WorldWideScience

Sample records for groundwater post air

  1. Investigations of air and groundwater pollution of the rural environment

    Energy Technology Data Exchange (ETDEWEB)

    Kerenyi, Attila; Csorba, Peter (Institute of Applied Landscape Geography, Kossuth L. University, Debrecen (Hungary))

    1993-12-01

    Within the framework of landscape investigations in the environment of Cserepfalu-Bogacs, air and groundwater pollution was regularly monitored. Automatic instruments were used to measure SO[sub 2] content of the air for one day, and NO[sub x] content for the following day. Characteristic periods of the year were selected for air pollution, so that several weeks of continuous measurements in each season were obtained. The air pollution data measured in Cserepfalu are nearly always characteristic of the wider environment (background values). In the centre of Bogacs, SO[sub 2] pollution as a result of winter heating can be well observed; the amount of NO[sub x] is mostly determined by the increased traffic in summer. During a windless and very cold November, SO[sub 2] contamination in Bogacs greatly exceeded the permissible level. Groundwater examinations were carried out in the village of Cserepfalu between 1989 and 1990. The first measurements in Cserepfalu, between May and September 1988, showed little contamination, and the nitrate content was practically constant at 30 mg dm[sup -3] in the four main wells. In June 1989 the nitrate content of the water in these wells rose 4-7-fold by the end of the month. The characteristic nitrate concentration was found to be 80-150 mg dm[sup -3] and 150-250 mg dm[sup -3], but there were some places with values above 400 mg dm[sup -3]. These high values were found on the outskirts of the village, in an intensively cultivated agricultural area; thus the agricultural origin of the contamination is probable

  2. [Simulation on remediation of benzene contaminated groundwater by air sparging].

    Science.gov (United States)

    Fan, Yan-Ling; Jiang, Lin; Zhang, Dan; Zhong, Mao-Sheng; Jia, Xiao-Yang

    2012-11-01

    Air sparging (AS) is one of the in situ remedial technologies which are used in groundwater remediation for pollutions with volatile organic compounds (VOCs). At present, the field design of air sparging system was mainly based on experience due to the lack of field data. In order to obtain rational design parameters, the TMVOC module in the Petrasim software package, combined with field test results on a coking plant in Beijing, is used to optimize the design parameters and simulate the remediation process. The pilot test showed that the optimal injection rate was 23.2 m3 x h(-1), while the optimal radius of influence (ROI) was 5 m. The simulation results revealed that the pressure response simulated by the model matched well with the field test results, which indicated a good representation of the simulation. The optimization results indicated that the optimal injection location was at the bottom of the aquifer. Furthermore, simulated at the optimized injection location, the optimal injection rate was 20 m3 x h(-1), which was in accordance with the field test result. Besides, 3 m was the optimal ROI, less than the field test results, and the main reason was that field test reflected the flow behavior at the upper space of groundwater and unsaturated area, in which the width of flow increased rapidly, and became bigger than the actual one. With the above optimized operation parameters, in addition to the hydro-geological parameters measured on site, the model simulation result revealed that 90 days were needed to remediate the benzene from 371 000 microg x L(-1) to 1 microg x L(-1) for the site, and that the opeation model in which the injection wells were progressively turned off once the groundwater around them was "clean" was better than the one in which all the wells were kept operating throughout the remediation process.

  3. Hydrogeology, simulated ground-water flow, and ground-water quality, Wright-Patterson Air Force Base, Ohio

    Science.gov (United States)

    Dumouchelle, D.H.; Schalk, C.W.; Rowe, G.L.; De Roche, J.T.

    1993-01-01

    percent of the total ground-water flow in the study area. Ground waters in the vicinity of Wright-Patterson Air Force Base can be classified into two compositional groups on the basis of their chemical composition: calcium magnesium bicarbonate-type and sodium chloride-type waters. Calcium magnesium bicarbonate-type waters are found in the glacial deposits and the Brassfield Limestone, whereas the sodium chloride waters are exclusively associated with the shales. Equilibrium speciation calculations indicate that ground water of the glacial drift aquifer is in equilibrium with calcite, dolomite, and chalcedony, but is undersaturated with respect to gypsum and fluorite. Waters from the shales are slightly supersaturated with respect to calcite, dolomite, and siderite but are undersaturated with respect to chalcedony. Simple-mass balance calculations treating boron as a conservative species indicate that little (< 5 percent) or no recharge from the shales to the glacial drift aquifer takes place. Data on the stable isotopes of oxygen and hydrogen indicate a meteoric origin for all ground water beneath Wright-Patterson Air Force Base, but the data were inconclusive with respect to identification of distinct isotopic differences between water collected from the glacial drift and bedrock aquifers. Tritium concentrations used to distinguish waters having a pre-and post-1953 recharge component indicate that most water entered the glacial drift aquifer after 1953. This finding indicates that recharge from shallow to deep parts (greater than 150 feet) of the aquifer takes place over time intervals of a few years or decades. However, the fact that some deep parts of the glacial aquifer did not contain measurable tritium indicates that ground-water flow from recharge zones to these parts of the aquifer takes decades or longer.

  4. PHYTOREMEDIATION OF GROUNDWATER AT AIR FORCE PLANT 4, CARSWELL, TEXAS - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    Science.gov (United States)

    Over 600 Cottonwood trees were planted over a shallow groundwater plume in an attempt to detoxify the trichloroethylene (TCE) in a groundwater plume at a former Air Force facility. Two planting techniques were used: rooted stock about two years old, and 18 inch cuttings were inst...

  5. PHYTOREMEDIATION OF GROUNDWATER AT AIR FORCE PLANT 4, CARSWELL, TEXAS - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    Science.gov (United States)

    Over 600 Cottonwood trees were planted over a shallow groundwater plume in an attempt to detoxify the trichloroethylene (TCE) in a groundwater plume at a former Air Force facility. Two planting techniques were used: rooted stock about two years old, and 18 inch cuttings were inst...

  6. Development of dual-source hybrid heat pump system using groundwater and air

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Yujin; Ooka, Ryozo [Cw403 Institute of Industry Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505 (Japan); Shiba, Yoshiro [Zeneral Heatpump Industry Co., Ltd., Nagoya 459-8001 (Japan)

    2010-06-15

    To achieve high heat pump efficiency, groundwater heat pump (GWHP) system uses groundwater, which is relatively stable AT temperature compared with outdoor air, as a heat source. However, it is difficult to meet annual heating and cooling loads using only groundwater as a heat source. In order to optimize the operation method of GWHP systems, it is necessary to develop a system utilizing both groundwater and air sources according to the building load conditions. Furthermore, during intermediate seasons (such as spring and autumn) with reduced heating and cooling loads, GWHP system is less efficient than air source heat pump (ASHP) system according to temperature conditions. In order to more efficiently use GWHP systems, it is necessary to develop a system which utilizes both groundwater and air sources according to temperature conditions and building loads. This research has developed a GWHP system that employs a hybrid heat pump system with groundwater wells using dual groundwater and air heat sources. In this paper, the annual performance of the developed system has been calculated, and several case studies have been conducted on the effect of introduction location, refrigerant and pumping rate. Furthermore, the coefficient of system performance and the effects on underground environments have been evaluated by real-scale experiment using two wells. (author)

  7. Groundwater.

    Science.gov (United States)

    Braids, Olin C.; Gillies, Nola P.

    1978-01-01

    Presents a literature review of groundwater quality covering publications of 1977. This review includes: (1) sources of groundwater contamination; and (2) management of groundwater. A list of 59 references is also presented. (HM)

  8. Assessment of quality and geochemical processes occurring in groundwaters near central air conditioning plant site in Trombay, Maharashtra, India.

    Science.gov (United States)

    Tirumalesh, K; Shivanna, K; Sriraman, A K; Tyagi, A K

    2010-04-01

    This paper summarizes the findings obtained in a monitoring study to understand the sources and processes affecting the quality of shallow and deep groundwater near central air conditioning plant site in Trombay region by making use of physicochemical and biological analyses. All the measured parameters of the groundwaters indicate that the groundwater quality is good and within permissible limits set by (Indian Bureau of Standards 1990). Shallow groundwater is dominantly of Na-HCO(3) type whereas deep groundwater is of Ca-Mg-HCO(3) type. The groundwater chemistry is mainly influenced by dissolution of minerals and base exchange processes. High total dissolved solids in shallow groundwater compared to deeper ones indicate faster circulation of groundwater in deep zone preferably through fissures and fractures whereas groundwater flow is sluggish in shallow zone. The characteristic ionic ratio values and absence of bromide point to the fact that seawater has no influence on groundwater system.

  9. China Post Expects High of“Air Express Service”

    Institute of Scientific and Technical Information of China (English)

    ByTangXiaolin

    2004-01-01

    Within two weeks of developing the Shanghai-Japan“ next day delivery”service jointly with China Southern Airlines, China Post again on December 19,2003 held a grand foundation laying ceremony at the New Baiyun International Airport of Guangzhou for the joint establishment of Guangzhou Air Mail & Logistics Handle Center with China Post Guangdong.

  10. The role of soil air composition for noble gas tracer applications in tropical groundwater

    Science.gov (United States)

    Mayer, Simon; Jenner, Florian; Aeschbach, Werner; Weissbach, Therese; Peregovich, Bernhard; Machado, Carlos

    2016-04-01

    Dissolved noble gases (NGs) in groundwater provide a well-established tool for paleo temperature reconstruction. However, reliable noble gas temperature (NGT) determination needs appropriate assumptions or rather an exact knowledge of soil air composition. Deviations of soil air NG partial pressures from atmospheric values have already been found in mid latitudes during summer time as a consequence of subsurface oxygen depletion. This effect depends on ambient temperature and humidity and is thus expected to be especially strong in humid tropical soils, which was not investigated so far. We therefore studied NGs in soil air and shallow groundwater near Santarém (Pará, Brazil) at the end of the rainy and dry seasons, respectively. Soil air data confirms a correlation between NG partial pressures, the sum value of O2+CO2 and soil moisture contents. During the rainy season, we find significant NG enhancements in soil air by up to 7% with respect to the atmosphere. This is twice as much as observed during the dry season. Groundwater samples show neon excess values between 15% and 120%. Nearly all wells show no seasonal variations of excess air, even though the local river level seasonally fluctuates by about 8 m. Assuming atmospheric NG contents in soil air, fitted NGTs underestimate the measured groundwater temperature by about 1-2° C. However, including enhanced soil air NG contents as observed during the rainy season, resulting NGTs are in good agreement with local groundwater temperatures. Our presented data allows for a better understanding of subsurface NG variations. This is essential with regard to NG tracer applications in humid tropical areas, for which reliable paleoclimate data is of major importance for modern climate research.

  11. Groundwater pollution of post-mined phosphate rock in Tuojiang watershed (Sichuan, China)

    Science.gov (United States)

    changwen, ye

    2014-05-01

    Phosphate rock is the source of phosphorus used to make phosphatic fertilizers, essential for growing the food needed by humans in the world today and in the future. The erosion and eluviation on exposed phosphrite layer and overburden in the phosphate rock areas result in the releasing of fluoride and phosphorus and groundwater polluting. Meanwhile, the waste water and untreated mineral waste residue in the beneficiation and mining operations are also main source of pollution. The un-restored post-mined phosphate rock areas in Tuojiang watershed is large scale. The investigation of the amounts of pollutants releasing from mined lands and transporting by runoffs was conducted. The releasing and transporting amounts of pollutants were calculated according to the results of column leaching studies and acreages of exposed phosphrite layers and overburdens. In conclusion, phosphorus mining activity is an important non-point source of groundwater contamination of Tuojiang watershed.Study about the management and engineering measurement can be carried out according to the non-point source: agriculture, Pollution, Phosphorous mine and chemical plant. The study can provide the practical consultation and help making the decision about the management and treatment of groundwater resource in Tuojiang watershed. Keywords: Tuojiang watershed; Groundwater pollution; Losing process; Fluorine; Phosphorus

  12. Post-Service Utilization of Air Force-Gained Skills.

    Science.gov (United States)

    Winkler, Anthony J.; Thompson, Paul D.

    More complete information is needed to determine the extent of utilization in the civilian economy of skills developed during military service. Post-service occupation data have been obtained through a questionnaire mailed ten months after separation to each first-term Air Force enlisted man separated between 1 July 1968 and 31 March 1970. As of…

  13. Pre/post-closure assessment of groundwater pharmaceutical fate in a wastewater‑facility-impacted stream reach

    Science.gov (United States)

    Bradley, Paul M.; Barber, Larry B.; Clark, Jimmy M.; Duris, Joseph; Foreman, William; Furlong, Edward T.; Givens, Carrie E.; Hubbard, Laura E.; Hutchinson, Kasey J.; Journey, Celeste A.; Keefe, Steffanie H.; Kolpin, Dana W.

    2016-01-01

    Pharmaceutical contamination of contiguous groundwater is a substantial concern in wastewater-impacted streams, due to ubiquity in effluent, high aqueous mobility, designed bioactivity, and to effluent-driven hydraulic gradients. Wastewater treatment facility (WWTF) closures are rare environmental remediation events; offering unique insights into contaminant persistence, long-term wastewater impacts, and ecosystem recovery processes. The USGS conducted a combined pre/post-closure groundwater assessment adjacent to an effluent-impacted reach of Fourmile Creek, Ankeny, Iowa, USA. Higher surface-water concentrations, consistent surface-water to groundwater concentration gradients, and sustained groundwater detections tens of meters from the stream bank demonstrated the importance of WWTF effluent as the source of groundwater pharmaceuticals as well as the persistence of these contaminants under effluent-driven, pre-closure conditions. The number of analytes (110 total) detected in surface water decreased from 69 prior to closure down to 8 in the first post-closure sampling event approximately 30 d later, with a corresponding 2 order of magnitude decrease in the cumulative concentration of detected analytes. Post-closure cumulative concentrations of detected analytes were approximately 5 times higher in proximal groundwater than in surface water. About 40% of the 21 contaminants detected in a downstream groundwater transect immediately before WWTF closure exhibited rapid attenuation with estimated half-lives on the order of a few days; however, a comparable number exhibited no consistent attenuation during the year-long post-closure assessment. The results demonstrate the potential for effluent-impacted shallow groundwater systems to accumulate pharmaceutical contaminants and serve as long-term residual sources, further increasing the risk of adverse ecological effects in groundwater and the near-stream ecosystem.

  14. Evaluation of Pre- and Post- Redevelopment Groundwater Chemical Analyses from LM Monitoring Wells

    Energy Technology Data Exchange (ETDEWEB)

    Kamp, Susan [Navarro Reserch and Engineering, Oak Ridge, TN (United States); Dayvault, Jalena [US Department of Energy, Washington, DC (United States). Office of Legacy Management

    2016-05-01

    This report documents the efforts and analyses conducted for the Applied Studies and Technology (AS&T) Ancillary Work Plan (AWP) project titled Evaluation of Pre- and Post- Redevelopment Groundwater Sample Laboratory Analyses from Selected LM Groundwater Monitoring Wells. This effort entailed compiling an inventory of nearly 500 previous well redevelopment events at 16 U.S. Department of Energy Office of Legacy Management (LM) sites, searching the literature for impacts of well redevelopment on groundwater sample quality, and—the focus of this report—evaluating the impacts of well redevelopment on field measurements and sample analytical results. Study Catalyst Monitoring well redevelopment, the surging or high-volume pumping of a well to loosen and remove accumulated sediment and biological build-up from a well, is considered an element of monitoring well maintenance that is implemented periodically during the lifetime of the well to mitigate its gradual deterioration. Well redevelopment has been conducted fairly routinely at a few LM sites in the western United States (e.g., the Grand Junction office site and the Gunnison processing site in Colorado), but at most other sites in this region it is not a routine practice. Also, until recently (2014–2015), there had been no specific criteria for implementing well redevelopment, and documentation of redevelopment events has been inconsistent. A catalyst for this evaluation was the self-identification of these inconsistencies by the Legacy Management Support contractor. As a result, in early 2015 Environmental Monitoring Operations (EMO) staff began collecting and documenting additional field measurements during well redevelopment events. In late 2015, AS&T staff undertook an independent internal evaluation of EMO's well redevelopment records and corresponding pre- and post-well-redevelopment groundwater analytical results. Study Findings Although literature discussions parallel the prevailing industry

  15. Evaluation of radon occurrence in groundwater from 16 geologic units in Pennsylvania, 1986–2015, with application to potential radon exposure from groundwater and indoor air

    Science.gov (United States)

    Gross, Eliza L.

    2017-05-11

    Results from 1,041 groundwater samples collected during 1986‒2015 from 16 geologic units in Pennsylvania, associated with 25 or more groundwater samples with concentrations of radon-222, were evaluated in an effort to identify variations in radon-222 activities or concentrations and to classify potential radon-222 exposure from groundwater and indoor air. Radon-222 is hereafter referred to as “radon.” Radon concentrations in groundwater greater than or equal to the proposed U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) for public-water supply systems of 300 picocuries per liter (pCi/L) were present in about 87 percent of the water samples, whereas concentrations greater than or equal to the proposed alternative MCL (AMCL) for public water-supply systems of 4,000 pCi/L were present in 14 percent. The highest radon concentrations were measured in groundwater from the schists, gneisses, and quartzites of the Piedmont Physiographic Province.In this study, conducted by the U.S. Geological Survey in cooperation with the Pennsylvania Department of Health and the Pennsylvania Department of Environmental Protection, groundwater samples were aggregated among 16 geologic units in Pennsylvania to identify units with high median radon concentrations in groundwater. Graphical plots and statistical tests were used to determine variations in radon concentrations in groundwater and indoor air. Median radon concentrations in groundwater samples and median radon concentrations in indoor air samples within the 16 geologic units were classified according to proposed and recommended regulatory limits to explore potential radon exposure from groundwater and indoor air. All of the geologic units, except for the Allegheny (Pa) and Glenshaw (Pcg) Formations in the Appalachian Plateaus Physiographic Province, had median radon concentrations greater than the proposed EPA MCL of 300 pCi/L, and the Peters Creek Schist (Xpc), which is in the Piedmont

  16. PHYTOREMEDIATION OF GROUNDWATER AT AIR FORCE PLANT 4, CARSWELL, TEXAS - INNOVATIVE TECHNOLOGY EVALUATION REPORT (CD-ROM)

    Science.gov (United States)

    Over 600 Cottonwood trees were planted over a shallow groundwater plume in an attempt to detoxify the tricWoroethylene (TCE) in a groundwater plume at a former Air Force facility. Two planting techniques were used: rooted stock about two years old, and 18 inch cuttings were insta...

  17. PHYTOREMEDIATION OF GROUNDWATER AT AIR FORCE PLANT 4, CARSWELL, TEXAS - INNOVATIVE TECHNOLOGY EVALUATION REPORT (CD-ROM)

    Science.gov (United States)

    Over 600 Cottonwood trees were planted over a shallow groundwater plume in an attempt to detoxify the tricWoroethylene (TCE) in a groundwater plume at a former Air Force facility. Two planting techniques were used: rooted stock about two years old, and 18 inch cuttings were insta...

  18. Superfund record of decision (EPA Region 9): McClellan Air Force Base, Basewide Groundwater Operable Unit, Sacramento, CA, May 11, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The Interim Record of Decision (ROD) presents the interim remedial action for the Groundwater Operable Unit (Groundwater OU) at the McClellan Air Force Base (McClellan AFB) Superfund site in Sacramento, California. The Groundwater OU addresses all of the VOC-contaminated groundwater at McClellan AFB. The Groundwater OU remedy is designed to prevent the spread of contamination that is already in the groundwater by containing groundwater with concentrations greater than maximum contaminant levels (MCLs). The remedy is also designed to remove to the maximum extent practicable the mass of contamination that lies in that volume of the groundwater.

  19. Simulating an exclusion zone for vapour intrusion of TCE from groundwater into indoor air.

    Science.gov (United States)

    Wang, Xiaomin; Unger, Andre J A; Parker, Beth L

    2012-10-01

    This paper is an extension of the work by Yu et al. (2009) to examine exposure pathways of volatile organic compounds (VOCs) originating from a NAPL source zone located below the water table, and their potential impact on multiple residential dwellings down-gradient of the source zone. The three-dimensional problem geometry is based on the Rivett (1995) field experiment in the Borden aquifer, and contains houses located both above and adjacent to the groundwater plume in order to define an exclusion zone. Simulation results using the numerical model CompFlow Bio indicate that houses which are laterally offset from the groundwater plume are less affected by vapour intrusion than those located directly above the plume due to limited transverse horizontal flux of TCE within the groundwater plume, in agreement with the ASTM (2008) guidance. Uncertainty in the simulated indoor air concentration is sensitive to heterogeneity in the permeability structure of a stratigraphically continuous aquifer, with uncertainty defined as the probability of simulated indoor air concentrations exceeding the NYSDOH (2005) regulatory limit. Within this uncertainty framework, this work shows that the Johnson and Ettinger (1991), ASTM (2008) and CompFlow Bio models all delineate an identical exclusion zone at a 99.9% confidence interval of indoor air concentrations based on the probability of exceedence.

  20. Evaluation of Pre- and Post- Redevelopment Groundwater Chemical Analyses from LM Monitoring Wells

    Energy Technology Data Exchange (ETDEWEB)

    Kamp, Susan [Navarro Reserch and Engineering, Oak Ridge, TN (United States); Dayvault, Jalena [US Department of Energy, Washington, DC (United States). Office of Legacy Management

    2016-05-01

    This report documents the efforts and analyses conducted for the Applied Studies and Technology (AS&T) Ancillary Work Plan (AWP) project titled Evaluation of Pre- and Post- Redevelopment Groundwater Sample Laboratory Analyses from Selected LM Groundwater Monitoring Wells. This effort entailed compiling an inventory of nearly 500 previous well redevelopment events at 16 U.S. Department of Energy Office of Legacy Management (LM) sites, searching the literature for impacts of well redevelopment on groundwater sample quality, and—the focus of this report—evaluating the impacts of well redevelopment on field measurements and sample analytical results. Study Catalyst Monitoring well redevelopment, the surging or high-volume pumping of a well to loosen and remove accumulated sediment and biological build-up from a well, is considered an element of monitoring well maintenance that is implemented periodically during the lifetime of the well to mitigate its gradual deterioration. Well redevelopment has been conducted fairly routinely at a few LM sites in the western United States (e.g., the Grand Junction office site and the Gunnison processing site in Colorado), but at most other sites in this region it is not a routine practice. Also, until recently (2014–2015), there had been no specific criteria for implementing well redevelopment, and documentation of redevelopment events has been inconsistent. A catalyst for this evaluation was the self-identification of these inconsistencies by the Legacy Management Support contractor. As a result, in early 2015 Environmental Monitoring Operations (EMO) staff began collecting and documenting additional field measurements during well redevelopment events. In late 2015, AS&T staff undertook an independent internal evaluation of EMO's well redevelopment records and corresponding pre- and post-well-redevelopment groundwater analytical results. Study Findings Although literature discussions parallel the prevailing industry

  1. Groundwater level and nitrate concentration trends on Mountain Home Air Force Base, southwestern Idaho

    Science.gov (United States)

    Williams, Marshall L.

    2014-01-01

    Mountain Home Air Force Base in southwestern Idaho draws most of its drinking water from the regional aquifer. The base is located within the State of Idaho's Mountain Home Groundwater Management Area and is adjacent to the State's Cinder Cone Butte Critical Groundwater Area. Both areas were established by the Idaho Department of Water Resources in the early 1980s because of declining water levels in the regional aquifer. The base also is listed by the Idaho Department of Environmental Quality as a nitrate priority area. The U.S. Geological Survey, in cooperation with the U.S. Air Force, began monitoring wells on the base in 1985, and currently monitors 25 wells for water levels and 17 wells for water quality, primarily nutrients. This report provides a summary of water-level and nitrate concentration data collected primarily between 2001 and 2013 and examines trends in those data. A Regional Kendall Test was run to combine results from all wells to determine an overall regional trend in water level. Groundwater levels declined at an average rate of about 1.08 feet per year. Nitrate concentration trends show that 3 wells (18 percent) are increasing in nitrate concentration trend, 3 wells (18 percent) show a decreasing nitrate concentration trend, and 11 wells (64 percent) show no nitrate concentration trend. Six wells (35 percent) currently exceed the U.S. Environmental Protection Agency's maximum contaminant limit of 10 milligrams per liter for nitrate (nitrite plus nitrate, measured as nitrogen).

  2. Evaluation of short-term tracer fluctuations in groundwater and soil air in a two year study

    Science.gov (United States)

    Jenner, Florian; Mayer, Simon; Aeschbach, Werner; Weissbach, Therese

    2016-04-01

    The application of gas tracers like noble gases (NGs), SF6 or CFCs in groundwater studies such as paleo temperature determination requires a detailed understanding of the dynamics of reactive and inert gases in the soil air with which the infiltrating water equilibrates. Due to microbial gas consumption and production, NG partial pressures in soil air can deviate from atmospheric air, an effect that could bias noble gas temperatures estimates if not taken into account. So far, such an impact on NG contents in groundwater has not been directly demonstrated. We provide the first long-term study of the above mentioned gas tracers and physical parameters in both the saturated and unsaturated soil zone, sampled continuously for more than two years near Mannheim (Germany). NG partial pressures in soil air correlate with soil moisture and the sum value of O2+CO2, with a maximal significant enhancement of 3-6% with respect to atmospheric air during summer time. Observed seasonal fluctuations result in a mass dependent fractionation of NGs in soil air. Concentrations of SF6 and CFCs in soil air are determined by corresponding fluctuations in local atmospheric air, caused by industrial emissions. Arising concentration peaks are damped with increasing soil depth. Shallow groundwater shows short-term NG fluctuations which are smoothed within a few meters below the water table. A correlation between NG contents of soil air and of groundwater is observable during strong recharge events. However, there is no evidence for a permanent influence of seasonal variations of soil air composition on shallow groundwater. Fluctuating NG contents in shallow groundwater are rather determined by variations of soil temperature and water table level. Our data gives evidence for a further temperature driven equilibration of groundwater with entrapped air bubbles within the topmost saturated zone, which permanently occurs even some years after recharge. Local subsurface temperature fluctuations

  3. Groundwater remediation engineering--Study on the flow distribution of air sparging using acetylene

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yan-mei; ZHANG Ying; HUANG Guo-qiang; JIANG Bin; LI Xin-gang

    2005-01-01

    Air sparging(AS) is an emerging method to remove VOCs from saturated soils and groundwater. Air sparging performance highly depends on the air distribution resulting in the aquifer. In order to study gas flow characterization, a two-dimensional experimental chamber was designed and installed. In addition, the method by using acetylene as the tracer to directly image the gas distribution results of AS process has been put forward. Experiments were performed with different injected gas flow rates. The gas flow patterns were found to depend significantly on the injected gas flow rate, and the characterization of gas flow distributions in porous media was very different from the acetylene tracing study. Lower and higher gas flow rates generally yield more irregular in shape and less effective gas distributions.

  4. [Groundwater].

    Science.gov (United States)

    González De Posada, Francisco

    2012-01-01

    From the perspective of Hydrogeology, the concept and an introductory general typology of groundwater are established. From the perspective of Geotechnical Engineering works, the physical and mathematical equations of the hydraulics of permeable materials, which are implemented, by electric analogical simulation, to two unique cases of global importance, are considered: the bailing during the construction of the dry dock of the "new shipyard of the Bahia de Cádiz" and the waterproofing of the "Hatillo dam" in the Dominican Republic. From a physical fundamental perspective, the theories which are the subset of "analogical physical theories of Fourier type transport" are related, among which the one constituted by the laws of Adolf Fick in physiology occupies a historic role of some relevance. And finally, as a philosophical abstraction of so much useful mathematical process, the one which is called "the Galilean principle of the mathematical design of the Nature" is dealt with.

  5. Comparative study of urban development and groundwater condition in coastal areas of Buenos Aires, Argentina

    Science.gov (United States)

    Rodrigues Capítulo, Leandro; Carretero, Silvina C.; Kruse, Eduardo E.

    2017-08-01

    The geomorphological evolution of a sand-dune barrier in Buenos Aires, Argentina, is analyzed as a factor regulating the fresh groundwater reserves available. The impact of geomorphological evolution and the consequences for the social and economic development of two coastal areas are assessed. This is one of the most important tourist destinations in the country; for study purposes, it was divided into a northern sector and a southern sector. In the southern sector, the exploitable groundwater is associated with the Holocene and upper Pleistocene geomorphological evolution, which generated three interrelated aquifer units, constituting a system whose useful thickness reaches at least 45 m. In contrast, the northern sector is restricted to two Holocene aquifer units, whose total thickness is on the order of 12 m. The morphological characteristics and the occurrence of the largest fresh groundwater reserves in the southern sector are indicators of better conditions for economic growth, which is mainly reflected on the expansion of real estate ventures. The relationships of transmissivity vs area of real estate ventures (Arev), and total water consumption vs Arev, are indicators for the sustainable management of the water resources. The approach chosen may be used by decision makers in other regions to assess the feasibility of future tourism projects on the basis of the availability of water resources associated with geomorphological features.

  6. Comparative study of urban development and groundwater condition in coastal areas of Buenos Aires, Argentina

    Science.gov (United States)

    Rodrigues Capítulo, Leandro; Carretero, Silvina C.; Kruse, Eduardo E.

    2017-02-01

    The geomorphological evolution of a sand-dune barrier in Buenos Aires, Argentina, is analyzed as a factor regulating the fresh groundwater reserves available. The impact of geomorphological evolution and the consequences for the social and economic development of two coastal areas are assessed. This is one of the most important tourist destinations in the country; for study purposes, it was divided into a northern sector and a southern sector. In the southern sector, the exploitable groundwater is associated with the Holocene and upper Pleistocene geomorphological evolution, which generated three interrelated aquifer units, constituting a system whose useful thickness reaches at least 45 m. In contrast, the northern sector is restricted to two Holocene aquifer units, whose total thickness is on the order of 12 m. The morphological characteristics and the occurrence of the largest fresh groundwater reserves in the southern sector are indicators of better conditions for economic growth, which is mainly reflected on the expansion of real estate ventures. The relationships of transmissivity vs area of real estate ventures (Arev), and total water consumption vs Arev, are indicators for the sustainable management of the water resources. The approach chosen may be used by decision makers in other regions to assess the feasibility of future tourism projects on the basis of the availability of water resources associated with geomorphological features.

  7. Soil and groundwater VOCs contamination: How can electrical geophysical measurements help assess post-bioremediation state?

    Science.gov (United States)

    Kessouri, P.; Johnson, T. C.; Day-Lewis, F. D.; Slater, L. D.; Ntarlagiannis, D.; Johnson, C. D.

    2016-12-01

    The former Brandywine MD (Maryland, USA) Defense Reutilization and Marketing Office (DRMO) was designated a hazardous waste Superfund site in 1999. The site was used as a storage area for waste and excess government equipment generated by several U.S. Navy and U.S. Air Force installations, leading to soil and groundwater contamination by volatile organic compounds (VOCs). Active bioremediation through anaerobic reductive dehalogenation was used to treat the groundwater and the aquifer unconsolidated materials in 2008, with electrical geophysical measurements employed to track amendment injections. Eight years later, we used spectral induced polarization (SIP) and time domain induced polarization (TDIP) on 2D surface lines and borehole electrical arrays to assess the long term impact of active remediation on physicochemical properties of the subsurface. Within the aquifer, the treated zone is more electrically conductive, and the phase shift describing the polarization effects is higher than in the untreated zone. Bulk conductivity and phase shift are also locally elevated close to the treatment injection well, possibly due to biogeochemical transformations associated with prolonged bacterial activity. Observed SIP variations could be explained by the presence of biofilms coating the pore space and/or by-products of the chemical reactions catalyzed by the bacterial activity (e.g. iron sulfide precipitation). To investigate these possibilities, we conducted complementary well logging measurements (magnetic susceptibility [MS], nuclear magnetic resonance [NMR], gamma-ray) using 5 boreholes installed at both treated and untreated locations of the site. We also collected water and soil samples on which we conducted microbiological and chemical analyses, along with geophysical observations (SIP, MS and NMR), in the laboratory. These measurements provide further insights into the physicochemical transformations in the subsurface resulting from the treatment and highlight

  8. Measurements of HFC-134a and HCFC-22 in groundwater and unsaturated-zone air: implications for HFCs and HCFCs as dating tracers

    Science.gov (United States)

    Haase, Karl B.; Busenberg, Eurybiades; Plummer, L. Niel; Casile, Gerolamo; Sanford, Ward E.

    2014-01-01

    A new analytical method using gas chromatography with an atomic emission detector (GC–AED) was developed for measurement of ambient concentrations of hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) in soil, air, and groundwater, with the goal of determining their utility as groundwater age tracers. The analytical detection limits of HCFC-22 (difluorochloromethane, CHClF2) and HFC-134a (1,2,2,2-tetrafluoroethane, C2H2F4) in 1 L groundwater samples are 4.3 × 10− 1 and 2.1 × 10− 1 pmol kg− 1, respectively, corresponding to equilibrium gas-phase mixing ratios of approximately 5–6 parts per trillion by volume (pptv). Under optimal conditions, post-1960 (HCFC-22) and post-1995 (HFC-134a) recharge could be identified using these tracers in stable, unmixed groundwater samples. Ambient concentrations of HCFC-22 and HFC-134a were measured in 50 groundwater samples from 27 locations in northern and western parts of Virginia, Tennessee, and North Carolina (USA), and 3 unsaturated-zone profiles were collected in northern Virginia. Mixing ratios of both HCFC-22 and HFC-134a decrease with depth in unsaturated-zone gas profiles with an accompanying increase in CO2 and loss of O2. Apparently, ambient concentrations of HCFC-22 and HFC-134a are readily consumed by methanotrophic bacteria under aerobic conditions in the unsaturated zone. The results of this study indicate that soils are a sink for these two greenhouse gases. These observations contradict the previously reported results from microcosm experiments that found that degradation was limited above-ambient HFC-134a. The groundwater HFC and HCFC concentrations were compared with concentrations of chlorofluorocarbons (CFCs, CFC-11, CFC-12, CFC-113) and sulfur hexafluoride (SF6). Nearly all samples had measured HCFC-22 or HFC-134a that were below concentrations predicted by the CFCs and SF6, with many samples showing a complete loss of HCFC-22 and HFC-134a. This study indicates that HCFC-22 and HFC-134

  9. Modelling near subsurface temperature with mixed type boundary condition for transient air temperature and vertical groundwater flow

    Indian Academy of Sciences (India)

    Rajeev Ranjan Kumar; D V Ramana; R N Singh

    2012-10-01

    Near-subsurface temperatures have signatures of climate change. Thermal models of subsurface have been constructed by prescribing time dependent Dirichlet type boundary condition wherein the temperature at the soil surface is prescribed and depth distribution of temperature is obtained. In this formulation it is not possible to include the relationship between air temperatures and the temperature of soil surface. However, if one uses a Robin type boundary condition, a transfer coefficient relates the air and soil surface temperatures which helps to determine both the temperature at the surface and at depth given near surface air temperatures. This coefficient is a function of meteorological conditions and is readily available. We have developed such a thermal model of near subsurface region which includes both heat conduction and advection due to groundwater flows and have presented numerical results for changes in the temperature–depth profiles for different values of transfer coefficient and groundwater flux. There are significant changes in temperature and depth profiles due to changes in the transfer coefficient and groundwater flux. The analytical model will find applications in the interpretation of the borehole geothermal data to extract both climate and groundwater flow signals.

  10. Post-test evaluation of the geology, geochemistry, microbiology, and hydrology of the in situ air stripping demonstration site at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Eddy Dilek, C.A.; Looney, B.B.; Hazen, T.C.; Nichols, R.L.; Fliermans, C.B.; Parker, W.H.; Dougherty, J.M.; Kaback, D.S.; Simmons, J.L.

    1993-07-01

    A full-scale demonstration of the use of horizontal wells for in situ air stripping for environment restoration was completed as part of the Savannah River Integrated Demonstration Program. The demonstration of in situ air stripping was the first in a series of demonstrations of innovative remediation technologies for the cleanup of sites contaminated with volatile organic contaminants. The in situ air stripping system consisted of two directionally drilled wells that delivered gases to and extract contamination from the subsurface. The demonstration was designed to remediate soils and sediments in the unsaturated and saturated zones as well as groundwater contaminated with volatile organic compounds. The demonstration successfully removed significant quantities of solvent from the subsurface. The field site and horizontal wells were subsequently used for an in situ bioremediation demonstration during which methane was added to the injected air. The field conditions documented herein represent the baseline status of the site for evaluating the in situ bioremediation as well as the post-test conditions for the in situ air stripping demonstration. Characterization activities focused on documenting the nature and distribution of contamination in the subsurface. The post-test characterization activities discussed herein include results from the analysis of sediment samples, three-dimensional images of the pretest and post-test data, contaminant inventories estimated from pretest and post-test models, a detailed lithologic cross sections of the site, results of aquifer testing, and measurements of geotechnical parameters of undisturbed core sediments.

  11. Refrigeration, Heating & Air Conditioning. Post Secondary Curriculum Guide.

    Science.gov (United States)

    Garrison, Joe C.; And Others

    This curriculum guide was designed for use in postsecondary refrigeration, heating and air conditioning education programs in Georgia. Its purpose is to provide for the development of entry level skills in refrigeration, heating, and air conditioning in the areas of air conditioning knowledge, theoretical structure, tool usage, diagnostic ability,…

  12. Hydrogeology and simulation of ground-water flow at Arnold Air Force Base, Coffee and Franklin counties, Tennessee

    Science.gov (United States)

    Haugh, C.J.; Mahoney, E.N.

    1994-01-01

    The U.S. Air Force at Arnold Air Force Base (AAFB), in Coffee and Franklin Counties, Tennessee, is investigating ground-water contamination in selected areas of the base. This report documents the results of a comprehensive investigation of the regional hydrogeology of the AAFB area. Three aquifers within the Highland Rim aquifer system, the shallow aquifer, the Manchester aquifer, and the Fort Payne aquifer, have been identified in the study area. Of these, the Manchester aquifer is the primary source of water for domestic use. Drilling and water- quality data indicate that the Chattanooga Shale is an effective confining unit, isolating the Highland Rim aquifer system from the deeper, upper Central Basin aquifer system. A regional ground-water divide, approximately coinciding with the Duck River-Elk River drainage divide, underlies AAFB and runs from southwest to northeast. The general direction of most ground-water flow is to the north- west or to the northwest or to the southeast from the divide towards tributary streams that drain the area. Recharge estimates range from 4 to 11 inches per year. Digital computer modeling was used to simulate and provide a better understanding of the ground-water flow system. The model indicates that most of the ground-water flow occurs in the shallow and Manchester aquifers. The model was most sensitive to increases in hydraulic conductivity and changes in recharge rates. Particle-tracking analysis from selected sites of ground-water contamination indicates a potential for contami- nants to be transported beyond the boundary of AAFB.

  13. Performance of in-situ soil and groundwater treatment systems at McClellan Air Force Base

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, T.E. [BDM Federal, McClellan AFB, CA (United States); Mook, P.H. Jr.; Wong, K.B. [Sm-ALC/EMR, McClellan AFB, CA (United States)

    1997-12-31

    McClellan Air Force Base (AFB), located near Sacramento, California, is one of the Strategic Environmental Research and Development Program`s National Environmental Technology Test Sites. The US Air Force has evaluated, as part of the on-going environmental clean-up of McClellan AFB, several innovative and conventional in situ soil and groundwater technologies for the treatment of volatile organic compounds. This paper presents an overview and comparison of the performance and cost of three innovative technologies tested at McClellan AFB. Conventional groundwater extraction systems are effective but costly. Operation and maintenance (O and M) costs for treatment systems are increasingly becoming a major component of the environmental clean-up budget. The performance, limitations, costs, and lessons learned from the implementation of conventional soil vapor and groundwater extraction systems are compared with those of two innovative dual phase extraction systems. Both the Xerox 2-Phase{trademark} Extraction system and a standard dual phase extraction system are more effective than their conventional counterparts, but only over a discrete range of soil permeabilities. Discussions on McClellan AFB`s experiences with cometabolic bioremediation of groundwater and thermally enhanced soil vapor extraction systems are also included.

  14. Using radon-222 as indicator for the evaluation of the efficiency of groundwater remediation by in situ air sparging.

    Science.gov (United States)

    Schubert, Michael; Schmidt, Axel; Müller, Kai; Weiss, Holger

    2011-02-01

    A common approach for remediation of groundwater contamination with volatile organic compounds (VOCs) is contaminant stripping by means of in situ air sparging (IAS). For VOC stripping, pressurized air is injected into the contaminated groundwater volume, followed by the extraction of the contaminant-loaded exhaust gas from the vadose soil zone and its immediate on-site treatment. Progress assessment of such remediation measure necessitates information (i) on the spatial range of the IAS influence and (ii) on temporal variations of the IAS efficiency. In the present study it was shown that the naturally occurring noble gas radon can be used as suitable environmental tracer for achieving the related spatial and temporal information. Due to the distinct water/air partitioning behaviour of radon and due to its straightforward on-site detectability, the radon distribution pattern in the groundwater can be used as appropriate measure for assessing the progression of an IAS measure as a function of space and time. The presented paper discusses both the theoretical background of the approach and the results of an IAS treatment accomplished at a VOC contaminated site lasting six months, during which radon was applied as efficiency indicator.

  15. Correlation between geology and radon levels in groundwater, soil and indoor air in Bhilangana Valley, Garhwal Himalaya, India

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, V.M. [Wadia Inst. of Himalayan Geology, Dehra Dun (India); Ramola, R.C. [Dept. of Physics, H.N.B. Garhwal Univ. Campus, Tehri Garhwal (India)

    1997-11-01

    Radon concentrations were measured in soil, air and groundwater in Bhilangana Valley, Garhwal Himalaya, India by using an LR-115 plastic track detector and radon emanometer. Radon concentrations were found to vary from 1 KBq/m{sup 3} to 57 KBq/m{sup 3} in soil, 5 Bq/l to 887 Bq/l in water and 95 Bq/m{sup 3} to 208 Bq/m{sup 3} in air. The recorded values are quite high due to associated uranium mineralization in the area. Radon concentration was also found to depend on the tectonic structure and geology of the area. (orig.)

  16. Simulation of regional-scale groundwater flow in the Azul River basin, Buenos Aires Province, Argentina

    Science.gov (United States)

    Varni, Marcelo R.; Usunoff, Eduardo J.

    A three-dimensional modular model (MODFLOW) was used to simulate groundwater flow in the Azul River basin, Buenos Aires Province, Argentina, in order to assess the correctness of the conceptual model of the hydrogeological system. Simulated heads satisfactorily match observed heads in the regional water-table aquifer. Model results indicate that: (1) groundwater recharge is not uniform throughout the region but is best represented by three recharge rates, decreasing downgradient, similar to the distribution of soils and geomorphological characteristics; and (2) evapotranspiration rates are larger than previous estimates, which were made by using the Thornthwaite-Mather method. Evapotranspiration rates estimated by MODFLOW agree with results of independent studies of the region. Model results closely match historical surface-flow records, thereby suggesting that the model description of the aquifer-river relationship is correct. Résumé Un modèle modulaire tridimensionnel (MODFLOW) a été utilisé pour simuler les écoulements souterrains dans le bassin de la rivière Azul (Province de Buenos Aires, Argentine), dans le but d'évaluer la justesse du modèle conceptuel du système hydrogéologique. La piézométrie simulée s'ajuste de façon satisfaisante à celle observée pour l'ensemble de la nappe. Les résultats du modèle indiquent que: (1) la recharge de la nappe n'est pas uniforme sur toute la région, mais qu'elle est mieux approchée par trois valeurs différentes, décroissant vers l'aval-gradient, en suivant la même distribution que les sols et les caractéristiques géomorphologiques et (2) l'évapotranspiration est nettement plus importante que prévu initialement à partir de la méthode de Thornthwaite-Mather. Les valeurs d'évapotranspiration fournies par MODFLOW concordent bien avec les résultats d'autres études portant sur la région. Les résultats du modèle reproduisent convenablement les chroniques de débit des écoulements de surface

  17. Pre- and post-treatment enhance the protein enrichment from milling and air classification of legumes

    NARCIS (Netherlands)

    Pelgrom, P.J.M.; Wang, J.; Boom, R.M.; Schutyser, M.A.I.

    2015-01-01

    Air classification is a milder and more sustainable method to obtain protein-enriched fractions than commonly used wet fractionation. The protein content of air-classified fractions is generally lower than obtained with wet methods, therefore we applied pre- and post-treatments to increase the prote

  18. Curriculum Evolution at Air Command and Staff College in the Post-Cold War Era

    Science.gov (United States)

    Donovan, William Robert, II.

    2010-01-01

    This qualitative study used a historical research method to eliminate the gap in the historical knowledge of Air Command and Staff College (ACSC) curriculum evolution in the post-Cold War era. This study is the only known analysis of the forces that influenced the ACSC curriculum and the rationale behind curricular change at ACSC in the post-Cold…

  19. Hydrogeology and ground-water quality of the Chromic Acid Pit site, US Army Air Defense Artillery Center and Fort Bliss, El Paso, Texas

    Science.gov (United States)

    Abeyta, Cynthia G.; Thomas, C.L.

    1996-01-01

    The Chromic Acid Pit site is an inactive waste disposal site that is regulated by the Resource Conservation and Recovery Act of 1976. The 2.2-cubic-yard cement-lined pit was operated from 1980 to 1983 by a contractor to the U.S. Army Air Defense Artillery Center and Fort Bliss. The pit, located on the Fort Bliss military reservation, in El Paso, Texas, was used for disposal and evaporation of chromic acid waste generated from chrome plating operations. The site was certified closed in 1989 and the Texas Natural Resources Conservation Commission issued Permit Number HW-50296 (U.S. Environmental Protection Agency Permit Number TX4213720101), which approved and implemented post-closure care for the Chromic Acid Pit site. In accordance with an approved post-closure plan, the U.S. Geological Survey is cooperating with the U.S. Army in evaluating hydrogeologic conditions and ground- water quality at the site. One upgradient and two downgradient ground-water monitoring wells were installed adjacent to the chromic acid pit by a private contractor. Quarterly ground-water sampling of these wells by the U.S. Geological Survey began in December 1993. The Chromic Acid Pit site is situated in the Hueco Bolson intermontane valley. The Hueco Bolson is a primary source of ground water in the El Paso area. City of El Paso and U.S. Army water-supply wells are located on all sides of the study area and are completed 600 to more than 1,200 feet below land surface. The ground-water level in the area of the Chromic Acid Pit site has declined about 25 feet from 1982 to 1993. Depth to water at the Chromic Acid Pit site in September 1994 was about 284 feet below land surface; ground-water flow is to the southeast. Ground-water samples collected from monitoring wells at the Chromic Acid Pit site contained dissolved-solids concentrations of 442 to 564 milligrams per liter. Nitrate as nitrogen concentrations ranged from 2.1 to 2.7 milligrams per liter; nitrite plus nitrate as nitrogen

  20. Coercive Air Strategy in Post-Cold War Peace Operations

    Science.gov (United States)

    1999-06-01

    Muslim overlords and were supported by Serbia and Montenegro . Russia entered into the conflict on the side of the Christian peasants and crushed the...on Reforming Multilateral Peace Operations. May 1994. Corsini, Roberto . The Balkan War: What Role for Air Power? Maxwell AFB, AL: April 1995. Doyle

  1. Evolution of the Air Component Commander Post Goldwater-Nichols

    Science.gov (United States)

    2013-06-01

    paraphrase noted scientist Charles Darwin , “In the long history of humankind those who learned to collaborate and improvise most effectively have prevailed...3 Moseley, interview. 4 Deptula, interview. 5 Charles Darwin Quotes, http://www.brainyquote.com...Went Wrong, and Why. New York: Forge, 2003. ———. "The St. Mihiel Sailent." Air Force Magazine vol 83 no 2 (February 2000): 74-79. Charles Darwin

  2. Groundwater quality and occurrence and distribution of selected constituents in the Aquia and Upper Patapsco aquifers, Naval Air Station Patuxent River, St. Mary's County, Maryland, July 2008

    Science.gov (United States)

    Dieter, Cheryl A.; Campo, Kimberly W.; Baker, Anna C.

    2012-01-01

    The Naval Air Station Patuxent River in southern Maryland has continued to expand in the first decade of the 21st century, contributing to rapid population growth in the surrounding area. The increase in population has caused State and County water managers and others to be concerned about the impact of population growth on the quantity and quality of groundwater supplies. The U.S. Geological Survey has been investigating the groundwater resources of the air station since 1998. As part of that ongoing investigation, groundwater was sampled in 2008 in six wells in the Aquia aquifer and two wells in the Upper Patapsco aquifer in the vicinity of Naval Air Station Patuxent River and Webster Outlying Field. Groundwater samples were analyzed for basic chemistry (field parameters, major ions, and nutrients) as well as several water-quality issues of concern including the occurrence of arsenic and tungsten, and saltwater intrusion. The results of the 2008 groundwater-quality sampling indicate that the overall quality of groundwater in the Aquia aquifer has not changed since 1943; data are too limited to determine if groundwater quality has changed in the Upper Patapsco aquifer. At one well in the Aquia aquifer, the arsenic concentration exceeded the U.S. Environmental Protection Agency standard for drinking water. Arsenic was not detected in samples from the Upper Patapsco aquifer. Tungsten concentrations were detected at low concentrations near the laboratory reporting level in all eight samples. There was no evidence of saltwater intrusion in any of the wells.

  3. 77 FR 60481 - Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Post-Accident...

    Science.gov (United States)

    2012-10-03

    ... COMMISSION Design, Inspection, and Testing Criteria for Air Filtration and Adsorption Units of Post-Accident..., and Testing Criteria for Air Filtration and Adsorption Units of Post-accident Engineered-Safety... design, inspection, and testing of air filtration and iodine adsorption units of...

  4. Treatment of Perchlorate-Contaminated Groundwater Using Highly-Selective, Regenerable Anion-Exchange Resins at Edwards Air Force Base

    Energy Technology Data Exchange (ETDEWEB)

    Gu, B.

    2003-05-30

    Selective ion exchange is one of the most effective treatment technologies for removing low levels of perchlorate (ClO{sub 4}{sup -}) from contaminated water because of its high efficiency without adverse impacts on the water quality caused by adding or removing any chemicals or nutrients. This report summarizes both the laboratory and a field pilot-scale studies to determine the ability and efficiency of the bifunctional synthetic resins to remove ClO{sub 4}{sup -} from the contaminated groundwater at the Edwards Air Force Base in California. Regeneration of the resins after groundwater treatment was also evaluated using the FeCl{sub 3}-HCl regeneration technique recently developed at Oak Ridge National Laboratory. On the basis of this study, the bifunctional resin, D-3696 was found to be highly selective toward ClO{sub 4}{sup -} and performed much better than one of the best commercial nitrate-selective resins (Purolite A-520E) and more than an order of magnitude better than the Purolite A-500 resin (with a relatively low selectivity). At an influent concentration of {approx} 450 {micro}g/L ClO{sub 4}{sup -} in groundwater, the bifunctional resin bed treated {approx} 40,000 empty bed volumes of groundwater before a significant breakthrough of ClO{sub 4}{sup -} occurred. The presence of relatively high concentrations of chloride and sulfate in site groundwater did not appear to affect the ability of the bifunctional resin to remove ClO{sub 4}{sup -}. However, the presence of high iron or iron oxyhydroxides and/or biomass in groundwater caused a significant fouling of the resin beds and greatly influenced the effectiveness in regenerating the resins sorbed with ClO{sub 4}{sup -}. Under such circumstances, a prefilter ({approx} 0.5-1 {micro}m) was found to be necessary to remove these particulates and to reduce the risk of fouling of the resin beds. Without significant fouling, the resin bed could be effectively regenerated by the FeCl{sub 3} displacement technique

  5. Diesel Subsidies and Yemen Politics: Post-2011 Crises and their Impact on Groundwater Use and Agriculture

    Directory of Open Access Journals (Sweden)

    Adel Al-Weshali

    2015-06-01

    Full Text Available Groundwater is the main source of agricultural and municipal water and contributes 70% of total water use in Yemen. All aquifers are depleting at a very high rate owing to combined effects of a host of socioeconomic, institutional and climate-change factors. The government policy on diesel subsidy was largely believed to be one of the significant factors which stimulated large-scale pumping of water for irrigating water-intensive cash crops such as qat, fruits, and vegetables. A rapid field assessment was conducted between June and December 2011 in six different regions of the country to analyse the impacts of the severe diesel crisis that accompanied the political turmoil of 2011 on groundwater use and agriculture. The study highlighted winners and losers in the process of adapting to diesel shortage and high diesel prices. Farmers’ responses differed according to their social status, financial resources, and farming systems. Poorly endowed households partially or completely abandoned agriculture. Others abandoned farming of irrigated cereals and fodder, but practised deficit irrigation of fruits and vegetables, thus halving the consumption of diesel. Crop yields dropped by 40-60% in all surveyed regions. The intra-governorate transport halt due to the sharp increase in transport cost caused prices at the farm gate to drop. Only those farmers who could absorb increases in diesel prices due to high return:cost ratios, higher drought tolerance, stable prices (qat, and access to alternative sources of water could cope with the diesel crisis.

  6. Autonomic control of post-air-breathing tachycardia in Clarias gariepinus (Teleostei: Clariidae).

    Science.gov (United States)

    Teixeira, Mariana Teodoro; Armelin, Vinicius Araújo; Abe, Augusto Shinya; Rantin, Francisco Tadeu; Florindo, Luiz Henrique

    2015-08-01

    The African catfish (Clarias gariepinus) is a teleost with bimodal respiration that utilizes a paired suprabranchial chamber located in the gill cavity as an air-breathing organ. Like all air-breathing fishes studied to date, the African catfish exhibits pronounced changes in heart rate (f H) that are associated with air-breathing events. We acquired f H, gill-breathing frequency (f G) and air-breathing frequency (f AB) in situations that require or do not require air breathing (during normoxia and hypoxia), and we assessed the autonomic control of post-air-breathing tachycardia using an infusion of the β-adrenergic antagonist propranolol and the muscarinic cholinergic antagonist atropine. During normoxia, C. gariepinus presented low f AB (1.85 ± 0.73 AB h(-1)) and a constant f G (43.16 ± 1.74 breaths min(-1)). During non-critical hypoxia (PO2 = 60 mmHg), f AB in the African catfish increased to 5.42 ± 1.19 AB h(-1) and f G decreased to 39.12 ± 1.58 breaths min(-1). During critical hypoxia (PO2 = 20 mmHg), f AB increased to 7.4 ± 1.39 AB h(-1) and f G decreased to 34.97 ± 1.78 breaths min(-1). These results were expected for a facultative air breather. Each air breath (AB) was followed by a brief but significant tachycardia, which in the critical hypoxia trials, reached a maximum of 143 % of the pre-AB f H values of untreated animals. Pharmacological blockade allowed the calculation of cardiac autonomic tones, which showed that post-AB tachycardia is predominantly regulated by the parasympathetic subdivision of the autonomic nervous system.

  7. Application of LOD Technology in Groundwater Finite Element Post-processing%LOD技术在地下水有限元后处理中的应用

    Institute of Scientific and Technical Information of China (English)

    毕振波; 郑爱勤; 崔振东

    2011-01-01

    地下水有限元后处理阶段的数据量较大,这对模开重现、网络快速传输和计算结果的实时可视化造成困难.为此,分析地下水有限元后处理中面临的主要问题和LOD技术,指出顶点元素删除法是一种适应地下水有限元后处理的有效数据模型简化方法,设计顶点删除和恢复过程中的主要数据结构,并应用DT方法对“空洞”进行局部三角剖分.实例证明该方法在地下水有限元后处理中应用的有效性.%It is difficult for the reproducing, the rapid transmission based on network and the real time visualization of calculated results of finite element models that there is a large amount of data in finite element post-processing stage in groundwater. Therefore, based on analyzing the main problems existing in the post-processing of finite element in groundwater and Level of Detail(LOD) technology, this paper argues that vertex element deletion method is a effective data model simplification techniques adapted for finite element post-processing in groundwater, the main data structures of vertex element deletion and restoring are designed, DT method is used for the local triangulation meshing in the "hole" area. The real implemented example proves the effectiveness of vertex element deletion algorithm applied to finite element post-processing in groundwater.

  8. Post-discharge treatment of air effluents polluted by butyl-mercaptan: role of nitrate radical

    Science.gov (United States)

    Braci, L.; Ognier, S.; Liu, Y. N.; Cavadias, S.

    2011-01-01

    Dry air polluted by butyl-mercaptan was treated in a Dielectric Barrier Discharge (DBD) reactor at atmospheric pressure using air as plasmagene gas in discharge and post-discharge modes. The energy density was varied between 200 to 1300 J/L. To assess the treatment efficiency, the concentrations of buty-mercaptan, total Volatile Organic Compounds (VOCs) and SO2 were determined in the exhaust gas. Whatever the energy density was, the treatment efficiency was better in post-discharge mode. The butyl-mercaptan could be completely eliminated from 400 J/L and SO2 selectivity was always low, below 10%. Measurements of CO, CO2 and total VOCs indicated that 50 to 70% of the reaction products were condensed on the reactor wall in the form of micro-droplets, depending on the energy density. FTIR and XPS techniques were used to characterize the reaction products which were soluble in water. These analyses indicated that the reaction products contain oxygen, nitrogen and sulphur in an oxidized form. A reaction mechanism involving hydrogen abstraction from the -SH bond by the nitrate radical was proposed, pointing out the important role of nitrate radicals NO3 in the reactivity of air flowing post-discharge.

  9. Ex post evidence on environmental taxes: an assessment of the French tax on air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Millock, K. [Centre International de Recherche sur l' Environnement et le Developpement (CIRED-CNRS/EHESS), 94 - Nogent sur Marne (France); Nauges, C. [Institut National de Recherches Agronomiques (INRA-LEERNA), 31 - Toulouse (France)

    2003-09-01

    Empirical evidence evaluating the efficiency of economic instruments is still rare despite significant theoretical advances over the last decades. The purpose of the paper is to evaluate one form of environmental taxation: the French tax on air pollution from 1990-99. While starting out in 1985 as a tax levied only on Sulphur emissions, the tax base was subsequently extended to encompass also emissions of nitrogen oxides (NO{sub x}), hydrochloric acid (HCl), and volatile organic compounds (VOC). The revenues of the French tax on air pollution were earmarked for abatement subsidies and the financing of air quality surveillance. We use a plant-level database on emissions, firm characteristics, taxes paid and subsidies received to evaluate the abatement elasticity with regard to the tax and the subsidies. Our ex post analysis also allows for an evaluation of the distributional impact of the earmarked tax on different industry sectors. (author)

  10. Mercury isotope fractionation during transfer from post-desulfurized seawater to air.

    Science.gov (United States)

    Huang, Shuyuan; Lin, Kunning; Yuan, Dongxing; Gao, Yaqin; Sun, Lumin

    2016-12-15

    Samples of dissolved gaseous mercury (DGM) in the post-desulfurized seawater discharged from a coal-fired power plant together with samples of gaseous elemental mercury (GEM) over the post-desulfurized seawater surface were collected and analyzed to study the mercury isotope fractionation during transfer from post-desulfurized seawater to air. Experimental results showed that when DGM in the seawater was converted to GEM in the air, the δ(202)Hg and Δ(199)Hg values were changed, ranging from -2.98 to -0.04‰ and from -0.31 to 0.64‰, respectively. Aeration played a key role in accelerating the transformation of DGM to GEM, and resulted in light mercury isotopes being more likely to be enriched in the GEM. The ratio Δ(199)Hg/Δ(201)Hg was 1.626 in all samples, suggesting that mercury mass independent fractionation occurred owing to the nuclear volume effect during the transformation. In addition, mass independent fractionation of mercury even isotopes was found in the GEM above the post-desulfurized seawater surface in the aeration pool. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Community perspectives on the risk of indoor air pollution arising from contaminated groundwater.

    Science.gov (United States)

    Johnston, Jill E; Kramer, Amanda J; Gibson, Jacqueline MacDonald

    2015-05-01

    The migration of volatile contaminants into overlying buildings, known as vapor intrusion, is a health concern for people living above contaminated groundwater. As public health and environmental agencies develop protocols to evaluate vapor intrusion exposure, little attention has been paid to the experiences and opinions of communities likely to be affected by vapor intrusion. Using a community-driven research approach and qualitative interviews, we explored community perspectives on the vapor intrusion pathway and the perceived impact on community health and well-being among neighbors living atop a large, shallow-chlorinated solvent plume in San Antonio, TX. Most participants associated vapor intrusion with health risks, expressing concern about the unavoidable and uncontrollable nature of their exposure. Few were satisfied with the responsiveness of public officials. Above all, participants wanted more accurate, transparent information and additional independent scientific investigations. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  12. Ground-water quality, water year 1995, and statistical analysis of ground-water-quality data, water years 1994-95, at the Chromic Acid Pit site, US Army Air Defense Artillery Center and Fort Bliss, El Paso, Texas

    Science.gov (United States)

    Abeyta, Cynthia G.; Roybal, R.G.

    1996-01-01

    The Chromic Acid Pit site is an inactive waste disposal site that is regulated by the Resource Conservation and Recovery Act of 1976. The 2.2-cubic-yard cement-lined pit was operated from 1980 to 1983 by a contractor to the U.S. Army Air Defense Artillery Center and Fort Bliss. The pit, located on the Fort Bliss military reservation in El Paso, Texas, was used for disposal and evaporation of chromic acid waste generated from chrome plating operations. The site was closed in 1989, and the Texas Natural Resources Conservation Commission issued permit number HW-50296 (U.S. Environmental Protection Agency number TX4213720101), which approved and implemented post-closure care for the Chromic Acid Pit site. In accordance with an approved post-closure plan, the U.S. Geological Survey is cooperating with the U.S. Army in monitoring and evaluating ground-water quality at the site. One upgradient ground-water monitoring well (MW1) and two downgradient ground-water monitoring wells (MW2 and MW3), installed adjacent to the chromic acid pit, are monitored on a quarterly basis. Ground-water sampling of these wells by the U.S. Geological Survey began in December 1993. The ground-water level, measured in a production well located approximately 1,700 feet southeast of the Chromic Acid Pit site, has declined about 29.43 feet from 1982 to 1995. Depth to water at the Chromic Acid Pit site in September 1995 was 284.2 to 286.5 feet below land surface; ground-water flow at the water table is assumed to be toward the southeast. Ground-water samples collected from monitoring wells at the Chromic Acid Pit site during water year 1995 contained dissolved- solids concentrations of 481 to 516 milligrams per liter. Total chromium concentrations detected above the laboratory reporting limit ranged from 0.0061 to 0.030 milligram per liter; dissolved chromium concentrations ranged from 0.0040 to 0.010 milligram per liter. Nitrate as nitrogen concentrations ranged from 2.1 to 2.8 milligrams per

  13. Risk for intracranial pressure increase related to enclosed air in post-craniotomy patients during air ambulance transport: a retrospective cohort study with simulation.

    Science.gov (United States)

    Brändström, Helge; Sundelin, Anna; Hoseason, Daniela; Sundström, Nina; Birgander, Richard; Johansson, Göran; Winsö, Ola; Koskinen, Lars-Owe; Haney, Michael

    2017-05-12

    Post-craniotomy intracranial air can be present in patients scheduled for air ambulance transport to their home hospital. We aimed to assess risk for in-flight intracranial pressure (ICP) increases related to observed intracranial air volumes, hypothetical sea level pre-transport ICP, and different potential flight levels and cabin pressures. A cohort of consecutive subdural hematoma evacuation patients from one University Medical Centre was assessed with post-operative intracranial air volume measurements by computed tomography. Intracranial pressure changes related to estimated intracranial air volume effects of changing atmospheric pressure (simulating flight and cabin pressure changes up to 8000 ft) were simulated using an established model for intracranial pressure and volume relations. Approximately one third of the cohort had post-operative intracranial air. Of these, approximately one third had intracranial air volumes less than 11 ml. The simulation estimated that the expected changes in intracranial pressure during 'flight' would not result in intracranial hypertension. For intracranial air volumes above 11 ml, the simulation suggested that it was possible that intracranial hypertension could develop 'inflight' related to cabin pressure drop. Depending on the pre-flight intracranial pressure and air volume, this could occur quite early during the assent phase in the flight profile. DISCUSSION: These findings support the idea that there should be radiographic verification of the presence or absence of intracranial air after craniotomy for patients planned for long distance air transport. Very small amounts of air are clinically inconsequential. Otherwise, air transport with maintained ground-level cabin pressure should be a priority for these patients.

  14. Groundwater cleanup by in-situ sparging. IX. Air channeling model for nonaqueous phase liquid removal

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, D.J.; Norris, R.D.; Clarke, A.N. [Eckenfelder, Inc., Nashville, TN (United States)

    1996-04-01

    A mathematical model is developed to simulate the removal of dissolved and nonaqueous phase liquid (NAPL) volatile organic compounds (VOCs) from contaminated aquifers by sparging. The model assumes that the sparging air moves through the aquifer in persistent channels and that NAPL must dissolve and move to these channels by diffusion and dispersion processes. The dependence of the model results on model parameters is explored, and practical implications for sparging well operation are discussed.

  15. Soil- and groundwater-quality data for petroleum hydrocarbon compounds within Fuels Area C, Ellsworth Air Force Base, South Dakota, 2014

    Science.gov (United States)

    Bender, David A.; Rowe, Barbara L.

    2015-01-01

    Ellsworth Air Force Base is an Air Combat Command located approximately 10 miles northeast of Rapid City, South Dakota. Ellsworth Air Force Base occupies about 6,000 acres within Meade and Pennington Counties, and includes runways, airfield operations, industrial areas, housing, and recreational facilities. Fuels Area C within Ellsworth Air Force Base is a fuels storage area that is used to support the mission of the base. In fall of 2013, the U.S. Geological Survey began a study in cooperation with the U.S. Air Force, Ellsworth Air Force Base, to estimate groundwater-flow direction, select locations for permanent monitoring wells, and install and sample monitoring wells for petroleum hydrocarbon compounds within Fuels Area C. Nine monitoring wells were installed for the study within Fuels Area C during November 4–7, 2014. Soil core samples were collected during installation of eight of the monitoring wells and analyzed for benzene, toluene, ethylbenzene, total xylenes, naphthalene,m- and p-xylene, o-xylene, and gasoline- and diesel-range organic compounds. Groundwater samples were collected from seven of the nine wells (two of the monitoring wells did not contain enough water to sample or were dry) during November 19–21, 2014, and analyzed for select physical properties, benzene, toluene, ethylbenzene, total xylenes, naphthalene, m- and p-xylene, o-xylene, and gasoline- and diesel-range organic compounds. This report describes the nine monitoring well locations and presents the soil- and groundwater-quality data collected in 2014 for this study.

  16. Post-Aire maturation of thymic medullary epithelial cells involves selective expression of keratinocyte-specific autoantigens.

    Science.gov (United States)

    Wang, Xiaoping; Laan, Martti; Bichele, Rudolf; Kisand, Kai; Scott, Hamish S; Peterson, Pärt

    2012-03-01

    The autoimmune regulator (Aire)-directed ectopic expression of tissue-specific antigens (TSAs) by mature medullary thymic epithelial cells (mTECs) has been viewed as an essential mechanism in the induction of central tolerance. Recent data suggest that the survival of mTECs extends beyond the Aire+ cell population to form the post-Aire mTEC population and Hassall's corpuscles (HCs). The nature and function of these post-Aire epithelial cells and structures, however, have remained unidentified. In this study, we characterized in detail the end-stage development of mTECs and HCs in both Aire-sufficient and Airedeficient mice. In addition, using a transgenic mouse model in which the LacZ reporter gene is under the control of the endogenous Aire promoter, we purified and analyzed the post-Aire mTECs to characterize their function. We showed that the end-stage maturation of mTECs closely resembles that of keratinocytes and that the lack of Aire results in a marked block of mTEC differentiation, which is partially overcome by ligands for RANK and CD40. We also provide evidence that, during mTEC development, Aire is expressed only once and during a limited 1-2 day period. The following loss of Aire expression is accompanied by a quick downregulation of MHC class II and CD80, and of most of the Aire-dependent and Aire-independent TSAs, with the exception of keratinocyte-specific genes. In the final stage of maturation, the mTECs lose their nuclei to become HCs and specifically express desmogleins (DGs) 1 and 3, which, via cross-presentation by APCs, may contribute to tolerance against these pemphigus vulgaris-related TSAs.

