areas have enhanced viscous dissipation that leads to enhanced melting of an ice roof. We argue that in the presence of bed protrusions bridging a water sheet, downward motion of the ice roof can stabilize this sheet. Stability results when the rate of roof closure increases faster with water depth than the rate of viscous dissipation. We therefore modify existing theory to include protrusions that partially support the overlying glacier. Differences in the pressure on protrusions relative to water pressure drive roof closure. The mechanisms of both regelation and creep normal to the bed close the overlying ice roof and decrease the ice-bed gap. In order to account for multiple protrusion sizes along the bed (for instance, resulting from an assortment of various-sized sediment grains), we incorporate a method of partitioning overburden pressure among different protrusion size classes and the water sheet. Partitioning is dependent on the amount of ice protrusion contact and, therefore, water depth. This method allows prediction of roof closure rates. We then investigate stable, steady sheet configurations for reasonable parameter choices and find that these steady states can occur for modest water depths at very low effective pressures, as is appropriate for ice streams. Moreover, we find that multiple steady sheet thicknesses exist, raising the possibility of switches between low and high hydraulic conductivity regimes for the subglacial water system.

  20. AGRICULTURAL EXTENSION.

    ERIC Educational Resources Information Center

    FARQUHAR, R.N.

    AUSTRALIAN AGRICULTURAL EXTENSION HAS LONG EMPHASIZED TECHNICAL ADVISORY SERVICE AT THE EXPENSE OF THE SOCIOECONOMIC ASPECTS OF FARM PRODUCTION AND FARM LIFE. ONLY IN TASMANIA HAS FARM MANAGEMENT BEEN STRESSED. DEMANDS FOR THE WHOLE-FARM APPROACH HAVE PRODUCED A TREND TOWARD GENERALISM FOR DISTRICT OFFICERS IN MOST STATES. THE FEDERAL GOVERNMENT,…

  1. Agricultural Biodiversity.

    ERIC Educational Resources Information Center

    Postance, Jim

    1998-01-01

    The extinction of farm animals and crops is rarely brought up during discussions of endangered species and biodiversity; however, the loss of diversity in crops and livestock threatens the sustainability of agriculture. Presents three activities: (1) "The Colors of Diversity"; (2) "Biodiversity among Animals"; and (3) "Heirloom Plants." Discusses…

  2. Subsurface drip irrigation with micro-encapsulated trifluralin. Trifluralin residues in soils and cultivations.

    PubMed

    Spera, G; Rosati, S; Rossi, E; Scicchitano, S

    2006-01-01

    In full field and greenhouse agriculture, the subsurface water distribution with underground driplines--subsurface drip irrigation--is advantageous to obtain a better production and a simplification of cultivation practices. This technique can have a major applicative interest on condition that the roots' intrusion inside the driplines irrigators is eliminated or reduced. To reach this goal, a study has been made on vegetable greenhouse cultivations, and on subsurface drip irrigation with underground driplines protected against roots' intrusion with a product containing micro-encapsulated polyethylene Trifuralin (trifluralin). Underground pipes with driplines (without trifluralin) have constituted the confrontation thesis. The trifluralin residues have been determined through GC-ECD, according to different cultivation phases for two entire production cycles: with 30% of leaf covering, at the moment of flowering and maturation, during production and at the harvest ending, on soil, leaves and maturation, during the production and, at the harvest ending, on fruits.

  3. The MANAGE drain load database: Review and compilation of more than fifty years of North American drainage nutrient studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As agriculture in the 21st century is faced with increasing pressure to reduce negative environmental impacts while continuing to efficiently produce food, fiber, and fuel, it becomes ever more important to reflect upon more than half a century of drainage water quality research to identify paths fo...

  4. Water quality in the Santee River basin and coastal drainages, North and South Carolina, 1995-98

    USGS Publications Warehouse

    Hughes, W. Brian; Abrahamsen, Thomas A.; Maluk, Terry L.; Reuber, Eric J.; Wilhelm, Lance J.

    2000-01-01

    Surface water sampled in the Santee River basin and coastal drainages generally meets existing Federal and State guidelines for drinking-water quality and protection of aquatic life. However, urban and agricultural land uses have affected water quality, as indicated by elevated concentrations of bacteria, pesticides, and nutrients in basins dominated by these land uses.

  5. Introduction: energy and the subsurface

    PubMed Central

    Viswanathan, Hari S.

    2016-01-01

    This theme issue covers topics at the forefront of scientific research on energy and the subsurface, ranging from carbon dioxide (CO2) sequestration to the recovery of unconventional shale oil and gas resources through hydraulic fracturing. As such, the goal of this theme issue is to have an impact on the scientific community, broadly, by providing a self-contained collection of articles contributing to and reviewing the state-of-the-art of the field. This collection of articles could be used, for example, to set the next generation of research directions, while also being useful as a self-study guide for those interested in entering the field. Review articles are included on the topics of hydraulic fracturing as a multiscale problem, numerical modelling of hydraulic fracture propagation, the role of computational sciences in the upstream oil and gas industry and chemohydrodynamic patterns in porous media. Complementing the reviews is a set of original research papers covering growth models for branched hydraulic crack systems, fluid-driven crack propagation in elastic matrices, elastic and inelastic deformation of fluid-saturated rock, reaction front propagation in fracture matrices, the effects of rock mineralogy and pore structure on stress-dependent permeability of shales, topographic viscous fingering and plume dynamics in porous media convection. This article is part of the themed issue ‘Energy and the subsurface’. PMID:27597784

  6. Fluid-powered subsurface pump

    SciTech Connect

    Gipson, T.C.

    1991-12-03

    This paper describes a fluid-powered pump for attachment to small diametered coiled tubing for pumping subsurface liquid from a well production tube. It comprises: a pump housing having an upper end and a lower end, the upper end releasably attachable to a downhole end of the coiled tubing, the inside of the upper end of the housing in fluid communication with the inside of the coiled tubing; a cross head seal member dividing the pump into an upper chamber and a lower chamber, the upper chamber in fluid communication with the inside of the coiled tubing; a pump actuator extending between the upper and lower chambers, the actuator having an upper piston head sealingly fitted to reciprocate in the upper chamber and a lower piston head sealingly fitted to reciprocate in the lower chamber, the upper piston head and the lower piston head connected to each other by a connector rod sealing slidable in the cross head seal member, the actuator having a conduit for fluid communication between the upper chamber and the lower chamber, the conduit extending from an orifice in the top surface of the upper piston head, through the connector rod to a port above the top surface of the lower piston head.

  7. Subsurface Explosions in Granular Media

    NASA Astrophysics Data System (ADS)

    Lai, Shuyue; Houim, Ryan; Oran, Elaine

    2015-11-01

    Numerical simulations of coupled gas-granular flows are used to study properties of shock formation and propagation in media, such as sand or regolith on the moon, asteroids, or comets. The simulations were performed with a multidimensional fully compressible model, GRAF, which solves two sets of coupled Navier-Stokes equations, one for the gas and one for the granular medium. The specific case discussed here is for a subsurface explosion in a granular medium initiated by an equivalent of 200g of TNT in depths ranging from 0.1m to 3m. The background conditions of 100K, 10 Pa and loose initial particle volume fraction of 25% are consistent with an event on a comet. The initial blast creates a cavity as a granular shock expands outwards. Since the gas-phase shock propagates faster than the granular shock in loose, granular material, some gas and particles are ejected before the granular shock arrives. When the granular shock reaches the surface, a cap-like structure forms. This cap breaks and may fall back on the surface and in this process, relatively dense particle clusters form. At lower temperatures, the explosion timescales are increased and entrained particles are more densely packed.

  8. Changes in water budgets and sediment yields from a hypothetical agricultural field as a function of landscape and management characteristics--A unit field modeling approach

    USGS Publications Warehouse

    Roth, Jason L.; Capel, Paul D.

    2012-01-01

    humid environments. However, runoff did not increase with slope in the arid environment as was observed in the humid environment. In both environments, clayey soils exhibited the greatest amount of runoff and sediment yields while sandy soils had greater recharge and lessor runoff and sediment yield. Scenarios simulating the effects of the timing and type of tillage practice showed that no-till, conservation, and contouring tillages reduced sediment yields and, with the exception of no-till, runoff in both environments. Changes in land cover and crop type simulated the changes between the evapotransporative potential and surface roughness imparted by specific vegetations. Substantial differences in water budgets and sediment yields were observed between most agricultural crops and the natural covers selected for each environment: scrub and prairie grass for the arid environment and forest and prairie grass for the humid environment. Finally, a group of simulations was performed to model selected agricultural management practices. Among the selected practices subsurface drainage and strip cropping exhibited the largest shifts in water budgets and sediment yields. The practice of crop rotation (corn/soybean) and cover cropping (corn/rye) were predicted to increase sediment yields from a field planted as conventional corn.

  9. New method to assess manual lymph drainage using lymphoscintigraphy.

    PubMed

    de Godoy, José Maria Pereira; Iozzi, Adriana Joaquim; Azevedo, Walter Ferreira; Godoy, Maria de Fátima Guerreiro

    2012-08-27

    The aim of this study was to describe a new variation of the technique to evaluate lymph drainage utilizing lymphoscintigraphy. A LS scan marks the route of lymphatic vessels and may be used to assess both manual lymph drainage and lymph drainage after using some apparatuses. This evaluation may be dynamic, collecting images whilst performing lymph drainage or static, with scans before and after the lymph drainage procedure.

  10. Percutaneous catheter drainage of pancreatic pseudocysts.

    PubMed

    Adams, D B; Harvey, T S; Anderson, M C

    1991-01-01

    Pancreatic pseudocysts represent a complication of severe pancreatic inflammatory disease. Although operative drainage is the cornerstone of therapy for pseudocysts, we have undertaken percutaneous catheter drainage in a selected group of 28 patients over a six-year period (1982-88). This represents 42 per cent of pseudocyst patients managed by the senior author and 1.7 per cent of admissions for pancreatitis at the Medical University Hospitals during that period of time. There were 26 men and two women with an age range of 26-66 years (mean = 42.1). Twenty-six patients had alcohol abuse as the cause of pancreatitis; two were due to surgical trauma. Nondilated pancreatic ducts were demonstrated in 25 patients. Six had pancreatic ascites associated with pseudocysts. Four had previous operative drainage (2 internal and 2 external drainage procedures). Five patients received octreotide acetate, a synthetic peptide which mimics the action of somatostatin, in an attempt to aid closure of external fistulas. The mean length of catheter drainage was 48 days (range 7-210 days). Eight (29%) patients developed procedure-related complications (1 pneumothorax, 1 sheared guidewire, six drain tract infections). There was no mortality. Successful resolution of pseudocysts was achieved in 26 patients (93%). Two patients subsequently had elective caudal pancreaticojejunostomy (CPJ), and one lateral pancreaticojejunostomy (LPJ) to drain obstructed pancreatic ducts. One patient has required repeat external drainage. Percutaneous external drainage is successful in pseudocyst eradication. When underlying pancreatic pathology remains uncorrected, elective surgical decompression of obstructed, dilated ducts may be necessary.

  11. Sr isotope study in the drainage water in semi-arid irrigation district, Adana, Turley

    NASA Astrophysics Data System (ADS)

    Kume, T.; Akca, E.; Nakano, T.; Nagano, T.; Kapur, S.; Watanabe, T.

    2009-12-01

    The management of drainage water from irrigated lands is an important issue not only for agricultural planning but also for environmental conservation. In arid and semi-arid regions, drainage water is reused as irrigation water due to lack of enough fresh irrigation water and irrigation schemes. The drainage water reuse should be undertaken only if long-term deleterious effects on soil properties can be avoided. In addition to salt concentration, the origin of salts of drainage water should be examined to avoid agricultural and environmental pollution. The Lower Seyhan Irrigation Project (LSIP), Adana, Turkey, faces to the Mediterranean. In the LSIP, intensive irrigated agriculture has conducted since 1960s. Recently, total amount of applied irrigation water has been increased along with expansion of agricultural area and fertilizer input is also increasing. Some part of the southern lowest fields is under sea level. Soil salinization and shallow groundwater have been observed in the lowest part due to irrigation water seepage from upper stream and insufficient drainage. Moreover, agricultural drainage water has been used for irrigation water there, so that the salt is a mixture of several components. Therefore, geo-chemical measurements are indispensable to clarify the source of salt. In this study, we focused on the isotopic and chemical compositions of agricultural drain water of three main drainage canals in the LSIP. Seasonal changes in drainage features were examined using 87Sr/86Sr ratio (Sr isotope ratio) and major cation data. The abundances of possible end components were determined using mixing model. The result of measurements showed that there was a good relationship between 87Sr/86Sr values and reciprocal values of Sr concentration, while drain water quality clearly differed between summer and winter. This means Sr of drain water consists of several origins. The relationship and other data showed that Sr of drain water was a mixture of three

  12. Monitoring-based analysis of agriculture in Iraq

    NASA Astrophysics Data System (ADS)

    Tokareva, O.; Pasko, O.; Alshaibi, A.; Mochalov, M.

    2016-09-01

    The paper deals with change in area and structure of Iraq agricultural lands. It revealed the main reasons for the change: crisis (war, sanctions, etc.); economic (swamp and lake drainage, melioration, etc.); weather condition. Land-use intensification as a reason for reduction of agricultural land areas was not proved. The area of cultivated lands proved to correlate significantly with the level of precipitation, wheat productivity -with the average temperature in Iraq.

  13. Evaluation of the negative impacts of exposure to agricultural ditch water in fishes using streamside bioassays and field biomarkers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land use in regions of the Midwest is dominated by crop agriculture that depends on ditch drainage systems for maximum productivity. Many drainage networks comprise headwater streams that have been degraded by alteration of habitat and by introduction of agrichemicals. Understanding the relative i...

  14. Subsurface application enhances benefits of manure redistribution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustainable nutrient management requires redistribution of livestock manure from nutrient-excess areas to nutrient-deficit areas. Field experiments were conducted to assess agronomic and environmental effects of different poultry litter application methods (surface vs. subsurface) and timings (fall ...

