10 CFR 36.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... means a facility that uses radioactive sealed sources for the irradiation of objects or materials and in... in which both the sealed source and the area subject to irradiation are contained within a device and... irradiator in which the irradiations occur in air in areas potentially accessible to personnel and in which...

10 CFR 36.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... means a facility that uses radioactive sealed sources for the irradiation of objects or materials and in... in which both the sealed source and the area subject to irradiation are contained within a device and... irradiator in which the irradiations occur in air in areas potentially accessible to personnel and in which...

Disentangling the major source areas for an intense aerosol advection in the Central Mediterranean on the basis of Potential Source Contribution Function modeling of chemical and size distribution measurements

NASA Astrophysics Data System (ADS)

Petroselli, Chiara; Crocchianti, Stefano; Moroni, Beatrice; Castellini, Silvia; Selvaggi, Roberta; Nava, Silvia; Calzolai, Giulia; Lucarelli, Franco; Cappelletti, David

2018-05-01

In this paper, we combined a Potential Source Contribution Function (PSCF) analysis of daily chemical aerosol composition data with hourly aerosol size distributions with the aim to disentangle the major source areas during a complex and fast modulating advection event impacting on Central Italy in 2013. Chemical data include an ample set of metals obtained by Proton Induced X-ray Emission (PIXE), main soluble ions from ionic chromatography and elemental and organic carbon (EC, OC) obtained by thermo-optical measurements. Size distributions have been recorded with an optical particle counter for eight calibrated size classes in the 0.27-10 μm range. We demonstrated the usefulness of the approach by the positive identification of two very different source areas impacting during the transport event. In particular, biomass burning from Eastern Europe and desert dust from Sahara sources have been discriminated based on both chemistry and size distribution time evolution. Hourly BT provided the best results in comparison to 6 h or 24 h based calculations.

Integrated, flexible, and rapid geophysical surveying

NASA Astrophysics Data System (ADS)

Miller, S. F.; McGinnis, L. D.; Thompson, M. D.; Tome, C.

Aberdeen Proving Ground (APG) is currently managing a comprehensive Installation Restoration Program involving more than 360 solid-waste managing units contained within 13 study areas. The Edgewood area and two landfills in the Aberdeen area appear on the National Priority List under the Comprehensive Environmental Response, Compensation, and Liability Act. Therefore, APG has entered into an interagency agreement with the US Environmental Protection Agency to address the listed areas. The West Branch of the Canal Creek area, located within the Edgewood area, is one of the areas that requires a Source Definition Study because there is an ongoing release of volatile organic compounds into the creek. A report prepared in 1989 included a list of 29 potentially contaminated buildings in the Edgewood area. Sixteen of the buildings contain known contaminants, nine buildings contain unknown contaminants, and four of the buildings are potentially clean. The EAI report recommended that a sampling and monitoring program be established to verify contamination levels in and around each building. Thirteen of the potentially contaminated buildings are in the West Branch of the Canal Creek area and are potential sources of volatile organic compounds. Operations have ceased, and the buildings have been abandoned, but processing equipment, sumps, drains, ventilation systems, and underground storage tanks remain. These appurtenances may contain liquid, solid, or vapor contaminants of unknown nature.

Mineralogy and source rock evaluation of the marine Oligo-Miocene sediments in some wells in the Nile Delta and North Sinai, Egypt

NASA Astrophysics Data System (ADS)

El sheikh, Hassan; Faris, Mahmoud; Shaker, Fatma; Kumral, Mustafa

2016-06-01

This paper aims to study the mineralogical composition and determine the petroleum potential of source rocks of the Oligocene-Miocene sequence in the Nile Delta and North Sinai districts. The studied interval in the five wells can be divided into five rock units arranged from the top to base; Qawasim, Sidi Salem, Kareem, Rudeis, and Qantara formations. The bulk rock mineralogy of the samples was investigated using X-Ray Diffraction technique (XRD). The results showed that the sediments of the Nile Delta area are characterized by the abundance of quartz and kaolinite with subordinate amounts of feldspars, calcite, gypsum, dolomite, and muscovite. On the other hand, the data of the bulk rock analysis at the North Sinai wells showed that kaolinite, quartz, feldspar and calcite are the main constituents associated with minor amounts of dolomite, gypsum, mica, zeolite, and ankerite. Based on the organic geochemical investigations (TOC and Rock-Eval pyrolysis analyses), all studied formations in both areas are thermally immature but in the Nile delta area, Qawasim, Sidi Salem and Qantara formations (El-Temsah-2 Well) are organically-rich and have a good petroleum potential (kerogen Type II-oil-prone), while Rudeis Formation is a poor petroleum potential source rock (kerogen Type III-gas-prone). In the North Sinai area, Qantara Formation has a poor petroleum potential (kerogen Type III-gas-prone) and Sidi Salem Formation (Bardawil-1 Well) is a good petroleum potential source rock (kerogen Type II-oil-prone).

TRAY MOUNTAIN ROADLESS AREA, GEORGIA.

USGS Publications Warehouse

Nelson, Arthur E.; Chatman, Mark L.

1984-01-01

A mineral survey indicates that the Tray Mountain Roadless Area, Georgia has little promise for the occurrence of metallic mineral resources. Rocks underlying the Tray Mountain Roadless Area are suitable for crushed rock or aggregate; however, other sources for these materials are available closer to present markets. There is a possibility for the occurrence of hydrocarbon resources underlying the area at great depth, but no hydrocarbon potential was identified. Detailed studies are needed to establish the presence or absence and mineral-resource potential of olivine, nickel, cobalt, and chrome in the two mafic-ultramafic bodies in the Hayesville thrust sheet. The cause of the lead anomaly in pan concentrate samples taken from the southwest part of the roadless area has not been established; the mineral residence and source of the anomaly remain to be determined.

Preliminary Assessment of Health Risks of Potentially Toxic Elements in Settled Dust over Beijing Urban Area

PubMed Central

Wan, Dejun; Zhan, Changlin; Yang, Guanglin; Liu, Xingqi; Yang, Jinsong

2016-01-01

To examine levels, health risks, sources, and spatial distributions of potentially toxic elements in settled dust over Beijing urban area, 62 samples were collected mostly from residential building outdoor surfaces, and their <63 μm fractions were measured for 12 potentially toxic elements. The results show that V, Cr, Mn, Co, Ni, and Ba in dust are from predominantly natural sources, whereas Cu, Zn, As, Cd, Sb, and Pb mostly originate from anthropogenic sources. Exposure to these elements in dust has significant non-cancer risks to children but insignificant to adults. Cancer risks of Cr, Co, Ni, As, and Cd via inhalation and dermal contact are below the threshold of 10−6–10−4 but As via dust ingestion shows a tolerable risk. The non-cancer risks to children are contributed mainly (75%) by As, Pb, and Sb, and dominantly (92%) via dust ingestion, with relatively higher risks mainly occurring in the eastern and northeastern Beijing urban areas. Although Cd, Zn, and Cu in dust are heavily affected by anthropogenic sources, their health risks are insignificant. Source appointments suggest that coal burning emissions, the dominant source of As, are likely the largest contributors to the health risk, and traffic-related and industrial emissions are also important because they contribute most of the Pb and Sb in dust. PMID:27187427

Scenarios for earthquake-generated tsunamis on a complex tectonic area of diffuse deformation and low velocity: The Alboran Sea, Western Mediterranean

USGS Publications Warehouse

Alvarez-Gomez, J. A.; Aniel-Quiroga, I.; Gonzalez, M.; Olabarrieta, Maitane; Carreno, E.

2011-01-01

The tsunami impact on the Spanish and North African coasts of the Alboran Sea generated by several reliable seismic tsunamigenic sources in this area was modeled. The tectonic setting is complex and a study of the potential sources from geological data is basic to obtain probable source characteristics. The tectonic structures considered in this study as potentially tsunamigenic are: the Alboran Ridge associated structures, the Carboneras Fault Zone and the Yusuf Fault Zone. We characterized 12 probable tsunamigenic seismic sources in the Alboran Basin based on the results of recent oceanographical studies. The strain rate in the area is low and therefore its seismicity is moderate and cannot be used to infer characteristics of the major seismic sources. These sources have been used as input for the numerical simulation of the wave propagation, based on the solution of the nonlinear shallow water equations through a finite-difference technique. We calculated the Maximum Wave Elevations, and Tsunami Travel Times using the numerical simulations. The results are shown as maps and profiles along the Spanish and African coasts. The sources associated with the Alboran Ridge show the maximum potential to generate damaging tsunamis, with maximum wave elevations in front of the coast exceeding 1.5 m. The Carboneras and Yusuf faults are not capable of generating disastrous tsunamis on their own, although their proximity to the coast could trigger landslides and associated sea disturbances. The areas which are more exposed to the impact of tsunamis generated in the Alboran Sea are the Spanish coast between Malaga and Adra, and the African coast between Alhoceima and Melilla.

Methods Used to Assess the Susceptibility to Contamination of Transient, Non-Community Public Ground-Water Supplies in Indiana

USGS Publications Warehouse

Arihood, Leslie D.; Cohen, David A.

2006-01-01

The Safe Water Drinking Act of 1974 as amended in 1996 gave each State the responsibility of developing a Source-Water Assessment Plan (SWAP) that is designed to protect public-water supplies from contamination. Each SWAP must include three elements: (1) a delineation of the source-water protection area, (2) an inventory of potential sources of contaminants within the area, and (3) a determination of the susceptibility of the public-water supply to contamination from the inventoried sources. The Indiana Department of Environmental Management (IDEM) was responsible for preparing a SWAP for all public-water supplies in Indiana, including about 2,400 small public ground-water supplies that are designated transient, non-community (TNC) supplies. In cooperation with IDEM, the U.S. Geological Survey compiled information on conditions near the TNC supplies and helped IDEM complete source-water assessments for each TNC supply. The delineation of a source-water protection area (called the assessment area) for each TNC ground-water supply was defined by IDEM as a circular area enclosed by a 300-foot radius centered at the TNC supply well. Contaminants of concern (COCs) were defined by IDEM as any of the 90 contaminants for which the U.S. Environmental Protection Agency has established primary drinking-water standards. Two of these, nitrate as nitrogen and total coliform bacteria, are Indiana State-regulated contaminants for TNC water supplies. IDEM representatives identified potential point and nonpoint sources of COCs within the assessment area, and computer database retrievals were used to identify potential point sources of COCs in the area outside the assessment area. Two types of methods-subjective and subjective hybrid-were used in the SWAP to determine susceptibility to contamination. Subjective methods involve decisions based upon professional judgment, prior experience, and (or) the application of a fundamental understanding of processes without the collection and analysis of data for a specific condition. Subjective hybrid methods combine subjective methods with quantitative hydrologic analyses. The subjective methods included an inventory of potential sources and associated contaminants, and a qualitative description of the inherent susceptibility of the area around the TNC supply. The description relies on a classification of the hydrogeologic and geomorphic characteristics of the general area around the TNC supply in terms of its surficial geology, regional aquifer system, the occurrence of fine- and coarse-grained geologic materials above the screen of the TNC well, and the potential for infiltration of contaminants. The subjective hybrid method combined the results of a logistic regression analysis with a subjective analysis of susceptibility and a subjective set of definitions that classify the thickness of fine-grained geologic materials above the screen of a TNC well in terms of impedance to vertical flow. The logistic regression determined the probability of elevated concentrations of nitrate as nitrogen (greater than or equal to 3 milligrams per liter) in ground water associated with specific thicknesses of fine-grained geologic materials above the screen of a TNC well. In this report, fine-grained geologic materials are referred to as a geologic barrier that generally impedes vertical flow through an aquifer. A geologic barrier was defined to be thin for fine-grained materials between 0 and 45 feet thick, moderate for materials between 45 and 75 feet thick, and thick if the fine-grained materials were greater than 75 feet thick. A flow chart was used to determine the susceptibility rating for each TNC supply. The flow chart indicated a susceptibility rating using (1) concentrations of nitrate as nitrogen and total coliform bacteria reported from routine compliance monitoring of the TNC supply, (2) the presence or absence of potential sources of regulated contaminants (nitrate as nitrogen and coliform bac

Oils and hydrocarbon source rocks of the Baltic syneclise

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kanev, S.; Margulis, L.; Bojesen-Koefoed, J.A.

Prolific source rock horizons of varying thickness, having considerable areal extent, occur over the Baltic syneclise. These source sediments are rich and have excellent petroleum generation potential. Their state of thermal maturity varies form immature in the northeastern part of the syneclise to peak generation maturity in the southwestern part of the region-the main kitchen area. These maturity variations are manifest in petroleum composition in the region. Hence, mature oils occur in the Polish and Kaliningrad areas, immature oils in small accumulations in Latvian and central Lithuanian onshore areas, and intermediate oils in areas between these extremes. The oil accumulationsmore » probably result from pooling of petroleum generated from a number of different source rocks at varying levels of thermal maturity. Hence, no single source for petroleum occurrences in the Baltic syneclise may be identified. The paper describes the baltic syneclise, source rocks, thermal maturity and oils and extracts.« less

The Bolivian source rocks: Sub Andean Zone-Madre de Dios-Chaco

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moretti, I.; Montemurro, G.; Aguilera, E.

A complete study of source rocks has been carried out in the Bolivian foothills and foreland (Sub Andean Zone, Chaco and Madre de Dios) in order to quantify the petroleum potential of the area. Besides the classical mid-Devonian source rocks (Tequeje Formation in the north, Limoncito Formation in the center and Los Monos Formation in the south), others are important: the Tomachi Formation (late Devonian) in the north and the Copacabana Formation (Upper Carboniferous-lower Permian) in the northern Sub Andean Zone. Both show an excellent potential with S{sub 2} over 50 mg HC/g and average values higher than 10 mgmore » HC/g over few hundred meters. The Latest Cretaceous Flora Formation present locally a high potential but is very thin. Almost all the source rocks matured during the Neogene due to the subsidence in the Andean foreland and in the piggyback basins, and are thus involved on the current petroleum system. Silurian and Lower Paleozoic units also contain thick shale beds, but these source rocks were mature before the Jurassic in the south of the country. In the center, the Silurian is not nowadays overmature and may play an important role. The different zones are compared based on their Source Potential Index which indicates that the richest areas are the northern Sub Andean Zone and the Madre de Dios basin with SPI greater than 10 t/m{sup 2}. Since these two areas remain almost unexplored, these results allow us to be optimistic about the possibilities for future exploration.« less

Identification of potential rockfall source areas at a regional scale using a DEM-based geomorphometric analysis

NASA Astrophysics Data System (ADS)

Loye, A.; Jaboyedoff, M.; Pedrazzini, A.

2009-10-01

The availability of high resolution Digital Elevation Models (DEM) at a regional scale enables the analysis of topography with high levels of detail. Hence, a DEM-based geomorphometric approach becomes more accurate for detecting potential rockfall sources. Potential rockfall source areas are identified according to the slope angle distribution deduced from high resolution DEM crossed with other information extracted from geological and topographic maps in GIS format. The slope angle distribution can be decomposed in several Gaussian distributions that can be considered as characteristic of morphological units: rock cliffs, steep slopes, footslopes and plains. A terrain is considered as potential rockfall sources when their slope angles lie over an angle threshold, which is defined where the Gaussian distribution of the morphological unit "Rock cliffs" become dominant over the one of "Steep slopes". In addition to this analysis, the cliff outcrops indicated by the topographic maps were added. They contain however "flat areas", so that only the slope angles values above the mode of the Gaussian distribution of the morphological unit "Steep slopes" were considered. An application of this method is presented over the entire Canton of Vaud (3200 km2), Switzerland. The results were compared with rockfall sources observed on the field and orthophotos analysis in order to validate the method. Finally, the influence of the cell size of the DEM is inspected by applying the methodology over six different DEM resolutions.

A Global Sensitivity Analysis Method on Maximum Tsunami Wave Heights to Potential Seismic Source Parameters

NASA Astrophysics Data System (ADS)

Ren, Luchuan

2015-04-01

A Global Sensitivity Analysis Method on Maximum Tsunami Wave Heights to Potential Seismic Source Parameters Luchuan Ren, Jianwei Tian, Mingli Hong Institute of Disaster Prevention, Sanhe, Heibei Province, 065201, P.R. China It is obvious that the uncertainties of the maximum tsunami wave heights in offshore area are partly from uncertainties of the potential seismic tsunami source parameters. A global sensitivity analysis method on the maximum tsunami wave heights to the potential seismic source parameters is put forward in this paper. The tsunami wave heights are calculated by COMCOT ( the Cornell Multi-grid Coupled Tsunami Model), on the assumption that an earthquake with magnitude MW8.0 occurred at the northern fault segment along the Manila Trench and triggered a tsunami in the South China Sea. We select the simulated results of maximum tsunami wave heights at specific sites in offshore area to verify the validity of the method proposed in this paper. For ranking importance order of the uncertainties of potential seismic source parameters (the earthquake's magnitude, the focal depth, the strike angle, dip angle and slip angle etc..) in generating uncertainties of the maximum tsunami wave heights, we chose Morris method to analyze the sensitivity of the maximum tsunami wave heights to the aforementioned parameters, and give several qualitative descriptions of nonlinear or linear effects of them on the maximum tsunami wave heights. We quantitatively analyze the sensitivity of the maximum tsunami wave heights to these parameters and the interaction effects among these parameters on the maximum tsunami wave heights by means of the extended FAST method afterward. The results shows that the maximum tsunami wave heights are very sensitive to the earthquake magnitude, followed successively by the epicenter location, the strike angle and dip angle, the interactions effect between the sensitive parameters are very obvious at specific site in offshore area, and there exist differences in importance order in generating uncertainties of the maximum tsunami wave heights for same group parameters at different specific sites in offshore area. These results are helpful to deeply understand the relationship between the tsunami wave heights and the seismic tsunami source parameters. Keywords: Global sensitivity analysis; Tsunami wave height; Potential seismic tsunami source parameter; Morris method; Extended FAST method

Methods for evaluating potential sources of chloride in surface waters and groundwaters of the conterminous United States

USGS Publications Warehouse

Granato, Gregory E.; DeSimone, Leslie A.; Barbaro, Jeffrey R.; Jeznach, Lillian C.

2015-09-04

Scientists, engineers, regulators, and decisionmakers need information about potential sources of chloride, water and solute budgets, and methods for collecting water-quality data to help identify potential sources. This information is needed to evaluate potential sources of chloride in areas where chloride may have adverse ecological effects or may degrade water supplies used for drinking water, agriculture, or industry. Knowledge of potential sources will help decisionmakers identify the best mitigation measures to reduce the total background chloride load, thereby reducing the potential for water-quality exceedances that occur because of superposition on rising background concentrations. Also, knowledge of potential sources may help decisionmakers identify the potential for the presence of contaminants that have toxic, carcinogenic, mutagenic, or endocrine-disrupting effects at concentrations that are lower by orders of magnitude than the chloride concentrations in the source water. This report is a comprehensive synthesis of relevant information, but it is not the result of an exhaustive search for literature on each topic. The potential adverse effects of chloride on infrastructure and the environment are not discussed in this report because these issues have been extensively documented elsewhere.

Integrated, flexible, and rapid geophysical surveying

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, S.F.; McGinnis, L.D.; Thompson, M.D.

1993-01-01

Aberdeen Proving Ground (APG), in the state of Maryland (Figure 1), is currently managing a comprehensive Installation Restoration Program involving more than 360 solid-waste managing units contained within 13 study areas. The Edgewood area and two landfills in the Aberdeen area appear on the National Priority List under the Comprehensive Environmental Response, Compensation, and Liability Act. Therefore, APG has entered into an interagency agreement with the US Environmental Protection Agency to address the listed areas. The West Branch of the Canal Creek area (Figure 1), located within the Edgewood area, is one of the areas that requires a Source Definitionmore » Study because there is an ongoing release of volatile organic compounds into the creek. A report prepared by EAI Corporation (1989) included a list of 29 potentially contaminated buildings in the Edgewood area. Sixteen of the buildings contain known contaminants, nine buildings contain unknown contaminants, and four of the buildings are potentially clean. The EAI report recommended that a sampling and monitoring program be established to verify contamination levels in and around each building. Thirteen of the potentially contaminated buildings are in the West Branch of the Canal Creek area and are potential sources of volatile organic compounds. Operations have ceased and the buildings have been abandoned, but processing equipment, sumps, drains, ventilation systems, and underground storage tanks remain. These appurtenances may contain liquid, solid, or vapor contaminants of unknown nature.« less

Integrated, flexible, and rapid geophysical surveying

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, S.F.; McGinnis, L.D.; Thompson, M.D.

1993-03-01

Aberdeen Proving Ground (APG), in the state of Maryland (Figure 1), is currently managing a comprehensive Installation Restoration Program involving more than 360 solid-waste managing units contained within 13 study areas. The Edgewood area and two landfills in the Aberdeen area appear on the National Priority List under the Comprehensive Environmental Response, Compensation, and Liability Act. Therefore, APG has entered into an interagency agreement with the US Environmental Protection Agency to address the listed areas. The West Branch of the Canal Creek area (Figure 1), located within the Edgewood area, is one of the areas that requires a Source Definitionmore » Study because there is an ongoing release of volatile organic compounds into the creek. A report prepared by EAI Corporation (1989) included a list of 29 potentially contaminated buildings in the Edgewood area. Sixteen of the buildings contain known contaminants, nine buildings contain unknown contaminants, and four of the buildings are potentially clean. The EAI report recommended that a sampling and monitoring program be established to verify contamination levels in and around each building. Thirteen of the potentially contaminated buildings are in the West Branch of the Canal Creek area and are potential sources of volatile organic compounds. Operations have ceased and the buildings have been abandoned, but processing equipment, sumps, drains, ventilation systems, and underground storage tanks remain. These appurtenances may contain liquid, solid, or vapor contaminants of unknown nature.« less

CHATTAHOOCHEE ROADLESS AREA, GEORGIA.

USGS Publications Warehouse

Nelson, Arthur E.; Welsh, Robert A.

1984-01-01

A mineral survey indicates that the Chattahoochee Roadless Area, Georgia, offers little promise for the occurrence of mineral resources even though gold, mica, sillimanite, soapstone, dunite, chromite, and nickel have been mined nearby, and source rocks for these commodities are present in the roadless area. Granite gneiss, gneiss, schist, and metasandstone in the roadless area are suitable for stone, crushed rock, or aggregate; however, other sources for these materials are available outside the roadless area, closer to present markets. The potential for the occurrence of hydrocarbons (probably gas) beneath the thick regional thrust sheets in this area cannot be adequately evaluated from available data.

Comparison of hybrid receptor models to locate PCB sources in Chicago

NASA Astrophysics Data System (ADS)

Hsu, Ying-Kuang; Holsen, Thomas M.; Hopke, Philip K.

Results of three hybrid receptor models, potential source contribution function (PSCF), concentration weighted trajectory (CWT), and residence time weighted concentration (RTWC), were compared for locating polychlorinated biphenyl (PCB) sources contributing to the atmospheric concentrations in Chicago. Variations of these models, including PSCF using mean and 75% criterion concentrations, joint probability PSCF (JP-PSCF), changes of point filters and grid cell sizes for RTWC, and PSCF using wind trajectories started at different altitudes, are also discussed. Modeling results were relatively consistent between models. However, no single model provided as complete information as was obtained by using all of them. CWT and 75% PSCF appears to be able to distinguish between larger sources and moderate ones. RTWC resolved high potential source areas. RTWC and JP-PSCF pooling data from all sampling sites removed the trailing effect often seen in PSCF modeling. PSCF results using average concentration criteria, appears to identify both moderate and major sources. Each model has advantages and disadvantages. However, used in combination, they provide information that is not available if only one of them is used. For short-range atmospheric transport, PSCF results were consistent when using wind trajectories starting at different heights. Based on the archived PCB data, the modeling results indicate there is a large potential source area between Joliet and Kankakee, IL, and two moderate sources to the northwest and south of Chicago. On the south side of Chicago in the neighborhood of Lake Calumet, several PCB sources were identified. Other unidentified potential source location(s) will require additional upwind/downwind field sampling to verify modeling results.

Subsurface occurrence and potential source areas of chlorinated ethenes identified using concentrations and concentration ratios, Air Force Plant 4 and Naval Air Station-Joint Reserve Base Carswell Field, Fort Worth, Texas

USGS Publications Warehouse

Garcia, C. Amanda

2005-01-01

The U.S. Geological Survey, in cooperation with the U.S. Air Force Aeronautical Systems Center, Environmental Management Directorate, conducted a study during 2003-05 to characterize the subsurface occurrence and identify potential source areas of the volatile organic compounds classified as chlorinated ethenes at U.S. Air Force Plant 4 (AFP4) and adjacent Naval Air Station-Joint Reserve Base Carswell Field (NAS-JRB) at Fort Worth, Texas. The solubilized chlorinated ethenes detected in the alluvial aquifer originated as either released solvents (tetrachloroethene [PCE], trichloroethene [TCE], and trans-1,2-dichloroethene [trans-DCE]) or degradation products of the released solvents (TCE, cis-1,2-dichloroethene [cis-DCE], and trans-DCE). The combined influences of topographic- and bedrock-surface configurations result in a water table that generally slopes away from a ground-water divide approximately coincident with bedrock highs and the 1-mile-long aircraft assembly building at AFP4. Highest TCE concentrations (10,000 to 920,000 micrograms per liter) occur near Building 181, west of Building 12, and at landfill 3. Highest PCE concentrations (500 to 920 micrograms per liter) occur near Buildings 4 and 5. Highest cis-DCE concentrations (5,000 to 710,000 micrograms per liter) occur at landfill 3. Highest trans-DCE concentrations (1,000 to 1,700 micrograms per liter) occur just south of Building 181 and at landfill 3. Ratios of parent-compound to daughter-product concentrations that increase in relatively short distances (tens to 100s of feet) along downgradient ground-water flow paths can indicate a contributing source in the vicinity of the increase. Largest increases in ratio of PCE to TCE concentrations are three orders of magnitude from 0.01 to 2.7 and 7.1 between nearby wells in the northeastern part of NAS-JRB. In the northern part of NAS-JRB, the largest increases in TCE to total DCE concentration ratios relative to ratios at upgradient wells are from 17 to 240 or from 17 to 260. In the southern part of NAS-JRB, the largest ratio increases with respect to those at upgradient wells are from 22 and 24 to 130, and from 0 and 7.2 to 71. Numerous maximum historical ratios of trans-DCE to cis-DCE are greater than 1, which can indicate that trans-DCE likely was released as a solvent and does not occur only as a result of degradation of TCE. High concentrations of TCE, PCE, cis-DCE, and trans-DCE, abrupt increases in ratios of PCE to TCE and TCE to total DCE, and ratios of trans-DCE to cis-DCE greater than 1 were used to identify 16 potential source areas of chlorinated ethenes at NAS-JRB. The evidence for some of the potential source areas is stronger than for others, but each area reflects one or more of the conditions indicative of chlorinated ethenes entering the aquifer. Potential source areas supported by the strongest evidence are Building 181, between buildings 4 and 5, just west of Building 12, and landfills 1 and 3. The highest historical TCE concentration in the study area, 920,000 micrograms per liter, is near Building 181. The potential source area between Buildings 4 and 5 primarily is identified by notably high PCE concentrations (to 920 micrograms per liter). Primary evidence for the potential source are just west of Building 12 is the notably high TCE concentrations (for example, 160,000 micrograms per liter) that appear to originate in the area. Primary evidence for the potential source area at landfills 1 and (primarily) 3 is the magnitudes of TCE concentrations (for example, two in the 100,000-to-920,000-microgram-per-liter range), cis-DCE concentrations (several in the 5,000-to-710,000-microgram-per-liter range), and trans-DCE concentrations (several in the 500-to-1,700-microgram-per-liter range). The ratio of trans-DCE to cis-DCE at one well in landfill 3 (6.7) is appreciably above the threshold that can indicate likely solvent release as opposed to TCE degradation alone.

Soil and building material as main sources of indoor radon in Băiţa-Ştei radon prone area (Romania).

PubMed

Cosma, Constantin; Cucoş-Dinu, Alexandra; Papp, Botond; Begy, Robert; Sainz, Carlos

2013-02-01

Radon contributes to over than 50% of the natural radiation dose received by people. In radon risk areas this contribution can be as high as 90-95%, leading to an exposure to natural radiation 5-10 times higher than normal. This work presents results from radon measurements (indoor, soil and exhalation from building materials) in Băiţa-Ştei, a former uranium exploitation area in NW Romania. In this region, indoor radon concentrations found were as high as 5000 Bq m(-3) and soil radon levels ranged from 20 to 500 kBq m(-3). An important contribution from building materials to indoor radon was also observed. Our results indicate two independent sources of indoor radon in the surveyed houses of this region. One source is coming from the soil and regular building materials, and the second source being uranium waste and local radium reached material used in building construction. The soil as source of indoor radon shows high radon potential in 80% of the investigated area. Some local building materials reveal high radon exhalation rate (up to 80 mBq kg(-1) h(-1) from a sandy-gravel material, ten times higher than normal material). These measurements were used for the radon risk classification of this area by combining the radon potential of the soil with the additional component from building materials. Our results indicate that Băiţa-Ştei area can be categorized as a radon prone area. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

Distributed watershed modeling of design storms to identify nonpoint source loading areas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Endreny, T.A.; Wood, E.F.

1999-03-01

Watershed areas that generate nonpoint source (NPS) polluted runoff need to be identified prior to the design of basin-wide water quality projects. Current watershed-scale NPS models lack a variable source area (VSA) hydrology routine, and are therefore unable to identify spatially dynamic runoff zones. The TOPLATS model used a watertable-driven VSA hydrology routine to identify runoff zones in a 17.5 km{sup 2} agricultural watershed in central Oklahoma. Runoff areas were identified in a static modeling framework as a function of prestorm watertable depth and also in a dynamic modeling framework by simulating basin response to 2, 10, and 25 yrmore » return period 6 h design storms. Variable source area expansion occurred throughout the duration of each 6 h storm and total runoff area increased with design storm intensity. Basin-average runoff rates of 1 mm h{sup {minus}1} provided little insight into runoff extremes while the spatially distributed analysis identified saturation excess zones with runoff rates equaling effective precipitation. The intersection of agricultural landcover areas with these saturation excess runoff zones targeted the priority potential NPS runoff zones that should be validated with field visits. These intersected areas, labeled as potential NPS runoff zones, were mapped within the watershed to demonstrate spatial analysis options available in TOPLATS for managing complex distributions of watershed runoff. TOPLATS concepts in spatial saturation excess runoff modelling should be incorporated into NPS management models.« less

Oil spill contamination probability in the southeastern Levantine basin.

PubMed

Goldman, Ron; Biton, Eli; Brokovich, Eran; Kark, Salit; Levin, Noam

2015-02-15

Recent gas discoveries in the eastern Mediterranean Sea led to multiple operations with substantial economic interest, and with them there is a risk of oil spills and their potential environmental impacts. To examine the potential spatial distribution of this threat, we created seasonal maps of the probability of oil spill pollution reaching an area in the Israeli coastal and exclusive economic zones, given knowledge of its initial sources. We performed simulations of virtual oil spills using realistic atmospheric and oceanic conditions. The resulting maps show dominance of the alongshore northerly current, which causes the high probability areas to be stretched parallel to the coast, increasing contamination probability downstream of source points. The seasonal westerly wind forcing determines how wide the high probability areas are, and may also restrict these to a small coastal region near source points. Seasonal variability in probability distribution, oil state, and pollution time is also discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Milan Army Ammunition Plant remedial investigation report: Volume 1. Final report 89-91

DOE Office of Scientific and Technical Information (OSTI.GOV)

Okusu, N.; Hall, H.; Orndorff, A.

1991-12-09

A Remedial Investigation at the Milan Army Ammunition Plant, TN, was conducted for the US Army Toxic and Hazardous Materials Agency, under the terms of an Interagency Agreement with the State of Tennessee and the US Environmental Protection Agency. The study focused on the CERCLA site and selected RCRA regulated units identified by previous studies as potential sources of contamination. A broad range of chemicals including metals, explosives, and other organic compounds were found in source areas and in groundwater. The results of a risk assessment indicate that unacceptable levels of human health risks potentially exist. Conceptual models of sitemore » and unit characteristics were formulated to explain major findings, and areas not contributing to the problem were identified. For many source areas, major unknowns exist regarding hydrology, extent of contamination, and current and future impacts to groundwater quality.« less

Water resources of part of Canyonlands National Park, southeastern Utah

USGS Publications Warehouse

Sumsion, C.T.; Bloke, E.L.

1972-01-01

Canyonlands National Park is in about the center of the Canyon Lands section of the Colorado Plateaus physiographic province in southeastern Utah. The part of the park discussed embraces an area of about 400 square miles comprising isolated mesas, precipitous canyons, and dissected broad benches near the confluence of the Green and Colorado Rivers, the only perennial streams in the area. The climate is arid to semiarid; normal annual precipitation ranges from less than 8 to about 10 inches. Potential evapotranspiration is about 41 inches annually.Geology of the park is characterized by nearly horizontal strata that dip gently northward. Exposed rock formations and deposits range in age from Middle Pennsylvanian to Holocene. Owing to the elevated and deeply dissected topography, only parts of the Cedar Mesa and White Rim Sandstone Members of the Cutler Formation of Permian age have potential for development of wells. Strata above and below them support only small springs, are dry, or contain brine.In the northwest part of the park, the Green River at Taylor Canyon is a potential source of surface water for public supplies for the Island In The Sky area and a small part of the northwest White Rim area. It will require filtration and treatment before use. In the same area, two unused wells in Taylor Canyon will supply enough water for present requirements from the White Rim Sandstone Member of the Cutler Formation, about 140 gallons per minute combined, but yield mineralized water that will require treatment before use. Springs yielding good water at the Island In The Sky and White Rim are mostly intermittent and too small for public-water supply. Most of the White Rim area is dry, having no usable ground water. In The Needles area, wells provide water of good quality from the Cedar Mesa Sandstone Member of the Cutler Formation. Springs yielding good water in the same area are available for supplementary supplies. West of The Needles, The Grabens area is without springs or potential aquifers bearing usable water.During 1970 about 510,000 gallons of water was used in Canyonlands National Park. Of this amount, 110,000 gallons was supplied to Island In The Sky by tank truck from a source outside the park, and about 400,000 gallons was withdrawn from the well in use at The Needles. Estimated total annual requirements in 10 years (1980) may be as much as 6 million gallons. Sources of water supplies within the park now in use and potential sources of surface water or ground water outlined by this investigation will meet the estimated requirements. Development of rainfall-collection and cistern-storage systems could furnish small emergency sources of water for waterless areas on the White Rim and in The Grabens.

Distinguishing dark matter from unresolved point sources in the Inner Galaxy with photon statistics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Samuel K.; Lisanti, Mariangela; Safdi, Benjamin R., E-mail: samuelkl@princeton.edu, E-mail: mlisanti@princeton.edu, E-mail: bsafdi@princeton.edu

2015-05-01

Data from the Fermi Large Area Telescope suggests that there is an extended excess of GeV gamma-ray photons in the Inner Galaxy. Identifying potential astrophysical sources that contribute to this excess is an important step in verifying whether the signal originates from annihilating dark matter. In this paper, we focus on the potential contribution of unresolved point sources, such as millisecond pulsars (MSPs). We propose that the statistics of the photons—in particular, the flux probability density function (PDF) of the photon counts below the point-source detection threshold—can potentially distinguish between the dark-matter and point-source interpretations. We calculate the flux PDFmore » via the method of generating functions for these two models of the excess. Working in the framework of Bayesian model comparison, we then demonstrate that the flux PDF can potentially provide evidence for an unresolved MSP-like point-source population.« less

Online Characterisation of Mineral Dust Aerosol by Single Particle Mass Spectrometry: Mineralogical Signatures of Potential Source Areas in North Africa.

NASA Astrophysics Data System (ADS)

Marsden, N. A.; Allan, J. D.; Flynn, M.; Ullrich, R.; Moehler, O.; Coe, H.

2017-12-01

The mineralogy of individual dust particles is important for atmospheric processes because mineralogy influences optical properties, their potential to act as ice nucleating particles (INP) and geochemical cycling of elements to the ocean. Bulk mineralogy of transported mineral dust has been shown to be a reflection of the source area and size fractionation during transport. Online characterisation of single particle mineralogy is highly desirable as the composition of individual particles can be reported at a temporal resolution that is relevant to atmospheric processes. Single particle mass spectrometry (SPMS) has indentified and characterised the composition of ambient dust particles but is hampered by matrix effects that result in a non-quantatative measurement of composition. The work presented describes a comparison of mass spectral characteristics of sub 2.5μm particle fractions generated from; i) nominally pure samples from the clay mineral society (CMS), ii) soil samples collected from potential source areas in North Africa and iii) ambient measurement of transported African dust made at the Cape Verde Islands. Using a novel approach to analyse the mass spectra, the distinct characteristics of the various dust samples are obtained from the online measurements. Using this technique it was observed that dust generated from sources on the North West Margin of the Sahara Desert have distinct characteristics of illite in contrast to the kaolinitic characteristics of dust generated from sources in the Sahel. These methods offer great potential for describing the hourly variation in the source and mineralogy of transported mineral dust and the online differentiation of mineral phase in multi-mineralic dust samples.

Aliphatic and polycyclic aromatic hydrocarbons in Gulf of Trieste sediments (northern Adriatic): potential impacts of maritime traffic.

PubMed

Bajt, Oliver

2014-09-01

The Gulf of Trieste (northern Adriatic) is one of the most urbanized and industrialized areas in the northern Adriatic, with intense maritime traffic experienced at multiple ports. The impact of maritime traffic on contamination by hydrocarbons in this area was assessed. Concentrations of hydrocarbons were higher near the expected contamination sources and still elevated in the adjacent offshore areas. Aliphatic hydrocarbons were mainly of petrogenic origin, with some contribution of biogenic origin. A continuous contamination by aliphatic hydrocarbons and degradation processes were hypothesized. Concentrations of total polycyclic aromatic hydrocarbons (PAH) were generally greater near the contamination sources. Compared to the prevailing pyrolytic origin, the petrogenic PAH origin seemed to be less important, but not negligible. Results revealed that intensive maritime traffic is a probable source of contamination by hydrocarbons in the investigated area, which is largely limited to areas near the contamination sources.

Possible emissions of POPs in plain and hilly areas of Nepal: Implications for source apportionment and health risk assessment.

PubMed

Yadav, Ishwar Chandra; Devi, Ningombam Linthoingambi; Li, Jun; Zhang, Gan; Breivik, Knut

2017-01-01

Ambient air is a core media chosen for monitoring under the Stockholm Convention on POPs. While extensive monitoring of POPs in ambient air has been carried out in some parts of the globe, there are still regions with very limited information available, such as some developing countries as Nepal. This study therefore aims to target the occurrence of selected POPs in Nepal in suspected source areas/more densely populated regions. Four potential source regions in Nepal were furthermore targeted as it was hypothesized that urban areas at lower altitudes (Birgunj and Biratnagar located at approximately 86 and 80 m.a.s.l.) would be potentially more affected by OCPs because of more intensive agricultural activities in comparison to urban areas at higher altitudes (Kathmandu, Pokhara located 1400 and 1135 m.a.s.l). As some of these areas could also be impacted by LRAT, air mass back trajectories during the sampling period were additionally evaluated using HYSPLIT. The concentrations of overall POPs were twice as high in plain areas in comparison to hilly areas. DDTs and HCHs were most frequently detected in the air samples. The high p,p'-DDT/(pp'-DDE + pp'-DDD) ratio as well as the low o,p'-DDT/p,p'-DDT ratio observed in this study was inferred as continuing use of technical DDT. High levels of ∑ 26 PCBs were linked to proximity to highly urbanized and industrial areas, indicating the potential source of PCBs. The measured concentrations of legacy POPs in air from this study is assumed to represent a negligible health risk through inhalation of ambient air, however, other modes of human exposure could still be relevant in Nepal. The air mass backward trajectory analysis revealed that most of the air masses sampled originated from India and the Bay of Bengal. Copyright © 2016 Elsevier Ltd. All rights reserved.

Panama Canal Expansion Illustrates Need for Multimodal Near-Source Air Quality Assessment

EPA Science Inventory

The compelling issue raised is potential major changes in goods movement due to the Panama Canal expansion and considerations for near-source air quality. Near-source air quality may be affected both at near-port areas as well as along the freight transportation corridor.

Stable isotopes of lead and strontium as tracers of sources of airborne particulate matter in Kyrgyzstan.

EPA Science Inventory

Central Asia is dominated by an arid climate and desert-like conditions, leading to the potential of long-range transport of desert dust. One potential source of dust to Central Asia is the Aral Sea, the surface area of which has receded in size from 68,000 km2 to 14,280 km2, lar...

Agricultural areas in potentially contaminated sites: characterization, risk, management.

PubMed

Vanni, Fabiana; Scaini, Federica; Beccaloni, Eleonora

2016-01-01

In Italy, the current legislation for contaminants in soils provides two land uses: residential/public or private gardens and commercial/industrial; there are not specific reference values for agricultural soils, even if a special decree has been developed and is currently going through the legislative approval process. The topic of agricultural areas is relevant, also in consideration of their presence near potentially contaminated sites. Aim and results. In this paper, contamination sources and transport modes of contaminants from sources to the target in agricultural areas are examined and a suitable "conceptual model" to define appropriate characterization methods and risk assessment procedures is proposed. These procedures have already been used by the National Institute of Health in various Italian areas characterized by different agricultural settings. Finally, specific remediation techniques are suggested to preserve soil resources and, if possible, its particular land use.

Report list Arizona's oil, gas potential

USGS Publications Warehouse

Rauzi, S.L.

2001-01-01

This article is a summary of Arizona geological survey circular 29, which addresses the petroleum geology of Arizona, USA. Eight areas have been identified with fair to excellent oil and gas potential, and some Tertiary basins have evidence of source or reservoir rocks. The following are considered here: production history, lands status and services, regulation and permitting, petroleum geology, hydrocarbon indications, and areas with hydrocarbon potential and their petroleum geology and characteristics. The full report contains detailed figures of each of these basin areas, a descriptive tabulation of seeps and petroliferous rocks and extensive references.

Beach litter occurrence in sandy littorals: The potential role of urban areas, rivers and beach users in central Italy

NASA Astrophysics Data System (ADS)

Poeta, Gianluca; Conti, Luisa; Malavasi, Marco; Battisti, Corrado; Acosta, Alicia Teresa Rosario

2016-11-01

Litter washed ashore on the coastline, also called beach litter, constitutes one of the most obvious signs of marine litter pollution. Surveys of beach litter represent a fundamental tool for monitoring pollution in the marine environment and have been used world-wide to classify and quantify marine litter. Identifying the sources of marine and beach litter is, together with education, the prime weapon in combating this type of pollution. This work investigates the impact of three main potential land sources on litter occurrence: urban areas, rivers and beach users. Three sources were analyzed simultaneously on a broad scale (Lazio region, central Italy) using a random sampling design and fitting a generalized linear mixed-effect model. The results show that urban areas are the main drivers for the occurrence of marine litter along central Italy's coastal ecosystems, suggesting that the presence of such litter on Lazio beaches could be effectively reduced by identifying failings in recycling and waste collection procedures and by improving waste processing systems and sewage treatment in urban areas.

Petrographic Analyses of Lonestones from ODP Drill Sites Leg 188 Prydz Bay, Antarctica

NASA Astrophysics Data System (ADS)

Detterman, K.; Warnke, D. A.; Richter, C.

2006-12-01

ODP Leg 188 was drilled in 2000 to sample the first advances of the Antarctic ice sheet and to document further cryospheric development. Continental shelf Site 1166 documented the earliest stages of glaciation during the Eocene-Oligocene and continental slope Site 1167 documented rapid deposition by debris flows during the Pliocene-Pleistocene and a subtle change in onshore erosion areas. Site 1165, located on the continental rise, documented long-term transition from wet-based lower Miocene glaciers to dry-based upper Miocene glaciers, including short-term fluctuations starting in the early Miocene. Source areas for all drill sites are the Lambert Glacier-Amery Ice Shelf drainage area, encompassing the Northern and Southern Prince Charles Mountains, the Gamburtsev Sub-glacial Mountains, and the Grove Mountains. Lonestones occur in most of the cores from all sites of Leg 188 prompting research for potential source areas and transportation modes of the lonestones. One-hundred and seventeen thin sections of lonestones were prepared from Sites 1166, 1167, and 1165 for petrographic analyses. Metamorphic lonestones outnumber igneous and sedimentary lonestones at all three sites. Sedimentary lonestones were not found in the thin sections of Site 1166. Extrusive igneous lonestones were found only at Site 1165 and comprised 5.1 percent of Leg 188's lithology. The anorthite content of igneous and metamorphic lonestones represented at all three sites was albite-oligoclase plagioclase. Albite oligoclase plagioclase has been documented in the Southern Prince Charles Mountains. The results of this study of a selection of lonestones from Site 1167 supports a hypothesis first proposed by the Shipboard Scientific Party in 2001 that as time elapsed, the source area for Site 1167 lonestones shifted slightly from a largely sandstone source to a largely granitic source within the drainage area. One potential source area for the Site 1167 sandstone lonestones is the Permian to Triassic Amery Group in the Beaver Lake area of the Northern Prince Charles Mountains. We hypothesize that more easily eroded portions of the sandstone outcrops were planed off first while ubiquitous gneiss and granite outcrops provided the source material for the younger debris flows at Site 1167 in the Pliocene-Pleistocene. None of all the available lonestones suggest sources other than the drainage area of the Lambert Glacier- Amery Ice Shelf complex.

An integrated approach to assess heavy metal source apportionment in peri-urban agricultural soils.

PubMed

Huang, Ying; Li, Tingqiang; Wu, Chengxian; He, Zhenli; Japenga, Jan; Deng, Meihua; Yang, Xiaoe

2015-12-15

Three techniques (Isotope Ratio Analysis, GIS mapping, and Multivariate Statistical Analysis) were integrated to assess heavy metal pollution and source apportionment in peri-urban agricultural soils. The soils in the study area were moderately polluted with cadmium (Cd) and mercury (Hg), lightly polluted with lead (Pb), and chromium (Cr). GIS Mapping suggested Cd pollution originates from point sources, whereas Hg, Pb, Cr could be traced back to both point and non-point sources. Principal component analysis (PCA) indicated aluminum (Al), manganese (Mn), nickel (Ni) were mainly inherited from natural sources, while Hg, Pb, and Cd were associated with two different kinds of anthropogenic sources. Cluster analysis (CA) further identified fertilizers, waste water, industrial solid wastes, road dust, and atmospheric deposition as potential sources. Based on isotope ratio analysis (IRA) organic fertilizers and road dusts accounted for 74-100% and 0-24% of the total Hg input, while road dusts and solid wastes contributed for 0-80% and 19-100% of the Pb input. This study provides a reliable approach for heavy metal source apportionment in this particular peri-urban area, with a clear potential for future application in other regions. Copyright © 2015 Elsevier B.V. All rights reserved.

Identification of dust storm source areas in West Asia using multiple environmental datasets.

PubMed

Cao, Hui; Amiraslani, Farshad; Liu, Jian; Zhou, Na

2015-01-01

Sand and Dust storms are common phenomena in arid and semi-arid areas. West Asia Region, especially Tigris-Euphrates alluvial plain, has been recognized as one of the most important dust source areas in the world. In this paper, a method is applied to extract SDS (Sand and Dust Storms) sources in West Asia region using thematic maps, climate and geography, HYSPLIT model and satellite images. Out of 50 dust storms happened during 2000-2013 and collected in form of MODIS images, 27 events were incorporated as demonstrations of the simulated trajectories by HYSPLIT model. Besides, a dataset of the newly released Landsat images was used as base-map for the interpretation of SDS source regions. As a result, six main clusters were recognized as dust source areas. Of which, 3 clusters situated in Tigris-Euphrates plain were identified as severe SDS sources (including 70% dust storms in this research). Another cluster in Sistan plain is also a potential source area. This approach also confirmed six main paths causing dust storms. These paths are driven by the climate system including Siberian and Polar anticyclones, monsoon from Indian Subcontinent and depression from north of Africa. The identification of SDS source areas and paths will improve our understandings on the mechanisms and impacts of dust storms on socio-economy and environment of the region. Copyright © 2014 Elsevier B.V. All rights reserved.

Hydrocarbon prospectivity assessment of the Southern Pattani Trough, Gulf of Thailand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mountford, N.

The Pattani Trough is an elongate north to south basin in the Gulf of Thailand offshore area that developed from Oligocene times onward. Numerous hydrocarbon discoveries, mainly gas, have been made within the Tertiary stratigraphic section in areas adjacent to the depocenter of the basin, but only dry holes have been drilled on the extreme basin margins and flanking platform areas. The southern Pattani Trough represents a [open quotes]transition zone[close quotes] in terms of potential hydrocarbon prospectivity between the low potential/high exploration risk basin marginal areas, and the high potential/low exploration risk basin marginal area. The development of hydrocarbon accumulationmore » potential within the southern Pattani Trough can be related to a number of major controlling factors. These include structure, which on a regional scale shows a marked influence of tectonic regime on depositional system development, and on a more local scale determines trap development; stratigraphy, which determines reservoir geometry and potential hydrocarbon source rock facies distribution; petrology, which exerts a major control on depth related reservoir quality; overpressure development, which controls local migration pathways for generated hydrocarbons, and locally provides very efficient trap seals; geochemical factors, related to potential source facies distribution, hydrocarbon type; and thermal maturation of the section. The above factors have been combined to define low-, medium-, and high-risk exploration [open quotes]play fairways[close quotes] within the prospectivity transition zone of the southern Pattani Trough.« less

Estimating urban forest carbon sequestration potential in the southern United States using current remote sensing imagery sources

Treesearch

Krista Merry; Pete Bettinger; Jacek Siry; J. Michael Bowker

2015-01-01

With an increased interest in reducing carbon dioxide in the atmosphere, tree planting and maintenance in urban areas has become a viable option for increasing carbon sequestration. Methods for assessing the potential for planting trees within an urban area should allow for quick, inexpensive, and accurate estimations of available land using current remote sensing...

The missing link between submarine volcano and promising geothermal potential in Jinshan, Northern Taiwan

NASA Astrophysics Data System (ADS)

Wang, S. C.; Hutchings, L.; Chang, C. C.; Lee, C. S.

2017-12-01

The Tatun volcanic group (TVG) and the Keelung submarine volcano (KSV) are active volcanoes and surrounding three nuclear plant sites in north Taiwan. The famous Jinshan-Wanli hot springs locates between TVG and KSV, moreover, the geochemical anomalies of acidic boiling springs on the seacoast infer that the origin is from magmatic fluids, sea water and meteoric water mixture, strongly implying that mantle fluids ascends into the shallow crust. The evidence for a magma chamber, submarine volcano, and boiling springs have a close spatial relationship. Based on UNECE specifications to Geothermal Energy Resources (2016), the Jinshan-Wanli geothermal area could be classified as Known Geothermal Energy Source for geothermal direct use and Potential Geothermal Energy Source for conventional geothermal system. High resolution reservoir exploration and modeling in Jinshan-Wanli geothermal area is developing for drilling risk mitigation. The geothermal team of National Taiwan Ocean University and local experts are cooperating for further exploration drilling and geothermal source evaluation. Keywords: geothermal resource evaluation, Jinshan-Wanli geothermal area, submarine volcano

Development of a statistical oil spill model for risk assessment.

PubMed

Guo, Weijun

2017-11-01

To gain a better understanding of the impacts from potential risk sources, we developed an oil spill model using probabilistic method, which simulates numerous oil spill trajectories under varying environmental conditions. The statistical results were quantified from hypothetical oil spills under multiple scenarios, including area affected probability, mean oil slick thickness, and duration of water surface exposed to floating oil. The three sub-indices together with marine area vulnerability are merged to compute the composite index, characterizing the spatial distribution of risk degree. Integral of the index can be used to identify the overall risk from an emission source. The developed model has been successfully applied in comparison to and selection of an appropriate oil port construction location adjacent to a marine protected area for Phoca largha in China. The results highlight the importance of selection of candidates before project construction, since that risk estimation from two adjacent potential sources may turn out to be significantly different regarding hydrodynamic conditions and eco-environmental sensitivity. Copyright © 2017. Published by Elsevier Ltd.

GIS Based Distributed Runoff Predictions in Variable Source Area Watersheds Employing the SCS-Curve Number

NASA Astrophysics Data System (ADS)

Steenhuis, T. S.; Mendoza, G.; Lyon, S. W.; Gerard Marchant, P.; Walter, M. T.; Schneiderman, E.

2003-04-01

Because the traditional Soil Conservation Service Curve Number (SCS-CN) approach continues to be ubiquitously used in GIS-BASED water quality models, new application methods are needed that are consistent with variable source area (VSA) hydrological processes in the landscape. We developed within an integrated GIS modeling environment a distributed approach for applying the traditional SCS-CN equation to watersheds where VSA hydrology is a dominant process. Spatial representation of hydrologic processes is important for watershed planning because restricting potentially polluting activities from runoff source areas is fundamental to controlling non-point source pollution. The methodology presented here uses the traditional SCS-CN method to predict runoff volume and spatial extent of saturated areas and uses a topographic index to distribute runoff source areas through watersheds. The resulting distributed CN-VSA method was incorporated in an existing GWLF water quality model and applied to sub-watersheds of the Delaware basin in the Catskill Mountains region of New York State. We found that the distributed CN-VSA approach provided a physically-based method that gives realistic results for watersheds with VSA hydrology.

Source Water Assessment for the Las Vegas Valley Surface Waters

NASA Astrophysics Data System (ADS)

Albuquerque, S. P.; Piechota, T. C.

2003-12-01

The 1996 amendment to the Safe Drinking Water Act of 1974 created the Source Water Assessment Program (SWAP) with an objective to evaluate potential sources of contamination to drinking water intakes. The development of a Source Water Assessment Plan for Las Vegas Valley surface water runoff into Lake Mead is important since it will guide future work on source water protection of the main source of water. The first step was the identification of the watershed boundary and source water protection area. Two protection zones were delineated. Zone A extends 500 ft around water bodies, and Zone B extends 3000 ft from the boundaries of Zone A. These Zones extend upstream to the limits of dry weather flows in the storm channels within the Las Vegas Valley. After the protection areas were identified, the potential sources of contamination in the protection area were inventoried. Field work was conducted to identify possible sources of contamination. A GIS coverage obtained from local data sources was used to identify the septic tank locations. Finally, the National Pollutant Discharge Elimination System (NPDES) Permits were obtained from the State of Nevada, and included in the inventory. After the inventory was completed, a level of risk was assigned to each potential contaminating activity (PCA). The contaminants of concern were grouped into five categories: volatile organic compounds (VOCs), synthetic organic compounds (SOCs), inorganic compounds (IOCs), microbiological, and radionuclides. The vulnerability of the water intake to each of the PCAs was assigned based on these five categories, and also on three other factors: the physical barrier effectiveness, the risk potential, and the time of travel. The vulnerability analysis shows that the PCAs with the highest vulnerability rating include septic systems, golf courses/parks, storm channels, gas stations, auto repair shops, construction, and the wastewater treatment plant discharges. Based on the current water quality data (prior to treatment), the proximity of Las Vegas Wash to the intake, and the results of the vulnerability analysis of potential contaminating activities, it is determined that the drinking water intake is at a Moderate level of risk for VOC, SOC, and microbiological contaminants. The drinking water intake is at a High level of risk for IOC contaminants. Vulnerability to radiological contamination is Moderate. Source water protection in the Las Vegas Valley is strongly encouraged because of the documented influence of the Las Vegas Wash on the quality of the water at the intake.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bray, R.; Lawrence, S.; Swart, R.

Namibia`s territorial waters occupy a large portion of West Africa`s continental shelf. The area to the 1,000 m isobath is comparable in size to the combined offshore areas of Gabon, Congo, Zaire, and Angola. Around half as much again lies in 1,000--2,500 m of water. The whole unlicensed part of this area will be open for bidding when the Third Licensing Round starts Oct. 1, 1998. Offshore Namibia is underexplored by drilling with only seven exploration wells drilled. Shell`s Kudu field represents a considerable gas resource with reserves of around 3 tcf and is presently the only commercial discovery.Namibia`s offshoremore » area holds enormous exploration potential. Good quality sandstone reservoirs are likely to be distributed widely, and a number of prospective structural and stratigraphic traps have been identified. The recognition of Cretaceous marine oil-prone source rocks combined with the results of new thermal history reconstruction and maturity modeling studies are particularly significant in assessment of the oil potential. The paper discusses resource development and structures, oil source potential, maturity, and hydrocarbon generation.« less

Identifying sources of fugitive emissions in industrial facilities using trajectory statistical methods

NASA Astrophysics Data System (ADS)

Brereton, Carol A.; Johnson, Matthew R.

2012-05-01

Fugitive pollutant sources from the oil and gas industry are typically quite difficult to find within industrial plants and refineries, yet they are a significant contributor of global greenhouse gas emissions. A novel approach for locating fugitive emission sources using computationally efficient trajectory statistical methods (TSM) has been investigated in detailed proof-of-concept simulations. Four TSMs were examined in a variety of source emissions scenarios developed using transient CFD simulations on the simplified geometry of an actual gas plant: potential source contribution function (PSCF), concentration weighted trajectory (CWT), residence time weighted concentration (RTWC), and quantitative transport bias analysis (QTBA). Quantitative comparisons were made using a correlation measure based on search area from the source(s). PSCF, CWT and RTWC could all distinguish areas near major sources from the surroundings. QTBA successfully located sources in only some cases, even when provided with a large data set. RTWC, given sufficient domain trajectory coverage, distinguished source areas best, but otherwise could produce false source predictions. Using RTWC in conjunction with CWT could overcome this issue as well as reduce sensitivity to noise in the data. The results demonstrate that TSMs are a promising approach for identifying fugitive emissions sources within complex facility geometries.

Elevated Arsenic and Uranium Concentrations in Unregulated Water Sources on the Navajo Nation, USA.

PubMed

Hoover, Joseph; Gonzales, Melissa; Shuey, Chris; Barney, Yolanda; Lewis, Johnnye

2017-01-01

Regional water pollution and use of unregulated water sources can be an important mixed metals exposure pathway for rural populations located in areas with limited water infrastructure and an extensive mining history. Using censored data analysis and mapping techniques we analyzed the joint geospatial distribution of arsenic and uranium in unregulated water sources throughout the Navajo Nation, where over 500 abandoned uranium mine sites are located in the rural southwestern United States. Results indicated that arsenic and uranium concentrations exceeded national drinking water standards in 15.1 % (arsenic) and 12.8 % (uranium) of tested water sources. Unregulated sources in close proximity (i.e., within 6 km) to abandoned uranium mines yielded significantly higher concentrations of arsenic or uranium than more distant sources. The demonstrated regional trends for potential co-exposure to these chemicals have implications for public policy and future research. Specifically, to generate solutions that reduce human exposure to water pollution from unregulated sources in rural areas, the potential for co-exposure to arsenic and uranium requires expanded documentation and examination. Recommendations for prioritizing policy and research decisions related to the documentation of existing health exposures and risk reduction strategies are also provided.

MADISON ROADLESS AREA, MONTANA.

USGS Publications Warehouse

Simons, Frank S.; Lambeth, Robert H.

1984-01-01

A mineral-resource survey of the Madison Roadless Area in the Madison Range of southwestern Montana was made. The Madison Roadless Area has demonstrated resources of about 93,000 tons of sillimanite rock at the Placer Creek deposit and of about 83,000 tons of asbestos rock at the Karst deposit. The roadless area also has areas of substantiated phosphate resource potential; much of the phosphate is in thin deeply buried beds. An area near the south edge of the roadless area has a probable resource potential for copper and silver. The concentration of uranium-rich stream-sediment samples in the southwest part of the roadless area suggests that a further attempt to identify the source rocks might be justified.

International Conference on Problems Related to the Stratosphere

NASA Technical Reports Server (NTRS)

Huntress, W., Jr.

1977-01-01

The conference focused on four main areas of investigation: laboratory studies and stratospheric chemistry and constituents, sources for and chemical budget of stratospheric halogen compounds, sources for and chemical budget of stratospheric nitrous oxide, and the dynamics of decision making on regulation of potential pollutants of the stratosphere. Abstracts of the scientific sessions of the conference as well as complete transcriptions of the panel discussions on sources for an atmospheric budget of holocarbons and nitrous oxide are included. The political, social and economic issues involving regulation of potential stratospheric pollutants were examined extensively.

Independent component analysis of EEG dipole source localization in resting and action state of brain

NASA Astrophysics Data System (ADS)

Almurshedi, Ahmed; Ismail, Abd Khamim

2015-04-01

EEG source localization was studied in order to determine the location of the brain sources that are responsible for the measured potentials at the scalp electrodes using EEGLAB with Independent Component Analysis (ICA) algorithm. Neuron source locations are responsible in generating current dipoles in different states of brain through the measured potentials. The current dipole sources localization are measured by fitting an equivalent current dipole model using a non-linear optimization technique with the implementation of standardized boundary element head model. To fit dipole models to ICA components in an EEGLAB dataset, ICA decomposition is performed and appropriate components to be fitted are selected. The topographical scalp distributions of delta, theta, alpha, and beta power spectrum and cross coherence of EEG signals are observed. In close eyes condition it shows that during resting and action states of brain, alpha band was activated from occipital (O1, O2) and partial (P3, P4) area. Therefore, parieto-occipital area of brain are active in both resting and action state of brain. However cross coherence tells that there is more coherence between right and left hemisphere in action state of brain than that in the resting state. The preliminary result indicates that these potentials arise from the same generators in the brain.

Reconciling Biodiversity Conservation and Widespread Deployment of Renewable Energy Technologies in the UK

PubMed Central

Gove, Benedict; Williams, Leah J.; Beresford, Alison E.; Roddis, Philippa; Campbell, Colin; Teuten, Emma; Langston, Rowena H. W.; Bradbury, Richard B.

2016-01-01

Renewable energy will potentially make an important contribution towards the dual aims of meeting carbon emission reduction targets and future energy demand. However, some technologies have considerable potential to impact on the biodiversity of the environments in which they are placed. In this study, an assessment was undertaken of the realistic deployment potential of a range of renewable energy technologies in the UK, considering constraints imposed by biodiversity conservation priorities. We focused on those energy sources that have the potential to make important energy contributions but which might conflict with biodiversity conservation objectives. These included field-scale solar, bioenergy crops, wind energy (both onshore and offshore), wave and tidal stream energy. The spatially-explicit analysis considered the potential opportunity available for each technology, at various levels of ecological risk. The resultant maps highlight the energy resource available, physical and policy constraints to deployment, and ecological sensitivity (based on the distribution of protected areas and sensitive species). If the technologies are restricted to areas which currently appear not to have significant ecological constraints, the total potential energy output from these energy sources was estimated to be in the region of 5,547 TWh/yr. This would be sufficient to meet projected energy demand in the UK, and help to achieve carbon reduction targets. However, we highlight two important caveats. First, further ecological monitoring and surveillance is required to improve understanding of wildlife distributions and therefore potential impacts of utilising these energy sources. This is likely to reduce the total energy available, especially at sea. Second, some of the technologies under investigation are currently not deployed commercially. Consequently this potential energy will only be available if continued effort is put into developing these energy sources/technologies, to enable realisation of their full potential. PMID:27224050

Reconciling Biodiversity Conservation and Widespread Deployment of Renewable Energy Technologies in the UK.

PubMed

Gove, Benedict; Williams, Leah J; Beresford, Alison E; Roddis, Philippa; Campbell, Colin; Teuten, Emma; Langston, Rowena H W; Bradbury, Richard B

2016-01-01

Renewable energy will potentially make an important contribution towards the dual aims of meeting carbon emission reduction targets and future energy demand. However, some technologies have considerable potential to impact on the biodiversity of the environments in which they are placed. In this study, an assessment was undertaken of the realistic deployment potential of a range of renewable energy technologies in the UK, considering constraints imposed by biodiversity conservation priorities. We focused on those energy sources that have the potential to make important energy contributions but which might conflict with biodiversity conservation objectives. These included field-scale solar, bioenergy crops, wind energy (both onshore and offshore), wave and tidal stream energy. The spatially-explicit analysis considered the potential opportunity available for each technology, at various levels of ecological risk. The resultant maps highlight the energy resource available, physical and policy constraints to deployment, and ecological sensitivity (based on the distribution of protected areas and sensitive species). If the technologies are restricted to areas which currently appear not to have significant ecological constraints, the total potential energy output from these energy sources was estimated to be in the region of 5,547 TWh/yr. This would be sufficient to meet projected energy demand in the UK, and help to achieve carbon reduction targets. However, we highlight two important caveats. First, further ecological monitoring and surveillance is required to improve understanding of wildlife distributions and therefore potential impacts of utilising these energy sources. This is likely to reduce the total energy available, especially at sea. Second, some of the technologies under investigation are currently not deployed commercially. Consequently this potential energy will only be available if continued effort is put into developing these energy sources/technologies, to enable realisation of their full potential.

Regional pollution potential in the northwestern United States.

Treesearch

Sue A. Ferguson; Miriam L. Rorig

2003-01-01

The potential for air pollution from industrial sources to reach wilderness areas throughout the Northwestern United States is approximated from monthly mean emissions, along with wind speeds and directions. A simple index is derived to estimate downwind concentration. Maps of pollution potential were generated for each pollution component (particulates, sulfur oxides...

Geochemical characterization of critical dust source regions in the American West

NASA Astrophysics Data System (ADS)

Aarons, Sarah M.; Blakowski, Molly A.; Aciego, Sarah M.; Stevenson, Emily I.; Sims, Kenneth W. W.; Scott, Sean R.; Aarons, Charles

2017-10-01

The generation, transport, and deposition of mineral dust are detectable in paleoclimate records from land, ocean, and ice, providing valuable insight into earth surface conditions and cycles on a range of timescales. Dust deposited in marine and terrestrial ecosystems can provide critical nutrients to nutrient-limited ecosystems, and variations in dust provenance can indicate changes in dust production, sources and transport pathways as a function of climate variability and land use change. Thus, temporal changes in locations of dust source areas and transport pathways have implications for understanding interactions between mineral dust, global climate, and biogeochemical cycles. This work characterizes dust from areas in the American West known for dust events and/or affected by increasing human settlement and livestock grazing during the last 150 years. Dust generation and uplift from these dust source areas depends on climate and land use practices, and the relative contribution of dust has likely changed since the expansion of industrialization and agriculture into the western United States. We present elemental and isotopic analysis of 28 potential dust source area samples analyzed using Thermal Ionization Mass Spectrometry (TIMS) for 87Sr/86Sr and 143Nd/144Nd composition and Multi-Collector Inductively Coupled Plasma Mass Spectrometer (MC-ICPMS) for 176Hf/177Hf composition, and ICPMS for major and trace element concentrations. We find significant variability in the Sr, Nd, and Hf isotope compositions of potential source areas of dust throughout western North America, ranging from 87Sr/86Sr = 0.703699 to 0.740236, εNd = -26.6 to 2.4, and εHf = -21.7 to -0.1. We also report differences in the trace metal and phosphorus concentrations in the geologic provinces sampled. This research provides an important resource for the geochemical tracing of dust sources and sinks in western North America, and will aid in modeling the biogeochemical impacts of increased dust generation and deposition caused by higher drought frequency and human activity.

77 FR 43382 - Millstone Power Station, Unit 2; Exemption

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-24

... sources consisting primarily of fire retardant cable insulation and limited floor based combustibles. The... smoke detectors. The licensee stated that the smoke and heat detection systems were designed and... insulation and that potential ignition sources for these areas includes electrical faults. The licensee...

Hydrological modelling of snail dispersal patterns in Msambweni, Kenya and potential resurgence of Schistosoma haematobium transmission.

PubMed

Clennon, J A; King, C H; Muchiri, E M; Kitron, U

2007-05-01

Urinary schistosomiasis is an important source of human morbidity in Msambweni, Kenya, where the intermediate host snail, Bulinus nasutus is found in ponds and water pools. In the past, aquatic habitats in the area have been studied separately; however, recent collections of B. nasutus snails and shells indicated that many of these ponds are in fact connected during and following sufficient rains. Satellite imagery and a geographical information system (GIS) were used to survey the main water courses and potential drainage routes, to locate potential source populations of snails and to determine probable snail dispersal routes. The 2 water bodies implicated as being the most important Schistosoma haematobium transmission foci in the area were found to differ in their degree of connectivity to other B. nasutus source habitats. One pond becomes connected even after normal rains, while the other pond requires prolonged rains or flooding to become connected with source habitats. Consequently, the transmission foci differ in their susceptibility to snail population control measures. Spatially explicit dispersal models that consider the spatial and temporal patterns of connectivity between aquatic habitats will contribute to improved snail surveillance and more focused control for urinary schistosomiasis at a local level.

Characterization of alluvial dust sources and their temporal development - a multi-sensor approach for the Aïr Massif, Niger

NASA Astrophysics Data System (ADS)

Feuerstein, Stefanie; Schepanski, Kerstin

2017-04-01

One of the world's largest sources of atmospheric dust is the Sahara. It is said that 55% of the total global dust emission can be linked to the desert in northern Africa. Thus, understanding the Saharan dust sources is of great importance to estimate the total global dust load and its variability. Especially one type of dust sources has gained attention in dust research in recent years: The emission of dust from sediments formed by hydrologic processes, so called alluvial dust sources. These sediments were either formed in the past under the influences of a more humid paleoclimate or are deposited recently, e.g. during strong precipitation events when surficial runoff leads to the activation of wadi systems or to the occurrence of flash floods. Especially the latter phenomenon is able to deliver a huge amount of potentially erodible sediments. The research presented here focuses on the characterization of these alluvial dust sources with special attention on their temporal variability in relation to wet and dry phases. A study area covering the Aïr Massif in Niger is analysed over a four years time span from January 2013 to December 2016. The whole cycle from sediment formation to dust emission is illustrated by using data of various satellite sensors that are able to capture the processes taking place at the land surface as well as in the atmosphere: (1) The rainfall distribution for the study area is shown by time series of the TRMM precipitation estimates. A catchment analysis of the area helps to estimate the amount of surficial runoff and to detect areas of potential sediment accumulation. (2) Changes in the sediment structure of the land surface are analysed using atmospherically corrected time series of NASA's Landsat-8 OLI satellite. A land cover classification shows the distribution of alluvial sediments over the area; fresh layers of alluvial deposits are detected. Furthermore, the evolution of the vegetation cover, which inhibits dust emission, is analysed by calculating NDVI time series from the Landsat data. (3) The MSG Dust Product is used to determine the frequency of dust emission from the investigation area. Furthermore, the product allows the precise localization of the sources. Therefore the alluvial sediments can directly be connected to dust emission. By combining the findings of these different satellite sensors, a profound analysis of alluvial dust sources on different levels is possible. The connection between the amount of precipitation and the supply of potentially erodible sediments is shown, which leads to a better understanding of the temporal evolution and importance of this source type.

Nutrient and phytoplankton analysis of a Mediterranean coastal area.

PubMed

Sebastiá, M T; Rodilla, M

2013-01-01

Identifying and quantifying the key anthropogenic nutrient input sources are essential to adopting management measures that can target input for maximum effect in controlling the phytoplankton biomass. In this study, three systems characterized by distinctive main nutrient sources were sampled along a Mediterranean coast transect. These sources were groundwater discharge in the Ahuir area, the Serpis river discharge in the Venecia area, and a submarine wastewater outfall 1,900 m from the coast. The study area includes factors considered important in determining a coastal area as a sensitive area: it has significant nutrient sources, tourism is a major source of income in the region, and it includes an area of high water residence time (Venecia area) which is affected by the harbor facilities and by wastewater discharges. We found that in the Ahuir and the submarine wastewater outfall areas, the effects of freshwater inputs were reduced because of a greater water exchange with the oligotrophic Mediterranean waters. On the other hand, in the Venecia area, the highest levels of nutrient concentration and phytoplankton biomass were attributed to the greatest water residence time. In this enclosed area, harmful dinoflagellates were detected (Alexandrium sp. and Dinophysis caudata). If the planned enlargement of the Gandia Harbor proceeds, it may increase the vulnerability of this system and provide the proper conditions of confinement for the dinoflagellate blooms' development. Management measures should first target phosphorus inputs as this is the most potential-limiting nutrient in the Venecia area and comes from a point source that is easier to control. Finally, we recommend that harbor environmental management plans include regular monitoring of water quality in adjacent waters to identify adverse phytoplankton community changes.

Preliminary assessment of sources of nitrogen in groundwater at a biosolids-application area near Deer Trail

USGS Publications Warehouse

Yager, Tracy J.B.; McMahon, Peter B.

2012-01-01

Concentrations of dissolved nitrite plus nitrate increased fairly steadily in samples from four shallow groundwater monitoring wells after biosolids applications to nonirrigated farmland began in 1993. The U.S. Geological Survey began a preliminary assessment of sources of nitrogen in shallow groundwater at part of the biosolids-application area near Deer Trail, Colorado, in 2005 in cooperation with the Metro Wastewater Reclamation District. Possible nitrogen sources in the area include biosolids, animal manure, inorganic fertilizer, atmospheric deposition, and geologic materials (bedrock and soil). Biosolids from the Metro Wastewater Reclamation District plant in Denver and biosolids, cow manure, geologic materials (bedrock and soil), and groundwater from the study area were sampled to measure nitrogen content and nitrogen isotopic compositions of nitrate or total nitrogen. Biosolids also were leached, and the leachates were analyzed for nitrogen content and other concentrations. Geologic materials from the study area also were sampled to determine mineralogy. Estimates of nitrogen contributed from inorganic fertilizer and atmospheric deposition were calculated from other published reports. The nitrogen information from the study indicates that each of the sources contain sufficient nitrogen to potentially affect groundwater nitrate concentrations. Natural processes can transform the nitrogen in any of the sources to nitrate in the groundwater. Load calculations indicate that animal manure, inorganic fertilizer, or atmospheric deposition could have contributed the largest nitrogen load to the study area in the 13 years before biosolids applications began, but biosolids likely contributed the largest nitrogen load to the study area in the 13 years after biosolids applications began. Various approaches provided insights into sources of nitrate in the groundwater samples from 2005. The isotopic data indicate that, of the source materials considered, biosolids and (or) animal manure were the most likely sources of nitrate in the wells at the time of sampling (2005), and that inorganic fertilizer, atmospheric deposition, and geologic materials were not substantial sources of nitrate in the wells in 2005. The large total nitrogen content of the biosolids and animal-manure samples and biosolids leachates also indicates that the biosolids and animal manure had potential to leach nitrogen and produce large dissolved nitrate concentrations in groundwater. The available data, however, could not be used to distinguish between biosolids or manure as the dominant source of nitrate in the groundwater because the nitrogen isotopic composition of the two materials is similar. Major-ion data also could not be used to distinguish between biosolids or manure as the dominant source of nitrate in the groundwater because the major-ion composition (as well as the isotopic composition) of the two materials is similar. Without additional data, chloride/bromide mass ratios do not necessarily support or refute the hypothesis that biosolids and (or) animal manure were the primary sources of nitrate in water from the study-area wells in 2005. Concentrations of water-extractable nitrate in the soil indicate that biosolids could be an important source of nitrate in the groundwater recharge. Nitrogen inventories in the soil beneath biosolids-application areas and the nitrogen-input estimates for the study area both support the comparisons of isotopic composition, which indicate that some type of human waste (such as biosolids) and (or) animal manure was the source of nitrate in groundwater sampled from the wells in 2005. The nitrogen-load estimates considered with the nitrogen isotopic data and the soil-nitrogen inventories indicate that biosolids applications likely are a major source of nitrogen to the shallow groundwater at these monitoring wells.

Rainwater harvesting and green area retention potential detection using commercial unmanned aerial vehicles

NASA Astrophysics Data System (ADS)

Kamnik, Rok; Grajfoner, Blanka; Butyrin, Andrey; Nekrep Perc, Matjaz

2017-10-01

The objective of this work is to use simple photogrammetry to evaluate rainwater harvesting and green area retention potential in Maribor, Slovenia city centre. Several sources of remote sensing data have been described and a field test with semi-professional drone was performed by means of computer evaluation of rainwater harvesting and green area retention potential. Some of the most important design parameters for rainwater harvesting systems as roof area and slope and available green areas were identified and evaluated. The results have shown that even semi-professional low budget drones can be successfully used for mapping areas of interest. The results of six-minute flight over twelve hectares of Maribor city centre were comparable with professional results of plane remote sensing. Image segmentation from orthomosaic together with elevation model has been used to detect roofs and green areas.

Airborne Quercus pollen in SW Spain: Identifying favourable conditions for atmospheric transport and potential source areas.

PubMed

Maya-Manzano, José María; Fernández-Rodríguez, Santiago; Smith, Matt; Tormo-Molina, Rafael; Reynolds, Andrew M; Silva-Palacios, Inmaculada; Gonzalo-Garijo, Ángela; Sadyś, Magdalena

2016-11-15

The pollen grains of Quercus spp. (oak trees) are allergenic. This study investigates airborne Quercus pollen in SW Spain with the aim identifying favourable conditions for atmospheric transport and potential sources areas. Two types of Quercus distribution maps were produced. Airborne Quercus pollen concentrations were measured at three sites located in the Extremadura region (SW Spain) for 3 consecutive years. The seasonal occurrence of Quercus pollen in the air was investigated, as well as days with pollen concentrations ≥80Pm(-3). The distance that Quercus pollen can be transported in appreciable numbers was calculated using clusters of back trajectories representing the air mass movement above the source areas (oak woodlands), and by using a state-of-the-art dispersion model. The two main potential sources of Quercus airborne pollen captured in SW Spain are Q. ilex subsp. ballota and Q. suber. The minimum distances between aerobiological stations and Quercus woodlands have been estimated as: 40km (Plasencia), 66km (Don Benito), 62km (Zafra) from the context of this study. Daily mean Quercus pollen concentration can exceed 1,700Pm(-3), levels reached not less than 24 days in a single year. High Quercus pollen concentration were mostly associated with moderate wind speed events (6-10ms(-1)), whereas that a high wind speed (16-20ms(-1)) seems to be associated with low concentrations. Copyright © 2016 Elsevier B.V. All rights reserved.

Distribution, fate and risk assessment of PAHs in water and sediments from an aquaculture- and shipping-impacted subtropical lake, China.