  17. KAJIAN SPASIAL KUALITAS AIR TANAH BEBAS BERDASARKAN KEDALAM MUKA AIR TANAH: STUDI KASUS DI DATARAN ALUVIAL DAS PEMALI KABUPATEN BREBES (Spatial Study of the Quality of Free Groundwater Based on the Surface Depth of Groundwater at an Alluvial Land

    Directory of Open Access Journals (Sweden)

    Siti Sundari Miswadi

    2009-07-01

    kadarnya melebihi NAB. Kedalaman MAT yang menunjukkan kualitas air cukup baik sesuai analisis adalah pada kedalaman di atas 8,51 meter dan antara 5,80-6,70 meter.   ABSTRACT Most of the alluvial areas of Pemali River Basin (DAS in Brebes district are onion, soybean, cassava, and chili farm production centre. Besides, the area is also known for duck husbandry producing eggs, and it is developed fast. The agriculture and husbandry are mostly met in the residential area, whereas the activities use fertilizer and pesticides and also produce cattle waste which, of course, will contaminate people’s wells. Since the clean water service of the Municipal Waterworks (PDAM has not reach all of the Pemali River Basin (DAS, especially in alluvial residential area, so for cooking, drinking, bathing, washing and other needs, the people make well with various depth, without concerning the right well making and health requirements. The purpose of the research is to map the quality of free ground water based on the depth of water ground surface in the Pemali DAS alluvial area. The method used is analyzing the quality of the free ground water laboratorically, and the result is plotted to 30 sample points in the map of groundwater surface depth divided into 11 classes. The result of the research shows that there are 10 parameters of water quality which content over the Limit Edge Value (NAB, they are, TDS, DHL, Organochlorine, Carbamat, Alkalinity, COD, BOD, Coliform Total, waste Coliform, and pH, whether the NO3-, NO2-, SO4=, Ca2+, phosphate, and muddiness parameter generally have content below NAB in all depth. Seen from some of the sample points which parameter amount has content over the NAB,  the 0.37-3.98 meters ground water surface depth has eight parameters which over the NAB, then 0.10-0.36 meter depth with five parameters, and 3.99-8.50 meters with four parameters which over the NAB. Based on the parameter amount of each sample point, so in 0.37-1.27 meters MAT depth there are

  18. Effects of the Post-Olympics Driving Restrictions on Air Quality in Beijing

    Directory of Open Access Journals (Sweden)

    Hua Ma

    2016-09-01

    Full Text Available To reduce congestion and air pollution, 20% driving restriction, a license plate-based traffic control measure, has been implemented in Beijing since October 2008. While the long-term impacts of this policy remain controversial, it is important to understand how and why the policy effects of driving restrictions change over time. In this paper, the short- and long-run effects of the 20% driving restrictions in Beijing and the key factors shaping the effects are analyzed using daily PM10 pollution data. The results showed that in the short run, 20% driving restriction could effectively reduce ambient PM10 levels. However, this positive effect rapidly faded away within a year due to long-term behavioral responses of residents. A modified 20% restriction, designed to replace the original 20% restriction system since April 2009, which is less stringent and provides more possibility for intertemporal driving substitution, has shown some positive influence on air quality over the long run comparing with that under the original policy design. Temporarily, the more stringent the driving restriction was, the better effects it would have on air quality. In the long-run, however, the policy was likely to cause a vicious circle, and more stringent policy might induce stronger negative incentives which would result in even worse policy effects. Lessons learned from study of the effects of driving restrictions in Beijing will help other major cities in China and abroad to use driving restrictions more prudently and effectively in the future. Decision-makers should carefully consider the pros and cons of a transport policy and conduct the ex-ante and ex-post evaluations on it.

  19. Impact to groundwater resources by landfill foundry industries waste in Tandil, Buenos Aires, Argentina. A preliminary study; Impacto al recurso hidrico subterraneo por vertedero de residuos de industrias de fundicion en Tandil, Buenos Aires, Argentina. Un estudio preliminar

    Energy Technology Data Exchange (ETDEWEB)

    Miguel, R. E.; Ruiz de Galarreta, V. A.; Banda Noriega, R. B.

    2009-07-01

    In Tandil city, in Buenos Aires province, Argentina, the foundry industry is one of the most important production lines. The waste generated by these industries has historically been disposed as fill material in pit quarries and brick works of the likelihood that some of his constituents leach contacting the underground water resources. The aim of this paper is to present the preliminaries results hydrochemical and hydrodynamic study conducted in a landfill of waste foundry industries. The work is around developing a disposal site with the measurement of groundwater levels and taking water samples along an annual hydrological cycle (November 2007 - November 2008). The hydrodynamic analysis shows that the groundwater flow is from the west from a rocky area where high variance across the study area. Hydrochemistry in relation to concentrations of nitrate and electrical conductivity vary significantly upstream and downstream of the landfill. (Author) 9 refs.

  20. Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated groundwater at Beale Air Force Base in California

    Energy Technology Data Exchange (ETDEWEB)

    Bogen, K T; Daniels, J I; Hall, L C

    1999-09-01

    This study was designed to accomplish two objectives. The first was to provide to the US Air Force and the regulatory community quantitative procedures that they might want to consider using for addressing uncertainty and variability in exposure to better characterize potential health risk. Such methods could be used at sites where populations may now or in the future be faced with using groundwater contaminated with low concentrations of the chemical trichloroethylene (TCE). The second was to illustrate and explain the application of these procedures with respect to available data for TCE in ground water beneath an inactive landfill site that is undergoing remediation at Beale Air Force Base in California. The results from this illustration provide more detail than the more traditional conservative deterministic, screening-level calculations of risk, also computed for purposes of comparison. Application of the procedures described in this report can lead to more reasonable and equitable risk-acceptability criteria for potentially exposed populations at specific sites.

  1. Mining Environmental Data from a Coupled Modelling System to Examine the Impact of Agricultural Management Practices on Groundwater and Air Quality

    Science.gov (United States)

    Garcia, V.; Cooter, E. J.; Hayes, B.; Murphy, M. S.; Bash, J. O.

    2014-12-01

    Excess nitrogen (N) resulting from current agricultural management practices can leach into sources of drinking water as nitrate, increasing human health risks of 'blue baby syndrome', hypertension, and some cancers and birth defects. Nitrogen also enters the atmosphere from land surfaces forming air pollution increasing human health risks of pulmonary and cardio-vascular disease. Characterizing and attributing nitrogen from agricultural management practices is difficult due to the complex and inter-related chemical and biological reactions associated with the nitrogen cascade. Coupled physical process-based models, however, present new opportunities to investigate relationships among environmental variables on new scales; particularly because they link emission sources with meteorology and the pollutant concentration ultimately found in the environment. In this study, we applied a coupled meteorology (NOAA-WRF), agricultural (USDA-EPIC) and air quality modelling system (EPA-CMAQ) to examine the impact of nitrogen inputs from corn production on ecosystem and human health and wellbeing. The coupled system accounts for the nitrogen flux between the land surface and air, and the soil surface and groundwater, providing a unique opportunity to examine the effect of management practices such as type and timing of fertilization, tilling and irrigation on both groundwater and air quality across the conterminous US. In conducting the study, we first determined expected relationships based on literature searches and then identified model variables as direct or surrogate variables. We performed extensive and methodical multi-variate regression modelling and variable selection to examine associations between agricultural management practices and environmental condition. We then applied the regression model to predict and contrast pollution levels between two corn production scenarios (Figure 1). Finally, we applied published health functions (e.g., spina bifida and cardio

  2. Wet deposition of air pollution at southwest monsoon outbreak and its impact on groundwater resources of Greater Kochi region

    Digital Repository Service at National Institute of Oceanography (India)

    Joseph, T.; Nair, M.; Balachandran, K.K.; Nair, K.K.C.

    the industrial impact; the possibility of nutrient enriched rainwater peeping into groundwater seems to be a reality. The PO sub(4) and NH sub(4) levels remained high at refinery and fertilizer complex. The enriching effect of PO sub(4) by emissions declines...

  3. Post-discharge treatment of air effluents polluted by butyl-mercaptan: the role of nitrate radical

    Science.gov (United States)

    Liu, Y. N.; Braci, L.; Cavadias, S.; Ognier, S.

    2011-03-01

    Dry air polluted by butyl-mercaptan was treated in a dielectric barrier discharge reactor at atmospheric pressure using air as plasmagene gas in discharge and post-discharge modes. The energy density was varied between 200 and 1300 J l-1. To assess the treatment efficiency, the concentrations of butyl-mercaptan, total volatile organic compounds (VOCs) and SO2 were determined in the exhaust gas. Whatever the energy density was, the treatment efficiency was better in the post-discharge mode. Butyl-mercaptan could be completely eliminated from 400 J l-1 and SO2 selectivity was always low, below 10%. Measurements of CO, CO2 and total VOCs indicated that 50-70% of the reaction products were condensed on the reactor wall in the form of micro-droplets, depending on the energy density. FTIR and XPS techniques were used to characterize the reaction products which were soluble in water. These analyses indicated that the reaction products contained oxygen, nitrogen and sulfur in an oxidized form. A reaction mechanism involving hydrogen abstraction from the -SH bond by the nitrate radical was proposed, pointing out the important role of nitrate radicals NO3 in the reactivity of air flowing post-discharge.

  4. Post-filamentation propagation of high-power laser pulses in air in the regime of narrowly focused light channels

    Science.gov (United States)

    Geints, Yu. E.; Zemlyanov, A. A.; Ionin, A. A.; Mokrousova, D. V.; Seleznev, L. V.; Sinitsyn, D. V.; Sunchugasheva, E. S.

    2016-11-01

    We report the results of experimental and theoretical studies of the post-filamentation stage of nonlinear propagation of high-power pulsed radiation from a Ti : sapphire laser in air. We have for the first time obtained the experimental dependences of the angular divergence of specific spatially localised high-intensity light structures that are observed in the beam after its multiple filamentation (post-filamentation of channels) when varying the initial focusing of laser radiation and its energy. It is found that the angular divergence of the post-filamentation channels decreases with increasing pulse energy and reducing beam numerical aperture. The experimental dependences are qualitatively interpreted based on the diffraction model of the Bessel - Gaussian beam.

  5. The availability of unmanned air vehicles: a post-case study

    NARCIS (Netherlands)

    Smith, M.A.J.; Dekker, R.; Kos, J.; Hontelez, J.A.M.

    2001-01-01

    An Unmanned Air Vehicle (UAV) is an unmanned, remotely controlled, small air vehicle. It has an important role in antisurface warfare. This implies over-the-horizon detection, classification, targeting and battle damage assessment. To perform these tasks several UAVs are needed to assist or

  6. Enhancement of corrosion resistance for plasma nitrided AISI 4140 steel by plain air plasma post-oxidizing

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jiqiang; Liu, Han; Ye, Xuemei [Jiangsu Key Laboratory of Materials Surface Technology, Changzhou University, Changzhou 213164 (China); Chai, Yating [Materials Research and Education Center, Auburn University, AL 36849 (United States); Hu, Jing, E-mail: jinghoo@126.com [Jiangsu Key Laboratory of Materials Surface Technology, Changzhou University, Changzhou 213164 (China); Materials Research and Education Center, Auburn University, AL 36849 (United States)

    2015-05-25

    Highlights: • Plain air was primarily used for plasma post-oxidation for AISI 4140 steel. • A thin iron oxide layer composed of Fe{sub 3}O{sub 4} to Fe{sub 2}O{sub 3} was formed on top of the compound layer. • The ratio of Fe{sub 3}O{sub 4} to Fe{sub 2}O{sub 3} was closely related to the post-oxidizing conditions. • Post-oxidizing at 673 K for 60 min brought out highest ratio of Fe{sub 3}O{sub 4} to Fe{sub 2}O{sub 3} and optimum corrosion resistance. - Abstract: Plasma post-oxidizing was conducted immediately after plasma nitriding in the same equipment for AISI 4140 steel, and plain air was used as the oxygen bearing gas. The cross-sectional microstructures of the treated samples were observed by optical metallography and scanning electron microcopy (SEM), and the thickness of compound layer was measured accordingly. The phases were determined by X-ray diffraction (XRD), corrosion resistance was evaluated by electrochemical polarization, and the surface morphology before and after polarization test was also observed by SEM. Meanwhile, standard Gibbs free energy of the oxidation reactions existed in Fe–O system was calculated. The results show that a thin iron oxide layer composed of magnetite (Fe{sub 3}O{sub 4}) and hematite (Fe{sub 2}O{sub 3}) is formed on top of the compound layer during plasma post-oxidizing process, and the ratio of magnetite (Fe{sub 3}O{sub 4}) to hematite (Fe{sub 2}O{sub 3}) is depended on plasma post-oxidizing temperature and time. Highest ratio of Fe{sub 3}O{sub 4} to Fe{sub 2}O{sub 3} is obtained while post-oxidizing at 673 K for 60 min due to lower standard Gibbs free energy and appropriate forming rate for the formation of Fe{sub 3}O{sub 4} at this temperature. The thin oxide layer brings out significant enhancement of corrosion resistance, especially at higher ratios of Fe{sub 3}O{sub 4} to Fe{sub 2}O{sub 3}, due to the dense and adherent characteristic of Fe{sub 3}O{sub 4} oxide. Surface images of the post-oxidizing specimen

  7. "Lytic" lesions in autologous bone grafts: demonstration of medullary air pockets on post mortem computed tomography.

    Science.gov (United States)

    Rotman, A; Hamilton, K; O'Donnell, C

    2007-12-01

    Donor bone grafts are an important aspect of orthopaedic surgery. The use of plain film as a pathological screening tool before donor bone dispatch has revealed "lytic" lesions in proximal humeri. Donor demographics did not support the diagnosis of myeloma and subsequent computed tomography (CT) scans of these bones identified the lesions as air, not pathology. In total, 27 long bones were scanned and 100% (27/27 cases) exhibited air within the trabecular bone. Three distinct patterns were found: ovoid, linear/branching, and broad channel. A longitudinal course of CT scans was performed to identify at which stage air appeared within the bone. Pre-retrieval, preprocessing, and postprocessing scans revealed that air originated between the retrieval and preprocessing stages of donor bone preparation. There may be multiple aetiology of this phenomenon, including bone retrieval and natural decomposition.

  8. Lineage tracing and cell ablation identify a post-Aire-expressing thymic epithelial cell population.

    Science.gov (United States)

    Metzger, Todd C; Khan, Imran S; Gardner, James M; Mouchess, Maria L; Johannes, Kellsey P; Krawisz, Anna K; Skrzypczynska, Katarzyna M; Anderson, Mark S

    2013-10-17

    Thymic epithelial cells in the medulla (mTECs) play a critical role in enforcing central tolerance through expression and presentation of tissue-specific antigens (TSAs) and deletion of autoreactive thymocytes. TSA expression requires autoimmune regulator (Aire), a transcriptional activator present in a subset of mTECs characterized by high CD80 and major histocompatibility complex II expression and a lack of potential for differentiation or proliferation. Here, using an Aire-DTR transgenic line, we show that short-term ablation specifically targets Aire(+) mTECs, which quickly undergo RANK-dependent recovery. Repeated ablation also affects Aire(-) mTECs, and using an inducible Aire-Cre fate-mapping system, we find that this results from the loss of a subset of mTECs that showed prior expression of Aire, maintains intermediate TSA expression, and preferentially migrates toward the center of the medulla. These results clearly identify a distinct stage of mTEC development and underscore the diversity of mTECs that play a key role in maintaining tolerance. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Formation of the U.S. Air Force Aviator Post Traumatic Stress Disorder Study Group

    Science.gov (United States)

    2016-11-15

    ABSTRACT The first aviator mental health study groups (post-traumatic stress disorder (PTSD) and antidepressants) were approved by the Chief of Aerospace...mental health study groups (post-traumatic stress disorder (PTSD) and antidepressants) were approved by the Chief of Aerospace Medicine for the...traffic controllers were now required to meet enhanced medical standards similar to traditional aircrew such as pilots, navigators, and loadmasters. In

  10. Innovative conditioning of groundwater as a prerequisite for an efficient air-conditioning of buildings by means of near-surface geothermal energy; Innovative Grundwasseraufbereitung als Voraussetzung fuer eine effiziente Gebaeudeklimatisierung durch die Nutzung oberflaechennaher Geothermie

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, C.; Krauss, M.; Steinmetz, H. [Stuttgart Univ. (Germany). Inst. fuer Siedlungswasserbau-, Wasserguete- und Abfallwirtschaft; Edel, H.G.; Kellner, C. [Zueblin Umwelttechnik GmbH (Germany)

    2012-10-16

    The air-conditioning of buildings increasingly requires alternatives to cover the energy demand from renewable energy sources. One possibility consists of the utilization of a heat pump fed with ground water. Due to the local hydrogeochemical realities, groundwater however contains large amounts of solved iron and manganese resulting in operational problems (depositions) in plant sections. Without a previous conditioning, such waters cannot be utilized. Under this aspect, the authors of the contribution under consideration report on the technology of an in-situ conditioning of groundwater as an innovative conditioning process to remove iron and manganese enabling an efficient air-conditioning of buildings by utilizing sub-surface geothermal energy (groundwater). The process is characterized by numerous advantages such as the absence of residues from processing residues compared with conventional conditioning procedures. Beside the description of the procedure, plant engineering as well as the planning fundamentals, the authors of the contribution under consideration present the in-situ-conditioning of groundwater for the air-conditioning of the buildings of the Berufsakademie Hohenheim (Baden-Wueerttemberg, Federal Republic of Germany) as a case study.

  11. Results of soil, ground-water, surface-water, and streambed-sediment sampling at Air Force Plane 85, Columbus, Ohio, 1996

    Science.gov (United States)

    Parnell, J.M.

    1997-01-01

    The U.S. Geological Survey (USGS), in cooperation with Aeronautical Systems Center, Environmental Management Directorate, Restoration Division, prepared the Surface- and Ground- Water Monitoring Work Plan for Air Force Plant 85 (AFP 85 or Plant), Columbus, Ohio, under the Air Force Installation Restoration Program to characterize any ground-water, surface-water, and soil contamination that may exist at AFP 85. The USGS began the study in November 1996. The Plant was divided into nine sampling areas, which included some previously investi gated study sites. The investigation activities included the collection and presentation of data taken during drilling and water-quality sampling. Data collection focused on the saturated and unsatur ated zones and surface water. Twenty-three soil borings were completed. Ten monitoring wells (six existing wells and four newly constructed monitoring wells) were selected for water-quality sam pling. Surface-water and streambed-sediment sampling locations were chosen to monitor flow onto and off of the Plant. Seven sites were sampled for both surface-water and streambed-sediment quality. This report presents data on the selected inorganic and organic constituents in soil, ground water, surface water, and streambed sediments at AFP 85. The methods of data collection and anal ysis also are included. Knowledge of the geologic and hydrologic setting could aid Aeronautical Systems Center, Environmental Management Directorate, Restoration Division, and its governing regulatory agencies in future remediation studies.

  12. Lineage Tracing and Cell Ablation Identify a Post-Aire-Expressing Thymic Epithelial Cell Population

    Directory of Open Access Journals (Sweden)

    Todd C. Metzger

    2013-10-01

    Full Text Available Thymic epithelial cells in the medulla (mTECs play a critical role in enforcing central tolerance through expression and presentation of tissue-specific antigens (TSAs and deletion of autoreactive thymocytes. TSA expression requires autoimmune regulator (Aire, a transcriptional activator present in a subset of mTECs characterized by high CD80 and major histocompatibility complex II expression and a lack of potential for differentiation or proliferation. Here, using an Aire-DTR transgenic line, we show that short-term ablation specifically targets Aire+ mTECs, which quickly undergo RANK-dependent recovery. Repeated ablation also affects Aire− mTECs, and using an inducible Aire-Cre fate-mapping system, we find that this results from the loss of a subset of mTECs that showed prior expression of Aire, maintains intermediate TSA expression, and preferentially migrates toward the center of the medulla. These results clearly identify a distinct stage of mTEC development and underscore the diversity of mTECs that play a key role in maintaining tolerance.

  13. Lineage tracing and cell ablation identifies a post-Aire expressing thymic epithelial cell population

    Science.gov (United States)

    Metzger, Todd C.; Khan, Imran S.; Gardner, James M.; Mouchess, Maria L.; Johannes, Kellsey P.; Krawisz, Anna K.; Skrzypczynska, Katarzyna M.; Anderson, Mark S.

    2013-01-01

    Thymic epithelial cells in the medulla (mTECs) play a critical role in enforcing central tolerance through expression and presentation of tissue-specific antigens (TSAs) and deletion of autoreactive thymocytes. TSA expression requires autoimmune regulator (Aire), a transcriptional activator present in a subset of mTECs characterized by high CD80 and MHC II expression and a lack of potential for differentiation or proliferation. Here, using an Aire-DTR transgenic line, we show that short-term ablation specifically targets Aire+ mTECs, which quickly undergo RANK-dependent recovery. Repeated ablation also affects Aire− mTECs, and using an inducible Aire-Cre fate-mapping system, we find that this results from the loss of a subset of mTECs that showed prior expression of Aire, maintains intermediate TSA expression, and preferentially migrates towards the center of the medulla. These results clearly identify a distinct stage of mTEC development and underscore the diversity of mTECs that play a key role in maintaining tolerance. PMID:24095736

  14. Groundwater cleanup by in-situ sparging. XIII. Random air channels for sparing of dissolved and nonaqueous phase volatiles

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, D.J.; Clarke, A.N. [Eckenfelder, Inc., Nashville, TN (United States); Kaminski, K.M.; Chang, E.Y. [Martin Luther King Magnet High School, Nashville, TN (United States)

    1997-12-01

    A mathematical model is developed to simulate the sparging of dissolved volatile organic compounds (VOCs) and nonaqueous phase liquid (NAPL) from contaminated aquifers. The sparging air moves through the aquifer in persistent, random channels, to which VOC must move by diffusion/dispersion to be removed. The dependence of the rate of remediation on the various model parameters is investigated and some practical conclusions are reached regarding the operation of air sparging wells for aquifer remediation. VOCs of low water solubility (such as alkanes) and present as NAPL are found to be removed by air sparging much more slowly than VOCs of higher water solubility (such as benzene, toluene, ethylbenzene and xylenes) and present as NAPL, due to the very small maximum concentration gradients which can be maintained around droplets of the former. These small concentration gradients result in very slow rates of NAPL solution.

  15. Ground-water levels and water-quality data for wells in the Spring Creek area near Arnold Air Force Base, Tennessee, April and May 2000

    Science.gov (United States)

    Williams, Shannon D.; Aycock, Robert A.

    2001-01-01

    Arnold Air Force Base (AAFB) occupies about 40,000 acres in Coffee and Franklin Counties, Tennessee. Numerous site-specific ground-water contamination investigations have been conducted at designated solid waste management units (SWMU?s) at AAFB. Several synthetic volatile organic compounds (VOC?s), primarily chlorinated solvents, have been identified in groundwater samples collected from monitoring wells near SWMU 8 in the Spring Creek area. During April and May 2000, a study of the groundwater resources in the Spring Creek area was conducted to determine if VOC?s from AAFB have affected local private water supplies and to advance understanding of the ground-water-flow system in this area. The study focused on sampling private wells located within the Spring Creek area that are used as a source of drinking water. Ground-water-flow directions were determined by measuring water levels in wells and constructing a potentiometric-surface map of the Manchester aquifer in the study area. Data were collected from a total of 35 private wells and 22 monitoring wells during the period of study. Depths to ground water were determined for 22 of the private wells and all 22 of the monitoring wells. The wells ranged in depth from 21 to 105 feet. Water-level altitudes ranged from 930 to 1,062 feet above sea level. Depths to water ranged from 8 to 83 feet below land surface. Water-quality samples were collected from 29 private wells which draw water from either gravel zones in the upper part of the Manchester aquifer, fractured bedrock in the lower part of the Manchester aquifer, or a combination of these two zones. Concentrations of 50 of the 55 VOC?s analyzed for were less than method detection limits. Chloroform, acetone, chloromethane, 2-butanone, and tetrachloroethylene were detected in concentrations exceeding the method detection limits. Only chloroform and acetone were detected in concentrations equal to or exceeding reporting limits. Chloroform was detected in a sample

  16. Fate of Stream-Evaded CO2 in Relation to Air Drainage Patterns in a BC Coastal Douglas-Fir Forest During Pre- and Post-Harvest Periods

    Science.gov (United States)

    Johnson, M. S.; Hawthorne, I.; Black, T.; Jassal, R. S.

    2011-12-01

    directions were strongly katabatic, suggesting evaded CO2 from the stream was advecting down gradient and away from the EC flux tower. Under these conditions, stream-evaded CO2 would not be detected by the EC tower. During pre-harvest summer months, nighttime airflows remained down gradient (e.g. katabatic cold-air drainage), while daytime airflows for summer months exhibited anabatic and katabatic conditions, suggesting some stream-evaded CO2 was directed back into the tower footprint during summer days. During post-harvest months, nocturnal airflows remained katabatic and away from the tower. Post-harvest summer daytime airflows were less organized compared with pre-harvest conditions, with a more pronounced anabatic pattern that likely transports stream-evaded CO2 back towards the EC tower footprint throughout summer days. Overall, airflows were predominantly down-gradient and away from the EC tower, suggesting that a large fraction of stream-evaded CO2 from the stream was not detected by the EC system.

  17. Air Pollution Technology: A Suggested Two-Year Post High School Curriculum.

    Science.gov (United States)

    Santa Fe Community Coll., Gainesville, FL.

    The purpose of this guide is to help school administrators and instructors in planning and developing new programs in the air pollution control field, or in evaluating those in existence. It contains course outlines for technical specialization courses as well as necessary basic science and communication courses. Also included are plans for…

  18. Simulation of Thermal and Chemical Relaxation in a Post-Discharge Air Corona Reactor

    CERN Document Server

    Meziane, M; Ducasse, O; Yousfi, M

    2016-01-01

    In a DC point-to-plane corona discharge reactor, the mono filamentary streamers cross the inter electrode gap with a natural repetition frequency of some tens of kHz. The discharge phase (including the primary and the secondary streamers development) lasts only some hundred of nanoseconds while the post-discharge phases occurring between two successive discharge phases last some tens of microseconds. From the point of view of chemical activation, the discharge phases create radical and excited species located inside the very thin discharge filaments while during the post-discharge phases these radical and excited species induce a chemical kinetics that diffuse in a part of the reactor volume. From the point of view of hydrodynamics activation, the discharge phases induce thermal shock waves and the storage of vibrational energy which relaxes into thermal form only during the post-discharge phase. Furthermore, the glow corona discharges that persist during the post-discharge phases induce the so called electri...

  19. Groundwater cleanup by in-situ sparging. X. Air channeling model for biosparging of nonaqueous phase liquid

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, D.J.; Norris, R.D.; Clarke, A.N. [Eckenfelder Inc., Nashville, TN (United States)

    1996-06-01

    A column model is developed to simulate the removal and biodegradation of dissolved and nonaqueous phase liquid (NAPL) volatile organic compounds (VOCs) from contaminated aquifers by biosparging. The model assumes that the injected air moves through the aquifer in persistent channels and that NAPL must dissolve and move to these channels by diffusion and dispersion. The dependence of model results on several of the parameters of the model is investigated, and suggestions for optimizing biosparging system operations are made. The removal of NAPL VOCs of quite low solubility (such as alkanes) from smear zones below the water is modeled, and is found to be an extremely slow process. Drawing down the water table to below the smear zone by pumping is suggested as a possible solution.

  20. An analysis of post-traumatic stress symptoms in United States Air Force drone operators.

    Science.gov (United States)

    Chappelle, Wayne; Goodman, Tanya; Reardon, Laura; Thompson, William

    2014-06-01

    Remotely piloted aircraft (RPA), commonly referred to as "drones," have emerged over the past decade as an innovative warfighting tool. Given there is a paucity of empirical research assessing drone operators, the purpose of this study was to assess for the prevalence of PTSD symptoms among this cohort. Of the 1084 United States Air Force (USAF) drone operators that participated, a total of 4.3% endorsed a pattern of symptoms of moderate to extreme level of severity meeting criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders-4th edition. The incidence of PTSD among USAF drone operators in this study was lower than rates of PTSD (10-18%) among military personnel returning from deployment but higher than incidence rates (less than 1%) of USAF drone operators reported in electronic medical records. Although low PTSD rates may be promising, limitations to this study are discussed.

  1. Symptoms of psychological distress and post-traumatic stress disorder in United States Air Force "drone" operators.

    Science.gov (United States)

    Chappelle, Wayne L; McDonald, Kent D; Prince, Lillian; Goodman, Tanya; Ray-Sannerud, Bobbie N; Thompson, William

    2014-08-01

    The goal of this study is to repeat a survey administered in 2010 to assess for changes in mental health among United States Air Force aircrew operating Predator/Reaper remotely piloted aircraft, also commonly referred to as "drones." Participants were assessed for self-reported sources of occupational stress, levels of clinical distress using the Outcome Questionnaire-45.2, and symptoms of post-traumatic stress disorder (PTSD) using the PTSD Checklist-Military Version. A total of 1,094 aircrew responded to the web-based survey composed of the commercially available standardized instruments mentioned above. The survey also contained nonstandardized items asking participants to report the main sources of their occupational stress, as well as questions addressing demographics and work-related characteristics. The estimated response rate to the survey was 49%. Study results reveal the most problematic self-reported stressors are operational: low manning, extra duties/administrative tasks, rotating shift work, and long hours. The results also reveal 10.72% of operators self-reported experiencing high levels of distress and 1.57% reported high levels of PTSD symptomology. The results are lower than findings from the 2010 survey and from soldiers returning from Iraq and Afghanistan. Implications of the study and recommendations for United States Air Force line leadership and mental health providers are discussed.

  2. Air quality monitoring of the post-operative recovery room and locations surrounding operating theaters in a medical center in Taiwan.

    Science.gov (United States)

    Tang, Chin-Sheng; Wan, Gwo-Hwa

    2013-01-01

    To prevent surgical site infection (SSI), the airborne microbial concentration in operating theaters must be reduced. The air quality in operating theaters and nearby areas is also important to healthcare workers. Therefore, this study assessed air quality in the post-operative recovery room, locations surrounding the operating theater area, and operating theaters in a medical center. Temperature, relative humidity (RH), and carbon dioxide (CO2), suspended particulate matter (PM), and bacterial concentrations were monitored weekly over one year. Measurement results reveal clear differences in air quality in different operating theater areas. The post-operative recovery room had significantly higher CO2 and bacterial concentrations than other locations. Bacillus spp., Micrococcus spp., and Staphylococcus spp. bacteria often existed in the operating theater area. Furthermore, Acinetobacter spp. was the main pathogen in the post-operative recovery room (18%) and traumatic surgery room (8%). The mixed effect models reveal a strong correlation between number of people in a space and high CO2 concentration after adjusting for sampling locations. In conclusion, air quality in the post-operative recovery room and operating theaters warrants attention, and merits long-term surveillance to protect both surgical patients and healthcare workers.

  3. Air quality monitoring of the post-operative recovery room and locations surrounding operating theaters in a medical center in Taiwan.

    Directory of Open Access Journals (Sweden)

    Chin-Sheng Tang

    Full Text Available To prevent surgical site infection (SSI, the airborne microbial concentration in operating theaters must be reduced. The air quality in operating theaters and nearby areas is also important to healthcare workers. Therefore, this study assessed air quality in the post-operative recovery room, locations surrounding the operating theater area, and operating theaters in a medical center. Temperature, relative humidity (RH, and carbon dioxide (CO2, suspended particulate matter (PM, and bacterial concentrations were monitored weekly over one year. Measurement results reveal clear differences in air quality in different operating theater areas. The post-operative recovery room had significantly higher CO2 and bacterial concentrations than other locations. Bacillus spp., Micrococcus spp., and Staphylococcus spp. bacteria often existed in the operating theater area. Furthermore, Acinetobacter spp. was the main pathogen in the post-operative recovery room (18% and traumatic surgery room (8%. The mixed effect models reveal a strong correlation between number of people in a space and high CO2 concentration after adjusting for sampling locations. In conclusion, air quality in the post-operative recovery room and operating theaters warrants attention, and merits long-term surveillance to protect both surgical patients and healthcare workers.

  4. Air Quality Monitoring of the Post-Operative Recovery Room and Locations Surrounding Operating Theaters in a Medical Center in Taiwan

    Science.gov (United States)

    Tang, Chin-Sheng; Wan, Gwo-Hwa

    2013-01-01

    To prevent surgical site infection (SSI), the airborne microbial concentration in operating theaters must be reduced. The air quality in operating theaters and nearby areas is also important to healthcare workers. Therefore, this study assessed air quality in the post-operative recovery room, locations surrounding the operating theater area, and operating theaters in a medical center. Temperature, relative humidity (RH), and carbon dioxide (CO2), suspended particulate matter (PM), and bacterial concentrations were monitored weekly over one year. Measurement results reveal clear differences in air quality in different operating theater areas. The post-operative recovery room had significantly higher CO2 and bacterial concentrations than other locations. Bacillus spp., Micrococcus spp., and Staphylococcus spp. bacteria often existed in the operating theater area. Furthermore, Acinetobacter spp. was the main pathogen in the post-operative recovery room (18%) and traumatic surgery room (8%). The mixed effect models reveal a strong correlation between number of people in a space and high CO2 concentration after adjusting for sampling locations. In conclusion, air quality in the post-operative recovery room and operating theaters warrants attention, and merits long-term surveillance to protect both surgical patients and healthcare workers. PMID:23573296

  5. Post-coring entrapment of modern air in polar ice cores collected near the firn-ice transition: evidence from CFC-12 measurements in Antarctic firn air and shallow ice cores

    Directory of Open Access Journals (Sweden)

    M. Aydin

    2010-01-01

    Full Text Available In this study, we report the first measurements of CFC-12 (CCl2F2 in air extracted from shallow ice cores along with firn air CFC-12 measurements from three Antarctic sites. The firn air data are consistent with the known atmospheric history of CFC-12. In contrast, the ice core samples collected near the firn-ice transition exhibit anomalously high CFC-12 levels. Together, the ice core and firn air data provide evidence for presence of modern air entrapped in shallow ice core samples. We propose that this is due to closure of open pores after drilling, entrapping modern air and resulting in elevated CFC-12 mixing ratios. Our measurements reveal the presence of open porosity below the depth at which firn air samples can be collected and demonstrate how the composition of bubble air in shallow ice cores can be altered during the post-drilling period through purely physical processes. These results have implications for investigations involving trace gas composition of bubbles in shallow ice cores.

  6. Post-coring entrapment of modern air in some shallow ice cores collected near the firn-ice transition: evidence from CFC-12 measurements in Antarctic firn air and ice cores

    Directory of Open Access Journals (Sweden)

    M. Aydin

    2010-06-01

    Full Text Available In this study, we report measurements of CFC-12 (CCl2F2 in firn air and in air extracted from shallow ice cores from three Antarctic sites. The firn air data are consistent with the known atmospheric history of CFC-12. In contrast, some of the ice core samples collected near the firn-ice transition exhibit anomalously high CFC-12 levels. Together, the ice core and firn air data provide evidence for the presence of modern air entrapped in the shallow ice core samples that likely contained open pores at the time of collection. We propose that this is due to closure of the open pores after drilling, entrapping modern air and resulting in elevated CFC-12 mixing ratios. Our results reveal that open porosity can exist below the maximum depth at which firn air samples can be collected, particularly at sites with lower accumulation rates. CFC-12 measurements demonstrate that post-drilling closure of open pores can lead to a change in the composition of bubble air in shallow ice cores through purely physical processes. The results have implications for investigations involving trace gas composition of bubbles in shallow ice cores collected near the firn-ice transition.

  7. Inter-comparison of NPP/CrIS radiances with VIIRS, AIRS, and IASI: a post-launch calibration assessment

    Science.gov (United States)

    Wang, Likun; Han, Yong; Tremblay, Denis; Weng, Fuzhong; Goldberg, Mitchell

    2012-11-01

    The Cross-track Infrared Sounder (CrIS) on the newly-launched Suomi National Polar-orbiting Partnership (Suomi NPP) is a Fourier transform spectrometer that provides soundings of the atmosphere with 1305 spectral channels, over 3 wavelength ranges: LWIR (9.14 - 15.38 μm) MWIR (5.71 - 8.26 μm) and SWIR (3.92 - 4.64 μm). An accurate spectral and radiometric calibration as well as geolocation is fundamental for CrIS radiance Sensor Data Records (SDRs). In this study, through inter- and intra-satellite calibration efforts, we focus on assessment of NPP/CrIS post-launch performance. First, we compare CrIS hyperspectral radiance measurements with the Atmospheric Infrared Sounder (AIRS) on NASA Earth Observing System (EOS) Aqua and Infrared Atmospheric Sounding Interferometer (IASI) on Metop-A to examine spectral and radiometric consistence and difference among three hyperspectral IR sounders. Secondly, an accurate collocation algorithm has been developed to collocate high spatial resolution measurements from the Visible Infrared Imager Radiometer Suite (VIIRS) within each CrIS Field of View (FOV). We compare CrIS spectrally-averaged radiances with the spatially-averaged and collocated pixels from the VIIRS IR channels. Since CrIS and VIIRS are onboard on the same satellite platform, the intra-satellite comparison will allow examining the radiometric difference between CrIS and VIIRS with scene temperatures, scan angles, and orbital position. In addition, given a high spatial resolution of VIIRS channels, the VIIRS-CrIS comparison results can access geolocation accuracy of CrIS that have relatively large FOVs (14 km at ndair) using high resolution VIIRS pixel (375m or 750m at nadir).

  8. groundwater contribution to crop water requirement groundwater ...

    African Journals Online (AJOL)

    eobe

    Keywords: Groundwater, water table, capillary rise, soil type, waterleaf, ... GROUNDWATER CONTRIBUTION TO WATERLEAF (TALINUM TRIANGULARE) IN OXISOLS, I. J. ... Nutritionally, ... information to facilitate increased crop production,.

  9. Research on the Effect of Well Completion Technology of Ground Temperature Air-Conditioner Project on Groundwater System%地温空调成井工艺参数对地下水系统的影响

    Institute of Scientific and Technical Information of China (English)

    米庆彬; 付博; 窦明; 韩涛; 张彦; 张坤; 张华云

    2014-01-01

    在对成井环节分析的基础上,识别了对地下水系统影响较为显著的成井工艺参数(即井径和滤水管孔隙率),基于地下水水热运移基本原理,建立了地下水流动和热量输运耦合模型。选取典型地温空调项目,通过设计不同成井工艺参数,模拟地温空调运行对地下水流场和温度场的影响。结果显示:不同井径和孔隙率在地温空调运行中,对地下水系统影响程度差别较大,井径对抽水井、回水井的影响比较明显,孔隙率对抽水井的影响大于对回水井的影响,适合安阳市地温空调的井径为30 cm、滤水管孔隙率为30%。%According to the analysis of well completion process,this paper distinguished that the well completion tech-parameters (well diameter and filter porosity)could largely affect the groundwater system. Based on the fundamental principle of water and heat transfer,the coupling model of the flow of groundwater and the transport of heat was established. It selected several typical ground temperature air-conditioning projects in order to simulate the effect of ground temperature air-conditioning to the underground flow field and temperature field by design well completion technolo-gies with different parameters. From the results of simulation,it finds out that the different well diameter and filter porosity can make a great differ-ence on the effect of groundwater system. The well diameter can affect the pumping wells and recharge wells obviously,on another hand,the filter porosity parameter’s effect on the pumping wells is bigger than on recharge wells. It finds out that 30cm of well diameter and 30% of the porosity of filter are more suitable for the ground temperature air-conditioning project in Anyang City.

  10. The Quest for Relevant Air Power: Continental European Responses to the Air Power Challenges of the Post-Cold War Era

    Science.gov (United States)

    2011-08-01

    aérienne aux conflits contemporains” [The adjustment of the air arm in contemporary conflicts] (Paris, 1984), “Histoire de la guerre aérienne” [History...analyse it in its entire depth, and even to present alternative sug- gestions to the “absolutes” stated in the SwAF’s formal doctrine.172 Since the

  11. Integrated Field-Scale, Lab-Scale, and Modeling Studies for Improving the Ability to Assess the Groundwater to Indoor Air Pathway at Chlorinated Solvent-Impacted Groundwater Sites

    Science.gov (United States)

    2012-08-01

    16 Soil Gas Monitoring of SF6 ...Radon soil gas concentration contours [pCi/L] ...........................................................15 Figure 13. SF6 in indoor air with a constant...16 Figure 14. SF6 in sub-slab soil gas resulting from constant 5 mL/min indoor release rate ...........17 iii List of Acronyms

  12. Groundwater Waters

    Directory of Open Access Journals (Sweden)

    Ramón Llamas

    1999-10-01

    Full Text Available The groundwaters released through springs constituted a basic element for the survival and progressive development of human beings. Man came to learn how to take better advantage of these waters by digging wells, irrigation channels, and galleries. Nevertheless, these activities do not require cooperation nor the collective agreement of relatively large groups of people, as in the case of creating the necessary structures to take advantage of the resources of surfacewaters. The construction and operation of these structures was a powerful factor in the birth of an urban or civil society – the designated water civilizations. The difference between people taking advantage of groundwater, quasi-individually, and those of surface water, where people work in a group, has continued to the present day. Whereas earlier, this difference did not bring about any special problems, the technological advances of this century, especially theturbine pump, have led to a spectacular increase in the use of roundwater. This advance has significantly contributed to reducing hunger in the world and has provided potable water in developing countries. However, the almost generalized lack of planning and control in the exploitation of these groundwaters reflects that they are little or badly understood by the managers of water policy in almost every country. As such, problems have occurred which have often become exaggerated, giving rise to water-myths. These problems, though, should be addressed if the aim is the sustainable usage of surface water as well as groundwater. To counter any misconceptions and to seek solutions to the problems, distinct plans of action can be highlighted: educating the public; fomenting a system of participative management and decisive support for the communities of users of subterranean waters; integrating a sufficient number of experts in hydrology in the various water management organizations;and assuring transparency of the data on

  13. The effects of ground-water development on the water supply in the Post Headquarters area, White Sands Missile Range, New Mexico

    Science.gov (United States)

    Kelly, T.E.; Hearne, Glenn A.

    1976-01-01

    Water-level declines in the Post Headquarters area, White Sands Missile Range, N. Mex., have been accompanied by slight but progressive increases in the concentration of dissolved solids in water withdrawn from the aquifer. Projected water-level declines through 1996 are estimated from a digital simulation model to not exceed 200 feet (61 metres). A conceptual model of water quality provides three potential sources for water that is relatively high in dissolved solids: brine from the Tularosa Basin to the east, slightly saline water beneath the subjacent aquatard, and very slightly saline water from the less permeable units within the aquifer itself. Management of the well field to minimize drawdown and spread the cone of depression would minimize the rate of water-quality deterioration. A well designed monitoring network may provide advance warning of severe or rapid water-quality deterioration.. The Soledad Canyon area 10 miles (16.1 kilometres) south of the Post Headquarters offers the greatest potential for development of additional water supplies.

  14. Modeling the Emission, Transport, and Dispersion of Post-wildfire Dust from Western Sagebrush Landscapes within a Regional Air Quality Framework

    Science.gov (United States)

    Chung, S. H.; Wagenbrenner, N. S.; Lamb, B. K.

    2014-12-01

    Millions of hectares are burned by wildfires each year in the western US. The resulting burn scars are extremely wind erodible surfaces with high loadings of easily entrained ash and soil. Previous work has demonstrated that wind erosion from these burn scars can release large amounts of dust and ash as particulate matter (PM) into the atmosphere, resulting in large impacts on downwind air quality and visibility. Sagebrush-dominated landscapes, where often essentially all vegetation is consumed by the fire, appear to be particularly vulnerable. Climate change predictions indicate more wildfire activity in the western US and, hence, more potential for wind erosion from burn scars. However, these PM sources are not yet accounted for in regional air quality models. Here we describe a modification to the AIRPACT regional air quality modeling framework for simulating the emission, transport and dispersion of PM from post-wildfire burn scars. We present results from a 2012 sagebrush fire in southeast Oregon as a case study. Modeled PM emission rates and downwind concentrations are compared against observations for two major dust events, one which resulted in exceedances of the PM10 National Ambient Air Quality Standard in Boise, Idaho the month after the fire and another which resulted in a significant dust on snow event and subsequent snowmelt in the Owyhee Mountains of southwest Idaho the following spring. Additionally, we present model estimates of annual emissions from all wildfires that occurred in sagebrush landscapes of the western US during the 2012 fire year as an estimate of annual post-fire PM loading potential.

  15. Groundwater and security

    NARCIS (Netherlands)

    Conti, K.I.; Kukurić, N.; Gupta, J.; Pahl-Wostl, C.; Bhaduri, A.; Gupta, J.

    2016-01-01

    Humans abstract two hundred times more groundwater than oil, annually. Ironically, the role of groundwater in water management and supply is underappreciated, partially due to its invisibility. By conducting a literature survey and investigating groundwater information databases, this chapter answer

  16. Radiological characterisation and radon equilibrium factor in the outdoor air of a post-industrial urban area.

    Science.gov (United States)

    Rozas, S; Idoeta, R; Alegría, N; Herranz, M

    2016-01-01

    The radiological characterisation of outdoor air is always a complicated task due to the several radioactive emissions coming from the different radionuclides and also because of the very short half-lives of radionuclides in the natural radioactive series. In some places, this characterisation could result in unusual values because the natural presence of radionuclides with terrestrial origin can be modified by manmade activities. Nonetheless, this characterisation is useful not only for air quality control purposes but also because radon and its progeny in the outdoor air are the main contributors to human exposure from natural sources. In this study, we have carried out air particle sampling, followed by gamma-ray spectrometry, alpha spectrometry and beta counting determinations for this purpose. Subsequently, the outdoor air has been radiologically characterised through the obtained data and using a pre-existing analytical method to take into account the radioactive decays of short half-life radionuclides during sampling, sample preparation and measuring times. Bilbao was chosen to carry out this work. It is a medium-sized town located in northern Spain, close to the Atlantic Ocean and at sea level. This city has a recent industrial past as there were numerous steel mills and other heavy industries, including some quarries, and some open pit mines close to it, which concluded in a remediation program. So, it is a place where the air is potentially modified by manmade activities. The obtained results show that activity concentration values for long-lived radionuclides that precede radon and thoron are in the order of 10(-6) Bq m(-3) and long-lived ones after radon are around 10(-4) Bq m(-3). Thoron progeny are around 2 × 10(-2) Bq m(-3) and radon progeny are around 1.8 Bq m(-3). The mean radon equilibrium factor was 0.18. All of these values are close to the minimum UNSCEAR values, but show some variability, which highlights the importance of

  17. Application of post-discharge region of atmospheric pressure argon and air plasma jet in the contamination control of Candida albicans biofilms

    Directory of Open Access Journals (Sweden)

    Anelise Cristina Osório Cesar Doria

    Full Text Available Introduction:Candida species are responsible for about 80% of hospital fungal infections. Non-thermal plasmas operated at atmospheric pressure are increasingly used as an alternative to existing antimicrobial strategy. This work investigates the action of post-discharge region of a non-thermal atmospheric plasma jet, generated by a gliding arc reactor, on biofilms of standard strain of Candida albicans grown on polyurethane substrate. Methods Samples were divided into three groups: (i non-treated; (ii treated with argon plasma, and (iii treated with argon plus air plasma. Subsequently to plasma treatment, counting of colony-forming units (CFU/ml and cell viability tests were performed. In addition, the surface morphology of the samples was evaluated by scanning electron microscopy (SEM and optical profilometry (OP. Results Reduction in CFU/ml of 85% and 88.1% were observed in groups ii and iii, respectively. Cell viability after treatment also showed reduction of 33% in group ii and 8% in group iii, in comparison with group i (100%. The SEM images allow observation of the effect of plasma chemistry on biofilm structure, and OP images showed a reduction of its surface roughness, which suggests a possible loss of biofilm mass. Conclusion The treatment in post-discharge region and the chemistries of plasma jet tested in this work were effective in controlling Candida albicans biofilm contamination. Finally, it was evidenced that argon plus air plasma was the most efficient to reduce cell viability.

  18. Geochemical Investigations of Groundwater Stability

    Energy Technology Data Exchange (ETDEWEB)

    Bath, Adrian [Intellisci Ltd., Loughborough (United Kingdom)

    2006-05-15

    local palaeohydrogeological conditions. It is likely that inland areas have had longer durations of post-glacial fresh water infiltration than coastal areas, possibly causing greater degrees of dilution and dispersion of preexisting groundwaters and thus overprinting their hydrochemical and isotopic 'fingerprints'. Lower post-glacial hydraulic gradients relative to inland sites may account for the occurrence of more relict cold-climate water at coastal sites. Some general observations are based on rather thin evidence and therefore speculative. Firstly, it seems that glacial melt water penetrated many hundreds of metres and in some places to at least 1,000 m depth. However the low remaining proportions of melt water and of much older saline Shield water suggest that melt water flux did not fully displace pre-existing groundwaters at these depths. Secondly, where there has been post-glacial infiltration of palaeo-Baltic sea water, the density stratification or compartmentalisation effect coupled with low hydraulic gradient has reduced rates of subsequent fresh water circulation after shoreline recession. There are many uncertainties in interpreting these geochemical indicators in terms of the penetration depths of glacial melt waters and the degree to which they replace preexisting groundwaters, of other aspects of groundwater stability, and of comparisons between inland and coastal groundwater systems. Uncertainties derive partly from the reliability of groundwater samples as being representative of in situ conditions, and partly from the non-uniqueness of interpretative models. Future investigations using these approaches need to improve sampling, to make conjunctive use of geochemical and isotopic indicators which have varying timescales and sensitivities, and to integrate these indicators with palaeohydrogeological modelling to support the development of reliable groundwater flow and solute transport models for Performance Assessment.

  19. An ex post cost-benefit analysis of the nitrogen dioxide air pollution control program in Tokyo

    Energy Technology Data Exchange (ETDEWEB)

    Voorhees, A.S.; Araki, S.; Sakai, R.; Sato, H. [University of Tokyo, Tokyo (Japan). Dept. of Public Health and Occupational Medicine

    2000-03-01

    The benefits and costs of past nitrogen dioxide (NO{sub 2}) control policies were calculated for Tokyo, Japan, using environmental, economic, political, demographic, and medical data from 1973 to 1994. The benefits of NO{sub 2} control were estimated as medical expenses and lost work time due to hypothetical no-control air concentrations of NO{sub 2}. Direct costs were calculated as annualized capital expenditures and 1 year's operating costs for regulated industries plus governmental agency expense. 46 refs., 8 figs., 6 tabs.

  20. Groundwater quality and water quality index at Bhandara District.

    Science.gov (United States)

    Rajankar, Prashant N; Tambekar, Dilip H; Wate, Satish R

    2011-08-01

    The present investigation reports the results of a monitoring study focusing on groundwater quality of Bhandara District of central India. Since, remediation of groundwater is very difficult, knowledge of the existing nature, magnitude, and sources of the various pollution loads is a prerequisite to assessing groundwater quality. The water quality index (WQI) value as a function of various physicochemical and bacteriological parameters was determined for groundwater obtained from a total of 21 locations. The WQI during pre-monsoon season varied from 68 to 83, while for post-monsoon, it was between 56 and 76. Significantly (P < 0.01) lower WQI for the post-monsoon season was observed, indicating deterioration of the groundwater overall in corresponding season. The study revealed that groundwater from only 19% locations was fit for domestic use, thus indicating the need of proper treatment before use.

  1. Air-water flow in subsurface systems

    Science.gov (United States)

    Hansen, A.; Mishra, P.

    2013-12-01

    Groundwater traces its roots to tackle challenges of safe and reliable drinking water and food production. When the groundwater level rises, air pressure in the unsaturated Vadose zone increases, forcing air to escape from the ground surface. Abnormally high and low subsurface air pressure can be generated when the groundwater system, rainfall, and sea level fluctuation are favorably combined [Jiao and Li, 2004]. Through this process, contamination in the form of volatile gases may diffuse from the ground surface into residential areas, or possibly move into groundwater from industrial waste sites. It is therefore crucial to understand the combined effects of air-water flow in groundwater system. Here we investigate theoretically and experimentally the effects of air and water flow in groundwater system.

  2. Outdoor air pollution as a possible modifiable risk factor to reduce mortality in post-stroke population.

    Science.gov (United States)

    Desikan, Anita

    2017-03-01

    Outdoor air pollution is a known risk factor for mortality and morbidity. The type of air pollutant most reliably associated with disease is particulate matter (PM), especially finer particulate matter that can reach deeper into the lungs like PM2.5 (particulate matter diameter pollution. This review focuses on one subgroup, long-term stroke survivors, and the emerging evidence suggesting that survivors of a stroke may be at a higher risk from the deleterious effects of PM pollution. While the mechanisms for mortality are still under debate, long-term stroke survivors may be vulnerable to similar mechanisms that underlie the well-established association between PM pollution and cardiovascular disease. The fact that long-term stroke survivors of ischemic, but not hemorrhagic, strokes appear to be more vulnerable to the risk of death from higher PM pollution may also bolster the connection to ischemic heart disease. Survivors of an ischemic stroke may be more vulnerable to dying from higher concentrations of PM pollution than the general population. The clinical implications of this association suggest that reduced exposure to PM pollution may result in fewer deaths amongst stroke survivors.

  3. Coupling of Groundwater Transport and Plant Uptake Models

    DEFF Research Database (Denmark)

    Rein, Arno; Bauer-Gottwein, Peter; Trapp, Stefan

    2010-01-01

    Plants significantly influence contaminant transport and fate. Important processes are uptake of soil and groundwater contaminants, as well as biodegradation in plants and their root zones. Models for the prediction of chemical uptake into plants are required for the setup of mass balances...... to groundwater transport simulation tools. Exemplary simulations of plant uptake were carried out, in order to estimate concentrations in the soilplant- air system and the influence of plants on contaminant mass fluxes from soil to groundwater....

  4. 1998 Comprehensive TNX Area Annual Groundwater and Effectiveness Monitoring Report

    Energy Technology Data Exchange (ETDEWEB)

    Chase, J.

    1999-06-02

    Shallow groundwater beneath the TNX Area at the Savannah River Site has been contaminated with chlorinated volatile organic compounds such as trichloroethylene and carbon tetrachloride. The Interim Action T-1 Air Stripper System began operation on September 16, 1996. A comprehensive groundwater monitoring program was initiated to measure the effectiveness of the system. The Interim Action is meeting its objectives and is capable of continuing to do so until the final groundwater remedial action is in place.

  5. Bioremediation of contaminated groundwater

    Science.gov (United States)

    Hazen, Terry C.; Fliermans, Carl B.

    1995-01-01

    An apparatus and method for in situ remediation of contaminated subsurface soil or groundwater contaminated by chlorinated hydrocarbons. A nutrient fluid is selected to stimulate the growth and reproduction of indigenous subsurface microorganisms that are capable of degrading the contaminants; an oxygenated fluid is selected to create a generally aerobic environment for these microorganisms to degrade the contaminants, leaving only pockets that are anaerobic. The nutrient fluid is injected periodically while the oxygenated fluid is injected continuously and both are extracted so that both are drawn across the plume. The nutrient fluid stimulates microbial colony growth; withholding it periodicially forces the larger, healthy colony of microbes to degrade the contaminants. Treatment is continued until the subsurface concentration of contaminants is reduced to an acceptable, preselected level. The nutrient fluid can be methane and the oxygenated fluid air for stimulating production of methanotrophs to break down chlorohydrocarbons, especially trichloroethylene (TCE) and tetrachloroethylene.

  6. Modelling of flashover performance of an ice-covered resistive glazed post station insulator in presence of an air gap

    Energy Technology Data Exchange (ETDEWEB)

    Jaiswal, Vinay [NSERC/Hydro-Quebec/UQAC Industrial Chair on Atmospheric Icing of Power Network Equipment (CIGELE) and Canada Research Chair on Engineering of Power Network Atmospheric Icing (INGIVRE), Universite du Quebec a Chicoutimi, Quebec, G7H 2B1 (Canada); Farzaneh, Masoud [NSERC/Hydro-Quebec/UQAC Industrial Chair on Atmospheric Icing of Power Network Equipment (CIGELE) and Canada Research Chair on Engineering of Power Network Atmospheric Icing (INGIVRE), Universite du Quebec a Chicoutimi, Quebec, G7H 2B1 (Canada)

    2006-01-07

    The main objective of this paper is to study the electric field distributions around a standard post insulator for the power frequency, lightning impulse (1.2/50 {mu}s) and switching impulse (250/2500 {mu}s) voltages under icing conditions, and these were computed numerically using the finite element method. Thin glaze coating on the insulator requires a very large number of elements for finite element analysis because of the open boundary around the ice-covered insulator. To reduce the number of elements and hence computation time, the region between the domain of interest and infinity was modelled by a form of Kelvin transformation. The simulation results, confirmed by laboratory experiments, show that while a lightning impulse is the limiting factor in the design of a resistive glazed insulator under clean conditions, a switching impulse is the limiting factor under icing conditions.

  7. The air quality and health co-benefits of alternative post-2020 pathways for achieving peak carbon targets in Jiangsu, China

    Science.gov (United States)

    Liu, M.; Bi, J.; Huang, Y.; Kinney, P. L.

    2016-12-01

    Jiangsu, which has three national low-carbon pilot cities, is set to be a model province in China for achieving peak carbon targets before 2030. However, according to local planning of responding to climate change, carbon emissions are projected to keep going up before 2020 even the strictest measures are implemented. In other words, innovative measures must be in action after 2020. This work aimed at assessing the air quality and health co-benefits of alternative post-2020 measures to help remove barriers of policy implementation through tying it to local incentives for air quality improvement. To achieve the aim, we select 2010 as baseline year and develop Bussiness As Usual (BAU) and Traditional Carbon Reduction (TCR) scenarios before 2020. Under BAU, only existing climate and air pollution control policies are considered; under TCR, potential climate policies in local planning and existing air pollution control policies are considered. After 2020, integrated gasification combined cycle (IGCC) plant with carbon capture and storage (CCS) technology and large-scale substitution of renewable energy seem to be two promising pathways for achieving peak carbon targets. Therefore, two additional scenarios (TCR-IGCC and TCR-SRE) are set after 2020. Based on the projections of future energy balances and industrial productions, we estimate the pollutant emissions and simulate PM2.5 and ozone concentrations by 2017, 2020, 2030 and 2050 using CMAQ. Then using health impact assessment approach, the premature deaths are estimated and monetized. Results show that the carbon peak in Jiangsu will be achieved before 2030 only under TCR-IGCC and TCR-SRE scenarios. Under three policy scenarios, Jiangsu's carbon emission control targets would have substantial effects on primary air pollutant emissions far beyond those we estimate would be needed to meet the PM2.5 concentration targets in 2017. Compared with IGCC with CCS, large-scale substitutions of renewable energy bring

  8. The glow discharge inception and post-discharge relaxation of charged and neutral active particles in synthetic air at low pressure

    Science.gov (United States)

    Jovanović, A. P.; Marković, V. Lj; Stamenković, S. N.; Stankov, M. N.

    2015-11-01

    The study of dc glow discharge inception and post-discharge relaxation of charged and neutral active particles in synthetic air at low pressure is presented. The breakdown time delay dependence as a function of relaxation time \\overline{{{t}\\text{d}}}(τ ) (the memory curve) is measured and modelled from milliseconds to the saturation region determined by the cosmic rays and natural radioactivity level. Due to fast conversion \\text{N}2++{{\\text{O}}2}\\to {{\\text{N}}2}+\\text{O}2+ , relaxation of dc discharge in synthetic air in the time interval from one to about ninety milliseconds is dominated by the diffusion decay of molecular oxygen {{O}}_2^ + ions. The change of regimes, from ambipolar to the free diffusion limit, is investigated and the variation of effective diffusion coefficients is determined. The late relaxation is explained by the kinetics of nitrogen atoms, recombining on the surfaces of gas discharge tube and stainless steel electrodes and relevant surface recombination coefficients are determined.

  9. Development of conceptual groundwater flow model for Pali Area ...

    African Journals Online (AJOL)

    use

    be accelerated due to climate change (Mall et al., 2006). Groundwater ... experiencing groundwater pollution problem due to rapid industrialization ... LITERATURE REVIEW ... the impact of a proposed action on existing conditions of ..... Water Air. Soil Pollut., 128: 369-389. Gurunadha Rao VVS, Thangarajan M (1999).

  10. All the Missiles Work Technological Dislocations and Military Innovation: A Case Study in US Air Force Air-to-Air Armament, Post-World War II through Operation Rolling Thunder

    Science.gov (United States)

    2010-06-01

    connected with military might.‖ 8 Looking towards the future in a decidedly ethnocentric manner that York would be proud of, a US Army War College... consuming and complex procedure involving multiple switch actuations and dial manipulations to configure the aircraft radar, acquire the target with...Fighter Weapons Center, January 1973), M-U 42339-15a, MSFRIC, 10. 107 One area that consumed much of the wing‘s focus was the F-4‘s air-to-air

  11. An ex post cost-benefit analysis of the nitrogen dioxide air pollution control program in Tokyo.

    Science.gov (United States)

    Voorhees, A S; Araki, S; Sakai, R; Sato, H

    2000-03-01

    The benefits and costs of past nitrogen dioxide (NO2) control policies were calculated for Tokyo, Japan, using environmental, economic, political, demographic, and medical data from 1973 to 1994. The benefits of NO2 control were estimated as medical expenses and lost work time due to hypothetical no-control air concentrations of NO2. Direct costs were calculated as annualized capital expenditures and 1 year's operating costs for regulated industries plus governmental agency expenses. The major findings were as follows: (1) Using Tokyo's average medical cost of pollution-related illness, the best net estimate of the avoided medical costs due to incidence of phlegm and sputum in adults was 730 billion yen ($6.08 billion; 1 U.S. dollar = 120 yen). (2) The best net estimate of the avoided medical costs due to incidence of lower respiratory illness in children was 93 billion yen ($775 million). (3) Using Tokyo's average duration of pollution-related illness and average wages, the best net estimate of the avoided costs of lost wages in workers was 760 billion yen ($6.33 billion). (4) The best net estimate of the avoided costs of lost wages in mothers caring for their sick children was 100 billion yen ($833 million). (5) Using Tokyo-specific data, the best net costs were estimated as 280 billion yen ($2.33 billion). (6) Using human health and productivity benefits, and annualized capital cost and operating cost estimates, the best net benefits-to-costs ratio was 6:1 (upper limit 44:1; lower limit 0.3:1). Benefit calculations were sensitive to assumptions of mobile source emissions and certain health impacts that were not included. Cost calculations were highly dependent on assumptions of flue gas volume and fuel use. For comparative purposes, we identified other studies for air pollution-related illness. Assumptions that formed the basis for most of the inputs in the present study, such as duration of illness, medical treatment costs, per person illness in children, and

  12. AUTOMATING GROUNDWATER SAMPLING AT HANFORD

    Energy Technology Data Exchange (ETDEWEB)

    CONNELL CW; HILDEBRAND RD; CONLEY SF; CUNNINGHAM DE

    2009-01-16

    Until this past October, Fluor Hanford managed Hanford's integrated groundwater program for the U.S. Department of Energy (DOE). With the new contract awards at the Site, however, the CH2M HILL Plateau Remediation Company (CHPRC) has assumed responsibility for the groundwater-monitoring programs at the 586-square-mile reservation in southeastern Washington State. These programs are regulated by the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response Compensation and Liability Act (CERCLA). The purpose of monitoring is to track existing groundwater contamination from past practices, as well as other potential contamination that might originate from RCRA treatment, storage, and disposal (TSD) facilities. An integral part of the groundwater-monitoring program involves taking samples of the groundwater and measuring the water levels in wells scattered across the site. More than 1,200 wells are sampled each year. Historically, field personnel or 'samplers' have been issued pre-printed forms that have information about the well(s) for a particular sampling evolution. This information is taken from the Hanford Well Information System (HWIS) and the Hanford Environmental Information System (HEIS)--official electronic databases. The samplers used these hardcopy forms to document the groundwater samples and well water-levels. After recording the entries in the field, the samplers turned the forms in at the end of the day and the collected information was posted onto a spreadsheet that was then printed and included in a log book. The log book was then used to make manual entries of the new information into the software application(s) for the HEIS and HWIS databases. This is a pilot project for automating this tedious process by providing an electronic tool for automating water-level measurements and groundwater field-sampling activities. The automation will eliminate the manual forms and associated data entry, improve the

  13. Brackish groundwater in the United States

    Science.gov (United States)

    Stanton, Jennifer S.; Anning, David W.; Brown, Craig J.; Moore, Richard B.; McGuire, Virginia L.; Qi, Sharon L.; Harris, Alta C.; Dennehy, Kevin F.; McMahon, Peter B.; Degnan, James R.; Böhlke, John Karl

    2017-04-05

    in the United States. Previously published digital data relating to brackish groundwater resources were limited to a small number of State- and regional-level studies. Data sources for this assessment ranged from single publications to large datasets and from local studies to national assessments. Geochemical data included concentrations of dissolved solids, major ions, trace elements, nutrients, and radionuclides as well as physical properties of the water (pH, temperature, and specific conductance). Additionally, the database provides selected well information (location, yield, depth, and contributing aquifer) necessary for evaluating the water resource.The assessment was divided into national-, regional-, and aquifer-scale analyses. National-scale analyses included evaluation of the three-dimensional distribution of observed dissolved-solids concentrations in groundwater, the three-dimensional probability of brackish groundwater occurrence, and the geochemical characteristics of saline (greater than or equal to 1,000 mg/L of dissolved solids) groundwater resources. Regional-scale analyses included a summary of the percentage of observed grid cell volume in the region that was occupied by brackish groundwater within the mixture of air, water, and rock for multiple depth intervals. Aquifer-scale analyses focused primarily on four regions that contained the largest amounts of observed brackish groundwater and included a generalized description of hydrogeologic characteristics from previously published work; the distribution of dissolved-solids concentrations; considerations for developing brackish groundwater resources, including a summary of other chemical characteristics that may limit the use of brackish groundwater and the ability of sampled wells producing brackish groundwater to yield useful amounts of water; and the amount of saline groundwater being used in 2010.

  14. EFFECT OF GROUND-WATER REMEDIATION ACTIVITIES ON INDIGENOUS MICROFLORA

    Science.gov (United States)

    The United States Environmental Protection Agency (EPA), working with the Interagency DNAPL Consortium, completed an independent evaluation of microbial responses to ground-water remediation technology demonstrations at Launch Pad 34 at Cape Canaveral Air Station in Brevard Count...

  15. Groundwater recharge: Accurately representing evapotranspiration

    CSIR Research Space (South Africa)

    Bugan, Richard DH

    2011-09-01

    Full Text Available Groundwater recharge is the basis for accurate estimation of groundwater resources, for determining the modes of water allocation and groundwater resource susceptibility to climate change. Accurate estimations of groundwater recharge with models...

  16. Volatile Organic Compounds Identified in Post-Flight Air Analysis of the Multipurpose Logistics Module from International Space Station

    Science.gov (United States)

    Peterson, B.; Wheeler, R.

    Bioregenerative systems involve storing and processing waste along with atmospheric management. The MPLM, Multipurpose Logistics Module, is a reusable logistics carrier and primary delivery system used to resupply the International Space Station (ISS) and return Station cargo that requires a pressurized environment. The cylindrical module is approximately 6.4 meters long, 4.6 meters in diameter, and weighs almost 4,082kg. The module provides storage and additional workspace for up to two astronauts when docked to the ISS. It can carry up to 9,072 kg of supplies, science experiments, spare parts and other logistical components for ISS. There is concern for a potentially hazardous condition caused by contamination of the atmosphere in the MPLM upon return from orbit. This would be largely due to unforeseen spills or container leakage. This has led to the need for special care in handling the returned module prior to processing the module for its next flight. Prior to opening the MPLM, atmospheric samples are analyzed for trace volatile organic compounds, VOC's. It is noted that our analyses also reflect the atmosphere in the ISS on that day of closure. With the re turn of STS-108, 12th ISS Flight (UF1), the analysis showed 24 PPM of methane. This corresponds to the high levels on space station during a time period when the air filtration system was shut off. Chemical characterization of atmospheres on the ISS and MPLM provide useful information for concerns with plant growth experiments on ISS. Work with closed plant growth chambers show potential for VOC's to accumulate to toxic levels for plants. The ethylene levels for 4 MPLM analyses over the course on one year were measured at, 0.070, 0.017, 0.012 and 0.007 PPM. Phytochemical such as ethylene are detected with natural plant physiological events such as flowering and as a result of plant damage or from decaying food. A build up of VOC's may contribute to phytotoxic effects for the plant growth experiments or

  17. Groundwater in the hydrological functioning of wetlands in the Southeast of Buenos Aires Province, Argentina; El agua subterranea en el funcionamiento hidrologico de los humedales del Sudeste Bonaerense, Provincia de Buenos Aires, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Romanelli, A.; Quiroz, O.M.; Massone, H.E.; Martinez, D.E.; Bocanegra, E.

    2010-07-01

    The understanding of the hydrological functioning and the interaction among the different water bodies in an area is essential when a sustainable use of the hydric resources is considered. The hydrogeochemical interpretation of representative water-sample analyses is a useful tool developed for the analysis of hydrological systems. Isotopic techniques are also important tools for the validation and adjustment of conceptual hydrogeological models. The aim of the present paper is to develop depth of knowledge of the conceptual hydrogeological models for wetlands of the Pampa Plain by using hydrochemical and stable isotopic techniques. Three wetlands of different origin were sampled for hydrochemical and stable isotopic analysis (18O and 2H) at different depths. Groundwater and streams were also sampled. Hydrochemical analysis classified La Brava and Los Padres basins as sodium bicarbonate waters, and La Salada Basin as sodium chloride bicarbonate waters. Differences in the isotopic fingerprints and the electrical conductivity values were evident among wetlands: 6.766,8, 762,2 y 647,8 iS/cm in La Salada, Los Padres and La Brava respectively. Hydrochemical and isotopic data allowed us to define the effluent-influent behavior of these wetlands, their main recharge sources and their importance as aquifer recharge areas. (Author).

