WorldWideScience

Sample records for surfactant-enhanced aquifer remediation

  1. Surfactant-Enhanced Aquifer Remediation (SEAR) Implementation Manual

    Science.gov (United States)

    2003-04-01

    contaminants (e.g., creosote ) when temperature augmentation for viscosity reduction is not otherwise feasible. The surfactant flooding wellfield will...Section 4.3) to terminate continued hydraulic control measures, for remediation by chemical oxidation, vacuum-enhanced pumping, enhanced bioremediation

  2. Surfactant-enhanced remediation of a trichloroethene-contaminated aquifer. 1. Transport of triton X-100

    Science.gov (United States)

    Smith, J.A.; Sahoo, D.; Mclellan, H.M.; Imbrigiotta, T.E.

    1997-01-01

    Transport of a nonionic surfactant (Triton X-100) at aqueous concentrations less than 400 mg/L through a trichloroethene-contaminated sand-and-gravel aquifer at Picatinny Arsenal, NJ, has been studied through a series of laboratory and field experiments. In the laboratory, batch and column experiments were conducted to quantify the rate and amount of Triton X-100 sorption to the aquifer sediments. In the field, a 400 mg/L aqueous Triton X-100 solution was injected into the aquifer at a rate of 26.5 L/min for a 35-d period. The transport of Triton X-100 was monitored by sampling and analysis of groundwater at six locations surrounding the injection well. Equilibrium batch sorption experiments showed that Triton X-100 sorbs strongly and nonlinearly to the field soil with the sharpest inflection point of the isotherm occurring at an equilibrium aqueous Triton X-100 concentration close to critical micelle concentration. Batch, soil column, and field experimental data were analyzed with zero-, one-, and two- dimensional (respectively) transient solute transport models with either equilibrium or rate-limited sorption. These analyses reveal that Triton X- 100 sorption to the aquifer solids is slow relative to advective and dispersive transport and that an equilibrium sorption model cannot simulate accurately the observed soil column and field data. Comparison of kinetic sorption parameters from batch, column, and field transport data indicate that both physical heterogeneities and Triton X-100 mass transfer between water and soil contribute to the kinetic transport effects.Transport of a nonionic surfactant (Triton X-100) at aqueous concentrations less than 400 mg/L through a trichloroethene-contaminated sand-and-gravel aquifer was studied. Equilibrium batch sorption experiments showed that Triton X-100 sorbs strongly and nonlinearly to the field soil with the sharpest inflection point of the isotherm occurring at an equilibrium aqueous Triton X-100 concentration close to

  3. Surfactant-enhanced remediation of a trichloroethene-contaminated aquifer. 2. Transport of TCE

    Science.gov (United States)

    Sahoo, D.; Smith, J.A.; Imbrigiotta, T.E.; Mclellan, H.M.

    1998-01-01

    Field studies were conducted under an induced gradient in a trichloroethene (TCE)-contaminated aquifer at Picatinny Arsenal, NJ, to study (a) the rate-limited desorption of TCE from aquifer sediments to water and (b) the effect of a surfactant (Triton X-100) on the desorption and transport of TCE. Clean water was injected into the contaminated aquifer for 206 day. Triton X-100 was added for a 36-day period (days 36-71 from the start of clean water injection). The effect of Triton X-100 on the desorption and transport of TCE in the field was examined by observing the concentrations of these two solutes in four monitoring wells 3-9 m from the injection wells. These data show a small but discernible increase in the TCE concentration in two of the wells corresponding approximately to the time when surfactant reaches the wells; in the other two monitoring wells, the increase in TCE concentration is negligible. A solute transport model that assumes local sorption equilibrium and used a laboratory-derived distribution coefficient could not adequately describe TCE desorption and transport observed in the aquifer. Two model formulations that accounted for rate-limited sorption - two-site and multisite models - fit the data well. TCE concentrations after surfactant injection were underpredicted by the models unless mass transfer rate was increased to account for the effect of surfactant on the rate of TCE desorption. The concentration data from the two wells and the model analysis suggest that the rate of TCE desorption is increased (by approximately 30%) as a result of Triton X-100 injection.Field studies were conducted under an induced gradient in a trichloroethene (TCE)-contaminated aquifer at Picatinny Arsenal, NJ, to study (a) the rate-limited desorption of TCE from aquifer sediments to water and (b) the effect of a surfactant (Triton X-100) on the desorption and transport of TCE. Clean water was injected into the contaminated aquifer for 206 day. Triton X-100 was added

  4. Effects of permeability heterogeneity on the performance of surfactant-enhanced remediation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K.S. [Kyonggi Univ., Seoul (Korea, Republic of)

    2010-07-01

    The subsurface contamination by nonaqueous phase liquids (NAPLs) is a complicated process and difficult to treat because these organic contaminants tend to adsorb onto the soil matrix. They have low water solubility and a limited rate of mass transfer for biodegradation. NAPLs may leach from the soil for a longer period of time and may eventually become a long-term continuous contamination source of the soil and groundwater. One method to enhance pump-and-treat aquifer remediation performance involves surfactant-enhanced aquifer remediation (SEAR). Because their success depends on the delivery of injected chemical and water into the subsurface to contact the organic liquids, geologic heterogeneities are likely the main factors which reduce the effectiveness of SEAR processes. This paper presented a study that involved numerical simulations to assess the effect of spatial variability of aquifer permeability on NAPL recovery and injection pressure as well as spatial and temporal distributions of NAPLs during the remediation process. The paper outlined the mathematical backgrounds, numerical model, and results and discussion. It was concluded the effectiveness of SEAR is sensitive to injection time due to dispersion of surfactant slug with the presence of a higher degree of heterogeneity. 6 refs., 3 figs.

  5. Geotechnical behaviour of low-permeability soils in surfactant-enhanced electrokinetic remediation.

    Science.gov (United States)

    López-Vizcaíno, Rubén; Navarro, Vicente; Alonso, Juan; Yustres, Ángel; Cañizares, Pablo; Rodrigo, Manuel A; Sáez, Cristina

    2016-01-01

    Electrokinetic processes provide the basis of a range of very interesting techniques for the remediation of polluted soils. These techniques consist of the application of a current field in the soil that develops different transport mechanisms capable of mobilizing several types of pollutants. However, the use of these techniques could generate nondesirable effects related to the geomechanical behavior of the soil, reducing the effectiveness of the processes. In the case of the remediation of polluted soils with plasticity index higher than 35, an excessive shrinkage can be observed in remediation test. For this reason, the continued evaporation that takes place in the sample top can lead to the development of cracks, distorting the electrokinetic transport regime, and consequently, the development of the operation. On the other hand, when analyzing silty soils, in the surroundings of injection surfactant wells, high seepages can be generated that give rise to the development of piping processes. In this article methods are described to allow a reduction, or to even eliminate, both problems.

  6. Drivers and applications of integrated clean-up technologies for surfactant-enhanced remediation of environments contaminated with polycyclic aromatic hydrocarbons (PAHs).

    Science.gov (United States)

    Liang, Xujun; Guo, Chuling; Liao, Changjun; Liu, Shasha; Wick, Lukas Y; Peng, Dan; Yi, Xiaoyun; Lu, Guining; Yin, Hua; Lin, Zhang; Dang, Zhi

    2017-06-01

    Surfactant-enhanced remediation (SER) is considered as a promising and efficient remediation approach. This review summarizes and discusses main drivers on the application of SER in removing polycyclic aromatic hydrocarbons (PAHs) from contaminated soil and water. The effect of PAH-PAH interactions on SER efficiency is, for the first time, illustrated in an SER review. Interactions between mixed PAHs could enhance, decrease, or have no impact on surfactants' solubilization power towards PAHs, thus affecting the optimal usage of surfactants for SER. Although SER can transfer PAHs from soil/non-aqueous phase liquids to the aqueous phase, the harmful impact of PAHs still exists. To decrease the level of PAHs in SER solutions, a series of SER-based integrated cleanup technologies have been developed including surfactant-enhanced bioremediation (SEBR), surfactant-enhanced phytoremediation (SEPR) and SER-advanced oxidation processes (SER-AOPs). In this review, the general considerations and corresponding applications of the integrated cleanup technologies are summarized and discussed. Compared with SER-AOPs, SEBR and SEPR need less operation cost, yet require more treatment time. To successfully achieve the field application of surfactant-based technologies, massive production of the cost-effective green surfactants (i.e. biosurfactants) and comprehensive evaluation of the drivers and the global cost of SER-based cleanup technologies need to be performed in the future. Copyright © 2017. Published by Elsevier Ltd.

  7. Groundwater Remediation in a Floodplain Aquifer at Shiprock, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Dave [Navarro Research and Engineering; Miller, David [Navarro Research and Engineering; Kautsky, Mark [U. S. Department of Energy, Office of Legacy Management; Dander, David [Navarro Research and Engineering; Nofchissey, Joni [Navajo Nation Division of Natural Resources

    2016-03-06

    A uranium- and vanadium-ore-processing mill operated from 1954 to 1968 within the Navajo Nation near Shiprock, New Mexico. By September 1986, all tailings and structures on the former mill property were encapsulated in a disposal cell built on top of two existing tailings piles on the Shiprock site (the site) [1]. Local groundwater was contaminated by multiple inorganic constituents as a result of the milling operations. The U.S. Department of Energy (DOE) took over management of the site in 1978 as part of the Uranium Mill Tailings Remedial Action (UMTRA) Project. The DOE Office of Legacy Management currently manages ongoing activities at the former mill facility, including groundwater remediation. Remediation activities are designed primarily to reduce the concentrations and total plume mass of the mill-related contaminants sulfate, uranium, and nitrate. In addition to contaminating groundwater in alluvial and bedrock sediments directly below the mill site, ore processing led to contamination of a nearby floodplain bordering the San Juan River. Groundwater in a shallow alluvial aquifer beneath the floodplain is strongly influenced by the morphology of the river channel as well as changing flows in the river, which provides drainage for regional runoff from the San Juan Mountains of Colorado. As part of a recent study of the floodplain hydrology, a revised conceptual model was developed for the alluvial aquifer along with an updated status of contaminant plumes that have been impacted by more than 10 years of groundwater pumping for site remediation purposes. Several findings from the recent study will be discussed here.

  8. A comparative research of different ensemble surrogate models based on set pair analysis for the DNAPL-contaminated aquifer remediation strategy optimization

    Science.gov (United States)

    Hou, Zeyu; Lu, Wenxi; Xue, Haibo; Lin, Jin

    2017-08-01

    Surrogate-based simulation-optimization technique is an effective approach for optimizing the surfactant enhanced aquifer remediation (SEAR) strategy for clearing DNAPLs. The performance of the surrogate model, which is used to replace the simulation model for the aim of reducing computation burden, is the key of corresponding researches. However, previous researches are generally based on a stand-alone surrogate model, and rarely make efforts to improve the approximation accuracy of the surrogate model to the simulation model sufficiently by combining various methods. In this regard, we present set pair analysis (SPA) as a new method to build ensemble surrogate (ES) model, and conducted a comparative research to select a better ES modeling pattern for the SEAR strategy optimization problems. Surrogate models were developed using radial basis function artificial neural network (RBFANN), support vector regression (SVR), and Kriging. One ES model is assembling RBFANN model, SVR model, and Kriging model using set pair weights according their performance, and the other is assembling several Kriging (the best surrogate modeling method of three) models built with different training sample datasets. Finally, an optimization model, in which the ES model was embedded, was established to obtain the optimal remediation strategy. The results showed the residuals of the outputs between the best ES model and simulation model for 100 testing samples were lower than 1.5%. Using an ES model instead of the simulation model was critical for considerably reducing the computation time of simulation-optimization process and maintaining high computation accuracy simultaneously.

  9. Surfactant enhanced non-classical extraction

    International Nuclear Information System (INIS)

    Szymanowski, J.

    1999-01-01

    Surfactant enhanced non-classical extractions are presented and discussed. They include micellar enhanced ultrafiltration and cloud point extraction. The ideas of the processes are given and the main features are presented. They are compared to the classical solvent extraction. The fundamental of micellar solutions and their solubilization abilities are also discussed. (author)

  10. Experimental and numerical study for seawater intrusion remediation in heterogeneous coastal aquifer.

    Science.gov (United States)

    Ahmed, Abdelkader T

    2017-08-01

    The contamination of fresh groundwater by saltwater intrusion (SWI) becomes a worldwide alarming problem, which threatens all countries depending on groundwater abstraction from coastal areas. Various control and treatment strategies have been suggested to prevent SWI. The construction of subsurface physical barriers is one of the most practical implementation methods to prevent SWI. In this work, the use of subsurface dam as a remediation and protection tool was investigated in a heterogeneous aquifer via lab scale experiments and numerical simulation. The experiments depended on a novel automated imaged analysis method for SWI measurements. Glass beads of different grain sizes were used in sandbox experiments. The simulation works adopted the SEAWAT code for validation of the experimental results and making numerical sensitivity analyses for affecting parameters. Results proved the significant impact of using sub water dams with heterogonous aquifers. The remediation impacts of the dam was captured clearly in preventing and backwashing of the existed SWI. The results revealed also that the heterogeneous aquifers with high permeability in the bottom boundary behave closer to the homogenous aquifers in SWI than those having low hydraulic conductivity in the bottom. Sensitivity analyses results showed that the closer dam to seawater boundary led to the quicker and more effective backwashing process. Results exhibited also that the dam height with 50% of the aquifer dam has the ability to hold the seawater so long as the hydraulic gradient is high and dams with 67% of aquifer height prevent the saltwater intrusion completely. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Advances in hydrocarbons spill remediation in Barreal-Belen: proposed measures for the protection of aquifers

    International Nuclear Information System (INIS)

    Vargas Fallas, Luis Carlos

    2011-01-01

    The advances accomplished with regard to hydrocarbons spill remediation, through 2009 are shown and the costs made in the process are listed. In the Central Valley have been located about 160 gas stations on major aquifers at risk of contamination, in light of the case of hydrocarbons spill happened in Barreal-Belen in 2004, discovered by chance during the inspection to a nearby well. The study instruments of the vulnerability to contamination of aquifers are analyzed. A proposal of measures is presented, which should be taken to ensure control over the risk of further spillage and for proper management of waters. (author) [es

  12. Aquifer characterization and groundwater modeling in support of remedial actions at the Weldon Spring Site

    International Nuclear Information System (INIS)

    Durham, L.A.; Carman, J.D.

    1993-01-01

    Aquifer characterization studies were performed to develop a hydrogeologic understanding of an unconfined shallow aquifer at the Weldon Spring site west of St. Louis, Missouri. The 88-ha site became contaminated because of uranium and thorium processing and disposal activities that took place from the 1940s through the 1960s. Slug and pumping tests provided valuable information on the lateral distribution of hydraulic conductivities, and packer tests and lithologic information were used to determine zones of contrasting hydrologic properties within the aquifer. A three-dimensional, finite- element groundwater flow model was developed and used to simulate the shallow groundwater flow system at the site. The results of this study show that groundwater flow through the system is predominantly controlled by a zone of fracturing and weathering in the upper portion of the limestone aquifer. The groundwater flow model, developed and calibrated from field investigations, improved the understanding of the hydrogeology and supported decisions regarding remedial actions at the site. The results of this study illustrate the value, in support of remedial actions, of combining field investigations with numerical modeling to develop an improved understanding of the hydrogeology at the site

  13. Lab-scale investigation on remediation of diesel-contaminated aquifer using microwave energy.

    Science.gov (United States)

    Falciglia, Pietro P; Maddalena, Riccardo; Mancuso, Giuseppe; Messina, Valeria; Vagliasindi, Federico G A

    2016-02-01

    Aquifer contamination with diesel fuel is a worldwide environmental problem, and related available remediation technologies may not be adequately efficient, especially for the simultaneous treatment of both solid and water phases. In this paper, a lab-scale 2.45 GHz microwave (MW) treatment of an artificially diesel-contaminated aquifer was applied to investigate the effects of operating power (160, 350 and 500 W) and time on temperature profiles and contaminant removal from both solid and water phases. Results suggest that in diesel-contaminated aquifer MW remediation, power significantly influences the final reachable temperature and, consequently, contaminant removal kinetics. A maximum temperature of about 120 °C was reached at 500 W. Observed temperature values depended on the simultaneous irradiation of both aquifer grains and groundwater. In this case, solid phase heating is limited by the maximum temperature that interstitial water can reach before evaporation. A minimal residual diesel concentration of about 100 mg kg(-1) or 100 mg L(-1) was achieved by applying a power of 500 W for a time of 60 min for the solid or water phase, respectively. Measured residual TPH fractions showed that MW heating resulted in preferential effects of the removal of different TPH molecular weight fractions and that the evaporation-stripping phenomena plays a major role in final contaminant removal processes. The power low kinetic equation shows an excellent fit (r(2) > 0.993) with the solid phase residual concentration observed for all the powers investigated. A maximum diesel removal of 88 or 80% was observed for the MW treatment of the solid or water phase, respectively, highlighting the possibility to successfully and simultaneously remediate both the aquifer phases. Consequently, MW, compared to other biological or chemical-physical treatments, appears to be a better choice for the fast remediation of diesel-contaminated aquifers. Copyright © 2015 Elsevier

  14. Surfactant-enhanced electrokinetic remediation of soil contaminated with hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Yang, J.W.; Park, J.Y.; Lee, H.H.; Cho, H.J. [Dept. of Chemical Engineering, Korea Advanced Inst. of Science and Technology, Taejon (Korea)

    2001-07-01

    Removal of hydrophobic organic contaminants (HOCs) using electrokinetic method was studied in a model system. Kaolinite and phenanthrene were selected as the model clay soil and representative HOC. Three different types of surfactants, APG (alkyl polyglucoside), Brij30 (polyoxyethylene 4 lauryl ether), and SDS (sodium dodecyl sulfate), were used to enhance the solubility of HOCs. Electrokinetic (EK) column experiments were performed using water, surfactant solution, and acetate buffer solution under a constant current condition. Voltage and flow through the soil system were interpreted with time. Electrolyte pH at the anode and cathode compartments was observed for operation time. Removal efficiency of phenanthrene was examined after the end of EK operation during 2, 4, and 6 weeks. (orig.)

  15. Application of Fe-Cu/Biochar System for Chlorobenzene Remediation of Groundwater in Inhomogeneous Aquifers

    Directory of Open Access Journals (Sweden)

    Xu Zhang

    2017-12-01

    Full Text Available Chlorobenzene (CB, as a typical Volatile Organic Contaminants (VOC, is toxic, highly persistent and easily migrates in water, posing a significant risk to human health and subsurface ecosystems. Therefore, exploring effective approaches to remediate groundwater contaminated by CB is essential. As an enhanced micro-electrolysis system for CB-contaminated groundwater remediation, this study attempted to couple the iron-copper bimetal with biochar. Two series of columns using sands with different grain diameters were used, consisting of iron, copper and biochar fillings as the permeable reactive barriers (PRBs, to simulate the remediation of CB-contaminated groundwater in homogeneous and heterogeneous aquifers. Regardless of the presence of homogeneous or heterogeneous porous media, the CB concentrations in the effluent from the PRB columns were significantly lower than the natural sandy columns, suggesting that the iron and copper powders coupled with biochar particles could have a significant removal effect compared to the natural sand porous media in the first columns. CB was transported relatively quickly in the heterogeneous porous media, likely due to the fact that the contaminant residence time is proportional to the infiltration velocities in the different types of porous media. The average effluent CB concentrations from the heterogeneous porous media were lower than those from homogeneous porous media. The heterogeneity retarded the vertical infiltration of CB, leading to its extended lateral distribution. During the treatment process, benzene and phenol were observed as the products of CB degradation. The ultimate CB removal efficiency was 61.4% and 68.1%, demonstrating that the simulated PRB system with the mixture of iron, copper and biochar was effective at removing CB from homogeneous and heterogeneous aquifers.

  16. Numerical modeling of Etla Valley aquifer, Oax., Mexico: Evolution and remediation scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Flores-Marquez, E. L; Martinez-Serrano, R. G; Chavez, R. E; Crusillo, Y [Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Mexico D.F. (Mexico); Jimenez, G [Facultad de Ingenieria, Benemerita Universidad Autonoma de Puebla, Puebla (Mexico); Camops-Enriquez, O [Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Mexico D.F. (Mexico)

    2008-01-15

    Short-term evolution (for 2001, 2005 and 2015) for the shallow aquifer of Etla Valley, Oaxaca, southern Mexico, was simulated based in a 3D hydrological model elaborated from the available geological, geophysical, geochemical, and hydrologic parameters. The numerical simulations were based on Visual MODFLOW code. These simulations indicate that, if the actual extraction regime is maintained, the drawdown of the potentiometric surface will get worse to the SE of the study area (i. e. beneath Oaxaca city). The prevailing aquifer flow direction favors the ground water pollution by fertilizers and leakage from the sewage network (dumped to the Atoyac river). According to the numerical simulation, remediation of this situation is possible if the wells located in the neighborhood of Oaxaca City are relocated at the recharge zones (i. e. at the feet from Sierra de Juarez). This remediation scenario will allow a recovery of the drawdown of the potentiometric surface. [Spanish] Se presenta un modelo geohidrologico evolutivo 3D a corto plazo (para los anos 2001, 2005 y 2015) del acuifero somero del Valle de Etla, Oaxaca, sureste de Mexico, basado en los parametros disponibles de geologia, geofisica, geoquimica e hidrologia. Las simulaciones numericas fueron realizadas en Visual MODFLOW. Estas simulaciones indican que, si el actual regimen de extraccion es mantenido, el abatimiento de la superficie potenciometrica puede ser mayor en el SE del area de estudio (i. e. cerca de la ciudad de Oaxaca). La contaminacion por fertilizantes y por las fugas de drenaje es favorecida por la direccion de flujo imperante en el acuifero (vaciandose en el rio Atoyac). De acuerdo a las simulaciones numericas, existe una posible remediacion de este proceso, relocalizando los pozos situados en la ciudad de Oaxaca en las zonas de recarga (i. e. en las faldas de la Sierra de Juarez). Este escenario de remediacion permitiria una recuperacion en el nivel de la superficie potenciometrica.

  17. In-Situ Anaerobic Biosurfactant Production Process For Remediation Of DNAPL Contamination In Subsurface Aquifers

    Science.gov (United States)

    Albino, J. D.; Nambi, I. M.

    2009-12-01

    Microbial Enhanced Oil Recovery (MEOR) and remediation of aquifers contaminated with hydrophobic contaminants require insitu production of biosurfactants for mobilization of entrapped hydrophobic liquids. Most of the biosurfactant producing microorganisms produce them under aerobic condition and hence surfactant production is limited in subsurface condition due to lack of oxygen. Currently bioremediation involves expensive air sparging or excavation followed by exsitu biodegradation. Use of microorganisms which can produce biosurfactants under anaerobic conditions can cost effectively expedite the process of insitu bioremediation or mobilization. In this work, the feasibility of anaerobic biosurfactant production in three mixed anaerobic cultures prepared from groundwater and soil contaminated with chlorinated compounds and municipal sewage sludge was investigated. The cultures were previously enriched under complete anaerobic conditions in the presence of Tetrachloroethylene (PCE) for more than a year before they were studied for biosurfactant production. Biosurfactant production under anaerobic conditions was simulated using two methods: i) induction of starvation in the microbial cultures and ii) addition of complex fermentable substrates. Positive result for biosurfactant production was not observed when the cultures were induced with starvation by adding PCE as blobs which served as the only terminal electron acceptor. However, slight reduction in interfacial tension was noticed which was caused by the adherence of microbes to water-PCE interface. Biosurfactant production was observed in all the three cultures when they were fed with complex fermentable substrates and surface tension of the liquid medium was lowered below 35 mN/m. Among the fermentable substrates tested, vegetable oil yielded highest amount of biosurfactant in all the cultures. Complete biodegradation of PCE to ethylene at a faster rate was also observed when vegetable oil was amended to the

  18. Aquifers

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This map layer contains the shallowest principal aquifers of the conterminous United States, Hawaii, Puerto Rico, and the U.S. Virgin Islands, portrayed as polygons....

  19. An economic decision framework using modeling for improving aquifer remediation design

    International Nuclear Information System (INIS)

    James, B.R.; Gwo, J.P.; Toran, L.E.

    1995-11-01

    Reducing cost is a critical challenge facing environmental remediation today. One of the most effective ways of reducing costs is to improve decision-making. This can range from choosing more cost- effective remediation alternatives (for example, determining whether a groundwater contamination plume should be remediated or not) to improving data collection (for example, determining when data collection should stoop). Uncertainty in site conditions presents a major challenge for effective decision-making. We present a framework for increasing the effectiveness of remedial design decision-making at groundwater contamination sites where there is uncertainty in many parameters that affect remediation design. The objective is to provide an easy-to-use economic framework for making remediation decisions. The presented framework is used to 1) select the best remedial design from a suite of possible ones, 2) estimate if additional data collection is cost-effective, and 3) determine the most important parameters to be sampled. The framework is developed by combining elements from Latin-Hypercube simulation of contaminant transport, economic risk-cost-benefit analysis, and Regional Sensitivity Analysis (RSA)

  20. An economic decision framework using modeling for improving aquifer remediation design

    Energy Technology Data Exchange (ETDEWEB)

    James, B.R.; Gwo, J.P.; Toran, L.E.

    1995-11-01

    Reducing cost is a critical challenge facing environmental remediation today. One of the most effective ways of reducing costs is to improve decision-making. This can range from choosing more cost- effective remediation alternatives (for example, determining whether a groundwater contamination plume should be remediated or not) to improving data collection (for example, determining when data collection should stoop). Uncertainty in site conditions presents a major challenge for effective decision-making. We present a framework for increasing the effectiveness of remedial design decision-making at groundwater contamination sites where there is uncertainty in many parameters that affect remediation design. The objective is to provide an easy-to-use economic framework for making remediation decisions. The presented framework is used to 1) select the best remedial design from a suite of possible ones, 2) estimate if additional data collection is cost-effective, and 3) determine the most important parameters to be sampled. The framework is developed by combining elements from Latin-Hypercube simulation of contaminant transport, economic risk-cost-benefit analysis, and Regional Sensitivity Analysis (RSA).

  1. Application of Fe-Cu/Biochar System for Chlorobenzene Remediation of Groundwater in Inhomogeneous Aquifers

    OpenAIRE

    Xu Zhang; Yanqing Wu; Pingping Zhao; Xin Shu; Qiong Zhou; Zichen Dong

    2017-01-01

    Chlorobenzene (CB), as a typical Volatile Organic Contaminants (VOC), is toxic, highly persistent and easily migrates in water, posing a significant risk to human health and subsurface ecosystems. Therefore, exploring effective approaches to remediate groundwater contaminated by CB is essential. As an enhanced micro-electrolysis system for CB-contaminated groundwater remediation, this study attempted to couple the iron-copper bimetal with biochar. Two series of columns using sands with differ...