  15. Subsurface Imaging with the Scanning Microwave Microscope

    NASA Astrophysics Data System (ADS)

    Kopanski, Joseph; You, Lin; Michelson, Jonathan; Hitz, Emily; Obeng, Yaw; Back End of the Line Reliability; Metrology Project Team

    2015-03-01

    The scanning microwave microscope (SMM) forms images from the reflected amplitude and phase of an incident RF (~ 2.3 GHz) signal. The reflected signal is a function of the properties of the tip-sample contact, but can also be influenced by buried interfaces and subsurface variations of the sample permittivity. This mechanism allows limited imaging of conductors buried within dielectrics, voids within metal, or multiple metal layers with different permittivity. Subsurface SMM data acquisition modes include passive and various active data acquisition modes. The theory of sub-surface imaging with SMM and COMSOL multi-physics simulations of specific situations will be presented. Measurements of specifically designed test structures and correlation with simulations show the sensitivity and resolution of the technique applied to imaging subsurface metal lines embedded in dielectric. Applications include metrology for back end of the line (BEOL) multi-level metallization and three-dimensional integrated circuits (3D-ICs).

  16. SUBSURFACE REPOSITORY INTEGRATED CONTROL SYSTEM DESIGN

    SciTech Connect

    D.C. Randle

    2000-01-07

    The primary purpose of this document is to develop a preliminary high-level functional and physical control system architecture for the potential repository at Yucca Mountain. This document outlines an overall control system concept that encompasses and integrates the many diverse process and communication systems being developed for the subsurface repository design. This document presents integrated design concepts for monitoring and controlling the diverse set of subsurface operations. The Subsurface Repository Integrated Control System design will be composed of a series of diverse process systems and communication networks. The subsurface repository design contains many systems related to instrumentation and control (I&C) for both repository development and waste emplacement operations. These systems include waste emplacement, waste retrieval, ventilation, radiological and air monitoring, rail transportation, construction development, utility systems (electrical, lighting, water, compressed air, etc.), fire protection, backfill emplacement, and performance confirmation. Each of these systems involves some level of I&C and will typically be integrated over a data communications network throughout the subsurface facility. The subsurface I&C systems will also interface with multiple surface-based systems such as site operations, rail transportation, security and safeguards, and electrical/piped utilities. In addition to the I&C systems, the subsurface repository design also contains systems related to voice and video communications. The components for each of these systems will be distributed and linked over voice and video communication networks throughout the subsurface facility. The scope and primary objectives of this design analysis are to: (1) Identify preliminary system-level functions and interfaces (Section 6.2). (2) Examine the overall system complexity and determine how and on what levels the engineered process systems will be monitored, controlled, and

  17. Bacterial contamination of tile drainage water and shallow groundwater under different application methods of liquid swine manure.

    PubMed

    Samarajeewa, A D; Glasauer, S M; Lauzon, J D; O'Halloran, I P; Parkin, Gary W; Dunfield, K E

    2012-05-01

    A 2 year field experiment evaluated liquid manure application methods on the movement of manure-borne pathogens (Salmonella sp.) and indicator bacteria (Escherichia coli and Clostridium perfringens) to subsurface water. A combination of application methods including surface application, pre-application tillage, and post-application incorporation were applied in a randomized complete block design on an instrumented field site in spring 2007 and 2008. Tile and shallow groundwater were sampled immediately after manure application and after rainfall events. Bacterial enumeration from water samples showed that the surface-applied manure resulted in the highest concentration of E. coli in tile drainage water. Pre-tillage significantly (p < 0.05) reduced the movement of manure-based E. coli and C. perfringens to tile water and to shallow groundwater within 3 days after manure application (DAM) in 2008 and within 10 DAM in 2007. Pre-tillage also decreased the occurrence of Salmonella sp. in tile water samples. Indicator bacteria and pathogens reached nondetectable levels within 50 DAM. The results suggest that tillage before application of liquid swine manure can minimize the movement of bacteria to tile and groundwater, but is effective only for the drainage events immediately after manure application or initial rainfall-associated drainage flows. Furthermore, the study highlights the strong association between bacterial concentrations in subsurface waters and rainfall timing and volume after manure application.

  18. Microbial life in the deep terrestrial subsurface

    SciTech Connect

    Fliermans, C.B.; Balkwill, D.L.; Beeman, R.E.

    1988-12-31

    The distribution and function of microorganisms is a vital issue in microbial ecology. The US Department of Energy`s Program, ``Microbiology of the Deep Subsurface,`` concentrates on establishing fundamental scientific information about organisms at depth, and the use of these organisms for remediation of contaminants in deep vadose zone and groundwater environments. This investigation effectively extends the Biosphere hundreds of meters into the Geosphere and has implications to a variety of subsurface activities.

  19. Floating insulated conductors for heating subsurface formations

    DOEpatents

    Burns, David; Goodwin, Charles R.

    2014-07-29

    A heating system for a subsurface formation includes a conduit located in a first opening in the subsurface formation. Three electrical conductors are located in the conduit. A return conductor is located inside the conduit. The return conductor is electrically coupled to the ends of the electrical conductors distal from the surface of the formation. Insulation is located inside the conduit. The insulation electrically insulates the three electrical conductors, the return conductor, and the conduit from each other.

  20. Use of industrial byproducts to filter phosphorus and pesticides in golf green drainage water.

    PubMed

    Agrawal, Sheela G; King, Kevin W; Moore, James F; Levison, Phil; McDonald, Jon

    2011-01-01

    Golf courses are vulnerable to phosphate (PO) and pesticide loss by infiltration of the sandy, porous grass rooting media used and through subsurface tile drainage. In this study, an effort was made to remove PO, chlorothalonil, mefenoxam, and propiconazole in a golf green's drainage water with a filter blend comprised of industrial byproducts, including granulated blast furnace slag, cement kiln dust, silica sand, coconut shell-activated carbon, and zeolite. To test this filter media, two 6-h storm events were simulated by repeat irrigation of the golf green after PO and pesticide application. Drainage flows ranged from 0.0034 to 0.6433 L s throughout the course of the simulations. A significant decrease in the chlorothalonil load for the experimental run (with filter media) was observed compared with the control (without filter media) ( < 0.05). In general, percent reductions in chlorothalonil were very high (>80%) near peak flows. In contrast, filter media was not effective in removing PO, mefenoxam, or propiconazole ( > 0.05). Instead, it appears that the filter blend added PO to the effluent above flow rates of 0.037 L s. Overall, flow rate, the amount of filter media used, and contaminant properties may have influenced the filter media's ability to remove contaminants. More research is needed to determine the optimal blend and configuration for the filter media to remove significant amounts of all contaminants investigated.

  1. Foam drainage placed on a porous substrate.

    PubMed

    Arjmandi-Tash, O; Kovalchuk, N; Trybala, A; Starov, V

    2015-05-14

    A model for drainage/imbibition of a foam placed on the top of a porous substrate is presented. The equation of liquid imbibition into the porous substrate is coupled with a foam drainage equation at the foam/porous substrate interface. The deduced dimensionless equations are solved using a finite element method. It was found that the kinetics of foam drainage/imbibition depends on three dimensionless numbers and the initial liquid volume fraction. The result shows that there are three different regimes of the process. Each regime starts after initial rapid decrease of a liquid volume fraction at the foam/porous substrate interface: (i) rapid imbibition: the liquid volume fraction inside the foam at the foam/porous substrate interface remains constant close to a final liquid volume fraction; (ii) intermediate imbibition: the liquid volume fraction at the interface with the porous substrate experiences a peak point and imbibition into the porous substrate is slower as compared with the drainage; (iii) slow imbibition: the liquid volume fraction at the foam/porous substrate interface increases to a maximum limiting value and a free liquid layer is formed between the foam and the porous substrate. However, the free liquid layer disappears after some time. The transition points between these three different drainage/imbibition regimes were delineated by introducing two dimensionless numbers.

  2. Urban Drainage Modeling and Flood Risk Management

    NASA Astrophysics Data System (ADS)

    Schmitt, Theo G.; Thomas, Martin

    The European research project in the EUREKA framework, RisUrSim (Σ!2255) has been worked out by a project consortium including industrial mathematics and water engineering research institutes, municipal drainage works as well as an insurance company. The overall objective has been the development of a simulation to allow flood risk analysis and cost-effective management for urban drainage systems. In view of the regulatory background of European Standard EN 752, the phenomenon of urban flooding caused by surcharged sewer systems in urban drainage systems is analyzed, leading to the necessity of dual drainage modeling. A detailed dual drainage simulation model is described based upon hydraulic flow routing procedures for surface flow and pipe flow. Special consideration is given to the interaction between surface and sewer flow in order to most accurately compute water levels above ground as a basis for further assessment of possible damage costs. The model application is presented for small case study in terms of data needs, model verification, and first simulation results.

  3. EFFECTIVENESS OF RESTORED WETLANDS FOR THE TREATMENT OF AGRICULTURAL RUNOFF

    EPA Science Inventory

    The integration of the tax ditches into a drainage management system provides obvious benefits, but can also present a source of significant nonpoint source pollution from agricultural runoff. Many of Delaware's tax ditches have been listed on Delaware's Clean
    Water Act 303(d)...

  4. Agricultural Education Science Activity--Nos. PS 1-6.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Agricultural Curriculum Materials Service.

    This packet contains six science learning activities that can be used in agricultural education courses. The activities cover these topics: (1) determining the effects of soil drainage on plant growth and development; (2) determining the effect of soil compaction on plant growth and development; (3) inoculating legume seeds to promote nodule…

  5. Simulating Sustainable P Management Practices in Tile-Drained Landscapes of Central Ohio Using the Agricultural Policy Environmental Extender (APEX)

    NASA Astrophysics Data System (ADS)

    Ford, W. I., III; King, K.; Williams, M.

    2014-12-01

    Despite extensive application of conservation practices to minimize sediment P delivery to streams, hypoxic conditions and harmful algal blooms persist in receiving water bodies. Tile-drainage networks are a focal point for reducing soluble P in the food-producing Midwestern United States in that they promote higher connectivity between upland soils and stream channels which decreases soil contact time, and biogeochemical alterations. A critical next step to reduce the environmental impact and maintain sustainable agriculture is to implement best management practices (BMPs) under a holistic framework that considers adverse effects to water resources and crop production, while maintaining economic feasibility. The objective of this study was to apply a robust numerical model, the Agricultural Policy Environmental Extender (APEX), in a tile-drained landscape in Central Ohio in order to evaluate the effectiveness of a suite of BMPs on soluble and particulate P delivery to stream channels. The model was applied and evaluated at two adjacent edge-of-field sites with similar soil, topographic and management characteristics (except for tillage and tile installation on the south field in 2012, preceded by more than 20 years of no-till operations). Three years of daily discharge, total suspended solids, soluble P, soluble N (NO3 and NH4), total P, total N, and crop yields were utilized to verify the model performance. Prevalent BMPs simulated within the modeling framework included drainage water management, tillage and crop rotations, the 4Rs framework (right fertilizer source, rate, time, and placement), and bioreactors. Results of the study quantify the ability of the numerical model to simulate hydrology and P transport for surface runoff and subsurface tile drainage and highlight modifications that improve model performance. Further, results highlight BMPs that effectively reduce P loads to streams while maintaining crop yields, which can later be used to inform BMPs

  6. Sub-Surface Windscreen for the Measurement of Outdoor Infrasound

    NASA Technical Reports Server (NTRS)

    Shams, Qamar A.; Burkett, Cecil G., Jr.; Comeaux, Toby; Zuckerwar, Allan J.; Weistroffer, George R.

    2008-01-01

    A windscreen has been developed that features two advantages favorable for the measurement of outdoor infrasound. First, the sub-surface location, with the top of the windscreen flush with the ground surface, minimizes the mean velocity of the impinging wind. Secondly, the windscreen material (closed cell polyurethane foam) has a sufficiently low acoustic impedance (222 times that of air) and wall thickness (0.0127 m) to provide a transmission coefficient of nearly unity over the infrasonic frequency range (0-20 Hz). The windscreen, a tightly-sealed box having internal dimensions of 0.3048 x 0.3048 x 0.3556 m, contains a microphone, preamplifier, and a cable feed thru to an external power supply. Provisions are made for rain drainage and seismic isolation. A three-element array, configured as an equilateral triangle with 30.48 m spacing and operating continuously in the field, periodically receives highly coherent signals attributed to emissions from atmospheric turbulence. The time delays between infrasonic signals received at the microphones permit determination of the bearing and elevation of the sources, which correlate well with locations of pilot reports (PIREPS) within a 320 km radius about the array. The test results are interpreted to yield spectral information on infrasonic emissions from clear air turbulence.

  7. Subsurface band application of poultry litter and its influence on Phosphorus concentration and retention after runoff from permanent pastures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Excessive P loss from agricultural fields has been identified as a major cause of eutrophication to river, lakes, and streams. To minimize and mitigate P loss from poultry litter (PL) applications, new technology is being developed for subsurface band application of litter below the soil surface. Th...

  8. Subsurface application of poultry litter and its influence on nutrient losses in runoff water from permanent pastures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Environmental pressure to reduce nutrient losses from agricultural fields has increased in recent years. To abate this nutrient loss to the environment, better management practices and new technologies need to be developed. Thus, research was conducted to evaluate if subsurface banding poultry lit...

  9. Application of manure to no-till soils: Phosphorus losses by sub-surface and surface pathways

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Concern over the acceleration of eutrophication by agricultural runoff has focused attention on manure management in no-till. We evaluated losses of phosphorus (P) in sub-surface and surface flow as a function of dairy manure application to no-till soils on a dairy farm in north-central Pennsylvania...

  10. Assessing conceptual models for subsurface reactive transport of inorganic contaminants

    USGS Publications Warehouse

    Davis, James A.; Yabusaki, Steven B.; Steefel, Carl; Zachara, John M.; Curtis, Gary P.; Redden, George D.; Criscenti, Louise J.; Honeyman, Bruce D.

    2004-01-01

    In many subsurface situations where human health and environmental quality are at risk (e.g., contaminant hydrogeology petroleum extraction, carbon sequestration, etc.),scientists and engineers are being asked by federal agency decision-makers to predict the fate of chemical species under conditions where both reactions and transport are processes of first-order importance.In 2002, a working group (WG) was formed by representatives of the U.S. Geological Survey, Environmental Protection Agency, Department of Energy Nuclear Regulatory Commission, Department of Agriculture, and Army Engineer Research and Development Center to assess the role of reactive transport modeling (RTM) in addressing these situations. Specifically the goals of the WG are to (1) evaluate the state of the art in conceptual model development and parameterization for RTM, as applied to soil,vadose zone, and groundwater systems, and (2) prioritize research directions that would enhance the practical utility of RTM.