  18. Air stripping in sieve plate tower for the simulated treatment of the groundwater polluted by perchloroethylene%采用筛板塔吹脱模拟处理四氯乙烯污染地下水

    Institute of Scientific and Technical Information of China (English)

    张卫; 李丽; 林匡飞; 李炳智; 吕树光; 杜晓明; 郭美锦; 崔心红

    2012-01-01

    Perchloroethylene (PCE) as a typical chlorinated hydrocarbon solvent was widely used in industry. Now the groundwater of contaminated sites is badly polluted due to improper handling of PCE, which results in a serious threat to human health and ecological security. Air stripping in sieve plate tower for the treatment of the water polluted by PCE was studied. The results are as follows: After air stripping, PCE concentration declined from 25.68mg/L to 0.62mg/L, and removal rate amounted to 97.59%; Gas-liquid ratio obviously affected PCE removal rate and the optimum gas-liquid ratio was around 200; Initial concentration influenced the removal effect slightly; Waste water was better treated by 4 plates column; Experimental data followed one-order decay model very well; Economic cost was about ¥0.31 per ton of waste water, and therefore air stripping as a pre-treatment process of biochemical method was desirable.%利用自主设计的筛板塔装置模拟吹脱四氯乙烯(PCE)污染废水,综合考察了影响吹脱的各因素(气液体积比、初始浓度和筛板数等),同时对吹脱工艺条件进行了优化,并建立了吹脱模型.研究表明:25.68mg/L PCE废水经吹脱后出水浓度降至0.62mg/L,去除率可达97.59%;气液比对废水的吹脱效果影响很大,且最佳气液比在200左右;PCE初始浓度对去除率的影响并不明显;采用4层塔板时PCE去除效果较好;实验数据很好地遵从一级衰变模型;吨水吹脱成本约为0.31元,可作为后续生化处理的预处理工艺.

  19. Groundwater Managment Districts

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset outlines the location of the five Groundwater Management Districts in Kansas. GMDs are locally formed and elected boards for regional groundwater...

  20. 1997 Comprehensive TNX Area Annual Groundwater and Effectiveness Monitoring Report

    Energy Technology Data Exchange (ETDEWEB)

    Chase, J.

    1998-04-01

    Shallow groundwater beneath the TNX Area at the Savannah River Site (SRS) has been contaminated with chlorinated volatile organic compounds (CVOCs) such as trichloroethylene (TCE) and carbon tetrachloride. In November 1994, an Interim Record of Decision (IROD) was agreed to and signed by the U. S. Department of Energy (DOE), the Environmental Protection Agency (EPA), and the South Carolina Department of Health {ampersand} Environmental Control (SCDHEC). The Interim Record of Decision requires the installation of a hybrid groundwater corrective action (HGCA) to stabilize the plume of groundwater contamination and remove CVOCs dissolved in the groundwater. The hybrid groundwater corrective action included a recovery well network, purge water management facility, air stripper, and an airlift recirculation well. The recirculation well was dropped pursuant to a test that indicated it to be ineffective at the TNX Area. Consequently, the groundwater corrective action was changed from a hybrid to a single action, pump-and-treat approach. The Interim Action (IA) T-1 air stripper system began operation on September 16, 1996. a comprehensive groundwater monitoring program was initiated to measure the effectiveness of the system. As of December 31, 1997, the system has treated 32 million gallons of contaminated groundwater removed 32 pounds of TCE. The recovery well network created a `capture zone` that stabilized the plume of contaminated groundwater.

  1. Air Pollution over North-West Bay of Bengal in the Early Post-Monsoon Season Based on NASA MERRAero Data

    Science.gov (United States)

    Kishcha, Pavel; DaSilva, Arlindo M.; Starobinets, Boris; Alpert, Pinhas

    2013-01-01

    The MERRA Aerosol Reanalysis (MERRAero) has been recently developed at NASA's Global Modeling Assimilation Office (GMAO). This reanalysis is based on a version of the GEOS-5 model radiatively coupled with GOCART aerosols, and it includes assimilation of bias-corrected Aerosol Optical Thickness (AOT) from the MODIS sensor on both Terra and Aqua satellites. Our main finding is that, in October, in the absence of aerosol sources in north-west Bay of Bengal (BoB), MERRAero showed increasing AOT trends over north-west BoB exceeding those over the east of the Ganges basin. The Ganges basin is characterized by significant population growth accompanied by developing industry, agriculture, and increasing transportation: this has resulted in declining air quality. MERRAero data for the period 2002-2009 was used to study AOT trends over north-west Bay of Bengal (BoB) in the early post-monsoon season. This season is characterized by aerosol transport from the Ganges basin to north-west BoB by prevailing winds; and still significant rainfall of over 150 mmmonth. Different aerosol components showed strong increasing AOT trends over north-west BoB. The following factors contributed to the increasing AOT trend over the area in question in October: an increasing number of days when prevailing winds blew from land to sea, resulting in a drier environment and an increase in air pollution over north-west BoB; wind convergence was observed over north-west BoB causing the accumulation of aerosol particles over that region, when prevailing winds blew from land to sea. MERRAero aerosol reanalysis can be used on a global scale.

  2. Learning Large Lessons: The Evolving Roles of Ground Power and Air Power in the Post-Cold War Era. Executive Summary

    Science.gov (United States)

    2007-01-01

    33, III-34. 21 Carl R. Pivarsky, Jr., Airpower in the Context of a Dysfunctional Joint Doctrine, Maxwell Air Force Base, Ala.: Air War College...Airpower in the Context of a Dysfunctional Joint Doctrine, Maxwell Air Force Base, Ala.: Air War College, Maxwell Paper No. 7, 1997. Plummer, Anne, “Army

  3. Manganese oxide octahedral molecular sieve K-OMS-2 as catalyst in post plasma-catalysis for trichloroethylene degradation in humid air

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Dinh, M.T. [Université Lille, Sciences et Technologies, Unité de Catalyse et Chimie du Solide UMR CNRS UCCS 8181, 59655 Villeneuve d’Ascq (France); The University of Da-Nang, University of Science and Technology, 54, Nguyen Luong Bang, Da-Nang (Viet Nam); Giraudon, J.-M., E-mail: jean-marc.giraudon@univ-lille1.fr [Université Lille, Sciences et Technologies, Unité de Catalyse et Chimie du Solide UMR CNRS UCCS 8181, 59655 Villeneuve d’Ascq (France); Vandenbroucke, A.M.; Morent, R.; De Geyter, N. [Ghent University, Faculty of Engineering and Architecture, Department of Applied Physics, Research Unit Plasma Technology, Sint-Pietersnieuwstraat 41, 9000 Ghent (Belgium); Lamonier, J.-F. [Université Lille, Sciences et Technologies, Unité de Catalyse et Chimie du Solide UMR CNRS UCCS 8181, 59655 Villeneuve d’Ascq (France)

    2016-08-15

    Highlights: • Post plasma catalysis: negative DC glow discharge combined with a cryptomelane. • The α-MnO{sub 2} catalyst totally decomposes the NTP generated ozone. • Active oxygen oxidizes the end-up plasma VOC by-products. - Abstract: The total oxidation of trichloroethylene (TCE) in air at low relative humidity (RH = 10%) in the presence of CO{sub 2} (520 ppmv) was investigated in function of energy density using an atmospheric pressure negative DC luminescent glow discharge combined with a cryptomelane catalyst positioned downstream of the plasma reactor at a temperature of 150 °C. When using Non-Thermal Plasma (NTP) alone, it is found a low COx (x = 1–2) yield in agreement with the detection of gaseous polychlorinated by-products in the outlet stream as well as ozone which is an harmful pollutant. Introduction of cryptomelane enhanced trichloroethylene removal, totally inhibited plasma ozone formation and increased significantly the COx yield. The improved performances of the hybrid system were mainly ascribed to the total destruction of plasma generated ozone on cryptomelane surface to produce active oxygen species. Consequently these active oxygen species greatly enhanced the abatement of the plasma non-reacted TCE and completely destroyed the hazardous plasma generated polychlorinated intermediates. The facile redox of Mn species associated with oxygen vacancies and mobility as well as the textural properties of the catalyst might also contribute as a whole to the efficiency of the process.

  4. Statistical assessment of groundwater resources in Washim district (India).

    Science.gov (United States)

    Rajankar, P N; Tambekar, D H; Ramteke, D S; Wate, S R

    2011-01-01

    Groundwater quality of Washim district of Maharashtra (India) was assessed using quality parameters and water quality index (WQI). In this study, the WQI was analyzed by using pH, turbidity, temperature, nitrates, total phosphates, dissolved oxygen, biochemical oxygen demand, total solids, total coliforms and faecal coliforms, respectively for residential and commercial uses. All the parameters were analyzed both in pre-monsoon and post-monsoon seasons to assess the groundwater quality and seasonal variations. The parameters like turbidity, solids and coliforms showed the seasonal variations. The WQI varied from 72 to 88 in pre-monsoon season and 64 to 88 in post-monsoon season. The results indicate that all groundwater samples in the study area have good water quality in pre-monsoon season but in post-monsoon season 9 percent samples indicated the change in water quality from good to medium, which reveals seasonal variation and groundwater quality deterioration.

  5. Groundwater hydrogeochemical characteristics in rehabilitated coalmine spoils

    Science.gov (United States)

    Gomo, M.; Masemola, E.

    2016-04-01

    The investigation aims to identify and describe hydrogeochemical processes controlling the evolution of groundwater chemistry in rehabilitated coalmine spoils and their overall influence on groundwater quality at a study area located in the Karoo basin of South Africa. A good understanding of the processes that controls the evolution of the mine water quality is vital for the planning, application and management of post-mining remedial actions. The study utilises scatter plots, statistical analysis, PHREEQC hydrogeochemical modelling, stoichiometric reaction ratios analysis, and the expanded Durov diagram as complimentary tools to interpret the groundwater chemistry data collected from monitoring boreholes from 1995 to 2014. Measured pH ranging between 6-8 and arithmetic mean of 7.32 shows that the groundwater system is characterised by circumneutral hydrogeochemical conditions period. Comparison of measured groundwater ion concentrations to theoretical reaction stoichiometry identifies Dolomite-Acid Mine Drainage (AMD) neutralisation as the main hydrogeochemical process controlling the evolution of the groundwater chemistry. Hydrogeochemical modelling shows that, the groundwater has temporal variations of calcite and dolomite saturation indices characterised by alternating cycles of over-saturation and under-saturation that is driven by the release of sulphate, calcium and magnesium ions from the carbonate-AMD neutralization process. Arithmetic mean concentrations of sulphate, calcium and magnesium are in the order of 762 mg/L, 141 mg/L and 108 mg/L. Calcium and magnesium ions contribute to very hard groundwater quality conditions. Classification based on total dissolved solids (TDS), shows the circumneutral water is of poor to unacceptable quality for drinking purposes. Despite its ability to prevent AMD formation and leaching of metals, the dolomite-AMD neutralisation process can still lead to problems of elevated TDS and hardness which mines should be aware of

  6. Halon-1301, a new Groundwater Age Tracer

    Science.gov (United States)

    Beyer, Monique; van der Raaij, Rob; Morgenstern, Uwe; Jackson, Bethanna

    2015-04-01

    Groundwater dating is an important tool to assess groundwater resources in regards to direction and time scale of groundwater flow and recharge and to assess contamination risks and manage remediation. To infer groundwater age information, a combination of different environmental tracers, such as tritium and SF6, are commonly used. However ambiguous age interpretations are often faced, due to a limited set of available tracers and limitations of each tracer method when applied alone. There is a need for additional, complementary groundwater age tracers. We recently discovered that Halon-1301, a water soluble and entirely anthropogenic gaseous substance, may be a promising candidate [Beyer et al, 2014]. Halon-1301 can be determined along with SF6, SF5CF3 and CFC-12 in groundwater using a gas chromatography setup with attached electron capture detector developed by Busenberg and Plummer [2008]. Halon-1301 has not been assessed in groundwater. This study assesses the behaviour of Halon-1301 in water and its suitability as a groundwater age tracer. We determined Halon-1301 in 17 groundwater and various modern (river) waters sites located in 3 different groundwater systems in the Wellington Region, New Zealand. These waters have been previously dated with tritium, CFC-12, CFC-11 and SF6 with mean residence times ranging from 0.5 to over 100 years. The waters range from oxic to anoxic and some show evidence of CFC contamination or degradation. This allows us to assess the different properties affecting the suitability of Halon-1301 as groundwater age tracer, such as its conservativeness in water and local contamination potential. The samples are analysed for Halon-1301 and SF6simultaneously, which allows identification of issues commonly faced when using gaseous tracers such as contamination with modern air during sampling. Overall we found in the assessed groundwater samples Halon-1301 is a feasible new groundwater tracer. No sample indicated significantly elevated

  7. DYNAMICS OF AGRICULTURAL GROUNDWATER EXTRACTION

    OpenAIRE

    Hellegers, Petra J.G.J.; Zilberman, David; van Ierland, Ekko C.

    2001-01-01

    Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is developed to study socially optimal agricultural shallow groundwater extraction patterns. It shows the importance of stock size to slow down changes in groundwater quality.

  8. DYNAMICS OF AGRICULTURAL GROUNDWATER EXTRACTION

    OpenAIRE

    Hellegers, Petra J.G.J.; Zilberman, David; van Ierland, Ekko C.

    2001-01-01

    Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is developed to study socially optimal agricultural shallow groundwater extraction patterns. It shows the importance of stock size to slow down changes in groundwater quality.

  9. Speciation of selenium in groundwater: Seasonal variations and redox transformations

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A. Ramesh [Chemical Laboratory, Central Groundwater Board, South Eastern Coastal Region, E1, Rajaji Bhavan, Besant Nagar, Chennai 600 090 (India); Riyazuddin, P., E-mail: riyazdr@yahoo.co.uk [Department of Analytical Chemistry, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu (India)

    2011-08-15

    Highlights: {yields} Selenium(VI) was the predominant species of Se present in groundwater. {yields} Groundwater recharge increased Se mobilization. {yields} Dissolved oxygen and redox potential control the mobilization of soil selenium. {yields} Shallow groundwater is susceptible for more selenium enrichment than deeper ones. - Abstract: Speciation of selenium in groundwater is essential from the viewpoint of toxicity to organisms and biogeochemical cycling. Selenium speciation in groundwater is controlled by aquifer redox conditions, microbial transformations, dissolved oxygen (DO) and other redox couples. A suburban area of Chennai city in India, where improper waste disposal measures have been practiced is selected for this study. Se(IV), Se(VI) and other hydrochemical parameters were monitored in shallow ground water during pre- and post-monsoon seasons for a period of three years. The objective of the study was to investigate the effect of groundwater recharge on selenium speciation. The concentration of Se(IV), and Se(VI) ranged between 0.15-0.43 {mu}g L{sup -1} and 0.16-4.73 {mu}g L{sup -1}, respectively. During post-monsoon period the concentration of Se(IV), and Se(VI) ranged between 0.15-1.25 {mu}g L{sup -1} and 0.58-10.37 {mu}g L{sup -1}, respectively. Se(VI) was the dominant species of selenium during the pre- and post-monsoon periods. During the post-monsoon periods, leaching of selenium from soil was more effective due to the increased oxidizing nature of the groundwater as indicated by the DO and redox potential (Eh) measurements. This finding has important implications on the behavior of selenium in groundwater, and also on the health of people consuming groundwater from seleniferous areas.

  10. Groundwater sustainability strategies

    Science.gov (United States)

    Gleeson, Tom; VanderSteen, Jonathan; Sophocleous, Marios A.; Taniguchi, Makoto; Alley, William M.; Allen, Diana M.; Zhou, Yangxiao

    2010-01-01

    Groundwater extraction has facilitated significant social development and economic growth, enhanced food security and alleviated drought in many farming regions. But groundwater development has also depressed water tables, degraded ecosystems and led to the deterioration of groundwater quality, as well as to conflict among water users. The effects are not evenly spread. In some areas of India, for example, groundwater depletion has preferentially affected the poor. Importantly, groundwater in some aquifers is renewed slowly, over decades to millennia, and coupled climate–aquifer models predict that the flux and/or timing of recharge to many aquifers will change under future climate scenarios. Here we argue that communities need to set multigenerational goals if groundwater is to be managed sustainably.

  11. Dynamics of Agricultural Groundwater Extraction

    NARCIS (Netherlands)

    Hellegers, P.J.G.J.; Zilberman, D.; Ierland, van E.C.

    2001-01-01

    Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is

  12. Earthquakes trigger the loss of groundwater biodiversity

    Science.gov (United States)

    Galassi, Diana M. P.; Lombardo, Paola; Fiasca, Barbara; di Cioccio, Alessia; di Lorenzo, Tiziana; Petitta, Marco; di Carlo, Piero

    2014-09-01

    Earthquakes are among the most destructive natural events. The 6 April 2009, 6.3-Mw earthquake in L'Aquila (Italy) markedly altered the karstic Gran Sasso Aquifer (GSA) hydrogeology and geochemistry. The GSA groundwater invertebrate community is mainly comprised of small-bodied, colourless, blind microcrustaceans. We compared abiotic and biotic data from two pre-earthquake and one post-earthquake complete but non-contiguous hydrological years to investigate the effects of the 2009 earthquake on the dominant copepod component of the obligate groundwater fauna. Our results suggest that the massive earthquake-induced aquifer strain biotriggered a flushing of groundwater fauna, with a dramatic decrease in subterranean species abundance. Population turnover rates appeared to have crashed, no longer replenishing the long-standing communities from aquifer fractures, and the aquifer became almost totally deprived of animal life. Groundwater communities are notorious for their low resilience. Therefore, any major disturbance that negatively impacts survival or reproduction may lead to local extinction of species, most of them being the only survivors of phylogenetic lineages extinct at the Earth surface. Given the ecological key role played by the subterranean fauna as decomposers of organic matter and ``ecosystem engineers'', we urge more detailed, long-term studies on the effect of major disturbances to groundwater ecosystems.

  13. Earthquakes trigger the loss of groundwater biodiversity.

    Science.gov (United States)

    Galassi, Diana M P; Lombardo, Paola; Fiasca, Barbara; Di Cioccio, Alessia; Di Lorenzo, Tiziana; Petitta, Marco; Di Carlo, Piero

    2014-09-03

    Earthquakes are among the most destructive natural events. The 6 April 2009, 6.3-Mw earthquake in L'Aquila (Italy) markedly altered the karstic Gran Sasso Aquifer (GSA) hydrogeology and geochemistry. The GSA groundwater invertebrate community is mainly comprised of small-bodied, colourless, blind microcrustaceans. We compared abiotic and biotic data from two pre-earthquake and one post-earthquake complete but non-contiguous hydrological years to investigate the effects of the 2009 earthquake on the dominant copepod component of the obligate groundwater fauna. Our results suggest that the massive earthquake-induced aquifer strain biotriggered a flushing of groundwater fauna, with a dramatic decrease in subterranean species abundance. Population turnover rates appeared to have crashed, no longer replenishing the long-standing communities from aquifer fractures, and the aquifer became almost totally deprived of animal life. Groundwater communities are notorious for their low resilience. Therefore, any major disturbance that negatively impacts survival or reproduction may lead to local extinction of species, most of them being the only survivors of phylogenetic lineages extinct at the Earth surface. Given the ecological key role played by the subterranean fauna as decomposers of organic matter and "ecosystem engineers", we urge more detailed, long-term studies on the effect of major disturbances to groundwater ecosystems.

  14. Earthquakes trigger the loss of groundwater biodiversity

    Science.gov (United States)

    Galassi, Diana M. P.; Lombardo, Paola; Fiasca, Barbara; Di Cioccio, Alessia; Di Lorenzo, Tiziana; Petitta, Marco; Di Carlo, Piero

    2014-01-01

    Earthquakes are among the most destructive natural events. The 6 April 2009, 6.3-Mw earthquake in L'Aquila (Italy) markedly altered the karstic Gran Sasso Aquifer (GSA) hydrogeology and geochemistry. The GSA groundwater invertebrate community is mainly comprised of small-bodied, colourless, blind microcrustaceans. We compared abiotic and biotic data from two pre-earthquake and one post-earthquake complete but non-contiguous hydrological years to investigate the effects of the 2009 earthquake on the dominant copepod component of the obligate groundwater fauna. Our results suggest that the massive earthquake-induced aquifer strain biotriggered a flushing of groundwater fauna, with a dramatic decrease in subterranean species abundance. Population turnover rates appeared to have crashed, no longer replenishing the long-standing communities from aquifer fractures, and the aquifer became almost totally deprived of animal life. Groundwater communities are notorious for their low resilience. Therefore, any major disturbance that negatively impacts survival or reproduction may lead to local extinction of species, most of them being the only survivors of phylogenetic lineages extinct at the Earth surface. Given the ecological key role played by the subterranean fauna as decomposers of organic matter and “ecosystem engineers”, we urge more detailed, long-term studies on the effect of major disturbances to groundwater ecosystems. PMID:25182013

  15. Human health and groundwater

    Science.gov (United States)

    The high quality of most groundwaters, consequent upon the self-purification capacity of subsurface strata, has long been a key factor in human health and wellbeing. More than 50% of the world’s population now rely on groundwater for their supply of drinking water – and in most circumstances a prope...

  16. Groundwater and Distribution Workbook.

    Science.gov (United States)

    Ekman, John E.

    Presented is a student manual designed for the Wisconsin Vocational, Technical and Adult Education Groundwater and Distribution Training Course. This program introduces waterworks operators-in-training to basic skills and knowledge required for the operation of a groundwater distribution waterworks facility. Arranged according to the general order…

  17. Well Construction Details, Groundwater Elevations, and Figures for the Tijeras Arroyo Groundwater Area at Sandia National Laboratories, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Copland, John R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-01-01

    This Sandia National Laboratories / New Mexico (SNL/NM) submittal contains groundwater information that the United States Geological Survey (USGS) has requested. The USGS will use the information to assist Kirtland Air Force Base (KAFB) in its ongoing groundwater studies. The information in this submittal contains well-construction details and groundwater-elevation data for monitoring wells that SNL/NM has installed. Relevant well-construction data from other government agencies are also summarized. This submittal contains four data tables and three figures. Information in the tables has been used by SNL/NM to prepare groundwater compliance reports that have previously incorporated the three figures. The figures depict the potentiometric surface for the Perched Groundwater System, the potentiometric surface for the Regional Aquifer, and a Conceptual Site Model for the vicinity of Tijeras Arroyo in the northern portion of KAFB.

  18. Trends in groundwater quality in relation to groundwater age

    NARCIS (Netherlands)

    Visser, A.

    2009-01-01

    Groundwater is a valuable natural resource and as such should be protected from chemical pollution. Because of the long travel times of pollutants through groundwater bodies, early detection of groundwater quality deterioration is necessary to efficiently protect groundwater bodies. The aim of this

  19. Trends in groundwater quality in relation to groundwater age

    NARCIS (Netherlands)

    Visser, A.

    2009-01-01

    Groundwater is a valuable natural resource and as such should be protected from chemical pollution. Because of the long travel times of pollutants through groundwater bodies, early detection of groundwater quality deterioration is necessary to efficiently protect groundwater bodies. The aim of this

  20. Global depletion of groundwater resources

    NARCIS (Netherlands)

    Wada, Y.; Beek, L.P.H. van; van Kempen, C.M.; Reckman, J.W.T.M.; Vasak, S.; Bierkens, M.F.P.

    2010-01-01

    In regions with frequent water stress and large aquifer systems groundwater is often used as an additional water source. If groundwater abstraction exceeds the natural groundwater recharge for extensive areas and long times, overexploitation or persistent groundwater depletion occurs. Here we provid

  1. Use of Surfactants to Decrease Air-Water Interfacial Tension During Sparging

    Science.gov (United States)

    Air sparging is a remediation procedure of injecting air into polluted ground water. The primary intention of air sparging is to promote biodegradation of volatile organic compounds (VOCs) in the groundwater passing through the treatment sector. Sparging treatment efficiency dep...

  2. Use of Surfactants to Decrease Air-Water Interfacial Tension During Sparging (OKC, OK)

    Science.gov (United States)

    Air sparging is a remediation procedure of injecting air into polluted ground water. The primary intention of air sparging is to promote biodegradation of volatile organic compounds (VOCs) in the groundwater passing through the treatment sector. Sparging treatment efficiency dep...

  3. Groundwater data network interoperability

    Science.gov (United States)

    Brodaric, Boyan; Booth, Nathaniel; Boisvert, Eric; Lucido, Jessica M.

    2016-01-01

    Water data networks are increasingly being integrated to answer complex scientific questions that often span large geographical areas and cross political borders. Data heterogeneity is a major obstacle that impedes interoperability within and between such networks. It is resolved here for groundwater data at five levels of interoperability, within a Spatial Data Infrastructure architecture. The result is a pair of distinct national groundwater data networks for the United States and Canada, and a combined data network in which they are interoperable. This combined data network enables, for the first time, transparent public access to harmonized groundwater data from both sides of the shared international border.

  4. Groundwater contamination in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Tase, Norio [Univ. of Tsukuba, Ibaraki (Japan)

    1992-07-01

    Problems on groundwater contamination in Japan are briefly summarized in this paper. Although normal physical conditions in Japan restrict the possibilities of groundwater contamination, human activities are threatening groundwater resources. A survey by the Environment Agency of Japan showed nationwide spreading of organic substances, such as trichloroethylene as well as nitrogen compounds. Synthetic detergents have also been detected even in rural areas and in deep confined aquifers, although their concentrations are not as high. Public awareness of agrichemical or pesticides abuse, especially from golf courses, is apparent. Other problems such as nitrate-nitrogen, leachate from landfills, and the leaking of underground storage tanks are also discussed. 9 refs., 3 figs., 4 tabs.

  5. Groundwater contamination in Japan

    Science.gov (United States)

    Tase, Norio

    1992-07-01

    Problems on groundwater contamination in Japan are briefly summarized in this paper. Although normal physical conditions in Japan restrict the possibilities of groundwater contamination, human activities are threatening groundwater resources. A survey by the Environment Agency of Japan showed nationwide spreading of organic substances, such as trichloroethylene as well as nitrogen compounds. Synthetic detergents have also been detected even in rural areas and in deep confined aquifers, although their concentrations are not as high. Public awareness of agrichemical or pesticides abuse, especially from golf courses, is apparent. Other problems such as nitrate-nitrogen, leachate from landfills, and the leaking of underground storage tanks are also discussed.

  6. Assessment of Halon-1301 as a groundwater age tracer

    Science.gov (United States)

    Beyer, M.; van der Raaij, R.; Morgenstern, U.; Jackson, B.

    2015-06-01

    Groundwater dating is an important tool to assess groundwater resources in regards to their dynamics, i.e. direction and timescale of groundwater flow and recharge, contamination risks and manage remediation. To infer groundwater age information, a combination of different environmental tracers, such as tritium and SF6, are commonly used. However, ambiguous age interpretations are often faced, due to a limited set of available tracers and their individual restricted application ranges. For more robust groundwater dating multiple tracers need to be applied complementarily (or other characterisation methods need to be used to complement tracer information). It is important that additional, groundwater age tracers are found to ensure robust groundwater dating in future. We have recently suggested that Halon-1301, a water soluble and entirely anthropogenic gaseous substance, may be a promising candidate, but its behaviour in water and suitability as a groundwater age tracer had not yet been assessed in detail. In this study, we determined Halon-1301 and inferred age information in 17 New Zealand groundwater samples and various modern (river) water samples. The samples were simultaneously analysed for Halon-1301 and SF6, which allowed for identification of issues such as contamination of the water with modern air during sampling. All analysed groundwater sites had also been previously dated with tritium, CFC-12, CFC-11 and SF6, and exhibited mean residence times ranging from modern (close to 0 years) to over 100 years. The investigated groundwater samples ranged from oxic to highly anoxic. All samples with available CFC data were degraded and/or contaminated in one or both of CFC-11 and CFC-12. This allowed us to make a first attempt of assessing the conservativeness of Halon-1301 in water, in terms of presence of local sources and its sensitivity towards degradation, which could affect the suitability of Halon-1301 as groundwater age tracer. Overall we found Halon-1301

  7. Assessment of Halon-1301 as a groundwater age tracer

    Directory of Open Access Journals (Sweden)

    M. Beyer

    2015-01-01

    Full Text Available Groundwater dating is an important tool to assess groundwater resources in regards to their dynamics, i.e. direction and time scale of groundwater flow and recharge, to assess contamination risks and manage remediation. To infer groundwater age information, a combination of different environmental tracers, such as tritium and SF6, are commonly used. However, ambiguous age interpretations are often faced, due to a limited set of available tracers and their individual restricted application ranges. For more robust groundwater dating multiple tracers need to be applied complementarily and it is vital that additional, groundwater age tracers are found to ensure robust groundwater dating in future. We recently suggested that Halon-1301, a water soluble and entirely anthropogenic gaseous substance, may be a promising candidate, but its behaviour in water and suitability as a groundwater age tracer had not yet been assessed in detail. In this study, we determine Halon-1301 and infer age information in 17 New Zealand groundwaters and various modern (river water samples. The samples are simultaneously analysed for Halon-1301 and SF6, which allows identification of issues such as contamination of the water with modern air during sampling. Water at all analysed groundwater sites have also been previously dated with tritium, CFC-12, CFC-11 and SF6, and exhibit mean residence times ranging from modern (close to 0 years to over 100 years. The investigated groundwater ranged from oxic to highly anoxic, and some showed evidence of CFC contamination or degradation. This allowed us to make a first attempt of assessing the conservativeness of Halon-1301 in water, in terms of presence of local sources and its sensitivity towards degradation etc., which could affect the suitability of Halon-1301 as groundwater age tracer. Overall we found Halon-1301 reliably inferred the mean residence time of groundwater recharged between 1980 and 2014. Where direct age comparison

  8. Shallow bedrock limits groundwater seepage-based headwater climate refugia

    Science.gov (United States)

    Briggs, Martin; Lane, John; Snyder, Craig D.; White, Eric A.; Johnson, Zachary; Nelms, David L.; Hitt, Nathaniel P.

    2017-01-01

    Groundwater/surface-water exchanges in streams are inexorably linked to adjacent aquifer dynamics. As surface-water temperatures continue to increase with climate warming, refugia created by groundwater connectivity is expected to enable cold water fish species to survive. The shallow alluvial aquifers that source groundwater seepage to headwater streams, however, may also be sensitive to seasonal and long-term air temperature dynamics. Depth to bedrock can directly influence shallow aquifer flow and thermal sensitivity, but is typically ill-defined along the stream corridor in steep mountain catchments. We employ rapid, cost-effective passive seismic measurements to evaluate the variable thickness of the shallow colluvial and alluvial aquifer sediments along a headwater stream supporting cold water-dependent brook trout (Salvelinus fontinalis) in Shenandoah National Park, VA, USA. Using a mean depth to bedrock of 2.6 m, numerical models predicted strong sensitivity of shallow aquifer temperature to the downward propagation of surface heat. The annual temperature dynamics (annual signal amplitude attenuation and phase shift) of potential seepage sourced from the shallow modeled aquifer were compared to several years of paired observed stream and air temperature records. Annual stream water temperature patterns were found to lag local air temperature by ∼8–19 d along the stream corridor, indicating that thermal exchange between the stream and shallow groundwater is spatially variable. Locations with greater annual signal phase lag were also associated with locally increased amplitude attenuation, further suggestion of year-round buffering of channel water temperature by groundwater seepage. Numerical models of shallow groundwater temperature that incorporate regional expected climate warming trends indicate that the summer cooling capacity of this groundwater seepage will be reduced over time, and lower-elevation stream sections may no longer serve as larger

  9. Canada's groundwater resources

    National Research Council Canada - National Science Library

    Rivera, Alfonso

    2014-01-01

    Groundwater is essential for life in arid and semiarid region. It is also important in humid regions, and is one of the fundamental requirements for the maintenance of natural landscapes and aquatic ecosystem...

  10. Groundwater Capture Zones

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Source water protection areas are delineated for each groundwater-based public water supply system using available geologic and hydrogeologic information to...

  11. High-fluoride groundwater.

    Science.gov (United States)

    Rao, N Subba

    2011-05-01

    Fluoride (F(-)) is essential for normal bone growth, but its higher concentration in the drinking water poses great health problems and fluorosis is common in many parts of India. The present paper deals with the aim of establishment of facts of the chemical characteristics responsible for the higher concentration of F(-) in the groundwater, after understanding the chemical behavior of F(-) in relation to pH, total alkalinity (TA), total hardness (TH), carbonate hardness (CH), non-carbonate hardness (NCH), and excess alkalinity (EA) in the groundwater observed from the known areas of endemic fluorosis zones of Andhra Pradesh that have abundant sources of F(-)-bearing minerals of the Precambrians. The chemical data of the groundwater shows that the pH increases with increase F(-); the concentration of TH is more than the concentration of TA at low F(-) groundwater, the resulting water is represented by NCH; the TH has less concentration compared to TA at high F(-) groundwater, causing the water that is characterized by EA; and the water of both low and high concentrations of F(-) has CH. As a result, the F(-) has a positive relation with pH and TA, and a negative relation with TH. The operating mechanism derived from these observations is that the F(-) is released from the source into the groundwater by geochemical reactions and that the groundwater in its flowpath is subjected to evapotranspiration due to the influence of dry climate, which accelerates a precipitation of CaCO(3) and a reduction of TH, and thereby a dissolution of F(-). Furthermore, the EA in the water activates the alkalinity in the areas of alkaline soils, leading to enrichment of F(-). Therefore, the alkaline condition, with high pH and EA, and low TH, is a more conducive environment for the higher concentration of F(-) in the groundwater.

  12. Landscape Predictors of Groundwater Influence on Stream Temperature in Forested Headwater Catchments

    Science.gov (United States)

    Johnson, Z. C.; Hitt, N. P.; Snyder, C.

    2015-12-01

    Understanding groundwater contribution to stream temperature is critical for predicting climate effects on thermal habitat in streams. Recent studies suggest that in forested watersheds, groundwater influences on water temperature can be inferred by air-water temperature regression models. The goal of this research is to identify landscape attributes that predict groundwater influence at the stream reach spatial scale. We examined estimates of groundwater influence at 81 sites within nine watersheds in Shenandoah National Park, Virginia, USA, over two summers (2012-2013) and determined effects of varying groundwater contribution on thermal sensitivity (extent to which stream temperature changes with unit change in air temperature). We used a GIS to derive a series of landscape factors based upon gradients in geomorphic, geological, and network topology parameters to predict the spatial distribution of groundwater influence on thermal sensitivity during baseflow summer months. We found that groundwater thermal influence was patchy, varying as much within as among watersheds, and that spatial variation in groundwater contribution is influenced by complex interactions among landscape attributes. Moreover, although groundwater influence was relatively consistent among summers at most sites, it changed dramatically at others. There are indications that recent (within one year) precipitation patterns are strongly influencing these transient groundwater sites.

  13. Effects of a constructed wetland and pond system upon shallow groundwater quality

    Science.gov (United States)

    Ying Ouyang

    2013-01-01

    Constructed wetland (CW) and constructed pond (CP) are commonly utilized for removal of excess nutrients and certain pollutants from stormwater. This study characterized shallow groundwater quality for pre- and post-CW and CP system conditions using data from monitoring wells. Results showed that the average concentrations of groundwater phosphorus (P) decreased from...

  14. Limits to global groundwater consumption

    Science.gov (United States)

    de Graaf, I.; Van Beek, L. P.; Sutanudjaja, E.; Wada, Y.; Bierkens, M. F.

    2016-12-01

    Groundwater is the largest accessible freshwater resource worldwide and is of critical importance for irrigation, and so for global food security. For many regions of the world where groundwater abstraction exceeds groundwater recharge, persistent groundwater depletion occurs. A direct consequence of depletion is falling groundwater levels, reducing baseflows to rivers, harming ecosystems. Also, pumping costs increase, wells dry up and land subsidence can occur. Water demands are expected to increase further due to growing population, economic development and climate change, posing the urgent question how sustainable current water abstractions are worldwide and where and when these abstractions approach conceivable limits with all the associated problems. Here, we estimated past and future trends (1960-2050) in groundwater levels resulting from changes in abstractions and climate and predicted when limits of groundwater consumption are reached. We explored these limits by predicting where and when groundwater levels drop that low that groundwater becomes unattainable for abstractions and how river flows are affected. Water availabilities, abstractions, and lateral groundwater flows are simulated (5 arcmin. resolution) using a coupled version of the global hydrological model PCR-GLOBWB and a groundwater model based on MODFLOW. The groundwater model includes a parameterization of the worlds confined and unconfined aquifer systems, needed for a realistic simulation of groundwater head dynamics. Results show that, next to the existing regions experiencing groundwater depletion (like India, Pakistan, Central Valley) new regions will develop, e.g. Southern Europe, the Middle East, and Africa. Using a limit that reflects present-day feasibility of groundwater abstraction, we estimate that in 2050 groundwater becomes unattainable for 20% of the global population, mainly in the developing countries and pumping cost will increase significantly. Largest impacts are found

  15. Modeling of groundwater draft based on satellite-derived crop acreage estimation over an arid region of northwest India

    Science.gov (United States)

    Bhadra, Bidyut Kumar; Kumar, Sanjay; Paliwal, Rakesh; Jeyaseelan, A. T.

    2016-11-01

    Over-exploitation of groundwater for agricultural crops puts stress on the sustainability of natural resources in the arid region of Rajasthan state, India. Hydrogeological study of groundwater levels of the study area during the pre-monsoon (May to June), post-monsoon (October to November) and post-irrigation (February to March) seasons of 2004-2005 to 2011-2012 shows a steady decline of groundwater levels at the rate of 1.28-1.68 m/year, mainly due to excessive groundwater draft for irrigation. Due to the low density of the groundwater observation-well network in the study area, assessment of groundwater draft, and thus groundwater resource management, becomes a difficult task. To overcome the situation, a linear groundwater draft model (LGDM) has been developed based on the empirical relationship between satellite-derived crop acreage and the observed groundwater draft for the year 2003-2004. The model has been validated for a decade, during three year-long intervals (2005-2006, 2008-2009 and 2011-2012) using groundwater draft, estimated through a discharge factor method. Further, the estimated draft was validated through observed pumping data from random sampled villages (2011-2012). The results suggest that the developed LGDM model provides a good alternative to the estimation of groundwater draft based on satellite-based crop area in the absence of groundwater observation wells in arid regions of northwest India.

  16. Examining the impacts of increased corn production on groundwater quality using a coupled modeling system

    Science.gov (United States)

    This study demonstrates the value of a coupled chemical transport modeling system for investigating groundwater nitrate contamination responses associated with nitrogen (N) fertilizer application and increased corn production. The coupled Community Multiscale Air Quality Bidirect...

  17. Recommended Henry’s Law Constants for Non-Groundwater Pathways Models in GoldSim

    Energy Technology Data Exchange (ETDEWEB)

    Dyer, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-06-20

    This memorandum documents the source and numerical value of Henry’s law constants for volatile radionuclides of interest used in the non-groundwater (air and radon) pathways models for the 2018 E-Area Performance Assessment.

  18. A Holistic Assessment of the Sustainability of Groundwater Resources in the North China Plain

    Science.gov (United States)

    Cao, G.; Zheng, C.; Liu, J.; Li, W.

    2010-12-01

    The North China Plain (NCP) is one of the most important agricultural and economic regions of China and also one of the most densely populated in the world (~ 900 people/km2). In recent years, groundwater provides ~ 70% of the total water supply to support grain production, rapid economic development and population growth. Analysis of historical groundwater level contour maps and more than 230 monitoring well time series across the NCP shows a general long-term trend of depletion in groundwater storage in both shallow unconfined and deep confined aquifer zones. Groundwater depletion in the NCP has adversely affected the environment and ecosystems, including drying-up of rivers, land subsidence, seawater intrusion, and groundwater quality deterioration. The volume of groundwater depleted from the aquifer has been estimated from groundwater level fluctuation data by directly integrating the groundwater level change and specific yield across the NCP. The estimated amount of annual groundwater storage change based on this method is ~4 billion m3. A numerical groundwater flow model has been developed for the entire Quaternary aquifer of the NCP and is reasonably well calibrated for both the predevelopment period (1960s) and post-development conditions over the past 40 years. The output of the groundwater model provides estimates of groundwater depletion rates over the post-development period, and the model-calculated storage variation is consistent with the amount determined from groundwater level fluctuation data independent of the model. Moreover, the mean annual total recharge calibrated through the groundwater model is ~120 mm, which is in reasonable agreement with previously reported values based on the water balance method. The groundwater storage depletion derived either from the groundwater level fluctuation data or from the numerical simulation model is highly correlated with spatially averaged precipitation. The model simulations indicate that a decrease in

  19. Limits to Global Groundwater Consumption

    Science.gov (United States)

    Graaf, I. D.; Van Beek, R.; Sutanudjaja, E.; Wada, Y.; Bierkens, M. F.

    2015-12-01

    In regions with frequent water stress and large aquifer systems, groundwater is often used as an additional fresh water source. For many regions of the world groundwater abstraction exceeds groundwater recharge and persistent groundwater depletion occurs. The most direct effect of groundwater depletion is declining of water tables, leading to reduced groundwater discharge needed to sustain base-flow to e.g. rivers. Next to that, pumping costs increase, wells dry up and land subsidence occurs. These problems are expected to increase in the near future due to growing population and climate changes. This poses the urgent question of what the limits are of groundwater consumption worldwide. We simulate global water availability (5 arc-minute resolution, for 1960-2050) using the hydrological model PCR-GLOBWB (van Beek et al. 2011), coupled to a groundwater model based on MODFLOW (de Graaf et al. 2015), allowing for groundwater - surface water interactions. The groundwater model includes a parameterization of world's confined and unconfined aquifer systems needed for a realistic simulation of groundwater head dynamics. Water demands are included (from Wada et al. 2014). We study the limits to water consumption, focusing on locally attainable groundwater and groundwater levels critical to rivers to sustain low flows. We show an increasing trend (1960-2050) in groundwater head declines, due to increase in groundwater demand. Also, stream flow will decrease and low flow conditions will occur more frequent and will be longer in duration in the near future, especially for irrigated areas. Next to that, we provide a global overview of the years it takes until groundwater gets unattainable for e.g. a local farmer (100 m below land-surface used as a proxy), and estimate the increase in pumping cost for the near future. The results show where and when limits of groundwater consumption are reached globally.

  20. Case studies illustrating in-situ remediation methods for soil and groundwater contaminated with petrochemicals

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, Robert A.; Lance, P.E.; Downs, A.; Kier, Brian P. [EMCON Northwest Inc., Portland, OR (United States)

    1993-12-31

    Four case studies of successful in-situ remediation are summarized illustrating cost-effective methods to remediate soil and groundwater contaminated with volatile and non-volatile petrochemicals. Each site is in a different geologic environment with varying soil types and with and without groundwater impact. The methods described include vadose zone vapor extraction, high-vacuum vapor extraction combined with groundwater tab.le depression, air sparging with groundwater recovery and vapor extraction, and bio remediation of saturated zone soils using inorganic nutrient and oxygen addition

  1. DS796 California Groundwater Units

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The California Groundwater Units dataset classifies and delineates the State into one of three groundwater based polygon units: (1) those areas defined as alluvial...

  2. Energy-saving Management of Air Conditioning System of Anhui Post and Telecom Building%安徽邮电大厦中央空调系统节能管理

    Institute of Scientific and Technical Information of China (English)

    王冰凌; 孙克飞

    2009-01-01

    文章介绍了安徽邮电大厦空调系统在末端空调设备、冷却水泵变频改造、制冷机运行控制和空调系统季节转换等方面采取的节能管理措施,相关实践和运行结果表明,加强公共建筑空调系统的运行管理是实现公共建筑节能切实可行的措施.%The paper introduces energy-saving measures that are adopted in the air conditioning system of Anhui Post and Telecom Building in terms of the frequency conversion transformation of air conditioner and cooling water pump, operational control of refrigerating machine and seasonal adjustment d the sys-tem. Practice indicates that it's a feasible way to realize energy efficiency of public building by strengthening energy-saving management of the air conditioning system.

  3. Tehran Groundwater Chemical Pollution

    Directory of Open Access Journals (Sweden)

    M- Shariatpanahi

    1990-06-01

    Full Text Available Seventy eight wells water sample of Tehran plain were examined to determine r its groundwaters chemical pollution. Tehran s groundwaters are slightly acidic and their total dissolved solids are high and are in the hard water category."nThe nitrate concentration of wells water of west region is less than per¬missible level of W.H.O. standard, whereas, the nitrate concentration of some of the other regions wells exceed W.H.O. standard which is indication of pollution"nwith municipal wastewaters. The concentration of toxic elements Cr, Cd, As, Hg and"ni Pb of some of the west, east and south regions wells of Tehran is more than per¬missible level of W.H.O. standard, whereas, the concentration of Cu, Zn,Mn and detergents is below W.H.O. standard."n1"nIn general, the amount of dissolved materials of Tehran s groundwaters and also"ni the potential of their contamination with nitrate is increased as Tehran s ground-"nwaters move further to the south, and even though, Tehran s groundwaters contamination with toxic elements is limited to the industrial west district, industrial-residential east and south districts, but»with regard to the disposal methods of"nt municipal and industrial wastewaters, if Tehran s groundwaters pollution continues,"nlocal contamination of groundwaters is likely to spread. So that finally their quality changes in such a way that this water source may become unfit for most domestic, industrial and agricultural uses. This survey shows the necessity of collection and treatment of Tehran s wastewaters and Prevention of the disposal of untreated wastewaters into the environment.

  4. In situ groundwater bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, Terry C.

    2009-02-01

    In situ groundwater bioremediation of hydrocarbons has been used for more than 40 years. Most strategies involve biostimulation; however, recently bioaugmentation have been used for dehalorespiration. Aquifer and contaminant profiles are critical to determining the feasibility and strategy for in situ groundwater bioremediation. Hydraulic conductivity and redox conditions, including concentrations of terminal electron acceptors are critical to determine the feasibility and strategy for potential bioremediation applications. Conceptual models followed by characterization and subsequent numerical models are critical for efficient and cost effective bioremediation. Critical research needs in this area include better modeling and integration of remediation strategies with natural attenuation.

  5. Groundwater: A Community Action Guide.

    Science.gov (United States)

    Boyd, Susan, Ed.; And Others

    Designed to be a guide for community action, this booklet examines issues and trends related to groundwater contamination. Basic concepts about groundwater and information about problems affecting it are covered under the categories of (1) what is groundwater? (2) availability and depletion; (3) quality and contamination; (4) public health…

  6. Groundwater: A Community Action Guide.

    Science.gov (United States)

    Boyd, Susan, Ed.; And Others

    Designed to be a guide for community action, this booklet examines issues and trends related to groundwater contamination. Basic concepts about groundwater and information about problems affecting it are covered under the categories of (1) what is groundwater? (2) availability and depletion; (3) quality and contamination; (4) public health…

  7. Impact of Preservation of Subsoil Water Act on Groundwater Depletion: The Case of Punjab, India

    Science.gov (United States)

    Tripathi, Amarnath; Mishra, Ashok K.; Verma, Geetanjali

    2016-07-01

    Indian states like Punjab and Haryana, epicenters of the Green Revolution, are facing severe groundwater shortages and falling water tables. Recognizing it as a serious concern, the Government of Punjab enacted the Punjab Preservation of Subsoil Water Act in 2009 (or the 2009 act) to slow groundwater depletion. The objective of this study is to assess the impact of this policy on groundwater depletion, using panel data from 1985 to 2011. Results from this study find a robust effect of the 2009 act on reducing groundwater depletion. Our models for pre-monsoon, post-monsoon, and overall periods of analysis find that since implementation of the 2009 act, groundwater tables have improved significantly. Second, our study reveals that higher shares of tube wells per total cropped area and increased population density have led to a significant decline in the groundwater tables. On the other hand, rainfall and the share of area irrigated by surface water have had an augmenting effect on groundwater resources. In the two models, pre-monsoon and post-monsoon, this study shows that seasonality plays a key role in determining the groundwater table in Punjab. Specifically, monsoon rainfall has a very prominent impact on groundwater.

  8. Radiogenic and Stable Isotope and Hydrogeochemical Investigation of Groundwater, Pajarito Plateau and Surrounding Areas, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Patrick Longmire, Michael Dale, Dale Counce, Andrew Manning, Toti Larson, Kim Granzow, Robert Gray, and Brent Newman

    2007-07-15

    From October 2004 through February 2006, Los Alamos National Laboratory, the New Mexico Environment Department-Department of Energy Oversight Bureau, and the United States Geological Survey conducted a hydrochemical investigation. The purpose of the investigation was to evaluate groundwater flow paths and determine groundwater ages using tritium/helium-3 and carbon-14 along with aqueous inorganic chemistry. Knowledge of groundwater age and flow paths provides a technical basis for selecting wells and springs for monitoring. Groundwater dating is also relevant to groundwater resource management, including aquifer sustainability, especially during periods of long-term drought. At Los Alamos, New Mexico, groundwater is either modern (post-1943), submodern (pre-1943), or mixed (containing both pre- and post-1943 components). The regional aquifer primarily consists of submodern groundwater. Mixed-age groundwater results from initial infiltration of surface water, followed by mixing with perched alluvial and intermediate-depth groundwater and the regional aquifer. No groundwater investigation is complete without using tritium/helium-3 and carbon-14 dating methods to quantify amounts of modern, mixed, and/or submodern components present in samples. Computer models of groundwater flow and transport at Los Alamos should be calibrated to groundwater ages for perched intermediate zones and the regional aquifer determined from this investigation. Results of this study clearly demonstrate the occurrence of multiple flow paths and groundwater ages occurring within the Sierra de los Valles, beneath the Pajarito Plateau, and at the White Rock Canyon springs. Localized groundwater recharge occurs within several canyons dissecting the Pajarito Plateau. Perched intermediate-depth groundwater and the regional aquifer beneath Pueblo Canyon, Los Alamos Canyon, Sandia Canyon, Mortandad Canyon, Pajarito Canyon, and Canon de Valle contain a modern component. This modern component consists

  9. Site scale groundwater flow in Haestholmen

    Energy Technology Data Exchange (ETDEWEB)

    Loefman, J. [VTT Energy, Espoo (Finland)

    1999-05-01

    Groundwater flow modelling on the site scale has been an essential part of site investigation work carried out at different locations since 1986. The objective of the modelling has been to provide results that characterise the groundwater flow conditions deep in the bedrock. The main result quantities can be used for evaluation of the investigation sites and of the preconditions for safe final disposal - of spent nuclear fuel. This study represents the groundwater flow modelling at Haestholmen, and it comprises the transient flow analysis taking into account the effects of density variations and the repository as well as the post-glacial land uplift. The analysis is performed by means of numerical finite element simulation of coupled and transient groundwater flow and solute transport carried out up to 10000 years into the future. This work provides also the results for the site-specific data needs for the block scale groundwater flow modelling at Haestholmen. Conceptually the fractured bedrock is divided into hydraulic units: the planar fracture zones and the remaining part of the bedrock. The equivalent-continuum (EC) model is applied so that each hydraulic unit is treated as a homogeneous and isotropic continuum with representative average characteristics. All the fracture zones are modelled explicitly and represented by two-dimensional finite elements. A site-specific simulation model for groundwater flow and solute transport is developed on the basis of the latest hydrogeological and hydrogeochemical field investigations at Haestholmen. The present topography together with a mathematical model describing the land uplift at the Haestholmen area are employed as a boundary condition at the surface of the model. The overall flow pattern is mostly controlled by the local variations in the topography and by the highly transmissive fracture zones. Near the surface the flow spreads out to offshore and to the lower areas of topography in all directions away from

  10. Utilisation de la post-décharge d'un plasma micro-ondes d'air ou d'azote pour valoriser le méthane

    Science.gov (United States)

    Oumghar, A.; Legrand, J. C.; Diamy, A. M.; Turillon, N.; Ben-Aïm, R. I.

    1994-01-01

    Valorization of methane is obtained by means of the reaction with a plasma. The plasma is produced in a quartz tube (30 mm in diameter) crossing a wave guide. The energy is supplied by a generator (Thomson CSF, 2 450 MHz, 15 to 1 500 W). Directional couplers followed by an attenuator and thermistor detectors enable forward Pi_i and reflected Pi_r power to be measured. Methane is introduced in the post-discharge zone through five tubes symmetrically arranged around the reactor. Methane consumption α, selectivity SX and yield RX are measured as a function of the following parameters : β methane/air ratio, F gaz flow, d distance where methane is introduced in the plasma, P pressure, Pi microwave power absorbed by air or nitrogen. It appears that acetylene is the major hydrocarbon obtained. The corresponding selectivity is increased when Pi and P are increased or when d and F are decreased. The optimum value of β is 4/5. If the best experimental conditions are selected, selectivity of total C2 reaches 44 % with a conversion ratio of 80 %. By decreasing methane/air ratio, carbon monoxide yield is increased. The ratio acetylene/ethylene can by varied without changing the conversion ratio, by introducing a catalyst in the post reaction zone. La valorisation du méthane est réalisée dans la post-décharge d'un plasma microondes (2 450 MHz) d'air ou d'azote. Lorsque la décharge est produite dans l'azote, les principaux produits dosés sont l'acétylène, l'éthylène, l'éthane et l'hydrogène. Lorsque la décharge est produite dans l'air, on dose en outre le monoxyde de carbone. Le taux de conversion du méthane ainsi que la sélectivité des produits ont été déterminés en fonction des paramètres expérimentaux suivants : proportion méthane/gaz plasmagène, flux gazeux, distance d'introduction du méthane dans la post-décharge, pression et puissance micro-ondes. Le procédé expérimenté permet d'obtenir des rendements chimiques importants et d'éviter la

  11. PATHS groundwater hydrologic model

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, R.W.; Schur, J.A.

    1980-04-01

    A preliminary evaluation capability for two-dimensional groundwater pollution problems was developed as part of the Transport Modeling Task for the Waste Isolation Safety Assessment Program (WISAP). Our approach was to use the data limitations as a guide in setting the level of modeling detail. PATHS Groundwater Hydrologic Model is the first level (simplest) idealized hybrid analytical/numerical model for two-dimensional, saturated groundwater flow and single component transport; homogeneous geology. This document consists of the description of the PATHS groundwater hydrologic model. The preliminary evaluation capability prepared for WISAP, including the enhancements that were made because of the authors' experience using the earlier capability is described. Appendixes A through D supplement the report as follows: complete derivations of the background equations are provided in Appendix A. Appendix B is a comprehensive set of instructions for users of PATHS. It is written for users who have little or no experience with computers. Appendix C is for the programmer. It contains information on how input parameters are passed between programs in the system. It also contains program listings and test case listing. Appendix D is a definition of terms.

  12. GROUNDWATER RECHARGE AND CHEMICAL ...

    Science.gov (United States)

    The existing knowledge base regarding the presence and significance of chemicals foreign to the subsurface environment is large and growing -the papers in this volume serving as recent testament. But complex questions with few answers surround the unknowns regarding the potential for environmental or human health effects from trace levels of xenobiotics in groundwater, especially groundwater augmented with treated wastewater. Public acceptance for direct or indirect groundwater recharge using treated municipal wastewater ( especially sewage) spans the spectrum from unquestioned embrace to outright rejection. In this article, I detour around the issues most commonly discussed for groundwater recharge and instead focus on some of the less-recognized issues- those that emanate from the mysteries created at the many literal and virtual interfaces involved with the subsurface world. My major objective is to catalyze discussion that advances our understanding of the barriers to public acceptance of wastewater reuse -with its ultimate culmination in direct reuse for drinking. I pose what could be a key question as to whether much of the public's frustration or ambivalence in its decision making process for accepting or rejecting water reuse (for various purposes including personal use) emanates from fundamental inaccuracies, misrepresentation, or oversimplification of what water 'is' and how it functions in the environment -just what exactly is the 'water cyc

  13. Regulating groundwater use

    NARCIS (Netherlands)

    Hoogesteger van Dijk, Jaime; Wester, Flip

    2017-01-01

    Around the world it has proven very difficult to develop policies and interventions that ensure socio-environmentally sustainable groundwater use and exploitation. In the state of Guanajuato, Central Mexico, both the national government and the decentralized state government have pursued to regulate

  14. The Continued Need for USAF Light Attack post OEF/OIF: A Survey of West African Infrastructure to Support Tactical Air Operations

    Science.gov (United States)

    2013-04-01

    16 Figure5: Algeria ….…………………………………………………………………………18 Abstract As the USAF transitions to post-OIF/OEF operations there is a continued...Since then AQIM’s area of operation has expanded beyond Algeria to include Mali, Mauritania, Tunisia and Morocco.5 AQIM also operates along the...western boarder of Niger and may have links there to the local Tuareg group Mouvement des Nigerians pour la Justice.6 In 2010 AQIM announced its

  15. Analysis of groundwater anomalies using GRACE over various districts of Jharkhand

    Science.gov (United States)

    Verma, Arpita; Kumar, Anant; Kumar, Sanjay

    2016-05-01

    Groundwater is an important requirement for the massive population of India. Generally the groundwater level is monitored by using monitoring wells. In this study, Gravity Recovery and Climate Experiment (GRACE) Terrestrial Water Storage (TWS), Land surface state variable GLDAS and Soil Moisture (SM) data were tested for estimating ground water information and based on these groundwater assessments were carried out over the years 2003 to 2012 for Jharkhand State. Additionally, Tropical Rainfall Measuring Mission (TRMM) accumulated rainfall data was also used for the year's 2008 to 2012.From the study over 120 months span of various districts the maximum depletion in storage of groundwater averaged over the six districts is +/-5cm/yr in the year 2010 and maximum storage year (in term of Equivalent water thickness) groundwater average over the six districts is +/-4.4cm in the year 2003. The study also utilized ground based Seasonal changes in the groundwater resource over 287 monitoring wells and estimated groundwater data using map analysis over Jharkhand. This study analyzed seasonal water level variations based on groundwater anomaly. Remote sensing generated result compared with well data shows R2 = 0.6211 and RMSE = 39.46 cm at average seasonal cycle. Also information of different time periods of rainfall (i.e., pre-monsoon and post-monsoon) was analyzed. The trend analysis of rainfall and estimated groundwater gives the basic knowledge that groundwater storage loss and gain showed similarities with increase and decrease in rainfall.

  16. Tracing and quantifying groundwater inflow into lakes using radon-222

    Directory of Open Access Journals (Sweden)

    T. Kluge

    2007-06-01

    Full Text Available Due to its high activities in groundwater, the radionuclide 222Rn is a sensitive natural tracer to detect and quantify groundwater inflow into lakes, provided the comparatively low activities in the lakes can be measured accurately. Here we present a simple method for radon measurements in the low-level range down to 3 Bq m−3, appropriate for groundwater-influenced lakes, together with a concept to derive inflow rates from the radon budget in lakes. The analytical method is based on a commercially available radon detector and combines the advantages of established procedures with regard to efficient sampling and sensitive analysis. Large volume (12 l water samples are taken in the field and analyzed in the laboratory by equilibration with a closed air loop and alpha spectrometry of radon in the gas phase. After successful laboratory tests, the method has been applied to a small dredging lake without surface in- or outflow in order to estimate the groundwater contribution to the hydrological budget. The inflow rate calculated from a 222Rn balance for the lake is around 530 m3 per day, which is comparable to the results of previous studies. In addition to the inflow rate, the vertical and horizontal radon distribution in the lake provides information on the spatial distribution of groundwater inflow to the lake. The simple measurement and sampling technique encourages further use of radon to examine groundwater-lake interaction.

  17. Reliable groundwater levels: failures and lessons learned from modeling and monitoring studies

    Science.gov (United States)

    Van Lanen, Henny A. J.

    2017-04-01

    Adequate management of groundwater resources requires an a priori assessment of impacts of intended groundwater abstractions. Usually, groundwater flow modeling is used to simulate the influence of the planned abstraction on groundwater levels. Model performance is tested by using observed groundwater levels. Where a multi-aquifer system occurs, groundwater levels in the different aquifers have to be monitored through observation wells with filters at different depths, i.e. above the impermeable clay layer (phreatic water level) and beneath (artesian aquifer level). A reliable artesian level can only be measured if the space between the outer wall of the borehole (vertical narrow shaft) and the observation well is refilled with impermeable material at the correct depth (post-drilling phase) to prevent a vertical hydraulic connection between the artesian and phreatic aquifer. We were involved in improper refilling, which led to impossibility to monitor reliable artesian aquifer levels. At the location of the artesian observation well, a freely overflowing spring was seen, which implied water leakage from the artesian aquifer affected the artesian groundwater level. Careful checking of the monitoring sites in a study area is a prerequisite to use observations for model performance assessment. After model testing the groundwater model is forced with proposed groundwater abstractions (sites, extraction rates). The abstracted groundwater volume is compensated by a reduction of groundwater flow to the drainage network and the model simulates associated groundwater tables. The drawdown of groundwater level is calculated by comparing the simulated groundwater level with and without groundwater abstraction. In lowland areas, such as vast areas of the Netherlands, the groundwater model has to consider a variable drainage network, which means that small streams only carry water during the wet winter season, and run dry during the summer. The main streams drain groundwater

  18. The distribution and sea-air transfer of volatile mercury in waste post-desulfurization seawater discharged from a coal-fired power plant.

    Science.gov (United States)

    Sun, Lumin; Lin, Shanshan; Feng, Lifeng; Huang, Shuyuan; Yuan, Dongxing

    2013-09-01

    The waste seawater discharged in coastal areas from coal-fired power plants equipped with a seawater desulfurization system might carry pollutants such as mercury from the flue gas into the adjacent seas. However, only very limited impact studies have been carried out. Taking a typical plant in Xiamen as an example, the present study targeted the distribution and sea-air transfer flux of volatile mercury in seawater, in order to trace the fate of the discharged mercury other than into the sediments. Samples from 28 sampling sites were collected in the sea area around two discharge outlets of the plant, daily and seasonally. Total mercury, dissolved gaseous mercury and dissolved total mercury in the seawater, as well as gaseous elemental mercury above the sea surface, were investigated. Mean concentrations of dissolved gaseous mercury and gaseous elemental mercury in the area were 183 and 4.48 ng m(-3) in summer and 116 and 3.92 ng m(-3) in winter, which were significantly higher than those at a reference site. Based on the flux calculation, the transfer of volatile mercury was from the sea surface into the atmosphere, and more than 4.4 kg mercury, accounting for at least 2.2 % of the total discharge amount of the coal-fired power plant in the sampling area (1 km(2)), was emitted to the air annually. This study strongly suggested that besides being deposited into the sediment and diluted with seawater, emission into the atmosphere was an important fate for the mercury from the waste seawater from coal-fired power plants.

  19. A post-occupancy monitored evaluation of the dimmable lighting, automated shading, and underfloor air distribution system in The New York Times Building

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eleanor S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fernandes, Luis L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Coffey, Brian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); McNeil, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Clear, Robert [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Webster, Tom [Univ. of California, Berkeley, CA (United States); Bauman, Fred [Univ. of California, Berkeley, CA (United States); Dickerhoff, Darryl [Univ. of California, Berkeley, CA (United States); Heinzerling, David [Univ. of California, Berkeley, CA (United States); Hoyt, Tyler [Univ. of California, Berkeley, CA (United States)

    2013-01-01

    With aggressive goals to reduce national energy use and carbon emissions, the US Department of Energy will be looking to exemplary buildings that have already invested in new approaches to achieving the energy performance goals now needed at a national level. The New York Times Building, in New York, New York, incorporates a number of innovative technologies, systems and processes and could become a model for widespread replication in new and existing buildings. Post-occupancy data are invaluable in establishing confidence in innovation. A year-long monitored study was conducted to verify energy performance, assess occupant comfort and satisfaction with the indoor environment, and evaluate impacts on maintenance and operations. Lessons learned were derived from the analysis; these lessons could help identify and shape policy, financial, or supporting strategies to accelerate diffusion in the commercial building market.

  20. Environmental Sciences Division Groundwater Program Office. Annual report, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-30

    This first edition of the Martin Marietta Energy Systems, Inc., (Energy Systems) Groundwater Program Annual Report summarizes the work carried out by the Energy Systems GWPO for fiscal year (FY) 1993. This introductory section describes the GWPO`s staffing, organization, and funding sources. The GWPO is responsible for coordination and oversight for all components of the groundwater program at the three Oak Ridge facilities [ORNL, the Oak Ridge Y-12 Plant, and the Oak Ridge K-25 Site], and the PGDP and PORTS, respectively. Several years ago, Energy systems senior management recognized that the manner in which groundwater activities were conducted at the five facilities could result in unnecessary duplication of effort, inadequate technical input to decisions related to groundwater issues, and could create a perception within the regulatory agencies of a confusing and inconsistent approach to groundwater issues at the different facilities. Extensive interactions among management from Environmental Compliance, Environmental Restoration (ER), Environmental Sciences Division, Environmental Safety and Health, and the five facilities ultimately led to development of a net technical umbrella organization for groundwater. On April 25, 1991, the GWPO was authorized to be set up within ORNL thereby establishing a central coordinating office that would develop a consistent technical and administrative direction for the groundwater programs of all facilities and result in compliance with all relevant U.S. Environmental Protection Agency (EPA) regulations such as RCRA and Comprehensive Environmental Restoration, Compensation and Liability Act (CERCLA) as well as U.S. Department of Energy (DOE) regulations and orders. For example, DOE Order 5400.1, issued on November 9, 1988, called for each DOE facility to develop an environmental monitoring program for all media (e.g., air, surface water, and groundwater).

  1. Groundwater hydrology instructional system

    Science.gov (United States)

    Schmidt, Ronald G.

    Wright State University, Dayton, Ohio, is preparing for its third cycle of the Interactive Remote Instructional System (IRIS) in groundwater hydrology, beginning January 15, 1986. The first cycle finished with an impressive completion ratio for registered participants, and the second cycle has currently been underway since July. This comprehensive hydrogeology program was originally developed for the Soil Conservation Service (of the U.S. Department of Agriculture) to prepare their personnel for professional practice work. Since its evolution into IRIS, an 80% participant completion rate has been recorded for the first cycle, which is a significant departure from success rates traditionally recorded by correspondence courses. This excellent rate of success is the result of 2 years of refinement and demonstrates the progressive nature of the program. IRIS has met the needs of participants by developing a curriculum that reflects current trends in the groundwater industry and has provided a unique educational approach that ensures maximum interaction between the instructional staff and participants.

  2. Contain contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Mutch, R.D. Jr.; Caputi, J.R. [Eckenfelder, Inc., Mahwah, NJ (United States); Ash, R.E. IV [Eckenfelder Inc., Nashville, TN (United States)

    1997-05-01

    Despite recent progress in innovative treatment technologies, many problems with contaminated groundwater still require the use of barrier walls, typically in combination with extraction and treatment systems. New technologies for subsurface barrier walls, mostly based on geomembranes, advancements in self-hardening slurries and permeation grouts with materials such as colloidal silica gel and montan wax emulsions, are being developed at an unprecedented pace. The paper discusses deep soil mixing, jet grouting, slurry trenches, and permeation grouting.

  3. Aqueous-phase chemistry and bactericidal effects from an air discharge plasma in contact with water: evidence for the formation of peroxynitrite through a pseudo-second-order post-discharge reaction of H2O2 and HNO2

    Science.gov (United States)

    Lukes, P.; Dolezalova, E.; Sisrova, I.; Clupek, M.

    2014-02-01

    The formation of transient species (OH·, NO2·, NO radicals) and long-lived chemical products (O3, H2O2, NO_{3}^{-} , NO_{2}^{-} ) produced by a gas discharge plasma at the gas-liquid interface and directly in the liquid was measured in dependence on the gas atmosphere (20% oxygen mixtures with nitrogen or with argon) and pH of plasma-treated water (controlled by buffers at pH 3.3, 6.9 or 10.1). The aqueous-phase chemistry and specific contributions of these species to the chemical and biocidal effects of air discharge plasma in water were evaluated using phenol as a chemical probe and bacteria Escherichia coli. The nitrated and nitrosylated products of phenol (4-nitrophenol, 2-nitrophenol, 4-nitrocatechol, 4-nitrosophenol) in addition to the hydroxylated products (catechol, hydroquinone, 1,4-benzoquinone, hydroxy-1,4-benzoquinone) evidenced formation of NO2·, NO· and OH· radicals and NO+ ions directly by the air plasma at the gas-liquid interface and through post-discharge processes in plasma-activated water (PAW) mediated by peroxynitrite (ONOOH). Kinetic study of post-discharge evolution of H2O2 and NO_{2}^{-} in PAW has demonstrated excellent fit with the pseudo-second-order reaction between H2O2 and NO_{2}^{-} . The third-order rate constant k = 1.1 × 103 M-2 s-1 for the reaction NO_{2}^{-} +H_{2}O_{2}+H^{+}\\to ONOOH+H_{2}O was determined in PAW at pH 3.3 with the rate of ONOOH formation in the range 10-8-10-9 M s-1. Peroxynitrite chemistry was shown to significantly participate in the antibacterial properties of PAW. Ozone presence in PAW was proved indirectly by pH-dependent degradation of phenol and detection of cis,cis-muconic acid, but contribution of ozone to the inactivation of bacteria by the air plasma was negligible.