PubMed

Zeng, Qingfei; Jeppesen, Erik; Gu, Xiaohong; Mao, Zhigang; Chen, Huihui

2018-06-01

The spatial-temporal distribution of polycyclic aromatic hydrocarbons (PAHs), their source, and potential health risks were determined in overlying water and surface sediments from Chinese Lake Guchenghu, adjacent commercial mitten crab ponds and the connected Wushen Canal to assess the contamination profile of the area. The total PAHs concentrations in sediment and water were 86.7-1790 ng g -1 dry weight (dw) and 184-365 ng L -1 in summer and 184-3140 ng g -1 dw and 410-1160 ng L -1 in winter. Two- and 3-ring PAHs were the predominant compounds in water, while PAHs with 4-6 rings dominated in the sediment at both upstream and downstream sites. PAHs concentrations in water and sediment correlated significantly. Diagnostic ratios and positive matrix factorization (PMF) analyses indicated a strong influence of pyrogenic sources, principally biomass combustion and vehicle emission, on the concentrations of PAHs. The distribution, source identification, and mean effects range median quotients (mERMQ) analyses suggested that the most contaminated area was located downstream and upstream of the Wushen Canal, followed by Lake Guchenghu and a commercial crab pond area. From an ecological point of view, PAHs posed a potential risk to drinking water sources as the concentrations exceeded the guideline value of 0.05 μg L -1 . The risk posed by sediment PAHs appeared to be low except for the downstream sites, which showed a low to medium ecotoxicological risk. The total incremental lifetime cancer risks ranged between 10 -7 and 10 -5 , indicating a potential health risk for the local population when exposed to sediment from the area. Copyright © 2018 Elsevier Ltd. All rights reserved.

Compensatory immigration depends on adjacent population size and habitat quality but not on landscape connectivity.

PubMed

Turgeon, Katrine; Kramer, Donald L

2012-11-01

1. Populations experiencing localized mortality can recover in the short term by net movement of individuals from adjacent areas, a process called compensatory immigration or spillover. Little is known about the factors influencing the magnitude of compensatory immigration or its impact on source populations. Such information is important for understanding metapopulation dynamics, the use of protected areas for conservation, management of exploited populations and pest control. 2. Using two small, territorial damselfish species (Stegastes diencaeus and S. adustus) in their naturally fragmented habitat, we quantified compensatory immigration in response to localized mortality, assessed its impact on adjacent source populations and examined the importance of potential immigrants, habitat quality and landscape connectivity as limiting factors. On seven experimental sites, we repeatedly removed 15% of the initial population size until none remained and immigration ceased. 3. Immigrants replaced 16-72% of original residents in S. diencaeus and 0-69% in S. adustus. The proportion of the source population that immigrated into depleted areas varied from 9% to 61% in S. diencaeus and from 3% to 21% in S. adustus. In S. diencaeus, compensatory immigration was strongly affected by habitat quality, to a lesser extent by the abundance of potential immigrants and not by landscape connectivity. In S. adustus, immigration was strongly affected by the density of potential migrants and not by habitat quality and landscape connectivity. On two control sites, immigration in the absence of creation of vacancies was extremely rare. 4. Immigration occurred in response to localized mortality and was therefore compensatory. It was highly variable, sometimes producing substantial impacts on both depleted and source populations. The magnitude of compensatory immigration was influenced primarily by the availability of immigrants and by the potential improvement in territory quality that they could achieve by immigrating and not by their ability to reach the depleted area. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

Fermi Large Area Telescope third source catalog

DOE PAGES

Acero, F.; Ackermann, M.; Ajello, M.; ...

2015-06-12

Here, we present the third Fermi Large Area Telescope (LAT) source catalog (3FGL) of sources in the 100 MeV–300 GeV range. Based on the first 4 yr of science data from the Fermi Gamma-ray Space Telescope mission, it is the deepest yet in this energy range. Relative to the Second Fermi LAT catalog, the 3FGL catalog incorporates twice as much data, as well as a number of analysis improvements, including improved calibrations at the event reconstruction level, an updated model for Galactic diffuse γ-ray emission, a refined procedure for source detection, and improved methods for associating LAT sources with potential counterparts at other wavelengths. The 3FGL catalog includes 3033 sources abovemore » $$4\\sigma $$ significance, with source location regions, spectral properties, and monthly light curves for each. Of these, 78 are flagged as potentially being due to imperfections in the model for Galactic diffuse emission. Twenty-five sources are modeled explicitly as spatially extended, and overall 238 sources are considered as identified based on angular extent or correlated variability (periodic or otherwise) observed at other wavelengths. For 1010 sources we have not found plausible counterparts at other wavelengths. More than 1100 of the identified or associated sources are active galaxies of the blazar class; several other classes of non-blazar active galaxies are also represented in the 3FGL. Pulsars represent the largest Galactic source class. As a result, from source counts of Galactic sources we estimate that the contribution of unresolved sources to the Galactic diffuse emission is ~3% at 1 GeV.« less

Investigation of the potential source area, contamination pathway, and probable release history of chlorinated-solvent-contaminated groundwater at the Capital City Plume Site, Montgomery, Alabama, 2008-2010

USGS Publications Warehouse

Landmeyer, James E.; Miller, Scott; Campbell, Bruce G.; Vroblesky, Don A.; Gill, Amy C.; Clark, Athena P.

2011-01-01

Detection of the organic solvent perchloroethylene (PCE) in a shallow public-supply well in 1991 and exposure of workers in 1993 to solvent vapors during excavation activities to depths near the water table provided evidence that the shallow aquifer beneath the capital city of Montgomery, Alabama, was contaminated. Investigations conducted from 1993 to 1999 by State and Federal agencies confirmed the detection of PCE in the shallow aquifer, as well as the detection of the organic solvent trichloroethylene (TCE) and various inorganic compounds, but the source of the groundwater contamination was not determined. In May 2000 the U.S. Environmental Protection Agency proposed that the site, called the Capital City Plume (CCP) Site, be a candidate for the National Priorities List. Between 2000 and 2007, numerous site-investigation activities also did not determine the source of the groundwater contamination. In 2008, additional assessments were conducted at the CCP Site to investigate the potential source area, contamination pathway, and the probable release history of the chlorinated-solvent-contaminated groundwater. The assessments included the collection of (1) pore water in 2008 from the hyporheic zone of a creek using passive-diffusion bag samplers; (2) tissue samples in 2008 and 2009 from trees growing in areas of downtown Montgomery characterized by groundwater contamination and from trees growing in riparian zones along the Alabama River and Cypress Creek; and (3) groundwater samples in 2009 and 2010. The data collected were used to investigate the potential source area of contaminants detected in groundwater, the pathway of groundwater contamination, and constraints on the probable contaminant-release history. The data collected between 2008 and 2010 indicate that the PCE and TCE contamination of the shallow aquifer beneath the CCP Site most likely resulted from the past use and disposal of industrial wastewater from printing operations containing chlorinated solvents into the sanitary sewer and (or) stormwater systems of Montgomery. Moreover, chlorinated-solvent use and disposal occurred at least between the 1940s and 1970s at several locations occupied by printing operations. The data also indicate that PCE and TCE contamination continues to occur in the shallow subsurface near potential release areas and that PCE and TCE have been transported to the intermediate part of the shallow aquifer.

Synergies between geomorphic hazard and risk and sediment cascade research fields: exploiting geomorphic processes' susceptibility analyses to derive potential sediment sources in the Oltet, river catchment, southern Romania

NASA Astrophysics Data System (ADS)

Jurchescu, Marta-Cristina

2015-04-01

Identifying sediment sources and sediment availability represents a major problem and one of the first concerns in the field of sediment cascade. This paper addresses the on-site effects associated with sediment transfer, investigating the degree to which studies pertaining to the field of geomorphic hazard and risk research could be exploited in sediment budget estimations. More precisely, the paper investigates whether results obtained in assessing susceptibility to various geomorphic processes (landslides, soil erosion, gully erosion) could be transferred to the study of sediment sources within a basin. The study area is a medium-sized catchment (> 2400 km2) in southern Romania encompassing four different geomorphic units (mountains, hills, piedmont and plain). The region is highly affected by a wide range of geomorphic processes which supply sediments to the drainage network. The presence of a reservoir at the river outlet emphasizes the importance of estimating sediment budgets. The susceptibility analyses are conducted separately for each type of the considered processes in a top-down framework, i.e. at two different scales, using scale-adapted methods and validation techniques in each case, as widely-recognized in the hazard and risk research literature. The analyses start at a regional scale, which has in view the entire catchment, using readily available data on conditioning factors. In a second step, the suceptibility analyses are carried out at a medium scale for selected hotspot-compartments of the catchment. In order to appraise the extent to which susceptibility results are relevant in interpreting sediment sources at catchment scale, scale-induced differences are analysed in the case of each process. Based on the amount of uncertainty revealed by each regional-scale analysis in comparison to the medium-scale ones, decisions are made on whether the first are acceptable to the aim of identifying potential sediment source areas or if they should be refined using more precise methods and input data. The three final basin-wide susceptibility maps are eventually coverted, on a threshold basis, to maps showing the potential areas of sediment production by landslides, soil erosion and gully erosion respectively. These are then combined into one single map of potential sediment sources. The susceptibility assessments indicate that the basin compartments most prone to landslides and soil erosion correspond to the Subcarpathian hills, while the one most threatened by gully erosion corresponds to the piedmont relief. The final map of potential sediment sources shows that approximately 34% of the study catchment is occupied by areas potentially generating sediment through landslides and gully erosion, extending over most of the high piedmont and Subcarpathian hills. The results prove that there is an important link between the two research fields, i.e. geomorphic hazard and risk and sediment cascade, by allowing the transfer of knowledge from geomorphic processes' susceptibility analyses to the estimation of potential sediment sources within catchments. The synergy between the two fields raises further challenges to be tackled in future (e.g. how to derive sediment transfer rates from quantitative hazard estimates).

Tracing suspended sediment sources in the Upper Sangamon River Basin using conservative and non-conservative tracers

NASA Astrophysics Data System (ADS)

Yu, M.; Rhoads, B. L.; Stumpf, A.

2015-12-01

As the awareness of water pollution, eutrophication and other water related environmental concerns grows, the significance of sediment in the transport of nutrients and contaminants from agricultural areas to streams has received increasing attention. Both the physical and geochemical properties of suspended sediment are strongly controlled by sediment sources. Thus, tracing sources of suspended sediment in watersheds is important for the design of management practices to reduce sediment loads and contributions of sediment-adsorbed nutrients from agricultural areas to streams. However, the contributions of different sediment sources to suspended sediment loads within intensively managed watersheds in the Midwest still remain insufficiently explored. This study aims to assess the provenance of suspended sediment and the relation between channel morphology and production of suspended sediment in the Upper Sangamon River Basin, Illinois, USA. The 3,690-km2 Upper Sangamon River Basin is characterized by low-relief, agricultural lands dominated by row-crop agriculture. Sediment source samples were collected in the Saybrook from five potential sources: farmland, forests, floodplains, river banks, and grasslands. Event-based and accumulated suspended sediment samples were collected by ISCO automatic pump samplers and in situ suspended sediment samplers and from the stream at watershed outlet. A quantitative geochemical fingerprinting technique, combining statistically verified multicomponent signatures and an un-mixing model, was employed to estimate the relative contributions of sediment from five potential sources to the suspended sediment loads. Organic matter content, trace elements, and radionuclides from soil samples were used as potential tracers. Our preliminary results indicate that the majority of suspended sediment is derived from floodplains in the downstream portions of the watersheds, while only minor amounts of suspended sediment are derived from upland areas and banks. These results suggest that floodplain erosion during high flow events contributes to the suspended sediment.

Potential sources of nitrous acid (HONO) and their impacts on ozone: A WRF-Chem study in a polluted subtropical region

NASA Astrophysics Data System (ADS)

Zhang, Li; Wang, Tao; Zhang, Qiang; Zheng, Junyu; Xu, Zheng; Lv, Mengyao

2016-04-01

Current chemical transport models commonly undersimulate the atmospheric concentration of nitrous acid (HONO), which plays an important role in atmospheric chemistry, due to the lack or inappropriate representations of some sources in the models. In the present study, we parameterized up-to-date HONO sources into a state-of-the-art three-dimensional chemical transport model (Weather Research and Forecasting model coupled with Chemistry: WRF-Chem). These sources included (1) heterogeneous reactions on ground surfaces with the photoenhanced effect on HONO production, (2) photoenhanced reactions on aerosol surfaces, (3) direct vehicle and vessel emissions, (4) potential conversion of NO2 at the ocean surface, and (5) emissions from soil bacteria. The revised WRF-Chem was applied to explore the sources of the high HONO concentrations (0.45-2.71 ppb) observed at a suburban site located within complex land types (with artificial land covers, ocean, and forests) in Hong Kong. With the addition of these sources, the revised model substantially reproduced the observed HONO levels. The heterogeneous conversions of NO2 on ground surfaces dominated HONO sources contributing about 42% to the observed HONO mixing ratios, with emissions from soil bacterial contributing around 29%, followed by the oceanic source (~9%), photochemical formation via NO and OH (~6%), conversion on aerosol surfaces (~3%), and traffic emissions (~2%). The results suggest that HONO sources in suburban areas could be more complex and diverse than those in urban or rural areas and that the bacterial and/or ocean processes need to be considered in HONO production in forested and/or coastal areas. Sensitivity tests showed that the simulated HONO was sensitive to the uptake coefficient of NO2 on the surfaces. Incorporation of the aforementioned HONO sources significantly improved the simulations of ozone, resulting in increases of ground-level ozone concentrations by 6-12% over urban areas in Hong Kong and the Pearl River Delta region. This result highlights the importance of accurately representing HONO sources in simulations of secondary pollutants over polluted regions.

Complex watersheds, collaborative teams: Assessing pollutant presence and effects in the San Francisco Delta

EPA Science Inventory

There is a great diversity of sources of chemical contaminants and stressors over large geographic areas. Chemical contaminant inputs and magnitude can potentially exhibit wide seasonal variation over large geographic areas. Together, these factors make linking exposure to monito...

Impacts on groundwater recharge areas of megacity pumping: analysis of potential contamination of Kolkata, India, water supply

USGS Publications Warehouse

Sahu, Paulami; Michael, Holly A.; Voss, Clifford I.; Sikdar, Pradip K.

2013-01-01

Water supply to the world's megacities is a problem of quantity and quality that will be a priority in the coming decades. Heavy pumping of groundwater beneath these urban centres, particularly in regions with low natural topographic gradients, such as deltas and floodplains, can fundamentally alter the hydrological system. These changes affect recharge area locations, which may shift closer to the city centre than before development, thereby increasing the potential for contamination. Hydrogeological simulation analysis allows evaluation of the impact on past, present and future pumping for the region of Kolkata, India, on recharge area locations in an aquifer that supplies water to over 13 million people. Relocated recharge areas are compared with known surface contamination sources, with a focus on sustainable management of this urban groundwater resource. The study highlights the impacts of pumping on water sources for long-term development of stressed city aquifers and for future water supply in deltaic and floodplain regions of the world.

Perceptual reversals during binocular rivalry: ERP components and their concomitant source differences.

PubMed

Britz, Juliane; Pitts, Michael A

2011-11-01

We used an intermittent stimulus presentation to investigate event-related potential (ERP) components associated with perceptual reversals during binocular rivalry. The combination of spatiotemporal ERP analysis with source imaging and statistical parametric mapping of the concomitant source differences yielded differences in three time windows: reversals showed increased activity in early visual (∼120 ms) and in inferior frontal and anterior temporal areas (∼400-600 ms) and decreased activity in the ventral stream (∼250-350 ms). The combination of source imaging and statistical parametric mapping suggests that these differences were due to differences in generator strength and not generator configuration, unlike the initiation of reversals in right inferior parietal areas. These results are discussed within the context of the extensive network of brain areas that has been implicated in the initiation, implementation, and appraisal of bistable perceptual reversals. Copyright © 2011 Society for Psychophysiological Research.

United States Air Force 611th Civil Engineer Squadron, Elmendorf, AFB, Alaska. Final engineering evaluation/cost analysis, million gallon hill source area of the West Unit, Galena Airport, Alaska

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-02-05

This decision document presents the selected removal action for the Million Gallon Hill source area of the Installation Restoration Program (IRP) site ST009, otherwise known as the West Unit at Galena Airport, Alaska. The information from the RI Report is summarized, along with an analysis of potential removal action alternatives in the Engineering Evaluation/Cost Analysis (EE/CA).

Potential industrial sites in the Lynn Canal area, Alaska

USGS Publications Warehouse

Johnson, Arthur; Twenhofel, William Stephens

1953-01-01

Full development of a proposal to divert the headwaters of the Yukon River drainage from Canada into the Taiya River valley of Alaska would make available more than a half million kilowatts of electrical energy. Utilization of this block of power, for which there is at present no local market, will require an industrial and community development of appreciable magnitude. Suitable sites for industrial and community development near the proposed power source are limited because of the extremely rugged and mountainous terrain of the Lynn Canal area. This report considers potential industrial areas at Skagway, Taiya River, Ferebee River, Lutak Inlet, Haines and vicinity, Klukwan and vicinity, Haines to Klukwan along the Haines cutoff, Berners Bay, and Juneau and vicinity. The factors considered in their evaluation are topography, geology, climate, water supply, transportation facilities, and transmission-line routes from the source of power.

Highly contaminated areas as sources of pollution for adjoining ecosystems: The case of Augusta Bay (Central Mediterranean).

PubMed

Di Leonardo, R; Mazzola, A; Tramati, C D; Vaccaro, A; Vizzini, S

2014-12-15

An assessment of trace element and polycyclic aromatic hydrocarbon (PAH) contamination based on surface sediments collected in summer 2012 was carried out in Priolo Bay adjoining one of the most polluted areas of the Mediterranean Sea, the industrial Augusta harbour (Italy, Central Mediterranean). Inorganic and organic contaminants were generally not remarkable. Occasional elevated concentrations of Hg, Cd, Ni and PAHs exceeding sediment quality guidelines were detected in the northern sector of Priolo Bay, close to Augusta harbour, possibly as a result of water drainage of industrialised and urbanised areas and/or potential direct export of contaminated material from Augusta harbour, whose influence on the adjoining Priolo Bay ecosystem cannot be ruled out. By domino effect, Priolo sediments may therefore become a potential source of pollutants and may represent a threat to the biota. Copyright © 2014 Elsevier Ltd. All rights reserved.

Potential role of remote sensing in disaster relief management

NASA Technical Reports Server (NTRS)

Rush, M.; Holguin, A.; Vernon, S.

1976-01-01

Baseline or predisaster data which would be useful to decision making in the immediate postdisaster period were suggested for the six areas of public health concern along with guidelines for organizing these data. Potential sources of these data are identified. In order to fully assess the impact of a disaster on an area, information about its predisaster status must be known. Aerial photography is one way of acquiring and recording such data.

Polycyclic aromatic hydrocarbons in soils from urban to rural areas in Nanjing: Concentration, source, spatial distribution, and potential human health risk.

PubMed

Wang, Chunhui; Wu, Shaohua; Zhou, Sheng Lu; Wang, Hui; Li, Baojie; Chen, Hao; Yu, Yanna; Shi, Yaxing

2015-09-15

Polycyclic aromatic hydrocarbons (PAHs) have become a major type of pollutant in urban areas and their degree of pollution and characteristics of spatial distribution differ between various regions. We conducted a comprehensive study about the concentration, source, spatial distribution, and health risk of 16 PAHs from urban to rural soils in Nanjing. The mean total concentrations of 16 PAHs (∑16PAHs) were 3330 ng g(-1) for urban soils, 1680 ng g(-1) for suburban soils, and 1060 ng g(-1) for rural soils. Five sources in urban, suburban, and rural areas of Nanjing were identified by positive matrix factorization. Their relative contributions of sources to the total soil PAH burden in descending order was coal combustion, vehicle emissions, biomass burning, coke tar, and oil in urban areas; in suburban areas the main sources of soil PAHs were gasoline engine and diesel engine, whereas in rural areas the main sources were creosote and biomass burning. The spatial distribution of soil PAH concentrations shows that old urban districts and commercial centers were the most contaminated of all areas in Nanjing. The distribution pattern of heavier PAHs was in accordance with ∑16PAHs, whereas lighter PAHs show some special characteristics. Health risk assessment based on toxic equivalency factors of benzo[a]pyrene indicated a low concentration of PAHs in most areas in Nanjing, but some sensitive sites should draw considerable attention. We conclude that urbanization has accelerated the accumulation of soil PAHs and increased the environmental risk for urban residents. Copyright © 2015. Published by Elsevier B.V.

Composite analysis E-area vaults and saltstone disposal facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cook, J.R.

1997-09-01

This report documents the Composite Analysis (CA) performed on the two active Savannah River Site (SRS) low-level radioactive waste (LLW) disposal facilities. The facilities are the Z-Area Saltstone Disposal Facility and the E-Area Vaults (EAV) Disposal Facility. The analysis calculated potential releases to the environment from all sources of residual radioactive material expected to remain in the General Separations Area (GSA). The GSA is the central part of SRS and contains all of the waste disposal facilities, chemical separations facilities and associated high-level waste storage facilities as well as numerous other sources of radioactive material. The analysis considered 114 potentialmore » sources of radioactive material containing 115 radionuclides. The results of the CA clearly indicate that continued disposal of low-level waste in the saltstone and EAV facilities, consistent with their respective radiological performance assessments, will have no adverse impact on future members of the public.« less

Relative importance of atmospheric and riverine mercury sources to the northern Gulf of Mexico.

PubMed

Rice, Glenn E; Senn, David B; Shine, James P

2009-01-15

A box model was developed to quantify the major sources and dominant fates of inorganic mercury (Hg) in the Mississippi River-influenced area of the northern Gulf of Mexico (nGOM). Riverine (75%) and direct atmospheric deposition (25%) deliver 9.7 t Hg y(-1) to this productive fishery; most (80%) accumulates in bottom sediments where it can be methylated and enter foodwebs. Although riverine inputs dominate atmospheric deposition, 75% of the riverine sediment-associated Hg accumulates in only approximately 8% of the study area. Atmospheric deposition can explain most of the Hg accumulating in sediments of the remaining area. Considering the differences in temporal responsiveness of riverine (centuries) and atmospheric (years) Hg inputs to anthropogenic emissions changes, the spatial limits of the riverine Hg source andthe potential dominance of atmospheric deposition over large areas could have implications for the timing of benefits from policies reducing anthropogenic Hg emissions.

Hydrologic reconnaissance evaluation of the Federal Capital Territory and surrounding areas, Nigeria

USGS Publications Warehouse

Peterson, L.R.; Meyer, Gerald

1977-01-01

Initial moderate water requirements of the new Federal Capital Territory in Central Nigeria are available from the two large rivers, the Niger and Benue, from the smaller Gurara River, and possibly from several smaller streams. Ground water in the southwestern part of the Territory and in adjacent areas along the Niger River is also a potential source. The Niger and Benue Rivers are obvious sources of major supply for eventual large demands, and the Gurara River and sedimentary aquifers also may have that potential. Available data are sparse and highly inadequate for satisfactory design of assessment, development, and management plans for the Territory. Initiation of systematic investigation and collection of data at an early date is recommended. (Woodard-USGS)

Increasing biochar surface area: effects of various milling

USDA-ARS?s Scientific Manuscript database

Biochar produced from corn stover is a renewable, plentiful source of carbon that is a potential substitute for carbon black as rubber composite filler and also as binder/filter media for water or beverage purification applications. However, to be successful in these applications, the surface area o...

Risk assessment and source analysis of soil heavy metal pollution from lower reaches of Yellow River irrigation in China.

PubMed

Zhang, Pengyan; Qin, Chengzhe; Hong, Xin; Kang, Guohua; Qin, Mingzhou; Yang, Dan; Pang, Bo; Li, Yanyan; He, Jianjian; Dick, Richard P

2018-08-15

The level of concentration of heavy metal in soil is detrimental to soil quality. The Heigangkou-Liuyuankou irrigation area in the lower-reach of Yellow River irrigation, as home to a large population and a major site to agricultural production, is vulnerable to heavy metal pollution. This study examined soil quality in Heigangkou-Liuyuankou irrigation areas of Kaifeng, China. Pollution in soil and potential risks introduced by heavy metal accumulation were assessed using Nemerow, Geoaccumulation, and Hakanson's ecological risk indices. Statistics and Geographic Information Systems (GIS) were used to model and present the spatiotemporal changes of the pollution sources and factors affecting the levels of pollution. The heavy metals found in the sampled soil are Cr, Ni, Cu, Zn, Cd, Pb, As, and Hg. Among them, Cd is more concentrated than the others. The southwestern region of the studied area confronts the most serious heavy metal pollution. There exist spatial disparities of low concentrations of different heavy metals in the study area. Hg and Cd are found to pose the highest potential ecological risks. However, their risk levels are not the same across the study area. Levels concentration of Ni, Cu, Zn, Cd, Pb, As, and Hg in soil are highly correlated. In combination, they post an additional threat to the ecological environment. Transportation, rural settlements, and water bodies are found to be the major sources of Cr, Ni, Cu, Zn, Cd, Pb, and Hg pollution in the soil; among the major sources, transportation is the most significant factor. Copyright © 2018 Elsevier B.V. All rights reserved.

Spatial variability in airborne bacterial communities across land-use types and their relationship to the bacterial communities of potential source environments

PubMed Central

Bowers, Robert M; McLetchie, Shawna; Knight, Rob; Fierer, Noah

2011-01-01

Although bacteria are ubiquitous in the near-surface atmosphere and they can have important effects on human health, airborne bacteria have received relatively little attention and their spatial dynamics remain poorly understood. Owing to differences in meteorological conditions and the potential sources of airborne bacteria, we would expect the atmosphere over different land-use types to harbor distinct bacterial communities. To test this hypothesis, we sampled the near-surface atmosphere above three distinct land-use types (agricultural fields, suburban areas and forests) across northern Colorado, USA, sampling five sites per land-use type. Microbial abundances were stable across land-use types, with ∼105–106 bacterial cells per m3 of air, but the concentrations of biological ice nuclei, determined using a droplet freezing assay, were on average two and eight times higher in samples from agricultural areas than in the other two land-use types. Likewise, the composition of the airborne bacterial communities, assessed via bar-coded pyrosequencing, was significantly related to land-use type and these differences were likely driven by shifts in the sources of bacteria to the atmosphere across the land-uses, not local meteorological conditions. A meta-analysis of previously published data shows that atmospheric bacterial communities differ from those in potential source environments (leaf surfaces and soils), and we demonstrate that we may be able to use this information to determine the relative inputs of bacteria from these source environments to the atmosphere. This work furthers our understanding of bacterial diversity in the atmosphere, the terrestrial controls on this diversity and potential approaches for source tracking of airborne bacteria. PMID:21048802

The role of livestock-poached pasture as a sediment source

NASA Astrophysics Data System (ADS)

Greenwood, Philip; Walling, Desmond; Quine, Timothy

2015-04-01

Historically, the occurrence of sediment-laden runoff has almost exclusively been associated with cultivated hillslopes and particularly with arable land. This association was commonly accompanied by the presumption that, in comparison with cultivated slopes, erosion from intensively-managed lowland pasture was relatively low. Recent developments in sediment source tracing and fingerprinting techniques have, however, challenged these assumptions by demonstrating that soil loss from grasslands may be greater than previously assumed. In attempting to identify potential source areas within grassland environments, attention has frequently focused on areas of livestock poaching where herd animals tend to congregate. However, the role of poached grassland as a sediment-source remains uncertain. Reasons include the difficulties associated with accurately documenting the movement or redistribution of small quantities of fine sediment over relevant spatial and temporal scales. Motivated by an urgent need for such information, this communication presents preliminary results from a tracing study aimed at measuring sediment redistribution within areas of poached pasture over short (i.e. event-based) timescales using the artificial radionuclides, caesium-134 (134Cs) and cobalt-60 (60Co). The approach involved labelling six small areas (0.2 * 0.2 m) of poached soil, each with a contrasting gradient, with either 134Cs or 60Co, and then measuring changes in the radiometric inventory at predetermined points before and after periods of rainfall. Each labelled area of poached pasture was measured on three separate occasions over a 65 day period. At the end of the monitoring phase, the mean net soil redistribution depth (mm) was negative for all plots, with values ranging from -6.8 mm to -15.2 mm. This is interpreted as evidence of the removal, or erosion, of surface material. The findings indicate that areas of livestock-poached pasture can act as significant sediment sources. These findings are discussed with regard to the potential contribution of poaching to the off-site transfer of fine-sediment from affected grasslands, and to the implications for the water quality of receiving streams.

Exploratory study of atmospheric methane enhancements derived from natural gas use in the Houston urban area

DOE PAGES

Sanchez, Nancy P.; Zheng, Chuantao; Ye, Weilin; ...

2018-01-04

Here, the extensive use of natural gas (NG) in urban areas for heating, cooking and as a vehicular fuel is associated with potentially significant emissions of methane (CH 4) to the atmosphere. Methane, a potent greenhouse gas that influences the chemistry of the atmosphere, can be emitted from different sources including leakage from NG infrastructure, transportation activities, end-use uncombusted NG, landfills and livestock. Although significant CH 4 leakage associated with aging local NG distribution systems in the U.S. has been reported, further investigation is required to study the role of this infrastructure component and other NG-related sources in atmospheric CHmore » 4 enhancements in urban centers. In this study, neighborhood-scale mobile-based monitoring of potential CH 4 emissions associated with NG in the Greater Houston area (GHA) is reported. A novel dual-gas 3.337 μm interband cascade laser-based sensor system was developed and mobile-mode deployed for simultaneous CH 4 and ethane (C 2H 6) monitoring during a period of over 14 days, corresponding to ~ 90 hours of effective data collection during summer 2016. The sampling campaign covered ~ 250 road miles and was primarily concentrated on eight residential zones with distinct infrastructure age and NG usage levels. A moderate number of elevated CH 4 concentration events (37 episodes) with mixing ratios not exceeding 3.60 ppmv and associated with atmospheric background enhancements below 1.21 ppmv were observed during the field campaign. Source discrimination analyses based on the covariance between CH 4 and C 2H 6 levels indicated the predominance of thermogenic sources (e.g., NG) in the elevated CH 4 concentration episodes. The volumetric fraction of C 2H 6 in the sources associated with the thermogenic CH 4 spikes varied between 2.7 and 5.9%, concurring with the C 2H 6 content in NG distributed in the GHA. Isolated CH 4 peak events with significantly higher C 2H 6 enhancements (~11 %) were observed at industrial areas and locations with high density of petroleum and gas pipelines in the GHA, indicating potential variability in Houston’s thermogenic CH 4 sources.« less

Use of Nitrogen-15 Isotope Method in Soils and Ground Water to Determine Potential Nitrogen Sources Affecting a Municipal Water Supply in Kansas, USA

NASA Astrophysics Data System (ADS)

Townsend, M. A.; Macko, S. A.

2004-12-01

Nitrate-N concentrations have increased to greater than 10 mg/L in a municipal water supply in western Kansas from 1995 to 2002. A study was done by the Kansas Geological Survey using the nitrogen-15 natural abundance isotope method to determine potential sources for the increasing nitrate concentrations. Preliminary results of the isotope analyses on water samples suggest that animal waste and/or denitrification enrichment has affected the water supply. Soil samples from areas near the wells that were not treated with manure show a general increase of nitrogen-15 signature (+9 to +15 \\permil) to a depth of 5 m. Soils are silt loams with measurable carbonate (0.8 to 2 % by weight) in the profile, which may permit volatilization enrichment to occur in the soil profile. Wells in the area range from 11 to 20 m in alluvial deposits with depth to water at approximately 9 m). Nitrate-N values range from 8 to 26 mg/L. Nitrogen-15 values range from (+17 to +28 \\permil) with no obvious source of animal waste near the well sites. There are potential nearby long-term sources of animal waste - an abandoned sewage treatment plant and an agricultural testing farm. One well has a reducing chemistry with a nitrate value of 0.9 mg/L and a nitrogen-15 value of +17 \\permil suggesting that alluvial sediment variation also has an impact on the water quality in the study area. The other wells show values of nitrate and nitrogen-15 that are much greater than the associated soils. The use of nitrogen-15 alone permited limited evaluation of sources of nitrate to ground water particularly in areas with carbonate in the soils. Use of oxygen-18 on nitrate will permit the delineation of the processes affecting the nitrogen in the soil profile and determination of the probable sources and the processes that have affected the nitrogen in the ground water. Final results of the nitrogen-15 and oxygen-18 analyses will be presented.

Exploratory study of atmospheric methane enhancements derived from natural gas use in the Houston urban area

NASA Astrophysics Data System (ADS)

Sanchez, Nancy P.; Zheng, Chuantao; Ye, Weilin; Czader, Beata; Cohan, Daniel S.; Tittel, Frank K.; Griffin, Robert J.

2018-03-01

The extensive use of natural gas (NG) in urban areas for heating and cooking and as a vehicular fuel is associated with potentially significant emissions of methane (CH4) to the atmosphere. Methane, a potent greenhouse gas that influences the chemistry of the atmosphere, can be emitted from different sources including leakage from NG infrastructure, transportation activities, end-use uncombusted NG, landfills and livestock. Although significant CH4 leakage associated with aging local NG distribution systems in the U.S. has been reported, further investigation is required to study the role of this infrastructure component and other NG-related sources in atmospheric CH4 enhancements in urban centers. In this study, neighborhood-scale mobile-based monitoring of potential CH4 emissions associated with NG in the Greater Houston area (GHA) is reported. A novel dual-gas 3.337 μm interband cascade laser-based sensor system was developed and mobile-mode deployed for simultaneous CH4 and ethane (C2H6) monitoring during a period of over 14 days, corresponding to ∼ 90 h of effective data collection during summer 2016. The sampling campaign covered ∼250 exclusive road miles and was primarily concentrated on eight residential zones with distinct infrastructure age and NG usage levels. A moderate number of elevated CH4 concentration events (37 episodes) with mixing ratios not exceeding 3.60 ppmv and associated with atmospheric background enhancements below 1.21 ppmv were observed during the field campaign. Source discrimination analyses based on the covariance between CH4 and C2H6 levels indicated the predominance of thermogenic sources (e.g., NG) in the elevated CH4 concentration episodes. The volumetric fraction of C2H6 in the sources associated with the thermogenic CH4 spikes varied between 2.7 and 5.9%, concurring with the C2H6 content in NG distributed in the GHA. Isolated CH4 peak events with significantly higher C2H6 enhancements (∼11%) were observed at industrial areas and locations with high density of petroleum and gas pipelines in the GHA, indicating potential variability in Houston's thermogenic CH4 sources.

Exploratory study of atmospheric methane enhancements derived from natural gas use in the Houston urban area

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanchez, Nancy P.; Zheng, Chuantao; Ye, Weilin

Here, the extensive use of natural gas (NG) in urban areas for heating, cooking and as a vehicular fuel is associated with potentially significant emissions of methane (CH 4) to the atmosphere. Methane, a potent greenhouse gas that influences the chemistry of the atmosphere, can be emitted from different sources including leakage from NG infrastructure, transportation activities, end-use uncombusted NG, landfills and livestock. Although significant CH 4 leakage associated with aging local NG distribution systems in the U.S. has been reported, further investigation is required to study the role of this infrastructure component and other NG-related sources in atmospheric CHmore » 4 enhancements in urban centers. In this study, neighborhood-scale mobile-based monitoring of potential CH 4 emissions associated with NG in the Greater Houston area (GHA) is reported. A novel dual-gas 3.337 μm interband cascade laser-based sensor system was developed and mobile-mode deployed for simultaneous CH 4 and ethane (C 2H 6) monitoring during a period of over 14 days, corresponding to ~ 90 hours of effective data collection during summer 2016. The sampling campaign covered ~ 250 road miles and was primarily concentrated on eight residential zones with distinct infrastructure age and NG usage levels. A moderate number of elevated CH 4 concentration events (37 episodes) with mixing ratios not exceeding 3.60 ppmv and associated with atmospheric background enhancements below 1.21 ppmv were observed during the field campaign. Source discrimination analyses based on the covariance between CH 4 and C 2H 6 levels indicated the predominance of thermogenic sources (e.g., NG) in the elevated CH 4 concentration episodes. The volumetric fraction of C 2H 6 in the sources associated with the thermogenic CH 4 spikes varied between 2.7 and 5.9%, concurring with the C 2H 6 content in NG distributed in the GHA. Isolated CH 4 peak events with significantly higher C 2H 6 enhancements (~11 %) were observed at industrial areas and locations with high density of petroleum and gas pipelines in the GHA, indicating potential variability in Houston’s thermogenic CH 4 sources.« less

Sources and geographic origin of particulate matter in urban areas of the Danube macro-region: The cases of Zagreb (Croatia), Budapest (Hungary) and Sofia (Bulgaria).

PubMed

Perrone, M G; Vratolis, S; Georgieva, E; Török, S; Šega, K; Veleva, B; Osán, J; Bešlić, I; Kertész, Z; Pernigotti, D; Eleftheriadis, K; Belis, C A

2018-04-01

The contribution of main PM pollution sources and their geographic origin in three urban sites of the Danube macro-region (Zagreb, Budapest and Sofia) were determined by combining receptor and Lagrangian models. The source contribution estimates were obtained with the Positive Matrix Factorization (PMF) receptor model and the results were further examined using local wind data and backward trajectories obtained with FLEXPART. Potential Source Contribution Function (PSCF) analysis was applied to identify the geographical source areas for the PM sources subject to long-range transport. Gas-to-particle transformation processes and primary emissions from biomass burning are the most important contributors to PM in the studied sites followed by re-suspension of soil (crustal material) and traffic. These four sources can be considered typical of the Danube macro-region because they were identified in all the studied locations. Long-range transport was observed of: a) sulphate-enriched aged aerosols, deriving from SO 2 emissions in combustion processes in the Balkans and Eastern Europe and b) dust from the Saharan and Karakum deserts. The study highlights that PM pollution in the studied urban areas of the Danube macro-region is the result of both local sources and long-range transport from both EU and no-EU areas. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Establishment of Groundwater Arsenic Potential Distribution and Discrimination in Taiwan

NASA Astrophysics Data System (ADS)

Tsai, Kuo Sheng; Chen, Yu Ying; Chung Liu, Chih; Lin, Chien Wen

2016-04-01

According to the last 10 years groundwater monitoring data in Taiwan, Arsenic concentration increase rapidly in some areas, similar to Bengal and India, the main source of Arsenic-polluted groundwater is geological sediments, through reducing reactions. There are many researches indicate that high concentration of Arsenic in groundwater poses the risk to water safety, for example, the farm lands irrigation water contains Arsenic cause the concentration of Arsenic increase in soil and crops. Based on the management of water usage instead of remediation in the situation of insufficient water. Taiwan EPA has been developed the procedures of Arsenic contamination potential area establishment and source discriminated process. Taiwan EPA use the procedures to determine the management of using groundwater, and the proposing usage of Arsenic groundwater accordance with different objects. Agencies could cooperate with the water quality standard or water needs, studying appropriate water purification methods and the groundwater depth, water consumption, thus achieve the goal of water safety and environmental protection, as a reference of policy to control total Arsenic concentration in groundwater. Keywords: Arsenic; Distribution; Discrimination; Pollution potential area of Arsenic; Origin evaluation of groundwater Arsenic

Developments and potential of radiation processing in the Philippines

NASA Astrophysics Data System (ADS)

Singson, C.; Carmona, C.

This paper describes the research and development activities in three areas of radiation processing, namely: food irradiation, medical product sterilization and wood plastic combination. Plans and efforts exerted to acquire a larger gamma source to augment our present 5,000 curie source are discussed. Cost estimates for a radiation facility is presented on the basis of the market potential of food irradiation and medical product sterilization. Existing local industries that can benefit from the adaptation of irradiation technology in their processing requirements is described.

Surface water polycyclic aromatic hydrocarbons (PAH) in urban areas of Nanjing, China.

PubMed

Wang, Chunhui; Zhou, Shenglu; Wu, Shaohua; Song, Jing; Shi, Yaxing; Li, Baojie; Chen, Hao

2017-10-01

The concentration, sources and environmental risks of polycyclic aromatic hydrocarbons (PAHs) in surface water in urban areas of Nanjing were investigated. The range of ∑ 16 PAHs concentration is between 4,076 and 29,455 ng/L, with a mean of 17,212 ng/L. The composition of PAHs indicated that 2- and 3-ring PAHs have the highest proportion in all PAHs, while the 5- and 6-ring PAHs were the least in proportion. By diagnostic ratio analysis, combustion and petroleum were a mixture input that contributed to the water PAH in urban areas of Nanjing. Positive matrix factorization quantitatively identified four factors, including coke oven, coal combustion, oil source, and vehicle emission, as the main sources. Toxic equivalency factors of BaP (BaP eq ) evaluate the environmental risks of PAHs and indicate the PAH concentration in surface water in urban areas of Nanjing had been polluted and might cause potential environmental risks. Therefore, the PAH contamination in surface water in urban areas of Nanjing should draw considerable attention.

Identification of nitrate sources in groundwater and potential impact on drinking water reservoir (Goczałkowice reservoir, Poland)

NASA Astrophysics Data System (ADS)

Czekaj, Joanna; Jakóbczyk-Karpierz, Sabina; Rubin, Hanna; Sitek, Sławomir; Witkowski, Andrzej J.

2016-08-01

Goczałkowice dammed reservoir (area - 26 km2) is a strategic object for flood control in the Upper Vistula River catchment and one of the most important source of drinking water in the Upper Silesian Industrial Region (Southern Poland). Main aims of the investigation were identification of sources of nitrate and assessment of their significance in potential risk to groundwater quality. In the catchment area monitoring network of 22 piezometers, included 14 nested, have been installed. The significant spatial and seasonal differences in chemical composition between northern and southern part of the catchment were indicated based on the groundwater sampling conducted twice - in autumn 2011 and spring 2012. Maximum observed concentrations of nitrate were identified in northern part of the study area 255 mg/L as a results of inappropriate sewage management and agriculture activity. Results, based on the combines multi-scale hydrogeological and hydrochemical field studies, groundwater flow and transport modelling, dual stable isotope approach and geochemical modelling indicate mainly agriculture and inappropriate sewage water management as a sources of NO3- contamination of groundwater which moreover is affected by geochemical processes. In general, contaminated groundwater does not impact surface water quality. However, due to high concentration of nitrate in northern part a continues measurements of nitrogen compounds should be continued and used for reducing uncertainty of the predictive scenarios of the mass transport modelling in the study area.

Identification of potential wetlands in training areas on Ravenna Army Ammunition Plant, Ohio, and guidelines for their management

USGS Publications Warehouse

Schalk, C.W.; Tertuliani, J.S.; Darner, R.A.

1999-01-01

Potential wetlands in training areas on Ravenna Army Ammunition Plant, Ohio, were mapped by use of geographic information system (GIS) data layers and field inspection. The GIS data layers were compiled from existing sources and interpretation of aerial photography. Data layers used in the GIS analysis were wetland-plant communities, hydric soils, National Wetlands Inventory designated areas, and wet areas based on photogrammetry. According to review of these data layers, potential wetlands constitute almost one-third of the land in the training areas. A composite map of these four data layers was compiled for use during inspection of the training areas. Field inspection focused on the presence of hydrophytic vegetation and macroscopic evidences of wetland hydrology. Results of the field inspection were in general agreement with those predicted by the GIS analysis, except that some wet areas were more extensive than predicted because of high amounts of precipitation during critical periods of 1995 and 1996. Guidelines for managing wetlands in the training areas are presented.

Increasing biochar surface area: Optimization of ball milling parameters

USDA-ARS?s Scientific Manuscript database

Biochar produced from corn stover is a renewable, plentiful source of carbon that is a potential substitute for carbon black as rubber composite filler and also as binder/filter media for water or beverage purification applications. However, to be successful in these applications, the surface area o...

Water resources of the Grand Rapids area, Michigan

USGS Publications Warehouse

Stramel, G.J.; Wisler, C.O.; Laird, L.B.

1954-01-01

The Grand Rapids area, Michigan, has three sources from which to obtain its water supply: Lake Michigan, the Grand River and its tributaries, and ground water. Each of the first two and possibly the third is capable of supplying the entire needs of the area.This area is now obtaining a part of its supply from each of these sources. Of the average use of 50 mgd (million gallons per day) during 1951, Lake Michigan supplied 29 mgd; the Grand River and its tributaries supplied 1 mgd; and ground water supplied 20 mgd.Lake Michigan offers a practically unlimited source of potable water. However, the cost of delivery to the Grand Rapids area presents an economic problem in the further development of this source. Even without storage the Grand River can provide an adequate supply for the city of Grand Rapids. The present average use of the city of Grand Rapids is about 30 mgd and the maximum use is about 60 mgd, while the average flow of the Grand River is 2, 495 mgd or 3, 860 cfs (cubic feet per second) and the minimum daily flow recorded is 246 mgd. The quality and temperature of water in the Grand River is less desirable than Lake Michigan water. However, with proper treatment its chemical quality can be made entirely satisfactory.The city of Grand Rapids is actively engaged in a study that will lead to the expansion of its present water-supply facilities to meet the expected growth in population in Grand Rapids and its environs.Ground-water aquifers in the area are a large potential source of supply. The Grand Rapids area is underlain by glacial material containing a moderately hard to very hard water of varying chemical composition but suitable for most uses. The glacial outwash and lacustrine deposits bordering principal streams afford the greatest potential for the development of large supplies of potable ground water. Below the glacial drift, bedrock formations contain water that is extremely hard and moderately to highly mineralized. Thus the major sources of usable ground water are the glacial drift and some parts of the bedrock. Wherever the bedrock yields large quantities of water, the water is generally of inferior quality. Any development should be preceded by test drilling and careful hydrologic and geologic studies of the area under consideration and chemical analysis of the water found.

REMEDIATION FLUID RECYCLING - APPLICATION OF PERVAPORATION TECHNOLOGY TO MATERIAL RECOVERY AND REUSE

EPA Science Inventory

In an effort to aggressively remove NAPL source areas, agents such as surfactants and alcohols have been added to in situ flusing systems to enhance the solubility of the NAPL components. Such an approach has the potential to reduce the risk posed by a long term source of ground...

49 CFR 176.305 - General stowage requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., protected from sources of heat, and away from potential sources of ignition. (b) Except as otherwise... following conditions exists: (i) The bulkhead or deck is covered with at least 8 cm (3 inches) of insulation on the entire area subject to heat; (ii) A temporary wooden bulkhead at least 5 cm (2 inches) thick...

49 CFR 176.305 - General stowage requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., protected from sources of heat, and away from potential sources of ignition. (b) Except as otherwise... following conditions exists: (i) The bulkhead or deck is covered with at least 8 cm (3 inches) of insulation on the entire area subject to heat; (ii) A temporary wooden bulkhead at least 5 cm (2 inches) thick...

Characterizing sources of emissions from wildland fires

Treesearch

Roger D. Ottmar; Ana Isabel Miranda; David V. Sandberg

2009-01-01

Smoke emissions from wildland fire can be harmful to human health and welfare, impair visibility, and contribute to greenhouse gas emissions. The generation of emissions and heat release need to be characterized to estimate the potential impacts of wildland fire smoke. This requires explicit knowledge of the source, including size of the area burned, burn period,...

REMEDIATION FLUID RECYCLING: APPLICATION OF PERVAPORATION TECHNOLOGY TO MATERIAL RECOVERY AND REUSE

EPA Science Inventory

In an effort to aggressively remove NAPL source areas, agents such as surfactants and alcohols have been added to in situ flushing systems to enhance the solubility of the NAPL components. Such an approach has the potential to reduce the risk posed by a long term source of groun...

REMEDIATION FLUID RECYCLING - APPLICATION OF PERVAPORATION TECHNOLOGY TO MATERIAL RECOVERY AND REUSEI

EPA Science Inventory

In an effort to aggressively remove NAPL source areas, agents such as surfactants and alcohols have been added to in situ flusing systems to enhance the solubility of the NAPL components. Such an approach has the potential to reduce the risk posed by a long term source of ground...

Occurrence and risk assessment of potentially toxic elements and typical organic pollutants in contaminated rural soils.

PubMed

Xu, Yongfeng; Dai, Shixiang; Meng, Ke; Wang, Yuting; Ren, Wenjie; Zhao, Ling; Christie, Peter; Teng, Ying

2018-07-15

The residual levels and risk assessment of several potentially toxic elements (PTEs), phthalate esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs) in rural soils near different types of pollution sources in Tianjin, China, were studied. The soils were found to be polluted to different extents with PTEs, PAEs and PAHs from different pollution sources. The soil concentrations of chromium (Cr), nickel (Ni), di-n-butyl phthalate (DnBP), acenaphthylene (Any) and acenaphthene (Ane) were higher than their corresponding regulatory reference limits. The health risk assessment model used to calculate human exposure indicates that both non-carcinogenic and carcinogenic risks from selected pollutants were generally acceptable or close to acceptable. Different types of pollution sources and soil physicochemical properties substantially affected the soil residual concentrations of and risks from these pollutants. PTEs in soils collected from agricultural lands around industrial and residential areas and organic pollutants (PAEs and PAHs) in soils collected from agricultural areas around livestock breeding were higher than those from other types of pollution sources and merit long-term monitoring. Copyright © 2018 Elsevier B.V. All rights reserved.

Potential sources of precipitation in Lake Baikal basin

NASA Astrophysics Data System (ADS)

Shukurov, K. A.; Mokhov, I. I.

2017-11-01

Based on the data of long-term measurements at 23 meteorological stations in the Russian part of the Lake Baikal basin the probabilities of daily precipitation with different intensity and their contribution to the total precipitation are estimated. Using the trajectory model HYSPLIT_4 for each meteorological station for the period 1948-2016 the 10-day backward trajectories of air parcels, the height of these trajectories and distribution of specific humidity along the trajectories are calculated. The average field of power of potential sources of daily precipitation (less than 10 mm) for all meteorological stations in the Russian part of the Lake Baikal basin was obtained using the CWT (concentration weighted trajectory) method. The areas have been identified from which within 10 days water vapor can be transported to the Lake Baikal basin, as well as regions of the most and least powerful potential sources. The fields of the mean height of air parcels trajectories and the mean specific humidity along the trajectories are compared with the field of mean power of potential sources.

Molecular Characterization of Bacterial Populations in Sandhill Crane Feces

EPA Science Inventory

Sandhill cranes have the potential to be important seasonal sources of waterborne fecal bacteria; however, it is currently not possible to measure the extent of crane fecal pollution in potentially impacted areas as there are no available crane-specific assays. This is in part d...

Stable carbon isotopes to monitor the CO2 source mix in the urban environment

NASA Astrophysics Data System (ADS)

Vogel, F. R.; Wu, L.; Ramonet, M.; Broquet, G.; Worthy, D. E. J.

2014-12-01

Urban areas are said to be responsible for approximately 71% of fossil fuel CO2 emissions while comprising only two percent of the land area [IEA, 2008]. This limited spatial expansion could facility a monitoring of anthropogenic GHGs from atmospheric observations. As major sources of emissions, cities also have a huge potential to drive emissions reductions. To effectively manage emissions, cities must however, first establish techniques to validate their reported emission statistics. A pilot study which includes continues 13CO2 data from calibrated cavity ring-down spectrometers [Vogel et al. 2013] of two "sister sites" in the vicinity of Toronto, Canada is contrasted to recent observations of 13CO2 observations in Paris during significant pollution events. Using Miller-Tans plots [Miller and Tans, 2003] for our multi-season observations reveals significant changes of the source signatures of night time CO2 emissions which reflect the importance of natural gas burning in Megacities (up to 80% of fossil fuel sources) and show-case the potential of future isotope studies to determine source sectors. Especially the winter data this approach seems suitable to determine the source contribution of different fuel types (natural gas, liquid fuels and coal) which can inform the interpretation of other Greenhouse Gases and air pollution levels.

Search for Extended Sources in the Galactic Plane Using Six Years of Fermi-Large Area Telescope Pass 8 Data above 10 GeV

DOE PAGES

Ackermann, M.; Ajello, M.; Baldini, L.; ...

2017-07-10

The spatial extension of a γ-ray source is an essential ingredient to determine its spectral properties, as well as its potential multiwavelength counterpart. The capability to spatially resolve γ-ray sources is greatly improved by the newly delivered Fermi-Large Area Telescope (LAT) Pass 8 event-level analysis, which provides a greater acceptance and an improved point-spread function, two crucial factors for the detection of extended sources. Here, we present a complete search for extended sources located within 7° from the Galactic plane, using 6 yr of Fermi-LAT data above 10 GeV. We find 46 extended sources and provide their morphological and spectralmore » characteristics. As a result, this constitutes the first catalog of hard Fermi-LAT extended sources, named the Fermi Galactic Extended Source Catalog, which allows a thorough study of the properties of the Galactic plane in the sub-TeV domain.« less

Search for Extended Sources in the Galactic Plane Using Six Years of Fermi -Large Area Telescope Pass 8 Data above 10 GeV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ackermann, M.; Buehler, R.; Ajello, M.

The spatial extension of a γ -ray source is an essential ingredient to determine its spectral properties, as well as its potential multiwavelength counterpart. The capability to spatially resolve γ -ray sources is greatly improved by the newly delivered Fermi -Large Area Telescope (LAT) Pass 8 event-level analysis, which provides a greater acceptance and an improved point-spread function, two crucial factors for the detection of extended sources. Here, we present a complete search for extended sources located within 7° from the Galactic plane, using 6 yr of Fermi -LAT data above 10 GeV. We find 46 extended sources and providemore » their morphological and spectral characteristics. This constitutes the first catalog of hard Fermi -LAT extended sources, named the Fermi Galactic Extended Source Catalog, which allows a thorough study of the properties of the Galactic plane in the sub-TeV domain.« less

Search for Extended Sources in the Galactic Plane Using Six Years of Fermi-Large Area Telescope Pass 8 Data above 10 GeV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ackermann, M.; Ajello, M.; Baldini, L.

The spatial extension of a γ-ray source is an essential ingredient to determine its spectral properties, as well as its potential multiwavelength counterpart. The capability to spatially resolve γ-ray sources is greatly improved by the newly delivered Fermi-Large Area Telescope (LAT) Pass 8 event-level analysis, which provides a greater acceptance and an improved point-spread function, two crucial factors for the detection of extended sources. Here, we present a complete search for extended sources located within 7° from the Galactic plane, using 6 yr of Fermi-LAT data above 10 GeV. We find 46 extended sources and provide their morphological and spectralmore » characteristics. As a result, this constitutes the first catalog of hard Fermi-LAT extended sources, named the Fermi Galactic Extended Source Catalog, which allows a thorough study of the properties of the Galactic plane in the sub-TeV domain.« less

Search for Extended Sources in the Galactic Plane Using Six Years of Fermi-Large Area Telescope Pass 8 Data above 10 GeV

NASA Astrophysics Data System (ADS)

Ackermann, M.; Ajello, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Bissaldi, E.; Bloom, E. D.; Bonino, R.; Bottacini, E.; Brandt, T. J.; Bregeon, J.; Bruel, P.; Buehler, R.; Cameron, R. A.; Caragiulo, M.; Caraveo, P. A.; Castro, D.; Cavazzuti, E.; Cecchi, C.; Charles, E.; Chekhtman, A.; Cheung, C. C.; Chiaro, G.; Ciprini, S.; Cohen, J. M.; Costantin, D.; Costanza, F.; Cutini, S.; D'Ammando, F.; de Palma, F.; Desiante, R.; Digel, S. W.; Di Lalla, N.; Di Mauro, M.; Di Venere, L.; Favuzzi, C.; Fegan, S. J.; Ferrara, E. C.; Franckowiak, A.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Giordano, F.; Giroletti, M.; Green, D.; Grenier, I. A.; Grondin, M.-H.; Guillemot, L.; Guiriec, S.; Harding, A. K.; Hays, E.; Hewitt, J. W.; Horan, D.; Hou, X.; Jóhannesson, G.; Kamae, T.; Kuss, M.; La Mura, G.; Larsson, S.; Lemoine-Goumard, M.; Li, J.; Longo, F.; Loparco, F.; Lubrano, P.; Magill, J. D.; Maldera, S.; Malyshev, D.; Manfreda, A.; Mazziotta, M. N.; Michelson, P. F.; Mitthumsiri, W.; Mizuno, T.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Negro, M.; Nuss, E.; Ohsugi, T.; Omodei, N.; Orienti, M.; Orlando, E.; Ormes, J. F.; Paliya, V. S.; Paneque, D.; Perkins, J. S.; Persic, M.; Pesce-Rollins, M.; Petrosian, V.; Piron, F.; Porter, T. A.; Principe, G.; Rainò, S.; Rando, R.; Razzano, M.; Razzaque, S.; Reimer, A.; Reimer, O.; Reposeur, T.; Sgrò, C.; Simone, D.; Siskind, E. J.; Spada, F.; Spandre, G.; Spinelli, P.; Suson, D. J.; Tak, D.; Thayer, J. B.; Thompson, D. J.; Torres, D. F.; Tosti, G.; Troja, E.; Vianello, G.; Wood, K. S.; Wood, M.

2017-07-01

The spatial extension of a γ-ray source is an essential ingredient to determine its spectral properties, as well as its potential multiwavelength counterpart. The capability to spatially resolve γ-ray sources is greatly improved by the newly delivered Fermi-Large Area Telescope (LAT) Pass 8 event-level analysis, which provides a greater acceptance and an improved point-spread function, two crucial factors for the detection of extended sources. Here, we present a complete search for extended sources located within 7° from the Galactic plane, using 6 yr of Fermi-LAT data above 10 GeV. We find 46 extended sources and provide their morphological and spectral characteristics. This constitutes the first catalog of hard Fermi-LAT extended sources, named the Fermi Galactic Extended Source Catalog, which allows a thorough study of the properties of the Galactic plane in the sub-TeV domain.

Trace elements of concern affecting urban agriculture in industrialized areas: A multivariate approach.

PubMed

Boente, C; Matanzas, N; García-González, N; Rodríguez-Valdés, E; Gallego, J R

2017-09-01

The urban and peri-urban soils used for agriculture could be contaminated by atmospheric deposition or industrial releases, thus raising concerns about the potential risk to public health. Here we propose a method to evaluate potential soil pollution based on multivariate statistics, geostatistics (kriging), a novel soil pollution index, and bioavailability assessments. This approach was tested in two districts of a highly populated and industrialized city (Gijón, Spain). The soils showed anomalous content of several trace elements, such as As and Pb (up to 80 and 585 mg kg -1 respectively). In addition, factor analyses associated these elements with anthropogenic activity, whereas other elements were attributed to natural sources. Subsequent clustering also facilitated the differentiation between the northern area studied (only limited Pb pollution found) and the southern area (pattern of coal combustion, including simultaneous anomalies of trace elements and benzo(a)pyrene). A normalized soil pollution index (SPI) was calculated by kriging, using only the elements falling above threshold levels; therefore point-source polluted zones in the northern area and diffuse contamination in the south were identified. In addition, in the six mapping units with the highest SPIs of the fifty studied, we observed low bioavailability for most of the elements that surpassed the threshold levels. However, some anomalies of Pb contents and the pollution fingerprint in the central area of the southern grid call for further site-specific studies. On the whole, the combination of a multivariate (geo) statistic approach and a bioavailability assessment allowed us to efficiently identify sources of contamination and potential risks. Copyright © 2017 Elsevier Ltd. All rights reserved.

Shale characterization in mass transport complex as a potential source rock: An example from onshore West Java Basin, Indonesia

NASA Astrophysics Data System (ADS)

Nugraha, A. M. S.; Widiarti, R.; Kusumah, E. P.

2017-12-01

This study describes a deep-water slump facies shale of the Early Miocene Jatiluhur/Cibulakan Formation to understand its potential as a source rock in an active tectonic region, the onshore West Java. The formation is equivalent with the Gumai Formation, which has been well-known as another prolific source rock besides the Oligocene Talang Akar Formation in North West Java Basin, Indonesia. The equivalent shale formation is expected to have same potential source rock towards the onshore of Central Java. The shale samples were taken onshore, 150 km away from the basin. The shale must be rich of organic matter, have good quality of kerogen, and thermally matured to be categorized as a potential source rock. Investigations from petrography, X-Ray diffractions (XRD), and backscattered electron show heterogeneous mineralogy in the shales. The mineralogy consists of clay minerals, minor quartz, muscovite, calcite, chlorite, clinopyroxene, and other weathered minerals. This composition makes the shale more brittle. Scanning Electron Microscope (SEM) analysis indicate secondary porosities and microstructures. Total Organic Carbon (TOC) shows 0.8-1.1 wt%, compared to the basinal shale 1.5-8 wt%. The shale properties from this outcropped formation indicate a good potential source rock that can be found in the subsurface area with better quality and maturity.

Using a topographic index to distribute variable source area runoff predicted with the SCS curve-number equation

NASA Astrophysics Data System (ADS)

Lyon, Steve W.; Walter, M. Todd; Gérard-Marchant, Pierre; Steenhuis, Tammo S.

2004-10-01

Because the traditional Soil Conservation Service curve-number (SCS-CN) approach continues to be used ubiquitously in water quality models, new application methods are needed that are consistent with variable source area (VSA) hydrological processes in the landscape. We developed and tested a distributed approach for applying the traditional SCS-CN equation to watersheds where VSA hydrology is a dominant process. Predicting the location of source areas is important for watershed planning because restricting potentially polluting activities from runoff source areas is fundamental to controlling non-point-source pollution. The method presented here used the traditional SCS-CN approach to predict runoff volume and spatial extent of saturated areas and a topographic index, like that used in TOPMODEL, to distribute runoff source areas through watersheds. The resulting distributed CN-VSA method was applied to two subwatersheds of the Delaware basin in the Catskill Mountains region of New York State and one watershed in south-eastern Australia to produce runoff-probability maps. Observed saturated area locations in the watersheds agreed with the distributed CN-VSA method. Results showed good agreement with those obtained from the previously validated soil moisture routing (SMR) model. When compared with the traditional SCS-CN method, the distributed CN-VSA method predicted a similar total volume of runoff, but vastly different locations of runoff generation. Thus, the distributed CN-VSA approach provides a physically based method that is simple enough to be incorporated into water quality models, and other tools that currently use the traditional SCS-CN method, while still adhering to the principles of VSA hydrology.

Detecting black bear source-sink dynamics using individual-based genetic graphs.

PubMed

Draheim, Hope M; Moore, Jennifer A; Etter, Dwayne; Winterstein, Scott R; Scribner, Kim T

2016-07-27

Source-sink dynamics affects population connectivity, spatial genetic structure and population viability for many species. We introduce a novel approach that uses individual-based genetic graphs to identify source-sink areas within a continuously distributed population of black bears (Ursus americanus) in the northern lower peninsula (NLP) of Michigan, USA. Black bear harvest samples (n = 569, from 2002, 2006 and 2010) were genotyped at 12 microsatellite loci and locations were compared across years to identify areas of consistent occupancy over time. We compared graph metrics estimated for a genetic model with metrics from 10 ecological models to identify ecological factors that were associated with sources and sinks. We identified 62 source nodes, 16 of which represent important source areas (net flux > 0.7) and 79 sink nodes. Source strength was significantly correlated with bear local harvest density (a proxy for bear density) and habitat suitability. Additionally, resampling simulations showed our approach is robust to potential sampling bias from uneven sample dispersion. Findings demonstrate black bears in the NLP exhibit asymmetric gene flow, and individual-based genetic graphs can characterize source-sink dynamics in continuously distributed species in the absence of discrete habitat patches. Our findings warrant consideration of undetected source-sink dynamics and their implications on harvest management of game species. © 2016 The Author(s).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Werth, David; Buckley, Robert

Here, the detectability of emission sources, defined by a low-level of mixing with other sources, was estimated for various locations surrounding the Sea of Japan, including a site within North Korea. A high-resolution meteorological model coupled to a dispersion model was used to simulate plume dynamics for four periods, and two metrics of airborne plume mixing were calculated for each source. While emissions from several known sources in this area tended to blend with others while dispersing downwind, the North Korean plume often remained relatively distinct, thereby making it potentially easier to unambiguously ‘backtrack’ it to its source.

The mineral resource potential of the Thaniyah and Al Ufayriyah quadrangles, sheets 20/42 C and 20/42 A, Kingdom of Saudi Arabia

USGS Publications Warehouse

Fenton, Michael D.

1983-01-01

Areas with mineral resource potential in the Thaniyah and Al Ufayriyah quadrangles in the central Precambrian Shield of Saudi Arabia have been identified by reconnaissance rock geochemistry and inspection of ancient prospects. Locally anomalous areas in plutonic terrane have been defined as possible sources of tin, molybdenum, or base metal mineralization. The survey over layered volcanic terrane identified several areas of anomalous copper and zinc. One ancient copper prospect with gossan in the west-central part of the Thaniyah quadrangle merits additional study.

Carbon footprint of urban source separation for nutrient recovery.

PubMed

Kjerstadius, H; Bernstad Saraiva, A; Spångberg, J; Davidsson, Å

2017-07-15

Source separation systems for the management of domestic wastewater and food waste has been suggested as more sustainable sanitation systems for urban areas. The present study used an attributional life cycle assessment to investigate the carbon footprint and potential for nutrient recovery of two sanitation systems for a hypothetical urban area in Southern Sweden. The systems represented a typical Swedish conventional system and a possible source separation system with increased nutrient recovery. The assessment included the management chain from household collection, transport, treatment and final return of nutrients to agriculture or disposal of the residuals. The results for carbon footprint and nutrient recovery (phosphorus and nitrogen) concluded that the source separation system could increase nutrient recovery (0.30-0.38 kg P capita -1 year -1 and 3.10-3.28 kg N capita -1 year -1 ), while decreasing the carbon footprint (-24 to -58 kg CO 2 -eq. capita -1 year -1 ), compared to the conventional system. The nutrient recovery was increased by the use of struvite precipitation and ammonium stripping at the wastewater treatment plant. The carbon footprint decreased, mainly due to the increased biogas production, increased replacement of mineral fertilizer in agriculture and less emissions of nitrous oxide from wastewater treatment. In conclusion, the study showed that source separation systems could potentially be used to increase nutrient recovery from urban areas, while decreasing the climate impact. Copyright © 2017 Elsevier Ltd. All rights reserved.

An Integrated Risk Management Model for Source Water Protection Areas

PubMed Central

Chiueh, Pei-Te; Shang, Wei-Ting; Lo, Shang-Lien

2012-01-01

Watersheds are recognized as the most effective management unit for the protection of water resources. For surface water supplies that use water from upstream watersheds, evaluating threats to water quality and implementing a watershed management plan are crucial for the maintenance of drinking water safe for humans. The aim of this article is to establish a risk assessment model that provides basic information for identifying critical pollutants and areas at high risk for degraded water quality. In this study, a quantitative risk model that uses hazard quotients for each water quality parameter was combined with a qualitative risk model that uses the relative risk level of potential pollution events in order to characterize the current condition and potential risk of watersheds providing drinking water. In a case study of Taipei Source Water Area in northern Taiwan, total coliforms and total phosphorus were the top two pollutants of concern. Intensive tea-growing and recreational activities around the riparian zone may contribute the greatest pollution to the watershed. Our risk assessment tool may be enhanced by developing, recording, and updating information on pollution sources in the water supply watersheds. Moreover, management authorities could use the resultant information to create watershed risk management plans. PMID:23202770

Persistence of DNA in carcasses, slime and avian feces may affect interpretation of environmental DNA data

USGS Publications Warehouse

Merkes, Christopher M.; McCalla, S. Grace; Jensen, Nathan R.; Gaikowski, Mark P.; Amberg, Jon J.

2014-01-01

The prevention of non-indigenous aquatic invasive species spreading into new areas is a goal of many resource managers. New techniques have been developed to survey for species that are difficult to capture with conventional gears that involve the detection of their DNA in water samples (eDNA). This technique is currently used to track the invasion of bigheaded carps (silver carp and bighead carp; Hypophthalmichthys molitrix and H. nobilis) in the Chicago Area Waterway System and Upper Mississippi River. In both systems DNA has been detected from silver carp without the capture of a live fish, which has led to some uncertainty about the source of the DNA. The potential contribution to eDNA by vectors and fomites has not been explored. Because barges move from areas with a high abundance of bigheaded carps to areas monitored for the potential presence of silver carp, we used juvenile silver carp to simulate the barge transport of dead bigheaded carp carcasses, slime residue, and predator feces to determine the potential of these sources to supply DNA to uninhabited waters where it could be detected and misinterpreted as indicative of the presence of live bigheaded carp. Our results indicate that all three vectors are feasible sources of detectable eDNA for at least one month after their deposition. This suggests that current monitoring programs must consider alternative vectors of DNA in the environment and consider alternative strategies to minimize the detection of DNA not directly released from live bigheaded carps.

Persistence of DNA in Carcasses, Slime and Avian Feces May Affect Interpretation of Environmental DNA Data

PubMed Central

Merkes, Christopher M.; McCalla, S. Grace; Jensen, Nathan R.; Gaikowski, Mark P.; Amberg, Jon J.

2014-01-01

The prevention of non-indigenous aquatic invasive species spreading into new areas is a goal of many resource managers. New techniques have been developed to survey for species that are difficult to capture with conventional gears that involve the detection of their DNA in water samples (eDNA). This technique is currently used to track the invasion of bigheaded carps (silver carp and bighead carp; Hypophthalmichthys molitrix and H. nobilis) in the Chicago Area Waterway System and Upper Mississippi River. In both systems DNA has been detected from silver carp without the capture of a live fish, which has led to some uncertainty about the source of the DNA. The potential contribution to eDNA by vectors and fomites has not been explored. Because barges move from areas with a high abundance of bigheaded carps to areas monitored for the potential presence of silver carp, we used juvenile silver carp to simulate the barge transport of dead bigheaded carp carcasses, slime residue, and predator feces to determine the potential of these sources to supply DNA to uninhabited waters where it could be detected and misinterpreted as indicative of the presence of live bigheaded carp. Our results indicate that all three vectors are feasible sources of detectable eDNA for at least one month after their deposition. This suggests that current monitoring programs must consider alternative vectors of DNA in the environment and consider alternative strategies to minimize the detection of DNA not directly released from live bigheaded carps. PMID:25402206

Persistence of DNA in carcasses, slime and avian feces may affect interpretation of environmental DNA data.

PubMed

Merkes, Christopher M; McCalla, S Grace; Jensen, Nathan R; Gaikowski, Mark P; Amberg, Jon J

2014-01-01

The prevention of non-indigenous aquatic invasive species spreading into new areas is a goal of many resource managers. New techniques have been developed to survey for species that are difficult to capture with conventional gears that involve the detection of their DNA in water samples (eDNA). This technique is currently used to track the invasion of bigheaded carps (silver carp and bighead carp; Hypophthalmichthys molitrix and H. nobilis) in the Chicago Area Waterway System and Upper Mississippi River. In both systems DNA has been detected from silver carp without the capture of a live fish, which has led to some uncertainty about the source of the DNA. The potential contribution to eDNA by vectors and fomites has not been explored. Because barges move from areas with a high abundance of bigheaded carps to areas monitored for the potential presence of silver carp, we used juvenile silver carp to simulate the barge transport of dead bigheaded carp carcasses, slime residue, and predator feces to determine the potential of these sources to supply DNA to uninhabited waters where it could be detected and misinterpreted as indicative of the presence of live bigheaded carp. Our results indicate that all three vectors are feasible sources of detectable eDNA for at least one month after their deposition. This suggests that current monitoring programs must consider alternative vectors of DNA in the environment and consider alternative strategies to minimize the detection of DNA not directly released from live bigheaded carps.

Estimation of source locations of total gaseous mercury measured in New York State using trajectory-based models

NASA Astrophysics Data System (ADS)

Han, Young-Ji; Holsen, Thomas M.; Hopke, Philip K.

Ambient gaseous phase mercury concentrations (TGM) were measured at three locations in NY State including Potsdam, Stockton, and Sterling from May 2000 to March 2005. Using these data, three hybrid receptor models incorporating backward trajectories were used to identify source areas for TGM. The models used were potential source contribution function (PSCF), residence time weighted concentration (RTWC), and simplified quantitative transport bias analysis (SQTBA). Each model was applied using multi-site measurements to resolve the locations of important mercury sources for New York State. PSCF results showed that southeastern New York, Ohio, Indiana, Tennessee, Louisiana, and Virginia were important TGM source areas for these sites. RTWC identified Canadian sources including the metal production facilities in Ontario and Quebec, but US regional sources including the Ohio River Valley were also resolved. Sources in southeastern NY, Massachusetts, western Pennsylvania, Indiana, and northern Illinois were identified to be significant by SQTBA. The three modeling results were combined to locate the most important probable source locations, and those are Ohio, Indiana, Illinois, and Wisconsin. The Atlantic Ocean was suggested to be a possible source as well.

Geographical limits to species-range shifts are suggested by climate velocity.

PubMed

Burrows, Michael T; Schoeman, David S; Richardson, Anthony J; Molinos, Jorge García; Hoffmann, Ary; Buckley, Lauren B; Moore, Pippa J; Brown, Christopher J; Bruno, John F; Duarte, Carlos M; Halpern, Benjamin S; Hoegh-Guldberg, Ove; Kappel, Carrie V; Kiessling, Wolfgang; O'Connor, Mary I; Pandolfi, John M; Parmesan, Camille; Sydeman, William J; Ferrier, Simon; Williams, Kristen J; Poloczanska, Elvira S

2014-03-27

The reorganization of patterns of species diversity driven by anthropogenic climate change, and the consequences for humans, are not yet fully understood or appreciated. Nevertheless, changes in climate conditions are useful for predicting shifts in species distributions at global and local scales. Here we use the velocity of climate change to derive spatial trajectories for climatic niches from 1960 to 2009 (ref. 7) and from 2006 to 2100, and use the properties of these trajectories to infer changes in species distributions. Coastlines act as barriers and locally cooler areas act as attractors for trajectories, creating source and sink areas for local climatic conditions. Climate source areas indicate where locally novel conditions are not connected to areas where similar climates previously occurred, and are thereby inaccessible to climate migrants tracking isotherms: 16% of global surface area for 1960 to 2009, and 34% of ocean for the 'business as usual' climate scenario (representative concentration pathway (RCP) 8.5) representing continued use of fossil fuels without mitigation. Climate sink areas are where climate conditions locally disappear, potentially blocking the movement of climate migrants. Sink areas comprise 1.0% of ocean area and 3.6% of land and are prevalent on coasts and high ground. Using this approach to infer shifts in species distributions gives global and regional maps of the expected direction and rate of shifts of climate migrants, and suggests areas of potential loss of species richness.

Hydrocarbon source rock potential of the Karoo in Zimbabwe

NASA Astrophysics Data System (ADS)

Hiller, K.; Shoko, U.

1996-07-01

The hydrocarbon potential of Zimbabwe is tied to the Karoo rifts which fringe the Zimbabwe Craton, i.e. the Mid-Zambezi basin/rift and the Mana Pools basin in the northwest, the Cabora Bassa basin in the north and the Tuli-Bubye and Sabi-Runde basins in the south. Based on the geochemical investigation of almost one thousand samples of fine clastic Karoo sediments, a concise source rock inventory has been established showing the following features. No marine source rocks have been identified. In the Mid-Zambezi area and Cabora Bassa basin, the source rocks are gas-prone, carbonaceous to coaly mudstones and coal of Lower Karoo age. In the Cabora Bassa basin, similar gas-prone source rocks occur in the Upper Karoo (Angwa Alternations Member). These kerogen type III source rocks are widespread and predominantly immature to moderately mature. In the southern basins, the Lower Karoo source rocks are gas-prone; in addition some have a small condensate potential. Most of the samples are, however, overmature due to numerous dolerite intrusions. Samples with a mixed gas, condensate and oil potential (mainly kerogen types II and III) were identified in the Lower Karoo (Coal Measure and Lower Madumabisa Mudstone Formations) of the Mid-Zambezi basin, and in the Louver Karoo (Mkanga Formation) and Upper Karoo (Upper Angwa Alternations Member Formation) of the Cabora Bassa basin. The source rocks, with a liquid potential, are also immature to moderately mature and were deposited in swamp, paludal and lacustrine environments of limited extent.

Source rock potential in Pakistan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raza, H.A.

1991-03-01

Pakistan contains two sedimentary basins: Indus in the east and Balochistan in the west. The Indus basin has received sediments from precambrian until Recent, albeit with breaks. It has been producing hydrocarbons since 1914 from three main producing regions, namely, the Potwar, Sulaisman, and Kirthar. In the Potwar, oil has been discovered in Cambrian, Permian, Jurassic, and Tertiary rocks. Potential source rocks are identified in Infra-Cambrian, Permian, Paleocene, and Eocene successions, but Paleocene/Eocene Patala Formation seems to be the main source of most of the oil. In the Sulaiman, gas has been found in Cretaceous and Tertiary; condensate in Cretaceousmore » rocks. Potential source rocks are indicated in Cretaceous, Paleocene, and Eocene successions. The Sembar Formation of Early Cretaceous age appears to be the source of gas. In the Kirthar, oil and gas have been discovered in Cretaceous and gas has been discovered in paleocene and Eocene rocks. Potential source rocks are identified in Kirthar and Ghazij formations of Eocene age in the western part. However, in the easter oil- and gas-producing Badin platform area, Union Texas has recognized the Sembar Formation of Early Cretaceous age as the only source of Cretaceous oil and gas. The Balochistan basin is part of an Early Tertiary arc-trench system. The basin is inadequately explored, and there is no oil or gas discovery so far. However, potential source rocks have been identified in Eocene, Oligocene, Miocene, and Pliocene successions based on geochemical analysis of surface samples. Mud volcanoes are present.« less

Source water assessment and nonpoint sources of acutely toxic contaminants: A review of research related to survival and transport of Cryptosporidium parvum

NASA Astrophysics Data System (ADS)

Walker, Mark J.; Montemagno, Carlo D.; Jenkins, Michael B.