  2. Electrokinetically Enhanced Delivery for ERD Remediation of Chlorinated Ethenes in a Fractured Limestone Aquifer

    DEFF Research Database (Denmark)

    Broholm, Mette Martina; Hyldegaard, Bente Højlund; With Nedergaard, Lærke

    Leakage of the chlorinated solvents PCE and TCE into limestone aquifers from contaminated overburden and the long-lasting back diffusion from the secondary source in the limestone matrix pose a severe risk for contamination of drinking water resources. Dechlorination of PCE and TCE in limestone...... that enhanced reductive dechlorination (ERD) by the addition of donor and specific degraders (KB1® culture) can lead to complete dechlorination of PCE and TCE in the limestone aquifer, provided sufficient contact between specific degraders, donor and specific degraders, is obtained. Advection-based delivery...

  3. Use of high performance computing to examine the effectiveness of aquifer remediation

    International Nuclear Information System (INIS)

    Tompson, A.F.B.; Ashby, S.F.; Falgout, R.D.; Smith, S.G.; Fogwell, T.W.; Loosmore, G.A.

    1994-06-01

    Large-scale simulation of fluid flow and chemical migration is being used to study the effectiveness of pump-and-treat restoration of a contaminated, saturated aquifer. A three-element approach focusing on geostatistical representations of heterogeneous aquifers, high-performance computing strategies for simulating flow, migration, and reaction processes in large three-dimensional systems, and highly-resolved simulations of flow and chemical migration in porous formations will be discussed. Results from a preliminary application of this approach to examine pumping behavior at a real, heterogeneous field site will be presented. Future activities will emphasize parallel computations in larger, dynamic, and nonlinear (two-phase) flow problems as well as improved interpretive methods for defining detailed material property distributions

  4. Surfactant-enhanced flushing enhances colloid transport and alters macroporosity in diesel-contaminated soil.

    Science.gov (United States)

    Guan, Zhuo; Tang, Xiang-Yu; Nishimura, Taku; Katou, Hidetaka; Liu, Hui-Yun; Qing, Jing

    2018-02-01

    Soil contamination by diesel has been often reported as a result of accidental spillage, leakage and inappropriate use. Surfactant-enhanced soil flushing is a common remediation technique for soils contaminated by hydrophobic organic chemicals. In this study, soil flushing with linear alkylbenzene sulfonates (LAS, an anionic surfactant) was conducted for intact columns (15cm in diameter and 12cm in length) of diesel-contaminated farmland purple soil aged for one year in the field. Dynamics of colloid concentration in column outflow during flushing, diesel removal rate and resulting soil macroporosity change by flushing were analyzed. Removal rate of n-alkanes (representing the diesel) varied with the depth of the topsoil in the range of 14%-96% while the n-alkanes present at low concentrations in the subsoil were completely removed by LAS-enhanced flushing. Much higher colloid concentrations and larger colloid sizes were observed during LAS flushing in column outflow compared to water flushing. The X-ray micro-computed tomography analysis of flushed and unflushed soil cores showed that the proportion of fine macropores (30-250μm in diameter) was reduced significantly by LAS flushing treatment. This phenomenon can be attributed to enhanced clogging of fine macropores by colloids which exhibited higher concentration due to better dispersion by LAS. It can be inferred from this study that the application of LAS-enhanced flushing technique in the purple soil region should be cautious regarding the possibility of rapid colloid-associated contaminant transport via preferential pathways in the subsurface and the clogging of water-conducting soil pores. Copyright © 2017. Published by Elsevier B.V.

  5. BENCH-SCALE VISUALIZATION OF DNAPL REMEDIATION PROCESSES IN ANALOG HETEROGENEOUS AQUIFERS: SURFACTANT FLOODS, AND IN SITU OXIDATION USING PERMANGANATE

    Science.gov (United States)

    We have conducted well-controlled DNAPL remediation experiments using surfactants (Aerosol MA and Tween 80) to increase solubility and an oxidant (permanganate) to chemically degrade the DNAPL. Photographs and digital image analysis illustrate previously unobserved interactions b...

  6. Surfactant-enhanced alkaline flooding for light oil recovery. Annual report, 1992--1993

    Energy Technology Data Exchange (ETDEWEB)

    Wasan, D.T.

    1994-08-01

    In this report, the authors present the results of experimental and theoretical studies in surfactant-enhanced alkaline flooding for light oil recovery. The overall objective of this work is to develop a very cost-effective method for formulating a successful surfactant-enhanced alkaline flood by appropriately choosing mixed alkalis which form inexpensive buffers to obtain the desired pH (between 8.5 and 12.0) for ultimate spontaneous emulsification and ultralow interfacial tension. In addition, the authors have (1) developed a theoretical interfacial activity model for determining equilibrium interfacial tension, (2) investigated the mechanisms for spontaneous emulsification, (3) developed a technique to monitor low water content in oil, and (4) developed a technique to study water-in-oil emulsion film properties.

  7. CHROTRAN 1.0. A mathematical and computational model for in situ heavy metal remediation in heterogeneous aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Scott K.; Pandey, Sachin; Karra, Satish; Vesselinov, Velimir V. [Los Alamos National Laboratory, Los Alamos, NM (United States). Computational Earth Science Group (EES-16)

    2017-07-01

    Groundwater contamination by heavy metals is a critical environmental problem for which in situ remediation is frequently the only viable treatment option. For such interventions, a multi-dimensional reactive transport model of relevant biogeochemical processes is invaluable. To this end, we developed a model, chrotran, for in situ treatment, which includes full dynamics for five species: a heavy metal to be remediated, an electron donor, biomass, a nontoxic conservative bio-inhibitor, and a biocide. Direct abiotic reduction by donor-metal interaction as well as donor-driven biomass growth and bio-reduction are modeled, along with crucial processes such as donor sorption, bio-fouling, and biomass death. Our software implementation handles heterogeneous flow fields, as well as arbitrarily many chemical species and amendment injection points, and features full coupling between flow and reactive transport. We describe installation and usage and present two example simulations demonstrating its unique capabilities. One simulation suggests an unorthodox approach to remediation of Cr(VI) contamination.

  8. CHROTRAN 1.0: A mathematical and computational model for in situ heavy metal remediation in heterogeneous aquifers

    Science.gov (United States)

    Hansen, Scott K.; Pandey, Sachin; Karra, Satish; Vesselinov, Velimir V.

    2017-12-01

    Groundwater contamination by heavy metals is a critical environmental problem for which in situ remediation is frequently the only viable treatment option. For such interventions, a multi-dimensional reactive transport model of relevant biogeochemical processes is invaluable. To this end, we developed a model, text smallcaps">chrotran, for in situ treatment, which includes full dynamics for five species: a heavy metal to be remediated, an electron donor, biomass, a nontoxic conservative bio-inhibitor, and a biocide. Direct abiotic reduction by donor-metal interaction as well as donor-driven biomass growth and bio-reduction are modeled, along with crucial processes such as donor sorption, bio-fouling, and biomass death. Our software implementation handles heterogeneous flow fields, as well as arbitrarily many chemical species and amendment injection points, and features full coupling between flow and reactive transport. We describe installation and usage and present two example simulations demonstrating its unique capabilities. One simulation suggests an unorthodox approach to remediation of Cr(VI) contamination.

  9. Results of the reactant sand-fracking pilot test and implications for the in situ remediation of chlorinated VOCs and metals in deep and fractured bedrock aquifers.

    Science.gov (United States)

    Marcus, D L; Bonds, C

    1999-08-12

    Permeable reactive barriers (PRBs), such as the Waterloo Funnel and Gate System, first implemented at Canadian Forces Borden facility in 1992, are a passive remediation technology capable of controlling the migration of, and treating contaminated groundwater in situ. Most of the PRBs installed to date have been shallow installations created by backfilling sheet-pile shored excavations with iron filing reactive media. More recently continuous trenchers [R. Puls, Installation of permeable reactive barriers using continuous trenching equipment, Proceedings of the RTDF Permeable Barriers Work Group, Virginia Beach, VA, September 1997] and Caissons [J. Vogan, Caisson installation of a pilot scale, permeable reactive barrier in situ treatment zone at the Sommersworth Landfill, NH, Presented to the RTDF Permeable Barriers Work Group, Alexandria, VA, April 1996], and vertical fracturing emplacements [G. Hocking, Vertical hydraulic fracture emplacement of permeable reactive barriers, Progress Report delivered to the Permeable Reactive Barriers Workgroup of the Remedial Technology Development Forum, Beaverton, OR, April 1998] have been used to create reactive barriers in soil. None of the prior methods are capable of adequately addressing groundwater contamination in deep and fractured bedrock aquifers. The purpose of the RSF pilot study was to install reactive media into an impacted bedrock aquifer, and to evaluate the effectiveness of in situ treatment of chlorinated volatile organic compounds (CVOCs) and metals in that type of aquifer. Three discrete fractures were identified and treated and were subjected to testing before and after treatment. Between 300 and 1700 lb. of 1 mm diameter reactive proppants were injected into each zone to facilitate treatment. Monitoring data obtained from adjacent observation wells verified that fracking fluids reached at least 42 ft from the treatment well following hydrofracturing. The concentrations of many of the CVOCs decreased up to

  10. Surfactant-enhanced alkaline flooding for light oil recovery. Final report 1994--1995

    Energy Technology Data Exchange (ETDEWEB)

    Wasan, D.T.

    1995-12-01

    In this report, the authors present the results of their experimental and theoretical studies in surfactant-enhanced alkaline flooding for light oil recovery. The overall objective of this work is to develop a very cost-effective method for formulating a successful surfactant-enhanced alkaline flood by appropriately choosing mixed alkalis which form inexpensive buffers to obtain the desired pH (between 8.5 and 12.0) for ultimate spontaneous emulsification and ultralow interfacial tension. In addition, the authors have (1) developed a theoretical interfacial activity model for determining equilibrium interfacial tension, (2) investigated the mechanisms for spontaneous emulsification, (3) developed a technique to monitor low water content in oil, and (4) developed a technique to study water-in-oil emulsion film properties, (5) investigated the effect of surfactant on the equilibrium and transient interfacial tension, (6) investigated the kinetics of oil removal from a silica surface, and (7) developed a theoretical interfacial activity model for determining equilibrium interfacial tension, accounting for added surfactant. The results of the studies conducted during the course of this project are summarized.

  11. Surfactant-enhanced alkaline flooding for light oil recovery. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wasan, D.T.

    1996-05-01

    In this report, we present the results of our experimental and theoretical studies in surfactant-enhanced alkaline flooding for light oil recovery. The overall objective of this work is to develop a very cost-effective method for formulating a successful surfactant-enhanced alkaline flood by appropriately choosing mixed alkalis which form inexpensive buffers to obtain the desired pH (between 8.5 and 12. 0) for ultimate spontaneous emulsification and ultralow interfacial tension. In addition, we have (1) developed a theoretical interfacial activity model for determining equilibrium interfacial tension, (2) investigated the mechanisms for spontaneous emulsification, (3) developed a technique to monitor low water content in oil and (4) developed a technique to study water-in-oil emulsion film properties, (5) investigated the effect of surfactant on the equilibrium and transient interfacial tension, (6) investigated the kinetics of oil removal from a silica surface, and (7) developed a theoretical interfacial activity model for determining equilibrium interfacial tension, accounting for added surfactant. The results of the studies conducted during the course of this project are discussed.

  12. Field Test Report: Preliminary Aquifer Test Characterization Results for Well 299-W15-225: Supporting Phase I of the 200-ZP-1 Groundwater Operable Unit Remedial Design

    Energy Technology Data Exchange (ETDEWEB)

    Spane, Frank A.; Newcomer, Darrell R.

    2009-09-23

    This report examines the hydrologic test results for both local vertical profile characterization and large-scale hydrologic tests associated with a new extraction well (well 299-W15-225) that was constructed during FY2009 for inclusion within the future 200-West Area Groundwater Treatment System that is scheduled to go on-line at the end of FY2011. To facilitate the analysis of the large-scale hydrologic test performed at newly constructed extraction well 299-W15-225 (C7017; also referred to as EW-1 in some planning documents), the existing 200-ZP-1 interim pump-and-treat system was completely shut-down ~1 month before the performance of the large-scale hydrologic test. Specifically, this report 1) applies recently developed methods for removing barometric pressure fluctuations from well water-level measurements to enhance the detection of hydrologic test and pump-and-treat system effects at selected monitor wells, 2) analyzes the barometric-corrected well water-level responses for a preliminary determination of large-scale hydraulic properties, and 3) provides an assessment of the vertical distribution of hydraulic conductivity in the vicinity of newly constructed extraction well 299-W15-225. The hydrologic characterization approach presented in this report is expected to have universal application for meeting the characterization needs at other remedial action sites located within unconfined and confined aquifer systems.

  13. Simulated flow of groundwater and brine from a flooded salt mine in Livingston County, New York, and effects of remedial pumping on an overlying aquifer

    Science.gov (United States)

    Yager, Richard M.; Miller, Todd S.; Kappel, William M.; Misut, Paul E.; Langevin, Christian D.; Parkhurst, David L.; deVries, M. Peter

    2012-01-01

    Two ceiling collapses in the Retsof salt mine near Geneseo in upstate New York in spring 1994 resulted in the upward propagation of two columns of rubble through 600 feet of overlying shale and carbonate bedrock. This upward propagation formed a hydraulic connection between the lower confined aquifer (LCA) and the mine and allowed water from the aquifer and bedrock fracture zones that intersected the rubble columns to flow into the mine at a rate of 18,000 gallons per minute (gal/min) . All salt mining ceased in September 1995, and the mine was completely flooded by January 1996. The flow of water from the lower confined aquifer into the mine caused widespread drawdowns, and water levels in the aquifer declined by as much as 400 feet near the collapse area and by more than 50 feet at wells 7 miles to the north and south. Within 3 to 4 weeks of the collapses, water levels in about a dozen domestic and industrial wells had declined severely, and some wells went dry. Water levels in at least 58 wells in the lower and middle confined aquifers were affected by mine flooding. Groundwater in the upper unconfined aquifer and surface water in streams were unaffected by water-level drawdown, but channels of the Genesee River and Beards Creek were altered by land subsidence related to the mine collapse. Water levels recovered from 1996 through 2006, but the mine is now filled with about 15 billion gallons of saturated halite brine. The weight of the overlying rock and sediment is expected to cause the salt beds to deform and fill the mine cavity during the next several hundred years; this in turn could displace as much as 80 percent of the brine and cause it to move upward through the rubble chimneys, rendering the LCA unusable as a source of water supply. Saline water was detected in the LCA in 2002 but was found to be derived primarily from fractures in the limestone and shale units between the mine and the LCA, rather than from the mine. In September 2006, the mine company

  14. Surfactant-Enhanced Size-Excluded Transport of Bacteria Through Unsaturated Porous Media.

    Science.gov (United States)

    Zhu, J.

    2017-12-01

    US domestic waste water is rich in surfactants because of the intensive usage of surfactants-containing household product. It results in a surfactants presence environment when this untreated waste water released into subsurface. It was reported that surfactants enhance the colloidal transport in porous media, which have significant effect on issues such as subsurface pathogens contamination and biodegradation. In this study, soil column experiments were conducted. The soil column was remained unsaturated and with a steady flow passing through it. Escherichia coli K-12 transported in the soil column and its breakthrough data was collected in presence of surfactant anionic surfactant linear alkylbenzene sulfonate (LAS) concentration range over 0, 0.25, 0.5, 0.75, 1, and 2 times Critical Micelle Concentration (CMC). It was found that the increase in LAS concentration greatly increases breakthrough concentration C/C0 and decreases breakthrough time tb until LAS concentration reaches 1 xCMC. Numerical models were built simulating and investigating this phenomenon. The goodness of model fitting was greatly improved by adding exclusion factor into the model, which indicated that the presence of surfactant might enhance the exclusion effect. The relationships between LAS concentration and the two coefficients, deposition rate coefficient k and exclusion effect coefficient θim, were found can be fitted by a quasi-Langmuir equation. And the model validation with observed data showed that the model has an acceptable reliability.

  15. Practical Considerations and Challenges Involved in Surfactant Enhanced Bioremediation of Oil

    Science.gov (United States)

    Mohanty, Sagarika; Jasmine, Jublee

    2013-01-01

    Surfactant enhanced bioremediation (SEB) of oil is an approach adopted to overcome the bioavailability constraints encountered in biotransformation of nonaqueous phase liquid (NAPL) pollutants. Fuel oils contain n-alkanes and other aliphatic hydrocarbons, monoaromatics, and polynuclear aromatic hydrocarbons (PAHs). Although hydrocarbon degrading cultures are abundant in nature, complete biodegradation of oil is rarely achieved even under favorable environmental conditions due to the structural complexity of oil and culture specificities. Moreover, the interaction among cultures in a consortium, substrate interaction effects during the degradation and ability of specific cultures to alter the bioavailability of oil invariably affect the process. Although SEB has the potential to increase the degradation rate of oil and its constituents, there are numerous challenges in the successful application of this technology. Success is dependent on the choice of appropriate surfactant type and dose since the surfactant-hydrocarbon-microorganism interaction may be unique to each scenario. Surfactants not only enhance the uptake of constituents through micellar solubilization and emulsification but can also alter microbial cell surface characteristics. Moreover, hydrocarbons partitioned in micelles may not be readily bioavailable depending on the microorganism-surfactant interactions. Surfactant toxicity and inherent biodegradability of surfactants may pose additional challenges as discussed in this review. PMID:24350261

  16. The application of a mulch biofilm barrier for surfactant enhanced polycyclic aromatic hydrocarbon bioremediation

    International Nuclear Information System (INIS)

    Seo, Youngwoo; Lee, Woo-Hyung; Sorial, George; Bishop, Paul L.

    2009-01-01

    Lab scale mulch biofilm barriers were constructed and tested to evaluate their performance for preventing the migration of aqueous and surfactant solubilized PAHs. The spatial distribution of viable PAH degrader populations and resultant biofilm formation were also monitored to evaluate the performance of the biobarrier and the prolonged surfactant effect on the PAH degrading microorganism consortia in the biobarrier. Sorption and biodegradation of PAHs resulted in stable operation of the system for dissolved phenanthrene and pyrene during 150 days of experimentation. The nonionic surfactant could increase the solubility of phenanthrene and pyrene significantly. However, the biobarrier itself couldn't totally prevent the migration of micellar solubilized phenanthrene and pyrene. The presence of surfactant and the resultant highly increased phenanthrene or pyrene concentration didn't appear to cause toxic effects on the attached biofilm in the biobarrier. However, the presence of surfactant did change the structural composition of the biofilm. - Mulch biofilm barrier showed potential for surfactant enhanced bioremediation, and the presence of surfactant changed the structural composition of the biofilm

  17. Surfactant-enhanced recovery of dissolved hydrocarbons at petroleum production facilities

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, J.T.; Mayes, M. [Groundwater Solutions Ltd., Calgary, AB (Canada); Wassmuth, F.; Taylor, K. [Petroleum Recovery Inst., Calgary, AB (Canada); Rae, W. [Chemex Labs. (Alberta) Ltd., Calgary, AB (Canada); Kuipers, F. [Pembina Corp., Calgary, AB (Canada)

    1997-12-31

    The feasibility and cost effectiveness of surfactant-enhanced pumping to reduce source concentrations of petroleum hydrocarbons from contaminated soils was discussed. Light non-aqueous phase liquids (LNAPL) hydrocarbons are present beneath many petroleum production processing facilities in western Canada. Complete removal of LNAPLs from geologic materials is difficult and expensive. Treatment technologies include costly ex-situ methods such as excavation and in-situ methods such as physical extraction by soil venting and pumping, bioremediation, and combination methods such as bioventing, bioslurping or air sparging. Surfactant-aided pumping can reduce source hydrocarbon concentrations when used in conjunction with traditional pump and treat, or deep well injection. This study involved the selection of an appropriate surfactant from a wide variety of commercially available products. A site contaminated by hydrocarbons in Turner Valley, Alberta, was used for field scale testing. One of the major problems was quantifying the increase in the dissolved hydrocarbon concentrations in the recovered water once a surfactant was added. From the 30 surfactants screened in a series of washing and oil solubilization tests, two surfactants, Brij 97 and Tween 80, were selected for further evaluation. Increased hydrocarbon recovery was observed within 10 days of the introduction of the first surfactant. 2 refs., 7 figs.

  18. Surfactant-Enhanced Desorption and Biodegradation of Polycyclic Aromatic Hydrocarbons in Contaminated Soil

    Science.gov (United States)

    Zhu, Hongbo; Aitken, Michael D.

    2010-01-01

    We evaluated two nonionic surfactants, one hydrophobic (Brij 30) and one hydrophilic (C12E8), for their ability to enhance the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil after it had been treated in an aerobic bioreactor. The effects of each surfactant were evaluated at doses corresponding to equilibrium aqueous-phase concentrations well above the surfactant’s critical micelle concentration (CMC), slightly above the CMC, and below the CMC. The concentrations of all 3- and 4-ring PAHs were significantly lower in the soil amended with Brij 30 at the two lower doses compared to controls, whereas removal of only the 3-ring PAHs was significantly enhanced at the highest Brij 30 dose. In contrast, C12E8 did not enhance PAH removal at any dose. In the absence of surfactant, surfactants on PAH biodegradation could be explained by their effects on PAH bioavailability. Overall, this study demonstrates that the properties of the surfactant and its dose relative to the corresponding aqueous-phase concentration are important factors in designing systems for surfactant-enhanced bioremediation of PAH-contaminated soils in which PAH bioavailability is limited. PMID:20586488

  19. Aquifer Characteristics Data Report for the Weldon Spring Site chemical plant/raffinate pits and vicinity properties for the Weldon Spring Site Remedial Action Project, Weldon Spring, Missouri

    International Nuclear Information System (INIS)

    1990-11-01

    This report describes the procedures and methods used, and presents the results of physical testing performed, to characterize the hydraulic properties of the shallow Mississippian-Devonian aquifer beneath the Weldon Spring chemical plant, raffinate pits, and vicinity properties. The aquifer of concern is composed of saturated rocks of the Burlington-Keokuk Limestone which constitutes the upper portion of the Mississippian-Devonian aquifer. This aquifer is a heterogeneous anisotropic medium which can be described in terms of diffuse Darcian flow overlain by high porosity discrete flow zones and conduits. Average hydraulic conductivity for all wells tested is 9.6E-02 meters/day (3.1E-01 feet/day). High hydraulic conductivity values are representative of discrete flow in the fractured and weathered zones in the upper Burlington-Keokuk Limestone. They indicate heterogeneities within the Mississippian-Devonian aquifer. Aquifer heterogeneity in the horizontal plane is believed to be randomly distributed and is a function of fracture spacing, solution voids, and preglacial weathering phenomena. Relatively high hydraulic conductivities in deeper portions of the aquifer are though to be due to the presence of widely spaced fractures. 44 refs., 27 figs., 9 tabs

  20. Alluvial Aquifer

    Data.gov (United States)

    Kansas Data Access and Support Center — This coverage shows the extents of the alluvial aquifers in Kansas. The alluvial aquifers consist of unconsolidated Quaternary alluvium and contiguous terrace...

  1. Shifts in microbial community structure during in situ surfactant-enhanced bioremediation of polycyclic aromatic hydrocarbon-contaminated soil.

    Science.gov (United States)

    Wang, Lingwen; Li, Feng; Zhan, Yu; Zhu, Lizhong

    2016-07-01

    This study aims to reveal the microbial mechanism of in situ surfactant-enhanced bioremediation (SEBR). Various concentrations of rhamnolipids, Tween 80, and sodium dodecyl benzenesulfonate (SDBS) were separately sprayed onto soils contaminated with polycyclic aromatic hydrocarbons (PAHs) for years. Within 90 days, the highest level of degradation (95 %) was observed in the soil treated with rhamnolipids (10 mg/kg), followed by 92 % degradation with Tween 80 (50 mg/kg) and 90 % degradation with SDBS (50 mg/kg). The results of the microbial phospholipid fatty acids (PLFAs) suggest that bacteria dominated the enhanced PAH biodegradation (94 % of the maximum contribution). The shift of bacterial community structure during the surfactant treatment was analyzed by using the 16S rRNA gene high-throughput sequencing. In the presence of surfactants, the number of the operational taxonomic units (OTUs) associated with Bacillus, Pseudomonas, and Sphingomonas increased from 2-3 to 15-30 % at the end of the experiment (two to three times of control). Gene prediction with phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) shows that the PAH-degrading genes, such as 1-hydroxy-2-naphthoate dioxygenase and PAH dioxygenase large subunit, significantly increased after the surfactant applications (p < 0.05). The findings of this study provide insights into the surfactant-induced shifts of microbial community, as well as critical factors for efficient bioremediation.

  2. Risk assessment and management of an oil contaminated aquifer

    International Nuclear Information System (INIS)

    Braxein, A.; Daniels, H.; Rouve, G.; Rubin, H.

    1991-01-01

    This paper concerns the provision of the basic information needed for the decision making process regarding the remedial measures leading to reutilization of an oil contaminated aquifer. The study refers to the case history of jet fuel contamination of an aquifer comprising part of the coastal aquifer of Israel. Due to that contamination two major water supply wells were abandoned. This study examines the use of numerical simulations in order to restore the contamination history of the aquifer. Such simulations also provide quantitative information needed for the decision making process regarding the future management of the contaminated aquifer

  3. Aquifer Sampling Tube Results for Fiscal Year 2003

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, Mary J.; Peterson, Robert E.

    2003-10-27

    This report presents and discusses results of the fiscal year 2003 sampling event associated with aquifer tubes along the Columbia River in the northern Hanford Site. Aquifer tube data help define the extent of groundwater contamination near the river, determine vertical variations in contamination, monitor the performance of interim remedial actions near the river, and support impact studies.

  4. Guarani aquifer

    International Nuclear Information System (INIS)

    2007-01-01

    The environmental protection and sustain ability develop project of Guarani Aquifer System is a join work from Argentina, Brazil, Paraguay and Uruguay with a purpose to increase the knowledge resource and propose technical legal and organizational framework for sustainable management between countries.The Universities funds were created as regional universities support in promotion, training and academic research activities related to environmental al social aspects of the Guarani Aquifer System.The aim of the project is the management and protection of the underground waters resources taking advantage and assesment for nowadays and future generations

  5. Genealogy Remediated

    DEFF Research Database (Denmark)

    Marselis, Randi

    2007-01-01

    Genealogical websites are becoming an increasingly popular genre on the Web. This chapter will examine how remediation is used creatively in the construction of family history. While remediation of different kinds of old memory materials is essential in genealogy, digital technology opens new...