  4. Manganese oxide octahedral molecular sieve K-OMS-2 as catalyst in post plasma-catalysis for trichloroethylene degradation in humid air.

    Science.gov (United States)

    Nguyen Dinh, M T; Giraudon, J-M; Vandenbroucke, A M; Morent, R; De Geyter, N; Lamonier, J-F

    2016-08-15

    The total oxidation of trichloroethylene (TCE) in air at low relative humidity (RH=10%) in the presence of CO2 (520ppmv) was investigated in function of energy density using an atmospheric pressure negative DC luminescent glow discharge combined with a cryptomelane catalyst positioned downstream of the plasma reactor at a temperature of 150°C. When using Non-Thermal Plasma (NTP) alone, it is found a low COx (x=1-2) yield in agreement with the detection of gaseous polychlorinated by-products in the outlet stream as well as ozone which is an harmful pollutant. Introduction of cryptomelane enhanced trichloroethylene removal, totally inhibited plasma ozone formation and increased significantly the COx yield. The improved performances of the hybrid system were mainly ascribed to the total destruction of plasma generated ozone on cryptomelane surface to produce active oxygen species. Consequently these active oxygen species greatly enhanced the abatement of the plasma non-reacted TCE and completely destroyed the hazardous plasma generated polychlorinated intermediates. The facile redox of Mn species associated with oxygen vacancies and mobility as well as the textural properties of the catalyst might also contribute as a whole to the efficiency of the process.

  5. Positive and negative impacts of five Austrian gravel pit lakes on groundwater quality.

    Science.gov (United States)

    Muellegger, Christian; Weilhartner, Andreas; Battin, Tom J; Hofmann, Thilo

    2013-01-15

    Groundwater-fed gravel pit lakes (GPLs) affect the biological, organic, and inorganic parameters of inflowing groundwater through combined effects of bank filtration at the inflow, reactions within the lake, and bank filtration at the outflow. GPLs result from wet dredging for sand and gravel and may conflict with groundwater protection programs by removing the protective soil cover and exposing groundwater to the atmosphere. We have investigated the impact on groundwater of five GPLs with different sizes, ages, and mean residence times, and all having low post-excavation anthropogenic usage. The results revealed highly active biological systems within the lake water, in which primary producers significantly reduced inflowing nitrate concentrations. Decalcification also occurred in lake water, reducing water hardness, which could be beneficial for waterworks in hard groundwater areas. Downgradient groundwater nitrate and calcium concentrations were found to be stable, with only minor seasonal variations. Biological degradation of organic material and organic micropollutants was also observed in the GPLs. For young GPLs adequate sediment deposits may not yet have formed and degradation processes at the outflow may consequently not yet be well established. However, our results showed that within 5 years from the cessation of excavation a protective sediment layer is established that is sufficient to prevent the export of dissolved organic carbon to downgradient groundwater. GPLs can improve groundwater quality in anthropogenically (e.g., pesticides and nitrate) or geologically (e.g., hardness) challenging situations. However, post-excavation usage of GPLs is often dominated by human activities such as recreational activities, water sports, or fish farming. These activities will affect lake and groundwater quality and the risks involved are difficult to predict and monitor and can lead to overall negative impacts on groundwater quality. Copyright © 2012 Elsevier B

  6. Air stripping. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The bibliography contains citations concerning the application of air stripping techniques to water treatment, including groundwater decontamination and wastewater purification. The advantages and disadvantages of air stripping over other water treatment processes are discussed. Cleanup of the organic emissions generated by air stripping is also considered. The primary applications of air stripping are in groundwater and soil cleanup. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  7. GROUNDWATER PROTECTION MANAGEMENT PROGRAM DESCRIPTION.

    Energy Technology Data Exchange (ETDEWEB)

    PAQUETTE,D.E.; BENNETT,D.B.; DORSCH,W.R.; GOODE,G.A.; LEE,R.J.; KLAUS,K.; HOWE,R.F.; GEIGER,K.

    2002-05-31

    THE DEPARTMENT OF ENERGY ORDER 5400.1, GENERAL ENVIRONMENTAL PROTECTION PROGRAM, REQUIRES THE DEVELOPMENT AND IMPLEMENTATION OF A GROUNDWATER PROTECTION PROGRAM. THE BNL GROUNDWATER PROTECTION MANAGEMENT PROGRAM DESCRIPTION PROVIDES AN OVERVIEW OF HOW THE LABORATORY ENSURES THAT PLANS FOR GROUNDWATER PROTECTION, MONITORING, AND RESTORATION ARE FULLY DEFINED, INTEGRATED, AND MANAGED IN A COST EFFECTIVE MANNER THAT IS CONSISTENT WITH FEDERAL, STATE, AND LOCAL REGULATIONS.

  8. Groundwater types in Southeast Srem

    Directory of Open Access Journals (Sweden)

    Gregorić Enike

    2009-01-01

    Full Text Available The region of Southeast Srem is rich in ground waters, which is of great significance to agricultural production. The objective of this paper was to designate the zones of different groundwater types from the aspect of recharge, based on the analysis of groundwater regimes in the study area. A very complex groundwater regime in Southeast Srem, which depends on a great number of natural and some anthropogenic factors, makes it difficult to designate clearly the zones of the three main types of groundwater regime. Still, the boundaries of the zones of groundwater regime types were defined based on the results of correlation analysis of the basic factors affecting the groundwater regime. Zone I includes the climatic type of groundwater. Its fluctuation corresponds to the vertical factors of water balance (precipitation and evaporation and it is not affected by the river water level. This zone extends North and East of the line Putinci, Golubinci, Stara Pazova, Batajnica, Dobanovci, mainly in the area of the loess plateau. Within the zone, groundwater is at a relatively great depth. Only exceptionally, in the valleys, it appears almost on the surface. Zone II includes the climatic-hydrological groundwater type, which is the transition between the climatic type and the hydrological type. The fluctuation of groundwater regime is affected both by the effect of vertical balance factors, and by the effect of watercourses. Climatic-hydrological groundwater type covers the central and the lowest part of the study area and the South part of the middle terrace. Zone III is classified as the hydrological groundwater type and it covers the riparian areas along the Sava and the Danube. The aquifer is hydraulically connected with the river Sava.

  9. SPECIFIC SOLUTIONS GROUNDWATER FLOW EQUATION

    OpenAIRE

    Syahruddin, Muhammad Hamzah

    2014-01-01

    Geophysic publication Groundwater flow under surface, its usually slow moving, so that in laminer flow condition can find analisys using the Darcy???s law. The combination between Darcy law and continuity equation can find differential Laplace equation as general equation groundwater flow in sub surface. Based on Differential Laplace Equation is the equation that can be used to describe hydraulic head and velocity flow distribution in porous media as groundwater. In the modeling Laplace e...

  10. Impact of groundwater use as heat energy on coastal ecosystem and fisheries

    Science.gov (United States)

    Taniguchi, Makoto

    2016-04-01

    Demands for groundwater as a heat energy source to melt snow is increasing in many coastal snowy areas in Japan because of the lack of laborers for snow removal and the abundance of groundwater resources. The temperature of groundwater is relatively higher in winter than that of the air and river water, therefore it is a useful heat source to melt snow. However, groundwater is also beneficial for the coastal ecosystem and fishery production because of the nutrient discharge by submarine groundwater discharge (SGD), which is one of the water and dissolved material pathways from land to the ocean. Therefore, groundwater is involved in the tradeoff and management conflict existing between energy and food (fisheries). In this study, the impact of groundwater, used as a heat energy source for the melting of snow accumulated on roads, on the coastal ecosystem and fisheries has been analyzed in the snowy areas of Obama City, Fukui Prefecture, Japan. Positive correlation has been found between primary production rates in Obama Bay and radon concentrations which show the magnitude of the submarine groundwater discharge. Therefore, the increase in groundwater pumping on land reduces fishery production in the ocean. Results of 3D numerical simulations of the basin scale groundwater model show a reduction of SGD by 5 percent due to an increase in groundwater pumping by 1.5 times. This reduction of SGD caused a 3.7 ton decrease in fishery production under the aforementioned assumptions. The groundwater-energy-fishery nexus was found in Obama Bay, Japan and the tradeoff between water and food was evaluated.

  11. The groundwater subsidy to vegetation: groundwater exchanges between landcover patches

    Science.gov (United States)

    Steven, L. I.; Gimenez, R.; Jobbagy, E. G.

    2015-12-01

    The Gran Chaco is a hot, dry plain, that spans over 60 million hectares across Bolivia, Paraguay, Brazil and Argentina. It supports high biodiversity in its dry forest and savannahs, but is rapidly being converted to agriculture in response to growing soy demand and technology including genetic modification and zero-till, that has made cultivation in drier landscapes more viable. Under natural conditions, the deep-rooted, native vegetation of the Chaco effectively captured all rainfall for evapotranspiration resulting in near zero groundwater recharge under the dry forest. Conversion to shallower rooted soy and corn, combined with the fallow period prior to the growing season, reduces evapotranspiration and allows some water to percolate through the root zone and recharge the groundwater system. When this groundwater recharge occurs, it creates groundwater mounding and a hydraulic gradient that drives flow to adjacent landcover patches where recharge does not occur. As the watertable rises, groundwater becomes available to the deep-rooted, dry forest vegetation. We develop a soil and groundwater flow model to simulate infiltration, percolation, evaporation, rootwater uptake, groundwater recharge and the lateral transfer of water between adjacent landcover patches to quantify this groundwater subsidy from converted agricultural lands to remnant patches of dry forest.

  12. Solutions Remediate Contaminated Groundwater

    Science.gov (United States)

    2010-01-01

    During the Apollo Program, NASA workers used chlorinated solvents to clean rocket engine components at launch sites. These solvents, known as dense non-aqueous phase liquids, had contaminated launch facilities to the point of near-irreparability. Dr. Jacqueline Quinn and Dr. Kathleen Brooks Loftin of Kennedy Space Center partnered with researchers from the University of Central Florida's chemistry and engineering programs to develop technology capable of remediating the area without great cost or further environmental damage. They called the new invention Emulsified Zero-Valent Iron (EZVI). The groundwater remediation compound is cleaning up polluted areas all around the world and is, to date, NASA's most licensed technology.

  13. Tracer attenuation in groundwater

    Science.gov (United States)

    Cvetkovic, Vladimir

    2011-12-01

    The self-purifying capacity of aquifers strongly depends on the attenuation of waterborne contaminants, i.e., irreversible loss of contaminant mass on a given scale as a result of coupled transport and transformation processes. A general formulation of tracer attenuation in groundwater is presented. Basic sensitivities of attenuation to macrodispersion and retention are illustrated for a few typical retention mechanisms. Tracer recovery is suggested as an experimental proxy for attenuation. Unique experimental data of tracer recovery in crystalline rock compare favorably with the theoretical model that is based on diffusion-controlled retention. Non-Fickian hydrodynamic transport has potentially a large impact on field-scale attenuation of dissolved contaminants.

  14. Permafrost thaw in a nested groundwater-flow system

    Science.gov (United States)

    McKenzie, Jeffery M.; Voss, Clifford I.

    2013-01-01

    Groundwater flow in cold regions containing permafrost accelerates climate-warming-driven thaw and changes thaw patterns. Simulation analyses of groundwater flow and heat transport with freeze/thaw in typical cold-regions terrain with nested flow indicate that early thaw rate is particularly enhanced by flow, the time when adverse environmental impacts of climate-warming-induced permafrost loss may be severest. For the slowest climate-warming rate predicted by the Intergovernmental Panel on Climate Change (IPCC), once significant groundwater flow begins, thick permafrost layers can vanish in several hundred years, but survive over 1,000 years where flow is minimal. Large-scale thaw depends mostly on the balance of heat advection and conduction in the supra-permafrost zone. Surface-water bodies underlain by open taliks allow slow sub-permafrost flow, with lesser influence on regional thaw. Advection dominance over conduction depends on permeability and topography. Groundwater flow around permafrost and flow through permafrost impact thaw differently; the latter enhances early thaw rate. Air-temperature seasonality also increases early thaw. Hydrogeologic heterogeneity and topography strongly affect thaw rates/patterns. Permafrost controls the groundwater/surface-water-geomorphology system; hence, prediction and mitigation of impacts of thaw on ecology, chemical exports and infrastructure require improved hydrogeology/permafrost characterization and understanding

  15. Sustainable groundwater management in California

    Science.gov (United States)

    Phillips, Steven P.; Rogers, Laurel Lynn; Faunt, Claudia

    2015-12-01

    The U.S. Geological Survey (USGS) uses data collection, modeling tools, and scientific analysis to help water managers plan for, and assess, hydrologic issues that can cause “undesirable results” associated with groundwater use. This information helps managers understand trends and investigate and predict effects of different groundwater-management strategies.

  16. Promoting local management in groundwater

    Science.gov (United States)

    van Steenbergen, Frank

    2006-03-01

    There is a strong case for making greater effort to promote local groundwater management—in addition to other measures that regulate groundwater use. Though scattered, there are several examples—from India, Pakistan, Yemen and Egypt—where groundwater users effectively self-imposed restrictions on the use of groundwater. There are a number of recurrent themes in such spontaneously-developed examples of local regulation: the importance of not excluding potential users; the importance of simple, low transaction cost rules; the power of correct and accessible hydrogeological information; the possibility of making more use of demand and supply management strategies; and the important supportive role of local governments. The case is made, using examples, for actively promoting local groundwater management as an important element in balancing groundwater uses. Two programmes for promoting local groundwater management in South India are described—one focussing on participatory hydrological monitoring, and one focussing on micro-resource planning and training. In both cases the response was very positive and the conclusion is that promoting local groundwater regulation is not difficult, costly or sensitive and can reach the necessary scale quickly.

  17. Accuracy of seven vapour intrusion algorithms for VOC in groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Provoost, Jeroen; Bronders, Jan; Seuntjens, Piet [Flemish Inst. for Technological Research (VITO), Mol (Belgium); Reijnders, Lucas [Dept. of Science, Open Univ. Netherlands (OU NL), Heerlen (Netherlands); Swartjes, Frank; Lijzen, Johannes [National Inst. for Public Health and the Environment (RIVM), Bilthoven (Netherlands)

    2009-02-15

    During the last decade, soil contamination with volatile organic contaminants (VOC) received special attention because of their potential to cause indoor air problems. Moreover, research has shown that people spend 64% to 94% of there time indoors; therefore, the indoor air quality is of a primary importance for exposure to VOC. Human health risks to VOC-in cases of soil contamination-are often dominated by the exposure route 'inhalation of indoor air'. Exposure is often a result of vapour transport from the soil or groundwater to the indoor air of the building. Within human health risk assessments, a variety of algorithms are available that calculate transfer of soil gas to the indoor air. These algorithms suffer from a relatively high uncertainty due to a lack of representation of spatial and temporal variability. For such an application, these algorithms need to be further verified empirically against field observations so that they can be sufficiently reliable for regulatory purposes. This paper presents the accuracy for seven algorithms by using observed and predicted soil and indoor air concentrations from three sites, where the groundwater had been contaminated with aromatic and chlorinated VOC. (orig.)

  18. Decadal variations in groundwater quality

    DEFF Research Database (Denmark)

    Jessen, Søren; Postma, Dieke; Thorling, Lærke

    2017-01-01

    Twenty-five years of groundwater quality monitoring in a sandy aquifer beneath agricultural fields showed large temporal and spatial variations in major ion groundwater chemistry, which were linked closely to the nitrate (NO3) content of agricultural recharge. Between 1988 and 2013, the NO3 content...... loading. Agriculture thus is an important determinant of major ion groundwater chemistry. Temporal and spatial variations in the groundwater quality were simulated using a 2D reactive transport model, which combined effects of the historical NO3 leaching and denitrification, with dispersive mixing...... into the pristine groundwater residing deeper in the aquifer. Reactant-to-product ratios across reaction fronts are altered by dispersive mixing and transience in reactant input functions. Modelling therefore allowed a direct comparison of observed and simulated ratios of concentrations of NO3 (reactant...

  19. Study of Seasonal Variation in Groundwater Quality of Sagar City (India) by Principal Component Analysis

    OpenAIRE

    Hemant Pathak; S. N. Limaye

    2011-01-01

    Groundwater is one of the major resources of the drinking water in Sagar city (India.). In this study 15 sampling station were selected for the investigations on 14 chemical parameters. The work was carried out during different months of the pre-monsoon, monsoon and post-monsoon seasons in June 2009 to June 2010. The multivariate statistics such as principal component and cluster analysis were applied to the datasets to investigate seasonal variations in groundwater quality. Principal axis fa...

  20. Artificial recharge of groundwater

    Science.gov (United States)

    The Task Committee on Guidelines for Artificial Recharge of Groundwater, of the American Society of Civil Engineers' (ASCE) Irrigation and Drainage Division, sponsored an International Symposium on Artificial Recharge of Groundwater at the Inn-at-the-Park Hotel in Anaheim, Calif., August 23-27, 1988. Cosponsors were the U.S. Geological Survey, California Department of Water Resources, University of California Water Resources Center, Metropolitan Water District of Southern California, with cooperation from the U.S. Bureau of Reclamation, International Association of Hydrological Sciences, American Water Resources Association, U.S. Agency for International Development, World Bank, United Nations Department of Technical Cooperation for Development, and a number of local and state organizations.Because of the worldwide interest in artificial recharge and the need to develop efficient recharge facilities, the Anaheim symposium brought together an interdisciplinary group of engineers and scientists to provide a forum for many professional disciplines to exchange experiences and findings related to various types of artificial recharge; learn from both successful and unsuccessful case histories; promote technology transfer between the various disciplines; provide an education resource for communication with those who are not water scientists, such as planners, lawyers, regulators, and the public in general; and indicate directions by which cities or other entities can save funds by having reasonable technical guidelines for implementation of a recharge project.

  1. 2007-2011年麻醉恢复室空气监测结果分析%Analysis of results of air monitoring in post anesthesia care unit between 2007 and 2011

    Institute of Scientific and Technical Information of China (English)

    唐芳; 蔡建芬

    2013-01-01

    OBJECTIVE To retrospectively analyze the results of the air testing in the post anesthesia care unit (PACU) from 2007 to 2011 so as to explore the impact of the air quality on the incidence of such complication as the infections during the recovery from anesthesia. METHODS The air in the PACU was disinfected in accordance with the rules and regulations, the temperature in the room maintained between 22 ℃ and 25 ℃, with the relative humidity varying from 40% to 60%. The air samples on the tablet were cultured in the incubator, and the bacterial identification was performed by French BioMerieux VITEK microbial identification system. RESULTS A total of 300 samples were expected to be investigated, and 278 samples were actually investigated, accounting for 92.67%, among which there were 110 sterile samples, 134 samples with the bacterial colony count below 200 CFU/m3 , 24 samples with the bacterial colony counts ranging from 200 CFU/m3 to 500 CFU/m3 , and 10 samples with the bacterial colony count above 500 CFU/m3 , with the mean bacterial colony count of (86. 2±33. 8) CFU/ m3. A total of 175 strains of pathogens were isolated, and the Staphylococcus aureus , Staphylococcus epidermidis and Pseudomonas aeruginosa were the three species of predominant pathogens, accounting for 30. 29% , 20. 57% , and 16. 57%, respectively. CONCLUSION The air quality is relatively stable in the PACU during 2007 - 2011, however, the microbial contamination remains serious, thus the disinfection and isolation system should be made sound so as to reduce the incidence of infections.%目的 回顾性分析2007-2011年麻醉恢复室的空气检测结果,探讨麻醉恢复室空气质量对麻醉恢复期患者发生感染等并发症的影响.方法 依据麻醉恢复室的规章制度进行空气消毒,室内温度保持在22~25℃,相对湿度在40%60%,将采集好空气样本的平板置于培养箱中进行培养,细菌鉴定采用法国生物梅里埃公司

  2. Tuning the target composition of amine-grafted CPO-27-Mg for capture of CO2 under post-combustion and air filtering conditions: a combined experimental and computational study.

    Science.gov (United States)

    Bernini, M C; García Blanco, A A; Villarroel-Rocha, J; Fairen-Jimenez, D; Sapag, K; Ramirez-Pastor, A J; Narda, G E

    2015-11-21

    A computational and experimental screening of hypothetical and real compounds exhibiting different degrees of ethylenediamine grafted to the CPO-27-Mg or Mg-DOBDC skeleton is performed in order to determine the target composition that optimizes the CO2 adsorption properties under flue gas and air filtering conditions. On the basis of the [Mg2(dobdc)] formula, eighteen hypothetical models involving 15-100% of functionalization of the coordinatively unsaturated sites (CUS) were considered by means of Grand Canonical Monte Carlo simulations to evaluate the CO2 adsorption at 298 K. In addition, post-synthesis modification was applied to CPO-27-Mg leading to three kinds of samples exhibiting 15, 50, and 60% of CUS functionalization with ethylenediamine, named CPO-27-Mg-a, CPO-27-Mg-b and CPO-27-Mg-c. Compounds were characterized using elemental analysis, TGA, FTIR spectroscopy, PXRD and DSC. Finally, bare and functionalized CPO-27-Mg materials were evaluated using gas adsorption and microcalorimetry in the 0.001-1 bar range, which is pertinent for the mentioned applications. Valuable information related to design criteria for synthesis of tuned CO2 adsorbents is derived through this computational and experimental investigation.

  3. Reconstruction of groundwater depletion using a global scale groundwater model

    Science.gov (United States)

    de Graaf, Inge; van Beek, Rens; Sutanudjaja, Edwin; Wada, Yoshi; Bierkens, Marc

    2015-04-01

    Groundwater forms an integral part of the global hydrological cycle and is the world's largest accessible source of fresh water to satisfy human water needs. It buffers variable recharge rates over time, thereby effectively sustaining river flows in times of drought as well as evaporation in areas with shallow water tables. Moreover, although lateral groundwater flows are often slow, they cross topographic and administrative boundaries at appreciable rates. Despite the importance of groundwater, most global scale hydrological models do not consider surface water-groundwater interactions or include a lateral groundwater flow component. The main reason of this omission is the lack of consistent global-scale hydrogeological information needed to arrive at a more realistic representation of the groundwater system, i.e. including information on aquifer depths and the presence of confining layers. The latter holds vital information on the accessibility and quality of the global groundwater resource. In this study we developed a high resolution (5 arc-minutes) global scale transient groundwater model comprising confined and unconfined aquifers. This model is based on MODFLOW (McDonald and Harbaugh, 1988) and coupled with the land-surface model PCR GLOBWB (van Beek et al., 2011) via recharge and surface water levels. Aquifers properties were based on newly derived estimates of aquifer depths (de Graaf et al., 2014b) and thickness of confining layers from an integration of lithological and topographical information. They were further parameterized using available global datasets on lithology (Hartmann and Moosdorf, 2011) and permeability (Gleeson et al., 2014). In a sensitivity analysis the model was run with various hydrogeological parameter settings, under natural recharge only. Scenarios of past groundwater abstractions and corresponding recharge (Wada et al., 2012, de Graaf et al. 2014a) were evaluated. The resulting estimates of groundwater depletion are lower than

  4. La Poste

    CERN Multimedia

    2004-01-01

    http://www.cern.ch/cern50/ The French Post Office has issued ten commemorative envelopes bearing original images depicting CERN and its history. This special fiftieth anniversary collector's edition will be available on the French Post Office (« La Poste ») stand at the Open Day on 16 October, in the CMS experiment hall at Cessy. Information for collectors: a pictorial postmark and date stamp have been specially designed and produced for the occasion with the assistance of CERN's graphics team. Sending a philatelic souvenir is a great way to commemorate the Open Day, so La Poste will be setting up a large post-box for that very purpose next to its stand. A perfect way to send images of CERN all around the world...

  5. A conceptual framework of groundwater flow in some crystalline aquifers in Southeastern Ghana

    Science.gov (United States)

    Yidana, Sandow Mark; Ganyaglo, Samuel; Banoeng-Yakubo, Bruce; Akabzaa, Thomas

    2011-02-01

    A conceptual groundwater flow model was developed for the crystalline aquifers in southeastern part of the Eastern region, Ghana. The objective was to determine approximate levels of groundwater recharge, estimate aquifer hydraulic parameters, and then test various scenarios of groundwater extraction under the current conditions of recharge. A steady state groundwater flow model has been calibrated against measured water levels of 19 wells in the area. The resulting recharge is estimated to range from 8.97 × 10 -5 m/d to 7.14 × 10 -4 m/d resulting in a basin wide average recharge of about 9.6% of total annual precipitation, which results in a basin wide quantitative recharge of about 2.4 million m 3/d in the area. This compares to recharge estimated from the chloride mass balance of 7.6% of precipitation determined in this study. The general groundwater flow in the area has also been determined to conform to the general northeast-southwest structural grain of the country. The implication is that the general hydrogeology is controlled by post genetic structural entities imposed on the rocks to create ingresses for sufficient groundwater storage and transport. Calibrated aquifer hydraulic conductivities range between 0.99 m/d and over 19.4 m/d. There is a significant contribution of groundwater discharge to stream flow in the study area. Increasing groundwater extraction will have an effect on stream flow. This study finds that the current groundwater extraction levels represent only 0.17% of the annual recharge from precipitation, and that groundwater can sustain future increased groundwater demands from population growth and industrialization.

  6. 地下水曝气法处理土壤及地下水中甲基叔丁基醚(MTBE)%Removal of Methyl Tert- Butyl Ether (MTBE) in Saturated Soil and Groundwater Using Air Sparging Technique

    Institute of Scientific and Technical Information of China (English)

    郑艳梅; 王战强; 黄国强; 姜斌; 李鑫钢

    2004-01-01

    通过建立 AS地下水曝气( air sparging ,AS)实验装置,研究了 MTBE的去除效果,并进行了不同曝气流量的实验研究.结果显示,用 AS法修复 MTBE 污染的饱和土壤和地下水,其去除率可以达到 95%.对不同曝气流量下的 MTBE去除效果进行比较,得到用 AS法修复 MTBE污染地下水的最佳操作条件,实验中最佳曝气流量为 0.1 m3· h-1.

  7. Groundwater Pollution and Vulnerability Assessment.

    Science.gov (United States)

    Kurwadkar, Sudarshan

    2017-10-01

    Groundwater is a critical resource that serve as a source of drinking water to large human population and, provide long-term water for irrigation purposes. In recent years; however, this precious resource being increasingly threatened, due to natural and anthropogenic activities. A variety of contaminants of emerging concern such as pharmaceuticals and personal care products, perfluorinated compounds, endocrine disruptors, and biological agents detected in the groundwater sources of both developing and developed nations. In this review paper, various studies have been included that documented instances of groundwater pollution and vulnerability to emerging contaminants of concern, pesticides, heavy metals, and leaching potential of various organic and inorganic contaminants from poorly managed residual waste products (biosolids, landfills, latrines, and septic tanks etc.). Understanding vulnerability of groundwater to pollution is critical to maintain the integrity of groundwater. A section on managed artificial recharge studies is included to highlight the sustainable approaches to groundwater conservation, replenishment and sustainability. This review paper is the synthesis of studies published in last one year that either documented the pollution problems or evaluated the vulnerability of groundwater pollution.

  8. Site scale groundwater flow in Olkiluoto

    Energy Technology Data Exchange (ETDEWEB)

    Loefman, J. [VTT Energy, Espoo (Finland)

    1999-03-01

    Groundwater flow modelling on the site scale has been an essential part of site investigation work carried out at different locations since 1986. The objective of the modelling has been to provide results that characterise the groundwater flow conditions deep in the bedrock. The main result quantities can be used for evaluation of the investigation sites and of the preconditions for safe final disposal of spent nuclear fuel. This study represents the latest modelling effort at Olkiluoto (Finland), and it comprises the transient flow analysis taking into account the effects of density variations and the repository as well as the post-glacial land uplift. The analysis is performed by means of numerical finite element simulation of coupled and transient groundwater flow and solute transport carried out up to 10000 years into the future. This work provides also the results for the site-specific data needs for the block scale groundwater flow modelling at Olkiluoto. Conceptually the fractured bedrock is divided into hydraulic units: the planar fracture zones and the remaining part of the bedrock. The equivalent-continuum (EC) model is applied so that each hydraulic unit is treated as a homogeneous and isotropic continuum with representative average characteristics. All the fracture zones are modelled explicitly and represented by two-dimensional finite elements. A site-specific simulation model for groundwater flow and solute transport is developed on the basis of the latest hydrogeological and hydrogeochemical field investigations at Olkiluoto. The present groundwater table and topography together with a mathematical model describing the land uplift at the Olkiluoto area are employed as a boundary condition at the surface of the model. The overall flow pattern is mostly controlled by the local variations in the topography. Below the island of Olkiluoto the flow direction is mostly downwards, while near the shoreline and below the sea water flows horizontally and

  9. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, ... Ozone, a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  10. Groundwater Temperature in the Limmat Valley Aquifer, Zurich

    Science.gov (United States)

    Jung, Martin; Rivera, Jaime; Blum, Philipp; Bayer, Peter

    2014-05-01

    In metropolitan areas, the thermal environment is strongly influenced by the effects of urbanization. Urban climate is often described by Urban Heat Islands (UHIs), which are also observed in the shallow subsurface. On the one hand, these temperature anomalies may put sustainable development of urban ground at a risk, but on the other hand, enhanced ground temperatures represent potential energy reservoirs. In this contribution, we focus on the role of hydrogeological conditions for the development subsurface UHIs. As a study case, the Limmat valley forming the city center of Zurich is chosen. The Limmat valley is filled with widely heterogeneous, high-conductive moraine deposits, which host groundwater reaching close to the urban surface. By rigorous temperature-depth metering of the Limmat valley aquifer since the summer of 2013, and by compiling previously measured data, the intensity of Zurich's subsurface UHI is examined. This is done with respect to its special hydrogeology, which is dominated by large-scale infiltrations from the rivers Limmat and Sihl. These generate seasonal temperature variations in the groundwater, with increasing amplitudes in the vicinity of the rivers. The seasonal groundwater temperature changes in the Limmat valley are assessed by complementing measurements from summer and winter. The measurements reveal that groundwater temperatures in Zurich are generally high. Across the Limmat valley, values of beyond 13°C are regionally observed, which is around 4 K higher than annual surface air temperature and around 3 K higher than groundwater temperature in the rural surrounding. Though, urbanization is interpreted as a secondary factor (1-1.5K), as the river infiltration naturally causes high groundwater temperatures in the Limmat valley. In the permeable gravel, the temperature-depth-profiles measured in city wells often show little fluctuation. This may be due to horizontal and vertical mixing of the groundwater, and reflects the

  11. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2012-01-01

    Groundwater is a vital resource and also a dynamic component of the water cycle. Unconfined aquifer storage is less responsive to short term weather conditions than the near surface terrestrial water storage (TWS) components (soil moisture, surface water, and snow). However, save for the permanently frozen regions, it typically exhibits a larger range of variability over multi-annual periods than the other components. Groundwater is poorly monitored at the global scale, but terrestrial water storage (TWS) change data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission are a reasonable proxy for unconfined groundwater at climatic scales.

  12. Accounting for groundwater in stream fish thermal habitat responses to climate change.

    Science.gov (United States)

    Snyder, Craig D; Hitt, Nathaniel P; Young, John A

    2015-07-01

    Forecasting climate change effects on aquatic fauna and their habitat requires an understanding of how water temperature responds to changing air temperature (i.e., thermal sensitivity). Previous efforts to forecast climate effects on brook trout (Salvelinus fontinalis) habitat have generally assumed uniform air-water temperature relationships over large areas that cannot account for groundwater inputs and other processes that operate at finer spatial scales. We developed regression models that accounted for groundwater influences on thermal sensitivity from measured air-water temperature relationships within forested watersheds in eastern North America (Shenandoah National Park, Virginia, USA, 78 sites in nine watersheds). We used these reach-scale models to forecast climate change effects on stream temperature and brook trout thermal habitat, and compared our results to previous forecasts based upon large-scale models. Observed stream temperatures were generally less sensitive to air temperature than previously assumed, and we attribute this to the moderating effect of shallow groundwater inputs. Predicted groundwater temperatures from air-water regression models corresponded well to observed groundwater temperatures elsewhere in the study area. Predictions of brook trout future habitat loss derived from our fine-grained models. were far less pessimistic than those from prior models developed at coarser spatial resolutions. However, our models also revealed spatial variation in thermal sensitivity within and among catchments resulting in a patchy distribution of thermally suitable habitat. Habitat fragmentation due to thermal barriers therefore may have an increasingly important role for trout population viability in headwater streams. Our results demonstrate that simple adjustments to air-water temperature regression models can provide a powerful and cost-effective approach for predicting future stream temperatures while accounting for effects of groundwater.

  13. Model-based assessment of the potential of seasonal aquifer thermal energy storage and recovery as a groundwater ecosystem service for the Brussels-Capital Region

    Science.gov (United States)

    Anibas, Christian; Huysmans, Marijke

    2015-04-01

    Urban areas are characterized by their concentrated demand of energy, applying a high pressure on urban ecosystems including atmosphere, soils and groundwater. In the light of global warming, urbanization and an evolving energy system, it is important to know how urbanized areas can contribute to their own energy demands. One option is to use the possibilities aquifers offer as an ecosystem service (BONTE et al., 2011). If used effectively an improvement in air and groundwater quality is achieved. Additionally, the more efficient distribution of the used energy may also lead to a decrease in primary energy consumption (ZUURBIER, 2013). Therefore, investigations of the potential of seasonal aquifer thermal energy storage and recovery (ATES) for the Brussels-Capital Region, Belgium is being conducted. The potential of ATES systems are of special interest for energy demands in high density urban areas because of such infrastructure as office buildings, schools, hospitals and shopping malls. In an open water circuit ATES systems consist of two or more groundwater wells, where in seasonal cycles one subtracts and the other recharges water to the aquifer. Heat pumps use the heat capacity of water for heating or cooling a building. An important limitation of the methodology is the quality of the groundwater used (i.e. precipitation of Fe- or Mn-oxides can decrease the yield). However, ATES systems on the other hand can also improve groundwater quality and groundwater ecosystems. The current knowledge of the potential for ATES systems in the Brussels-Capital Region is based on geological assessments from VITO (2007). The Brussels-Capital Region is divided into a western and eastern section with respect to geology. While the western part has less favorable conditions for ATES, the eastern is composed of the Brussels Sand formation, which is a 20-40 m thick aquifer layer that has the highest potential for ATES systems in the region. By applying groundwater flow and heat

  14. Application of first order kinetics to characterize MTBE natural attenuation in groundwater.

    Science.gov (United States)

    Metcalf, Meredith J; Stevens, Graham J; Robbins, Gary A

    2016-04-01

    Methyl tertiary butyl ether (MTBE) was a gasoline oxygenate that became widely used in reformulated gasoline as a means to reduce air pollution in the 1990s. Unfortunately, many of the underground storage tanks containing reformulated gasoline experienced subsurface releases which soon became a health concern given the increase in public and private water supplies containing MTBE. Many states responded to this by banning the use of MTBE as an additive, including Connecticut. Although MTBE dissipates by natural attenuation, it continues to be prevalent in groundwater long after the Connecticut ban in 2004. This study estimated the rate of the natural attenuation in groundwater following the Connecticut ban by evaluating the MTBE concentration two years prior to and two years after the MTBE ban at eighty-three monitoring wells from twenty-two retail gasoline stations where MTBE contamination was observed. Sites chosen for this study had not undergone active remediation ensuring no artificial influence to the natural attenuation processes that controls the migration and dissipation of MTBE. Results indicate that MTBE has dissipated in the natural environment, at more than 80% of the sites and at approximately 82% of the individual monitoring wells. In general, dissipation approximated first order kinetics. Dissipation half-lives, calculated using concentration data from the two year period after the ban, ranged from approximately three weeks to just over seven years with an average half-life of 7.3 months with little variability in estimates for different site characteristics. The accuracy of first order estimates to predict further MTBE dissipation were tested by comparing predicted concentrations with those observed after the two year post-ban period; the predicted concentrations closely match the observed concentrations which supports the use of first order kinetics for predictions of this nature.

  15. GROUNDWATER HYDROCHEMISTRY EVALUATION IN RURAL ...

    African Journals Online (AJOL)

    Osondu

    2012-10-09

    Oct 9, 2012 ... the quality of groundwater from domestic water supply boreholes across rural Botswana. Ionic ... quality limits the supply of potable fresh water. To utilize and protect valuable water ..... prescribed specification of World Health.

  16. Groundwater Vulnerability Regions of Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The regions onThis map represent areas with similar hydrogeologic characteristics thought to represent similar potentials for contamination of groundwater and/or...

  17. Vulnerability Assessment of Groundwater Resources by Nutrient Source Apportionment to Individual Groundwater Wells: A Case Study in North Carolina

    Science.gov (United States)

    Ayub, R.; Obenour, D. R.; Keyworth, A. J.; Genereux, D. P.; Mahinthakumar, K.

    2016-12-01

    Groundwater contamination by nutrients (nitrogen and phosphorus) is a major concern in water table aquifers that underlie agricultural areas in the mid-Atlantic Coastal Plain of the United States. High nutrient concentrations leaching into shallow groundwater can lead to human health problems and eutrophication of receiving surface waters. Liquid manure from concentrated animal feeding operations (CAFOs) stored in open-air lagoons and applied to spray fields can be a significant source of nutrients to groundwater, along with septic waste. In this study, we developed a model-based methodology for source apportionment and vulnerability assessment using sparse groundwater quality sampling measurements for Duplin County, North Carolina (NC), obtained by the NC Department of Environmental Quality (NC DEQ). This model provides information relevant to management by estimating the nutrient transport through the aquifer from different sources and addressing the uncertainty of nutrient contaminant propagation. First, the zones of influence (dependent on nutrient pathways) for individual groundwater monitoring wells were identified using a two-dimensional vertically averaged groundwater flow and transport model incorporating geologic uncertainty for the surficial aquifer system. A multiple linear regression approach is then applied to estimate the contribution weights for different nutrient source types using the nutrient measurements from monitoring wells and the potential sources within each zone of influence. Using the source contribution weights and their uncertainty, a probabilistic vulnerability assessment of the study area due to nutrient contamination is performed. Knowledge of the contribution of different nutrient sources to contamination at receptor locations (e.g., private wells, municipal wells, stream beds etc.) will be helpful in planning and implementation of appropriate mitigation measures.

  18. Analysis on oral health status of 55 military persons in an air force command post of Xi'an%西安空军某指挥所55名官兵的口腔健康状况

    Institute of Scientific and Technical Information of China (English)

    王军; 吕波涛; 艾玉; 齐志远; 安源; 郭静; 李刚; 李广文; 赵增强; 张燕; 李卉; 王娟; 王宇欣; 李翠霞; 王东平

    2012-01-01

    目的 了解解放军人员中的口腔健康状况,为军队开展军人口腔疾病医疗保健提供依据.方法 采用世界卫生组织1987年版口腔健康调查基本方法和标准器材,并根据我军实际情况需要设定了军人口腔健康调查项目,对西安空军某指挥所官兵进行口腔健康调查.获得数据利用FoxPr0 6.0软件建立数据库,SPSS 11.5软件进行统计分析.结果 共调查55人,结果表明该所现役人员龋均为0.75 ±1.03,患龋率为21.8%.牙结石发生率为78.2%,牙周病发病率为1.8%.结论 该部官兵龋病患病率比较平稳,龋病大部分处于早期阶段.牙结石发生率较大,需要开展大量的口腔洁牙治疗.而牙周病比较平稳,大多数为早期牙周病,通过洁牙可以有效预防和治疗.口腔健康保健、定期口腔检查和早期口腔疾病治疗对预防官兵口腔疾病极其重要.%[Objective]To survey the oral health status of PLA military personnel, provide a basis for carrying out the prevention and treatment of oral diseases in military persons. [ Methods] Based on the WHO methodology of oral health survey (1987), the i-teras of oral health survey of military persons were designed according to the actual situation of PLA, and military persons in an air force command post of Xi'an were collected for oral health survey. The data were analyzed with FoxPro 6. 0 and SPSS 11. 5. [Results] A total of 55 military persons were investigated. The average caries was0.75 ?1.03, caries prevalence was 21.8% , the incidence rate of dental calculus was 78. 2% , and the incidence rate of periodontal diseases was 1.8%. [ Conchuioil] The caries prevalence of military persons in an air force command post is stable, and caries in most military persons are in the early stage. The incidence rate of dental calculus is high, which indicates that the dental cleaning is necessary. The incidence rate of periodontal diseases is stable, most are in the early stage, and can be

  19. Optimal and Sustainable Groundwater Extraction

    Directory of Open Access Journals (Sweden)

    Christopher A. Wada

    2010-08-01

    Full Text Available With climate change exacerbating over-exploitation, groundwater scarcity looms as an increasingly critical issue worldwide. Minimizing the adverse effects of scarcity requires optimal as well as sustainable patterns of groundwater management. We review the many sustainable paths for groundwater extraction from a coastal aquifer and show how to find the particular sustainable path that is welfare maximizing. In some cases the optimal path converges to the maximum sustainable yield. For sufficiently convex extraction costs, the extraction path converges to an internal steady state above the level of maximum sustainable yield. We describe the challenges facing groundwater managers faced with multiple aquifers, the prospect of using recycled water, and the interdependence with watershed management. The integrated water management thus described results in less water scarcity and higher total welfare gains from groundwater use. The framework also can be applied to climate-change specifications about the frequency, duration, and intensity of precipitation by comparing before and after optimal management. For the case of South Oahu in Hawaii, the prospect of climate change increases the gains of integrated groundwater management.

  20. Computation of groundwater resources and recharge in Chithar River Basin, South India.

    Science.gov (United States)

    Subramani, T; Babu, Savithri; Elango, L

    2013-01-01

    Groundwater recharge and available groundwater resources in Chithar River basin, Tamil Nadu, India spread over an area of 1,722 km(2) have been estimated by considering various hydrological, geological, and hydrogeological parameters, such as rainfall infiltration, drainage, geomorphic units, land use, rock types, depth of weathered and fractured zones, nature of soil, water level fluctuation, saturated thickness of aquifer, and groundwater abstraction. The digital ground elevation models indicate that the regional slope of the basin is towards east. The Proterozoic (Post-Archaean) basement of the study area consists of quartzite, calc-granulite, crystalline limestone, charnockite, and biotite gneiss with or without garnet. Three major soil types were identified namely, black cotton, deep red, and red sandy soils. The rainfall intensity gradually decreases from west to east. Groundwater occurs under water table conditions in the weathered zone and fluctuates between 0 and 25 m. The water table gains maximum during January after northeast monsoon and attains low during October. Groundwater abstraction for domestic/stock and irrigational needs in Chithar River basin has been estimated as 148.84 MCM (million m(3)). Groundwater recharge due to monsoon rainfall infiltration has been estimated as 170.05 MCM based on the water level rise during monsoon period. It is also estimated as 173.9 MCM using rainfall infiltration factor. An amount of 53.8 MCM of water is contributed to groundwater from surface water bodies. Recharge of groundwater due to return flow from irrigation has been computed as 147.6 MCM. The static groundwater reserve in Chithar River basin is estimated as 466.66 MCM and the dynamic reserve is about 187.7 MCM. In the present scenario, the aquifer is under safe condition for extraction of groundwater for domestic and irrigation purposes. If the existing water bodies are maintained properly, the extraction rate can be increased in future about 10% to 15%.

  1. Approaches to Post-disaster Environmental Recovery

    Directory of Open Access Journals (Sweden)

    Mehrdad Farrokhi

    2016-01-01

    Full Text Available Background: Environment and its ecosystems are affected by various natural and man-made disasters. The environmental management in disasters tries to protect ecosystems, sustain development, reduce disaster risk, and adapt to or decrease the impact of climate change. This study aimed to investigate the impact of disasters on the environment and methods of reducing these effects. Materials and Methods: This review study was conducted by searching PubMed, Google Scholar, Elsevier, UNEP, SID, and Magiran databases using keywords of “environment”, “disasters”, “recovery”, and “lessons learned” from 1999 to 2015. Results: Decrease in surface and groundwater resources, pollution of water resources, deforestation, desertification, soil erosion, air pollution and extinction of animal species are among post-disaster environmental damages. As a result of such changes in the environment and ecosystem, water shortage and drought, loss of vegetation, and food insecurity will ensue. Due to these destructive incidents, the people’s ability to provide necessary resources for living decreases and their very lives are threatened. Consequently, they are forced to immigrate to save their lives. Conclusion: Environmental recovery is one of the effective strategies for achieving sustainable development. In this regard, public and private organizations as well as international ones and people should work together. Responsible organizations, the stakeholders at different levels, and the public must be trained in this area and introduced to the latest international standards. Rules and policies should be reviewed and revised in accordance with today’s needs and international standards.

  2. Modeling mineral phase change chemistry of groundwater in a rural-urban fringe.

    Science.gov (United States)

    Singh, S K; Srivastava, Prashant K; Gupta, M; Mukherjee, S

    2012-01-01

    This research paper aims to determine the genetic origin of the chemical elements in groundwater. It deals with the results of physicochemical parameters, to evaluate the hydro-geochemistry of groundwater in rural-urban fringe of district Bareilly, India. Pre- and post-monsoon sampling has been carried out, which reveals inter-seasonal variability effect on the hydro-geochemical processes. Geochemical modeling especially computation of saturation index was undertaken using the WATEQ4F model. Majority of samples fall in the category of undersaturation, which further suggests that groundwater still has potential to dissolve more minerals. Chemical categorizations of groundwater samples were performed with the help of the Aquachem model. Grouping of groundwater on the Piper diagram reveals a common composition and origin. In most of the area, water facies is of Ca(2+)-HCO(3)(-) type in both the seasons. It also indicates that in pre-monsoon, ion exchange is the dominant process, whereas in post-monsoon, both ion exchanges as well as reverse ion exchanges are reported in the groundwater of the study area.

  3. Hydrologic and nutrient response of groundwater to flooding of cranberry farms in southeastern Massachusetts, USA

    Science.gov (United States)

    Kennedy, Casey D.

    2015-06-01

    ), decreases in NO3- concentration from 565 μM (pre-flood) to 99 μM (post-flood) were consistent with winter floodwater as a source of low-NO3- groundwater recharge.

  4. Influences of groundwater extraction on the distribution of dissolved As in shallow aquifers of West Bengal, India.

    Science.gov (United States)

    Neidhardt, Harald; Berner, Zsolt; Freikowski, Dominik; Biswas, Ashis; Winter, Josef; Chatterjee, Debashis; Norra, Stefan

    2013-11-15

    Here we report temporal changes of As concentrations in shallow groundwater of the Bengal Delta Plain (BDP). Observed fluctuations are primarily induced by seasonally occurring groundwater movement, but can also be connected to anthropogenic groundwater extraction. Between December 2009 and July 2010, pronounced variations in the groundwater hydrochemistry were recorded in groundwater samples of a shallow monitoring well tapping the aquifer in 22-25 m depth, where Astot concentrations increased within weeks from 100 to 315 μg L(-1). These trends are attributed to a vertically shift of the hydrochemically stratified water column at the beginning of the monsoon season. This naturally occurring effect can be additionally superimposed by groundwater extraction, as demonstrated on a local scale by an in situ experiment simulating extensive groundwater withdrawal during the dry post-monsoon season. Results of this experiment suggest that groundwater extraction promoted an enduring change within the distribution of dissolved As in the local aquifer. Presented outcomes contribute to the discussion of anthropogenic pumping influences that endanger the limited and yet arsenic-free groundwater resources of the BDP.

  5. Evaluation of groundwater quality and suitability for irrigation and drinking purposes in southwest Punjab, India using hydrochemical approach

    Science.gov (United States)

    Sharma, Diana Anoubam; Rishi, Madhuri S.; Keesari, Tirumalesh

    2016-08-01

    Groundwater samples from alluvial aquifers of Bathinda district, southwest Punjab were measured for physicochemical parameters as well as major ion chemistry to evaluate the groundwater suitability for drinking and irrigation purposes and to present the current hydrochemical status of groundwater of this district. Temporal variations were analyzed by comparing the pre- and post-monsoon groundwater chemistry. Most of the samples showed contamination: F- (72 %), Mg2+ (22 %), SO4 2- (28 %), TH (25 %), NO3 - (22 %), HCO3 - (22 %) and TDS (11 %) during pre-monsoon and F- (50 %), Mg2+ (39 %), SO4 2- (22 %), TH (28 %), NO3 - (22 %) and TDS (28 %) during post-monsoon above permissible limits for drinking, while rest of the parameters fall within the limits. Irrigation suitability was checked using sodium absorption ratio (SAR), residual sodium carbonate (RSC), percent sodium (Na%) and permeability index (PI). Most of the samples fall under good to suitable category during pre-monsoon period, but fall under doubtful to unsuitable category during post-monsoon period. Presence of high salt content in groundwater during post-monsoon season reflects leaching of salts present in the unsaturated zone by infiltrating precipitation. Hydrochemical data was interpreted using Piper's trilinear plot and Chadha's plot to understand the various geochemical processes affecting the groundwater quality. The results indicate that the order of cation dominance is Na+ > Mg2+ > Ca2+, while anion dominance is in the order Cl- > HCO3 - > SO4 2-. The geochemistry of groundwater of this district is mainly controlled by the carbonate and silicate mineral dissolution and ion exchange during pre-monsoon and leaching from the salts deposited in vadose zone during post-monsoon. The main sources of contamination are soluble fertilizers and livestock wastes. This study is significant as the surface water resources are limited and the quality and quantity of groundwater are deteriorating with time due to

  6. Monitoring post

    DEFF Research Database (Denmark)

    Hansen, Pelle Guldborg; Jespersen, Andreas Maaløe

    2013-01-01

    This blog reports on the rumour that White House considers establishing a nudge unit similar to the UK Behavioural Insights Team. Given The Nudging Networks purpose and the work of the iNudgeYou-team this post is updated continuously to follow the US debate as it unfolds. Which issues are raised......? How is the debate different from the one in the UK? And how does our work relate to the issues raised? The post has already been referenced in several US media, including US News....

  7. Groundwater surface water interactions and the role of phreatophytes in identifying recharge zones

    Directory of Open Access Journals (Sweden)

    T. S. Ahring

    2012-11-01

    Full Text Available Groundwater and surface water interactions within riparian corridors impact the distribution of phreatophytes that tap into groundwater stores. The changes in canopy area of phreatophytes over time is related to changes in depth to groundwater, distance from a stream or river, and hydrologic soil group. Remote sensing was used to determine the location of trees with pre-development and post-development aerial photography over the Ogallala Aquifer in the central plains of the United States. It was found that once the depth to groundwater becomes greater than about 3 m, tree populations decrease as depth to water increases. This subsequently limited the extent of phreatophytes to within 700 m of the river. It was also found that phreatophytes have a higher likelihood of growing on hydrologic soil groups with higher saturated hydraulic conductivity. Phreatophytes exist along portions of the Arkansas River corridor where significant decreases in groundwater occurred as long as alluvium exists to create perched conditions where trees survive dry periods. Significant decreases (more that 50% in canopy cover exists along river segments where groundwater declined by more than 10 m, indicating areas with good hydraulic connectivity between surface water and groundwater. Thus, interpretation of changes in phreatophyte distribution using historical and recent aerial photography is important in delineating zones of enhanced recharge where aquifers might be effectively recharged through diversion of surface water runoff.

  8. Groundwater surface water interactions through streambeds and the role of phreatophytes in identifying important recharge zones

    Directory of Open Access Journals (Sweden)

    T. S. Ahring

    2012-06-01

    Full Text Available Groundwater and surface water interactions within riparian corridors impact the distribution of phreatophytes that tap into groundwater stores. The changes in canopy area of phreatophytes over time is related to changes in depth to groundwater, distance from a stream or river, and hydrologic soil group. Remote sensing was used to determine the location of trees with predevelopment and post-development aerial photography over the Ogallala Aquifer in the central plains of the United States. It was found that once the depth to groundwater becomes greater than about 3 m, tree populations decrease as depth to water increases. This subsequently limited the extent of phreatophytes to within 700 m of the river. It was also found that phreatophytes have a higher likelihood of growing on hydrologic soil groups with higher saturated hydraulic conductivity. Phreatophytes exist along portions of the Arkansas River corridor where significant decreases in groundwater occurred as long as alluvium exists to create perched conditions where trees survive dry periods. Significant decreases (more that 50% in canopy cover exists along river segments where groundwater declined by more than 10 m, indicating areas with good hydraulic connectivity between surface water and groundwater. Thus, interpretation of changes in phreatophyte distribution using historical and recent aerial photophaphy is important in delineating zones of enhanced recharge where aquifers might be effectively recharged through diversion of surface water runoff.

  9. Hydrogeochemistry and groundwater quality assessment of Ranipet industrial area, Tamil Nadu, India

    Indian Academy of Sciences (India)

    G Tamma Rao; V V S Gurunadha Rao; K Ranganathan

    2013-06-01

    One of the highly polluted areas in India located at Ranipet occupies around 200 tanneries and other small scale chemical industries. Partially treated industrial effluents combined with sewage and other wastes discharged on the surface cause severe groundwater pollution in the industrial belt. This poses a problem of supply of safe drinking water in the rural parts of the country. A study was carried out to assess the groundwater pollution and identify major variables affecting the groundwater quality in Ranipet industrial area. Twenty five wells were monitored during pre- and post-monsoon in 2008 and analyzed for the major physico-chemical variables. The water quality variables such as total dissolved solids (TDS), Iron (Fe2+), Hexavalent Chromium (Cr6+), at most of the sampling locations exceeded the ISI and WHO guideline levels for drinking water. Multivariate statistical techniques such as factor analysis were applied to identify the major factors (variables) corresponding to the different source of variation in groundwater quality. The water quality of groundwater is influenced by both anthropogenic and chemical weathering. The most serious pollution threat to groundwater is from TDS, Cr6+ and Fe2+, which are associated with sewage and pollution of tannery waste. The study reveals that the groundwater quality changed due to anthropogenic and natural influences such as agricultural, natural weathering process.

  10. Hydrogeochemistry and groundwater quality assessment of Ranipet industrial area, Tamil Nadu, India

    Science.gov (United States)

    Rao, G. Tamma; Rao, V. V. S. Gurunadha; Ranganathan, K.

    2013-06-01

    One of the highly polluted areas in India located at Ranipet occupies around 200 tanneries and other small scale chemical industries. Partially treated industrial effluents combined with sewage and other wastes discharged on the surface cause severe groundwater pollution in the industrial belt. This poses a problem of supply of safe drinking water in the rural parts of the country. A study was carried out to assess the groundwater pollution and identify major variables affecting the groundwater quality in Ranipet industrial area. Twenty five wells were monitored during pre- and post-monsoon in 2008 and analyzed for the major physico-chemical variables. The water quality variables such as total dissolved solids (TDS), Iron (Fe2 + ), Hexavalent Chromium (Cr6 + ), at most of the sampling locations exceeded the ISI and WHO guideline levels for drinking water. Multivariate statistical techniques such as factor analysis were applied to identify the major factors (variables) corresponding to the different source of variation in groundwater quality. The water quality of groundwater is influenced by both anthropogenic and chemical weathering. The most serious pollution threat to groundwater is from TDS, Cr6 + and Fe2 + , which are associated with sewage and pollution of tannery waste. The study reveals that the groundwater quality changed due to anthropogenic and natural influences such as agricultural, natural weathering process.

  11. SR-Site - sulphide content in the groundwater at Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Tullborg, E-L (Terralogica (Sweden)); Smellie, J (Conterra (Sweden)); Nilsson, A-Ch (Geosigma (Sweden)); Gimeno, M J; Auque, LF (Univ. of Zaragoza (Spain)); Bruchert, V (Stockholms Universitet (Sweden)); Molinero, J (Amphos21 (Spain))

    2010-12-15

    Sulphide concentrations in groundwater play a key role in the long-term reliability of the metal canisters containing the radioactive waste within a disposal facility for nuclear waste. This is because sulphide in the groundwaters circulating in the vicinity of the deposition tunnels can react with copper in the canisters causing corrosion and therefore reducing their expected lifetime; in a worst case scenario erosion of the bentonite buffer material will expose the canister more rapidly to the fracture groundwater.Sulphide in the groundwater is predominantly microbially produced and thereby controlled by the content of oxidised sulphur sources, organics (carbon sources), reductants (mainly Fe(II), DOC, H{sub 2} and CH{sub 4}), and also flow and mixing of different groundwater types. In addition, achieved saturation in respect to amorphous Fe-monosulphide will control the possible maximum values and will also limit the Fe2+ and S2- values in the groundwater. The aim of this report is to assess realistic, representative and reliable sulphide groundwater concentrations at present conditions in Forsmark and also to evaluate possible changes during different climatic conditions covering the repository operation period (some tens to hundreds of years), post closure conditions (some thousand of years) and the proceeding temperate period (some tens of thousands of years) which may be extended due to enhanced greenhouse effects etc. It is expected that this period will be followed by the onset of the next glaciation during which periglacial (permafrost), glacial and postglacial conditions may succeed each other. To achieve these aims, an evaluation is performed of all the sulphide-related data reported from the Forsmark site investigations /Laaksoharju et al. 2008/ and later monitoring campaigns, all of which are stored in the Sicada database. This evaluation shows that values from the Complete Chemical Characterisation (CCC) sampling are usually lower than those measured

  12. Hydrogeochemistry and Water Quality Index in the Assessment of Groundwater Quality for Drinking Uses.

    Science.gov (United States)

    Batabyal, Asit Kumar; Chakraborty, Surajit

    2015-07-01

    The present investigation is aimed at understanding the hydrogeochemical parameters and development of a water quality index (WQI) to assess groundwater quality of a rural tract in the northwest of Bardhaman district of West Bengal, India. Groundwater occurs at shallow depths with the maximum flow moving southeast during pre-monsoon season and south in post-monsoon period. The physicochemical analysis of groundwater samples shows the major ions in the order of HCO3>Ca>Na>Mg>Cl>SO4 and HCO3>Ca>Mg>Na>Cl>SO4 in pre- and post-monsoon periods, respectively. The groundwater quality is safe for drinking, barring the elevated iron content in certain areas. Based on WQI values, groundwater falls into one of three categories: excellent water, good water, and poor water. The high value of WQI is because of elevated concentration of iron and chloride. The majority of the area is occupied by good water in pre-monsoon and poor water in post-monsoon period.

  13. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2011-01-01

    Most people think of groundwater as a resource, but it is also a useful indicator of climate variability and human impacts on the environment. Groundwater storage varies slowly relative to other non-frozen components of the water cycle, encapsulating long period variations and trends in surface meteorology. On seasonal to interannual timescales, groundwater is as dynamic as soil moisture, and it has been shown that groundwater storage changes have contributed to sea level variations. Groundwater monitoring well measurements are too sporadic and poorly assembled outside of the United States and a few other nations to permit direct global assessment of groundwater variability. However, observational estimates of terrestrial water storage (TWS) variations from the GRACE satellites largely represent groundwater storage variations on an interannual basis, save for high latitude/altitude (dominated by snow and ice) and wet tropical (surface water) regions. A figure maps changes in mean annual TWS from 2009 to 2010, based on GRACE, reflecting hydroclimatic conditions in 2010. Severe droughts impacted Russia and the Amazon, and drier than normal weather also affected the Indochinese peninsula, parts of central and southern Africa, and western Australia. Groundwater depletion continued in northern India, while heavy rains in California helped to replenish aquifers that have been depleted by drought and withdrawals for irrigation, though they are still below normal levels. Droughts in northern Argentina and western China similarly abated. Wet weather raised aquifer levels broadly across western Europe. Rains in eastern Australia caused flooding to the north and helped to mitigate a decade long drought in the south. Significant reductions in TWS seen in the coast of Alaska and the Patagonian Andes represent ongoing glacier melt, not groundwater depletion. Figures plot time series of zonal mean and global GRACE derived non-seasonal TWS anomalies (deviation from the mean of

  14. Groundwater recharge and agricultural contamination

    Science.gov (United States)

    Böhlke, J.K.

    2002-01-01

    Agriculture has had direct and indirect effects on the rates and compositions of groundwater recharge and aquifer biogeochemistry. Direct effects include dissolution and transport of excess quantities of fertilizers and associated materials and hydrologic alterations related to irrigation and drainage. Some indirect effects include changes in water-rock reactions in soils and aquifers caused by increased concentrations of dissolved oxidants, protons, and major ions. Agrilcultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO3-, N2, Cl, SO42-, H+, P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well a wide variety of pesticides and other organic compounds. For reactive contaminants like NO3-, a combination of chemical, isotopic, and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. Groundwater records derived from multi-component hydrostratigraphic data can be used to quantify recharge rates and residence times of water and dissolved contaminants, document past variations in recharging contaminant loads, and identify natural contaminant-remediation processes. These data indicate that many of the world's surficial aquifers contain transient records of changing agricultural contamination from the last half of the 20th century. The transient agricultural groundwater signal has important implications for long-term trends and spatial heterogeneity in discharge.

  15. GEO STATISTICAL MODELLING FOR GROUNDWATER POLLUTION IN SALEM, TAMILNADU- A GIS BASED APPROACH

    Directory of Open Access Journals (Sweden)

    S. Prabaharan,

    2011-02-01

    Full Text Available Water is one of the essential natural resources for the existence and development of life on the earth. The demand for water has increased over the years, and has led to a water scarcity. Ground waters are themajor resources to meet out the entire requirements. Pollution of air, water and land has an effect on the quality of the ground waters. The chemical characteristics of groundwater in Salem taluk of Salem district have been studied using Geostatistical modeling to evaluate the suitability of water for irrigation and domestic uses. The 32 water samples from PWD wells taken during the years 1999 to 2009 for post monsson and pre monsoon were tested for various chemical parameters like pH and TDS .The Geostatistical analyst of ArcGIS was used to generate voronoi maps like mean, mode, standard deviation, cluster & simple to study the spatial pattern of contamination movement for the years 1999 to 2009. Trend analysis was performed to identify trends in the input dataset. The concentrations of physical and chemical constituents in the water samples were compared with the World Health Organization (WHO standard to know the suitability of water for drinking.

  16. Groundwater resource-directed measures software

    African Journals Online (AJOL)

    2006-07-21

    Jul 21, 2006 ... 1Institute for Groundwater Studies, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa ... In this paper the methods developed for the GRDM .... The geothermal gradient for groundwater, that is, the.

  17. ASSESSMENT OF GROUNDWATER QUALITY IN SHALLOW ...

    African Journals Online (AJOL)

    development of human societies. In Okrika Island ... abstraction of groundwater due to population increase in Port ... 298. Nwankwoala and Walter: Assessment of Groundwater Quality in Shallow Coastal Aquifers ..... and Tai-Eleme areas.

  18. Future research needs involving pathogens in groundwater

    Science.gov (United States)

    Contamination of groundwater by enteric pathogens has commonly been associated with disease outbreaks. Proper management and treatment of pathogen sources are important barriers to preventing groundwater contamination. However, non-point sources of pathogen contamination are frequently difficult to ...

  19. Valuing groundwater: A practical approach for integrating ...

    African Journals Online (AJOL)

    groundwater economic values into decision making ... The methodology incorporates a 2-tiered valuation approach. .... groundwater systems in Botswana (SADC, 2010). .... tion) can be investigated to support water resource management.

  20. Seasonal Variation in Groundwater Quality of Yavatmal District, India

    Directory of Open Access Journals (Sweden)

    P. N. Rajankar

    2011-01-01

    Full Text Available Seventy samples of groundwater were collected from different parts of Yavatmal District, India and analyzed. The results of this analysis were compared with the WHO water quality standards. The groundwater quality in this district showed slightly seasonal variation while the data computed in Water Quality Index (WQI calculator. The WQI was varied from 73.0 to 80.2 during pre monsoon and 68.7 to 72.4 in post monsoon season, which showed slightly seasonal variation. This may be attributed to surface runoff and percolation process. The results showed that, the water in these areas are bacteriologically not safe and need treatment before it is used for drinking.

  1. Heavy metal contamination and its indexing approach for groundwater of Goa mining region, India

    Science.gov (United States)

    Singh, Gurdeep; Kamal, Rakesh Kant

    2017-06-01

    The objective of the study is to reveal the seasonal variations in the groundwater quality with respect to heavy metal contamination. To get the extent of the heavy metals contamination, groundwater samples were collected from 45 different locations in and around Goa mining area during the monsoon and post-monsoon seasons. The concentration of heavy metals, such as lead, copper, manganese, zinc, cadmium, iron, and chromium, were determined using atomic absorption spectrophotometer. Most of the samples were found within limit except for Fe content during the monsoon season at two sampling locations which is above desirable limit, i.e., 300 µg/L as per Indian drinking water standard. The data generated were used to calculate the heavy metal pollution index (HPI) for groundwater. The mean values of HPI were 1.5 in the monsoon season and 2.1 in the post-monsoon season, and these values are well below the critical index limit of 100.

  2. Heavy metal contamination and its indexing approach for groundwater of Goa mining region, India

    Science.gov (United States)

    Singh, Gurdeep; Kamal, Rakesh Kant

    2016-06-01

    The objective of the study is to reveal the seasonal variations in the groundwater quality with respect to heavy metal contamination. To get the extent of the heavy metals contamination, groundwater samples were collected from 45 different locations in and around Goa mining area during the monsoon and post-monsoon seasons. The concentration of heavy metals, such as lead, copper, manganese, zinc, cadmium, iron, and chromium, were determined using atomic absorption spectrophotometer. Most of the samples were found within limit except for Fe content during the monsoon season at two sampling locations which is above desirable limit, i.e., 300 µg/L as per Indian drinking water standard. The data generated were used to calculate the heavy metal pollution index (HPI) for groundwater. The mean values of HPI were 1.5 in the monsoon season and 2.1 in the post-monsoon season, and these values are well below the critical index limit of 100.

  3. INTEC Groundwater Monitoring Report 2006

    Energy Technology Data Exchange (ETDEWEB)

    J. R. Forbes

    2007-02-01

    This report summarizes 2006 perched water and groundwater monitoring activities at the Idaho Nuclear Technology and Engineering Center (INTEC) located at the Idaho National Laboratory (INL). During 2006, groundwater samples were collected from a total of 22 Snake River Plain Aquifer (SRPA) monitoring wells, plus six aquifer wells sampled for the Idaho CERCLA Disposal Facility (ICDF) monitoring program. In addition, perched water samples were collected from 21 perched wells and 19 suction lysimeters. Groundwater and perched water samples were analyzed for a suite of radionuclides and inorganic constituents. Laboratory results in this report are compared to drinking water maximum contaminant levels (MCLs). Such comparison is for reference only and it should be noted that the Operable Unit 3-13 Record of Decision does not require that perched water comply with drinking water standards.

  4. Groundwater arsenic contamination throughout China.

    Science.gov (United States)

    Rodríguez-Lado, Luis; Sun, Guifan; Berg, Michael; Zhang, Qiang; Xue, Hanbin; Zheng, Quanmei; Johnson, C Annette

    2013-08-23

    Arsenic-contaminated groundwater used for drinking in China is a health threat that was first recognized in the 1960s. However, because of the sheer size of the country, millions of groundwater wells remain to be tested in order to determine the magnitude of the problem. We developed a statistical risk model that classifies safe and unsafe areas with respect to geogenic arsenic contamination in China, using the threshold of 10 micrograms per liter, the World Health Organization guideline and current Chinese standard for drinking water. We estimate that 19.6 million people are at risk of being affected by the consumption of arsenic-contaminated groundwater. Although the results must be confirmed with additional field measurements, our risk model identifies numerous arsenic-affected areas and highlights the potential magnitude of this health threat in China.

  5. Quantifying Volume of Groundwater in High Elevation Meadows

    Science.gov (United States)

    Ciruzzi, D.; Lowry, C.

    2013-12-01

    Assessing the current and future water needs of high elevation meadows is dependent on quantifying the volume of groundwater stored within the meadow sediment. As groundwater dependent ecosystems, these meadows rely on their ability to capture and store water in order to support ecologic function and base flow to streams. Previous research of these meadows simplified storage by assuming a homogenous reservoir of constant thickness. These previous storage models were able to close the water mass balance, but it is unclear if these assumptions will be successful under future anthropogenic impacts, such as increased air temperature resulting in dryer and longer growing seasons. Applying a geophysical approach, ground-penetrating radar was used at Tuolumne Meadows, CA to qualitatively and quantitatively identify the controls on volume of groundwater storage. From the geophysical results, a three-dimensional model of Tuolumne Meadows was created, which identified meadow thickness and bedrock geometry. This physical model was used in a suite of numerical models simulating high elevation meadows in order to quantify volume of groundwater stored with temporal and spatial variability. Modeling efforts tested both wet and dry water years in order to quantify the variability in the volume of groundwater storage for a range of aquifer properties. Each model was evaluated based on the seasonal depth to water in order to evaluate a particular scenario's ability to support ecological function and base flow. Depending on the simulated meadows ability or inability to support its ecosystem, each representative meadow was categorized as successful or unsuccessful. Restoration techniques to increase active storage volume were suggested at unsuccessful meadows.