  11. Carbon balance of sugarcane agriculture on histosols of the everglades agricultural area: review, analysis, and global energy perspectives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofuels production from crop products and cellulosic by-products, including sugarcane, has received much attention. In Florida, most sugarcane is produced on drained Histosols (organic soils) of the Everglades Agricultural Area (EAA). Subsidence has occurred via microbial oxidation since drainage i...

  12. High frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

    NASA Astrophysics Data System (ADS)

    Rozemeijer, J. C.; Visser, A.; Borren, W.; Winegram, M.; van der Velde, Y.; Klein, J.; Broers, H. P.

    2015-06-01

    High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. We designed a small scale (1 ha) field experiment to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates and the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007-2008) and after (2009-2011). For the N and P concentration measurements, we combined auto-analysers for continuous records with passive samplers for time-average concentrations at individual drain outlets. Our experimental setup yielded continuous time series for all relevant hydrological and chemical parameters, which enabled us to quantify changes in the field water and solute balance after introducing controlled drainage. We concluded that controlled drainage reduced the drain discharge and increased the groundwater storage in the field. The introduction of controlled drainage did not have clear positive effects on nutrient losses to surface water.

  13. Field Evaluation of Preferential Flow in Agricultural Soil of the Mississippi Delta

    NASA Astrophysics Data System (ADS)

    Perkins, K. S.; Nimmo, J. R.; Rose, C. E.; Coupe, R.

    2009-12-01

    In the Bogue Phalia basin in the Delta region of northwestern Mississippi, as in many farmed areas, intensive use of agricultural chemicals raises water quality concerns. The soils are fine textured and often exhibit surface ponding and runoff after irrigation and rainfall. There is extensive surface cracking during extended dry periods. Fields are typically land-formed to promote surface flow into irrigation ditches and streams that feed into larger river ecosystems. Deep percolation below the root zone has been considered to be minimal in this area; however, unsaturated zone processes, including the effects of a declining water table, are not well understood, and there are few measured unsaturated zone data relevant to deep percolation. In this study we assessed solute transport mechanisms within and below the root zone of a fallow soybean field by performing a 2-m ring infiltration experiment. Ponding continued for 67 hours using bromide and rhodamine tracers and subsurface instruments for measuring soil-water content, matric pressure, and solution sampling. Water percolated rapidly below the pond reaching 1 m depth in as little as 30 minutes, indicating preferential flow through the root zone, possibly related to shrink/swell features. Extensive lateral flow of water at shallow depths was apparent as the surface wetted outward to several meters from the pond in all directions with some evidence of preferentiality along slope toward the drainage ditch. Deeper lateral flow was detected at solution samplers 3 m from the pond edge at 5 m depth within a few weeks. Tracer was not detected in the unsaturated zone below 5 m however; the tracer was detected at the water table 12 m below land surface within 10 weeks of the experiment with concentrations increasing over a period of 10 months. A tracer mass balance also suggests the possibility for deep preferential transport of agricultural chemicals within the Bogue Phalia basin.

  14. Pesticide concentrations in frog tissue and wetland habitats in alandscape dominated by agriculture

    USGS Publications Warehouse

    Smalling, Kelly L.; Reeves, Rebecca; Muths, Erin L.; Vandever, Mark W.; Battaglin, William A.; Hladik, Michelle; Pierce, Clay L.

    2015-01-01

    Habitat loss and exposure to pesticides are likely primary factors contributing to amphibian decline in agricultural landscapes. Conservation efforts have attempted to restore wetlands lost through landscape modifications to reduce contaminant loads in surface waters and providing quality habitat to wildlife. The benefits of this increased wetland area, perhaps especially for amphibians, may be negated if habitat quality is insufficient to support persistent populations. We examined the presence of pesticides and nutrients in water and sediment as indicators of habitat quality and assessed the bioaccumulation of pesticides in the tissue of two native amphibian species Pseudacris maculata (chorus frogs) and Lithobates pipiens (leopard frogs) at six wetlands (3 restored and 3 reference) in Iowa, USA. Restored wetlands are positioned on the landscape to receive subsurface tile drainage water while reference wetlands receive water from overland run-off and shallow groundwater sources. Concentrations of the pesticides frequently detected in water and sediment samples were not different between wetland types. The median concentration of atrazine in surface water was 0.2 μg/L. Reproductive abnormalities in leopard frogs have been observed in other studies at these concentrations. Nutrient concentrations were higher in the restored wetlands but lower than concentrations thought lethal to frogs. Complex mixtures of pesticides including up to 8 fungicides, some previously unreported in tissue, were detected with concentrations ranging from 0.08 to 1500 μg/kg wet weight. No significant differences in pesticide concentrations were observed between species, although concentrations tended to be higher in leopard frogs compared to chorus frogs, possibly because of differences in life histories. Our results provide information on habitat quality in restored wetlands that will assist state and federal agencies, landowners, and resource managers in identifying and

  15. Estimating Annual Soil Carbon Loss in Agricultural Peatland Soils Using a Nitrogen Budget Approach

    PubMed Central

    Kirk, Emilie R.; van Kessel, Chris; Horwath, William R.; Linquist, Bruce A.

    2015-01-01

    Around the world, peatland degradation and soil subsidence is occurring where these soils have been converted to agriculture. Since initial drainage in the mid-1800s, continuous farming of such soils in the California Sacramento-San Joaquin Delta (the Delta) has led to subsidence of up to 8 meters in places, primarily due to soil organic matter (SOM) oxidation and physical compaction. Rice (Oryza sativa) production has been proposed as an alternative cropping system to limit SOM oxidation. Preliminary research on these soils revealed high N uptake by rice in N fertilizer omission plots, which we hypothesized was the result of SOM oxidation releasing N. Testing this hypothesis, we developed a novel N budgeting approach to assess annual soil C and N loss based on plant N uptake and fallow season N mineralization. Through field experiments examining N dynamics during growing season and winter fallow periods, a complete annual N budget was developed. Soil C loss was calculated from SOM-N mineralization using the soil C:N ratio. Surface water and crop residue were negligible in the total N uptake budget (3 – 4 % combined). Shallow groundwater contributed 24 – 33 %, likely representing subsurface SOM-N mineralization. Assuming 6 and 25 kg N ha-1 from atmospheric deposition and biological N2 fixation, respectively, our results suggest 77 – 81 % of plant N uptake (129 – 149 kg N ha-1) was supplied by SOM mineralization. Considering a range of N uptake efficiency from 50 – 70 %, estimated net C loss ranged from 1149 – 2473 kg C ha-1. These findings suggest that rice systems, as currently managed, reduce the rate of C loss from organic delta soils relative to other agricultural practices. PMID:25822494

  16. Estimating annual soil carbon loss in agricultural peatland soils using a nitrogen budget approach.

    PubMed

    Kirk, Emilie R; van Kessel, Chris; Horwath, William R; Linquist, Bruce A

    2015-01-01

    Around the world, peatland degradation and soil subsidence is occurring where these soils have been converted to agriculture. Since initial drainage in the mid-1800s, continuous farming of such soils in the California Sacramento-San Joaquin Delta (the Delta) has led to subsidence of up to 8 meters in places, primarily due to soil organic matter (SOM) oxidation and physical compaction. Rice (Oryza sativa) production has been proposed as an alternative cropping system to limit SOM oxidation. Preliminary research on these soils revealed high N uptake by rice in N fertilizer omission plots, which we hypothesized was the result of SOM oxidation releasing N. Testing this hypothesis, we developed a novel N budgeting approach to assess annual soil C and N loss based on plant N uptake and fallow season N mineralization. Through field experiments examining N dynamics during growing season and winter fallow periods, a complete annual N budget was developed. Soil C loss was calculated from SOM-N mineralization using the soil C:N ratio. Surface water and crop residue were negligible in the total N uptake budget (3 - 4 % combined). Shallow groundwater contributed 24 - 33 %, likely representing subsurface SOM-N mineralization. Assuming 6 and 25 kg N ha-1 from atmospheric deposition and biological N2 fixation, respectively, our results suggest 77 - 81 % of plant N uptake (129 - 149 kg N ha-1) was supplied by SOM mineralization. Considering a range of N uptake efficiency from 50 - 70 %, estimated net C loss ranged from 1149 - 2473 kg C ha-1. These findings suggest that rice systems, as currently managed, reduce the rate of C loss from organic delta soils relative to other agricultural practices.

  17. Pesticide concentrations in frog tissue and wetland habitats in a landscape dominated by agriculture.

    PubMed

    Smalling, Kelly L; Reeves, Rebecca; Muths, Erin; Vandever, Mark; Battaglin, William A; Hladik, Michelle L; Pierce, Clay L

    2015-01-01

    Habitat loss and exposure to pesticides are likely primary factors contributing to amphibian decline in agricultural landscapes. Conservation efforts have attempted to restore wetlands lost through landscape modifications to reduce contaminant loads in surface waters and providing quality habitat to wildlife. The benefits of this increased wetland area, perhaps especially for amphibians, may be negated if habitat quality is insufficient to support persistent populations. We examined the presence of pesticides and nutrients in water and sediment as indicators of habitat quality and assessed the bioaccumulation of pesticides in the tissue of two native amphibian species Pseudacris maculata (chorus frogs) and Lithobates pipiens (leopard frogs) at six wetlands (3 restored and 3 reference) in Iowa, USA. Restored wetlands are positioned on the landscape to receive subsurface tile drainage water while reference wetlands receive water from overland run-off and shallow groundwater sources. Concentrations of the pesticides frequently detected in water and sediment samples were not different between wetland types. The median concentration of atrazine in surface water was 0.2 μg/L. Reproductive abnormalities in leopard frogs have been observed in other studies at these concentrations. Nutrient concentrations were higher in the restored wetlands but lower than concentrations thought lethal to frogs. Complex mixtures of pesticides including up to 8 fungicides, some previously unreported in tissue, were detected with concentrations ranging from 0.08 to 1,500 μg/kg wet weight. No significant differences in pesticide concentrations were observed between species, although concentrations tended to be higher in leopard frogs compared to chorus frogs, possibly because of differences in life histories. Our results provide information on habitat quality in restored wetlands that will assist state and federal agencies, landowners, and resource managers in identifying and implementing

  18. Mine Drainage and Oil Sand Water.

    PubMed

    Wei, Xinchao; Wolfe, F Andrew; Li, Yanjun

    2015-10-01

    Mine drainage from the mining of mineral resources (coal, metals, oil sand, or industrial minerals) remains as a persistent environmental problem. This review summarizes the scientific literature published in 2014 on the technical issues related to mine drainage or mine water in active and abandoned coal/hard rock mining sites or waste spoil piles. Also included in this review is the water from oil sand operations. This review is divided into the four sections: 1) mine drainage characterization, 2) prediction and environmental impact, 3) treatment technologies, 4) oil sand water. Many papers presented in this review address more than one aspect and different sections should not be regarded as being mutuallyexclusive or all-inclusive.

  19. Nitrate exported in drainage waters of two sprinkler-irrigated watersheds.

    PubMed

    Cavero, J; Beltrán, A; Aragüés, R

    2003-01-01

    Nitrate contamination of surface waters has been linked to irrigated agriculture across the world. We determined the NO3-N loads in the drainage waters of two sprinkler-irrigated watersheds located in the Ebro River basin (Spain) and their relationship to irrigation and N management. Crop water requirements, irrigation, N fertilization, and the volume and NO3-N concentration of drainage waters were measured or estimated during two-year (Watershed A; 494 irrigated ha) and one-year (Watershed B; 470 irrigated ha) study periods. Maize (Zea mays L.) and alfalfa (Medicago sativa L.) were grown in 40 to 60% and 15 to 33% of the irrigated areas, respectively. The seasonal irrigation performance index (IPI) ranged from 92 to 100%, indicating high-quality management of irrigation. However, the IPI varied among fields and overirrigation occurred in 17 to 44% of the area. Soil and maize stalk nitrate contents measured at harvest indicated that N fertilizer rates could be decreased. Drainage flows were 68 mm yr(-1) in Watershed A and 194 mm yr(-1) in Watershed B. Drainage NO3-N concentrations were independent of drainage flows and similar in the irrigated and nonirrigated periods (average: 23-29 mg L(-1)). Drainage flows determined the exported mass of NO3-N, which varied from 18 (Watershed A) to 49 (Watershed B) kg ha(-1) yr(-1), representing 8 (Watershed A) and 22% (Watershed B) of the applied fertilizer plus manure N. High-quality irrigation management coupled to the split application of N through the sprinkler systems allowed a reasonable compromise between profitability and reduced N pollution in irrigation return flows.

  20. Regression models for estimating concentrations of atrazine plus deethylatrazine in shallow groundwater in agricultural areas of the United States

    USGS Publications Warehouse

    Stackelberg, Paul E.; Barbash, Jack E.; Gilliom, Robert J.; Stone, Wesley W.; Wolock, David M.

    2012-01-01

    Tobit regression models were developed to predict the summed concentration of atrazine [6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine] and its degradate deethylatrazine [6-chloro-N-(1-methylethyl)-1,3,5,-triazine-2,4-diamine] (DEA) in shallow groundwater underlying agricultural settings across the conterminous United States. The models were developed from atrazine and DEA concentrations in samples from 1298 wells and explanatory variables that represent the source of atrazine and various aspects of the transport and fate of atrazine and DEA in the subsurface. One advantage of these newly developed models over previous national regression models is that they predict concentrations (rather than detection frequency), which can be compared with water quality benchmarks. Model results indicate that variability in the concentration of atrazine residues (atrazine plus DEA) in groundwater underlying agricultural areas is more strongly controlled by the history of atrazine use in relation to the timing of recharge (groundwater age) than by processes that control the dispersion, adsorption, or degradation of these compounds in the saturated zone. Current (1990s) atrazine use was found to be a weak explanatory variable, perhaps because it does not represent the use of atrazine at the time of recharge of the sampled groundwater and because the likelihood that these compounds will reach the water table is affected by other factors operating within the unsaturated zone, such as soil characteristics, artificial drainage, and water movement. Results show that only about 5% of agricultural areas have greater than a 10% probability of exceeding the USEPA maximum contaminant level of 3.0 μg L-1. These models are not developed for regulatory purposes but rather can be used to (i) identify areas of potential concern, (ii) provide conservative estimates of the concentrations of atrazine residues in deeper potential drinking water supplies, and (iii) set priorities

  1. Control of acid mine drainage using surfactants

    SciTech Connect

    Not Available

    1983-02-01

    This news sheet describes US Bureau of Mines work on the reduction or prevention of acid mine drainage from coal refuse piles and surface mines by inhibiting the growth of Thiobacillus ferrooxidans. It has been found that the direct application of a dilute surfactant or detergent solution to coal refuse piles or overburden can be an effective preventive measure or can reduce water treatment costs by controlling acid drainage at its source. Of the anionic surfactants tested to date, sodium lauryl sulphate appears to be the most effective. Alpha olefin sulphonate and alkyl benzene sulphonate are acceptable alternatives. The results of field trials are presented.