1998-12-01

Amendments to the Safe Drinking Water Act (PL-930123) in 1996 required that public water supply managers identify potential sources of contamination within contributing areas. Nonpoint sources of acutely toxic microbial contaminants, such as Cryptosporidium parvum, challenge current approaches to source identification and management as a first step toward developing management plans for public water supply protection. Little may be known about survival and transport in the field environment, prescribed practices may not be designed to manage such substances, and infective stages may be present in vast numbers and may resist water treatment and disinfection processes. This review summarizes research related to survival and transport of C. parvum oocysts, as an example of an acutely toxic contaminant with nonpoint sources in animal agriculture. It discusses ∥1) significance of infected domesticated animals as potential sources of C. parvum, (2) laboratory and field studies of survival and transport, and (3) approaches to source control in the context of public health protection.

Occurrence, Distribution, Sources, and Trends of Elevated Chloride Concentrations in the Mississippi River Valley Alluvial Aquifer in Southeastern Arkansas

USGS Publications Warehouse

Kresse, Timothy M.; Clark, Brian R.

2008-01-01

Water-quality data from approximately 2,500 sites were used to investigate the distribution of chloride concentrations in the Mississippi River Valley alluvial aquifer in southeastern Arkansas. The large volume and areal distribution of the data used for the investigation proved useful in delineating areas of elevated (greater than 100 milligrams per liter) chloride concentrations, assessing potential sources of saline water, and evaluating trends in chloride distribution and concentration over time. Irrigation water containing elevated chloride concentrations is associated with negative effects to rice and soybeans, two of the major crops in Arkansas, and a groundwater chloride concentration of 100 milligrams per liter is recommended as the upper limit for use on rice. As such, accurately delineating areas with high salinity ground water, defining potential sources of chloride, and documenting trends over time is important in assisting the agricultural community in water management. The distribution and range of chloride concentrations in the study area revealed distinct areas of elevated chloride concentrations. Area I includes an elongated, generally northwest-southeast trending band of moderately elevated chloride concentrations in the northern part of the study area. This band of elevated chloride concentrations is approximately 40 miles in length and varies from approximately 2 to 9 miles in width, with a maximum chloride concentration of 360 milligrams per liter. Area II is a narrow, north-south trending band of elevated chloride concentrations in the southern part of the study area, with a maximum chloride concentration of 1,639 milligrams per liter. A zone of chloride concentrations exceeding 200 milligrams per liter is approximately 25 miles in length and 5 to 6 miles in width. In Area I, low chloride concentrations in samples from wells completed in the alluvial aquifer next to the Arkansas River and in samples from the upper Claiborne aquifer, which underlies the alluvial aquifer, indicate that leakage from the river and upward flow of saline water in underlying aquifers are not likely sources for the saline water in the alluvial aquifer in Area I. A good comparison was noted for chloride concentrations in Area I and surface geomorphology. In the majority of cases, elevated chloride concentrations occurred in backswamp deposits, with low concentrations (less than 50 milligrams per liter) in areas of active or abandoned channel deposits. The fine-grained, clay-rich deposits associated with backswamp areas likely restrict recharge, induce increased ratios between evapotranspiration and recharge, and experience minimal flushing of salts concentrated during evapotranspiration. In Area II, chloride isoconcentration maps of the underlying upper Claiborne aquifer, in addition to samples from wells completed in the middle and lower Claiborne aquifers, showed a similar chloride distribution to that of the alluvial aquifer with decreasing chloride concentrations to the east of the zone of elevated chloride concentrations, which suggests a deeper source of saline water that affects Tertiary and Quaternary aquifer systems. Mixing curves developed from bromide/chloride ratios in water samples from the alluvial aquifer, Tertiary aquifers, and samples of brine water from the Jurrasic Smackover Formation additionally discounted upward flow of saline water from underlying Tertiary formations as a potential mechanism for salinity in the alluvial aquifer in Area II. A review of information on oil exploration wells in Chicot County revealed that most of these wells were drilled from 1960 to 1980, after the elevated chloride concentrations were detected in the early 1950s. The elongated nature of the zone of elevated chloride concentrations in Area II suggests a line source or linear conduit connection with the source. Maps of a fractured limestone in the Smackover Formation in Arkansas, Mississippi, and Louisiana for purpose

Biomonitoring of PAHs by using Quercus ilex leaves: Source diagnostic and toxicity assessment

NASA Astrophysics Data System (ADS)

De Nicola, Flavia; Claudia, Lancellotti; MariaVittoria, Prati; Giulia, Maisto; Anna, Alfani

2011-03-01

Quercus ilex L. leaves were sampled at nineteen urban sites and two remote sites in order to evaluate PAH contamination degree. One-, two- and three-year-old leaves were collected and leaf lipid content was measured to investigate the influence of leaf age and lipids in PAH accumulation. Some PAH diagnostic ratios, such as Ant/Ant + Phen, Flt/Flt + Pyr, B[a]A/B[a]A + Crys and IP/IP + B[g,h,i]P, were calculated. The results suggest that Q. ilex leaves are effective biomonitors of PAH air contamination: in fact, a great PAH accumulation in leaves from the urban areas, until 30-time higher compared to those from the remote sites, has been observed. At each site, the similar total PAH concentrations in leaves of different age, probably due to a canopy effect, indicate an ability of all leaf age classes to monitor local PAH concentrations in air, remarking practical implications for air biomonitoring. The findings suggest that PAH adsorption in Q. ilex leaves does not result limited by leaf lipid content. Moreover, this study demonstrates the source-diagnostic potential of Q. ilex leaves, because, in particular, the Flt/Flt + Pyr and IP/IP + B[g,h,i]P ratios indicate vehicular traffic as the main source of PAHs in the urban areas and wood combustion in the remote areas. Moreover, to distinguish biomass combustion source, a promising tracer PAH as DB[a,h]A could be used. The high contribution of DB[a,h]A to total PAH concentrations at the remote sites determines a high carcinogenic potential in this area, similar to that calculated for the urban area where the carcinogenic PAH concentrations in absolute values are often higher.

Remote-sensing-based analysis of landscape change in the desiccated seabed of the Aral Sea--a potential tool for assessing the hazard degree of dust and salt storms.

PubMed

Löw, F; Navratil, P; Kotte, K; Schöler, H F; Bubenzer, O

2013-10-01

With the recession of the Aral Sea in Central Asia, once the world's fourth largest lake, a huge new saline desert emerged which is nowadays called the Aralkum. Saline soils in the Aralkum are a major source for dust and salt storms in the region. The aim of this study was to analyze the spatio-temporal land cover change dynamics in the Aralkum and discuss potential implications for the recent and future dust and salt storm activity in the region. MODIS satellite time series were classified from 2000-2008 and change of land cover was quantified. The Aral Sea desiccation accelerated between 2004 and 2008. The area of sandy surfaces and salt soils, which bear the greatest dust and salt storm generation potential increased by more than 36 %. In parts of the Aralkum desalinization of soils was found to take place within 4-8 years. The implication of the ongoing regression of the Aral Sea is that the expansion of saline surfaces will continue. Knowing the spatio-temporal dynamics of both the location and the surface characteristics of the source areas for dust and salt storms allows drawing conclusions about the potential hazard degree of the dust load. The remote-sensing-based land cover assessment presented in this study could be coupled with existing knowledge on the location of source areas for an early estimation of trends in shifting dust composition. Opportunities, limits, and requirements of satellite-based land cover classification and change detection in the Aralkum are discussed.

A Modeling System to Examine Near-Road and Near-Source Air Toxics for Community-Scale Cumulative Assessments.

EPA Science Inventory

Cumulative assessments consider a range of potential stressors that might impact the health of a receptor, such as a local neighborhood or wetland area. When receptors are located near pollution sources such as highways or ports (within 500-1,000 m), then they could be at risk of...

Applications of satellite-derived disturbance information in support of sustainable forest management

Treesearch

Sean Healey; Warren Cohen; Gretchen Moisen

2007-01-01

The need for current information about the effects of fires, harvest, and storms is evident in many areas of sustainable forest management. While there are several potential sources of this information, each source has its limitations. Generally speaking, the statistical rigor associated with traditional forest sampling is an important asset in any monitoring effort....

Estimating and validating surface energy fluxes at field scale over a heterogeneous land surfaces based on two-source energy balance model (TSEB)

USDA-ARS?s Scientific Manuscript database

Accurate estimation of surface energy fluxes at field scale over large areas has the potential to improve agricultural water management in arid and semiarid watersheds. Remote sensing may be the only viable approach for mapping fluxes over heterogeneous landscapes. The Two-Source Energy Balance mode...

Managing grazing of riparian areas in the Intermountain Region

Treesearch

Warren P. Clary; Bert F. Webster

1989-01-01

Concern about livestock grazing in riparian habitats and its effect upon riparian-dependent resources has resulted in numerous controversies about the appropriate management approach. This document provides guidance for grazing of riparian areas in a manner that should reduce both nonpoint source pollution and potential grazing impacts on other riparian-dependent...

Geochemical evidence for diversity of dust sources in the southwestern United States

USGS Publications Warehouse

Reheis, M.C.; Budahn, J.R.; Lamothe, P.J.

2002-01-01

Several potential dust sources, including generic sources of sparsely vegetated alluvium, playa deposits, and anthropogenic emissions, as well as the area around Owens Lake, California, affect the composition of modern dust in the southwestern United States. A comparison of geochemical analyses of modern and old (a few thousand years) dust with samples of potential local sources suggests that dusts reflect four primary sources: (1) alluvial sediments (represented by Hf, K, Rb, Zr, and rare-earth elements, (2) playas, most of which produce calcareous dust (Sr, associated with Ca), (3) the area of Owens (dry) Lake, a human-induced playa (As, Ba, Li, Pb, Sb, and Sr), and (4) anthropogenic and/or volcanic emissions (As, Cr, Ni, and Sb). A comparison of dust and source samples with previous analyses shows that Owens (dry) Lake and mining wastes from the adjacent Cerro Gordo mining district are the primary sources of As, Ba, Li, and Pb in dusts from Owens Valley. Decreases in dust contents of As, Ba, and Sb with distance from Owens Valley suggest that dust from southern Owens Valley is being transported at least 400 km to the east. Samples of old dust that accumulated before European settlement are distinctly lower in As, Ba, and Sb abundances relative to modern dust, likely due to modern transport of dust from Owens Valley. Thus, southern Owens Valley appears to be an important, geochemically distinct, point source for regional dust in the southwestern United States. Copyright ?? 2002 Elsevier Science Ltd.

GIS prospectivity mapping and 3D modeling validation for potential uranium deposit targets in Shangnan district, China

NASA Astrophysics Data System (ADS)

Xie, Jiayu; Wang, Gongwen; Sha, Yazhou; Liu, Jiajun; Wen, Botao; Nie, Ming; Zhang, Shuai

2017-04-01

Integrating multi-source geoscience information (such as geology, geophysics, geochemistry, and remote sensing) using GIS mapping is one of the key topics and frontiers in quantitative geosciences for mineral exploration. GIS prospective mapping and three-dimensional (3D) modeling can be used not only to extract exploration criteria and delineate metallogenetic targets but also to provide important information for the quantitative assessment of mineral resources. This paper uses the Shangnan district of Shaanxi province (China) as a case study area. GIS mapping and potential granite-hydrothermal uranium targeting were conducted in the study area combining weights of evidence (WofE) and concentration-area (C-A) fractal methods with multi-source geoscience information. 3D deposit-scale modeling using GOCAD software was performed to validate the shapes and features of the potential targets at the subsurface. The research results show that: (1) the known deposits have potential zones at depth, and the 3D geological models can delineate surface or subsurface ore-forming features, which can be used to analyze the uncertainty of the shape and feature of prospectivity mapping at the subsurface; (2) single geochemistry anomalies or remote sensing anomalies at the surface require combining the depth exploration criteria of geophysics to identify potential targets; and (3) the single or sparse exploration criteria zone with few mineralization spots at the surface has high uncertainty in terms of the exploration target.

[Spatial Distribution and Potential Ecological Risk Assessment of Heavy Metals in Soils and Sediments in Shunde Waterway, Southern China].

PubMed

Cai, Yi-min; Chen, Wei-ping; Peng, Chi; Wang, Tie-yu; Xiao, Rong-bo

2016-05-15

Environmental quality of soils and sediments around water source area can influence the safety of potable water of rivers. In order to study the pollution characteristics, the sources and ecological risks of heavy metals Zn, Cr, Pb, Cu, Ni and Cd in water source area, surface soils around the waterway and sediments in the estuary of main tributaries were collected in Shunde, and ecological risks of heavy metals were assessed by two methods of potential ecological risk assessment. The mean contents of Zn, Cr, Pb, Cu, Ni and Cd in the surface soils were 186.80, 65.88, 54.56, 32.47, 22.65 and 0.86 mg · kg⁻¹ respectively, and they were higher than their soil background values except those of Cu and Ni. The mean concentrations of Zn, Cr, Pb, Cu, Ni and Cd in the sediments were 312.11, 111.41, 97.87, 92.32, 29.89 and 1.72 mg · kg⁻¹ respectively, and they were higher than their soil background values except that of Ni. The results of principal component analysis illustrated that the main source of Cr and Ni in soils was soil parent materials, and Zn, Pb, Cu and Cd in soils mainly came from wastewater discharge of local manufacturing industry. The six heavy metals in sediments mainly originated from industry emissions around the Shunde waterway. The results of potential ecological risk assessment integrating environmental bioavailability of heavy metals showed that Zn, Cu, Pb and Ni had a slight potential ecological risk. Cd had a slight potential ecological risk in surface soils, but a moderate potential ecological risk in surfaces sediments. Because the potential ecological risk assessment integrating environmental bioavailability of heavy metals took the soil properties and heavy metal forms into account, its results of risks were lower than those of Hakanson methods, and it could avoid overestimating the potential risks of heavy metals.

Evaluation of light detector surface area for functional Near Infrared Spectroscopy.

PubMed

Wang, Lei; Ayaz, Hasan; Izzetoglu, Meltem; Onaral, Banu

2017-10-01

Functional Near Infrared Spectroscopy (fNIRS) is an emerging neuroimaging technique that utilizes near infrared light to detect cortical concentration changes of oxy-hemoglobin and deoxy-hemoglobin non-invasively. Using light sources and detectors over the scalp, multi-wavelength light intensities are recorded as time series and converted to concentration changes of hemoglobin via modified Beer-Lambert law. Here, we describe a potential source for systematic error in the calculation of hemoglobin changes and light intensity measurements. Previous system characterization and analysis studies looked into various fNIRS parameters such as type of light source, number and selection of wavelengths, distance between light source and detector. In this study, we have analyzed the contribution of light detector surface area to the overall outcome. Results from Monte Carlo based digital phantoms indicated that selection of detector area is a critical system parameter in minimizing the error in concentration calculations. The findings here can guide the design of future fNIRS sensors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multi-Target Risk Assessment of Potentially Toxic Elements in Farmland Soil Based on the Environment-Ecological-Health Effect.

PubMed

Wang, Zhongyang; Meng, Bo; Zhang, Wei; Bai, Jinheng; Ma, Yingxin; Liu, Mingda

2018-05-28

There are potential impacts of Potentially Toxic Elements (PTEs) (e.g., Cd, Cr, Ni, Cu, As, Zn, Hg, and Pb) in soil from the perspective of the ecological environment and human health, and assessing the pollution and risk level of soil will play an important role in formulating policies for soil pollution control. Lingyuan, in the west of Liaoning Province, China, is a typical low-relief terrain of a hilly area. The object of study in this research is the topsoil of farmland in this area, of which 71 soil samples are collected. In this study, research methods, such as the Nemerow Index, Potential Ecological Hazard Index, Ecological Risk Quotient, Environmental Exposure Hazard Analysis, Positive Matrix Factorization Model, and Land Statistical Analysis, are used for systematical assessment of the pollution scale, pollution level, and source of PTEs, as well as the ecological environmental risks and health risks in the study area. The main conclusions are: The average contents of As, Cd, Cr, Cu, Hg, Zn, Ni, and Pb of the soil are 5.32 mg/kg, 0.31 mg/kg, 50.44 mg/kg, 47.05 mg/kg, 0.03 mg/kg, 79.36 mg/kg, 26.01 mg/kg, and 35.65 mg/kg, respectively. The contents of Cd, Cu, Zn, and Pb exceed the background value of local soil; Cd content of some study plots exceeds the National Soil Environmental Quality Standard Value (0.6 mg/kg), and the exceeding standard rate of study plots is 5.63%; the comprehensive potential ecological hazard assessment in the study area indicates that the PTEs are at a slight ecological risk; probabilistic hazard quotient assessment indicates that the influence of PTEs on species caused by Cu is at a slight level ( p = 10.93%), and Zn, Pb, and Cd are at an acceptable level. For the ecological process, Zn is at a medium level ( p = 25.78%), Cu is at a slight level (19.77%), and the influence of Cd and Pb are acceptable; human health hazard assessment states that the Non-carcinogenic comprehensive health hazard index HI = 0.16 < 1, indicating that PTEs in soil have no significant effect on people's health through exposure; the PMF model (Positive Matrix Factorization) shows that the contribution rates of agricultural source, industrial source, atmospheric dust source, and natural source are 13.15%, 25.33%, 18.47%, and 43.05%, respectively.

Soil organic phosphorus flows to water via critical and non-critical hydrological source areas

NASA Astrophysics Data System (ADS)

Wang, Ying; Surridge, Ben; Haygarth, Phil

2015-04-01

Soil organic phosphorus flows to water via critical and non-critical hydrological source areas Ying Wang, Ben W.J. Surridge, Philip M. Haygarth Lancaster Environment Centre, Lancaster University, LA1 4YQ, UK Critical source areas (CSAs) are zones in the landscape where easily connected hydrology coincides with a phosphorus (P) sources in the soil. The P export risks in CSAs are hypothesised to be higher compared with non-critical source areas (Non-CSAs) and specifically that the magnitudes of P forms in CSA areas were higher than Non-CSAs. Past research on CSAs has often neglected forms of organic P, such as DNA and phospholipids which are among the most potentially biodegradable organic P compounds. The objectives of this study were i) to quantify the magnitude of organic P compounds in agricultural soils and specifically determine whether these magnitudes differed significantly between CSAs and Non-CSAs; ii) determine the variation of P magnitude between and within individual fields; iii) identify the P delivery concentrations in soil solution after raining events in CSAs. The study focussed on soils collected from the Morland sub-catchment of the River Eden catchment in Cumbria, northern England. CSA and Non-CSA pairs were identified using the SCIMAP modelling and field assessment providing five CSA - Non-CSA pairs in total. The results showed that there are significant differences in the total P (TP) concentrations, the proportions of DNA-P, WETP (water extractable total P), WERP (water extractable reactive P) and WEUP (water extractable unreactive P) between CSA and Non-CSA. We also found that the concentrations of all the P forms showed distribution variation between fields or even within the same field. Liable organic P such as DNA-P and PLD-P was presented considerable proportions of total P in soil, especially DNA-P which had a good correlation with TP. DNA-P in the ten areas accounted for a considerable proportion of soil TP (4.9 to 16.6%). Given the potential lability and bioavailability of DNA and phospholipids, our data demonstrate that these soil organic P could be a potential pool to support plant nutrition and a potential contributor to water pollution problems. Furthermore, For a number of soil samples, comparisons were made between extraction of P within phospholipids and DNA and the results of 31 PNMR analyses, to provide further characterisation of the organic P fractions within these soils.Data of this study will also be presented concerning the forms and magnitudes of P fractions in runoff pathways across an agricultural catchment, including the prevalence of organic P in these pathways. Keywords: Organic P; Soil; CSA; DNA; Phospholipids

Using Simulated Ground Motions to Constrain Near-Source Ground Motion Prediction Equations in Areas Experiencing Induced Seismicity

NASA Astrophysics Data System (ADS)

Bydlon, S. A.; Dunham, E. M.

2016-12-01

Recent increases in seismic activity in historically quiescent areas such as Oklahoma, Texas, and Arkansas, including large, potentially induced events such as the 2011 Mw 5.6 Prague, OK, earthquake, have spurred the need for investigation into expected ground motions associated with these seismic sources. The neoteric nature of this seismicity increase corresponds to a scarcity of ground motion recordings within 50 km of earthquakes Mw 3.0 and greater, with increasing scarcity at larger magnitudes. Gathering additional near-source ground motion data will help better constraints on regional ground motion prediction equations (GMPEs) and will happen over time, but this leaves open the possibility of damaging earthquakes occurring before potential ground shaking and seismic hazard in these areas are properly understood. To aid the effort of constraining near-source GMPEs associated with induced seismicity, we integrate synthetic ground motion data from simulated earthquakes into the process. Using the dynamic rupture and seismic wave propagation code waveqlab3d, we perform verification and validation exercises intended to establish confidence in simulated ground motions for use in constraining GMPEs. We verify the accuracy of our ground motion simulator by performing the PEER/SCEC layer-over-halfspace comparison problem LOH.1 Validation exercises to ensure that we are synthesizing realistic ground motion data include comparisons to recorded ground motions for specific earthquakes in target areas of Oklahoma between Mw 3.0 and 4.0. Using a 3D velocity structure that includes a 1D structure with additional small-scale heterogeneity, the properties of which are based on well-log data from Oklahoma, we perform ground motion simulations of small (Mw 3.0 - 4.0) earthquakes using point moment tensor sources. We use the resulting synthetic ground motion data to develop GMPEs for small earthquakes in Oklahoma. Preliminary results indicate that ground motions can be amplified if the source is located in the shallow, sedimentary sequence compared to the basement. Source depth could therefore be an important variable to define explicitly in GMPEs instead of being incorporated into traditional distance metrics. Future work will include the addition of dynamic sources to develop GMPEs for large earthquakes.

Investigation of large-area multicoil inductively coupled plasma sources using three-dimensional fluid model

NASA Astrophysics Data System (ADS)

Brcka, Jozef

2016-07-01

A multi inductively coupled plasma (ICP) system can be used to maintain the plasma uniformity and increase the area processed by a high-density plasma. This article presents a source in two different configurations. The distributed planar multi ICP (DM-ICP) source comprises individual ICP sources that are not overlapped and produce plasma independently. Mutual coupling of the ICPs may affect the distribution of the produced plasma. The integrated multicoil ICP (IMC-ICP) source consists of four low-inductance ICP antennas that are superimposed in an azimuthal manner. The identical geometry of the ICP coils was assumed in this work. Both configurations have highly asymmetric components. A three-dimensional (3D) plasma model of the multicoil ICP configurations with asymmetric features is used to investigate the plasma characteristics in a large chamber and the operation of the sources in inert and reactive gases. The feasibility of the computational calculation, the speed, and the computational resources of the coupled multiphysics solver are investigated in the framework of a large realistic geometry and complex reaction processes. It was determined that additional variables can be used to control large-area plasmas. Both configurations can form a plasma, that azimuthally moves in a controlled manner, the so-called “sweeping mode” (SM) or “polyphase mode” (PPM), and thus they have the potential for large-area and high-density plasma applications. The operation in the azimuthal mode has the potential to adjust the plasma distribution, the reaction chemistry, and increase or modulate the production of the radicals. The intrinsic asymmetry of the individual coils and their combined operation were investigated within a source assembly primarily in argon and CO gases. Limited investigations were also performed on operation in CH4 gas. The plasma parameters and the resulting chemistry are affected by the geometrical relation between individual antennas. The aim of this work is to incorporate the technological, computational, dimensional scaling, and reaction chemistry aspects of the plasma under one computational framework. The 3D simulation is utilized to geometrically scale up the reactive plasma that is produced by multiple ICP sources.

Null-space Monte Carlo particle tracking to assess groundwater PCE (Tetrachloroethene) diffuse pollution in north-eastern Milan functional urban area.

PubMed

Alberti, Luca; Colombo, Loris; Formentin, Giovanni

2018-04-15

The Lombardy Region in Italy is one of the most urbanized and industrialized areas in Europe. The presence of countless sources of groundwater pollution is therefore a matter of environmental concern. The sources of groundwater contamination can be classified into two different categories: 1) Point Sources (PS), which correspond to areas releasing plumes of high concentrations (i.e. hot-spots) and 2) Multiple-Point Sources (MPS) consisting in a series of unidentifiable small sources clustered within large areas, generating an anthropogenic diffuse contamination. The latter category frequently predominates in European Functional Urban Areas (FUA) and cannot be managed through standard remediation techniques, mainly because detecting the many different source areas releasing small contaminant mass in groundwater is unfeasible. A specific legislative action has been recently enacted at Regional level (DGR IX/3510-2012), in order to identify areas prone to anthropogenic diffuse pollution and their level of contamination. With a view to defining a management plan, it is necessary to find where MPS are most likely positioned. This paper describes a methodology devised to identify the areas with the highest likelihood to host potential MPS. A groundwater flow model was implemented for a pilot area located in the Milan FUA and through the PEST code, a Null-Space Monte Carlo method was applied in order to generate a suite of several hundred hydraulic conductivity field realizations, each maintaining the model in a calibrated state and each consistent with the modelers' expert-knowledge. Thereafter, the MODPATH code was applied to generate back-traced advective flowpaths for each of the models built using the conductivity field realizations. Maps were then created displaying the number of backtracked particles that crossed each model cell in each stochastic calibrated model. The result is considered to be representative of the FUAs areas with the highest likelihood to host MPS responsible for diffuse contamination. Copyright © 2017 Elsevier B.V. All rights reserved.

Identification of phosphorus emission hotspots in agricultural catchments

PubMed Central

Kovacs, Adam; Honti, Mark; Zessner, Matthias; Eder, Alexander; Clement, Adrienne; Blöschl, Günter

2012-01-01

An enhanced transport-based management approach is presented, which is able to support cost-effective water quality management with respect to diffuse phosphorus pollution. Suspended solids and particulate phosphorus emissions and their transport were modeled in two hilly agricultural watersheds (Wulka River in Austria and Zala River in Hungary) with an improved version of the catchment-scale PhosFate model. Source and transmission areas were ranked by an optimization method in order to provide a priority list of the areas of economically efficient (optimal) management alternatives. The model was calibrated and validated at different gauges and for various years. The spatial distribution of the emissions shows that approximately one third of the catchment area is responsible for the majority of the emissions. However, only a few percent of the source areas can transport fluxes to the catchment outlet. These effective source areas, together with the main transmission areas are potential candidates for improved management practices. In accordance with the critical area concept, it was shown that intervention with better management practices on a properly selected small proportion of the total area (1–3%) is sufficient to reach a remarkable improvement in water quality. If soil nutrient management is also considered in addition to water quality, intervention on 4–12% of the catchment areas can fulfill both aspects. PMID:22771465

Starch Product of Wild Plants Species Jalawure (Tacca leontopetaloides L.) Kuntze as The Source of Food Security in The South Coastal West Java

NASA Astrophysics Data System (ADS)

Wardah; Sambas, E. N.; Ridwan; Ariani, D.

2017-04-01

Majority of people of South coast of West Java, from Sukabumi, Cianjur, Garut are fishermen. Natural conditions are very dry and the area of land for agriculture, particularly rice cultivation is minimal. So that the condition of the society is more directed to high enough levels of food insecurity. Because coastal areas tend to have a longer dry season from rainfall. Results of research conducted in the years 2013 - 2016 in the area of Pelabuhan Ratu, Cidaun (Cianjur), Coastal area of Jayanti, Ranca Buaya, Mekar Mukti, and along the coast until Pameungpeuk, Leuweung Sancang, is known that jalawure plant which grows wild at South-coast region of West Java is precisely the alternative solution to address food insecurity. The results of the starch flour is a source of carbohydrate that is high enough to be used as a substitute for rice and wheat. Another potential source of jalawure nutrition is also recommended for diabetics consumption.

Anthropogenic Organic Compounds in Ground Water and Finished Water of Community Water Systems in the Northern Tampa Bay Area, Florida, 2002-04

USGS Publications Warehouse

Metz, Patricia A.; Delzer, Gregory C.; Berndt, Marian P.; Crandall, Christy A.; Toccalino, Patricia L.

2007-01-01

As part of the U.S. Geological Survey's (USGS's) National Water-Quality Assessment (NAWQA) Program, a Source Water-Quality Assessment (SWQA) was conducted in the unconfined and semiconfined portions of the Upper Floridan aquifer system during 2002-04. SWQAs are two-phased sampling activities, wherein phase 1 was designed to evaluate the occurrence of 258 anthropogenic organic compounds (AOCs) in ground water used as source water for 30 of the largest-producing community water system (CWS) wells in the northern Tampa Bay area, Florida. The 258 AOCs included volatile organic compounds (VOCs), pesticides, and other anthropogenic organic compounds (OAOCs). Phase 2 was designed to monitor concentrations in the source water and also the finished water of CWSs for compounds most frequently detected during phase 1. During phase 1 of the SWQA study, 31 of the 258 AOCs were detected in source-water samples collected from CWS wells at low concentrations (less than 1.0 microgram per liter (ug/L)). Twelve AOCs were detected in at least 10 percent of samples. Concentrations from 16 of the 31 detected AOCs were about 2 to 5 orders of magnitude below human-health benchmarks indicating that concentrations were unlikely to be of potential human-health concern. The potential human-health relevance for the remaining 15 detected unregulated AOCs could not be evaluated because no human-health benchmarks were available for these compounds. Hydrogeology, population, and land use were examined to evaluate the effects of these variables on the source water monitored. Approximately three times as many detections of VOCs (27) and pesticides (34) occurred in unconfined areas than in the semiconfined areas (8 VOCs, 14 pesticides). In contrast, 1 OAOC was detected in unconfined areas, and 13 OAOCs were detected in semiconfined areas with 9 of the OAOC detections occurring in samples from two wells located near septic systems. Analyses of population and land use indicated that the number of compounds detected increased as the population surrounding each well increased. Detection frequencies and concentrations for VOCs (particularly chloroform) and pesticides were highest in residential land-use areas. The results of source-water samples from the 30 CWS wells monitored during phase 1 of this SWQA study were compared to four locally conducted studies. These general comparisons indicate that the occurrence of VOCs in other studies is similar to their occurrence in source water of CWSs monitored as part of this SWQA. However, pesticide compounds, especially atrazine and its breakdown products, occurred more frequently in the SWQA study than in the other four studies. Phase 2 of the SWQA assessed AOCs in samples from 11 of the 30 CWS wells and the associated finished water. Overall, 42 AOCs were detected in either source water or finished water and more compounds were detected in finished water than in source water. Specifically, 22 individual AOCs were detected in source water and 27 AOCs were detected in finished water. The total number of detections was greater in the finished water (80) than in the source water (49); however, this was largely due to the creation of disinfection by-products (DBPs) during water treatment. Excluding DBPs, about the same number of total detections was observed in source water (40) and finished water (44). During phase 2, AOC detected concentrations ranged from E0.003 (estimated) to 1,140 ug/L in the source water and from E0.003 to 36.3 ug/L in the finished water. Concentrations of 24 of the 42 compounds were compared to human-health benchmarks and were about 1 to 5 orders of magnitude below their human-health benchmarks indicating that concentrations are unlikely to be of potential human-health concern, excluding DBPs. Concentrations of carbon tetrachloride, however, were within 10 percent of its human-health benchmark, which is considered a level that may warrant inclusion of the compound in a low-concentration, t

Understanding Contaminants Associated with Mineral Deposits

USGS Publications Warehouse

Verplanck, Philip L.

2008-01-01

Interdisciplinary studies by the U.S. Geological Survey (USGS) have resulted in substantial progress in understanding the processes that control *the release of metals and acidic water from inactive mines and mineralized areas, *the transport of metals and acidic water to streams, and *the fate and effect of metals and acidity on downstream ecosystems. The potential environmental effects associated with abandoned and inactive mines, resulting from the complex interaction of a variety of chemical and physical processes, is an area of study that is important to the USGS Mineral Resources Program. Understanding the processes contributing to the environmental effects of abandoned and inactive mines is also of interest to a wide range of stakeholders, including both those responsible for managing lands with historically mined areas and those responsible for anticipating environmental consequences of future mining operations. The recently completed (2007) USGS project entitled 'Process Studies of Contaminants Associated with Mineral Deposits' focused on abandoned and inactive mines and mineralized areas in the Rocky Mountains of Montana, Colorado, New Mexico, Utah, and Arizona, where there are thousands of abandoned mines. Results from these studies provide new information that advances our understanding of the physical and biogeochemical processes causing the mobilization, transport, reaction, and fate of potentially toxic elements (including aluminum, arsenic, cadmium, copper, iron, lead, and zinc) in mineralized near-surface systems and their effects on aquatic and riparian habitat. These interdisciplinary studies provide the basis for scientific decisionmaking and remedial action by local, State, and Federal agencies charged with minimizing the effects of potentially toxic elements on the environment. Current (2007) USGS research highlights the need to understand (1) the geologic sources of metals and acidity and the geochemical reactions that release them from their sources, (2) the pathways that facilitate transport from those sources, and (3) the processes that control the fate of the elements once released from the sources. Experts in the fields of economic geology, structural geology, mineralogy, geophysics, geochemistry, hydrology, ground-water modeling, microbiology, and toxicology came together for a series of studies that address these relationships on scales ranging from the microscopic to the watershed. This Circular presents results and highlights from the detailed, interdisciplinary studies that include investigations in both mining-affected areas and mineralized but unmined areas. The first section of the Circular describes laboratory and site-scale field investigations that primarily focus on mineralogic and biologic controls on the source and release of metals and acidity from mine-waste rock and hydrothermally altered areas. The second section describes a set of basin- to watershed-scale studies that not only investigate the source and release of metals and acidity but also the transport of these constituents away from the source areas. The third section is a summary of results from postremediation ecosystem monitoring. For more information on these and other project-related studies, please visit the project Web site at http://minerals.cr.usgs.gov/projects/contaminants/index.html. The Web site includes a complete bibliography and detailed descriptions of each interdisciplinary study.

The significance of "geothermal microzonation" for the correct planning of low-grade source geothermal systems

NASA Astrophysics Data System (ADS)

Viccaro, Marco; Pezzino, Antonino; Belfiore, Giuseppe Maria; Campisano, Carlo

2016-04-01

Despite the environmental-friendly energy systems are solar thermal technologies, photovoltaic and wind power, other advantageous technologies exist, although they have not found wide development in countries such as Italy. Given the almost absent environmental impact and the rather favorable cost/benefit ratio, low-enthalpy geothermal systems are, however, likely to be of strategic importance also in Italy during the next years. The importance of geology for a sustainable exploitation of the ground through geothermal systems from low-grade sources is becoming paramount. Specifically, understanding of the lithological characteristics of the subsurface along with structures and textures of rocks is essential for a correct planning of the probe/geo-exchanger field and their associated ground source heat pumps. The complex geology of Eastern Sicily (Southern Italy), which includes volcanic, sedimentary and metamorphic units over limited extension, poses the question of how thermal conductivity of rocks is variable at the scale of restricted areas (even within the same municipality). This is the innovative concept of geothermal microzonation, i.e., how variable is the geothermal potential as a function of geology at the microscale. Some pilot areas have been therefore chosen to test how the geological features of the subsurface can influence the low-enthalpy geothermal potential of an area. Our geologically based evaluation and micro-zonation of the low-grade source geothermal potential of the selected areas have been verified to be fundamental for optimization of all the main components of a low-enthalpy geothermal system. Saving realization costs and limiting the energy consumption through correct sizing of the system are main ambitions to have sustainable development of this technology with intensive utilization of the subsurface. The variegated territory of countries such as Italy implies that these goals can be only reached if, primarily, the geological features of the shallow subsurface (i.e., chemical-physical characteristics of rocks and fluids of the first 100 m below the ground) are appropriately constrained.

Geology and total petroleum systems of the West-Central Coastal province (7203), West Africa

USGS Publications Warehouse

Brownfield, Michael E.; Charpentier, Ronald R.

2006-01-01

The West-Central Coastal Province of the Sub-Saharan Africa Region consists of the coastal and offshore areas of Cameroon, Equatorial Guinea, Gabon, Democratic Republic of the Congo, Republic of the Congo, Angola (including the disputed Cabinda Province), and Namibia. The area stretches from the east edge of the Niger Delta south to the Walvis Ridge. The West-Central Coastal Province includes the Douala, Kribi-Campo, Rio Muni, Gabon, Congo, Kwanza, Benguela, and Namibe Basins, which together form the Aptian salt basin of equatorial west Africa. The area has had significant exploration for petroleum; more than 295 oil fields have been discovered since 1954. Since 1995, several giant oil fields have been discovered, especially in the deep-water area of the Congo Basin. Although many total petroleum systems may exist in the West-Central Coastal Province, only four major total petroleum systems have been defined. The area of the province north of the Congo Basin contains two total petroleum systems: the Melania-Gamba Total Petroleum System, consisting of Lower Cretaceous source and reservoir rocks, and the Azile-Senonian Total Petroleum System, consisting of Albian to Turonian source rocks and Cretaceous reservoir rocks. Two assessment units are defined in the West-Central Coastal Province north of the Congo Basin: the Gabon Subsalt and the Gabon Suprasalt Assessment Units. The Congo Basin contains the Congo Delta Composite Total Petroleum System, consisting of Lower Cretaceous to Tertiary source and reservoir rocks. The Central Congo Delta and Carbonate Platform and the Central Congo Turbidites Assessment Units are defined in the Congo Delta Composite Total Petroleum System. The area south of the Congo Basin contains the Cuanza Composite Total Petroleum System, consisting of Lower Cretaceous to Tertiary source and reservoir rocks. The Cuanza-Namibe Assessment Unit is defined in the Cuanza Composite Total Petroleum System. The U.S. Geological Survey (USGS) assessed the potential for undiscovered conventional oil and gas resources in this province as part of its World Petroleum Assessment 2000. The USGS estimated a mean of 29.7 billion barrels of undiscovered conventional oil, 88.0 trillion cubic feet of gas, and 4.2 billion barrels of natural gas liquids. Most of the hydrocarbon potential remains in the offshore waters of the province in the Central Congo Turbidites Assessment Unit. Large areas of the offshore parts of the Kwanza, Douala, Kribi-Campo, and Rio Muni Basins are underexplored, considering their size, and current exploration activity suggests that the basins have hydrocarbon potential. Since about 1995, the offshore part of the Congo Basin has become a major area for new field discoveries and for hydrocarbon exploration, and many deeper water areas in the basin have excellent hydrocarbon potential. Gas resources may be significant and accessible in areas where the zone of oil generation is relatively shallow.

49 CFR 176.138 - Deck stowage.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., machinery exhaust, galley uptake, locker used for combustible stores, or other potential sources of ignition. They must be clear of walkways and cargo working areas, fire hydrants, steam pipes, and means of access...

Understanding Hydrological Processes in Variable Source Areas in the Glaciated Northeastern US Watersheds under Variable Climate Conditions

NASA Astrophysics Data System (ADS)

Steenhuis, T. S.; Azzaino, Z.; Hoang, L.; Pacenka, S.; Worqlul, A. W.; Mukundan, R.; Stoof, C.; Owens, E. M.; Richards, B. K.

2017-12-01

The New York City source watersheds in the Catskill Mountains' humid, temperate climate has long-term hydrological and water quality monitoring data It is one of the few catchments where implementation of source and landscape management practices has led to decreased phosphorus concentration in the receiving surface waters. One of the reasons is that landscape measures correctly targeted the saturated variable source runoff areas (VSA) in the valley bottoms as the location where most of the runoff and other nonpoint pollutants originated. Measures targeting these areas were instrumental in lowering phosphorus concentration. Further improvements in water quality can be made based on a better understanding of the flow processes and water table fluctuations in the VSA. For that reason, we instrumented a self-contained upland variable source watershed with a landscape characteristic of a soil underlain by glacial till at shallow depth similar to the Catskill watersheds. In this presentation, we will discuss our experimental findings and present a mathematical model. Variable source areas have a small slope making gravity the driving force for the flow, greatly simplifying the simulation of the flow processes. The experimental data and the model simulations agreed for both outflow and water table fluctuations. We found that while the flows to the outlet were similar throughout the year, the discharge of the VSA varies greatly. This was due to transpiration by the plants which became active when soil temperatures were above 10oC. We found that shortly after the temperature increased above 10oC the baseflow stopped and only surface runoff occurred when rainstorms exceeded the storage capacity of the soil in at least a portion of the variable source area. Since plant growth in the variable source area was a major variable determining the base flow behavior, changes in temperature in the future - affecting the duration of the growing season - will affect baseflow and related transport of nutrient and other chemicals many times more than small temperature related increases in potential evaporation rate. This in turn will directly change the water availability and pollutant transport in the many surface source watersheds with variable source area hydrology.

Preliminary study of Songa-Wayaua geothermal prospect area using volcanostratigraphy and remote sensing analysis

NASA Astrophysics Data System (ADS)

Asokawaty, Ribka; Nugroho, Indra; Satriana, Joshua; Hafidz, Muhamad; Suryantini

2017-12-01

Songa-Wayaua geothermal prospect area is located on Bacan Island, Northern Molluca Province. Geothermal systems in this area associated with three Quartenary volcanoes, such as Mt. Pele-pele, Mt. Lansa, and Mt. Bibinoi. Based on literature study, five surface manifestations such as hot springs and alteration occurred within this area. The active manifestations indicate that Songa-Wayaua area has potential geothermal resource. This study objective is to evaluate Songa-Wayaua geothermal system on preliminary study stage by using volcanostratigraphy and remote sensing analysis to delineate the boundary of geothermal system area. The result of this study showed that Songa-Wayaua prospect area has four heat sources potential (e.g. Pele-pele Hummock, Lansa Hummock, Songa Hummock, and Bibinoi Hummock), controlled by geological structure presented by Pele-pele Normal Fault, and had three places as the recharge and discharge area which are very fulfilling as a geothermal system.

Integrated Potential-field Studies in Support of Energy Resource Assessment in Frontier Areas of Alaska

NASA Astrophysics Data System (ADS)

Phillips, J. D.; Saltus, R. W.; Potter, C. J.; Stanley, R. G.; Till, A. B.

2008-05-01

In frontier areas of Alaska, potential-field studies play an important role in characterizing the geologic structure of sedimentary basins having potential for undiscovered oil and gas resources. Two such areas are the Yukon Flats basin in the east-central interior of Alaska, and the coastal plain of the Arctic National Wildlife Refuge (ANWR) in northeastern Alaska. The Yukon Flats basin is a potential source of hydrocarbon resources for local consumption and possible export. Knowledge of the subsurface configuration of the basin is restricted to a few seismic reflection profiles covering a limited area and one well. The seismic profiles were reprocessed and reinterpreted in preparation for an assessment of the oil and gas resources of the basin. The assessment effort required knowledge of the basin configuration away from the seismic profiles, as well as an understanding of the nature of the underlying basement. To extend the interpretation of the basin thickness across the entire area of the basin, an iterative Jachens-Moring gravity inversion was performed on gridded quasi-isostatic residual gravity anomaly data. The inversion was constrained to agree with the interpreted basement surface along the seismic profiles. In addition to the main sedimentary depocenter interpreted from the seismic data as having over 8 km of fill, the gravity inversion indicated a depocenter with over 7 km of fill in the Crooked Creek sub-basin. Results for the Crooked Creek sub-basin are consistent with magnetic and magnetotelluric modeling, but they await confirmation by drilling or seismic profiling. Whether hydrocarbon source rocks are present in the pre-Cenozoic basement beneath Yukon Flats is difficult to determine because extensive surficial deposits obscure the bedrock geology, and no deep boreholes penetrate basement. The color and texture patterns in a red-green-blue composite image consisting of reduced-to-the-pole aeromagnetic data (red), magnetic potential (blue), and basement gravity (green) highlight domains with common geophysical characteristics and, by inference, lithology. The observed patterns suggest that much of the basin is underlain by Devonian to Jurassic oceanic rocks that probably have little or no potential for hydrocarbon generation. The coastal plain surficial deposits in the northern part of ANWR conceal another frontier basin with hydrocarbon potential. Proprietary aeromagnetic and gravity data were used, along with seismic reflection profiles, to construct a structural and stratigraphic model of this highly deformed sedimentary basin for use in an energy resource assessment. Matched-filtering techniques were used to separate short-wavelength magnetic and gravity anomalies attributed to sources near the top of the sedimentary section from longer-wavelength anomalies attributed to deeper basin and basement sources. Models along the seismic reflection lines indicate that the primary sources of the short-wavelength anomalies are folded and faulted sedimentary beds truncated at the Pleistocene erosion surface. In map view, the aeromagnetic and gravity anomalies produced by the sedimentary units were used to identify possible structural trapping features and geometries, but they also indicated that these features may be significantly disrupted by faulting.

An overview on source rocks and the petroleum system of the central Upper Rhine Graben

NASA Astrophysics Data System (ADS)

Böcker, Johannes; Littke, Ralf; Forster, Astrid

2017-03-01

The petroleum system of the Upper Rhine Graben (URG) comprises multiple reservoir rocks and four major oil families, which are represented by four distinct source rock intervals. Based on geochemical analyses of new oil samples and as a review of chemical parameter of former oil fields, numerous new oil-source rock correlations were obtained. The asymmetric graben resulted in complex migration pathways with several mixed oils as well as migration from source rocks into significantly older stratigraphic units. Oldest oils originated from Liassic black shales with the Posidonia Shale as main source rock (oil family C). Bituminous shales of the Arietenkalk-Fm. (Lias α) show also significant source rock potential representing the second major source rock interval of the Liassic sequence. Within the Tertiary sequence several source rock intervals occur. Early Tertiary coaly shales generated high wax oils that accumulated in several Tertiary as well as Mesozoic reservoirs (oil family B). The Rupelian Fish Shale acted as important source rock, especially in the northern URG (oil family D). Furthermore, early mature oils from the evaporitic-salinar Corbicula- and Lower Hydrobienschichten occur especially in the area of the Heidelberg-Mannheim-Graben (oil family A). An overview on potential source rocks in the URG is presented including the first detailed geochemical source rock characterization of Middle Eocene sediments (equivalents to the Bouxwiller-Fm.). At the base of this formation a partly very prominent sapropelic coal layer or coaly shale occurs. TOC values of 20-32 % (cuttings) and Hydrogen Index (HI) values up to 640-760 mg HC/g TOC indicate an extraordinary high source rock potential, but a highly variable lateral distribution in terms of thickness and source rock facies is also supposed. First bulk kinetic data of the sapropelic Middle Eocene coal and a coaly layer of the `Lymnäenmergel' are presented and indicate oil-prone organic matter characterized by low activation energies. These sediments are considered as most important source rocks of numerous high wax oils (oil family B) in addition to the coaly source rocks from the (Lower) Pechelbronn-Schichten (Late Eocene). Migration pathways are significantly influenced by the early graben evolution. A major erosion period occurred during the latest Cretaceous. The uplift center was located in the northern URG area, resulting in SSE dipping Mesozoic strata in the central URG. During Middle Eocene times a second uplift center in the Eifel area resulted in SW-NE-directed shore lines in the central URG and contemporaneous south-southeastern depocenters during marine transgression from the south. This structural setting resulted in a major NNW-NW-directed and topography-driven migration pattern for expelled Liassic oil in the fractured Mesozoic subcrop below sealing Dogger α clays and basal Tertiary marls.

Phase I Source Investigation, Heckathorn Superfund Site, Richmond, California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kohn, Nancy P; Evans, Nathan R

This report represents Phase I of a multi-phase approach to a source investigation of DDT at the Heckathorn Superfund Site, Richmond, California, the former site of a pesticide packaging plant, and the adjacent waterway, the Lauritzen Channel. Potential identified sources of contamination were from sloughed material from undredged areas (such as side banks) and from outfall pipes. Objectives of Phase I included the (1) evaluation of pesticide concentrations associated with discharge from outfalls, (2) identification of additional outfalls in the area, (3) identification of type, quantity, and distribution of sediment under the Levin pier, (4) quantification of pesticide concentrations inmore » sediment under the pier, and (5) evaluation of sediment structure and slope stability under the pier. Field operations included the collection of sediment directly from inside the mouths of outfall pipes, when possible, or the deployment of specially designed particle traps where direct sampling was problematic. Passive water samplers were placed at the end of known outfall pipes and analyzed for DDT and other pesticides of concern. Underwater dive surveys were conducted beneath the Levin pier to document type, slope, and thickness of sediment. Samples were collected at locations of interest and analyzed for contaminants. Also sampled was soil from bank areas, which were suspected of potentially contributing to continued DDT contamination of the Lauritzen Channel through erosion and groundwater leaching. The Phase I Source Investigation was successful in identifying significant sources of DDT contamination to Lauritzen Channel sediment. Undredged sediment beneath the Levin pier that has been redistributed to the channel is a likely source. Two outfalls tested bear further investigation. Not as well-defined are the contributions of bank erosional material and groundwater leaching. Subsequent investigations will be based on the results of this first phase.« less

Detrital rutile geochemistry and thermometry from the Dabie orogen: Implications for source-sediment links in a UHPM terrane

NASA Astrophysics Data System (ADS)

Liu, Lei; Xiao, Yilin; Wörner, G.; Kronz, A.; Simon, K.; Hou, Zhenhui

2014-08-01

This study explores the potential of detrital rutile geochemistry and thermometry as a provenance tracer in rocks from the Central Dabie ultrahigh-pressure metamorphic (UHPM) zone in east-central China that formed during Triassic continental collision. Trace element data of 176 detrital rutile grains selected from local river sediments and 91 rutile grains from distinct bedrocks in the Shuanghe and Bixiling areas, obtained by both electron microprobe (EMP) and in situ LA-ICP-MS analyses, suggest that geochemical compositions and thermometry of detrital rutiles are comparable to those from their potential source rocks. After certification of the Cr-Nb discrimination method for the Central Dabie UHPM zone, we show that 29% of the detrital rutiles in the Shuanghe area were derived from metamafic sources whereas in the Bixiling area that it is up to 76%. Furthermore, the proportion of distinct types of detrital rutiles combined with modal abundances of rutile in metapelites and metamafic bedrocks can be used to estimate the proportion of different source lithologies. Based on this method the proportion of mafic source rocks was estimated to ∼10% at Shuanghe and >60% at Bixiling, respectively, which is consistent with the proportions of eclogite (the major rutile-bearing metamafic rock) distribution in the field. Therefore, the investigation of detrital rutiles is a potential way to evaluate the proportion of metamafic rocks and even to prospect for metamafic bodies in UHPM terranes. Zr-in-rutile temperatures were calculated at different pressures and compared with temperatures derived from rock-in rutiles and garnet-clinopyroxene Fe-Mg thermometers. Temperatures calculated for detrital rutiles range from 606 °C to 707 °C and 566 °C to 752 °C in Shuanghe and Bixiling, respectively, at P = 3 GPa with an average temperatures of ca. 630 °C for both areas. These temperature averages and ranges are similar to those calculated for rutiles from surrounding source rocks. Combined with comparable Zr distribution characteristics between detrital and source rock rutiles, demonstrating a close source-sediment link for rutiles from clastic and rock in UHPM terranes. Thus rutiles can be accurate tracers of source rock lithologies in sedimentary provenance studies even at a small regional scale. In Bixiling, Nb/Ta ratios of metamafic and metapelitic detrital rutiles fall between 11.0 to 27.3 and 7.7 to 20.5, respectively. In contrast, in Shuanghe, these ratios are highly variable, ranging from 10.9 to 71.0 and 7.6 to 87.1, respectively. When ignoring four outlier compositions with extremely high Nb/Ta in Shuanghe, a distinct clustering of Nb/Ta ratios in rutiles is shown: metapelitic detrital rutiles have Nb/Ta of 7-40 vs. metamafic detrital rutiles with Nb/Ta = 11-25. The Nb/Ta characteristics in detrital rutiles from both areas may reflect the degree of fluid-rock interaction during metamorphism and/or different source lithologies. Therefore, the trace element compositions in detrital rutiles can accurately trace the lithology, proportion and fluid-rock interaction of different source rocks.

Noise from high speed maglev systems: Noise sources, noise criteria, preliminary design guidelines for noise control, recommendations for acoustical test facility for maglev research. Final report, July 1991-October 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hanson, C.E.; Abbot, P.; Dyer, I.

1993-01-01

Noise levels from magnetically-levitated trains (maglev) at very high speed may be high enough to cause environmental noise impact in residential areas. Aeroacoustic sources dominate the sound at high speeds and guideway vibrations generate noticeable sound at low speed. In addition to high noise levels, the startle effect as a result of sudden onset of sound from a rapidly moving nearby maglev vehicle may lead to increased annoyance to neighbors of a maglev system. The report provides a base for determining the noise consequences and potential mitigation for a high speed maglev system in populated areas of the United States.more » Four areas are included in the study: (1) definition of noise sources; (2) development of noise criteria; (3) development of design guidelines; and (4) recommendations for a noise testing facility.« less

Identification of sources and seasonal variability of organic matter in Lake Sihwa and surrounding inland creeks, South Korea.

PubMed

Lee, Yeonjung; Hong, Seongjin; Kim, Min-Seob; Kim, Dahae; Choi, Bo-Hyung; Hur, Jin; Khim, Jong Seong; Shin, Kyung-Hoon

2017-06-01

Coastal areas are subjected to significant allochthonous organic matter deposits from surrounding areas; however, limited information is available on the source and delivery of this organic matter. In this study, to assess seasonal changes in the sources of organic matter in Lake Sihwa (Korea), biodegradability, fluorescence property, and stable isotopic compositions (carbon, nitrogen, and sulfur) of the organic matter were determined. Water samples were collected from the inner lake (n = 9) and inland creeks (n = 10) in five separate events, from November 2012 to October 2013. Organic matter originating from rural, urban, and industrial areas was examined as the potential sources. The organic matter contents and biodegradability in the industrial area were the highest, whereas low concentrations and poor biodegradability of organic matter were found in the rural area, and moderate properties were observed in the urban area. In Lake Sihwa, a large concentration of total organic matter and enhanced biodegradability were observed during March and August. However, main source of organic matter differed between the sampling events. The largest contribution of organic matter, deriving from marine phytoplankton, was found in March. On the other hand, in August, the organic matter originating from the industrial area, which is characterized by high levels of heavy metals and persistent organic pollutants, was significantly increased. Our results could be useful to enhance the management of water bodies aimed at reducing the organic matter concentrations and improving the water quality of Lake Sihwa, and even that of the Yellow Sea. Copyright © 2017 Elsevier Ltd. All rights reserved.

Wood and coal cofiring in interior Alaska: utilizing woody biomass from wildland defensible-space fire treatments and other sources.

Treesearch

David L. Nicholls; Stephen E. Patterson; Erin Uloth

2006-01-01

Cofiring wood and coal at Fairbanks, Alaska, area electrical generation facilities represents an opportunity to use woody biomass from clearings within the borough's wildland-urban interface and from other sources, such as sawmill residues and woody material intended for landfills. Potential benefits of cofiring include air quality improvements, reduced greenhouse...

Flushing of distal hillslopes as an alternative source of stream dissolved organic carbon in a headwater catchment

Treesearch

John P. Gannon; Scott W. Bailey; Kevin J. McGuire; James B. Shanley

2015-01-01

We investigated potential source areas of dissolved organic carbon (DOC) in headwater streams by examining DOC concentrations in lysimeter, shallow well, and stream water samples from a reference catchment at the Hubbard Brook Experimental Forest. These observations were then compared to high-frequency temporal variations in fluorescent dissolved organic matter (FDOM)...

Determination of instream metal loads using tracer-injection and synoptic-sampling techniques, Wightman Fork, southwestern Colorado, July 1999

USGS Publications Warehouse

Ortiz, Roderick F.

2001-01-01

In July 1999, a tracer-injection study was conducted concurrently with synoptic sampling to generate mass-load profiles in Wightman Fork near the Summitville Mine site. The mine site is located in the San Juan Mountains of southwestern Colorado at an elevation of about 3,500 meters above sea level. Metal loads increased substantially along the 2,815-meter study reach along the boundary of the mine site. Spatial determinations of dissolved aluminum, copper, iron, manganese, and zinc loads were used to identify potential source areas to the stream. Overall, four source areas appeared to contribute most of the specific load at the end of the study reach. One source area was along a 60-meter reach downgradient from the toe of the North Waste Dump that generally corresponded to a region of radial faults. Another source area was a short reach that included inputs from the Summitville Water Treatment Facility and the Pump House Fault. In July 1999, seepage from the Summitville Dam Impoundment was a substantial contributor of metal load at the end of the study reach. Finally, the metal load contributed along a 60-meter reach that included Cropsy Creek is considered a substantial source of metal load to Wightman Fork.

Self-Esteem, Creativity, and Music: Implications and Directions for Research.

ERIC Educational Resources Information Center

VanderArk, Sherman

1989-01-01

This paper seeks to give potentially pertinent information and ideas for the development of a model and of hypotheses that are relevant in terms of combining the areas of self-concept and creativity. Selected sources from the areas of psychology, education, and music education are presented as the basis for ideas and thoughts for further research.…

Human influenza A (H5N1) cases, urban areas of People's Republic of China, 2005-2006.

PubMed

Yu, Hongjie; Feng, Zijian; Zhang, Xianfeng; Xiang, Nijuan; Huai, Yang; Zhou, Lei; Li, Zhongjie; Xu, Cuiling; Luo, Huiming; He, Jianfeng; Guan, Xuhua; Yuan, Zhengan; Li, Yanting; Xu, Longshan; Hong, Rongtao; Liu, Xuecheng; Zhou, Xingyu; Yin, Wenwu; Zhang, Shunxiang; Shu, Yuelong; Wang, Maowu; Wang, Yu; Lee, Chin-Kei; Uyeki, Timothy M; Yang, Weizhong

2007-07-01

We investigated potential sources of infection for 6 confirmed influenza A (H5N1) patients who resided in urban areas of People's Republic of China. None had known exposure to sick poultry or poultry that died from illness, but all had visited wet poultry markets before illness.

Mapping lacustrine syn-rift reservoir distribution using spectral attributes: A case study of the Pematang Brownshale Central Sumatra Basin

NASA Astrophysics Data System (ADS)

Haris, A.; Yustiawan, R.; Riyanto, A.; Ramadian, R.

2017-07-01

Pematang Brownshale is the lake sediment, which is proven as the main source rock in Malacca Strait Area. So far Brownshale is only considered as source rock, but the well data show intercalated sand layers encountered within the Pematang Brownshale, where several downhole tests proved this series as a potential hydrocarbon reservoir. Pematang formation is a syn-rift sequent deposited in Malacca Strait following the opening of central Sumatra basin during a late cretaceous to early Oligocene, which is proven as potential source rock and reservoir. The aim of the study is to identify the distribution of sandstone reservoir in Pematang Brownshale using spectral attributes. These works were carried out by integrating log data analysis and frequency maps extracted from spectral attributes Continuous Wavelet Transform (CWT). All these data are used to delineate reservoir distribution in Pematang Brownshale. Based on CWT analysis the anomalies are only visible on the frequency of I5 and I0 Hz maps, which are categorized as low frequencies. Low-frequency shadow anomaly is commonly used as an indication of the presence of hydrocarbons. The distribution of these anomalies is covering an area of approximately 3840.66 acres or equal to I554.25 sq. km, where the low-frequency pattern is interpreted as a deltaic lacustrine feature. By considering the Pematang Brown Shale of Malacca Strait area as a potential reservoir, it would open new play to another basin that has similar characteristics.

Source apportionment of volatile organic compounds measured near a cold heavy oil production area

NASA Astrophysics Data System (ADS)

Aklilu, Yayne-abeba; Cho, Sunny; Zhang, Qianyu; Taylor, Emily

2018-07-01

This study investigated sources of volatile organic compounds (VOCs) observed during periods of elevated hydrocarbon concentrations adjacent to a cold heavy oil extraction area in Alberta, Canada. Elevated total hydrocarbon (THC) concentrations were observed during the early morning hours and were associated with meteorological conditions indicative of gravitational drainage flows. THC concentrations were higher during the colder months, an occurrence likely promoted by a lower mixing height. On the other hand, other VOCs had higher concentrations in the summer; this is likely due to increased evaporation and atmospheric chemistry during the summer months. Of all investigated VOC compounds, alkanes contributed the greatest in all seasons. A source apportionment method, positive matrix factorization (PMF), was used to identify the potential contribution of various sources to the observed VOC concentrations. A total of five factors were apportioned including Benzene/Hexane, Oil Evaporative, Toluene/Xylene, Acetone and Assorted Local/Regional Air Masses. Three of the five factors (i.e., Benzene/Hexane, Oil Evaporative, and Toluene/Xylene), formed 27% of the reconstructed and unassigned concentration and are likely associated with emissions from heavy oil extraction. The three factors associated with emissions were comparable to the available emission inventory for the area. Potential sources include solution gas venting, combustion exhaust and fugitive emissions from extraction process additives. The remaining two factors (i.e., Acetone and Assorted Local/Regional Air Mass), comprised 49% of the reconstructed and unassigned concentration and contain key VOCs associated with atmospheric chemistry or the local/regional air mass such as acetone, carbonyl sulphide, Freon-11 and butane.

Groundwater monitoring plan for the Missouri River alluvial aquifer in the vicinity of the City of Independence, Missouri, well field

USGS Publications Warehouse

Wilkison, Donald H.

2012-01-01

Source contributions to monitoring and supply wells, contributing recharge areas, groundwater travel times, and current (2012) understanding of alluvial water quality were used to develop a groundwater monitoring plan for the Missouri River alluvial aquifer in the vicinity of the City of Independence, Missouri well field. The plan was designed to evaluate long-term alluvial water quality and assess potential changes in, and threats to, well-field water quality. Source contributions were determined from an existing groundwater flow model in conjunction with particle-tracking analysis and verified with water-quality data collected from 1997 through 2010 from a network of 68 monitoring wells. Three conjunctive factors - well-field pumpage, Missouri River discharge, and aquifer recharge - largely determined groundwater flow and, therefore, source contributions. The predominant source of groundwater to most monitoring wells and supply wells is the Missouri River, and this was reflected, to some extent, in alluvial water quality. To provide an estimate of the maximum potential lead time available for remedial action, monitoring wells where groundwater travel times from the contributing recharge areas are less than 2 years and predominately singular sources (such as the Missouri River or the land surface) were selected for annual sampling. The sample interval of the remaining wells, which have varying travel times and intermediate mixtures of river and land-surface contributions, were staggered on a 2-, 3-, or 4-year rotation. This was done to provide data from similar contributing areas and account for inherent aquifer variability yet minimize sample redundancy.

Pollution characteristics, risk assessment, and source apportionment of heavy metals in road dust in Beijing, China.

PubMed

Men, Cong; Liu, Ruimin; Xu, Fei; Wang, Qingrui; Guo, Lijia; Shen, Zhenyao

2018-01-15

To analyze the spatial distribution patterns, risks, and sources of heavy metals (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Fe), 36 road dust samples were collected from an urbanized area of Beijing in June 2016. The mean concentration of most metals, except As and Mn, exceeded their corresponding background values, with the mean concentration of Cd being 8 times that of its background. Spatially, for most heavy metals, except As and Mn, the high concentration areas were mainly within the 5th ring road, especially the northern area. The geo-accumulation index of Cd and Cu indicated moderate contamination at many sites. The entire study area was prone to potential ecological risks, with higher risks within the 4th ring road. Cd caused high potential ecological risk at most sites. According to the health risk assessment results, the non-carcinogenic risks that human beings suffered from heavy metals were insignificant. However, the carcinogenic risks due to Ni and Cr exceeded the acceptable level. Based on the source apportionment using positive matrix factorization, four factors were defined for the heavy metals. Factor 1, which was traffic-related exhaust, accounted for 34.47% of the concentration of heavy metals. The contributions of Factors 2 and 3 were approximately 25% each. Factor 2 was potentially related to coal combustion, while Factor 3 could be related to the manufacture and use of metal components. Factor 4, which could be related to the use of pesticides, fertilizers, and medical devices, accounted for 14.88%, which was the lowest. Copyright © 2017 Elsevier B.V. All rights reserved.

Heavy metals in the gold mine soil of the upstream area of a metropolitan drinking water source.

PubMed

Ding, Huaijian; Ji, Hongbing; Tang, Lei; Zhang, Aixing; Guo, Xinyue; Li, Cai; Gao, Yang; Briki, Mergem

2016-02-01

Pinggu District is adjacent to the county of Miyun, which contains the largest drinking water source of Beijing (Miyun Reservoir). The Wanzhuang gold field and tailing deposits are located in Pinggu, threatening Beijing's drinking water security. In this study, soil samples were collected from the surface of the mining area and the tailings piles and analyzed for physical and chemical properties, as well as heavy metal contents and particle size fraction to study the relationship between degree of pollution degree and particle size. Most metal concentrations in the gold mine soil samples exceeded the background levels in Beijing. The spatial distribution of As, Cd, Cu, Pb, and Zn was the same, while that of Cr and Ni was relatively similar. Trace element concentrations increased in larger particles, decreased in the 50-74 μm size fraction, and were lowest in the <2 μm size fraction. Multivariate analysis showed that Cu, Cd, Zn, and Pb originated from anthropogenic sources, while Cr, Ni, and Sc were of natural origin. The geo-accumulation index indicated serious Pb, As, and Cd pollution, but moderate to no Ni, Cr, and Hg pollution. The Tucker 3 model revealed three factors for particle fractions, metals, and samples. There were two factors in model A and three factors for both the metals and samples (models B and C, respectively). The potential ecological risk index shows that most of the study areas have very high potential ecological risk, a small portion has high potential ecological risk, and only a few sampling points on the perimeter have moderate ecological risk, with higher risk closer to the mining area.

Predicting S2S in Deep Time Sedimentary Systems and Implications for Petroleum Systems

NASA Astrophysics Data System (ADS)

Bhattacharya, J.

2013-12-01

The source to sink concept is focused on quantification of the various components of siliciclastic sedimentary systems from initial source areas, through the dispersal system, and deposition within a number of potential ultimate sedimentary sinks. Sequence stratigraphy shows that depositional system are linked through time and show distinctively predictable 3D stratigraphic organization, which can be related to cycles of relative changes in accommodation and sediment supply. For example, erosion and formation of incised fluvial valleys generally occur during periods of falling base level with lowstand reservoir deposits favored in more basin distal settings (e.g. deepwater fans), whereas during highstands of sea level, significantly more sediment may be sequestered in the non-marine realm and more distal environments may favor deposition of slowly-deposited condensed sections, which may make excellent hydrocarbon source rocks. Only more recently have attempts been made to quantify the size and scaling relationships of the ultimate source areas on the basis of analysis of ancient depositional systems, and the use of these scaling relationships to predict the sixe of linked depositional systems along the S2S tract. The maximum size of depositional systems, such as rivers, deltas, and submarine fans, is significantly controlled by the area, relief, and climate regime of the source area, which in turn may linked to the plate tectonic and paleogeographic setting. Classic provenance studies, and more recent use of detrital zircons, provide critical information about source-areas, and may help place limits on the size and relief of a drainage basin. Provenance studies may also provide key information about rates of exhumation of source areas and the link to the tectonic setting, Examination of ancient river systems in the rock record, and especially the largest trunk rivers, which are typically within incised valleys, can also be used to estimate paleodischarge, which in turn can be linked to the drainage basin to make estimates about the size and sale of the source area. The best estimates can be made in basins with well-constrained data that allow details of cross-sectional or plan-view channel-architecture to be determined, such as extensive outcrops, or abundant subsurface data, and especially where higher resolution 3D seismic data are available. Paleodischarge estimates of lowstand Quaternary-age continental-scale ancient rivers from passive continental margins, using seismic data, are orders-of-magnitude higher (1000's of cumecs) than smaller-scale Cretaceous lowstand systems that drained into the Western-Interior Seaway of North America (100s of cumecs). Paleodischarge of rivers can also be estimated independently by integrating estimates of drainage basin area and paleoclimate. These can be compared with paleodischarge estimates based on the river deposits themselves. The integration of paleodischarge estimates with more sophisticated provenance analysis should enable improved use of the sedimentary record to make estimates about the entire S2S system, as opposed to primarily the depositional component. A more quantitative approach to estimating the scale of sedimentary systems, and especially in the context of source areas, also puts constraints on the size and scale of potential hydrocarbon reservoirs and thus has economic value.

Modelling mass movement susceptibility for Alpine infrastructure in the Karavank Mountains (Austria/Slovenia)

NASA Astrophysics Data System (ADS)

Bauer, C.; Kern, K.; Lieb, G. K.

2012-12-01

The aim of this study is the generation of indicative susceptibility maps on a regional scale that can be used as a decision support tool for land use management (i.e. risk potential on alpine infrastructure). The study in particular focuses on geomorphological processes (rockfall and debris flows in unconsolidated rock) that reshape the land surface by erosion, transport and deposition. When interacting with human activity (e.g. road, alpine trails) such naturally occurring processes can quickly become natural hazards. The study area is located in the Karavank Mountains, a border region between Austria and Slovenia, and covers approx. 200 sq km with maximum altitudes above 2.000 m a.s.l. (Hochstuhl: 2.237 m a.s.l.). The Karavanks form an east-west striking mountain chain (approx. 120 km total length) of the southeastern Alps that consists mainly of thick Triassic carbonate sequences and, with less extent, Paleozoic carbonate rocks crystalline rocks. The mountain chain is separated into the Northern Karavanks and the Southern Karavanks by a structural boundary (Periadriatic Line). In addition, the area is known for extreme weather events due to Adriatic cyclones with daily accumulated precipitation of more than 200 mm that regularly trigger hazardous and torrential processes like rockfall events and debris flows. To assess the triggering factors and trajectories, two different disposition and process models (one for rockfall and one for debris flow, respectively) were developed. The information about potential source areas was obtained by combining various types of information (e.g. DTM derivatives, geotechnical units, vegetation). Threshold slope values for potential rockfall source areas were attributed to different lithological units according to field observations. The defined threshold slope angles cover values from 42° in Triassic carbonates up to 46° in massive crystalline rocks. For debris flows areas with a slope inclination < 20° as well as areas with dense vegetation were excluded as potential source areas. In the next step, the rockfall runout zones were estimated empirically using the cone method. This model is based on the idea that an individual falling rock can reach any place in the area situated inside a cone of given aperture. In contrast, for modelling debris flows, a multiple flow directions method was used to calculate potential pathways and velocities. The method is implemented as a random walk in conjunction with a Monte Carlo approach (using 1000 iterations). Both models were calibrated with field observation data (e.g. GPS measurements) and in addition, model results were validated with high resolution aerial photographs. By overlaying the modelling results with road and trail network information, susceptibility maps were created. These maps clearly show that large parts of the existing Alpine infrastructure are potentially affected by the modelled processes. Therefore, the resulting susceptibility maps provide as a useful tool to indicate areas prone to rockfall and debris flow as well as for the maintenance of the road and trail networks.

Ambient volatile organic compounds (VOCs) in Calgary, Alberta: Sources and screening health risk assessment.

PubMed

Bari, Md Aynul; Kindzierski, Warren B

2018-08-01

Exposure to ambient volatile organic compound (VOCs) in urban areas is of interest because of their potential chronic and acute adverse effects to public health. Limited information is available about VOC sources in urban areas in Canada. An investigation of ambient VOCs levels, their potential sources and associated risks to public health was undertaken for the urban core of Alberta's largest city (downtown Calgary) for the period 2010-2015. Twenty-four hour arithmetic and geometric mean concentrations of total VOCs were 42μg/m 3 and 39μg/m 3 , respectively and ranged from 16 to 160μg/m 3 , with winter levels about two-fold higher than summer. Alkanes (58%) were the most dominant compounds followed by halogenated VOCs (22%) and aromatics (11%). Mean and maximum 24h ambient concentrations of selected VOCs of public health concern were below chronic and acute health risk screening criteria of the United States regulatory agencies and a cancer screening benchmark used in Alberta equivalent to 1 in 100,000 lifetime risk. The Positive matrix factorization (PMF) model revealed nine VOC sources at downtown Calgary, where oil/natural gas extraction/combustion (26%), fuel combustion (20%), traffic sources including gasoline exhaust, diesel exhaust, mixed fugitive emissions (10-15%), and industrial coatings/solvents (12%) were predominant. Other sources included dry cleaning (3.3%), biogenic (3.5%) and a background source (18%). Source-specific health risk values were also estimated. Estimated cancer risks for all sources were below the Alberta cancer screening benchmark, and estimated non-cancer risks for all sources were well below a safe level. Copyright © 2018 Elsevier B.V. All rights reserved.

WEST AND EAST PALISADES ROADLESS AREAS, IDAHO AND WYOMING.

USGS Publications Warehouse

Oriel, Steven S.; Benham, John R.

1984-01-01

Studies of the West and East Palisades Roadless Areas, which lie within the Idaho-Wyoming thrust belt, document structures, reservoir formations, source beds, and thermal maturities comparable to those in producing oil and gas field farther south in the belt. Therefore, the areas are highly favorable for the occurrence of oil and gas. Phosphate beds of appropriate grade within the roadless areas are thinner and less accessible than those being mined from higher thrust sheets to the southwest; however, they contain 98 million tons of inferred phosphate rock resources in areas of substantiated phosphate resource potential. Sparsely distributed thin coal seams occur in the roadless areas. Although moderately pure limestone is present, it is available from other sources closer to markets. Geochemical anomalies from stream-sediment and rock samples for silver, copper, molydenum, and lead occur in the roadless areas but they offer little promise for the occurrence of metallic mineral resources. A possible geothermal resource is unproven, despite thermal phenomena at nearby sites.

Source apportionment of fine particulate matter measured in an industrialized coastal urban area of South Texas

NASA Astrophysics Data System (ADS)

Karnae, Saritha; John, Kuruvilla

2011-07-01

Corpus Christi is a growing industrialized urban airshed in South Texas impacted by local emissions and regional transport of fine particulate matter (PM 2.5). Positive matrix factorization (PMF2) technique was used to evaluate particulate matter pollution in the urban airshed by estimating the types of sources and its corresponding mass contributions affecting the measured ambient PM 2.5 levels. Fine particulate matter concentrations by species measured during July 2003 through December 2008 at a PM 2.5 speciation site were used in this study. PMF2 identified eight source categories, of which secondary sulfates were the dominant source category accounting for 30.4% of the apportioned mass. The other sources identified included aged sea salt (18.5%), biomass burns (12.7%), crustal dust (10.1%), traffic (9.7%), fresh sea salt (8.1%), industrial sources (6%), and a co-mingled source of oil combustion & diesel emissions (4.6%). The apportioned PM mass showed distinct seasonal variability between source categories. The PM levels in Corpus Christi were affected by biomass burns in Mexico and Central America during April and May, sub-Saharan dust storms from Africa during the summer months, and a continental haze episode during August and September with significant transport from the highly industrialized areas of Texas and the neighboring states. Potential source contribution function (PSCF) analysis was performed and it identified source regions and the influence of long-range transport of fine particulate matter affecting this urban area.

Sources and yields of dissolved carbon in northern Wisconsin stream catchments with differing amounts of Peatland

USGS Publications Warehouse

Elder, J.F.; Rybicki, N.B.; Carter, V.; Weintraub, V.

2000-01-01

In five tributary streams (four inflowing and one outflowing) of 1600-ha Trout Lake in northern Wisconsin, USA, we examined factors that can affect the magnitude of stream flow and transport of dissolved organic and inorganic carbon (DOC and DIC) through the streams to the lake. One catchment, the Allequash Creek basin, was investigated in more detail to describe the dynamics of carbon flow and to identify potential carbon sources. Stream flows and carbon loads showed little or no relation to surface-water catchment area. They were more closely related to ground-water watershed area because ground-water discharge, from both local and regional sources, is a major contributor to the hydrologic budgets of these catchments. An important factor in determining carbon influx to the stream is the area of peatland in the catchment. Peatland porewaters contain DOC concentrations up to 40 mg l-1 and are a significant potential carbon source. Ground-water discharge and lateral flow through peat are the suspected mechanisms for transport of that carbon to the streams. Carbon and nitrogen isotopes suggested that the sources of DOC in Allequash Creek above Allequash Lake were wetland vegetation and peat and that the sources below Allequash Lake were filamentous algae and wild rice. Catchments with high proportions of peatland, including the Allequash Creek catchment, tended to have elevated DOC loads in outflowing stream water. Respiration and carbon mineralization in lakes within the system tend to produce low DOC and low DOC/DIC in lake outflows, especially at Trout Lake. In Allequash Lake, however, the shallow peat island and vegetation-filled west end were sources of DOC. Despite the vast carbon reservoir in the peatlands, carbon yields were very low in these catchments. Maximum yields were on the order of 2.5 g m-2 y-1 DOC and 5.5 g m-2 y-1 DIC. The small yields were attributable to low stream flows due to lack of significant overland runoff and very limited stream channel coverage of the total catchment area.

Concerns in Water Supply and Pollution Control: Legal, Social, and Economic.

ERIC Educational Resources Information Center

Burke, D. Barlow, Jr.; And Others

This bulletin contains three articles which focus on ground water's potential as a dependable supply source and some of the problems impeding the development of that potential. The authors' concerns are discussed from the vantage point of their areas of specialization: law, sociology, and economics. The first author states that water law abounds…

The Fermi Large Area Telescope Thrid Gamma-ray Source Catalog

NASA Astrophysics Data System (ADS)

Stephens, Thomas E.; Ballet, Jean; Burnett, Toby; Cavazzuti, Elisabetta; Digel, Seth William; Fermi LAT Collaboration

2015-01-01

We present an overview of the third Fermi Large Area Telescope source catalog (3FGL) of sources in the 100 MeV - 300 GeV range. Based on the first four years of science data from the Fermi Gamma-ray Space Telescope mission, it is the deepest yet in this energy range. Relative to the 2FGL catalog (Nolan et al. 2012, ApJS 199, 31), the 3FGL catalog incorporates twice as much data as well as a number of analysis improvements, including improved calibrations at the event reconstruction level, an updated model for Galactic diffuse gamma-ray emission, a refined procedure for source detection, and improved methods for associating LAT sources with potential counterparts at other wavelengths. The 3FGL catalog includes 3033 sources, with source location regions, spectral properties, and monthly light curves for each. For approximately one-third of the sources we have not found counterparts at other wavelengths. More than 1100 of the identified or associated sources are active galaxies of the blazar class; several other classes of non-blazar active galaxies are also represented in the 3FGL. Pulsars represent the largest Galactic source class. From source counts of Galactic sources we estimate the contribution of unresolved sources to the Galactic diffuse emission.

Modeled Sources, Transport, and Accumulation of Dissolved Solids in Water Resources of the Southwestern United States.