  6. Vortex-assisted surfactant-enhanced emulsification liquid-liquid microextraction for the determination of carbamates in juices by micellar electrokinetic chromatography tandem mass spectrometry.

    Science.gov (United States)

    Moreno-González, David; Huertas-Pérez, José F; García-Campaña, Ana M; Gámiz-Gracia, Laura

    2015-07-01

    A new method based on vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction has been developed for the extraction of carbamate pesticides in juice samples prior to their determination by micellar electrokinetic chromatography coupled to tandem mass spectrometry. This sample treatment allowed the satisfactory extraction and the extract clean-up of 25 carbamates from different fruit and vegetal juices (banana, tomato, and peach). In this study, the addition of ammonium perfluorooctanoate in the aqueous sample in combination with vortex agitation, provided very clean extracts with short extraction times. Under optimized conditions, recoveries of the proposed method for these pesticides from fortified juice samples ranged from 81% to 104%, with relative standard deviations lower than 15%. Limits of quantification were between 2.3µgkg(-)(1) and 4.7µgkg(-)(1), showing the high sensitivity of this fast and simple method. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Ultrasound-assisted surfactant-enhanced emulsification microextraction for the determination of carbamates in wines by ultra-high performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Moreno-González, David; Huertas-Pérez, José F; García-Campaña, Ana M; Bosque-Sendra, Juan M; Gámiz-Gracia, Laura

    2013-11-08

    A new sensitive multiresidue method based on ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) has been developed for the detection, confirmation and quantification of twenty five carbamates in wine samples. The separation was achieved in 5.5 min, using a Zorbax Eclipse plus RRHD C18 column (50 mm×2.1 mm, 1.8 μm), with a mobile phase of water and methanol, both of them with 0.01% formic acid. The analytes were detected in positive mode with multiple reaction monitoring mode. Ultrasound-assisted surfactant-enhanced emulsification microextraction (UASEME), using a low-density extraction solvent has been optimized for the satisfactory extraction of carbamates and clean-up of extracts. The matrix effect was studied, showing that the proposed procedure provides very clean extracts. Under optimum conditions, recoveries for fortified wine samples ranged from 74 to 102%, with relative standard deviations lower than 6%. Limits of quantification ranged from 0.15 to 0.92 μgl(-1), showing the high sensitivity of this fast and simple method and its compliance with current requirements. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Binary-solvent-based ionic-liquid-assisted surfactant-enhanced emulsification microextraction for the determination of four fungicides in apple juice and apple vinegar.

    Science.gov (United States)

    Chen, Xiaochu; Zhang, Xu; Liu, Fengmao; Hou, Fan

    2017-02-01

    A binary-solvent-based ionic-liquid-assisted surfactant-enhanced emulsification microextraction method was developed for the separation/preconcentration and determination of four fungicides (pyrimethanil, fludioxonil, cyprodynil, pyraclostrobin) in apple juice and apple vinegar. A nonchlorinated solvent amyl acetate, which has a lower density than water, was used as the extraction solvent, and an ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate, which has a high density and low toxicity, was used as a secondary solvent mixed with the extraction solvent. After centrifugation, the binary solvent drop with a relatively high density was deposited on the bottom of the tube. Some parameters influencing the extraction efficiency of analytes such as type of extraction solvent, ratio of ionic liquid, volume of mixed solvent, type and concentration of surfactant, sample pH, NaCl concentration, and vortex time were investigated and optimized. Under the optimized conditions, the proposed method provided a good linearity in the range of 5-200 μg/L. The limits of quantification of the method were in the range of 2-5 μg/L. The relative standard deviations for interday assays were 1.7-11.9%. The method was applied to the determination of pyrimethanil, fludioxonil, cyprodynil, and pyraclostrobin in apple juice and apple vinegar samples, and the accuracy was evaluated through recovery experiments. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Dual Pump Recovery (DPR System to Extract Freshwater in Coastal Aquifers

    Directory of Open Access Journals (Sweden)

    C. Otto

    2002-06-01

    Full Text Available The paper describes the hydraulic theory of recovering a dense plume using a newly devised dual pump recover system (DPR and its feasibility to half the remediation time of a contaminated unconfined aquifer in a coastal urban environment. Although the DPR system was successfully applied to clean up the polluted aquifer, the hydraulic principles and techniques are also applicable to extract fresh groundwater from coastal aquifers without the risk of saltwater incursion.

  10. Enhanced Amendment Delivery to Overcome Subsurface Physical Remediation Barriers

    Science.gov (United States)

    Zhong, L.; Truex, M. J.; Oostrom, M.; Szecsody, J. E.; Vermeul, V.; Li, X.

    2013-12-01

    Waste discharges can result in contamination of the unsaturated zone (vadose zone) and the water saturated zone (aquifer). To restore the environment, many in situ remediation technologies rely on delivery of remedial reagents (amendments) to the subsurface that treat or help remove contamination. However, through numerous remediation applications, the remediation industry has recognized that a major issue with in situ remediation is the difficulty in achieving an even spatial distribution of remedial amendments to the contamination zones in an aquifer or in the vadose zone. Poor amendment delivery leads to ineffective environmental restoration because some of the contaminants are not contacted by the amendment and, therefore, not treated or removed. This challenge often leads to a failure in environment restoration. Researches are being conducted to develop enhanced remediation amendment delivery approaches using shear thinning fluids (STFs) for aquifer and aqueous foams for vadose zone. STFs have properties that promote more uniform delivery of injected solutions so that amendments are able to reach low-permeability zones in an aquifer. These low-permeability zones are most difficult to reach with conventional delivery approaches, yet often contain the high contamination concentrations. Foam delivery is targeted for distribution of aqueous, gaseous amendments, and remedial nano-particles to the vadose zone. Foam transport in the vadose zone provides significant advantages for lateral distribution of amendments compared to aqueous-phase transport, improves uniformity of distribution compared to both aqueous- and gas-phase injection, and enables delivery of a broader range of remediation amendments than can be delivered in the gas phase.

  11. Determination of melamine in soil samples using surfactant-enhanced hollow fiber liquid phase microextraction followed by HPLC–UV using experimental design

    Directory of Open Access Journals (Sweden)

    Ali Sarafraz Yazdi

    2015-11-01

    Full Text Available Surfactant-enhanced hollow fiber liquid phase (SE-HF-LPME microextraction was applied for the extraction of melamine in conjunction with high performance liquid chromatography with UV detection (HPLC–UV. Sodium dodecyl sulfate (SDS was added firstly to the sample solution at pH 1.9 to form hydrophobic ion-pair with protonated melamine. Then the protonated melamine–dodecyl sulfate ion-pair (Mel–DS was extracted from aqueous phase into organic phase immobilized in the pores and lumen of the hollow fiber. After extraction, the analyte-enriched 1-octanol was withdrawn into the syringe and injected into the HPLC. Preliminary, one variable at a time method was applied to select the type of extraction solvent. Then, in screening step, the other variables that may affect the extraction efficiency of the analyte were studied using a fractional factorial design. In the next step, a central composite design was applied for optimization of the significant factors having positive effects on extraction efficiency. The optimum operational conditions included: sample volume, 5 mL; surfactant concentration, 1.5 mM; pH 1.9; stirring rate, 1500 rpm and extraction time, 60 min. Using the optimum conditions, the method was analytically evaluated. The detection limit, relative standard deviation and linear range were 0.005 μg mL−1, 4.0% (3 μg mL−1, n = 5 and 0.01–8 μg mL−1, respectively. The performance of the procedure in extraction of melamine from the soil samples was good according to its relative recoveries in different spiking levels (95–109%.

  12. Vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction of biogenic amines in fermented foods before their simultaneous analysis by high-performance liquid chromatography.

    Science.gov (United States)

    Donthuan, Jaruwan; Yunchalard, Sirinda; Srijaranai, Supalax

    2014-11-01

    A simple, rapid, sensitive, and environmentally friendly method, based on modified dispersive liquid-liquid microextraction coupled with high-performance liquid chromatography was developed for the simultaneous determination of five biogenic amines in fermented food samples. Biogenic amines were derivatized with 9-fluorenylmethyl chloroformate, extracted by vortex-assisted surfactant-enhanced emulsification liquid-liquid microextraction, and then analyzed by high-performance liquid chromatography. Five biogenic amine compounds were separated within 30 min using a C18 column and gradient elution with acetonitrile and 1% acetic acid. Factors influencing the derivatization and extraction efficiency such as type and volume of extraction solvent, type, and concentration of surfactant, pH, salt addition, and vortex time were optimized. Under the optimum conditions, the method provided the enrichment factors in the range of 161-553. Good linearity was obtained from 0.002-0.5 mg/L for cadaverine and tyramine, 0.003-1 mg/L for tryptamine and histamine, and 0.005-1 mg/L for spermidine with coefficient of determination (R(2) ) > 0.992. The limits of detection ranged from 0.0010 to 0.0026 mg/L. The proposed method was successfully applied to analysis of biogenic amines in fermented foods such as fermented fish (plaa-som), wine and beer where good recoveries were obtained in the range of 83.2-112.5% © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Understanding Uranium Behavior in a Reduced Aquifer

    Science.gov (United States)

    Janot, N.; Lezama-Pacheco, J. S.; Williams, K. H.; Bernier-Latmani, R.; Long, P. E.; Davis, J. A.; Fox, P. M.; Yang, L.; Giammar, D.; Cerrato, J. M.; Bargar, J.

    2012-12-01

    Uranium contamination of groundwater is a concern at several US Department of Energy sites, such Old Rifle, CO. Uranium transport in the environment is mainly controlled by its oxidation state, since oxidized U(VI) is relatively mobile, whereas U(IV) is relatively insoluble. Bio-remediation of contaminated aquifers aims at immobilizing uranium in a reduced form. Previous laboratory and field studies have shown that adding electron donor (lactate, acetate, ethanol) to groundwater stimulates the activity of metal- and sulfate-reducing bacteria, which promotes U(VI) reduction in contaminated aquifers. However, obtaining information on chemical and physical forms of U, Fe and S species for sediments biostimulated in the field, as well as kinetic parameters such as U(VI) reduction rate, is challenging due to the low concentration of uranium in the aquifers (typically uranium, iron and sulfur reduction dynamics during such bioremediation episodes. This technique uses in-well columns to obtain direct access to chemical and physical forms of U(IV) produced in the aquifer, evolving microbial communities, and trace and major ion groundwater constituents. While several studies have explored bioreduction of uranium under sulfate-reducing conditions, less attention has been paid to the initial iron-reducing phase, noted as being of particular importance to uranium removal. The aim of this work was to assess the formation of U(IV) during the early stages of a bio-remediation experiment at the Old Rifle site, CO, from early iron-reducing conditions to the transition to sulfate-reducing conditions. Several in-well chromatographic columns packed with sediment were deployed and were sampled at different days after the start of bio-reduction. X-ray absorption spectroscopy and X-ray microscopy were used to obtain information on Fe, S and U speciation and distribution. Chemical extractions of the reduced sediments have also been performed, to determine the rate of Fe(II) and U

  14. Fate and transport potential for dissolved polycyclic aromatic hydrocarbons from a shallow to a deep aquifer at the Madisonville Creosote works

    Science.gov (United States)

    Lee, R.W.; Tzhone, S.; ,

    2002-01-01

    The Remedy selected for a deep aquifer at the Madisonville Creosote Works, which have a potential threat of contamination from a nearby contaminated shallow aquifer is presented. The remedy includes monitoring, in consideration of the low permeability of the clay unit separating the two aquifers and the limited transport potential of the dissolved polycyclic aromatic hydrocarbons. A computer model was used for predication of the potential fate and transport of contaminants to the deep drinking water supply aquifer. The model results show conservative breakthrough of naphthalene from the source creosote in the shallow water bearing zone at about 150 years.

  15. Biscayne aquifer, southeast Florida

    Science.gov (United States)

    Klein, Howard; Hull, John E.

    1978-01-01

    Peak daily pumpage from the highly permeable, unconfined Biscayne aquifer for public water-supply systems in southeast Florida in 1975 was about 500 million gallons. Another 165 million gallons was withdrawn daily for irrigation. Recharge to the aquifer is primarily by local rainfall. Discharge is by evapotranspiration, canal drainage, coastal seepage, and pumping. Pollutants can enter the aquifer by direct infiltration from land surface or controlled canals, septic-tank and other drainfields, drainage wells, and solid-waste dumps. Most of the pollutants are concentrated in the upper 20 to 30 feet of the aquifer; public supply wells generally range in depth from about 75 to 150 feet. Dilution, dispersion, and adsorption tend to reduce the concentrations. Seasonal heavy rainfall and canal discharge accelerate ground-water circulation, thereby tending to dilute and flush upper zones of the aquifer. The ultimate fate of pollutants in the aquifer is the ocean, although some may be adsorbed by the aquifer materials en route to the ocean, and some are diverted to pumping wells. (Woodard-USGS)

  16. EPA Sole Source Aquifers

    Data.gov (United States)

    U.S. Environmental Protection Agency — Information on sole source aquifers (SSAs) is widely used in assessments under the National Environmental Policy Act and at the state and local level. A national...

  17. Ogallala Aquifer Mapping Program

    International Nuclear Information System (INIS)

    1984-10-01

    A computerized data file has been established which can be used efficiently by the contour-plotting program SURFACE II to produce maps of the Ogallala aquifer in 17 counties of the Texas Panhandle. The data collected have been evaluated and compiled into three sets, from which SURFACE II can generate maps of well control, aquifer thickness, saturated thickness, water level, and the difference between virgin (pre-1942) and recent (1979 to 1981) water levels. 29 figures, 1 table

  18. Topical Day on Site Remediation

    Energy Technology Data Exchange (ETDEWEB)

    Vandenhove, H. [ed.

    1996-09-18

    Ongoing activities at the Belgian Nuclear Research Centre relating to site remediation and restoration are summarized. Special attention has been paid to the different phases of remediation including characterization, impact assessment, evaluation of remediation actions, and execution of remediation actions.

  19. Topical Day on Site Remediation

    International Nuclear Information System (INIS)

    Vandenhove, H.

    1996-01-01

    Ongoing activities at the Belgian Nuclear Research Centre relating to site remediation and restoration are summarized. Special attention has been paid to the different phases of remediation including characterization, impact assessment, evaluation of remediation actions, and execution of remediation actions

  20. Colloid remediation in groundwater by polyelectrolyte capture

    International Nuclear Information System (INIS)

    Nuttall, H.E.; Rao, S.; Jain, R.

    1992-01-01

    This paper describes an ongoing study to characterize groundwater colloids, to understand the geochemical factors affecting colloid transport in groundwater, and to develop an in-situ colloid remediation process. The colloids and suspended particulate matter used in this study were collected from a perched aquifer site that has radiation levels several hundred times the natural background and where previous researchers have measured and reported the presence of radiocolloids containing plutonium and americium. At this site, radionuclides have spread over several kilometers. Inorganic colloids collected from water samples are characterized with respect to concentration, mineralogy, size distribution, electrophoretic mobility (zeta potential), and radioactivity levels. Presented are the methods used to investigate the physiochemical factors affecting colloid transport and the preliminary analytical results. Included below are a description of a colloid transport model and the corresponding computational code, water analyses, characterization of the inorganic colloids, and a conceptual description of a process for in-situ colloid remediation using the phenomenon of polyelectrolyte capture

  1. Effects of microarrangement of solid particles on PCE migration and its remediation in porous media

    Science.gov (United States)

    Wu, Ming; Wu, Jianfeng; Wu, Jichun; Hu, Bill X.

    2018-02-01

    Groundwater can be stored abundantly in granula-composed aquifers with high permeability. The microstructure of granular materials has important effect on the permeability of aquifers and the contaminant migration and remediation in aquifers is also influenced by the characteristics of porous media. In this study, two different microscale arrangements of sand particles are compared to reveal the effects of microstructure on the contaminant migration and remediation. With the help of fractal theory, the mathematical expressions of permeability and entry pressure are conducted to delineate granular materials with regular triangle arrangement (RTA) and square pitch arrangement (SPA) at microscale. Using a sequential Gaussian simulation (SGS) method, a synthetic heterogeneous site contaminated by perchloroethylene (PCE) is then used to investigate the migration and remediation affected by the two different microscale arrangements. PCE is released from an underground storage tank into the aquifer and the surfactant is used to clean up the subsurface contamination. Results suggest that RTA can not only cause more groundwater contamination, but also make remediation become more difficult. The PCE remediation efficiency of 60.01-99.78 % with a mean of 92.52 and 65.53-99.74 % with a mean of 95.83 % is achieved for 200 individual heterogeneous realizations based on the RTA and SPA, respectively, indicating that the cleanup of PCE in aquifer with SPA is significantly easier. This study leads to a new understanding of the microstructures of porous media and demonstrates how microscale arrangements control contaminant migration in aquifers, which is helpful to design successful remediation scheme for underground storage tank spill.

  2. Effects of microarrangement of solid particles on PCE migration and its remediation in porous media

    Directory of Open Access Journals (Sweden)

    M. Wu

    2018-02-01

    Full Text Available Groundwater can be stored abundantly in granula-composed aquifers with high permeability. The microstructure of granular materials has important effect on the permeability of aquifers and the contaminant migration and remediation in aquifers is also influenced by the characteristics of porous media. In this study, two different microscale arrangements of sand particles are compared to reveal the effects of microstructure on the contaminant migration and remediation. With the help of fractal theory, the mathematical expressions of permeability and entry pressure are conducted to delineate granular materials with regular triangle arrangement (RTA and square pitch arrangement (SPA at microscale. Using a sequential Gaussian simulation (SGS method, a synthetic heterogeneous site contaminated by perchloroethylene (PCE is then used to investigate the migration and remediation affected by the two different microscale arrangements. PCE is released from an underground storage tank into the aquifer and the surfactant is used to clean up the subsurface contamination. Results suggest that RTA can not only cause more groundwater contamination, but also make remediation become more difficult. The PCE remediation efficiency of 60.01–99.78 % with a mean of 92.52 and 65.53–99.74 % with a mean of 95.83 % is achieved for 200 individual heterogeneous realizations based on the RTA and SPA, respectively, indicating that the cleanup of PCE in aquifer with SPA is significantly easier. This study leads to a new understanding of the microstructures of porous media and demonstrates how microscale arrangements control contaminant migration in aquifers, which is helpful to design successful remediation scheme for underground storage tank spill.

  3. Polyphosphate Remediation Technology for In-Situ Stabilization of Uranium

    International Nuclear Information System (INIS)

    Wellman, Dawn M.; Pierce, Eric M.; Bacon, Diana H.; Fruchter, Jonathan S.; Vermeul, Vincent R.; Webb, Samuel M.

    2009-01-01

    A labortory testing program has been conducted to optimize polyphosphate remediation technology for implementation through a field-scale technology infiltration demonstration to stabilize soluble, uranium-bearing source phases in the vadose zone and capillary fringe. Source treatment in the deep vadose zone will accelerate the natural attenuation of uranium to more thermodynamically stable uranium-phosphate minerals, enhancing the performance of the proposed polyphosphate remediation within the 300 Area aquifer. The objective of this investigation was to develop polyphosphate remediation technology to treat uranium contamination contained within the deep vadose zone and capillary fringe. This paper presents the results of an investigation that evaluated the rate and extent of reaction between polyphosphate and the uranium mineral phases present within the 300 Area vadose zone and capillary fringe and autunite formation as a function of polyphosphate formulation and concentration. This information is critical for identifying the optimum implementation approach and controlling the flux of uranium from the vadose zone and capillary fringe to the underlying aquifer during remediation. Results from this investigation will be used to design a full-scale remediation of uranium at the 300 Area of the Hanford Site.

  4. Almost remediation of saltwater spills at E and P sites

    International Nuclear Information System (INIS)

    Carty, D.J.

    1995-01-01

    At exploration and production (E and P) sites crude spills restricted to topsoil are often self-remediating, but salt spills rarely are. Most soils naturally biodegrade crude. Without appropriate human intervention, brine spills can result in decades of barren land and seriously degrade surface water and aquifers. Servicing the E and P industry are remediation practitioners with a limited array of often expensive remediation concepts and materials which they hope will work, and sometimes do. Unfortunately, many remediation practitioners are unfamiliar with, or disregard, the natural physical, chemical, and biotic complexity of the soil and aquatic media. All too often this results in exacerbating injury to an already damaged ecosystem. Likewise, important cultural factors such as public relations, environmental regulations, property rights, and water rights are also overlooked until after implementation of an ill-advised or illegal remediation design has been initiated. A major issue is determining what constitutes ''successful'' remediation of a brine spill. Environmental managers have long sought one or two universally applicable fast and cheap amendment/treatment protocols for all their diverse multi-state salt affected spill scenarios. This presentation describes aspects of common spill-affected ecosystems which must be considered to achieve ''successful'' remediation

  5. Hydrologic analysis of data for the Lost Lake Aquifer Zone of the Steel Pond Aquifer at recovery well RWM-16

    International Nuclear Information System (INIS)

    Wells, D.G.; Cook, J.W.; Hiergesell, R.A.

    1993-04-01

    This report presents the results of an analysis of data obtained from a large-scale, multiple-well aquifer test of the sandy unit referred to as the Lost Lake Aquifer Zone of the Steed Pond Aquifer in an area just south of the A and M Areas. Pumping was conducted at recovery well RWM-16, which is located near the MSB-40 well cluster, approximately 4000 feet south of the M-Area Basin. RWM-16 is located in the lower left portion of Figure 1, which also illustrates the general relationship of the testing site to the A and M Areas and other monitor wells. The data generated from testing RWM-16 was used to calculate estimates of transmissivity and storage for the aquifer system within which RWM-16 is screened. These parameters are related to hydraulic conductivity and storativity of the aquifer system by the vertical thickness of the unit. The leakage coefficient for the overlying confining unit is also estimated. This information is needed to refine conceptual understanding of the groundwater flow system beneath the A and M Areas. The refined conceptual model will more adequately describe the pattern of groundwater flow, and will contribute to updating the open-quotes Zone of Captureclose quotes model that has been used in the initial phases of designing a groundwater remediation system in the A and M Areas

  6. A Mathematical View of Water Table Fluctuations in a Shallow Aquifer in Brazil

    NARCIS (Netherlands)

    Neto, Dagmar C.; Chang, Hung K.; van Genuchten, Martinus Th

    Detailed monitoring of the groundwater table can provide important data about both short- and long-term aquifer processes, including information useful for estimating recharge and facilitating groundwater modeling and remediation efforts. In this paper, we presents results of 4years (2002 to 2005)

  7. Low-density solvent-based vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction combined with gas chromatography-mass spectrometry for the fast determination of phthalate esters in bottled water.

    Science.gov (United States)

    Zhang, Yufeng; Lee, Hian Kee

    2013-01-25

    For the first time, a novel low-density solvent-based vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction (LDS-VSLLME) was developed for the fast, simple and efficient determination of six phthalate esters (PEs) in bottled water samples followed by gas chromatography-mass spectrometry (GC-MS). In the extraction procedure, the aqueous sample solution was injected into a mixture of extraction solvent (toluene) and surfactant (cetyltrimethyl ammonium bromide), which were placed in a glass tube with conical bottom, to form an emulsion by the assistance of vortex agitation. After extraction and phase separation by centrifugation, and removal of the spent sample, the toluene extract was collected and analyzed by GC-MS. The addition of surfactant enhanced the dispersion of extraction solvent in aqueous sample and was also favorable for the mass transfer of the analytes from the aqueous sample to the extraction solvent. Moreover, using a relatively less toxic surfactant as the emulsifier agent overcame the disadvantages of traditional organic dispersive solvents that are usually highly toxic and expensive and might conceivably decrease extraction efficiency to some extent since they are not as effective as surfactants themselves in generating an emulsion. With the aid of surfactant and vortex agitation to achieve good organic extraction solvent dispersion, extraction equilibrium was achieved within 1 min, indicating it was a fast sample preparation technique. Another prominent feature of the method was the simple procedure to collect a less dense than water solvent by a microsyringe. After extraction and phase separation, the aqueous sample was removed using a 5-mL syringe, thus leaving behind the extract, which was retrieved easily. This novel method simplifies the use of low-density solvents in DLLME. Under the optimized conditions, the proposed method provided good linearity in the range of 0.05-25 μg/L, low limits of detection (8-25 ng

  8. Electrodialytic soil remediation

    DEFF Research Database (Denmark)

    Karlsmose, Bodil; Ottosen, Lisbeth M.; Hansen, Lene

    1999-01-01

    The paper gives an overview of how heavy metals can be found in the soil and the theory of electrodialytic remediation. Basically electrodialytic remediation works by passing electric current through the soil, and the heavy metals in ionic form will carry some of the current. Ion-exchange membranes...... prevents the protons and the hydroxides ions from the electrode processes to enter the soil. The heavy metals are collected in a concentration compartment, which is separated from the soil by ion-exchange membranes. Examples from remediation experiments are shown, and it is demonstrated that it is possible...... to remediate soil polluted with heavy metals be this method. When adding desorbing agents or complexing agents, chosing the right current density, electrolyte and membranes, the proces can be optimised for a given remediation situation. Also electroosmosis is influencing the system, and if extra water...

  9. Organic contamination and remediation in the agricultural soils of China: A critical review.

    Science.gov (United States)

    Sun, Jianteng; Pan, Lili; Tsang, Daniel C W; Zhan, Yu; Zhu, Lizhong; Li, Xiangdong

    2018-02-15

    Soil pollution is a global problem in both developed and developing countries. Countries with rapidly developing economies such as China are faced with significant soil pollution problems due to accelerated industrialization and urbanization over the last decades. This paper provides an overview of published scientific data on soil pollution across China with particular focus on organic contamination in agricultural soils. Based on the related peer-reviewed papers published since 2000 (n=203), we evaluated the priority organic contaminants across China, revealed their spatial and temporal distributions at the national scale, identified their possible sources and fates in soil, assessed their potential environmental risks, and presented the challenges in current remediation technologies regarding the combined organic pollution of agricultural soils. The primary pollutants in Northeast China were polycyclic aromatic hydrocarbons (PAHs) due to intensive fossil fuel combustion. The concentrations of organochlorine pesticides (OCPs) and phthalic acid esters (PAEs) were higher in North and Central China owing to concentrated agricultural activities. The levels of polychlorinated biphenyls (PCBs) were higher in East and South China primarily because of past industrial operations and improper electronic waste processing. The co-existence of organic contaminants was severe in the Yangtze River Delta, Pearl River Delta, and Beijing-Tianjin-Hebei Region, which are the most populated and industrialized regions in China. Integrated biological-chemical remediation technologies, such as surfactant-enhanced bioremediation, have potential uses in the remediation of soil contaminated by multiple contaminants. This critical review highlighted several future research directions including combined pollution, interfacial interactions, food safety, bioavailability, ecological effects, and integrated remediation methods for combined organic pollution in soil. Copyright © 2017 Elsevier B

  10. Multi-phase flow modeling of soil contamination and soil remediation

    NARCIS (Netherlands)

    Dijke, van M.I.J.