  2. Review of 555 cholecystectomies without drainage.

    PubMed

    Carpenter, W S; Kambouris, A A; Allaben, R D

    1978-04-01

    During a 10-year period, 555 cholecystectomies were performed without drainage of the gallbladder bed or subhepatic space. Six per cent of the patients had acute cholecystitis or hydrops of the gallbaldder and 11% had common duct exploration. Only in those patients with frank infection, spillage of obviously infected bile or in whom satisfactory closure of the gallbladder bed could not be accomplished was a drain used. Meticulous closure of the gallbladder bed was performed to minimize leakage of bile. The series was critically studied to evaluate complications, morbidity, mortality and hospital stay. It was concluded that drainage following cholecystectomy or choledochotomy can safely be omitted except for the indications mentioned.

  3. [Laparoscopic abdominal drainage by sterile destructive pancreatitis].

    PubMed

    Kuznetsov, N A; Rodoman, G V; Shalaeva, T I; Trefilova, O I; Sosikova, N L

    2009-01-01

    90 patients with acute pancreatitis were observed, in 60 of them laparoscopic drainage was performed. The procedure by sterile pancreatonecrosis is indicated only in presence of extent amount of exudate in abdominal cavity. Duration of draining the abdominal cavity should be strictly limited because of the high risk of septic complications. Contraindications for the abdominal drainage by acute necrotic pancreatitis are not only adhesions in the abdomen and shock state of the patient at the moment of procedure necessity, but also unstable hemodynamics in anamnesis and even by the arterial pressure downtrend.

  4. Effects of hydrology, watershed size, and agricultural practices on sediment yields in two river basins in Iowa and Mississippi

    USGS Publications Warehouse

    Merten, Gustavo Henrique; Welch, Heather L.; Tomer, M.D.

    2016-01-01

    The specific sediment yield (SSY) from watersheds is the result of the balance between natural, scale-dependent erosion and deposition processes, but can be greatly altered by human activities. In general, the SSY decreases along the course of a river as sediments are trapped in alluvial plains and other sinks. However, this relation between SSY and basin area can actually be an increasing one when there is a predominance of channel erosion relative to hillslope erosion. The US Geological Survey (USGS) conducted a study of suspended sediment in the Iowa River basin (IRB), Iowa, and the Yazoo River basin (YRB), Mississippi, from 2006 through 2008. Within each river basin, the SSY from four largely agricultural watersheds of various sizes (2.3 to 35,000 km2 [0.9 to 13,513 mi2]) was investigated. In the smallest watersheds, YRB sites had greater SSY compared to IRB sites due to higher rain erosivity, more erodible soils, more overland flow, and fluvial geomorphological differences. Watersheds in the YRB showed a steady decrease in SSY with increasing drainage basin area, whereas in the IRB, the maximum SSY occurred at the 30 to 500 km2 (11.6 to 193 mi2) scale. Subsurface tile drainage and limits to channel downcutting restrict the upstream migration of sediment sources in the IRB. Nevertheless, by comparing the SSY-basin size scaling relationships with estimated rates of field erosion under conservation and conventional tillage treatments reported in previous literature, we show evidence that the SSY-basin size relationship in both the IRB and YRB remain impacted by historical erosion rates that occurred prior to conservation efforts.

  5. Groundwater recharge and agricultural contamination

    USGS Publications Warehouse

    Böhlke, J.K.

    2002-01-01

    Agriculture has had direct and indirect effects on the rates and compositions of groundwater recharge and aquifer biogeochemistry. Direct effects include dissolution and transport of excess quantities of fertilizers and associated materials and hydrologic alterations related to irrigation and drainage. Some indirect effects include changes in water-rock reactions in soils and aquifers caused by increased concentrations of dissolved oxidants, protons, and major ions. Agrilcultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO3-, N2, Cl, SO42-, H+, P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well a wide variety of pesticides and other organic compounds. For reactive contaminants like NO3-, a combination of chemical, isotopic, and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. Groundwater records derived from multi-component hydrostratigraphic data can be used to quantify recharge rates and residence times of water and dissolved contaminants, document past variations in recharging contaminant loads, and identify natural contaminant-remediation processes. These data indicate that many of the world's surficial aquifers contain transient records of changing agricultural contamination from the last half of the 20th century. The transient agricultural groundwater signal has important implications for long-term trends and spatial heterogeneity in discharge.

  6. Temporal trends and relationships between groundwater and surface water nitrate concentrations in headwater agricultural catchments: what can we learn from a monitoring over 20 years?

    NASA Astrophysics Data System (ADS)

    Fovet, O.; Gascuel, C.; Faucheux, M.; Ruiz, L.; Aquilina, L.; Molenat, J.

    2012-04-01

    The intensification of agriculture during the 20th century led to strong issues on water quality related to nutrients enrichments in groundwater and surface water. In this context, Western France is an extreme case regarding to the high nitrate concentrations observed in rivers (around 7 mg N-NO3/l1 in average). In the early 90ies, an Environmental Research Observatory AgrHys has been created and instrumented to investigate the response time of hydro-chemical fluxes to landuse changes in agrohydrosystems. This observatory is part of a French Catchments Network (Critical Zone Observatory), and composed of two sites. Kervidy-Naizin monitoring has been recently analyzed to identify the effect of climatic factors on water quality, while we focus here on Kerbernez site. This site is composed of 5 first-order and adjacent catchments, less than 1 km^2, where land use agricultural practices have been recorded with precision. Hydrological, hydrochemical and climatic data were recorded over the last 20 years. Since 2001, the monitoring was extended to groundwater using piezometric measurements and chemical analyses. Previous studies [1] suggested that nitrate transport was essentially a transport limited process on this site. The long-term and extensive monitoring programs can help us understanding the effect of agricultural practices on nitrate concentration in streams. We reconsider this hypothesis 10 years later by analyzing if the streams nitrate concentrations reacted to the changes in agricultural practices. Different protocols of monitoring (manual vs. automatic measurements) are compared though the annual water fluxes at the outlet in order to estimate the incertitude on water discharge for such small streams. All the water balances computed were not equilibrated suggesting important subsurface flows. The high contribution of the shallow groundwater is confirmed by the hydrochemical data. Mean annual nitrate concentration in the drainage water is computed using two

  7. Mineralogical correlation of surficial sediment from area drainages with selected sedimentary interbeds at the Idaho National Engineering Laboratory, Idaho

    SciTech Connect

    Bartholomay, R.C.

    1990-08-01

    Ongoing research by the US Geological Survey at the INEL involves investigation of the migration of radioactive elements contained in low-level radioactive waste, hydrologic and geologic factors affecting waste movement, and geochemical factors that influence the chemical composition of the waste. Identification of the mineralogy of the Snake River Plain is needed to aid in the study of the hydrology and geochemistry of subsurface waste disposal. The US Geological Surveys project office at the Idaho National Engineering Laboratory, in cooperation with the US Department of Energy, used mineralogical data to correlate surficial sediment samples from the Big Lost River, Little Lost River, and Birch Greek drainages with selected sedimentary interbed core samples taken from test holes at the RWMC (Radioactive Waste Management Complex), TRA (Test Reactors Area), ICPP (Idaho Chemical Processing Plant), and TAN (Test Area North). Correlating the mineralogy of a particular present-day drainage area with a particular sedimentary interbed provides information on historical source of sediment for interbeds in and near the INEL. Mineralogical data indicate that surficial sediment samples from the Big Lost River drainage contained a larger amount of feldspar and pyroxene and a smaller amount of calcite and dolomite than samples from the Little Lost River and Birch Creek drainages. Mineralogical data from sedimentary interbeds at the RWMC, TRA, and ICPP correlate with surficial sediment of the present-day big Lost River drainage. Mineralogical data from a sedimentary interbed at TAN correlate with surficial sediment of the present-day Birch Creek drainage. 13 refs., 5 figs., 3 tabs.

  8. Wave-Based Subsurface Guide Star

    SciTech Connect

    Lehman, S K

    2011-07-26

    Astronomical or optical guide stars are either natural or artificial point sources located above the Earth's atmosphere. When imaged from ground-based telescopes, they are distorted by atmospheric effects. Knowing the guide star is a point source, the atmospheric distortions may be estimated and, deconvolved or mitigated in subsequent imagery. Extending the guide star concept to wave-based measurement systems to include acoustic, seismo-acoustic, ultrasonic, and radar, a strong artificial scatterer (either acoustic or electromagnetic) may be buried or inserted, or a pre-existing or natural sub-surface point scatterer may be identified, imaged, and used as a guide star to determine properties of the sub-surface volume. That is, a data collection is performed on the guide star and the sub-surface environment reconstructed or imaged using an optimizer assuming the guide star is a point scatterer. The optimization parameters are the transceiver height and bulk sub-surface background refractive index. Once identified, the refractive index may be used in subsequent reconstructions of sub-surface measurements. The wave-base guide star description presented in this document is for a multimonostatic ground penetrating radar (GPR) but is applicable to acoustic, seismo-acoustic, and ultrasonic measurement systems operating in multimonostatic, multistatic, multibistatic, etc., modes.

  9. [Transformation of Non-point Source Soluble Nitrogen in Simulated Drainage Ditch].

    PubMed

    Li, Qiang-kun; Song, Chang-ji; Hu, Ya-wei; Peng, Cong; Ma, Qiang; Jiang, Zheng-xi; Ju, Yi-rheng

    2016-02-15

    The drainage ditch has a compound ecosystem structure consisting of water, sediment and plants. Migration and transformation of the non-point source solute is important to study interception, control and management of agricultural non-point source pollution in the drainage ditch. Based on the experiment on static simulation of drainage ditches, the article used typical non-point source soluble nitrogen as an example to analyze the changing process of nitrogen content in water, sediment and reeds, and to study the effects of the sediment adsorption and desorption, reeds growth and death in different periods on nitrogen concentration in water. The article discussed nitrogen migration in water-sediment-reeds compound ecosystem and its influence on nitrogen concentration in water. The results showed that both adsorption and desorption in sediment and absorption and assimilation of reeds growth had effect on nitrogen concentration in water. The effect before October was reducing the nitrogen concentration in water, which was the process of nitrogen purification in water. After October, the nitrogen concentration in water increased and made it easy to form secondary nitrogen pollution. Meanwhile, the migration in the water-sediment-seeds ecosystem in simulated drainage ditch had close ties, any migration and transformation of nitrogen in a single medium or between different mediums would cause adjustment of nitrogen concentration in water.

  10. 24 CFR 3280.610 - Drainage systems.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... water seal trap (§ 3280.606(a)). (2) The drainage system shall be designed to provide an adequate circulation of air in all piping with no danger of siphonage, aspiration, or forcing of trap seals under... equipped with a water-tight cap or plug matching the drain outlet. The cap or plug shall be...

  11. 24 CFR 3280.610 - Drainage systems.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... water seal trap (§ 3280.606(a)). (2) The drainage system shall be designed to provide an adequate circulation of air in all piping with no danger of siphonage, aspiration, or forcing of trap seals under... equipped with a water-tight cap or plug matching the drain outlet. The cap or plug shall be...

  12. Systemic venous drainage: can we help Newton?

    PubMed

    Corno, Antonio F

    2007-06-01

    In recent years substantial progress occurred in the techniques of cardiopulmonary bypass, but the factor potentially limiting the flexibility of cardiopulmonary bypass remains the drainage of the systemic venous return. In the daily clinical practice of cardiac surgery, the amount of systemic venous return on cardiopulmonary bypass is directly correlated with the amount of the pump flow. As a consequence, the pump flow is limited by the amount of venous return that the pump is receiving. On cardiopulmonary bypass the amount of venous drainage depends upon the central venous pressure, the height differential between patient and inlet of the venous line into the venous reservoir, and the resistance in the venous cannula(s) and circuit. The factors determining the venous return to be taken into consideration in cardiac surgery are the following: (a) characteristics of the individual patient; (b) type of planned surgical procedure; (c) type of venous cannula(s); (d) type of circuit for cardiopulmonary bypass; (e) strategy of cardiopulmonary bypass; (f) use of accessory mechanical systems to increased the systemic venous return. The careful pre-operative evaluation of all the elements affecting the systemic venous drainage, including the characteristics of the individual patient and the type of required surgical procedure, the choice of the best strategy of cardiopulmonary bypass, and the use of the most advanced materials and tools, can provide a systemic venous drainage substantially better than what it would be allowed by the simple "Law of universal gravitation" by Isaac Newton.

  13. 24 CFR 3285.203 - Site Drainage.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Purpose. Drainage must be provided to direct surface water away from the home to protect against erosion of foundation supports and to prevent water build-up under the home, as shown in Figure to § 3285.203... tile and automatic sump pump system, must be provided to remove any water that may collect under...

  14. 24 CFR 3285.203 - Site Drainage.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... home. (c) All drainage must be diverted away from the home and must slope a minimum of one-half inch per foot away from the foundation for the first ten feet. Where property lines, walls, slopes, or other physical conditions prohibit this slope, the site must be provided with drains or swales...

  15. 24 CFR 3285.203 - Site Drainage.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... home. (c) All drainage must be diverted away from the home and must slope a minimum of one-half inch per foot away from the foundation for the first ten feet. Where property lines, walls, slopes, or other physical conditions prohibit this slope, the site must be provided with drains or swales...

  16. Prevention of acid drainage from stored coal

    SciTech Connect

    Olem, H.

    1983-01-01

    It was found that application of a 50-mg/l solution of the detergent sodium lauryl sulphate to a coal stockpile inhibited the activity of the bacteria causing acid formation and leaching and kept the drainage neutral for 60 days. The cost of a single application would be 0.4 cents/t of coal.