  6. Food supply reliance on groundwater

    Science.gov (United States)

    Dalin, Carole; Puma, Michael; Wada, Yoshihide; Kastner, Thomas

    2016-04-01

    Water resources, essential to sustain human life, livelihoods and ecosystems, are under increasing pressure from population growth, socio-economic development and global climate change. As the largest freshwater resource on Earth, groundwater is key for human development and food security. Yet, excessive abstraction of groundwater for irrigation, driven by an increasing demand for food in recent decades, is leading to fast exhaustion of groundwater reserves in major agricultural areas of the world. Some of the highest depletion rates are observed in Pakistan, India, California Central Valley and the North China Plain aquifers. In addition, the growing economy and population of several countries, such as India and China, makes prospects of future available water and food worrisome. In this context, it is becoming particularly challenging to sustainably feed the world population, without exhausting our water resources. Besides, food production and consumption across the globe have become increasingly interconnected, with many areas' agricultural production destined to remote consumers. In this globalisation era, trade is crucial to the world's food system. As a transfer of water-intensive goods, across regions with varying levels of water productivity, food trade can save significant volumes of water resources globally. This situation makes it essential to address the issue of groundwater overuse for global food supply, accounting for international food trade. To do so, we quantify the current, global use of non-renewable groundwater for major crops, accounting for various water productivity and trade flows. This will highlight areas requiring quickest attention, exposing major exporters and importers of non-renewable groundwater, and thus help explore solutions to improve the sustainability of global food supply.

  7. Groundwater and climate change research scoping study

    OpenAIRE

    Jackson, C. R.; Cheetham, M.; Guha, P

    2006-01-01

    This scoping study has reviewed much of the published literature in the field of climate change and groundwater research. Whilst it is not exhaustive with regard to groundwater quality issues, most of the published literature relating to climate change and groundwater resources, particularly in the UK, is covered. Further work is required to identify current research needs relating to the effects of climate change on groundwater quality. The study of the effects of climate chan...

  8. Application of hydrogeology and groundwater-age estimates to assess the travel time of groundwater at the site of a landfill to the Mahomet Aquifer, near Clinton, Illinois

    Science.gov (United States)

    Kay, Robert T.; Buszka, Paul M.

    2016-03-02

    sampled by this study. That result indicated that nearly all groundwater sampled from well G53S entered the aquifer as recharge before 1953. Tritium was detected in a trace concentration in one sample from a second monitoring well open to the upper part of the Radnor Till Member (well G07S; 0.11 ± 0.09 tritium units), and not detected in samples collected from two monitoring wells open to a sand deposit in the lower part of the Radnor Till Member, from two samples collected from two monitoring wells open to the Organic Soil unit, and in two samples collected from a production well screened in the middle of the Mahomet aquifer (a groundwater sample and a sequential replicate sample). The lack of tritium in five of the six groundwater samples collected from the shallow permeable units beneath CLU#3 site and the two samples from the one Mahomet aquifer well indicates an absence of post-1952 recharge. Groundwater-flow paths that could contribute post-1952 recharge to the lower part of the Radnor Till Member, the Organic Soil unit, or the Mahomet aquifer at the CLU#3 are not indicated by these data.Hypothetical two-part mixtures of tritium-dead, pre-1953 recharge water and decay-corrected tritium concentrations in post-1952 recharge were computed and compared with tritium analyses in groundwater sampled from monitoring wells at the CLU#3 site to evaluate whether tritium concentrations in groundwater could be represented by mixtures involving some post-1952 recharge. Results from the hypothetical two-part mixtures indicate that groundwater from monitoring well (G53S) was predominantly composed of pre-1953 recharge and that if present, younger, post-1955 recharge, contributed less than 2.5 percent to that sample. The hypothetical two-part mixing results also indicated that very small amounts of post-1952 recharge composing less than about 2.5 percent of the sample volume could not be distinguished in groundwater samples with tritium concentrations less than about 0.15 TU

  9. Subsidence Serves as an Indicator of Groundwater Arsenic Risk in the San Joaquin Valley, California

    Science.gov (United States)

    Smith, R.; Knight, R. J.; Fendorf, S. E.

    2016-12-01

    Groundwater arsenic concentrations dominantly result from anaerobic conditions. Within aquifers, clays are typically the major hosts of solid-phase arsenic, and clay layers often have restricted oxygen supply, resulting in anaerobic conditions and the concomitant relase of arsenic to groundwater. But it is not until water is drawn from the clay layers, through over-pumping of aquifers, that arsenic enters the water supply. Due to the mechanical properties of clays, the volume of groundwater withdrawn is effectively approximated by their vertical deformation, the sum of which is expressed at the surface as subsidence. As a result, subsidence can serve as an indicator, or "early warning system", of the presence of arsenic in the pumped groundwater. In the San Joaquin Valley of California, there has been significant subsidence due to groundwater extraction from clays for nearly a century. Historical subsidence in this area has been measured with leveling surveys, GPS and extensometers, and has been reproduced in groundwater models. More recent subsidence can be measured directly using Interferometric Synthetic Aperture Radar (InSAR). We use recent (post-2007) arsenic level data from the southern portion of the San Joaquin Valley to train a random forest model. Predictors in the model include historical (pre-2002) estimates of subsidence, more recent (2007-2011) InSAR estimates of subsidence, and other predictors representing additional mechanisms that could affect arsenic levels in groundwater, such as groundwater flow, redox potential and position in the basin. We find that recent subsidence is a strong predictor of arsenic levels; historical subsidence could have some impact but is less significant. These results indicate that avoiding over-pumping of the aquifer may improve water quality over a time period on the order of 10 years. Incorporating subsidence into arsenic prediction maps can improve our ability to identify and manage areas that have a higher risk of

  10. Complexed iron removal from groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Munter, R.; Ojaste, H.; Sutt, J. [Tallinn Technical University, Tallinn (Estonia). Dept. of Environmental & Chemical Technology

    2005-07-01

    The paper demonstrates an intensive work carried out and results obtained on the pilot plant of the City of Kogalym Water Treatment Station (Tjumen, Siberia, Russian Federation) to elaborate on a contemporary nonreagent treatment technology for the local iron-rich groundwater. Several filter materials (Birm, Pyrolox, hydroanthracite, Everzit, granulated activated carbon) and chemical oxidants (ozone, chlorine, hydrogen peroxide, oxygen, and potassium permanganate) were tested to solve the problem with complexed iron removal from groundwater. The final elaborated technology consists of raw water intensive aeration in the gas-degas treatment unit followed by sequential filtration through hydroanthracite and the special anthracite Everzit.

  11. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2014-01-01

    Terrestrial water storage (TWS) comprises groundwater, soil moisture, surface water, snow,and ice. Groundwater typically varies more slowly than the other TWS components because itis not in direct contact with the atmosphere, but often it has a larger range of variability onmultiannual timescales (Rodell and Famiglietti, 2001; Alley et al., 2002). In situ groundwaterdata are only archived and made available by a few countries. However, monthly TWSvariations observed by the Gravity Recovery and Climate Experiment (GRACE; Tapley et al.,2004) satellite mission, which launched in 2002, are a reasonable proxy for unconfinedgroundwater at climatic scales.

  12. Mapping groundwater quality in the Netherlands

    NARCIS (Netherlands)

    Pebesma, Edzer Jan

    2001-01-01

    Groundwater quality is the suitability of groundwater for a certain purpose (e.g. for human consumption), and is mostly determined by its chemical composition. Pollution from agricultural and industrial origin threatens the groundwater quality in the Netherlands. Locally, this pollution is me

  13. Groundwater: Illinois' Buried Treasure. Education Activity Guide.

    Science.gov (United States)

    Environmental Education Association of Illinois, Chicago.

    Groundwater is an extremely valuable resource that many feel has been too long neglected and taken for granted. There is growing recognition in Illinois and throughout the United States that comprehensive groundwater protection measures are vital. Illinois embarked on a course in protecting groundwater resources with the passage of the Illinois…

  14. Geochemical modelling baseline compositions of groundwater

    DEFF Research Database (Denmark)

    Postma, Diederik Jan; Kjøller, Claus; Andersen, Martin Søgaard

    2008-01-01

    Reactive transport models, were developed to explore the evolution in groundwater chemistry along the flow path in three aquifers; the Triassic East Midland aquifer (UK), the Miocene aquifer at Valreas (F) and the Cretaceous aquifer near Aveiro (P). All three aquifers contain very old groundwaters...... of the evolution in natural baseline properties in groundwater....

  15. Groundwater: Illinois' Buried Treasure. Education Activity Guide.

    Science.gov (United States)

    Environmental Education Association of Illinois, Chicago.

    Groundwater is an extremely valuable resource that many feel has been too long neglected and taken for granted. There is growing recognition in Illinois and throughout the United States that comprehensive groundwater protection measures are vital. Illinois embarked on a course in protecting groundwater resources with the passage of the Illinois…

  16. Detection and Remediation of Groundwater Pollution

    Institute of Scientific and Technical Information of China (English)

    王杰

    2016-01-01

    Groundwater is an important part of the water cycle and is also widely used as sources of drinking water. With the increasing de?velopment of groundwater exploitation, the pollution is becoming more and more serious. This paper talks about the main research direc?tions of groundwater pollution, the detection, the remediation and some conclusions.

  17. Groundwater and geothermal: urban district heating applications

    Energy Technology Data Exchange (ETDEWEB)

    Mounts, R.; Frazier, A.; Wood, E.; Pyles, O.

    1982-01-01

    This report describes how several cities use groundwater and geothermal energy in district heating systems. It begins with groundwater, introducing the basic technology and techniques of development, and describing two case studies of cities with groundwater-based district heating systems. The second half of the report consists of three case studies of cities with district heating systems using higher temperature geothermal resources.

  18. State space modeling of groundwater fluctuations

    NARCIS (Netherlands)

    Berendrecht, W.L.

    2004-01-01

    Groundwater plays an important role in both urban and rural areas. It is therefore essential to monitor groundwater fluctuations. However, data that becomes available need to be analyzed further in order to extract specific information on the groundwater system. Until recently, simple linear time se

  19. Sensitivity studies of unsaturated groundwater flow modeling for groundwater travel time calculations at Yucca Mountain, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Altman, S.J.; Ho, C.K.; Arnold, B.W.; McKenna, S.A. [Sandia National Labs., Albuquerque, NM (United States)

    1996-12-01

    Unsaturated flow has been modeled through four cross-sections at Yucca Mountain, Nevada, for the purpose of determining groundwater particle travel times from the potential repository to the water table. This work will be combined with the results of flow modeling in the saturated zone for the purpose of evaluating the suitability of the potential repository under the criteria of 10CFR960. One criterion states, in part, that the groundwater travel time (GWTT) from the repository to the accessible environment must exceed 1,000 years along the fastest path of likely and significant radionuclide travel. Sensitivity analyses have been conducted for one geostatistical realization of one cross-section for the purpose of (1) evaluating the importance of hydrological parameters having some uncertainty (infiltration, fracture-matrix connectivity, fracture frequency, and matrix air entry pressure or van Genuchten {alpha}); and (2) examining conceptual models of flow by altering the numerical implementation of the conceptual model (dual permeability (DK) and the equivalent continuum model (ECM)). Results of comparisons of the ECM and DK model are also presented in Ho et al.

  20. Focus on CSIR research in pollution waste: CSIR Groundwater research into mine closure strategies

    CSIR Research Space (South Africa)

    Turton, A

    2007-08-01

    Full Text Available (i.e. post-life-of-mine). The potential social, financial and environmental benefits of this shift are significant, these extending to the community, mining houses, and regulatory authorities, alike. The CSIR Groundwater team is currently working...

  1. Magnetic properties changes due to hydrocarbon contaminated groundwater table fluctuations

    Science.gov (United States)

    Ameen, Nawrass

    2013-04-01

    This study aims to understand the mechanisms and conditions which control the formation and transformation of ferro(i)magnetic minerals caused by hydrocarbon contaminated groundwater, in particular in the zone of fluctuating water levels. The work extends previous studies conducted at the same site. The study area is a former military air base at Hradčany, Czech Republic (50°37'22.71"N, 14°45'2.24"E). The site was heavily contaminated with petroleum hydrocarbons, due to leaks in petroleum storage tanks and jet fuelling stations over years of active use by the Soviet Union, which closed the base in 1991. The site is one of the most important sources of high quality groundwater in the Czech Republic. In a previous study, Rijal et al. (2010) concluded that the contaminants could be flushed into the sediments as the water level rose due to remediation processes leading to new formation of magnetite. In this previous study three different locations were investigated; however, from each location only one core was obtained. In order to recognize significant magnetic signatures versus depth three cores from each of these three locations were drilled in early 2012, penetrating the unsaturated zone, the groundwater fluctuation (GWF) zone and extending to about one meter below the groundwater level (~2.3 m depth at the time of sampling). Magnetic susceptibility (MS) profiles combined with other magnetic properties were analyzed to obtain a significant depth distribution of the ferro(i)magnetic concentration. Sediment properties, hydrocarbon content and bacterial activity were additionally studied. The results show that the highest ferrimagnetic mineral concentrations exist between 1.4-1.9 m depth from the baseline which is interpreted as the top of the GWF zone. Spikes of MS detected in the previous studies turned out to represent small-scale isolated features, but the trend of increasing MS values from the lowermost position of the groundwater table upward was verified

  2. Subsidence due to Excessive Groundwater Withdrawal in the San Joaquin Valley, California

    Science.gov (United States)

    Corbett, F.; Harter, T.; Sneed, M.

    2011-12-01

    Francis Corbett1, Thomas Harter1 and Michelle Sneed2 1Department of Land Air and Water Resources, University of California, Davis. 2U.S. Geological Survey Western Remote Sensing and Visualization Center, Sacramento. Abstract: Groundwater development within the Central Valley of California began approximately a century ago. Water was needed to supplement limited surface water supplies for the burgeoning population and agricultural industries, especially within the arid but fertile San Joaquin Valley. Groundwater levels have recovered only partially during wet years from drought-induced lows creating long-term groundwater storage overdraft. Surface water deliveries from Federal and State sources led to a partial alleviation of these pressure head declines from the late 1960s. However, in recent decades, surface water deliveries have declined owing to increasing environmental pressures, whilst water demands have remained steady. Today, a large portion of the San Joaquin Valley population, and especially agriculture, rely upon groundwater. Groundwater levels are again rapidly declining except in wet years. There is significant concern that subsidence due to groundwater withdrawal, first observed at a large scale in the middle 20th century, will resume as groundwater resources continue to be depleted. Previous subsidence has led to problems such as infrastructure damage and flooding. To provide a support tool for groundwater management on a naval air station in the southern San Joaquin Valley (Tulare Lake Basin), a one-dimensional MODFLOW subsidence model covering the period 1925 to 2010 was developed incorporating extensive reconstruction of historical subsidence and water level data from various sources. The stratigraphy used for model input was interpreted from geophysical logs and well completion reports. Gaining good quality data proved problematic, and often values needed to be estimated. In part, this was due to the historical lack of awareness/understanding of

  3. Remediation of Chlorinated Solvent Plumes Using In-Situ Air Sparging—A 2-D Laboratory Study

    Directory of Open Access Journals (Sweden)

    Jeffrey A. Adams

    2011-06-01

    Full Text Available In-situ air sparging has evolved as an innovative technique for soil and groundwater remediation impacted with volatile organic compounds (VOCs, including chlorinated solvents. These may exist as non-aqueous phase liquid (NAPL or dissolved in groundwater. This study assessed: (1 how air injection rate affects the mass removal of dissolved phase contamination, (2 the effect of induced groundwater flow on mass removal and air distribution during air injection, and (3 the effect of initial contaminant concentration on mass removal. Dissolved-phase chlorinated solvents can be effectively removed through the use of air sparging; however, rapid initial rates of contaminant removal are followed by a protracted period of lower removal rates, or a tailing effect. As the air flow rate increases, the rate of contaminant removal also increases, especially during the initial stages of air injection. Increased air injection rates will increase the density of air channel formation, resulting in a larger interfacial mass transfer area through which the dissolved contaminant can partition into the vapor phase. In cases of groundwater flow, increased rates of air injection lessened observed downward contaminant migration effect. The air channel network and increased air saturation reduced relative hydraulic conductivity, resulting in reduced groundwater flow and subsequent downgradient contaminant migration. Finally, when a higher initial TCE concentration was present, a slightly higher mass removal rate was observed due to higher volatilization-induced concentration gradients and subsequent diffusive flux. Once concentrations are reduced, a similar tailing effect occurs.

  4. Surface-groundwater interactions in hard rocks in Sardon Catchment of western Spain: an integrated modeling approach

    Science.gov (United States)

    Hassan, S.M. Tanvir; Lubczynski, Maciek W.; Niswonger, Richard G.; Zhongbo, Su

    2014-01-01

    The structural and hydrological complexity of hard rock systems (HRSs) affects dynamics of surface–groundwater interactions. These complexities are not well described or understood by hydrogeologists because simplified analyses typically are used to study HRSs. A transient, integrated hydrologic model (IHM) GSFLOW (Groundwater and Surface water FLOW) was calibrated and post-audited using 18 years of daily groundwater head and stream discharge data to evaluate the surface–groundwater interactions in semi-arid, ∼80 km2 granitic Sardon hilly catchment in Spain characterized by shallow water table conditions, relatively low storage, dense drainage networks and frequent, high intensity rainfall. The following hydrological observations for the Sardon Catchment, and more generally for HRSs were made: (i) significant bi-directional vertical flows occur between surface water and groundwater throughout the HRSs; (ii) relatively large groundwater recharge represents 16% of precipitation (P, 562 mm.y−1) and large groundwater exfiltration (∼11% of P) results in short groundwater flow paths due to a dense network of streams, low permeability and hilly topographic relief; deep, long groundwater flow paths constitute a smaller component of the water budget (∼1% of P); quite high groundwater evapotranspiration (∼5% of P and ∼7% of total evapotranspiration); low permeability and shallow soils are the main reasons for relatively large components of Hortonian flow and interflow (15% and 11% of P, respectively); (iii) the majority of drainage from the catchment leaves as surface water; (iv) declining 18 years trend (4.44 mm.y−1) of groundwater storage; and (v) large spatio-temporal variability of water fluxes. This IHM study of HRSs provides greater understanding of these relatively unknown hydrologic systems that are widespread throughout the world and are important for water resources in many regions.

  5. Global Groundwater related Risk Indicators: quantifying groundwater stress and groundwater table decline (1990-2010) at global scale

    Science.gov (United States)

    Faneca Sanchez, Marta; Sutanudjaja, Edwin; Kuijper, Marijn; Bierkens, Marc

    2016-04-01

    Groundwater is an invisible but indispensable resource for the economic development of many countries. Due to the need for this resource, in many cases it is exploited under severe pressure and the exploitation can become not sustainable. The non-sustainable exploitation of water is a well-known problem on both regional and global scales. However, most currently-available assessments on water stress still mostly focus on surface water and on water balances. In this work, we presented two global maps of groundwater risk indicators: an updated version of the groundwater stress (Gleeson et al., 2011, DOI: 10.1038/nature11295) and an indicator on groundwater table decline for the period 1990-2010. To calculate both indicators, we used the updated PCR-GLOBWB model output at 5 arcmin resolution (about 10 km at the equator), that is extended with an offline coupling to a global groundwater MODFLOW model. PCR-GLOBWB simulates daily river discharge and groundwater recharge, as well as surface water and groundwater abstraction rates. The latter are estimated internally within the model based on the simulation of their availabilities and water demands for irrigation and other sectors. The daily output of PCR-GLOBWB would then be aggregated to the monthly resolution and used to force the MODFLOW groundwater model resolving spatio-temporal groundwater table dynamics, incorporating the simulated groundwater abstraction of PCR-GLOBWB. Using the PCR-GLOBWB and MODFLOW simulation results from the period 1990-2010, we then quantified groundwater stress and assessed the groundwater table decline. Results are presented on four different spatial scales: 5 arcmin pixel, drainage/sub-catchment unit, state level, and major aquifer unit. The maps clearly show where groundwater is under stress, where there is a trend in the drop of the groundwater table, the slope of the drop and the significance of it.

  6. Groundwater regulation and integrated planning

    Science.gov (United States)

    Quevauviller, Philippe; Batelaan, Okke; Hunt, Randall J.

    2016-01-01

    The complex nature of groundwater and the diversity of uses and environmental interactions call for emerging groundwater problems to be addressed through integrated management and planning approaches. Planning requires different levels of integration dealing with: the hydrologic cycle (the physical process) including the temporal dimension; river basins and aquifers (spatial integration); socioeconomic considerations at regional, national and international levels; and scientific knowledge. The great natural variation in groundwater conditions obviously affects planning needs and options as well as perceptions from highly localised to regionally-based approaches. The scale at which planning is done therefore needs to be carefully evaluated against available policy choices and options in each particular setting. A solid planning approach is based on River Basin Management Planning (RBMP), which covers: (1) objectives that management planning are designed to address; (2) the way various types of measures fit into the overall management planning; and (3) the criteria against which the success or failure of specific strategies or interventions can be evaluated (e.g. compliance with environmental quality standards). A management planning framework is to be conceived as a “living” or iterated document that can be updated, refined and if necessary changed as information and experience are gained. This chapter discusses these aspects, providing an insight into European Union (EU), United States and Australia groundwater planning practices.

  7. Groundwater Resources: Investigation and Development

    Science.gov (United States)

    Anderson, Mary P.

    A glance through the table of contents of this volume might suggest that it is yet another introductory text on principles of groundwater hydrology. All of the usual basic topics are covered including definitions of terms and concepts, aquifer types, drilling methods, and pumping tests. But partly because this book is intended for practicing groundwater consultants rather than students, other less elementary topics such as environmental isotope techniques, geochemical methods, interpretation and utilization of spring flow, geophysical methods, and groundwater balances are also included.According to the preface, ‘practical applicability’ is stressed ‘to show how groundwater investigations should be conducted using a systematic, well-directed effort’ and to describe ‘… what to do, what to avoid, and what kind of results one can reasonably expect …’ While this book was published as part of a series of monographs on water pollution, it is more in the nature of a handbook than a true monograph. That is, it is not an in-depth treatment of a single topic but presents a broad introduction to the ways in

  8. Adsorptive Iron Removal from Groundwater

    NARCIS (Netherlands)

    Sharma, S.K.

    2001-01-01

    Iron is commonly present in groundwater worldwide. The presence of iron in drinking water is not harmful to human health, however it is undesirable because of the associated aesthetic and operational problems, namely: bad taste, colour, stains on laundry and plumbing fixtures, and aftergrowth in the

  9. Adsorptive iron removal from groundwater

    NARCIS (Netherlands)

    Sharma, S.K.

    2001-01-01

    Iron is commonly present in groundwater worldwide. The presence of iron in the water supply is not harmful to human health, however it is undesirable. Bad taste, discoloration, staining, deposition in the distribution system leading to aftergrowth, and incidences of high turbidity are some

  10. SUSPICIOUS POST

    CERN Multimedia

    Relations with the Host States Service

    2001-01-01

    If you receive a suspicious letter or package in the post, please do not open it and contact the Fire Brigade Tel. 74444. They will contact the CERN Medical Service. This is especially important in today's current situation with regard to the Anthrax scare. For further information, the Permanent Mission of Switzerland to the International Organisations in Geneva recommends the following web sites:   http://www.admin.ch/ch/f/cf/brennpunkt/03.html http://www.who.int/emc-documents/zoonoses/whoemczdi986c.html

  11. Phytoremediation of Groundwater at Air Force Plant 4, Carswell, Texas

    Science.gov (United States)

    2003-09-01

    swings in soil water potential through transpiration and by the continual addition of water-retentive organic matter. In essence , the 6 plant-microbe...ability of trees to act as pumps was noted in the late 19th century when Eucalyptus trees were planted in Italy and Algeria to dry up marshes. The...development of short rotation crops such as cottonwoods, hybrid poplar, willow, eucalyptus , or other energy crops, requires consideration of operational

  12. Groundwater flow modelling of periods with temperate climate conditions - Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Joyce, Steven; Simpson, Trevor; Hartley, Lee; Applegate, David; Hoek, Jaap; Jackson, Peter; Swan, David (Serco Technical Consulting Services (United Kingdom)); Marsic, Niko (Kemakta Konsult AB (Sweden)); Follin, Sven (SF GeoLogic AB (Sweden))

    2010-11-15

    As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different climate conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. This report concerns the modelling of a repository at the Forsmark site during temperate conditions; i.e. from post-closure and throughout the temperate period up until the receding shoreline leaves the modelling domain at around 12,000 AD. The collation and implementation of onsite hydrogeological and hydrogeochemical data from previous reports are used in the construction of a hydrogeological base case (reference case conceptualisation) and then in an examination of various areas of uncertainty within the current understanding by a series of model variants. The hydrogeological base case models at three different scales, 'repository', 'site' and 'regional', make use of continuous porous medium (CPM), equivalent continuous porous medium (ECPM) and discrete fracture network (DFN) models. The use of hydrogeological models allow for the investigation of the groundwater flow from a deep disposal facility to the biosphere and for the calculation of performance measures that will provide an input to the site performance assessment. The focus of the study described in this report has been to perform numerical simulations of the hydrogeological system from post-closure and throughout the temperate period. Besides providing quantitative results for the immediate temperate period following post-closure, these results are also intended to give a qualitative indication of the evolution of the groundwater system during future temperate periods within an ongoing cycle of glacial/inter-glacial events

  13. Quantifying renewable groundwater stress with GRACE

    Science.gov (United States)

    Richey, Alexandra S.; Thomas, Brian F.; Lo, Min‐Hui; Reager, John T.; Voss, Katalyn; Swenson, Sean; Rodell, Matthew

    2015-01-01

    Abstract Groundwater is an increasingly important water supply source globally. Understanding the amount of groundwater used versus the volume available is crucial to evaluate future water availability. We present a groundwater stress assessment to quantify the relationship between groundwater use and availability in the world's 37 largest aquifer systems. We quantify stress according to a ratio of groundwater use to availability, which we call the Renewable Groundwater Stress ratio. The impact of quantifying groundwater use based on nationally reported groundwater withdrawal statistics is compared to a novel approach to quantify use based on remote sensing observations from the Gravity Recovery and Climate Experiment (GRACE) satellite mission. Four characteristic stress regimes are defined: Overstressed, Variable Stress, Human‐dominated Stress, and Unstressed. The regimes are a function of the sign of use (positive or negative) and the sign of groundwater availability, defined as mean annual recharge. The ability to mitigate and adapt to stressed conditions, where use exceeds sustainable water availability, is a function of economic capacity and land use patterns. Therefore, we qualitatively explore the relationship between stress and anthropogenic biomes. We find that estimates of groundwater stress based on withdrawal statistics are unable to capture the range of characteristic stress regimes, especially in regions dominated by sparsely populated biome types with limited cropland. GRACE‐based estimates of use and stress can holistically quantify the impact of groundwater use on stress, resulting in both greater magnitudes of stress and more variability of stress between regions. PMID:26900185

  14. Trend Analyses of Nitrate in Danish Groundwater

    Science.gov (United States)

    Hansen, B.; Thorling, L.; Dalgaard, T.; Erlandsen, M.

    2012-04-01

    This presentation assesses the long-term development in the oxic groundwater nitrate concentration and nitrogen (N) loss due to intensive farming in Denmark. Firstly, up to 20-year time-series from the national groundwater monitoring network enable a statistically systematic analysis of distribution, trends and trend reversals in the groundwater nitrate concentration. Secondly, knowledge about the N surplus in Danish agriculture since 1950 is used as an indicator of the potential loss of N. Thirdly, groundwater recharge CFC (Chlorofluorocarbon) age determination allows linking of the first two dataset. The development in the nitrate concentration of oxic groundwater clearly mirrors the development in the national agricultural N surplus, and a corresponding trend reversal is found in groundwater. Regulation and technical improvements in the intensive farming in Denmark have succeeded in decreasing the N surplus by 40% since the mid 1980s while at the same time maintaining crop yields and increasing the animal production of especially pigs. Trend analyses prove that the youngest (0-15 years old) oxic groundwater shows more pronounced significant downward nitrate trends (44%) than the oldest (25-50 years old) oxic groundwater (9%). This amounts to clear evidence of the effect of reduced nitrate leaching on groundwater nitrate concentrations in Denmark. Are the Danish groundwater monitoring strategy obtimal for detection of nitrate trends? Will the nitrate concentrations in Danish groundwater continue to decrease or are the Danish nitrate concentration levels now appropriate according to the Water Framework Directive?

  15. Thermal management of an urban groundwater body

    Directory of Open Access Journals (Sweden)

    J. Epting

    2012-06-01

    Full Text Available This study presents a management concept for the sustainable thermal use of an urban groundwater body. The concept is designed to be applied for shallow thermal groundwater use and is based on (1 a characterization of the present thermal state of the investigated urban groundwater body; (2 the definition of development goals for specific aquifer regions, including future aquifer use and urbanization; and (3 an evaluation of the thermal use potential for these regions.

    The investigations conducted in the city of Basel (Switzerland focus on thermal processes down-gradient of thermal groundwater use, effects of heated buildings in the aquifer as well as the thermal influence of river-groundwater interaction. Investigation methods include: (1 short- and long-term data analysis; (2 high-resolution multilevel groundwater temperature monitoring; as well as (3 3-D numerical groundwater flow and heat-transport modeling and scenario development. The combination of these methods allows quantifying the thermal influence on the investigated urban groundwater body, including the influences of thermal groundwater use and additional heat from urbanization. Subsequently, management strategies for minimizing further groundwater temperature increase, targeting "potential natural" groundwater temperatures for specific aquifer regions and exploiting the thermal use potential are discussed.

  16. Aquifer-Circulating Water Curtain Cultivation System To Recover Groundwater Level And Temperature

    Science.gov (United States)

    Kim, Y.; Ko, K.; Chon, C.; Oh, S.

    2011-12-01

    Groundwater temperature, which generally ranges 14 to 16 degree of Celsius all year long, can be said to be 'constant' compared to the amplitude of daily variation of air temperature or surface water. Water curtain cultivating method utilizes this 'constant' groundwater temperature to warm up the inside of greenhouse during winter night by splash groundwater on the roof of inner greenhouse. The area of water curtain cultivation system have increased up to 107.5 square kilometers as of 2006 since when it is first introduced to South Korea in 1984. Groundwater shortage problem became a great issue in a concentrated water curtain cultivation area because the pumped and splashed groundwater is abandoned to nearby stream and natural recharge rate is reduced by greenhouses. The amount of groundwater use for water curtain cultivation system in South Korea is calculated to be 587 million cubic meters which is 35% of national agricultural use of groundwater. A new water curtain cultivation system coupled with aquifer circulating of the splashed groundwater and greenhouse roof-top rainwater harvesting is developed and applied to field site in Nonsan-si, Chungnam province to minimize groundwater shortage problem and recover groundwater level. The aquifer circulating water curtain cultivation system is consist of a pumping well and a injection well of 80 m deep, groundwater transfer and splashing system, recovery tank and rainwater collecting waterway. The distance between injection and pumping well is 15 m and an observation well is installed in the middle of the wells. To characterize hydrogeological properties of this site, hydraulic test such as pumping tests and tracer tests with dye tracer, thermal tracer and ion tracer. Once the integrated system is constructed in this site, hydraulic head in all the wells and temperature of air, recovery tank and groundwater in all the wells are monitored during the operation for 3months in winter season. Hydraulic test and tracer

  17. The origin of groundwater composition in the Pampeano Aquifer underlying the Del Azul Creek basin, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Zabala, M.E., E-mail: mzabala@faa.unicen.edu.ar [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, C1033AAJ Ciudad Autónoma de Buenos Aires (Argentina); Instituto de Hidrología de Llanuras “Dr. Eduardo J. Usunoff”, Av. República Italia 780, 7300 Azul, Provincia Buenos Aires (Argentina); Manzano, M., E-mail: marisol.manzano@upct.es [Escuela de Ingeniería de Caminos, Canales y Puertos y de Ingeniería de Minas, Universidad Politécnica de Cartagena, P° de Alfonso XIII 52, E-30203 Cartagena (Spain); Vives, L., E-mail: lvives@faa.unicen.edu.ar [Instituto de Hidrología de Llanuras “Dr. Eduardo J. Usunoff”, Av. República Italia 780, 7300 Azul, Provincia Buenos Aires (Argentina)

    2015-06-15

    The Pampean plain is the most productive region in Argentina. The Pampeano Aquifer beneath the Pampean plain is used mostly for drinking water. The study area is the sector of the Pampeano Aquifer underlying the Del Azul Creek basin, in Buenos Aires province. The main objective is to characterize the chemical and isotopic compositions of groundwater and their origin on a regional scale. The methodology used involved the identification and characterization of potential sources of solutes, the study of rain water and groundwater chemical and isotopic characteristics to deduce processes, the development of a hydrogeochemical conceptual model, and its validation by hydrogeochemical modelling with PHREEQC. Groundwater samples come mostly from a two-depth monitoring network of the “Dr. Eduardo J. Usunoff” Large Plains Hydrology Institute (IHLLA). Groundwater salinity increases from SW to NE, where groundwater is saline. In the upper basin groundwater is of the HCO{sub 3}-Ca type, in the middle basin it is HCO{sub 3}-Na, and in the lower basin it is ClSO{sub 4}–NaCa and Cl–Na. The main processes incorporating solutes to groundwater during recharge in the upper basin are rain water evaporation, dissolution of CO{sub 2}, calcite, dolomite, silica, and anorthite; cationic exchange with Na release and Ca and Mg uptake, and clay precipitation. The main processes modifying groundwater chemistry along horizontal flow at 30 m depth from the upper to the lower basin are cationic exchange, dissolution of silica and anorthite, and clay precipitation. The origin of salinity in the middle and lower basin is secular evaporation in a naturally endorheic area. In the upper and middle basins there is agricultural pollution. In the lower basin the main pollution source is human liquid and solid wastes. Vertical infiltration through the boreholes annular space during the yearly flooding stages is probably the pollution mechanism of the samples at 30 m depth. - Highlights: • The

  18. Tracing and quantifying groundwater inflow into lakes using a simple method for radon-222 analysis

    Directory of Open Access Journals (Sweden)

    T. Kluge

    2007-09-01

    Full Text Available Due to its high activities in groundwater, the radionuclide 222Rn is a sensitive natural tracer to detect and quantify groundwater inflow into lakes, provided the comparatively low activities in the lakes can be measured accurately. Here we present a simple method for radon measurements in the low-level range down to 3 Bq m−3, appropriate for groundwater-influenced lakes, together with a concept to derive inflow rates from the radon budget in lakes. The analytical method is based on a commercially available radon detector and combines the advantages of established procedures with regard to efficient sampling and sensitive analysis. Large volume (12 l water samples are taken in the field and analyzed in the laboratory by equilibration with a closed air loop and alpha spectrometry of radon in the gas phase. After successful laboratory tests, the method has been applied to a small dredging lake without surface in- or outflow in order to estimate the groundwater contribution to the hydrological budget. The inflow rate calculated from a 222Rn balance for the lake is around 530 m³ per day, which is comparable to the results of previous studies. In addition to the inflow rate, the vertical and horizontal radon distribution in the lake provides information on the spatial distribution of groundwater inflow to the lake. The simple measurement and sampling technique encourages further use of radon to examine groundwater-lake water interaction.

  19. Shaping the contours of groundwater governance in India

    OpenAIRE

    Kulkarni, Himanshu; Shah, Mihir; P.S. Vijay Shankar

    2015-01-01

    Study region: India. Study focus: India's groundwater dependence and the crises of depletion and contamination of groundwater resources require the development of a robust groundwater dependence framework. Understanding the challenges of developing a groundwater governance framework for regions of extensive groundwater development versus relatively less-developed areas of groundwater development is important. The groundwater typology is a function of both, the hydrogeological aspects of gr...

  20. Near shore groundwater acidification during and after a hydrological drought in the Lower Lakes, South Australia

    Science.gov (United States)

    Leyden, Emily; Cook, Freeman; Hamilton, Benjamin; Zammit, Benjamin; Barnett, Liz; Lush, Ann Marie; Stone, Dylan; Mosley, Luke

    2016-06-01

    An extreme hydrological drought in the Lower Lakes of the Murray-Darling Basin (Ramsar listed site) resulted in exposure of large areas of lake bed (25% of pre-drought lake area), containing the reduced iron (Fe) sulfide mineral pyrite. The pyrite oxidised and the resulting acidification (pH quality was undertaken for six years from 2009 (drought) to 2014 (4 years post-reinundation). Acidic (pH 3-5) groundwater was recorded at three of the four piezometer locations and included sites close to the lake water. The acidic groundwater (0.5-2 m below lake bed) at these sites is likely to have originated from the transport of acid from the upper oxidised sediment layer formed during the drought. High soluble metal (Fe, Al, Mn) levels were also recorded at acidic locations. Acidic shallow groundwater has persisted at many sites for over 4 years following reinundation post-drought, and is likely due to slow diffusion and limited sulfate reduction. Increases in dissolved Fe and Mn with decreases in redox potential suggest that reductive dissolution of Fe and Mn hydrous oxides and Fe oxy-hydroxysulfate minerals (e.g. jarosite) occurred post-drought. Groundwater hydraulic head gradients were low, indicating there was limited potential for groundwater to discharge to the lake. The hydraulic gradients at all locations were dynamic with complex relationships along the near-shore environment. The results highlight the long lasting and severe effects on groundwater that can occur following hydrological drought in aquatic environments with sulfidic sediments.

  1. Groundwater Policy Research: Collaboration with Groundwater Conservation Districts in Texas

    OpenAIRE

    Johnson, Jeffrey W.; Johnson, Phillip N.; Guerrero, Bridget L.; Weinheimer, Justin; Amosson, Stephen H.; Almas, Lal K.; Golden, Bill B.; Wheeler-Cook, Erin

    2011-01-01

    The unique nature of the Ogallala Aquifer presents interesting and confounding problems for water policymakers who are coping with changing groundwater rules in Texas. The purpose of this article is to link previous efforts in water policy research for the Ogallala Aquifer in Texas with current collaborations that are ongoing with regional water planners. A chronological progression of economic water modeling efforts for the region is reviewed. The results of two recent collaborative studies ...

  2. Groundwater Policy Research: Collaboration with Groundwater Conservation Districts in Texas

    OpenAIRE

    Johnson, Jeffrey W.; Johnson, Phillip N.; Guerrero, Bridget L.; Weinheimer, Justin; Amosson, Stephen H.; Almas, Lal K.; Golden, Bill B.; Wheeler-Cook, Erin

    2011-01-01

    The unique nature of the Ogallala Aquifer presents interesting and confounding problems for water policymakers who are coping with changing groundwater rules in Texas. The purpose of this article is to link previous efforts in water policy research for the Ogallala Aquifer in Texas with current collaborations that are ongoing with regional water planners. A chronological progression of economic water modeling efforts for the region is reviewed. The results of two recent collaborative studies ...

  3. A co-metabolic approach to groundwater remediation

    Energy Technology Data Exchange (ETDEWEB)

    Palumbo, A.V.; Boerman, P.A.; Strandberg, G.W.; Donaldson, T.L.; Jennings, H.L.; Lucero, A.J.; Herbes, S.E. (Oak Ridge National Lab., TN (United States)); Phelps, T.J.; White, D.C. (Tennessee Univ., Knoxville, TN (United States). Inst. for Applied Microbiology)

    1991-01-01

    In support of the US Department of Energy's (DOE) Integrated Demonstration (Cleanup of Organics in Soils and Groundwater at Non-arid Sites) at the Savannah River Site (SRS), Oak Ridge National Laboratory (ORNL) and the University of Tennessee (UT) are involved in demonstrations of the use of methanotrophs in bioreactors for remediation of contaminated groundwater. In preparation for a field demonstration at ORNL's K-25 Site in Oak Ridge, Tennessee, ORNL is conducting batch experiments, is operating a number of bench-scale bioreactors, has designed pretreatment systems, and has modified a field-scale bioreactor provided by the Air Force Engineering and Services Center for use at the site. UT is operating bench-scale bioreactors with the goal of determining the stability of a trichloroethylene-degrading methanotrophic consortia during shifts in operating conditions (e.g. pH, nutrient inputs, and contaminant mixtures). These activities are all aimed at providing the knowledge base necessary for successful treatment of contaminated groundwater at the SRS and K-25 sites as well as other DOE sites. 18 refs., 1 fig. , 1 tab.

  4. Hydrogeochemical characterization of fluoride rich groundwater of Wailpalli watershed, Nalgonda District, Andhra Pradesh, India.

    Science.gov (United States)

    Reddy, A G S; Reddy, D V; Rao, P N; Prasad, K Maruthy

    2010-12-01

    The groundwater of Nalgonda district is well known for its very high fluoride content for the past five decades. Many researchers have contributed their scientific knowledge to unravel causes for fluoride enrichment of groundwater. In the present paper, an attempt has been made to relate the high fluoride content in the groundwater to hydrogeochemical characterization of the water in a fracture hard rock terrain--the Wailpally watershed. Groundwater samples collected from all the major geomorphic units in pre- and post-monsoon seasons were analyzed for its major ion constituents such as Ca(2+), Mg(2+), Na(+), K(+), CO3-, HCO3-, Cl(-), SO4(-2), NO3-, and F(-). The groundwaters in the watershed have the average fluoride content of 2.79 mg/l in pre-monsoon and 2.83 mg/l in post-monsoon. Fluoride concentration in groundwater does not show perceptible change neither with time nor in space. The ionic dominance pattern is in the order of Na(+) > Ca(2+) > Mg(2+) > K(-) among cations and HCO3- Cl(-) > SO4(-2) NO3- F(-) among anions in pre-monsoon. In post-monsoon, Mg replaces Ca(2+) and NO3- takes the place of SO4(-2). The Modified Piper diagram reflect that the water belong to Ca(+2)-Mg(+2)-HCO3- to Na(+)-HCO3- facies. Negative chloralkali indices in both the seasons prove that ion exchange between Na(+) and K(+) in aquatic solution took place with Ca(+2) and Mg(+2) of host rock. The interpretation of plots for different major ions and molar ratios suggest that weathering of silicate rocks and water-rock interaction is responsible for major ion chemistry of groundwater in Wailpally watershed. Chemical characteristics and evolution of this fluoride-contaminated groundwater is akin to normal waters of other hard rock terrain; hence, it can be concluded that aquifer material play an important role in the contribution of fluoride in to the accompanying water. High fluoride content in groundwater can be attributed to the continuous water-rock interaction during the

  5. Groundwater Availability Within the Salton Sea Basin Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Tompson, A; Demir, Z; Moran, J; Mason, D; Wagoner, J; Kollet, S; Mansoor, K; McKereghan, P

    2008-01-11

    It is widely recognized that increasing demands for water in Southern California are being affected by actions to reduce and redirect the amount of water imported from the Colorado River. In the Imperial Valley region, for example, import reductions will not only affect agricultural users but also could produce significant collateral impacts on the level and quality of water in the Salton Sea, its regional ecology, or even the long term air quality in the greater basin. The notion of using groundwater in the Imperial Valley as an additional source for agricultural or domestic needs, energy production, or Salton Sea restoration efforts, so as to offset reductions in imported water, is not a new concept. Even though it has been discussed recently (e.g., LLNL, 2002), the idea goes back, in part, to several studies performed by the US Department of Interior and other agencies that have indicated that there may be substantial, usable amounts of groundwater in some portions of the Imperial Valley. It has been estimated, for example, that between 1.1 and 3 billion acre-feet (AF) of groundwater lie within the extended, deep basin underlying the valley and Salton Sea region, even though much of it may be unrecoverable or too poor in its quality (Imperial County, 1997). This is a significant volume with respect to the total annual precipitation volume received in California, whose average is close to 200 million (or 0.2 billion) AF per year (DWR, 1998), and especially with respect to the total annual precipitation received in the Salton Sea watershed itself, which we estimate (Appendix A) to be approximately 2.5 million acre feet (MAF) per year. Clearly, a thorough appraisal of the groundwater resources in the Imperial Valley and Salton Sea region--i.e., an assessment of their overall physical availability--will be needed to determine how they can be used and managed to suit new or redirected demands in the region. Development of an improved or updated groundwater assessment

  6. Groundwater Availability Within the Salton Sea Basin Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Tompson, A; Demir, Z; Moran, J; Mason, D; Wagoner, J; Kollet, S; Mansoor, K; McKereghan, P

    2008-01-11

    It is widely recognized that increasing demands for water in Southern California are being affected by actions to reduce and redirect the amount of water imported from the Colorado River. In the Imperial Valley region, for example, import reductions will not only affect agricultural users but also could produce significant collateral impacts on the level and quality of water in the Salton Sea, its regional ecology, or even the long term air quality in the greater basin. The notion of using groundwater in the Imperial Valley as an additional source for agricultural or domestic needs, energy production, or Salton Sea restoration efforts, so as to offset reductions in imported water, is not a new concept. Even though it has been discussed recently (e.g., LLNL, 2002), the idea goes back, in part, to several studies performed by the US Department of Interior and other agencies that have indicated that there may be substantial, usable amounts of groundwater in some portions of the Imperial Valley. It has been estimated, for example, that between 1.1 and 3 billion acre-feet (AF) of groundwater lie within the extended, deep basin underlying the valley and Salton Sea region, even though much of it may be unrecoverable or too poor in its quality (Imperial County, 1997). This is a significant volume with respect to the total annual precipitation volume received in California, whose average is close to 200 million (or 0.2 billion) AF per year (DWR, 1998), and especially with respect to the total annual precipitation received in the Salton Sea watershed itself, which we estimate (Appendix A) to be approximately 2.5 million acre feet (MAF) per year. Clearly, a thorough appraisal of the groundwater resources in the Imperial Valley and Salton Sea region--i.e., an assessment of their overall physical availability--will be needed to determine how they can be used and managed to suit new or redirected demands in the region. Development of an improved or updated groundwater assessment

  7. Calendar year 1996 annual groundwater monitoring report for the Upper East Fork Poplar Creek Hydrogeologic Regime at the U.S. Department of Energy Y-12 Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-01

    This annual monitoring report contains groundwater and surface water monitoring data obtained in the Upper East Fork Poplar Creek Hydrogeologic Regime (East Fork Regime) during calendar year (CY) 1996. The East Fork Regime encompasses several confirmed and suspected sources of groundwater contamination within industrialized areas of the US Department of Energy (DOE) Oak Ridge Y-12 Plant in Bear Creek Valley (BCV) southeast of Oak Ridge, Tennessee. Groundwater and surface water monitoring in the East Fork Regime are performed under the auspices of the Y-12 Plant Groundwater Protection Program (GWPP). Included are the groundwater monitoring data obtained in compliance with the Resource Conservation and Recovery Act (RCRA) post-closure permit for the East Fork Regime issued by the Tennessee Department of Environment and Conservation (TDEC) on August 30, 1996. The post-closure permit addresses post-closure monitoring requirements for two closed RCRA-regulated surface impoundments: the S-3 Ponds and New Hope Pond.

  8. Sustainable in-well vapor stripping: A design, analytical model, and pilot study for groundwater remediation.

    Science.gov (United States)

    Sutton, Patrick T; Ginn, Timothy R

    2014-12-15

    A sustainable in-well vapor stripping system is designed as a cost-effective alternative for remediation of shallow chlorinated solvent groundwater plumes. A solar-powered air compressor is used to inject air bubbles into a monitoring well to strip volatile organic compounds from a liquid to vapor phase while simultaneously inducing groundwater circulation around the well screen. An analytical model of the remediation process is developed to estimate contaminant mass flow and removal rates. The model was calibrated based on a one-day pilot study conducted in an existing monitoring well at a former dry cleaning site. According to the model, induced groundwater circulation at the study site increased the contaminant mass flow rate into the well by approximately two orders of magnitude relative to ambient conditions. Modeled estimates for 5h of pulsed air injection per day at the pilot study site indicated that the average effluent concentrations of dissolved tetrachloroethylene and trichloroethylene can be reduced by over 90% relative to the ambient concentrations. The results indicate that the system could be used cost-effectively as either a single- or multi-well point technology to substantially reduce the mass of dissolved chlorinated solvents in groundwater. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. The groundwater buffering effect on heat waves and precipitation: coupled groundwater-atmosphere simulations over Europe and North America with a WRF-LEAFHYDRO system.

    Science.gov (United States)

    Miguez-Macho, Gonzalo; Gómez, Breogán; Regueiro-Sanfiz, Sabela; Georgescu, Matei

    2016-04-01

    We present coupled atmosphere-hydrology simulations with the WRF regional climate model and the LEAFHYDRO LSM, including groundwater dynamics. Simulations are carried out for the coupled system for the growing season (February to October) over Europe at 2.5km resolution over land and 20km over the atmosphere. Initial conditions for the land surface, groundwater and rivers are from 10 year off-line simulations, performed continuously over the same domain and period, forced by atmospheric data from the Earth2Observe FP7 project. We show that the presence of a shallow water table over portions of the European continent enhances evapotranspiration in dry periods under increasing atmospheric demand. The impact of the coupling between groundwater and the soil vegetation system on land surface fluxes results in decreases in air temperature and an increase in low level mixing ratios, which under certain convective regimes induces more precipitation. We illustrate for the heat wave of 2003 that models that do not include this groundwater buffering effect may enhance significantly the intensity of such temperature extreme cases. The effect on precipitation is mostly seen over inland areas where warm season convection is important. We show with results of additional simulations over North America, where summer convection over the interior of the continent is very relevant, that the effect of groundwater-enhanced evapotranspiration may have a sizeable impact on climate at the global scale.

  10. Water Quality Assessment of Groundwater Resources in Nagpur Region (India Based on WQI

    Directory of Open Access Journals (Sweden)

    P. N. Rajankar

    2009-01-01

    Full Text Available Water quality index (WQI has been calculated for different groundwater sources i.e. dug wells, bore wells and tube wells at Khaperkheda region, Maharashtra (India. Twenty two different sites were selected in post monsoon, winter and summer season. And water quality index was calculated using water quality index calculator given by National Sanitation Foundation (NSF information system. The calculated WQI showed fair water quality rating in post monsoon season which then changed to medium in summer and winter seasons for dug wells, but the bore wells and hand pumps showed medium water quality rating in all seasons where the quality was slightly differs in summer and winter season than post monsoon season, so the reasons to import water quality change and measures to be taken up in terms of groundwater quality management are required.

  11. [Construction of groundwater contamination prevention mapping system].

    Science.gov (United States)

    Wang, Jun-Jie; He, Jiang-Tao; Lu, Yan; Liu, Li-Ya; Zhang, Xiao-Liang

    2012-09-01

    Groundwater contamination prevention mapping is an important component of groundwater contamination geological survey and assessment work, which could provide the basis for making and implementing groundwater contamination prevention planning. A groundwater contamination prevention mapping system was constructed in view of the synthetic consideration on nature perspective derived from groundwater contamination sources and aquifer itself, social-economic perspective, policy perspective derived from outside. During the system construction process, analytic hierarchy process and relevant overlaying principles were used to couple groundwater contamination risk assessment, groundwater value as well as wellhead protection area zoning. Data processing and visualization of mapping results were achieved in the GIS environment. The research on groundwater contamination prevention mapping in Beijing Plain indicated that the final groundwater prevention map was in accordance with the actual conditions and well reflected the priorities of groundwater prevention, which could play a guidance role in designing and implementing further practical prevention and supervision measures. Besides, because of the dynamical properties of the system components, it was suggested to analyze the update frequency of the mapping.

  12. Calendar Year 2016 Annual Groundwater Monitoring Report.

    Energy Technology Data Exchange (ETDEWEB)

    Copland, John R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jackson, Timmie Okchumpulla [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Li, Jun [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mitchell, Michael Marquand [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Skelly, Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-06-01

    Sandia National Laboratories, New Mexico (SNL/NM) is a government-owned/contractoroperated laboratory. National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., manages and operates SNL/NM for the U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA). The DOE/NNSA Sandia Field Office administers the contract and oversees contractor operations at the site. Two types of groundwater surveillance monitoring are conducted at SNL/NM: (1) on a site-wide basis as part of the SNL/NM Long-Term Stewardship (LTS) Program’s Groundwater Monitoring Program (GMP) Groundwater Surveillance Task and (2) on a site-specific groundwater monitoring at LTS/Environmental Restoration (ER) Operations sites with ongoing groundwater investigations. This Annual Groundwater Monitoring Report summarizes data collected during groundwater monitoring events conducted at GMP locations and at the following SNL/NM sites through December 31, 2016: Burn Site Groundwater Area of Concern (AOC); Chemical Waste Landfill; Mixed Waste Landfill; Technical Area-V Groundwater AOC; and the Tijeras Arroyo Groundwater AOC. Environmental monitoring and surveillance programs are required by the New Mexico Environment Department (NMED) and DOE Order 436.1, Departmental Sustainability, and DOE Order 231.1B, Environment, Safety, and Health Reporting.

  13. BIOVENTING - Groundwater Aeration by Discontinuous Oxygen Gas Pulse Injections

    Science.gov (United States)

    Schirmer, M.

    2003-12-01

    Groundwater aeration by discontinuous oxygen gas pulse injections appears to be a promising concept for enhanced natural attenuation of dissolved contaminants that are susceptible for oxygenase enzyme attacks. Oxygen amendments facilitate indigenous microbiota to catabolize groundwater pollutants, such as aromatics, that are considered to be recalcitrant in absence of dissolved oxygen. As a rule, natural attenuation of many pollutants under aerobic conditions is considerably faster than under anaerobic conditions. Thus, enhancing the dissolved oxygen level appears to be worthwhile. In situ aeration of groundwater has been accomplished by air sparging, H2O2-supply, or by utilization of oxygen release compounds. However, continuous aeration of previously anaerobic groundwater is not desirable for several reasons: (a) economic efforts too high, (b) pollutant dislocation towards surface (desired only in air sparging), (c) risk of aquifer clogging (gas clogging, oxidation of ferrous iron, formation of bioslimes). In contrast, discontinuous oxygen gas sparging provides only for periodical groundwater aeration which is followed by microaerobic and suboxic conditions. Microaerobic conditions can prevail spatially (e.g., at plume fringes or within biofilms) or temporarily (e.g., at discontinuous bioventing). They still allow adapted bacteria to transform environmental pollutants to less toxic compounds, e.g., aromatic ring cleavage after dioxygenasis attack. Ring cleavage products, on the other hand, may be degraded more easily by anaerobic consortia than the initial aromatic compounds, making oxygen depletion periods highly intriguing in regard to an initiation of natural attenuation processes at plume fringes. In our work we outline the effect of oxygen depletion conditions on biodegradation of monchlorobenzene (MCB) as they occur subsequently to temporary aeration periods. For microaerobic conditions, relative to the oxygen supply, a stoichiometric transformation of MCB

  14. Alpine Groundwater - Pristine Aquifers Under Threat?

    Science.gov (United States)

    Schneider, P.; Lange, A.

    2014-12-01

    Glacier and permafrost retreat are prominent climate change indicators. However, the characteristics of climate and hydrology in mountain areas remain poorly understood relative to lowland areas. Specifically, not much is known about alpine groundwater, its recharge and water quality variations, as these remote reservoirs are rarely monitored. As global temperatures rise, glaciers and permafrost will continue to retreat forming new sediment deposits and changing infiltration conditions in high alpine terrain. Climate change impacts the hydro-chemical composition of alpine waters, accelerates weathering processes, and potentially triggers mobilization of pollutants. Accordingly, we monitored groundwater quantity and quality parameters of an alpine porous aquifer near the Tiefenbach glacier in the Gotthard Massif in Switzerland. The goal of this research was to assess quality and seasonal storage dynamics of groundwater above the timberline (2000 m). To translate hydrological science into an ecosystem service context, we focused on four attributes: Water quantity: observations of groundwater level fluctuations combined with analysis of contributing water sources based on stable isotope analysis to give a quantitative understanding of origin and amount of water, Water quality: groundwater level, groundwater temperature and electrical conductivity were used as proxies for sampling of hydro-chemical parameters with automated water samplers during primary groundwater recharge periods (snowmelt and rainfall events), Location: Alpine terrain above the timberline, especially recharge into/out of an alpine porous aquifer at a pro-glacial floodplain and Date of annual melt (albedo effect) and timing of flow (snow- and icemelt from May to September) and groundwater recharge during the growing season. The study found that the summer groundwater temperatures depend on the date of annual melt and are more sensitive to climate forcing than lowland groundwater temperatures

  15. Simulating groundwater-induced sewer flooding

    Science.gov (United States)

    Mijic, A.; Mansour, M.; Stanic, M.; Jackson, C. R.

    2016-12-01

    During the last decade, Chalk catchments of southern England experienced severe groundwater flooding. High groundwater levels resulted in the groundwater ingress into the sewer network that led to restricted toilet use and the overflow of diluted, but untreated sewage to road surfaces, rivers and water courses. In response to these events the water and sewerage company Thames Water Utilities Ltd (TWUL) had to allocate significant funds to mitigate the impacts. It was estimated that approximately £19m was spent responding to the extreme wet weather of 2013-14, along with the use of a fleet of over 100 tankers. However, the magnitude of the event was so large that these efforts could not stop the discharge of sewage to the environment. This work presents the analysis of the risk of groundwater-induced sewer flooding within the Chalk catchment of the River Lambourn, Berkshire. A spatially distributed groundwater model was used to assess historic groundwater flood risk and the potential impacts of changes in future climate. We then linked this model to an urban groundwater model to enable us to simulate groundwater-sewer interaction in detail. The modelling setup was used to identify relationships between infiltration into sewers and groundwater levels at specific points on TWUL's sewer network, and to estimate historic and future groundwater flood risk, and how this varies across the catchment. The study showed the significance of understanding the impact of groundwater on the urban water systems, and producing information that can inform a water company's response to groundwater flood risk, their decision making process and their asset management planning. However, the knowledge gained through integrated modelling of groundwater-sewer interactions has highlighted limitations of existing approaches for the simulation of these coupled systems. We conclude this work with number of recommendations about how to improve such hydrological/sewer analysis.

  16. Effect of silica coating on flexural strength of fiber posts

    NARCIS (Netherlands)

    Valandro, LF; Ozcan, M; de Melo, RM; Galhano, GAP; Baldissara, P; Scotti, R; Bottino, MA

    2006-01-01

    Purpose: Fiber-reinforced composite (FRC) posts can be air-abraded to obtain good attachment to the resin cement. This study tested the effect of silica coating on the flexural strength of carbon, opaque, and translucent quartz FRC posts. Materials and Methods: Six experimental groups of FRC posts (

  17. A global-scale two-layer transient groundwater model: Development and application to groundwater depletion

    Science.gov (United States)

    de Graaf, Inge E. M.; van Beek, Rens L. P. H.; Gleeson, Tom; Moosdorf, Nils; Schmitz, Oliver; Sutanudjaja, Edwin H.; Bierkens, Marc F. P.

    2017-04-01

    Groundwater is the world's largest accessible source of freshwater to satisfy human water needs. Moreover, groundwater buffers variable precipitation rates over time, thereby effectively sustaining river flows in times of droughts and evaporation in areas with shallow water tables. In this study, building on previous work, we simulate groundwater head fluctuations and groundwater storage changes in both confined and unconfined aquifer systems using a global-scale high-resolution (5‧) groundwater model by deriving new estimates of the distribution and thickness of confining layers. Inclusion of confined aquifer systems (estimated 6-20% of the total aquifer area) improves estimates of timing and amplitude of groundwater head fluctuations and changes groundwater flow paths and groundwater-surface water interaction rates. Groundwater flow paths within confining layers are shorter than paths in the underlying aquifer, while flows within the confined aquifer can get disconnected from the local drainage system due to the low conductivity of the confining layer. Lateral groundwater flows between basins are significant in the model, especially for areas with (partially) confined aquifers were long flow paths crossing catchment boundaries are simulated, thereby supporting water budgets of neighboring catchments or aquifer systems. The developed two-layer transient groundwater model is used to identify hot-spots of groundwater depletion. Global groundwater depletion is estimated as 7013 km3 (137 km3y-1) over 1960-2010, which is consistent with estimates of previous studies.

  18. Remote instruction in groundwater hydrology

    Science.gov (United States)

    staff of the Interactive Remote Instructional System

    Wright State University (Dayton, Ohio) is preparing for its fourth cycle of the Interactive Remote Instructional System (IRIS) in groundwater hydrology beginning July 15, 1986. The Department of Geological Sciences proudly announces that the first two cycles recorded an impressive 83% completion ratio for registered participants. This completion rate is a significant departure from success rates traditionally recorded by courses of this nature; it is the result of 2 years of implementation and refinement and demonstrates the progressive orientation of the program. The third cycle has been underway since January. This comprehensive hydrogeology program was originally developed for the U.S. Department of Agriculture Soil Conservation Service to prepare their personnel for professional practice work. As a result of that cooperative effort, the IRIS program has evolved to meet the needs of participants by developing a curriculum that reflects current trends in the groundwater industry and has provided a unique educational approach that ensures maximum interaction between the instructional staff and participants.

  19. 40 CFR 265.91 - Ground-water monitoring system.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of: (1...

  20. Review of Groundwater Protection and Management in China

    Institute of Scientific and Technical Information of China (English)

    LIU Dan; ZHANG Ai-ping

    2008-01-01

    This review begins with an introduction of groundwater resources in China and their distribution characteristic, followed by an elaboration of the exploitation and utilization of groundwater and the negative environmental effects from groundwater overexploitation, and a description of the existing groundwater protection and management measures. At last, the existing problems in groundwater protection and management, with some suggestions, are presented.

  1. Groundwater surface mapping informs sources of catchment baseflow

    OpenAIRE

    J. F. Costelloe; T. J. Peterson; K. Halbert; A. W. Western; J. J. McDonnell

    2014-01-01

    Groundwater discharge is a major contributor to stream baseflow. Quantifying this flux is difficult, despite its considerable importance to water resource management and evaluation of the effects of groundwater extraction on streamflow. It is important to be able to differentiate between contributions to streamflow from regional groundwater discharge (more susceptible to groundwater extraction) compared to interflow processes (arguably less susceptible to groundwater ...

  2. Eielson Air Force Base operable unit 2 and other areas record of decision

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, R.E.; Smith, R.M.

    1994-10-01

    This decision document presents the selected remedial actions and no action decisions for Operable Unit 2 (OU2) at Eielson Air Force Base (AFB), Alaska, chosen in accordance with state and federal regulations. This document also presents the decision that no further action is required for 21 other source areas at Eielson AFB. This decision is based on the administrative record file for this site. OU2 addresses sites contaminated by leaks and spills of fuels. Soils contaminated with petroleum products occur at or near the source of contamination. Contaminated subsurface soil and groundwater occur in plumes on the top of a shallow groundwater table that fluctuates seasonally. These sites pose a risk to human health and the environment because of ingestion, inhalation, and dermal contact with contaminated groundwater. The purpose of this response is to prevent current or future exposure to the contaminated groundwater, to reduce further contaminant migration into the groundwater, and to remediate groundwater.

  3. Study of Seasonal Variation in Groundwater Quality of Sagar City (India by Principal Component Analysis

    Directory of Open Access Journals (Sweden)

    Hemant Pathak

    2011-01-01

    Full Text Available Groundwater is one of the major resources of the drinking water in Sagar city (India.. In this study 15 sampling station were selected for the investigations on 14 chemical parameters. The work was carried out during different months of the pre-monsoon, monsoon and post-monsoon seasons in June 2009 to June 2010. The multivariate statistics such as principal component and cluster analysis were applied to the datasets to investigate seasonal variations in groundwater quality. Principal axis factoring has been used to observe the mode of association of parameters and their interrelationships, for evaluating water quality. Average value of BOD, COD, ammonia and iron was high during entire study period. Elevated values of BOD and ammonia in monsoon, slightly more value of BOD in post-monsoon, BOD, ammonia and iron in pre-monsoon period reflected contribution on temporal effect on groundwater. Results of principal component analysis evinced that all the parameters equally and significantly contribute to groundwater quality variations. Factor 1 and factor 2 analysis revealed the DO value deteriorate due to organic load (BOD/Ammonia in different seasons. Hierarchical cluster analysis grouped 15 stations into four clusters in monsoon, five clusters in post-monsoon and five clusters in pre-monsoon with similar water quality features. Clustered group at monsoon, post-monsoon and pre-monsoon consisted one station exhibiting significant spatial variation in physicochemical composition. The anthropogenic nitrogenous species, as fallout from modernization activities. The study indicated that the groundwater sufficiently well oxygenated and nutrient-rich in study places.

  4. Groundwater subsidies and penalties to corn yield

    Science.gov (United States)

    Zipper, S. C.; Booth, E.; Loheide, S. P.

    2013-12-01

    Proper water management is critical to closing yield gaps (observed yield below potential yield) as global populations continue to expand. However, the impacts of shallow groundwater on crop production and surface processes are poorly understood. The presence of groundwater within or just below the root zone has the potential to cause (via oxygen stress in poorly drained soils) or eliminate (via water supply in dry regions) yield gaps. The additional water use by a plant in the presence of shallow groundwater, compared to free drainage conditions, is called the groundwater subsidy; the depth at which the groundwater subsidy is greatest is the optimal depth to groundwater (DTGW). In wet years or under very shallow water table conditions, the groundwater subsidy is likely to be negative due to increased oxygen stress, and can be thought of as a groundwater penalty. Understanding the spatial dynamics of groundwater subsidies/penalties and how they interact with weather is critical to making sustainable agricultural and land-use decisions under a range of potential climates. Here, we examine patterns of groundwater subsidies and penalties in two commercial cornfields in the Yahara River Watershed, an urbanizing agricultural watershed in south-central Wisconsin. Water table levels are generally rising in the region due to a long-term trend of increasing precipitation over the last several decades. Biophysical indicators tracked throughout both the 2012 and 2013 growing seasons show a strong response to variable groundwater levels on a field scale. Sections of the field with optimal DTGW exhibit consistently higher stomatal conductance rates, taller canopies and higher leaf area index, higher ET rates, and higher pollination success rates. Patterns in these biophysical lines of evidence allow us to pinpoint specific periods within the growing season that plants were experiencing either oxygen or water stress. Most importantly, groundwater subsidies and penalties are

  5. Situ treatment of contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    McNab, Jr., Walt W. (Concord, CA); Ruiz, Roberto (Tracy, CA); Pico, Tristan M. (Livermore, CA)

    2001-01-01

    A system for treating dissolved halogenated organic compounds in groundwater that relies upon electrolytically-generated hydrogen to chemically reduce the halogenated compounds in the presence of a suitable catalyst. A direct current is placed across at least a pair, or an array, of electrodes which are housed within groundwater wells so that hydrogen is generated at the cathode and oxygen at the anode. A pump is located within the well housing in which the cathode(s) is(are) located and draws in groundwater where it is hydrogenated via electrolysis, passes through a well-bore treatment unit, and then transported to the anode well(s) for reinjection into the ground. The well-bore treatment involves a permeable cylinder located in the well bore and containing a packed bed of catalyst material that facilitates the reductive dehalogenation of the halogenated organic compounds by hydrogen into environmentally benign species such as ethane and methane. Also, electro-osmatic transport of contaminants toward the cathode also contributes to contaminant mass removal. The only above ground equipment required are the transfer pipes and a direct circuit power supply for the electrodes. The electrode wells in an array may be used in pairs or one anode well may be used with a plurality of cathode wells. The DC current flow between electrode wells may be periodically reversed which controls the formation of mineral deposits in the alkaline cathode well-bore water, as well as to help rejuvenate the catalysis.

  6. Groundwater and climate change: mitigating the global groundwater crisis and adapting to climate change model

    Science.gov (United States)

    To better understand the effects of climate change on global groundwater resources, the United Nations Educational, Scientific, and Cultural Organization (UNESCO) International Hydrological Programme (IHP) initiated the GRAPHIC (Groundwater Resources Assessment under the Pressures of Humanity and Cl...

  7. Results of groundwater monitoring at Everest, Kansas, in April 2008.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M.; Environmental Science Division

    2008-11-05

    On September 7, 2005, the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) presented a Scoping Memo (Argonne 2005) for preliminary consideration by the Kansas Department of Health and Environment (KDHE), suggesting possible remedial options for the carbon tetrachloride contamination in groundwater at Everest, Kansas. The suggested approaches were discussed by representatives of the KDHE, the CCC/USDA, and Argonne at the KDHE office in Topeka on September 8-9, 2005, along with other technical and logistic issues related to the Everest site. In response to these discussions, the KDHE recommended (KDHE 2005) evaluation of several remedial processes, either alone or in combination, as part of a Corrective Action Study (CAS) for Everest. The primary remedial processes suggested by the KDHE were the following: Hydraulic control by groundwater extraction with aboveground treatment; Air sparging (AS) coupled with soil vapor extraction (SVE) in large-diameter boreholes (LDBs); and Phytoremediation. As a further outcome of the 2005 meeting and as a precursor to development of a possible CAS, the CCC/USDA completed the following supplemental investigations at Everest to address several specific technical concerns discussed with the KDHE: (1) Construction of interpretive cross sections at strategic locations selected by the KDHE along the main plume migration pathway, to depict the hydrogeologic characteristics affecting groundwater flow and contaminant movement (Argonne 2006a). (2) A field investigation in early 2006 (Argonne 2006b), as follows: (a) Installation and testing of a production well and associated observation points, at locations approved by the KDHE, to determine the response of the Everest aquifer to groundwater extraction near the Nigh property. (b) Groundwater sampling for the analysis of volatile organic compounds (VOCs) and the installation of additional permanent monitoring points at locations selected by the KDHE, to further

  8. Monitoring groundwater drought with GRACE data assimilation

    Science.gov (United States)

    Li, B.; Rodell, M.; Beaudoing, H. K.; Getirana, A.; Zaitchik, B. F.