PubMed

Anning, David W

2011-10-01

Information on important source areas for dissolved solids in streams of the southwestern United States, the relative share of deliveries of dissolved solids to streams from natural and human sources, and the potential for salt accumulation in soil or groundwater was developed using a SPAtially Referenced Regressions On Watershed attributes model. Predicted area-normalized reach-catchment delivery rates of dissolved solids to streams ranged from <10 (kg/year)/km(2) for catchments with little or no natural or human-related solute sources in them to 563,000 (kg/year)/km(2) for catchments that were almost entirely cultivated land. For the region as a whole, geologic units contributed 44% of the dissolved-solids deliveries to streams and the remaining 56% of the deliveries came from the release of solutes through irrigation of cultivated and pasture lands, which comprise only 2.5% of the land area. Dissolved-solids accumulation is manifested as precipitated salts in the soil or underlying sediments, and (or) dissolved salts in soil-pore or sediment-pore water, or groundwater, and therefore represents a potential for aquifer contamination. Accumulation rates were <10,000 (kg/year)/km(2) for many hydrologic accounting units (large river basins), but were more than 40,000 (kg/year)/km(2) for the Middle Gila, Lower Gila-Agua Fria, Lower Gila, Lower Bear, Great Salt Lake accounting units, and 247,000 (kg/year)/km(2) for the Salton Sea accounting unit.

Modeled Sources, Transport, and Accumulation of Dissolved Solids in Water Resources of the Southwestern United States1

PubMed Central

Anning, David W

2011-01-01

Abstract Information on important source areas for dissolved solids in streams of the southwestern United States, the relative share of deliveries of dissolved solids to streams from natural and human sources, and the potential for salt accumulation in soil or groundwater was developed using a SPAtially Referenced Regressions On Watershed attributes model. Predicted area-normalized reach-catchment delivery rates of dissolved solids to streams ranged from <10 (kg/year)/km2 for catchments with little or no natural or human-related solute sources in them to 563,000 (kg/year)/km2 for catchments that were almost entirely cultivated land. For the region as a whole, geologic units contributed 44% of the dissolved-solids deliveries to streams and the remaining 56% of the deliveries came from the release of solutes through irrigation of cultivated and pasture lands, which comprise only 2.5% of the land area. Dissolved-solids accumulation is manifested as precipitated salts in the soil or underlying sediments, and (or) dissolved salts in soil-pore or sediment-pore water, or groundwater, and therefore represents a potential for aquifer contamination. Accumulation rates were <10,000 (kg/year)/km2 for many hydrologic accounting units (large river basins), but were more than 40,000 (kg/year)/km2 for the Middle Gila, Lower Gila-Agua Fria, Lower Gila, Lower Bear, Great Salt Lake accounting units, and 247,000 (kg/year)/km2 for the Salton Sea accounting unit. PMID:22457583

Validation of a novel air toxic risk model with air monitoring.

PubMed

Pratt, Gregory C; Dymond, Mary; Ellickson, Kristie; Thé, Jesse

2012-01-01

Three modeling systems were used to estimate human health risks from air pollution: two versions of MNRiskS (for Minnesota Risk Screening), and the USEPA National Air Toxics Assessment (NATA). MNRiskS is a unique cumulative risk modeling system used to assess risks from multiple air toxics, sources, and pathways on a local to a state-wide scale. In addition, ambient outdoor air monitoring data were available for estimation of risks and comparison with the modeled estimates of air concentrations. Highest air concentrations and estimated risks were generally found in the Minneapolis-St. Paul metropolitan area and lowest risks in undeveloped rural areas. Emissions from mobile and area (nonpoint) sources created greater estimated risks than emissions from point sources. Highest cancer risks were via ingestion pathway exposures to dioxins and related compounds. Diesel particles, acrolein, and formaldehyde created the highest estimated inhalation health impacts. Model-estimated air concentrations were generally highest for NATA and lowest for the AERMOD version of MNRiskS. This validation study showed reasonable agreement between available measurements and model predictions, although results varied among pollutants, and predictions were often lower than measurements. The results increased confidence in identifying pollutants, pathways, geographic areas, sources, and receptors of potential concern, and thus provide a basis for informing pollution reduction strategies and focusing efforts on specific pollutants (diesel particles, acrolein, and formaldehyde), geographic areas (urban centers), and source categories (nonpoint sources). The results heighten concerns about risks from food chain exposures to dioxins and PAHs. Risk estimates were sensitive to variations in methodologies for treating emissions, dispersion, deposition, exposure, and toxicity. © 2011 Society for Risk Analysis.

Source apportionment and health risk assessment of potentially toxic elements in road dust from urban industrial areas of Ahvaz megacity, Iran.

PubMed

Najmeddin, Ali; Keshavarzi, Behnam; Moore, Farid; Lahijanzadeh, Ahmadreza

2017-10-28

This study investigates the occurrence and spatial distribution of potentially toxic elements (PTEs) (Hg, Cd, Cu, Mo, Pb, Zn, Ni, Co, Cr, Al, Fe, Mn, V and Sb) in 67 road dust samples collected from urban industrial areas in Ahvaz megacity, southwest of Iran. Geochemical methods, multivariate statistics, geostatistics and health risk assessment model were adopted to study the spatial pollution pattern and to identify the priority pollutants, regions of concern and sources of the studied PTEs. Also, receptor positive matrix factorization model was employed to assess pollution sources. Compared to the local background, the median enrichment factor values revealed the following order: Sb > Pb > Hg > Zn > Cu > V > Fe > Mo > Cd > Mn > Cr ≈ Co ≈ Al ≈ Ni. Statistical results show that a significant difference exists between concentrations of Mo, Cu, Pb, Zn, Fe, Sb, V and Hg in different regions (univariate analysis, Kruskal-Wallis test p < 0.05), indicating the existence of highly contaminated spots. Integrated source identification coupled with positive matrix factorization model revealed that traffic-related emissions (43.5%) and steel industries (26.4%) were first two sources of PTEs in road dust, followed by natural sources (22.6%) and pipe and oil processing companies (7.5%). The arithmetic mean of pollution load index (PLI) values for high traffic sector (1.92) is greater than industrial (1.80) and residential areas (1.25). Also, the results show that ecological risk values for Hg and Pb in 41.8 and 9% of total dust samples are higher than 80, indicating their considerable or higher potential ecological risk. The health risk assessment model showed that ingestion of dust particles contributed more than 83% of the overall non-carcinogenic risk. For both residential and industrial scenarios, Hg and Pb had the highest risk values, whereas Mo has the lowest value.

The mineral resource potential of the Wadi Habawnah and Najran quadrangles, sheets 17/44A and 17/44C, Kingdom of Saudi Arabia

USGS Publications Warehouse

Fenton, Michael D.

1983-01-01

The metallic resource potential of the Wadi Habawnah and Najran quadrangles in the southern Precambrian Arabian Shield has been determined primarily by reconnaissance rock geochemistry, limited wadi-sediment and colluvium geochemistry, and gossanous and ferruginous outcrop geochemistry. These surveys were guided by geological information acquired during previous reconnaissance mapping. Locally anomalous areas in alkalic and calc-alkalic granitic terrane are possible sources of niobium-zirconiumthorium-fluorite, tin-tungsten, and copper-molybdenum, although the potential of these areas does not appear to be outstanding. The reconnaissance geochemistry of the layered volcanic terrane and the geochemistry of gossanous and ferruginous outcrops indicate that the potential for stratiform base metal sulfide deposits is low.

Timing and synchrony of births in bighorn sheep: implications for reintroduction and conservation

USGS Publications Warehouse

Whiting, Jericho C.; Olson, Daniel D.; Shannon, Justin M.; Bowyer, R. Terry; Klaver, Robert W.; Flinders, Jerran T.

2012-01-01

Implications: Consideration should be given to the adjustment of timing and synchrony of births when reintroducing bighorns, especially when animals are released into different ecoregions. Also, biologists should select release sites that are ecologically similar to source areas, thereby reducing potential negative effects of animals adjusting timing and synchrony of births to environmental conditions of restoration areas.

Assessing field vulnerability to phosphorus loss in Beijing agricultural area using Revised Field Phosphorus Ranking Scheme.

PubMed

Li, Qi; Chen, Li-ding; Qi, Xin; Zhang, Xin-yu; Ma, Yan; Fu, Bo-jie

2007-01-01

Guanting Reservoir, one of the drinking water supply sources of Beijing, suffers from water eutrophication. It is mainly supplied by Guishui River. Thus, to investigate the reasons of phosphorus (P) loss and improve the P management strategies in Guishui River watershed are important for the safety of drinking water in this region. In this study, a Revised Field P Ranking Scheme (PRS) was developed to reflect the field vulnerability of P loss at the field scale based on the Field PRS. In this new scheme, six factors are included, and each one was assigned a relative weight and a determination method. The affecting factors were classified into transport factors and source factors, and, the standards of environmental quality on surface water and soil erosion classification and degradation of the China were used in this scheme. By the new scheme, thirty-four fields in the Guishui River were categorized as "low", "medium" or "high" potential for P loss into the runoff. The results showed that the P loss risks of orchard and vegetable fields were higher than that of corn and soybean fields. The source factors were the main factors to affect P loss from the study area. In the study area, controlling P input and improving P usage efficiency are critical to decrease P loss. Based on the results, it was suggested that more attention should be paid on the fields of vegetable and orchard since they have extremely high usage rate of P and high soil test of P. Compared with P surplus by field measurements, the Revised Field PRS was more suitable for reflecting the characteristics of fields, and had higher potential capacity to identify critical source areas of P loss than PRS.

The Run-Up of Subduction Zones

NASA Astrophysics Data System (ADS)

Riquelme, S.; Bravo, F. J.; Fuentes, M.; Matias, M.; Medina, M.

2016-12-01

Large earthquakes in subduction zones are liable to produce tsunamis that can cause destruction and fatalities. The Run-up is a geophysical parameter that quantifies damage and if critical facilities or population are exposed to. Here we use the coupling for certain subduction regions measured by different techniques (Potency and GPS observations) to define areas where large earthquakes can occur. Taking the slab 1.0 from the United States Geological Survey (USGS), we can define the geometry of the area including its tsunamigenic potential. By using stochastic earthquakes sources for each area with its maximum tsunamigenic potential, we calculate the numerical and analytical run-up for each case. Then, we perform a statistical analysis and calculate the envelope for both methods. Furthermore, we build an index of risk using: the closest slope to the shore in a piecewise linear approach (last slopecriteria) and the outputsfrom tsunami modeling. Results show that there are areas prone to produce higher run-up than others based on the size of the earthquake, geometrical constraints of the source, tectonic setting and the coast last slope. Based on these results, there are zones that have low risk index which can define escape routes or secure coastal areas for tsunami early warning, urban and planning purposes when detailed data is available.

Bioaccumulation of selenium from natural geologic sources in western states and its potential consequences

USGS Publications Warehouse

Presser, T.S.; Sylvester, M.A.; Low, W.H.

1994-01-01

Ecological impacts of water-quality problems have developed in the western United States resulting from the disposal of seleniferous agricultural wastewater in wetland areas. Overt effects of selenium toxicosis occurred at five areas where deformities of wild aquatic birds were similar to those first observed at Kesterson National Wildlife Refuge in the west-central San Joaquin Valley of California. These areas are: Tulare Lake Bed Area, California, Middle Green River Basin, Utah, Kandrick Reclamation Project Area, Wyoming, Sun River Basin, Montana, and Stillwater Wildlife Management Area, Nevada. Potential for ecological damage is indicated at six more sites in Oregon, Colorado, the Colorado/Kansas border, and South Dakota out of 16 areas in 11 states where biological tissue data were collected. This conclusion is based on the fact that selenium bioaccumulated in bird livers to median levels that had exceeded or were in the range associated with adverse reproductive effects. Selenium concentrations in samples of fish and bird eggs support these conclusions at a majority of these areas. Reason for concern is also given for the lower Colorado River Valley, although this is not exclusively a conclusion from these reconnaissance data. Biogeochemical conditions and the extent of selenium contamination of water, bottom sediment, and biota from which this assessment was made are given here. In a companion paper, the biogeochemical pathway postulated for selenium contamination to take place from natural geologic sources to aquatic wildlife is defined.

Bioaccumulation of selenium from natural geologic sources in western states and its potential consequences

NASA Astrophysics Data System (ADS)

Presser, Theresa S.; Sylvester, Marc A.; Low, Walton H.

1994-05-01

Ecological impacts of water-quality problems have developed in the western United States resulting from the disposal of seleniferous agricultural wastewater in wetland areas. Overt effects of selenium toxicosis occurred at five areas where deformities of wild aquatic birds were similar to those first observed at Kesterson National Wildlife Refuge in the west-central San Joaquin Valley of California. These areas are: Tulare Lake Bed Area, California, Middle Green River Basin, Utah, Kendrick Reclamation Project Area, Wyoming, Sun River Basin, Montana, and Stillwater Wildlife Management Area, Nevada. Potential for ecological damage is indicated at six more sites in Oregon, Colorado, the Colorado/Kansas border, and South Dakota out of 16 areas in 11 states where biological tissue data were collected. This conclusion is based on the fact that selenium bioaccumulated in bird livers to median levels that had exceeded or were in the range associated with adverse reproductive effects. Selenium concentrations in samples of fish and bird eggs support these conclusions at a majority of these areas. Reason for concern is also given for the lower Colorado River Valley, although this is not exclusively a conclusion from these reconnaissance data. Biogeochemical conditions and the extent of selenium contamination of water, bottom sediment, and biota from which this assessment was made are given here. In a companion paper, the biogeochemical pathway postulated for selenium contamination to take place from natural geologic sources to aquatic wildlife is defined.

Characterizing the detectability of emission signals from a North Korean nuclear detonation

DOE PAGES

Werth, David; Buckley, Robert

2017-02-01

Here, the detectability of emission sources, defined by a low-level of mixing with other sources, was estimated for various locations surrounding the Sea of Japan, including a site within North Korea. A high-resolution meteorological model coupled to a dispersion model was used to simulate plume dynamics for four periods, and two metrics of airborne plume mixing were calculated for each source. While emissions from several known sources in this area tended to blend with others while dispersing downwind, the North Korean plume often remained relatively distinct, thereby making it potentially easier to unambiguously ‘backtrack’ it to its source.

Evaluation damage threshold of optical thin-film using an amplified spontaneous emission source

NASA Astrophysics Data System (ADS)

Zhou, Qiong; Sun, Mingying; Zhang, Zhixiang; Yao, Yudong; Peng, Yujie; Liu, Dean; Zhu, Jianqiang

2014-10-01

An accurate evaluation method with an amplified spontaneous emission (ASE) as the irradiation source has been developed for testing thin-film damage threshold. The partial coherence of the ASE source results in a very smooth beam profile in the near-field and a uniform intensity distribution of the focal spot in the far-field. ASE is generated by an Nd: glass rod amplifier in SG-II high power laser facility, with pulse duration of 9 ns and spectral width (FWHM) of 1 nm. The damage threshold of the TiO2 high reflection film is 14.4J/cm2 using ASE as the irradiation source, about twice of 7.4 J/cm2 that tested by a laser source with the same pulse duration and central wavelength. The damage area induced by ASE is small with small-scale desquamation and a few pits, corresponding to the defect distribution of samples. Large area desquamation is observed in the area damaged by laser, as the main reason that the non-uniformity of the laser light. The ASE damage threshold leads to more accurate evaluations of the samples damage probability by reducing the influence of hot spots in the irradiation beam. Furthermore, the ASE source has a great potential in the detection of the defect distribution of the optical elements.

Detection and temporal variation of (60)Co in the digestive glands of the common octopus, Octopus vulgaris, in the East China Sea.

PubMed

Morita, Takami; Otosaka, Shigeyoshi; Fujimoto, Ken; Nishiuchi, Kou; Kimoto, Katsunori; Yamada, Haruya; Kasai, Hiromi; Minakawa, Masayuki; Yoshida, Katsuhiko

2010-08-01

(60)Co were detected in common octopus specimens collected in the East China Sea in 1996-2005. The source of (60)Co has remained unclear yet. Stable isotope analyses showed that there was no difference in stable Co concentrations between octopus samples with (60)Co and without (60)Co. This result showed that the stable Co in the digestive gland of octopus potentially did not include a trace amount of (60)Co and the source of (60)Co existed independently. Furthermore, investigations of octopus in other area and other species indicated that the origin of the source of (60)Co occurred locally in the restricted area in the East China Sea and not in the coastal area of Japan. Concentrations of (60)Co have annually decreased with shorter half-life than the physical half-life. This decrease tendency suggests that the sources of (60)Co were identical and were temporary dumped into the East China Sea as a solid waste. Copyright 2010 Elsevier Ltd. All rights reserved.

Chapter 1: An overview of the petroleum geology of the Arctic

USGS Publications Warehouse

Spencer, A.M.; Embry, A.F.; Gautier, D.L.; Stoupakova, A.V.; Sorensen, K.

2011-01-01

Nine main petroleum provinces containing recoverable resources totalling 61 Bbbl liquids + 269 Bbbloe of gas are known in the Arctic. The three best known major provinces are: West Siberia-South Kara, Arctic Alaska and Timan-Pechora. They have been sourced principally from, respectively, Upper Jurassic, Triassic and Devonian marine source rocks and their hydrocarbons are reservoired principally in Cretaceous sandstones, Triassic sandstones and Palaeozoic carbonates. The remaining six provinces except for the Upper Cretaceous-Palaeogene petroleum system in the Mackenzie Delta have predominantly Mesozoic sources and Jurassic reservoirs. There are discoveries in 15% of the total area of sedimentary basins (c. 8 ?? 106 km2), dry wells in 10% of the area, seismic but no wells in 50% and no seismic in 25%. The United States Geological Survey estimate yet-to-find resources to total 90 Bbbl liquids + 279 Bbbloe gas, with four regions - South Kara Sea, Alaska, East Barents Sea, East Greenland - dominating. Russian estimates of South Kara Sea and East Barents Sea are equally positive. The large potential reflects primarily the large undrilled areas, thick basins and widespread source rocks. ?? 2011 The Geological Society of London.

Retrofitting impervious urban infrastructure with green technology for rainfall-runoff restoration, indirect reuse and pollution load reduction.

PubMed

Sansalone, John; Raje, Saurabh; Kertesz, Ruben; Maccarone, Kerrilynn; Seltzer, Karl; Siminari, Michele; Simms, Peter; Wood, Brandon

2013-12-01

The built environs alter hydrology and water resource chemistry. Florida is subject to nutrient criteria and is promulgating "no-net-load-increase" criteria for runoff and constituents (nutrients and particulate matter, PM). With such criteria, green infrastructure, hydrologic restoration, indirect reuse and source control are potential design solutions. The study simulates runoff and constituent load control through urban source area re-design to provide long-term "no-net-load-increases". A long-term continuous simulation of pre- and post-development response for an existing surface parking facility is quantified. Retrofits include a biofiltration area reactor (BAR) for hydrologic and denitrification control. A linear infiltration reactor (LIR) of cementitious permeable pavement (CPP) provides infiltration, adsorption and filtration. Pavement cleaning provided source control. Simulation of climate and source area data indicates re-design achieves "no-net-load-increases" at lower costs compared to standard construction. The retrofit system yields lower cost per nutrient load treated compared to Best Management Practices (BMPs). Copyright © 2013 Elsevier Ltd. All rights reserved.

An novel identification method of the environmental risk sources for surface water pollution accidents in chemical industrial parks.

PubMed

Peng, Jianfeng; Song, Yonghui; Yuan, Peng; Xiao, Shuhu; Han, Lu

2013-07-01

The chemical industry is a major source of various pollution accidents. Improving the management level of risk sources for pollution accidents has become an urgent demand for most industrialized countries. In pollution accidents, the released chemicals harm the receptors to some extent depending on their sensitivity or susceptibility. Therefore, identifying the potential risk sources from such a large number of chemical enterprises has become pressingly urgent. Based on the simulation of the whole accident process, a novel and expandable identification method for risk sources causing water pollution accidents is presented. The newly developed approach, by analyzing and stimulating the whole process of a pollution accident between sources and receptors, can be applied to identify risk sources, especially on the nationwide scale. Three major types of losses, such as social, economic and ecological losses, were normalized, analyzed and used for overall consequence modeling. A specific case study area, located in a chemical industry park (CIP) along the Yangtze River in Jiangsu Province, China, was selected to test the potential of the identification method. The results showed that there were four risk sources for pollution accidents in this CIP. Aniline leakage in the HS Chemical Plant would lead to the most serious impact on the surrounding water environment. This potential accident would severely damage the ecosystem up to 3.8 km downstream of Yangtze River, and lead to pollution over a distance stretching to 73.7 km downstream. The proposed method is easily extended to the nationwide identification of potential risk sources.

Wide area methane emissions mapping with airborne IPDA lidar

NASA Astrophysics Data System (ADS)

Bartholomew, Jarett; Lyman, Philip; Weimer, Carl; Tandy, William

2017-08-01

Methane emissions from natural gas production, storage, and transportation are potential sources of greenhouse gas emissions. Methane leaks also constitute revenue loss potential from operations. Since 2013, Ball Aerospace has been developing advanced airborne sensors using integrated path differential absorption (IPDA) LIDAR instrumentation to identify methane, propane, and longer-chain alkanes in the lowest region of the atmosphere. Additional funding has come from the U.S. Department of Transportation, Pipeline and Hazardous Materials Administration (PHMSA) to upgrade instrumentation to a broader swath coverage of up to 400 meters while maintaining high spatial sampling resolution and geolocation accuracy. Wide area coverage allows efficient mapping of emissions from gathering and distribution networks, processing facilities, landfills, natural seeps, and other distributed methane sources. This paper summarizes the benefits of advanced instrumentation for aerial methane emission mapping, describes the operating characteristics and design of this upgraded IPDA instrumentation, and reviews technical challenges encountered during development and deployment.

Aerial Surveys of Endangered Whales in the Beaufort, Chukchi & Northern Bering Seas.

DTIC Science & Technology

1982-03-01

geophysical boats (in preparation). CGales, R.S., 1982. Effects of noise of offshore oil and gas operations on marine mammals - an introductory assessment...the bowheads through or near areas on the outer continental shelf of Alaska that are currently being assessed as potential sources of mineral and oil ...Federal and Joint State-Federal oil lease areas in the Beaufort Sea (Ljungblad et al, 1980; Ljungblad, 1981). This area is collectively called the Diapir

Results From a Microbial Source-Tracking Study at Villa Angela Beach, Cleveland, Ohio, 2007

USGS Publications Warehouse

Bushon, Rebecca N.; Stelzer, Erin A.; Stoeckel, Donald M.

2009-01-01

During the 2007 recreational season at Villa Angela Beach in Cleveland, Ohio, scientists with the U.S. Geological Survey (USGS) and the Northeast Ohio Regional Sewer District (NEORSD) found high Escherichia coli (E. coli) concentrations that were not easily explained by results obtained to date in ongoing investigations of recreational water quality at the beach. To help understand the sources behind these elevated E. coli concentrations, the USGS and NEORSD sampled beach-area water for Bacteroides DNA markers. Bacteroides are a group of enteric bacteria that are being used in microbial source tracking, in hope that host-associated DNA markers could be used to indicate potential sources of E. coli in the Villa Angela environment. The USGS Ohio Water Microbiology Laboratory analyzed a total of 13 source samples (sewage and waterfowl feces) and 33 beach-area water and sand samples for three Bacteroides DNA markers. This report lists the results of those analyses, along with environmental conditions at Villa Angela on the dates that samples were collected.

Integration and Utilization of Nuclear Systems on the Moon and Mars

DOE Office of Scientific and Technical Information (OSTI.GOV)

Houts, Michael G.; Schmidt, George R.; Bragg-Sitton, Shannon

2006-01-20

Over the past five decades numerous studies have identified nuclear energy as an enhancing or enabling technology for planetary surface exploration missions. This includes both radioisotope and fission sources for providing both heat and electricity. Nuclear energy sources were used to provide electricity on Apollo missions 12, 14, 15, 16, and 17, and on the Mars Viking landers. Very small nuclear energy sources were used to provide heat on the Mars Pathfinder, Spirit, and Opportunity rovers. Research has been performed at NASA MSFC to help assess potential issues associated with surface nuclear energy sources, and to generate data that couldmore » be useful to a future program. Research areas include System Integration, use of Regolith as Radiation Shielding, Waste Heat Rejection, Surface Environmental Effects on the Integrated System, Thermal Simulators, Surface System Integration / Interface / Interaction Testing, End-to-End Breadboard Development, Advanced Materials Development, Surface Energy Source Coolants, and Planetary Surface System Thermal Management and Control. This paper provides a status update on several of these research areas.« less

Numerical evaluation of longitudinal motions of Wigley hulls advancing in waves by using Bessho form translating-pulsating source Green'S function

NASA Astrophysics Data System (ADS)

Xiao, Wenbin; Dong, Wencai

2016-06-01

In the framework of 3D potential flow theory, Bessho form translating-pulsating source Green's function in frequency domain is chosen as the integral kernel in this study and hybrid source-and-dipole distribution model of the boundary element method is applied to directly solve the velocity potential for advancing ship in regular waves. Numerical characteristics of the Green function show that the contribution of local-flow components to velocity potential is concentrated at the nearby source point area and the wave component dominates the magnitude of velocity potential in the far field. Two kinds of mathematical models, with or without local-flow components taken into account, are adopted to numerically calculate the longitudinal motions of Wigley hulls, which demonstrates the applicability of translating-pulsating source Green's function method for various ship forms. In addition, the mesh analysis of discrete surface is carried out from the perspective of ship-form characteristics. The study shows that the longitudinal motion results by the simplified model are somewhat greater than the experimental data in the resonant zone, and the model can be used as an effective tool to predict ship seakeeping properties. However, translating-pulsating source Green function method is only appropriate for the qualitative analysis of motion response in waves if the ship geometrical shape fails to satisfy the slender-body assumption.

Analyses of geological and hydrodynamic controls on methane emissions experienced in a Lower Kittanning coal mine

PubMed Central

Karacan, C. Özgen; Goodman, Gerrit V.R.

2015-01-01

This paper presents a study assessing potential factors and migration paths of methane emissions experienced in a room-and-pillar mine in Lower Kittanning coal, Indiana County, Pennsylvania. Methane emissions were not excessive at idle mining areas, but significant methane was measured during coal mining and loading. Although methane concentrations in the mine did not exceed 1% limit during operation due to the presence of adequate dilution airflow, the source of methane and its migration into the mine was still a concern. In the course of this study, structural and depositional properties of the area were evaluated to assess complexity and sealing capacity of roof rocks. Composition, gas content, and permeability of Lower Kittanning coal, results of flotation tests, and geochemistry of groundwater obtained from observation boreholes were studied to understand the properties of coal and potential effects of old abandoned mines within the same area. These data were combined with the data obtained from exploration boreholes, such as depths, elevations, thicknesses, ash content, and heat value of coal. Univariate statistical and principal component analyses (PCA), as well as geostatistical simulations and co-simulations, were performed on various spatial attributes to reveal interrelationships and to establish area-wide distributions. These studies helped in analyzing groundwater quality and determining gas-in-place (GIP) of the Lower Kittanning seam. Furthermore, groundwater level and head on the Lower Kittanning coal were modeled and flow gradients within the study area were examined. Modeling results were interpreted with the structural geology of the Allegheny Group of formations above the Lower Kittanning coal to understand the potential source of gas and its migration paths. Analyses suggested that the source of methane was likely the overlying seams such as the Middle and Upper Kittanning coals and Freeport seams of the Allegheny Group. Simulated ground-water water elevations, gradients of groundwater flow, and the presence of recharge and discharge locations at very close proximity to the mine indicated that methane likely was carried with groundwater towards the mine entries. Existing fractures within the overlying strata and their orientation due to the geologic conditions of the area, and activation of slickensides between shale and sandstones due to differential compaction during mining, were interpreted as the potential flow paths. PMID:26478644

Spatial analysis and source profiling of beta-agonists and sulfonamides in Langat River basin, Malaysia.

PubMed

Sakai, Nobumitsu; Mohd Yusof, Roslan; Sapar, Marni; Yoneda, Minoru; Ali Mohd, Mustafa

2016-04-01

Beta-agonists and sulfonamides are widely used for treating both humans and livestock for bronchial and cardiac problems, infectious disease and even as growth promoters. There are concerns about their potential environmental impacts, such as producing drug resistance in bacteria. This study focused on their spatial distribution in surface water and the identification of pollution sources in the Langat River basin, which is one of the most urbanized watersheds in Malaysia. Fourteen beta-agonists and 12 sulfonamides were quantitatively analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A geographic information system (GIS) was used to visualize catchment areas of the sampling points, and source profiling was conducted to identify the pollution sources based on a correlation between a daily pollutant load of the detected contaminant and an estimated density of human or livestock population in the catchment areas. As a result, 6 compounds (salbutamol, sulfadiazine, sulfapyridine, sulfamethazine, sulfadimethoxine and sulfamethoxazole) were widely detected in mid catchment areas towards estuary. The source profiling indicated that the pollution sources of salbutamol and sulfamethoxazole were from sewage, while sulfadiazine was from effluents of cattle, goat and sheep farms. Thus, this combination method of quantitative and spatial analysis clarified the spatial distribution of these drugs and assisted for identifying the pollution sources. Copyright © 2016 Elsevier B.V. All rights reserved.

Methane baseline concentrations and sources in shallow aquifers from the shale gas-prone region of the St. Lawrence lowlands (Quebec, Canada).

PubMed

Moritz, Anja; Hélie, Jean-Francois; Pinti, Daniele L; Larocque, Marie; Barnetche, Diogo; Retailleau, Sophie; Lefebvre, René; Gélinas, Yves

2015-04-07

Hydraulic fracturing is becoming an important technique worldwide to recover hydrocarbons from unconventional sources such as shale gas. In Quebec (Canada), the Utica Shale has been identified as having unconventional gas production potential. However, there has been a moratorium on shale gas exploration since 2010. The work reported here was aimed at defining baseline concentrations of methane in shallow aquifers of the St. Lawrence Lowlands and its sources using δ(13)C methane signatures. Since this study was performed prior to large-scale fracturing activities, it provides background data prior to the eventual exploitation of shale gas through hydraulic fracturing. Groundwater was sampled from private (n = 81), municipal (n = 34), and observation (n = 15) wells between August 2012 and May 2013. Methane was detected in 80% of the wells with an average concentration of 3.8 ± 8.8 mg/L, and a range of <0.0006 to 45.9 mg/L. Methane concentrations were linked to groundwater chemistry and distance to the major faults in the studied area. The methane δ(1)(3)C signature of 19 samples was > -50‰, indicating a potential thermogenic source. Localized areas of high methane concentrations from predominantly biogenic sources were found throughout the study area. In several samples, mixing, migration, and oxidation processes likely affected the chemical and isotopic composition of the gases, making it difficult to pinpoint their origin. Energy companies should respect a safe distance from major natural faults in the bedrock when planning the localization of hydraulic fracturation activities to minimize the risk of contaminating the surrounding groundwater since natural faults are likely to be a preferential migration pathway for methane.

Impacts of urbanization on the distribution of heavy metals in soils along the Huangpu River, the drinking water source for Shanghai.

PubMed

Bai, Yang; Wang, Min; Peng, Chi; Alatalo, Juha M

2016-03-01

We investigated the horizontal and vertical distribution of heavy metals (Hg, Pb, Zn, Cu, Cd, As, Ni, and Cr) in soils in the water source protection zone for Shanghai to study the origins of these metals, their connections with urbanization, and their potential risk posed on the ecosystem. Determination of metal concentrations in 50 topsoil samples and nine soil profiles indicated that Hg, Pb, Zn, and Cu were present in significantly higher concentrations in topsoil than in deep soil layers. The spatial distributions of Hg, Pb, Zn, and Cu and contamination hotspots for these metals in the study area were similar to those near heavy industries and urban built-up areas. Emissions from automobiles resulted in increased soil concentrations of Cu, Pb, and Zn along roadsides, while high concentrations of Hg in the soil resulted from recent atmospheric deposition. Calculation of the potential ecological risk indicated that the integrative risk of these heavy metals in most areas was low, but a few sites surrounding high density of factories showed moderate risks.

Tsunamis caused by submarine slope failures along western Great Bahama Bank

PubMed Central

Schnyder, Jara S.D.; Eberli, Gregor P.; Kirby, James T.; Shi, Fengyan; Tehranirad, Babak; Mulder, Thierry; Ducassou, Emmanuelle; Hebbeln, Dierk; Wintersteller, Paul

2016-01-01

Submarine slope failures are a likely cause for tsunami generation along the East Coast of the United States. Among potential source areas for such tsunamis are submarine landslides and margin collapses of Bahamian platforms. Numerical models of past events, which have been identified using high-resolution multibeam bathymetric data, reveal possible tsunami impact on Bimini, the Florida Keys, and northern Cuba. Tsunamis caused by slope failures with terminal landslide velocity of 20 ms−1 will either dissipate while traveling through the Straits of Florida, or generate a maximum wave of 1.5 m at the Florida coast. Modeling a worst-case scenario with a calculated terminal landslide velocity generates a wave of 4.5 m height. The modeled margin collapse in southwestern Great Bahama Bank potentially has a high impact on northern Cuba, with wave heights between 3.3 to 9.5 m depending on the collapse velocity. The short distance and travel time from the source areas to densely populated coastal areas would make the Florida Keys and Miami vulnerable to such low-probability but high-impact events. PMID:27811961

Arsenic concentrations in Baltic Sea sediments close to chemical munitions dumpsites

NASA Astrophysics Data System (ADS)

Bełdowski, Jacek; Szubska, Marta; Emelyanov, Emelyan; Garnaga, Galina; Drzewińska, Anna; Bełdowska, Magdalena; Vanninen, Paula; Östin, Anders; Fabisiak, Jacek

2016-06-01

In addition to natural sources and land-originated pollution, the Baltic Sea has another anthropogenic source of arsenic in bottom sediments-arsenic-based Chemical Warfare Agents (CWA). To examine the potential usage of arsenic contents results for monitoring the leakage from chemical weapons, sediment samples were collected from officially reported and potential chemical weapon dumpsites located in the Baltic Sea, and total and inorganic arsenic concentrations were analyzed. Results showed an elevated arsenic content in dumpsite areas compared to reference areas. Correlations of arsenic with other metals and organic matter were studied to elucidate any unusual behavior of arsenic in the dumpsites. In the area of the Bornholm Deep, such behavior was observed for inorganic arsenic. It appears that in close vicinity of dumped munitions, the inorganic arsenic concentration of sediments is not correlated with either organic matter content or authigenic minerals formation, as is commonly observed elsewhere. Investigations on CWA concentrations, performed within the CHEMSEA (Chemical Munition Search and Assesment) project, allowed us to compare the results of arsenic concentrations with the occurrence of arsenic-containing CWA.

Tsunamis caused by submarine slope failures along western Great Bahama Bank

NASA Astrophysics Data System (ADS)

Schnyder, Jara S. D.; Eberli, Gregor P.; Kirby, James T.; Shi, Fengyan; Tehranirad, Babak; Mulder, Thierry; Ducassou, Emmanuelle; Hebbeln, Dierk; Wintersteller, Paul

2016-11-01

Submarine slope failures are a likely cause for tsunami generation along the East Coast of the United States. Among potential source areas for such tsunamis are submarine landslides and margin collapses of Bahamian platforms. Numerical models of past events, which have been identified using high-resolution multibeam bathymetric data, reveal possible tsunami impact on Bimini, the Florida Keys, and northern Cuba. Tsunamis caused by slope failures with terminal landslide velocity of 20 ms-1 will either dissipate while traveling through the Straits of Florida, or generate a maximum wave of 1.5 m at the Florida coast. Modeling a worst-case scenario with a calculated terminal landslide velocity generates a wave of 4.5 m height. The modeled margin collapse in southwestern Great Bahama Bank potentially has a high impact on northern Cuba, with wave heights between 3.3 to 9.5 m depending on the collapse velocity. The short distance and travel time from the source areas to densely populated coastal areas would make the Florida Keys and Miami vulnerable to such low-probability but high-impact events.

Tsunamis caused by submarine slope failures along western Great Bahama Bank.

PubMed

Schnyder, Jara S D; Eberli, Gregor P; Kirby, James T; Shi, Fengyan; Tehranirad, Babak; Mulder, Thierry; Ducassou, Emmanuelle; Hebbeln, Dierk; Wintersteller, Paul

2016-11-04

Submarine slope failures are a likely cause for tsunami generation along the East Coast of the United States. Among potential source areas for such tsunamis are submarine landslides and margin collapses of Bahamian platforms. Numerical models of past events, which have been identified using high-resolution multibeam bathymetric data, reveal possible tsunami impact on Bimini, the Florida Keys, and northern Cuba. Tsunamis caused by slope failures with terminal landslide velocity of 20 ms -1 will either dissipate while traveling through the Straits of Florida, or generate a maximum wave of 1.5 m at the Florida coast. Modeling a worst-case scenario with a calculated terminal landslide velocity generates a wave of 4.5 m height. The modeled margin collapse in southwestern Great Bahama Bank potentially has a high impact on northern Cuba, with wave heights between 3.3 to 9.5 m depending on the collapse velocity. The short distance and travel time from the source areas to densely populated coastal areas would make the Florida Keys and Miami vulnerable to such low-probability but high-impact events.

Pulpwood Chip Productions and Markets in the Lake States

Treesearch

Eugene W. Fobes

1966-01-01

As a major pulp and paper production area, the Lake States is a potential market for pulpwood chips. As a producer of solid wood products, it has a considerable potential for the production of pulpwood chips from coarse sawmill residues (slabs, edgings, and trim) and other sources. Only a small amount of the available residues, however, is now being utilized. In...

A global meta-analysis on the impact of management practices on net global warming potential and greenhouse gas intensity from cropland soils

USDA-ARS?s Scientific Manuscript database

Agricultural practices contribute significant amount of greenhouse gas (GHG) emissions, but little is known about their effects on net global warming potential (GWP) and greenhouse gas intensity (GHGI) that account for all sources and sinks of carbon dioxide emissions per unit area or crop yield. Se...

Brominated flame retardants in marine environment focused on aquaculture area: Occurrence, source and bioaccumulation.

PubMed

Gu, Seo-Yeon; Ekpeghere, Kalu Ibe; Kim, Hee-Young; Lee, In-Seok; Kim, Da-Hye; Choo, Gyojin; Oh, Jeong-Eun

2017-12-01

Brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A (TBBPA), and hexabromocyclododecanes (HBCDs), were investigated in bivalve (i.e., oyster (Crassostrea gigas) and mussel (Mytilus coruscus)), sediment, and seawater samples collected from aquaculture areas in South Korea to identify their occurrence, sources, and bioaccumulation. Among the studied chemicals, HBCDs predominated in bivalves and sediment, with concentrations of ND-67.52ng/g lipid weight and 3.47-168ng/g dry weight, respectively, while TBBPA was the highest contributor in seawater (ND-2.79ng/L). Compared with a non-aquaculture area, HBCD and PBDE concentrations were significantly higher in all matrices in the aquaculture area (Mann-Whitney U test, p<0.05), suggesting that sources may be located near or associated with the aquaculture areas, such as industrial complexes and expanded polystyrene buoys. Finally, the bioconcentration factor (BCF) and biota-sediment accumulation factor (BSAF) were estimated. Among the studied BFRs, BDE-47 (BCF: 1.70×10 6 L/kg; BSAF: 20.92) and α-HBCD (BCF: 1.05×10 6 L/kg; BSAF: 0.13) showed the highest accumulation potentials in bivalves. Copyright © 2017 Elsevier B.V. All rights reserved.

A study of poultry processing plant noise characteristics and potential noise control techniques

NASA Technical Reports Server (NTRS)

Wyvill, J. C.; Jape, A. D.; Moriarity, L. J.; Atkins, R. D.

1980-01-01

The noise environment in a typical poultry processing plant was characterized by developing noise contours for two representative plants: Central Soya of Athens, Inc., Athens, Georgia, and Tip Top Poultry, Inc., Marietta, Georgia. Contour information was restricted to the evisceration are of both plants because nearly 60 percent of all process employees are stationed in this area during a normal work shift. Both plant evisceration areas were composed of tile walls, sheet metal ceilings, and concrete floors. Processing was performed in an assembly-line fashion in which the birds travel through the area on overhead shackles while personnel remain at fixed stations. Processing machinery was present throughout the area. In general, the poultry processing noise problem is the result of loud sources and reflective surfaces. Within the evisceration area, it can be concluded that only a few major sources (lung guns, a chiller component, and hock cutters) are responsible for essentially all direct and reverberant sound pressure levels currently observed during normal operations. Consequently, any effort to reduce the noise problem must first address the sound power output of these sources and/or the absorptive qualitities of the room.

Cortical sources of ERP in prosaccade and antisaccade eye movements using realistic source models

PubMed Central

Richards, John E.

2013-01-01

The cortical sources of event-related-potentials (ERP) using realistic source models were examined in a prosaccade and antisaccade procedure. College-age participants were presented with a preparatory interval and a target that indicated the direction of the eye movement that was to be made. In some blocks a cue was given in the peripheral location where the target was to be presented and in other blocks no cue was given. In Experiment 1 the prosaccade and antisaccade trials were presented randomly within a block; in Experiment 2 procedures were compared in which either prosaccade and antisaccade trials were mixed in the same block, or trials were presented in separate blocks with only one type of eye movement. There was a central negative slow wave occurring prior to the target, a slow positive wave over the parietal scalp prior to the saccade, and a parietal spike potential immediately prior to saccade onset. Cortical source analysis of these ERP components showed a common set of sources in the ventral anterior cingulate and orbital frontal gyrus for the presaccadic positive slow wave and the spike potential. In Experiment 2 the same cued- and non-cued blocks were used, but prosaccade and antisaccade trials were presented in separate blocks. This resulted in a smaller difference in reaction time between prosaccade and antisaccade trials. Unlike the first experiment, the central negative slow wave was larger on antisaccade than on prosaccade trials, and this effect on the ERP component had its cortical source primarily in the parietal and mid-central cortical areas contralateral to the direction of the eye movement. These results suggest that blocked prosaccade and antisaccade trials results in preparatory or set effects that decreases reaction time, eliminates some cueing effects, and is based on contralateral parietal-central brain areas. PMID:23847476

Widespread presence of naturally occurring perchlorate in high plains of Texas and New Mexico

USGS Publications Warehouse

Rajagopalan, S.; Anderson, T.A.; Fahlquist, L.; Rainwater, Ken A.; Ridley, M.; Jackson, W.A.

2006-01-01

Perchlorate (ClO4-) occurrence in groundwater has previously been linked to industrial releases and the historic use of Chilean nitrate fertilizers. However, recently a number of occurrences have been identified for which there is no obvious anthropogenic source. Groundwater from an area of 155 000 km2 in 56 counties in northwest Texas and eastern New Mexico is impacted by the presence of ClO4-. Concentrations were generally low (<4 ppb), although some areas are impacted by concentrations up to 200 ppb. ClO4- distribution is not related to well type (public water system, domestic, agricultural, or water-table monitoring) or aquifer (Ogallala, Edward Trinity High Plains, Edwards Trinity Plateau, Seymour, or Cenozoic). Results from vertically nested wells strongly indicate a surface source. The source of ClO4- appears to most likely be atmospheric deposition. Evidence supporting this hypothesis primarily relates to the presence of ClO 4- in tritium-free older water, the lack of relation between land use and concentration distribution, the inability of potential anthropogenic sources to account for the estimated mass of ClO4-, and the positive relationship between conserved anions (e.g., IO3-, Cl-, SO4-2) and ClO4-. The ClO4- distribution appears to be mainly related to evaporative concentration and unsaturated transport. This process has led to higher ClO4- and other ion concentrations in groundwater where the water table is relatively shallow, and in areas with lower saturated thickness. Irrigation may have accelerated this process in some areas by increasing the transport of accumulated salts and by increasing the number of evaporative cycles. Results from this study highlight the potential for ClO4- to impact groundwater in arid and semiarid areas through long-term atmospheric deposition. ?? 2006 American Chemical Society.

Strategies for satellite-based monitoring of CO2 from distributed area and point sources

NASA Astrophysics Data System (ADS)

Schwandner, Florian M.; Miller, Charles E.; Duren, Riley M.; Natraj, Vijay; Eldering, Annmarie; Gunson, Michael R.; Crisp, David

2014-05-01

Atmospheric CO2 budgets are controlled by the strengths, as well as the spatial and temporal variabilities of CO2 sources and sinks. Natural CO2 sources and sinks are dominated by the vast areas of the oceans and the terrestrial biosphere. In contrast, anthropogenic and geogenic CO2 sources are dominated by distributed area and point sources, which may constitute as much as 70% of anthropogenic (e.g., Duren & Miller, 2012), and over 80% of geogenic emissions (Burton et al., 2013). Comprehensive assessments of CO2 budgets necessitate robust and highly accurate satellite remote sensing strategies that address the competing and often conflicting requirements for sampling over disparate space and time scales. Spatial variability: The spatial distribution of anthropogenic sources is dominated by patterns of production, storage, transport and use. In contrast, geogenic variability is almost entirely controlled by endogenic geological processes, except where surface gas permeability is modulated by soil moisture. Satellite remote sensing solutions will thus have to vary greatly in spatial coverage and resolution to address distributed area sources and point sources alike. Temporal variability: While biogenic sources are dominated by diurnal and seasonal patterns, anthropogenic sources fluctuate over a greater variety of time scales from diurnal, weekly and seasonal cycles, driven by both economic and climatic factors. Geogenic sources typically vary in time scales of days to months (geogenic sources sensu stricto are not fossil fuels but volcanoes, hydrothermal and metamorphic sources). Current ground-based monitoring networks for anthropogenic and geogenic sources record data on minute- to weekly temporal scales. Satellite remote sensing solutions would have to capture temporal variability through revisit frequency or point-and-stare strategies. Space-based remote sensing offers the potential of global coverage by a single sensor. However, no single combination of orbit and sensor provides the full range of temporal sampling needed to characterize distributed area and point source emissions. For instance, point source emission patterns will vary with source strength, wind speed and direction. Because wind speed, direction and other environmental factors change rapidly, short term variabilities should be sampled. For detailed target selection and pointing verification, important lessons have already been learned and strategies devised during JAXA's GOSAT mission (Schwandner et al, 2013). The fact that competing spatial and temporal requirements drive satellite remote sensing sampling strategies dictates a systematic, multi-factor consideration of potential solutions. Factors to consider include vista, revisit frequency, integration times, spatial resolution, and spatial coverage. No single satellite-based remote sensing solution can address this problem for all scales. It is therefore of paramount importance for the international community to develop and maintain a constellation of atmospheric CO2 monitoring satellites that complement each other in their temporal and spatial observation capabilities: Polar sun-synchronous orbits (fixed local solar time, no diurnal information) with agile pointing allow global sampling of known distributed area and point sources like megacities, power plants and volcanoes with daily to weekly temporal revisits and moderate to high spatial resolution. Extensive targeting of distributed area and point sources comes at the expense of reduced mapping or spatial coverage, and the important contextual information that comes with large-scale contiguous spatial sampling. Polar sun-synchronous orbits with push-broom swath-mapping but limited pointing agility may allow mapping of individual source plumes and their spatial variability, but will depend on fortuitous environmental conditions during the observing period. These solutions typically have longer times between revisits, limiting their ability to resolve temporal variations. Geostationary and non-sun-synchronous low-Earth-orbits (precessing local solar time, diurnal information possible) with agile pointing have the potential to provide, comprehensive mapping of distributed area sources such as megacities with longer stare times and multiple revisits per day, at the expense of global access and spatial coverage. An ad hoc CO2 remote sensing constellation is emerging. NASA's OCO-2 satellite (launch July 2014) joins JAXA's GOSAT satellite in orbit. These will be followed by GOSAT-2 and NASA's OCO-3 on the International Space Station as early as 2017. Additional polar orbiting satellites (e.g., CarbonSat, under consideration at ESA) and geostationary platforms may also become available. However, the individual assets have been designed with independent science goals and requirements, and limited consideration of coordinated observing strategies. Every effort must be made to maximize the science return from this constellation. We discuss the opportunities to exploit the complementary spatial and temporal coverage provided by these assets as well as the crucial gaps in the capabilities of this constellation. References Burton, M.R., Sawyer, G.M., and Granieri, D. (2013). Deep carbon emissions from volcanoes. Rev. Mineral. Geochem. 75: 323-354. Duren, R.M., Miller, C.E. (2012). Measuring the carbon emissions of megacities. Nature Climate Change 2, 560-562. Schwandner, F.M., Oda, T., Duren, R., Carn, S.A., Maksyutov, S., Crisp, D., Miller, C.E. (2013). Scientific Opportunities from Target-Mode Capabilities of GOSAT-2. NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA, White Paper, 6p., March 2013.

Gauging Through the Crowd: A Crowd-Sourcing Approach to Urban Rainfall Measurement and Storm Water Modeling Implications

NASA Astrophysics Data System (ADS)

Yang, Pan; Ng, Tze Ling

2017-11-01

Accurate rainfall measurement at high spatial and temporal resolutions is critical for the modeling and management of urban storm water. In this study, we conduct computer simulation experiments to test the potential of a crowd-sourcing approach, where smartphones, surveillance cameras, and other devices act as precipitation sensors, as an alternative to the traditional approach of using rain gauges to monitor urban rainfall. The crowd-sourcing approach is promising as it has the potential to provide high-density measurements, albeit with relatively large individual errors. We explore the potential of this approach for urban rainfall monitoring and the subsequent implications for storm water modeling through a series of simulation experiments involving synthetically generated crowd-sourced rainfall data and a storm water model. The results show that even under conservative assumptions, crowd-sourced rainfall data lead to more accurate modeling of storm water flows as compared to rain gauge data. We observe the relative superiority of the crowd-sourcing approach to vary depending on crowd participation rate, measurement accuracy, drainage area, choice of performance statistic, and crowd-sourced observation type. A possible reason for our findings is the differences between the error structures of crowd-sourced and rain gauge rainfall fields resulting from the differences between the errors and densities of the raw measurement data underlying the two field types.

Remote sensing and airborne geophysics in the assessment of natural aggregate resources

USGS Publications Warehouse

Knepper, D.H.; Langer, W.H.; Miller, S.H.

1994-01-01

Natural aggregate made from crushed stone and deposits of sand and gravel is a vital element of the construction industry in the United States. Although natural aggregate is a high volume/low value commodity that is relatively abundant, new sources of aggregate are becoming increasingly difficult to find and develop because of rigid industry specifications, political considerations, development and transporation costs, and environmental concerns, especially in urban growth centers where much of the aggregate is used. As the demand for natural aggregate increases in response to urban growth and the repair and expansion of the national infrastructure, new sources of natural aggregate will be required. The USGS has recognized the necessity of developing the capability to assess the potential for natural aggregate sources on Federal lands; at present, no methodology exists for systematically describing and evaluating potential sources of natural aggregate. Because remote sensing and airborne geophysics can detect surface and nearsurface phenomena, these tools may useful for detecting and mapping potential sources of natural aggregate; however, before a methodology for applying these tools can be developed, it is necessary to understand the type, distribution, physical properties, and characteristics of natural aggregate deposits, as well as the problems that will be encountered in assessing their potential value. There are two primary sources of natural aggregate: (1) exposed or near-surface igneous, metamorphic, and sedimentary bedrock that can be crushed, and (2) deposits of sand and gravel that may be used directly or crushed and sized to meet specifications. In any particular area, the availability of bedrock suitable for crushing is a function of the geologic history of the area - the processes that formed, deformed, eroded and exposed the bedrock. Deposits of sand and gravel are primarily surficial deposits formed by the erosion, transportation by water and ice, and deposition of bedrock fragments. Consequently, most sand and gravel deposits are Tertiary or Quaternary in age and are most common in glaciated areas, alluvial basins, and along rivers and streams. The distribution of potential sources of natural aggregate in the United States is closely tied to physiography and the type of bedrock that occurs in an area. Using these criteria, the United States can be divided into 12 regions: western mountain ranges, alluvial basins, Columbia Plateau, Colorado Plateau and Wyoming basin, High Plains, nonglaciated central region, glaciated central region, Piedmont Blue Ridge region, glaciated northeastern and Superior uplands, Atlantic and Gulf coastal plain, Hawaiian Islands, and Alaska. Each region has similar types of natural aggregate sources within its boundary, although there may be wide variations in specific physical and chemical characteristics of the aggregates within a region. Conventional exploration for natural aggregate deposits has been largely a ground-based operation (field mapping, sampling, trenching and augering, resistivity), although aerial photos and topographic maps have been extensively used to target possible deposits for sampling and testing. Today, the exploration process also considers other factors such as the availability of the land, space and water supply for processing purposes, political and environmental factors, and distance from the market; exploration and planning cannot be separated. There are many physical properties and characteristics by which aggregate material is judged to be acceptable or unacceptable for specific applications; most of these properties and characteristics pertain only to individual aggregate particles and not to the bulk deposit. For example, properties of crushed stone aggregate particles such as thermal volume change, solubility, oxidation and hydration reactivity, and particle strength, among many others, are important consi

ENERGY MANAGEMENT INNOVATION IN THE US SKI INDUSTRY

EPA Science Inventory

Ski areas represent a unique opportunity to develop innovative energy management practices in an industrial setting. Through a unique synergy of onsite generation, preferably by renewable sources and innovative technologies, and the energy storage potential of exis...

Towards Understanding Methane Emissions from Abandoned Wells

EPA Science Inventory

Reconciliation of large-scale top-down methane measurements and bottom-up inventories requires complete accounting of source types. Methane emissions from abandoned oil and gas wells is an area of uncertainty. This presentation reviews progress to characterize the potential inv...

Hydrocarbon Source Rocks in the Deep River and Dan River Triassic Basins, North Carolina

USGS Publications Warehouse

Reid, Jeffrey C.; Milici, Robert C.

2008-01-01

This report presents an interpretation of the hydrocarbon source rock potential of the Triassic sedimentary rocks of the Deep River and Dan River basins, North Carolina, based on previously unpublished organic geochemistry data. The organic geochemical data, 87 samples from 28 drill holes, are from the Sanford sub-basin (Cumnock Formation) of the Deep River basin, and from the Dan River basin (Cow Branch Formation). The available organic geochemical data are biased, however, because many of the samples collected for analyses by industry were from drill holes that contained intrusive diabase dikes, sills, and sheets of early Mesozoic age. These intrusive rocks heated and metamorphosed the surrounding sediments and organic matter in the black shale and coal bed source rocks and, thus, masked the source rock potential that they would have had in an unaltered state. In places, heat from the intrusives generated over-mature vitrinite reflectance (%Ro) profiles and metamorphosed the coals to semi-anthracite, anthracite, and coke. The maximum burial depth of these coal beds is unknown, and depth of burial may also have contributed to elevated thermal maturation profiles. The organic geochemistry data show that potential source rocks exist in the Sanford sub-basin and Dan River basin and that the sediments are gas prone rather than oil prone, although both types of hydrocarbons were generated. Total organic carbon (TOC) data for 56 of the samples are greater than the conservative 1.4% TOC threshold necessary for hydrocarbon expulsion. Both the Cow Branch Formation (Dan River basin) and the Cumnock Formation (Deep River basin, Sanford sub-basin) contain potential source rocks for oil, but they are more likely to have yielded natural gas. The organic material in these formations was derived primarily from terrestrial Type III woody (coaly) material and secondarily from lacustrine Type I (algal) material. Both the thermal alteration index (TAI) and vitrinite reflectance data (%Ro) indicate levels of thermal maturity suitable for generation of hydrocarbons. The genetic potential of the source rocks in these Triassic basins is moderate to high and many source rock sections have at least some potential for hydrocarbon generation. Some data for the Cumnock Formation indicate a considerably higher source rock potential than the basin average, with S1 + S2 data in the mid-20 mg HC/g sample range, and some hydrocarbons have been generated. This implies that the genetic potential for all of these strata may have been higher prior to the igneous activity. However, the intergranular porosity and permeability of the Triassic strata are low, which makes fractured reservoirs more attractive as drilling targets. In some places, gravity and magnetic surveys that are used to locate buried intrusive rock may identify local thermal sources that have facilitated gas generation. Alternatively, awareness of the distribution of large intrusive igneous bodies at depth may direct exploration into other areas, where thermal maturation is less than the limits of hydrocarbon destruction. Areas prospective for natural gas also contain large surficial clay resources and any gas discovered could be used as fuel for local industries that produce clay products (principally brick), as well as fuel for other local industries.

Contamination source review for Building E7995, Edgewood Area, Aberdeen Proving Ground, Maryland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Booher, M.N.; Miller, G.A.; Draugelis, A.K.

1995-09-01

The US Army Aberdeen Proving Ground (APG) commissioned Argonne National Laboratory (ANL) to conduct a contamination source review to identify and define areas of toxic or hazardous contaminants and to assess the physical condition and accessibility of APG buildings. The information obtained from the review may be used to assist the US Army in planning for the future use or disposition, of the buildings. The source contamination review consisted of the following tasks: historical records search, physical inspection, photographic documentation, geophysical investigation, investigation of potential hazardous materials facilities (HMFs), and review of available records regarding underground storage tanks. This reportmore » provides the results of the contamination source review for Building E7995. any of the APG facilities constructed between 1917 and the 1960s are no longer used because of obsolescence and their poor state of repair. Because many of these buildings were used for research, development, testing, and/or pilot-scale production of chemical warfare agents and other military substances, the potential exists for portions of the buildings to be contaminated with these substances, their degradation products, and other laboratory or industrial chemicals. These buildings, and associated structures or appurtenances, may contribute to environmental concerns at APG.« less

Bisphenol analogues in surface water and sediment from the shallow Chinese freshwater lakes: Occurrence, distribution, source apportionment, and ecological and human health risk.

PubMed

Yan, Zhengyu; Liu, Yanhua; Yan, Kun; Wu, Shengmin; Han, Zhihua; Guo, Ruixin; Chen, Meihong; Yang, Qiulian; Zhang, Shenghu; Chen, Jianqiu

2017-10-01

Compared to Bisphenol A (BPA), current knowledge on the spatial distribution, potential sources and environmental risk assessment of other bisphenol analogues (BPs) remains limited. The occurrence, distribution and sources of seven BPs were investigated in the surface water and sediment from Taihu Lake and Luoma Lake, which are the Chinese shallow freshwater lakes. Because there are many industries and living areas around Taihu Lake, the total concentrations of ∑BPs were much higher than that in Luoma Lake, which is away from the industry-intensive areas. For the two lakes, BPA was still the dominant BPs in both surface water and sediment, followed by BPF and BPS. The spatial distribution and principal component analysis showed that BPs in Luoma Lake was relatively homogeneous and the potential sources were relatively simple than that in Taihu Lake. The spatial distribution of BPs in sediment of Taihu Lake indicated that ∑BPs positively correlated with the TOC content. For both Taihu Lake and Luoma Lake, the risk assessment at the sampling sites showed that no high risk in surface water and sediment (RQ t  < 1.0, and EEQ t  < 1.0 ng E 2 /L). Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization of soil heavy metal contamination and potential health risk in metropolitan region of northern China.

PubMed

Qiao, Min; Cai, Chao; Huang, Yizong; Liu, Yunxia; Lin, Aijun; Zheng, Yuanming

2011-01-01

Soil in metropolitan region suffers great contamination risk due to the rapid urbanization especially in developing countries. Beijing and Tianjin, together with their surrounding regions, form a mega-metropolitan region in northern China. To assess the soil environmental quality, a total of 458 surface soil samples were collected from this area. Concentrations of Cr, Cu, Pb, Zn, As, Cd, and Hg were analyzed and compared to the Chinese environmental quality standards for soil. Multivariate analysis was carried out to identify the possible sources and Geographic Information Systems techniques were applied to visualize the spatial data. It was found that the primary inputs of As were due to pedogenic sources, whereas Hg was mainly of anthropogenic source. Other elements including Cr, Cu, Pb, Zn, and Cd were from both lithogenic and anthropogenic origins. Health risk assessment based on the maximum heavy metal concentration indicated that As derived from sewage irrigation area can result in carcinogenic lifetime risk due to ingestion and/or dermal contact of soil. The potential non-carcinogenic risk for children is significant for Pb and the cumulative effect of multiple metals is of concern for children in the vicinity of mining site. The results increased our knowledge for understanding natural and anthropogenic sources as well as health risk for metals in metropolitan soil.

Risk assessment of water pollution sources based on an integrated k-means clustering and set pair analysis method in the region of Shiyan, China.

PubMed

Li, Chunhui; Sun, Lian; Jia, Junxiang; Cai, Yanpeng; Wang, Xuan

2016-07-01

Source water areas are facing many potential water pollution risks. Risk assessment is an effective method to evaluate such risks. In this paper an integrated model based on k-means clustering analysis and set pair analysis was established aiming at evaluating the risks associated with water pollution in source water areas, in which the weights of indicators were determined through the entropy weight method. Then the proposed model was applied to assess water pollution risks in the region of Shiyan in which China's key source water area Danjiangkou Reservoir for the water source of the middle route of South-to-North Water Diversion Project is located. The results showed that eleven sources with relative high risk value were identified. At the regional scale, Shiyan City and Danjiangkou City would have a high risk value in term of the industrial discharge. Comparatively, Danjiangkou City and Yunxian County would have a high risk value in terms of agricultural pollution. Overall, the risk values of north regions close to the main stream and reservoir of the region of Shiyan were higher than that in the south. The results of risk level indicated that five sources were in lower risk level (i.e., level II), two in moderate risk level (i.e., level III), one in higher risk level (i.e., level IV) and three in highest risk level (i.e., level V). Also risks of industrial discharge are higher than that of the agricultural sector. It is thus essential to manage the pillar industry of the region of Shiyan and certain agricultural companies in the vicinity of the reservoir to reduce water pollution risks of source water areas. Copyright © 2016 Elsevier B.V. All rights reserved.

Polybrominated diphenyl ethers in residential and agricultural soils from an electronic waste polluted region in South China: distribution, compositional profile, and sources.

PubMed

Zhang, Shaohui; Xu, Xijin; Wu, Yousheng; Ge, Jingjing; Li, Weiqiu; Huo, Xia

2014-05-01

A detailed investigation was conducted to understand the concentration, distribution, profile and possible source of polybrominated diphenyl ethers (PBDEs) in residential and agricultural soils from Guiyu, Shantou, China, one of the largest electronic waste (e-waste) recycling and dismantling areas in the world. Ten PBDEs were analyzed in 46 surface soil samples in terms of individual and total concentrations, together with soil organic matter concentrations. Much higher concentrations of the total PBDEs were predicted in the residential areas (more than 2000 ng g(-1)), exhibiting a clear urban source, while in the agricultural areas, concentrations were lower than 1500 ng g(-1). PBDE-209 was the most dominant congener among the study sites, indicating the prevalence of commercial deca-PBDE. However signature congeners from commercial octa-PBDE were also found. The total PBDE concentrations were significantly correlated with each individual PBDE. Principal component analysis indicated that PBDEs were mainly distributed in three groups according to the number of bromine atoms on the phenyl rings, and potential source. This study showed that the informal e-waste recycling has already introduced PBDEs into surrounding areas as pollutant which thus warrants an urgent investigation into the transport of PBDEs in the soil-plant system of agricultural areas. Copyright © 2013 Elsevier Ltd. All rights reserved.

Urban transmission of schistosomiasis: new epidemiological situation in the forest area of Pernambuco.

PubMed

Gomes, Elainne Christine de Souza; Mesquita, Millena Carla da Silva; Rehn, Vitorina Nerivânia Covello; Nascimento, Wheverton Ricardo Correia do; Loyo, Rodrigo; Barbosa, Constança Simões

2016-01-01

Schistosomiasis is considered an endemic disease in Vitória de Santo Antão, Pernambuco, a district which has presented both high incidence and prevalence of it for decades. Poor environmental conditions lead to contamination of water sources in rural areas, which are used by the population during daily activities, resulting in typical transmission. Recently, there has been evidence of vector snails in urban areas, which could set a new model for schistosomiasis transmission in this district. To identify the new epidemiological situation for the urban transmission of schistosomiasis in Vitória de Santo Antão, Pernambuco. A malacological survey was conducted in all water sources in the city limits to investigate schistosomiasis vector snails (Biomphalaria spp.). The collected snails were examined for taxonomic identification and Schistosoma mansoni infection. All breeding sites were georeferenced to build risk maps through the TrackMaker PRO program and ArcGIS software. We identified 22 Biomphalaria straminea breeding sites and collected 1,704 snails. One of these breeding sites was identified as a source of transmission and seven as potential sources of transmission. The designed maps identified two risk areas of urban transmission of schistosomiasis and expansion areas for breeding sites, establishing an increased risk of transmission to the population. This study verified the existence of a new epidemiological situation in which the possibility of the urban transmission of the disease was confirmed.

Appraisal of data for ground-water quality in Nebraska

USGS Publications Warehouse

Engberg, R.A.

1984-01-01

This report summarizes existing data for groundwater quality in Nebraska and indicates their adequacy as a data base. Analyses have been made of water from nearly 10,000 wells by 8 agencies. Those analyses that meet reliability criteria have been aggregated by geologic source of water into four principal aquifer groupings--Holocene-Pleistocene aquifers, Tertiary aquifers, Mesozoic aquifers, and Paleozoic aquifers. For each aquifer grouping, data for specific conductance and 24 constituents in the water are summarized statistically. Also, diagrams are presented showing differences in statistical parameters, or in chemical composition, of water from the different aquifer groupings. Additionally, for each grouping except Paleozoic aquifers, maps show ranges in concentration of dissolved solids, calcium, alkalinity, and sulfate. In areas where data are insufficient to delimit, ranges in concentration also are shown on the maps. Point-source contamination has been identified at 41 locations and nonpoint-source contamination in 3 areas, namely, the central Platte Valley, Holt County, and Boyd County. Potential for nonpoint-source contamination exists in 10 major areas, which together comprise more than one-third of the State. Existing data are mostly from specific projects having limited areas and objectives. Consequently, a lack of data exists for other areas and for certain geologic units, particularly the Mesozoic and Paleozoic aquifers. Specific data needs for each of the four principal aquifer groupings are indicated in a matrix table.

Conventional and reciprocal approaches to the inverse dipole localization problem for N(20)-P (20) somatosensory evoked potentials.

PubMed

Finke, Stefan; Gulrajani, Ramesh M; Gotman, Jean; Savard, Pierre

2013-01-01

The non-invasive localization of the primary sensory hand area can be achieved by solving the inverse problem of electroencephalography (EEG) for N(20)-P(20) somatosensory evoked potentials (SEPs). This study compares two different mathematical approaches for the computation of transfer matrices used to solve the EEG inverse problem. Forward transfer matrices relating dipole sources to scalp potentials are determined via conventional and reciprocal approaches using individual, realistically shaped head models. The reciprocal approach entails calculating the electric field at the dipole position when scalp electrodes are reciprocally energized with unit current-scalp potentials are obtained from the scalar product of this electric field and the dipole moment. Median nerve stimulation is performed on three healthy subjects and single-dipole inverse solutions for the N(20)-P(20) SEPs are then obtained by simplex minimization and validated against the primary sensory hand area identified on magnetic resonance images. Solutions are presented for different time points, filtering strategies, boundary-element method discretizations, and skull conductivity values. Both approaches produce similarly small position errors for the N(20)-P(20) SEP. Position error for single-dipole inverse solutions is inherently robust to inaccuracies in forward transfer matrices but dependent on the overlapping activity of other neural sources. Significantly smaller time and storage requirements are the principal advantages of the reciprocal approach. Reduced computational requirements and similar dipole position accuracy support the use of reciprocal approaches over conventional approaches for N(20)-P(20) SEP source localization.

Relationship between land-use and sources and fate of nitrate in groundwater in a typical recharge area of the North China Plain.

PubMed

Wang, Shiqin; Zheng, Wenbo; Currell, Matthew; Yang, Yonghui; Zhao, Huan; Lv, Mengyu

2017-12-31

Identification of different nitrate sources in groundwater is challenging in areas with diverse land use and multiple potential inputs. An area with mixed land-uses, typical of the piedmont-plain recharge area of the North China Plain, was selected to investigate different nitrate sources and the impact of land use on nitrate distribution in groundwater. Multiple environmental tracers were examined, including major ions, stable isotopes of water (δ 2 H-H 2 O, δ 18 O-H 2 O) and nitrate (δ 15 N-NO 3 - and δ 18 O-NO 3 - ). Groundwater was sampled from four land-use types; natural vegetation (NV), farmland (FL), economic forestland (EF) and residential areas (RA). A mixing model using δ 18 O and Cl - concentrations showed that groundwater recharge predominantly comprises precipitation and lateral groundwater flow from areas of natural vegetation in the upper catchment, while irrigation return water and wastewater from septic tanks were major inputs in farmland and residential areas, respectively. Land use variation is the major contributing factor to different nitrate concentrations. In total, 80%, 49% and 86% of samples from RA, FL and EF, respectively exceeded the WHO standard (50mg/L NO 3 - ), compared to 6.9% of samples from NV. Isotopes of δ 15 N-NO 3 - and δ 18 O-NO 3 - verified that nitrate in groundwater of the NV (with δ 15 N ranging from 1.7‰ to 4.7‰) was sourced from soil and precipitation. Examination of δ 15 N-NO 3 - vs δ 18 O-NO 3 - values along with multivariate statistical analysis (principle component and cluster analysis) helped identify sources with overlapping isotopic values in other land-use areas (where δ 15 N values range from 2.5‰ to 10.2‰). Manure and septic waste were dominant sources for most groundwater with high NO 3 - and Cl - concentrations in both farmland and residential areas. The lack of de-nitrification and fact that the area is a recharge zone for the North China Plain highlight the importance of controlling nitrate sources through careful application of manure and fertilizers, and control of septic leakage. Copyright © 2017 Elsevier B.V. All rights reserved.

Heavy Metal Contamination Assessment and Partition for Industrial and Mining Gathering Areas

PubMed Central

Guan, Yang; Shao, Chaofeng; Ju, Meiting

2014-01-01

Industrial and mining activities have been recognized as the major sources of soil heavy metal contamination. This study introduced an improved Nemerow index method based on the Nemerow and geo-accumulation index. Taking a typical industrial and mining gathering area in Tianjin (China) as example, this study then analyzed the contamination sources as well as the ecological and integrated risks. The spatial distribution of the contamination level and ecological risk were determined using Geographic Information Systems. The results are as follows: (1) Zinc showed the highest contaminant level in the study area; the contamination levels of the other seven heavy metals assessed were relatively lower. (2) The combustion of fossil fuels and emissions from industrial and mining activities were the main sources of contamination in the study area. (3) The overall contamination level of heavy metals in the study area ranged from heavily contaminated to extremely contaminated and showed an uneven distribution. (4) The potential ecological risk showed an uneven distribution, and the overall ecological risk level ranged from low to moderate. This study also emphasized the importance of partition in industrial and mining areas, the extensive application of spatial analysis methods, and the consideration of human health risks in future studies. PMID:25032743

Water-supply potential of major streams and the Upper Floridan Aquifer in the vicinity of Savannah, Georgia

USGS Publications Warehouse

Garza, Reggina; Krause, Richard E.

1997-01-01

Surface- and ground-water resources in the Savannah, Georgia, area were evaluated for potential water-supply development. Stream-discharge and water-quality data were analyzed for two major streams considered to be viable water-supply sources. A ground-water flow model was developed to be used in conjunction with other previously calibrated models to simulate the effects of additional pumpage on water levels near areas of saltwater intrusion at Brunswick and seawater encroachment at Hilton Head Island. Hypothetical scenarios also were simulated involving redistributions and small increases, and decreases in pumpage.

Evaluation of Healthcare Interventions and Big Data: Review of Associated Data Issues.

PubMed

Asche, Carl V; Seal, Brian; Kahler, Kristijan H; Oehrlein, Elisabeth M; Baumgartner, Meredith Greer

2017-08-01

Although the analysis of 'big data' holds tremendous potential to improve patient care, there remain significant challenges before it can be realized. Accuracy and completeness of data, linkage of disparate data sources, and access to data are areas that require particular focus. This article discusses these areas and shares strategies to promote progress. Improvement in clinical coding, innovative matching methodologies, and investment in data standardization are potential solutions to data validation and linkage problems. Challenges to data access still require significant attention with data ownership, security needs, and costs representing significant barriers to access.

Concentration, ozone formation potential and source analysis of volatile organic compounds (VOCs) in a thermal power station centralized area: A study in Shuozhou, China.

PubMed

Yan, Yulong; Peng, Lin; Li, Rumei; Li, Yinghui; Li, Lijuan; Bai, Huiling

2017-04-01

Volatile organic compounds (VOCs) from two sampling sites (HB and XB) in a power station centralized area, in Shuozhou city, China, were sampled by stainless steel canisters and measured by gas chromatography-mass selective detection/flame ionization detection (GC-MSD/FID) in the spring and autumn of 2014. The concentration of VOCs was higher in the autumn (HB, 96.87 μg/m 3 ; XB, 58.94 μg/m 3 ) than in the spring (HB, 41.49 μg/m 3 ; XB, 43.46 μg/m 3 ), as lower wind speed in the autumn could lead to pollutant accumulation, especially at HB, which is a new urban area surrounded by residential areas and a transportation hub. Alkanes were the dominant group at both HB and XB in both sampling periods, but the contribution of aromatic pollutants at HB in the autumn was much higher than that of the other alkanes (11.16-19.55%). Compared to other cities, BTEX pollution in Shuozhou was among the lowest levels in the world. Because of the high levels of aromatic pollutants, the ozone formation potential increased significantly at HB in the autumn. Using the ratio analyses to identify the age of the air masses and analyze the sources, the results showed that the atmospheric VOCs at XB were strongly influenced by the remote sources of coal combustion, while at HB in the spring and autumn were affected by the remote sources of coal combustion and local sources of vehicle emission, respectively. Source analysis conducted using the Positive Matrix Factorization (PMF) model at Shuozhou showed that coal combustion and vehicle emissions made the two largest contributions (29.98% and 21.25%, respectively) to atmospheric VOCs. With further economic restructuring, the influence of vehicle emissions on the air quality should become more significant, indicating that controlling vehicle emissions is key to reducing the air pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multicriteria analysis for sources of renewable energy using data from remote sensing

NASA Astrophysics Data System (ADS)

Matejicek, L.

2015-04-01

Renewable energy sources are major components of the strategy to reduce harmful emissions and to replace depleting fossil energy resources. Data from remote sensing can provide information for multicriteria analysis for sources of renewable energy. Advanced land cover quantification makes it possible to search for suitable sites. Multicriteria analysis, together with other data, is used to determine the energy potential and socially acceptability of suggested locations. The described case study is focused on an area of surface coal mines in the northwestern region of the Czech Republic, where the impacts of surface mining and reclamation constitute a dominant force in land cover changes. High resolution satellite images represent the main input datasets for identification of suitable sites. Solar mapping, wind predictions, the location of weirs in watersheds, road maps and demographic information complement the data from remote sensing for multicriteria analysis, which is implemented in a geographic information system (GIS). The input spatial datasets for multicriteria analysis in GIS are reclassified to a common scale and processed with raster algebra tools to identify suitable sites for sources of renewable energy. The selection of suitable sites is limited by the CORINE land cover database to mining and agricultural areas. The case study is focused on long term land cover changes in the 1985-2015 period. Multicriteria analysis based on CORINE data shows moderate changes in mapping of suitable sites for utilization of selected sources of renewable energy in 1990, 2000, 2006 and 2012. The results represent map layers showing the energy potential on a scale of a few preference classes (1-7), where the first class is linked to minimum preference and the last class to maximum preference. The attached histograms show the moderate variability of preference classes due to land cover changes caused by mining activities. The results also show a slight increase in the more preferred classes for utilization of sources of renewable energy due to an increase area of reclaimed sites. Using data from remote sensing, such as the multispectral images and the CORINE land cover datasets, can reduce the financial resources currently required for finding and assessing suitable areas.

Contamination source review for Building E6891, Edgewood Area, Aberdeen Proving Ground, Maryland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zellmer, S.D.; Draugelis, A.K.; Rueda, J.

1995-09-01

The US Army Aberdeen Proving Ground (APG) commissioned Argonne National Laboratory (ANL) to conduct a contamination source review to identify and define areas of toxic or hazardous contaminants and to assess the physical condition and accessibility of various APG buildings. This report provides the results of the contamination source review for Building E6891. The information obtained from this review may be used to assist the US Army in planning for the future use or disposition of the buildings. The contamination source review consisted of the following tasks: historical records search, physical inspection, photographic documentation, geophysical investigation, and collection of airmore » samples. This building is part of the Lauderick Creek Concrete Slab Test Site, located in the Lauderick Creek Area in the Edgewood Area. Many of the APG facilities constructed between 1917 and the 1960s are no longer used because of obsolescence and their poor state of repair. Because many of these buildings were used for research, development, testing, and/or pilot-scale production of chemical warfare agents and other military substances the potential exists` for portions of the buildings to be contaminated with these substances, their degradation products, and other laboratory or industrial chemicals. These buildings and associated structures or appurtenances may contribute to environmental concerns at APG.« less

Internal dosimetry monitoring equipment: Present and future

DOE Office of Scientific and Technical Information (OSTI.GOV)

Selby, J.; Carbaugh, E.H.; Lynch, T.P.

1993-09-01

We have attempted to characterize the current and future status of in vivo and in vitro measurement programs coupled with the associated radioanalytical methods and workplace monitoring. Developments in these areas must be carefully integrated by internal dosimetrists, radiochemists and field health physicists. Their goal should be uniform improvement rather than to focus on one specific area (e.g., dose modeling) to the neglect of other areas where the measurement capabilities are substantially less sophisticated and, therefore, the potential source of error is greatest.

PUBLIC EXPOSURE TO MULTIPLE RF SOURCES IN GHANA.

PubMed

Deatanyah, P; Abavare, E K K; Menyeh, A; Amoako, J K

2018-03-16

This paper describes an effort to respond to the suggestion in World Health Organization (WHO) research agenda to better quantify potential exposure levels from a range of radiofrequency (RF) sources at 200 public access locations in Ghana. Wide-band measurements were performed-with a spectrum analyser and a log-periodic antenna using three-point spatial averaging method. The overall results represented a maximum of 0.19% of the ICNIRP reference levels for public exposure. These results were generally lower than found in some previous but were 58% (2.0 dB) greater, than found in similar work conducted in the USA. Major contributing sources of RF fields were identified to be FM broadcast and mobile base station sites. Three locations with the greatest measured RF fields could represent potential areas for epidemiological studies.