  17. GROUNDWATER IMPACTED BY ACID MINE DRAINAGE

    EPA Science Inventory

    The generation and release of acidic, metal-rich water from mine wastes continues to be an intractable environmental problem. Although the effects of acid mine drainage (AMD) are most evident in surface waters, there is an obvious need for developing cost-effective approaches fo...

  18. Drainage hydraulics of permeable friction courses

    NASA Astrophysics Data System (ADS)

    Charbeneau, Randall J.; Barrett, Michael E.

    2008-04-01

    This paper describes solutions to the hydraulic equations that govern flow in permeable friction courses (PFC). PFC is a layer of porous asphalt approximately 50 mm thick that is placed as an overlay on top of an existing conventional concrete or asphalt road surface to help control splash and hydroplaning, reduce noise, and enhance quality of storm water runoff. The primary objective of this manuscript is to present an analytical system of equations that can be used in design and analysis of PFC systems. The primary assumptions used in this analysis are that the flow can be modeled as one-dimensional, steady state Darcy-type flow and that slopes are sufficiently small so that the Dupuit-Forchheimer assumptions apply. Solutions are derived for cases where storm water drainage is confined to the PFC bed and for conditions where the PFC drainage capacity is exceeded and ponded sheet flow occurs across the pavement surface. The mathematical solutions provide the drainage characteristics (depth and residence time) as a function of rainfall intensity, PFC hydraulic conductivity, pavement slope, and maximum drainage path length.

  19. Reality named endoscopic ultrasound biliary drainage.

    PubMed

    Guedes, Hugo Gonçalo; Lopes, Roberto Iglesias; de Oliveira, Joel Fernandez; Artifon, Everson Luiz de Almeida

    2015-10-25

    Endoscopic ultrasound (EUS) is used for diagnosis and evaluation of many diseases of the gastrointestinal (GI) tract. In the past, it was used to guide a cholangiography, but nowadays it emerges as a powerful therapeutic tool in biliary drainage. The aims of this review are: outline the rationale for endoscopic ultrasound-guided biliary drainage (EGBD); detail the procedural technique; evaluate the clinical outcomes and limitations of the method; and provide recommendations for the practicing clinician. In cases of failed endoscopic retrograde cholangiopancreatography (ERCP), patients are usually referred for either percutaneous transhepatic biliary drainage (PTBD) or surgical bypass. Both these procedures have high rates of undesirable complications. EGBD is an attractive alternative to PTBD or surgery when ERCP fails. EGBD can be performed at two locations: transhepatic or extrahepatic, and the stent can be inserted in an antegrade or retrograde fashion. The drainage route can be transluminal, duodenal or transpapillary, which, again, can be antegrade or retrograde [rendezvous (EUS-RV)]. Complications of all techniques combined include pneumoperitoneum, bleeding, bile leak/peritonitis and cholangitis. We recommend EGBD when bile duct access is not possible because of failed cannulation, altered upper GI tract anatomy, gastric outlet obstruction, a distorted ampulla or a periampullary diverticulum, as a minimally invasive alternative to surgery or radiology.

  20. Calculation of exit gradients at drainage ditches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seepage gradients play an important role in the detachment of soil particles from the side walls of stream channels and drainage ditches. Most seepage studies have focused on water losses. Relatively few have addressed the determination of these gradients as causes of soil loss and incipient gully d...

  1. 24 CFR 3285.203 - Site Drainage.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Purpose. Drainage must be provided to direct surface water away from the home to protect against erosion of foundation supports and to prevent water build-up under the home, as shown in Figure to § 3285.203... tile and automatic sump pump system, must be provided to remove any water that may collect under...

  2. [Artificial drainage devices--history, indications].

    PubMed

    Barac, Ileana Ramona; Pop, Monica

    2012-01-01

    Glaucoma is a degenerative optic neuropathy progressive, multifactorial, which can lead to blindness. Blindness in patients with glaucoma is defined as visual field reduction below 10 degrees. Artificial drainage systems are a solution for refractory to medication, laser treatment or conventional surgery. Used by over 100 years, improved with good surgical technique and careful patient follow-up surgery, postoperative results are satisfactory.

  3. Late Pleistocene drainage systems beneath Delaware Bay

    USGS Publications Warehouse

    Knebel, H. J.; Circe, R.C.

    1988-01-01

    Analyses of an extensive grid of seismic-reflection profiles, along with previously published sedimentary data and geologic information from surrounding coastal areas, outline the ancestral drainage systems of the Delaware River beneath lower Delaware Bay. Major paleovalleys within these systems have southeast trends, relief of 10-35 m, widths of 1-8 km, and axial depths of 31-57 m below present sea level. The oldest drainage system was carved into Miocene sands, probably during the late Illinoian lowstand of sea level. It followed a course under the northern half of the bay, continued beneath the Cape May peninsula, and extended onto the present continental shelf. This system was buried by a transgressive sequence of fluvial, estuarine, and shallow-marine sediments during Sangamonian time. At the height of the Sangamonian sea-level transgression, littoral and nearshore processes built the Cape May peninsula southward over the northern drainage system and formed a contiguous submarine sedimentary ridge that extended partway across the present entrance to the bay. When sea level fell during late Wisconsinan time, a second drainage system was eroded beneath the southern half of the bay in response to the southerly shift of the bay mouth. This system, which continued across the shelf, was cut into Coastal Plain deposits of Miocene and younger age and included not only the trunk valley of the Delaware River but a large tributary valley formed by the convergence of secondary streams that drained the Delaware coastal area. During the Holocene rise of sea level, the southern drainage system was covered by a transgressive sequence of fluvial, estuarine, and paralic deposits that accumulated due to the passage of the estuarine circulation cell and to the landward and upward migration of coastal sedimentary environments. Some Holocene deposits have been scoured subsequently by strong tidal currents. The southward migration of the ancestral drainage systems beneath Delaware

  4. Physical modeling of transverse drainage mechanisms

    NASA Astrophysics Data System (ADS)

    Douglass, J. C.; Schmeeckle, M. W.

    2005-12-01

    Streams that incise across bedrock highlands such as anticlines, upwarps, cuestas, or horsts are termed transverse drainages. Their relevance today involves such diverse matters as highway and dam construction decisions, location of wildlife corridors, better-informed sediment budgets, and detailed studies into developmental histories of late Cenozoic landscapes. The transient conditions responsible for transverse drainage incision have been extensively studied on a case-by-case basis, and the dominate mechanisms proposed include: antecedence, superimposition, overflow, and piracy. Modeling efforts have been limited to antecedence, and such the specific erosional conditions required for transverse drainage incision, with respect to the individual mechanisms, remains poorly understood. In this study, fifteen experiments attempted to simulate the four mechanisms and constructed on a 9.15 m long, 2.1 m wide, and 0.45 m deep stream table. Experiments lasted between 50 and 220 minutes. The stream table was filled with seven tons of sediment consisting of a silt and clay (30%) and a fine to coarse sand (70%) mixture. The physical models highlighted the importance of downstream aggradation with regard to antecedent incision versus possible defeat and diversion. The overflow experiments indicate that retreating knickpoints across a basin outlet produce a high probability of downstream flooding when associated with a deep lake. Misters used in a couple of experiments illustrate a potential complication with regard to headward erosion driven piracy. Relatively level asymmetrically sloped ridges allow for the drainage divide across the ridge to retreat from headward erosion, but hindered when the ridge's apex undulates or when symmetrically sloped. Although these physical models cannot strictly simulate natural transverse drainages, the observed processes, their development over time, and resultant landforms roughly emulate their natural counterparts. Proposed originally from

  5. Topological Analysis of Urban Drainage Networks

    NASA Astrophysics Data System (ADS)

    Yang, Soohyun; Paik, Kyungrock; McGrath, Gavan; Rao, Suresh

    2016-04-01

    Urban drainage networks are an essential component of infrastructure, and comprise the aggregation of underground pipe networks carrying storm water and domestic waste water for eventual discharge to natural stream networks. Growing urbanization has contributed to rapid expansion of sewer networks, vastly increasing their complexity and scale. Importance of sewer networks has been well studied from an engineering perspective, including resilient management, optimal design, and malfunctioning impact. Yet, analysis of the urban drainage networks using complex networks approach are lacking. Urban drainage networks consist of manholes and conduits, which correspond to nodes and edges, analogous to junctions and streams in river networks. Converging water flows in these two networks are driven by elevation gradient. In this sense, engineered urban drainage networks share several attributes of flows in river networks. These similarities between the two directed, converging flow networks serve the basis for us to hypothesize that the functional topology of sewer networks, like river networks, is scale-invariant. We analyzed the exceedance probability distribution of upstream area for practical sewer networks in South Korea. We found that the exceedance probability distributions of upstream area follow power-law, implying that the sewer networks exhibit topological self-similarity. The power-law exponents for the sewer networks were similar, and within the range reported from analysis of natural river networks. Thus, in line with our hypothesis, these results suggest that engineered urban drainage networks share functional topological attributes regardless of their structural dissimilarity or different underlying network evolution processes (natural vs. engineered). Implications of these findings for optimal design of sewer networks and for modeling sewer flows will be discussed.

  6. 46 CFR 116.1110 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ARRANGEMENT Drainage and Watertight Integrity of Weather Decks § 116.1110 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel must...

  7. 46 CFR 178.410 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.410 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck...

  8. 46 CFR 116.1110 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ARRANGEMENT Drainage and Watertight Integrity of Weather Decks § 116.1110 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel must...

  9. 46 CFR 116.1110 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ARRANGEMENT Drainage and Watertight Integrity of Weather Decks § 116.1110 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel must...

  10. 46 CFR 116.1110 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... ARRANGEMENT Drainage and Watertight Integrity of Weather Decks § 116.1110 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel must...

  11. 46 CFR 178.410 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.410 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck...

  12. 46 CFR 178.430 - Drainage of well deck vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.430 Drainage of well deck vessels. (a) The weather deck on a well deck vessel must be watertight. (b) The area required on a...

  13. 46 CFR 178.430 - Drainage of well deck vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.430 Drainage of well deck vessels. (a) The weather deck on a well deck vessel must be watertight. (b) The area required on a...

  14. 46 CFR 178.430 - Drainage of well deck vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.430 Drainage of well deck vessels. (a) The weather deck on a well deck vessel must be watertight. (b) The area required on a...

  15. 46 CFR 178.430 - Drainage of well deck vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.430 Drainage of well deck vessels. (a) The weather deck on a well deck vessel must be watertight. (b) The area required on a...

  16. 46 CFR 178.410 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.410 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck...

  17. 46 CFR 178.430 - Drainage of well deck vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.430 Drainage of well deck vessels. (a) The weather deck on a well deck vessel must be watertight. (b) The area required on a...

  18. 46 CFR 178.410 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.410 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck...

  19. 46 CFR 178.410 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.410 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck...

  20. Ionic composition and nitrate in drainage water from fields fertilized with different nitrogen sources, middle swamp watershed, North Carolina, August 2000-August 2001

    USGS Publications Warehouse

    Harden, Stephen L.; Spruill, Timothy B.

    2004-01-01

    A study was conducted from August 2000 to August 2001 to characterize the influence of fertilizer use from different nitrogen sources on the quality of drainage water from 11 subsurface tile drains and 7 surface field ditches in a North Carolina Coastal Plain watershed. Agricultural fields receiving commercial fertilizer (conventional sites), swine lagoon effluent (spray sites), and wastewater-treatment plant sludge (sludge site) in the Middle Swamp watershed were investigated. The ionic composition of drainage water in tile drains and ditches varied depending on fertilizer source type. The dominant ions identified in water samples from tile drains and ditches include calcium, magnesium, sodium, chloride, nitrate, and sulfate, with tile drains generally having lower pH, low or no bicarbonates, and higher nitrate and chloride concentrations. Based on fertilizer source type, median nitrate-nitrogen concentrations were significantly higher at spray sites (32.0 milligrams per liter for tiles and 8.2 milligrams per liter for ditches) relative to conventional sites (6.8 milligrams per liter for tiles and 2.7 milligrams per liter for ditches). The median instantaneous nitrate-nitrogen yields also were significantly higher at spray sites (420 grams of nitrogen per hectare per day for tile drains and 15.6 grams of nitrogen per hectare per day for ditches) relative to conventional sites (25 grams of nitrogen per hectare per day for tile drains and 8.1 grams of nitrogen per hectare per day for ditches). The tile drain site where sludge is applied had a median nitrate-nitrogen concentration of 10.5 milligrams per liter and a median instantaneous nitrate-nitrogen yield of 93 grams of nitrogen per hectare per day, which were intermediate to those of the conventional and spray tile drain sites. Results from this study indicate that nitrogen loadings and subsequent edge-of-field nitrate-nitrogen yields through tile drains and ditches were significantly higher at sites receiving

  1. Microbial activities in deep subsurface environments

    SciTech Connect

    Phelps, T.J.; Raione, E.G.; White, D.C. |; Fliermans, C.B.

    1988-12-31

    Activities of microorganisms residing in terrestrial deep subsurface sediments were examined in forty-six sediment samples from three aseptically sampled boreholes. Radiolabeled time course experiments assessing in situ microbial activities were initiated within 30 minutes of core recovery. [{sup 14}C-1-] Acetate incorporation into lipids. [methyl-{sup 3}H-]thymidine incorporation into DNA, [{sup 14}C-2-]acetate and [{sup 14}C-U-]glucose mineralization in addition to microbial enrichment and enumeration studies were examined in surface and subsurface sediments. Surface soils contained the greatest biomass and activities followed by the shallow aquifer zones. Water saturated subsurface sediments exhibited three to four orders of magnitude greater activity and culturable microorganisms than the dense clay zones. Regardless of depth, sediments which contained more than 20% clays exhibited the lowest activities and culturable microorganisms.

  2. Anthropogenic effects on subsurface temperature in Bangkok

    NASA Astrophysics Data System (ADS)

    Taniguchi, M.

    2006-09-01

    Subsurface temperatures in Bangkok, where population and density increase rapidly, were analyzed to evaluate the effects of surface warming due to urbanization. The magnitude of surface warming evaluated from subsurface temperature in Bangkok was 1.7°C which agreed with meteorological data during the last 50 years. The depth apart from steady thermal gradient, which shows an indicator of the magnitude of surface warming due to additional heat from urbanization, was deeper at the center of the city than in the suburb areas of Bangkok. In order to separate surface warming effects into global warming effect and urbanization effect, analyses of subsurface temperature have been done depending on the distance from the city center. The results show that the expansion of urbanization in Bangkok reaches up to 80 km from the city center.