    2015-12-01

    Groundwater drought is a distinct class of drought, not a sub-class of meteorological, agricultural and hydrological drought and has profound impacts on natural environments and societies. Due to a deficiency of in situ measurements, we developed a groundwater drought indicator using groundwater change estimates derived by assimilating GRACE derived terrestrial water storage (TWS) anomalies into the NASA Catchment land surface model. Data assimilation enables spatial and temporal downscaling of coarse GRACE TWS observations (monthly and ~150,000 km2 effective spatial resolution) and extrapolation to near-real time. In this talk, we will present our latest progress on using GRACE satellite data for groundwater drought monitoring in the U.S. and globally. Characteristics of this groundwater drought indicator will be discussed, including its relationship with other types of drought and how they are influenced by model physics and climate conditions. Results are evaluated using in situ groundwater observations.

  9. Quantification of Seepage in Groundwater Dependent Wetlands

    DEFF Research Database (Denmark)

    Johansen, Ole; Beven, Keith; Jensen, Jacob Birk

    2017-01-01

    Restoration and management of groundwater dependent wetlands require tools for quantifying the groundwater seepage process. A method for determining point estimates of the groundwater seepage based on water level observations is tested. The study is based on field data from a Danish rich fen....... Therefore secondly a much simpler mass balance approach is used with lumped descriptions of the most important hydrological processes controlling water level and groundwater inflow to the system. The water level dynamics are here described and bracketed nicely and a dynamic description of the seepage rate...... the dynamic description of groundwater seepage can be very useful in future studies of the links between seepage, soil water chemistry and vegetation in groundwater dependent terrestrial ecosystems....

  10. ARSENIC CONTAMINATION IN GROUNDWATER: A STATISTICAL MODELING

    Directory of Open Access Journals (Sweden)

    Palas Roy

    2013-01-01

    Full Text Available High arsenic in natural groundwater in most of the tubewells of the Purbasthali- Block II area of Burdwan district (W.B, India has recently been focused as a serious environmental concern. This paper is intending to illustrate the statistical modeling of the arsenic contaminated groundwater to identify the interrelation of that arsenic contain with other participating groundwater parameters so that the arsenic contamination level can easily be predicted by analyzing only such parameters. Multivariate data analysis was done with the collected groundwater samples from the 132 tubewells of this contaminated region shows that three variable parameters are significantly related with the arsenic. Based on these relationships, a multiple linear regression model has been developed that estimated the arsenic contamination by measuring such three predictor parameters of the groundwater variables in the contaminated aquifer. This model could also be a suggestive tool while designing the arsenic removal scheme for any affected groundwater.

  11. Water-carbon Links in a Tropical Forest: How Interbasin Groundwater Flow Affects Carbon Fluxes and Ecosystem Carbon Budgets

    Energy Technology Data Exchange (ETDEWEB)

    Genereux, David [NC State University; Osburn, Christopher [NC State University; Oberbauer, Steven [Florida International University; Oviedo Vargas, Diana [NC State University; Dierick, Diego [Florida International University

    2017-03-27

    This report covers the outcomes from a quantitative, interdisciplinary field investigation of how carbon fluxes and budgets in a lowland tropical rainforest are affected by the discharge of old regional groundwater into streams, springs, and wetlands in the forest. The work was carried out in a lowland rainforest of Costa Rica, at La Selva Biological Station. The research shows that discharge of regional groundwater high in dissolved carbon dioxide represents a significant input of carbon to the rainforest "from below", an input that is on average larger than the carbon input "from above" from the atmosphere. A stream receiving discharge of regional groundwater had greatly elevated emissions of carbon dioxide (but not methane) to the overlying air, and elevated downstream export of carbon from its watershed with stream flow. The emission of deep geological carbon dioxide from stream water elevates the carbon dioxide concentrations in air above the streams. Carbon-14 tracing revealed the presence of geological carbon in the leaves and stems of some riparian plants near streams that receive inputs of regional groundwater. Also, discharge of regional groundwater is responsible for input of dissolved organic matter with distinctive chemistry to rainforest streams and wetlands. The discharge of regional groundwater in lowland surface waters has a major impact on the carbon cycle in this and likely other tropical and non-tropical forests.

  12. Y-12 Plant Groundwater Protection Program Groundwater and Surface Water sampling and Analysis Plan for Calendar Year 2000

    Energy Technology Data Exchange (ETDEWEB)

    None

    1999-09-01

    This plan provides a description of the groundwater and surface water quality monitoring activities planned for calendar year (CY) 2000 at the U.S. Department of Energy (DOE) Y-12 Plant that will be managed by tie Y-12 Plant Groundwater Protection Program (GWPP). Groundwater and surface water monitoring during CY 2000 will be performed in three hydrogeologic regimes at the Y-12 Plant: the Bear Creek Hydrogeologic Regime (Bear Creek Regime), the Upper East Fork Poplar Creek Hydrogeologic Regime (East Fork Regime), and the Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime). The Bear Creek and East Fork regimes are located in Bear Creek Valley, and the Chestnut Ridge Regime is located south of the Y-12 Plant (Figure 1). Groundwater and surface water monitoring performed under the auspices of the Y-12 Plant GWPP during CY 2000 will comply with: Tennessee Department of Environment and Conservation regulations governing detection monitoring at nonhazardous Solid Waste Disposal Facilities (SWDF); and DOE Order 5400.1 surveillance monitoring and exit pathway/perimeter monitoring. Some of the data collected for these monitoring drivers also will be used to meet monitoring requirements of the Integrated Water Quality Program, which is managed by Bechtel Jacobs Company LLC. Data from five wells that are monitored for SWDF purposes in the Chestnut Ridge Regime will be used to comply with requirements specified in the Resource Conservation and Recovery Act post closure permit regarding corrective action monitoring. Modifications to the CY 2000 monitoring program may be necessary during implementation. Changes in regulatory or programmatic requirements may alter the analytes specified for selected monitoring wells, or wells could be added or removed from the planned monitoring network. All modifications to the monitoring program will be approved by the Y-12 Plant GWPP manager and documented as addenda to this sampling and analysis plan.

  13. Phytoremediation of 1,4-dioxane-containing recovered groundwater.

    Science.gov (United States)

    Ferro, Ari M; Kennedy, Jean; LaRue, James C

    2013-01-01

    The results of a pilot-scale phytoremediation study are reported in this paper. Small plots of trees established on a closed municipal waste landfill site were irrigated with recovered groundwater containing 1,4-dioxane (dioxane) and other volatile organic compounds (VOCs). The plots were managed to minimize the leaching of irrigation water, and leaching was quantified by the use of bromide tracer. Results indicated that the dioxane (2.5 microg/L) was effectively removed, probably via phytovolatilization, and that a full-scale phytoremediation system could be used. A system is now in place at the site in which the recovered groundwater can be treated using two different approaches. A physical treatment system (PTS) will be used during the winter months, and a 12 ha phytoremediation system (stands of coniferous trees) will be used during the growing season. The PTS removes VOCs using an air-stripper, and destroys dioxane using a photo-catalytic oxidation process. Treated water will be routed to the local sewer system. The phytoremediation system, located on the landfill, will be irrigated with effluent from the PTS air-stripper containing dioxane. Seasonal use of the phytoremediation system will reduce reliance on the photo-catalytic oxidation process that is extremely energy consumptive and expensive to operate.

  14. Groundwater flow modelling of periods with temperate climate conditions - Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Joyce, Steven; Simpson, Trevor; Hartley, Lee; Applegate, David; Hoek, Jaap; Jackson, Peter; Roberts, David; Swan, David (Serco Technical Consulting Services (United Kingdom)); Gylling, Bjoern; Marsic, Niko (Kemakta Konsult AB, Stockholm (Sweden)); Rhen, Ingvar (SWECO Environment AB, Falun (Sweden))

    2010-12-15

    As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. This report concerns the modelling of a repository at the Laxemar-Simpevarp site during temperate climate conditions as a comparison to corresponding modelling carried out for Forsmark /Joyce et al. 2010/. The collation and implementation of onsite hydrogeological and hydrogeochemical data from previous reports are used in the construction of a Hydrogeological base case (reference case conceptualisation) and then an examination of various areas of uncertainty within the current understanding by a series of model variants. The Hydrogeological base case models at three different scales, 'repository', 'site' and 'regional' make use of a discrete fracture network (DFN) and equivalent continuous porous medium (ECPM) models. The use of hydrogeological models allow for the investigation of the groundwater flow from a deep disposal facility to the biosphere and for the calculation of performance measures that will provide an input to the site performance assessment. The focus of the study described in this report has been to perform numerical simulations of the hydrogeological system from post-closure and throughout the temperate period up until the receding shoreline leaves the modelling domain at around 15,000 AD. Besides providing quantitative results for the immediate temperate period following post-closure, these results are also intended to give a qualitative indication of the evolution of the groundwater system during future temperate periods within an ongoing cycle of glacial/inter-glacial events

  15. Coastal Zone Hazards Related to Groundwater-Surface Water Interactions and Groundwater Flooding

    Science.gov (United States)

    Kontar, Y. A.; Ozorovich, Y. R.; Salokhiddinov, A. T.

    2009-12-01

    Worldwide, as many as half a million people have died in natural and man-made disasters since the turn of the 21st century (Wirtz, 2008). Further, natural and man-made hazards can lead to extreme financial losses (Elsner et al, 2009). Hazards, hydrological and geophysical risk analysis related to groundwater-surface water interactions and groundwater flooding have been to a large extent under-emphasized for coastal zone applications either due to economical limitations or underestimation of its significance. This is particularly true for tsunamis creating salt water intrusion to coastal aquifers, even though most tsunami hazard assessments have in the past relied on scenario or deterministic type models (Geist and Parsons, 2006), and to increasing mineralization of potable water because of intensive water diversions and also the abundance of highly toxic pollutants (mainly pesticides) in water, air and food, which contribute to the deterioration of the coastal population's health (Glantz, 2007). In the wake of pressing environmental and economic issues, it is of prime importance for the scientific community to shed light onto the great efforts by hydrologists and geophysicists to quantify conceptual uncertainties and to provide quality assurances of potential coastal zone hazard evaluation and prediction. This paper proposes consideration of two case studies which are important and significant for future development and essential for feasibility studies of hazards in the coastal zone. The territory of the Aral Sea Region in Central Asia is known as an ecological disaster coastal zone (Zavialov, 2005). It is now obvious that, in order to provide reasonable living conditions to the coastal zone population, it is first of all necessary to drastically improve the quality of the water dedicated to human needs. Due to their intensive pollution by industrial wastes and by drainage waters from irrigated fields, the Syr Darya and Amu Darya rivers can no longer be considered

  16. Compendium of ordinances for groundwater protection

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-01

    Groundwater is an extremely important resource in the Tennessee Valley. Nearly two-thirds of the Tennessee Valley's residents rely, at least in part, on groundwater supplies for drinking water. In rural areas, approximately ninety-five percent of residents rely on groundwater for domestic supplies. Population growth and economic development increase the volume and kinds of wastes requiring disposal which can lead to groundwater contamination. In addition to disposal which can lead to groundwater contamination. In addition to disposal problems associated with increases in conventional wastewater and solid waste, technological advancements in recent decades have resulted in new chemicals and increased usage in agriculture, industry, and the home. Unfortunately, there has not been comparable progress in identifying the potential long-term effects of these chemicals, in managing them to prevent contamination of groundwater, or in developing treatment technologies for removing them from water once contamination has occurred. The challenge facing residence of the Tennessee Valley is to manage growth and economic and technological development in ways that will avoid polluting the groundwater resource. Once groundwater has been contaminated, cleanup is almost always very costly and is sometimes impractical or technically infeasible. Therefore, prevention of contamination -- not remedial treatment--is the key to continued availability of usable groundwater. This document discusses regulations to aid in this prevention.

  17. Groundwater Level Predictions Using Artificial Neural Networks

    Institute of Scientific and Technical Information of China (English)

    毛晓敏; 尚松浩; 刘翔

    2002-01-01

    The prediction of groundwater level is important for the use and management of groundwater resources. In this paper, the artificial neural networks (ANN) were used to predict groundwater level in the Dawu Aquifer of Zibo in Eastern China. The first step was an auto-correlation analysis of the groundwater level which showed that the monthly groundwater level was time dependent. An auto-regression type ANN (ARANN) model and a regression-auto-regression type ANN (RARANN) model using back-propagation algorithm were then used to predict the groundwater level. Monthly data from June 1988 to May 1998 was used for the network training and testing. The results show that the RARANN model is more reliable than the ARANN model, especially in the testing period, which indicates that the RARANN model can describe the relationship between the groundwater fluctuation and main factors that currently influence the groundwater level. The results suggest that the model is suitable for predicting groundwater level fluctuations in this area for similar conditions in the future.

  18. The challenges facing sustainable and adaptive groundwater ...

    African Journals Online (AJOL)

    The challenges facing sustainable and adaptive groundwater management ... provide the capacity to assure effective and sustainable resource regulation and allocation. ... of alternative strategies needed to achieve sustainable management.

  19. Remedies proposed for China's groundwater problems

    Science.gov (United States)

    Loaiciga, Hugo A.

    Groundwater experts and hydrologists from China and 10 other nations recently gathered in Beijing to exchange state-of-the-art scientific and technological knowledge on groundwater hydrology, modeling, remediation, and management. The participants also reviewed groundwater environmental conditions in China, identified key problems, and made recommendations to help guide the nation's groundwater policy.The Regional Workshop on Ground Water Contamination, held from July 31 to August 4, 1995, was the fifth of a series of regional workshops sponsored by the Scientific Committee on Problems of the Environment of the United Nations Environmental Program. Earlier workshops were held in Thailand (1991), Costa Rica (1993), the Czech Republic (1994), and Australia (1994).

  20. Estimating Groundwater Development area in Jianan Plain using Standardized Groundwater Index

    Science.gov (United States)

    Yu, Chang Hsiang; Haw, Lee Cheng

    2017-04-01

    Taiwan has been facing severe water crises in recent years owing to the effects of extreme weather conditions. Changes in precipitation patterns have also made the drought phenomenon increasingly prominent, which has indirectly affected groundwater recharge. Hence, in the present study, long-term monitoring data were collected from the study area of the Jianan plain. The standardized groundwater index (SGI) and was then used to analyse the region's drought characteristics. To analyse the groundwater level by using SGI, making SGI180 groundwater level be the medium water crises, and SGI360 groundwater level be the extreme water crises. Through the different water crises signal in SGI180 and SGI360, we divide groundwater in Jianan plain into two sections. Thereby the water crises indicators establishing groundwater level standard line in Jianan Plain, then using the groundwater level standard line to find the study area where could be groundwater development area in Jianan plain. Taking into account relatively more water scarcity in dry season, so the study screen out another emergency backup groundwater development area, but the long-term groundwater development area is still as a priority development area. After finding suitable locations, groundwater modeling systems(GMS) software is used to simulate our sites to evaluate development volume. Finally, the result of study will help the government to grasp the water shortage situation immediately and solve the problem of water resources deployment.

  1. Using polymer mats to biodegrade atrazine in groundwater: laboratory column experiments

    Science.gov (United States)

    Patterson, B. M.; Franzmann, P. D.; Davis, G. B.; Elbers, J.; Zappia, L. R.

    2002-02-01

    Large-scale column experiments were undertaken to evaluate the potential of in situ polymer mats to deliver oxygen into groundwater to induce biodegradation of the pesticides atrazine, terbutryn and fenamiphos contaminating groundwater in Perth, Western Australia. The polymer mats, composed of woven silicone (dimethylsiloxane) tubes and purged with air, were installed in 2-m-long flow-through soil columns. The polymer mats proved efficient in delivering dissolved oxygen to anaerobic groundwater. Dissolved oxygen concentrations increased from biodegradation rates, suggesting that organic carbon was not limiting biodegradation. Atrazine degradation rates estimated in the column experiments were similar to rates determined in laboratory culture experiments, using pure cultures of atrazine-mineralising bacteria. No significant degradation of terbutryn or fenamiphos was observed under the experimental conditions within the time frames of the study. Results from these experiments indicate that remediation of atrazine in a contaminated aquifer may be achievable by delivery of oxygen using an in situ polymer mat system.

  2. Groundwater management for agriculture and nature: an economic analysis

    NARCIS (Netherlands)

    Hellegers, P.J.G.J.

    2001-01-01

    Key words: desiccation of nature, economics of water management, groundwater extraction, groundwater level management, ecohydrology, agriculture, policy instruments.

    As a result of declining groundwater levels, nature in the Netherlands is suffering

  3. Groundwater Management for Agriculture and Nature : an Economic Analysis

    NARCIS (Netherlands)

    Hellegers, P.

    2001-01-01

    Key words: desiccation of nature, economics of water management, groundwater extraction, groundwater level management, ecohydrology, agriculture, policy instruments.As a result of declining groundwater levels, nature in the Netherlands is suffering from desiccation. Since measures taken to raise gro

  4. The Present Situation and Countermeasures of Groundwater Contamination in Japan

    OpenAIRE

    Shindo, Shizuo; Tang, Changyuan

    1997-01-01

    [ABSTRACT] Since 1982, thousands of groundwater pollution cases have been found in Japan. In order to improve the groundwater quality, Japan has developed strategies for protection of groundwater. In this paper, authors try to explain the present of groundwater use, groundwater pollution and remediation methods in Japan. From the results shown in this paper, it can be found that groundwater pollution problem has become very serious in Japan. Even many efforts have been made to improve the sit...

  5. Evaluation of Groundwater Pollution Nitrogen Fertilizer Using Expert System

    OpenAIRE

    Ta-oun, Mongkon; Daud, Mohamed; Bardaie, Mohd Zohadie

    2017-01-01

    An expert system was used to correlate the availability of nitrogen fertilizer with the vulnerability of groundwater to pollution in Peninsula Malaysia to identify potential groundwater quality problems. The expert system could predict the groundwater pollution potential under several conditions of agricultural activities and exiting environments. Four categories of groundwater pollution potential were identified base on an N-fertilizer groundwater pollution potential index. A groundwater pol...

  6. Noble gas tracing of groundwater/coalbed methane interaction in the San Juan Basin, USA

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Z.; Ballentine, C.J.; Kipfer, R.; Schoell, M.; Thibodeaux, S. [ETH, Zurich (Switzerland). Inst. of Isotope Geology & Mineral Resources

    2005-12-01

    The San Juan Basin natural gas field, located in northwestern New Mexico and southwestern Colorado in the USA, is a case-type coalbed methane system. Groundwater is thought to play a key role in both biogenic methane generation and the CO{sub 2} sequestration potential of coalbed systems. We show here how noble gases can be used to construct a physical model that describes the interaction between the groundwater system and the produced gas. The results conclusively show that the volume of groundwater seen by coal does not play a role in determining the volume of methane produced by secondary biodegradation of these coalbeds. There is no requirement of continuous groundwater flow for renewing the microbes or nutrient components. Strong mass related isotopic fractionation of {sup 20}Ne/{sup 22}NE and {sup 38}Ar/{sup 36} isotopic ratios was also seen. This can be explained by a noble gas concentration gradient in the groundwater during gas production, which causes diffusive partial re-equilibration of the noble gas isotopes. It is important for the study of other systems in which extensive groundwater degassing may have occurred to recognize that severe isotopic fractionation of air-derived noble gases can occur when such concentration gradients are established during gas production. Excess air-derived Xe and Kr in our samples are shown to be related to the diluting coalbed methane and can only be accounted for if Xe and Kr are preferentially and volumetrically trapped within the coal matrix and released during biodegradation to form CH{sub 4}.

  7. Response of the microbial community to seasonal groundwater level fluctuations in petroleum hydrocarbon-contaminated groundwater.

    Science.gov (United States)

    Zhou, Ai-xia; Zhang, Yu-ling; Dong, Tian-zi; Lin, Xue-yu; Su, Xiao-si

    2015-07-01

    The effects of seasonal groundwater level fluctuations on the contamination characteristics of total petroleum hydrocarbons (TPH) in soils, groundwater, and the microbial community were investigated at a typical petrochemical site in northern China. The measurements of groundwater and soil at different depths showed that significant TPH residue was present in the soil in this study area, especially in the vicinity of the pollution source, where TPH concentrations were up to 2600 mg kg(-1). The TPH concentration in the groundwater fluctuated seasonally, and the maximum variation was 0.8 mg L(-1). The highest TPH concentrations were detected in the silty clay layer and lied in the groundwater level fluctuation zones. The groundwater could reach previously contaminated areas in the soil, leading to higher groundwater TPH concentrations as TPH leaches into the groundwater. The coincident variation of the electron acceptors and TPH concentration with groundwater-table fluctuations affected the microbial communities in groundwater. The microbial community structure was significantly different between the wet and dry seasons. The canonical correspondence analysis (CCA) results showed that in the wet season, TPH, NO3(-), Fe(2+), TMn, S(2-), and HCO3(-) were the major factors correlating the microbial community. A significant increase in abundance of operational taxonomic unit J1 (97% similar to Dechloromonas aromatica sp.) was also observed in wet season conditions, indicating an intense denitrifying activity in the wet season environment. In the dry season, due to weak groundwater level fluctuations and low temperature of groundwater, the microbial activity was weak. But iron and sulfate-reducing were also detected in dry season at this site. As a whole, groundwater-table fluctuations would affect the distribution, transport, and biodegradation of the contaminants. These results may be valuable for the control and remediation of soil and groundwater pollution at this site

  8. Analysis of the potential contamination risk of groundwater resources circulating in areas with anthropogenic activities

    Directory of Open Access Journals (Sweden)

    M. Spizzico

    2005-01-01

    Full Text Available The area investigated is located in the province of Brindisi (Italy. It is a generally flat area separated from the nearby carbonatic plateau of the Murgia by quite indistinct and high fault scarps. As regards the geological features, carbonatic basement rocks and post-cretaceous terrains made up of calabrian calcarenites and middle-upper Pleistocenic marine terraced deposits can be distinguished. In the examined area there are two different hydrogeological environments. The first is represented by deep groundwater, the main groundwater resource in Apulia. The second hydrogeological environment, now of lesser importance than the deep aquifer in terms of size and use, is made up of some small shallow groundwater systems situated in post-calabrian sands and located in the eastern area. During some sampling cycles carried out in the studied area, water was withdrawn from both the deep aquifer and from the shallow groundwater. For every sample, the necessary parameters were determined for the physical and chemical characterisation of two different hydrogeological environments. Moreover, some chemical parameters indicating anthropogenic activities were determined. Analysis of the aerial distribution of the measured parameters has shown some main areas subject to different conditions of contamination risk, in accordance with the hydrogeological and geological features of the investigated area. In the south-eastern part of the investigated area, the important action performed by the surface aquifer for protecting the deep groundwater from contamination of anthropogenic origin is clear. On the other hand, in the shallow groundwater, areas of nitrate and nitrite contamination have been identified, which result from the extensive use of fertilizers.

  9. Cryptic flows: using multiple tracers to relate dissolved oxygen to hyporheic and groundwater flowpaths in intermittent salmonid streams

    Science.gov (United States)

    Woelfle-Erskine, C. A.; Larsen, L.; Gomez-Velez, J. D.

    2016-12-01

    Intermittent streams provide important habitat for aquatic species, including endangered salmonid fishes, but during prolonged dry periods may become depleted in dissolved oxygen (DO). The rate of depletion and the consequent length of time a pool remains habitable depend on DO and carbon concentrations in groundwater and hyporheic flow, and within-pool metabolic rates. We performed repeat surveys, habitat characterization, and ecohydrologic sampling on two intermittent tributaries of Salmon Creek (Sonoma Co., CA) to elucidate controls on salmonid over-summer survival at the pool scale. Pools exhibited heterogeneity within and across stream reaches in salmonid recruitment and survival during the summer dry period. In classification tree analysis, high conductivity (>310 mS/cm) and low DO (concentration. To distinguish between surface, hyporheic, and groundwater contributions, we measured dissolved organic carbon (DOC) concentration and fluorescence excitation-emission matrices (EEMs), radon (222Rn), and stable isotopes (18O and D) in pools, hyporheic flow, and wells and springs in local aquifers. Radon concentrations in pools ranged from 1.5-2.3 Bq/l, 3-4 orders of magnitude higher than expected for water in equilibrium with air, suggesting substantial groundwater inflow. We developed a five-component PARAFAC model from the EEMs and used with the isotope data to perform an end-member mixing analysis to track water sources and flowpaths. These analyses suggested high separability among groundwaters from aquifers separated by faults and between groundwater and surface water, with groundwater of different age and flowpath length discharging to different pools. Pools with shallow groundwater or hyporheic flow sustained DO concentrations above the threshold for salmonid survival, with shallow groundwater unexpectedly acting as a source of DO to the stream. These inflows were further essential for inhibiting stagnation and promoting reaeration across the air

  10. Global Climate Responses to Anthropogenic Groundwater Exploitation

    Science.gov (United States)

    Zeng, Y.; Xie, Z.

    2015-12-01

    In this study, a groundwater exploitation scheme is incorporated into the earth system model, Community Earth System Model 1.2.0 (CESM1.2.0), which is called CESM1.2_GW, and the climatic responses to anthropogenic groundwater withdrawal are then investigated on global scale. The scheme models anthropogenic groundwater exploitation and consumption, which are then divided into agricultural irrigation, industrial use and domestic use. A group of 41-year ensemble groundwater exploitation simulations with six different initial conditions, and a group of ensemble control simulations without exploitation are conducted using the developed model CESM1.2_GW with water supplies and demands estimated. The results reveal that the groundwater exploitation and water consumption cause drying effects on soil moisture in deep layers and wetting effects in upper layers, along with a rapidly declining groundwater table in Central US, Haihe River Basin in China and Northern India and Pakistan where groundwater extraction are most severe in the world. The atmosphere also responds to anthropogenic groundwater exploitation. Cooling effects on lower troposphere appear in large areas of North China Plain and of Northern India and Pakistan. Increased precipitation occurs in Haihe River Basin due to increased evapotranspiration from irrigation. Decreased precipitation occurs in Northern India because water vapor here is taken away by monsoon anomalies induced by anthropogenic alteration of groundwater. The local reducing effects of anthropogenic groundwater exploitation on total terrestrial water storage evinces that water resource is unsustainable with the current high exploitation rate. Therefore, a balance between slow groundwater withdrawal and rapid human economic development must be achieved to maintain a sustainable water resource, especially in over-exploitation regions such as Central US, Northern China, India and Pakistan.

  11. Ecology and living conditions of groundwater fauna

    Energy Technology Data Exchange (ETDEWEB)

    Thulin, Barbara (Geo Innova AB (Sweden)); Hahn, Hans Juergen (Arbeitsgruppe Grundwasseroekologie, Univ. of Koblenz-Landau (Germany))

    2008-09-15

    This report presents the current state of ecological knowledge and applied research relating to groundwater. A conceptual picture is given of groundwater fauna occurrence in regard to Swedish environmental conditions. Interpretation features for groundwater fauna and applications are outlined. Groundwater is one of the largest and oldest limnic habitats populated by a rich and diverse fauna. Both very old species and species occurring naturally in brackish or salt water can be found in groundwater. Groundwater ecosystems are heterotrophic; the fauna depends on imports from the surface. Most species are meiofauna, 0.3-1 mm. The food chain of groundwater fauna is the same as for relatives in surface water and salt water. Smaller animals graze biofilms and detritus, larger animals act facutatively as predators. A difference is that stygobiotic fauna has become highly adapted to its living space and tolerates very long periods without food. Oxygen is a limiting factor, but groundwater fauna tolerates periods with low oxygen concentrations, even anoxic conditions. For longer periods of time a minimum oxygen requirement of 1 mg/l should be fulfilled. Geographic features such as Quaternary glaciation and very old Pliocene river systems are important for distribution patterns on a large spatial scale, but aquifer characteristics are important on a landscape scale. Area diversity is often comparable to surface water diversity. However, site diversity is low in groundwater. Site specific hydrological exchange on a geological facies level inside the aquifer, e.g. porous, fractured and karstic aquifers as well as the hyporheic zone, controls distribution patterns of groundwater fauna. For a better understanding of controlling factors indicator values are suggested. Different adequate sampling methods are available. They are representative for the aquifer, but a suitable number of monitoring wells is required. The existence of groundwater fauna in Sweden is considered as very

  12. Changes in quality of groundwater with seasonal fluctuations: an example from Ghor Sari area, southern Dead Sea coastal aquifers, Jordan

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The demand for water resources in the area south of the Dead Sea due to continued development, especially at the Arab Potash Company (APC) for production and domestic purposes necessitates that water quality in the area be monitored and evaluated based on the local geology and hydrogeology. The objective of this paper is to monitor seasonal fluctuations of groundwater and to determine how fluctuation in the water levels will affect the groundwater quality. Groundwater levels were found to be influenced by rainfall and pumping of water from the wells for domestic and industrial use. Twenty water samples were collected from different wells and analyzed for major chemical constituents both in pre- and post-seasons to determine the quality variation. Chemical constituents are significantly increased after post-season recharge. According to the overall assessment of the area, water quality was found to be useful for drinking, irrigation and industry.

  13. Daytime and nighttime groundwater contributions to soils with different surface conditions

    Science.gov (United States)

    Xing, Xuguang; Ma, Xiaoyi; Shi, Wenjuan

    2015-12-01

    Contributions of groundwater to the soil-water balance play an important role in areas with shallow water tables. The characteristics of daytime and nighttime water flux using non-weighing lysimeters were studied from June to September 2012 and 2013 in the extremely arid Xinjiang Uyghur Autonomous Region in northwestern China. The study consisted of nine treatments: three surface conditions, bare soil and cotton plants, each with water tables at depths of 1.0, 1.5, and 2.0 m; and plastic mulch with a water table at 1.5 m but with three percentages of open areas (POAs) in the plastic. The groundwater supply coefficient (SC) and the groundwater contribution (GC) generally varied with surface conditions. Both SC and GC decreased in the bare-soil and cotton treatments with increasing depth of the groundwater. Both SC and GC increased in the plastic-mulch treatment with increasing POA. Average nighttime GCs in the bare-soil treatments in July and August (the midsummer months) were 50.8-60.8 and 53.2-65.3 %, respectively, of the total daily contributions. Average nighttime GCs in the cotton treatments in July and August were 51.4-60.2 and 51.5-58.1 %, respectively, of the total daily contributions. The average GCs in June and September, however, were lower at night than during the daytime. Soil temperature may thus play a more important role than air temperature in the upflow of groundwater.

  14. Local warming of groundwaters caused by the urban heat island effect in Istanbul, Turkey

    Science.gov (United States)

    Yalcin, Tolga; Yetemen, Omer

    2009-07-01

    The urban heat island (UHI) is a result of urbanization, causing local microclimatologic changes such as increase in ambient temperature. Factors causing the UHI effect are anthropogenic energy release, energy absorption by concrete, tarmac structures and traffic, although the main factor is the replacement of vegetation with man-made structures. These factors cause heating of not only local air but also subsurface and groundwater. Observations of groundwater temperatures from the urban, southern part of Istanbul (Turkey) and the rural, northern part of Istanbul revealed that the urban groundwater temperatures were 3.5°C higher than the rural. Urbanization is a direct consequence of improvements in technology and modern life. However, this comes at the cost of an ever-increasing demand for energy. Exploitation of low-enthalpy geothermal energy is an attractive alternative to fossil fuel based energies. From the environmental point of view, clean and cheap energy is the most preferable, with heat pumps being the best choice for recovery purposes. Usage of elevated groundwater temperature in the heat pumps in urban areas increases the efficiency of the heat pump system and yields more thermal energy than that of rural groundwater. This system may be applicable to Istanbul.

  15. Considering groundwater use to improve the assessment of groundwater pumping for irrigation in North Africa

    Science.gov (United States)

    Massuel, Sylvain; Amichi, Farida; Ameur, Fatah; Calvez, Roger; Jenhaoui, Zakia; Bouarfa, Sami; Kuper, Marcel; Habaieb, Hamadi; Hartani, Tarik; Hammani, Ali

    2017-04-01

    Groundwater resources in semi-arid areas and especially in the Mediterranean face a growing demand for irrigated agriculture and, to a lesser extent, for domestic uses. Consequently, groundwater reserves are affected and water-table drops are widely observed. This leads to strong constraints on groundwater access for farmers, while managers worry about the future evolution of the water resources. A common problem for building proper groundwater management plans is the difficulty in assessing individual groundwater withdrawals at regional scale. Predicting future trends of these groundwater withdrawals is even more challenging. The basic question is how to assess the water budget variables and their evolution when they are deeply linked to human activities, themselves driven by countless factors (access to natural resources, public policies, market, etc.). This study provides some possible answers by focusing on the assessment of groundwater withdrawals for irrigated agriculture at three sites in North Africa (Morocco, Tunisia and Algeria). Efforts were made to understand the different features that influence irrigation practices, and an adaptive user-oriented methodology was used to monitor groundwater withdrawals. For each site, different key factors affecting the regional groundwater abstraction and its past evolution were identified by involving farmers' knowledge. Factors such as farmer access to land and groundwater or development of public infrastructures (electrical distribution network) are crucial to decode the results of well inventories and assess the regional groundwater abstraction and its future trend. This leads one to look with caution at the number of wells cited in the literature, which could be oversimplified.

  16. Considering groundwater use to improve the assessment of groundwater pumping for irrigation in North Africa

    Science.gov (United States)

    Massuel, Sylvain; Amichi, Farida; Ameur, Fatah; Calvez, Roger; Jenhaoui, Zakia; Bouarfa, Sami; Kuper, Marcel; Habaieb, Hamadi; Hartani, Tarik; Hammani, Ali

    2017-09-01

    Groundwater resources in semi-arid areas and especially in the Mediterranean face a growing demand for irrigated agriculture and, to a lesser extent, for domestic uses. Consequently, groundwater reserves are affected and water-table drops are widely observed. This leads to strong constraints on groundwater access for farmers, while managers worry about the future evolution of the water resources. A common problem for building proper groundwater management plans is the difficulty in assessing individual groundwater withdrawals at regional scale. Predicting future trends of these groundwater withdrawals is even more challenging. The basic question is how to assess the water budget variables and their evolution when they are deeply linked to human activities, themselves driven by countless factors (access to natural resources, public policies, market, etc.). This study provides some possible answers by focusing on the assessment of groundwater withdrawals for irrigated agriculture at three sites in North Africa (Morocco, Tunisia and Algeria). Efforts were made to understand the different features that influence irrigation practices, and an adaptive user-oriented methodology was used to monitor groundwater withdrawals. For each site, different key factors affecting the regional groundwater abstraction and its past evolution were identified by involving farmers' knowledge. Factors such as farmer access to land and groundwater or development of public infrastructures (electrical distribution network) are crucial to decode the results of well inventories and assess the regional groundwater abstraction and its future trend. This leads one to look with caution at the number of wells cited in the literature, which could be oversimplified.

  17. Geochemical and statistical evaluation of groundwater in Imphal and Thoubal district of Manipur, India

    Science.gov (United States)

    Oinam, Jayalakshmi Devi; Ramanathan, AL.; Singh, Gurmeet

    2012-04-01

    In order to identify the hydrogeochemical process controlling the quality of groundwater, an extensive study was carried out in Imphal and Thoubal district of Manipur, India. The objectives of the studies were to delineate the spatial and temporal variability in groundwater quality and understand its suitability for human uses. In the study area groundwater samples from 45 location have been collected during the pre-monsoon, monsoon and post-monsoon seasons and analyzed for the major ions such as Ca2+, Mg2+, Na+, K+, HCO3-, Cl-, SO42-, NO3-, PO43-, F-, Fe and silica. The water quality of both districts was good for domestic and agricultural uses except for few samples. These saline samples were localized and were due to the inherent lithology of the study area. Three major hydrochemical facies (Ca-HCO3 type, mixed Ca-Na-HCO3 and Ca-Mg-Cl types in Imphal district and Ca-HCO3, mixed Ca-Mg-Cl and Ca-Cl type in Thoubal district) were identified. The mineral stability diagrams indicated that the groundwater is in equilibrium with kaolinite and Ca-montmorillonite whereas Gibbs plot showed that the chemical composition of ground water in both districts is controlled by the natural weathering processes irrespective of seasons. Among the chemical weathering processes, silicate weathering was dominant. The results were supported by Wilcox plot and USSL diagrams. The study reflected the overall suitability of groundwater for anthropogenic use.

  18. Groundwater iron assessment and consumption by women in rural northwestern Bangladesh.

    Science.gov (United States)

    Merrill, Rebecca D; Shamim, Abu A; Ali, Hasmot; Jahan, Nusrat; Labrique, Alain B; Christian, Parul; West, Keith P

    2012-02-01

    In Bangladesh, approximately 97 % of the rural population uses groundwater as a drinking source. In many areas of the country this water is known to have elevated levels of iron. The contribution to iron intake that this exposure provides, and the impact on health, are unknown. In the pre- and post-monsoon seasons of 2008, we measured iron content of household tube well water, explored local water collection methods, and estimated iron intake through consumption of groundwater for 276 women of reproductive age in a rural setting in northwestern Bangladesh. Groundwater samples were analyzed for total iron (mg/L), arsenic (category of µg/L), pH, temperature (°C), and oxidation-reduction potential (Eh). Participants drank [mean (SD); 2.7 (0.8) L] of water per day, all of which was collected from domestic tube wells. Total iron concentration in groundwater was high, [median (IQR) 16.3 (6.9, 28.2) mg/L], and variable throughout the area. Using this value, estimated daily iron intake [median (IQR)] was 41.1 (16.0, 71.0) mg from drinking water alone. The amount of water consumed was unrelated to its iron concentration (r = - 0.06; p = 0.33) despite potentially unpleasant organoleptic qualities of high iron content in water. Groundwater contributes substantially to daily iron intake of rural Bangladeshi women and currently represents an under-assessed potential source of dietary iron.

  19. Regulating groundwater use in developing countries

    DEFF Research Database (Denmark)

    Hansen, Lars Gårn; Jensen, Frank; Amundsen, Eirik S

    2014-01-01

    Worldwide groundwater is a common-pool resource that is potentially subject to the tragedy of the commons if water extraction is not adequately regulated. In developing countries the regulatory infrastructure is often too weak to allow detailed monitoring of individual groundwater extraction. For...

  20. Groundwater use on southern Idaho dairies

    Science.gov (United States)

    Dairy production has expanded in irrigated areas of the western and southwestern US, potentially competing for limited water supplies. Groundwater withdrawal was measured for two years on six dairy farms with 660 to 6400 milk cows in southern Idaho. Groundwater withdrawal was calculated on an equiva...

  1. Applied groundwater modeling, 2nd Edition

    Science.gov (United States)

    Anderson, Mary P.; Woessner, William W.; Hunt, Randall J.

    2015-01-01

    This second edition is extensively revised throughout with expanded discussion of modeling fundamentals and coverage of advances in model calibration and uncertainty analysis that are revolutionizing the science of groundwater modeling. The text is intended for undergraduate and graduate level courses in applied groundwater modeling and as a comprehensive reference for environmental consultants and scientists/engineers in industry and governmental agencies.

  2. Propagation of drought through groundwater systems

    NARCIS (Netherlands)

    Peters, E.

    2003-01-01

    Index words: drought, groundwater, simulation, synthetic data, extreme events

    The transformation of droughts as a result of the propagation through groundwater systems is examined by comparing droughts in time

  3. Propagation of drought through groundwater systems

    NARCIS (Netherlands)

    Peters, E.

    2003-01-01

    Index words: drought, groundwater, simulation, synthetic data, extreme events

    The transformation of droughts as a result of the propagation through groundwater systems is examined by comparing droughts in time se

  4. Groundwater contamination and pollution in micronesia

    Science.gov (United States)

    Detay, M.; Alessandrello, E.; Come, P.; Groom, I.

    1989-12-01

    This paper is an overview of groundwater contamination and pollution in th e main islands of the Federated States of Micronesia, the Republic of the Marshall Islands and the Republic of Belau (Palau). A strategy for the comprehensive protection of groundwater resources in the Trust Territory of the Pacific Islands is proposed.

  5. Groundwater links between Kenyan Rift Valley lakes

    OpenAIRE

    Becht, Robert; Mwango, Fred; Muno, Fred Amstrong

    2006-01-01

    The series of lakes in the bottom of the Kenyan Rift valley are fed by rivers and springs. Based on the water balance, the relative positions determining the regional groundwater flow systems and the analysis of natural isotopes it can be shown that groundwater flows from lake Naivasha to lake Magadi, Elementeita, Nakuru and Bogoria.

  6. STRATEGIC ISSUES GROUNDWATER EXTRACTION MANAGEMENT IN RUSSIA

    Directory of Open Access Journals (Sweden)

    Ekaterina I. Golovina

    2017-05-01

    Full Text Available Water is a key component of our environment; it is a renewable, limited and vulnerable natural resource, which provides economic, social, and environmental well-being of the population. The most promising source of drinking water supply is groundwater usage. Drinking and industrial groundwater is one of the most important components of the groundwater mineral resource base in the Russian Federation. Modern system of groundwater extraction management and state regulation is currently imperfect and has definite disadvantages, among them - lack of control over natural resources by the state, an old system of tax rates for the use of groundwater, commercialization stage of licensing, the budget deficit, which is passed on other spheres of the national economy. This article provides general information about the state of groundwater production and supply in Russia, negative trends of groundwater usage, some actions for the improvement in the system of groundwater’s fund management are suggested. The most important amendments of the law “About mineral resources” are overviewed, effects of these changes are revealed and recommendations for future groundwater extraction regulation are given.

  7. Groundwater Pollution from Underground Coal Gasification

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In situ coal gasification poses a potential environmental risk to groundwater pollution although it depends mainly on local hydrogeological conditions.In our investigation, the possible processes of groundwater pollution originating from underground coal gasification (UCG) were analyzed.Typical pollutants were identified and pollution control measures are proposed.Groundwater pollution is caused by the diffusion and penetration of contaminants generated by underground gasification processes towards surrounding strata and the possible leaching of underground residue by natural groundwater flow after gasification.Typical organic pollutants include phenols, benzene, minor components such as PAHs and heterocyclics.Inorganic pollutants involve cations and anions.The natural groundwater flow after gasification through the seam is attributable to the migration of contaminants, which can be predicted by mathematical modeling.The extent and concentration of the groundwater pollution plume depend primarily on groundwater flow velocity, the degree of dispersion and the adsorption and reactions of the various contaminants.The adsorption function of coal and surrounding strata make a big contribution to the decrease of the contaminants over time and with the distance from the burn cavity.Possible pollution control measures regarding UCG include identifying a permanently, unsuitable zone, setting a hydraulic barrier and pumping contaminated water out for surface disposal.Mitigation measures during gasification processes and groundwater remediation after gasification are also proposed.

  8. 583 GROUNDWATER QUALITY ASSESSMENT AND MONITORING ...

    African Journals Online (AJOL)

    Osondu

    2012-10-30

    Oct 30, 2012 ... monitor and assess groundwater quality. Key words: ... improved yield/production and discharge of waste from ... Thus, the groundwater quality monitoring and .... D/Line. 28.51. 6.76. 49.42. 65.6. 23. ND. 60.24. 1.58. 10.361.

  9. Trend Analyses of Nitrate in Danish Groundwater

    DEFF Research Database (Denmark)

    Hansen, B.; Thorling, L.; Dalgaard, Tommy;

    2012-01-01

    This presentation assesses the long-term development in the oxic groundwater nitrate concentration and nitrogen (N) loss due to intensive farming in Denmark. Firstly, up to 20-year time-series from the national groundwater monitoring network enable a statistically systematic analysis of distribut......This presentation assesses the long-term development in the oxic groundwater nitrate concentration and nitrogen (N) loss due to intensive farming in Denmark. Firstly, up to 20-year time-series from the national groundwater monitoring network enable a statistically systematic analysis...... of distribution, trends and trend reversals in the groundwater nitrate concentration. Secondly, knowledge about the N surplus in Danish agriculture since 1950 is used as an indicator of the potential loss of N. Thirdly, groundwater recharge CFC (Chlorofluorocarbon) age determination allows linking of the first...... two dataset. The development in the nitrate concentration of oxic groundwater clearly mirrors the development in the national agricultural N surplus, and a corresponding trend reversal is found in groundwater. Regulation and technical improvements in the intensive farming in Denmark have succeeded...

  10. Improving fresh groundwater supply - problems and solutions

    NARCIS (Netherlands)

    Oude Essink, Gualbert

    2001-01-01

    Many coastal regions in the world experience an intensive salt water intrusion in aquifers due to natural and anthropogenic causes. The salinisation of these groundwater systems can lead to a severe deterioration of the quality of existing fresh groundwater resources. In this paper, the

  11. Procedures for ground-water investigations

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water monitoring procedures are developed and used in accordance with the PNL Quality Assurance Program.

  12. Groundwater residence times in Shenandoah National Park, Blue Ridge Mountains, Virginia, USA: A multi-tracer approach

    Science.gov (United States)

    Plummer, L.N.; Busenberg, E.; Böhlke, J.K.; Nelms, D.L.; Michel, R.L.; Schlosser, P.

    2001-01-01

    Chemical and isotopic properties of water discharging from springs and wells in Shenandoah National Park (SNP), near the crest of the Blue Ridge Mountains, VA, USA were monitored to obtain information on groundwater residence times. Investigated time scales included seasonal (wet season, April, 1996; dry season, August-September, 1997), monthly (March through September, 1999) and hourly (30-min interval recording of specific conductance and temperature, March, 1999 through February, 2000). Multiple environmental tracers, including tritium/helium-3 (3H/3He), chlorofluorocarbons (CFCs), sulfur hexafluoride (SF6), sulfur-35 (35S), and stable isotopes (??18O and ??2H) of water, were used to estimate the residence times of shallow groundwater discharging from 34 springs and 15 wells. The most reliable ages of water from springs appear to be based on SF6 and 3H/3He, with most ages in the range of 0-3 years. This range is consistent with apparent ages estimated from concentrations of CFCs; however, CFC-based ages have large uncertainties owing to the post-1995 leveling-off of the CFC atmospheric growth curves. Somewhat higher apparent ages are indicated by 35S (> 1.5 years) and seasonal variation of ??18O (mean residence time of 5 years) for spring discharge. The higher ages indicated by the 35S and ??18O data reflect travel times through the unsaturated zone and, in the case of 35S, possible sorption and exchange of S with soils or biomass. In springs sampled in April, 1996, apparent ages derived from the 3H/3He data (median age of 0.2 years) are lower than those obtained from SF6 (median age of 4.3 years), and in contrast to median ages from 3H/3He (0.3 years) and SF6 (0.7 years) obtained during the late summer dry season of 1997. Monthly samples from 1999 at four springs in SNP had SF6 apparent ages of only 1.2 to 2.5 ?? 0.8 years, and were consistent with the 1997 SF6 data. Water from springs has low excess air (0-1 cm3 kg-1) and N2-Ar temperatures that vary

  13. Global-scale modeling of groundwater recharge

    Science.gov (United States)

    Döll, P.; Fiedler, K.

    2008-05-01

    Long-term average groundwater recharge, which is equivalent to renewable groundwater resources, is the major limiting factor for the sustainable use of groundwater. Compared to surface water resources, groundwater resources are more protected from pollution, and their use is less restricted by seasonal and inter-annual flow variations. To support water management in a globalized world, it is necessary to estimate groundwater recharge at the global scale. Here, we present a best estimate of global-scale long-term average diffuse groundwater recharge (i.e. renewable groundwater resources) that has been calculated by the most recent version of the WaterGAP Global Hydrology Model WGHM (spatial resolution of 0.5° by 0.5°, daily time steps). The estimate was obtained using two state-of-the-art global data sets of gridded observed precipitation that we corrected for measurement errors, which also allowed to quantify the uncertainty due to these equally uncertain data sets. The standard WGHM groundwater recharge algorithm was modified for semi-arid and arid regions, based on independent estimates of diffuse groundwater recharge, which lead to an unbiased estimation of groundwater recharge in these regions. WGHM was tuned against observed long-term average river discharge at 1235 gauging stations by adjusting, individually for each basin, the partitioning of precipitation into evapotranspiration and total runoff. We estimate that global groundwater recharge was 12 666 km3/yr for the climate normal 1961-1990, i.e. 32% of total renewable water resources. In semi-arid and arid regions, mountainous regions, permafrost regions and in the Asian Monsoon region, groundwater recharge accounts for a lower fraction of total runoff, which makes these regions particularly vulnerable to seasonal and inter-annual precipitation variability and water pollution. Average per-capita renewable groundwater resources of countries vary between 8 m3/(capita yr) for Egypt to more than 1 million m3

  14. A method of groundwater quality assessment based on fuzzy network-CANFIS and geographic information system (GIS)

    Science.gov (United States)

    Gholami, V.; Khaleghi, M. R.; Sebghati, M.

    2016-12-01

    The process of water quality testing is money/time-consuming, quite important and difficult stage for routine measurements. Therefore, use of models has become commonplace in simulating water quality. In this study, the coactive neuro-fuzzy inference system (CANFIS) was used to simulate groundwater quality. Further, geographic information system (GIS) was used as the pre-processor and post-processor tool to demonstrate spatial variation of groundwater quality. All important factors were quantified and groundwater quality index (GWQI) was developed. The proposed model was trained and validated by taking a case study of Mazandaran Plain located in northern part of Iran. The factors affecting groundwater quality were the input variables for the simulation, whereas GWQI index was the output. The developed model was validated to simulate groundwater quality. Network validation was performed via comparison between the estimated and actual GWQI values. In GIS, the study area was separated to raster format in the pixel dimensions of 1 km and also by incorporation of input data layers of the Fuzzy Network-CANFIS model; the geo-referenced layers of the effective factors in groundwater quality were earned. Therefore, numeric values of each pixel with geographical coordinates were entered to the Fuzzy Network-CANFIS model and thus simulation of groundwater quality was accessed in the study area. Finally, the simulated GWQI indices using the Fuzzy Network-CANFIS model were entered into GIS, and hence groundwater quality map (raster layer) based on the results of the network simulation was earned. The study's results confirm the high efficiency of incorporation of neuro-fuzzy techniques and GIS. It is also worth noting that the general quality of the groundwater in the most studied plain is fairly low.

  15. Impacts of an ethanol-blended fuel release on groundwater and fate of produced methane: Simulation of field observations

    Science.gov (United States)

    In a field experiment at Vandenberg Air Force Base (VAFB) designed to mimic the impact of a small-volume release of E10, two plumes were created by injecting extracted groundwater spiked with benzene, toluene, and o-xylene, abbreviated BToX (No-Ethanol Lane) and BToX plus ethanol...

  16. Impacts of an ethanol-blended fuel release on groundwater and fate of produced methane: Simulation of field observations

    Science.gov (United States)

    In a field experiment at Vandenberg Air Force Base (VAFB) designed to mimic the impact of a small-volume release of E10, two plumes were created by injecting extracted groundwater spiked with benzene, toluene, and o-xylene, abbreviated BToX (No-Ethanol Lane) and BToX plus ethanol...

  17. Patterns in groundwater chemistry resulting from groundwater flow

    Science.gov (United States)

    Stuyfzand, Pieter J.

    Groundwater flow influences hydrochemical patterns because flow reduces mixing by diffusion, carries the chemical imprints of biological and anthropogenic changes in the recharge area, and leaches the aquifer system. Global patterns are mainly dictated by differences in the flux of meteoric water passing through the subsoil. Within individual hydrosomes (water bodies with a specific origin), the following prograde evolution lines (facies sequence) normally develop in the direction of groundwater flow: from strong to no fluctuations in water quality, from polluted to unpolluted, from acidic to basic, from oxic to anoxic-methanogenic, from no to significant base exchange, and from fresh to brackish. This is demonstrated for fresh coastal-dune groundwater in the Netherlands. In this hydrosome, the leaching of calcium carbonate as much as 15m and of adsorbed marine cations (Na+, K+, and Mg2+) as much as 2500m in the flow direction is shown to correspond with about 5000yr of flushing since the beach barrier with dunes developed. Recharge focus areas in the dunes are evidenced by groundwater displaying a lower prograde quality evolution than the surrounding dune groundwater. Artificially recharged Rhine River water in the dunes provides distinct hydrochemical patterns, which display groundwater flow, mixing, and groundwater ages. Résumé Les écoulements souterrains influencent les différents types hydrochimiques, parce que l'écoulement réduit le mélange par diffusion, porte les marques chimiques de changements biologiques et anthropiques dans la zone d'alimentation et lessive le système aquifère. Ces types dans leur ensemble sont surtout déterminés par des différences dans le flux d'eau météorique traversant le sous-sol. Dans les "hydrosomes" (masses d'eau d'origine déterminée), les lignes marquant une évolution prograde (séquence de faciès) se développent normalement dans la direction de l'écoulement souterrain : depuis des fluctuations fortes de la

  18. Geomorphic aspects of groundwater flow

    Science.gov (United States)

    LaFleur, Robert G.

    The many roles that groundwater plays in landscape evolution are becoming more widely appreciated. In this overview, three major categories of groundwater processes and resulting landforms are considered: (1) Dissolution creates various karst geometries, mainly in carbonate rocks, in response to conditions of recharge, geologic setting, lithology, and groundwater circulation. Denudation and cave formation rates can be estimated from kinetic and hydraulic parameters. (2) Groundwater weathering generates regoliths of residual alteration products at weathering fronts, and subsequent exhumation exposes corestones, flared slopes, balanced rocks, domed inselbergs, and etchplains of regional importance. Groundwater relocation of dissolved salts creates duricrusts of various compositions, which become landforms. (3) Soil and rock erosion by groundwater processes include piping, seepage erosion, and sapping, important agents in slope retreat and headward gully migration. Thresholds and limits are important in many chemical and mechanical groundwater actions. A quantitative, morphometric approach to groundwater landforms and processes is exemplified by selected studies in carbonate and clastic terrains of ancient and recent origins. Résumé Les rôles variés joués par les eaux souterraines dans l'évolution des paysages deviennent nettement mieux connus. La revue faite ici prend en considération trois grandes catégories de processus liés aux eaux souterraines et les formes associées: (1) La dissolution crée des formes karstiques variées, surtout dans les roches carbonatées, en fonction des conditions d'alimentation, du cadre géologique, de la lithologie et de la circulation des eaux souterraines. Les taux d'érosion et de formation des grottes peuvent être estimés à partir de paramètres cinétiques et hydrauliques. (2) L'érosion par les eaux souterraines donne naissance à des régolites, résidus d'altération sur des fronts d'altération, et l'exhumation r

  19. Parameter analysis for feasibility evaluation of shallow groundwater cooling of power plants

    Science.gov (United States)

    Dirix, Katrijn; Harcouët-Menou, Virginie; Van Bael, Johan; Laenen, Ben

    2017-04-01

    This paper presents the first results of a finite difference-based numerical model, aiming to evaluate the potential of a new cooling concept that is based on the use of closed loop groundwater cooling integrated in a binary cycle. The new concept includes the seasonal combination of air cooling and shallow groundwater cooling and is part of the H2020 MATChING project. The proposed cooling system under investigation will be compared with dry type cooler condenser (e.g. air cooled condenser systems) and aims to reduce overall water withdrawal without compromising the energy efficiency of the system. The pilot site for this evaluation is the geothermal Balmatt site in Mol-Dessel, Belgium. When operating at its full potential, this site could produce up to 27 MW of heat. To (partly) cool this heat, water from the permeable Miocene 'Diest formation' could be used in a closed loop, i.e. without consuming water. This aquifer is located at a depth of 35 to 151 m bgl, consists of glauconitic coarse sands and has an average permeability of 10 m/day. The water has a temperature of ca. 12°C. In the design under evaluation, this water will be heated up to a maximum of 22°C after passing through the condenser. During summer months, the water will be injected directly back into the aquifer, while in winter, additional cooling will be realised using an air cooler before injecting the water (at ca. 6 °C). By adding this extra cooling step, the lifetime of the system will increase significantly. To cool the large amount of rejected heat, over 2000 m3/h of water needs to be extracted from the aquifer, requiring the installation of several doublet systems. The feasibility of such an installation depends on several interdependent factors, such as temperature, pressure, well distance, distance between the doublets, permeability and natural flow conditions. Since no exact values of most of these factors are available, a large uncertainty exists for feasibility predictions. To assess

  20. Radon as a natural geochemical tracer for study of groundwater discharge into lakes

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Axel

    2008-06-27

    In the presented work the suitability of the naturally occurring radioactive noble gas isotope radon-222 for qualitative and quantitative description of groundwater discharge into lakes was studied. Basis of these investigations was the development of two innovative techniques for the on-site determination of radon in water. In the ex-situ radon measurement procedure, water from the source concerned is taken up in an exchange cell used for this purpose. Inside this cell, the radon dissolved in water is transferred via diffusion into a closed counter-flow of air and subsequently detected by a radon-in-air monitor. Where the in-situ radon determination is concerned, a module composed of a semipermeable membrane is introduced into a water column. Subsequently, the radon dissolved in the water body diffuses through the membrane into the corresponding air flow, by means of which it is transferred into a radon-in-air monitor and is detected. Combination of the developed mobile radon extraction techniques with a suitable and portable radon monitor allow the detection of radon-222 with sufficient accuracy (smaller 20 %) in groundwater as well as in surface waters, i.e., within a broad range of concentrations. Radon-222 was subsequently used to characterize groundwater discharge into a meromictic and a dimictic lake, i.e. two types of lake basically distinct from each other with respect to their water circulation properties were investigated. The use of the noble gas isotope radon-222 as a geochemical tracer makes the application of on-site detection techniques possible and that this in turn permits a rapid, reliable, and cost-effective assessment of groundwater discharge rates into lake water bodies.

  1. Groundwater-abstraction induced land subsidence and groundwater regulation in the North China Plain

    Science.gov (United States)

    Guo, H.; Wang, L.; Cheng, G.; Zhang, Z.

    2015-11-01

    Land subsidence can be induced when various factors such as geological, and hydrogeological conditions and intensive groundwater abstraction combine. The development and utilization of groundwater in the North China Plain (NCP) bring great benefits, and at the same time have led to a series of environmental and geological problems accompanying groundwater-level declines and land subsidence. Subsidence occurs commonly in the NCP and analyses show that multi-layer aquifer systems with deep confined aquifers and thick compressible clay layers are the key geological and hydrogeological conditions responsible for its development in this region. Groundwater overdraft results in aquifer-system compaction, resulting in subsidence. A calibrated, transient groundwater-flow numerical model of the Beijing plain portion of the NCP was developed using MODFLOW. According to available water supply and demand in Beijing plain, several groundwater regulation scenarios were designed. These different regulation scenarios were simulated with the groundwater model, and assessed using a multi-criteria fuzzy pattern recognition model. This approach is proven to be very useful for scientific analysis of sustainable development and utilization of groundwater resources. The evaluation results show that sustainable development of groundwater resources may be achieved in Beijing plain when various measures such as control of groundwater abstraction and increase of artificial recharge combine favourably.

  2. Application of hydrogeology and groundwater-age estimates to assess the travel time of groundwater at the site of a landfill to the Mahomet Aquifer, near Clinton, Illinois

    Science.gov (United States)

    Kay, Robert T.; Buszka, Paul M.

    2016-03-02

    sampled by this study. That result indicated that nearly all groundwater sampled from well G53S entered the aquifer as recharge before 1953. Tritium was detected in a trace concentration in one sample from a second monitoring well open to the upper part of the Radnor Till Member (well G07S; 0.11 ± 0.09 tritium units), and not detected in samples collected from two monitoring wells open to a sand deposit in the lower part of the Radnor Till Member, from two samples collected from two monitoring wells open to the Organic Soil unit, and in two samples collected from a production well screened in the middle of the Mahomet aquifer (a groundwater sample and a sequential replicate sample). The lack of tritium in five of the six groundwater samples collected from the shallow permeable units beneath CLU#3 site and the two samples from the one Mahomet aquifer well indicates an absence of post-1952 recharge. Groundwater-flow paths that could contribute post-1952 recharge to the lower part of the Radnor Till Member, the Organic Soil unit, or the Mahomet aquifer at the CLU#3 are not indicated by these data.Hypothetical two-part mixtures of tritium-dead, pre-1953 recharge water and decay-corrected tritium concentrations in post-1952 recharge were computed and compared with tritium analyses in groundwater sampled from monitoring wells at the CLU#3 site to evaluate whether tritium concentrations in groundwater could be represented by mixtures involving some post-1952 recharge. Results from the hypothetical two-part mixtures indicate that groundwater from monitoring well (G53S) was predominantly composed of pre-1953 recharge and that if present, younger, post-1955 recharge, contributed less than 2.5 percent to that sample. The hypothetical two-part mixing results also indicated that very small amounts of post-1952 recharge composing less than about 2.5 percent of the sample volume could not be distinguished in groundwater samples with tritium concentrations less than about 0.15 TU

  3. Geologic and hydrologic data for the municipal solid waste landfill facility, U.S. Army Air Defense Artillery Center and Fort Bliss, El Paso County, Texas

    Science.gov (United States)

    Abeyta, Cynthia G.; Frenzel, P.F.

    1999-01-01

    Geologic and hydrologic data for the Municipal Solid Waste Landfill Facility on the U.S. Army Air Defense Artillery Center and Fort Bliss in El Paso County, Texas, were collected by the U.S. Geological Survey in cooperation with the U.S. Department of the Army. The 106.03-acre landfill has been in operation since January 1974. The landfill contains household refuse, Post solid wastes, bulky items, grass and tree trimmings from family housing, refuse from litter cans, construction debris, classified waste (dry), dead animals, asbestos, and empty oil cans. The depth of the filled areas is about 30 feet and the cover, consisting of locally derived material, is 2 to 3 feet thick. Geologic and hydrologic data were collected at or adjacent to the landfill during (1) drilling of 10 30- to 31-foot boreholes that were completed with gas-monitoring probes, (2) drilling of a 59-foot borehole, (3) drilling of a 355-foot borehole that was completed as a ground-water monitoring well, and (4) in situ measurements made on the landfill cover. After completion, the gas- monitoring probes were monitored on a quarterly basis (1 year total) for gases generated by the landfill. Water samples were collected from the ground-water monitoring well for chemical analysis. Data collection is divided into two elements: geologic data and hydrologic data. Geologic data include lithologic descriptions of cores and cuttings, geophysical logs, soil- gas and ambient-air analyses, and chemical analyses of soil. Hydrologic data include physical properties, total organic carbon, and pH of soil and sediment samples; soil-water chloride and soil-moisture analyses; physical properties of the landfill cover; measurements of depth to ground water; and ground-water chemical analyses. Interpretation of data is not included in this report.

  4. Post-Closure Report for Closed Resource Conservation and Recovery Act Corrective Action Units, Nevada National Security Site, Nevada, for Fiscal Year 2014

    Energy Technology Data Exchange (ETDEWEB)

    Silvas, Alissa J. [Nevada Field Office, Las Vegas, NV (United States)

    2015-01-01

    This report serves as the combined annual report for post-closure activities for several Corrective Action Units (CAUs). The locations of the sites are shown in Figure 1. This report covers fiscal year 2014 (October 2013–September 2014). The post-closure requirements for these sites are described in Resource Conservation and Recovery Act Permit Number NEV HW0101 and summarized in each CAU-specific section in Section 1.0 of this report. The results of the inspections, a summary of maintenance activities, and an evaluation of monitoring data are presented in this report. Site inspections are conducted semiannually at CAUs 90 and 91 and quarterly at CAUs 92, 110, 111, and 112. Additional inspections are conducted at CAU 92 if precipitation occurs in excess of 0.50 inches (in.) in a 24-hour period and at CAU 111 if precipitation occurs in excess of 1.0 in. in a 24-hour period. Inspections include an evaluation of the condition of the units, including covers, fences, signs, gates, and locks. In addition to visual inspections, soil moisture monitoring, vegetation evaluations, and subsidence surveys are conducted at CAU 110. At CAU 111, soil moisture monitoring, vegetation evaluations, subsidence surveys, direct radiation monitoring, air monitoring, radon flux monitoring, and groundwater monitoring are conducted. The results of the vegetation surveys and an analysis of the soil moisture monitoring data at CAU 110 are presented in this report. Results of additional monitoring at CAU 111 are documented annually in the Nevada National Security Site Waste Management Monitoring Report Area 3 and Area 5 Radioactive Waste Management Sites and in the Nevada National Security Site Data Report: Groundwater Monitoring Program Area 5 Radioactive Waste Management Site, which will be prepared in approximately June 2015. All required inspections, maintenance, and monitoring were conducted in accordance with the post-closure requirements of the permit. It is recommended to continue

  5. Promoting Sound Ethical Decisions in the Air Force: CGO Solutions to Air Force Moral and Ethical Lapses

    Science.gov (United States)

    2014-07-01

    3Lolita Baldor and Robert Burns, “Air Force Drug Probe Widened to Include Cheating, Official Says.”Huffington Post, 17 March 2014. http...August 2012. Baldor , Lolita and Robert Burns, “Air Force Drug Probe Widened to Include Cheating, Official Says.”Huffington Post, 17 March 2014

  6. Geochemical evolution of Mexicali Valley groundwaters

    Energy Technology Data Exchange (ETDEWEB)

    Makdisi, R.S.; Truesdell, A.H.; Thompson, J.M.; Coplen, T.B.; Sanchez R., J.

    1982-08-10

    Isotopic and chemical compositions of Mexicali Valley groundwaters vary widely. Observed variations reflect different water origins, mineral-water reactions, lateral variations of delta facies as well as evaporation. Regional treatment of the groundwater data shows that northern and central regions are a mixture of old and new Colorado River water. Variations in water chemistry result from different groundwaters origins and the effects of lateral delta facies changes. Dissolution of gypsum and precipitation of carbonates, silicates, and phosphates are suggested. The eastern Mesa de San Luis and southern region water originates primarily from the Gila River catchment area. This water is undersaturated with respect to gypsum and carbonates and is oversaturated with respect to silicates. Most of the western groundwaters are a mixture of Colorado River and geothermal waters in the proximity of the Cerro Prieto geothermal field. Recharge to the geothermal aquifer is from the west as well as the north and east. Calcite is being precipitated out as the groundwater temperatures rise in response to the geothermal anomaly. Other western groundwaters reflect a dominant mixture of Colorado River water and evaporated lake water. Some Western groundwater samples suggest dilution by local rainwater and/or irrigation water.

  7. Groundwater in geologic processes, 2nd edition

    Science.gov (United States)

    Ingebritsen, Steven E.; Sanford, Ward E.; Neuzil, Christopher E.

    2006-01-01

    Interest in the role of Groundwater in Geologic Processes has increased steadily over the past few decades. Hydrogeologists and geologists are now actively exploring the role of groundwater and other subsurface fluids in such fundamental geologic processes as crustal heat transfer, ore deposition, hydrocarbon migration, earthquakes, tectonic deformation, diagenesis, and metamorphism.Groundwater in Geologic Processes is the first comprehensive treatment of this body of inquiry. Chapters 1 to 4 develop the basic theories of groundwater motion, hydromechanics, solute transport, and heat transport. Chapter 5 applies these theories to regional groundwater flow systems in a generic sense, and Chapters 6 to 13 focus on particular geologic processes and environments. Relative to the first edition of Groundwater in Geologic Processes , this second edition includes a much more comprehensive treatment of hydromechanics (the coupling of groundwater flow and deformation). It also includes new chapters on "compaction and diagenesis," "metamorphism," and "subsea hydrogeology." Finally, it takes advantage of the substantial body of published research that has appeared since the first edition in 1998. The systematic presentation of theory and application, and the problem sets that conclude each chapter, make this book ideal for undergraduate- and graduate-level geology courses (assuming that the students have some background in calculus and introductory chemistry). It also serves as an invaluable reference for researchers and other professionals in the field

  8. Groundwater Molybdenum from Emerging Industries in Taiwan.

    Science.gov (United States)

    Tsai, Kuo-Sheng; Chang, Yu-Min; Kao, Jimmy C M; Lin, Kae-Long

    2016-01-01

    This study determined the influence of emerging industries development on molybdenum (Mo) groundwater contamination. A total of 537 groundwater samples were collected for Mo determination, including 295 samples from potentially contaminated areas of 3 industrial parks in Taiwan and 242 samples from non-potentially contaminated areas during 2008-2014. Most of the high Mo samples are located downstream from a thin film transistor-liquid crystal display (TFT-LCD) panel factory. Mean groundwater Mo concentrations from potentially contaminated areas (0.0058 mg/L) were significantly higher (p groundwater and surface water contamination. Nine samples of groundwater exceed the World Health Organization's suggested drinking water guideline of 0.07 mg/L. A non-carcinogenic risk assessment for Mo in adults and children using the Mo concentration of 0.07 mg/L yielded risks of 0.546 and 0.215, respectively. These results indicate the importance of the development of a national drinking water quality standard for Mo in Taiwan to ensure safe groundwater for use. According to the human health risk calculation, the groundwater Mo standard is suggested as 0.07 mg/L. Reduction the discharge of Mo-contaminated wastewater from factories in the industrial parks is also the important task in the future.