    1997-01-01


    In this thesis multi-phase flow models are used to study the flow behavior of liquid contaminants in aquifers and of gases that are injected below the groundwater table for remediation purposes. Considered problems are redistribution of a lens of light nonaqueous phase

  11. Integrating borehole logs and aquifer tests in aquifer characterization

    Science.gov (United States)

    Paillet, Frederick L.; Reese, R.S.

    2000-01-01

    Integration of lithologic logs, geophysical logs, and hydraulic tests is critical in characterizing heterogeneous aquifers. Typically only a limited number of aquifer tests can be performed, and these need to be designed to provide hydraulic properties for the principle aquifers in the system. This study describes the integration of logs and aquifer tests in the development of a hydrostratigraphic model for the surficial aquifer system in and around Big Cypress National Preserve in eastern Collier County, Florida. Borehole flowmeter tests provide qualitative permeability profiles in most of 26 boreholes drilled in the Study area. Flow logs indicate the depth of transmissive units, which are correlated across the study area. Comparison to published studies in adjacent areas indicates that the main limestone aquifer of the 000000Tamiami Formation in the study area corresponds with the gray limestone aquifer in western Dade County and the water table and lower Tamiami Aquifer in western Collier County. Four strategically located, multiwell aquifer tests are used to quantify the qualitative permeability profiles provided by the flowmeter log analysis. The hydrostratigraphic model based on these results defines the main aquifer in the central part of the study area as unconfined to semiconfined with a transmissivity as high as 30,000 m2/day. The aquifer decreases in transmissivity to less than 10,000 m2/day in some parts of western Collier County, and becomes confined to the east and northeast of the study area, where transmissivity decreases to below 5000 m2/day.Integration of lithologic logs, geophysical logs, and hydraulic tests is critical in characterizing heterogeneous aquifers. Typically only a limited number of aquifer tests can be performed, and these need to be designed to provide hydraulic properties for the principle aquifers in the system. This study describes the integration of logs and aquifer tests in the development of a hydrostratigraphic model for the

  12. Impact of Sediment-Bound Iron on Redox Buffering in a Landfill Leachate Polluted Aquifer (Vejen, Denmark)

    DEFF Research Database (Denmark)

    Heron, Gorm; Christensen, Thomas Højlund

    1995-01-01

    in the reduced zones close to the landfill, and the aquifer oxidation capacity (OXC) related to iron oxides was depleted. Less than 2% of the total Fe(ll) was recovered as dissolved Fe(ll), whereas 1-20% was ion-exchangeable on the sediments. The majority of the Fe(ll) was in the solid state either as pyrite......(ll). This study presents evidence of substantial iron reduction buffering the reducing power of landfill leachate entering a shallow aquifer. It is also proposed that reduced sedimentbound iron species form in the plume, thereby increasing the need for oxygen if the aquifer was to be remediated....

  13. Remediating Contaminant Plumes in Groundwater with Shallow Excavations Containing Coarse Reactive Media.

    Science.gov (United States)

    Hudak, Paul F

    2018-02-01

    A groundwater flow and mass transport model tested the capability of shallow excavations filled with coarse, reactive media to remediate a hypothetical unconfined aquifer with a maximum saturated thickness of 5 m. Modeled as contaminant sinks, the rectangular excavations were 10 m downgradient of an initial contaminant plume originating from a source at the top of the aquifer. The initial plume was approximately 259 m long, 23 m wide, and 5 m thick, with a downgradient tip located approximately 100 m upgradient of the site boundary. The smallest trench capable of preventing offsite migration was 11 m long (measured perpendicular to groundwater flow), 4 m wide (measured parallel to groundwater flow), and 3 m deep. Results of this study suggest that shallow trenches filled with coarse filter media that partially penetrate unconfined aquifers may be a viable alternative for remediating contaminated groundwater at some sites.

  14. Remediating Contaminant Plumes in Groundwater with Shallow Excavations Containing Coarse Reactive Media

    Science.gov (United States)

    Hudak, Paul F.

    2018-02-01

    A groundwater flow and mass transport model tested the capability of shallow excavations filled with coarse, reactive media to remediate a hypothetical unconfined aquifer with a maximum saturated thickness of 5 m. Modeled as contaminant sinks, the rectangular excavations were 10 m downgradient of an initial contaminant plume originating from a source at the top of the aquifer. The initial plume was approximately 259 m long, 23 m wide, and 5 m thick, with a downgradient tip located approximately 100 m upgradient of the site boundary. The smallest trench capable of preventing offsite migration was 11 m long (measured perpendicular to groundwater flow), 4 m wide (measured parallel to groundwater flow), and 3 m deep. Results of this study suggest that shallow trenches filled with coarse filter media that partially penetrate unconfined aquifers may be a viable alternative for remediating contaminated groundwater at some sites.

  15. EPA Region 1 Sole Source Aquifers

    Data.gov (United States)

    U.S. Environmental Protection Agency — This coverage contains boundaries of EPA-approved sole source aquifers. Sole source aquifers are defined as an aquifer designated as the sole or principal source of...

  16. Degradation of petroleum hydrocarbons in a laboratory aquifer column

    International Nuclear Information System (INIS)

    Billowits, M.; Whyte, L.; Greer, C.; Ramsay, J.

    1998-01-01

    One of the primary mechanisms for eliminating hydrocarbon pollutants from the environment is degradation of hydrocarbons by indigenous microorganisms. This report describes a study in which samples from a petroleum polluted shallow aquifer in the Yukon were used which contained a hundred times greater concentration of psychrotropic bacteria than mesophilic bacteria. Results showed a maximum degradation of 47 per cent of the total petroleum hydrocarbon in columns which simulated the aquifer conditions and to which nutrients were added. It was concluded that although in this case bioaugmentation of the columns with a psychrotropic hydrocarbon-degrading consortium increased microbial numbers, total petroleum hydrocarbon degradation was not much greater than could be achieved by remediation with nutrients alone

  17. In situ Remediation Technologies

    NARCIS (Netherlands)

    Grotenhuis, J.T.C.; Rijnaarts, H.H.M.

    2011-01-01

    A summary of two decades of developments of In Situ remediation is presented in this chapter. The basic principles of In Situ technology application are addressed, such as equilibrium relations between contaminant phases, factors controlling biological and geochemical processes, contaminant

  18. Demonstration of risk-based decision analysis in remedial alternative selection and design

    International Nuclear Information System (INIS)

    Evans, E.K.; Duffield, G.M.; Massmann, J.W.; Freeze, R.A.; Stephenson, D.E.

    1993-01-01

    This study demonstrates the use of risk-based decision analysis (Massmann and Freeze 1987a, 1987b) in the selection and design of an engineering alternative for groundwater remediation at a waste site at the Savannah River Site, a US Department of Energy facility in South Carolina. The investigation focuses on the remediation and closure of the H-Area Seepage Basins, an inactive disposal site that formerly received effluent water from a nearby production facility. A previous study by Duffield et al. (1992), which used risk-based decision analysis to screen a number of ground-water remediation alternatives under consideration for this site, indicated that the most attractive remedial option is ground-water extraction by wells coupled with surface water discharge of treated effluent. The aim of the present study is to demonstrate the iterative use of risk-based decision analysis throughout the design of a particular remedial alternative. In this study, we consider the interaction between two episodes of aquifer testing over a 6-year period and the refinement of a remedial extraction well system design. Using a three-dimensional ground-water flow model, this study employs (1) geostatistics and Monte Carlo techniques to simulate hydraulic conductivity as a stochastic process and (2) Bayesian updating and conditional simulation to investigate multiple phases of aquifer testing. In our evaluation of a remedial alternative, we compute probabilistic costs associated with the failure of an alternative to completely capture a simulated contaminant plume. The results of this study demonstrate the utility of risk-based decision analysis as a tool for improving the design of a remedial alternative through the course of phased data collection at a remedial site

  19. Electrodialytic Soil Remediation

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Lene; Hansen, Henrik K.

    1997-01-01

    It is not possible for all heavy metal polluted soils to remediate it by an applied electric field alone. A desorbing agent must in different cases be added to the soil in order to make the process possible or to make it cost effective......It is not possible for all heavy metal polluted soils to remediate it by an applied electric field alone. A desorbing agent must in different cases be added to the soil in order to make the process possible or to make it cost effective...

  20. 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.

  1. Surfactant-enhanced cellulose nanocrystal Pickering emulsions.

    Science.gov (United States)

    Hu, Zhen; Ballinger, Sarah; Pelton, Robert; Cranston, Emily D

    2015-02-01

    The effect of surfactants on the properties of Pickering emulsions stabilized by cellulose nanocrystals (CNCs) was investigated. Electrophoretic mobility, interfacial tension, confocal microscopy and three-phase contact angle measurements were used to elucidate the interactions between anionic CNCs and cationic alkyl ammonium surfactants didecyldimethylammonium bromide (DMAB) and cetyltrimethylammonium bromide (CTAB). Both surfactants were found to adsorb onto CNCs with concentration-dependent morphology. At low concentrations, individual surfactant molecules adsorbed with alkyl tails pointing outward leading to hydrophobic CNCs. At higher concentrations, above the surfactant's apparent critical micelle concentration, surfactant aggregate morphologies on CNCs were inferred and the hydrophobicity of CNCs decreased. DMAB, which has two alkyl tails, rendered the CNCs more hydrophobic than CTAB which has only a single alkyl tail, at all surfactant concentrations. The change in CNC wettability from surfactant adsorption was directly linked to emulsion properties; adding surfactant increased the emulsion stability, decreased the droplet size, and controlled the internal phase of CNC Pickering emulsions. More specifically, a double transitional phase inversion, from oil-in-water to water-in-oil and back to oil-in-water, was observed for emulsions with CNCs and increasing amounts of DMAB (the more hydrophobic surfactant). With CNCs and CTAB, no phase inversion was induced. This work represents the first report of CNC Pickering emulsions with surfactants as well as the first CNC Pickering emulsions that can be phase inverted. The ability to surface modify CNCs in situ and tailor emulsions by adding surfactants may extend the potential of CNCs to new liquid formulations and extruded/spray-dried materials. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Remediation for contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Kivekaes, L. [Lohja Envirotec, Helsinki (Finland)

    2000-07-01

    A versatile remediation centre for contaminated soils has operated at Virkkala close to Helsinki since 1998. It is the first regional soil remediation centre in Finland and serves a large area in south- western Finland. Contaminated soils are collected from tens of small and large sites each year and transported to Virkkala for a very high class and environmentally safe treatment under controlled conditions. The centre consists of a 2 ha large hall for storage and treatment of the soils, a 1 ha outside bio-remediation field and a service and truck washing hall. Three treatment technologies are available at the centre: Stabilization/solidification, washing and bio-remediation. With these methods all the most common types of contamination can be treated: Heavy metals, oils, PAHs, creosotes and chlorophenols. Special care has been taken with prevention of environmental emissions, because the centre is located close to a housing area and on a lake-front. All the storage and treatment areas are covered with a double or triple bottom liner system and all environmental emissions are being monitored constantly. EU's Life Environment -fund has supported the project. (orig.)

  3. Trade Remedies: A Primer

    National Research Council Canada - National Science Library

    Jones, Vivian C

    2006-01-01

    The United States and many of its trading partners use laws known as trade remedies to mitigate the adverse impact of various trade practices on domestic industries and workers. U.S. antidumping laws (19 U.S.C. 1673 et seq...

  4. Applicability of petroleum horizontal drilling technology to hazardous waste site characterization and remediation

    International Nuclear Information System (INIS)

    Goranson, C.

    1992-09-01

    Horizontal wells have the potential to become an important tool for use in characterization, remediation and monitoring operations at hazardous waste disposal, chemical manufacturing, refining and other sites where subsurface pollution may develop from operations or spills. Subsurface pollution of groundwater aquifers can occur at these sites by leakage of surface disposal ponds, surface storage tanks, underground storage tanks (UST), subsurface pipelines or leakage from surface operations. Characterization and remediation of aquifers at or near these sites requires drilling operations that are typically shallow, less than 500-feet in depth. Due to the shallow nature of polluted aquifers, waste site subsurface geologic formations frequently consist of unconsolidated materials. Fractured, jointed and/or layered high compressive strength formations or compacted caliche type formations can also be encountered. Some formations are unsaturated and have pore spaces that are only partially filled with water. Completely saturated underpressured aquifers may be encountered in areas where the static ground water levels are well below the ground surface. Each of these subsurface conditions can complicate the drilling and completion of wells needed for monitoring, characterization and remediation activities. This report describes some of the equipment that is available from petroleum drilling operations that has direct application to groundwater characterization and remediation activities. A brief discussion of petroleum directional and horizontal well drilling methodologies is given to allow the reader to gain an understanding of the equipment needed to drill and complete horizontal wells. Equipment used in river crossing drilling technology is also discussed. The final portion of this report is a description of the drilling equipment available and how it can be applied to groundwater characterization and remediation activities

  5. Some new hydraulic and tracer measurement techniques for heterogeneous aquifer formations

    International Nuclear Information System (INIS)

    Ptak, T.; Teutsch, G.

    1990-01-01

    Groundwater contamination assessment and remediation activities demand reliable techniques for the determination of the governing aquifer parameters and their spatial distribution. In order to define guidelines and recommendations, some existing underground investigation techniques were tested and new methods have been developed as a part of the research program at the Horkheimer Insel experimental field site. In this paper, some new developed field and laboratory techniques are introduced and the results compared for two example monitoring wells located in the northern part of the field site. It is shown that highly conductive and highly heterogeneous aquifers demand high resolution investigation techniques. For transport predictions, new methods are needed that are able to detect preferential flow paths. Results from multilevel tracer tests show that simple analytical interpretations are not valid for this type of aquifer. (Author) (8 refs., 12 figs., tab.)

  6. Techniques for Source Zone and Plume Characterization of Tetrachloroethene in Fractured Limestone Aquifers

    DEFF Research Database (Denmark)

    Fjordbøge, Annika Sidelmann; Mosthaf, Klaus; Janniche, Gry S.

    Characterization of chlorinated solvents in fractured limestone aquifers is essential for proper development of site specific conceptual models and subsequent risk assessment and remediation. High resolution characterization is challenged by the difficulties involved in collection of intact core...... fractured limestone aquifers. The two sites represent different scales (source and plume) and contaminant levels (DNAPL and dissolved). The scope of the investigations was to evaluate different techniques for characterization of the contaminant distribution in the limestone aquifers and to obtain...... of the FACT field measurements, which allows the conversion of discrete activated carbon concentrations to aqueous concentrations at given hydraulic parameters and FACT parameters. The passive groundwater sampling with snap samplers resulted in significantly different concentration levels and concentration...

  7. EPA Region 1 Sole Source Aquifers

    Science.gov (United States)

    This coverage contains boundaries of EPA-approved sole source aquifers. Sole source aquifers are defined as an aquifer designated as the sole or principal source of drinking water for a given aquifer service area; that is, an aquifer which is needed to supply 50% or more of the drinking water for the area and for which there are no reasonable alternative sources should the aquifer become contaminated.The aquifers were defined by a EPA hydrogeologist. Aquifer boundaries were then drafted by EPA onto 1:24000 USGS quadrangles. For the coastal sole source aquifers the shoreline as it appeared on the quadrangle was used as a boundary. Delineated boundaries were then digitized into ARC/INFO.

  8. Remediation of sites with coal tar contamination. A case study

    International Nuclear Information System (INIS)

    Zapf-Gilje, R.; Patrick, G.C.; Lindroos, P.

    2000-01-01

    The production and use of coal tar was tied to the industrial revolution and its dependence on coal for energy and as chemical feedstock for a large range of organic and inorganic products. Coal tar was produced, often as a byproduct, by coal gasification plants. The North American coal tar production in the mid 1950s was in the order of 25 billion litres. The production, handling, storage and use of coal tar and its derivatives generated a legacy of soil and groundwater contamination that today requires remediation at high costs. At one such site, coal tar was manufactured into a variety of roofing and tarbased products, as well as the production of creosote, oil stains, solvents and anhydrous ammonia. Over its 60 years of operation, a number of chemicals were leaked, dumped or released to the soil and groundwater on the site, of which the most significant was a brown dense non-aqueous phase liquid (DNAPL) with an oil-like viscosity. This DNAPL migrated from the fill, through a pre-development floodplain silt layer and into an underlying sand aquifer. Portions of the DNAPL moved along preferential pathways associated with the coarser material in the aquifer and reached the nearby river sediments, resulting in elevated concentrations of polyaromatic hydrocarbons (PAH). Site remediation was conducted mitigate risks posed by the coal tar. Remediation has included: in-place management of deep soil contamination, removal of shallow soil with high PAH concentrations (i.e., 10 times the provincial concentration standards for commercial land use), control of dissolved contamination in groundwater, and recovery of free- phase creosote. The remediation also provided long-term protection of the adjacent aquatic habitat through a combination of groundwater and DNAPL control and recovery, removal of near-shore contaminated sediments, and containment and natural attenuation of far-shore contaminated sediments through the use of a layer of crushed rock placed as a protective cap

  9. Benzene dynamics and biodegradation in alluvial aquifers affected by river fluctuations.

    Science.gov (United States)

    Batlle-Aguilar, J; Morasch, B; Hunkeler, D; Brouyère, S

    2014-01-01

    The spatial distribution and temporal dynamics of a benzene plume in an alluvial aquifer strongly affected by river fluctuations was studied. Benzene concentrations, aquifer geochemistry datasets, past river morphology, and benzene degradation rates estimated in situ using stable carbon isotope enrichment were analyzed in concert with aquifer heterogeneity and river fluctuations. Geochemistry data demonstrated that benzene biodegradation was on-going under sulfate reducing conditions. Long-term monitoring of hydraulic heads and characterization of the alluvial aquifer formed the basis of a detailed modeled image of aquifer heterogeneity. Hydraulic conductivity was found to strongly correlate with benzene degradation, indicating that low hydraulic conductivity areas are capable of sustaining benzene anaerobic biodegradation provided the electron acceptor (SO4 (2-) ) does not become rate limiting. Modeling results demonstrated that the groundwater flux direction is reversed on annual basis when the river level rises up to 2 m, thereby forcing the infiltration of oxygenated surface water into the aquifer. The mobilization state of metal trace elements such as Zn, Cd, and As present in the aquifer predominantly depended on the strong potential gradient within the plume. However, infiltration of oxygenated water was found to trigger a change from strongly reducing to oxic conditions near the river, causing mobilization of previously immobile metal species and vice versa. MNA appears to be an appropriate remediation strategy in this type of dynamic environment provided that aquifer characterization and targeted monitoring of redox conditions are adequate and electron acceptors remain available until concentrations of toxic compounds reduce to acceptable levels. © 2013, National Ground Water Association.

  10. Modeling contaminant plumes in fractured limestone aquifers

    DEFF Research Database (Denmark)

    Mosthaf, Klaus; Brauns, Bentje; Fjordbøge, Annika Sidelmann

    Determining the fate and transport of contaminant plumes from contaminated sites in limestone aquifers is important because they are a major drinking water resource. This is challenging because they are often heavily fractured and contain chert layers and nodules, resulting in a complex transport...... model. The paper concludes with recommendations on how to identify and employ suitable models to advance the conceptual understanding and as decision support tools for risk assessment and the planning of remedial actions....... behavior. Improved conceptual models are needed for this type of site. Here conceptual models are developed by combining numerical models with field data. Several types of fracture flow and transport models are available for the modeling of contaminant transport in fractured media. These include...... the established approaches of the equivalent porous medium, discrete fracture and dual continuum models. However, these modeling concepts are not well tested for contaminant plume migration in limestone geologies. Our goal was to develop and evaluate approaches for modeling the transport of dissolved contaminant...

  11. A Review of the Multilevel Slug Test for Characterizing Aquifer Heterogeneity

    Directory of Open Access Journals (Sweden)

    Chia-Shyun Chen

    2012-01-01

    Full Text Available All aquifers are heterogeneous to a certain degree. The spatial distribution of hydraulic conductivity K(x, y, z, or aquifer heterogeneity, significantly influences the groundwater flow movement and associated solute transport. Of particular importance in designing an in-situ remediation plan is a knowledge of low-K layers because they are less accessible to remedial agents and form a bottleneck in remediation. The characterization of aquifer heterogeneity is essential to the solution of many practical and scientific groundwater problems. This article reviews the field technique using the multilevel slug test (MLST, which determines a series of K estimates at depths of interest in a well by making use of a double-packer system. The K(z obtained manifests the vertical variation of hydraulic conductivity in the vicinity of the test well, and the combination of K(z from different wells gives rise to a three-dimensional description of K(x, y, z. The MLST response is rather sensitive to hydraulic conductivity variation; e.g., it is oscillatory for highly permeable conditions (K > 5 × 10-4 m s-1 and a nonoscillatory for K < 5 × 10-4 m s-1. In this article we discuss the instrumentation of the double-packer system, the implementation of the depth-specific slug test, the data analysis methods for a spectrum of response characteristics usually observed in the field, and field applications of the MLST.

  12. Innovative mathematical modeling in environmental remediation

    International Nuclear Information System (INIS)

    Yeh, Gour T.; Gwo, Jin Ping; Siegel, Malcolm D.; Li, Ming-Hsu; Fang, Yilin; Zhang, Fan; Luo, Wensui; Yabusaki, Steven B.

    2013-01-01

    There are two different ways to model reactive transport: ad hoc and innovative reaction-based approaches. The former, such as the Kd simplification of adsorption, has been widely employed by practitioners, while the latter has been mainly used in scientific communities for elucidating mechanisms of biogeochemical transport processes. It is believed that innovative mechanistic-based models could serve as protocols for environmental remediation as well. This paper reviews the development of a mechanistically coupled fluid flow, thermal transport, hydrologic transport, and reactive biogeochemical model and example-applications to environmental remediation problems. Theoretical bases are sufficiently described. Four example problems previously carried out are used to demonstrate how numerical experimentation can be used to evaluate the feasibility of different remediation approaches. The first one involved the application of a 56-species uranium tailing problem to the Melton Branch Subwatershed at Oak Ridge National Laboratory (ORNL) using the parallel version of the model. Simulations were made to demonstrate the potential mobilization of uranium and other chelating agents in the proposed waste disposal site. The second problem simulated laboratory-scale system to investigate the role of natural attenuation in potential off-site migration of uranium from uranium mill tailings after restoration. It showed inadequacy of using a single Kd even for a homogeneous medium. The third example simulated laboratory experiments involving extremely high concentrations of uranium, technetium, aluminum, nitrate, and toxic metals (e.g.,Ni, Cr, Co). The fourth example modeled microbially-mediated immobilization of uranium in an unconfined aquifer using acetate amendment in a field-scale experiment. The purposes of these modeling studies were to simulate various mechanisms of mobilization and immobilization of radioactive wastes and to illustrate how to apply reactive transport models

  13. Innovative mathematical modeling in environmental remediation

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Gour T. [Taiwan Typhoon and Flood Research Institute (Taiwan); National Central Univ. (Taiwan); Univ. of Central Florida (United States); Gwo, Jin Ping [Nuclear Regulatory Commission (NRC), Rockville, MD (United States); Siegel, Malcolm D. [Sandia National Laboratories, Albuquerque, NM (United States); Li, Ming-Hsu [National Central Univ. (Taiwan); ; Fang, Yilin [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Zhang, Fan [Inst. of Tibetan Plateau Research, Chinese Academy of Sciences (China); Luo, Wensui [Inst. of Tibetan Plateau Research, Chinese Academy of Sciences (China); Yabusaki, Steven B. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)

    2013-05-01

    There are two different ways to model reactive transport: ad hoc and innovative reaction-based approaches. The former, such as the Kd simplification of adsorption, has been widely employed by practitioners, while the latter has been mainly used in scientific communities for elucidating mechanisms of biogeochemical transport processes. It is believed that innovative mechanistic-based models could serve as protocols for environmental remediation as well. This paper reviews the development of a mechanistically coupled fluid flow, thermal transport, hydrologic transport, and reactive biogeochemical model and example-applications to environmental remediation problems. Theoretical bases are sufficiently described. Four example problems previously carried out are used to demonstrate how numerical experimentation can be used to evaluate the feasibility of different remediation approaches. The first one involved the application of a 56-species uranium tailing problem to the Melton Branch Subwatershed at Oak Ridge National Laboratory (ORNL) using the parallel version of the model. Simulations were made to demonstrate the potential mobilization of uranium and other chelating agents in the proposed waste disposal site. The second problem simulated laboratory-scale system to investigate the role of natural attenuation in potential off-site migration of uranium from uranium mill tailings after restoration. It showed inadequacy of using a single Kd even for a homogeneous medium. The third example simulated laboratory experiments involving extremely high concentrations of uranium, technetium, aluminum, nitrate, and toxic metals (e.g.,Ni, Cr, Co).The fourth example modeled microbially-mediated immobilization of uranium in an unconfined aquifer using acetate amendment in a field-scale experiment. The purposes of these modeling studies were to simulate various mechanisms of mobilization and immobilization of radioactive wastes and to illustrate how to apply reactive transport models

  14. BP-5 Remedial Investigation Slug-Test Characterization Results for Well 699-52-55A

    Energy Technology Data Exchange (ETDEWEB)

    Newcomer, Darrell R.

    2008-07-21

    Pacific Northwest National Laboratory conducted slug-test characterization at the final, completed BP-5 Remedial Investigation well 699-52-55A near the 200-East Area at the Hanford Site on April 22, 2008. The slug-test characterization was in support of the BP-5 Remedial Investigation. The portion of the unconfined aquifer tested is composed of sediments of the lower Ringold Formation and the underlying Elephant Mountain basalt flowtop. The basalt flowtop unit was included as part of the effective test-interval length for the slug-test analysis because the flowtop unit is hydraulically communicative with the unconfined aquifer. Estimates of hydraulic conductivity for the effective test-interval length represent composite values for the lower Ringold Formation and the underlying Elephant Mountain basalt flow top.