  3. Autonomous microexplosives subsurface tracing system final report.

    SciTech Connect

    Engler, Bruce Phillip; Nogan, John; Melof, Brian Matthew; Uhl, James Eugene; Dulleck, George R., Jr.; Ingram, Brian V.; Grubelich, Mark Charles; Rivas, Raul R.; Cooper, Paul W.; Warpinski, Norman Raymond; Kravitz, Stanley H.

    2004-04-01

    The objective of the autonomous micro-explosive subsurface tracing system is to image the location and geometry of hydraulically induced fractures in subsurface petroleum reservoirs. This system is based on the insertion of a swarm of autonomous micro-explosive packages during the fracturing process, with subsequent triggering of the energetic material to create an array of micro-seismic sources that can be detected and analyzed using existing seismic receiver arrays and analysis software. The project included investigations of energetic mixtures, triggering systems, package size and shape, and seismic output. Given the current absence of any technology capable of such high resolution mapping of subsurface structures, this technology has the potential for major impact on petroleum industry, which spends approximately $1 billion dollar per year on hydraulic fracturing operations in the United States alone.

  4. Urban heat island in the subsurface

    NASA Astrophysics Data System (ADS)

    Ferguson, Grant; Woodbury, Allan D.

    2007-12-01

    The urban heat island effect has received significant attention in recent years due to the possible effect on long-term meteorological records. Recent studies of this phenomenon have suggested that this may not be important to estimates of regional climate change once data are properly corrected. However, surface air temperatures within urban environments have significant variation, making correction difficult. In the current study, we examine subsurface temperatures in an urban environment and the surrounding rural area to help characterize the nature of this variability. The results of our study indicate that subsurface temperatures are linked to land-use and supports previous work indicating that the urban heat island effect has significant and complex spatial variability. In most situations, the relationship between subsurface and surface processes cannot be easily determined, indicating that previous studies that relying on such a linkage may require further examination.

  5. Subsurface Contaminants Focus Area annual report 1997

    SciTech Connect

    1997-12-31

    In support of its vision for technological excellence, the Subsurface Contaminants Focus Area (SCFA) has identified three strategic goals. The three goals of the SCFA are: Contain and/or stabilize contamination sources that pose an imminent threat to surface and ground waters; Delineate DNAPL contamination in the subsurface and remediate DNAPL-contaminated soils and ground water; and Remove a full range of metal and radionuclide contamination in soils and ground water. To meet the challenges of remediating subsurface contaminants in soils and ground water, SCFA funded more than 40 technologies in fiscal year 1997. These technologies are grouped according to the following product lines: Dense Nonaqueous-Phase Liquids; Metals and Radionuclides; Source Term Containment; and Source Term Remediation. This report briefly describes the SCFA 1997 technologies and showcases a few key technologies in each product line.

  6. MSTS - Multiphase Subsurface Transport Simulator theory manual

    SciTech Connect

    White, M.D.; Nichols, W.E.

    1993-05-01

    The US Department of Energy, through the Yucca Mountain Site Characterization Project Office, has designated the Yucca Mountain site in Nevada for detailed study as the candidate US geologic repository for spent nuclear fuel and high-level radioactive waste. Site characterization will determine the suitability of the Yucca Mountain site for the potential waste repository. If the site is determined suitable, subsequent studies and characterization will be conducted to obtain authorization from the Nuclear Regulatory Commission to construct the potential waste repository. A principal component of the characterization and licensing processes involves numerically predicting the thermal and hydrologic response of the subsurface environment of the Yucca Mountain site to the potential repository over a 10,000-year period. The thermal and hydrologic response of the subsurface environment to the repository is anticipated to include complex processes of countercurrent vapor and liquid migration, multiple-phase heat transfer, multiple-phase transport, and geochemical reactions. Numerical simulators based on mathematical descriptions of these subsurface phenomena are required to make numerical predictions of the thermal and hydrologic response of the Yucca Mountain subsurface environment The engineering simulator called the Multiphase Subsurface Transport Simulator (MSTS) was developed at the request of the Yucca Mountain Site Characterization Project Office to produce numerical predictions of subsurface flow and transport phenomena at the potential Yucca Mountain site. This document delineates the design architecture and describes the specific computational algorithms that compose MSTS. Details for using MSTS and sample problems are given in the {open_quotes}User`s Guide and Reference{close_quotes} companion document.

  7. Induction heaters used to heat subsurface formations

    DOEpatents

    Nguyen, Scott Vinh [Houston, TX; Bass, Ronald M [Houston, TX

    2012-04-24

    A heating system for a subsurface formation includes an elongated electrical conductor located in the subsurface formation. The electrical conductor extends between at least a first electrical contact and a second electrical contact. A ferromagnetic conductor at least partially surrounds and at least partially extends lengthwise around the electrical conductor. The electrical conductor, when energized with time-varying electrical current, induces sufficient electrical current flow in the ferromagnetic conductor such that the ferromagnetic conductor resistively heats to a temperature of at least about 300.degree. C.

  8. Apparatus for passive removal of subsurface contaminants

    DOEpatents

    Pemberton, Bradley E.; May, Christopher P.; Rossabi, Joseph

    1997-01-01

    An apparatus is provided which passively removes contaminated gases from a subsurface. The apparatus includes a riser pipe extending into a subsurface which has an exterior end in fluid communication with a valve. When well pressure is greater than atmospheric pressure, the valve opens to release contaminants into the atmosphere, and when well pressure is less than atmospheric pressure, the valve closes to prevent flow of air into the well. The valve assembly of the invention comprises a lightweight ball which is lifted from its valve seat with a slight pressure drop between the well and the atmosphere.

  9. Radar Soundings of the Subsurface of Mars

    NASA Technical Reports Server (NTRS)

    Picardi, Giovanni; Plaut, Jeffrey J.; Biccari, Daniela; Bombaci, Ornella; Calabrese, Diego; Cartacci, Marco; Cicchetti, Andrea; Clifford, Stephen M.; Edenhofer, Peter; Farrell, William M.; Federico, Costanzo; Frigeri, Alessandro; Gurnett, Donald A.; Hagfors, Tor; Heggy, Essam; Herique, Alain; Huff, Richard L.; Ivanov, Anton B.; Johnson, William T. K.; Jordan, Rolando L.; Kirchner, Donald L.; Kofman, Wlodek; Leuschen, Carlton J.; Nielsen, Erling; Orosei, Roberto

    2005-01-01

    The martian subsurface has been probed to kilometer depths by the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument aboard the Mars Express orbiter. Signals penetrate the polar layered deposits, probably imaging the base of the deposits. Data from the northern lowlands of Chryse Planitia have revealed a shallowly buried quasi-circular structure about 250 kilometers in diameter that is interpreted to be an impact basin. In addition, a planar reflector associated with the basin structure may indicate the presence of a low-loss deposit that is more than 1 kilometer thick.

  10. Subsurface Microbes Expanding the Tree of Life

    SciTech Connect

    Banfield, Jillian

    2015-05-11

    Jillian Banfield, Ph.D., UC Berkeley Professor and Berkeley Lab Earth Sciences Division staff scientist and long-time user of the DOE Joint Genome Institute’s resources shares her perspective on how the DOE JGI helps advance her research addressing knowledge gaps related to the roles of subsurface microbial communities in biogeochemical cycling. The video was filmed near the town of Rifle, Colorado at the primary field site for Phase I of the Subsurface Systems Scientific Focus Area 2.0 sponsored by the DOE Office of Biological and Environmental Research.

  11. Apparatus for passive removal of subsurface contaminants

    DOEpatents

    Pemberton, B.E.; May, C.P.; Rossabi, J.

    1997-06-24

    An apparatus is provided which passively removes contaminated gases from a subsurface. The apparatus includes a riser pipe extending into a subsurface which has an exterior end in fluid communication with a valve. When well pressure is greater than atmospheric pressure, the valve opens to release contaminants into the atmosphere, and when well pressure is less than atmospheric pressure, the valve closes to prevent flow of air into the well. The valve assembly of the invention comprises a lightweight ball which is lifted from its valve seat with a slight pressure drop between the well and the atmosphere. 7 figs.

  12. Heating systems for heating subsurface formations

    SciTech Connect

    Nguyen, Scott Vinh; Vinegar, Harold J.

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  13. Subsurface Microbes Expanding the Tree of Life

    ScienceCinema

    Banfield, Jillian

    2016-07-12

    Jillian Banfield, Ph.D., UC Berkeley Professor and Berkeley Lab Earth Sciences Division staff scientist and long-time user of the DOE Joint Genome Institute’s resources shares her perspective on how the DOE JGI helps advance her research addressing knowledge gaps related to the roles of subsurface microbial communities in biogeochemical cycling. The video was filmed near the town of Rifle, Colorado at the primary field site for Phase I of the Subsurface Systems Scientific Focus Area 2.0 sponsored by the DOE Office of Biological and Environmental Research.

  14. Water Drainage from Unsaturated Soils in a Centrifuge Permeameter

    NASA Astrophysics Data System (ADS)

    Ornelas, G.; McCartney, J.; Zhang, M.

    2013-12-01

    This study involves an analysis of water drainage from an initially saturated silt layer in a centrifuge permeameter to evaluate the hydraulic properties of the soil layer in unsaturated conditions up to the point where the water phase becomes discontinuous. These properties include the soil water retention curve (SWRC) and the hydraulic conductivity function (HCF). The hydraulic properties of unsaturated silt are used in soil-atmosphere interaction models that take into account the role of infiltration and evaporation of water from soils due to atmospheric interaction. These models are often applied in slope stability analyses, landfill cover design, aquifer recharge analyses, and agricultural engineering. The hydraulic properties are also relevant to recent research concerning geothermal heating and cooling, as they can be used to assess the insulating effects of soil around underground heat exchangers. This study employs a high-speed geotechnical centrifuge to increase the self-weight of a compacted silt specimen atop a filter plate. Under a centrifuge acceleration of N times earth's gravity, the concept of geometric similitude indicates that the water flow process in a small-scale soil layer will be similar to those in a soil layer in the field that is N times thicker. The centrifuge acceleration also results in an increase in the hydraulic gradient across the silt specimen, which causes water to flow out of the pores following Darcy's law. The drainage test was performed until the rate of liquid water flow out of the soil layer slowed to a negligible level, which corresponds to the transition point at which further water flow can only occur due to water vapor diffusion following Fick's law. The data from the drainage test in the centrifuge were used to determine the SWRC and HCF at different depths in the silt specimen, which compared well with similar properties defined using other laboratory tests. The transition point at which liquid water flow stopped (and

  15. Prairie stream water quality in sub-basins characterized by differing degrees of wetland drainage

    NASA Astrophysics Data System (ADS)

    Brunet, N. N.; Westbrook, C. J.

    2010-12-01

    The prairie pothole region is dotted with millions of pothole wetlands. These wetlands provide important habitat for numerous wildlife species. Potholes are small, shallow marshes that typically lack surface water connections and have been shown to trap nutrients, ions, and bacteria from catchment runoff. Approximately 70% of the potholes located in the Canadian prairies have been drained since 1900 to increase agricultural production; recently there have been renewed efforts to drain potholes. Wetland drainage has been shown to increase stream discharge and is perceived to impact downstream water quality as previously isolated wetlands become connected to streams via drainage ditches. Our objective was to determine the extent to which stream water quality was influenced by wetland drainage. We compared time series of water quality for four sub-basins of Smith Creek watershed, southeastern Saskatchewan. The stream drains into the Assiniboine River and then Lake Winnipeg where excessive N and P loadings are causing eutrophication. Wetland distribution in the sub-basins was historically similar, but recently the sub-basins have been subject to differing degrees of drainage (extreme, high, moderately-high, and low). Stream water sampling and discharge measurement occurred daily during peak flow (spring runoff) and weekly during low flows in 2009 at the outlet of each sub-basin. Export coefficients for nutrients, DOC, salts and bacteria were compared among sub-basins. The sub-basin characterized by extreme drainage (81% wetland reduction) had the largest nutrient and DOC export coefficients while the low drainage sub-basin (23% wetland reduction) had the lowest. Concentrations of TP and ortho-P were greater in the moderately-high and high drainage sub-basins than in the low drainage sub-basin during the snowmelt period. TP concentrations exceeded the Saskatchewan Watershed Authority Lake Stewardship Program objective of 0.1 mg/L. N concentrations were greatest in the

  16. Parameterization of Subsurface Hydraulic Properties Using a Hillslope Scale Field Experiment

    NASA Astrophysics Data System (ADS)

    Brooks, E. S.; Boll, J.

    2001-12-01

    Recent research on a 2 ha catchment having a Santa Series fragi-pan soil in the Eastern Palouse has indicated a large subsurface lateral flow component which drives saturation excess runoff. Bromide tracer studies indicated travel times up to 16 m/day in shallow subsurface lateral flow above the fragi-pan soil layer. In order to quantify the subsurface lateral flow in the catchment an 18 m x 30 m hillslope plot was isolated with tile drains and trenches lined with plastic. Subsurface lateral flow and surface runoff leaving the plot were measured continuously with tipping bucket flow gages. Perched water table fluctuations were measured at 12 hour intervals at three locations within the plot. Snow water equivalent data were typically collected weekly during the winter and more intensively during melt periods. Hourly meterologic data were collected at a weather station located at the catchment. A mass balance was conducted on the spring runoff to indicate percolation through the fragi-pan subsoil layer. Theoretical solutions to tile drainage on sloping lands were applied to the data to determine the lateral saturated hydraulic conductivity (Ksat) as a function of depth at the plot scale. Comparisons are made between soil core and soil survey vertical Ksat and the plot scale lateral Ksat. The lateral flow leaving the plot during the spring melt period was 88% of the total measured precipitation and snowmelt. Plot scale lateral Ksat was on average seven times the soil core and soil survey values. Vertical percolation rate through the fragi-pan was less than 0.1 mm/day. This research has implications for erosion and runoff generating processes in areas dominated by hillslope lateral flow.

  17. Subsurface clade of Geobacteraceae that predominates in a diversity of Fe(III)-reducing subsurface environments

    USGS Publications Warehouse

    Holmes, Dawn E.; O'Neil, Regina A.; Vrionis, Helen A.; N'Guessan, Lucie A.; Ortiz-Bernad, Irene; Larrahondo, Maria J.; Adams, Lorrie A.; Ward, Joy A.; Nicoll , Julie S.; Nevin, Kelly P.; Chavan, Milind A.; Johnson, Jessica P.; Long, Philip E.; Lovely, Derek R.