  9. Ecosystem services in sustainable groundwater management.

    Science.gov (United States)

    Tuinstra, Jaap; van Wensem, Joke

    2014-07-01

    The ecosystem services concept seems to get foothold in environmental policy and management in Europe and, for instance, The Netherlands. With respect to groundwater management there is a challenge to incorporate this concept in such a way that it contributes to the sustainability of decisions. Groundwater is of vital importance to societies, which is reflected in the presented overview of groundwater related ecosystem services. Classifications of these services vary depending on the purpose of the listing (valuation, protection, mapping et cetera). Though the scientific basis is developing, the knowledge-availability still can be a critical factor in decision making based upon ecosystem services. The examples in this article illustrate that awareness of the value of groundwater can result in balanced decisions with respect to the use of ecosystem services. The ecosystem services concept contributes to this awareness and enhances the visibility of the groundwater functions in the decision making process. The success of the ecosystem services concept and its contribution to sustainable groundwater management will, however, largely depend on other aspects than the concept itself. Local and actual circumstances, policy ambitions and knowledge availability will play an important role. Solutions can be considered more sustainable when more of the key elements for sustainable groundwater management, as defined in this article, are fully used and the presented guidelines for long term use of ecosystem services are respected.

  10. Groundwater conditions in Utah, spring of 2013

    Science.gov (United States)

    Burden, Carole B.; Birken, Adam S.; Derrick, V. Noah; Fisher, Martel J.; Holt, Christopher M.; Downhour, Paul; Smith, Lincoln; Eacret, Robert J.; Gibson, Travis L.; Slaugh, Bradley A.; Whittier, Nickolas R.; Howells, James H.; Christiansen, Howard K.

    2013-01-01

    This is the fiftieth in a series of annual reports that describe groundwater conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing groundwater conditions. This report, like the others in the series, contains information on well construction, groundwater withdrawals from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of groundwater. Supplementary data are included in reports of this series only for those years or areas that are important to a discussion of changing groundwater conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of groundwater development in the State for calendar year 2012. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is also available online at http://www.waterrights.utah.gov/techinfo/ and http://ut.water. usgs.gov/publications/GW2013.pdf. Groundwater conditions in Utah for calendar year 2011 are reported in Burden and others (2012) and available online at http://ut.water.usgs.gov/ publications/GW2012.pdf

  11. From submarine to lacustrine groundwater discharge

    Science.gov (United States)

    Lewandowski, Jörg; Meinikmann, Karin; Pöschke, Franziska; Nützmann, Gunnar; Rosenberry, Donald O.

    2017-01-01

    Submarine groundwater discharge (SGD) and its role in marine nutrient cycling are well known since the last decade. The freshwater equivalent, lacustrine groundwater discharge (LGD), is often still disregarded, although first reports of LGD are more than 50 years old. We identify nine different reasons why groundwater has long been disregarded in both freshwater and marine environments such as invisibility of groundwater discharge, the size of the interface and its difficult accessibility. Although there are some fundamental differences in the hydrology of SGD and LGD, caused primarily by seawater recirculation that occurs only in cases of SGD, there are also a lot of similarities such as a focusing of discharge to near-shore areas. Nutrient concentrations in groundwater near the groundwater–surface water interface might be anthropogenically enriched. Due to spatial heterogeneity of aquifer characteristics and biogeochemical processes, the quantification of groundwater-borne nutrient loads is challenging. Both nitrogen and phosphorus might be mobile in near-shore aquifers and in a lot of case studies large groundwater-borne nutrient loads have been reported.

  12. Modelling Urban diffuse pollution in groundwater

    Science.gov (United States)

    Jato, Musa; Smith, Martin; Cundy, Andrew

    2017-04-01

    Diffuse urban pollution of surface and ground waters is a growing concern in many cities and towns. Traffic-derived pollutants such as salts, heavy metals and polycyclic aromatic hydrocarbons (PAHs) may wash off road surfaces in soluble or particulate forms which later drain through soils and drainage systems into surface waters and groundwater. In Brighton, about 90% of drinking water supply comes from groundwater (derived from the Brighton Chalk block). In common with many groundwater sources the Chalk aquifer has been relatively extensively monitored and assessed for diffuse rural contaminants such as nitrate, but knowledge on the extent of contamination from road run-off is currently lacking. This project examines the transfer of traffic-derived contaminants from the road surface to the Chalk aquifer, via urban drainage systems. A transect of five boreholes have been sampled on a monthly basis and groundwater samples analysed to examine the concentrations of key, mainly road run-off derived, hydrocarbon and heavy metal contaminants in groundwater across the Brighton area. Trace concentrations of heavy metals and phenols have been observed in groundwater. Electrical conductivity changes in groundwater have also been used to assess local changes in ionic strength which may be associated with road-derived contaminants. This has been supplemented by systematic water and sediment sampling from urban gully pots, with further sampling planned from drainage and settlement ponds adjacent to major roads, to examine initial road to drainage system transport of major contaminants.

  13. Hydroeconomic modeling of sustainable groundwater management

    Science.gov (United States)

    MacEwan, Duncan; Cayar, Mesut; Taghavi, Ali; Mitchell, David; Hatchett, Steve; Howitt, Richard

    2017-03-01

    In 2014, California passed legislation requiring the sustainable management of critically overdrafted groundwater basins, located primarily in the Central Valley agricultural region. Hydroeconomic modeling of the agricultural economy, groundwater, and surface water systems is critically important to simulate potential transition paths to sustainable management of the basins. The requirement for sustainable groundwater use by 2040 is mandated for many overdrafted groundwater basins that are decoupled from environmental and river flow effects. We argue that, for such cases, a modeling approach that integrates a biophysical response function from a hydrologic model into an economic model of groundwater use is preferable to embedding an economic response function in a complex hydrologic model as is more commonly done. Using this preferred approach, we develop a dynamic hydroeconomic model for the Kings and Tulare Lake subbasins of California and evaluate three groundwater management institutions—open access, perfect foresight, and managed pumping. We quantify the costs and benefits of sustainable groundwater management, including energy pumping savings, drought reserve values, and avoided capital costs. Our analysis finds that, for basins that are severely depleted, losses in crop net revenue are offset by the benefits of energy savings, drought reserve value, and avoided capital costs. This finding provides an empirical counterexample to the Gisser and Sanchez Effect.

  14. The shadow price of fossil groundwater

    Science.gov (United States)

    Bierkens, Marc F. P.; Reinhard, Stijn; de Bruijn, Jens A.; Wada, Yoshihide

    2017-04-01

    The expansion of irrigated agriculture into areas with limited precipitation and surface water during the growing season has greatly increased the use of fossil groundwater (Wada et al., 2012). As a result, the depletion rate of fossil groundwater resources has shown an increasing rate during the last decades (Wada et al, 2010; Konikow, 2011; Wada et al., 2012; De Graaf et al. 2015; Ritchy et al., 2015). Although water pricing has been used extensively to stimulate efficient application of water to create maximum value (e.g. Medellín-Azuara et al., 2012; Rinaudo et al., 2012; Dinar et al., 2015), it does not preclude the use of non-renewable water resources. Here, we use a global hydrological model and historical crop production and price data to assess the shadow price of non-renewable or fossil groundwater applied to major crops in countries that use large quantities of fossil groundwater. Our results show that shadow prices for many crops are very low, indicating economically inefficient or even wasteful use of fossil groundwater resources. Using India as an example, we show that small changes in the crop mix could lead to large reductions in fossil groundwater use or alternatively, create additional financial means to invest in water saving technologies. Our study thus provides a hydro-economic basis to further the sustainable use of finite groundwater resources.

  15. Review: Regional land subsidence accompanying groundwater extraction

    Science.gov (United States)

    Galloway, Devin L.; Burbey, Thomas J.

    2011-01-01

    The extraction of groundwater can generate land subsidence by causing the compaction of susceptible aquifer systems, typically unconsolidated alluvial or basin-fill aquifer systems comprising aquifers and aquitards. Various ground-based and remotely sensed methods are used to measure and map subsidence. Many areas of subsidence caused by groundwater pumping have been identified and monitored, and corrective measures to slow or halt subsidence have been devised. Two principal means are used to mitigate subsidence caused by groundwater withdrawal—reduction of groundwater withdrawal, and artificial recharge. Analysis and simulation of aquifer-system compaction follow from the basic relations between head, stress, compressibility, and groundwater flow and are addressed primarily using two approaches—one based on conventional groundwater flow theory and one based on linear poroelasticity theory. Research and development to improve the assessment and analysis of aquifer-system compaction, the accompanying subsidence and potential ground ruptures are needed in the topic areas of the hydromechanical behavior of aquitards, the role of horizontal deformation, the application of differential synthetic aperture radar interferometry, and the regional-scale simulation of coupled groundwater flow and aquifer-system deformation to support resource management and hazard mitigation measures.

  16. GARGLING WITH KETAMINE ATTENUATES POST-OPERATIVE SORE THROAT

    National Research Council Canada - National Science Library

    Tejashwini; Jagadish

    2014-01-01

    : INTRODUCTION: Postoperative Sore Throat (POST) is a common complication that is unresolved in patients undergoing endotracheal intubation, which is the foremost cause of trauma to the air way mucosa...

  17. 40 CFR 257.22 - Ground-water monitoring systems.

    Science.gov (United States)

    2010-07-01

    ... operator. When physical obstacles preclude installation of ground-water monitoring wells at the relevant... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water......

  18. Groundwater Quality Protection in Oakland County: A Sourcebook for Teachers.

    Science.gov (United States)

    East Michigan Environmental Action Council, Troy.

    This sourcebook consists of background information and activities related to groundwater protection. The first section focuses on the characteristics of groundwater, the water cycle, stormwater runoff, and uses of groundwater. The second section addresses household hazardous materials--both from a safety standpoint and a groundwater standpoint.…

  19. Groundwater Quality Protection in Oakland County: A Sourcebook for Teachers.

    Science.gov (United States)

    East Michigan Environmental Action Council, Troy.

    This sourcebook consists of background information and activities related to groundwater protection. The first section focuses on the characteristics of groundwater, the water cycle, stormwater runoff, and uses of groundwater. The second section addresses household hazardous materials--both from a safety standpoint and a groundwater standpoint.…

  20. Revised conceptualization of the North China Basin groundwater flow system: Groundwater age, heat and flow simulations

    Science.gov (United States)

    Cao, Guoliang; Han, Dongmei; Currell, Matthew J.; Zheng, Chunmiao

    2016-09-01

    Groundwater flow in deep sedimentary basins results from complex evolution processes on geological timescales. Groundwater flow systems conceptualized according to topography and/or groundwater table configuration generally assume a near-equilibrium state with the modern landscape. However, the time to reach such a steady state, and more generally the timescales of groundwater flow system evolution are key considerations for large sedimentary basins. This is true in the North China Basin (NCB), which has been studied for many years due to its importance as a groundwater supply. Despite many years of study, there remain contradictions between the generally accepted conceptual model of regional flow, and environmental tracer data. We seek to reconcile these contractions by conducting simulations of groundwater flow, age and heat transport in a three dimensional model, using an alternative conceptual model, based on geological, thermal, isotope and historical data. We infer flow patterns under modern hydraulic conditions using this new model and present the theoretical maximum groundwater ages under such a flow regime. The model results show that in contrast to previously accepted conceptualizations, most groundwater is discharged in the vicinity of the break-in-slope of topography at the boundary between the piedmont and central plain. Groundwater discharge to the ocean is in contrast small, and in general there are low rates of active flow in the eastern parts of the basin below the central and coastal plain. This conceptualization is more compatible with geochemical and geothermal data than the previous model. Simulated maximum groundwater ages of ∼1 Myrs below the central and coastal plain indicate that residual groundwater may be retained in the deep parts of the basin since being recharged during the last glacial period or earlier. The groundwater flow system has therefore probably not reached a new equilibrium state with modern-day hydraulic conditions. The

  1. Using Groundwater physiochemical properties for assessing potential earthquake precursor

    Science.gov (United States)

    Inbar, Nimrod; Reuveni, Yuval; Anker, Yaakov; Guttman, Joseph

    2017-04-01

    Worldwide studies reports pre-seismic, co-seismic and post-seismic reaction of groundwater to earthquakes. The unique hydrological and geological situation in Israel resulted in relatively deep water wells which are located close to seismically active tectonic plate boundary. Moreover, the Israeli experience show that anomalies may occurs 60-90 minutes prior to the seismic event (Guttman et al., 2005; Anker et al., 2016). Here, we try to assess the possible connection between changes in physiochemical parameters of groundwater and earthquakes along the Dead Sea Transform (DST) region. A designated network of monitoring stations was installed in MEKOROT abandoned deep water wells, continuously measuring water table, conductivity and temperature at a sampling rate of 1 minute. Preliminary analysis compares changes in the measured parameters with rain events, tidal effects and earthquake occurrences of all measured magnitudes (>2.5Md) at monitoring area surroundings. The acquired data set over one year recorded simultaneous abrupt changes in several wells which seems disconnected from standard hydrological occurrences such as precipitation, abstraction or tidal effects. At this stage, our research aims to determine and rationalize a baseline for "normal response" of the measured parameters to external occurrences while isolating those cases in which "deviations" from that base line is recorded. We apply several analysis techniques both in time and frequency domain with the measured signal as well as statistical analysis of several measured earthquake parameters, which indicate potential correlations between earthquakes occurrences and the measured signal. We show that at least in one seismic event (5.1 Md) a potential precursor may have been recorded. Reference: Anker, Y., N. Inbar, A. Y. Dror, Y. Reuveni, J. Guttman, A. Flexer, (2016). Groundwater response to ground movements, as a tool for earthquakes monitoring and a possible precursor. 8th International Conference

  2. AUTOMATING GROUNDWATER SAMPLING AT HANFORD THE NEXT STEP

    Energy Technology Data Exchange (ETDEWEB)

    CONNELL CW; CONLEY SF; HILDEBRAND RD; CUNNINGHAM DE; R_D_Doug_Hildebrand@rl.gov; DeVon_E_Cunningham@rl.gov

    2010-01-21

    Historically, the groundwater monitoring activities at the Department of Energy's Hanford Site in southeastern Washington State have been very "people intensive." Approximately 1500 wells are sampled each year by field personnel or "samplers." These individuals have been issued pre-printed forms showing information about the well(s) for a particular sampling evolution. This information is taken from 2 official electronic databases: the Hanford Well information System (HWIS) and the Hanford Environmental Information System (HEIS). The samplers used these hardcopy forms to document the groundwater samples and well water-levels. After recording the entries in the field, the samplers turned the forms in at the end of the day and other personnel posted the collected information onto a spreadsheet that was then printed and included in a log book. The log book was then used to make manual entries of the new information into the software application(s) for the HEIS and HWIS databases. A pilot project for automating this extremely tedious process was lauched in 2008. Initially, the automation was focused on water-level measurements. Now, the effort is being extended to automate the meta-data associated with collecting groundwater samples. The project allowed electronic forms produced in the field by samplers to be used in a work flow process where the data is transferred to the database and electronic form is filed in managed records - thus eliminating manually completed forms. Elimating the manual forms and streamlining the data entry not only improved the accuracy of the information recorded, but also enhanced the efficiency and sampling capacity of field office personnel.

  3. Coastal hazards and groundwater salinization on low coral islands.

    Science.gov (United States)

    Terry, James P.; Chui, T. F. May

    2016-04-01

    Remote oceanic communities living on low-lying coral islands (atolls) without surface water rely for their survival on the continuing viability of fragile groundwater resources. These exist in the form of fresh groundwater lenses (FGLs) that develop naturally within the porous coral sand and gravel substrate. Coastal hazards such as inundation by high-energy waves driven by storms and continuing sea-level rise (SLR) are among many possible threats to viable FGL size and quality on atolls. Yet, not much is known about the combined effects of wave washover during powerful storms and SLR on different sizes of coral island, nor conversely how island size influences lens resilience against damage. This study investigates FGL damage by salinization (and resilience) caused by such coastal hazards using a modelling approach. Numerical modelling is carried out to generate steady-state FGL configurations at three chosen island sizes (400, 600 and 800 m widths). Steady-state solutions reveal how FGL dimensions are related in a non-linear manner to coral island size, such that smaller islands develop much more restricted lenses than larger islands. A 40 cm SLR scenario is then imposed. This is followed by transient simulations to examine storm-induced wave washover and subsequent FGL responses to saline damage over a 1 year period. Smaller FGLs display greater potential for disturbance by SLR, while larger and more robust FGLs tend to show more resilience. Further results produce a somewhat counterintuitive finding: in the post-SLR condition, FGL vulnerability to washover salinization may actually be reduced, owing to the thinner layer of unsaturated substrate lying above the water table into which saline water can infiltrate during a storm event. Nonetheless, combined washover and SLR impacts imply overall that advancing groundwater salinization may lead to some coral islands becoming uninhabitable long before they are completely submerged by sea-level rise, thereby calling

  4. TREATABILITY TEST FOR REMOVING TECHNETIUM-99 FROM 200-ZP-1 GROUNDWATER HANFORD SITE

    Energy Technology Data Exchange (ETDEWEB)

    PETERSEN SW; TORTOSO AC; ELLIOTT WS; BYRNES ME

    2007-11-29

    The 200-ZP-1 Groundwater Operable Unit (OU) is one of two groundwater OUs located within the 200 West groundwater aggregate area of the Hanford Site. The primary risk-driving contaminants within the 200-ZP-1 OU include carbon tetrachloride and technetium-99 (Tc-99). A pump-and-treat system for this OU was initially installed in 1995 to control the 0.002 kg/m{sup 3} (2000 {micro}g/L) contour of the carbon tetrachloride plume. Carbon tetrachloride is removed from groundwater with the assistance of an air-stripping tower. Ten extraction wells and three injection wells operate at a combined rate of approximately 0.017m{sup 3}/s (17.03 L/s). In 2005, groundwater from two of the extraction wells (299-W15-765 and 299-W15-44) began to show concentrations greater than twice the maximum contaminant level (MCL) of Tc-99 (33,309 beq/m{sup 3} or 900 pCi/L). The Tc-99 groundwater concentrations from all ten of the extraction wells when mixed were more than one-half of the MCL and were slowly increasing. If concentrations continued to rise and the water remained untreated for Tc-99, there was concern that the water re-injected into the aquifer could exceed the MCL standard. Multiple treatment technologies were reviewed for selectively removing Tc-99 from the groundwater. Of the treatment technologies, only ion exchange was determined to be highly selective, commercially available, and relatively low in cost. Through research funded by the U.S. Department of Energy, the ion-exchange resin Purolite{reg_sign} A-530E was found to successfully remove Tc-99 from groundwater, even in the presence of competing anions. For this and other reasons, Purolite{reg_sign} A-530E ion exchange resin was selected for treatability testing. The treatability test required installing resin columns on the discharge lines from extraction wells 299-W15-765 and 299-W15-44. Preliminary test results have concluded that the Purolite{reg_sign} A-530E resin is effective at removing Tc-99 from groundwater to

  5. Air Pollution

    Science.gov (United States)

    ... to view this content or go to source URL . What NIEHS is Doing on Air Pollution Who ... Junction Last Reviewed: February 06, 2017 This page URL: NIEHS website: https://www.niehs.nih.gov/ Email ...

  6. Groundwater Data Package for Hanford Assessments

    Energy Technology Data Exchange (ETDEWEB)

    Thorne, Paul D.; Bergeron, Marcel P.; Williams, Mark D.; Freedman, Vicky L.

    2006-01-31

    This report presents data and interpreted information that supports the groundwater module of the System Assessment Capability (SAC) used in Hanford Assessments. The objective of the groundwater module is to predict movement of radioactive and chemical contaminants through the aquifer to the Columbia River or other potential discharge locations. This data package is being revised as part of the deliverables under the Characterization of Systems Project (#49139) aimed at providing documentation for assessments being conducted under the Hanford Assessments Project (#47042). Both of these projects are components of the Groundwater Remediation and Closure Assessments Projects, managed by the Management and Integration Project (#47043).

  7. Burn site groundwater interim measures work plan.

    Energy Technology Data Exchange (ETDEWEB)

    Witt, Jonathan L. (North Wind, Inc., Idaho Falls, ID); Hall, Kevin A. (North Wind, Inc., Idaho Falls, ID)

    2005-05-01

    This Work Plan identifies and outlines interim measures to address nitrate contamination in groundwater at the Burn Site, Sandia National Laboratories/New Mexico. The New Mexico Environment Department has required implementation of interim measures for nitrate-contaminated groundwater at the Burn Site. The purpose of interim measures is to prevent human or environmental exposure to nitrate-contaminated groundwater originating from the Burn Site. This Work Plan details a summary of current information about the Burn Site, interim measures activities for stabilization, and project management responsibilities to accomplish this purpose.

  8. Environmental monitoring final report: groundwater chemical analyses

    Energy Technology Data Exchange (ETDEWEB)

    1984-02-01

    This report presents the results of analyses of groundwater qualtiy at the SRC-I Demonstration Plant site in Newman, Kentucky. Samples were obtained from a network of 23 groundwater observation wells installed during previous studies. The groundwater was well within US EPA Interim Primary Drinking Water Standards for trace metals, radioactivity, and pesticides, but exceeded the standard for coliform bacteria. Several US EPA Secondary Drinking Water Standards were exceeded, namely, manganese, color, iron, and total dissolved solids. Based on the results, Dames and Moore recommend that all wells should be sterilized and those wells built in 1980 should be redeveloped. 1 figure, 6 tables.

  9. Movement and fate of detergents in groundwater: a field study

    Science.gov (United States)

    Thurman, E.M.; Barber, L.B.; LeBlanc, D.

    1986-01-01

    The major cations, anions, and detergents in a plume of contaminated groundwater at Otis Air Base on Cape Cod (Mass., U.S.A.) have moved approximately 3.5 km down gradient from the disposal beds. We hypothesize that the detergents form two distinct plumes, which consist of alkyl benzene sulfonates (ABS) detergents and linear alkyl sulfonates (LAS) and sodium dodecyl sulfate (NaLS) detergents. The ABS detergents were deposited from approximately 1940 through 1965, when ABS detergents were banned. From 1965 to the present, LAS and NaLS detergents were in the sewage. The ABS detergents appear to be transported in the aquifer at the same rate as the specific conductance (major cations and anions) and boron, which are currently used as conservative tracers of the plume of contaminated groundwater. There appears to be little or no biological degradation of the ABS detergents in the aquifer, based on their concentration in the plume. On the other hand, the LAS and NaLS detergents have degraded rapidly and have been detected only 0.6 km down gradient. The roleof the detergents in the transport of other organic compounds in the plume is nuclear. There is a separation of the ABS detergent plume and the volatile organic compound plume; however, the time of entry of the detergents and the volatile organic compounds is unknown. Therefore, it is not possible to conclude on the interaction of these two classes of compounds. ?? 1986.

  10. Seasonal variation of redox species and redox potentials in shallow groundwater: A comparison of measured and calculated redox potentials

    Science.gov (United States)

    Ramesh Kumar, A.; Riyazuddin, P.

    2012-06-01

    SummaryThe seasonal variation of redox potential (Eh) and redox species such as As(V)/As(III), Cr(VI)/Cr(III), Fe(III)/Fe(II), NO3-/NO2-, and Se(VI)/Se(IV) were studied in a shallow groundwater for a period of three years (May, 2004-January, 2007). The study area was Chrompet area of Chennai city, India. Groundwater samples from 65 wells were monitored for pH, electrical conductivity, dissolved oxygen (DO), and major ions during pre-(May) and post-monsoon (January) seasons. The objective of the study was to gain insight into the temporal variation of the redox species due to groundwater recharge and to identify the redox reactions controlling the measured Eh of the groundwater. The study revealed that the shallow groundwater was "oxic" with DO ranging between 0.25 and 5.00 mg L-1, and between 0.38 and 5.05 mg L-1 during pre-(May, 2004) and post-monsoon (January, 2005) seasons, respectively. The measured Eh (with respect to standard hydrogen electrode, SHE) ranged between 65 and 322 mV, and between 110 and 330 mV during pre- and post-monsoon seasons, respectively. During post-monsoon seasons, DO and Eh increased in most of the wells due to groundwater recharge. The calculated Eh using the redox couples As(V)/As(III), NO3-/NO2-, O2/H2O and Se(VI)/Se(IV) neither agreed among themselves nor with the measured Eh during all the seasons. It shows that in the shallow groundwater, the various redox couples are in disequilibrium among themselves and with the Pt electrode. However, 41% (n = 122) of the Eh values calculated from Fe(III)/Fe(II) couple agreed with the measured Eh within ±30 mV, the uncertainty of Pt-electrode measurement. The post-monsoon seasons showed higher values of As(V)/As(III) and Se(VI)/Se(IV) compared to the pre-monsoon seasons, whereas Fe(III)/Fe(II) behaved in the opposite manner. This pattern of variation is consistent with the increased oxidizing nature, as shown by the higher DO and Eh values observed during post-monsoon seasons. The results

  11. Uncertainty in global groundwater storage estimates in a Total Groundwater Stress framework

    Science.gov (United States)

    Richey, Alexandra S.; Thomas, Brian F.; Lo, Min‐Hui; Swenson, Sean; Rodell, Matthew

    2015-01-01

    Abstract Groundwater is a finite resource under continuous external pressures. Current unsustainable groundwater use threatens the resilience of aquifer systems and their ability to provide a long‐term water source. Groundwater storage is considered to be a factor of groundwater resilience, although the extent to which resilience can be maintained has yet to be explored in depth. In this study, we assess the limit of groundwater resilience in the world's largest groundwater systems with remote sensing observations. The Total Groundwater Stress (TGS) ratio, defined as the ratio of total storage to the groundwater depletion rate, is used to explore the timescales to depletion in the world's largest aquifer systems and associated groundwater buffer capacity. We find that the current state of knowledge of large‐scale groundwater storage has uncertainty ranges across orders of magnitude that severely limit the characterization of resilience in the study aquifers. Additionally, we show that groundwater availability, traditionally defined as recharge and redefined in this study as total storage, can alter the systems that are considered to be stressed versus unstressed. We find that remote sensing observations from NASA's Gravity Recovery and Climate Experiment can assist in providing such information at the scale of a whole aquifer. For example, we demonstrate that a groundwater depletion rate in the Northwest Sahara Aquifer System of 2.69 ± 0.8 km3/yr would result in the aquifer being depleted to 90% of its total storage in as few as 50 years given an initial storage estimate of 70 km3. PMID:26900184

  12. Are Agricultural Measures for Groundwater Protection Beneficial When Compared to Purification of Polluted Groundwater?

    OpenAIRE

    Hasler, Berit; Lundhede, Thomas

    2005-01-01

    The groundwater resource, the drinking water areas and the surface water quality can be protected by measures, e.g. by reductions of pesticide and nutrient applications, conversion of arable land to grasslands or forests etc. The objective of the paper is to estimate the benefits of groundwater protection by the valuation method choice experiments. This method allows for separate estimation and comparison of the different attributes connected to groundwater protection i.e. the effects on drin...

  13. Military uses of groundwater: a driver of innovation?

    Science.gov (United States)

    Robins, N. S.; Rose, E. P. F.

    2009-07-01

    Military need has been a positive driver to the development of the modern day, and now mature, science of hydrogeology. The important synergy between geology and water supply was appreciated by military men in the mid-nineteenth century but the first real test of this learning only took place in the First World War. German, British and American geologists then mapped water resources and the potential for exploiting groundwater in Belgium and northern France. Technical innovations included deployment of rapid drilling techniques and the promotion of well screens for use in unconsolidated sediments. The mapping techniques were developed further during the Second World War when innovative remote mapping of enemy-occupied territory became an important planning tool to both Allied and German armies. Work in North Africa and other arid and semi-arid terrains promoted insight into the occurrence of groundwater in fresh-water aquifers little replenished by recharge. Mapping of hard rock basement-type environments in the islands of Jersey and Guernsey by German geologists was a concept new to the British Isles. Collectively, these varied initiatives provided part of the foundation for post-Second World War development of modern-day applied hydrogeology.

  14. Baseline groundwater chemistry characterization in an area of future Marcellus shale gas development

    Science.gov (United States)

    Eisenhauer, P.; Zegre, N.; Edwards, P. J.; Strager, M.

    2012-12-01

    The recent increase in development of the Marcellus shale formation for natural gas in the mid-Atlantic can be attributed to advances in unconventional extraction methods, namely hydraulic fracturing, a process that uses water to pressurize and fracture relatively impermeable shale layers to release natural gas. In West Virginia, the Department of Energy estimates 95 to 105 trillion cubic feet (TCF) of expected ultimately recovery (EUR) of natural gas for this formation. With increased development of the Marcellus shale formation comes concerns for the potential of contamination to groundwater resources that serve as primary potable water sources for many rural communities. However, the impacts of this practice on water resources are poorly understood because of the lack of controlled pre versus post-drilling experiments attributed to the rapid development of this resource. To address the knowledge gaps of the potential impacts of Marcellus shale development on groundwater resources, a pre versus post-drilling study has been initiated by the USFS Fernow Experimental Forest in the Monongahela National Forest. Drilling is expected to start at three locations within the next year. Pre-drilling water samples were collected and analyzed from two groundwater wells, a shallow spring, a nearby lake, and river to characterize background water chemistry and identify potential end-members. Geochemical analysis includes major ions, methane, δ13C-CH4, δ2H-CH4, 226Radium, and δ13C-DIC. In addition, a GIS-based conceptual ground water flow model was developed to identify possible interactions between shallow groundwater and natural gas wells given gas well construction failure. This model is used to guide management decisions regarding groundwater resources in an area of increasing shale gas development.

  15. Physicochemical quality evaluation of groundwater and development of drinking water quality index for Araniar River Basin, Tamil Nadu, India.

    Science.gov (United States)

    Jasmin, I; Mallikarjuna, P

    2014-02-01

    Groundwater is the most important natural resource which cannot be optimally used and sustained unless its quality is properly assessed. In the present study, the spatial and temporal variations in physicochemical quality parameters of groundwater of Araniar River Basin, India were analyzed to determine its suitability for drinking purpose through development of drinking water quality index (DWQI) maps of the post- and pre-monsoon periods. The suitability for drinking purpose was evaluated by comparing the physicochemical parameters of groundwater in the study area with drinking water standards prescribed by the World Health Organization (WHO) and Bureau of Indian Standards (BIS). Interpretation of physicochemical data revealed that groundwater in the basin was slightly alkaline. The cations such as sodium (Na(+)) and potassium (K(+)) and anions such as bicarbonate (HCO3 (-)) and chloride (Cl(-)) exceeded the permissible limits of drinking water standards (WHO and BIS) in certain pockets in the northeastern part of the basin during the pre-monsoon period. The higher total dissolved solids (TDS) concentration was observed in the northeastern part of the basin, and the parameters such as calcium (Ca(2+)), magnesium (Mg(2+)), sulfate (SO4 (2-)), nitrate (NO3 (-)), and fluoride (F(-)) were within the limits in both the seasons. The hydrogeochemical evaluation of groundwater of the basin demonstrated with the Piper trilinear diagram indicated that the groundwater samples of the area were of Ca(2+)-Mg(2+)-Cl(-)-SO4 (2-), Ca(2+)-Mg(2+)-HCO3 (-) and Na(+)-K(+)-Cl(-)-SO4 (2-) types during the post-monsoon period and Ca(2+)-Mg(2+)-Cl(-)-SO4 (2-), Na(+)-K(+)-Cl(-)-SO4 (2-) and Ca(2+)-Mg(2+)-HCO3 (-) types during the pre-monsoon period. The DWQI maps for the basin revealed that 90.24 and 73.46% of the basin area possess good quality drinking water during the post- and pre-monsoon seasons, respectively.

  16. Shallow groundwater thermal sensitivity to climate change and land cover disturbances: derivation of analytical expressions and implications for stream temperature projections

    Directory of Open Access Journals (Sweden)

    B. L. Kurylyk

    2014-11-01

    Full Text Available Climate change is expected to increase stream temperatures, and the projected warming may alter the spatial extent of habitat for coldwater fish and other aquatic taxa. Recent studies have proposed that stream thermal sensitivities, derived from short term air temperature variations, can be employed to infer future stream warming due to long term climate change. However, this approach does not consider the potential for streambed heat fluxes to increase due to gradual warming of shallow groundwater. The temperature of shallow groundwater is particularly important for the thermal regimes of groundwater-dominated streams and rivers. Also, other recent stream temperature studies have investigated how land surface perturbations, such as wildfires or timber harvesting, can influence stream temperatures by changing surface heat fluxes, but these studies have typically not considered how these surface disturbances can also alter shallow groundwater temperatures and consequent streambed heat fluxes. In this study, several analytical solutions to the one-dimensional unsteady advection–diffusion equation for subsurface heat transport are employed to investigate the timing and magnitude of groundwater warming due to seasonal and long term variability in land surface temperatures. Novel groundwater thermal sensitivity formulae are proposed that accommodate different surface warming scenarios. The thermal sensitivity formulae demonstrate that shallow groundwater will warm in response to climate change and other surface perturbations, but the timing and magnitude of the warming depends on the rate of surface warming, subsurface thermal properties, aquifer depth, and groundwater velocity. The results also emphasize the difference between the thermal sensitivity of shallow groundwater to short term (e.g. seasonal and long term (e.g. multi-decadal land surface temperature variability, and thus demonstrate the limitations of using short term air and water

  17. Simulation of Groundwater Flow, Denpasar-Tabanan Groundwater Basin, Bali Province

    Directory of Open Access Journals (Sweden)

    Heryadi Tirtomihardjo

    2014-06-01

    Full Text Available DOI: 10.17014/ijog.v6i3.123Due to the complex structure of the aquifer systems and its hydrogeological units related with the space in which groundwater occurs, groundwater flows were calculated in three-dimensional method (3D Calculation. The geometrical descritization and iteration procedures were based on an integrated finite difference method. In this paper, all figures and graphs represent the results of the calibrated model. Hence, the model results were simulated by using the actual input data which were calibrated during the simulation runs. Groundwater flow simulation of the model area of the Denpasar-Tabanan Groundwater Basin (Denpasar-Tabanan GB comprises steady state run, transient runs using groundwater abstraction in the period of 1989 (Qabs-1989 and period of 2009 (Qabs-2009, and prognosis run as well. Simulation results show, in general, the differences of calculated groundwater heads and observed groundwater heads at steady and transient states (Qabs-1989 and Qabs-2009 are relatively small. So, the groundwater heads situation simulated by the prognosis run (scenario Qabs-2012 are considerably valid and can properly be used for controlling the plan of groundwater utilization in Denpasar-Tabanan GB.

  18. River-groundwater connectivity in a karst system, Wellington, New South Wales, Australia

    Science.gov (United States)

    Keshavarzi, Mohammadreza; Baker, Andy; Kelly, Bryce F. J.; Andersen, Martin S.

    2017-03-01

    The characterization of river-aquifer connectivity in karst environments is difficult due to the presence of conduits and caves. This work demonstrates how geophysical imaging combined with hydrogeological data can improve the conceptualization of surface-water and groundwater interactions in karst terrains. The objective of this study is to understand the association between the Bell River and karst-alluvial aquifer at Wellington, Australia. River and groundwater levels were continuously monitored, and electrical resistivity imaging and water quality surveys conducted. Two-dimensional resistivity imaging mapped the transition between the alluvium and karst. This is important for highlighting the proximity of the saturated alluvial sediments to the water-filled caves and conduits. In the unsaturated zone the resistivity imaging differentiated between air- and sediment-filled karst features, and in the saturated zone it mapped the location of possible water- and sediment-filled caves. Groundwater levels are dynamic and respond quickly to changes in the river stage, implying that there is a strong hydraulic connection, and that the river is losing and recharging the adjacent aquifer. Groundwater extractions (1,370 ML, megalitres, annually) from the alluvial aquifer can cause the groundwater level to fall by as much as 1.5 m in a year. However, when the Bell River flows after significant rainfall in the upper catchment, river-leakage rapidly recharges the alluvial and karst aquifers. This work demonstrates that in complex hydrogeological settings, the combined use of geophysical imaging, hydrograph analysis and geochemical measurements provide insights on the local karst hydrology and groundwater processes, which will enable better water-resource and karst management.

  19. River-groundwater connectivity in a karst system, Wellington, New South Wales, Australia

    Science.gov (United States)

    Keshavarzi, Mohammadreza; Baker, Andy; Kelly, Bryce F. J.; Andersen, Martin S.

    2016-12-01

    The characterization of river-aquifer connectivity in karst environments is difficult due to the presence of conduits and caves. This work demonstrates how geophysical imaging combined with hydrogeological data can improve the conceptualization of surface-water and groundwater interactions in karst terrains. The objective of this study is to understand the association between the Bell River and karst-alluvial aquifer at Wellington, Australia. River and groundwater levels were continuously monitored, and electrical resistivity imaging and water quality surveys conducted. Two-dimensional resistivity imaging mapped the transition between the alluvium and karst. This is important for highlighting the proximity of the saturated alluvial sediments to the water-filled caves and conduits. In the unsaturated zone the resistivity imaging differentiated between air- and sediment-filled karst features, and in the saturated zone it mapped the location of possible water- and sediment-filled caves. Groundwater levels are dynamic and respond quickly to changes in the river stage, implying that there is a strong hydraulic connection, and that the river is losing and recharging the adjacent aquifer. Groundwater extractions (1,370 ML, megalitres, annually) from the alluvial aquifer can cause the groundwater level to fall by as much as 1.5 m in a year. However, when the Bell River flows after significant rainfall in the upper catchment, river-leakage rapidly recharges the alluvial and karst aquifers. This work demonstrates that in complex hydrogeological settings, the combined use of geophysical imaging, hydrograph analysis and geochemical measurements provide insights on the local karst hydrology and groundwater processes, which will enable better water-resource and karst management.

  20. Spatial and temporal variation of groundwater quality and its suitability for irrigation and drinking purpose using GIS and WQI in an urban fringe

    Science.gov (United States)

    Dhanasekarapandian, M.; Chandran, S.; Devi, D. Saranya; Kumar, V.

    2016-12-01

    This study is aimed at evaluating the groundwater quality within the urban reach of Gridhumal river sub-basin. 29 groundwater samples were collected with different categorization during post-monsoon (POM) and summer (SUM) seasons respectively. Various physical and chemical parameters viz., pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Total Hardness (TH), Total Alkalinity, cations such as, Ca2+, Mg2+, Na+, anions such as NO3-, SO42-, F-, Cl- were analyzed and were compared with the standard guidelines recommended by WHO, ICMR, BIS. GIS techniques were used to find out the distribution of groundwater quality on land use pattern. Results indicated that the EC, TDS, TH, Na+, Cl-, NO3- level in groundwater samples was above critical limits, and it was found to be very high in wastewater irrigated areas in the urban reach of Gridhumal river sub-basin. Geochemical analysis of groundwater samples shows the predominance of Na-Cl and NaHCO3 types. The geochemical data was interpreted using WQI for drinking water quality and were found not suitable for drinking purposes. With Wilcox diagram, only 30% and 21% groundwater samples show suitability for irrigation for post monsoon and summer season. The US Salinity Laboratory Staff plot depicted that all the post monsoon groundwater sources are C3-S3, C4-S4 type and C4-S4 for the summer season. 17% samples show C3-S1 type for both the season. From the HC analysis in the groundwater samples have been classified into two groups, one is ionic and another metals group. PCA results revealed the existence of seven significant principal components indicating how processes like rock-water interaction and anthropogenic activities influence groundwater quality. Seven factors which together explain 83.33% and 77.85% of the total variance in the post monsoon and summer season respectively. In comparing heavy metal contents present in water samples with BIS/WHO standards, Pb, Cr and Cd concentrations were found to be present

  1. Groundwater Surface Trends at Van Norden Meadow, California, from Ground Penetrating Radar Profiles

    Science.gov (United States)

    Tadrick, N. I.; Blacic, T. M.; Yarnell, S. M.

    2014-12-01

    Van Norden meadow in the Donner Summit area west of Lake Tahoe is one of the largest sub-alpine meadows in the Sierra Nevada mountain range. As natural water retention basins, meadows attenuate floods, improve water quality and support vegetation that stabilizes stream banks and promotes high biodiversity. Like most meadows in the Sierras however, over-grazing, road-building, and development has resulted in localized stream incision, degradation, and partial conversion from wet to dry conditions in Van Norden. Additionally, a small dam at the base of the meadow has partially flooded the lower meadow creating reservoir conditions. Privately owned since the late 1800s, Van Norden was recently purchased by a local land trust to prevent further development and return the area to public ownership. Restoration of the natural meadow conditions will involve notching the dam in 2016 to reduce currently impounded water volumes from 250 to less than 50 acre-feet. To monitor the effects of notching the dam on the upstream meadow conditions, better understanding of the surface and groundwater hydrology both pre- and post-restoration is required. We surveyed the meadow in summer 2014 with ground penetrating radar (GPR) to map the groundwater surface prior to restoration activities using a 270MHz antenna to obtain a suite of longitudinal and transverse transects. Groundwater level within the meadow was assessed using both piezometer readings and sweeps of the GPR antenna. Seventeen piezometers were added this year to the 13 already in place to monitor temporal changes in the groundwater surface, while the GPR profiles provided information about lateral variations. Our results provide an estimate of the groundwater depth variations across the upper portion of the meadow before notching. We plan to return in 2015 to collect GPR profiles during wetter conditions, which will provide a more complete assessment of the pre-notching groundwater hydrology.

  2. Assessment of groundwater quality: a fusion of geochemical and geophysical information via Bayesian neural networks.

    Science.gov (United States)

    Maiti, Saumen; Erram, V C; Gupta, Gautam; Tiwari, Ram Krishna; Kulkarni, U D; Sangpal, R R

    2013-04-01

    Deplorable quality of groundwater arising from saltwater intrusion, natural leaching and anthropogenic activities is one of the major concerns for the society. Assessment of groundwater quality is, therefore, a primary objective of scientific research. Here, we propose an artificial neural network-based method set in a Bayesian neural network (BNN) framework and employ it to assess groundwater quality. The approach is based on analyzing 36 water samples and inverting up to 85 Schlumberger vertical electrical sounding data. We constructed a priori model by suitably parameterizing geochemical and geophysical data collected from the western part of India. The posterior model (post-inversion) was estimated using the BNN learning procedure and global hybrid Monte Carlo/Markov Chain Monte Carlo optimization scheme. By suitable parameterization of geochemical and geophysical parameters, we simulated 1,500 training samples, out of which 50 % samples were used for training and remaining 50 % were used for validation and testing. We show that the trained model is able to classify validation and test samples with 85 % and 80 % accuracy respectively. Based on cross-correlation analysis and Gibb's diagram of geochemical attributes, the groundwater qualities of the study area were classified into following three categories: "Very good", "Good", and "Unsuitable". The BNN model-based results suggest that groundwater quality falls mostly in the range of "Good" to "Very good" except for some places near the Arabian Sea. The new modeling results powered by uncertainty and statistical analyses would provide useful constrain, which could be utilized in monitoring and assessment of the groundwater quality.

  3. Evaluating influences of seasonal variations and anthropogenic activities on alluvial groundwater hydrochemistry using ensemble learning approaches

    Science.gov (United States)

    Singh, Kunwar P.; Gupta, Shikha; Mohan, Dinesh

    2014-04-01

    Chemical composition and hydrochemistry of groundwater is influenced by the seasonal variations and anthropogenic activities in a region. Understanding of such influences and responsible factors is vital for the effective management of groundwater. In this study, ensemble learning based classification and regression models are constructed and applied to the groundwater hydrochemistry data of Unnao and Ghaziabad regions of northern India. Accordingly, single decision tree (SDT), decision tree forest (DTF), and decision treeboost (DTB) models were constructed. Predictive and generalization abilities of the proposed models were investigated using several statistical parameters and compared with the support vector machines (SVM) method. The DT and SVM models discriminated the groundwater in shallow and deep aquifers, industrial and non-industrial areas, and pre- and post-monsoon seasons rendering misclassification rate (MR) between 1.52-14.92% (SDT); 0.91-6.52% (DTF); 0.61-5.27% (DTB), and 1.52-11.69% (SVM), respectively. The respective regression models yielded a correlation between measured and predicted values of COD and root mean squared error of 0.874, 0.66 (SDT); 0.952, 0.48 (DTF); 0.943, 0.52 (DTB); and 0.785, 0.85 (SVR) in complete data array of Ghaziabad. The DTF and DTB models outperformed the SVM both in classification and regression. It may be noted that incorporation of the bagging and stochastic gradient boosting algorithms in DTF and DTB models, respectively resulted in their enhanced predictive ability. The proposed ensemble models successfully delineated the influences of seasonal variations and anthropogenic activities on groundwater hydrochemistry and can be used as effective tools for forecasting the chemical composition of groundwater for its management.

  4. Investigation of the geochemical evolution of groundwater under agricultural land: A case study in northeastern Mexico

    Science.gov (United States)

    Ledesma-Ruiz, Rogelio; Pastén-Zapata, Ernesto; Parra, Roberto; Harter, Thomas; Mahlknecht, Jürgen

    2015-02-01

    Zona Citrícola is an important area for Mexico due to its citriculture activity. Situated in a sub-humid to humid climate adjacent to the Sierra Madre Oriental, this valley hosts an aquifer system that represents sequences of shales, marls, conglomerates, and alluvial deposits. Groundwater flows from mountainous recharge areas to the basin-fill deposits and provides base flows to supply drinking water to the adjacent metropolitan area of Monterrey. Recent studies examining the groundwater quality of the study area urge the mitigation of groundwater pollution. The objective of this study was to characterize the physical and chemical properties of the groundwater and to assess the processes controlling the groundwater's chemistry. Correlation was used to identify associations among various geochemical constituents. Factor analysis was applied to identify the water's chemical characteristics that were responsible for generating most of the variability within the dataset. Hierarchical cluster analysis was employed in combination with a post-hoc analysis of variance to partition the water samples into hydrochemical water groups: recharge waters (Ca-HCO3), transition zone waters (Ca-HCO3-SO4 to Ca-SO4-HCO3) and discharge waters (Ca-SO4). Inverse geochemical models of these groups were developed and constrained using PHREEQC to elucidate the chemical reactions controlling the water's chemistry between an initial (recharge) and final water. The primary reactions contributing to salinity were the following: (1) water-rock interactions, including the weathering of evaporitic rocks and dedolomitization; (2) dissolution of soil gas carbon dioxide; and (3) input from animal/human wastewater and manure in combination with by denitrification processes. Contributions from silicate weathering to salinity ranged from less important to insignificant. The findings suggest that it may not be cost-effective to regulate manure application to mitigate groundwater pollution.

  5. Shallow groundwater effect on land surface temperature and surface energy balance under bare soil conditions: modeling and description

    Directory of Open Access Journals (Sweden)

    F. Alkhaier

    2011-09-01

    Full Text Available Appreciating when and how groundwater affects surface temperature and energy fluxes is important for utilizing remote sensing in groundwater studies and for integrating aquifers within land surface models. To explore the shallow groundwater effect, we numerically exposed two soil profiles – one having shallow groundwater – to the same meteorological forcing, and inspected their different responses regarding surface soil moisture, temperature and energy balance. We found that the two profiles differed in the absorbed and emitted amounts of energy, in portioning out the available energy and in heat fluency within the soil. We conclude that shallow groundwater areas reflect less shortwave radiation due to their lower albedo and therefore they get higher magnitude of net radiation. When potential evaporation demand is high enough, a large portion of the energy received by these areas is spent on evaporation. This makes the latent heat flux predominant, and leaves less energy to heat the soil. Consequently, this induces lower magnitudes of both sensible and ground heat fluxes. The higher soil thermal conductivity in shallow groundwater areas facilitates heat transfer between the top soil and the subsurface, i.e. soil subsurface is more thermally connected to the atmosphere. In view of remote sensors' capability of detecting shallow groundwater effect, we conclude that this effect can be sufficiently clear to be sensed if at least one of two conditions is met: high potential evaporation and big contrast in air temperature between day and night. Under these conditions, most day and night hours are suitable for shallow groundwater depth detection.

  6. Groundwater Governance in the United States: Common Priorities and Challenges.

    Science.gov (United States)

    Megdal, Sharon B; Gerlak, Andrea K; Varady, Robert G; Huang, Ling-Yee

    2015-01-01

    Groundwater is a critical component of the water supply for agriculture, urban areas, industry, and ecosystems, but managing it is a challenge because groundwater is difficult to map, quantify, and evaluate. Until recently, study and assessment of governance of this water resource has been largely neglected. A survey was developed to query state agency officials about the extent and scope of groundwater use, groundwater laws and regulations, and groundwater tools and strategies. Survey responses revealed key findings: states' legal frameworks for groundwater differ widely in recognizing the hydrologic connection between surface water and groundwater, the needs of groundwater-dependent ecosystems, and the protection of groundwater quality; states reported a range in capacity to enforce groundwater responsibilities; and states have also experienced substantial changes in groundwater governance in the past few decades. Overall, groundwater governance across the United States is fragmented. States nevertheless identified three common priorities for groundwater governance: water quality and contamination, conflicts between users, and declining groundwater levels. This survey represents an initial step in a broader, continuing effort to characterize groundwater governance practices in the United States.

  7. Assessing tsunami-induced groundwater salinization and its temporal change: a numerical modelling study on the Niijima Island, Japan

    Science.gov (United States)

    Liu, Jiaqi; Tokunaga, Tomochika

    2016-04-01

    Groundwater is vulnerable to many natural hazards, including tsunami. As reported after the 2004 Indian Ocean earthquake and the 2011 Great East Japan earthquake, the generated massive tsunami inundations resulted in unexpected groundwater salinization in coastal areas. Water supply was strongly disturbed due to the significantly elevated salinity in groundwater. Supplying fresh water is one of the prioritized concerns in the immediate aftermath of disaster, and during long-term post-disaster reconstruction as well. The aim of this study is to assess the impact of tsunami on coastal groundwater system and provide guidelines on managing water resources in post-tsunami period. We selected the study area as the Niijima Island, a tsunami-prone area in Japan, which is under the risk of being attacked by a devastated tsunami with its wave height up to 30 m. A three-dimension (3-D) numerical model of the groundwater system on the Niijima Island was developed by using the simulation code FEFLOW which can handle both density- dependent groundwater flow and saturated-unsaturated flow processes. The model was justified by the measured water table data obtained from the field work in July, 2015. By using this model, we investigated saltwater intrusion and aquifer recovery process under different tsunami scenarios. Modelling results showed that saltwater could fully saturate the vadose zone and come into contact with groundwater table in just 10 mins. The 0.6 km2 of inundation area introduced salt mass equivalent to approximately 9×104 t of NaCl into the vadose zone. After the retreat of tsunami waves, the remained saltwater in vadose zone continuously intruded into the groundwater and dramatically salinized the aquifer up to about 10,000 mg/L. In the worst tsunami scenario, it took more than 10 years for the polluted aquifer to be entirely recovered by natural rainfall. Given that the groundwater is the only freshwater source on the Niijima Island, we can provide suggestions

  8. Groundwater Remediation and Alternate Energy at White Sands Test Facility

    Science.gov (United States)

    Fischer, Holger

    2008-01-01

    White Sands Test Facility Core Capabilities: a) Remote Hazardous Testing of Reactive, Explosive, and Toxic Materials and Fluids; b) Hypergolic Fluids Materials and Systems Testing; c) Oxygen Materials and System Testing; d) Hypervelocity Impact Testing; e)Flight Hardware Processing; and e) Propulsion Testing. There is no impact to any drinking water well. Includes public wells and the NASA supply well. There is no public exposure. Groundwater is several hundred feet below ground. No air or surface water exposure. Plume is moving very slowly to the west. Plume Front Treatment system will stop this westward movement. NASA performs on-going monitoring. More than 200 wells and zones are routinely sampled. Approx. 850 samples are obtained monthly and analyzed for over 300 different hazardous chemicals.

  9. Nitrate isotopic composition and ancillary variables (land use, redox, excess N2, age, water isotopics) in California groundwater

    Science.gov (United States)

    Veale, Nathan; Moran, Jean; Visser, Ate; Singleton, Michael; Esser, Bradley

    2017-04-01

    Nitrate is a critical water quality issue in California, the United States and the world. Lawrence Livermore National Laboratory (LLNL) has compiled a large, unique database of California groundwater nitrate isotopic compositions (δ15N-NO3 and δ18O-NO3), acquired largely through more than a decade of coordination with the State of California Groundwater Ambient Monitoring and Assessment (GAMA) program. The water samples are predominantly from shallow aquifers accessed by domestic and monitoring wells. The database of >1,300 nitrate isotopic compositions includes a number of important ancillary parameters: DO, ORP and DOC (measured for 18% of samples); excess air and dissolved N2 (24%); water isotopic composition (δ18O-H2O and δD-H2O) (43%); and tritium/3He groundwater age (27%). Methods used at LLNL include sample preparation by the denitrifier method (for δ15N-NO3 and δ18O-NO3) and Isotope Ratio Mass Spectrometry with (δ15N-NO3 and δ18O-NO3 and δ18O-H2O and δD-H2O), Noble Gas Mass Spectrometry (NGMS; for excess air and groundwater age), and Membrane Inlet Mass Spectrometry (MIMS; for major dissolved gases and excess N2). Redox indicators (DO, ORP and DOC) in conjunction with excess N2, groundwater age, and nitrate isotopic composition are used to assess the presence or absence, and potentially the rate of, saturated-zone denitrification. Comparison of δ18O-NO3 to δ18O-H2O isotopic composition is used to distinguish synthetic nitrate from nitrification of reduced forms of nitrogen as a source of groundwater nitrate. Groundwater age is used to discern timing and temporal trends in groundwater nitrate isotopic composition. The relationship of nitrate isotopic composition to ancillary parameters (redox, excess N2, water isotopic composition and groundwater age) is explored, along with its relationship to well location, screened interval, and land use, with a focus on the extent of saturated-zone denitrification and the significance of synthetic nitrate as

  10. Groundwater Recharge Rates and Surface Runoff Response to Land Use and Land Cover Changes in Semi-arid Environments

    Science.gov (United States)

    Owuor, Steven; Butterbach-Bahl, Klaus; Guzha, Alphonce; Rufino, Mariana; Pelster, David; Díaz-Pinés, Eugenio; Breuer, Lutz; Merbold, Lutz

    2017-04-01

    Conclusive evidence and understanding of the effects of land use and land cover (LULC) on both groundwater recharge and surface runoff is critical for effective management of water resources in semi-arid region as those heavily depend on groundwater resources. However, there is limited quantitative evidence on how changes to LULC in semi-arid tropical and subtropical regions affect the subsurface components of the hydrologic cycle, particularly groundwater recharge. In this study, we reviewed a total of 27 studies (2 modelling and 25 experimental), which reported on pre- and post-land use change groundwater recharge or surface runoff magnitude, and thus allowed to quantify the response of groundwater recharge rates and runoff to LULC. Restoration of bare land induces a decrease in groundwater recharge from 42 % of precipitation to between 6 and 12 % depending on the final LULC. If forests are cleared for rangelands, groundwater recharge increases by 7.8 ± 12.6 %, while conversion to cropland or grassland results in increases of 3.4 ± 2.5 and 4.4 ± 3.3 %, respectively. Rehabilitation of bare land to cropland results in surface runoff reductions of between 5.2 and 7.3 %. The conversion of forest vegetation to managed LULC shows an increase in surface runoff from 1 to 14.1 % depending on the final LULC. Surface runoff is reduced from 2.5 to 1.1 % when grassland is converted to forest vegetation. While there is general consistency in the results from the selected case studies, we conclude that there are few experimental studies that have been conducted in tropical and subtropical semi-arid regions, despite that many people rely heavily on groundwater for their livelihoods. Therefore, there is an urgent need to increase the body of quantitative evidence given the pressure of growing human population and climate change on water resources in the region.

  11. Spatial and Temporal Variability in Nitrate Concentration below the Root Zone in an Almond Orchard and its Implications for Potential Groundwater Contamination

    Science.gov (United States)

    Baram, S.; Couvreur, V.

    2015-12-01

    Spatial and Temporal Variability in Nitrate Concentration below the Root Zone in an Almond Orchard and its Implications for Potential Groundwater Contamination S. Baram1, M. Read1, D. Smart2, T. Harter1, J Hopmans11Department of Land, Air & Water Resources University of California Davis 2Department of Viticulture and Enology University of California Davis Estimates of water and fertilizer losses below the root zone of nitrogen (N) intensive agricultural orchard crops are major concern in groundwater protection. However, microscopic and macroscopic heterogeneity in unsaturated soils make accurate loss estimates very challenging. In this study we aimed to examine field scale variability in nitrate (NO3-) losses below the root zone (>250cm) of a 15 years old almond orchard in Madera county California. Based on a soil variability survey, tensiometers and solution samplers were installed at 17 locations around the 40 acre orchard. The hydraulic potential and the NO3- concentrations were monitored over two growing seasons. Nitrate concentrations varied spatially and temporarily, and ranged from below to more than 30 times higher than the drinking water contamination standard of >10 mg NO3--N L-1. Principal component analysis of the relations between the NO3- concentration, presence of a hard pan in the subsurface, its depth and thickness, and the fertigation and irrigation events indicated that none of these factors explained the observed variability in pore-water NO3- concentrations, with hard pan being the most dominant factor. Throughout the irrigation season minimal leaching was observed, yet post-harvest and preseason flooding events led to deep drainage. Due to the high spatial and temporal variability in the NO3- concentration and the potential for deep drainage following a wet winter or flooding event we conclude that the most efficient way to protect ground water is by transitioning to high frequency low nitrogen fertigation which would retain NO3-in the active

  12. Use of Interface Treatment to Reduce Emissions from Residuals in Lower Permeability Zones to Groundwater flowing Through More Permeable Zones (Invited)

    Science.gov (United States)

    Johnson, P.; Cavanagh, B.; Clifton, L.; Daniels, E.; Dahlen, P.

    2013-12-01

    Many soil and groundwater remediation technologies rely on fluid flow for contaminant extraction or reactant delivery (e.g., soil vapor extraction, pump and treat, in situ chemical oxidation, air sparging, enhanced bioremediation). Given that most unconsolidated and consolidated settings have permeability contrasts, the outcome is often preferential treatment of more permeable zones and ineffective treatment of the lower permeability zones. When this happens, post-treatment contaminant emissions from low permeability zone residuals can cause unacceptable long-term impacts to groundwater in the transmissive zones. As complete remediation of the impacted lower permeability zones may not be practicable with conventional technologies, one might explore options that lead to reduction of the contaminant emissions to acceptable levels, rather than full remediation of the lower permeability layers. This could be accomplished either by creating a sustained emission reaction/attenuation zone at the high-low permeability interface, or by creating a clean soil zone extending sufficiently far into the lower permeability layer to cause the necessary reduction in contaminant concentration gradient and diffusive emission. These options are explored in proof-of-concept laboratory-scale physical model experiments. The physical models are prepared with two layers of contrasting permeability and either dissolved matrix storage or nonaqueous phase liquid (NAPL) in the lower permeability layer. A dissolved oxidant is then delivered to the interface via flow across the higher permeability layer and changes in contaminant emissions from the low permeability zone are monitored before, during, and after oxidant delivery. The use of three oxidants (dissolved oxygen, hydrogen peroxide and sodium persulfate) for treatment of emissions from petroleum hydrocarbon residuals is examined.

  13. Monitoring and modelling terbuthylazine and desethyl-terbuthylazine in groundwater.

    Science.gov (United States)

    Fait, G.; Balderacchi, M.; Ferrari, F.; Capri, E.; Trevisan, M.

    2009-04-01

    Protection of ground and surface water quality is critical to human health and environmental quality, as well as economic viability. The presence of contaminants in groundwater is a common phenomenon and derives from many anthropogenic activities. Among these activities most likely to pollute water resources are the use of fertilizers, pesticides, application of livestock, poultry manure, and urban sludge. Therefore, agriculture results to be a significant contributor to diffuse and point sources of groundwater contamination. A study was carried out from April 2005 until December 2007 in order to monitor the concentrations of the herbicide terbuthylazine and one of its metabolite, desethyl-terbuthylazine in shallow groundwater. Terbuthylazine is a widely used herbicide for pre-emergence and post-emergence weed control in several crops. The monitoring study was performed in different Italian areas representative of maize crop. These areas resulted to be in the north of Italy, in the Po Valley area. Inside these representative areas a total of eleven farms were identified; each farm had a plot extended for about 10 hectares, cultivated with maize according to normal agricultural practices, with slope not exceeding 5%, uniform direction of groundwater flow, absence of superficial water bodies. In order to sample groundwater, each plot was equipped with four couples of piezometers. Groundwater samplings were carried out every two months. The results showed that the concentrations of both compounds were in general low, except in a couple of sites, and especially in June and August, the months which follow the treatment, and in October and December, usually rainy months. In general metabolite concentrations were higher than the parent compound. On one hand a monitoring approach is helpful in order to understand the behaviour of a compound in real conditions; however, on the other hand it gives only an instant picture of the present situation without any prevision about

  14. South-East Iowa Groundwater Vulnerability Regions

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The regions on this map represent areas with similar hydro- geologic characteristics thought to represent similar potentials for contamination of groundwater and/or...

  15. Potential Health Effects from Groundwater Pollution.

    Science.gov (United States)

    Goyer, Robert A.

    1985-01-01

    Discusses the growing awareness of potential toxicological effects of synthetic organic chemicals contaminating groundwater. Problems concerning pesticides, chlorination, epidemiologic studies, cancer, nephrotoxicity, and considerations of risk are addressed. Additional research in this area is advocated. (DH)

  16. Hydrogeochemical and isotopic characterization of the groundwater ...

    African Journals Online (AJOL)

    POSTE7

    : ... is also affected by the relief, while the southward shift of the isohyets .... Solids (TDS) were calculated by adding the main ionic species ... (Davis and De Wiest, 1966; Freeze and Cherry, 1979). ... depression point of groundwater discharge.

  17. Groundwater pollution: are we monitoring appropriate parameters?

    CSIR Research Space (South Africa)

    Tredoux, G

    2004-01-01

    Full Text Available . In the literature, divergent approaches have identified various sets of pollutants and pollution indicators. This paper discusses international and local trends in groundwater monitoring for baseline studies and on-going pollution detection monitoring for a variety...

  18. North-West Iowa Groundwater Vulnerability Regions

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The regions on this map represent areas with similar hydro-geologic characteristics thought to represent similar potentials for contamination of groundwater and/or...

  19. North-East Iowa Groundwater Vulnerability Regions

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The regions on this map represent areas with similar hydro-geologic characteristics thought to represent similar potentials for contamination of groundwater and/or...

  20. Effect of Groundwater Abstraction on Fen Ecosystems

    DEFF Research Database (Denmark)

    Johansen, Ole; Pedersen, Morten Lauge; Jensen, Jacob Birk

    2011-01-01

    Quantifying the effects of groundwater abstraction on fen ecosystems located in discharge areas can be complicated. The water level in fens is close to the terrain surface most of the year and it is controlled by a relatively constant groundwater exfiltration. It is difficult to measure...... the exfiltration fluxes and thus water level data is typically used to evaluate if the ecosystem is affected. The paper presents collected data and analysis from a case study, where the hydrological effect of groundwater abstraction on rich fens and springs in a Danish river valley has been studied. The natural...... within a distance of 1.5 km to a planned well field. In the river valley the interaction between groundwater and surface water is strongly affected by low permeable sediments. These sediments reduce the direct discharge to the river and have a large impact on the functioning and presence of the rich fen...

  1. Isolation of haloorganic groundwater humic substances

    DEFF Research Database (Denmark)

    Krog, M.; Grøn, C.

    1995-01-01

    Humic substances were isolated from groundwater according to a revised method designed to avoid organohalogen artefacts. The prepared humic substances exhibited lower halogen contents than humic substances isolated according to the conventionally used method. Excessive oxidation or hydrolysis...

  2. Science, society, and the coastal groundwater squeeze

    Science.gov (United States)

    Michael, Holly A.; Post, Vincent E. A.; Wilson, Alicia M.; Werner, Adrian D.

    2017-04-01

    Coastal zones encompass the complex interface between land and sea. Understanding how water and solutes move within and across this interface is essential for managing resources for society. The increasingly dense human occupation of coastal zones disrupts natural groundwater flow patterns and degrades freshwater resources by both overuse and pollution. This pressure results in a "coastal groundwater squeeze," where the thin veneers of potable freshwater are threatened by contaminant sources at the land surface and saline groundwater at depth. Scientific advances in the field of coastal hydrogeology have enabled responsible management of water resources and protection of important ecosystems. To address the problems of the future, we must continue to make scientific advances, and groundwater hydrology needs to be firmly embedded in integrated coastal zone management. This will require interdisciplinary scientific collaboration, open communication between scientists and the public, and strong partnerships with policymakers.

  3. South-West Iowa Groundwater Vulnerability Regions

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The regions on this map represent areas with similar hydro- geologic characteristics thought to represent similar potentials for contamination of groundwater and/or...

  4. Assessment of Physicochemical Characteristics of Groundwater ...

    African Journals Online (AJOL)

    Assessment of Physicochemical Characteristics of Groundwater Quality used for Drinking ... Key Words: Water Quality, Water Quality Index, EIA, Health, Diseases, Firozabad City. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  5. Analysing Groundwater Using the 13C Isotope

    Science.gov (United States)

    Awad, Sadek

    The stable isotope of the carbon atom (13C) give information about the type of the mineralisation of the groundwater existing during the water seepage and about the recharge conditions of the groundwater. The concentration of the CO2(aq.) dissolved during the infiltration of the water through the soil's layers has an effect on the mineralisation of this water. The type of the photosynthesis's cycle (C-3 or C-4 carbon cycle) can have a very important role to determine the conditions (closed or open system) of the mineralisation of groundwater. The isotope 13C of the dissolved CO2 in water give us a certain information about the origin and the area of pollution of water. The proportion of the biogenic carbon and its percentage in the mineralisation of groundwater is determined by using the isotope 13C.

  6. Arsenic Speciation in Groundwater: Role of Thioanions

    Science.gov (United States)

    The behavior of arsenic in groundwater environments is fundamentally linked to its speciation. Understanding arsenic speciation is important because chemical speciation impacts reactivity, bioavailability, toxicity, and transport and fate processes. In aerobic environments arsen...

  7. Hydro geophysical Investigation for Groundwater Development at ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Keywords: basement complex, electrical sounding, groundwater, exploration, aquifers. Fresh water is a .... underscores the reliability of the analysis tool for this type of work. Latitude .... Jatau, B.S., Patrick N.O., Baba A., Fadele S.I. (Jan.

  8. Building groundwater modeling capacity in Mongolia

    Science.gov (United States)

    Valder, Joshua F.; Carter, Janet M.; Anderson, Mark T.; Davis, Kyle W.; Haynes, Michelle A.; Dorjsuren Dechinlhundev,

    2016-06-16

    Ulaanbaatar, the capital city of Mongolia (fig. 1), is dependent on groundwater for its municipal and industrial water supply. The population of Mongolia is about 3 million people, with about one-half the population residing in or near Ulaanbaatar (World Population Review, 2016). Groundwater is drawn from a network of shallow wells in an alluvial aquifer along the Tuul River. Evidence indicates that current water use may not be sustainable from existing water sources, especially when factoring the projected water demand from a rapidly growing urban population (Ministry of Environment and Green Development, 2013). In response, the Government of Mongolia Ministry of Environment, Green Development, and Tourism (MEGDT) and the Freshwater Institute, Mongolia, requested technical assistance on groundwater modeling through the U.S. Army Corps of Engineers (USACE) to the U.S. Geological Survey (USGS). Scientists from the USGS and USACE provided two workshops in 2015 to Mongolian hydrology experts on basic principles of groundwater modeling using the USGS groundwater modeling program MODFLOW-2005 (Harbaugh, 2005). The purpose of the workshops was to bring together representatives from the Government of Mongolia, local universities, technical experts, and other key stakeholders to build in-country capacity in hydrogeology and groundwater modeling.A preliminary steady-state groundwater-flow model was developed as part of the workshops to demonstrate groundwater modeling techniques to simulate groundwater conditions in alluvial deposits along the Tuul River in the vicinity of Ulaanbaatar. ModelMuse (Winston, 2009) was used as the graphical user interface for MODFLOW for training purposes during the workshops. Basic and advanced groundwater modeling concepts included in the workshops were groundwater principles; estimating hydraulic properties; developing model grids, data sets, and MODFLOW input files; and viewing and evaluating MODFLOW output files. A key to success was

  9. Oxygen and Hydrogen Isotopes of Waters in the Ordos Basin,China: Implications for Recharge of Groundwater in the North of Cretaceous Groundwater Basin

    Institute of Scientific and Technical Information of China (English)

    YANG Yuncheng; SHEN Zhaoli; WENG Dongguang; HOU Guangcai; ZHAO Zhenhong; WANG Dong; PANG Zhonghe

    2009-01-01

    Hundreds of precipitation samples collected from meteorological stations in the Ordos Basin from January 1988 to December 2005 were used to set up a local meteoric water line and to calculate weighted average isotopic compositions of modern precipitation.Oxygen and hydrogen isotopes, with and gradually decrease in summer and fall,illustrating that the seasonal effect is considerable.They also show that the isotopic difference between south portion and north portion of the Ordos Basin are not obvious.and the isotope in the middle portion iS normally depleted.The isotope compositions of 32 samples collected from shallow groundwater(less than a depth of 150 m)in desert plateau range from for JD.Most of them are identical with modern precipitation.The isotope compositions of 22 middle and deep groundwaters(greater than a depth of 275 m)fall in ranges from-11.6‰to-8.8‰with an average of-10.2‰ for £18O and from-89‰ to-63‰ with an average of-76‰ for £D.The average values are significantly less than those of modern precipitation,illustrating that the middle and deep groundwaters were recharged at comparatively lower air temperatures.Primary analysis of 14C shows that the recharge of the middle and deep groundwaters started at late Pleistocene.The isotopes of 13 lake water samples collected from eight lakes define a local evaporation trend,with a relatively flat slope of 3.77,and show that the lake waters were mainly fed by modern precipitation and shallow groundwater.