  15. As contamination in Mercedes aquifer groundwater

    International Nuclear Information System (INIS)

    Goso, C; Manganelli, A; Fernandez, T; Garcia, M; Gimeno, D; Perez, C.

    2006-01-01

    This work is about the quality of the groundwater an the arsenic content in different aquifers in Uruguay. The first data obtained of arsenic concentrations are from subterranes water in the Mercedes aquifers

  16. The Citronelle aquifers in Mississippi

    Science.gov (United States)

    Boswell, E.H.

    1979-01-01

    The Citronelle aquifers consist of sand and gravel of Pliocene age that forms a discontinuous outcrop area of about 6,000 square miles in southern Mississippi. The beds dip to the south at an average rate of about 6 feet per mile. The unconfined aquifers are used mostly for domestic and farm use but also supply water to several municipalities and industries. The average saturated thickness of the aquifers is about 45 feet. This physically limits drawdown space and, although specific capacities are high, yields generally do not exceed a few hundred gallons per minute. Water levels have not declined significantly because withdrawals are small. Water quality is generally good although in some places there are objectionally high concentrations iron and in some the water is acidic.

  17. Aquifer parameter identification and interpretation with different ...

    African Journals Online (AJOL)

    because within the aquifer test area there may appear heterogeneities and anisotropics which hinder the application of a single model. ... Abstract for&: aquifer parameter, [ransmissivity, storage coefficient, aquifer tests, analytical methods. Movement and ... since Cooper and Jacob (1946) proposed their simple and widely.

  18. Aquifers Characterization and Productivity in Ellala Catchment ...

    African Journals Online (AJOL)

    This paper assesses the aquifer characteristics and productivity nature of different rocks and sediments using geological and hydrogeological methods in Ellala ... Hydrodynamic analyses of the aquifers reveal that in the limestone aquifer hydraulic conductivity is ranging from 0.046 to 4.65 m/day with a mean value of 1.44 ...

  19. Hydrocarbons spill remediation in the case Barreal-Belen, Costa Rica

    International Nuclear Information System (INIS)

    Vargas Fallas, Luis Carlos

    2009-01-01

    The advance in the attention of the hydrocarbon spill case occurred in Barreal-Belen, Costa Rica, is presented. The leakage consists about 30,000 liters of gasoline and diesel compounds, which are contained in an aquifer hanging located a depth of 20 to 22 meters. In this aquifer lies beneath it a layer of calcined tuff has worked as a seal and prevented the collimated flow to aquifers that underlie and are used to supply populations. The strategy to achieve the remediation work established is presented by the Interagency Committee in 2005. The measures adopted to separate hydrocarbons from waters have established a prognosis in years of operation, according to two cleanup scenarios, presented to two months of initiated. (author) [es

  20. DOE'S remedial action assurance program

    International Nuclear Information System (INIS)

    Welty, C.G. Jr.; Needels, T.S.; Denham, D.H.

    1984-10-01

    The formulation and initial implementation of DOE's Assurance Program for Remedial Action are described. It was initiated in FY 84 and is expected to be further implemented in FY 85 as the activities of DOE's Remedial Action programs continue to expand. Further APRA implementation will include additional document reviews, site inspections, and program office appraisals with emphasis on Uranium Mill Tailings Remedial Action Program and Surplus Facilities Management Program

  1. CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY

    Energy Technology Data Exchange (ETDEWEB)

    BERGMAN, T. B.; STEFANSKI, L. D.; SEELEY, P. N.; ZINSLI, L. C.; CUSACK, L. J.

    2012-09-19

    THE CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY WAS CONDUCTED TO DEVELOP AN OPTIMAL SEQUENCE OF REMEDIATION ACTIVITIES IMPLEMENTING THE CERCLA DECISION ON THE CENTRAL PLATEAU. THE STUDY DEFINES A SEQUENCE OF ACTIVITIES THAT RESULT IN AN EFFECTIVE USE OF RESOURCES FROM A STRATEGIC PERSPECTIVE WHEN CONSIDERING EQUIPMENT PROCUREMENT AND STAGING, WORKFORCE MOBILIZATION/DEMOBILIZATION, WORKFORCE LEVELING, WORKFORCE SKILL-MIX, AND OTHER REMEDIATION/DISPOSITION PROJECT EXECUTION PARAMETERS.

  2. The Remediation of Nosferatu

    DEFF Research Database (Denmark)

    Ghellal, Sabiha; Morrison, Ann; Hassenzahl, Marc

    2014-01-01

    In this paper we present The Remediation of Nosferatu, a location based augmented reality horror adventure. Using the theory of fictional universe elements, we work with diverse material from Nosferatu’s horror genre and vampire themes as a case study. In this interdisciplinary research we...... intertwine traditional storytelling and scriptwriting skills with interaction design methods. For the game setting, we create hybrid spaces merging the fictional universe and the physical environment into one pervasive experience, centering around a variety of augmented reality activities played out...

  3. Catalysts for Environmental Remediation

    DEFF Research Database (Denmark)

    Abrams, B. L.; Vesborg, Peter Christian Kjærgaard

    2013-01-01

    on titania (V2O5-WO3/TiO2) as the example catalyst. The main photocatalysts examined for mineralization of organic compounds were TiO2 and MoS2. It is important to obtain insight into the catalyst structure-to-activity relationship in order to understand and locate the active site(s). In this chapter......The properties of catalysts used in environmental remediation are described here through specific examples in heterogeneous catalysis and photocatalysis. In the area of heterogeneous catalysis, selective catalytic reduction (SCR) of NOx was used as an example reaction with vanadia and tungsta...

  4. Saxton soil remediation project

    International Nuclear Information System (INIS)

    Holmes, R.D.

    1995-01-01

    The Saxton Nuclear Experimental Facility (SNEF) consists of a 23-MW(thermal) pressurized light water thermal reactor located in south central Pennsylvania. The Saxton Nuclear Experimental Corporation (SNEC), a wholly owned subsidiary of the General Public Utilities (GPU) Corporation, is the licensee for the SNEF. Maintenance and decommissioning activities at the site are conducted by GPU Nuclear, also a GPU subsidiary and operator of the Three Mile Island and Oyster Creek nuclear facilities. The remediation and radioactive waste management of contaminated soils is described

  5. Field Test of Enhanced Remedial Amendment Delivery Using a Shear-Thinning Fluid

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J.; Vermeul, Vincent R.; Adamson, David; Oostrom, Martinus; Zhong, Lirong; Mackley, Rob D.; Fritz, Brad G.; Horner, Jacob A.; Johnson, Timothy C.; Thomle, Jonathan N.; Newcomer, Darrell R.; Johnson, Christian D.; Rysz, Michal; Wietsma, Thomas W.; Newell, Charles J.

    2015-03-01

    Heterogeneity of hydraulic properties in aquifers may lead to contaminants residing in lower-permeability zones where it is difficult to deliver remediation amendments using conventional injection processes. The focus of this effort is to examine use of a shear-thinning fluid (STF) to improve the uniformity of remedial amendment distribution within a heterogeneous aquifer. Previous studies have demonstrated the significant potential of STFs for improving remedial amendment delivery in heterogeneous aquifers, but quantitative evaluation of these improvements from field applications are lacking. A field-scale test was conducted that compares data from successive injection of a tracer in water followed by injection of a tracer in a STF to evaluate the impact of the STF on tracer distribution uniformity in the presence of permeability contrasts within the targeted injection zone. Data from tracer breakthrough at multiple depth-discrete monitoring intervals and electrical resistivity tomography showed that inclusion of STF in the injection solution slowed movement in high-permeability pathways, improved delivery of amendment to low-permeability materials, and resulted in better uniformity in injected fluid distribution within the targeted treatment zone.

  6. Remediating Remediation: From Basic Writing to Writing across the Curriculum

    Science.gov (United States)

    Faulkner, Melissa

    2013-01-01

    This article challenges faculty members and administrators to rethink current definitions of remediation. First year college students are increasingly placed into basic writing courses due to a perceived inability to use English grammar correctly, but it must be acknowledged that all students will encounter the need for remediation as they attempt…

  7. Arsenic levels in groundwater aquifer

    African Journals Online (AJOL)

    Miodrag Jelic

    5Faculty of Ecology and Environmental Sciences, Union-Nikola Tesla University, Belgrade, Serbia. 6Department of Chemistry, Faculty of Science, University of Kragujevac, Kragujevac, Serbia. Accepted 31 December, 2012. As part of a survey on the groundwater aquifer at the Neoplanta source site, standard laboratory.

  8. Lasagna trademark soil remediation

    International Nuclear Information System (INIS)

    1996-04-01

    Lasagna trademark is an integrated, in situ remediation technology being developed which remediates soils and soil pore water contaminated with soluble organic compounds. Lasagna trademark is especially suited to sites with low permeability soils where electroosmosis can move water faster and more uniformly than hydraulic methods, with very low power consumption. The process uses electrokinetics to move contaminants in soil pore water into treatment zones where the contaminants can be captured and decomposed. Initial focus is on trichloroethylene (TCE), a major contaminant at many DOE and industrial sites. Both vertical and horizontal configurations have been conceptualized, but fieldwork to date is more advanced for the vertical configuration. Major features of the technology are electrodes energized by direct current, which causes water and soluble contaminants to move into or through the treatment layers and also heats the soil; treatment zones containing reagents that decompose the soluble organic contaminants or adsorb contaminants for immobilization or subsequent removal and disposal; and a water management system that recycles the water that accumulates at the cathode (high pH) back to the anode (low pH) for acid-base neutralization. Alternatively, electrode polarity can be reversed periodically to reverse electroosmotic flow and neutralize pH

  9. Remedial action technology - arid

    International Nuclear Information System (INIS)

    Hakonson, T.E.; DePoorter, G.L.; Nyhan, J.W.; Perkins, B.A.; Lane, L.J.

    1982-01-01

    A summary is presented of the low-level waste remedial action program at Los Alamos. The experimental design and progress is described for the experiments on second generation intrusion barriers, subsidence effects on SLB components, moisture cycling effects on chemical transport, and erosion control methodologies. The soil moisture data from the bio-intrusion and moisture cycling experiments both demonstrate the overwhelming importance of vegetation in minimizing infiltration of water through trench covers and backfill. Evaporation, as a water loss component in trench covers, is only effective in reducing soil moisture within 40 cm of the trench cover surface. Moisture infiltrating past the zone of evaporation in unvegetated or poorly vegetated trench covers is in storage and accumulates until drainage out of the soil profile occurs. Judicious selection of vegetation species for revegetating a low-level waste site may prevent infiltration of moisture into the trench and, when coupled with other design features (i.e. trench cover slope, tilling and seeding practice), may greatly reduce problems with erosion. Standard US Department of Agriculture erosion plots, when coupled with a state-of-the-art water balance and erosion model (CREAMS) promises to be highly useful in screening proposed remedial action cover designs for low-level waste sites. The erosion plot configuration allows for complete accounting of the water balance in a soil profile. This feature enables the user to optimize cover designs to minimize erosion and infiltration of water into the trench

  10. Aquifer thermal energy stores in Germany

    International Nuclear Information System (INIS)

    Kabus, F.; Seibt, P.; Poppei, J.

    2000-01-01

    This paper describes the state of essential demonstration projects of heat and cold storage in aquifers in Germany. Into the energy supply system of the buildings of the German Parliament in Berlin, there are integrated both a deep brine-bearing aquifer for the seasonal storage of waste heat from power and heat cogeneration and a shallow-freshwater bearing aquifer for cold storage. In Neubrandenburg, a geothermal heating plant which uses a 1.200 m deep aquifer is being retrofitted into an aquifer heat storage system which can be charged with the waste heat from a gas and steam cogeneration plant. The first centralised solar heating plant including an aquifer thermal energy store in Germany was constructed in Rostock. Solar collectors with a total area of 1000m 2 serve for the heating of a complex of buildings with 108 flats. A shallow freshwater-bearing aquifer is used for thermal energy storage. (Authors)

  11. Herbal remedies and supplements for weight loss

    Science.gov (United States)

    Weight loss - herbal remedies and supplements; Obesity - herbal remedies; Overweight - herbal remedies ... health care provider. Nearly all over-the-counter supplements with claims of weight-loss properties contain some ...

  12. Electrodialytic remediation of solid waste

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Ottosen, Lisbeth M.; Karlsmose, Bodil

    1996-01-01

    Electrodialytic remediation of heavy metal polluted solid waste is a method that combines the technique of electrodialysis with the electromigration of ions in the solid waste. Results of laboratory scale remediation experiments of soil are presented and considerations are given on how to secure...

  13. Shallow Aquifer Methane Gas Source Assessment

    Science.gov (United States)

    Coffin, R. B.; Murgulet, D.; Rose, P. S.; Hay, R.

    2014-12-01

    Shale gas can contribute significantly to the world's energy demand. Hydraulic fracturing (fracking) on horizontal drill lines developed over the last 15 years makes formerly inaccessible hydrocarbons economically available. From 2000 to 2035 shale gas is predicted to rise from 1% to 46% of the total natural gas for the US. A vast energy resource is available in the United States. While there is a strong financial advantage to the application of fracking there is emerging concern about environmental impacts to groundwater and air quality from improper shale fracking operations. Elevated methane (CH4) concentrations have been observed in drinking water throughout the United States where there is active horizontal drilling. Horizontal drilling and hydraulic-fracturing can increase CH4 transport to aquifers, soil and the vadose zone. Seepage can also result from casing failure in older wells. However, there is strong evidence that elevated CH4 concentrations can be associated with topographic and hydrogeologic features, rather than shale-gas extraction processes. Carbon isotope geochemistry can be applied to study CH4source(s) in shallow vadose zone and groundwater systems. A preliminary TAMU-CC isotope data set from samples taken at different locations in southern Texas shows a wide range of CH4 signatures suggesting multiple sources of methane and carbon dioxide. These data are interpreted to distinguish regions with methane contributions from deep-sourced horizontal drilling versus shallow system microbial production. Development of a thorough environmental assessment using light isotope analysis can provide understanding of shallow anthropogenic versus natural CH4sources and assist in identifying regions that require remedial actions.

  14. Enhanced Remedial Amendment Delivery to Subsurface Using Shear Thinning Fluid and Aqueous Foam

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Lirong; Szecsody, James E.; Oostrom, Martinus; Truex, Michael J.; Shen, Xin; Li, Xiqing

    2011-04-23

    A major issue with in situ subsurface remediation is the ability to achieve an even spatial distribution of remedial amendments to the contamination zones in an aquifer or vadose zone. Delivery of amendment to the aquifer using shear thinning fluid and to the vadose zone using aqueous foam has the potential to enhance the amendment distribution into desired locations and improve the remediation. 2-D saturated flow cell experiments were conducted to evaluate the enhanced sweeping, contaminant removal, and amendment persistence achieved by shear thinning fluid delivery. Bio-polymer xanthan gum solution was used as the shear thinning fluid. Unsaturated 1-D column and 2-D flow cell experiments were conducted to evaluate the mitigation of contaminant mobilization, amendment uniform distribution enhancement, and lateral delivery improvement by foam delivery. Surfactant sodium lauryl ether sulfate was used as the foaming agent. It was demonstrated that the shear thinning fluid injection enhanced the fluid sweeping over a heterogeneous system and increased the delivery of remedial amendment into low-permeability zones. The persistence of the amendment distributed into the low-perm zones by the shear thinning fluid was prolonged compared to that of amendment distributed by water injection. Foam delivery of amendment was shown to mitigate the mobilization of highly mobile contaminant from sediments under vadose zone conditions. Foam delivery also achieved more uniform amendment distribution in a heterogeneous unsaturated system, and demonstrated remarkable increasing in lateral distribution of the injected liquid compared to direct liquid injection.

  15. Cognitive Remediation in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Joana Vieira

    2014-06-01

    Full Text Available Several reviews of the literature support the idea that cognitive deficits observed in a large percentage of patients with schizophrenia are responsible for the cognitive performance deficit and functional disability associated with the disease. The grow- ing importance of neurocognition in Psychiatry, especially with regard to planning strategies and rehabilitative therapies to improve the prognosis of patients contrib- utes to the interest of achieving this literature review on cognitive rehabilitation in schizophrenia. In this work, drawn from research in the areas of schizophrenia, cog- nition, cognitive rehabilitation and cognitive remediation (2000-2012 through PubMed and The Cochrane Collaboration, it is intended, to describe the types of psychological and behavioral therapies recommended in the treatment of cognitive disabilities in patients diagnosed with schizophrenia. This review will also highlight the clinical and scientific evidence of each of these therapies, as their effect on cognitive performance, symptoms and functionality in patients with schizophrenia.

  16. Kinetics and Efficiency of H2O2 Activation by Iron-Containing Minerals and Aquifer Materials

    Science.gov (United States)

    Pham, Anh Le-Tuan; Doyle, Fiona M.; Sedlak, David L.

    2014-01-01

    To gain insight into factors that control H2O2 persistence and ˙OH yield in H2O2-based in situ chemical oxidation systems, the decomposition of H2O2 and transformation of phenol were investigated in the presence of iron-containing minerals and aquifer materials. Under conditions expected during remediation of soil and groundwater, the stoichiometric efficiency, defined as the amount of phenol transformed per mole of H2O2 decomposed, varied from 0.005 to 0.28%. Among the iron-containing minerals, iron oxides were 2 to 10 times less efficient in transforming phenol than iron-containing clays and synthetic iron-containing catalysts. In both iron-containing mineral and aquifer materials systems, the stoichiometric efficiency was inversely correlated with the rate of H2O2 decomposition. In aquifer materials systems, the stoichiometric efficiency was also inversely correlated with the Mn content, consistent with the fact that the decomposition of H2O2 on manganese oxides does not produce ˙OH. Removal of iron and manganese oxide coatings from the surface of aquifer materials by extraction with citrate-bicarbonate-dithionite slowed the rate of H2O2 decomposition on aquifer materials and increased the stoichiometric efficiency. In addition, the presence of 2 mM of dissolved SiO2 slowed the rate of H2O2 decomposition on aquifer materials by over 80% without affecting the stoichiometric efficiency. PMID:23047055

  17. Visualization of residual organic liquid trapped in aquifers

    International Nuclear Information System (INIS)

    Conrad, S.H.; Wilson, J.L.; Mason, W.R.; Peplinski, W.J.

    1992-01-01

    Organic liquids that are essentially immiscible with water migrate through the subsurface under the influence of capillary, viscous, and buoyancy forces. These liquids originate from the improper disposal of hazardous wastes, and the spills and leaks of petroleum hydrocarbons and solvents. The flow visualization experiments described in this study examined the migration of organic liquids through the saturated zone of aquifers, with a primary focus on the behavior of the residual organic liquid saturation, referring to that portion of the organic liquid that is trapped by capillary forces. Etched glass micromodels were used to visually observe dynamic multiphase displacement processes in pore networks. The resulting fluid distributions were photographed. Pore and blob casts were produced by a technique in which an organic liquid was solidified in place within a sand column at the conclusion of a displacement. The columns were sectioned and examined under optical and scanning electron microscopes. Photomicrographs of these sections show the morphology of the organic phase and its location within the sand matrix. The photographs from both experimental techniques reveal that in the saturated zone large amounts of residual organic liquid are trapped as isolated blobs of microscopic size. The size, shape, and spatial distribution of these blobs of residual organic liquid affect the dissolution of organic liquid into the water phase and the biotransformation of organic components. These processes are of concern for the prediction of pollution migration and the design of aquifer remediation schemes

  18. Interconnectivity between the Superficial Aquifer and the Deep Confined Aquifers of the Gnangara Mound, Western Australia

    International Nuclear Information System (INIS)

    Salama, Ramsis B.

    2005-01-01

    Perth groundwater resources are obtained from three major aquifers that occur beneath the Perth metropolitan area: the Superficial aquifer, Leederville aquifer and Yarragadee aquifer. Each aquifer has a unique seasonal water level pattern controlled by soils, geomorphology and geology. Land use is mainly responsible for variations in recharge; however, the hydraulic properties control aquifer response and water level pattern to a greater degree. Groundwater in the three aquifers is generally of very good quality except in localised areas. Salinity increases with depth and in direction of groundwater flow in the three aquifers. The best water quality is in the Superficial aquifer in the Wanneroo well field area. The geochemistry and stable isotope signatures from the three major aquifers revealed distinct water types that suggest very little hydraulic connection or mixing of waters between these aquifers at the present abstraction and recharge regimes. The results also show that the Leederville and Yarragadee aquifers were recharged during earlier cooler times while the Superficial aquifer is being recharged at present

  19. Field Investigation of Natural Attenuation of a Petroleum Hydrocarbon Contaminated Aquifer, Gyeonggi Province, Korea

    Science.gov (United States)

    Yang, J.; Lee, K.; Bae, G.

    2004-12-01

    In remediation of a petroleum hydrocarbon contaminated aquifer, natural attenuation may be significant as a remedial alternative. Therefore, natural attenuation should be investigated in the field in order to effectively design and evaluate the remediation strategy at the contaminated site. This study focused on evaluating the natural attenuation for benzene, toluene, ethylbenzene, and xylene (BTEX) at a contaminated site in South Korea. At the study site, the aquifer is composed of a high permeable gravel layer and relatively low permeable sandy-silt layers. Groundwater level vertically fluctuated between 1m and 2m throughout the year (April, 2003~June, 2004) and showed direct response to rainfall events. Chemical analyses of sampled groundwater were performed to investigate the concentrations of various chemical species which are associated with the natural attenuation processes. To evaluate the degree of the biodegradation, the expressed biodegradation capacity (EBC) analysis was done using aerobic respiration, nitrate reduction, manganese reduction, ferric iron reduction, and sulfate reduction as an indicator. High EBC value of sulfate indicate that anaerobic biodegradation by sulfate reduction was a dominant process of mineralization of BTEX at this site. The EBC values decrease sensitively when heavy rainfall occurs due to the dilution and inflow of electron acceptors through a gravel layer. The first-order biodegradation rates of BTEX were estimated by means of the Buscheck and Alcantar method (1995). Results show that the natural attenuation rate of benzene was the highest among the BTEX.

  20. French uranium mining sites remediation

    International Nuclear Information System (INIS)

    Roche, M.

    2002-01-01

    Following a presentation of the COGEMA's general policy for the remediation of uranium mining sites and the regulatory requirements, the current phases of site remediation operations are described. Specific operations for underground mines, open pits, milling facilities and confining the milled residues to meet long term public health concerns are detailed and discussed in relation to the communication strategies to show and explain the actions of COGEMA. A brief review of the current remediation situation at the various French facilities is finally presented. (author)

  1. Chaos and remedial investigations

    International Nuclear Information System (INIS)

    Galbraith, R.M.

    1991-01-01

    Current research into the nature of chaos indicates that even for systems that are well known and easily modeled, slight changes in the scale used to measure the input have unpredictable results in the model output. The conduct of a remedial investigation (RI) is dictated by well-established rules of investigation and management, yet small changes in project orientation, regulatory environment, or site conditions have unpredictable consequences to the project. The consequences can lead to either brilliant success or utter failure. The chaotic effect of a change in scale is most often illustrated by an exercise in measuring the length of the coast of Great Britain. If a straight ruler 10-kilometers long is used, the sum of the 10-kilometer increments gives the length of the coast. If the ruler is changed to five kilometers long and the exercise is repeated, the sum of the five-kilometer increments will not be the same as the sum of the 10-kilometer increments. Nor is there a way to predict what the length of the coast will be using any other scale. Several examples from the Fernald Project RI are used to illustrate open-quotes changes in scaleclose quotes in both technical and management situations. Given that there is no way to predict the outcome of scale changes in a RI, technical and project management must be alert to the fact that a scale has changed and the investigation is no longer on the path it was thought to be on. The key to success, therefore, is to develop specific units of measure for a number of activities, in addition to cost and schedule, and track them regularly. An example for tracking a portion of the field investigation is presented. The determination of effective units of measure is perhaps the most difficult aspect of any project. Changes in scale sometimes go unnoticed until suddenly the budget is expended and only a portion of the work is completed. Remedial investigations on large facilities provide new and complex challenges

  2. Laboratory Development of Polyphosphate Remediation Technology for In Situ Treatment of Uranium Contamination in the Vadose Zone and Capillary Fringe

    International Nuclear Information System (INIS)

    Wellman, Dawn M.; Pierce, Eric M.; Bovaird, Chase C.; Griswold, Kimberly M.; Gunderson, Katie M.; Webb, Samuel M.; Bargar, John R.

    2009-01-01

    A laboratory testing program has been conducted to optimize polyphosphate remediation technology for implementation through a field-scale technology infiltration demonstration to stabilize soluble, uranium-bearing source phases in the vadose zone and capillary fringe. Source treatment in the deep vadose zone will accelerate the natural attenuation of uranium to more thermodynamically stable uranium-phosphate minerals, enhancing the performance of the proposed polyphosphate remediation within the 300 Area aquifer. The objective of this investigation was to develop polyphosphate remediation technology to treat uranium contamination contained within the deep vadose zone and capillary fringe. This chapter presents the results of an investigation that evaluated the rate and extent of reaction between polyphosphate and the uranium mineral phases present within the 300 Area, and autunite formation as a function of polyphosphate formulation and concentration. This information is critical for identifying the optimum implementation approach and controlling the flux of uranium to the underlying aquifer during remediation. Results from this investigation may be used to design a full-scale remediation of uranium at the 300 Area of the Hanford Site.

  3. Opium the Best Remedy

    Directory of Open Access Journals (Sweden)

    Harold Merskey

    2004-01-01

    Full Text Available Sydenham was the leading English physician of the 17th century and probably to the present time. He was using a well tried remedy. It had been known by then for about 4000 years, frequently mentioned by Hippocrates, and recognized in use in medieval Europe where it probably came through Arabic traders and was well established in use in Paris by the 12th century (2. Professional concerns up to the time of Sydenham were not about addiction. As can be seen from his text, they were about whether the drug was available in adequate preparations, whether there was any difference between opium and other narcotics, particularly comparing the natural juice with "its artificial preparations" (1 (all of which he thought to be about equal in effect, whether it was stimulant or restorative and invigorating, and whether it was being properly used for all the conditions in which it could be helpful. Addiction, dependence and insanity are not mentioned, although the fact that it could occasionally promote excitement ("frenzy" was known.

  4. A responsible remediation strategy

    International Nuclear Information System (INIS)

    Knowles, C.R.