    2007-01-01

    There are distinct differences in the physiology of Geobacter species available in pure culture. Therefore, to understand the ecology of Geobacter species in subsurface environments, it is important to know which species predominate. Clone libraries were assembled with 16S rRNA genes and transcripts amplified from three subsurface environments in which Geobacter species are known to be important members of the microbial community: (1) a uranium-contaminated aquifer located in Rifle, CO, USA undergoing in situ bioremediation; (2) an acetate-impacted aquifer that serves as an analog for the long-term acetate amendments proposed for in situ uranium bioremediation and (3) a petroleum-contaminated aquifer in which Geobacter species play a role in the oxidation of aromatic hydrocarbons coupled with the reduction of Fe(III). The majority of Geobacteraceae 16S rRNA sequences found in these environments clustered in a phylogenetically coherent subsurface clade, which also contains a number of Geobacter species isolated from subsurface environments. Concatamers constructed with 43 Geobacter genes amplified from these sites also clustered within this subsurface clade. 16S rRNA transcript and gene sequences in the sediments and groundwater at the Rifle site were highly similar, suggesting that sampling groundwater via monitoring wells can recover the most active Geobacter species. These results suggest that further study of Geobacter species in the subsurface clade is necessary to accurately model the behavior of Geobacter species during subsurface bioremediation of metal and organic contaminants.

  18. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Ventilation and drainage. 27.1187 Section... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Powerplant Fire Protection § 27.1187 Ventilation... for ventilation and drainage of flammable fluids. The drainage means must be— (a) Effective...

  19. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Ventilation and drainage. 27.1187 Section... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Powerplant Fire Protection § 27.1187 Ventilation... for ventilation and drainage of flammable fluids. The drainage means must be— (a) Effective...

  20. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Ventilation and drainage. 27.1187 Section... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Powerplant Fire Protection § 27.1187 Ventilation... for ventilation and drainage of flammable fluids. The drainage means must be— (a) Effective...

  1. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ventilation and drainage. 27.1187 Section... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Powerplant Fire Protection § 27.1187 Ventilation... for ventilation and drainage of flammable fluids. The drainage means must be— (a) Effective...

  2. 14 CFR 27.1187 - Ventilation and drainage.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Ventilation and drainage. 27.1187 Section... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Powerplant Fire Protection § 27.1187 Ventilation... for ventilation and drainage of flammable fluids. The drainage means must be— (a) Effective...

  3. 46 CFR 171.155 - Drainage of an open boat.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Drainage of an open boat. 171.155 Section 171.155 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.155 Drainage of an open boat....

  4. 46 CFR 171.155 - Drainage of an open boat.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Drainage of an open boat. 171.155 Section 171.155 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.155 Drainage of an open boat....

  5. 46 CFR 178.420 - Drainage of cockpit vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Drainage of cockpit vessels. 178.420 Section 178.420 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.420 Drainage of...

  6. 46 CFR 171.155 - Drainage of an open boat.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Drainage of an open boat. 171.155 Section 171.155 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.155 Drainage of an open boat....

  7. 46 CFR 171.155 - Drainage of an open boat.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Drainage of an open boat. 171.155 Section 171.155 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.155 Drainage of an open boat....

  8. 46 CFR 178.420 - Drainage of cockpit vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Drainage of cockpit vessels. 178.420 Section 178.420 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.420 Drainage of...

  9. 46 CFR 178.440 - Drainage of open boats.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Drainage of open boats. 178.440 Section 178.440 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.440 Drainage of open boats. The...

  10. 46 CFR 178.420 - Drainage of cockpit vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Drainage of cockpit vessels. 178.420 Section 178.420 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.420 Drainage of...

  11. 46 CFR 171.155 - Drainage of an open boat.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Drainage of an open boat. 171.155 Section 171.155 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.155 Drainage of an open boat....

  12. 46 CFR 178.440 - Drainage of open boats.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Drainage of open boats. 178.440 Section 178.440 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.440 Drainage of open boats. The...

  13. 46 CFR 178.440 - Drainage of open boats.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Drainage of open boats. 178.440 Section 178.440 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.440 Drainage of open boats. The...

  14. 46 CFR 178.440 - Drainage of open boats.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Drainage of open boats. 178.440 Section 178.440 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.440 Drainage of open boats. The...

  15. 46 CFR 178.440 - Drainage of open boats.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Drainage of open boats. 178.440 Section 178.440 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.440 Drainage of open boats. The...

  16. 46 CFR 178.420 - Drainage of cockpit vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Drainage of cockpit vessels. 178.420 Section 178.420 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.420 Drainage of...

  17. 46 CFR 178.420 - Drainage of cockpit vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Drainage of cockpit vessels. 178.420 Section 178.420 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.420 Drainage of...

  18. Structural analyses of a rigid pavement overlaying a sub-surface void

    NASA Astrophysics Data System (ADS)

    Adam, Fatih Alperen

    Pavement failures are very hazardous for public safety and serviceability. These failures in pavements are mainly caused by subsurface voids, cracks, and undulation at the slab-base interface. On the other hand, current structural analysis procedures for rigid pavement assume that the slab-base interface is perfectly planar and no imperfections exist in the sub-surface soil. This assumption would be violated if severe erosion were to occur due to inadequate drainage, thermal movements, and/or mechanical loading. Until now, the effect of erosion was only considered in the faulting performance model, but not with regards to transverse cracking at the mid-slab edge. In this research, the bottom up fatigue cracking potential, caused by the combined effects of wheel loading and a localized imperfection in the form of a void below the mid-slab edge, is studied. A robust stress and surface deflection analysis was also conducted to evaluate the influence of a sub-surface void on layer moduli back-calculation. Rehabilitative measures were considered, which included a study on overlay and fill remediation. A series regression of equations was proposed that provides a relationship between void size, layer moduli stiffness, and the overlay thickness required to reduce the stress to its original pre-void level. The effect of the void on 3D pavement crack propagation was also studied under a single axle load. The amplifications to the stress intensity was shown to be high but could be mitigated substantially if stiff material is used to fill the void and impede crack growth. The pavement system was modeled using the commercial finite element modeling program Abaqus RTM. More than 10,000 runs were executed to do the following analysis: stress analysis of subsurface voids, E-moduli back-calculation of base layer, pavement damage calculations of Beaumont, TX, overlay thickness estimations, and mode I crack analysis. The results indicate that the stress and stress intensity are, on

  19. Saturation dependence of the streaming potential during drainage and imbibition

    NASA Astrophysics Data System (ADS)

    Vinogradov, J.; Leinov, E.; Jackson, M.

    2012-12-01

    The rock pore space in many subsurface settings is saturated with water and one or more immiscible fluid phases; examples include NAPLs in contaminated aquifers, supercritical CO2 during sequestration in deep saline aquifers, the vadose zone, and hydrocarbon reservoirs. To interpret spontaneous potential measurements for groundwater flow and hydraulic properties in these settings requires an understanding of the saturation dependence of the streaming potential. Vinogradov and Jackson [2011] recently reported measurements of the streaming potential during drainage and, for the first time, imbibition in sandstone plugs saturated with water and either undecane or nitrogen. However, they reported effective values of the streaming potential coupling coefficient (C) at partial saturation (Sw), because Sw in the plugs was not uniform during drainage or imbibition. The aim of this study is to determine the true value of C as a function of Sw. We use a three-step approach in which hydraulic and electrical parameters are determined using numerical simulation and either Nelder-Mead simplex unconstrained optimisation or Active-set constrained optimisation algorithm. In the first step, we determine the saturation dependence of the relative permeability and capillary pressure, assuming these are simple exponential functions of Sw (Corey-type) and using an objective function which is a weighted average of the measured (i) pressure drop across the plug, (ii) liquid rate flowing out of the plug, and (iii) fraction of water flowing out of the plug. In the second, we determine the saturation dependence of the electrical conductivity, using the measured conductivity of the plug as the objective function. In the final step, we determine the saturation dependence of the streaming potential, using the measured streaming potential across the plug as the objective function. We obtain a good match between simulated and measured values of C, and find that it (i) exhibits hysteresis, (ii) can

  20. Is Europa's Subsurface Water Ocean Warm?

    NASA Technical Reports Server (NTRS)

    Melosh, H. J.; Ekholm, A. G.; Showman, A. P.; Lorenz, R. D.

    2002-01-01

    Europa's subsurface water ocean may be warm: that is, at the temperature of water's maximum density. This provides a natural explanation of chaos melt-through events and leads to a correct estimate of the age of its surface. Additional information is contained in the original extended abstract.

  1. Lateral gene transfer in the subsurface

    SciTech Connect

    Barkay, Tamar; Sobecky, Patricia

    2007-08-27

    Lateral gene transfer (LGT) is an important adaptive mechanism among prokaryotic organisms. This mechanism is particularly important for the response of microorganisms to changing environmental conditions because it facilitates the transfer of a large number of genes and their rapid expression. Together the transferred genes promote rapid genetic and metabolic changes that may enhance survival to newly established and sometimes hostile environmental conditions. The goal of our project was to examine if and how LGT enhances microbial adaptation to toxic heavy metals in subsurface environments that had been contaminated by mixed wastes due to activities associated with the production of nuclear energy and weapons. This task has been accomplished by dividing the project to several sub-tasks. Thus, we: (1) Determined the level of resistance of subsurface bacterial isolates to several toxic metals, all identified as pollutants of concern in subsurface environments; (2) Designed, tested, and applied, a molecular approach that determined whether metal resistance genes had evolved by LGT among subsurface bacteria; and (3) Developed a DNA hybridization array for the identification of broad host range plasmids and of metal resistance plasmids. The results are briefly summarized below with references to published papers and manuscripts in preparation where details about our research can be found. Additional information may be found in copies of our published manuscripts and conference proceedings, and our yearly reports that were submitted through the RIMS system.

  2. Irrigation strategies using subsurface drip irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsurface drip irrigation (SDI) is practiced on approximately 60,000 ha in the Texas High Plains region of the USA. Adoption of SDI continues to increase in the region. This has been attributed to record drought in Texas and the US Southwest in recent years, declining irrigation well yields, and ev...

  3. BIODEGRADATION OF ATRAZINE IN SUBSURFACE ENVIRONMENTS

    EPA Science Inventory

    The pesticide atrazine is frequently detected in ground water, including ground water used as drinking water. Little information is available on the fate of atrazine in the subsurface, including its biodegradability. The objectives of this study were to evaluate the biodegradabil...

  4. Biomarker Preservation Potential of Subsurface Ecosystems

    NASA Astrophysics Data System (ADS)

    Onstott, T. C.; Harris, R. L.; Sherwood Lollar, B.; Pedersen, K. A.; Colwell, F. S.; Pfiffner, S. M.; Phelps, T. J.; Kieft, T. L.; Bakermans, C.

    2016-05-01

    If surface life emerged on Mars it may have succumbed to a Gaian bottleneck, whereas subsurface life would have continued to grow and evolve sheltered in rocks with sub-freezing saline pore water and their remains preserved in excavated rock.

  5. Characterization of imidacloprid availability in subsurface soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Degradation and sorption/desorption are the most important processes affecting the leaching of pesticides through soil because they control the amount of pesticide available for transport. Once pesticides move past the surface soil layers, variations in subsurface soil physical, chemical, and biolog...

  6. Methods for forming long subsurface heaters

    DOEpatents

    Kim, Dong Sub

    2013-09-17

    A method for forming a longitudinal subsurface heater includes longitudinally welding an electrically conductive sheath of an insulated conductor heater along at least one longitudinal strip of metal. The longitudinal strip is formed into a tubular around the insulated conductor heater with the insulated conductor heater welded along the inside surface of the tubular.

  7. Acid drainage from coal mining: Effect on paddy soil and productivity of rice.

    PubMed

    Choudhury, Burhan U; Malang, Akbar; Webster, Richard; Mohapatra, Kamal P; Verma, Bibhash C; Kumar, Manoj; Das, Anup; Islam, Mokidul; Hazarika, Samarendra

    2017-04-01

    Overburden and acid drainage from coal mining is transforming productive agricultural lands to unproductive wasteland in some parts of Northeast India. We have investigated the adverse effects of acid mine drainage on the soil of rice paddy and productivity by comparing them with non-mined land and abandoned paddy fields of Jaintia Hills in Northeast India. Pot experiments with a local rice cultivar (Myngoi) as test crop evaluated biological productivity of the contaminated soil. Contamination from overburden and acid mine drainage acidified the soil by 0.5 pH units, increased the exchangeable Al(3+) content 2-fold and its saturation on clay complexes by 53%. Available sulfur and extractable heavy metals, namely Fe, Mn and Cu increased several-fold in excess of critical limits, while the availability of phosphorus, potassium and zinc contents diminished by 32-62%. The grain yield of rice was 62% less from fields contaminated with acid mine drainage than from fields that have not suffered. Similarly, the amounts of vegetation, i.e. shoots and roots, in pots filled with soil from fields that received acid mine drainage were 59-68% less than from uncontaminated land (average shoot weight: 7.9±2.12gpot(-1); average root weight: 3.40±1.15gpot(-1)). Paddy fields recovered some of their productivity 4years after mining ceased. Step-wise multiple regression analysis affirmed that shoot weight in the pots and grain yield in field were significantly (p<0.01) and positively influenced by the soil's pH and its contents of K, N and Zn, while concentration of S in excess of threshold limits in contaminated soil significantly (p<0.01) reduced the weight of shoots in the pots and grain yield in the field.

  8. Application of geophysics to acid mine drainage investigations. Volume 2. Site investigations

    SciTech Connect

    Custis, K.

    1994-09-01

    The report describes geophysical field investigations undertaken to evaluate the utility of surface geophysical techniques in detecting and monitoring groundwater pollution from mine waste in the Western United States. The document addresses results of investigations at Spenceville Copper Mine, Leviathan Sulfur Mine, Iron Mountain Copper Mine, and Walker Copper Mine. Methods used in the field investigations included conventional D.C. resistivity, electromagnetic, self potential, and magnetic. It was found that the source and extent of acid mine drainage can be identified, known groundwater flow paths correlate well with geophysical anomalies, subsurface layering of mine waste piles can be mapped with some geophysical methods, and leakage from waste impoundments is detectable by some surface geophysical methods. The document includes maps, charts, and tables.