Antifouling paint particles: Sources, occurrence, composition and dynamics.

PubMed

Soroldoni, Sanye; Castro, Ítalo Braga; Abreu, Fiamma; Duarte, Fabio Andrei; Choueri, Rodrigo Brasil; Möller, Osmar Olinto; Fillmann, Gilberto; Pinho, Grasiela Lopes Leães

2018-06-15

Sources, occurrence, composition and dynamics of antifouling paint particles (APPs) were assessed in Patos Lagoon estuary (PLE), Southern Brazil. Ten areas including boatyards, a marina and artisanal fishing harbors were identified in the estuarine system as potential sources of APPs. The APPs generated in these areas were highly heterogeneous considering the size, shape and composition. Based on an estimate of antifouling paint usage and amount of boats in each studied area, artisanal fishing harbors could be the main source of particles to PLE. However, relatively high amounts of APPs, which ranged from 130 to 40,300 μg g -1 , were detected in sediments collected in front of boatyards and a marina. The uneven distribution of APPs levels among the sediment samples were probably due to the presence of diffuse sources (fishing harbors) associated to "hotspots" (boatyards and marina) along the study area. Additionally, data of settling experiment indicate that size, shape and density of APPs, combined to local hydrodynamics, appears to contribute to the mobility of these residues within the estuary. In the main channel of PLE, smaller particles tend to be transported to adjacent coastal zone while particles tend to be deposited in the sediment surface of sheltered areas. Since different trace metals, and booster biocides were detected in APPs that were not correctly disposed, these particles can be considered as an important source of contamination to aquatic environments. The present data suggest that APPs represent an environmental problem for aquatic systems in Brazil, since the country lacks legislation in addition to inefficient control mechanisms. An improvement in boat maintenance processes are urgently needed to avoid this continuous release of APPs into the aquatic systems. Copyright © 2018 Elsevier Ltd. All rights reserved.

Coronal Field Opens at Lower Height During the Solar Cycles 22 and 23 Minimum Periods: IMF Comparison Suggests the Source Surface Should Be Lowered (Postprint)

DTIC Science & Technology

2012-03-01

understood simply from differences in the areas of the coronal holes , as opposed to differences in the surface fields within them. In this study, we...invoke smaller source surface radii in the potential-field source-surface (PFSS) model to construct a consistent picture of the observed coronal holes ...that the values of ≈1.9 R and ≈1.8 R for the cycles 22 and 23 minimum periods, respectively, produce the best results. The larger coronal holes

High resolution tsunami modelling for the evaluation of potential risk areas in Setúbal (Portugal)

NASA Astrophysics Data System (ADS)

Ribeiro, J.; Silva, A.; Leitão, P.

2011-08-01

The use of high resolution hydrodynamic modelling to simulate the potential effects of tsunami events can provide relevant information about the most probable inundation areas. Moreover, the consideration of complementary data such as the type of buildings, location of priority equipment, type of roads, enables mapping of the most vulnerable zones, computing of the expected damage on man-made structures, constrain of the definition of rescue areas and escape routes, adaptation of emergency plans and proper evaluation of the vulnerability associated with different areas and/or equipment. Such an approach was used to evaluate the specific risks associated with a potential occurrence of a tsunami event in the region of Setúbal (Portugal), which was one of the areas most seriously affected by the 1755 tsunami. In order to perform an evaluation of the hazard associated with the occurrence of a similar event, high resolution wave propagation simulations were performed considering different potential earthquake sources with different magnitudes. Based on these simulations, detailed inundation maps associated with the different events were produced. These results were combined with the available information on the vulnerability of the local infrastructures (building types, roads and streets characteristics, priority buildings) in order to impose restrictions in the production of high-scale potential damage maps, escape routes and emergency routes maps.

The potential use of rainwater as alternative source of drinking water by using laterite soil as natural adsorbent

NASA Astrophysics Data System (ADS)

Omar, Khairunnisa Fakhriah Mohd; Palaniandy, Puganeshwary; Adlan, Mohd Nordin; Aziz, Hamidi Abdul; Subramaniam, Ambarasi

2017-10-01

Generally, the rainwater has low concentration of pollutants, whereby it is applicable for domestic water supply. Due to the low concentration of pollutants, further treatment such as adsorption is necessary to treat the harvested rainwater as an alternative source of drinking water supply. Therefore, this research has been carried out to determine the quality of rainwater from different types of locations, which are; rural residential area, urban residential area, agricultural area, industrial area, and open surface. The rainwater sampling was carried out from September 2014 to December 2015. The parameters that have been analysed during the sampling process are chemical oxygen demand (COD), turbidity, heavy metals, and Escherichia coli (E.coli). The sampling results show that the rainwater provides low concentration of contaminants. Thus, it has high potential to be used as alternative source of potable and non potable water supply with a suitable treatment. Due to that, an experimental work contained of 86 of designated experiments for a batch study has been carried out to determine the performance of laterite soil as an adsorbent to remove pollutants that present in the rainwater (i.e. zinc, manganese, and E.coli). The operating factors involved in the experimental works are pH, mass of adsorbents, contact time, initial concentration of zinc, manganese, and E.coli. In this study, the experimental data of the batch study was analysed by developing regression model equation and analysis of variance. Perturbation plots were analysed to determine the effectiveness of the operating factors by developing response surface model, resulting that the high removals of zinc, manganese, and E.coli are 95.8%, 94.05% and 100%, respectively. Overall, this research works found out that the rainwater has a good quality as alternative source of drinking water by providing a suitable treatment. The application of laterite soil as natural adsorbent shows that it has potential to be used as the response surface model provide a good removal for zinc, manganese, and E.coli.

Evaluation of Unbound Engineered Nanoparticles from a Worker Exposure and Environmental Release Perspective

NASA Astrophysics Data System (ADS)

Bunker, K.; Casuccio, G.; Lersch, T.; Ogle, R.; Wahl, L.

2009-12-01

Nanotechnology and the use of unbound engineered nanoparticles (UNP) is a rapidly developing area of materials science. UNP are defined as engineered nanoparticles that are not contained within a matrix that would prevent the nanoparticles from being mobile and a potential source of exposure. At this time there are no regulatory environmental release limits or worker exposure limits for UNP. The Lawrence Berkeley National Laboratory (LBNL) has initiated a study to evaluate worker exposure and potential environmental release of UNP related to various research activities at LBNL. The study is being performed to help identify and manage potential health and safety hazards as well as environmental impacts related to UNP. A key component of the study is the characterization of starting (source) UNP materials to assist in the determination of worker exposure and environmental release. Analysis of the starting materials is being used to establish source signatures. The source signatures will then be used in the evaluation of worker exposure and environmental release. This presentation will provide an overview of the LBNL study with a focus on the methodologies being used to analyze the samples.

Characteristics of fine particulate matter and its sources in an industrialized coastal city, Ningbo, Yangtze River Delta, China

NASA Astrophysics Data System (ADS)

Wang, Weifeng; Yu, Jie; Cui, Yang; He, Jun; Xue, Peng; Cao, Wan; Ying, Hongmei; Gao, Wenkang; Yan, Yingchao; Hu, Bo; Xin, Jinyuan; Wang, Lili; Liu, Zirui; Sun, Yang; Ji, Dongsheng; Wang, Yuesi

2018-05-01

Chemical information is essential in understanding the characteristics of airborne particles, and effectively controlling airborne particulate matter pollution, but it remains unclear in some regions due to the scarcity of measurement data. In the present study, 92 daily PM2.5 (particulate matter with an aerodynamic diameter ≤ 2.5 μm) samples as well as historical observation data of air pollutants were collected in urban Ningbo, one of important industrial cities in the coastal area of the Yangtze River Delta, China in autumn and winter (from Nov. 2014 to Feb. 2015). Various chemical species in PM2.5 were determined including water soluble ions, organic and elemental carbon and elements. Positive matrix factorization model, cluster analysis of back trajectories, potential source contribution function (PSCF) model and concentration-weighted trajectory (CWT) model were used for identifying sources, apportioning contributions from each source and tracking potential areas of sources. The results showed the PM2.5 concentration has been reducing; nonetheless, the concentrations of PM2.5 are still much higher than the World Health Organization guideline with high PM2.5 concentrations observed in autumn and winter for the past few years. During the sampling period, the average PM2.5 mass concentration was 77 μg/m3 with the major components of OC, NO3-, SO42 -, NH4+ and EC, accounting for 24.7, 18.8, 14.5, 11.8 and 6.4% in the total mass concentration, respectively. When the aerosol pollution got worse during the sampling period, the NO3-, SO42 - and NH4+ concentrations increased accordingly and NO3- appeared to increase at fastest rate. SO42 - transported from industrial areas led to slight difference in spatial distribution of SO42 - in Ningbo. More secondary organic carbon was formed and the enrichment factor values of Cu, Ag, Cd, Sn and Pb increased with the degradation of air quality. Ten types of sources were identified for PM2.5 in the autumn and winter of Ningbo, which are metallurgical industry, biomass burning and waste incineration, manufacturing related with Mo, chlor-alkli chemical industry, oil combustion, vehicular emission, secondary source, soil dust, road dust and manufacturing related with Cr, accounting for 9.4, 4.8, 9.4, 7.6, 8.1, 18.7, 27.6, 2, 7.1 and 5.2% of the total sources, respectively. There were five groups of air parcels arriving in Ningbo, of which inland air masses originating from Shandong province were associated with the highest PM2.5 concentrations. Despite the slight differences, it was obvious that the north of Jiangxi, east of Anhui, west of Jiangsu, south of Shandong were identified as major potential sources-areas of SO42 -, NO3-, NH4+, Cl-, OC and EC by both PSCF and CWT models.

Mapping of wind energy potential over the Gobi Desert in Northwest China based on multiple sources of data

NASA Astrophysics Data System (ADS)

Li, Li; Wang, Xinyuan; Luo, Lei; Zhao, Yanchuang; Zong, Xin; Bachagha, Nabil

2018-06-01

In recent years, wind energy has been a fastgrowing alternative source of electrical power due to its sustainability. In this paper, the wind energy potential over the Gobi Desert in Northwest China is assessed at the patch scale using geographic information systems (GIS). Data on land cover, topography, and administrative boundaries and 11 years (2000‒2010) of wind speed measurements were collected and used to map and estimate the region's wind energy potential. Based on the results, it was found that continuous regions of geographical potential (GeoP) are located in the middle of the research area (RA), with scattered areas of similar GeoP found in other regions. The results also show that the technical potential (TecP) levels are about 1.72‒2.67 times (2.20 times on average) higher than the actual levels. It was found that the GeoP patches can be divided into four classes: unsuitable regions, suitable regions, more suitable regions, and the most suitable regions. The GeoP estimation shows that 0.41 billion kW of wind energy are potentially available in the RA. The suitable regions account for 25.49%, the more suitable regions 24.45%, and the most suitable regions for more than half of the RA. It is also shown that Xinjiang and Gansu are more suitable for wind power development than Ningxia.

A coupled model approach to reduce nonpoint-source pollution resulting from predicted urban growth: A case study in the Ambos Nogales watershed

USGS Publications Warehouse

Norman, L.M.; Guertin, D.P.; Feller, M.

2008-01-01

The development of new approaches for understanding processes of urban development and their environmental effects, as well as strategies for sustainable management, is essential in expanding metropolitan areas. This study illustrates the potential of linking urban growth and watershed models to identify problem areas and support long-term watershed planning. Sediment is a primary source of nonpoint-source pollution in surface waters. In urban areas, sediment is intermingled with other surface debris in transport. In an effort to forecast the effects of development on surface-water quality, changes predicted in urban areas by the SLEUTH urban growth model were applied in the context of erosion-sedimentation models (Universal Soil Loss Equation and Spatially Explicit Delivery Models). The models are used to simulate the effect of excluding hot-spot areas of erosion and sedimentation from future urban growth and to predict the impacts of alternative erosion-control scenarios. Ambos Nogales, meaning 'both Nogaleses,' is a name commonly used for the twin border cities of Nogales, Arizona and Nogales, Sonora, Mexico. The Ambos Nogales watershed has experienced a decrease in water quality as a result of urban development in the twin-city area. Population growth rates in Ambos Nogales are high and the resources set in place to accommodate the rapid population influx will soon become overburdened. Because of its remote location and binational governance, monitoring and planning across the border is compromised. One scenario described in this research portrays an improvement in water quality through the identification of high-risk areas using models that simulate their protection from development and replanting with native grasses, while permitting the predicted and inevitable growth elsewhere. This is meant to add to the body of knowledge about forecasting the impact potential of urbanization on sediment delivery to streams for sustainable development, which can be accomplished in a virtual environment. Copyright ?? 2008 by Bellwether Publishing, Ltd. All rights reserved.

Late Cretaceous-Cenozoic Basin framework and petroleum potential of Panama and Costa Rica

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mann, P.; Kolarsky, R.

Despite its location between major petroleum provinces in northwestern South America and northern Central America, there is a widespread negative perception of the petroleum potential of Panama and Costa Rica in southern Central America. Several factors may contribute to this perception: (1) the on and offshore geology of many areas has only be studied in a reconnaissance fashion; (2) sandstone reservoirs and source rocks are likely to be of poor quality because Upper Cretaceous-Cenozoic sandstones are eroded from island arc or oceanic basement rocks and because oil-prone source rocks are likely to be scarce in near-arc basins; and (3) structuralmore » traps are likely to be small and fragmented because of complex late Cenozoic thrust and strike-slip tectonics. On the other hand, onshore oil and gas seeps, shows and small production in wildcat wells, and source rocks with TOC values up to 26% suggest the possibility of future discoveries. In this talk, we present the results of a regional study using 3100 km of offshore seismic lines kindly provided by industry. Age and stratigraphic control of offshore lines is constrained by limited well data and detailed field studies of basin outcrops in coastal areas. We describe the major structures, stratigraphy, and tectonic history of the following areas: Gulf of Panama and Gulf of Chiriqui of Panama and the Pacific and Caribbean margins of Costa Rica.« less

Model assessment of atmospheric pollution control schemes for critical emission regions

NASA Astrophysics Data System (ADS)

Zhai, Shixian; An, Xingqin; Liu, Zhao; Sun, Zhaobin; Hou, Qing

2016-01-01

In recent years, the atmospheric environment in portions of China has become significantly degraded and the need for emission controls has become urgent. Because more international events are being planned, it is important to implement air quality assurance targeted at significant events held over specific periods of time. This study sets Yanqihu (YQH), Beijing, the location of the 2014 Beijing APEC (Asia-Pacific Economic Cooperation) summit, as the target region. By using the atmospheric inversion model FLEXPART, we determined the sensitive source zones that had the greatest impact on the air quality of the YQH region in November 2012. We then used the air-quality model Models-3/CMAQ and a high-resolution emissions inventory of the Beijing-Tianjian-Hebei region to establish emission reduction tests for the entire source area and for specific sensitive source zones. This was achieved by initiating emission reduction schemes at different ratios and different times. The results showed that initiating a moderate reduction of emissions days prior to a potential event is more beneficial to the air quality of Beijing than initiating a high-strength reduction campaign on the day of the event. The sensitive source zone of Beijing (BJ-Sens) accounts for 54.2% of the total source area of Beijing (BJ), but its reduction effect reaches 89%-100% of the total area, with a reduction efficiency 1.6-1.9 times greater than that of the entire area. The sensitive source zone of Huabei (HuaB-Sens.) only represents 17.6% of the total area of Huabei (HuaB), but its emission reduction effect reaches 59%-97% of the entire area, with a reduction efficiency 4.2-5.5 times greater than that of the total area. The earlier that emission reduction measures are implemented, the greater the effect they have on preventing the transmission of pollutants. In addition, expanding the controlling areas to sensitive provinces and cities around Beijing (HuaB-sens) can significantly accelerate the reduction effects compared to controlling measures only in the Beijing sensitive source zone (BJ-Sens). Therefore, when enacting emission reduction schemes, cooperating with surrounding provinces and cities, as well as narrowing the reduction scope to specific sensitive source zones prior to unfavorable meteorological conditions, can help reduce emissions control costs and improve the efficiency and maneuverability of emission reduction schemes.

15 CFR 917.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... life, fish, shellfish, marine mammals, and wildlife. Nonliving resources include energy sources..., tangible, intangible, actual, or potential) which is located in, derived from, or traceable to, the marine..., the nutrient rich areas, and the other components of the marine environment which contribute to or...

10 CFR 835.401 - General requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Monitoring of Individuals and Areas § 835.401 General... engineered and administrative controls in containing radioactive material and reducing radiation exposure; and (6) Identify and control potential sources of individual exposure to radiation and/or radioactive...

10 CFR 835.401 - General requirements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Monitoring of Individuals and Areas § 835.401 General... engineered and administrative controls in containing radioactive material and reducing radiation exposure; and (6) Identify and control potential sources of individual exposure to radiation and/or radioactive...

10 CFR 835.401 - General requirements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Monitoring of Individuals and Areas § 835.401 General... engineered and administrative controls in containing radioactive material and reducing radiation exposure; and (6) Identify and control potential sources of individual exposure to radiation and/or radioactive...

10 CFR 835.401 - General requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Monitoring of Individuals and Areas § 835.401 General... engineered and administrative controls in containing radioactive material and reducing radiation exposure; and (6) Identify and control potential sources of individual exposure to radiation and/or radioactive...

10 CFR 835.401 - General requirements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Monitoring of Individuals and Areas § 835.401 General... engineered and administrative controls in containing radioactive material and reducing radiation exposure; and (6) Identify and control potential sources of individual exposure to radiation and/or radioactive...

Modeled Sources, Transport, and Accumulation of Dissolved Solids in Water Resources of the Southwestern United States

USGS Publications Warehouse

Anning, D.W.

2011-01-01

Information on important source areas for dissolved solids in streams of the southwestern United States, the relative share of deliveries of dissolved solids to streams from natural and human sources, and the potential for salt accumulation in soil or groundwater was developed using a SPAtially Referenced Regressions On Watershed attributes model. Predicted area-normalized reach-catchment delivery rates of dissolved solids to streams ranged from <10(kg/year)/km2 for catchments with little or no natural or human-related solute sources in them to 563,000(kg/year)/km2 for catchments that were almost entirely cultivated land. For the region as a whole, geologic units contributed 44% of the dissolved-solids deliveries to streams and the remaining 56% of the deliveries came from the release of solutes through irrigation of cultivated and pasture lands, which comprise only 2.5% of the land area. Dissolved-solids accumulation is manifested as precipitated salts in the soil or underlying sediments, and (or) dissolved salts in soil-pore or sediment-pore water, or groundwater, and therefore represents a potential for aquifer contamination. Accumulation rates were <10,000(kg/year)/km2 for many hydrologic accounting units (large river basins), but were more than 40,000(kg/year)/km2 for the Middle Gila, Lower Gila-Agua Fria, Lower Gila, Lower Bear, Great Salt Lake accounting units, and 247,000(kg/year)/km2 for the Salton Sea accounting unit. ?? 2011 American Water Resources Association. This article is a U.S. Government work and is in the public domain in the USA.

Genetic profiling to determine potential origins of boll weevils (Coleoptera: Curculionidae) captured in a Texas eradication zone: endemicity, immigration, or sabotage?

PubMed

Kim, Kyung Seok; Sappington, Thomas W; Allen, Charles T

2008-12-01

Thirty-seven boll weevils, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), were captured in pheromone traps near Lubbock, TX, in the Southern High Plains/Caprock eradication zone during August-October 2006. No boll weevils had been captured in this zone or neighboring zones to the north earlier in the year, and only very low numbers had been captured in neighboring zones to the south and east. Therefore, the captures near Lubbock were unexpected. Five of the weevils captured the last week of August were preserved and genotyped at 10 microsatellite loci for comparison with a database of genotypes for 22 boll weevil populations sampled from eight U.S. states and four locations in Mexico. The Lubbock population itself is an unlikely source, suggesting that the captured weevils probably did not originate from a low-level endemic population. Populations from eastern states, Mexico, and Big Spring, TX, can be confidently excluded as potential source regions. Although the Weslaco and Kingsville, TX, areas cannot be statistically excluded, they are unlikely sources. The most likely sources are nearby areas in New Mexico, TX, or southwest Oklahoma, or from areas of eastern Texas represented by Waxahachie and El Campo populations. Together, genetic and circumstantial evidence suggest either that the trapped boll weevils are the offspring of alone mated female that immigrated from eastern Texas earlier in the summer or that weevils originally captured near Waxahachie but now long-dead were planted in the traps by a disgruntled employee of the eradication program.

Vista-LA: Mapping methane-emitting infrastructure in the Los Angeles megacity

NASA Astrophysics Data System (ADS)

Carranza, Valerie; Rafiq, Talha; Frausto-Vicencio, Isis; Hopkins, Francesca M.; Verhulst, Kristal R.; Rao, Preeti; Duren, Riley M.; Miller, Charles E.

2018-03-01

Methane (CH4) is a potent greenhouse gas (GHG) and a critical target of climate mitigation efforts. However, actionable emission reduction efforts are complicated by large uncertainties in the methane budget on relevant scales. Here, we present Vista, a Geographic Information System (GIS)-based approach to map potential methane emissions sources in the South Coast Air Basin (SoCAB) that encompasses Los Angeles, an area with a dense, complex mixture of methane sources. The goal of this work is to provide a database that, together with atmospheric observations, improves methane emissions estimates in urban areas with complex infrastructure. We aggregated methane source location information into three sectors (energy, agriculture, and waste) following the frameworks used by the State of California GHG Inventory and the Intergovernmental Panel on Climate Change (IPCC) Guidelines for GHG Reporting. Geospatial modeling was applied to publicly available datasets to precisely geolocate facilities and infrastructure comprising major anthropogenic methane source sectors. The final database, Vista-Los Angeles (Vista-LA), is presented as maps of infrastructure known or expected to emit CH4. Vista-LA contains over 33 000 features concentrated on < 1 % of land area in the region. Currently, Vista-LA is used as a planning and analysis tool for atmospheric measurement surveys of methane sources, particularly for airborne remote sensing, and methane hotspot detection using regional observations. This study represents a first step towards developing an accurate, spatially resolved methane flux estimate for point sources in SoCAB, with the potential to address discrepancies between bottom-up and top-down methane emissions accounting in this region. The Vista-LA datasets and associated metadata are available from the Oak Ridge National Laboratory Distributed Active Archive Center for Biogeochemical Dynamics (ORNL DAAC; https://doi.org/10.3334/ORNLDAAC/1525).

Sensitivity of WRF-chem predictions to dust source function specification in West Asia

NASA Astrophysics Data System (ADS)

Nabavi, Seyed Omid; Haimberger, Leopold; Samimi, Cyrus

2017-02-01

Dust storms tend to form in sparsely populated areas covered by only few observations. Dust source maps, known as source functions, are used in dust models to allocate a certain potential of dust release to each place. Recent research showed that the well known Ginoux source function (GSF), currently used in Weather Research and Forecasting Model coupled with Chemistry (WRF-chem), exhibits large errors over some regions in West Asia, particularly near the IRAQ/Syrian border. This study aims to improve the specification of this critical part of dust forecasts. A new source function based on multi-year analysis of satellite observations, called West Asia source function (WASF), is therefore proposed to raise the quality of WRF-chem predictions in the region. WASF has been implemented in three dust schemes of WRF-chem. Remotely sensed and ground-based observations have been used to verify the horizontal and vertical extent and location of simulated dust clouds. Results indicate that WRF-chem performance is significantly improved in many areas after the implementation of WASF. The modified runs (long term simulations over the summers 2008-2012, using nudging) have yielded an average increase of Spearman correlation between observed and forecast aerosol optical thickness by 12-16 percent points compared to control runs with standard source functions. They even outperform MACC and DREAM dust simulations over many dust source regions. However, the quality of the forecasts decreased with distance from sources, probably due to deficiencies in the transport and deposition characteristics of the forecast model in these areas.

Using enteric pathogens to assess sources of fecal contamination in the Silurian Dolomite Aquifer: Preliminary results

USGS Publications Warehouse

Muldoon, Maureen A; Borchardt, Mark A.; Spencer, Susan K.; Hunt, Randall J.; Owens, David

2018-01-01

The fractured Silurian dolomite aquifer is an important, but vulnerable, source of drinking water in northeast Wisconsin (Sherrill in Geology and ground water in Door County, Wisconsin, with emphasis on contamination potential in the Silurian dolomite, 1978; Bradbury and Muldoon in Hydrogeology and groundwater monitoring of fractured dolomite in the Upper Door Priority Watershed, Door County, Wisconsin, 1992; Muldoon and Bradbury in Assessing seasonal variations in recharge and water quality in the Silurian aquifer in areas with thicker soil cover. p 45, 2010). Areas underlain by the Silurian dolomite aquifer are extremely vulnerable to groundwater contamination from various land-use activities, especially the disposal of human wastewater and dairy manure. Currently there is no consensus as to which source of wastewater generates the greater impact to the aquifer.

Groundwater vulnerability and risk mapping using GIS, modeling and a fuzzy logic tool.

PubMed

Nobre, R C M; Rotunno Filho, O C; Mansur, W J; Nobre, M M M; Cosenza, C A N

2007-12-07

A groundwater vulnerability and risk mapping assessment, based on a source-pathway-receptor approach, is presented for an urban coastal aquifer in northeastern Brazil. A modified version of the DRASTIC methodology was used to map the intrinsic and specific groundwater vulnerability of a 292 km(2) study area. A fuzzy hierarchy methodology was adopted to evaluate the potential contaminant source index, including diffuse and point sources. Numerical modeling was performed for delineation of well capture zones, using MODFLOW and MODPATH. The integration of these elements provided the mechanism to assess groundwater pollution risks and identify areas that must be prioritized in terms of groundwater monitoring and restriction on use. A groundwater quality index based on nitrate and chloride concentrations was calculated, which had a positive correlation with the specific vulnerability index.

Neural correlates of encoding processes predicting subsequent cued recall and source memory.

PubMed

Angel, Lucie; Isingrini, Michel; Bouazzaoui, Badiâa; Fay, Séverine

2013-03-06

In this experiment, event-related potentials were used to examine whether the neural correlates of encoding processes predicting subsequent successful recall differed from those predicting successful source memory retrieval. During encoding, participants studied lists of words and were instructed to memorize each word and the list in which it occurred. At test, they had to complete stems (the first four letters) with a studied word and then make a judgment of the initial temporal context (i.e. list). Event-related potentials recorded during encoding were segregated according to subsequent memory performance to examine subsequent memory effects (SMEs) reflecting successful cued recall (cued recall SME) and successful source retrieval (source memory SME). Data showed a cued recall SME on parietal electrode sites from 400 to 1200 ms and a late inversed cued recall SME on frontal sites in the 1200-1400 ms period. Moreover, a source memory SME was reported from 400 to 1400 ms on frontal areas. These findings indicate that patterns of encoding-related activity predicting successful recall and source memory are clearly dissociated.

Hydrocarbon potential evaluation of the source rocks from the Abu Gabra Formation in the Sufyan Sag, Muglad Basin, Sudan

NASA Astrophysics Data System (ADS)

Qiao, Jinqi; Liu, Luofu; An, Fuli; Xiao, Fei; Wang, Ying; Wu, Kangjun; Zhao, Yuanyuan

2016-06-01

The Sufyan Sag is one of the low-exploration areas in the Muglad Basin (Sudan), and hydrocarbon potential evaluation of source rocks is the basis for its further exploration. The Abu Gabra Formation consisting of three members (AG3, AG2 and AG1 from bottom to top) was thought to be the main source rock formation, but detailed studies on its petroleum geology and geochemical characteristics are still insufficient. Through systematic analysis on distribution, organic matter abundance, organic matter type, organic matter maturity and characteristics of hydrocarbon generation and expulsion of the source rocks from the Abu Gabra Formation, the main source rock members were determined and the petroleum resource extent was estimated in the study area. The results show that dark mudstones are the thickest in the AG2 member while the thinnest in the AG1 member, and the thickness of the AG3 dark mudstone is not small either. The AG3 member have developed good-excellent source rock mainly with Type I kerogen. In the Southern Sub-sag, the AG3 source rock began to generate hydrocarbons in the middle period of Bentiu. In the early period of Darfur, it reached the hydrocarbon generation and expulsion peak. It is in late mature stage currently. The AG2 member developed good-excellent source rock mainly with Types II1 and I kerogen, and has lower organic matter abundance than the AG3 member. In the Southern Sub-sag, the AG2 source rock began to generate hydrocarbons in the late period of Bentiu. In the late period of Darfur, it reached the peak of hydrocarbon generation and its expulsion. It is in middle mature stage currently. The AG1 member developed fair-good source rock mainly with Types II and III kerogen. Throughout the geological evolution history, the AG1 source rock has no effective hydrocarbon generation or expulsion processes. Combined with basin modeling results, we have concluded that the AG3 and AG2 members are the main source rock layers and the Southern Sub-sag is the main source kitchen in the study area. The AG3 and AG2 source rocks have supplied 58.1% and 41.9% of the total hydrocarbon generation, respectively, and 54.9% and 45.1% of the total hydrocarbon expulsion, respectively. Their hydrocarbon expulsion efficiency ratios are 71.0% and 62.3%, respectively. The Southern Sub-sag has supplied more than 90% of the total amounts of hydrocarbon generation and its expulsion.

Characterization of VOC sources in an urban area based on PTR-MS measurements and receptor modelling.

PubMed

Stojić, A; Stojić, S Stanišić; Šoštarić, A; Ilić, L; Mijić, Z; Rajšić, S

2015-09-01

In this study, the concentrations of volatile organic compounds were measured by the use of proton transfer reaction mass spectrometry, together with NO x , NO, NO2, SO2, CO and PM10 and meteorological parameters in an urban area of Belgrade during winter 2014. The multivariate receptor model US EPA Unmix was applied to the obtained dataset resolving six source profiles, which can be attributed to traffic-related emissions, gasoline evaporation/oil refineries, petrochemical industry/biogenic emissions, aged plumes, solid-fuel burning and local laboratories. Besides the vehicle exhaust, accounting for 27.6 % of the total mixing ratios, industrial emissions, which are present in three out of six resolved profiles, exert a significant impact on air quality in the urban area. The major contribution of regional and long-range transport was determined for source profiles associated with petrochemical industry/biogenic emissions (40 %) and gasoline evaporation/oil refineries (29 %) using trajectory sector analysis. The concentration-weighted trajectory model was applied with the aim of resolving the spatial distribution of potential distant sources, and the results indicated that emission sources from neighbouring countries, as well as from Slovakia, Greece, Poland and Scandinavian countries, significantly contribute to the observed concentrations.

Sources of organic compounds in fine soil and sand particles during winter in the metropolitan area of Riyadh, Saudi Arabia.

PubMed

Rushdi, Ahmed I; Al-Mutlaq, Khalid; Simoneit, Bernd R T

2005-11-01

Major advances have been made in molecular marker analysis to distinguish between natural and anthropogenic organic matter inputs to the atmosphere. Resuspension of soil and sand by wind is one of the major mechanisms that produces particle dusts in the atmosphere. Soil and sand samples from the Riyadh area were collected in winter 2002, sieved to remove coarse particles and extracted with a mixture of dichloromethane and methanol (3:1, v:v). The total extracts were analyzed by gas chromatography-mass spectrometry in order to characterize the contents and identify the potential sources of the organic components. The major organic compounds of these extracts were derived from natural biogenic and anthropogenic sources. Organic compounds from natural sources, mainly vegetation, were major in samples from outside the city of Riyadh and included n-alkanes, n-alkanoic acids, n- alkanols, methyl alkanoates, and sterols. Anthropogenic inputs were significant in the fine particles of soil and sand samples collected from populated areas of the city. They consisted mainly of n-alkanes, hopanes, UCM (from vehicular emissions), and plasticizers (from discarded plastics, e.g., shopping bags). Carbohydrates had high concentrations in all samples and indicate sources from decomposed cellulose fibers and/or the presence of viable microbiota such as bacteria and fungi.

Risks to global biodiversity from fossil-fuel production exceed those from biofuel production

DOE PAGES

Dale, Virginia H.; Parish, Esther S.; Kline, Keith L.

2014-12-02

Potential global biodiversity impacts from near-term gasoline production are compared to biofuel, a renewable liquid transportation fuel expected to substitute for gasoline in the near term (i.e., from now until c. 2030). Petroleum exploration activities are projected to extend across more than 5.8 billion ha of land and ocean worldwide (of which 3.1 billion is on land), much of which is in remote, fragile terrestrial ecosystems or off-shore oil fields that would remain relatively undisturbed if not for interest in fossil fuel production. Future biomass production for biofuels is projected to fall within 2.0 billion ha of land, most ofmore » which is located in areas already impacted by human activities. A comparison of likely fuel-source areas to the geospatial distribution of species reveals that both energy sources overlap with areas with high species richness and large numbers of threatened species. At the global scale, future petroleum production areas intersect more than double the area and higher total number of threatened species than future biofuel production. Energy options should be developed to optimize provisioning of ecosystem services while minimizing negative effects, which requires information about potential impacts on critical resources. Furthermore, energy conservation and identifying and effectively protecting habitats with high-conservation value are critical first steps toward protecting biodiversity under any fuel production scenario.« less

Risks to global biodiversity from fossil-fuel production exceed those from biofuel production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dale, Virginia H.; Parish, Esther S.; Kline, Keith L.

Potential global biodiversity impacts from near-term gasoline production are compared to biofuel, a renewable liquid transportation fuel expected to substitute for gasoline in the near term (i.e., from now until c. 2030). Petroleum exploration activities are projected to extend across more than 5.8 billion ha of land and ocean worldwide (of which 3.1 billion is on land), much of which is in remote, fragile terrestrial ecosystems or off-shore oil fields that would remain relatively undisturbed if not for interest in fossil fuel production. Future biomass production for biofuels is projected to fall within 2.0 billion ha of land, most ofmore » which is located in areas already impacted by human activities. A comparison of likely fuel-source areas to the geospatial distribution of species reveals that both energy sources overlap with areas with high species richness and large numbers of threatened species. At the global scale, future petroleum production areas intersect more than double the area and higher total number of threatened species than future biofuel production. Energy options should be developed to optimize provisioning of ecosystem services while minimizing negative effects, which requires information about potential impacts on critical resources. Furthermore, energy conservation and identifying and effectively protecting habitats with high-conservation value are critical first steps toward protecting biodiversity under any fuel production scenario.« less

Pollution assessment and source apportionment of heavy metals in contaminated site soils

NASA Astrophysics Data System (ADS)

Zheng, Hongbo; Ma, Yan

2018-03-01

Pollution characteristics of heavy metals in soil were analyzed with a typical contaminated site as the case area. The pollution degree of the element was evaluated by indexes of geoaccumulation (Igeo). The potential ecological risk of heavy metals was assessed with potential ecological risk index model. Principal component analysis (PCA) model was simultaneously carried out to identify the main sources of heavy metals in topsoils. The results indicated that: 1. Mean values of 11 kinds of metals in topsoils were greater than respective soil background values, following the order: Zn>Pb>V>Cr>Cu>Ni>Co>As>Sb>Cd>Hg. Heavy metals with a certain accumulation in the research area were significantly affected by external factors. 2. Igeo results showed that Cd and Zn reached strongly polluted degree, while Pb with moderately to strongly polluted, Sb and Hg with moderately polluted, Cu, Co, Ni and Cr with unpolluted to moderately polluted, V and As with un-polluted. 3. Potential ecological risk assessment showed the degree of ecological risk with Cd at very high risk, Hg at high risk, Pb at moderate risk and others at low risk. The comprehensive risk of all the metals was very high. 4. PCA got three main sources with contributions, including industrial activities (44.18%), traffic and burning dust (26.68%) and soil parent materials (12.20%).

Egg production patterns of two invertebrate species in rocky subtidal areas under different fishing regimes along the coast of central Chile

PubMed Central

Ospina-Álvarez, Andres; González, Catherine; Fernández, Miriam

2017-01-01

Fishing is a major source of human impact, reducing density and size of a wide range of exploited species in comparison to areas exhibiting strong regulations (no-take and partially protected areas, including Territorial Use Rights for Fisheries, TURFs). Since size and density might have important consequences on reproduction, and therefore natural re-seeding, we monitored adult size, density and potential fecundity of the keyhole limpet (Fissurella latimarginata) and the red sea urchin (Loxechinus albus) in areas under two fishing regimes (TURFs and Open Access Areas, OAAs). Analyzing the distribution of suitable habitats, we predict spatial patterns of potential egg production, to identify reproductive hotspots along the central coast of Chile. The current system of TURFs in central Chile showed higher potential egg production of F. latimarginata and of L. albus than expected under a complete OAAs scenario (67 and 52% respectively). Potential egg production showed more than a twofold reduction when the complete TURFs scenario was compared against complete OAAs condition in both species. Individual size and density explained between 60% and 100% of the variability in potential egg production, suggesting the importance of the enhancement of both biological variables in TURFs in Chile. Potential egg production for both species in the northern part of the studied domain was higher due to the combined effect of (a) suitable habitat and (b) concentration of TURFs. Our results suggest that partially protected areas, such as TURFs can significantly enhance the production of propagules that could seed exploited areas. PMID:28481886

Low latitude ice core evidence for dust deposition on high altitude glaciers

NASA Astrophysics Data System (ADS)

Gabrielli, P.; Thompson, L. G.

2017-12-01

Polar ice cores from Antarctica and Greenland have provided a wealth of information on dust emission, transport and deposition over glacial to interglacial timescales. These ice cores mainly entrap dust transported long distances from source areas such as Asia for Greenland and South America for Antarctica. Thus, these dust records provide paleo-information about the environmental conditions at the source and the strength/pathways of atmospheric circulation at continental scales. Ice cores have also been extracted from high altitude glaciers in the mid- and low-latitudes and provide dust records generally extending back several centuries and in a few cases back to the last glacial period. For these glaciers the potential sources of dust emission include areas that are close or adjacent to the drilling site which facilitates the potential for a strong imprinting of local dust in the records. In addition, only a few high altitude glaciers allow the reconstruction of past snow accumulation and hence the expression of the dust records in terms of fluxes. Due to their extreme elevation, a few of these high altitude ice cores offer dust histories with the potential to record environmental conditions at remote sources. Dust records (in terms of dust concentration/size, crustal trace elements and terrigenous cations) from Africa, the European Alps, South America and the Himalayas are examined over the last millennium. The interplay of the seasonal atmospheric circulation (e.g. westerlies, monsoons and vertical convection) is shown to play a major role in determining the intensity and origin of dust fallout to the high altitude glaciers around the world.

DOE Office of Scientific and Technical Information (OSTI.GOV)

LaFreniere, L. M.; Environmental Science Division

In 1997, low levels of carbon tetrachloride (below the maximum contaminant level [MCL] of 5 {micro}g/L) were detected in groundwater at Inman, Kansas, by the Kansas Department of Health and Environment (KDHE). The 1997 KDHE sampling was conducted under the U.S. Department of Agriculture (USDA) private well sampling program. The Commodity Credit Corporation (CCC), a USDA agency, operated a grain storage facility in Inman from 1954 to 1965. Carbon tetrachloride is the contaminant of primary concern at sites associated with former CCC/USDA grain storage operations. Inman is located in southwest McPherson County, approximately 10 mi southwest of the city ofmore » McPherson (Figure 1.1). To determine whether the former CCC/USDA facility at Inman is a potential contaminant source and its possible relationship to the contamination in groundwater, the CCC/USDA has agreed to conduct an investigation at Inman, in accordance with the Intergovernmental Agreement between the KDHE and the Farm Service Agency of the USDA. For this work plan, Argonne compiled historical data related to the previous investigations and grain storage operations at Inman. Through a review of documents acquired from all available sources, other potential contaminant source areas (in addition to the former CCC/USDA facility) have been identified as (1) the commercial grain storage structures northwest of Inman, along the railroad right-of-way, and (2) small former private grain storage facilities west of Main Street and near the former CCC/USDA facility at the southern edge of Inman (Figure 1.2). Previous investigations and the potential source areas are discussed in Section 2.« less

Steady-state visually evoked potential correlates of human body perception.

PubMed

Giabbiconi, Claire-Marie; Jurilj, Verena; Gruber, Thomas; Vocks, Silja

2016-11-01

In cognitive neuroscience, interest in the neuronal basis underlying the processing of human bodies is steadily increasing. Based on functional magnetic resonance imaging studies, it is assumed that the processing of pictures of human bodies is anchored in a network of specialized brain areas comprising the extrastriate and the fusiform body area (EBA, FBA). An alternative to examine the dynamics within these networks is electroencephalography, more specifically so-called steady-state visually evoked potentials (SSVEPs). In SSVEP tasks, a visual stimulus is presented repetitively at a predefined flickering rate and typically elicits a continuous oscillatory brain response at this frequency. This brain response is characterized by an excellent signal-to-noise ratio-a major advantage for source reconstructions. The main goal of present study was to demonstrate the feasibility of this method to study human body perception. To that end, we presented pictures of bodies and contrasted the resulting SSVEPs to two control conditions, i.e., non-objects and pictures of everyday objects (chairs). We found specific SSVEPs amplitude differences between bodies and both control conditions. Source reconstructions localized the SSVEP generators to a network of temporal, occipital and parietal areas. Interestingly, only body perception resulted in activity differences in middle temporal and lateral occipitotemporal areas, most likely reflecting the EBA/FBA.

Occurrence and potential sources of pyrethroid insecticides in stream sediments from seven U.S. metropolitan areas

USGS Publications Warehouse

Kuivila, Kathryn; Hladik, Michelle; Ingersoll, Christopher G.; Kemble, Nile E.; Moran, Patrick W.; Calhoun, Daniel L.; Nowell, Lisa H.; Gilliom, Robert J.

2012-01-01

A nationally consistent approach was used to assess the occurrence and potential sources of pyrethroid insecticides in stream bed sediments from seven metropolitan areas across the United States. One or more pyrethroids were detected in almost half of the samples, with bifenthrin detected the most frequently (41%) and in each metropolitan area. Cyhalothrin, cypermethrin, permethrin, and resmethrin were detected much less frequently. Pyrethroid concentrations and Hyalella azteca mortality in 28-d tests were lower than in most urban stream studies. Log-transformed total pyrethroid toxic units (TUs) were significantly correlated with survival and bifenthrin was likely responsible for the majority of the observed toxicity. Sampling sites spanned a wide range of urbanization and log-transformed total pyrethroid concentrations were significantly correlated with urban land use. Dallas/Fort Worth had the highest pyrethroid detection frequency (89%), the greatest number of pyrethroids (4), and some of the highest concentrations. Salt Lake City had a similar percentage of detections but only bifenthrin was detected and at lower concentrations. The variation in pyrethroid concentrations among metropolitan areas suggests regional differences in pyrethroid use and transport processes. This study shows that pyrethroids commonly occur in urban stream sediments and may be contributing to sediment toxicity across the country.

Tectono-thermal Evolution of the Lower Paleozoic Petroleum Source Rocks in the Southern Lublin Trough: Implications for Shale Gas Exploration from Maturity Modelling

NASA Astrophysics Data System (ADS)

Botor, Dariusz

2018-03-01

The Lower Paleozoic basins of eastern Poland have recently been the focus of intensive exploration for shale gas. In the Lublin Basin potential unconventional play is related to Lower Silurian source rocks. In order to assess petroleum charge history of these shale gas reservoirs, 1-D maturity modeling has been performed. In the Łopiennik IG-1 well, which is the only well that penetrated Lower Paleozoic strata in the study area, the uniform vitrinite reflectance values within the Paleozoic section are interpreted as being mainly the result of higher heat flow in the Late Carboniferous to Early Permian times and 3500 m thick overburden eroded due to the Variscan inversion. Moreover, our model has been supported by zircon helium and apatite fission track dating. The Lower Paleozoic strata in the study area reached maximum temperature in the Late Carboniferous time. Accomplished tectono-thermal model allowed establishing that petroleum generation in the Lower Silurian source rocks developed mainly in the Devonian - Carboniferous period. Whereas, during Mesozoic burial, hydrocarbon generation processes did not develop again. This has negative influence on potential durability of shale gas reservoirs.

Potentially toxic trace element contamination, sources, and pollution assessment in farmlands, Bijie City, southwestern China.

PubMed

Yuan, Zhimin; Yao, Jun; Wang, Fei; Guo, Zunwei; Dong, Zeqin; Chen, Feng; Hu, Yu; Sunahara, Geoffrey

2017-01-01

Artisanal zinc smelting activities, which had been widely applied in Bijie City, Guizhou Province, southwestern of China, can pollute surrounding farmlands. In the present study, 177 farmland topsoil samples of Bijie City were collected and 11 potentially toxic trace elements (PTEs), namely Pb, Zn, Cu, Ni, Co, Mn, Cr, V, Hg, As, and Cd were tested to characterize the concentrations, sources, and ecological risks. Mean concentrations of these PTEs in soils were (mg/kg) as follows: Pb (127), Zn (379), Cu (93.1), Ni (54.6), Co (26.2), Mn (1095), Cr (133), V (206), Hg (0.15), As (16.2), and Cd (3.08). Pb, Zn, and Cd had coefficients of variation greater than 100% and showed a high uneven distribution and spatial variability in the study area. Correlation coefficient analysis and principal component analysis (PCA) were used to quantify potential pollution sources. Results showed that Cu, Ni, Co, Mn, and V came from natural sources, whereas Pb, Zn, Hg, As, and Cd came from anthropogenic pollution sources. Geoaccumulation index and potential ecological risk indices were employed to study the pollution degree of PTEs, which revealed that Pb and Cd shared the greatest contamination and would pose serious ecological risks to the surrounding environment. The results of this study could help the local government managers to establish pollution control strategies and to secure food safety.

Characterization of the near-source population around five ...

EPA Pesticide Factsheets

Many ports are currently preparing for increased freight traffic, which may result in elevated local air pollution in areas near the port and freight transportation corridors. In this study, a geographical information system (GIS) analysis of areas surrounding five ports – Port of New York and New Jersey, Port of Virginia, Port of Savannah, Port of Miami, and Port of Houston – was conducted to characterize the population that might be affected by air emissions from the freight transportation network and to determine which sources had the potential to affect the most people. Defining “near-source” populations as living within 300 m of the freight transportation network, namely the port and associated truck routes, railroads, and intermodal facilities (e. g. rail yards and warehouses); near-source populations ranged from 37,000 to over a million within 10 km of a port. At the ports considered, the population living within 300 m of the port boundary constituted <10 % of the total near-source population. Sensitive population exposure was also indicated, such as the 81 day care centers and K-12 schools in near-source environments within 2 km of the Port of New York and New Jersey. Minority groups constituted 55 % to 85 % of the near-source populations in the five port areas. For four of the five ports, the mean and median income of the near-source population was lower and the minority percentage was higher than the population living adjacent to the near-sou

Source regions and transport pathways of PM2.5 at a regional background site in East China

NASA Astrophysics Data System (ADS)

Zhang, Yanru; Zhang, Hongliang; Deng, Junjun; Du, Wenjiao; Hong, Youwei; Xu, Lingling; Qiu, Yuqing; Hong, Zhenyu; Wu, Xin; Ma, Qianli; Yao, Jie; Chen, Jinsheng

2017-10-01

PM2.5 samples were collected daily at the Lin'an regional background station (LA) in Zhejiang, China during 2014-2015 and the major chemical components including organic carbon (OC), elemental carbon (EC) and water-soluble inorganic ions (WSII) were determined. Backward trajectory clustering and potential source contribution function (PSCF) were adopted for identifying the transport pathways and potential source regions of PM2.5 at LA. The annual mean concentration was 68.9 ± 28.3 μg m-3, indicating severe pollution in East China. Obvious seasonal variations were found, with highest level in winter and lowest in summer. Carbonaceous aerosols and WSII were the predominant compositions, accounting for 30.7% and 53.5% of PM2.5, respectively. Secondary inorganic ions (SO42-, NO3-, and NH4+) made a total contribution of 45.2% to PM2.5. Heterogeneous formation played a dominant role in SO42- formation and NH4+ formation promoted NO3- formation. Stationary sources played a more important role than mobile sources based on NO3-/SO42- ratio of 0.53. Aerosol environment at LA was ammonium-poor and SO42- was only neutralized sufficiently by NH4+ with the predominant production of (NH4)2SO4 in winter. Four major transport pathways of air masses at LA were found based on trajectory clustering. Air masses from the northwest Gobi areas passing over the heavily polluted regions in North and Central China had the highest levels of PM2.5, followed by the air masses from Central China. PSCF results suggested that surrounding areas in the Yangtze River Delta region were major regional origins of PM2.5 and its major components. Northern region was an important origin for carbonaceous components, and southwestern region was significant for secondary inorganic ions. This study helps understand PM2.5 characteristics, identify potential source regions and effectively control PM2.5 in East China.

Kinematic and Dynamic Source Rupture Scenario for Potential Megathrust Event along the Southernmost Ryukyu Trench

NASA Astrophysics Data System (ADS)

Lin, T. C.; Hu, F.; Chen, X.; Lee, S. J.; Hung, S. H.

2017-12-01

Kinematic source model is widely used for the simulation of an earthquake, because of its simplicity and ease of application. On the other hand, dynamic source model is a more complex but important tool that can help us to understand the physics of earthquake initiation, propagation, and healing. In this study, we focus on the southernmost Ryukyu Trench which is extremely close to northern Taiwan. Interseismic GPS data in northeast Taiwan shows a pattern of strain accumulation, which suggests the maximum magnitude of a potential future earthquake in this area is probably about magnitude 8.7. We develop dynamic rupture models for the hazard estimation of the potential megathrust event based on the kinematic rupture scenarios which are inverted using the interseismic GPS data. Besides, several kinematic source rupture scenarios with different characterized slip patterns are also considered to constrain the dynamic rupture process better. The initial stresses and friction properties are tested using the trial-and-error method, together with the plate coupling and tectonic features. An analysis of the dynamic stress field associated with the slip prescribed in the kinematic models can indicate possible inconsistencies with physics of faulting. Furthermore, the dynamic and kinematic rupture models are considered to simulate the ground shaking from based on 3-D spectral-element method. We analyze ShakeMap and ShakeMovie from the simulation results to evaluate the influence over the island between different source models. A dispersive tsunami-propagation simulation is also carried out to evaluate the maximum tsunami wave height along the coastal areas of Taiwan due to coseismic seafloor deformation of different source models. The results of this numerical simulation study can provide a physically-based information of megathrust earthquake scenario for the emergency response agency to take the appropriate action before the really big one happens.

Isotopic Recorders of Pollution in Heterogeneous Urban Areas

NASA Astrophysics Data System (ADS)

Pataki, D. E.; Cobley, L.; Smith, R. M.; Ehleringer, J. R.; Chritz, K.

2017-12-01

A significant difficulty in quantifying urban pollution lies in the extreme spatial and temporal heterogeneity of cities. Dense sources of both point and non-point source pollution as well as the dynamic role of human activities, which vary over very short time scales and small spatial scales, complicate efforts to establish long-term urban monitoring networks that are relevant at neighborhood, municipal, and regional scales. Fortunately, the natural abundance of isotopes of carbon, nitrogen, and other elements provides a wealth of information about the sources and fate of urban atmospheric pollution. In particular, soils and plant material integrate pollution sources and cycling over space and time, and have the potential to provide long-term records of pollution dynamics that extend back before atmospheric monitoring data are available. Similarly, sampling organic material at high spatial resolution can provide "isoscapes" that shed light on the spatial heterogeneity of pollutants in different urban parcels and neighborhoods, along roads of varying traffic density, and across neighborhoods of varying affluence and sociodemographic composition. We have compiled numerous datasets of the isotopic composition of urban organic matter that illustrate the potential for isotopic monitoring of urban areas as a means of understanding hot spots and hot moments in urban atmospheric biogeochemistry. Findings to date already reveal the critical role of affluence, economic activity, demographic change, and land management practices in influencing urban pollution sources and sinks, and suggest an important role of stable isotope and radioisotope measurements in urban atmospheric and biogeochemical monitoring.

Multiscale analysis of potential fields by a ridge consistency criterion: the reconstruction of the Bishop basement

NASA Astrophysics Data System (ADS)

Fedi, M.; Florio, G.; Cascone, L.

2012-01-01

We use a multiscale approach as a semi-automated interpreting tool of potential fields. The depth to the source and the structural index are estimated in two steps: first the depth to the source, as the intersection of the field ridges (lines built joining the extrema of the field at various altitudes) and secondly, the structural index by the scale function. We introduce a new criterion, called 'ridge consistency' in this strategy. The criterion is based on the principle that the structural index estimations on all the ridges converging towards the same source should be consistent. If these estimates are significantly different, field differentiation is used to lessen the interference effects from nearby sources or regional fields, to obtain a consistent set of estimates. In our multiscale framework, vertical differentiation is naturally joint to the low-pass filtering properties of the upward continuation, so is a stable process. Before applying our criterion, we studied carefully the errors on upward continuation caused by the finite size of the survey area. To this end, we analysed the complex magnetic synthetic case, known as Bishop model, and evaluated the best extrapolation algorithm and the optimal width of the area extension, needed to obtain accurate upward continuation. Afterwards, we applied the method to the depth estimation of the whole Bishop basement bathymetry. The result is a good reconstruction of the complex basement and of the shape properties of the source at the estimated points.

Spatial and Temporal Dust Source Variability in Northern China Identified Using Advanced Remote Sensing Analysis

NASA Technical Reports Server (NTRS)

Taramelli, A.; Pasqui, M.; Barbour, J.; Kirschbaum, D.; Bottai, L.; Busillo, C.; Calastrini, F.; Guarnieri, F.; Small, C.

2013-01-01

The aim of this research is to provide a detailed characterization of spatial patterns and temporal trends in the regional and local dust source areas within the desert of the Alashan Prefecture (Inner Mongolia, China). This problem was approached through multi-scale remote sensing analysis of vegetation changes. The primary requirements for this regional analysis are high spatial and spectral resolution data, accurate spectral calibration and good temporal resolution with a suitable temporal baseline. Landsat analysis and field validation along with the low spatial resolution classifications from MODIS and AVHRR are combined to provide a reliable characterization of the different potential dust-producing sources. The representation of intra-annual and inter-annual Normalized Difference Vegetation Index (NDVI) trend to assess land cover discrimination for mapping potential dust source using MODIS and AVHRR at larger scale is enhanced by Landsat Spectral Mixing Analysis (SMA). The combined methodology is to determine the extent to which Landsat can distinguish important soils types in order to better understand how soil reflectance behaves at seasonal and inter-annual timescales. As a final result mapping soil surface properties using SMA is representative of responses of different land and soil cover previously identified by NDVI trend. The results could be used in dust emission models even if they are not reflecting aggregate formation, soil stability or particle coatings showing to be critical for accurately represent dust source over different regional and local emitting areas.

Source identification and trends in concentrations of gaseous and fine particulate principal species in Seoul, South Korea.

PubMed

Kang, Choong-Min; Kang, Byung-Wook; Lee, Hak Sung

2006-07-01

Ambient measurements were made using two sets of annular denuder system during the four seasons (April 2001 to February 2002) and were then compared with the results during the period of 1996-1997 to estimate the trends and seasonal variations in concentrations of gaseous and fine particulate matter (PM2.5) principal species. Annual averages of gaseous HNO3 and NH3 increased by 11% and 6%, respectively, compared with those of the previous study, whereas HONO and SO2 decreased by 11% and 136%, respectively. The PM2.5 concentration decreased by -17%, 35% for SO4(2-), and 29% for NH4+, whereas NO3- increased by 21%. Organic carbon (OC) and elemental carbon (EC) were 12.8 and 5.98 microg/m(-3), accounting for -26 and 12% of PM2.5 concentration, respectively. The species studied accounted for 84% of PM2.5 concentration, ranging from 76% in winter to 97% in summer. Potential source contribution function (PSCF) analysis was used to identify possible source areas affecting air pollution levels at a receptor site in Seoul. High possible source areas in concentrations of PM2.5, NO3-, SO4(2-), NH4+, and K+ were coastal cities of Liaoning province (possibly emissions from oil-fired boilers on ocean liners and fishing vessels and industrial emissions), inland areas of Heibei/Shandong provinces (the highest density areas of agricultural production and population) in China, and typical port cities (Mokpo, Yeosu, and Busan) of South Korea. In the PSCF map for OC, high possible source areas were also coastal cities of Liaoning province and inland areas of Heibei/Shandong provinces in China. In contrast, high possible source areas of EC were highlighted in the south of the Yellow Sea, indicating possible emissions from oil-fired boilers on large ships between South Korea and Southeast Asia. In summary, the PSCF results may suggest that air pollution levels in Seoul are affected considerably by long-range transport from external areas, such as the coastal zone in China and other cities in South Korea, as well as Seoul itself.

Effects of downscaled high-resolution meteorological data on the PSCF identification of emission sources

DOE PAGES

Cheng, Meng -Dawn; Kabela, Erik D.

2016-04-30

The Potential Source Contribution Function (PSCF) model has been successfully used for identifying regions of emission source at a long distance in this study, the PSCF model relies on backward trajectories calculated by the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. In this study, we investigated the impacts of grid resolution and Planetary Boundary Layer (PBL) parameterization (e.g., turbulent transport of pollutants) on the PSCF analysis. The Mellor-Yamada-Janjic (MYJ) and Yonsei University (YUS) parameterization schemes were selected to model the turbulent transport in the PBL within the Weather Research and Forecasting (WRF version 3.6) model. Two separate domain grid sizesmore » (83 and 27 km) were chosen in the WRF downscaling in generating the wind data for driving the HYSPLIT calculation. The effects of grid size and PBL parameterization are important in incorporating the influ- ence of regional and local meteorological processes such as jet streaks, blocking patterns, Rossby waves, and terrain-induced convection on the transport of pollutants by a wind trajectory. We found high resolution PSCF did discover and locate source areas more precisely than that with lower resolution meteorological inputs. The lack of anticipated improvement could also be because a PBL scheme chosen to produce the WRF data was only a local parameterization and unable to faithfully duplicate the real atmosphere on a global scale. The MYJ scheme was able to replicate PSCF source identification by those using the Reanalysis and discover additional source areas that was not identified by the Reanalysis data. In conclusion, a potential benefit for using high-resolution wind data in the PSCF modeling is that it could discover new source location in addition to those identified by using the Reanalysis data input.« less

Occurrence, sources, and potential human health risks of polycyclic aromatic hydrocarbons in agricultural soils of the coal production area surrounding Xinzhou, China.

PubMed

Zhao, Long; Hou, Hong; Shangguan, Yuxian; Cheng, Bin; Xu, Yafei; Zhao, Ruifen; Zhang, Yigong; Hua, Xiaozan; Huo, Xiaolan; Zhao, Xiufeng

2014-10-01

A comprehensive investigation of the levels, distribution patterns, and sources of polycyclic aromatic hydrocarbons (PAHs) in agricultural soils of the coal production area surrounding Xinzhou, China, was conducted, and the potential human health risks associated with the levels observed were addressed. A total of 247 samples collected from agricultural soils from the area were analyzed for sixteen PAHs, including highly carcinogenic isomers. The PAH concentrations had a range of n.d. to 782ngg(-1), with a mean value of 202ngg(-1). The two-three ring PAHs were the dominant species, making up 60 percent of total PAHs. Compared with the pollution levels and carcinogenic potential risks reported in other studies, the soil PAH concentrations in the study area were in the low to intermediate range. A positive matrix factorization model indicates that coal/biomass combustion, coal and oil combustion, and coke ovens are the primary PAH sources, accounting for 33 percent, 26 percent, and 24 percent of total PAHs, respectively. The benzo[a]pyrene equivalent (BaPeq) concentrations had a range of n.d. to 476ngg(-1) for PAH7c, with a mean value of 34ngg(-1). The BaPeq concentrations of PAH7c accounted for more than 99 percent of the ∑PAH16, which suggests that seven PAHs were major carcinogenic contributors of ∑PAH16. According to the Canadian Soil Quality Guidelines, only six of the soil samples had concentrations above the safe BaPeq value of 600ngg(-1); the elevated concentrations observed at these sites can be attributed to coal combustion and industrial activities. Exposure to these soils through direct contact probably poses a significant risk to human health as a result of the carcinogenic effects of PAHs. Copyright © 2014 Elsevier Inc. All rights reserved.

Assessment of ethylene dibromide, dibromochloropropane, other volatile organic compounds, radium isotopes, radon, and inorganic compounds in groundwater and spring water from the Crouch Branch and McQueen Branch aquifers near McBee, South Carolina, 2010-2012

USGS Publications Warehouse

Landmeyer, James E.; Campbell, Bruce G.

2014-01-01

The water-quality data collected between 2010 and 2012, in conjunction with groundwater flow pathways and historical aerial photographs of land uses near McBee, indicate an area where EDB-, DBCP-, 1,2-dichloropropane-, 1,3-dichloropropane-, and carbon disulfide-contaminated groundwater exists in the Crouch Branch aquifer in the Cedar Creek Basin and north of McBee and is most likely related to the past use of these compounds between the early 1900s and the 1980s as soil fumigants in predominately agricultural areas north of McBee. The highest EDB concentration detected (18.6 micrograms per liter) during the 3-year study was in a groundwater sample from an agricultural-supply well located north of McBee. Other VOCs, such as dichloromethane and 1,1,2-trichloroethane, also were detected in groundwater samples from this EDB-contaminated agricultural-supply well but are from unknown source(s). The fact that the agricultural area north of McBee is located in a recharge area for the Crouch Branch aquifer most likely facilitated the groundwater contamination in this area. DBCP-contaminated groundwater detected in three public-supply wells south of McBee in the deeper McQueen Branch aquifer appears to be related to past soil fumigation practices that used DBCP in agricultural areas located south of McBee. One of the three DBCP-contaminated public-supply wells also contained EDB, most likely present in groundwater due to the release of leaded gasolines that contained EDB as a fuel additive between the 1940s and 1970s. A gasoline-source of EDB, rather than a soil-fumigation source, is supported by the co-detection in groundwater from the well of 1,2-dichloroethane, a lead scavenger compound also added to leaded gasoline. Groundwater pumped from two public-supply wells located within and to the east of the McBee town limits and one domestic-supply well east of McBee was characterized by the detection of 1,1-dichloroethane, trichloroethylene, 1,1-dichloroethylene, and perchloroethylene. Groundwater flow pathways determined for these wells indicate that the potential source(s) of these compounds detected in one public-supply well and the domestic-supply well may be located within the McBee town limits, and that the potential source(s) of these compounds detected in the public-supply well to the east of McBee may be located in an area north of McBee formerly used for agriculture, but used for industry since at least the 1970s. Radium isotopes (defined in this study as the sum of radium-226 and radium-228 concentrations) and radon were detected in all wells sampled in the McBee area between 2010 and 2012. Wells characterized by radium isotope concentrations in groundwater that exceeded the MCL of 5.0 picocuries per liter were also characterized by specific conductance values greater than 30 microsiemens per centimeter and clustered north of McBee in a predominately agricultural area, and in agricultural and urban areas located within and east of McBee. The elevated specific conductance values measured in groundwater from these wells most likely are due to recharge by water mineralized by fertilizer application in agricultural areas, or due to the recharge by water mineralized by septic-tank drain-field effluent near urban areas. Radon was detected in groundwater from all wells sampled, and radon concentrations in groundwater from three monitoring wells exceeded the proposed MCL of 300 picocuries per liter. Concentrations of uranium in groundwater in the McBee area increased with increased groundwater-sample depth, most likely due to the proximity of the sample-collection location to basement rock that contains uranium-bearing minerals.

Identification of groundwater nitrate sources in pre-alpine catchments: a multi-tracer approach

NASA Astrophysics Data System (ADS)

Stoewer, Myriam; Stumpp, Christine

2014-05-01

Porous aquifers in pre-alpine areas are often used as drinking water resources due to their good water quality status and water yield. Maintaining these resources requires knowledge about possible sources of pollutants and a sustainable management practice in groundwater catchment areas. Of particular interest in agricultural areas, like in pre-alpine regions, is limiting nitrate input as main groundwater pollutant. Therefore, the objective of the presented study is i) to identify main nitrate sources in a pre-alpine groundwater catchment with current low nitrate concentration using stable isotopes of nitrate (d18O and d15N) and ii) to investigate seasonal dynamics of nitrogen compounds. The groundwater catchment areas of four porous aquifers are located in Southern Germany. Most of the land use is organic grassland farming as well as forestry and residential area. Thus, potential sources of nitrate mainly are mineral fertilizer, manure/slurry, leaking sewage system and atmospheric deposition of nitrogen compounds. Monthly freshwater samples (precipitation, river water and groundwater) are analysed for stable isotope of water (d2H, d18O), the concentration of major anions and cations, electrical conductivity, water temperature, pH and oxygen. In addition, isotopic analysis of d18O-NO3- and d15N-NO3- for selected samples is carried out using the denitrifier method. In general, all groundwater samples were oxic (10.0±2.6mg/L) and nitrate concentrations were low (0.2 - 14.6mg/L). The observed nitrate isotope values in the observation area compared to values from local precipitation, sewage, manure and mineral fertilizer as well as to data from literature shows that the nitrate in freshwater samples is of microbial origin. Nitrate derived from ammonium in fertilizers and precipitation as well as from soil nitrogen. It is suggested that a major potential threat to the groundwater quality is ammonia and ammonium at a constant level mainly from agriculture activities as well as continuously release of nitrogen stored in agricultural soils due to mineralization processes. In all groundwater and river water samples a seasonal variation of nitrate sources and concentration is absent but nitrate in precipitation shows a clear seasonal variation with peaks in spring and fall according to agricultural activity. This points to dilution effects of high nitrate inputs due to the large groundwater volume and mean residence time and highlights the function of soil as initial sink for nitrogen compounds delivered by fertilizer. Even though nitrate contamination was low in the study area, the results emphasize the importance of reducing additional nitrate sources in pre-alpine oxic aquifers. This will maintain the good water quality status of the aquifers and enable its use for drinking water supply.

Biogas Potential on Long Island, New York: A Quantification Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahajan, D.; Patel, S.; Tonjes, D.

2011-08-25

Biogas is the product of anaerobic digestion of waste, whether occurring spontaneously in landfills or under controlled conditions in digesters. Biogas is viewed as an important energy source in current efforts to reduce the use of fossil fuels and dependency on imported resources. Several studies on the assessment of biogas potential have been made at regional, national, and global scales. However, because it is not economically feasible to transport biogas feedstock over long distances, it is more appropriate to consider local waste sources for their potential to produce biogas. An assessment of the biogas potential on Long Island, based onmore » the review of local landfills, wastewater treatment plants, solid waste generation and management, and agricultural waste, found that 234 x 10{sup 6} m{sup 3} of methane (CH{sub 4}) from biogas might be harvestable, although substantial barriers for complete exploitation exist. This number is equivalent to 2.52 TW-h of electricity, approximately 12% of fossil fuel power generation on Long Island. This work can serve as a template for other areas to rapidly create or approximate biogas potentials, especially for suburban U.S. locations that are not usually thought of as sources of renewable energy.« less

A high brightness source for nano-probe secondary ion mass spectrometry

NASA Astrophysics Data System (ADS)

Smith, N. S.; Tesch, P. P.; Martin, N. P.; Kinion, D. E.

2008-12-01

The two most prevalent ion source technologies in the field of surface analysis and surface machining are the Duoplasmatron and the liquid metal ion source (LMIS). There have been many efforts in this area of research to develop an alternative source [ S.K. Guharay, J. Orloff, M. Wada, IEEE Trans. Plasma Sci. 33 (6) (2005) 1911; N.S. Smith, W.P. Skoczylas, S.M. Kellogg, D.E. Kinion, P.P. Tesch, O. Sutherland, A. Aanesland, R.W. Boswell, J. Vac. Sci. Technol. B 24 (6) (2006) 2902-2906] with the brightness of a LMIS and yet the ability to produce secondary ion yield enhancing species such as oxygen. However, to date a viable alternative has not been realized. The high brightness and small virtual source size of the LMIS are advantageous for forming high resolution probes but a significant disadvantage when beam currents in excess of 100 nA are required, due to the effects of spherical aberration from the optical column. At these higher currents a source with a high angular intensity is optimal and in fact the relatively moderate brightness of today's plasma ion sources prevail in this operating regime. Both the LMIS and Duoplasmatron suffer from a large axial energy spread resulting in further limitations when forming focused beams at the chromatic limit where the figure-of-merit is inversely proportional to the square of the energy spread. Also, both of these ion sources operate with a very limited range of ion species. This article reviews some of the latest developments and some future potential in this area of instrument development. Here we present an approach to source development that could lead to oxygen ion beam SIMS imaging with 10 nm resolution, using a 'broad area' RF gas phase ion source.

Assessment of groundwater vulnerability to nitrates from agricultural sources using a GIS-compatible logic multicriteria model.

PubMed

Rebolledo, Boris; Gil, Antonia; Flotats, Xavier; Sánchez, José Ángel

2016-04-15

In the present study an overlay method to assess groundwater vulnerability is proposed. This new method based on multicriteria decision analysis (MCDA) was developed and validated using an appropriate case study in Aragon area (NE Spain). The Vulnerability Index to Nitrates from Agricultural Sources (VINAS) incorporates a novel Logic Scoring of Preferences (LSP) approach, and it has been developed using public geographic information from the European Union. VINAS-LSP identifies areas with five categories of vulnerability, taking into account the hydrogeological and environmental characteristics of the territory as a whole. The resulting LSP map is a regional screening tool that can provide guidance on the potential risk of nitrate pollution, as well as highlight areas where specific research and farming planning policies are required. Copyright © 2016 Elsevier Ltd. All rights reserved.

Combining measurements and modelling to quantify the contribution of atmospheric fallout, local industry and road traffic to PAH stocks in contrasting catchments.

PubMed

Gateuille, David; Evrard, Olivier; Lefevre, Irène; Moreau-Guigon, Elodie; Alliot, Fabrice; Chevreuil, Marc; Mouchel, Jean-Marie

2014-06-01

Various sources supply PAHs that accumulate in soils. The methodology we developed provided an evaluation of the contribution of local sources (road traffic, local industries) versus remote sources (long range atmospheric transport, fallout and gaseous exchanges) to PAH stocks in two contrasting subcatchments (46-614 km²) of the Seine River basin (France). Soil samples (n = 336) were analysed to investigate the spatial pattern of soil contamination across the catchments and an original combination with radionuclide measurements provided new insights into the evolution of the contamination with depth. Relationships between PAH concentrations and the distance to the potential sources were modelled. Despite both subcatchments are mainly rural, roadside areas appeared to concentrate 20% of the contamination inside the catchment while a local industry was found to be responsible for up to 30% of the stocks. Those results have important implications for understanding and controlling PAH contamination in rural areas of early-industrialized regions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of plasma grid bias on extracted currents in the RF driven surface-plasma negative ion source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belchenko, Yu., E-mail: belchenko@inp.nsk.su; Ivanov, A.; Sanin, A.

2016-02-15

Extraction of negative ions from the large inductively driven surface-plasma negative ion source was studied. The dependencies of the extracted currents vs plasma grid (PG) bias potential were measured for two modifications of radio-frequency driver with and without Faraday screen, for different hydrogen feeds and for different levels of cesium conditioning. The maximal PG current was independent of driver modification and it was lower in the case of inhibited cesium. The maximal extracted negative ion current depends on the potential difference between the near-PG plasma and the PG bias potentials, while the absolute value of plasma potential in the drivermore » and in the PG area is less important for the negative ion production. The last conclusion confirms the main mechanism of negative ion production through the surface conversion of fast atoms.« less

Can inbound and domestic medical tourism improve your bottom line? Identifying the potential of a U.S. tourism market.

PubMed

Fottler, Myron D; Malvey, Donna; Asi, Yara; Kirchner, Sarah; Warren, Natalia A

2014-01-01

In large part due to current economic conditions and the political uncertainties of healthcare reform legislation, hospitals need to identify new sources of revenue. Two potentially untapped sources are inbound (international) and domestic (within the United States) medical tourists. This case study uses data from a large, urban healthcare system in the southeastern United States to quantify its potential market opportunities for medical tourism. The data were mined from electronic health records, and descriptive frequency analysis was used to provide a preliminary market assessment. This approach permits healthcare systems to move beyond anecdotal information and assess the relative market potential of their particular geographic area and the diagnostic services they offer for attracting inbound and domestic medical tourists. Implications for healthcare executives and guidance on how they can focus marketing efforts are discussed.

The engagement of cortical areas preceding exogenous vergence eye movements.

PubMed

Wojtczak-Kwaśniewska, Monika; Przekoracka-Krawczyk, Anna; Van der Lubbe, Rob H J

2018-01-01

Source analyses on event related potentials (ERPs) derived from the electroencephalogram (EEG) were performed to examine the respective roles of cortical areas preceding exogenously triggered saccades, combined convergences, and combined divergences. All eye movements were triggered by the offset of a central fixation light emitting diode (LED) and the onset of a lateral LED at various depths in an otherwise fully darkened room. Our analyses revealed that three source pairs, two located in the frontal lobe-the frontal eye fields (FEF) and an anterior frontal area-, and one located within the occipital cortex, can account for 99.2% of the observed ERPs. Overall, the comparison between source activities revealed the largest activity in the occipital cortex, while no difference in activity between FEF and the anterior frontal area was obtained. For all sources, increased activity was observed for combined vergences, especially combined convergences, relative to saccades. Behavioral results revealed that onset latencies were longest for combined convergences, intermediate for combined divergences, and the shortest for saccades. Together, these findings fit within a perspective in which both occipital and frontal areas play an important role in retinal disparity detection. In the case of saccades and combined divergences stimulus-locked activity was larger than response-locked activity, while no difference between stimulus- and response-locked activity was observed for combined convergences. These findings seem to imply that the electrophysiological activity preceding exogenous eye movements consists of a sensory-related part that is under cortical control, while subcortical structures may be held responsible for final execution.

Current and new developments in transport and regulatory issues concerning radioisotopes: managing change for minimum business impact

NASA Astrophysics Data System (ADS)

Bennett, Neil; Coppell, David; Rogers, David; Schrader, John

2004-09-01

Changes in the regulatory framework governing the Radiation Processing Industry have the potential to make a real business impact on day-to-day profitability. Many areas of the Radiation Processing Industry are affected by changes in the regulatory framework within which these areas are managed. When planning for such changes the transportation element in the shipment of sealed cobalt radiation sources is an area that is often neglected by some parts of the distribution chain. A balance must be struck between the cobalt supplier and the facility operator/customer that rests upon how much the customer needs to know about the intricacies of cobalt shipment. The objective of this paper is to highlight areas of possible business impact and reassure the users of sealed radiation sources that the global suppliers of these products are used to negotiating local variations in regulations governing the physical transportation of radiation sources, changes in regulations governing the design, manufacture and use of transportation containers and changes in the availability of commercial shippers and shipping routes. The major suppliers of industrial quantities of cobalt-60 are well placed to lead their customers through this complex process as a matter of routine.

Superfund Record of Decision (EPA Region 6): Cimarron Mining Corporation site, Operable Unit 1, Lincoln County, Carrizozo, NM. (First remedial action), September 1990

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1990-09-21

The 10.6-acre Cimarron Mining site, Lincoln County, New Mexico, is an inactive milling facility used to recover iron from ores transported to the site. A shallow aquifer, which is not a potential drinking water source, and a deeper primary drinking water aquifer lie beneath the site. Cyanide was used until 1982 to recover precious metals. The operation of the mill resulted in the discharge of contaminated liquids onsite. The sources of environmental cyanide contamination at the site are the processed waste materials, including tailings piles and cinder block trench sediment piles, the cyanide solution and tailings spillage areas, and themore » cyanide solution recycling and disposal areas, including cinder block trenches and an unlined discharge pit. The major sources of ground water contamination by cyanide are the cinder block trenches and the discharge pit. These areas of prolonged contact between cyanide solution and underlying soil led to cyanide contamination in the shallow aquifer. The ROD addresses contaminated shallow ground water at the Cimarron Mining mill area as Operable Unit 1 (OU1). The primary contaminants of concern affecting the ground water are inorganics including cyanide.« less

Isotopic Discrimination of Perchlorate Sources in Ground Water

NASA Astrophysics Data System (ADS)

Bohlke, J.; Hatzinger, P. B.; Sturchio, N. C.; Gu, B.; Jackson, W. A.; Abbene, I. J.

2007-12-01

Perchlorate has been detected in ground water and drinking water in many areas of the U.S. during the past decade. Sources of potential perchlorate enrichment in ground water include releases from past military activities, fireworks manufacture and display, fertilizer applications, discarded road flares, and local atmospheric deposition. Here we present analyses of stable isotopes (δ37Cl, δ18O, and Δ17O) of dissolved perchlorate, along with other supporting environmental tracer data, from selected occurrences in ground water in the U.S. The isotope data indicate that both synthetic and natural perchlorate are present in ground water, and that multiple sources are present locally in some areas. The sampled ground waters generally were oxic and the perchlorate isotopes generally were not affected substantially by biodegradation. In some areas, natural perchlorate, with Δ17O = +7 to +10 ‰, can be attributed to agricultural applications of atmospherically derived natural nitrate fertilizer imported from South America (Atacama Desert, Chile). In at least one agricultural area in New York, concentrations of perchlorate increase with depth and ground-water age, possibly because of decreasing application rates of Atacama nitrate fertilizer and(or) decreasing perchlorate concentrations in the imported fertilizer products in recent years.

Electron beam extraction on plasma cathode electron sources system

NASA Astrophysics Data System (ADS)

Purwadi, Agus; Taufik, M., Lely Susita R.; Suprapto, Saefurrochman, H., Anjar A.; Wibowo, Kurnia; Aziz, Ihwanul; Siswanto, Bambang

2017-03-01

ELECTRON BEAM EXTRACTION ON PLASMA CATHODE ELECTRON SOURCES SYSTEM. The electron beam extraction through window of Plasma Generator Chamber (PGC) for Pulsed Electron Irradiator (PEI) device and simulation of plasma potential has been studied. Plasma electron beam is extracted to acceleration region for enlarging their power by the external accelerating high voltage (Vext) and then it is passed foil window of the PEI for being irradiated to any target (atmospheric pressure). Electron beam extraction from plasma surface must be able to overcome potential barrier at the extraction window region which is shown by estimate simulation (Opera program) based on data of plasma surface potential of 150 V with Ueks values are varied by 150 kV, 175 kV and 200 kV respectively. PGC is made of 304 stainless steel with cylindrical shape in 30 cm of diameter, 90 cm length, electrons extraction window as many as 975 holes on the area of (15 × 65) cm2 with extraction hole cell in 0.3 mm of radius each other, an cylindrical shape IEP chamber is made of 304 stainless steel in 70 cm diameter and 30 cm length. The research result shown that the acquisition of electron beam extraction current depends on plasma parameters (electron density ne, temperature Te), accelerating high voltage Vext, the value of discharge parameter G, anode area Sa, electron extraction window area Se and extraction efficiency value α.