    1992-01-01

    This paper deals with an approach to cleaning up the residue of 150 years of intense urban and industrial development in the United States. The discussion focuses on several choices and strategies that business can adopt given the existing environmental laws and the socio-economic trends of the 1990's. The thesis of this paper is that the best business strategy for dealing with environmental liabilities is to act affirmatively and aggressively. An aggressive, pro-active approach to environmental remediation liabilities makes good business sense. It allows a company to learn the true size of the problem early. Early assessment and prioritization allows one to control the course and conduct of the cleanup. Early voluntary action is always viewed favorably by agencies. It gives one control over spending patterns which has value in and of itself. Voluntary cleanups are certainly faster and invariably more efficient. And they attain clearly acceptable standards. The volunteering company that takes the lead in a multi-party site finds that the courts are supportive in helping the volunteer collect from recalcitrant polluters. All of these pluses have a direct and positive impact on the bottom line and that means that the aggressive approach is the right thing to do for both stockholders and the communities where a business exists

  5. ICDF Complex Remedial Action Report

    Energy Technology Data Exchange (ETDEWEB)

    W. M. Heileson

    2007-09-26

    This Idaho CERCLA Disposal Facility (ICDF) Remedial Action Report has been prepared in accordance with the requirements of Section 6.2 of the INEEL CERCLA Disposal Facility Remedial Action Work Plan. The agency prefinal inspection of the ICDF Staging, Storage, Sizing, and Treatment Facility (SSSTF) was completed in June of 2005. Accordingly, this report has been developed to describe the construction activities completed at the ICDF along with a description of any modifications to the design originally approved for the facility. In addition, this report provides a summary of the major documents prepared for the design and construction of the ICDF, a discussion of relevant requirements and remedial action objectives, the total costs associated with the development and operation of the facility to date, and identification of necessary changes to the Agency-approved INEEL CERCLA Disposal Facility Remedial Action Work Plan and the ICDF Complex Operations and Maintenance Plan.

  6. Honey: An Effective Cough Remedy?

    Science.gov (United States)

    ... cough remedy? Is it true that honey calms coughs better than cough medicine does? Answers from James M. Steckelberg, M. ... throat. But honey alone may be an effective cough suppressant, too. In one study, children age 2 ...

  7. Plant-based remediation processes

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Dharmendra Kumar (ed.) [Belgian Nuclear Research Centre (SCK.CEN), Mol (Belgium). Radiological Impact and Performance Assessment Division

    2013-11-01

    A valuable source of information for scientists in the field of environmental pollution and remediation. Describes the latest biotechnological methods for the treatment of contaminated soils. Includes case studies and protocols. Phytoremediation is an emerging technology that employs higher plants for the clean-up of contaminated environments. Basic and applied research have unequivocally demonstrated that selected plant species possess the genetic potential to accumulate, degrade, metabolize and immobilize a wide range of contaminants. The main focus of this volume is on the recent advances of technologies using green plants for remediation of various metals and metalloids. Topics include biomonitoring of heavy metal pollution, amendments of higher uptake of toxic metals, transport of heavy metals in plants, and toxicity mechanisms. Further chapters discuss agro-technological methods for minimizing pollution while improving soil quality, transgenic approaches to heavy metal remediation and present protocols for metal remediation via in vitro root cultures.

  8. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Gunnison, Colorado

    International Nuclear Information System (INIS)

    1992-10-01

    To achieve compliance with the proposed US Environmental Protection Agency (EPA) groundwater protection standards the US Department of Energy (DOE) proposes to meet background concentrations or the EPA maximum concentration limits (MCLS) for hazardous constituents in groundwater in the uppermost aquifer at the point of compliance (POC) at the Gunnison Uranium Mill Tailings Remedial Action (UMTRA) Project disposal site near Gunnison, Colorado. The proposed remedial action will ensure protection of human health and the environment. A summary of the principal features of the water resources protection strategy for the Gunnison disposal site is included in this report

  9. Sustainable Technologies and Social Costs for Eliminating Contamination of an Aquifer

    Directory of Open Access Journals (Sweden)

    Mario Schirmer

    2010-07-01

    Full Text Available This case study deals with long-term contamination of the Leuna aquifer, which is intended to be restored using sustainable technologies financed by the state. The contamination can only be solved using active rather than passive intervention, because the aquifer has an extraordinarily low natural attenuation capacity for the specific pollutants. Due to the longevity of the contamination source, the groundwater treatment technology that was chosen for the site must operate for a minimum of 20 years but probably much longer. Since the polluter-pay principle cannot be applied, the estimated dynamic primary remediation costs must be accepted as a political or social cost, which must be paid by current and future generations.

  10. Characterization of Uranium Contamination, Transport, and Remediation at Rocky Flats - Across Remediation into Post-Closure

    Science.gov (United States)

    Janecky, D. R.; Boylan, J.; Murrell, M. T.

    2009-12-01

    The Rocky Flats Site is a former nuclear weapons production facility approximately 16 miles northwest of Denver, Colorado. Built in 1952 and operated by the Atomic Energy Commission and then Department of Energy, the Site was remediated and closed in 2005, and is currently undergoing long-term surveillance and monitoring by the DOE Office of Legacy Management. Areas of contamination resulted from roughly fifty years of operation. Of greatest interest, surface soils were contaminated with plutonium, americium, and uranium; groundwater was contaminated with chlorinated solvents, uranium, and nitrates; and surface waters, as recipients of runoff and shallow groundwater discharge, have been contaminated by transport from both regimes. A region of economic mineralization that has been referred to as the Colorado Mineral Belt is nearby, and the Schwartzwalder uranium mine is approximately five miles upgradient of the Site. Background uranium concentrations are therefore elevated in many areas. Weapons-related activities included work with enriched and depleted uranium, contributing anthropogenic content to the environment. Using high-resolution isotopic analyses, Site-related contamination can be distinguished from natural uranium in water samples. This has been instrumental in defining remedy components, and long-term monitoring and surveillance strategies. Rocky Flats hydrology interlinks surface waters and shallow groundwater (which is very limited in volume and vertical and horizontal extent). Surface water transport pathways include several streams, constructed ponds, and facility surfaces. Shallow groundwater has no demonstrated connection to deep aquifers, and includes natural preferential pathways resulting primarily from porosity in the Rocky Flats alluvium, weathered bedrock, and discontinuous sandstones. In addition, building footings, drains, trenches, and remedial systems provide pathways for transport at the site. Removal of impermeable surfaces (buildings

  11. Overview of the Ogallala Aquifer Program

    Science.gov (United States)

    Irrigation increased markedly on the Southern High Plains during the second half of the 20th century, drawing water primarily from the Ogallala Aquifer. During this time, irrigation sustained regional farm incomes and rural economies. Withdrawals from the aquifer, however, have exceeded recharge, re...

  12. Hydrogeochemical analysis for Tasuj plain aquifer, Iran

    Indian Academy of Sciences (India)

    Therefore, groundwater quality monitoring and protection are essential to sustain the Tasuj plain aquifer. For this purpose, a fundamental understanding of hydrogeochemi- cal processes and hydrogeological conditions for an aquifer system is important (Adams et al. 2001;. Keywords. Graphical method; hydrogeochemistry ...

  13. Geohydrology of the Cerro Prieto geothermal aquifer

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez R, J.; de la Pena L, A.

    1981-01-01

    The most recent information on the Cerro Prieto geothermal aquifer is summarized, with special emphasis on the initial production zone where the wells completed in the Alpha aquifer are located. These wells produce steam for power plant units 1 and 2. Brief comments also are made on the Beta aquifer, which underlies the Alpha aquifer in the Cerro Prieto I area and which extends to the east to what is known as the Cerro Prieto II and Cerro Prieto III areas. The location of the area studied is shown. The Alpha and Beta aquifers differ in their mineralogy and cementing mineral composition, temperatures, and piezometric levels. The difference in piezometric levels indicates that there is no local communication between the two aquifers. This situation has been verified by a well interference test, using well E-1 as a producer in the Beta aquifer and well M-46 as the observation well in the Alpha aquifer. No interference between them was observed. Information on the geology, geohydrology, and geochemistry of Cerro Prieto is presented.

  14. Implementation of a funnel-and-gate remediation system

    International Nuclear Information System (INIS)

    O'Brien, K.; Keyes, G.; Sherman, N.

    1997-01-01

    A funnel-and-gate trademark system incorporating activated carbon was deemed the most attractive remediation method for an active lumber mill in the western United States. Petroleum hydrocarbons, chlorinated solvents, pentachlorophenol, and tetrachlorophenol were detected in on-site groundwater samples. The shallow aquifer consists of a heterogeneous mixture of marine deposits and artificial fill, underlain by low-permeability siltstones and mudstone. In the funnel-and-gate trademark system, a low-permeability cutoff wall was installed to funnel groundwater flow to a smaller area (a open-quotes gateclose quotes) where a passive below-grade treatment system treats the plume as it flows through the gate. Groundwater flow modeling focused on the inhomogeneities of the aquifer and the spatial relationship between gate(s) and barrier walls. The gate design incorporates several factors, including contaminant concentration, flow rate, and time between carbon changeouts. To minimize back pressure and maximize residence time, each gate was designed using 1.25-meter (4-foot) diameter corrugated metal pipe filled with a 1.25-meter (4-foot) thick bed of activated carbon. The configuration will allow water to flow through the treatment gates without pumps. The installed system is 190 meters (625 feet) long and treats approximately 76 L/min (20 gpm) during the winter months

  15. In-situ arsenic remediation in Carson Valley, Douglas County, west-central Nevada

    Science.gov (United States)

    Paul, Angela P.; Maurer, Douglas K.; Stollenwerk, Kenneth G.; Welch, Alan H.

    2010-01-01

    Conventional arsenic remediation strategies primarily involve above-ground treatment that include costs involved in the disposal of sludge material. The primary advantages of in-situ remediation are that building and maintaining a large treatment facility are not necessary and that costs associated with the disposal of sludge are eliminated. A two-phase study was implemented to address the feasibility of in-situ arsenic remediation in Douglas County, Nevada. Arsenic concentrations in groundwater within Douglas County range from 1 to 85 micrograms per liter. The primary arsenic species in groundwater at greater than 250 ft from land surface is arsenite; however, in the upper 150 ft of the aquifer arsenate predominates. Where arsenite is the primary form of arsenic, the oxidation of arsenite to arsenate is necessary. The results of the first phase of this investigation indicated that arsenic concentrations can be remediated to below the drinking-water standard using aeration, chlorination, iron, and pH adjustment. Arsenic concentrations were remediated to less than 10 micrograms per liter in groundwater from the shallow and deep aquifer when iron concentrations of 3-6 milligrams per liter and pH adjustments to less than 6 were used. Because of the rapid depletion of dissolved oxygen, the secondary drinking-water standards for iron (300 micrograms per liter) and manganese (100 micrograms per liter) were exceeded during treatment. Treatment was more effective in the shallow well as indicated by a greater recovery of water meeting the arsenic standard. Laboratory and field tests were included in the second phase of this study. Laboratory column experiments using aquifer material indicated the treatment process followed during the first phase of this study will continue to work, without exceeding secondary drinking-water standards, provided that groundwater was pre-aerated and an adequate number of pore volumes treated. During the 147-day laboratory experiment, no

  16. HANFORD GROUNDWATER REMEDIATION

    Energy Technology Data Exchange (ETDEWEB)

    CHARBONEAU, B; THOMPSON, M; WILDE, R.; FORD, B.; GERBER, M.S.

    2006-02-01

    geographically dispersed community is united in its desire to protect the Columbia River and have a voice in Hanford's future. This paper presents the challenges, and then discusses the progress and efforts underway to reduce the risk posed by contaminated groundwater at Hanford. While Hanford groundwater is not a source of drinking water on or off the Site, there are possible near-shore impacts where it flows into the Columbia River. Therefore, this remediation is critical to the overall efforts to clean up the Site, as well as protect a natural resource.

  17. Economics of Managed Aquifer Recharge

    Directory of Open Access Journals (Sweden)

    Robert G. Maliva

    2014-05-01

    Full Text Available Managed aquifer recharge (MAR technologies can provide a variety of water resources management benefits by increasing the volume of stored water and improving water quality through natural aquifer treatment processes. Implementation of MAR is often hampered by the absence of a clear economic case for the investment to construct and operate the systems. Economic feasibility can be evaluated using cost benefit analysis (CBA, with the challenge of monetizing benefits. The value of water stored or treated by MAR systems can be evaluated by direct and indirect measures of willingness to pay including market price, alternative cost, value marginal product, damage cost avoided, and contingent value methods. CBAs need to incorporate potential risks and uncertainties, such as failure to meet performance objectives. MAR projects involving high value uses, such as potable supply, tend to be economically feasible provided that local hydrogeologic conditions are favorable. They need to have low construction and operational costs for lesser value uses, such as some irrigation. Such systems should therefore be financed by project beneficiaries, but dichotomies may exist between beneficiaries and payers. Hence, MAR projects in developing countries may be economically viable, but external support is often required because of limited local financial resources.

  18. Radon remediation in irish schools

    International Nuclear Information System (INIS)

    Synnott, H.

    2006-01-01

    Full text: Commencing in 1998, the Radiological Protection Institute of Ireland carried out radon measurements in 3826 schools in the Republic of I reland on behalf of the Irish Department of Education and Science (D.E.S.). This represents approximately 97% of all schools in the country. Approximately 25% (984) schools had radon concentrations above the Irish national schools Reference Level for radon of 200 Bq/m 3 and required remedial work. The number of individual rooms with radon concentrations above 200 Bq/m 3 was 3020. Remedial work in schools commenced in early 2000. In general schools with maximum radon concentrations in the range 200 -400 Bq/m 3 in one or more rooms were remediated through the installation of passive systems such as an increase in permanent background ventilation mainly wall vents and trickle vents in windows. Schools with maximum radon concentrations greater than 400 Bq/m 3 were usually remediated through the provision of active systems mainly fan assisted sub -slab de pressurization or where this was not possible fan assisted under floor ventilation. The cost of the remedial programme was funded by central Government. Active systems were installed by specialized remedial contractors working to the specifications of a radon remedial expert appointed by the D.E.S. to design remedial systems for affected schools. Schools requiring increased ventilation were granted aided 190 pounds per affected room and had to organize the work themselves. In most schools radon remediation was successful in reducing existing radon concentrations to below the Reference Level. Average radon concentration reduction factors for sub-slab de pressurization systems and fan assisted fan assisted under floor ventilation ranged from 5 to 40 with greater reduction rates found at higher original radon concentrations. Increasing ventilation in locations with moderately elevated radon concentrations (200 - 400 Bq/m 3 ) while not as effective as active systems produced on

  19. The benefits from environmental remediation

    International Nuclear Information System (INIS)

    Falck, W.E.

    2002-01-01

    Environmental remediation projects inevitably take place against a backdrop of overall social goals and values. These goals can include, for example, full employment, preservation of the cultural, economic and archaeological resources, traditional patterns of land use, spiritual values, quality of life factors, biological diversity, environmental and socio-economic sustainability, protection of public health. Different countries will have different priorities, linked to the overall set of societal goals and the availability of resources, including funding, man-power and skills. These issues are embedded within both a national and local socio-cultural context, and will shape the way in which the remediation process is structured in any one country. The context will shape both the overall objectives of a remediation activity within the framework of competing societal goals, as well as generate constraints on the decision making process. Hence, the overall benefit of a remediation project is determined by its overall efficiency and effectiveness within the given legal, institutional, and governance framework, under the prevailing socio-economic boundary conditions, and balancing technology performance and risk reduction with fixed or limited budgetary resources, and is not simply the result of the technical remediation operation itself. (author)

  20. The Role of Attached and Free-Living Bacteria in Biodegradation in Karst Aquifers

    Directory of Open Access Journals (Sweden)

    Ahmad Kheder

    2011-12-01

    Full Text Available Natural attenuation of groundwater contamination occurs at some level for all aquifers impacted with organic contaminants. The issues regarding natural attenuation are whether it takes place at a sufficient rate to be protective of human health and the environment. Implementation of a Monitored Natural Attenuation (MNA remedial alternative for groundwater requires parties responsible for the contamination to demonstrate to regulators and the public that MNA is protective at a given site. Analysis of MNA for remediation of karst aquifers is hampered by a lack of understanding of biodegradation in karst environments. The lack of studies examining biodegradation in karst aquifers may in large part be due to the widespread perception that contaminants are rapidly flushed out of karst aquifers resulting in insufficient residence times for contaminants to biodegrade. In highly developed and well-connected conduit systems, the rate of contaminant migration is perceived to be much faster than the rate of biodegradation. This perception of contaminant transport is largely incorrect. Tracer studies for karst aquifers often indicate that these aquifers are characterized by diverse flow regimes and storage capabilities. Additionally, it is also believed that if bioremediation in bedrock aquifers is dependent upon contact between surface-attached bacteria and contaminants, then bioremediation would be limited by the low surface-area-to-volume ratio (SA/V of karst aquifers. A quantitative basis, however, for accepting or rejecting the assumption that attached bacteria dominate the biodegradation process in karst conduits has not been shown. The objective of this research was to determine if free-living karst bacteria from contributed as much to toluene biodegradation as attached bacteria. This is an important area of research. Research indicates bacteria are both attached and free-living in karst aquifers and it is unrealistic to think that only the attached

  1. Remediation Technologies Eliminate Contaminants

    Science.gov (United States)

    2012-01-01

    groundwater tainted by chlorinated solvents once used to clean rocket engine components. The award-winning innovation (Spinoff 2010) is now NASA s most licensed technology to date. PCBs in paint presented a new challenge. Removing the launch stand for recycling proved a difficult operation; the toxic paint had to be fully stripped from the steel structure, a lengthy and costly process that required the stripped paint to be treated before disposal. Noting the lack of efficient, environmentally friendly options for dealing with PCBs, Quinn and her colleagues developed the Activated Metal Treatment System (AMTS). AMTS is a paste consisting of a solvent solution containing microscale particles of activated zero-valent metal. When applied to a painted surface, the paste extracts and degrades the PCBs into benign byproducts while leaving the paint on the structure. This provides a superior alternative to other methods for PCB remediation, such as stripping the paint or incinerating the structure, which prevents reuse and can release volatized PCBs into the air. Since its development, AMTS has proven to be a valuable solution for removing PCBs from paint, caulking, and various insulation and filler materials in older buildings, naval ships, and former munitions facilities where the presence of PCBs interferes with methods for removing trace explosive materials. Miles of potentially toxic caulking join sections of runways at airports. Any of these materials installed before 1979 potentially contain PCBs, Quinn says. "This is not just a NASA problem," she says. "It s a global problem."

  2. A remedial alternative prioritization method

    International Nuclear Information System (INIS)

    Richter, S.A.; Travis, C.C.

    1987-01-01

    This study develops and tests a technique for evaluating and prioritizing alternative remedial actions for hazardous waste sites. The method is based on criteria involving risk, benefit and cost, and identifies the most cost-effective solution to a given remedial problem. Four sites on the Department of Energy's Oak Ridge National Laboratory (ORNL) property in Oak Ridge, Tennessee, were used in a case study to develop and test the method. Results of the case study indicate that even if the cap providing in situ containment must be replaced every 10 years, it is a superior alternative to total excavation of the waste sites

  3. Funnel-and-gate remediation systems augmented with passive filter wells.

    Science.gov (United States)

    Hudak, Paul F

    2010-09-01

    The objective of this study was to evaluate the ability of funnel-and-gate structures augmented with passive wells containing filter cartridges to capture contaminated groundwater in hypothetical, homogeneous and heterogeneous, unconfined aquifers. Perpendicular to groundwater flow, linear structures were 15 m wide, 1 m thick, and keyed into the base of the aquifer. Gates occupied 4 m of the total width of each simulated structure; one gate was 5 m from a contaminant plume's leading tip, while others occupied cross-gradient margins of the plume. Results suggest a modest reduction in remediation timeframes, up to 425 d per well added in these simulations; however, incremental benefits are highly variable and case specific.

  4. Basement and alluvial aquifers of Malawi: An overview of ...

    African Journals Online (AJOL)

    This paper highlights the quality of groundwater in basement and alluvial aquifers of Malawi through literature assessment. Groundwater in these aquifers serves about 60% of Malawian population. Alluvial aquifers yield high groundwater in excess of 10 L/s and more mineralized than basement aquifers. The values from ...

  5. Hydrology of the Claiborne aquifer and interconnection with the Upper Floridan aquifer in southwest Georgia

    Science.gov (United States)

    Gordon, Debbie W.; Gonthier, Gerard

    2017-04-24

    The U.S. Geological Survey conducted a study, in cooperation with the Georgia Environmental Protection Division, to define the hydrologic properties of the Claiborne aquifer and evaluate its connection with the Upper Floridan aquifer in southwest Georgia. The effort involved collecting and compiling hydrologic data from the aquifer in subarea 4 of southwestern Georgia. Data collected for this study include borehole geophysical logs in 7 wells, and two 72-hour aquifer tests to determine aquifer properties.The top of the Claiborne aquifer extends from an altitude of about 200 feet above the North American Vertical Datum of 1988 (NAVD 88) in Terrell County to 402 feet below NAVD 88 in Decatur County, Georgia. The base of the aquifer extends from an altitude of about 60 feet above NAVD 88 in eastern Sumter County to about 750 feet below NAVD 88 in Decatur County. Aquifer thickness ranges from about 70 feet in eastern Early County to 400 feet in Decatur County.The transmissivity of the Claiborne aquifer, determined from two 72-hour aquifer tests, was estimated to be 1,500 and 700 feet squared per day in Mitchell and Early Counties, respectively. The storage coefficient was estimated to be 0.0006 and 0.0004 for the same sites, respectively. Aquifer test data from Mitchell County indicate a small amount of leakage occurred during the test. Groundwater-flow models suggest that the source of the leakage was the underlying Clayton aquifer, which produced about 2.5 feet of drawdown in response to pumping in the Claiborne aquifer. The vertical hydraulic conductivity of the confining unit between the Claiborne and Clayton aquifers was simulated to be about 0.02 foot per day.Results from the 72-hour aquifer tests run for this study indicated no interconnection between the Claiborne and overlying Upper Floridan aquifers at the two test sites. Additional data are needed to monitor the effects that increased withdrawals from the Claiborne aquifer may have on future water resources.

  6. Hydrodynamic analysis application of contaminated groundwater remediation to oil hydrocarbons

    Directory of Open Access Journals (Sweden)

    Pajić Predrag R.

    2017-01-01

    Full Text Available In this paper, the application of the hydrodynamic analysis in the selected ‘pumping and treatment’ remediation method of groundwater hydrocarbon pollution in the case of the Pancevo oil refinery is examined. The applied hydrodynamic analysis represents a regular and necessary approach in modern hydrogeology. Previous chemical analysis of soil and groundwater samples at observation objects revealed their pollution by oil products. New researches included the constraction of 12 piezometric boreholes of varying depths, geoelectric soil sounding, ‘in situ’ measurement of the present contaminant, detected as a hydrophobic phase of LNAPL, chemical analysis of soil and groundwater samples with emphasis on total petroleum hydrocarbons (TPH content, total fats and mineral oils, mercury cations and other characteristic compounds, etc. These researches define the volume of contamination issued by the ‘light’ (LNAPL contamination phase. The selected remediation method for this type of pollution is the ‘Pump and Treat’ method, which implies the pumping of contaminated groundwater from aquifer and their subsequent treatment. A hydrodynamic method was used to select the optimal hydrotechnical solution for LNAPL extraction. On the mathematical model, the prediction calculations for two variant solutions were carried out (‘hydraulic isolation’ and complex for the application of groundwater contamination remediation characterized as front pollution substance (by extraction and injection wells or infiltration pool. By extraction wells performing, it would be possible to remove the LNAPL from the surface of the water with special pumps-skimmers. The importance of the hydrodynamic method application is, in addition to the hydrotechnical solution selection for the LNAPL drainage, the provision of quality basis for the dimensioning of these objects based on the results of the groundwater balance.

  7. Caresoil: A multidisciplinar Project to characterize, remediate, monitor and evaluate the risk of contaminated soils in Madrid (Spain)

    Science.gov (United States)

    Muñoz-Martín, Alfonso; Antón, Loreto; Granja, Jose Luis; Villarroya, Fermín; Montero, Esperanza; Rodríguez, Vanesa

    2016-04-01

    Soil contamination can come from diffuse sources (air deposition, agriculture, etc.) or local sources, these last being related to anthropogenic activities that are potentially soil contaminating activities. According to data from the EU, in Spain, and particularly for the Autonomous Community of Madrid, it can be considered that heavy metals, toxic organic compounds (including Non Aqueous Phases Liquids, NAPLs) and combinations of both are the main problem of point sources of soil contamination in our community. The five aspects that will be applied in Caresoil Program (S2013/MAE-2739) in the analysis and remediation of a local soil contamination are: 1) the location of the source of contamination and characterization of soil and aquifer concerned, 2) evaluation of the dispersion of the plume, 3) application of effective remediation techniques, 4) monitoring the evolution of the contaminated soil and 5) risk analysis throughout this process. These aspects involve advanced technologies (hydrogeology, geophysics, geochemistry,...) that require new developing of knowledge, being necessary the contribution of several researching groups specialized in the fields previously cited, as they are those integrating CARESOIL Program. Actually two cases concerning hydrocarbon spills, as representative examples of soil local contamination in Madrid area, are being studied. The first is being remediated and we are monitoring this process to evaluate its effectiveness. In the second location we are defining the extent of contamination in soil and aquifer to define the most effective remediation technique.

  8. Electrokinetic remediation of copper mine tailings

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Rojo, Adrián; Ottosen, Lisbeth M.

    2007-01-01

    in similar experiments but without the bipolar electrodes. The new electrokinetic remediation design was tested on copper mine tailings with different applied electric fields, remediation times and pre-treatment. The results showed that the copper removal was increased from 8% (applying 20V for 8 days......Important process parameters to optimize in electrokinetic soil remediation are those influencing remediation time and power consumption since these directly affect the cost of a remediation action. This work shows how the electrokinetic remediation (EKR) process could be improved by implementing...... bipolar electrodes in the porous material. The bipolar electrodes in EKR meant two improvements: (1) a shorter migration pathway for the contaminant, and (2) an increased electrical conductivity in the remediation system. All together the remediation proceeded faster with lower electrical resistance than...

  9. Key Principles of Superfund Remedy Selection

    Science.gov (United States)

    Guidance on the primary considerations of remedy selection which are universally applicable at Superfund sites. Key guidance here include: Rules of Thumb for Superfund Remedy Selection and Role of the Baseline Risk Assessment.

  10. Estimated withdrawals from principal aquifers in the United States, 2000

    Science.gov (United States)

    Maupin, Molly A.; Barber, Nancy L.