  9. Thermokarst lakes, drainage, and drained basins

    USGS Publications Warehouse

    Grosse, G.; Jones, B.; Arp, C.; Shroder, John F.

    2013-01-01

    Thermokarst lakes and drained lake basins are widespread in Arctic and sub-Arctic permafrost lowlands with ice-rich sediments. Thermokarst lake formation is a dominant mode of permafrost degradation and is linked to surface disturbance, subsequent melting of ground ice, surface subsidence, water impoundment, and positive feedbacks between lake growth and permafrost thaw, whereas lake drainage generally results in local permafrost aggradation. Thermokarst lakes characteristically have unique limnological, morphological, and biogeochemical characteristics that are closely tied to cold-climate conditions and permafrost properties. Thermokarst lakes also have a tendency toward complete or partial drainage through permafrost degradation and erosion. Thermokarst lake dynamics strongly affect the development of landscape geomorphology, hydrology, and the habitat characteristic of permafrost lowlands.

  10. Flood Response Along a Drainage Network

    NASA Astrophysics Data System (ADS)

    Meierdiercks, K. L.; Smith, J. A.; Miller, A. J.; Baeck, M.

    2007-12-01

    Flooding in urban areas is complex. As water overtops stream banks, it comes into contact with structural obstacles on the land surface, such as bridge constrictions, that dominate flow pathways. Furthermore, at small, or local, spatial scales, other hydraulic controls such as pipe surcharge and stormwater management ponds play a significant role in flood response. A major obstacle towards a better understanding of how these controls impact flood response is the scarcity of data available to characterize them. One watershed where both hydraulic and hydrologic data is available is the Dead Run watershed in Metropolitan Baltimore, Maryland. Dead Run is a research watershed of the Baltimore Ecosystem Study (BES), part of the Long Term Ecological Research network established by the National Science Foundation. Dead Run geospatial data is available through the BES and Baltimore County; hydrologic data was collected by the authors during field campaigns in the 2003-2005 field seasons; and hydraulic information including storm drain pipes, stormwater management ponds, and bridge constrictions was digitized by the author. The availability of this data in Dead Run allows us to detail not only the impact of impervious surfaces and hydrologic forcing on flood response, but also structural aspects of the urban drainage network. In this study, we integrate the three types of observations - geospatial, hydrologic, and hydraulic - to characterize drainage network structure along Dead Run's tributaries. We use these characterizations and the Environmental Protection Agency's Stormwater Management Model (EPA SWMM) to estimate the 10- and 100-year floods over the drainage network. Analyses focus on two extreme floods in Dead Run: the 7 July 2004 and 28 June 2005 events. Results highlight the importance of incorporating drainage network structure into the models we use to predict flooding in urban environments.

  11. Subsurface barrier verification technologies, informal report

    SciTech Connect

    Heiser, J.H.

    1994-06-01

    One of the more promising remediation options available to the DOE waste management community is subsurface barriers. Some of the uses of subsurface barriers include surrounding and/or containing buried waste, as secondary confinement of underground storage tanks, to direct or contain subsurface contaminant plumes and to restrict remediation methods, such as vacuum extraction, to a limited area. To be most effective the barriers should be continuous and depending on use, have few or no breaches. A breach may be formed through numerous pathways including: discontinuous grout application, from joints between panels and from cracking due to grout curing or wet-dry cycling. The ability to verify barrier integrity is valuable to the DOE, EPA, and commercial sector and will be required to gain full public acceptance of subsurface barriers as either primary or secondary confinement at waste sites. It is recognized that no suitable method exists for the verification of an emplaced barrier`s integrity. The large size and deep placement of subsurface barriers makes detection of leaks challenging. This becomes magnified if the permissible leakage from the site is low. Detection of small cracks (fractions of an inch) at depths of 100 feet or more has not been possible using existing surface geophysical techniques. Compounding the problem of locating flaws in a barrier is the fact that no placement technology can guarantee the completeness or integrity of the emplaced barrier. This report summarizes several commonly used or promising technologies that have been or may be applied to in-situ barrier continuity verification.

  12. Drainage and Stratification Kinetics of Foam Films

    NASA Astrophysics Data System (ADS)

    Zhang, Yiran; Sharma, Vivek

    2014-03-01

    Baking bread, brewing cappuccino, pouring beer, washing dishes, shaving, shampooing, whipping eggs and blowing bubbles all involve creation of aqueous foam films. Foam lifetime, drainage kinetics and stability are strongly influenced by surfactant type (ionic vs non-ionic), and added proteins, particles or polymers modify typical responses. The rate at which fluid drains out from a foam film, i.e. drainage kinetics, is determined in the last stages primarily by molecular interactions and capillarity. Interestingly, for certain low molecular weight surfactants, colloids and polyelectrolyte-surfactant mixtures, a layered ordering of molecules, micelles or particles inside the foam films leads to a stepwise thinning phenomena called stratification. Though stratification is observed in many confined systems including foam films containing particles or polyelectrolytes, films containing globular proteins seem not to show this behavior. Using a Scheludko-type cell, we experimentally study the drainage and stratification kinetics of horizontal foam films formed by protein-surfactant mixtures, and carefully determine how the presence of proteins influences the hydrodynamics and thermodynamics of foam films.

  13. Numerical simulations of drainage flows on Mars

    NASA Technical Reports Server (NTRS)

    Parish, Thomas R.; Howard, Alan D.

    1992-01-01

    Data collected by Viking Landers have shown that the meteorology of the near surface Martian environment is analogous to desertlike terrestrial conditions. Geological evidence such as dunes and frost streaks indicate that the surface wind is a potentially important factor in scouring of the martian landscape. In particular, the north polar basin shows erosional features that suggest katabatic wind convergence into broad valleys near the margin of the polar cap. The pattern of katabatic wind drainage off the north polar cap is similar to that observed on Earth over Antarctica or Greenland. The sensitivity is explored of Martian drainage flows to variations in terrain slope and diurnal heating using a numerical modeling approach. The model used is a 2-D sigma coordinate primitive equation system that has been used for simulations of Antarctic drainage flows. Prognostic equations include the flux forms of the horizontal scalar momentum equations, temperature, and continuity. Parameterization of both longwave (terrestrial) and shortwave (solar) radiation is included. Turbulent transfer of heat and momentum in the Martian atmosphere remains uncertain since relevant measurements are essentially nonexistent.

  14. Drawdown behavior of gravity drainage wells

    SciTech Connect

    Aasen, J.A.; Ramey, H.J. Jr.

    1993-10-01

    An analytical solution for drawdown in gravity drainage wells is developed. The free-surface flow is viewed as incompressible, and anisotropy effects are included. The well is a line source well, and the reservoir is infinitely large. The model is valid for small drawdowns. The uniform wellbore potential inner boundary condition is modelled using the proper Green`s function. The discontinuity at the wellbore is solved by introducing a finite skin radius, and the formulation produces a seepage face. The calculated wellbore flux distribution and wellbore pressures are in fair agreement with results obtained using a numerical gravity drainage simulator. Three distinct flow periods are observed. The wellbore storage period is caused by the moving liquid level, and the duration is short. During the long intermediate flow period, the wellbore pressure is nearly constant. In this period the free surface moves downwards, and the liquid is produced mainly by vertical drainage. At long times the semilog straight line appears. The confined liquid solutions by Theis (1935) and van Everdingen and Hurst (1949) may be used during the pseudoradial flow period if the flowrate is low. New type curves are presented that yield both vertical and horizontal permeabilities.

  15. Channelized subglacial drainage over a deformable bed

    USGS Publications Warehouse

    Walder, J.S.; Fowler, A.

    1994-01-01

    We develop theoretically a description of a possible subglacial drainage mechanism for glaciers and ice sheets moving over saturated, deformable till. The model is based on the plausible assumption that flow of water in a thin film at the ice-till interface is unstable to the formation of a channelized drainage system, and is restricted to the case in which meltwater cannot escape through the till to an underlying aquifer. In describing the physics of such channelized drainage, we have generalized and extended Rothlisberger's model of channels cut into basal ice to include "canals' cut into the till, paying particular attention to the role of sediment properties and the mechanics of sediment transport. We show that sediment-floored Rothlisberger (R) channels can exist for high effective pressures, and wide, shallow, ice-roofed canals cut into the till for low effective pressures. Canals should form a distributed, non-arborescent system, unlike R channels. Geologic evidence derived from land forms and deposits left by the Pleistocene ice sheets in North America and Europe is consistent with predictions of the model. -from Authors

  16. Hydrologic Response Differences Between Drainage Network Classifications

    NASA Astrophysics Data System (ADS)

    Coleman, M. L.; Gironas, J. A.; Niemann, J. D.

    2013-12-01

    Basin drainage networks have been grouped into classifications such as dendritic, parallel, pinnate, rectangular and trellis based on their planform structures. While it has long been known that the size and shape of a drainage basin affect its hydrologic response to precipitation events, the effects of the network organization have not been investigated as extensively. The objective of this work is to simulate and analyze the instantaneous unit hydrographs (IUHs) and hydrologic responses of networks from different classifications for potential systematic differences between the classifications. That goal is accomplished by calculating the IUH for ten previously-classified basins of each network type listed above using a spatially-distributed travel time (SDTT) model applied to the outlet flow length distributions (i.e., width functions) of each drainage network. We find that the width functions, IUHs and the resulting hydrologic responses of the different network classifications are each largely distinguishable from one another based on statistical tests of their moments. Additionally, we find that the differences in hydrologic responses are at least partially independent of the differences in the basin vertical characteristics, as represented by the slope-area relationships. The results indicate that network classification-dependent inputs to semi-distributed rainfall-runoff models could improve model performance.

  17. Modeling of subglacial hydrological development following rapid supraglacial lake drainage

    PubMed Central

    Dow, C F; Kulessa, B; Rutt, I C; Tsai, V C; Pimentel, S; Doyle, S H; van As, D; Lindbäck, K; Pettersson, R; Jones, G A; Hubbard, A

    2015-01-01

    The rapid drainage of supraglacial lakes injects substantial volumes of water to the bed of the Greenland ice sheet over short timescales. The effect of these water pulses on the development of basal hydrological systems is largely unknown. To address this, we develop a lake drainage model incorporating both (1) a subglacial radial flux element driven by elastic hydraulic jacking and (2) downstream drainage through a linked channelized and distributed system. Here we present the model and examine whether substantial, efficient subglacial channels can form during or following lake drainage events and their effect on the water pressure in the surrounding distributed system. We force the model with field data from a lake drainage site, 70 km from the terminus of Russell Glacier in West Greenland. The model outputs suggest that efficient subglacial channels do not readily form in the vicinity of the lake during rapid drainage and instead water is evacuated primarily by a transient turbulent sheet and the distributed system. Following lake drainage, channels grow but are not large enough to reduce the water pressure in the surrounding distributed system, unless preexisting channels are present throughout the domain. Our results have implications for the analysis of subglacial hydrological systems in regions where rapid lake drainage provides the primary mechanism for surface-to-bed connections. Key Points Model for subglacial hydrological analysis of rapid lake drainage events Limited subglacial channel growth during and following rapid lake drainage Persistence of distributed drainage in inland areas where channel growth is limited PMID:26640746

  18. OPEN DRAINAGE VERSUS PERCUTANEOUS DRAINAGE IN THE TREATMENT OF TROPICAL PYOMYOSITIS. PROSPECTIVE AND RANDOMIZED STUDY

    PubMed Central

    Palacio, Evandro Pereira; Rizzi, Nívea Gitahy; Reinas, Gustavo Serra; Júnior, Melvis Michiuti; Júnior, Alcides Durigan; Mizobuchi, Roberto Ryuiti; Yanasse, Ricardo Hideki; da Silva, Marcos Vinícius Muriano; Branco, Rodrigo Borsatto; Galbiatti, José Antônio

    2015-01-01

    Objective: To compare the results from treating tropical pyomyositis through percutaneous drainage of abscesses versus open surgical drainage of abscesses, by means of a randomized prospective study. Methods: Twenty-five patients with tropical pyomyositis (Chiedozi grade II) were included in this study. They were randomized into two groups: group A (n = 13), treated with antibiotics and open drainage of the abscesses; and group B (n = 12), treated with antibiotics and percutaneous drainage of the abscesses. Results: The mean age was 35.3 years (± 19.2) in group A and 30.1 years (± 9) in group B (p = 0.41). There were eight female patients (61.5%) and five male patients (38.5%) in group A; in group B, three were female (25%) and nine were male (75%) (p = 0.11). Staphylococcus aureus was the microorganism most frequently found (72%). The mean hospital stay in group A was 12.7 days (± 2.3), and in group B, 10.6 days (± 1.6) (p = 0.01). The mean duration of antibiotic use in group A was 12.2 days (± 2.3), and in group B, 10.1 days (± 1.5) (p = 0.02). Conclusion: Percutaneous drainage of the abscesses, in association with antibiotic therapy, is an efficient treatment method for tropical pyomyositis grade II, with shorter antibiotic use and hospital stay for patients. PMID:27022550

  19. Vocational Agriculture Handbook for Agriculture Cooperative Training.

    ERIC Educational Resources Information Center

    Texas A and M Univ., College Station. Vocational Instructional Services.

    This handbook was designed to assist school administrators, vocational administrators, vocational agricultural teachers, and area consultants of vocational agriculture in developing, implementing, and improving an agricultural cooperative training program (especially in Texas). The handbook, which presents information in a narrative format,…

  20. Using GIS and logistic regression to estimate agricultural chemical concentrations in rivers of the midwestern USA

    USGS Publications Warehouse

    Battaglin, W.A.

    1996-01-01

    Agricultural chemicals (herbicides, insecticides, other pesticides and fertilizers) in surface water may constitute a human health risk. Recent research on unregulated rivers in the midwestern USA documents that elevated concentrations of herbicides occur for 1-4 months following application in spring and early summer. In contrast, nitrate concentrations in unregulated rivers are elevated during the fall, winter and spring. Natural and anthropogenic variables of river drainage basins, such as soil permeability, the amount of agricultural chemicals applied or percentage of land planted in corn, affect agricultural chemical concentrations in rivers. Logistic regression (LGR) models are used to investigate relations between various drainage basin variables and the concentration of selected agricultural chemicals in rivers. The method is successful in contributing to the understanding of agricultural chemical concentration in rivers. Overall accuracies of the best LGR models, defined as the number of correct classifications divided by the number of attempted classifications, averaged about 66%.