A systemic ecological risk assessment based on spatial distribution and source apportionment in the abandoned lead acid battery plant zone, China.

PubMed

Zhang, Yimei; Li, Shuai; Chen, Zhuang; Wang, Fei; Chen, Jie; Wang, Liqun

2018-07-15

In China, potential heavy metal hazard around abandoned lead-acid battery plant (ALBP) area has been a great concern but without detailed report. The distribution and sources of heavy metals in soils and so by risk assessment associated with ALBP are conducted in this contribution, based on geographies and statistics. Pb and Zn are quantitively identified to be still emitted from ALBP soil, and Cd as well As are from agricultural activity. We investigate vertical metal distribution, and fortunately find that metals migrate within limit of 40 cm below topsoil, which is higher than groundwater table. The visualized stable depths are Zn 40 cm, Pb, As 20 cm, and Cd 40 cm. The mapped pollution load index (PLI) suggests a high pollution level exists in ALBP soil. The estimation of potential ecological risk index (PERI) indicates a light ecological risk in studied area, while As and Cd mainly from agricultural activity possess 54% of total E ri . Health risk index (THI) is 0.178 for children, indicating non-cancer risks may be ignored in observed area. Though calculated risk is temporarily affordable, soil remediation and reduction of agricultural chemical reagents are recommended for preventing potential cumulative risk from further bioconcentration of heavy metals. Copyright © 2018 Elsevier B.V. All rights reserved.

Sediment sources in a small agricultural catchment: A composite fingerprinting approach based on the selection of potential sources

NASA Astrophysics Data System (ADS)

Zhou, Huiping; Chang, Weina; Zhang, Longjiang

2016-08-01

Fingerprinting techniques have been widely used as a reasonable and reliable means for investigating sediment sources, especially in relatively large catchments in which there are significant differences in surface materials. However, the discrimination power of fingerprint properties for small catchments, in which the surface materials are relatively homogeneous and human interference is marked, may be affected by fragmentary or confused source information. Using fingerprinting techniques can be difficult, and there is still a need for further studies to verify the effectiveness of such techniques in these small catchments. A composite fingerprinting approach was used in this study to investigate the main sources of sediment output, as well as their relative contributions, from a small catchment (30 km2) with high levels of farming and mining activities. The impact of the selection of different potential sediment sources on the derivation of composite fingerprints and its discrimination power were also investigated by comparing the results from different combinations of potential source types. The initial source types and several samples that could cause confusion were adjusted. These adjustments improved the discrimination power of the composite fingerprints. The results showed that the composite fingerprinting approach used in this study had a discriminatory efficiency of 89.2% for different sediment sources and that the model had a mean goodness of fit of 0.90. Cultivated lands were the main sediment source. The sediment contribution of the studied cultivated lands ranged from 39.9% to 87.8%, with a mean of 76.6%, for multiple deposited sediment samples. The mean contribution of woodlands was 21.7%. Overall, the sediment contribution from mining and road areas was relatively low. The selection of potential sources is an important factor in the application of fingerprinting techniques and warrants more attention in future studies, as is the case with other uncertainty factors.

Susceptibility of ground water to surface and shallow sources of contamination, Orange County, North Carolina

USGS Publications Warehouse

Terziotti, Silvia; Eimers, J.L.

1999-01-01

In 1998, the relative susceptibility of ground water in Orange County, North Carolina,to contamination from surface and shallow sources was evaluated. A geographic information system was used to build three county-wide layers--soil permeability, land use/land cover, and land-surface slope. The harmonic mean permeability of soil layers was used to estimate a location's capacity to transmit water through the soil. Values for each of these three factors were categorized and ranked from 1 to 10 according to relative potential for contamination. Each factor was weighted to reflect its relative potential contribution to ground-water contamination, then the factors were combined to create a relative susceptibility index. The relative susceptibility index was categorized to reflect lowest, low, moderate, high, and highest potential for ground-water contamination. The relative susceptibility index for about 12 percent of the area in Orange County was categorized as high or highest. The high and highest range areas have highly permeable soils, land cover or land-use activities that have a high contamination potential, and low to moderate slopes. Most of the county is within the moderate category of relative susceptibility to ground-water contamination. About 21 percent of the county is ranked as low or lowest relative susceptibility to ground-water contamination.

CHEMICAL CONTAMINATION AND TOXICITY ASSOCIATED WITH A COASTAL GOLF COURSE COMPLEX

EPA Science Inventory

The increasing density of golf courses represents a potential source of contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to compare the concentrations of contaminants and toxicities of sedime...

SEDIMENT CHEMICAL CONTAMINATION AND TOXICITY ASSOCIATED WITH A COASTAL GOLF COURSE COMPLEX.

EPA Science Inventory

The increasing density of golf courses represents a potential source of sediment contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to determine the concentrations of contaminants and toxicities...

EXAMINATION OF BOTTLED WATER FOR NONTUBERCULOUS MYCOBACTERIA

EPA Science Inventory

The objective of this study was to examine bottled water for the presence of nontuberculous mycobacteria as a potential source of infection in AIDS patients. Twenty brands of bottled water commonly used in the Los Angeles area were tested for the presence of nontuberculous mycoba...

75 FR 71643 - Periodic Reporting Rules

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-24

... on one-time studies. 2. Mail processing is the largest source of volume-variable costs in the postal... a strategic rulemaking, identifies several potential areas for study, and seeks suggestions for... data collection programs that need to be established. It might list existing analytical studies that...

T Is for Temporary.

ERIC Educational Resources Information Center

Pontau, Donna Zufan; Rothschild, M. Cecilia

1986-01-01

Discusses four potential problem areas in the employment of temporary librarians in a variety of positions in academic libraries--orientation, supervision, acceptance and integration, and utilization--and notes the influence of time limitations on the work environment. Solutions are suggested, and further research is proposed. Fourteen sources are…

The Jordan River: Source of Life and Source of Conflict

DTIC Science & Technology

2010-03-01

potential conflict begin almost where the Jordan River itself begins – at it headwaters in Lebanon, in the northwest quadrant of the Jordan River...essentially focuses attention on the tension between Israel and Syria, in the northeast quadrant of the Jordan River basin. This is an area where mainly...34 Foreign Policy, no. 54 (1984): 3-26. 23 Arnold Hottinger, “Wasser als Konfliktstoff: Eine Existenzfrage für Staaten des Nahen Ostens,” Europa

Vernonia galamensis, potential new crop source of epoxy acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perdue, R.E. Jr.; Carlson, K.D.; Gilbert, M.G.

Vernonia galamensis is a good source of seed oil rich in epoxy acid, which can be used to manufacture plastic formulations, protective coatings, and other products. Seed from a natural stand in Ethiopia contained 31% epoxy acid. Under cultivation in Kenya, this unimproved germ plasm produced a substantial yield of seed with 32% epoxy acid. This African species has good natural seed retention and is a promising new crop for semiarid tropical areas. 11 references.

Frequency domain measurement systems

NASA Technical Reports Server (NTRS)

Eischer, M. C.

1978-01-01

Stable frequency sources and signal processing blocks were characterized by their noise spectra, both discrete and random, in the frequency domain. Conventional measures are outlined, and systems for performing the measurements are described. Broad coverage of system configurations which were found useful is given. Their functioning and areas of application are discussed briefly. Particular attention is given to some of the potential error sources in the measurement procedures, system configurations, double-balanced-mixer-phase-detectors, and application of measuring instruments.

Cooper Lake and Channels, Texas. Supplement.

DTIC Science & Technology

1977-06-24

subject to the Red River compact, which is an agreement between the States of Arkansas, Oklahoma, Louisiana , and Texas concerning the water in the Red River ...new reservoir sites, and ground water 26 ;’ i - -- " ... sources. The geographical area considered was the lower section of the Red River Basin, the...Cooper Lake site. Two potential sources of water supply in the Red River Basin were considered in more detail. One would be to divert water from the

Contamination characteristics and source apportionment of heavy metals in topsoil from an area in Xi'an city, China.

PubMed

Chen, Xiuduan; Lu, Xinwei

2018-04-30

As soil-extractable elements potentially pose ecological and health risks, identifying their contamination characteristics and sources is crucial. Therefore, to understand topsoil trace elements in the urban ring zone from the Second Ring Road to the Third Ring of Xi'an city in China, we determined the concentrations of Zn, Co, V, As, Cu, Mn, Ba, Ni and Pb, and analyzed the sources of the contamination. The results showed that the individual pollution indices of Pb, Co, Cu, Zn, Ba, Ni, Mn, As, and V were 1.79, 1.48, 1.41, 1.33, 1.20, 1.07, 1.04, 0.99, and 0.99, respectively. Evaluation with the aid of the pollution load index (PLI) indicated slight soil contamination by these elements in the study area. Using the positive matrix factorization (PMF) method, we identified four sources of contamination, namely (1) a natural source, (2) traffic emission source, (3) industrial emission source, and (4) mixed source. PMF is an effective tool for source apportionment of heavy metals in topsoil. The contribution rates of the natural source, traffic source, mixed source, and industrial source to the heavy metal contamination were specified as 25.04%, 24.71%, 24.99%, and 25.26%, respectively. Considering the above, any attempt to reduce the soil environmental cost of urban development, has to take into account the heavy metal contamination of the topsoil from industries, traffic, and other activities. Copyright © 2018 Elsevier Inc. All rights reserved.

Assessment of the Distribution, Sources and Potential Ecological Risk of Heavy Metals in the Dry Surface Sediment of Aibi Lake in Northwest China

PubMed Central

Abuduwaili, Jilili; Zhang, Zhao yong; Jiang, Feng qing

2015-01-01

The distribution, sources and potential ecological risk of heavy metals in the sediment of lakes in eastern China and other areas of the world that have undergone rapid economic development have been widely researched by scholars. However, this is not true for heavy metals in the sediment of rump lakes in the arid regions of China and world-wide. Because of this, we chose Aibi Lake to serve as a typical rump lake in an oasis in an arid area in northwest China for our study. Sediment samples were collected from the lake and then the quantities of the heavy metals Pb, Ni, Cd, Cu, Zn, Hg and Cr were measured. Then using a variety of statistical methods, we analyzed the distribution, sources, pollution status and the potential ecological risk of these metals. The results show that: (1) The amounts of the seven heavy metals all fell within the Second Soil National Standard, but the average and maximum values were all higher than the background values of Xinjiang in northwest China. (2) Multivariate statistical analysis determined that the Cd, Pb, Hg and Zn in the sediment were mainly derived from man-sources, and Cu, Ni, and Cr were mainly from the natural geological background. (3) Enrichment factor analysis and the geo-accumulation index evaluation method show that Cd, Hg and Pb in the surface sediment of the Aibi Lake were at low and partial pollution levels, while Zn, Cr, Ni and Cu were at no and low pollution levels. (4) Calculation of the potential ecological hazards index found that, among the seven tested heavy metals, Cd, Hg and Pb were the main potential ecological risk factors, and the contribution of each was 42.6%, 28.6%, and 24.0%, respectively. Cd is the main potential ecological risk factor, followed by Hg and Pb. This work revealed that recent economic development of the Aibi Lake Basin has negatively influenced the accumulation of heavy metals in the sediments of the lake, and, therefore, we should pay increasing attention to this problem and take effective measures to protect the ecology of the Aibi Lake Basin. This work can provide a scientific basis for an early warning of heavy metal pollution and for protection of the environment. Furthermore, it can serve as a reference when creating policies for the economic development in Aibi Lake Basin and environmental protection of rump lakes in arid regions of northwest China and other areas of the world. PMID:25781032

Methane source identification in Boston, Massachusetts using isotopic and ethane measurements

NASA Astrophysics Data System (ADS)

Down, A.; Jackson, R. B.; Plata, D.; McKain, K.; Wofsy, S. C.; Rella, C.; Crosson, E.; Phillips, N. G.

2012-12-01

Methane has substantial greenhouse warming potential and is the principle component of natural gas. Fugitive natural gas emissions could be a significant source of methane to the atmosphere. However, the cumulative magnitude of natural gas leaks is not yet well constrained. We used a combination of point source measurements and ambient monitoring to characterize the methane sources in the Boston urban area. We developed distinct fingerprints for natural gas and multiple biogenic methane sources based on hydrocarbon concentration and isotopic composition. We combine these data with periodic measurements of atmospheric methane and ethane concentration to estimate the fractional contribution of natural gas and biogenic methane sources to the cumulative urban methane flux in Boston. These results are used to inform an inverse model of urban methane concentration and emissions.

Nutrients in waters on the inner shelf between Cape Charles and Cape Hatteras

NASA Technical Reports Server (NTRS)

Wong, G. T. F.; Todd, J. F.

1981-01-01

The distribution of nutrients in the shelf waters of the southern tip of the Middle Atlantic Bight was investigated. It is concluded that the outflow of freshwater from the Chesapeake Bay is a potential source of nutrients to the adjacent shelf waters. However, a quantitative estimation of its importance cannot yet be made because (1) there are other sources of nutrients to the study area and these sources cannot yet be quantified and (2) the concentrations of nutrients in the outflow from Chesapeake Bay exhibit significant short-term and long-term temporal variabilities.

Remote sensing applied to prospecting of thermomineral water in the county of Caldas Novas-Goias

NASA Technical Reports Server (NTRS)

Veneziani, P.; Eustaquiodosanjos, C.

1978-01-01

LANDSAT imagery of the region were studied allowing the placement of the area of study in the regional geological context. A geological mapping of the 1.60.000 scale was done. A methodology was developed which consisted in a regional temperature mapping using trend surface analysis. Through the correlation of all these data, four different areas were localized with a high potential as thermomineral sources.

Groundwater vulnerability assessment for organic compounds: fuzzy multi-criteria approach for Mexico city.

PubMed

Mazari-Hiriart, Marisa; Cruz-Bello, Gustavo; Bojórquez-Tapia, Luis A; Juárez-Marusich, Lourdes; Alcantar-López, Georgina; Marín, Luis E; Soto-Galera, Ernesto

2006-03-01

This study was based on a groundwater vulnerability assessment approach implemented for the Mexico City Metropolitan Area (MCMA). The approach is based on a fuzzy multi-criteria procedure integrated in a geographic information system. The approach combined the potential contaminant sources with the permeability of geological materials. Initially, contaminant sources were ranked by experts through the Analytic Hierarchy Process. An aggregated contaminant sources map layer was obtained through the simple additive weighting method, using a scalar multiplication of criteria weights and binary maps showing the location of each source. A permeability map layer was obtained through the reclassification of a geology map using the respective hydraulic conductivity values, followed by a linear normalization of these values against a compatible scale. A fuzzy logic procedure was then applied to transform and combine the two map layers, resulting in a groundwater vulnerability map layer of five classes: very low, low, moderate, high, and very high. Results provided a more coherent assessment of the policy-making priorities considered when discussing the vulnerability of groundwater to organic compounds. The very high and high vulnerability areas covered a relatively small area (71 km(2) or 1.5% of the total study area), allowing the identification of the more critical locations. The advantage of a fuzzy logic procedure is that it enables the best possible use to be made of the information available regarding groundwater vulnerability in the MCMA.

A review of the economic implications of the National Academy of Engineering 1974 study of the potential application of space systems

NASA Technical Reports Server (NTRS)

1975-01-01

User benefits resulting from the application of space systems to previously described application areas were identified, and methods to assign priorities to application areas and to quantify the benefits were described. The following areas were selected for in-depth review: communications, materials processing in space, weather and climate, and institutional arrangements for space applications. Recommendations concerning studies that should be undertaken to develop a more precise understanding of the source and magnitude of the realizable economic benefits were also presented.

TA-60-1 Heavy Equipment Shop Areas SWPPP Rev 2 Jan 2017-Final

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burgin, Jillian Elizabeth

The primary activities and equipment areas at the facility that are potential stormwater pollution sources include; The storage of vehicles and heavy equipment awaiting repair; or repaired vehicles waiting to be picked up; The storage and handling of oils, anti-freeze, solvents, degreasers, batteries and other chemicals for the maintenance of vehicles and heavy equipment; and Equipment cleaning operations including exterior vehicle wash-down. Steam cleaning is only done on the steam cleaning pad area located at the north east end of Building 60-0001.

Influence of basements, garages, and common hallways on indoor residential volatile organic compound concentrations

NASA Astrophysics Data System (ADS)

Dodson, Robin E.; Levy, Jonathan I.; Spengler, John D.; Shine, James P.; Bennett, Deborah H.

Concentrations of many volatile organic compounds (VOCs) are often higher inside residences than outdoors as a result of sources or activities within the residences. These sources can be located directly in the living space of the home or in areas associated with the home such as an attached garage, basement, or common apartment hallway. To characterize the contributions from these areas to indoor residential concentrations, VOC concentrations were measured inside, outside, and, if present, in the attached garage, basement, or common hallway of an apartment of 55 residences in the Boston area, most over two seasons, as part of the Boston Exposure Assessment in Microenvironments (BEAM) Study. Of the 55 residences in the study, 11 had attached garages and basements, 24 had only basements, 10 other residences had common apartment hallways, and the remaining 10 were treated as single compartment residences. Concentrations in the garage were up to 5-10 times higher at the median than indoor concentrations for mobile source pollutants including benzene, toluene, ethylbenzene, and xylenes. Basement/indoor concentration ratios were significantly >1 for methylene chloride, ethylbenzene, m, p-xylene, and o-xylene, and summer ratios tended to be higher than winter ratios. Approximately, 20-40% of the indoor concentration for compounds associated with gasoline sources, such as methyl t-butyl ether (MTBE), benzene, toluene, ethylbenzene, and xylenes, can be attributed to an attached garage at the residence, with garages laterally attached to the first floor of the home having a larger impact. At the median, basements contributed to approximately 10-20% of the estimated indoor concentrations. For apartments, approximately 5-10% of the estimated indoor concentrations confer with air from the hallway. Contributions of these secondary zones to concentrations in the living area of a home were calculated using concentration and airflow estimates. Our findings illustrate the potential significance of these non-living spaces from an exposure perspective and suggest potentially effective mitigation measures.

Decadal-scale changes in dissolved-solids concentrations in groundwater used for public supply, Salt Lake Valley, Utah

USGS Publications Warehouse

Thiros, Susan A.; Spangler, Larry

2010-01-01

Basin-fill aquifers are a major source of good-quality water for public supply in many areas of the southwestern United States and have undergone increasing development as populations have grown over time. During 2005, the basin-fill aquifer in Salt Lake Valley, Utah, provided approximately 75,000 acre-feet, or about 29 percent of the total amount of water used by a population of 967,000. Groundwater in the unconsolidated basin-fill deposits that make up the aquifer occurs under unconfined and confined conditions. Water in the shallow unconfined part of the groundwater system is susceptible to near-surface contamination and generally is not used as a source of drinking water. Groundwater for public supply is withdrawn from the deeper unconfined and confined parts of the system, termed the principal aquifer, because yields generally are greater and water quality is better (including lower dissolved-solids concentrations) than in the shallower parts of the system. Much of the water in the principal aquifer is derived from recharge in the adjacent Wasatch Range (mountain-block recharge). In many areas, the principal aquifer is separated from the overlying shallow aquifer by confining layers of less permeable, fine-grained sediment that inhibit the downward movement of water and any potential contaminants from the surface. Nonetheless, under certain hydrologic conditions, human-related activities can increase dissolved-solids concentrations in the principal aquifer and result in groundwater becoming unsuitable for consumption without treatment or mixing with water having lower dissolved-solids concentrations. Dissolved-solids concentrations in areas of the principal aquifer used for public supply typically are less than 500 milligrams per liter (mg/L), the U.S. Environmental Protection Agency (EPA) secondary (nonenforceable) drinking-water standard. However, substantial increases in dissolved-solids concentrations in the principal aquifer have been documented in some areas used for public supply, raising concerns as to the source(s) and cause(s) of the higher concentrations and the potential long-term effects on groundwater quality.

Hydrocarbon Reservoir Identification in Volcanic Zone by using Magnetotelluric and Geochemistry Information

NASA Astrophysics Data System (ADS)

Firda, S. I.; Permadi, A. N.; Supriyanto; Suwardi, B. N.

2018-03-01

The resistivity of Magnetotelluric (MT) data show the resistivity mapping in the volcanic reservoir zone and the geochemistry information for confirm the reservoir and source rock formation. In this research, we used 132 data points divided with two line at exploration area. We used several steps to make the resistivity mapping. There are time series correction, crosspower correction, then inversion of Magnetotelluric (MT) data. Line-2 and line-3 show anomaly geological condition with Gabon fault. The geology structure from the resistivity mapping show the fault and the geological formation with the geological rock data mapping distribution. The geochemistry information show the maturity of source rock formation. According to core sample analysis information, we get the visual porosity for reservoir rock formation in several geological structure. Based on that, we make the geological modelling where the potential reservoir and the source rock around our interest area.

A pH sensor based on electric properties of nanotubes on a glass substrate

PubMed Central

Nakamura, Motonori; Ishii, Atsushi; Subagyo, Agus; Hosoi, Hirotaka; Sueoka, Kazuhisa; Mukasa, Koichi

2007-01-01

We fabricated a pH-sensitive device on a glass substrate based on properties of carbon nanotubes. Nanotubes were immobilized specifically on chemically modified areas on a substrate followed by deposition of metallic source and drain electrodes on the area. Some nanotubes connected the source and drain electrodes. A top gate electrode was fabricated on an insulating layer of silane coupling agent on the nanotube. The device showed properties of ann-type field effect transistor when a potential was applied to the nanotube from the top gate electrode. Before fabrication of the insulating layer, the device showed that thep-type field effect transistor and the current through the source and drain electrodes depend on the buffer pH. The current increases with decreasing pH of the CNT solution. This device, which can detect pH, is applicable for use as a biosensor through modification of the CNT surface. PMID:21806848

Potential impacts of a changing Arctic on community water sources on the Seward Peninsula, Alaska

NASA Astrophysics Data System (ADS)

Chambers, Molly; White, Daniel; Busey, Robert; Hinzman, Larry; Alessa, Lilian; Kliskey, Andrew

2007-12-01

This paper discusses the potential impacts of climate change on community drinking water sources on the Seward Peninsula. The vulnerability assessment was largely based on the likelihood that the water source would be impacted by a change in the permafrost regime. Factors that were considered were the likely change in the permafrost condition of a watershed, the watershed area, and the contribution of groundwater to streamflow. Results showed that the change in permafrost condition is likely to impact some communities much more than others, even though the communities are near to each other. Communities that will experience little change to the permafrost in their watersheds, have a significant contribution of base flow to their streams and rivers, or have water sources with large watersheds were not found to be vulnerable. On the other hand, communities with small watersheds, watersheds that were likely to see a significant change in the permafrost regime, or watersheds with little winter base flow were seen to be vulnerable to climate change. The results of this work could be valuable to community leadership when considering future vulnerability. The same approach could be used across the Arctic to assess the potential impact of climate change on community water sources and ultimate sustainability.

The environmental balance of the Alta Val d'Agri: a contribution to the evaluation of the industrial risk and strategic sustainable development

NASA Astrophysics Data System (ADS)

Loperte, S.; Cosmi, C.

2015-09-01

This study presents the preliminary environmental balance of the Alta Val d'Agri (Basilicata Region, Southern Italy), an area of great naturalistic interest characterized by the presence of huge oil and gas fields. The Driving Forces-Pressure-State-Impact-Responses (DPSIR) methodology was used to outline the background in terms of environmental impacts mainly caused by oil extraction activities, as well as potential existing responses. The study aims at providing stakeholders with an exhaustive framework to identify the existing data, the main sources of pollution, their potential impacts, the associated industrial risks and the existing policy strategies. Moreover, the DPSIR approach allows the identification of the vulnerable areas and the definition of targeted actions for a sustainable development of the area.

Sources of heavy metal pollution in agricultural soils of a rapidly industrializing area in the Yangtze Delta of China.

PubMed

Xu, Xianghua; Zhao, Yongcun; Zhao, Xiaoyan; Wang, Yudong; Deng, Wenjing

2014-10-01

The rapid industrialization and urbanization in developing countries have increased pollution by heavy metals, which is a concern for human health and the environment. In this study, 230 surface soil samples (0-20cm) were collected from agricultural areas of Jiaxing, a rapidly industrializing area in the Yangtze Delta of China. Sequential Gaussian simulation (SGS) and multivariate factorial kriging analysis (FKA) were used to identify and explore the sources of heavy metal pollution for eight metals (Cu, Zn, Pb, Cr, Ni, Cd, Hg and As). Localized hot-spots of pollution were identified for Cu, Zn, Pb, Cr, Ni and Cd with area percentages of 0.48 percent, 0.58 percent, 2.84 percent, 2.41 percent, 0.74 percent, and 0.68 percent, respectively. The areas with Hg pollution covered approximately 38 percent whereas no potential pollution risk was found for As. The soil parent material and point sources of pollution had significant influences on Cr, Ni, Cu, Zn and Cd levels, except for the influence of agricultural management practices also accounted for micro-scale variations (nugget effect) for Cu and Zn pollution. Short-range (4km) diffusion processes had a significant influence on Cu levels, although they did not appear to be the dominant sources of Zn and Cd variation. The short-range diffusion pollution arising from current and historic industrial emissions and urbanization, and long-range (33km) variations in soil parent materials and/or diffusion jointly determined the current concentrations of soil Pb. The sources of Hg pollution risk may be attributed to the atmosphere deposition of industrial emission and historical use of Hg-containing pesticides. Copyright © 2014 Elsevier Inc. All rights reserved.

Investigation of Biogenic and Non-biogenic Methane Sources in Texas

NASA Astrophysics Data System (ADS)

Yang, S.; Talbot, R. W.; Liu, L.; Lan, X.

2016-12-01

Methane (CH4) is a potent greenhouse gas with its mixing ratio increasing in the global atmosphere. Texas is one of the significant areas where underestimation of CH4 emissions by the U.S. inventories are pronounced. This study focused on two areas of Texas: Houston, the energy capital of the world, and the Barnett Shale area which is one of the largest onshore natural gas fields in the United States. The investigation of background CH4 and the fingerprints of CH4 emissions are critical to understanding potential impacts of extensive nature gas operations in these two areas. One-year of stationary CH4 measurements were studied to deduce the regional background CH4 characteristics and to identify the principle CH4 sources in Houston. Key information concerning CH4 sources can be obtained through the stable carbon isotope δ13CH4 during two field campaigns using a state-of-the-art mobile laboratory. CH4 mixing ratio and δ13C in CH4 were sampled by two cavity ring-down spectrometers (CRDS), one of which is coupled to a custom air core 13C sampling device which can supply more than 600 measurements for each plume analysis. Here, we report results of the overall δ13CH4 values and CH4 emission signatures derived from thirty-three sources in the two studied areas, ranging from oil production and processing, waste managements and landfills, to livestock. δ13CH4 signatures of these sources vary from -76‰ to -23‰. Several repeated measurements were sampled to investigate the variability of source signatures. We investigated a case of unexpected massive CH4 leaking detected near the San Jacinto River Fleet site. At the regional scale, the comparison of background δ13CH4 signatures were conducted to obtain the difference of dominate CH4 sources in two study areas. At the local scale, the combination of tower and mobile lab measurements were used to estimate and characterize CH4 emissions in Houston. The results and findings can supply valuable references for the local emission inventory and atmospheric model inputs.

Special Analysis for the Disposal of the Lawrence Livermore National Laboratory Low Activity Beta/Gamma Sources Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shott, Gregory J.

This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) Low Activity Beta/Gamma Sources waste stream (BCLALADOEOSRP, Revision 0) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL Low Activity Beta/Gamma Sources waste stream consists of sealed sources that are no longer needed. The LLNL Low Activity Beta/Gamma Sources waste stream required a special analysis because cobalt-60 (60Co), strontium-90 (90Sr), cesium-137 (137Cs), and radium-226 (226Ra) exceeded the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclearmore » Security Administration Nevada Field Office [NNSA/NFO] 2015). The results indicate that all performance objectives can be met with disposal of the LLNL Low Activity Beta/Gamma Sources in a SLB trench. The LLNL Low Activity Beta/Gamma Sources waste stream is suitable for disposal by SLB at the Area 5 RWMS. However, the activity concentration of 226Ra listed on the waste profile sheet significantly exceeds the action level. Approval of the waste profile sheet could potentially allow the disposal of high activity 226Ra sources. To ensure that the generator does not include large 226Ra sources in this waste stream without additional evaluation, a control is need on the maximum 226Ra inventory. A limit based on the generator’s estimate of the total 226Ra inventory is recommended. The waste stream is recommended for approval with the control that the total 226Ra inventory disposed shall not exceed 5.5E10 Bq (1.5 Ci).« less

Occurrence and carcinogenic potential of airborne polycyclic aromatic hydrocarbons in some large-scale enclosed/semi-enclosed vehicle parking areas.

PubMed

Li, Huiru; Zeng, Xiangying; Zhang, Delin; Chen, Pei; Yu, Zhiqiang; Sheng, Guoying; Fu, Jiamo; Peng, Ping'an

2014-06-15

Polycyclic aromatic hydrocarbons (PAHs) originating from vehicle exhaust have aroused much attention due to their potential healthy effect. In this study, air samples were collected from three representative parking lots in a metropolitan area, analyzed for PAHs and evaluated for inhalation risk. Atmospheric PAH levels of these parking areas ranged between 1,178-4,793 ng m(-3), one order of magnitude higher than general urban areas. Their benzo[a]pyrene equivalent (BaPeq) values varied in 11.0-98.0 ng m(-3), far exceeding the air quality standard of WHO (1.0 ng m(-3)). Monte Carlo simulation (100,000 trials) results suggest that the potential lifetime inhalation cancer risks of PAHs were 0.27 × 10(-5) to 7.11 × 10(-5) for park employees, which are in the acceptable range acknowledged by US EPA (1.0 × 10(-6) to 1.0 × 10(-4)). Several source diagnostic methods proved that vehicle exhaust was the dominant PAH contributor of these parks with the contribution percentages being >53%; oil combustion and/or coal combustion were other important sources. Logarithms of gas-particle distribution coefficients (Kps) of PAHs in all studied parks were linearly correlated with those of both their sub-cooled vapor pressures (pLs) and octanol-air partition coefficients (KOAs). The correlation coefficients indicated that both adsorption onto black carbon and absorption into organic matter were involved in the partition process, but the latter was dominant. Copyright © 2014 Elsevier B.V. All rights reserved.

Contamination, Transport, and Exposure Mapping and Assessment of Karst Groundwater Systems in Northern Puerto Rico Using GIS

NASA Astrophysics Data System (ADS)

Howard, J.; Schifman, L. A.; Irrizary, C.; Torres, P.; Padilla, I. Y.

2011-12-01

Ground waters from karst aquifer systems are one of the most important sources of freshwater worldwide and are highly vulnerable to both natural and anthropogenic contamination. Contaminants released into karst groundwater systems move through complex pathways from their sources to discharge areas of potential exposure. Points of exposure can include wells, springs, and surface waters that serve as drinking water sources. In Puerto Rico, the North Coast Limestone Aquifer System, which extends 90 miles across the north coast with an area of nearly 700 sq. miles, provides more than 50% of the potable water demand for industrial and drinking purposes. Historical reports from the 1980s revealed that volatile organic compounds, phthalates, and metals were close to or exceeded maximum contaminant levels. Exposure to such contaminants has been reported to cause reproductive and developmental issues, such as preterm birth. Since there is minimal understanding of the extent of contamination it is important to identify areas of potential concern. Preliminary analysis of 20 groundwater/springs and 20 tap water sites within the North Coast suggest that contamination is still a major concern. In addition, mixed effects models analyses suggest that >60% of pre-term birth rates may be explained by the presence of sites contaminated with volatile organic compounds, phthalates, and metals within the North Coast region. This presentation will focus primarily on how GIS was used as a tool for developing sampling strategies for collecting groundwater and tap water sources within the North Coast Limestone Aquifer System of Puerto Rico. In addition, the linkage of contamination, transport, and exposure to volatile organic compounds and phthalates will be addressed.

Fluoride in the environment and its metabolism in humans.

PubMed

Jha, Sunil Kumar; Mishra, Vinay Kumar; Sharma, Dinesh Kumar; Damodaran, Thukkaram

2011-01-01

The presence of environmental fluoride and its impact on human health is well documented. When consumed in adequate quantity, fluoride prevents dental caries, assists in the formation of dental enamels, and prevents deficiencies in bone mineralization. At excessive exposure levels, ingestion of fluoride causes dental fluorosis skeletal fluorosis, and manifestations such as gastrointestinal, neurological, and urinary problems. The distribution of fluoride in the environment is uneven and largely is believed to derive from geogenic causes. The natural sources of fluoride are fluorite, fluorapatite, and cryolite, whereas anthropogenic sources include coal burning, oil refining, steel production, brick-making industries, and phosphatic fertilizer plants, among others. Among the various sources of fluoride in the environment, those of anthropogenic origin have occasionally been considered to be major ones. The gourndwater is more susceptible to fluoride accumulation and contamination than are other environmental media, primarily because of its contact with geological substrates underneath. The high fluoride concentration in water usually reflects the solubility of fluoride (CaF₂). High concentrations are also often associated with soft, alkaline, and calcium-deficient waters. The fluoride compounds that occur naturally in drinking water are almost totally bioavailable (90%) and are completely absorbed from the gastrointestinal tract. As a result, drinking water is considered to be the potential source of fluoride that causes fluorosis. Because the bioavailability of fluoride is generally reduced in humans when consumed with milk or a calcium-rich diet, it is highly recommended that the inhabitants of fluoride-contaminated areas should incorporate calcium-rich foods in their routine diet. Guidelines for limiting the fluoride intake from drinking water have been postulated by various authorities. Such limits are designed to protect public health and should reflect all fluoride intake sources, including dietary fluoride. The toxicological risks posed by fluoride could be better understood if epidemiological surveillance for dental and skeletal fluorosis would be systematically conducted in fluoride-affected areas. Such input would greatly improve understanding of the human dose-response relationship. Such surveillance of potentially high fluoride areas is also important because it would help to delineate, much earlier, the remedial measures that are appropriate for those areas.

Lisburne Group (Mississippian and Pennsylvanian), potential major hydrocarbon objective of Arctic Slope, Alaska

USGS Publications Warehouse

Bird, Kenneth J.; Jordan, Clifton F.

1977-01-01

The Lisburne Group, a thick carbonate-rock unit of Mississippian and Pennsylvanian age, is one of the most widespread potential reservoir-rock units in northern Alaska. A comprehensive review of the Lisburne in the subsurface of the eastern Arctic Slope indicates attractive reservoir characteristics in a favorable source and migration setting where numerous trapping mechanisms appear to be available. Evaluation of this group as a potential exploration objective is particularly timely because of impending offshore sales in the Beaufort Sea and current exploration programs under way in the Prudhoe Bay area and the Naval Petroleum Reserve. Dolomite and sandstone have been identified as reservoir rocks. Oolitic grainstone is a common rock type, but observations indicate little reservoir potential owing to complete void filling by calcite cement. The most important reservoir rock as judged by thickness, areal extent, and predictability is microsucrosic (10 to 30µ) dolomite of intertidal to supratidal origin. It is present throughout the Lisburne and is most abundant near the middle of the sequence. Northward it decreases in thickness from 1,000 ft (300 m) to less than 100 ft (30 m). Porosity of the dolomite as determined in selected wells averages between 10 and 15% and attains a maximum of slightly more than 25%. Net thickness of reservoir rocks (i.e., rocks with greater than 5% porosity) ranges in these wells from 40 to 390 ft (40 to 120 m). Oil shows are common, and drill-stem tests have yielded as much as 1,600 bbl/day of oil and 22 MMcf/day of gas in the Lisburne pool of the Prudhoe Bay field and as much as 2,057 bbl/day of salt water outside the field area. The occurrence of dolomite over such a large area makes its presence in the offshore Beaufort Sea and adjacent Naval Petroleum Reserve 4 fairly certain. The presence of sandstone as thick as 140 ft (40 m) in the middle and upper part of the Lisburne in two coastal wells suggests that larger areas of sandstone may be found on the north in offshore areas. Shows of oil and gas and a saltwater flow of 1,470 bbl/day have been recorded from this sandstone facies. Shales of Permian and Cretaceous ages unconformably overlie the Lisburne, providing adequate sealing beds above potential reservoirs. Impermeable limestone (completely cemented grainstone) and thin beds of shale may serve as seals within the Lisburne, but the possibility of fractures in these units may negate their sealing capability. The most favorable source rock for Lisburne hydrocarbons appears to be Cretaceous shale that unconformably overlies the Lisburne east of Prudhoe Bay. This shale is reported to be a rich source rock and is the most likely source for the entire Prudhoe Bay field. A source within the Lisburne or within the underlying Kayak Shale is postulated for oil shows in the southernmost Lisburne wells. This postulated source may be in a more basinal facies of the Lisburne and may be similar to dark shale in the upper Lisburne in thrust slices to dark shale in the upper Lisburne in thrust slices in the Brooks Range. Coal in the underlying Endicott Group is a possible source for dry gas. At present, much of this coal probably is in a gas-generating regime downdip from the Prudhoe Bay field. Stratigraphic traps involving the Lisburne Group may have resulted from widespread Permian and Cretaceous unconformities. Structural traps related to normal faulting may be present along the trend of the Barrow arch, and faulted anticlines are numerous in the foothills of the Brooks Range. Combination traps are possible along the trend of the Barrow arch.

Potential soil carbon sequestration in overgrazed grassland ecosystems

NASA Astrophysics Data System (ADS)

Conant, Richard T.; Paustian, Keith

2002-12-01

Excessive grazing pressure is detrimental to plant productivity and may lead to declines in soil organic matter. Soil organic matter is an important source of plant nutrients and can enhance soil aggregation, limit soil erosion, and can also increase cation exchange and water holding capacities, and is, therefore, a key regulator of grassland ecosystem processes. Changes in grassland management which reverse the process of declining productivity can potentially lead to increased soil C. Thus, rehabilitation of areas degraded by overgrazing can potentially sequester atmospheric C. We compiled data from the literature to evaluate the influence of grazing intensity on soil C. Based on data contained within these studies, we ascertained a positive linear relationship between potential C sequestration and mean annual precipitation which we extrapolated to estimate global C sequestration potential with rehabilitation of overgrazed grassland. The GLASOD and IGBP DISCover data sets were integrated to generate a map of overgrazed grassland area for each of four severity classes on each continent. Our regression model predicted losses of soil C with decreased grazing intensity in drier areas (precipitation less than 333 mm yr-1), but substantial sequestration in wetter areas. Most (93%) C sequestration potential occurred in areas with MAP less than 1800 mm. Universal rehabilitation of overgrazed grasslands can sequester approximately 45 Tg C yr-1, most of which can be achieved simply by cessation of overgrazing and implementation of moderate grazing intensity. Institutional level investments by governments may be required to sequester additional C.

Self-Heating Effects In Polysilicon Source Gated Transistors

PubMed Central

Sporea, R. A.; Burridge, T.; Silva, S. R. P.

2015-01-01

Source-gated transistors (SGTs) are thin-film devices which rely on a potential barrier at the source to achieve high gain, tolerance to fabrication variability, and low series voltage drop, relevant to a multitude of energy-efficient, large-area, cost effective applications. The current through the reverse-biased source barrier has a potentially high positive temperature coefficient, which may lead to undesirable thermal runaway effects and even device failure through self-heating. Using numerical simulations we show that, even in highly thermally-confined scenarios and at high current levels, self-heating is insufficient to compromise device integrity. Performance is minimally affected through a modest increase in output conductance, which may limit the maximum attainable gain. Measurements on polysilicon devices confirm the simulated results, with even smaller penalties in performance, largely due to improved heat dissipation through metal contacts. We conclude that SGTs can be reliably used for high gain, power efficient analog and digital circuits without significant performance impact due to self-heating. This further demonstrates the robustness of SGTs. PMID:26351099

Where did Roman masons get their material from? A preliminary DRIFTS/PCA investigation on mortar aggregates from X Regio buildings in the Veneto area (NE Italy) and their potential sources.

PubMed

De Lorenzi Pezzolo, Alessandra; Colombi, Michela; Mazzocchin, Gian Antonio

2018-05-22

In this work, preliminary results are presented of an ongoing investigation aiming to identify the possible material sources employed by ancient Romans in their building activity in the X Regio, the European region corresponding to present north-eastern Italy and Istria (Croatia and Slovenia). The 63-420 μm fraction of the aggregate component recovered from eleven mortar fragments of buildings located in the Veneto area (in or close to Lio Piccolo, Vicenza, and Padua) is studied by diffuse reflection infrared Fourier transform spectroscopy and compared through principal component analysis to samples collected from local potential sources of raw materials. In this regard, the investigated samples from Lio Piccolo present a distinctive complexity, being this site located within the Venice lagoon, an area that has since been undergoing dramatic changes both due to natural and anthropic causes. The Vicenza and Padua sites were considered for comparison sake because they are or were located close to two rivers, the Bacchiglione and the Brenta, that in ancient times flowed into the Venice lagoon. As expected, from the exploratory investigation reported here, no firm conclusions can be obtained for the mortar samples collected in Lio Piccolo, whereas the likely provenance of the aggregate component of the samples from Vicenza and Padova from the Bacchiglione and the Brenta riverbeds, respectively, is confirmed.

A GIS technology based potential eco-risk assessment of metals in urban soils in Beijing, China.

PubMed

Wang, Meie; Bai, Yanying; Chen, Weiping; Markert, Bernd; Peng, Chi; Ouyang, Zhiyun

2012-02-01

Ecological risks of heavy metals in urban soils were evaluated using Beijing, China as an example. Cadmium, Cu, Zn, Pb, Cr and Ni contents of 233 surface soils sampled by 1 min latitude × 1 min longitude grid were used to identify their spatial distribution patterns and potential emission sources. Throughout the city, longer the duration of urbanization greater was the accumulations of heavy metals especially, Cd, Cu, Pb, and Zn. The soil Zn mainly came from the wears of vehicular tires. Point source emissions of heavy metals were few and far in the downwind south-east quadrant of Beijing. The calculated risk indices showed potential median eco-risks in the ancient central city. No potential high eco-risk due to soil-borne heavy metals was found. The potential medium eco-risk areas in Beijing would expand from the initial 24 to 110 km(2) if soil pH were to reduce by 0.5 units in anticipation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Improved quantification of CO2 emission at Campi Flegrei by combined Lagrangian Stochastic and Eulerian dispersion modelling

NASA Astrophysics Data System (ADS)

Pedone, Maria; Granieri, Domenico; Moretti, Roberto; Fedele, Alessandro; Troise, Claudia; Somma, Renato; De Natale, Giuseppe

2017-12-01

This study investigates fumarolic CO2 emissions at Campi Flegrei (Southern Italy) and their dispersion in the lowest atmospheric boundary layer. We innovatively utilize a Lagrangian Stochastic dispersion model (WindTrax) combined with an Eulerian model (DISGAS) to diagnose the dispersion of diluted gas plumes over large and complex topographic domains. New measurements of CO2 concentrations acquired in February and October 2014 in the area of Pisciarelli and Solfatara, the two major fumarolic fields of Campi Flegrei caldera, and simultaneous measurements of meteorological parameters are used to: 1) test the ability of WindTrax to calculate the fumarolic CO2 flux from the investigated sources, and 2) perform predictive numerical simulations to resolve the mutual interference between the CO2 emissions of the two adjacent areas. This novel approach allows us to a) better quantify the CO2 emission of the fumarolic source, b) discriminate ;true; CO2 contributions for each source, and c) understand the potential impact of the composite CO2 plume (Pisciarelli ;plus; Solfatara) on the highly populated areas inside the Campi Flegrei caldera.

EFFECT OF NITROGEN SOURCE ON THE GROWTH AND TOXICITY OF THREE POTENTIALLY HARMFUL DINOFLAGELLATES

EPA Science Inventory

Increases in population and agriculture in coastal areas can result in increased nutrient inputs and alterations in the ratios of organic to inorganic nutrients in coastal waters. Such changes in coastal nutrient regimes can affect phytoplankton community structure by creating c...

Petroleum source potential of the Lower Cretaceous mudstone succession of the NPRA and Colville Delta area, North Slope Alaska, based on sonic and resistivity logs

USGS Publications Warehouse

Keller, Margaret A.; Bird, Kenneth J.

2003-01-01

Resource assessment of the North Slope of Alaska by the U. S. Geological Survey includes evaluation of the petroleum source potential of Mesozoic and Cenozoic rocks using the delta log R technique (Passey and others, 1990). Porosity and resistivity logs are used in combination with thermal maturity data to produce a continuous profile of total organic carbon content in weight % (TOC). From the pattern and amount of TOC in the profile produced, the depositional setting and thus the petroleum source-rock potential (kerogen type) of the organic matter can be inferred and compared to interpretations from other data such as Rock-Eval pyrolysis. TOC profiles determined by this technique for the contiguous interval of pebble shale unit, Hue Shale (including the Gamma Ray Zone or GRZ), and lower part of the Torok Formation indicate important potential for petroleum generation in the Tunalik 1, Inigok 1, N. Inigok 1, Kuyanak 1, Texaco Colville Delta 1, Nechelik 1, and Bergschrund 1 wells of the western North Slope region. TOC profiles suggest that this interval contains both type II and III kerogens – consistent with proposed depositional models -- and is predominantly greater than 2 wt. % TOC (cut-off used for effective source potential). Average TOC for the total effective section of the pebble shale unit + Hue Shale ranges from 2.6 to 4.1 wt % TOC (values predominantly 2-8% TOC) over 192-352 ft. Source potential for the lower Torok Formation, which also has interbedded sandstone and lean mudstone, is good to negligible in these 7 wells.

Comparison of Physics Frameworks for WebGL-Based Game Engine

NASA Astrophysics Data System (ADS)

Yogya, Resa; Kosala, Raymond

2014-03-01

Recently, a new technology called WebGL shows a lot of potentials for developing games. However since this technology is still new, there are still many potentials in the game development area that are not explored yet. This paper tries to uncover the potential of integrating physics frameworks with WebGL technology in a game engine for developing 2D or 3D games. Specifically we integrated three open source physics frameworks: Bullet, Cannon, and JigLib into a WebGL-based game engine. Using experiment, we assessed these frameworks in terms of their correctness or accuracy, performance, completeness and compatibility. The results show that it is possible to integrate open source physics frameworks into a WebGLbased game engine, and Bullet is the best physics framework to be integrated into the WebGL-based game engine.

Dipole source localization of event-related brain activity indicative of an early visual selective attention deficit in ADHD children.

PubMed

Jonkman, L M; Kenemans, J L; Kemner, C; Verbaten, M N; van Engeland, H

2004-07-01

This study was aimed at investigating whether attention-deficit hyperactivity disorder (ADHD) children suffer from specific early selective attention deficits in the visual modality with the aid of event-related brain potentials (ERPs). Furthermore, brain source localization was applied to identify brain areas underlying possible deficits in selective visual processing in ADHD children. A two-channel visual color selection task was administered to 18 ADHD and 18 control subjects in the age range of 7-13 years and ERP activity was derived from 30 electrodes. ADHD children exhibited lower perceptual sensitivity scores resulting in poorer target selection. The ERP data suggested an early selective-attention deficit as manifested in smaller frontal positive activity (frontal selection positivity; FSP) in ADHD children around 200 ms whereas later occipital and fronto-central negative activity (OSN and N2b; 200-400 ms latency) appeared to be unaffected. Source localization explained the FSP by posterior-medial equivalent dipoles in control subjects, which may reflect the contribution of numerous surrounding areas. ADHD children have problems with selective visual processing that might be caused by a specific early filtering deficit (absent FSP) occurring around 200 ms. The neural sources underlying these problems have to be further identified. Source localization also suggested abnormalities in the 200-400 ms time range, pertaining to the distribution of attention-modulated activity in lateral frontal areas.

3D thermal history and maturity modelling of the Levant Basin and Margin

NASA Astrophysics Data System (ADS)

Daher, Samer Bou; Ducros, Mathieu; Michel, Pauline; Nader, Fadi H.; Littke, Ralf

2015-04-01

The gas discoveries recorded in the Levant Basin in the last decade have redirected the industrial and academic communities' interest to this frontier basin and its surroundings. The reported gas in Miocene reservoirs has been assumed to be derived from biogenic sources, although little data has been published so far. The thickness of the sedimentary column and the presence of direct hydrocarbon indicators (DHI) observed in the seismic data suggest the presence of promising prospective thermogenic petroleum systems in deeper intervals in the Levant Basin and along its Margin. In this study we present a large scale 3D thermal history and maturity model of the Levant Basin and Margin, integrating all available calibration data, source rock information collected from onshore Lebanon, and published data. In the first part we will present the main input and assumptions that were made in terms of thicknesses, lithologies, and boundary conditions. In the second part we will discuss the analysed source rocks, their petroleum generation potential and their kinetics. In the third part we will present modelling results including depth maps for key isotherms in addition to transformation ratio and vitrinite reflectance maps for proven and speculative source rocks at different time steps. This will provide a comprehensive assessment of the potential thermogenic petroleum systems in the study area, and allow us to illustrate and discuss the differences between the basinal, marginal, and onshore part of the study area as well as the potential of the northern vis a vis the southern offshore Levant Basin. This model will also allow us to analyse the sensitivity of the system to the various poorly constrained parameters in frontier basins (e.g. crustal thickness, rifting phases, lithologies) and thus identify the most critical data to be collected for future exploration and de-risking strategies.

Geochemical evaluation of part of the Cambay basin, India

DOE Office of Scientific and Technical Information (OSTI.GOV)

Banerjee, A.; Rao, K.L.N.

1993-01-01

In Broach-Jambusar and Ahmedabad-Mehsana blocks of Cambay basin, India, the hydrocarbon generated (HCG) and hydrocarbon expelled (HCE) per unit area of four Paleogene formations were computed at 38 locations to select the best targets and thus reduce exploration risk. Fractional generation curves, which show relation between vitrinite reflectance and fraction of original generative potential converted to hydrocarbons, were constructed for study areas and used to calculate HCG through remaining generation potential (S[sub 2] of Rock-Eval) and the thickness of the sedimentary section. HCE was estimated by subtracting volatile hydrocarbon content (S[sub 1] of Rock-Eval), representing the unexpelled in-situ-generated bitumen, frommore » the computed value of HCG. HCG and HCE, which combine source rock richness, thickness, and maturity, are useful for comparative evaluation of charging capacity of source rocks. Positive and negative HCEs characterize drainage and accumulation locales, respectively. In the study areas, the major generative depressions are at Sobhasan/Linch/Wadu and Ahmedabad in the Ahmedabad-Mehsana block and the Tankari and Broach depressions in the Broach-Jambusar block. In these areas, Paleogene source rocks have generated between 3 million and 12 million MT hydrocarbon/km[sup 2]. The major known oil and gas accumulations, which are in middle to lower Eocene sandstones in vicinity of the generative depressions, overlie 2 million to 7 million MT hydrocarbon/km[sup 2] and HCG contours in both blocks and correlate well with negative HCE in the reservoir. Isopach maps of several major middle to lower Eocene reservoir sandstones in conjunction with HCG maps for Paleogene section help to delineate favorable exploration locales. 23 refs., 31 figs.« less

Quantifying sediment source contributions in coastal catchments impacted by the Fukushima nuclear accident with carbon and nitrogen elemental concentrations and stable isotope ratios

NASA Astrophysics Data System (ADS)

Laceby, J. Patrick; Huon Huon, Sylvain; Onda, Yuichi; Evrard, Olivier

2016-04-01

The Fukushima Dai-ichi Nuclear Power Plant accidental release of radioactive contaminants resulted in the significant fallout of radiocesium over several coastal catchments in the Fukushima Prefecture. Radiocesium, considered to be the greatest risk to the short and long term health of the local community, is rapidly bound to fine soil particles and thus is mobilized and transported during soil erosion and runoff processes. As there has been a broad-scale decontamination of rice paddy fields and rural residential areas in the contaminated region, one important long term question is whether there is, or may be, a downstream transfer of radiocesium from forests that covered over 65% of the most contaminated region. Accordingly, carbon and nitrogen elemental concentrations and stable isotope ratios are used to determine the relative contributions of forests and rice paddies to transported sediment in three contaminated coastal catchments. Samples were taken from the three main identified sources: cultivated soils (rice paddies and fields, n=30), forest soils (n=45), and subsoils (channel bank and decontaminated soils, n = 25). Lag deposit sediment samples were obtained from five sampling campaigns that targeted the main hydrological events from October 2011 to October 2014. In total, 86 samples of deposited sediment were analyzed for particulate organic matter elemental concentrations and isotope ratios, 24 from the Mano catchment, 44 from the Niida catchment, and 18 from the Ota catchment. Mann-Whitney U-tests were used to examine the source discrimination potential of this tracing suite and select the appropriate tracers for modelling. The discriminant tracers were modelled with a concentration-dependent distribution mixing model. Preliminary results indicate that cultivated sources (predominantly rice paddies) contribute disproportionately more sediment per unit area than forested regions in these contaminated catchments. Future research will examine if there are areas in particular where forest sources have elevated concentrations and may require some attention in the decontamination and monitoring of potential radiocesium downstream transfers.

Impact of methodological "shortcuts" in conducting public health surveys: Results from a vaccination coverage survey

PubMed Central

Luman, Elizabeth T; Sablan, Mariana; Stokley, Shannon; McCauley, Mary M; Shaw, Kate M

2008-01-01

Background Lack of methodological rigor can cause survey error, leading to biased results and suboptimal public health response. This study focused on the potential impact of 3 methodological "shortcuts" pertaining to field surveys: relying on a single source for critical data, failing to repeatedly visit households to improve response rates, and excluding remote areas. Methods In a vaccination coverage survey of young children conducted in the Commonwealth of the Northern Mariana Islands in July 2005, 3 sources of vaccination information were used, multiple follow-up visits were made, and all inhabited areas were included in the sampling frame. Results are calculated with and without these strategies. Results Most children had at least 2 sources of data; vaccination coverage estimated from any single source was substantially lower than from all sources combined. Eligibility was ascertained for 79% of households after the initial visit and for 94% of households after follow-up visits; vaccination coverage rates were similar with and without follow-up. Coverage among children on remote islands differed substantially from that of their counterparts on the main island indicating a programmatic need for locality-specific information; excluding remote islands from the survey would have had little effect on overall estimates due to small populations and divergent results. Conclusion Strategies to reduce sources of survey error should be maximized in public health surveys. The impact of the 3 strategies illustrated here will vary depending on the primary outcomes of interest and local situations. Survey limitations such as potential for error should be well-documented, and the likely direction and magnitude of bias should be considered. PMID:18371195

Risk assessment for the reintroduction of anadromous salmonids upstream of Chief Joseph and Grand Coulee Dams, Northeastern Washington

USGS Publications Warehouse

Hardiman, Jill M.; Breyta, Rachel B.; Haskell, Craig A.; Ostberg, Carl O.; Hatten, James R.; Connolly, Patrick J.

2017-09-12

The Upper Columbia United Tribes (UCUT; Spokane, Colville, Kootenai, Coeur d’Alene, and Kalispel Tribes) and Washington Department of Fish and Wildlife want to reintroduce anadromous salmonids to their historical range to restore ecosystem function and lost cultural and spiritual relationships in the upper Columbia River, northeastern Washington. The UCUT contracted with the U.S. Geological Survey to assess risks to resident taxa (existing fish populations in the reintroduction area upstream of Chief Joseph and Grand Coulee Dams) and reintroduced salmon associated with reintroduction. We developed a risk assessment framework for reintroduction of anadromous salmonids upstream of Chief Joseph and Grand Coulee Dams. To accomplish this goal, we applied strategies identified in previous risk assessment frameworks for reintroduction. The risk assessment is an initial step towards an anadromous reintroduction strategy. An initial list of potential donor sources for reintroduction species was developed from previous published sources for Chinook Salmon (Oncorhynchus tshawytscha) donors in the Transboundary Reach of the Columbia River, British Columbia; an ecological risk assessment of upper Columbia River hatchery programs on non-target taxa of concern; and a review of existing hatchery programsDuring two workshops, we further identified and ranked potential donor sources of anadromous Redband Trout (steelhead; O. mykiss), Chinook Salmon, Sockeye Salmon (O. nerka), and Coho Salmon (O. kisutch). We also identified resident fish populations of interest and their primary habitat, location, status, and pathogen concerns to determine the potential risks of reintroduction. Species were deemed of interest based on resource management and potential interactions (that is, genetics, competition, and predation) with introduced species. We developed tables of potential donors by species and characterized potential sources (hatchery and natural origins), populations (individual runs), broodstock management and history, and potential constraints (that is, Endangered Species Act [ESA] listing, Evolutionarily Significant Unit concerns, pathogens, and availability). During the workshops, a group of regional fisheries and topic experts subjectively ranked the relative risks of pathogens, genetic effects, predation, and competition to resident fish and reintroduced salmonids. We assessed the pathogen risk of each potential donor for introducing new pathogens and the increased burden to existing pathogens for resident species upstream of the dams. We considered genetic risks to resident and downstream conspecifics and ecological impacts, including competition for food and space, predator-prey interactions, and ecosystem benefits/impacts. Each reintroduced species donor source was ranked based on abundance/viability (demographic risk to source and feasibility of collection), ancestral/genetic similarity (evolutionary similarity to historical populations), local adaptation (geographic proximity/similarity of source conditions to reintroduction conditions), and life history compatibility (including migration; spawn timing; and relative usage of reservoir, main-stem, or tributary habitats) with environmental conditions in the reintroduction area. We synthesized this information by species for all potential donors, in which an overall score and ranking system was established for decision support in donor selection for reintroduction into the upper Columbia River. We also provided information outside the ranking process by:Identifying predator-prey interactions and competition for food and space among species,Developing a decision support framework for donor selection, andProviding decision support for reintroduction strategies.

Bandwidth Study on Energy Use and Potential Energy Saving Opportunities in U.S. Pulp and Paper Manufacturing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sabine Brueske, Caroline Kramer, Aaron Fisher

2015-06-01

Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. pulp and paper manufacturing. The study relies on multiple sources to estimate the energy used in six individual process areas, representing 52% of sector-wide energy consumption. Energy savings opportunities for individual processes are based on technologies currently in use or under development; the potential savings are then extrapolated to estimate sector-wide energy savings opportunity

Bandwidth Study on Energy Use and Potential Energy Savings Opportunities in U.S. Petroleum Refining

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sabine Brueske, Caroline Kramer, Aaron Fisher

2015-06-01

Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. petroleum refining. The study relies on multiple sources to estimate the energy used in nine individual process areas, representing 68% of sector-wide energy consumption. Energy savings opportunities for individual processes are based on technologies currently in use or under development; these potential savings are then extrapolated to estimate sector-wide energy savings opportunity.

Assessment of organochlorine pesticides residues in higher plants from oil exploration areas of Niger Delta, Nigeria.

PubMed

Sojinu, O Samuel; Sonibare, Oluwadayo O; Ekundayo, Olusegun O; Zeng, Eddy Y

2012-09-01

The concentrations and distributions of organochlorine pesticides (OCPs) in some higher plant samples collected from oil exploration areas of the Niger Delta, Nigeria were examined. The concentrations of Σ(25)OCP ranged from 82 to 424, 44 to 200 , 34 to 358, 33 to 106 and 16 to 75 ng/g in Olomoro, Oginni, Uzere, Irri and Calabar plants, respectively. The compositional profiles of the analysed OCPs in most of the plants showed no fresh inputs in the area. The OCPs detected in the samples could have resulted from pesticide usage for intense farming activities cum the use of pesticides to control household pests and insects in the area. Drilling fluids and corrosion inhibitors used in petroleum explorations also have chlorinated compounds as additives thereby serving as potential sources of OCPs. Among the studied plants, elephant grass showed high bioaccumulation and phytoremediation potentials of OCPs. The ΣHCH concentrations exceeded the allowable daily intake limit thereby serving as potential threat to humans. Copyright © 2012 Elsevier B.V. All rights reserved.

Corrective Action Investigation Plan for Corrective Action Unit 528: Polychlorinated Biphenyls Contamination, Nevada Test Site, Nevada, Rev. 0

DOE Office of Scientific and Technical Information (OSTI.GOV)

U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office

This Corrective Action Investigation Plan contains the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office's approach to collect the data necessary to evaluate corrective action alternatives appropriate for the closure of Corrective Action Unit (CAU) 528, Polychlorinated Biphenyls Contamination (PCBs), Nevada Test Site (NTS), Nevada, under the Federal Facility Agreement and Consent Order. Located in the southwestern portion of Area 25 on the NTS in Jackass Flats (adjacent to Test Cell C [TCC]), CAU 528 consists of Corrective Action Site 25-27-03, Polychlorinated Biphenyls Surface Contamination. Test Cell C was built to support the Nuclear Rocket Development Stationmore » (operational between 1959 and 1973) activities including conducting ground tests and static firings of nuclear engine reactors. Although CAU 528 was not considered as a direct potential source of PCBs and petroleum contamination, two potential sources of contamination have nevertheless been identified from an unknown source in concentrations that could potentially pose an unacceptable risk to human health and/or the environment. This CAU's close proximity to TCC prompted Shaw to collect surface soil samples, which have indicated the presence of PCBs extending throughout the area to the north, east, south, and even to the edge of the western boundary. Based on this information, more extensive field investigation activities are being planned, the results of which are to be used to support a defensible evaluation of corrective action alternatives in the corrective action decision document.« less

Cortical sources of visual evoked potentials during consciousness of executive processes.

PubMed

Babiloni, Claudio; Vecchio, Fabrizio; Iacoboni, Marco; Buffo, Paola; Eusebi, Fabrizio; Rossini, Paolo Maria

2009-03-01

What is the timing of cortical activation related to consciousness of visuo-spatial executive functions? Electroencephalographic data (128 channels) were recorded in 13 adults. Cue stimulus briefly appeared on right or left (equal probability) monitor side for a period, inducing about 50% of recognitions. It was then masked and followed (2 s) by a central visual go stimulus. Left (right) mouse button had to be clicked after right (left) cue stimulus. This "inverted" response indexed executive processes. Afterward, subjects said "seen" if they had detected the cue stimulus or "not seen" when it was missed. Sources of event-related potentials (ERPs) were estimated by LORETA software. The inverted responses were about 95% in seen trials and about 60% in not seen trials. Cue stimulus evoked frontal-parietooccipital potentials, having the same peak latencies in the seen and not seen data. Maximal difference in amplitude of the seen and not seen ERPs was detected at about +300-ms post-stimulus (P3). P3 sources were higher in amplitude in the seen than not seen trials in dorsolateral prefrontal, premotor and parietooccipital areas. This was true in dorsolateral prefrontal and premotor cortex even when percentage of the inverted responses and reaction time were paired in the seen and not seen trials. These results suggest that, in normal subjects, the primary consciousness enhances the efficacy of visuo-spatial executive processes and is sub-served by a late (100- to 400-ms post-stimulus) enhancement of the neural synchronization in frontal areas.

Pollution of the sediments of the coastal zone of the Sambia Peninsula and the Curonian Spit (Southeastern Baltic Sea).

PubMed

Krek, Alexander; Krechik, Viktor; Danchenkov, Aleksandr; Krek, Elena

2018-01-01

The detailed environmental survey of the coastal zone of the Kaliningrad Region northern coast was carried out. The pollutants distribution in the silty clay fraction and calculation of ecological indexes allowed the evaluation of distribution of potentially harmful elements (PHEs). The sources of pollution in the most intensively used areas were identified, and transit and accumulation zones were allocated. A large area of anomalous content of PHEs was revealed on the underwater coastal slope of the Curonian Spit National Park, which is situated far from the sources of pollution. The alongshore bed load transport provides the contamination of the underwater slope whereas the beaches are less exposed to pollution.

NASA Goddard Space Flight Center, on Behalf of the Fermi Large Area Telescope Collaboration

NASA Technical Reports Server (NTRS)

Thompson, David J.

2010-01-01

Because high-energy gamma rays can be produced by processes that also produce neutrinos, the gamma-ray survey of the sky by the Fermi (Gamma-ray Space Telescope offers a view of potential targets for neutrino observations. Gamma-ray bursts. Active Galactic Nuclei, and supernova remnants are all sites where hadronic, neutrino-producing interactions are plausible. Pulsars, pulsar wind nebulae, and binary sources are all phenomena that reveal leptonic particle acceleration through their gamma-ray emission. While important to gamma-ray astrophysics, such sources are of less interest to neutrino studies. This talk will present a broad overview of the constantly changing sky seen with the Large Area Telescope (LAT)on the Fermi spacecraft.

Utilization of Indonesia's Hot Spring Sources for Electricity using Kalina Cycle and Organic Rankine Cycle

NASA Astrophysics Data System (ADS)

Prabumukti, Grano; Purwanto; Widodo, Wahyu

2018-02-01

Indonesia posses 40% of the world's geothermal energy sources. The existence of hydrothermal sources is usually characterized by their surface manifestations such as hot springs, geysers and fumarole. Hot spring has a potential to be used as a heat source to generate electricity especially in a rural and isolated area. Hot springs can be converted into electricity by binary thermodynamic cycles such as Kalina cycle and ORC. The aim of this study is to obtain the best performances of cycle configuration and the potential power capacity. Simulation is conducted using UNISIM software with working fluid and its operating condition as the decision variables. The simulation result shows that R1234yf and propene with simple ORC as desired working fluid and cycle configuration. It reaches a maximum thermal efficiency up to 9.6% with a specific turbine inlet pressure. Higher temperature heat source will result a higher thermal efficiency‥ Cycle thermal efficiency varies from 4.7% to 9.6% depends on source of hot spring temperature. Power capacity that can be generated using Indonesia's hot spring is ranged from 2 kWe to 61.2 kWe. The highest capacity located in Kawah Sirung and the least located in Kaendi.

Sensitivity Studies of 3D Reservoir Simulation at the I-Lan Geothermal Area in Taiwan Using TOUGH2

NASA Astrophysics Data System (ADS)

Kuo, C. W.; Song, S. R.

2014-12-01

A large scale geothermal project conducted by National Science Council is initiated recently in I-Lan south area, northeastern Taiwan. The goal of this national project is to generate at least 5 MW electricity from geothermal energy. To achieve this goal, an integrated team which consists of various specialties are held together to investigate I-Lan area comprehensively. For example, I-Lan geological data, petrophysical analysis, seismicity, temperature distribution, hydrology, geochemistry, heat source study etc. were performed to build a large scale 3D conceptual model of the geothermal potential sites. In addition, not only a well of 3000m deep but also several shallow wells are currently drilling to give us accurate information about the deep underground. According to the current conceptual model, the target area is bounded by two main faults, Jiaosi and Choshui faults. The geothermal gradient measured at one drilling well (1200m) is about 49.1˚C/km. The geothermal reservoir is expected to occur at a fractured geological formation, Siling sandstone layer. The preliminary results of this area from all the investigations are used as input parameters to create a realistic numerical reservoir model. This work is using numerical simulator TOUGH2/EOS1 to study the geothermal energy potential in I-Lan area. Once we can successfully predict the geothermal energy potential in this area and generate 5 MW electricity, we can apply the similar methodology to the other potential sites in Taiwan, and therefore increase the percentage of renewable energy in the generation of electricity. A large scale of three-dimensional subsurface geological model is built mainly based on the seismic exploration of the subsurface structure and well log data. The dimensions of the reservoir model in x, y, and z coordinates are 20x10x5 km, respectively. Once the conceptual model and the well locations are set up appropriately based on the field data, sensitivity studies on production and injection rates, heat source, fractures, and all the relevant parameters are performed to evaluate their effects on temperature distribution of reservoir for 30 years. Through these sensitivity studies, we can design the better geothermal system in I-Lan area and reduce the risk of exploitation.

Evaluation of hydrologic conditions and nitrate concentrations in the Rio Nigua de Salinas alluvial fan aquifer, Salinas, Puerto Rico, 2002-03

USGS Publications Warehouse

Rodriguez, Jose M.

2006-01-01

A ground-water quality study to define the potential sources and concentration of nitrate in the Rio Nigua de Salinas alluvial fan aquifer was conducted between January 2002 and March 2003. The study area covers about 3,600 hectares of the coastal plain within the municipality of Salinas in southern Puerto Rico, extending from the foothills to the Caribbean Sea. Agriculture is the principal land use and includes cultivation of diverse crops, turf grass, bioengineered crops for seed production, and commercial poultry farms. Ground-water withdrawal in the alluvial fan was estimated to be about 43,500 cubic meters per day, of which 49 percent was withdrawn for agriculture, 42 percent for public supply, and 9 percent for industrial use. Ground-water flow in the study area was primarily to the south and toward a cone of depression within the south-central part of the alluvial fan. The presence of that cone of depression and a smaller one located in the northeastern quadrant of the study area may contribute to the increase in nitrate concentration within a total area of about 545 hectares by 'recycling' ground water used for irrigation of cultivated lands. In an area that covers about 405 hectares near the center of the Salinas alluvial fan, nitrate concentrations increased from 0.9 to 6.7 milligrams per liter as nitrogen in 1986 to 8 to 12 milligrams per liter as nitrogen in 2002. Principal sources of nitrate in the study area are fertilizers (used in the cultivated farmlands) and poultry farm wastes. The highest nitrogen concentrations were found at poultry farms in the foothills area. In the area of disposed poultry farm wastes, nitrate concentrations in ground water ranged from 25 to 77 milligrams per liter as nitrogen. Analyses for the stable isotope ratios of nitrogen-15/nitrogen-14 in nitrate were used to distinguish the source of nitrate in the coastal plain alluvial fan aquifer. Potential nitrate loads from areas under cultivation were estimated for the principal crops in the area. The load estimates ranged from 18 kilograms per hectare per year as nitrogen for sorghum crops to 430 kilograms per hectare per year as nitrogen for turf-grass farms. Potential nitrate load from poultry farm wastes and from communities with septic tanks were estimated at about 580 and 47 kilograms per hectare per year as nitrogen, respectively. Results obtained from the analyses of the stable isotope ratios of nitrogen-15/nitrogen-14 in nitrate samples indicated that the high nitrate concentrations are from poultry wastes near the foothills, whereas artificial fertilizers were estimated to contribute between 39 to 97 percent of the total nitrate in the central part of the alluvial fan.

Evaluation of carbon fluxes and trends (2000-2008) in the Greater Platte River Basin: a sustainability study on the potential biofuel feedstock development

USGS Publications Warehouse

Gu, Yingxin; Wylie, Bruce K.; Zhang, Li; Gilmanov, Tagir G.

2012-01-01

This study evaluates the carbon fluxes and trends and examines the environmental sustainability (e.g., carbon budget, source or sink) of the potential biofuel feedstock sites identified in the Greater Platte River Basin (GPRB). A 9-year (2000–2008) time series of net ecosystem production (NEP), a measure of net carbon absorption or emission by ecosystems, was used to assess the historical trends and budgets of carbon flux for grasslands in the GPRB. The spatially averaged annual NEP (ANEP) for grassland areas that are possibly suitable for biofuel expansion (productive grasslands) was 71–169 g C m−2 year−1 during 2000–2008, indicating a carbon sink (more carbon is absorbed than released) in these areas. The spatially averaged ANEP for areas not suitable for biofuel feedstock development (less productive or degraded grasslands) was −47 to 69 g C m−2 year−1 during 2000–2008, showing a weak carbon source or a weak carbon sink (carbon emitted is nearly equal to carbon absorbed). The 9-year pre-harvest cumulative ANEP was 1166 g C m−2 for the suitable areas (a strong carbon sink) and 200 g C m−2 for the non-suitable areas (a weak carbon sink). Results demonstrate and confirm that our method of dynamic modeling of ecosystem performance can successfully identify areas desirable and sustainable for future biofuel feedstock development. This study provides useful information for land managers and decision makers to make optimal land use decisions regarding biofuel feedstock development and sustainability.

Potential effects of surface coal mining on the hydrology of the Greenleaf-Miller area, Ashland coal field, southeastern Montana

USGS Publications Warehouse

Levings, G.W.

1982-01-01

The Greenleaf-Miller area of the Ashland coal field contains reserves of Federal coal that have been identified for potential lease sale. A hydrologic study was conducted in the potential lease area in 1981 to describe the existing hydrologic system and to assess potential impacts of surface coal mining on local water resources. The hydrologic data collected from wells, test holes, and springs were used to identify aquifers in the alluvium (Pleistocene and Holocene age) and the Tongue River member of the Fort Union Formation (Paleocene age). Coal, clinker, and sandstone beds comprise the aquifers in the Tongue River Member. Most streams are ephemeral and flow only as a result of precipitation. The only perennial surface-water flow in the study area is along short reaches downstream from springs. A mine plan for the area is not available; thus, the location of mine cuts, direction and rate of the mine expansion, and duration of mining are unknown. The mining of the Sawyer and Knoblock coal beds in the Tonge River Member would effect ground-water flow in the area. Declines in the potentiometric surface would be caused by dewatering where the mine pits intersect the water table. Wells and springs would be removed in the mine area; however, deeper aquifers are available as replacement sources of water. The chemical quality of the ground water would change after moving through the spoils. The change would be an increase in the concentration of dissolved solids. (USGS)

An atlas of eleven selected aquifers in New York

USGS Publications Warehouse

Waller, Roger Milton; Finch, Anne J.

1982-01-01

Water from 11 aquifer systems in New York, excluding Long Island , is used by 2.8 million people. Ten are in areas hydraulically connected with the master stream and have a shallow water table, the 11th is a buried valley system on the Lake Ontario Plain. In all systems, till, lake silt and clay, and bedrock knobs are interspersed within sand and gravel. Confining conditions occur locally in all systems and are extensive in some. Each area is partly urbanized, contains industry, and has an extensive transportation network, all of which may be sources of contamination. Well yields for public and industrial supply are commonly several hundred gallons per minute. More than 90 maps depict surficial geology, soil-zone permeability, aquifer dimensions and potential, water levels, and land use; tables of ground-water use, population served, and a summary of contamination potential are also given. Major concern in all areas is the potential for contamination and, in a few areas, adequacy of supply. The areas described are Schenectady, Endicott-Johnson City, Ramapo and Mahwah Rivers, Irondequoit Creek, Jamestown, Elmira-Horseheads-Big Flats, Cortland, Homer-Preble, Sprout and Fishkill Creeks, Fulton, and south Fallsburg-Woodbourne. (USGS)

Who provided maize to Chaco Canyon after the mid-12th-century drought?

USGS Publications Warehouse

Benson, Larry V.

2010-01-01

Between A.D. 1181 and 1200, in the early part of a climatically wet period, corn was imported to Chaco Canyon from a region outside the Chaco Halo (defined in this paper as the region between the base of the Chuska Mountains and Raton Wells). Strontium-isotope (87Sr/86Sr) analyses of 12 corn cobs dating to this period match 87Sr/86Sr ratios from five potential source areas, including: the Zuni region, the Mesa Verde-McElmo Dome area, the Totah, the Defiance Plateau, and Lobo Mesa. The latter two areas were eliminated from consideration as possible sources of corn in that they appear to have been unpopulated during the time period of interest. Therefore, it appears that the corn cobs were imported from the Zuni region, the Mesa Verde-McElmo Dome area, or the Totah area during a time when the climate was relatively wet and when a surplus of corn was produced in regions outside Chaco Canyon. Based on proximity to and cultural affiliation with Chaco Canyon, it is hypothesized that the corn probably was imported from the Totah.

Investigating the impact of local urban sources on total atmospheric mercury wet deposition in Cleveland, Ohio, USA

EPA Science Inventory

Event-based precipitation samples were collected at a downtown industrial and a predominantly upwind rural location in the Cleveland, Ohio metropolitan area from July 2009 through December 2010 to investigate the potential local total mercury (Hg) wet deposition enhancement in a ...

Ambient ammonia and related amines in and around a mink production facility

USDA-ARS?s Scientific Manuscript database

In areas where ammonia is a significant air pollutant or nuisance concern, knowledge of all potential source locations and strengths is paramount. The USEPA’s 2014 National Emissions Inventory estimates that nearly 80% of the national ammonia emissions are attributable to the agricultural sector an...

MERCURY CONCENTRATIONS IN SEDIMENT, WATER AND BIOTA COLLECTED FROM NEAR-COASTAL AREAS IMPACTED BY COMMON ESTUARINE STRESSORS

EPA Science Inventory

Mercury concentrations in non-commercial organisms indigenous to the Gulf of Mexico are not well characterized particularly when compared to potential sources. In response to this need, mercury levels were determined in sediment, water and various biota in reference and non-refer...

ENVIRONMENTAL EFFECTS OF A GOLF COMPLEX ON COASTAL WETLANDS IN THE GULF OF MEXICO

EPA Science Inventory

The increasing density of golf courses represents a potential source of contamination to nearby coastal wetlands and other near-shore areas. The chemical and biological magnitude of the problem is almost unknown. To provide perspective on this issue, the effects of golf complex r...

38 CFR 200.4 - Implementation of NEPA and related authorities.

Code of Federal Regulations, 2013 CFR

2013-07-01

... action reveals that air emissions exceed de minimis levels or otherwise that a formal Clean Air Act... RETIREMENT HOME COMPLIANCE WITH THE NATIONAL ENVIRONMENTAL POLICY ACT § 200.4 Implementation of NEPA and... aquifers (potential sources of drinking water); National Wildlife Refuges; National Parks; areas of...

Security Management Strategies for Protecting Your Library's Network.

ERIC Educational Resources Information Center

Ives, David J.