    2005-01-01

    Fresh ground-water withdrawals from 66 principal aquifers in the United States were estimated for irrigation, public-supply, and self-supplied industrial water uses for the year 2000. Total ground-water withdrawals were 76,500 million gallons per day, or 85,800 thousand acre-feet per year for these three uses. Irrigation used the largest amount of ground water, 56,900 million gallons per day, followed by public supply with 16,000 million gallons per day, and self-supplied industrial with 3,570 million gallons per day. These three water uses represented 92 percent of the fresh groundwater withdrawals for all uses in the United States, the remaining 8 percent included self-supplied domestic, aquaculture, livestock, mining, and thermoelectric power uses. Aquifer withdrawals were categorized by five lithologic groups: unconsolidated and semiconsolidated sand and gravel aquifers, carbonate-rock aquifers, igneous and metamorphic-rock aquifers, sandstone aquifers, and sandstone and carbonate-rock aquifers. Withdrawals from aquifers that were not included in one of the 66 principal aquifers were reported in an “Other” aquifers group. The largest withdrawals in the United States were from unconsolidated and semiconsolidated sand and gravel aquifers, which accounted for 80 percent of total withdrawals from all aquifers. Carbonate-rock aquifers provided 8 percent of the withdrawals, and igneous and metamorphic-rock aquifers, 6 percent. Withdrawals from sandstone aquifers, from sandstone and carbonate-rock aquifers, and from the “Other” aquifers category each constituted about 2 percent of the total withdrawals reported.Fifty-five percent of the total withdrawals for irrigation, public-supply, and self-supplied industrial water uses were provided by the High Plains aquifer, California Central Valley aquifer system, the Mississippi River Valley alluvial aquifer, and the Basin and Range basin-fill aquifers. These aquifers provided most of the withdrawals for irrigation

  11. Laboratory and pilot field-scale testing of surfactants for environmental restoration of chlorinated solvent DNAPLs

    International Nuclear Information System (INIS)

    Jackson, R.E.; Fountain, J.C.

    1994-01-01

    This project is composed of two phases and has the objective of demonstrating surfactant-enhanced aquifer remediation (SEAR) as a practical remediation technology at DOE sites with ground water contaminated by dense, non-aqueous phase liquids (DNAPLs), in particular, chlorinated solvents. The first phase of this project, Laboratory and Pilot Field Scale Testing, which is the subject of the work so far, involves (1) laboratory experiments to examine the solubilization of multiple component DNAPLs, e.g., solvents such as perchloroethylene (PCE) and trichloroethylene (TCE), by dilute surfactant solutions, and (2) a field test to demonstrate SEAR technology on a small scale and in an existing well

  12. Radial Dupuit interface flow to assess the aquifer storage and recovery potential of saltwater aquifers

    OpenAIRE

    Bakker, M.

    2009-01-01

    A new accurate numerical solution is presented for aquifer storage and recovery (ASR) systems in coastal aquifers; flow is approximated as radial Dupuit interface flow. The radial velocities of points on the interface are a function of time, the vertical coordinate, and the dimensionless parameter D (the discharge of the well divided by the product of the hydraulic conductivity, the square of the aquifer thickness, and the dimensionless density difference). The recovery efficiency of an ASR s...

  13. Influence of aquifer heterogeneity on the design and modelling of Aquifer Thermal Energy Storage (ATES) systems

    OpenAIRE

    Bridger, David W.

    2006-01-01

    A modelling study was carried out to evaluate the influence of aquifer heterogeneity, as represented by geologic layering, on heat transport and storage in aquifer thermal energy storage (ATES) systems. An existing ATES system installed within a heterogeneous aquifer system in Agassiz, British Columbia, Canada was used as a case study. Two 3D heat transport models of the study site were developed and calibrated using the heat transport code FEFLOW, including: a "simple" model domain with unif...

  14. Green Chemistry and Environmental Remediation

    Science.gov (United States)

    Abstract: Nutrient remediation and recovery is a growing concern for two key reasons: (i) the prevention of harmful algal bloom proliferation, and (ii) the recycling of nutrients (e.g., phosphates) as they are non-renewable resources which are quickly being depleted. A wide range...

  15. Electrodialytic Remediation of Copper Mine Tailings

    DEFF Research Database (Denmark)

    Hansen, H.K.; Rojo, A.; Ottosen, L.M.

    2012-01-01

    This work compares and evaluates sixteen electrodialytic laboratory remediation experiments on copper mine tailings. Different parameters were analysed, such as remediation time, addition of desorbing agents, and the use of pulsed electrical fields.......This work compares and evaluates sixteen electrodialytic laboratory remediation experiments on copper mine tailings. Different parameters were analysed, such as remediation time, addition of desorbing agents, and the use of pulsed electrical fields....

  16. Digital data sets that describe aquifer characteristics of the Enid isolated terrace aquifer in northwestern Oklahoma

    Science.gov (United States)

    Becker, C.J.; Runkle, D.L.; Rea, Alan

    1997-01-01

    ARC/INFO export and nonproprietary format files The data sets in this report include digitized aquifer boundaries and maps of hydraulic conductivity, recharge, and ground-water level elevation contours for the Enid isolated terrace aquifer in northwestern Oklahoma. The Enid isolated terrace aquifer covers approximately 82 square miles and supplies water for irrigation, domestic, municipal, and industrial use for the City of Enid and western Garfield County. The Quaternary-age Enid isolated terrace aquifer is composed of terrace deposits that consist of discontinuous layers of clay, sandy clay, sand, and gravel. The aquifer is unconfined and is bounded by the underlying Permian-age Hennessey Group on the east and the Cedar Hills Sandstone Formation of the Permian-age El Reno Group on the west. The Cedar Hills Sandstone Formation fills a channel beneath the thickest section of the Enid isolated terrace aquifer in the midwestern part of the aquifer. All of the data sets were digitized and created from information and maps in a ground-water modeling thesis and report of the Enid isolated terrace aquifer. The maps digitized were published at a scale of 1:62,500. Ground-water flow models are numerical representations that simplify and aggregate natural systems. Models are not unique; different combinations of aquifer characteristics may produce similar results. Therefore, values of hydraulic conductivity and recharge used in the model and presented in this data set are not precise, but are within a reasonable range when compared to independently collected data.

  17. DoD Green Remediation Policy Update

    Science.gov (United States)

    2011-05-11

    decisions and practices  Green remediation is the practice of considering all environmental effects of remedy implementation and incorporating... reforestation irrigation – More than 30,000 tons of soil remediated and 270 tons of lead bullet fragments were reclaimed for recycling  Footprint Reduction

  18. 40 CFR 92.705 - Remedial plan.

    Science.gov (United States)

    2010-07-01

    ... POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Recall Regulations § 92.705 Remedial plan. (a) When any... repair under the remedial plan to affix a label to each locomotive or locomotive engine repaired or, when... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Remedial plan. 92.705 Section 92.705...

  19. New Mexico English Remediation Taskforce Report

    Science.gov (United States)

    New Mexico Higher Education Department, 2016

    2016-01-01

    In March, 2016, the state of New Mexico established a Remediation Task Force to examine remediation reform efforts across the state's higher education institutions. On March 11, the Task Force met for the "New Mexico Corequisite Remediation at Scale Policy Institute" in order to learn about the results of the latest national reform…

  20. Development Report on the Idaho National Laboratory Sitewide Three-Dimensional Aquifer Model

    Energy Technology Data Exchange (ETDEWEB)

    Thomas R. Wood; Catherine M. Helm-Clark; Hai Huang; Swen Magnuson; Travis McLing; Brennon Orr; Michael J. Rohe; Mitchell A. Plummer; Robert Podgorney; Erik Whitmore; Michael S. Roddy

    2007-09-01

    A sub-regional scale, three-dimensional flow model of the Snake River Plain Aquifer was developed to support remediation decisions for Waste Area Group 10, Operable Unit 10 08 at the Idaho National Laboratory (INL) Site. This model has been calibrated primarily to water levels and secondarily to groundwater velocities interpreted from stable isotope disequilibrium studies and the movement of anthropogenic contaminants in the aquifer from facilities at the INL. The three-dimensional flow model described in this report is one step in the process of constructing a fully three-dimensional groundwater flow and contaminant transport model as prescribed in the Idaho National Engineering and Environmental Laboratory Operable Unit 10-08 Sitewide Groundwater Model Work Plan. An updated three-dimensional hydrogeologic conceptual model is presented along with the geologic basis for the conceptual model. Sediment-dominated three-dimensional volumes were used to represent the geology and constrain groundwater flow as part of the conceptual model. Hydrological, geochemical, and geological data were summarized and evaluated to infer aquifer behavior. A primary observation from development and evaluation of the conceptual model was that relative to flow on a regional scale, the aquifer can be treated with steady-state conditions. Boundary conditions developed for the three-dimensional flow model are presented along with inverse simulations that estimate parameterization of hydraulic conductivity. Inverse simulations were performed using the pilot-point method to estimate permeability distributions. Thermal modeling at the regional aquifer scale and at the sub-regional scale using the inverted permeabilities is presented to corroborate the results of the flow model. The results from the flow model show good agreement with simulated and observed water levels almost always within 1 meter. Simulated velocities show generally good agreement with some discrepancies in an interpreted low

  1. Hydrogeologic characterization of devonian aquifers in Uruguay

    International Nuclear Information System (INIS)

    Massa, E.

    1988-01-01

    This article carried out the assistance research project implementation in devonian sedimentary units as a potentials aquifers and their best use to school supplying and rural population in central area of Uruguay.

  2. Estimated Withdrawals from Stream-Valley Aquifers and Refined Estimated Withdrawals from Selected Aquifers in the United States, 2000

    Science.gov (United States)

    Sargent, B. Pierre; Maupin, Molly A.; Hinkle, Stephen R.

    2008-01-01

    The U.S. Geological Survey National Water Use Information Program compiles estimates of fresh ground-water withdrawals in the United States on a 5-year interval. In the year-2000 compilation, withdrawals were reported from principal aquifers and aquifer systems including two general aquifers - Alluvial and Other aquifers. Withdrawals from a widespread aquifer group - stream-valley aquifers - were not specifically identified in the year-2000 compilation, but they are important sources of ground water. Stream-valley aquifers are alluvial aquifers located in the valley of major streams and rivers. Stream-valley aquifers are long but narrow aquifers that are in direct hydraulic connection with associated streams and limited in extent compared to most principal aquifers. Based in large part on information published in U.S. Geological Survey reports, preliminary analysis of withdrawal data and hydrogeologic and surface-water information indicated areas in the United States where possible stream-valley aquifers were located. Further assessment focused on 24 states and the Commonwealth of Puerto Rico. Withdrawals reported from Alluvial aquifers in 16 states and withdrawals reported from Other aquifers in 6 states and the Commonwealth of Puerto Rico were investigated. Two additional States - Arkansas and New Jersey - were investigated because withdrawals reported from other principal aquifers in these two States may be from stream-valley aquifers. Withdrawals from stream-valley aquifers were identified in 20 States and were about 1,560 Mgal/d (million gallons per day), a rate comparable to withdrawals from the 10 most productive principal aquifers in the United States. Of the 1,560 Mgal/d of withdrawals attributed to stream-valley aquifers, 1,240 Mgal/d were disaggregated from Alluvial aquifers, 150 Mgal/d from glacial sand and gravel aquifers, 116 Mgal/d from Other aquifers, 28.1 Mgal/d from Pennsylvanian aquifers, and 24.9 Mgal/d from the Mississippi River Valley alluvial

  3. Optimal design of active spreading systems to remediate sorbing groundwater contaminants in situ.

    Science.gov (United States)

    Piscopo, Amy N; Neupauer, Roseanna M; Kasprzyk, Joseph R

    2016-07-01

    The effectiveness of in situ remediation to treat contaminated aquifers is limited by the degree of contact between the injected treatment chemical and the groundwater contaminant. In this study, candidate designs that actively spread the treatment chemical into the contaminant are generated using a multi-objective evolutionary algorithm. Design parameters pertaining to the amount of treatment chemical and the duration and rate of its injection are optimized according to objectives established for the remediation - maximizing contaminant degradation while minimizing energy and material requirements. Because groundwater contaminants have different reaction and sorption properties that influence their ability to be degraded with in situ remediation, optimization was conducted for six different combinations of reaction rate coefficients and sorption rates constants to represent remediation of the common groundwater contaminants, trichloroethene, tetrachloroethene, and toluene, using the treatment chemical, permanganate. Results indicate that active spreading for contaminants with low reaction rate coefficients should be conducted by using greater amounts of treatment chemical mass and longer injection durations relative to contaminants with high reaction rate coefficients. For contaminants with slow sorption or contaminants in heterogeneous aquifers, two different design strategies are acceptable - one that injects high concentrations of treatment chemical mass over a short duration or one that injects lower concentrations of treatment chemical mass over a long duration. Thus, decision-makers can select a strategy according to their preference for material or energy use. Finally, for scenarios with high ambient groundwater velocities, the injection rate used for active spreading should be high enough for the groundwater divide to encompass the entire contaminant plume. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Enhancing aquifer cleanup with reinjection

    International Nuclear Information System (INIS)

    Isherwood, W.F.; Ziagos, J.; Rice, D. Jr.; Krauter, P.; Nichols, E.

    1992-09-01

    Injection of water or steam, with or without chemical surfactants, is a common petroleum industry technique to enhance product recovery. In the geothermal industry, reinjection (reinjection is used to mean the injection of ground water that was previously injected) of heat- depleted subsurface fluids is commonly used to maintain reservoir pressure, thus prolonging field productivity. The use reinjection in ground-water remediation projects allows for the application of both traditional production field management and a variety of additional enhancements to the cleanup process. Development of the ideas in this paper was stimulated by an initial suggestion by Dr. Jacob Bear (personal discussions, 1990--1991) that reinjected water might be heated to aid the desorption process

  5. Remediation using trace element humate surfactant

    Science.gov (United States)

    Riddle, Catherine Lynn; Taylor, Steven Cheney; Bruhn, Debra Fox

    2016-08-30

    A method of remediation at a remediation site having one or more undesirable conditions in which one or more soil characteristics, preferably soil pH and/or elemental concentrations, are measured at a remediation site. A trace element humate surfactant composition is prepared comprising a humate solution, element solution and at least one surfactant. The prepared trace element humate surfactant composition is then dispensed onto the remediation site whereby the trace element humate surfactant composition will reduce the amount of undesirable compounds by promoting growth of native species activity. By promoting native species activity, remediation occurs quickly and environmental impact is minimal.

  6. Digital data sets that describe aquifer characteristics of the Elk City Aquifer in western Oklahoma

    Science.gov (United States)

    Becker, C.J.; Runkle, D.L.; Rea, Alan

    1997-01-01

    ARC/INFO export and nonproprietary format files This diskette contains digitized aquifer boundaries and maps of hydraulic conductivity, recharge, and ground-water level elevation contours for the Elk City aquifer in western Oklahoma. The aquifer covers an area of approximately 193,000 acres and supplies ground water for irrigation, domestic, and industrial purposes in Beckham, Custer, Roger Mills, and Washita Counties along the divide between the Washita and Red River basins. The Elk City aquifer consists of the Elk City Sandstone and overlying terrace deposits, made up of clay, silt, sand and gravel, and dune sands in the eastern part and sand and gravel of the Ogallala Formation (or High Plains aquifer) in the western part of the aquifer. The Elk City aquifer is unconfined and composed of very friable sandstone, lightly cemented with clay, calcite, gypsum, or iron oxide. Most of the grains are fine-sized quartz but the grain size ranges from clay to cobble in the aquifer. The Doxey Shale underlies the Elk City aquifer and acts as a confining unit, restricting the downward movement of ground water. All of the data sets were digitized and created from information and maps in a ground-water modeling thesis and report of the Elk City aquifer. The maps digitized were published at a scale of 1:63,360. Ground-water flow models are numerical representations that simplify and aggregate natural systems. Models are not unique; different combinations of aquifer characteristics may produce similar results. Therefore, values of hydraulic conductivity and recharge used in the model and presented in this data set are not precise, but are within a reasonable range when compared to independently collected data.

  7. A General Solution for Groundwater Flow in Estuarine Leaky Aquifer System with Considering Aquifer Anisotropy

    Science.gov (United States)

    Chen, Po-Chia; Chuang, Mo-Hsiung; Tan, Yih-Chi

    2014-05-01

    In recent years the urban and industrial developments near the coastal area are rapid and therefore the associated population grows dramatically. More and more water demand for human activities, agriculture irrigation, and aquaculture relies on heavy pumping in coastal area. The decline of groundwater table may result in the problems of seawater intrusion and/or land subsidence. Since the 1950s, numerous studies focused on the effect of tidal fluctuation on the groundwater flow in the coastal area. Many studies concentrated on the developments of one-dimensional (1D) and two-dimensional (2D) analytical solutions describing the tide-induced head fluctuations. For example, Jacob (1950) derived an analytical solution of 1D groundwater flow in a confined aquifer with a boundary condition subject to sinusoidal oscillation. Jiao and Tang (1999) derived a 1D analytical solution of a leaky confined aquifer by considered a constant groundwater head in the overlying unconfined aquifer. Jeng et al. (2002) studied the tidal propagation in a coupled unconfined and confined costal aquifer system. Sun (1997) presented a 2D solution for groundwater response to tidal loading in an estuary. Tang and Jiao (2001) derived a 2D analytical solution in a leaky confined aquifer system near open tidal water. This study aims at developing a general analytical solution describing the head fluctuations in a 2D estuarine aquifer system consisted of an unconfined aquifer, a confined aquifer, and an aquitard between them. Both the confined and unconfined aquifers are considered to be anisotropic. The predicted head fluctuations from this solution will compare with the simulation results from the MODFLOW program. In addition, the solutions mentioned above will be shown to be special cases of the present solution. Some hypothetical cases regarding the head fluctuation in costal aquifers will be made to investigate the dynamic effects of water table fluctuation, hydrogeological conditions, and

  8. Treatment trains for the remediation of aquifers polluted with MTBE and other xenobiotic compounds

    DEFF Research Database (Denmark)

    Tsitonaki, Aikaterini

    2008-01-01

    Komplekse blandinger af forureningsstoffer, høje koncentrationer og heterogene geologiske forhold kan vanskeliggøre oprensning af forurenede grunde. Anvendelse af en aggressiv og måske dyr afværgeteknologi efterfulgt af en biologisk metode har været foreslået. Ved kombinationen af to afværgetekno...

  9. Abiotic reduction of aquifer materials by dithionite: A promising in-situ remediation technology

    International Nuclear Information System (INIS)

    Amonette, J.E.; Szecsody, J.E.; Schaef, H.T.; Gorby, Y.A.; Fruchter, J.S.; Templeton, J.C.

    1994-11-01

    Laboratory batch and column experiments were conducted with Hanford sediments to develop the capability to predict (1) the longevity of dithionite in these systems, (2) its efficiency as a reductant of structural iron, and (3) the longevity and reactivity of the reduced iron with soluble inorganic and organic species. After an initial induction period, the loss of dithionite by disproportionation and oxidation could be described by pseudo-first-order (PFO) kinetics. Other than the initial reaction with ferric iron, the primary factor promoting loss of dithionite in this system was disproportion nation via heterogeneous catalysis at mineral surfaces. The efficiency of the reduction of structural iron was nearly 100% for the first fourth of the ferric iron, but declined exponentially with higher degrees of reduction so that 75% of the ferric iron could be reduced. This decrease in reduction efficiency probably was related to differences in the accessibility of ferric iron in the mineral particles, with iron in clay-sized particles being the most accessible and that in silt- and sand-sized particles less accessible. Flow-through column studies showed that a reduced-sediment barrier created in this manner could maintain a reducing environment

  10. A game-theoretic parameter configuration technique for aquifer restoration design

    Science.gov (United States)

    Eheart, J. Wayland; Rahman, M. Rezaur; Keith, Stevan M.; Valocchi, Albert J.

    1990-10-01

    The problem of designing an active hydraulic system for remediation of a polluted aquifer is addressed for the case when parameters are not known with certainty. The design problem is cast as a game in which the protagonist-designer is pitted against an antagonist which alters the values of the uncertain parameters, within prescribed limits, so as to render the engineered system most ineffective. A solution method for the antagonist's problem, referred to as the parameter configuration technique (PCT), is developed and discussed in this paper. This technique selects spatially dependent values of the distributed parameter, transmissivity, such that the pattern of variation represents a pessimistic (but realistic) set of design conditions. The task of finding the "worst" set of parameter values is cast as a constrained optimization problem whose objective function is to thwart the remedial action design to the greatest degree possible. A rudimentary objective function is arbitrarily specified by the researchers. Several types of feasibility constraints restrict the distribution of parameter values to those combinations that are "realistic." One type limits the variogram, another type, the mean, and a third type, the trend, of the log transmissivity. The resulting optimization problem is ill-behaved; difficulty was encountered obtaining a mathematically optimal solution. However, it may not always be necessary to find such a mathematically optimal solution in order to derive practical utility from the results. Two special heuristic techniques for obtaining a near-optimal solution are discussed. The technique is applied to a hypothetical contaminated aquifer with a simple single-extraction well flushing system. The solution is compared to a Monte Carlo approach applied to the same aquifer. The required pumping rate for a pessimistic parameter set generated by the new technique is about the same as the second largest of 100 Monte Carlo realizations.

  11. Baseline mapping study of the Steed Pond aquifer and vadose zone beneath A/M Area, Savannah River Site, Aiken, South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, D.G. Jr.

    2000-01-27

    This report presents the second phase of a baseline mapping project conducted for the Environmental Restoration Department (ERD) at Savannah River Site. The purpose of this second phase is to map the structure and distribution of mud (clay and silt-sized sediment) within the vadose zone beneath A/M Area. The results presented in this report will assist future characterization and remediation activities in the vadose zone and upper aquifer zones in A/M Area.

  12. Baseline mapping study of the Steed Pond aquifer and vadose zone beneath A/M Area, Savannah River Site, Aiken, South Carolina

    International Nuclear Information System (INIS)

    Jackson, D.G. Jr.

    2000-01-01

    This report presents the second phase of a baseline mapping project conducted for the Environmental Restoration Department (ERD) at Savannah River Site. The purpose of this second phase is to map the structure and distribution of mud (clay and silt-sized sediment) within the vadose zone beneath A/M Area. The results presented in this report will assist future characterization and remediation activities in the vadose zone and upper aquifer zones in A/M Area

  13. Groundwater flow in the Venice lagoon and remediation of the Porto Marghera industrial area (Italy)

    Science.gov (United States)

    Beretta, Giovanni Pietro; Terrenghi, Jacopo

    2017-05-01

    This study aims to determine the groundwater flow in a large area of the Venice (northeast Italy) lagoon that is under great anthropogenic pressure, which is influencing the regional flow in the surficial aquifer (about 30 m depth). The area presents several elements that condition the groundwater flow: extraction by means of drainage pumps and wells; tidal fluctuation; impermeable barriers that define part of the coastline, rivers and artificial channels; precipitation; recharge, etc. All the elements were studied separately, and then they were brought together in a numerical groundwater flow model to estimate the impact of each one. Identification of the impact of each element will help to optimise the characteristics of the Porto Marghera remediation systems. Longstanding industrial activity has had a strong impact on the soil and groundwater quality, and expensive and complex emergency remediation measures in problematic locations have been undertaken to ensure the continuity of industrial and maritime activities. The land reclamation and remediation works withdraw 56-74% of the water budget, while recharge from the river accounts for about 21-48% of the input. Only 21-42% of groundwater in the modelled area is derived from natural recharge sources, untouched by human activity. The drop of the piezometric level due to the realization of the upgradient impermeable barrier can be counteracted with the reduction of the pumping rate of the remediation systems.

  14. Development of a sitewide groundwater remediation strategy at the Hanford Site, Washington

    International Nuclear Information System (INIS)

    Goswami, D.

    1996-01-01

    Over 440 km 2 (170 mi 2 ) of groundwater beneath the Hanford Site are contaminated by hazardous and radioactive waste, out of which almost half is over state and federal drinking water standards. In addition to the complicated nature of these plumes, remediation is further obscured by limited application of available technologies and hydrogeologic information. This paper briefly describes the processes used by the Washington State Department of Ecology (Ecology), U.S. Environmental Protection Agency, and U.S. Department of Energy (USDOE) in developing a sitewide groundwater remediation strategy for Hanford and its outcome. As an initial approach to sitewide groundwater remediation, the strategy is to remediate the major plumes found in the reactor areas (100 Area) adjacent to the Columbia River and contain the major plumes found in the Central Plateau region (200 Area). This approach was based mainly on the qualitative risk, stakeholder's and tribe's values, and available technical feasibility. The strategy emphasizes the use of existing treatment and extraction technology for the remediation of groundwater in combination with proposed and existing site infrastructure. This work is being performed in parallel with ongoing risk and other feasibility activities. Under this strategy, innovative technologies being developed are in the areas of dense nonaqueous phase liquid identification and recovery, and problems associated with strontium-90, cesium-137, and plutonium in the vadose zone and groundwater. The final remediation strategy alternatives remain a product of risk assessment, technical feasibility, site use scenario, and cost consideration. In order to develop a strategy for the final cleanup, several issues such as aquifer restoration, natural attenuation, potential contamination of groundwater from the tank farms and from the existing contamination source in the vadose zone must be looked in detail in conjuction with public and stakeholder's values

  15. A two-dimensional analytical model for groundwater flow in a leaky aquifer extending finite distance under the estuary

    Science.gov (United States)

    Chuang, Mo-Hsiung; Hung, Chi-Tung; -Yen Lin, Wen; Ma, Kuo-chen

    2017-04-01

    In recent years, cities and industries in the vicinity of the estuarine region have developed rapidly, resulting in a sharp increase in the population concerned. The increasing demand for human activities, agriculture irrigation, and aquaculture relies on massive pumping of water in estuarine area. Since the 1950s, numerous studies have focused on the effects of tidal fluctuations on groundwater flow in the estuarine area. Tide-induced head fluctuation in a two-dimensional estuarine aquifer system is complicated and rather important in dealing with many groundwater management or remediation problems. The conceptual model of the aquifer system considered is multi-layered with estuarine bank and the leaky aquifer extend finite distance under the estuary. The solution of the model describing the groundwater head distribution in such an estuarine aquifer system and subject to the tidal fluctuation effects from estuarine river is developed based on the method of separation of variables along with river boundary. The solutions by Sun (Sun H. A two-dimensional analytical solution of groundwater response to tidal loading in an estuary, Water Resour. Res. 1997; 33:1429-35) as well as Tang and Jiao (Tang Z. and J. J. Jiao, A two-dimensional analytical solution for groundwater flow in a leaky confined aquifer system near open tidal water, Hydrological Processes, 2001; 15: 573-585) can be shown to be special cases of the present solution. On the basis of the analytical solution, the groundwater head distribution in response to estuarine boundary is examined and the influences of leakage, hydraulic parameters, and loading effect on the groundwater head fluctuation due to tide are investigated and discussed. KEYWORDS: analytical model, estuarine river, groundwater fluctuation, leaky aquifer.