  10. SEAWAT: A Computer Program for Simulation of Variable-Density Groundwater Flow and Multi-Species Solute and Heat Transport

    Science.gov (United States)

    Langevin, Christian D.

    2009-01-01

    SEAWAT is a MODFLOW-based computer program designed to simulate variable-density groundwater flow coupled with multi-species solute and heat transport. The program has been used for a wide variety of groundwater studies including saltwater intrusion in coastal aquifers, aquifer storage and recovery in brackish limestone aquifers, and brine migration within continental aquifers. SEAWAT is relatively easy to apply because it uses the familiar MODFLOW structure. Thus, most commonly used pre- and post-processors can be used to create datasets and visualize results. SEAWAT is a public domain computer program distributed free of charge by the U.S. Geological Survey.

  11. Dissolved helium and TDS in groundwater from Bhavnagar in Gujarat: Unrelated to seismic events between August 2000 and January 2001

    Indian Academy of Sciences (India)

    S K Gupta; R D Deshpande

    2003-03-01

    Temporal variations have been observed in both dissolved helium and TDS in the form of increase in basaltic and decrease in alluvial aquifers. The increase in basaltic aquifers has been explained by enhanced pumping of old groundwater with relatively higher concentration of dissolved helium and salt, whereas the decrease in alluvial aquifers has been explained by dilution from the post monsoon groundwater recharge. Therefore, the observed temporal variations cannot be ascribed to the contemporary enhanced seismic activity in this region since August-September 2000.

  12. POSIVA groundwater flow measuring techniques

    Energy Technology Data Exchange (ETDEWEB)

    Oehberg, A. [Saanio and Riekkola Consulting Engineers, Helsinki (Finland); Rouhiainen, P. [PRG-Tec Oy (Finland)

    2000-08-01

    Posiva Oy has carried out site characterisation for the final disposal of spent nuclear fuel in Finland since 1987. To meet the demanding needs to measure the hydraulic parameters in bedrock Posiva launched development of new flowmeter techniques including measuring methods and equipment in co-operation with PRG-Tec Oy. The techniques have been tested and used in the ongoing site investigations in Finland, in the underground Hard Rock Laboratory (HRL) at Aespoe in Sweden and in URL in Canada. The new methods are called difference flow and transverse flow methods. The difference flow method includes two modes, normal and detailed flow logging methods. In the normal mode the flow rate measurement is based on thermal pulse and thermal dilution methods, in the detailed logging mode only on thermal dilution method. The measuring ranges for flow rate with thermal pulse and dilution methods are 0.1-10 ml/min and 2-5000 ml/min, respectively. The difference flow method(normal mode) for small flows (0.1-10 ml/min) is based on measuring the pulse transit time and direction of a thermal pulse in the sensor. For high flows (2-5000 ml/min) the method is based on thermal dilution rate of a sensor. Direction is measured with monitoring thermistors. Inflow or outflow in the test interval is created due to natural or by pumping induced differences between heads in the borehole water and groundwater around the borehole. The single point resistance (and the temperature of borehole water) measurement is carried out simultaneously with the difference flow measurements, both in normal and detailed flow logging modes, while the tool is moving. The result is utilised for checking the exact depth of the tool. As the result a continuous log is obtained from which single fractures can be detected. The transverse flowmeter is able to measure the groundwater flow across a borehole. A special packer system guides the flow through the flow sensors. Four inflatable seals between conventional

  13. Impact of oil on groundwater chemical composition

    Science.gov (United States)

    Brakorenko, N. N.

    2015-11-01

    The objective of the paper is to characterize the chemical composition of groundwater samples from the monitoring wells drilled in the petrol station areas within the vicinity of Tomsk. The level of contamination has increased since many macro - and microcomponent concentrations (such as petroleum products, chlorine, sulphates, carbon dioxide and lead, etc.) in groundwater samples of the present study is higher than that in previous period samples.

  14. Selective sorption of technetium from groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G. [Oak Ridge National Lab., TN (United States)

    1996-10-01

    The purpose of this project is to develop an anion exchange resin that will selectively remove the radionuclide technetium, in the form of the pertechnetate anion TcO{sub 4}{sup -}, from groundwater, leaving behind other interfering anions. A resin bed of this material will be used either as part of a coupled treatment-recirculation system for the in situ remediation of groundwater contaminated with technetium or in a once-through treatment scheme.

  15. Intercomparison of Rn-222 determination from groundwater

    DEFF Research Database (Denmark)

    Vesterbacka, P.; Pettersson, H.; Hanste, U.-M.;

    2010-01-01

    An intercomparison exercise on Rn-222 determination in groundwater was organized between eight Nordic laboratories. The individual laboratory results were in most cases within 20% of the median value and within reported uncertainties. Considering the particular difficulties in preparing, transpor......An intercomparison exercise on Rn-222 determination in groundwater was organized between eight Nordic laboratories. The individual laboratory results were in most cases within 20% of the median value and within reported uncertainties. Considering the particular difficulties in preparing...

  16. Development and Testing of Active Groundwater Samplers

    DEFF Research Database (Denmark)

    Nilsson, Bertel; Jakobsen, Rasmus; Andersen, Lars Jørgen

    1995-01-01

    Active groundwater sampling techniques are methods where the aquifer is flushed by pumping. The methods developed and tested represent non-dedicated methods for use in existing water wells. This paper describes two different sampling techniques: the Separation Pumping Technique (SP) and the Packer...... on numerical modelling and controlled laboratory experiments. Active groundwater sampling techniques can be used for remedial pumping optimization and in obtaining hydraulic data and represent a fast operational and reliable sampling tool, also under heterogeneous and low permeability conditions....

  17. Evolution of Unsteady Groundwater Flow Systems

    Science.gov (United States)

    Liang, Xing; Jin, Menggui; Niu, Hong

    2016-04-01

    Natural groundwater flow is usually transient, especially in long time scale. A theoretical approach on unsteady groundwater flow systems was adopted to highlight some of the knowledge gaps in the evolution of groundwater flow systems. The specific consideration was focused on evolution of groundwater flow systems from unsteady to steady under natural and mining conditions. Two analytical solutions were developed, using segregation variable method to calculate the hydraulic head under steady and unsteady flow conditions. The impact of anisotropy ratio, hydraulic conductivity (K) and specific yield (μs) on the flow patterns were analyzed. The results showed that the area of the equal velocity region increased and the penetrating depth of the flow system decreased while the anisotropy ratio (ɛ = °Kx-/Kz--) increased. Stagnant zones were found in the flow field where the directions of streamlines were opposite. These stagnant zones moved up when the horizontal hydraulic conductivity increased. The results of the study on transient flow indicated a positive impact on hydraulic head with an increase of hydraulic conductivity, while a negative effect on hydraulic head was observed when the specific yield was enhanced. An unsteady numerical model of groundwater flow systems with annual periodic recharge was developed using MODFLOW. It was observed that the transient groundwater flow patterns were different from that developed in the steady flow under the same recharge intensity. The water table fluctuated when the recharge intensity altered. The monitoring of hydraulic head and concentration migration revealed that the unsteady recharge affected the shallow local flow system more than the deep regional flow system. The groundwater flow systems fluctuated with the action of one or more pumping wells. The comparison of steady and unsteady groundwater flow observation indicated that the unsteady flow patterns cannot be simulated by the steady model when the condition

  18. Arsenic geochemistry of groundwater in Southeast Asia.

    Science.gov (United States)

    Kim, Kyoung-Woong; Chanpiwat, Penradee; Hanh, Hoang Thi; Phan, Kongkea; Sthiannopkao, Suthipong

    2011-12-01

    The occurrence of high concentrations of arsenic in the groundwater of the Southeast Asia region has received much attention in the past decade. This study presents an overview of the arsenic contamination problems in Vietnam, Cambodia, Lao People's Democratic Republic and Thailand. Most groundwater used as a source of drinking water in rural areas has been found to be contaminated with arsenic exceeding the WHO drinking water guideline of 10 μg·L(-1). With the exception of Thailand, groundwater was found to be contaminated with naturally occurring arsenic in the region. Interestingly, high arsenic concentrations (> 10 μg·L(-1)) were generally found in the floodplain areas located along the Mekong River. The source of elevated arsenic concentrations in groundwater is thought to be the release of arsenic from river sediments under highly reducing conditions. In Thailand, arsenic has never been found naturally in groundwater, but originates from tin mining activities. More than 10 million residents in Southeast Asia are estimated to be at risk from consuming arsenic-contaminated groundwater. In Southeast Asia, groundwater has been found to be a significant source of daily inorganic arsenic intake in humans. A positive correlation between groundwater arsenic concentration and arsenic concentration in human hair has been observed in Cambodia and Vietnam. A substantial knowledge gap exists between the epidemiology of arsenicosis and its impact on human health. More collaborative studies particularly on the scope of public health and its epidemiology are needed to conduct to fulfill the knowledge gaps of As as well as to enhance the operational responses to As issue in Southeast Asian countries.

  19. Mixed Waste Management Facility Groundwater Monitoring Report

    Energy Technology Data Exchange (ETDEWEB)

    Chase, J.

    1998-03-01

    During fourth quarter 1997, eleven constituents exceeded final Primary Drinking Water Standards (PDWS) in groundwater samples from downgradient monitoring wells at the Mixed Waste Management Facility. No constituents exceeded final PDWS in samples from upgradient monitoring wells. As in previous quarters, tritium and trichloroethylene were the most widespread elevated constituents. The groundwater flow directions and rates in the three hydrostratigraphic units were similar to those of previous quarters.

  20. Groundwater sustainability in Asian Mega city

    Science.gov (United States)

    Taniguchi, M.

    2009-12-01

    Population increased in many Asian coastal cities, and increased demand of groundwater as water resources caused many subsurface environments. Subsurface environmental problems such as land subsidence due to excessive pumping, groundwater contamination and subsurface thermal anomaly, have occurred repeatedly in Asian mega cities with a time lag depending on the development stage of urbanization. This study focus on four subjects; urban, water, heat, and material in subsurface environment, and intensive field observations and data collections had been made in the basins including Tokyo, Osaka, Bangkok, Jakarta, Manila, Seoul, and Taipei. The new methods for evaluating the changes in groundwater storage by gravimeter measurements in situ and Satellite GRACE, and residence time evaluation by 85Kr and CFCs, have been developed in this study. The combined effects of heat island and global warming from subsurface temperature in Asian mega cities evaluated the magnitude and timing of the urbanization which were preserved in subsurface thermal environment. The effects of law/institution on change in reliable water resources between groundwater and surface water, have been also investigated. The groundwater is “private water”, on the other hand, the surface water is “public water”. Regulation of groundwater pumping due to serious land subsidence did not work without alternative water resources, and the price of water is another major factor for the change in reliable water resources between groundwater and surface water. Land use/cover changes at three ages (1940’s, 1970’s and 2000’s) have been analyzed based on GIS with 0.5 km grid at seven targeted cities. The development of integrated indicators based on GIS for understanding the relationship between human activities and subsurface environment have been made in this study. Finally, we address the sustainable use of groundwater and subsurface environments for better future development and human well-being.

  1. Sustainable Remediation for Enhanced NAPL Recovery from Groundwater

    Science.gov (United States)

    Javaher, M.

    2012-12-01

    Sustainable remediation relates to the achievement of balance between environmental, social, and economic elements throughout the remedial lifecycle. A significant contributor to this balance is the use of green and sustainable technologies which minimize environmental impacts, while maximizing social and economic benefits of remedial implementation. To this end, a patented mobile vapor energy generation (VEG) technology has been developed targeting variable applications, including onsite soil remediation for unrestricted reuse and enhanced non-aqueous phase liquid (NAPL) recover at the water table. At the core of the mobile VEG technology is a compact, high efficiency vapor generator, which utilizes recycled water and propane within an entirely enclosed system to generate steam as high as 1100°F. Operating within a fully enclosed system and capturing all heat that is generated within this portable system, the VEG technology eliminates all emissions to the atmosphere and yields an undetected carbon footprint with resulting carbon dioxide concentrations that are below ambient levels. Introduction of the steam to the subsurface via existing wells results in a desired change in the NAPL viscosity and the interfacial tension at the soil, water, NAPL interface; in turn, this results in mobilization and capture of the otherwise trapped, weathered NAPL. Approved by the California Air Resources Control Board (and underlying Air Quality Management Districts) and applied in California's San Joaquin Valley, in-well heating of NAPLs trapped at the water table using the VEG technology has proven as effective as electrical resistivity heating (ERH) in changing the viscosity of and mobilizing NAPLs in groundwater in support of recovery, but has achieved these results while minimizing the remedial carbon footprint by 90%, reducing energy use by 99%, and reducing remedial costs by more than 95%. NAPL recovery using VEG has also allowed for completion of source removal historically

  2. Groundwater flow and transport modelling during the temperate period for the SR-Can assessment. Forsmark area - version 1.2

    Energy Technology Data Exchange (ETDEWEB)

    Hartley, Lee; Hoch, Andrew; Jackson, Peter; Joyce, Steve; McCarthy, Rachel; Rodwell, William; Swift, Ben [Serco Assurance, Harwell (United Kingdom); Marsic, Niko [Kemakta Konsult AB, Stockholm (Sweden)

    2006-12-15

    The focus of the study described in this report has been to perform numerical simulations of the geosphere from post-closure and throughout the temperate period up until the beginning of the next permafrost period around 9,000 AD. Together with providing quantitative results for the immediate temperate period following post-closure, these results are also intended to give a qualitative indication of the evolution of the groundwater system during future temperate periods within an ongoing cycle of glacial/inter-glacial events. Additional calculations were performed to assess the impact of the effects of gas and heat generation in the repository on groundwater flow.

  3. Remediation Technology for Contaminated Groundwater

    Science.gov (United States)

    Bioremediation is the most commonly selected technology for remediation of ground water at Superfund sites in the USA. The next most common technology is Chemical treatment, followed by Air Sparging, and followed by Permeable Reactive Barriers. This presentation reviews the the...

  4. Groundwater hydrology” is redundant

    Science.gov (United States)

    While in the Netherlands a few months ago, I mentioned “groundwater hydrology” to a very well-educated, very literary, and non-hydrologic old friend. She shuddered and told me in no uncertain words that this was a horrible term, completely redundant like a round circle, or as the linguists call it, a pleonasm. This is, of course, because hydrology already means water science (from the Greek words udor, or hydor for water, and logos for science), so that groundwater hydrology really stands for groundwater water science, and surface water hydrology for surface water science.These are pleonasms of the first kind and insults to any language purist, which all of us should strive to be! So I propose that henceforth groundwater hydrology be called subterranean hydrology. Other possibilities would be subsurface hydrology, but this sounds too shallow, or underground hydrology, which, however, could give the impression of some clandestine activity. Besides, subterranean hydrology would be in keeping with the words for groundwater in Latin-based languages (eau souterrain in French, acqua sotierranea in Italian, and aguas subterraneas in Spanish). Also, subterranean hydrology includes the vadose zone, which, of course, groundwater hydrology as such does not. Surface water hydrology would simply be called surface hydrology, and anything above that atmospheric hydrology.

  5. Groundwater depletion embedded in international food trade

    Science.gov (United States)

    Dalin, Carole; Wada, Yoshihide; Kastner, Thomas; Puma, Michael J.

    2017-03-01

    Recent hydrological modelling and Earth observations have located and quantified alarming rates of groundwater depletion worldwide. This depletion is primarily due to water withdrawals for irrigation, but its connection with the main driver of irrigation, global food consumption, has not yet been explored. Here we show that approximately eleven per cent of non-renewable groundwater use for irrigation is embedded in international food trade, of which two-thirds are exported by Pakistan, the USA and India alone. Our quantification of groundwater depletion embedded in the world’s food trade is based on a combination of global, crop-specific estimates of non-renewable groundwater abstraction and international food trade data. A vast majority of the world’s population lives in countries sourcing nearly all their staple crop imports from partners who deplete groundwater to produce these crops, highlighting risks for global food and water security. Some countries, such as the USA, Mexico, Iran and China, are particularly exposed to these risks because they both produce and import food irrigated from rapidly depleting aquifers. Our results could help to improve the sustainability of global food production and groundwater resource management by identifying priority regions and agricultural products at risk as well as the end consumers of these products.

  6. Natural Biological Attenuation of Benzene in Groundwater

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Benzene has been found in subsurface unsaturated soil and groundwater beneath a petro-chemical plant. Although the groundwater contained several mg/L of benzene in the area immediately beneath the source, benzene was not detected in monitoring wells approximately 800m down stream. All kinds of physical processes such as adsorption and advection/dispersion are considered to account for the observed attenuation. The results indicated that the attenuation was primarily due to natural biological processes occurring within the aquifer. The evidence for the natural bioremediation of benzene from the groundwater included: (1) analysis of groundwater chemistry, (2) laboratory studies demonstrating benzene biodegradation in aquifer samples, and (3) computer simulations examining benzene transport. Laboratory experiments indicated that for conditions similar to those in the plume, the aerobic degradation of benzene by the naturally occurring microorganisms in the polluted groundwater samples was quite rapid with a half-life time of from 5 to 15 days. In situ analyses indicated the level of dissolved oxygen in the groundwater was over 2mg/L. Thus, oxygen should not limit the biodegradation. In fact, the benzene was also shown to degrade under anaerobic conditions. The results from the modeling simulations indicate that biodegradation is the dominant process influencing attenuation of the benzene.

  7. Future research needs involving pathogens in groundwater

    Science.gov (United States)

    Bradford, Scott A.; Harvey, Ronald W.

    2017-01-01

    Contamination of groundwater by enteric pathogens has commonly been associated with disease outbreaks. Proper management and treatment of pathogen sources are important prerequisites for preventing groundwater contamination. However, non-point sources of pathogen contamination are frequently difficult to identify, and existing approaches for pathogen detection are costly and only provide semi-quantitative information. Microbial indicators that are readily quantified often do not correlate with the presence of pathogens. Pathogens of emerging concern and increasing detections of antibiotic resistance among bacterial pathogens in groundwater are topics of growing concern. Adequate removal of pathogens during soil passage is therefore critical for safe groundwater extraction. Processes that enhance pathogen transport (e.g., high velocity zones and preferential flow) and diminish pathogen removal (e.g., reversible retention and enhanced survival) are of special concern because they increase the risk of groundwater contamination, but are still incompletely understood. Improved theory and modeling tools are needed to analyze experimental data, test hypotheses, understand coupled processes and controlling mechanisms, predict spatial and/or temporal variability in model parameters and uncertainty in pathogen concentrations, assess risk, and develop mitigation and best management approaches to protect groundwater.

  8. Future research needs involving pathogens in groundwater

    Science.gov (United States)

    Bradford, Scott A.; Harvey, Ronald W.

    2016-12-01

    Contamination of groundwater by enteric pathogens has commonly been associated with disease outbreaks. Proper management and treatment of pathogen sources are important prerequisites for preventing groundwater contamination. However, non-point sources of pathogen contamination are frequently difficult to identify, and existing approaches for pathogen detection are costly and only provide semi-quantitative information. Microbial indicators that are readily quantified often do not correlate with the presence of pathogens. Pathogens of emerging concern and increasing detections of antibiotic resistance among bacterial pathogens in groundwater are topics of growing concern. Adequate removal of pathogens during soil passage is therefore critical for safe groundwater extraction. Processes that enhance pathogen transport (e.g., high velocity zones and preferential flow) and diminish pathogen removal (e.g., reversible retention and enhanced survival) are of special concern because they increase the risk of groundwater contamination, but are still incompletely understood. Improved theory and modeling tools are needed to analyze experimental data, test hypotheses, understand coupled processes and controlling mechanisms, predict spatial and/or temporal variability in model parameters and uncertainty in pathogen concentrations, assess risk, and develop mitigation and best management approaches to protect groundwater.

  9. Groundwater management institutions to protect riparian habitat

    Science.gov (United States)

    Orr, Patricia; Colby, Bonnie

    2004-12-01

    Groundwater pumping affects riparian habitat when it causes the water table to drop beyond the reach of riparian plants. Riparian habitat provides services that are not directly traded in markets, as is the case with many environmental amenities. There is no direct market where one may buy or sell the mix of services provided by a riparian corridor. The objective of this article is to review groundwater management mechanisms and assess their strengths and weaknesses for preserving the ecological integrity of riparian areas threatened by groundwater pumping. Policy instruments available to those concerned with the effects of groundwater pumping on riparian areas fall into three broad categories: (1) command and control (CAC), (2) incentive-based economic instruments, and (3) cooperative/suasive strategies. The case of the San Pedro River illustrates multiple and overlapping strategies applied in an ongoing attempt to reverse accumulating damage to a riparian ecosystem. Policy makers in the United States can choose among a broad menu of policy options to protect riparian habitat from groundwater pumping. They can capitalize on the clarity of command-and-control strategies, the flexibility and less obtrusive nature of incentive-based economic strategies, and the benefits that collaborative efforts can bring in the form of mutual consideration. While collaborative problem solving and market-based instruments are important policy tools, experience indicates that a well-formulated regulatory structure to limit regional groundwater pumping is an essential component of an effective riparian protection strategy.

  10. Future research needs involving pathogens in groundwater

    Science.gov (United States)

    Bradford, Scott A.; Harvey, Ronald W.

    2017-06-01

    Contamination of groundwater by enteric pathogens has commonly been associated with disease outbreaks. Proper management and treatment of pathogen sources are important prerequisites for preventing groundwater contamination. However, non-point sources of pathogen contamination are frequently difficult to identify, and existing approaches for pathogen detection are costly and only provide semi-quantitative information. Microbial indicators that are readily quantified often do not correlate with the presence of pathogens. Pathogens of emerging concern and increasing detections of antibiotic resistance among bacterial pathogens in groundwater are topics of growing concern. Adequate removal of pathogens during soil passage is therefore critical for safe groundwater extraction. Processes that enhance pathogen transport (e.g., high velocity zones and preferential flow) and diminish pathogen removal (e.g., reversible retention and enhanced survival) are of special concern because they increase the risk of groundwater contamination, but are still incompletely understood. Improved theory and modeling tools are needed to analyze experimental data, test hypotheses, understand coupled processes and controlling mechanisms, predict spatial and/or temporal variability in model parameters and uncertainty in pathogen concentrations, assess risk, and develop mitigation and best management approaches to protect groundwater.

  11. Groundwater dating for understanding nitrogen in groundwater systems - Time lag, fate, and detailed flow path ways

    Science.gov (United States)

    Morgenstern, Uwe; Hadfield, John; Stenger, Roland

    2014-05-01

    Nitrate contamination of groundwater is a problem world-wide. Nitrate from land use activities can leach out of the root zone of the crop into the deeper part of the unsaturated zone and ultimately contaminate the underlying groundwater resources. Nitrate travels with the groundwater and then discharges into surface water causing eutrophication of surface water bodies. To understand the source, fate, and future nitrogen loads to ground and surface water bodies, detailed knowledge of the groundwater flow dynamics is essential. Groundwater sampled at monitoring wells or discharges may not yet be in equilibrium with current land use intensity due to the time lag between leaching out of the root zone and arrival at the sampling location. Anoxic groundwater zones can act as nitrate sinks through microbial denitrification. However, the effect of denitrification on overall nitrate fluxes depends on the fraction of the groundwater flowing through such zones. We will show results from volcanic aquifers in the central North Island of New Zealand where age tracers clearly indicate that the groundwater discharges into large sensitive lakes like Lake Taupo and Lake Rotorua are not yet fully realising current land use intensity. The majority of the water discharging into these lakes is decades and up to over hundred years old. Therefore, increases in dairy farming over the last decades are not yet reflected in these old water discharges, but over time these increased nitrate inputs will eventually work their way through the large groundwater systems and increasing N loads to the lakes are to be expected. Anoxic zones are present in some of these aquifers, indicating some denitrification potential, however, age tracer results from nested piezo wells show young groundwater in oxic zones indicating active flow in these zones, while anoxic zones tend to have older water indicating poorer hydraulic conductivity in these zones. Consequently, to evaluate the effect of denitrification

  12. Radium isotopes in groundwater around Fuji Volcano, Japan -application for groundwater dating on volcanic area-

    Science.gov (United States)

    Ohta, T.; Mahara, Y.

    2010-12-01

    Young groundwater dating less than 100 years is possible to be obtained from environmental radioactivity with short half life, 3H+3He, 85Kr, or chemical material, CFC-12. The 3H+3He dating method is excellent method to estimate the residence time of shallow groundwater. The one of advantage of the method is small sample volume. The 3He in groundwater is originated by 3 sources, tritiogenic He, mantle He, radiogenic He produced in rock. Especially, as the contribution of the mantle He is greater than the radiogenic and triogenic, when 3H+3He dating apply for groundwater dating on volcanic area, we have to determine ratio of 3 sources. On the other hand, as 85Kr is only originated from atmosphere, it is excellent groundwater dating tracer on volcanic area. However, as 85Kr is ultra low concentration in groundwater, 85Kr is needed to separate from large amount of ground water about 10^5 L. Young groundwater dating by these methods has both advantages and disadvantages, but the disadvantages of the individual methods can be offset by using multiple tracers. Development of a lot of groundwater dating techniques is desired. Therefore, an application of radium isotopes which is simple origin to groundwater dating on volcanic area was tried. Ra-228 and Ra-226 are progenies of Th and U, respectively. The 228Ra/226Ra in ground waters depends on the Th/U in the relevant rocks. As the 228Ra and 226Ra in shallow groundwater on volcanic area are originated from only rock, and the collection of radium isotopes from groundwater is easier than that of 85Kr, implying that it is possible to be good tracer for volcanic area. We aim that groundwater age obtain from 228Ra/226Ra in groundwater and relevant rock on volcanic area. We determined that 228Ra/226Ra observed with river waters and the relevant rocks. The method applied for Kakitagawa around Fuji Volcano, Japan. The relevant rock of Kakitagawa is Mishima lava flow. Our method compared with 3H+3He dating. The residence time of

  13. Isotope hydrology of deep groundwater in Syria: renewable and non-renewable groundwater and paleoclimate impact

    Science.gov (United States)

    Al-Charideh, A.; Kattaa, B.

    2016-02-01

    The Regional Deep Cretaceous Aquifer (RDCA) is the principal groundwater resource in Syria. Isotope and hydrochemical data have been used to evaluate the geographic zones in terms of renewable and non-renewable groundwater and the inter-relation between current and past recharge. The chemical and isotopic character of groundwater together with radiometric 14C data reflect the existence of three different groundwater groups: (1) renewable groundwater, in RDCA outcropping areas, in western Syria along the Coastal and Anti-Lebanon mountains. The mean δ18O value (-7.2 ‰) is similar to modern precipitation with higher 14C values (up to 60-80 pmc), implying younger groundwater (recent recharge); (2) semi-renewable groundwater, which is located in the unconfined section of the RDCA and parallel to the first zone. The mean δ18O value (-7.0 ‰) is also similar to modern precipitation with a 14C range of 15-45 pmc; (3) non-renewable groundwater found in most of the Syrian interior, where the RDCA becomes confined. A considerable depletion in δ18O (-8.0 ‰) relative to the modern rainfall and low values of 14C (<15 pmc) suggest that the large masses of deep groundwater are non-renewable and related to an older recharge period. The wide scatter of all data points around the two meteoric lines in the δ18O-δ2H diagram indicates considerable variation in recharge conditions. There is limited renewable groundwater in the mountain area, and most of the stored deep groundwater in the RDCA is non-renewable, with corrected 14C ages varying between 10 and 35 Kyr BP.

  14. Dissolution of unirradiated UO{sub 2} fuel in synthetic groundwater. Final report (1996-1998)

    Energy Technology Data Exchange (ETDEWEB)

    Ollila, K. [VTT Chemical Technology, Espoo (Finland)

    1999-05-01

    This study was a part of the EU R and D programme 1994-1998: Nuclear Fission Safety, entitled `Source term for performance assessment of spent fuel as a waste form`. The research carried out at VTT Chemical Technology was focused on the effects of granitic groundwater composition and redox conditions on UO{sub 2} solubility and dissolution mechanisms. The synthetic groundwater compositions simulated deep granitic fresh and saline groundwaters, and the effects of the near-field material, bentonite, on very saline groundwater. Additionally, the Spanish granite/bentonite water was used. The redox conditions (Eh), which are obviously the most important factors that influence on UO{sub 2} solubility under the disposal conditions of spent fuel, varied from strongly oxidising (air-saturated), anaerobic (N{sub 2}, O{sub 2} < l ppm) to reducing (N{sub 2}, low Eh). The objective of the air-saturated dissolution experiments was to yield the maximum solution concentrations of U, and information on the formation of secondary phases that control the concentrations, with different groundwater compositions. The static batch solubility experiments of long duration (up to 1-2 years) were performed using unirradiated UO{sub 2} pellets and powder. Under anaerobic and reducing conditions, the solubilities were also approached from oversaturation. The results of the oxic, air-saturated dissolution experiments with UO{sub 2} powder showed that the increase in the salinity (< 1.7 M) had a minor effect on the measured steady-state concentrations of U. The concentrations, (1.2 ...2.5) x 10{sup -5} M, were at the level of the theoretical solubility of schoepite or another uranyl oxide hydrate, e.g. becquerelite (possibly Na-polyuranate). The higher alkalinity of the fresh (Allard) composition increased the aqueous U concentration. Only some kind of oxidised U-phase (U{sub 3}O{sub 8}-UO{sub 3}) was identified with XRD when studying possible secondary phases after the contact time of one year

  15. Air surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Patton, G.W.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the air surveillance and monitoring programs currently in operation at that Hanford Site. Atmospheric releases of pollutants from Hanford to the surrounding region are a potential source of human exposure. For that reason, both radioactive and nonradioactive materials in air are monitored at a number of locations. The influence of Hanford emissions on local radionuclide concentrations was evaluated by comparing concentrations measured at distant locations within the region to concentrations measured at the Site perimeter. This section discusses sample collection, analytical methods, and the results of the Hanford air surveillance program. A complete listing of all analytical results summarized in this section is reported separately by Bisping (1995).

  16. GARGLING WITH KETAMINE ATTENUATES POST-OPERATIVE SORE THROAT

    OpenAIRE

    Tejashwini; Jagadish

    2014-01-01

    : INTRODUCTION: Postoperative Sore Throat (POST) is a common complication that is unresolved in patients undergoing endotracheal intubation, which is the foremost cause of trauma to the air way mucosa. The reported incident of POST varies from 21% to 65%. We compared the effectiveness of ketamine gargle with placebo in preventing POST after endotracheal intubation. METHODS: A prospective randomized controlled single blind study was conducted involving 60 patients of ASA gr...

  17. Megacity pumping and preferential flow threaten groundwater quality

    Science.gov (United States)

    Khan, Mahfuzur R.; Koneshloo, Mohammad; Knappett, Peter S. K.; Ahmed, Kazi M.; Bostick, Benjamin C.; Mailloux, Brian J.; Mozumder, Rajib H.; Zahid, Anwar; Harvey, Charles F.; van Geen, Alexander; Michael, Holly A.

    2016-09-01

    Many of the world's megacities depend on groundwater from geologically complex aquifers that are over-exploited and threatened by contamination. Here, using the example of Dhaka, Bangladesh, we illustrate how interactions between aquifer heterogeneity and groundwater exploitation jeopardize groundwater resources regionally. Groundwater pumping in Dhaka has caused large-scale drawdown that extends into outlying areas where arsenic-contaminated shallow groundwater is pervasive and has potential to migrate downward. We evaluate the vulnerability of deep, low-arsenic groundwater with groundwater models that incorporate geostatistical simulations of aquifer heterogeneity. Simulations show that preferential flow through stratigraphy typical of fluvio-deltaic aquifers could contaminate deep (>150 m) groundwater within a decade, nearly a century faster than predicted through homogeneous models calibrated to the same data. The most critical fast flowpaths cannot be predicted by simplified models or identified by standard measurements. Such complex vulnerability beyond city limits could become a limiting factor for megacity groundwater supplies in aquifers worldwide.

  18. Annual report of groundwater monitoring at Everest, Kansas, in 2010.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M. (Environmental Science Division)

    2011-03-21

    water of the intermittent creek or in tree branch samples collected at 18 locations along the creek banks. The complete results were reported previously (Argonne 2010). This report presents the results of the second annual sampling events, conducted in 2010. Included in the 2010 monitoring were the following: (1) Continued automatic and manual monitoring of groundwater levels. (2) Groundwater sampling on April 8-9, 2010. (3) Surface water sampling on April 8, 2010. (4) Vegetation sampling on July 28, 2010. (5) Indoor air sampling at selected residences on August 11-12, 2010. The activities are described in Section 2, and the results are discussed in Section 3. Conclusions and recommendations are presented in Section 4.

  19. 2-Phase groundwater and soil vapor extraction site test at McClellan AFB

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, C.; Kingsley, G.B.; Lawrence J. [Radian Corp., Sacramento, CA (United States)] [and others

    1995-09-01

    The innovative 2-phase extraction technique is a method recently patented by Xerox Corporation for simultaneously extracting contaminated groundwater and soil vapor from the subsurface. The 2-phase technique is primarily applicable to those sites with semipermeable soils containing volatile organic compound (VOC) contamination in both soils and groundwater. This technique has several distinct advantages over either conventional soil vapor extraction or groundwater extraction, because it can: cut the dollar per-contaminant-pound cleanup costs by an order of magnitude; simplify the extraction and treatment of both contaminated water and vapor; and shorten remediation times. The U.S. EPA and the Air Force elected to conduct an EPA Site test of the 2-phase Extraction technology at McClellan results indicate: The groundwater flow rate is twice that of the pump-and-treat system. The mass of contaminants from a single well removed increased from 130 lbs/year to more than 5,000 lbs/year, over 30 times more than the pump-and treat rate, with potential for even higher removal rates: 5,000 to 8,000 pounds of contaminants per year. Up to 95% of the contamination was extracted in the vapor phase, where it could be treated more easily and efficiently.

  20. Ra-224 and Ra-226: A New Method for Measuring Groundwater Seepage in Lake Michigan

    Science.gov (United States)

    Stevens, K. R.; Buyan, A. C.; Waples, J. T.

    2008-12-01

    Radium isotopes have been used to estimate groundwater discharge (GWD) in coastal marine waters for decades, but this technique has never before been used in the Laurentian Great Lakes. In this study, we used a RAD7 radon-in-air monitor to measure naturally-occurring radium isotopes Ra-224 (half-life= 3.64 d) and Ra-226 (half-life = 1600 a) in groundwater and three shallow water sites along Lake Michigan's Wisconsin coastline. Radium-224 activities in groundwater ranged from 1153 dpm m-3 in a deep aquifer (New Berlin well no.7) to 31 dpm m-3 in a shallow aquifer (Pryor well). Nearshore Lake Michigan measurements of Ra-224 were lowest at Red Arrow Beach (0.2 dpm m-3), higher in the Milwaukee harbor (GLWI slip, 1.1 dpm m-3) and highest at Harrington Beach (4.1 dpm m-3) and correspond well with groundwater seepage estimates made by Cherkauer et al. (1990) using alternate methods (i.e., where higher radium activity is indicative of higher GWD). These Ra-224 measurements are the first ever made in Lake Michigan (and presumably any of the Great Lakes) and we conclude that, by sampling offshore radium activity gradients, this RAD7 technique is a viable method for directly measuring GWD in Lake Michigan and other freshwater systems.

  1. A groundwater quality index map for Namibia

    Science.gov (United States)

    Bergmann, Thomas; Schulz, Oliver; Wanke, Heike; Püttmann, Wilhelm

    2016-04-01

    Groundwater quality and contamination is a huge concern for the population of Namibia, especially for those living in remote areas. There, most farmers use their own wells to supply themselves and their animals with drinking water. In many cases, except for a few studies that were done in some areas, the only groundwater quality measurements that took place were taken at the time the well was drilled. These data were collected and are available through the national GROWAS-Database. Information on measurements determining the amount of contaminants such as fluoride, TDS, other major ions and nitrate for several thousand wells are provided there. The aim of this study was I) to check the database for its reliability by comparing it to results from different studies and statistical analysis, II) to analyze the database on groundwater quality using different methods (statistical-, pattern- and correlation analysis) and III) to embed our own field work that took place within a selected Namibian region into that analysis. In order to get a better understanding of the groundwater problems in different areas of Namibia, a groundwater quality index map based on GROWAS was created using GIS processing techniques. This map uses several indicators for groundwater quality in relation to selected guidelines and combines them into an index, thus enabling the assessment of groundwater quality with regard to more than one pollutant. The goal of the groundwater quality map is to help identify where the overall groundwater quality is problematic and to communicate these problems. Additionally, suggestions for an enhancement of the database and for new field surveys will be given. The field work was focusing on three farms within an area known for its problematic nitrate concentration in groundwater. There, 23 wells were probed. In order to identify the sources of the contamination, isotopic measurements were executed for three of these wells with high nitrate concentrations

  2. Evaluation of groundwater potential using geospatial techniques

    Science.gov (United States)

    Hussein, Abdul-Aziz; Govindu, Vanum; Nigusse, Amare Gebre Medhin

    2017-09-01

    The issue of unsustainable groundwater utilization is becoming increasingly an evident problem and the key concern for many developing countries. One of the problems is the absence of updated spatial information on the quantity and distribution of groundwater resource. Like the other developing countries, groundwater evaluation in Ethiopia has been usually conducted using field survey which is not feasible in terms of time and resource. This study was conducted in Northern Ethiopia, Wollo Zone, in Gerardo River Catchment district to spatially delineate the groundwater potential areas using geospatial and MCDA tools. To do so, eight major biophysical and environmental factors like geomorphology, lithology, slope, rainfall, land use land cover (LULC), soil, lineament density and drainage density were considered. The sources of these data were satellite image, digital elevation model (DEM), existing thematic maps and metrological station data. Landsat image was used in ERDAS Imagine to drive the LULC of the area, while the geomorphology, soil, and lithology of the area were identified and classified through field survey and digitized from existing maps using the ArcGIS software. The slope, lineament and drainage density of the area were derived from DEM using spatial analysis tools. The rainfall surface map was generated using the thissen polygon interpolation. Finally, after all these thematic maps were organized, weighted value determination for each factor and its field value was computed using IDRSI software. At last, all the factors were integrated together and computed the model using the weighted overlay so that potential groundwater areas were mapped. The findings depicted that the most potential groundwater areas are found in the central and eastern parts of the study area, while the northern and western parts of the Gerado River Catchment have poor potential of groundwater availability. This is mainly due to the cumulative effect of steep topographic and

  3. Evaluation of groundwater potential using geospatial techniques

    Science.gov (United States)

    Hussein, Abdul-Aziz; Govindu, Vanum; Nigusse, Amare Gebre Medhin

    2016-06-01

    The issue of unsustainable groundwater utilization is becoming increasingly an evident problem and the key concern for many developing countries. One of the problems is the absence of updated spatial information on the quantity and distribution of groundwater resource. Like the other developing countries, groundwater evaluation in Ethiopia has been usually conducted using field survey which is not feasible in terms of time and resource. This study was conducted in Northern Ethiopia, Wollo Zone, in Gerardo River Catchment district to spatially delineate the groundwater potential areas using geospatial and MCDA tools. To do so, eight major biophysical and environmental factors like geomorphology, lithology, slope, rainfall, land use land cover (LULC), soil, lineament density and drainage density were considered. The sources of these data were satellite image, digital elevation model (DEM), existing thematic maps and metrological station data. Landsat image was used in ERDAS Imagine to drive the LULC of the area, while the geomorphology, soil, and lithology of the area were identified and classified through field survey and digitized from existing maps using the ArcGIS software. The slope, lineament and drainage density of the area were derived from DEM using spatial analysis tools. The rainfall surface map was generated using the thissen polygon interpolation. Finally, after all these thematic maps were organized, weighted value determination for each factor and its field value was computed using IDRSI software. At last, all the factors were integrated together and computed the model using the weighted overlay so that potential groundwater areas were mapped. The findings depicted that the most potential groundwater areas are found in the central and eastern parts of the study area, while the northern and western parts of the Gerado River Catchment have poor potential of groundwater availability. This is mainly due to the cumulative effect of steep topographic and

  4. Influence of groundwater pumping on streamflow restoration following upstream dam removal

    Science.gov (United States)

    Constantz, J.; Essaid, H.

    2007-01-01

    We compared streamflow in basins under the combined impacts of an upland dam and groundwater pumping withdrawals, by examining streamflow in the presence and absence of each impact. As a qualitative analysis, inter-watersbed streamflow comparisons were performed for several rivers flowing into the east side of the Central Valley, CA. Results suggest that, in the absence of upland dams supporting large reservoirs, some reaches of these rivers might develop ephemeral streamflow in late summer. As a quantitative analysis, we conducted a series of streamflow/ groundwater simulations (using MODFLOW-2000 plus the streamflow routing package, SFR1) for a representative hypothetical watershed, with an upland dam and groundwater pumping in the downstream basin, under humid, semi-arid, and and conditions. As a result of including the impact of groundwater pumping, post-dam removal simulated streamflow was significantly less than natural streamflow. The model predicts extensive ephemeral conditions in the basin during September for both the arid and semi-arid cases. The model predicts continued perennial conditions in the humid case, but spatially weighted, average streamflow of only 71% of natural September streamflow, as a result of continued pumping after dam removal.

  5. RIPGIS-NET: a GIS tool for riparian groundwater evapotranspiration in MODFLOW.

    Science.gov (United States)

    Ajami, Hoori; Maddock, Thomas; Meixner, Thomas; Hogan, James F; Guertin, D Phillip

    2012-01-01

    RIPGIS-NET, an Environmental System Research Institute (ESRI's) ArcGIS 9.2/9.3 custom application, was developed to derive parameters and visualize results of spatially explicit riparian groundwater evapotranspiration (ETg), evapotranspiration from saturated zone, in groundwater flow models for ecohydrology, riparian ecosystem management, and stream restoration. Specifically RIPGIS-NET works with riparian evapotranspiration (RIP-ET), a modeling package that works with the MODFLOW groundwater flow model. RIP-ET improves ETg simulations by using a set of eco-physiologically based ETg curves for plant functional subgroups (PFSGs), and separates ground evaporation and plant transpiration processes from the water table. The RIPGIS-NET program was developed in Visual Basic 2005, .NET framework 2.0, and runs in ArcMap 9.2 and 9.3 applications. RIPGIS-NET, a pre- and post-processor for RIP-ET, incorporates spatial variability of riparian vegetation and land surface elevation into ETg estimation in MODFLOW groundwater models. RIPGIS-NET derives RIP-ET input parameters including PFSG evapotranspiration curve parameters, fractional coverage areas of each PFSG in a MODFLOW cell, and average surface elevation per riparian vegetation polygon using a digital elevation model. RIPGIS-NET also provides visualization tools for modelers to create head maps, depth to water table (DTWT) maps, and plot DTWT for a PFSG in a polygon in the Geographic Information System based on MODFLOW simulation results. © 2011, The Author(s). Ground Water © 2011, National Ground Water Association.

  6. Rare earth element geochemistry of groundwater from a deep seated sandstone aquifer, northern Anhui province, China

    Institute of Scientific and Technical Information of China (English)

    Gui Herong; Sun Linhua; Chen Luwang; Chen Song

    2011-01-01

    Deep coal mines in northern Anhui province,China,provide opportunities for tracing the distribution and fractionation of rare earth elements (REEs) in deep seated environments.Major ions,as well as REE concentrations were measured in groundwater from a sandstone aquifer located between -400 and -280 m.Our results indicate that this groundwater consists of Cl·HCO3-Na or Cl·CO3-Na water types with warm temperature (30.1-31.4℃),circumneutral pH (7.27-8.61) and high levels of total dissolved solids (TDS- 1306-2165 mg/L).Concentrations of REEs in groundwater are high as expressed by their Nd concentrations (0.0086-0.018 μg/L).Except for weak heavy REEs (HREE) enrichment relative to light REEs (LREE),the similarity of REE distribution patterns between groundwater and aquifer rock indicate that enrichment of REEs is considered to be controlled by aquifer rock,as well as by their minerals,whereas the fractionation of REEs is controlled by HREE enriched minerals and,to a lesser extent,by inorganic REE complexes.Ce anomalies normalized to Post Archean Average Shale (PAAS) and aquifer rock are weak,which probably reflect the contribution of reduced conditions in combination with pH,rather than a signature of aquifer rock.

  7. Comparison of deterministic and stochastic methods to predict spatial variation of groundwater depth

    Science.gov (United States)

    Adhikary, Partha Pratim; Dash, Ch. Jyotiprava

    2014-11-01

    Accurate and reliable interpolation of groundwater depth over a region is a pre-requisite for efficient planning and management of water resources. The performance of two deterministic, such as inverse distance weighting (IDW) and radial basis function (RBF) and two stochastic, i.e., ordinary kriging (OK) and universal kriging (UK) interpolation methods was compared to predict spatio-temporal variation of groundwater depth. Pre- and post-monsoon groundwater level data for the year 2006 from 110 different locations over Delhi were used. Analyses revealed that OK and UK methods outperformed the IDW method, and UK performed better than OK. RBF also performed better than IDW and OK. IDW and RBF methods slightly underestimated and both the kriging methods slightly overestimated the prediction of water table depth. OK, RBF and UK yielded 27.52, 27.66 and 51.11 % lower RMSE, 27.49, 35.34 and 51.28 % lower MRE, and 14.21, 16.12 and 21.36 % higher R 2 over IDW. The isodepth-area curves indicated the possibility of exploitation of groundwater up to a depth of 20 m.

  8. An innovative artificial recharge system to enhance groundwater storage in basaltic terrain: example from Maharashtra, India

    Science.gov (United States)

    Bhusari, Vijay; Katpatal, Y. B.; Kundal, Pradeep

    2016-08-01

    The management of groundwater poses challenges in basaltic terrain as its availability is not uniform due to the absence of primary porosity. Indiscriminate excessive withdrawal from shallow as well as deep aquifers for meeting increased demand can be higher than natural recharge, causing imbalance in demand and supply and leading to a scarcity condition. An innovative artificial recharge system has been conceived and implemented to augment the groundwater sources at the villages of Saoli and Sastabad in Wardha district of Maharashtra, India. The scheme involves resectioning of a stream bed to achieve a reverse gradient, building a subsurface dam to arrest subsurface flow, and installation of recharge shafts to recharge the deeper aquifers. The paper focuses on analysis of hydrogeological parameters like porosity, specific yield and transmissivity, and on temporal groundwater status. Results indicate that after the construction of the artificial recharge system, a rise of 0.8-2.8 m was recorded in the pre- and post-monsoon groundwater levels in 12 dug wells in the study area; an increase in the yield was also noticed which solved the drinking water and irrigation problems. Spatial analysis was performed using a geographic information system to demarcate the area of influence of the recharge system due to increase in yields of the wells. The study demonstrates efficacy, technical viability and applicability of an innovative artificial recharge system constructed in an area of basaltic terrain prone to water scarcity.

  9. Can we monitor groundwater head variation from space? Coupling ERS spaceborne microwave observations to groundwater dynamics

    NARCIS (Netherlands)

    Sutanudjaja, E. H.; de Jong, S. M.; van Geer, F. C.; Bierkens, M. F. P.

    2012-01-01

    The objective of this study is to investigate whether the time series of a remote sensing based soil moisture product, referred as the European Remote Sensing Soil Water Index (ERS SWI), correlates to in-situ observations of groundwater heads; and can thus be used for groundwater head prediction. As

  10. Reliability of travel times to groundwater abstraction wells: Application of the Netherlands Groundwater Model - LGM

    NARCIS (Netherlands)

    Kovar K; Leijnse A; Uffink G; Pastoors MJH; Mulschlegel JHC; Zaadnoordijk WJ; LDL; IMD; TNO/NITG; Haskoning

    2005-01-01

    A modelling approach was developed, incorporated in the finite-element method based program LGMLUC, making it possible to determine the reliability of travel times of groundwater flowing to groundwater abstraction sites. The reliability is seen here as a band (zone) around the expected travel-time i

  11. Iowa ground-water quality

    Science.gov (United States)

    Buchmiller, R.C.; Squillace, P.J.; Drustrup, R.D.

    1987-01-01

    The population served by ground-water supplies in Iowa (fig. L4) is estimated to be about 2,392,000, or 82 percent of the total population (U.S. Geological Survey, 1985, p. 211). The population of Iowa is distributed fairly uniformly throughout the State (fig. IB), with 59 percent residing in rural areas or towns of less than 10,000 (U.S. Bureau of the Census, 1982). Surficial aquifers, the Jordan aquifer, and aquifers that form the uppermost bedrock aquifer in a particular area are most commonly used for drinking-water supplies and usually provide ample amounts of good quality water. However, naturally occurring properties or substances such as hardness, dissolved solids, and radioactivity limit the use of water for drinking purposes in some areas of each of the five principal aquifers (fig. 2/4). Median concentrations of nitrate in all aquifers and radium-226 in all aquifers except the Jordan are within the primary drinking-water standards established by the U.S. Environmental Protection Agency (1986a). Median concentrations for dissolved solids in the surficial, Dakota, and Jordan aquifers exceed secondary drinking-water standards established by the U.S. Environmental Protection Agency (1986b).

  12. Groundwater availability of the Mississippi embayment

    Science.gov (United States)

    Clark, Brian R.; Hart, Rheannon M.; Gurdak, Jason J.

    2011-01-01

    Groundwater is an important resource for agricultural and municipal uses in the Mississippi embayment. Arkansas ranks first in the Nation for rice and third for cotton production, with both crops dependent on groundwater as a major source of irrigation requirements. Multiple municipalities rely on the groundwater resources to provide water for industrial and public use, which includes the city of Memphis, Tennessee. The demand for the groundwater resource has resulted in groundwater availability issues in the Mississippi embayment including: (1) declining groundwater levels of 50 feet or more in the Mississippi River Valley alluvial aquifer in parts of eastern Arkansas from agricultural pumping, (2) declining groundwater levels of over 360 feet over the last 90 years in the confined middle Claiborne aquifer in southern Arkansas and northern Louisiana from municipal pumping, and (3) litigation between the State of Mississippi and a Memphis water utility over water rights in the middle Claiborne aquifer. To provide information to stakeholders addressing the groundwater-availability issues, the U.S. Geological Survey Groundwater Resources Program supported a detailed assessment of groundwater availability through the Mississippi Embayment Regional Aquifer Study (MERAS). This assessment included (1) an evaluation of how these resources have changed over time through the use of groundwater budgets, (2) development of a numerical modeling tool to assess system responses to stresses from future human uses and climate trends, and (3) application of statistical tools to evaluate the importance of individual observations within a groundwater-monitoring network. An estimated 12 million acre-feet per year (11 billion gallons per day) of groundwater was pumped in 2005 from aquifers in the Mississippi embayment. Irrigation constitutes the largest groundwater use, accounting for approximately 10 million acre-feet per year (9 billion gallons per day) in 2000 from the Mississippi

  13. Vulnerability assessment of groundwater-dependent ecosystems based on integrated groundwater flow modell construction

    Science.gov (United States)

    Tóth, Ádám; Simon, Szilvia; Galsa, Attila; Havril, Timea; Monteiro Santos, Fernando A.; Müller, Imre; Mádl-Szőnyi, Judit

    2017-04-01

    Groundwater-dependent ecosystems (GDEs) are highly influenced by the amount of groundwater, seasonal variation of precipitation and consequent water table fluctuation and also the anthropogenic activities. They can be regarded as natural surface manifestations of the flowing groundwater. The preservation of environment and biodiversity of these GDEs is an important issue worldwide, however, the water management policy and action plan could not be constructed in absense of proper hydrogeological knowledge. The concept of gravity-driven regional groundwater flow could aid the understanding of flow pattern and interpretation of environmental processes and conditions. Unless the required well data are available, the geological-hydrogeological numerical model of the study area cannot be constructed based only on borehole information. In this case, spatially continuous geophysical data can support groundwater flow model building: systematically combined geophysical methods can provide model input. Integration of lithostratigraphic, electrostratigraphic and hydrostratigraphic information could aid groundwater flow model construction: hydrostratigraphic units and their hydraulic behaviour, boundaries and geometry can be obtained. Groundwater-related natural manifestations, such as GDEs, can be explained with the help of the revealed flow pattern and field mapping of features. Integrated groundwater flow model construction for assessing the vulnerability of GDEs was presented via the case study of the geologically complex area of Tihany Peninsula, Hungary, with the aims of understanding the background and occurrence of groundwater-related environmental phenomena, surface water-groundwater interaction, and revealing the potential effect of anthropogenic activity and climate change. In spite of its important and protected status, fluid flow model of the area, which could support water management and natural protection policy, had not been constructed previously. The 3D

  14. Estimating Groundwater Quality Changes Using Remotely Sensed Groundwater Storage and Multivariate Regression

    Science.gov (United States)

    Gibbons, A.; Thomas, B. F.; Famiglietti, J. S.

    2014-12-01

    Global groundwater dependence is likely to increase with continued population growth and climate-driven freshwater redistribution. Recent groundwater quantity studies have estimated large-scale aquifer depletion rates using monthly water storage variations from NASA's Gravity Recovery and Climate Experiment (GRACE) mission. These innovative approaches currently fail to evaluate groundwater quality, integral to assess the availability of potable groundwater resources. We present multivariate relationships to predict total dissolved solid (TDS) concentrations as a function of GRACE-derived variations in water table depth, dominant land use, and other physical parameters in two important aquifer systems in the United States: the High Plains aquifer and the Central Valley aquifer. Model evaluations were performed using goodness of fit procedures and cross validation to identify general model forms. Results of this work demonstrate the potential to characterize global groundwater potability using remote sensing.

  15. Groundwater management based on monitoring of land subsidence and groundwater levels in the Kanto Groundwater Basin, Central Japan

    Science.gov (United States)

    Furuno, K.; Kagawa, A.; Kazaoka, O.; Kusuda, T.; Nirei, H.

    2015-11-01

    Over 40 million people live on and exploit the groundwater resources of the Kanto Plain. The Plain encompasses metropolitan Tokyo and much of Chiba Prefecture. Useable groundwater extends to the base of the Kanto Plain, some 2500 to 3000 m below sea level. Much of the Kanto Plain surface is at sea level. By the early 1970s, with increasing urbanization and industrial expansion, local overdraft of groundwater resources caused major ground subsidence and damage to commercial and residential structures as well as to local and regional infrastructure. Parts of the lowlands around Tokyo subsided to 4.0 m below sea level; particularly affected were the suburbs of Funabashi and Gyotoku in western Chiba. In the southern Kanto Plain, regulations, mainly by local government and later by regional agencies, led to installation of about 500 monitoring wells and almost 5000 bench marks by the 1990's. Many of them are still working with new monitoring system. Long-term monitoring is important. The monitoring systems are costly, but the resulting data provide continuous measurement of the "health" of the Kanto Groundwater Basin, and thus permit sustainable use of the groundwater resource.

  16. Impacts of Groundwater Pumping on Regional and Global Water Resources

    Science.gov (United States)

    Wada, Yoshihide

    2016-01-01

    Except frozen water in ice and glaciers (68%), groundwater is the world's largest distributed store of freshwater (30%), and has strategic importance to global food and water security. In this chapter, the most recent advances assessing human impact on regional and global groundwater resources are reviewed. This chapter critically evaluates the recently advanced modeling approaches quantifying the effect of groundwater pumping in regional and global groundwater resources and the evidence of feedback to the Earth system including sea-level rise associated with groundwater use. At last, critical challenges and opportunities are identified in the use of groundwater to adapt to growing food demand and uncertain climate.

  17. Groundwater Systems and Resources in the Ordos Basin, China

    Institute of Scientific and Technical Information of China (English)

    HOU Guangcai; LIANG Yongping; SU Xiaosi; ZHAO Zhenghong; TAO Zhengping; YIN Lihe; YANG Yuncheng; WANG Xiaoyong

    2008-01-01

    The Ordos Basin is.a large-scalesedimentary basin in northwestern China. The hydrostratigraphic units from bottom to top are pre-Cambrian metamorphic rocks, Lower Paleozoic carbonate rocks, Upper Paleozoic to Mesozoic clastic rocks and Cenozoic deposits. The total thickness is up to 6000 m. Three groundwater systems are present in the Ordos Basin, based on the geological settings, I.e. The karst groundwater system, the Cretaceous dastic groundwater system and the Quaternary groundwater system. This paper describes systematically the groundwater flow patterns of each system and overall assessment of groundwater resources.

  18. Groundwater Level Status Report for 2005 Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    S.P. Allen; R.J. Koch

    2006-05-15

    The status of groundwater level monitoring at Los Alamos National Laboratory (LANL) in 2005 is provided in this report. The Groundwater Level Monitoring Project was instituted in 2005 to provide a framework for the collection and processing of quality controlled groundwater level data. This report summarizes groundwater level data for 137 monitoring wells, including 41 regional aquifer wells, 22 intermediate wells, and 74 alluvial wells. Pressure transducers were installed in 118 monitoring wells for continuous monitoring of groundwater levels. Time-series hydrographs of groundwater level data are presented along with pertinent construction and location information for each well.

  19. Windows of Opportunity for Groundwater Management

    Science.gov (United States)

    Foster, T.; Brozovic, N.; Butler, A. P.

    2015-12-01

    To date, there has been little attention focused on how the value and effectiveness of groundwater management is influenced by the timing of regulatory intervention relative to aquifer depletion. To address this question, we develop an integrated framework that couples an agro-economic model of farmers' field-level irrigation decision-making with a model of a groundwater abstraction borehole. Unlike existing models that only consider the impact of aquifer depletion on groundwater extraction costs, our model also captures the dynamic changes in well productivity and how these in turn affect crop yields and farmer incomes. We use our model to analyze how the value of imposing groundwater quotas is affected by the prior level of depletion before regulations are introduced. Our results demonstrate that there is a range of aquifer conditions within which regulating groundwater use will deliver long-term economic benefits for farmers. In this range, restricting abstraction rates slows the rate of change in well yields and, as a result, increases agricultural production over the simulated planning horizon. Contrastingly, when current saturated thickness is outside this range, regulating groundwater use will provide negligible social benefits and will impose large negative impacts on farm-level profits. We suggest that there are 'windows of opportunity' for managing aquifer depletion that are a function of local hydrology as well as economic characteristics. Regulation that is too early will harm the rural economy needlessly, while regulation that is too late will be unable to prevent aquifer exhaustion. The insights from our model can be a valuable tool to help inform policy decisions about when, and at what level, regulations should be implemented in order to maximize the benefits obtained from limited groundwater resources.

  20. Groundwater conditions in Utah, spring of 2012

    Science.gov (United States)

    Burden, Carole B.; Allen, David V.; Holt, Christopher M.; Fisher, Martel J.; Downhour, Paul; Smith, Lincoln; Eacret, Robert J.; Gibson, Travis L.; Slaugh, Bradley A.; Whittier, Nickolas R.; Howells, James H.; Christiansen, Howard K.

    2012-01-01

    This is the forty-ninth in a series of annual reports that describe groundwater conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing groundwater conditions. This report, like the others in the series, contains information on well construction, groundwater withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of groundwater. Supplementary data are included in reports of this series only for those years or areas that are important to a discussion of changing groundwater conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of groundwater development in the State for calendar year 2011. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is also available online at http:// www.waterrights.utah.gov/techinfo/ and http://ut.water.usgs. gov/publications/GW2012.pdf. Groundwater conditions in Utah for calendar year 2010 are reported in Burden and others (2011) and available online at http://ut.water.usgs.gov/ publications/GW2011.pdf.

  1. Groundwater conditions in Utah, spring of 2011

    Science.gov (United States)

    Burden, Carole B.; Allen, David V.; Marston, Thomas M.; Fisher, Martel J.; Balling, Ted J.; Downhour, Paul; Guzman, Manuel; Eacret, Robert J.; Slaugh, Bradley A.; Swenson, Robert L.; Howells, James H.; Christiansen, Howard K.

    2011-01-01

    This is the forty-eighth in a series of annual reports that describe groundwater conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing groundwater conditions. This report, like the others in the series, contains information on well construction, groundwater withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of groundwater. Supplementary data are included in reports of this series only for those years or areas that are important to a discussion of changing groundwater conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of groundwater development in the State for calendar year 2010. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is also available online at http:// www.waterrights.utah.gov/techinfo/ and http://ut.water.usgs. gov/publications/GW2011.pdf. Groundwater conditions in Utah for calendar year 2009 are reported in Burden and others (2010) and available online at http://ut.water.usgs.gov/ publications/GW2010.pdf.

  2. Groundwater conditions in Utah, spring of 2014

    Science.gov (United States)

    Burden, Carole B.; Birken, Adam S.; Gerner, Steven J.; Carricaburu, John P.; Derrick, V. Noah; Downhour, Paul; Smith, Lincoln; Eacret, Robert J.; Gibson, Travis L.; Slaugh, Bradley A.; Whittier, Nickolas R.; Howells, James H.; Christiansen, Howard K.; Fisher, Martel J.

    2014-01-01

    This is the fifty-first in a series of annual reports that describe groundwater conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing groundwater conditions.This report, like the others in the series, contains information on well construction, groundwater withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of groundwater. Supplementary data are included in reports of this series only for those years or areas that are important to a discussion of changing groundwater conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of groundwater development in the State for calendar year 2013. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is also available online at http://www.waterrights.utah.gov/techinfo/ and http://ut.water. usgs.gov/publications/GW2014.pdf. Groundwater conditions in Utah for calendar year 2012 are reported in Burden and others (2013) and are available online at http://ut.water.usgs. gov/publications/GW2013.pdf

  3. Groundwater conditions in Utah, spring of 2010

    Science.gov (United States)

    Burden, Carole B.; Allen, David V.; Cederberg, Jay R.; Fisher, Martel J.; Freeman, Michael L.; Downhour, Paul; Enright, Michael; Eacret, Robert J.; Guzman, Manuel; Slaugh, Bradley A.; Swenson, Robert L.; Howells, James H.; Christiansen, Howard K.

    2010-01-01

    This is the forty-seventh in a series of annual reports that describe groundwater conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing groundwater conditions. This report, like the others in the series, contains information on well construction, groundwater withdrawal from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to wells constructed for new appropriations of groundwater. Supplementary data are included in reports of this series only for those years or areas which are important to a discussion of changing groundwater conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of groundwater development in the State for calendar year 2009. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Resources and Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is also available online at http://www. waterrights.utah.gov/techinfo/ and http://ut.water.usgs.gov/ publications/GW2010.pdf. Groundwater conditions in Utah for calendar year 2008 are reported in Burden and others (2009) and available online at http://ut.water.usgs.gov/publications/ GW2009.pdf.

  4. Groundwater conditions in Utah, spring of 2016

    Science.gov (United States)

    Burden, Carole B.; Birken, Adam S.; Carricaburu, John P.; Jones, Katherine K.; Derrick, V. Noah; Downhour, Paul; Smith, Lincoln; Eacret, Robert J.; Gibson, Travis L.; Slaugh, Bradley A.; Whittier, Nickolas R.; Freel, Andrew D.; Christiansen, Howard K.; Fisher, Martel J.

    2016-01-01

    This is the fifty-third in a series of annual reports that describe groundwater conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing groundwater conditions.This report, like the others in the series, contains information on well construction, groundwater withdrawals from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to new wells constructed for withdrawal of groundwater. Supplementary data are included in reports of this series only for those years or areas that are important to a discussion of changing groundwater conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of groundwater development in the State for calendar year 2015. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is also available online at http://www.waterrights.utah.gov/techinfo/ and http://ut.water.usgs.gov/publications/GW2016.pdf. Groundwater conditions in Utah for calendar year 2014 are reported in Burden and others (2015) and are available online at http://ut.water.usgs.gov/publications/GW2015.pdf

  5. Groundwater conditions in Utah, spring of 2015

    Science.gov (United States)

    Burden, Carole B.; Birken, Adam S.; Carricaburu, John P.; Fisher, Martel J.; Derrick, V. Noah; Downhour, Paul; Smith, Lincoln; Eacret, Robert J.; Gibson, Travis L.; Slaugh, Bradley A.; Whittier, Nickolas R.; Howells, James H.; Christiansen, Howard K.

    2015-01-01

    This is the fifty-second in a series of annual reports that describe groundwater conditions in Utah. Reports in this series, published cooperatively by the U.S. Geological Survey and the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality, provide data to enable interested parties to maintain awareness of changing groundwater conditions.This report, like the others in the series, contains information on well construction, groundwater withdrawals from wells, water-level changes, precipitation, streamflow, and chemical quality of water. Information on well construction included in this report refers only to new wells constructed for withdrawal of groundwater. Supplementary data are included in reports of this series only for those years or areas that are important to a discussion of changing groundwater conditions and for which applicable data are available.This report includes individual discussions of selected significant areas of groundwater development in the State for calendar year 2014. Most of the reported data were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Environmental Quality, Division of Water Quality. This report is also available online at http://www.waterrights.utah.gov/techinfo/ and http://ut.water.usgs.gov/publications/GW2015.pdf. Groundwater conditions in Utah for calendar year 2013 are reported in Burden and others (2014) and are available online at http://ut.water.usgs.gov/publications/GW2014.pdf.

  6. Groundwater recharge from point to catchment scale

    Science.gov (United States)

    Leterme, Bertrand; Di Ciacca, Antoine; Laloy, Eric; Jacques, Diederik

    2016-04-01

    Accurate estimation of groundwater recharge is a challenging task as only a few devices (if any) can measure it directly. In this study, we discuss how groundwater recharge can be calculated at different temporal and spatial scales in the Kleine Nete catchment (Belgium). A small monitoring network is being installed, that is aimed to monitor the changes in dominant processes and to address data availability as one goes from the point to the catchment scale. At the point scale, groundwater recharge is estimated using inversion of soil moisture and/or water potential data and stable isotope concentrations (Koeniger et al. 2015). At the plot scale, it is proposed to monitor the discharge of a small drainage ditch in order to calculate the field groundwater recharge. Electrical conductivity measurements are necessary to separate shallow from deeper groundwater contribution to the ditch discharge (see Di Ciacca et al. poster in session HS8.3.4). At this scale, two or three-dimensional process-based vadose zone models will be used to model subsurface flow. At the catchment scale though, using a mechanistic, process-based model to estimate groundwater recharge is debatable (because of, e.g., the presence of numerous drainage ditches, mixed land use pixels, etc.). We therefore investigate to which extent various types of surrogate models can be used to make the necessary upscaling from the plot scale to the scale of the whole Kleine Nete catchment. Ref. Koeniger P, Gaj M, Beyer M, Himmelsbach T (2015) Review on soil water isotope based groundwater recharge estimations. Hydrological Processes, DOI: 10.1002/hyp.10775

  7. Post-Concussion Syndrome

    Science.gov (United States)

    Post-concussion syndrome Overview By Mayo Clinic Staff Post-concussion syndrome is a complex disorder in which various symptoms — ... sometimes months after the injury that caused the concussion. Concussion is a mild traumatic brain injury that ...

  8. Environmental Aspects of Two Volatile Organic Compound Groundwater Treatment Designs at the Rocky Flats Site - 13135

    Energy Technology Data Exchange (ETDEWEB)

    Michalski, Casey C.; DiSalvo, Rick; Boylan, John [Stoller LMS Team, 11025 Dover Street, Suite 1000, Westminster, CO 80021 (United States)

    2013-07-01

    DOE's Rocky Flats Site in Colorado is a former nuclear weapons production facility that began operations in the early 1950's. Because of releases of hazardous substances to the environment, the federally owned property and adjacent offsite areas were placed on the CERCLA National Priorities List in 1989. The final remedy was selected in 2006. Engineered components of the remedy include four groundwater treatment systems that were installed before closure as CERCLA-accelerated actions. Two of the systems, the Mound Site Plume Treatment System and the East Trenches Plume Treatment System, remove low levels of volatile organic compounds using zero-valent iron media, thereby reducing the loading of volatile organic compounds in surface water resulting from the groundwater pathway. However, the zero-valent iron treatment does not reliably reduce all volatile organic compounds to consistently meet water quality goals. While adding additional zero-valent iron media capacity could improve volatile organic compound removal capability, installation of a solar powered air-stripper has proven an effective treatment optimization in further reducing volatile organic compound concentrations. A comparison of the air stripper to the alternative of adding additional zero-valent iron capacity to improve Mound Site Plume Treatment System and East Trenches Plume Treatment System treatment based on several key sustainable remediation aspects indicates the air stripper is also more 'environmentally friendly'. These key aspects include air pollutant emissions, water quality, waste management, transportation, and costs. (authors)

  9. Impact of artificial recharge on dissolved noble gases in groundwater in California.

    Science.gov (United States)

    Cey, Bradley D; Hudson, G Bryant; Moran, Jean E; Scanlon, Bridget