1996-01-01

Presents security procedures for protecting a library's computer system from potential threats by patrons or personnel, and describes how security can be breached. A sidebar identifies four areas of concern in security management: the hardware, the operating system, the network, and the user interface. A selected bibliography of sources on…

44 CFR 201.4 - Standard State Mitigation Plans.

Code of Federal Regulations, 2010 CFR

2010-10-01

... resources to reducing the effects of natural hazards. (b) Planning process. An effective planning process is... mitigation as well as to development in hazard-prone areas; a discussion of State funding capabilities for... identified. (iv) Identification of current and potential sources of Federal, State, local, or private funding...

44 CFR 201.4 - Standard State Mitigation Plans.

Code of Federal Regulations, 2013 CFR

2013-10-01

... resources to reducing the effects of natural hazards. (b) Planning process. An effective planning process is... mitigation as well as to development in hazard-prone areas; a discussion of State funding capabilities for... identified. (iv) Identification of current and potential sources of Federal, State, local, or private funding...

Distribution of Gull Specific Molecular Marker in Coastal Areas of Lake Ontario

EPA Science Inventory

Gulls have been implicated as primary sources of fecal contamination in the Great Lakes, a fact that may have health implications due to the potential spread of microbial pathogens by waterfowl. To better understand the spatial variability of gull fecal contamination, a gull-spe...

VOLATILE ORGANIC COMPOUND EMISSIONS FROM LATEX PAINT - PART 1. CHAMBER EXPERIMENTS AND SOURCE MODEL DEVELOPMENT

EPA Science Inventory

Latex paints are widely used in residential and commercial indoor environments. The surface areas covered by the paints in these environments are relatively large. Thus, latex paints have the potential for having a major impact on indoor air quality (IAQ). A study was undertaken ...

Impact of Mining Waste on Airborne Respirable Particulates in Northeastern Oklahoma, United States

EPA Science Inventory

Atmospheric dispersion of particles from mine waste is potentially an important route of human exposure to metals in communities close to active and abandoned mining areas. In this study, we assessed sources of mass and metal concentrations in two size fractions of respirable pa...

Evidence of sulfate-dependent anaerobic methane oxidation within an area impacted by coalbed methane-related gas migration

EPA Science Inventory

The rapid development of unconventional gas resources has been accompanied by an increase in public awareness regarding the potential effects of drilling operations on drinking water sources. Incidents have been reported involving blowouts (e.g., Converse County, WY; Lawrence Tow...

DOE Office of Scientific and Technical Information (OSTI.GOV)

BENNETT,D.B.; PAQUETTE,D.E.; KLAUS,K.

The BNL water supply system meets all water quality standards and has sufficient pumping and storage capacity to meet current and anticipated future operational demands. Because BNL's water supply is drawn from the shallow Upper Glacial aquifer, BNL's source water is susceptible to contamination. The quality of the water supply is being protected through (1) a comprehensive program of engineered and operational controls of existing aquifer contamination and potential sources of new contamination, (2) groundwater monitoring, and (3) potable water treatment. The BNL Source Water Assessment found that the source water for BNL's Western Well Field (comprised of Supply Wellsmore » 4, 6, and 7) has relatively few threats of contamination and identified potential sources are already being carefully managed. The source water for BNL's Eastern Well Field (comprised of Supply Wells 10, 11, and 12) has a moderate number of threats to water quality, primarily from several existing volatile organic compound and tritium plumes. The g-2 Tritium Plume and portions of the Operable Unit III VOC plume fall within the delineated source water area for the Eastern Well Field. In addition, portions of the much slower migrating strontium-90 plumes associated with the Brookhaven Graphite Research Reactor, Waste Concentration Facility and Building 650 lie within the Eastern source water area. However, the rate of travel in the aquifer for strontium-90 is about one-twentieth of that for tritium and volatile organic compounds. The Laboratory has been carefully monitoring plume migration, and has made adjustments to water supply operations. Although a number of BNL's water supply wells were impacted by VOC contamination in the late 1980s, recent routine analysis of water samples from BNL's supply wells indicate that no drinking water standards have been reached or exceeded. The high quality of the water supply strongly indicates that the operational and engineered controls implemented over the past ten years have effectively protected the quality of the water supply.« less

Petroleum hydrocarbons in a water-sediment system from Yellow River estuary and adjacent coastal area, China: Distribution pattern, risk assessment and sources.

PubMed

Wang, Min; Wang, Chuanyuan; Li, Yuanwei

2017-09-15

Aliphatic hydrocarbons (AHs), biomarker and polycyclic aromatic hydrocarbons (PAHs) concentrations of surface water and sediment samples collected from Yellow River Estuary and adjacent coastal area in China were measured to determine their spatial distributions, analyze their sources and evaluate the ecological risk of PAHs in the water-sediment system. The spatial distributions of n-alkane in sediments are mainly controlled by the mixing inputs of terrigenous and marine components. In comparison with AHs, the total concentrations of Σ16PAHs in surface sediments from a transect of the offshore area were noticeably higher than that of the riverine and estuary areas. Additionally, the AHs and total PAHs concentrations all indicated an overall pattern of a seaward decrease. The PAHs concentrations during the dry season (mainly in the form of dissolved phase) were higher than that of PAHs (mainly dissolved phase and particulate phase form) in the flooding season. In comparison with global concentration levels of PAHs, the level of PAHs in suspended particulate matter and sediments from the Yellow River Estuary was lower than those from other countries, while the concentration of PAHs in the dissolved phase were in the middle range. Petroleum contamination, mainly from oil exploration and discharge of pollutants from rivers, was the main source of n-alkanes. The PAHs in the river were mostly of petrogenic origin, while those in the estuarial and marine areas originated mainly from pyrogenic sources. The results of the toxicology assessment suggested that the PAHs in sediments from Yellow River Estuary and adjacent coastal area exhibited a low potential eco-toxicological contamination level. Copyright © 2017 Elsevier Ltd. All rights reserved.

Applications of stochastic models and geostatistical analyses to study sources and spatial patterns of soil heavy metals in a metalliferous industrial district of China.

PubMed

Zhong, Buqing; Liang, Tao; Wang, Lingqing; Li, Kexin

2014-08-15

An extensive soil survey was conducted to study pollution sources and delineate contamination of heavy metals in one of the metalliferous industrial bases, in the karst areas of southwest China. A total of 597 topsoil samples were collected and the concentrations of five heavy metals, namely Cd, As (metalloid), Pb, Hg and Cr were analyzed. Stochastic models including a conditional inference tree (CIT) and a finite mixture distribution model (FMDM) were applied to identify the sources and partition the contribution from natural and anthropogenic sources for heavy metal in topsoils of the study area. Regression trees for Cd, As, Pb and Hg were proved to depend mostly on indicators of anthropogenic activities such as industrial type and distance from urban area, while the regression tree for Cr was found to be mainly influenced by the geogenic characteristics. The FMDM analysis showed that the geometric means of modeled background values for Cd, As, Pb, Hg and Cr were close to their background values previously reported in the study area, while the contamination of Cd and Hg were widespread in the study area, imposing potentially detrimental effects on organisms through the food chain. Finally, the probabilities of single and multiple heavy metals exceeding the threshold values derived from the FMDM were estimated using indicator kriging (IK) and multivariate indicator kriging (MVIK). The high probabilities exceeding the thresholds of heavy metals were associated with metalliferous production and atmospheric deposition of heavy metals transported from the urban and industrial areas. Geostatistics coupled with stochastic models provide an effective way to delineate multiple heavy metal pollution to facilitate improved environmental management. Copyright © 2014 Elsevier B.V. All rights reserved.

Summary of hydrologic conditions of the Louisville area of Kentucky

USGS Publications Warehouse

Bell, Edwin Allen

1966-01-01

Water problems and their solutions have been associated with the growth and development of the Louisville area for more than a century. Many hydrologic data that aided water users in the past can be applied to present water problems and will be helpful for solving many similar problems in the future. Most of the water problems of Louisville, a water-rich area, concern management and are associated with the distribution of supplies, the quality of water, drainage, and waste disposal. The local hydrologic system at Louisville is dominated by the Ohio River and the glacial-outwash deposits beneath its flood plain. The water-bearing limestones in the uplands are ,secondary sources of water. The average flow of the Ohio River at Louisville, 73 billion gallons per day, and the potential availability of 370 million gallons per day of ground water suitable for industrial cooling purposes minimize the chance of acute water shortage in the area. Under current development, use of water averages about 211 million gallons per day, excluding about 392 million gallons of Ohio River water circulated daily through steampower plants and returned directly to the river. Optimum use and control of the water resources will be dependent on solving several water problems. The principal sources of water are in the Ohio River bottom land, whereas the new and potential centers of use are in the uplands. Either water must be piped to these new centers from the present sources or new supplies must be developed. Available data on streamflow and ground water are adequate to plan for the development of small local supplies. Since the completion of floodwalls and levees in 1953, widespread damage from flooding is a thing of the past in the Louisville area. Some local flooding of unprotected areas and of lowlands along tributary streams still takes place. The analyses of streamflow data are useful in planning for protection of these areas, but additional streamflow records and flood-area mapping are needed to best solve the problem. Droughts are a problem only to users of small water supplies in the uplands, where additional water either can be imported or developed locally. Pollution and undesirable chemical quality of water for some uses are the most serious drawbacks to the optimum development of the water resources in Louisville and Jefferson County. Available chemical analyses of ground water are useful for determining its suitability for various uses, but additional data are needed to guide management decisions. Sources of contamination should be inventoried and water samples analyzed periodically to monitor changes in quality.

Potential use of ionic species for identifying source land-uses of stormwater runoff.

PubMed

Lee, Dong Hoon; Kim, Jin Hwi; Mendoza, Joseph A; Lee, Chang-Hee; Kang, Joo-Hyon

2017-02-01

Identifying critical land-uses or source areas is important to prioritize resources for cost-effective stormwater management. This study investigated the use of information on ionic composition as a fingerprint to identify the source land-use of stormwater runoff. We used 12 ionic species in stormwater runoff monitored for a total of 20 storm events at five sites with different land-use compositions during the 2012-2014 wet seasons. A stepwise forward discriminant function analysis (DFA) with the jack-knifed cross validation approach was used to select ionic species that better discriminate the land-use of its source. Of the 12 ionic species, 9 species (K + , Mg 2+ , Na + , NH 4 + , Br - , Cl - , F - , NO 2 - , and SO 4 2- ) were selected for better performance of the DFA. The DFA successfully differentiated stormwater samples from urban, rural, and construction sites using concentrations of the ionic species (70%, 95%, and 91% of correct classification, respectively). Over 80% of the new data cases were correctly classified by the trained DFA model. When applied to data cases from a mixed land-use catchment and downstream, the DFA model showed the greater impact of urban areas and rural areas respectively in the earlier and later parts of a storm event.

Detecting black bear source–sink dynamics using individual-based genetic graphs

PubMed Central

Draheim, Hope M.; Moore, Jennifer A.; Etter, Dwayne; Winterstein, Scott R.; Scribner, Kim T.

2016-01-01

Source–sink dynamics affects population connectivity, spatial genetic structure and population viability for many species. We introduce a novel approach that uses individual-based genetic graphs to identify source–sink areas within a continuously distributed population of black bears (Ursus americanus) in the northern lower peninsula (NLP) of Michigan, USA. Black bear harvest samples (n = 569, from 2002, 2006 and 2010) were genotyped at 12 microsatellite loci and locations were compared across years to identify areas of consistent occupancy over time. We compared graph metrics estimated for a genetic model with metrics from 10 ecological models to identify ecological factors that were associated with sources and sinks. We identified 62 source nodes, 16 of which represent important source areas (net flux > 0.7) and 79 sink nodes. Source strength was significantly correlated with bear local harvest density (a proxy for bear density) and habitat suitability. Additionally, resampling simulations showed our approach is robust to potential sampling bias from uneven sample dispersion. Findings demonstrate black bears in the NLP exhibit asymmetric gene flow, and individual-based genetic graphs can characterize source–sink dynamics in continuously distributed species in the absence of discrete habitat patches. Our findings warrant consideration of undetected source–sink dynamics and their implications on harvest management of game species. PMID:27440668

Can the source–sink hypothesis explain macrofaunal abundance patterns in the abyss? A modelling test

PubMed Central

Hardy, Sarah M.; Smith, Craig R.; Thurnherr, Andreas M.

2015-01-01

Low food availability is a major structuring force in deep-sea benthic communities, sustaining only very low densities of organisms in parts of the abyss. These low population densities may result in an Allee effect, whereby local reproductive success is inhibited, and populations are maintained by larval dispersal from bathyal slopes. This slope–abyss source–sink (SASS) hypothesis suggests that the abyssal seafloor constitutes a vast sink habitat with macrofaunal populations sustained only by an influx of larval ‘refugees' from source areas on continental slopes, where higher productivity sustains greater population densities. Abyssal macrofaunal population densities would thus be directly related to larval inputs from bathyal source populations. We evaluate three predictions derived from the SASS hypothesis: (i) slope-derived larvae can be passively transported to central abyssal regions within a single larval period, (ii) projected larval export from slopes to the abyss reproduces global patterns of macrofaunal abundance and (iii) macrofaunal abundance decreases with distance from the continental slope. We find that abyssal macrofaunal populations are unlikely to be sustained solely through influx of larvae from slope sources. Rather, local reproduction probably sustains macrofaunal populations in relatively high-productivity abyssal areas, which must also be considered as potential larval source areas for more food-poor abyssal regions. PMID:25948686

Identification and bioactive potential of marine microorganisms from selected Florida coastal areas.

PubMed

Christensen, Anna; Martin, Glenroy D A

2017-08-01

The ocean, with its rich untapped chemical biodiversity, continues to serve as a source of potentially new therapeutic agents. The evaluation of the diversity of cultivable microorganisms from the marine sponge Halichondria panicea and ocean sediment samples were examined and their potential as sources of antimicrobial and antiproliferative agents were investigated. The marine sponge and sediments were collected at different depths (0.9-6 meters) and locations in Florida, including Florida Keys, Port St. Joe in Pensacola, Pensacola Bay, Pensacola Beach, and Fort Pickens. Twenty-one cultivatable isolates were grouped according to their morphology and identified using 16S rRNA molecular taxonomy. The bacterial community identified consisted of members belonging to the Actinobacteria, Bacteroidetes, Proteobacteria (Alpha- and Gamma-classes) and Firmicutes phylogeny. Seven of the microbes exhibited mild to significant cytotoxic activities against five microbial indicators but no significant cytotoxic activities were observed against the pancreatic (PANC-1) nor the multidrug-resistant ovarian cancer cell lines (NCI/ADR). This work reaffirms the phyla Actinobacteria and Proteobacteria as sources of potential bioactive natural product candidates for drug discovery and development. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Marine Microorganism: An Underexplored Source of l-Asparaginase.

PubMed

Prihanto, A A; Wakayama, M

l-Asparaginase (EC 3.5.1.1) is an enzyme that catalyzes the hydrolysis of l-asparagine to l-aspartic acid. This enzyme has an important role in medicine and food. l-Asparaginase is a potential drug in cancer therapy. Furthermore, it is also applied for reducing acrylamide, a carcinogenic compound in baked and fried foods. Until now, approved l-asparaginases for both applications are few due to their lack of appropriate properties. As a result, researchers have been enthusiastically seeking new sources of enzyme with better performance. A great number of terrestrial l-asparaginase-producing microorganisms have been reported but unfortunately, almost all failed to meet criteria for cancer therapy and acrylamide reducing agent. As a largest area than Earth, marine environment, by contrast, has not been optimally explored yet. So far, a great challenge facing an exploration of marine microorganisms is mainly due to their harsh, mysterious, and dangerous environment. It is clear that marine environment, a gigantic potential source for marine natural products is scantily revealed, although several approaches and technologies have been developed. This chapter presents the historical of l-asparaginase discovery and applications. It is also discussed, how the marine environment, even though offering a great potency but is still one of the less explored area for l-asparaginase-producing microorganisms. © 2016 Elsevier Inc. All rights reserved.

Water resources of the Marquette Iron Range area, Michigan

USGS Publications Warehouse

Wiitala, Sulo Werner; Newport, Thomas Gwyn; Skinner, Earl L.

1967-01-01

Large quantities of water are needed in the beneficiation and pelletizing processes by which the ore mined from low-grade iron-formations is upgraded into an excellent raw material for the iron and steel industry. Extensive reserves of low-grade iron-formation available for development herald an intensification of the demands upon the area's water supplies. This study was designed to provide water facts for public and private agencies in planning orderly development and in guiding the management of the water resources to meet existing and new requirements. Inland lakes and streams are the best potential sources of water for immediate development. The natural flow available for 90 percent of the time in the Middle and East Branches of the Escanaba River, the Carp River, and the Michigamme River is about 190 cubic feet per second. Potential storage sites are identified, and their complete development could increase the available supply from the above streams to about 450 cubic feet per second. Outwash deposits are the best potential sources of ground water. Large supplies could be developed from extensive outwash deposits in the eastern part of the area adjacent to Goose Lake Outlet and the East Branch Escanaba River. Other areas of outwash occur in the vicinity of Humboldt, West Branch Creek, and along the stream valleys. Streamflow data were used to make rough approximations of the ground-water potential in some areas. In general, however, the available data were not sufficient to permit quantitative evaluation of the potential ground-water supplies. Chemical quality of the surface and ground waters of the area is generally acceptable for most uses. Suspended sediment in the form of mineral tailings in effluents from ore-processing plants is a potential problem. Existing plants use settling basins to effectively remove most of the suspended material. Available records indicate that suspended-sediment concentrations and loads in the receiving waters have not been significantly increased by these operations. Present water use is about 60 cubic feet per second in the area. Thus, available water supplies are believed to be adequate for existing and foreseeable new uses. Water management, rather than water availability, is of prime consideration in this area. Time distribution of available water supplies, distribution of water to points of use, effect of surface-water development upon ground water and vice versa, and possible conflicts with competing uses are some of the management problems that are discussed. The presence of many inland lakes, favorable storage sites on streams, and several promising acquifers provide flexibility in possible water-management operations. A discussion of the interrelationships between surface and ground water and a ground-water budget are presented to render a better understanding of the hydrologic system with which water management will be concerned.

Organic waste compounds as contaminants in Milwaukee-area streams

USGS Publications Warehouse

Baldwin, Austin K.; Corsi, Steven R.; Magruder, Christopher; Magruder, Matthew; Bruce, Jennifer L.

2015-09-22

Organic waste compounds (OWCs) are ingredients and by-products of common agricultural, industrial, and household substances that can contaminate our streams through sources like urban runoff, sewage overflows, and leaking septic systems. To better understand how OWCs are affecting Milwaukee-area streams, the U.S. Geological Survey, in cooperation with the Milwaukee Metropolitan Sewerage District, conducted a three-year study to investigate the presence and potential toxicity of 69 OWCs in base flow, stormflow, pore water, and sediment at 14 stream sites and 3 Milwaukee harbor locations. This fact sheet summarizes the major findings of this study, including detection frequencies and concentrations, potential toxicity, the prevalence of polycyclic aromatic hydrocarbons (PAHs), and the influence of urbanization.

[Localization of attention related cortical structures by evoked potentials].

PubMed

Szelenberger, W

2000-01-01

Attention is an ambiguous concept, difficult to direct implementation in neurophysiological studies. The paper presents application of the Continuous Attention Test (CAT) items as stimuli in event related potential (ERP) studies on attention. Stimuli with high demand of attention result in enlarged N1 component in occipital derivations. Spatial analysis revealed increased positivity in frontal derivations. Three-dimensional image of cortical current density by means of Low Resolution Electromagnetic Tomography (LORETA) revealed sources of N1 component in occipital, parietal and postero-temporal derivations with the maximal current value at 17 Brodmann area. After target stimuli increase of current density in frontal derivations was observed, with the maximal value in the left 9 Brodmann area.

An innovative expression model of human health risk based on the quantitative analysis of soil metals sources contribution in different spatial scales.

PubMed

Zhang, Yimei; Li, Shuai; Wang, Fei; Chen, Zhuang; Chen, Jie; Wang, Liqun

2018-09-01

Toxicity of heavy metals from industrialization poses critical concern, and analysis of sources associated with potential human health risks is of unique significance. Assessing human health risk of pollution sources (factored health risk) concurrently in the whole and the sub region can provide more instructive information to protect specific potential victims. In this research, we establish a new expression model of human health risk based on quantitative analysis of sources contribution in different spatial scales. The larger scale grids and their spatial codes are used to initially identify the level of pollution risk, the type of pollution source and the sensitive population at high risk. The smaller scale grids and their spatial codes are used to identify the contribution of various sources of pollution to each sub region (larger grid) and to assess the health risks posed by each source for each sub region. The results of case study show that, for children (sensitive populations, taking school and residential area as major region of activity), the major pollution source is from the abandoned lead-acid battery plant (ALP), traffic emission and agricultural activity. The new models and results of this research present effective spatial information and useful model for quantifying the hazards of source categories and human health a t complex industrial system in the future. Copyright © 2018 Elsevier Ltd. All rights reserved.

Geothermic Potential Assessment of hydrothermal vents of Township Barranca De Upia - Meta - Colombia

NASA Astrophysics Data System (ADS)

Chica, J.; Chicangana, G.; Eco Energy Research Group

2013-05-01

Hydrothermal vents have been traditionally exploited in Colombia as a source of tourism revenue such as pools and saunas. Leaving aside its high potential for geothermal power generation in applications like heating, drying, cooling, extensive use in crops, livestock, electricity generation and more. Currently the use given to this natural resource in the town of Barranca de Upia in Meta department, central Colombia, is like Wellness Centre. However, the geothermal gradient for the area where hydrothermal vents occur, indicates that the water emerges at temperatures above 70 ° C (Alfaro et al., 2003), which opens a window of opportunity to assess their geothermal potential, in order to know the actual energy potential of the region as an option of augmenting their development. this research is the analysis of information gathered from databases in gravimetry and magnetometry of the study area and the temperatures measured in wells derived from the oil industry. Based on that information, a numerical analysis of the data will be performed in order to establish a model to parameterize the energy potential of the study area and identify possible uses of the energy contained by the hydrothermal vents.

MOVES-Matrix and distributed computing for microscale line source dispersion analysis.

PubMed

Liu, Haobing; Xu, Xiaodan; Rodgers, Michael O; Xu, Yanzhi Ann; Guensler, Randall L

2017-07-01

MOVES and AERMOD are the U.S. Environmental Protection Agency's recommended models for use in project-level transportation conformity and hot-spot analysis. However, the structure and algorithms involved in running MOVES make analyses cumbersome and time-consuming. Likewise, the modeling setup process, including extensive data requirements and required input formats, in AERMOD lead to a high potential for analysis error in dispersion modeling. This study presents a distributed computing method for line source dispersion modeling that integrates MOVES-Matrix, a high-performance emission modeling tool, with the microscale dispersion models CALINE4 and AERMOD. MOVES-Matrix was prepared by iteratively running MOVES across all possible iterations of vehicle source-type, fuel, operating conditions, and environmental parameters to create a huge multi-dimensional emission rate lookup matrix. AERMOD and CALINE4 are connected with MOVES-Matrix in a distributed computing cluster using a series of Python scripts. This streamlined system built on MOVES-Matrix generates exactly the same emission rates and concentration results as using MOVES with AERMOD and CALINE4, but the approach is more than 200 times faster than using the MOVES graphical user interface. Because AERMOD requires detailed meteorological input, which is difficult to obtain, this study also recommends using CALINE4 as a screening tool for identifying the potential area that may exceed air quality standards before using AERMOD (and identifying areas that are exceedingly unlikely to exceed air quality standards). CALINE4 worst case method yields consistently higher concentration results than AERMOD for all comparisons in this paper, as expected given the nature of the meteorological data employed. The paper demonstrates a distributed computing method for line source dispersion modeling that integrates MOVES-Matrix with the CALINE4 and AERMOD. This streamlined system generates exactly the same emission rates and concentration results as traditional way to use MOVES with AERMOD and CALINE4, which are regulatory models approved by the U.S. EPA for conformity analysis, but the approach is more than 200 times faster than implementing the MOVES model. We highlighted the potentially significant benefit of using CALINE4 as screening tool for identifying potential area that may exceeds air quality standards before using AERMOD, which requires much more meteorology input than CALINE4.

Characterizing Salmonella Contamination in Two Rendering Processing Plants.

PubMed

Gong, Chao; Jiang, Xiuping

2017-02-01

A microbiological investigation on Salmonella contamination was conducted in two U.S. rendering plants to investigate the potential cross-contamination of Salmonella in the rendering processing environment. Sampling locations were predetermined at the areas where Salmonella contamination may potentially occur, including raw materials receiving, crax (rendered materials before grinding process) grinding, and finished meal loading-out areas. Salmonella was either enumerated directly on xylose lysine Tergitol 4 agar plates or enriched in Rappaport-Vassiliadis and tetrathionate broths. The presumptive Salmonella isolates were confirmed using CHROMagar plating and latex agglutination testing and then characterized using pulsed-field gel electrophoresis, serotyping, and biofilm-forming determination. Among 108 samples analyzed, 79 (73%) samples were Salmonella positive after enrichment. Selected Salmonella isolates (n = 65) were assigned to 31 unique pulsed-field gel electrophoresis patterns, with 16 Salmonella serotypes, including Typhimurium and Mbandaka, identified as predominant serotypes and 10 Salmonella strains determined as strong biofilm formers. Our results indicated that the raw materials receiving area was the primary source of Salmonella and that the surfaces surrounding crax grinding and finished meal loading-out areas harbor Salmonella in biofilms that may recontaminate the finished meals. The same Salmonella serotypes found in both raw materials receiving and the finished meal loading-out areas suggested a potential of cross-contamination between different areas in the rendering processing environment.

Strong motion simulation by the composite source modeling: A case study of 1679 M8.0 Sanhe-Pinggu earthquake

NASA Astrophysics Data System (ADS)

Liu, Bo-Yan; Shi, Bao-Ping; Zhang, Jian

2007-05-01

In this study, a composite source model has been used to calculate the realistic strong ground motions in Beijing area, caused by 1679 M S8.0 earthquake in Sanhe-Pinggu. The results could provide us the useful physical parameters for the future seismic hazard analysis in this area. Considering the regional geological/geophysical background, we simulated the scenario earthquake with an associated ground motions in the area ranging from 39.3°N to 41.1°N in latitude and from 115.35°E to 117.55°E in longitude. Some of the key factors which could influence the characteristics of strong ground motion have been discussed, and the resultant peak ground acceleration (PGA) distribution and the peak ground velocity (PGV) distribution around Beijing area also have been made as well. A comparison of the simulated result with the results derived from the attenuation relation has been made, and a sufficient discussion about the advantages and disadvantages of composite source model also has been given in this study. The numerical results, such as the PGA, PGV, peak ground displacement (PGD), and the three-component time-histories developed for Beijing area, have a potential application in earthquake engineering field and building code design, especially for the evaluation of critical constructions, government decision making and the seismic hazard assessment by financial/insurance companies.

Rockfall susceptibility mapping of Yosemite Valley (USA) using a high-resolution digital elevation model

NASA Astrophysics Data System (ADS)

Pannatier, A.; Oppikofer, T.; Jaboyedoff, M.; Stock, G. M.

2009-04-01

In Yosemite National Park (California, USA) rockfalls from the steep valley flanks are frequent (>600 documented events in 150 years) and threaten infrastructure in this popular tourist area. This study focuses on a methodology to map the susceptibility to rockfall initiation based on a high-resolution digital elevation model (HRDEM) obtained from aerial laser scanning (1 meter cell size). This methodology is based on geometric factors derived from the HRDEM, i.e., the steepness of the topography, the presence of joints or fractures enabling either a planar or a wedge failure mechanism, and a high denudation potential. The slope angle histogram computed using standard GIS routines was simulated using Gaussian distributions, which were attributed to different parts of the topography, i.e., the cliffs, the valley flanks and the valley floor. Slopes steeper than 36° are found to form cliffs and thus potentially lead to rockfalls. A morpho-structural analysis of the HRDEM was performed in Coltop3D software to determine the major discontinuity sets that shape the topography. Kinematic analyses were made for each of these 7 discontinuity sets in order to determine the HRDEM cells that fulfil the geometric criteria for a planar or wedge failure mechanism. Most of the cliffs in Yosemite Valley enable one or both of these failure mechanisms. The denudation potential was assessed using the sloping local base level (SLBL) concept. The SLBL defines a basal erosion surface and the above lying rock masses (up to 400 m in some of the vertical cliffs) are susceptible to erosion by mass wasting. A thickness of 20 m above the SLBL surface was chosen as lower limit for the denudation potential criterion. The HRDEM cells that satisfy 1, 2 or all 3 criteria are considered having low, moderate and high susceptibility to rockfall initiation. The areas with highest susceptibility (El Capitan, Glacier Point, Yosemite Falls and Half Dome) coincide well with post-glacial talus accumulations and historic rockfall sources. Compared to previous maps of potential rockfall sources that were mainly based on the slope angle criterion, this study provides a more refined analysis of potential rockfall sources and is useful for focussing detailed field investigations on those areas with high susceptibility.

Concentrations and Origins of Atmospheric Lead and Other Trace Species at a Rural Site in Northern China

NASA Technical Reports Server (NTRS)

Li, Can; Wen, Tianxue; Li, Zhanqing; Dickerson, Russell R.; Yang, Yongjie; Zhao, Yanan; Wang, Yuesi; Tsay, Si-Chee

2010-01-01

In this study we analyze the ambient levels of lead and other trace species in the bulk aerosol samples from a rural site approx.70 km ESE of Beijing in spring 2005. Lead (0.28+/-0.24 micro-g/cu m, average +/- standard deviation), along with several pollution \\related trace elements, was enriched by over 100 fold relative to the Earth's crust. The ambient lead levels showing large synoptic variations were well-correlated with other anthropogenic pollutants (e.g., CO and SO2). The Unmix receptor model resolved four factors in the aerosol composition data: a biomass burning source, an industrial and coal combustion source, a secondary aerosol source, and a dust source. The first three sources were strongest in weak southerly winds ahead of cold fronts, while the dust source peaked in strong northerly winds behind cold fronts. The second source, primarily representing emissions from industrial processes and relatively small \\scale coal burning such as in home and institutional heating, was identified as the main source of ambient lead in this study. Mobile sources might also contribute to this factor, but there was no distinct evidence of emissions due to combustion of leaded gasoline, despite a correlation between lead and CO. Potential source contribution function, calculated from backward trajectories and aerosol composition, further reveals that lead observed in this study was predominantly from the populated and industrialized areas to the south and SW of Xianghe, rather than Beijing to the west. Our results and several recent studies show that the lead levels in suburban areas near big cities in China, although generally lower than those in industrial districts and urban areas, are substantial (near or above 0.15 micro-g/cu m). More extensive studies on airborne lead and its emission sources in China are called for.

Estimation of diffuse and point source microbial pollution in the ribble catchment discharging to bathing waters in the north west of England.

PubMed

Wither, A; Greaves, J; Dunhill, I; Wyer, M; Stapleton, C; Kay, D; Humphrey, N; Watkins, J; Francis, C; McDonald, A; Crowther, J

2005-01-01

Achieving compliance with the mandatory standards of the 1976 Bathing Water Directive (76/160/EEC) is required at all U.K. identified bathing waters. In recent years, the Fylde coast has been an area of significant investments in 'point source' control, which have not proven, in isolation, to satisfactorily achieve compliance with the mandatory, let alone the guide, levels of water quality in the Directive. The potential impact of riverine sources of pollution was first confirmed after a study in 1997. The completion of sewerage system enhancements offered the potential for the study of faecal indicator delivery from upstream sources comprising both point sources and diffuse agricultural sources. A research project to define these elements commenced in 2001. Initially, a desk study reported here, estimated the principal infrastructure contributions within the Ribble catchment. A second phase of this investigation has involved acquisition of empirical water quality and hydrological data from the catchment during the 2002 bathing season. These data have been used further to calibrate the 'budgets' and 'delivery' modelling and these data are still being analysed. This paper reports the initial desk study approach to faecal indicator budget estimation using available data from the sewerage infrastructure and catchment sources of faecal indicators.

The cortical spatiotemporal correlate of otolith stimulation: Vestibular evoked potentials by body translations.

PubMed

Ertl, M; Moser, M; Boegle, R; Conrad, J; Zu Eulenburg, P; Dieterich, M

2017-07-15

The vestibular organ senses linear and rotational acceleration of the head during active and passive motion. These signals are necessary for bipedal locomotion, navigation, the coordination of eye and head movements in 3D space. The temporal dynamics of vestibular processing in cortical structures have hardly been studied in humans, let alone with natural stimulation. The aim was to investigate the cortical vestibular network related to natural otolith stimulation using a hexapod motion platform. We conducted two experiments, 1. to estimate the sources of the vestibular evoked potentials (VestEPs) by means of distributed source localization (n=49), and 2. to reveal modulations of the VestEPs through the underlying acceleration intensity (n=24). For both experiments subjects were accelerated along the main axis (left/right, up/down, fore/aft) while the EEG was recorded. We were able to identify five VestEPs (P1, N1, P2, N2, P3) with latencies between 38 and 461 ms as well as an evoked beta-band response peaking with a latency of 68 ms in all subjects and for all acceleration directions. Source localization gave the cingulate sulcus visual (CSv) area and the opercular-insular region as the main origin of the evoked potentials. No lateralization effects due to handedness could be observed. In the second experiment, area CSv was shown to be integral in the processing of acceleration intensities as sensed by the otolith organs, hinting at its potential role in ego-motion detection. These robust VestEPs could be used to investigate the mechanisms of inter-regional interaction in the natural context of vestibular processing and multisensory integration. Copyright © 2017 Elsevier Inc. All rights reserved.

Hydrogeologic and geochemical characterization of groundwater resources in Deep Creek Valley and adjacent areas, Juab and Tooele Counties, Utah, and Elko and White Pine Counties, Nevada

USGS Publications Warehouse

Gardner, Philip M.; Masbruch, Melissa D.

2015-09-18

Water-level altitude contours and groundwater ages indicate the potential for a long flow path from southwest to northeast between northern Spring and Deep Creek Valleys through Tippett Valley. Although information gathered during this study is insufficient to conclude whether or not groundwater travels along this interbasin flow path, dissolved sulfate and chloride data indicate that a small fraction of the lower altitude, northern Deep Creek Valley discharge may be sourced from these areas. Despite the uncertainty due to limited data collection points, a hydraulic connection between northern Spring Valley, Tippett Valley, and Deep Creek Valley appears likely, and potential regional effects resulting from future groundwater withdrawals in northern Spring Valley warrant ongoing monitoring of groundwater levels across this area.

Cuminum cyminum and Carum carvi: An update

PubMed Central

Johri, R. K.

2011-01-01

Cuminum cyminum and Carum carvi are the sources of cumin and caraway seeds respectively, which have been used since antiquity for the treatment of various indications in traditional healing systems in wide geographical areas. Cumin and caraway seeds are rich sources of essential oils and have been actively researched for their chemical composition and biological activities. In recent times (especially during the last 3 years) considerable progress has been made regarding validation of their acclaimed medicinal attributes by extensive experimental studies. In this attempt many novel bioactivities have been revealed. This review highlights the significance of cumin and caraway as potential source of diverse natural products and their medicinal applications. PMID:22096320

Crowdsourced Curriculum Development for Online Medical Education.

PubMed

Shappell, Eric; Chan, Teresa M; Thoma, Brent; Trueger, N Seth; Stuntz, Bob; Cooney, Robert; Ahn, James

2017-12-08

In recent years online educational content, efforts at quality appraisal, and integration of online material into institutional teaching initiatives have increased. However, medical education has yet to develop large-scale online learning centers. Crowd-sourced curriculum development may expedite the realization of this potential while providing opportunities for innovation and scholarship. This article describes the current landscape, best practices, and future directions for crowdsourced curriculum development using Kern's framework for curriculum development and the example topic of core content in emergency medicine. A scoping review of online educational content was performed by a panel of subject area experts for each step in Kern's framework. Best practices and recommendations for future development for each step were established by the same panel using a modified nominal group consensus process. The most prevalent curriculum design steps were (1) educational content and (2) needs assessments. Identified areas of potential innovation within these steps included targeting gaps in specific content areas and developing underrepresented instructional methods. Steps in curriculum development without significant representation included (1) articulation of goals and objectives and (2) tools for curricular evaluation. By leveraging the power of the community, crowd-sourced curriculum development offers a mechanism to diffuse the burden associated with creating comprehensive online learning centers. There is fertile ground for innovation and scholarship in each step along the continuum of curriculum development. Realization of this paradigm's full potential will require individual developers to strongly consider how their contributions will align with the work of others.

Crowdsourced Curriculum Development for Online Medical Education

PubMed Central

Chan, Teresa M; Thoma, Brent; Trueger, N Seth; Stuntz, Bob; Cooney, Robert; Ahn, James

2017-01-01

In recent years online educational content, efforts at quality appraisal, and integration of online material into institutional teaching initiatives have increased. However, medical education has yet to develop large-scale online learning centers. Crowd-sourced curriculum development may expedite the realization of this potential while providing opportunities for innovation and scholarship. This article describes the current landscape, best practices, and future directions for crowdsourced curriculum development using Kern’s framework for curriculum development and the example topic of core content in emergency medicine. A scoping review of online educational content was performed by a panel of subject area experts for each step in Kern’s framework. Best practices and recommendations for future development for each step were established by the same panel using a modified nominal group consensus process. The most prevalent curriculum design steps were (1) educational content and (2) needs assessments. Identified areas of potential innovation within these steps included targeting gaps in specific content areas and developing underrepresented instructional methods. Steps in curriculum development without significant representation included (1) articulation of goals and objectives and (2) tools for curricular evaluation. By leveraging the power of the community, crowd-sourced curriculum development offers a mechanism to diffuse the burden associated with creating comprehensive online learning centers. There is fertile ground for innovation and scholarship in each step along the continuum of curriculum development. Realization of this paradigm’s full potential will require individual developers to strongly consider how their contributions will align with the work of others. PMID:29464134

Evaluation of groundwater quality and selected hydrologic conditions in the South Coast aquifer, Santa Isabel area, Puerto Rico, 2008–09

USGS Publications Warehouse

Rodríguez, José M.

2013-01-01

The source of drinking water in the Santa Isabel and Coamo areas of Puerto Rico (Molina and Gómez-Gómez, 2008) is the South Coast aquifer (hereafter referred to as the aquifer), which supplies about 30,700 cubic meters per day (m³/d) to Puerto Rico Aqueduct and Sewer Authority (PRASA) public-supply wells. In addition, approximately 45 wells provide an estimated 33,700 m³/d of groundwater to irrigate crops in the area. In 1967, baseline nitrate concentrations in groundwater throughout most of the aquifer were generally less than 6 milligrams per liter (mg/L) as nitrogen in collected water samples (U.S. Geological Survey, 2012). In 2007, elevated nitrate concentrations were detected in the aquifer, near Santa Isabel and the foothills north of the coastal plain at Santa Isabel as part of a regional groundwater-quality assessment conducted by the U.S. Geological Survey (USGS) during 2007 (Rodríguez and Gómez-Gómez, 2008). The increase in nitrate concentrations has been of concern to local government agencies because of its potential effect on public supply. To address public-supply concerns, the USGS, in cooperation with the Puerto Rico Department of Natural and Environmental Resources (PRDNER), evaluated groundwater quality in the aquifer near the Santa Isabel area between January 2008 and May 2009. The objectives of the study were to (1) define the groundwater-quality conditions of the aquifer, with emphasis on the distribution of nitrate concentrations; (2) identify potential sources leading to elevated nitrate concentrations; (3) estimate the nitrate loads from major sources identified; and (4) estimate the groundwater withdrawals by principal-use categories in the area. Results of this study will be used by Commonwealth of Puerto Rico and Federal agencies in developing strategies that can result in containment of high nitrate groundwater to minimize degradation of fresh groundwater in the aquifer.

A study of photochemical againg of ambient air using Potential Aerosol Mass (PAM) chamber under the different sources and types of emissions

NASA Astrophysics Data System (ADS)

Lee, T.; Son, J.; Kim, J.; Kim, S.; Sung, K.; Park, G.; Link, M.; Park, T.; Kim, K.; Kang, S.; Ban, J.; Kim, D. S.

2016-12-01

Recent research proposed that Secondary Aerosol (SA) is important class of predicting future climate change scenarios, health effect, and a general air quality. However, there has been lack of studies to investigate SA formation all over the world. This study tried to focus on understanding potential secondary aerosol formation and its local impact by the photochemical aging of inorganic and organic aerosols in the ambient air using the Potential Aerosol Mass (PAM) chamber under the different sources and types of emissions. PAM chamber manufactured by Aerodyne make an oxidizing environment that simulates oxidation processes on timescales of 12-15 hrs in the atmosphere. Chemical compositions of ambient aerosol and aerosol that was aged in the PAM chamber were alternately measured every 2-minutes using the High Resolution-Time of Flight-Aerosol Mass Spectrometer (HR-ToF-AMS). HR-ToF-AMS provides non-refractory aerosol mass concentrations including nitrate, sulfate, hydrocarbon-like and oxygenated organic aerosol in real time. This study includes a residence area of mixture of sources, a forest site of dominant source of biogenic VOCs, an underground parking lot of dominant vehicle emission, and laboratory experiment of vehicle emissions under different fuels and speeds using the chassis dynamometer. As a result, it was revealed that gasoline and LPG vehicle relatively made more potential SA than diesel vehicle.

Physicochemical properties of fine aerosols at Plan d'Aups during ESCOMPTE

NASA Astrophysics Data System (ADS)

Marinoni, Angela; Laj, Paolo; Deveau, Pierre Alexandre; Marino, Federica; Ghermandi, Grazia; Aulagnier, Fabien; Cachier, Hélène

2005-03-01

The physical and chemical properties of aerosol particles were investigated at Plan d'Aups, one of the ESCOMPTE sites located in the St. Baume mountain area (700 m a.s.l.), 50 km east of Marseilles (France). The site is ideally located for assessing the vertical and horizontal extent of the pollution plume from the Marseilles-Berre area. Our study showed that polluted air masses from the Marseilles-Berre area are advected to Plan d'Aups in the early afternoon. Average daily concentration of particles reaches up to 40 μg m -3 while 1-h average particle number concentration is greater than 30,000 cm -3. Most of the particle mass is composed of SO 42- and organic carbon (OC). The chemical properties of the particles revealed that an additional source, possibly from the industrial area of Gardanne, contributes to the aerosol mass. This last source is characterised by significant emissions of elements, such as Zn, V, Al and Si. In addition to transport, we found that gas-to-particle conversion takes place at the interface between the free troposphere and the boundary layer. We estimated that on average, 30% of the particle number is accounted for by direct nucleation. This is potentially a major aerosol source to the free troposphere.

Urinary perchlorate exposure and risk in women of reproductive age in a fireworks production area of China.

PubMed

Li, Qin; Yu, Yun-jiang; Wang, Fei-fei; Chen, Shi-wu; Yin, Yan; Lin, Hai-peng; Che, Fei; Sun, Peng; Qin, Juan; Liu, Jie; Wang, Hong-mei

2014-07-01

Perchlorate is used widely in fireworks, and, if ingested, it has the potential to disrupt thyroid function. The concentrations of perchlorate in water and soil samples and in urine samples of women of reproductive age from Liuyang, the largest fireworks production area in China, were investigated. The results showed that the average perchlorate concentrations in groundwater, surface water, farmland soil, and urine samples of women from the fireworks production area were significantly greater than those from the control area. The health risk of perchlorate ingested through drinking water was assessed based on the mode recommended by the United States Environmental Protection Agency. The values of hazard quotient of river water and groundwater in the fireworks production area were much greater than the safe level (=1), which indicates that adverse health effects may result from perchlorate when these sources of water are used as drinking water. These results indicated that the environment of the fireworks production area has been polluted by perchlorate and that residents were and are facing greater exposure doses of perchlorate. Fireworks production enterprises may be a major source of perchlorate contamination.

Drugs and Cosmetics from the Sea

PubMed Central

Kijjoa, Anake; Sawangwong, Pichan

2004-01-01

The marine environment is a rich source of both biological and chemical diversity. This diversity has been the source of unique chemical compounds with the potential for industrial development as pharmaceuticals, cosmetics, nutritional supplements, molecular probes, fine chemicals and agrochemicals. In recent years, a significant number of novel metabolites with potent pharmacological properties has been discovered from the marine organisms. Although there are only a few marine-derived products currently on the market, several robust new compounds derived from marine natural products are now in the clinical pipeline, with more clinical development. While the marine world offers an extremely rich resource for novel compounds, it also represents a great challenge that requires inputs from various scientific areas to bring the marine chemical diversity up to its therapeutic potential.

Evaluation of hydrocarbon potential

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cashman, P.H.; Trexler, J.H. Jr.

1992-09-30

Task 8 is responsible for assessing the hydrocarbon potential of the Yucca Mountain vincinity. Our main focus is source rock stratigraphy in the NTS area in southern Nevada. (In addition, Trexler continues to work on a parallel study of source rock stratigraphy in the oil-producing region of east central Nevada, but this work is not funded by Task 8.) As a supplement to the stratigraphic studies, we are studying the geometry and kinematics of deformation at NTS, particularly as these pertain to reconstructing Paleozoic stratigraphy and to predicting the nature of the Late Paleozoic rocks under Yucca Mountain. Our stratigraphicmore » studies continue to support the interpretation that rocks mapped as the {open_quotes}Eleana Formation{close_quotes} are in fact parts of two different Mississippian units. We have made significant progress in determining the basin histories of both units. These place important constraints on regional paleogeographic and tectonic reconstructions. In addition to continued work on the Eleana, we plan to look at the overlying Tippipah Limestone. Preliminary TOC and maturation data indicate that this may be another potential source rock.« less

Analysis of field of view limited by a multi-line X-ray source and its improvement for grating interferometry.

PubMed

Du, Yang; Huang, Jianheng; Lin, Danying; Niu, Hanben

2012-08-01

X-ray phase-contrast imaging based on grating interferometry is a technique with the potential to provide absorption, differential phase contrast, and dark-field signals simultaneously. The multi-line X-ray source used recently in grating interferometry has the advantage of high-energy X-rays for imaging of thick samples for most clinical and industrial investigations. However, it has a drawback of limited field of view (FOV), because of the axial extension of the X-ray emission area. In this paper, we analyze the effects of axial extension of the multi-line X-ray source on the FOV and its improvement in terms of Fresnel diffraction theory. Computer simulation results show that the FOV limitation can be overcome by use of an alternative X-ray tube with a specially designed multi-step anode. The FOV of this newly designed X-ray source can be approximately four times larger than that of the multi-line X-ray source in the same emission area. This might be beneficial for the applications of X-ray phase contrast imaging in materials science, biology, medicine, and industry.

The relationship between historical development and potentially toxic element concentrations in urban soils.

PubMed

McIlwaine, Rebekka; Doherty, Rory; Cox, Siobhan F; Cave, Mark

2017-01-01

Increasing urbanisation has a direct impact on soil quality, resulting in elevated concentrations of potentially toxic elements (PTEs) in soils. This research aims to assess if soil PTE concentrations can be used as an 'urbanisation tracer' by investigating geogenic and anthropogenic source contributions and controls, and considering PTE enrichment across historical urban development zones. The UK cities of Belfast and Sheffield are chosen as study areas, where available shallow and deep concentrations of PTEs in soil are compared to identify geogenic and anthropogenic contributions to PTEs. Cluster analysis and principal component analysis are used to elucidate the main controls over PTE concentrations. Pollution indices indicate that different periods of historical development are linked to enrichment of different PTEs. Urban subdomains are identified and background values calculated using various methodologies and compared to generic site assessment criteria. Exceedances for a number of the PTEs considered suggest a potential human health risk could be posed across subdomains of both Belfast and Sheffield. This research suggests that airborne diffuse contamination from often historical sources such as traffic, domestic combustion and industrial processes contribute greatly to soil contamination within urban environments. The relationship between historical development and differing PTEs is a novel finding, suggesting that PTEs have the potential for use as 'urbanisation tracers'. The investigative methodology employed has potential applications for decision makers, urban planners, regulators and developers of urban areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

Investigating a cluster of Legionnaires' cases: public health implications.

PubMed

Carr, R; Warren, R; Towers, L; Bartholomew, A; Duggal, H V; Rehman, Y; Harrison, T G; Olowokure, B

2010-06-01

To describe the multidisciplinary investigation and management of a rapidly increasing number of cases of Legionnaires' disease in the North Shropshire area, UK during August 2006. Epidemiological and environmental investigation of a cluster of cases of Legionnaires' disease. Outbreak investigation included: agreeing case definitions; case finding; epidemiological survey; identification and environmental investigation of potential sources; microbiological analysis of clinical and environmental samples; mapping the location of potential sources; and the movement and residence of cases. Three cases of Legionnaires' disease were admitted to a local hospital between 30 and 31 August 2006. Two of these cases were Shropshire residents, with the third living in Wales. A fourth case was also identified which, it was thought, may have been linked to this cluster as the patient had a history of travel to the same area as the two Shropshire residents. Over the next few weeks, three more cases were identified, two of whom were admitted to hospital. Subsequent detailed environmental, epidemiological and microbiological investigation did not support the hypothesis that any of these cases could be linked to a common source. The results of this investigation strongly suggest that a single source was not responsible for the cluster, and it was concluded that this incident was a pseudo-outbreak. This investigation serves as a reminder that clusters can and do occur, and that an apparent outbreak may be a collection of sporadic cases distinguishable only by rigorous epidemiological, environmental and microbiological investigation. Copyright 2010. Published by Elsevier Ltd.

More wells will expand knowledge of Knox group, Black Warrior basin

USGS Publications Warehouse

Raymond, Dorothy E.

1991-01-01

The Cambrian-Ordovician Knox group of the Black Warrior basin in Alabama and Mississippi has attracted the interest of the oil industry because of recent significant discoveries of oil and gas in the age-equivalent Arbuckle group carbonates of the Arkoma, Ardmore, and Anadarko basins of Oklahoma. The geologic setting of these areas is described. Oil and gas potential is assessed and the Knox production history is given. Source rock potential is outlined.

The role of development of photovoltaics for Mongolia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Enebish, N.; Agchbayar, D.; Baatarkhuu, M.

1994-12-31

This paper describes an assessment of the potential applications of photovoltaic technology in Mongolia. Socio-economic conditions of the pastoral culture are described and it is shown that the photovoltaic system is the most suitable source of electricity and has potential for wide application. One application identified is for powering communications systems for herdspeople and other decentralized communities of Mongolian rural areas. Some strategies for the future development and application of photovoltaic systems in Mongolia are discussed.

Arsenic and heavy metals contamination, risk assessment and their source in drinking water of the Mardan District, Khyber Pakhtunkhwa, Pakistan.

PubMed

Gul, Nida; Shah, Mohammad Tahir; Khan, Sardar; Khattak, Nimat Ullah; Muhammad, Said

2015-12-01

The present study was conducted to investigate the physico-chemical characteristics in drinking water of Mardan District, Pakistan. Furthermore, water quality was evaluated for the risk assessment of arsenic and heavy metals (HMs) and their contamination sources. Representative groundwater samples of shallow and deep sources were collected in the study area. These samples were analyzed for physical parameters, anions, light metals (LMs) and HMs. Results were compared with the drinking water guideline values set by the World Health Organization and the US Environmental Protection Agency. Average concentrations of anions, LMs and HMs were found within the maximum allowable contaminant levels except for bicarbonates, Fe, Cu, and Pb. Results revealed that hazard quotients >1 were observed for shallow groundwater for 10% samples only, suggesting potential health risk from water consumption. Correlation analysis and principal component analysis showed a relationship among various physico-chemical parameters in both shallow and deep groundwater. Statistical analyses suggested the geogenic and anthropogenic sources for possible enhancement of various physico-chemical parameters in the aquifer system of the study area.

Microbiological quality of Puget Sound Basin streams and identification of contaminant sources

USGS Publications Warehouse

Embrey, S.S.

2001-01-01

Fecal coliforms, Escherichia coli, enterococci, and somatic coliphages were detected in samples from 31 sites on streams draining urban and agricultural regions of the Puget Sound Basin Lowlands. Densities of bacteria in 48 and 71 percent of the samples exceeded U.S. Environmental Protection Agency's freshwater recreation criteria for Escherichia coli and enterococci, respectively, and 81 percent exceeded Washington State fecal coliform standards. Male-specific coliphages were detected in samples from 15 sites. Male-specific F+RNA coliphages isolated from samples taken at South Fork Thornton and Longfellow Creeks were serotyped as Group II, implicating humans as potential contaminant sources. These two sites are located in residential, urban areas. F+RNA coliphages in samples from 10 other sites, mostly in agricultural or rural areas, were serotyped as Group I, implicating non-human animals as likely sources. Chemicals common to wastewater, including fecal sterols, were detected in samples from several urban streams, and also implicate humans, at least in part, as possible sources of fecal bacteria and viruses to the streams.

Impact of emissions from natural gas production facilities on ambient air quality in the Barnett Shale area: a pilot study.

PubMed

Zielinska, Barbara; Campbell, Dave; Samburova, Vera

2014-12-01

Rapid and extensive development of shale gas resources in the Barnett Shale region of Texas in recent years has created concerns about potential environmental impacts on water and air quality. The purpose of this study was to provide a better understanding of the potential contributions of emissions from gas production operations to population exposure to air toxics in the Barnett Shale region. This goal was approached using a combination of chemical characterization of the volatile organic compound (VOC) emissions from active wells, saturation monitoring for gaseous and particulate pollutants in a residential community located near active gas/oil extraction and processing facilities, source apportionment of VOCs measured in the community using the Chemical Mass Balance (CMB) receptor model, and direct measurements of the pollutant gradient downwind of a gas well with high VOC emissions. Overall, the study results indicate that air quality impacts due to individual gas wells and compressor stations are not likely to be discernible beyond a distance of approximately 100 m in the downwind direction. However, source apportionment results indicate a significant contribution to regional VOCs from gas production sources, particularly for lower-molecular-weight alkanes (< C6). Although measured ambient VOC concentrations were well below health-based safe exposure levels, the existence of urban-level mean concentrations of benzene and other mobile source air toxics combined with soot to total carbon ratios that were high for an area with little residential or commercial development may be indicative of the impact of increased heavy-duty vehicle traffic related to gas production. Implications: Rapid and extensive development of shale gas resources in recent years has created concerns about potential environmental impacts on water and air quality. This study focused on directly measuring the ambient air pollutant levels occurring at residential properties located near natural gas extraction and processing facilities, and estimating the relative contributions from gas production and motor vehicle emissions to ambient VOC concentrations. Although only a small-scale case study, the results may be useful for guidance in planning future ambient air quality studies and human exposure estimates in areas of intensive shale gas production.

Soybean hulls as an iron source for bread enrichment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, C.D.; Berry, M.F.; Weaver, C.M.

Soybean hulls, a concentrated source of iron, may have potential as a source of iron fortification in baked products. Retention of /sup 59/Fe in rats from white bread containing intrinsically labeled soybean hulls did not differ significantly (p<0.05) from extrinsically labeled white bread fortified with bakery grade ferrous sulfate (70.4 and 63.1%, respectively). Physical and sensory evaluations of bread containing up to 5% soybean hulls did not differ from white bread in loaf volume, cross-sectional area, tenderness or overall acceptance. These results suggest that soybean hulls are a good source of available iron and may be added to bakery productsmore » without deleterious effects in baking performance and sensory acceptability.« less

Calculating solar photovoltaic potential on residential rooftops in Kailua Kona, Hawaii

NASA Astrophysics Data System (ADS)

Carl, Caroline

As carbon based fossil fuels become increasingly scarce, renewable energy sources are coming to the forefront of policy discussions around the globe. As a result, the State of Hawaii has implemented aggressive goals to achieve energy independence by 2030. Renewable electricity generation using solar photovoltaic technologies plays an important role in these efforts. This study utilizes geographic information systems (GIS) and Light Detection and Ranging (LiDAR) data with statistical analysis to identify how much solar photovoltaic potential exists for residential rooftops in the town of Kailua Kona on Hawaii Island. This study helps to quantify the magnitude of possible solar photovoltaic (PV) potential for Solar World SW260 monocrystalline panels on residential rooftops within the study area. Three main areas were addressed in the execution of this research: (1) modeling solar radiation, (2) estimating available rooftop area, and (3) calculating PV potential from incoming solar radiation. High resolution LiDAR data and Esri's solar modeling tools and were utilized to calculate incoming solar radiation on a sample set of digitized rooftops. Photovoltaic potential for the sample set was then calculated with the equations developed by Suri et al. (2005). Sample set rooftops were analyzed using a statistical model to identify the correlation between rooftop area and lot size. Least squares multiple linear regression analysis was performed to identify the influence of slope, elevation, rooftop area, and lot size on the modeled PV potential values. The equations built from these statistical analyses of the sample set were applied to the entire study region to calculate total rooftop area and PV potential. The total study area statistical analysis findings estimate photovoltaic electric energy generation potential for rooftops is approximately 190,000,000 kWh annually. This is approximately 17 percent of the total electricity the utility provided to the entire island in 2012. Based on these findings, full rooftop PV installations on the 4,460 study area homes could provide enough energy to power over 31,000 homes annually. The methods developed here suggest a means to calculate rooftop area and PV potential in a region with limited available data. The use of LiDAR point data offers a major opportunity for future research in both automating rooftop inventories and calculating incoming solar radiation and PV potential for homeowners.

Fishery Household (FH) database and cultivation areas in Indramayu regency to develop Shrimp and Milkfish farming based on GIS

NASA Astrophysics Data System (ADS)

Rostika, Rita; Purba, Noir P.; Iskandar; Paradhita Dewanti, Lantun; Mahdiana Apriliani, Izza

2018-05-01

With a coastline length of 114 km, the utilization of the coastline areas is potential for especially shrimp and milkfish cultivations, which have a higher economic value. However, appropriate development strategies are highly required. The purpose of this research is to examine the existing conditions and organize integrated information for fishery household as well as the areas utilized for shrimp and milkfish cultivations, especially in coastal areas. The methods used include an analysis from Landsat 8 imaginary, field survey, and interviews with various sources. This research conducted in June-November 2015. Data from remote sensing were digitized and utilized as mark point to survey area of cultivation. The results show that the distributions of RTP data cover Windu and Vaname shrimp polycultures by 1,727 RTP, milkfish by 1,551 RTP, Vaname shrimp by 2,953 RTP, and Windu Shrimp by 88 RTP. The area, which may be utilized as ponds, is 9,854.1 ha. The area for milkfish ponds is 12,065.08 ha, while the digitation result is 10,801.92 ha. It shows that Indramayu coastal areas still have numerous and various potentials, which may be utilized for shrimp and milkfish cultivations.

Breakdown of local information processing may underlie isoflurane anesthesia effects.

PubMed

Wollstadt, Patricia; Sellers, Kristin K; Rudelt, Lucas; Priesemann, Viola; Hutt, Axel; Fröhlich, Flavio; Wibral, Michael

2017-06-01

The disruption of coupling between brain areas has been suggested as the mechanism underlying loss of consciousness in anesthesia. This hypothesis has been tested previously by measuring the information transfer between brain areas, and by taking reduced information transfer as a proxy for decoupling. Yet, information transfer is a function of the amount of information available in the information source-such that transfer decreases even for unchanged coupling when less source information is available. Therefore, we reconsidered past interpretations of reduced information transfer as a sign of decoupling, and asked whether impaired local information processing leads to a loss of information transfer. An important prediction of this alternative hypothesis is that changes in locally available information (signal entropy) should be at least as pronounced as changes in information transfer. We tested this prediction by recording local field potentials in two ferrets after administration of isoflurane in concentrations of 0.0%, 0.5%, and 1.0%. We found strong decreases in the source entropy under isoflurane in area V1 and the prefrontal cortex (PFC)-as predicted by our alternative hypothesis. The decrease in source entropy was stronger in PFC compared to V1. Information transfer between V1 and PFC was reduced bidirectionally, but with a stronger decrease from PFC to V1. This links the stronger decrease in information transfer to the stronger decrease in source entropy-suggesting reduced source entropy reduces information transfer. This conclusion fits the observation that the synaptic targets of isoflurane are located in local cortical circuits rather than on the synapses formed by interareal axonal projections. Thus, changes in information transfer under isoflurane seem to be a consequence of changes in local processing more than of decoupling between brain areas. We suggest that source entropy changes must be considered whenever interpreting changes in information transfer as decoupling.

Large area full-field optical coherence tomography using white light source

NASA Astrophysics Data System (ADS)

Chang, Shoude; Mao, Youxin; Sherif, Sherif; Flueraru, Costel

2007-06-01

Optical coherence tomography (OCT) is an emerging technology for high-resolution cross-sectional imaging of 3D structures. Not only could OCT extract the internal features of an object, but it could acquire the 3D profile of an object as well. Hence it has huge potentials for industrial applications. Owing to non-scanning along the X-Y axis, full-field OCT could be the simplest and most economic imaging system, especially for applications where the speed is critical. For an OCT system, the performance and cost basically depends on the light source being used. The broader the source bandwidth, the finer of the depth resolution that could be reached; the more power of the source, the better signal-to-noise ratio and the deeper of penetration the system achieves. A typical SLD (Superluminescent Diode) light source has a bandwidth of 15 nm and 10 mW optical power at a price around 6,000. However, a Halogen bulb having 50W power and 200nm bandwidth only costs less than 10. The design and implementation of a large-area, full-field OCT system using Halogen white-light source is described in the paper. The experimental results obtained from 3D shaping and multiple-layer tomographies are also presented.

Identification of Blood Meals from Potential Arbovirus Mosquito Vectors in the Peruvian Amazon Basin

PubMed Central

Palermo, Pedro M.; Aguilar, Patricia V.; Sanchez, Juan F.; Zorrilla, Víctor; Flores-Mendoza, Carmen; Huayanay, Anibal; Guevara, Carolina; Lescano, Andrés G.; Halsey, Eric S.

2016-01-01

The transmission dynamics of many arboviruses in the Amazon Basin region have not been fully elucidated, including the vectors and natural reservoir hosts. Identification of blood meal sources in field-caught mosquitoes could yield information for identifying potential arbovirus vertebrate hosts. We identified blood meal sources in 131 mosquitoes collected from areas endemic for arboviruses in the Peruvian Department of Loreto by sequencing polymerase chain reaction amplicons of the cytochrome b gene. Psorophora (Janthinosoma) albigenu, Psorophora (Grabhamia) cingulata, Mansonia humeralis, Anopheles oswaldoi s.l., and Anopheles benarrochi s.l. had mainly anthropophilic feeding preferences; Aedes (Ochlerotatus) serratus, and Aedes (Ochlerotatus) fulvus had feeding preferences for peridomestic animals; and Culex (Melanoconion) spp. fed on a variety of vertebrates, mainly rodents (spiny rats), birds, and amphibians. On the basis of these feeding preferences, many mosquitoes could be considered as potential enzootic and bridge arbovirus vectors in the Amazon Basin of Peru. PMID:27621304

Theobroma cacao: Review of the Extraction, Isolation, and Bioassay of Its Potential Anti-cancer Compounds

PubMed Central

Baharum, Zainal; Akim, Abdah Md; Hin, Taufiq Yap Yun; Hamid, Roslida Abdul; Kasran, Rosmin

2016-01-01

Plants have been a good source of therapeutic agents for thousands of years; an impressive number of modern drugs used for treating human diseases are derived from natural sources. The Theobroma cacao tree, or cocoa, has recently garnered increasing attention and become the subject of research due to its antioxidant properties, which are related to potential anti-cancer effects. In the past few years, identifying and developing active compounds or extracts from the cocoa bean that might exert anti-cancer effects have become an important area of health- and biomedicine-related research. This review provides an updated overview of T. cacao in terms of its potential anti-cancer compounds and their extraction, in vitro bioassay, purification, and identification. This article also discusses the advantages and disadvantages of the techniques described and reviews the processes for future perspectives of analytical methods from the viewpoint of anti-cancer compound discovery. PMID:27019680

Integrating future scenario‐based crop expansion and crop conditions to map switchgrass biofuel potential in eastern Nebraska, USA

USGS Publications Warehouse

Gu, Yingxin; Wylie, Bruce K.

2018-01-01

Switchgrass (Panicum virgatum) has been evaluated as one potential source for cellulosic biofuel feedstocks. Planting switchgrass in marginal croplands and waterway buffers can reduce soil erosion, improve water quality, and improve regional ecosystem services (i.e. it serves as a potential carbon sink). In previous studies, we mapped high risk marginal croplands and highly erodible cropland buffers that are potentially suitable for switchgrass development, which would improve ecosystem services and minimally impact food production. In this study, we advance our previous study results and integrate future crop expansion information to develop a switchgrass biofuel potential ensemble map for current and future croplands in eastern Nebraska. The switchgrass biomass productivity and carbon benefits (i.e. NEP: net ecosystem production) for the identified biofuel potential ensemble areas were quantified. The future scenario‐based (‘A1B’) land use and land cover map for 2050, the US Geological Survey crop type and Compound Topographic Index (CTI) maps, and long‐term (1981–2010) averaged annual precipitation data were used to identify future crop expansion regions that are suitable for switchgrass development. Results show that 2528 km2 of future crop expansion regions (~3.6% of the study area) are potentially suitable for switchgrass development. The total estimated biofuel potential ensemble area (including cropland buffers, marginal croplands, and future crop expansion regions) is 4232 km2 (~6% of the study area), potentially producing 3.52 million metric tons of switchgrass biomass per year. Converting biofuel ensemble regions to switchgrass leads to potential carbon sinks (the total NEP for biofuel potential areas is 0.45 million metric tons C) and is environmentally sustainable. Results from this study improve our understanding of environmental conditions and ecosystem services of current and future cropland systems in eastern Nebraska and provide useful information to land managers to make land use decisions regarding switchgrass development.

Characterization, distribution, and risk assessment of heavy metals in agricultural soil and products around mining and smelting areas of Hezhang, China.

PubMed

Briki, Meryem; Ji, Hongbing; Li, Cai; Ding, Huaijian; Gao, Yang

2015-12-01

Mining and smelting have been releasing huge amount of toxic substances into the environment. In the present study, agricultural soil and different agricultural products (potato, Chinese cabbage, garlic bolt, corn) were analyzed to examine the source, spatial distribution, and risk of 12 elements (As, Be, Bi, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, and Zn) in agricultural soil near mine fields, smelting fields, and mountain field around Hezhang County, west of Guizhou Province, China. Multivariate statistical analysis indicated that in mining area, As, Bi, Cd, Cu, Hg, Pb, Sb, and Zn were generated from anthropogenic sources; in smelting area, As, Be, Cd, Co, Cu, Pb, Sb, and Zn were derived from anthropogenic sources through zinc smelting ceased in 2004. The enrichment factors (EFs) and ecological risk index (RI) of soil in mining area are the most harmful, showing extremely high enrichment and very high ecological risk of As, Bi, Cd, Cu, Hg, Pb, Sb, and Zn. Zinc is the most significant enriched in the smelting area; however, mountain area has a moderate enrichment and ecological risk and do not present any ecological risk. According to spatial distribution, the concentrations depend on the nearby mining and smelting activities. Transfer factors (TFs) in the smelting area and mountain are high, implying a threat for human consumption. Therefore, further studies should be carried out taking into account the harm of those heavy metals and potential negative health effects from the consumption of agricultural products in these circumstances.

Pointing to potential reference areas to assess soil mutagenicity.

PubMed

Meyer, D D; Da Silva, F M R; Souza, J W M; Pohren, R S; Rocha, J A V; Vargas, V M F

2015-04-01

Several have been performed to evaluate the mutagenicity of soil samples in urban and industrial areas. The use of uncontaminated reference areas has been an obstacle to the study of environmental mutagenesis. The study aimed to indicate a methodology to define reference areas in studies of environmental contamination based on "Ambient Background Concentration" of metallic elements associated with the Salmonella/microsome assay. We looked at three potential reference areas, two of them close by the industrial sources of contamination (São Jerônimo reference, near the coal-fired power plant, and Triunfo reference, near the wood preservative plant), but not directly influenced by them and an area located inside a protected area (Itapuã reference). We also carried out chemical analyses of some metals to plot the metal profile of these potential reference areas and define basal levels of these metals in the soils. After examining the mutagenicity of the inorganic extracts using strains TA98, TA97a, and TA100, in the presence and absence of S9 mix, we indicated the São Jerônimo reference and the Itapuã reference as two sites that could be used in future studies of mutagenicity of soils in southern Brazil. The association between a mutagenicity bioassay and the "Ambient Background Concentration" seems to be a useful method to indicate the reference areas in studies of contamination by environmental mutagens, where these results were corroborated by canonical correspondence analysis.

[Correlating landscape pattern with total nitrogen concentration using a location-weighted sink-source landscape index in the Haihe River Basin, China].

PubMed

Sun, Ran-Hao; Chen, Li-Ding; Wang, Wei; Wang, Zhao-Ming

2012-06-01

Understanding the effect of land cover pattern on nutrient losses is of great importance in management of water resources. The extensive application of mechanism models is limited in large-scale watersheds owing to the intensive data and calibration requirements. On the other hand, the traditional landscape indexes only take the areas and types of land cover into account, considering less about their topographic features and spatial patterns. We constructed a location-weighted landscape index (LWLI) based on the Lorenz curve, which plots the cumulative proportion of areas for sink and source landscapes respectively against cumulative proportion of their relative location to the outlet in a watershed, including relative elevation, distance and slope. We assessed the effect of land cover pattern on total nitrogen losses in the Haihe River. Firstly, 26 watersheds were derived from 1: 250 000 digital elevation model (DEM), and their "source" and "sink" landscape types were identified from Landsat TM images in 2007. The source" landscapes referred to the paddy land, dry land and residential area, correspondingly the "sink" landscapes referred to the forest and grassland. Secondly, LWLI was calculated according to the landscape types and spatial patterns for each watershed. Thirdly, we accessed the effect of land cover pattern on total nitrogen (TN) flux according to the value of LWLI, comparing with the area proportion of sink-source landscapes. The correlation coefficients were different in three parts of Haihe River, i. e., 0.86, 0.67 and 0.65 in the Yanshan Mts, Taihang Mts and lower Haihe River. The results showed strong correlations between TN and LWLI in contrast to the weak correlations between TN and area proportion of sink and source landscape types. This study indicates the spatial pattern of land cover is essential for accessing the nutrient losses, and the location-weighted landscape pattern analysis may be an alternate to existing water quality models, especially in large watershed scales. The sink-source index is sufficiently simple that it can be compared across watersheds and be easily interpreted, and potentially be used in landscape pattern optimal designing and planning.

Patterns and age distribution of ground-water flow to streams

USGS Publications Warehouse

Modica, E.; Reilly, T.E.; Pollock, D.W.

1997-01-01

Simulations of ground-water flow in a generic aquifer system were made to characterize the topology of ground-water flow in the stream subsystem and to evaluate its relation to deeper ground-water flow. The flow models are patterned after hydraulic characteristics of aquifers of the Atlantic Coastal Plain and are based on numerical solutions to three-dimensional, steady-state, unconfined flow. The models were used to evaluate the effects of aquifer horizontal-to-vertical hydraulic conductivity ratios, aquifer thickness, and areal recharge rates on flow in the stream subsystem. A particle tracker was used to determine flow paths in a stream subsystem, to establish the relation between ground-water seepage to points along a simulated stream and its source area of flow, and to determine ground-water residence time in stream subsystems. In a geometrically simple aquifer system with accretion, the source area of flow to streams resembles an elongated ellipse that tapers in the downgradient direction. Increased recharge causes an expansion of the stream subsystem. The source area of flow to the stream expands predominantly toward the stream headwaters. Baseflow gain is also increased along the reach of the stream. A thin aquifer restricts ground-water flow and causes the source area of flow to expand near stream headwaters and also shifts the start-of-flow to the drainage basin divide. Increased aquifer anisotropy causes a lateral expansion of the source area of flow to streams. Ground-water seepage to the stream channel originates both from near- and far-recharge locations. The range in the lengths of flow paths that terminate at a point on a stream increase in the downstream direction. Consequently, the age distribution of ground water that seeps into the stream is skewed progressively older with distance downstream. Base flow ia an integration of ground water with varying age and potentially different water quality, depending on the source within the drainage basin. The quantitative results presented indicate that this integration can have a wide and complex residence time range and source distribution.

Electrochemical current noise on aluminum microelectrodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Isaac, J.W.; Hebert, K.R.

1999-02-01

Aluminum disk microelectrodes were used to investigate electrochemical current noise in pH 8.8 borate buffer. The current noise spectra, expressed in terms of the current spectral density, had a characteristic two-plateau structure in the experimental bandwidth of 0.05--50 Hz, were potential-independent, and increased proportionally to electrode area. Injection of NaCl solution near the electrode surface, at potentials below that of the onset of pitting corrosion, caused 0.1--1 Hz current fluctuations to appear. From the frequency and area dependence of the current spectral density in the chloride-free solution, it was concluded that the noise arose from a number of discrete, approximatelymore » evenly distributed voltage noise sources positioned electrically in series with the inner barrier layer of the oxide film. A mathematical model for the current noise was developed which described a physical mechanism for noise production based on fluctuations in the widths of cracks or pores in the outer part of the surface film. The model was consistent with the observed area and frequency dependence of the current spectral density, suggesting that the physical process it described is a possible mechanism of noise generation. It could not be determined whether the noise sources were isolated defects or flaws, or pores in an outer precipitated portion of the oxide film.« less

Seismic stability of the survey areas of potential sites for the deep geological repository of the spent nuclear fuel

NASA Astrophysics Data System (ADS)

Kaláb, Zdeněk; Šílený, Jan; Lednická, Markéta

2017-07-01

This paper deals with the seismic stability of the survey areas of potential sites for the deep geological repository of the spent nuclear fuel in the Czech Republic. The basic source of data for historical earthquakes up to 1990 was the seismic website [1-]. The most intense earthquake described occurred on September 15, 1590 in the Niederroesterreich region (Austria) in the historical period; its reported intensity is Io = 8-9. The source of the contemporary seismic data for the period since 1991 to the end of 2014 was the website [11]. It may be stated based on the databases and literature review that in the period from 1900, no earthquake exceeding magnitude 5.1 originated in the territory of the Czech Republic. In order to evaluate seismicity and to assess the impact of seismic effects at depths of hypothetical deep geological repository for the next time period, the neo-deterministic method was selected as an extension of the probabilistic method. Each one out of the seven survey areas were assessed by the neo-deterministic evaluation of the seismic wave-field excited by selected individual events and determining the maximum loading. Results of seismological databases studies and neo-deterministic analysis of Čihadlo locality are presented.

Petroleum Systems and Geologic Assessment of Undiscovered Oil and Gas, Navarro and Taylor Groups, Western Gulf Province, Texas

USGS Publications Warehouse

,

2006-01-01

The purpose of the U.S. Geological Survey's (USGS) National Oil and Gas Assessment is to develop geologically based hypotheses regarding the potential for additions to oil and gas reserves in priority areas of the United States. The USGS recently completed an assessment of undiscovered oil and gas potential of the Late Cretaceous Navarro and Taylor Groups in the Western Gulf Province in Texas (USGS Province 5047). The Navarro and Taylor Groups have moderate potential for undiscovered oil resources and good potential for undiscovered gas resources. This assessment is based on geologic principles and uses the total petroleum system concept. The geologic elements of a total petroleum system include hydrocarbon source rocks (source rock maturation, hydrocarbon generation and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and hydrocarbon traps (trap formation and timing). The USGS used this geologic framework to define one total petroleum system and five assessment units. Five assessment units were quantitatively assessed for undiscovered oil and gas resources.

Resistivity and self-potential tomography applied to groundwater remediation and contaminant plumes: Sandbox and field experiments

NASA Astrophysics Data System (ADS)

Mao, D.; Revil, A.; Hort, R. D.; Munakata-Marr, J.; Atekwana, E. A.; Kulessa, B.

2015-11-01

Geophysical methods can be used to remotely characterize contaminated sites and monitor in situ enhanced remediation processes. We have conducted one sandbox experiment and one contaminated field investigation to show the robustness of electrical resistivity tomography and self-potential (SP) tomography for these applications. In the sandbox experiment, we injected permanganate in a trichloroethylene (TCE)-contaminated environment under a constant hydraulic gradient. Inverted resistivity tomograms are able to track the evolution of the permanganate plume in agreement with visual observations made on the side of the tank. Self-potential measurements were also performed at the surface of the sandbox using non-polarizing Ag-AgCl electrodes. These data were inverted to obtain the source density distribution with and without the resistivity information. A compact horizontal dipole source located at the front of the plume was obtained from the inversion of these self-potential data. This current dipole may be related to the redox reaction occurring between TCE and permanganate and the strong concentration gradient at the front of the plume. We demonstrate that time-lapse self-potential signals can be used to track the kinetics of an advecting oxidizer plume with acceptable accuracy and, if needed, in real time, but are unable to completely resolve the shape of the plume. In the field investigation, a 3D resistivity tomography is used to characterize an organic contaminant plume (resistive domain) and an overlying zone of solid waste materials (conductive domain). After removing the influence of the streaming potential, the identified source current density had a magnitude of 0.5 A m-2. The strong source current density may be attributed to charge movement between the neighboring zones that encourage abiotic and microbially enhanced reduction and oxidation reactions. In both cases, the self-potential source current density is located in the area of strong resistivity gradient.

7 CFR 1.412 - Institution of proceedings.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Adjudication of Sourcing Area Applications and Formal Review of Sourcing Areas Pursuant to the Forest Resources...) Sourcing area applications. The proceeding for determining sourcing areas shall be instituted by receipt of a sourcing area application by the Office of Administrative Law Judges, pursuant to 36 CFR 223.190...

7 CFR 1.411 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Sourcing area applicant means a person who submits a sourcing area application pursuant to these rules, or a person who sourcing area is subject to formal review pursuant to 36 CFR 223.191(e). (b) Decision... Sourcing Area Applications and Formal Review of Sourcing Areas Pursuant to the Forest Resources...

BTEX exposures in an area impacted by industrial and mobile sources: Source attribution and impact of averaging time.

PubMed

Presto, Albert A; Dallmann, Timothy R; Gu, Peishi; Rao, Unnati

2016-04-01

The impacts of emissions plumes from major industrial sources on black carbon (BC) and BTEX (benzene, toluene, ethyl benzene, xylene isomers) exposures in communities located >10 km from the industrial source areas were identified with a combination of stationary measurements, source identification using positive matrix factorization (PMF), and dispersion modeling. The industrial emissions create multihour plume events of BC and BTEX at the measurement sites. PMF source apportionment, along with wind patterns, indicates that the observed pollutant plumes are the result of transport of industrial emissions under conditions of low boundary layer height. PMF indicates that industrial emissions contribute >50% of outdoor exposures of BC and BTEX species at the receptor sites. Dispersion modeling of BTEX emissions from known industrial sources predicts numerous overnight plumes and overall qualitative agreement with PMF analysis, but predicts industrial impacts at the measurement sites a factor of 10 lower than PMF. Nonetheless, exposures associated with pollutant plumes occur mostly at night, when residents are expected to be home but are perhaps unaware of the elevated exposure. Averaging data samples over long times typical of public health interventions (e.g., weekly or biweekly passive sampling) misapportions the exposure, reducing the impact of industrial plumes at the expense of traffic emissions, because the longer samples cannot resolve subdaily plumes. Suggestions are made for ways for future distributed pollutant mapping or intervention studies to incorporate high time resolution tools to better understand the potential impacts of industrial plumes. Emissions from industrial or other stationary sources can dominate air toxics exposures in communities both near the source and in downwind areas in the form of multihour plume events. Common measurement strategies that use highly aggregated samples, such as weekly or biweekly averages, are insensitive to such plume events and can lead to significant under apportionment of exposures from these sources.

Source analysis of particulate matter associated polycyclic aromatic hydrocarbons (PAHs) in an industrial city in northeastern China.

PubMed

Han, Bin; Ding, Xiao; Bai, Zhipeng; Kong, Shaofei; Guo, Guanghuan

2011-09-01

Particle-associated polycyclic aromatic hydrocarbon (PAH) concentrations were investigated at eight sampling sites during cold periods where heating is used (heating period) (February to March, 2005) and warm periods where heating is not required (non-heating periods) (August to September 2006) in the urban area of Anshan, an iron and steel city in northeastern China. Eleven PAH species were measured using GC-MS. The total average concentrations of PAHs ranged from 46.14 to 385.60 ng m(-3) in the heating period and from 5.28 to 146.40 ng m(-3) in the non-heating period. The lowest concentration of ∑PAHs was observed at Qianshan, a monitoring site far from the city and industrial area, and the highest concentration occurred in the site located at the factory area of Anshan Iron and Steel Incorporation. Moreover, ambient PAH profiles were studied and high molecular weight PAH (including 4-6 rings) species occurred in the high fractions. Toxic equivalent factors analysis gave the potential carcinogenic risks in Anshan. For the heating sampling period, BaP equivalent concentration is in the range of 41.98 to 220.83 ng m(-3), and 9.23 to 126.00 ng m(-3) for the non-heating sampling period. By diagnostic ratio analysis, traffic emission and combustion (coal or biomass) were potential sources for PAHs in Anshan. Finally, PCA results indicated the major sources were vehicle emission, steel industry emission, and coal combustion for both heating and non-heating seasons, which agreed with the results from the diagnostic ratio analysis.

Wood to energy: using southern interface fuels for bioenergy

Treesearch

C. Staudhammer; L.A. Hermansen; D. Carter; Ed Macie

2011-01-01

This publications aims to increase awareness of potential uses for woody biomass in the southern wildland-urban interface (WUI) and to disseminate knowledge about putting bioenergy production systems in place, while addressing issues unique to WUI areas. Chapter topics include woody biomass sources in the wildland-urban interface; harvesting, preprocessing and delivery...

PERSONAL PARTICULATE MATTER EXPOSURE MONITORING: IDENTIFYING IMPORTANT SOURCES, ACTIVITIES, AND LOCATIONS BASED ON DATA FROM THE NERL RTP PM PANEL STUDY

EPA Science Inventory

A longitudinal particulate matter (PM) exposure study was conducted in the Research Triangle Park, NC area between June 2000 and June 2001. Participants were selected from two groups of potentially susceptible sub-populations: a group of African-Americans living in an environme...

The National Assessment Approach to Objectives and Exercise Development.

ERIC Educational Resources Information Center

Ward, Barbara

The National Assessment of Educational Progress (NAEP) item development procedures, possible improvements or alternatives to these procedures, and methods used to control potential sources of errors of interpretation are described. Current procedures call for the assessment of 9-, 13- and 17-year-olds in subject areas typically taught in schools.…

Evaluating the influence of wind speed on caryopsis dispersal of Miscanthus sinensis and Miscanthus x. giganteus

USDA-ARS?s Scientific Manuscript database

With the increasing demand for alternative energy sources, perennial grasses are being evaluated for biomass production on large scales. Yet there is concern that some candidate species have the potential to escape cultivation and invade natural areas. Therefore, it is important that components of...

Collaboration between Special and Physical Education: The Benefits of a Healthy Lifestyle for All Students

ERIC Educational Resources Information Center

Klein, Emily; Hollingshead, Aleksandra

2015-01-01

Physical education (PE) has holistic benefits for all students, including those with disabilities, as it supports the development of three critical learning areas: cognitive, psychomotor, and affective ("Adapted Physical Education," 2012; Bailey, 2006; Burgeson, 2004). PE is potentially the main source of physical activity and the…

Combining accuracy assessment of land-cover maps with environmental monitoring programs

Treesearch

Stephen V. Stehman; Raymond L. Czaplewski; Sarah M. Nusser; Limin Yang; Zhiliang Zhu

2000-01-01

A scientifically valid accuracy assessment of a large-area, land-cover map is expensive. Environmental monitoring programs offer a potential source of data to partially defray the cost of accuracy assessment while still maintaining the statistical validity. In this article, three general strategies for combining accuracy assessment and environmental monitoring...

Visual management system and timber management application

Treesearch

Warren R. Bacon; Asa D. (Bud) Twombly

1979-01-01

This paper includes an illustration of a planning process to guide vegetation management throughout a travel route seen area and over the time period of a total management rotation (100-300 years). The process will produce direction on visual characteristics to be created and maintained within the biological potential and coordinated with associated re-source...

Managing to Survive/Succeed: Potentials Within the Library Organization. 1981 LACUNY Institute Bibliography.

ERIC Educational Resources Information Center

Penchansky, Mimi B.; And Others

Prepared for the 1981 Spring Institute of the Library Association of City University of New York (LACUNY), this bibliography lists sources on academic library management techniques. Its three sections encompass the following areas: (1) the individual's relationship to the library organization, (2) effective management of time, and (3) human…

76 FR 12715 - Magnuson-Stevens Act Provisions; General Provisions for Domestic Fisheries; Application for...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-08

... and marketing evaluation and strategies; and outreach and implementation of the project results. The... devise strategies and means to efficiently harvest the redfish resource in the Gulf of Maine (GOM) while... in terms of their potential effects on results. Sources of variability include: Area fished; seasonal...

Extreme Precipitation and Emergency Room Visits for Gastrointestinal Illness in Areas With and Without Combined Sewer Systems: An Analysis of Massachusetts Data, 2003-2007

EPA Science Inventory

Background: Combined sewer overflows (CSOs) occur in combined sewer systems when sewage and stormwater runoff discharge into waterbodies potentially contaminating water sources. CSOs are often caused by heavy precipitation and are expected to increase with increasing extreme pre...

A landscape-based reconnaissance survey of estrogenic activity in streams of the upper Potomac, upper James, and Shenandoah Rivers, USA.

PubMed

Young, John; Iwanowicz, Luke; Sperry, Adam; Blazer, Vicki

2014-09-01

Endocrine-disrupting compounds (EDCs) are becoming of increasing concern in waterways of the USA and worldwide. What remains poorly understood, however, is how prevalent these emerging contaminants are in the environment and what methods are best able to determine landscape sources of EDCs. We describe the development of a spatially structured sampling design and a reconnaissance survey of estrogenic activity along gradients of land use within sub-watersheds. We present this example as a useful approach for state and federal agencies with an interest in identifying locations potentially impacted by EDCs that warrant more intensive, focused research. Our study confirms the importance of agricultural activities on levels of a measured estrogenic equivalent (E2Eq) and also highlights the importance of other potential sources of E2Eq in areas where intensive agriculture is not the dominant land use. Through application of readily available geographic information system (GIS) data, coupled with spatial statistical analysis, we demonstrate the correlation of specific land use types to levels of estrogenic activity across a large area in a consistent and unbiased manner.

The potential of high heat generating granites as EGS source to generate power and reduce CO2 emissions, western Arabian shield, Saudi Arabia

NASA Astrophysics Data System (ADS)

Chandrasekharam, D.; Lashin, A.; Al Arifi, N.; Al Bassam, A.; El Alfy, M.; Ranjith, P. G.; Varun, C.; Singh, H. K.

2015-12-01

Saudi Arabia's dependence on oil and gas to generate electricity and to desalinate sea water is widely perceived to be economically and politically unsustainable. A recent business as usual simulation concluded that the Kingdom would become an oil importer by 2038. There is an opportunity for the country to over come this problem by using its geothermal energy resources. The heat flow and heat generation values of the granites spread over a cumulative area of 161,467 sq. km and the regional stress regime over the western Saudi Arabian shield strongly suggest that this entire area is potential source of energy to support 1) electricity generation, 2) fresh water generation through desalination and 3) extensive agricultural activity for the next two decades. The country can adopt a policy to harness this vast untapped enhanced geothermal systems (EGS) to mitigate climate and fresh water related issues and increase the quantity of oil for export. The country has inherent expertise to develop this resource.

A landscape-based reconnaissance survey of estrogenicactivity in streams of the upper Potomac, upper James,and Shenandoah Rivers, USA

USGS Publications Warehouse

Young, John A.; Iwanowicz, Luke R.; Sperry, Adam J.; Blazer, Vicki

2014-01-01

Endocrine-disrupting compounds (EDCs) are becoming of increasing concern in waterways of the USA and worldwide. What remains poorly understood, however, is how prevalent these emerging contaminants are in the environment and what methods are best able to determine landscape sources of EDCs. We describe the development of a spatially structured sampling design and a reconnaissance survey of estrogenic activity along gradients of land use within sub-watersheds.We present this example as a useful approach for state and federal agencies with an interest in identifying locations potentially impacted by EDCs that warrant more intensive, focused research. Our study confirms the importance of agricultural activities on levels of a measured estrogenic equivalent (E2Eq) and also highlights the importance of other potential sources of E2Eq in areas where intensive agriculture is not the dominant land use. Through application of readily available geographic information system (GIS) data, coupled with spatial statistical analysis, we demonstrate the correlation of specific land use types to levels of estrogenic activity across a large area in a consistent and unbiased manner.

Edge detection of magnetic anomalies using analytic signal of tilt angle (ASTA)

NASA Astrophysics Data System (ADS)

Alamdar, K.; Ansari, A. H.; Ghorbani, A.

2009-04-01

Magnetic is a commonly used geophysical technique to identify and image potential subsurface targets. Interpretation of magnetic anomalies is a complex process due to the superposition of multiple magnetic sources, presence of geologic and cultural noise and acquisition and positioning error. Both the vertical and horizontal derivatives of potential field data are useful; horizontal derivative, enhance edges whereas vertical derivative narrow the width of anomaly and so locate source bodies more accurately. We can combine vertical and horizontal derivative of magnetic field to achieve analytic signal which is independent to body magnetization direction and maximum value of this lies over edges of body directly. Tilt angle filter is phased-base filter and is defined as angle between vertical derivative and total horizontal derivative. Tilt angle value differ from +90 degree to -90 degree and its zero value lies over body edge. One of disadvantage of this filter is when encountering with deep sources the detected edge is blurred. For overcome this problem many authors introduced new filters such as total horizontal derivative of tilt angle or vertical derivative of tilt angle which Because of using high-order derivative in these filters results may be too noisy. If we combine analytic signal and tilt angle, a new filter termed (ASTA) is produced which its maximum value lies directly over body edge and is easer than tilt angle to delineate body edge and no complicity of tilt angle. In this work new filter has been demonstrated on magnetic data from an area in Sar- Cheshme region in Iran. This area is located in 55 degree longitude and 32 degree latitude and is a copper potential region. The main formation in this area is Andesith and Trachyandezite. Magnetic surveying was employed to separate the boundaries of Andezite and Trachyandezite from adjacent area. In this regard a variety of filters such as analytic signal, tilt angle and ASTA filter have been applied which new ASTA filter determined Andezite boundaries from surrounded more accurately than other filters. Keywords: Horizontal derivative, Vertical derivative, Tilt angle, Analytic signal, ASTA, Sar-Cheshme.

Harvesting rockfall hazard evaluation parameters from Google Earth Street View

NASA Astrophysics Data System (ADS)

Partsinevelos, Panagiotis; Agioutantis, Zacharias; Tripolitsiotis, Achilles; Steiakakis, Chrysanthos; Mertikas, Stelios

2015-04-01

Rockfall incidents along highways and railways prove extremely dangerous for properties, infrastructures and human lives. Several qualitative metrics such as the Rockfall Hazard Rating System (RHRS) and the Colorado Rockfall Hazard Rating System (CRHRS) have been established to estimate rockfall potential and provide risk maps in order to control and monitor rockfall incidents. The implementation of such metrics for efficient and reliable risk modeling require accurate knowledge of multi-parametric attributes such as the geological, geotechnical, topographic parameters of the study area. The Missouri Rockfall Hazard Rating System (MORH RS) identifies the most potentially problematic areas using digital video logging for the determination of parameters like slope height and angle, face irregularities, etc. This study aims to harvest in a semi-automated approach geometric and qualitative measures through open source platforms that may provide 3-dimensional views of the areas of interest. More specifically, the Street View platform from Google Maps, is hereby used to provide essential information that can be used towards 3-dimensional reconstruction of slopes along highways. The potential of image capturing along a programmable virtual route to provide the input data for photogrammetric processing is also evaluated. Moreover, qualitative characterization of the geological and geotechnical status, based on the Street View images, is performed. These attributes are then integrated to deliver a GIS-based rockfall hazard map. The 3-dimensional models are compared to actual photogrammetric measures in a rockfall prone area in Crete, Greece while in-situ geotechnical characterization is also used to compare and validate the hazard risk. This work is considered as the first step towards the exploitation of open source platforms to improve road safety and the development of an operational system where authorized agencies (i.e., civil protection) will be able to acquire near-real time hazard maps based on video images retrieved either by open source platforms, operational unmanned aerial vehicles, and/or simple video recordings from users. This work has been performed under the framework of the "Cooperation 2011" project ISTRIA (11_SYN_9_13989) funded from the Operational Program "Competitiveness and Entrepreneurship" (co-funded by the European Regional Development Fund (ERDF)) and managed by the Greek General Secretariat for Research and Technology.

Investigation of Finite Sources through Time Reversal

NASA Astrophysics Data System (ADS)

Kremers, Simon; Brietzke, Gilbert; Igel, Heiner; Larmat, Carene; Fichtner, Andreas; Johnson, Paul A.; Huang, Lianjie

2010-05-01

Under certain conditions time reversal is a promising method to determine earthquake source characteristics without any a-priori information (except the earth model and the data). It consists of injecting flipped-in-time records from seismic stations within the model to create an approximate reverse movie of wave propagation from which the location of the hypocenter and other information might be inferred. In this study, the backward propagation is performed numerically using a parallel cartesian spectral element code. Initial tests using point source moment tensors serve as control for the adaptability of the used wave propagation algorithm. After that we investigated the potential of time reversal to recover finite source characteristics (e.g., size of ruptured area, rupture velocity etc.). We used synthetic data from the SPICE kinematic source inversion blind test initiated to investigate the performance of current kinematic source inversion approaches (http://www.spice-rtn.org/library/valid). The synthetic data set attempts to reproduce the 2000 Tottori earthquake with 33 records close to the fault. We discuss the influence of various assumptions made on the source (e.g., origin time, hypocenter, fault location, etc.), adjoint source weighting (e.g., correct for epicentral distance) and structure (uncertainty in the velocity model) on the results of the time reversal process. We give an overview about the quality of focussing of the different wavefield properties (i.e., displacements, strains, rotations, energies). Additionally, the potential to recover source properties of multiple point sources at the same time is discussed.

Sources of fine sediment stored in agricultural lowland streams, Midwest, USA

NASA Astrophysics Data System (ADS)

Lamba, Jasmeet; Thompson, A. M.; Karthikeyan, K. G.; Fitzpatrick, Faith A.

2015-05-01

Agricultural activities can accelerate the offsite transport of productive soil from fields leading to stream water quality degradation. Identification of the nature and relative contribution of different sources to fine-grained sediment (e.g., silts, clays) in streams is important to effectively focus agricultural best management practices in watersheds. Sediment fingerprinting techniques through the use of geochemical tracers are commonly used to differentiate relative contribution from various sources. Research was conducted in lowland streams in the Pleasant Valley watershed in South Central Wisconsin (USA) to identify provenance of fine-grained sediment deposits and evaluate the impact of land use on relative contributions from the following potential sources: cropland, pasture, woodland, and eroding stream banks. Results show that both agriculture (croplands and pastures) and eroding stream banks are primary sources to fine sediment deposits on the stream bed with contributions ranging from 19 to 100% and 0 to 81%, respectively. The increase in area under agricultural land use within a subwatershed results in greater contribution from agriculture (R2 = 0.846, p = 0.0034). Relative contributions from eroding stream banks increased with increasing area under grasslands and woodlands within a subwatershed (R2 = 0.814, p = 0.0055). Subwatersheds with greater mass of fine sediment deposited on the stream bed per unit area should be prioritized for best management practices. The conservation practices should be targeted to stream banks or croplands depending on the dominant source of fine sediment within a subwatershed. Site specific changes in relative contributions from different sources to fine-grained sediment in this watershed highlights the complexities involved in sediment transport dynamics. The nested sampling sites helped determine that sediment dynamics at the subwatershed scale need to be considered for application of targeted conservation techniques.

Sources of fine sediment stored in agricultural lowland streams, Midwest, USA

USGS Publications Warehouse

Lamba, Jasmeet; Thompson, Anita M.; Karthikeyan, K.G.; Fitzpatrick, Faith A.

2015-01-01

Agricultural activities can accelerate the offsite transport of productive soil from fields leading to stream water quality degradation. Identification of the nature and relative contribution of different sources to fine-grained sediment (e.g., silts, clays) in streams is important to effectively focus agricultural best management practices in watersheds. Sediment fingerprinting techniques through the use of geochemical tracers are commonly used to differentiate relative contribution from various sources. Research was conducted in lowland streams in the Pleasant Valley watershed in South Central Wisconsin (USA) to identify provenance of fine-grained sediment deposits and evaluate the impact of land use on relative contributions from the following potential sources: cropland, pasture, woodland, and eroding stream banks. Results show that both agriculture (croplands and pastures) and eroding stream banks are primary sources to fine sediment deposits on the stream bed with contributions ranging from 19 to 100% and 0 to 81%, respectively. The increase in area under agricultural land use within a subwatershed results in greater contribution from agriculture (R2 = 0.846, p = 0.0034). Relative contributions from eroding stream banks increased with increasing area under grasslands and woodlands within a subwatershed (R2 = 0.814, p = 0.0055). Subwatersheds with greater mass of fine sediment deposited on the stream bed per unit area should be prioritized for best management practices. The conservation practices should be targeted to stream banks or croplands depending on the dominant source of fine sediment within a subwatershed. Site specific changes in relative contributions from different sources to fine-grained sediment in this watershed highlights the complexities involved in sediment transport dynamics. The nested sampling sites helped determine that sediment dynamics at the subwatershed scale need to be considered for application of targeted conservation techniques.

Contributions and source identification of biogenic and anthropogenic hydrocarbons to secondary organic aerosols at Mt. Tai in 2014.

PubMed

Zhu, Yanhong; Yang, Lingxiao; Kawamura, Kimitaka; Chen, Jianmin; Ono, Kaori; Wang, Xinfeng; Xue, Likun; Wang, Wenxing

2017-01-01

Ambient fine particulate matter (PM 2.5 ) and volatile organic compounds (VOCs) collected at Mt. Tai in summer 2014 were analysed and the data were used to identify the contribution of biogenic and anthropogenic hydrocarbons to secondary organic aerosols (SOA) and their sources and potential source areas in high mountain regions. Compared with those in 2006, the 2014 anthropogenic SOA tracers in PM 2.5 aerosols and VOC species related to vehicular emissions exhibited higher concentrations, whereas the levels of biogenic SOA tracers were lower, possibly due to decreased biomass burning. Using the SOA tracer and parameterisation method, we estimated the contributions from biogenic and anthropogenic VOCs, respectively. The results showed that the average concentration of biogenic SOA was 1.08 ± 0.51 μg m -3 , among which isoprene SOA tracers were dominant. The anthropogenic VOC-derived SOA were 7.03 ± 1.21 μg m -3 and 1.92 ± 1.34 μg m -3 under low- and high-NO x conditions, respectively, and aromatics made the greatest contribution. However, the sum of biogenic and anthropogenic SOA only contributed 18.1-49.1% of the total SOA. Source apportionment by positive matrix factorisation (PMF) revealed that secondary oxidation and biomass burning were the major sources of biogenic SOA tracers. Anthropogenic aromatics mainly came from solvent use, fuel and plastics combustion and vehicular emissions. However, for > C6 alkanes and cycloalkanes, vehicular emissions and fuel and plastics combustion were the most important contributors. The potential source contribution function (PSCF) identified the Bohai Sea Region (BSR) as the major source area for organic aerosol compounds and VOC species at Mt. Tai. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preview of the BATSE Earth Occultation Catalog of Low Energy Gamma Ray Sources

NASA Technical Reports Server (NTRS)

Harmon, B. A.; Wilson, C. A.; Fishman, G. J.; McCollough, M. L.; Robinson, C. R.; Sahi, M.; Paciesas, W. S.; Zhang, S. N.

1999-01-01

The Burst and Transient Source Experiment (BATSE) aboard the Compton Gamma Ray Observatory (CGRO) has been detecting and monitoring point sources in the high energy sky since 1991. Although BATSE is best known for gamma ray bursts, it also monitors the sky for longer-lived sources of radiation. Using the Earth occultation technique to extract flux information, a catalog is being prepared of about 150 sources potential emission in the large area detectors (20-1000 keV). The catalog will contain light curves, representative spectra, and parametric data for black hole and neutron star binaries, active galaxies, and super-nova remnants. In this preview, we present light curves for persistent and transient sources, and also show examples of what type of information can be obtained from the BATSE Earth occultation database. Options for making the data easily accessible as an "on line" WWW document are being explored.

Effects of changes in pumping on regional groundwater-flow paths, 2005 and 2010, and areas contributing recharge to discharging wells, 1990–2010, in the vicinity of North Penn Area 7 Superfund site, Montgomery County, Pennsylvania

USGS Publications Warehouse

Senior, Lisa A.; Goode, Daniel J.

2017-06-06

A previously developed regional groundwater flow model was used to simulate the effects of changes in pumping rates on groundwater-flow paths and extent of recharge discharging to wells for a contaminated fractured bedrock aquifer in southeastern Pennsylvania. Groundwater in the vicinity of the North Penn Area 7 Superfund site, Montgomery County, Pennsylvania, was found to be contaminated with organic compounds, such as trichloroethylene (TCE), in 1979. At the time contamination was discovered, groundwater from the underlying fractured bedrock (shale) aquifer was the main source of supply for public drinking water and industrial use. As part of technical support to the U.S. Environmental Protection Agency (EPA) during the Remedial Investigation of the North Penn Area 7 Superfund site from 2000 to 2005, the U.S. Geological Survey (USGS) developed a model of regional groundwater flow to describe changes in groundwater flow and contaminant directions as a result of changes in pumping. Subsequently, large decreases in TCE concentrations (as much as 400 micrograms per liter) were measured in groundwater samples collected by the EPA from selected wells in 2010 compared to 2005‒06 concentrations.To provide insight on the fate of potentially contaminated groundwater during the period of generally decreasing pumping rates from 1990 to 2010, steady-state simulations were run using the previously developed groundwater-flow model for two conditions prior to extensive remediation, 1990 and 2000, two conditions subsequent to some remediation 2005 and 2010, and a No Pumping case, representing pre-development or cessation of pumping conditions. The model was used to (1) quantify the amount of recharge, including potentially contaminated recharge from sources near the land surface, that discharged to wells or streams and (2) delineate the areas contributing recharge that discharged to wells or streams for the five conditions.In all simulations, groundwater divides differed from surface-water divides, partly because of differences in stream elevations and because of geologic structure and pumping. In the 1990 and 2000 simulations, all recharge in and near the vicinity of North Penn Area 7 discharged to wells, but in the 2005 and 2010 simulations some recharge in this area discharged to streams, indicating possible discharge of contaminated groundwater from North Penn Area 7 sources to streams. As the amount of groundwater withdrawals by wells has declined since 1990, the area contributing recharge to wells in the vicinity of North Penn Area 7 has decreased.To determine the effect of changes in pumping on flow paths and possible flow-path-related contributions to the observed changes in spatial distribution of contaminants in groundwater from 2005 to 2010, the USGS conducted simulations using the previously developed regional groundwater-flow model using reported pumping and estimated recharge rates for 2005 and 2010. Flow paths from recharge at known contaminant source areas to discharge locations at wells or streams were simulated under steady-state conditions for the two periods. Simulated groundwater-flow paths shifted only slightly from 2005 to 2010 as a result of changes in pumping rates. These slight changes in groundwater-flow paths from known sources of contamination are not coincident with the spatial distribution of observed changes in TCE concentrations from 2005 to 2010, indicating that the decreases of TCE concentrations may be a result of other processes, such as source removal or degradation. Results of the simulations and the absence of increases in TCE-degradation-product concentrations indicate that the decreases of TCE concentrations observed in 2010 may be at least partly related to contaminant-source removal by soil excavation completed in 2005, although additional data would be needed to confirm this preliminary explanation.

Concentrations of polycyclic aromatic hydrocarbons in New York City community garden soils: Potential sources and influential factors.

PubMed

Marquez-Bravo, Lydia G; Briggs, Dean; Shayler, Hannah; McBride, Murray; Lopp, Donna; Stone, Edie; Ferenz, Gretchen; Bogdan, Kenneth G; Mitchell, Rebecca G; Spliethoff, Henry M

2016-02-01

A total of 69 soil samples from 20 community gardens in New York City (New York, USA) were collected and analyzed for 23 polycyclic aromatic hydrocarbons (PAHs) and black carbon. For each garden, samples were collected from nongrowing areas (non-bed) and from vegetable-growing beds, including beds with and without visible sources of PAHs. The sum of the US Environmental Protection Agency's 16 priority PAHs ranged up to 150 mg/kg, and the median (5.4 mg/kg) and mean (14.2 mg/kg) were similar to those previously reported for urban areas in the northeast United States. Isomer ratios indicated that the main sources of PAHs were petroleum, coal, and wood combustion. The PAH concentrations were significantly and positively associated with black carbon and with modeled air PAH concentrations, suggesting a consistent relationship between historical deposition of atmospheric carbon-adsorbed PAHs and current PAH soil concentrations. Median PAH soil concentration from non-bed areas was higher (7.4 mg/kg) than median concentration from beds in the same garden (4.0 mg/kg), and significantly higher than the median from beds without visible sources of PAHs (3.5 mg/kg). Median PAH concentration in beds from gardens with records of soil amendments was 58% lower compared with beds from gardens without those records. These results suggest that gardening practices in garden beds without visible sources of PAHs contribute to reduce PAH soil concentrations. © 2015 SETAC.

Hydrogeology for land-use planning: the Peters Creek area, Municipality of Anchorage, Alaska

USGS Publications Warehouse

Brunett, Jilann O.; Lee, Michael

1983-01-01

Wells currently provide all water supplies in the area. Most wells obtain enough water for individual household needs from unconsolidated, principally glacial and glacioalluvial deposits. In some places, however, wells must be drilled into the underlying bedrock to obtain adequate supplies. It may be possible to develop small community supplies--for individual trailer courts or subdivisions--in areas where yields of 20 gallons per minute or greater are reported for private, domestic wells. Peters Creek is a potential source of surface-water supply, but it would have to be treated to remove glacial silt during summer months. The chemical quality of both ground water and surface water in the area in generally acceptable for most uses. Foundation and excavation conditions, the potential for water pollution from onsite disposal of wastewater through septic tank systems, and the suitability of specific areas for certain types of development may be affected by the following factors: wetlands and areas of shallow ground water underlie about 30 percent of the study area; landslope exceeds 20 percent in about a third of the area; areas of fine-grained, low-permeability sediments are present locally; bedrock is within 25 feet of the land surface in about a third of the area. (USGS)

Elevated blood-lead levels among children living in the rural Philippines.

PubMed

Riddell, Travis J; Solon, Orville; Quimbo, Stella A; Tan, Cheryl May C; Butrick, Elizabeth; Peabody, John W

2007-09-01

Generally, lead poisoning is not considered a significant environmental hazard for children in rural areas of developing countries. With a prospectively designed policy experiment, the research community and the government are conducting a broad-based investigation to introduce and evaluate the impact of health policy reforms on children in a rural area of the Philippines - the Quality Improvement Demonstration Study (QIDS). As part of this study, we researched lead exposure in children under the age of five. We sampled a population of children from the Visayas region in the central Philippines, covering approximately one third of the country's geographical area. From December 2003 to September 2004, the survey collected blood lead levels (BLL) together with demographic, socioeconomic and child health data points. Supplemental field-testing among a sub-sample of the most exposed children assessed the sources of environmental lead exposure. Among children in this study, 21% (601 of 2861 children) had BLL greater than 10 microg/dl. BLL were associated independently with age, haemoglobin concentration, water source, roofing material, expenditures and history of breastfeeding. A follow-up assessment of possible environmental exposures among the sub-sample of children with elevated BLL revealed no single or predominant exposure source. Instead, there appear to be multiple potential sources, such as fossil-fuel combustion, lead paint (in or around 38% of homes) and household items. Elevated BLL are common among children in the Visayas, and may signify an under-recognized threat to children living in rural areas of other developing nations. This setting has varied environmental sources of lead. Observed correlates of BLL may be of clinical, environmental and public health utility to identify and mitigate the consequences of lead toxicity.

Risk assessment of debris flow hazards in natural slope

NASA Astrophysics Data System (ADS)

Choi, Junghae; Chae, Byung-gon; Liu, Kofei; Wu, Yinghsin

2016-04-01

The study area is located at north-east part of South Korea. Referring to the map of landslide sus-ceptibility (KIGAM, 2009) from Korea Institute of Geoscience and Mineral Resources (KIGAM for short), there are large areas of potential landslide in high probability on slope land of mountain near the study area. Besides, recently some severe landslide-induced debris flow hazards occurred in this area. So this site is convinced to be prone to debris flow haz-ards. In order to mitigate the influence of hazards, the assessment of potential debris flow hazards is very important and essential. In this assessment, we use Debris-2D, debris flow numerical program, to assess the potential debris flow hazards. The worst scenario is considered for simulation. The input mass sources are determined using landslide susceptibility map. The water input is referred to the daily accumulative rainfall in the past debris flow event in study area. The only one input material property, i.e. yield stress, is obtained using calibration test. The simulation results show that the study area has po-tential to be impacted by debris flow. Therefore, based on simulation results, to mitigate debris flow hazards, we can propose countermeasures, including building check dams, constructing a protection wall in study area, and installing instruments for active monitoring of debris flow hazards. Acknowledgements:This research was supported by the Public Welfare & Safety Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT & Future Planning (NRF-2012M3A2A1050983)

Status and understanding of groundwater quality in the Cascade Range and Modoc Plateau study unit, 2010: California GAMA Priority Basin Project

USGS Publications Warehouse

Fram, Miranda S.; Shelton, Jennifer L.

2015-01-01

Organic constituents were not detected at high or moderate RCs, and the occurrence of low organic constituents at low RCs ranged from 27 percent to 73 percent of the primary aquifers system in the six study areas. The Shasta Valley and Mount Shasta Volcanic study area had significantly greater occurrence of low RCs of herbicides compared to all of the other study areas, which could reflect the greater prevalence of modern groundwater in the Shasta Valley and Mount Shasta Volcanic study area and the presence of potential sources of herbicides, including applications to timberlands and roadside rights-of-way. The Eastside Sacramento Valley study area had the greatest occurrence of low concentrations of chloroform, and chloroform occurrence was most strongly associated with the combination of septic-tank density greater than two tanks per square kilometer and urban land use greater than 10 percent within a radius of 500 meters of the well. These conditions were most prevalent in the Eastside Sacramento Valley study area. The detection frequency of low concentrations of perchlorate was consistent with the probability of occurrence expected under natural conditions, except in the Eastside Sacramento Valley study area, where detection frequencies were much higher than expected and could not be explained by known anthropogenic sources of perchlorate.

Contamination characteristics, ecological risk and source identification of trace metals in sediments of the Le'an River (China).

PubMed

Chen, Haiyang; Chen, Ruihui; Teng, Yanguo; Wu, Jin

2016-03-01

Recognizing the pollution characteristics of trace metals in river sediments and targeting their potential sources are of key importance for proposing effective strategies to protect watershed ecosystem health. In this study, a comprehensive investigation was conducted to identify the contamination and risk characteristics of trace metals in sediments of Le'an River which is a main tributary of the largest freshwater lake in China, Poyang Lake. To attain this objective, several tools and models were considered. Geoaccumulation index and enrichment factor were used to understand the general pollution characteristic of trace metals in sediments. Discriminant analysis was applied to identify the spatial variability of sediment metals. Sediment quality guidelines and potential ecological risk index were employed for ecological risk evaluation. Multivariate curve resolution-alternating least square was proposed to extract potential pollution sources, as well as the application of Monte-Carlo simulation for uncertainty analysis of source identification. Results suggested that the sediments in Le'an River were considerably polluted by the investigated trace metals (Cd, Cr, As, Hg, Pb, Cu, Zn and Ni). Sediment concentrations of these metals showed significant spatial variations. The potential ecological risk lay in high level. Comparatively speaking, the metals of Cd, Cu and Hg were likely to result in more harmful effects. Mining activities and the application of fertilizers and agrochemicals were identified as the main anthropogenic sources. To protect the ecological system of Le'an River and Poyang Lake watershed, industrial mining and agricultural activities in this area should to be strictly regulated. Copyright © 2015 Elsevier Inc. All rights reserved.

Preliminary source rock evaluation and hydrocarbon generation potential of the early Cretaceous subsurface shales from Shabwah sub-basin in the Sabatayn Basin, Western Yemen

NASA Astrophysics Data System (ADS)

Al-Matary, Adel M.; Hakimi, Mohammed Hail; Al Sofi, Sadam; Al-Nehmi, Yousif A.; Al-haj, Mohammed Ail; Al-Hmdani, Yousif A.; Al-Sarhi, Ahmed A.

2018-06-01

A conventional organic geochemical study has been performed on the shale samples collected from the early Cretaceous Saar Formation from the Shabwah oilfields in the Sabatayn Basin, Western Yemen. The results of this study were used to preliminary evaluate the potential source-rock of the shales in the Saar Formation. Organic matter richness, type, and petroleum generation potential of the analysed shales were assessed. Total organic carbon content and Rock- Eval pyrolysis results indicate that the shale intervals within the early Cretaceous Saar Formation have a wide variation in source rock generative potential and quality. The analysed shale samples have TOC content in the range of 0.50 and 5.12 wt% and generally can be considered as fair to good source rocks. The geochemical results of this study also indicate that the analysed shales in the Saar Formation are both oil- and gas-prone source rocks, containing Type II kerogen and mixed Types II-III gradient to Type III kerogen. This is consistent with Hydrogen Index (HI) values between 66 and 552 mg HC/g TOC. The temperature-sensitive parameters such as vitrinite reflectance (%VRo), Rock-Eval pyrolysis Tmax and PI reveal that the analysed shale samples are generally immature to early-mature for oil-window. Therefore, the organic matter has not been altered by thermal maturity thus petroleum has not yet generated. Therefore, exploration strategies should focus on the known deeper location of the Saar Formation in the Shabwah-sub-basin for predicting the kitchen area.

Texture and composition of the Rosa Marina beach sands (Adriatic coast, southern Italy): a sedimentological/ecological approach

NASA Astrophysics Data System (ADS)

Moretti, Massimo; Tropeano, Marcello; Loon, A. J. (Tom) van; Acquafredda, Pasquale; Baldacconi, Rossella; Festa, Vincenzo; Lisco, Stefania; Mastronuzzi, Giuseppe; Moretti, Vincenzo; Scotti, Rosa

2016-06-01

Beach sands from the Rosa Marina locality (Adriatic coast, southern Italy) were analysed mainly microscopically in order to trace the source areas of their lithoclastic and bioclastic components. The main cropping out sedimentary units were also studied with the objective to identify the potential source areas of lithoclasts. This allowed to establish how the various rock units contribute to the formation of beach sands. The analysis of the bioclastic components allows to estimate the actual role of organisms regarding the supply of this material to the beach. Identification of taxa that are present in the beach sands as shell fragments or other remains was carried out at the genus or family level. Ecological investigation of the same beach and the recognition of sub-environments (mainly distinguished on the basis of the nature of the substrate and of the water depth) was the key topic that allowed to establish the actual source areas of bioclasts in the Rosa Marina beach sands. The sedimentological analysis (including a physical study of the beach and the calculation of some statistical parameters concerning the grain-size curves) shows that the Rosa Marina beach is nowadays subject to erosion.

Status, sources, and human health risk assessment of PAHs via foliar dust from different functional areas in Nanjing, China.

PubMed

Zha, Yan; Zhang, Yin L; Tang, Jie; Sun, Kai

2018-05-12

The present study was carried out to assess and understand the potential health risk, level of contamination, composition pattern, and sources of urban foliar dust in Nanjing City with respect to polycyclic aromatic hydrocarbons (PAHs). Five urban functional areas of foliar dust were analysed and the contents of 16 priority PAHs were determined. Total PAH concentrations in foliar dust ranged from 1.77 to 19.02 μg·g -1 , with an average value of 6.98 μg·g -1 . The PAH pattern was dominated by four and five-ring PAHs (contributing > 38% of total PAHs) in all of the five functional areas. The results indicated that the combustion of fossil fuel, coal, and biomass, as well as vehicle traffic emissions were the major sources of PAHs. The estimated incremental lifetime cancer risk due to PAHs in foliar dust were 8.19 × 10 -6 , 6.63 × 10 -6 , and 9.65 × 10 -6 for childhood, adolescence and adulthood, respectively, indicating a high risk of cancer from exposure to foliar dust in Nanjing. Our results indicated that foliar dust might be a useful indicator of atmospheric PAH pollution.

The use of mud as an alternative source for bioelectricity using microbial fuel cells

NASA Astrophysics Data System (ADS)

Darmawan, Raden; Widjaja, Arief; Juliastuti, Sri Rachmania; Hendrianie, Nuniek; Hidaya, Chanifah; Sari, Dessy Rosita; Suwito, Morimura, Shigeru; Tominaga, Masato

2017-05-01

Alternative energy sources to substitute fossil-based energy is expected, as the fossil energy reserves decreasing every day. Mud is considered to be economical as the material sources for generating the electricity where it could be found easily and abundantly in Indonesia. The existence of a lot of mud that contains organic material has great potential as a source of electrical energy using microbial fuel cells (MFCs). It provides a promising technology by degrading organic compounds to yield the sustainable energy. The different sampling sites were determined to find out the electricity production, i.e. mud from soil water, brackish water and sea water using an anode immersed of 10 cm2. The results suggest that the electricity generation of the three areas are 0.331, 0.327 and 0.398 V (in terms of voltage); 0.221, 0.050 and 0.325 mA (in terms of electric current), respectively. It is investigated that the mud obtained the sea water exhibits the highest power potential compared to that obtained from the brackish and soil water.

Assessment of polycyclic aromatic hydrocarbons (PAHs) contamination in surface soil of coal stockpile sites in South Kalimantan, Indonesia.

PubMed

Mizwar, Andy; Priatmadi, Bambang Joko; Abdi, Chairul; Trihadiningrum, Yulinah

2016-03-01

Concentrations, spatial distribution, and sources of 16 polycyclic aromatic hydrocarbons (PAHs), listed as priority pollutants by the United States Environmental Protection Agency (USEPA), were investigated in surface soils of three different coal stockpile, agricultural, and residential sites in South Kalimantan Province, Indonesia. Total PAHs concentration ranged from 4.69 to 22.67 mg kg(-1)-dw. PAHs concentrations in soil of coal stockpile sites were higher than those in agricultural and residential soil. A complex of petrogenic origin and pyrolytic sources was found within the study area, as suggested by the isomeric ratios of PAHs. The results of principal component analysis and multiple linear regressions (PCA/MLR) showed that three sources contributed to the PAHs in the study area, including biomass and coal combustion (48.46%), raw coal (35.49%), and vehicular emission (16.05%). The high value of total benzo[a]pyrene equivalent concentration (B[a]Peq) suggests that local residents are exposed to a high carcinogenic potential.

Small lasers in flow cytometry.

PubMed

Telford, William G

2004-01-01

Laser technology has made tremendous advances in recent years, particularly in the area of diode and diode-pumped solid state sources. Flow cytometry has been a direct beneficiary of these advances, as these small, low-maintenance, inexpensive lasers with reasonable power outputs are integrated into flow cytometers. In this chapter we review the contribution and potential of solid-state lasers to flow cytometry, and show several examples of these novel sources integrated into production flow cytometers. Technical details and critical parameters for successful application of these lasers for biomedical analysis are reviewed.

Predators

USGS Publications Warehouse

Young, Donald D.; McCabe, Thomas R.; Ambrose, Robert E.; Garner, Gerald W.; Weiler, Greg J.; Reynolds, Harry V.; Udevitz, Mark S.; Reed, Dan J.; Griffith, Brad; Douglas, David C.; Reynolds, Patricia E.; Rhode, E.B.

2002-01-01

Calving caribou (Rangifer tarandus) of the Central Arctic herd, Alaska, have avoided the infrastructure associated with the complex of petroleum development areas from Prudhoe Bay to Kuparuk (Cameron et al. 1992, Nellemann and Cameron 1998, and Section 4 of this document). Calving females of the Porcupine caribou herd may similarly avoid any oil field roads and pipelines developed in areas traditionally used during the calving and post-calving periods. This may displace the caribou females and calves to areas east and south of the 1002 Area of the Arctic National Wildlife Refuge.Increased calf mortality could occur if calving caribou are displaced into areas that have a higher density of predators, higher rates of predation, or where a higher proportion of the predators regularly use caribou as a food source (Whitten et al. 1992).Our study assessed predation risks to caribou calving in the 1002 Area versus calving in potential displacement areas. Due to funding constraints, our research focused on grizzly bears (Ursus arctos), with wolves (Camus lupus) and golden eagles (Aquila chrysaetos) receiving only cursory attention. Our research objectives were 1) to compare relative abundance of predators within the 1002 Area with that in adjacent peripheral areas, 2) to determine factors affecting predator abundance on the calving grounds, and 3) to quantify the use of caribou as a food source for predators and the importance of caribou to the productivity of predator populations using the coastal plain of the Arctic National Wildlife Refuge.

Nitrate contamination risk assessment in groundwater at regional scale

NASA Astrophysics Data System (ADS)

Daniela, Ducci

2016-04-01

Nitrate groundwater contamination is widespread in the world, due to the intensive use of fertilizers, to the leaking from the sewage network and to the presence of old septic systems. This research presents a methodology for groundwater contamination risk assessment using thematic maps derived mainly from the land-use map and from statistical data available at the national institutes of statistic (especially demographic and environmental data). The potential nitrate contamination is considered as deriving from three sources: agricultural, urban and periurban. The first one is related to the use of fertilizers. For this reason the land-use map is re-classified on the basis of the crop requirements in terms of fertilizers. The urban source is the possibility of leaks from the sewage network and, consequently, is linked to the anthropogenic pressure, expressed by the population density, weighted on the basis of the mapped urbanized areas of the municipality. The periurban sources include the un-sewered areas, especially present in the periurban context, where illegal sewage connections coexist with on-site sewage disposal (cesspools, septic tanks and pit latrines). The potential nitrate contamination map is produced by overlaying the agricultural, urban and periurban maps. The map combination process is very easy, being an algebraic combination: the output values are the arithmetic average of the input values. The groundwater vulnerability to contamination can be assessed using parametric methods, like DRASTIC or easier, like AVI (that involves a limited numbers of parameters). In most of cases, previous documents produced at regional level can be used. The pollution risk map is obtained by combining the thematic maps of the potential nitrate contamination map and the groundwater contamination vulnerability map. The criterion for the linkages of the different GIS layers is very easy, corresponding to an algebraic combination. The methodology has been successfully applied in a large flat area of southern Italy, with high concentrations in NO3.

Tiny is mighty: seagrass beds have a large role in the export of organic material in the tropical coastal zone.

PubMed

Gillis, Lucy G; Ziegler, Alan D; van Oevelen, Dick; Cathalot, Cecile; Herman, Peter M J; Wolters, Jan W; Bouma, Tjeerd J

2014-01-01

Ecosystems in the tropical coastal zone exchange particulate organic matter (POM) with adjacent systems, but differences in this function among ecosystems remain poorly quantified. Seagrass beds are often a relatively small section of this coastal zone, but have a potentially much larger ecological influence than suggested by their surface area. Using stable isotopes as tracers of oceanic, terrestrial, mangrove and seagrass sources, we investigated the origin of particulate organic matter in nine mangrove bays around the island of Phuket (Thailand). We used a linear mixing model based on bulk organic carbon, total nitrogen and δ13C and δ15N and found that oceanic sources dominated suspended particulate organic matter samples along the mangrove-seagrass-ocean gradient. Sediment trap samples showed contributions from four sources oceanic, mangrove forest/terrestrial and seagrass beds where oceanic had the strongest contribution and seagrass beds the smallest. Based on ecosystem area, however, the contribution of suspended particulate organic matter derived from seagrass beds was disproportionally high, relative to the entire area occupied by mangrove forests, the catchment area (terrestrial) and seagrass beds. The contribution from mangrove forests was approximately equal to their surface area, whereas terrestrial contributions to suspended organic matter under contributed compared to their relative catchment area. Interestingly, mangrove forest contribution at 0 m on the transects showed a positive relationship with the exposed frontal width of the mangrove, indicating that mangrove forest exposure to hydrodynamic energy may be a controlling factor in mangrove outwelling. However we found no relationship between seagrass bed contribution and any physical factors, which we measured. Our results indicate that although seagrass beds occupy a relatively small area of the coastal zone, their role in the export of organic matter is disproportional and should be considered in coastal management especially with respect to their importance as a nutrient source for other ecosystems and organisms.

INEEL Subregional Conceptual Model Report Volume 3: Summary of Existing Knowledge of Natural and Anthropogenic Influences on the Release of Contaminants to the Subsurface Environment from Waste Source Terms at the INEEL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paul L. Wichlacz

2003-09-01

This source-term summary document is intended to describe the current understanding of contaminant source terms and the conceptual model for potential source-term release to the environment at the Idaho National Engineering and Environmental Laboratory (INEEL), as presented in published INEEL reports. The document presents a generalized conceptual model of the sources of contamination and describes the general categories of source terms, primary waste forms, and factors that affect the release of contaminants from the waste form into the vadose zone and Snake River Plain Aquifer. Where the information has previously been published and is readily available, summaries of the inventorymore » of contaminants are also included. Uncertainties that affect the estimation of the source term release are also discussed where they have been identified by the Source Term Technical Advisory Group. Areas in which additional information are needed (i.e., research needs) are also identified.« less

Photochemical Grid Modelling Study to Assess Potential Air Quality Impacts Associated with Energy Development in Colorado and Northern New Mexico.

NASA Astrophysics Data System (ADS)

Parker, L. K.; Morris, R. E.; Zapert, J.; Cook, F.; Koo, B.; Rasmussen, D.; Jung, J.; Grant, J.; Johnson, J.; Shah, T.; Pavlovic, T.

2015-12-01

The Colorado Air Resource Management Modeling Study (CARMMS) was funded by the Bureau of Land Management (BLM) to predict the impacts from future federal and non-federal energy development in Colorado and Northern New Mexico. The study used the Comprehensive Air Quality Model with extensions (CAMx) photochemical grid model (PGM) to quantify potential impacts from energy development from BLM field office planning areas. CAMx source apportionment technology was used to track the impacts from multiple (14) different emissions source regions (i.e. field office areas) within one simulation, as well as to assess the cumulative impact of emissions from all source regions combined. The energy development emissions estimates were for the year 2021 for three different development scenarios: (1) low; (2) high; (3) high with emissions mitigation. Impacts on air quality (AQ) including ozone, PM2.5, PM10, NO2, SO2, and air quality related values (AQRVs) such as atmospheric deposition, regional haze and changes in Acid Neutralizing Capacity (ANC) of lakes were quantified, and compared to establish threshold levels. In this presentation, we present a brief summary of the how the emission scenarios were developed, we compare the emission totals for each scenario, and then focus on the ozone impacts for each scenario to assess: (1). the difference in potential ozone impacts under the different development scenarios and (2). to establish the sensitivity of the ozone impacts to different emissions levels. Region-wide ozone impacts will be presented as well as impacts at specific locations with ozone monitors.

Summary of regional geology, petroleum potential, resource assessment and environmental considerations for oil and gas lease sale area No. 56

USGS Publications Warehouse

Dillon, William P.; Klitgord, Kim D.; Paull, Charles K.; Grow, John A.; Ball, Mahlon M.; Dolton, Gordon L.; Powers, Richard B.; Khan, Abdul S.; Popenoe, Peter; Robb, James M.; Dillon, William P.

1980-01-01

This report summarizes our general knowledge of the petroleum potential, as well as problems and hazards associated with development of petroleum resources in the area proposed for nominations for lease sale number 56. This area includes the U.S. eastern continental margin from the North Carolina-Virginia border south to approximately Cape Canaveral, Florida and from three miles from shore, seaward to include the upper Continental Slope and inner Blake Plateau. The area for possible sales is shown in figure 1; major physiographic features of the region are shown in figure 2.No wells have been drilled for petroleum within this proposed lease area and no significant commercial production has been obtained onshore in the Southeast Georgia Embayment. The COST GE-1 stratigraphic test well, drilled on the Continental Shelf off Jacksonville, Fla. (fig- 1), reached basement at 3,300 m. The bottom third of the section consists of dominantly continental rocks that are typically poor sources of petroleum (Scholle, 1979) and the rocks that contain organic carbon adequate for generation of petroleum at the well are seen in seismic profiles always at shallow subbottom depths, so they probably have not reached thermal maturity. However, seismic profiles indicate that the sedimentary deposits thicken markedly in a seaward direction where more of the section was deposited under marine conditions; therefore, commercial accumulations of petroleum offshore are more likely.Several potential sources of environmental hazard exist. Among the most important are hurricanes, the Gulf Stream, and earthquakes. The potential danger from high wind, waves, storm surges, and storm-driven currents associated with hurricanes is obvious. Evidence for significant bottom scour by the Gulf Stream is abundant; such scour is a threat to the stability of bottom-mounted structures. The fast-flowing water also will hamper floating drill rigs and control of drill strings. A major earthquake of about magnitude 6.8 struck Charleston in 1886; it may have been associated with a zone of active seismicity that crosses South Carolina. The likelihood of a repetition of the 1886 event is presently not predictable but a seismic hazard must be assumed to exist.

Identification and Classification of Mass Transport Complexes in Offshore Trinidad/Venezuela and Their Potential Anthropogenic Impact as Tsunamigenic Hazards

NASA Astrophysics Data System (ADS)

Moscardelli, L.; Wood, L. J.

2006-12-01

Several late Pleistocene-age seafloor destabilization events have been identified in the continental margin of eastern offshore Trinidad, of sufficient scale to produce tsunamigenic forces. This area, situated along the obliquely-converging-boundary of the Caribbean/South American plates and proximal to the Orinoco Delta, is characterized by catastrophic shelf-margin processes, intrusive-extrusive mobile shales, and active tectonism. A mega-merged, 10,000km2, 3D seismic survey reveals several mass transport complexes that range in area from 11.3km2 to 2017km2. Historical records indicate that this region has experienced submarine landslide- generated tsunamigenic events, including tsunamis that affected Venezuela during the 1700's-1900's. This work concentrates on defining those ancient deep marine mass transport complexes whose occurrence could potentially triggered tsunamis. Three types of failures are identified; 1) source-attached failures that are fed by shelf edge deltas whose sediment input is controlled by sea-level fluctuations and sedimentation rates, 2) source-detached systems, which occur when upper slope sediments catastrophically fail due to gas hydrate disruptions and/or earthquakes, and 3) locally sourced failures, formed when local instabilities in the sea floor trigger relatively smaller collapses. Such classification of the relationship between slope mass failures and the sourcing regions enables a better understanding of the nature of initiation, length of development history and petrography of such mass transport deposits. Source-detached systems, generated due to sudden sediment remobilizations, are more likely to disrupt the overlying water column causing a rise in tsunamigenic risk. Unlike 2D seismic, 3D seismic enables scientists to calculate more accurate deposit volumes, improve deposit imaging and thus increase the accuracy of physical and computer simulations of mass failure processes.

Emissions of CO2 and criteria air pollutants from mobile sources: Insights from integrating real-time traffic data into local air quality models

NASA Astrophysics Data System (ADS)

Gately, Conor; Hutyra, Lucy

2016-04-01

In 2013, on-road mobile sources were responsible for over 26% of U.S. fossil fuel carbon dioxide (ffCO2) emissions, and over 34% of both CO and NOx emissions. However, accurate representations of these emissions at the scale of urban areas remains a difficult challenge. Quantifying emissions at the scale of local streets and highways is critical to provide policymakers with the information needed to develop appropriate mitigation strategies and to guide research into the underlying process that drive mobile emissions. Quantification of vehicle ffCO2 emissions at high spatial and temporal resolutions requires a detailed synthesis of data on traffic activity, roadway attributes, fleet characteristics and vehicle speeds. To accurately characterize criteria air pollutant emissions, information on local meteorology is also critical, as the temperature and relative humidity can affect emissions rates of these pollutants by as much as 400%. As the health impacts of air pollutants are more severe for residents living in close proximity (<500m) to road sources, it is critical that inventories of these emissions rely on highly resolved source data to locate potential hot-spots of exposure. In this study we utilize real-time GPS estimates of vehicle speeds to estimate ffCO2 and criteria air pollutant emissions at multiple spatial and temporal scales across a large metropolitan area. We observe large variations in emissions associated with diurnal activity patterns, congestion, sporting and civic events, and weather anomalies. We discuss the advantages and challenges of using highly-resolved source data to quantify emissions at a roadway scale, and the potential of this methodology for forecasting the air quality impacts of changes in infrastructure, urban planning policies, and regional climate.

Emissions of CO2 and criteria air pollutants from mobile sources: Insights from integrating real-time traffic data into local air quality models

NASA Astrophysics Data System (ADS)

Gately, C.; Hutyra, L.; Sue Wing, I.; Peterson, S.; Janetos, A.

2015-12-01

In 2013, on-road mobile sources were responsible for over 26% of U.S. fossil fuel carbon dioxide (ffCO2) emissions, and over 34% of both CO and NOx emissions. However, accurate representations of these emissions at the scale of urban areas remains a difficult challenge. Quantifying emissions at the scale of local streets and highways is critical to provide policymakers with the information needed to develop appropriate mitigation strategies and to guide research into the underlying process that drive mobile emissions. Quantification of vehicle ffCO2 emissions at high spatial and temporal resolutions requires a detailed synthesis of data on traffic activity, roadway attributes, fleet characteristics and vehicle speeds. To accurately characterize criteria air pollutant emissions, information on local meteorology is also critical, as the temperature and relative humidity can affect emissions rates of these pollutants by as much as 400%. As the health impacts of air pollutants are more severe for residents living in close proximity (<500m) to road sources, it is critical that inventories of these emissions rely on highly resolved source data to locate potential hot-spots of exposure. In this study we utilize real-time GPS estimates of vehicle speeds to estimate ffCO2 and criteria air pollutant emissions at multiple spatial and temporal scales across a large metropolitan area. We observe large variations in emissions associated with diurnal activity patterns, congestion, sporting and civic events, and weather anomalies. We discuss the advantages and challenges of using highly-resolved source data to quantify emissions at a roadway scale, and the potential of this methodology for forecasting the air quality impacts of changes in infrastructure, urban planning policies, and regional climate.

Potentially Prebiotic Syntheses of Condensed Phosphates

NASA Technical Reports Server (NTRS)

Keefe, Anthony D.; Miller, Stanley L.

1996-01-01

In view of the importance of a prebiotic source of high energy phosphates, we have investigated a number of potentially prebiotic processes to produce condensed phosphates from orthophosphate and cyclic trimetaphosphate from tripolyphosphate. The reagents investigated include polymerizing nitriles, acid anhydrides, lactones, hexamethylene tetramine and carbon suboxide. A number of these processes give substantial yields of pyrophosphate from orthophosphate and trimetaphosphate from tripolyphosphate. Although these reactions may have been applicable in local areas, they are not sufficiently robust to have been of importance in the prebiotic open ocean.

DOE Office of Scientific and Technical Information (OSTI.GOV)

LaFreniere, L. M.; Environmental Science Division

The 2007 investigation of carbon tetrachloride and chloroform contamination at Powhattan, Kansas, was conducted at the request of the Kansas Department of Health and Environment (KDHE 2006a). The Environmental Science Division of Argonne National Laboratory implemented the investigation on behalf of the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA). The primary purposes of the investigation were to evaluate potential contaminant source areas on the former CCC/USDA property, determine the horizontal and vertical extent of potential contamination, conduct groundwater monitoring, and provide recommendations for future action.

Scientific Evidence and Potential Barriers in the Management of Brazilian Protected Areas.

PubMed

Giehl, Eduardo L H; Moretti, Marcela; Walsh, Jessica C; Batalha, Marco A; Cook, Carly N

2017-01-01

Protected areas are a crucial tool for halting the loss of biodiversity. Yet, the management of protected areas is under resourced, impacting the ability to achieve effective conservation actions. Effective management depends on the application of the best available knowledge, which can include both scientific evidence and the local knowledge of onsite managers. Despite the clear value of evidence-based conservation, there is still little known about how much scientific evidence is used to guide the management of protected areas. This knowledge gap is especially evident in developing countries, where resource limitations and language barriers may create additional challenges for the use of scientific evidence in management. To assess the extent to which scientific evidence is used to inform management decisions in a developing country, we surveyed Brazilian protected area managers about the information they use to support their management decisions. We targeted on-ground managers who are responsible for management decisions made at the local protected area level. We asked managers about the sources of evidence they use, how frequently they assess the different sources of evidence and the scientific content of the different sources of evidence. We also considered a range of factors that might explain the use of scientific evidence to guide the management of protected areas, such as the language spoken by managers, the accessibility of evidence sources and the characteristics of the managers and the protected areas they manage. The managers who responded to our questionnaire reported that they most frequently made decisions based on their personal experience, with scientific evidence being used relatively infrequently. While managers in our study tended to value scientific evidence less highly than other sources, most managers still considered science important for management decisions. Managers reported that the accessibility of scientific evidence is low relative to other types of evidence, with key barriers being the low levels of open access research and insufficient technical training to enable managers to interpret research findings. Based on our results, we suggest that managers in developing countries face all the same challenges as those in developed countries, along with additional language barriers that can prevent greater use of scientific evidence to support effective management of protected areas in Brazil.

Chemical and biological tracers to determine groundwater flow in karstic aquifer, Yucatan Peninsula

NASA Astrophysics Data System (ADS)

Lenczewski, M.; Leal-Bautista, R. M.; McLain, J. E.

2013-05-01

Little is known about the extent of pollution in groundwater in the Yucatan Peninsula; however current population growth, both from international tourism and Mexican nationals increases the potential for wastewater release of a vast array of contaminants including personal care products, pharmaceuticals (Rx), and pathogenic microorganisms. Pathogens and Rx in groundwater can persist and can be particularly acute in this region where high permeability of the karst bedrock and the lack of top soil permit the rapid transport of contaminants into groundwater aquifers. The objective of this research is to develop and utilize novel biological and chemical source tracking methods to distinguish between different sources of anthropogenic pollution in degraded groundwater. Although several methods have been used successfully to track fecal contamination sources in small scale studies, little is known about their spatial limitations, as source tracking studies rarely include sample collection over a wide geographical area and with different sources of water. In addition, although source tracking methods to distinguish human from animal fecal contamination are widely available, this work has developed source tracking distinguish between separate human populations is highly unique. To achieve this objective, we collected water samples from a series of drinking wells, cenotes (sinkholes), wastewater treatment plants, and injection wells across the Yucatan Peninsula and examine potential source tracers within the collected water samples. The result suggests that groundwater sources impacted by tourist vs. local populations contain different chemical stressors. This work has developed a more detailed understanding of the presence and persistence of personal care products, pharmaceuticals, and fecal indicators in a karstic system; such understanding will be a vital component for the protection Mexican groundwater and human health. Quantification of different pollution sources within groundwater samples identified point sources of pollution, identify potential remediation strategies, and contribute to an improved understanding of the environmental impact of tourism and tourism-generated waste products on this groundwater-dependent ecosystem.

Topographic map analysis to determine Arjuno-Welirang volcanostratigraphy and implication for geothermal exploration

NASA Astrophysics Data System (ADS)

Apriani, Lestari; Satriana, Joshua; Aulian Chalik, Citra; Syahputra Mulyana, Reza; Hafidz, Muhammad; Suryantini

2017-12-01

Volcanostratigraphy study is used for supporting geothermal exploration on preliminary survey. This study is important to identify volcanic eruption center which shows potential area of geothermal heat source. The purpose of volcanostratigraphy study in research area is going to distinguish the characteristics of volcanic eruption product that construct the volcanic body. The analysis of Arjuno-Welirang volcanostratigraphy identification are based on topographic maps of Malang sheet with 1:100.000 scale, 1:50.000 scale, and a geological map. Regarding to the delineation of ridge and river, we determine five crowns, three hummocks, one brigade and one super brigade. The crowns consist of Ringgit, Welirang, Arjuno, Kawi, and Penanggungan, the hummocks comprise of Kembar III, Kembar II, and Kembar I, the brigade is Arjuno-Welirang, and the super brigade is Tengger. Based on topographic map interpretation and geothermal prospect evaluation method analysis, shows that Arjuno-Welirang prospect area have good geothermal resource potential.

Superfund record of decision (EPA Region 9): Aircraft Control and Warning Site, Mather Air Force Base, CA, December 1993

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This decision document, a Record of Decision (ROD), presents the selected remedial action for the AC W Site, Installation Restoration Program (IRP) Site 12, at Mather Air Force Base (AFB), Sacramento County, California. Reports indicate that from 1958 to 1966 waste solvents and transformer oils were disposed in a waste disposal pipe in the AC W area. Investigations conducted as part of the Air Force Installation Restoration Program (IRP) failed to locate the waste disposal pipe but did find trichloroethylene (TCE) contamination in the shallow water bearing zone (SWBZ) in the AC W area. The SWBZ is classified as amore » potential source of drinking water by the State of California, although it is not currently used in the AC W area. The selected remedy will address the potential threat to human health posed by TCE contamination in groundwater (primarily in the SWBZ).« less

Estimating harvested rainwater at greenhouses in south Portugal aquifer Campina de Faro for potential infiltration in Managed Aquifer Recharge.

NASA Astrophysics Data System (ADS)

Costa, Luís; Monteiro, José Paulo; Leitão, Teresa; Lobo-Ferreira, João Paulo; Oliveira, Manuel; Martins de Carvalho, José; Martins de Carvalho, Tiago; Agostinho, Rui

2015-04-01

The Campina de Faro (CF) aquifer system, located on the south coast of Portugal, is an important source of groundwater, mostly used for agriculture purposes. In some areas, this multi-layered aquifer is contaminated with high concentration of nitrates, possibly arising from excessive usage of fertilizers, reaching to values as high as 300 mg/L. In order to tackle this problem, Managed Aquifer Recharge (MAR) techniques are being applied at demonstration scale to improve groundwater quality through aquifer recharge, in both infiltration basins at the river bed of ephemeral river Rio Seco and existing traditional large diameter wells located in this aquifer. In order to assess the infiltration capacity of the existing infrastructures, in particular infiltration basins and large diameter wells at CF aquifer, infiltration tests were performed, indicating a high infiltration capacity of the existing infrastructures. Concerning the sources of water for recharge, harvested rainwater at greenhouses was identified in CF aquifer area as one of the main potential sources for aquifer recharge, once there is a large surface area occupied by these infrastructures at the demo site. This potential source of water could, in some cases, be redirected to the large diameter wells or to the infiltration basins at the riverbed of Rio Seco. Estimates of rainwater harvested at greenhouses were calculated based on a 32 year average rainfall model and on the location of the greenhouses and their surface areas, the latter based on aerial photograph. Potential estimated annual rainwater intercepted by greenhouses at CF aquifer accounts an average of 1.63 hm3/year. Nonetheless it is unlikely that the totality of this amount can be harvested, collected and redirected to aquifer recharge infrastructures, for several reasons, such as the lack of appropriate greenhouse infrastructures, conduits or a close location between greenhouses and large diameter wells and infiltration basins. Anyway, this value is a good indication of the total amount of the harvested rainfall that could be considered for future MAR solutions. Given the estimates on the greenhouse harvested rainwater and the infiltration capacity of the infiltration basins and large diameter wells, it is intended to develop groundwater flow models in order to assess the nitrate washing rate in the CF aquifer. This work is being developed under the scope of MARSOL Project (MARSOL-GA-2013-619120), in which Campina de Faro aquifer system is one of the several case studies. This project aims to demonstrate that MAR is a sound, safe and sustainable strategy that can be applied with great confidence in finding solutions to water scarcity in Southern Europe.

Distribution of POPs, pesticides and antibiotic residues in organic honeys from different production areas.

PubMed

Chiesa, Luca Maria; Panseri, Sara; Nobile, Maria; Ceriani, Federica; Arioli, Francesco

2018-06-22

Demand for honey is increasing, especially if it is organic and if its nutritional properties are linked to untreated environments in order to guarantee quality for health. Sources of contamination of honey can be divided into environmental and apicultural. Therefore, the distribution of persistent organic pollutants, pesticides and antibiotic residues from geographical areas with different contamination sources (high anthropic impact, intensive farming, husbandry and low anthropic impact) was investigated in order to confirm the potential transfer of xenobiotics into the supply chain and to give beekeepers tools for the selection of areas dedicated to organic production. The presence of polychlorinated biphenyls, polybrominated diphenyl ether and polycyclic aromatic hydrocarbons was confirmed, not only in proximity to highly urbanised centres, where the concentrations were higher, but in all environment contexts, confirming their ubiquity. No antibiotics or neonicotinoids were detected in 95 organic honeys, demonstrating the absence of apicultural treatments and consequently the good quality of honey of different areas. These results are important due to the undefined regulatory European situation on honey antibiotic limits.[Figure: see text].

Superfund record of decision (EPA Region 5): Skinner Landfill, West Chester, OH, June 1993

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1993-06-04

The decision document presents the selected final remedial action for the Skinner Landfill site in West Chester, Ohio. The remedy is the second and final of two operable units for this site. The first operable unit addressed immediate site concerns, through the construction of a fence around the contaminated area, and by offering an alternate supply of drinking water to the potentially affected users of groundwater. This final operable unit addresses potential future migration of site contaminants into the groundwater and will limit the potential for direct exposure of site contaminants to humans through source control measures.

Sources of nitrogen and phosphorus emissions to Irish rivers: estimates from the Source Load Apportionment Model (SLAM)

NASA Astrophysics Data System (ADS)

Mockler, Eva; Deakin, Jenny; Archbold, Marie; Daly, Donal; Bruen, Michael

2017-04-01

More than half of the river and lake water bodies in Europe are at less than good ecological status or potential, and diffuse pollution from agriculture remains a major, but not the only, cause of this poor performance. In Ireland, it is evident that agri-environmental policy and land management practices have, in many areas, reduced nutrient emissions to water, mitigating the potential impact on water quality. However, additional measures may be required in order to further decouple the relationship between agricultural productivity and emissions to water, which is of vital importance given the on-going agricultural intensification in Ireland. Catchment management can be greatly supported by modelling, which can reduce the resources required to analyse large amounts of information and can enable investigations and measures to be targeted. The Source Load Apportionment Model (SLAM) framework was developed to support catchment management in Ireland by characterising the contributions from various sources of phosphorus (P) and nitrogen (N) emissions to water. The SLAM integrates multiple national spatial datasets relating to nutrient emissions to surface water, including land use and physical characteristics of the sub-catchments to predict emissions from point (wastewater, industry discharges and septic tank systems) and diffuse sources (agriculture, forestry, peatlands, etc.). The annual nutrient emissions predicted by the SLAM were assessed against nutrient monitoring data for 16 major river catchments covering 50% of the area of Ireland. At national scale, results indicate that the total average annual emissions to surface water in Ireland are over 2,700 t yr-1 of P and 80,000 t yr-1 of N. The SLAM results include the proportional contributions from individual sources at a range of scales from sub-catchment to national, and show that the main sources of P are from wastewater and agriculture, with wide variations across the country related to local anthropogenic pressures and the hydrogeological setting. Agriculture is the main source of N emissions to water across all regions of Ireland. The SLAM results have been incorporated into an Integrated Catchment Management process and used in conjunction with monitoring data and local knowledge during the characterisation of all Irish water bodies by the Environmental Protection Agency. This demonstrates the successful integration of research into catchment management to inform the identification of (i) the sources of nutrients at regional and local scales and (ii) the potential significant pressures and appropriate mitigation measures.

Comparison of fluid-fluid interfacial areas measured with X-ray microtomography and interfacial partitioning tracer tests for the same samples: COMPARISON OF FLUID-FLUID INTERFACIAL AREAS

DOE Office of Scientific and Technical Information (OSTI.GOV)

McDonald, Kieran; Carroll, Kenneth C.; Brusseau, Mark L.

2016-07-01

Two different methods are currently used for measuring interfacial areas between immiscible fluids within 3-D porous media, high-resolution microtomographic imaging and interfacial partitioning tracer tests (IPTT). Both methods were used in this study to measure nonwetting/wetting interfacial areas for a natural sand. The microtomographic imaging was conducted on the same packed columns that were used for the IPTTs. This is in contrast to prior studies comparing the two methods, for which in all cases different samples were used for the two methods. In addition, the columns were imaged before and after the IPTTs to evaluate the potential impacts of themore » tracer solution on fluid configuration and attendant interfacial area. The interfacial areas measured using IPTT are ~5 times larger than the microtomographic-measured values, which is consistent with previous work. Analysis of the image data revealed no significant impact of the tracer solution on NAPL configuration or interfacial area. Other potential sources of error were evaluated, and all were demonstrated to be insignificant. The disparity in measured interfacial areas between the two methods is attributed to the limitation of the microtomography method to characterize interfacial area associated with microscopic surface roughness due to resolution constraints.« less

Seasonal and Spatial Variations of Heavy Metals in Two Typical Chinese Rivers: Concentrations, Environmental Risks, and Possible Sources

PubMed Central

Yao, Hong; Qian, Xin; Gao, Hailong; Wang, Yulei; Xia, Bisheng

2014-01-01

Ten metals were analyzed in samples collected in three seasons (the dry season, the early rainy season, and the late rainy season) from two rivers in China. No observed toxic effect concentrations were used to estimate the risks. The possible sources of the metals in each season, and the dominant source(s) at each site, were assessed using principal components analysis. The metal concentrations in the area studied were found, using t-tests, to vary both seasonally and spatially (P = 0.05). The potential risks in different seasons decreased in the order: early rainy season > dry season > late rainy season, and Cd was the dominant contributor to the total risks associated with heavy metal pollution in the two rivers. The high population and industrial site densities in the Taihu basin have had negative influences on the two rivers. The river that is used as a source of drinking water (the Taipu River) had a low average level of risks caused by the metals. Metals accumulated in environmental media were the main possible sources in the dry season, and emissions from mechanical manufacturing enterprises were the main possible sources in the rainy season. The river in the industrial area (the Wusong River) had a moderate level of risk caused by the metals, and the main sources were industrial emissions. The seasonal and spatial distributions of the heavy metals mean that risk prevention and mitigation measures should be targeted taking these variations into account. PMID:25407421

Ambient concentrations and personal exposure to polycyclic aromatic hydrocarbons (PAH) in an urban community with mixed sources of air pollution.

PubMed

Zhu, Xianlei; Fan, Zhihua Tina; Wu, Xiangmei; Jung, Kyung Hwa; Ohman-Strickland, Pamela; Bonanno, Linda J; Lioy, Paul J

2011-01-01

Assessment of the health risks resulting from exposure to ambient polycyclic aromatic hydrocarbons (PAH) is limited by a lack of environmental exposure data among the general population. This study characterized personal exposure and ambient concentrations of PAH in the Village of Waterfront South (WFS), an urban community with many mixed sources of air toxics in Camden, New Jersey, and CopeWood/Davis Streets (CDS), an urban reference area located ∼1 mile east of WFS. A total of 54 and 53 participants were recruited from non-smoking households in WFS and CDS, respectively. In all, 24-h personal and ambient air samples were collected simultaneously in both areas on weekdays and weekends during summer and winter. The ambient PAH concentrations in WFS were either significantly higher than or comparable to those in CDS, indicating the significant impact of local sources on PAH pollution in WFS. Analysis of diagnostic ratios and correlation suggested that diesel truck traffic, municipal waste combustion and industrial combustion were the major sources in WFS. In such an area, ambient air pollution contributed significantly to personal PAH exposure, explaining 44-96% of variability in personal concentrations. This study provides valuable data for examining the impact of local ambient PAH pollution on personal exposure and therefore potential health risks associated with environmental PAH pollution.

Ambient concentrations and personal exposure to polycyclic aromatic hydrocarbons (PAH) in an urban community with mixed sources of air pollution

PubMed Central

ZHU, XIANLEI; FAN, ZHIHUA (TINA); WU, XIANGMEI; JUNG, KYUNG HWA; OHMAN-STRICKLAND, PAMELA; BONANNO, LINDA J.; LIOY, PAUL J.

2014-01-01

Assessment of the health risks resulting from exposure to ambient polycyclic aromatic hydrocarbons (PAH) is limited by a lack of environmental exposure data among the general population. This study characterized personal exposure and ambient concentrations of PAH in the Village of Waterfront South (WFS), an urban community with many mixed sources of air toxics in Camden, New Jersey, and CopeWood/Davis Streets (CDS), an urban reference area located ~1 mile east of WFS. A total of 54 and 53 participants were recruited from non-smoking households in WFS and CDS, respectively. In all, 24-h personal and ambient air samples were collected simultaneously in both areas on weekdays and weekends during summer and winter. The ambient PAH concentrations in WFS were either significantly higher than or comparable to those in CDS, indicating the significant impact of local sources on PAH pollution in WFS. Analysis of diagnostic ratios and correlation suggested that diesel truck traffic, municipal waste combustion and industrial combustion were the major sources in WFS. In such an area, ambient air pollution contributed significantly to personal PAH exposure, explaining 44–96% of variability in personal concentrations. This study provides valuable data for examining the impact of local ambient PAH pollution on personal exposure and therefore potential health risks associated with environmental PAH pollution. PMID:21364704

Airframe self-noise: Four years of research. [aircraft noise reduction for commercial aircraft

NASA Technical Reports Server (NTRS)

Hardin, J. C.

1976-01-01

A critical assessment of the state of the art in airframe self-noise is presented. Full-scale data on the intensity, spectra and directivity of this noise source are evaluated in the light of the comprehensive theory developed by Ffowcs-Williams and Hawkins. Vibration of panels on commercial aircraft is identified as a possible additional source of airframe noise. The present understanding and methods for prediction of other component sources - airfoils, struts, and cavities - are discussed, and areas for further research as well as potential methods for airframe noise reduction are identified. Finally, the various experimental methods which have been developed for airframe noise research are discussed and sample results are presented.

Recov'Heat: An estimation tool of urban waste heat recovery potential in sustainable cities

NASA Astrophysics Data System (ADS)

Goumba, Alain; Chiche, Samuel; Guo, Xiaofeng; Colombert, Morgane; Bonneau, Patricia

2017-02-01

Waste heat recovery is considered as an efficient way to increase carbon-free green energy utilization and to reduce greenhouse gas emission. Especially in urban area, several sources such as sewage water, industrial process, waste incinerator plants, etc., are still rarely explored. Their integration into a district heating system providing heating and/or domestic hot water could be beneficial for both energy companies and local governments. EFFICACITY, a French research institute focused on urban energy transition, has developed an estimation tool for different waste heat sources potentially explored in a sustainable city. This article presents the development method of such a decision making tool which, by giving both energetic and economic analysis, helps local communities and energy service companies to make preliminary studies in heat recovery projects.

The worldwide market for photovoltaics in the rural sector

NASA Technical Reports Server (NTRS)

Brainard, W. A.

1982-01-01

The worldwide market for stand-alone photovoltaic power systems in three specific segments of the rural sector were determined. The worldwide market for photovoltaic power systems for village power, cottage industry, and agricultural applications were addressed. The objectives of these studies were to: The market potential for small stand-alone photovoltaic power system in specific application areas was assessed. Technical, social and institutional barriers to PV utilization were identified. Funding sources available to potential users was also identified and marketing strategies appropriate for each sector were recommended to PV product manufacturers. The studies were prepared on the basis of data gathered from domestic sources and from field trips to representative countries. Both country-specific and sector-specific results are discussed, and broadly applicable barriers pertinent to international marketing of PV products are presented.

Toward more versatile and intuitive cortical brain machine interfaces

PubMed Central

Andersen, Richard A.; Kellis, Spencer; Klaes, Christian; Aflalo, Tyson

2015-01-01

Brain machine interfaces have great potential in neuroprosthetic applications to assist patients with brain injury and neurodegenerative diseases. One type of BMI is a cortical motor prosthetic which is used to assist paralyzed subjects. Motor prosthetics to date have typically used the motor cortex as a source of neural signals for controlling external devices. The review will focus on several new topics in the arena of cortical prosthetics. These include using 1) recordings from cortical areas outside motor cortex; 2) local field potentials (LFPs) as a source of recorded signals; 3) somatosensory feedback for more dexterous control of robotics; and 4) new decoding methods that work in concert to form an ecology of decode algorithms. These new advances hold promise in greatly accelerating the applicability and ease of operation of motor prosthetics. PMID:25247368