  16. Aquifer response to earth tides

    International Nuclear Information System (INIS)

    Kanehiro, B.Y.; Narasimhan, T.N.

    1981-01-01

    The relation presented in the first part of this paper are applicable to packed-off wells and other situations where appreciable flow to the well does not exist. Comparisons of aquifer properties determined from the response to earth tides and from the more standard pumping tests for the two California fields are reasonably good. The case of an open well makes the problem more complicated, since there may be an appreciable amount of flow to the well. This flow to the well is seen as either a phase lag or as a difference in the ratio of the well signal to the tide for the semidiurnal and diurnal components of the tide. The latter is probably the better and more accurate indicator of flow to the well. Analyses of such situations, however, become involved and are probably best done as case-by-case studies. The numerical solutions show that treating the inverse problem through numerical modeling is at least feasible for any individual situation. It may be possible to simplify the inverse problem through the generation of type curves, but general type curves that are applicable to diverse situations are not likely to be practical. 7 figures

  17. New IAEA guidelines on environmental remediation

    Energy Technology Data Exchange (ETDEWEB)

    Fesenko, Sergey [International Atomic Energy Agency, A2444, Seibersdorf (Austria); Howard, Brenda [Centre for Ecology and Hydrology, Lancaster Environment Centre, LA1 4AP, Lancaster (United Kingdom); Kashparov, Valery [Ukrainian Institute of Agricultural Radiology, 08162, 7, Mashinobudivnykiv str., Chabany, Kyivo-Svyatoshin region, Kyiv (Ukraine); Sanzharova, Natalie [Russian Institute of Agricultural Radiology and Agroecology, Russian Federation, 249032, Obninsk (Russian Federation); Vidal, Miquel [Analytical Chemistry Department-Universitat de Barcelona, Barcelona, 08028 Barcelona (Spain)

    2014-07-01

    In response to the needs of its Member States, the International Atomic Energy Agency (IAEA) has published many documents covering different aspects of remediation of contaminated environments. These documents range from safety fundamentals and safety requirements to technical documents describing remedial technologies. Almost all the documents on environmental remediation are related to uranium mining areas and decommissioning of nuclear facilities. IAEA radiation safety standards on remediation of contaminated environments are largely based on these two types of remediation. The exception is a document related to accidents, namely the IAEA TRS No. 363 'Guidelines for Agricultural Countermeasures Following an Accidental Release of Radionuclides'. Since the publication of TRS 363, there has been a considerable increase in relevant information. In response, the IAEA initiated the development of a new document, which incorporated new knowledge obtained during last 20 years, lessons learned and subsequent changes in the regulatory framework. The new document covers all aspects related to the environmental remediation from site characterisation to a description of individual remedial actions and decision making frameworks, covering urban, agricultural, forest and freshwater environments. Decisions taken to commence remediation need to be based on an accurate assessment of the amount and extent of contamination in relevant environmental compartments and how they vary with time. Major aspects of site characterisation intended for remediation are described together with recommendations on effective sampling programmes and data compilation for decision making. Approaches for evaluation of remedial actions are given in the document alongside the factors and processes which affect their implementation for different environments. Lessons learned following severe radiation accidents indicate that remediation should be considered with respect to many different

  18. Radial Dupuit interface flow to assess the aquifer storage and recovery potential of saltwater aquifers

    NARCIS (Netherlands)

    Bakker, M.

    2009-01-01

    A new accurate numerical solution is presented for aquifer storage and recovery (ASR) systems in coastal aquifers; flow is approximated as radial Dupuit interface flow. The radial velocities of points on the interface are a function of time, the vertical coordinate, and the dimensionless parameter D

  19. Aquifer pre-oxidation using permanganate to mitigate water quality deterioration during aquifer storage recovery

    NARCIS (Netherlands)

    Antoniou, E.A.; Hartog, N.; van Breukelen, B.M.; Stuijfzand, P.J.

    2014-01-01

    Water quality deterioration is a common occurrence that may limit the recovery of injected water during aquifer storage and recovery (ASR) operations. This limitation is often induced by the oxidation of the reduced aquifer components by the oxygenated injection water. This study explores the

  20. Guarani aquifer hydrogeological synthesis of the Guarani aquifer system. Edicion bilingue

    International Nuclear Information System (INIS)

    2009-01-01

    This work represents the synthesis of current knowledge of the Guarani Aquifer System, based on technical products made by different companies and consultants who participated in the framework of the Project for Environmental Protection and Sustainable Development of the Guarani Aquifer.

  1. Aquifer characterization through an integrated GIS-based tool

    Science.gov (United States)

    Criollo, Rotman; Velasco, Violeta; Vázquez-Suñé, Enric; Serrano-Juan, Alejandro; Alcaraz, Mar; García-Gil, Alejandro

    2016-04-01

    Hydraulic parameters of the subsurface (transmissivity, hydraulic conductivity, storativity and specific storage) are important to achieve hydrogeological studies such as environmental impact assessments, water resources evaluations or groundwater contamination remediation, among others. There are several methods to determine aquifer parameters but pumping test is the most commonly used method to obtain them and generally leads to reliable hydraulic parameters. These parameters and other hydraulic data available for integration into the hydrogeological studies (which currently are supported by groundwater numerical models) usually has a very diverse origin and format and, therefore, a chance of bias in the interpretations. Consequently, it becomes necessary to have effective instruments that facilitate the pre-process, the visualization, the analysis and the validation (e.g. graphical analysis techniques) of this great amount of data. To achieve this in a clear and understandable manner, the GIS environment is a useful instrument. We developed a software to analyze pumping tests in a GIS platform environment to support the hydraulic parameterization of groundwater flow and transport models. This novel platform provides a package of tools for collecting, managing, analyzing, processing and interpreting data derived from pumping tests in a GIS environment. Additionally, within the GIS platform, it is possible to process the hydraulic parameters obtained from the pumping test and to create spatial distribution maps, perform geostatistical analysis and export the information to an external software platform. These tools have been applied in the metropolitan area of Barcelona (Spain) to tests out and improve their usefulness in hydrogeological analysis.

  2. Aquifer Storage Recovery (ASR) of chlorinated municipal drinking water in a confined aquifer

    Science.gov (United States)

    Izbicki, John A.; Petersen, Christen E.; Glotzbach, Kenneth J.; Metzger, Loren F.; Christensen, Allen H.; Smith, Gregory A.; O'Leary, David R.; Fram, Miranda S.; Joseph, Trevor; Shannon, Heather

    2010-01-01

    About 1.02 x 106 m3 of chlorinated municipal drinking water was injected into a confined aquifer, 94-137 m below Roseville, California, between December 2005 and April 2006. The water was stored in the aquifer for 438 days, and 2.64 x 106 m3 of water were extracted between July 2007 and February 2008. On the basis of Cl data, 35% of the injected water was recovered and 65% of the injected water and associated disinfection by-products (DBPs) remained in the aquifer at the end of extraction. About 46.3 kg of total trihalomethanes (TTHM) entered the aquifer with the injected water and 37.6 kg of TTHM were extracted. As much as 44 kg of TTHMs remained in the aquifer at the end of extraction because of incomplete recovery of injected water and formation of THMs within the aquifer by reactions with freechlorine in the injected water. Well-bore velocity log data collected from the Aquifer Storage Recovery (ASR) well show as much as 60% of the injected water entered the aquifer through a 9 m thick, high-permeability layer within the confined aquifer near the top of the screened interval. Model simulations of ground-water flow near the ASR well indicate that (1) aquifer heterogeneity allowed injected water to move rapidly through the aquifer to nearby monitoring wells, (2) aquifer heterogeneity caused injected water to move further than expected assuming uniform aquifer properties, and (3) physical clogging of high-permeability layers is the probable cause for the observed change in the distribution of borehole flow. Aquifer heterogeneity also enhanced mixing of native anoxic ground water with oxic injected water, promoting removal of THMs primarily through sorption. A 3 to 4-fold reduction in TTHM concentrations was observed in the furthest monitoring well 427 m downgradient from the ASR well, and similar magnitude reductions were observed in depth-dependent water samples collected from the upper part of the screened interval in the ASR well near the end of the extraction

  3. Status report: Fernald site remediation

    International Nuclear Information System (INIS)

    Craig, J.R. Jr.; Saric, J.A.; Schneider, T.; Yates, M.K.

    1995-01-01

    The Fernald site is rapidly transitioning from a Remedial Investigation/ Feasibility Study (RI/FS) site to one where design and construction of the remedies dominates. Fernald is one of the first sites in the Department of Energy (DOE) complex to accomplish this task and real physical progress is being made in moving the five operable units through the CERCLA process. Two of the required Records of Decision (ROD) are in hand and all five operable units will have received their RODs (IROD for OU3) by the end of 1995. Pre-design investigations, design work or construction are now in progress on the operable units. The lessons learned from the work done to date include implementing innovations in the RI and FS process as well as effective use of Removal Actions to begin the actual site remediation. Also, forging close working relationships with the Federal and State Regulators, citizens action groups and the Fernald Citizens Task Force has helped move the program forward. The Fernald successes have been achieved by close coordination and cooperation among all groups working on the projects and by application of innovative technologies within the decision making process

  4. Strategic planning for remediation projects

    International Nuclear Information System (INIS)

    Tapp, J.W.

    1995-01-01

    Remediation projects may range from a single leaking storage tank to an entire plant complex or producing oil and gas field. Strategic planning comes into play when the contamination of soil and groundwater is extensive. If adjacent landowners have been impacted or the community at large is concerned about the quality of drinking water, then strategic planning is even more important. (1) To manage highly complex interrelated issues--for example, the efforts expended on community relations can alter public opinion, which can impact regulatory agency decisions that affect cleanup standards, which can...and so on. (2) To ensure that all potential liabilities are managed--for example, preparation for the defense of future lawsuits is essential during site investigation and remediation. (3) To communicate with senior management--when the remediation team provides a strategic plan that includes both technical and business issues, senior management has the opportunity to become more involved and make sound policy decisions. The following discusses the elements of a strategic plan, who should participate in it, and the issues that should be considered

  5. Stochastic analysis of virus transport in aquifers

    Science.gov (United States)

    Campbell Rehmann, Linda L.; Welty, Claire; Harvey, Ronald W.

    1999-01-01

    A large-scale model of virus transport in aquifers is derived using spectral perturbation analysis. The effects of spatial variability in aquifer hydraulic conductivity and virus transport (attachment, detachment, and inactivation) parameters on large-scale virus transport are evaluated. A stochastic mean model of virus transport is developed by linking a simple system of local-scale free-virus transport and attached-virus conservation equations from the current literature with a random-field representation of aquifer and virus transport properties. The resultant mean equations for free and attached viruses are found to differ considerably from the local-scale equations on which they are based and include effects such as a free-virus effective velocity that is a function of aquifer heterogeneity as well as virus transport parameters. Stochastic mean free-virus breakthrough curves are compared with local model output in order to observe the effects of spatial variability on mean one-dimensional virus transport in three-dimensionally heterogeneous porous media. Significant findings from this theoretical analysis include the following: (1) Stochastic model breakthrough occurs earlier than local model breakthrough, and this effect is most pronounced for the least conductive aquifers studied. (2) A high degree of aquifer heterogeneity can lead to virus breakthrough actually preceding that of a conservative tracer. (3) As the mean hydraulic conductivity is increased, the mean model shows less sensitivity to the variance of the natural-logarithm hydraulic conductivity and mean virus diameter. (4) Incorporation of a heterogeneous colloid filtration term results in higher predicted concentrations than a simple first-order adsorption term for a given mean attachment rate. (5) Incorporation of aquifer heterogeneity leads to a greater range of virus diameters for which significant breakthrough occurs. (6) The mean model is more sensitive to the inactivation rate of viruses

  6. Hydrological connectivity of perched aquifers and regional aquifers in semi-arid environments: a case study from Namibia

    Science.gov (United States)

    Hamutoko, J. T.; Wanke, H.

    2017-12-01

    Integrated isotopic and hydrological tracers along with standard hydrological data are used to understand complex dry land hydrological processes on different spatial and temporal scales. The objective of this study is to analyse the relationship between the perched aquifers and the regional aquifer using hydrochemical data and isotopic composition in the Cuvelai-Etosha Basin in Namibia. This relation between the aquifers will aid in understanding groundwater recharge processes and flow dynamics. Perched aquifers are discontinuous shallow aquifers with water level ranging from 0 to 30 meters below ground level. The regional aquifer occurs in semi-consolidated sandstone at depths between about 60 and 160 meters below ground level. Water samples were collected from both aquifers in 10 villages and were analysed for major ions and stable isotopes. The results show overlapping hydrochemistry and isotopic compositions of both aquifers in 8 villages which suggest the possibility of perched aquifer water infiltrating into the regional aquifer. In two villages the hydrochemistry and isotopic composition of the aquifers are totally different and this suggests that there is no interaction between this aquifers. Areas where perched aquifers are connected to regional aquifers maybe recharge zones. These finding have important implications for groundwater resource management.

  7. Salmon Site Remedial Investigation Report

    International Nuclear Information System (INIS)

    1999-01-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  8. Use of Geophysical and Remote Sensing Data for Assessment of Aquifer Depletion and Related Land Deformation

    Science.gov (United States)

    Othman, Abdullah; Sultan, Mohamed; Becker, Richard; Alsefry, Saleh; Alharbi, Talal; Gebremichael, Esayas; Alharbi, Hassan; Abdelmohsen, Karem

    2018-01-01

    An integrated approach [field, Interferometric Synthetic Aperture Radar (InSAR), hydrogeology, geodesy, and spatial analysis] was adopted to identify the nature, intensity, and spatial distribution of deformational features (sinkholes, fissures, differential settling) reported over fossil aquifers in arid lands, their controlling factors, and possible remedies. The Lower Mega Aquifer System (area 2 × 106 km2) in central and northern Arabia was used as a test site. Findings suggest that excessive groundwater extraction from the fossil aquifer is the main cause of deformation: (1) deformational features correlated spatially and/or temporally with increased agricultural development and groundwater extraction, and with a decline in water levels and groundwater storage (- 3.7 ± 0.6 km3/year); (2) earthquake events (years 1985-2016; magnitude 1-5) are largely (65% of reported earthquakes) shallow (1-5 km) and increased from 1 event/year in the early 1980s (extraction 1 km3/year), up to 13 events/year in the 1990s (average annual extraction > 6.4 km3). Results indicate that faults played a role in localizing deformation given that deformational sites and InSAR-based high subsidence rates (- 4 to - 15 mm/year) were largely found within, but not outside of, NW-SE-trending grabens bound by the Kahf fault system. Findings from the analysis of Gravity Recovery and Climate Experiment solutions indicate that sustainable extraction could be attained if groundwater extraction was reduced by 3.5-4 km3/year. This study provides replicable and cost-effective methodologies for optimum utilization of fossil aquifers and for minimizing deformation associated with their use.

  9. Identifying functional zones of denitrification in heterogeneous aquifer systems by numerical simulations - a case study

    Science.gov (United States)

    Jang, E.; Kalbacher, T.; He, W.; Shao, H.; Schueth, C.; Kolditz, O.

    2014-12-01

    Nitrate contamination in shallow groundwater is still one of the common problems in many countries. Because of its high solubility and anionic nature, nitrate can easily leach through soil and persist in groundwater for decades. High nitrate concentration has been suggested as a major cause of accelerated eutrophication, methemoglobinemia and gastric cancer. There are several factors influencing the fate of nitrate in groundwater system, which is e.g. distribution of N- sources to soil and groundwater, distribution and amount of reactive substances maintaining denitrification, rate of nitrate degradation and its kinetics, and geological characteristics of the aquifer. Nitrate transport and redox transformation processes are closely linked to complex and spatially distributed physical and chemical interaction, therefore it is difficult to predict and quantify in the field and laboratory experiment. Models can play a key role in elucidation of nitrate reduction pathway in groundwater system and in the design and evaluation of field tests to investigate in situ remediation technologies as well. The goal of the current study is to predict groundwater vulnerability to nitrate, to identify functional zones of denitrification in heterogeneous aquifer systems and to describe the uncertainty of the predictions due to scale effects. For this aim, we developed a kinetic model using multi-component mass transport code OpenGeoSys coupling with IPhreeqc module of the geochemical solver PHREEQC. The developed model included sequential aerobic and nitrate-based respiration, multi-Monod kinetics, multi-species biogeochemical reactions, and geological characteristics of the groundwater aquifer. Moreover water-rock interaction such as secondary mineral precipitation was also included in this model. In this presentation, we focused on the general modelling approach and present the simulation results of nitrate transport simulation in a hypothetical aquifer systems based on data from

  10. Coal Bed Aquifer Tests: a Case Study

    Science.gov (United States)

    Weeks, E. P.

    2005-12-01

    Coal bed methane development is proceeding at a rapid pace in the USA and in several other countries. Development of coal bed methane requires the simultaneous co-production of water in a manner that maximizes the amount of drawdown while minimizing the amount of water pumped. Determination of optimal well spacing and production rates to achieve such drawdowns requires knowledge of the hydraulic properties of the coal aquifer. Natural closely spaced fractures, termed cleats, develop during coal formation as an orthogonal fracture network that creates anisotropic transmissivity. Water held in the matrix porosity of the coal is released slowly to the cleat system during pumping, resulting in coal beds behaving as dual-porosity aquifers. Knowledge of the magnitude and orientation of the principal axes of the transmissivity tensor, as well as of the late-time dual-porosity storage coefficient, are needed to optimally design well fields for the exploitation of coal bed methane. An aquifer test with three observation wells was conducted to determine these properties for a 7.6- m thick coal bed located in the Powder River Basin, southeast Montana. The test results exhibit all the features that would be expected for a test on an anisotropic dual-porosity medium. However, the test was initially misinterpreted, providing a cautionary tale. The initial interpretation assumed a single-porosity aquifer, and the late-time break in slope was assumed to represent the effects of a hidden boundary. Despite their apparent plausibility, the results of the analysis raised several red flags. An attempt to determine the location of the hidden boundary failed, the indicated specific storage was implausibly small, and the analysis of recovery data provided transmissivity values that were in disagreement with those determined from the drawdown analysis. Reanalysis of the test using type curves developed for a dual-porosity aquifer resulted in a transmissivity value that is about 25% smaller

  11. Effects of unsaturated zone on aquifer test analysis in a shallow-aquifer system

    Science.gov (United States)

    Halford, K.J.

    1997-01-01

    A comparison between two hypothetical flow models of an unconfined aquifer, one saturated and the other variably saturated, indicates that the variably saturated model which explicitly models drainage from the unsaturated zone provides a better conceptual framework for analyzing unconfined aquifer test data and better estimates of the lateral and vertical hydraulic conductivity in fine-grained sands. Explicitly accounting for multiple aquifers, well-bore storage, and the effects of delayed drainage from the unsaturated zone increases confidence in aquifer property estimates by removing some assumptions and allowing for the inclusion of early time data and water-table observations in an aquifer test analysis. The inclusion of the unsaturated zone expands the number of parameters to be estimated, but reasonable estimates of lateral and vertical hydraulic conductivity and specific storage of the unconfined aquifer can be obtained. For the cases examined, only the van Genuchten parameter ?? needed to be determined by the test, because the parameters n and ??(r) had a minimal effect on the estimates of hydraulic conductivities, and literature values could be used for these parameters. Estimates of lateral and vertical hydraulic conductivity using MODFLOW were not as good as the VS2DT based estimates and differed from the known values by as much as 30 percent. The hydraulic properties of a surficial aquifer system were estimated through a series of aquifer tests conducted at Cecil Field Naval Air Station in Jacksonville, Florida. Aquifer test results were analyzed by calibrating a variably saturated, radial flow model to the measured drawdowns. Parameter estimation was performed by minimizing the difference between simulated and measured drawdowns with an optimization routine coupled to VS2DT and was constrained by assuming that the hydraulic properties of each aquifer or confining unit were homogeneous. Given the hydrogeologic conditions at the field site, estimating

  12. Bioremediation of Benzene-contaminated Underground Aquifers

    Science.gov (United States)

    Watanabe, Kazuya; Takahata, Yoh

    Contamination of underground aquifers with gasoline occurs frequently. Among the gasoline constituents, benzene is of great environmental concern, since it is carcinogenic, water-soluble and persistent under anaerobic conditions. We have analyzed a gasoline-contaminated underground aquifer undergoing natural attenuation, where benzene was degraded, albeit slowly, under anaerobic conditions. RNA-based stable-isotope probing identified that bacteria affiliated with the genus AZOARCUS was responsible for benzene degradation under nitrate-reducing conditions. This result was confirmed by isolating an anaerobic benzene-degrading bacterium AZOARCUS sp. strain DN11. This strain degraded benzene at relatively low concentrations (as low as 10 ppb). It could also degrade toluene and xylenes. In laboratory bioaugmentation experiments using benzene-contaminated groundwater, it was demonstrated that supplementation with DN11 significantly accelerated benzene degradation under a nitrate-reducing condition. These results indicate that DN11 is potentially useful for degrading benzene that contaminates underground aquifers at relatively low concentrations.

  13. Ground Water movement in crystalline rock aquifers

    International Nuclear Information System (INIS)

    Serejo, A.N.C.; Freire, C.; Siqueira, H.B. de; Frischkorn, H.; Torquato, J.R.F.; Santiago, M.M.F.; Barbosa, P.C.

    1984-01-01

    Ground water movement studies were performed in crystalline rock aquifers from the upper Acarau River hydrographic basin, state of Ceara, Brazil. The studies included carbon-14, 18 O/ 16 O and tritium measurements as well as chemical analysis. A total of 35 wells were surveyed during drought seasons. Carbon-14 values displayed little variation which implied that the water use was adequate despite of the slower recharge conditions. Fairly constant isotopic 18 O/ 16 O ratio values in the wells and their similarity with rainwater values indicated that the recharge is done exclusively by pluvial waters. A decreasing tendency within the tritium concentration values were interpreted as a periodic rainwater renewal for these aquifers. The chemical analysis demonstrated that there is in fact no correlation between salinity and the time the water remains in the aquifer itself. (D.J.M.) [pt

  14. Aquifer thermal energy storage. International symposium: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    Aquifers have been used to store large quantities of thermal energy to supply process cooling, space cooling, space heating, and ventilation air preheating, and can be used with or without heat pumps. Aquifers are used as energy sinks and sources when supply and demand for energy do not coincide. Aquifer thermal energy storage may be used on a short-term or long-term basis; as the sole source of energy or as a partial storage; at a temperature useful for direct application or needing upgrade. The sources of energy used for aquifer storage are ambient air, usually cold winter air; waste or by-product energy; and renewable energy such as solar. The present technical, financial and environmental status of ATES is promising. Numerous projects are operating and under development in several countries. These projects are listed and results from Canada and elsewhere are used to illustrate the present status of ATES. Technical obstacles have been addressed and have largely been overcome. Cold storage in aquifers can be seen as a standard design option in the near future as it presently is in some countries. The cost-effectiveness of aquifer thermal energy storage is based on the capital cost avoidance of conventional chilling equipment and energy savings. ATES is one of many developments in energy efficient building technology and its success depends on relating it to important building market and environmental trends. This paper attempts to provide guidance for the future implementation of ATES. Individual projects have been processed separately for entry onto the Department of Energy databases.

  15. Innovative approaches to remediation for VOC sites using recirculating wells

    International Nuclear Information System (INIS)

    Dawson, G.W.

    1996-01-01

    In-well air stripping with approaches such as the patented NoVOCs system offer both cost and operational advantages over pump and treat, and in situ air sparging technologies. With in-well stripping, the water is treated in the well and discharged without being brought to the surface. Discharged water is circulated through the saturated zone acting as a carrier to continually flush contaminants from the aquifer matrix and transport them to the well for treatment. With pumping rates up to four times those of comparable extraction wells, large radii of influence can be maintained and remediation is achieved faster and more efficiently. In-well stripping is applicable to any strippable contaminant including chlorinated solvents (i.e., TCE and PCE) and hydrocarbons such as the aromatic components in petroleum fuels. Growing costs associated with water discharge, NPDES permits, water rights and, in some areas, salt water intrusion have provided economic incentives to retrofit existing pump and treat systems with NoVOCs units. A large number of wells are amenable to retrofitting depending on their diameter, location and length of screens, and back fill. Even with the new initiatives for intrinsic remediation for petroleum fuel releases, there is a role for the NoVOCs technology. Free product removal wells based on the NoVOCs design eliminate the need to treat and permit water discharges produced when generating a cone of depression for collecting the floating fuel. Additionally, the stripping action and introduction of dissolved oxygen reduce soluble hydrocarbon concentrations to risk levels that can be easily addressed through intrinsic bioremediation

  16. Tank Waste Remediation System Guide

    International Nuclear Information System (INIS)

    Robershotte, M.A.; Dirks, L.L.; Seaver, D.A.; Bothers, A.J.; Madden, M.S.

    1995-06-01

    The scope, number and complexity of Tank Waste Remediation System (TWRS) decisions require an integrated, consistent, and logical approach to decision making. TWRS has adopted a seven-step decision process applicable to all decisions. Not all decisions, however, require the same degree of rigor/detail. The decision impact will dictate the appropriate required detail. In the entire process, values, both from the public as well as from the decision makers, play a key role. This document concludes with a general discussion of the implementation process that includes the roles of concerned parties

  17. Horizontal wells in subsurface remediation

    International Nuclear Information System (INIS)

    Losonsky, G.; Beljin, M.S.

    1992-01-01

    This paper reports on horizontal wells which offer an effective alternative to vertical wells in various environmental remediation technologies. Hydrogeological advantages of horizontal wells over vertical wells include a larger zone of influence, greater screen length, higher specific capacity and lower groundwater screen entrance velocity. Because of these advantages, horizontal wells can reduce treatment time and costs of groundwater recovery (pump-and-treat), in situ groundwater aeration (sparging) and soil gas extraction (vacuum extraction). Horizontal wells are also more effective than vertical wells in landfill leachate collection (under-drains), bioremediation, and horizontal grout injection

  18. Coastal hypoxia responses to remediation

    Science.gov (United States)

    Kemp, W. M.; Testa, J. M.; Conley, D. J.; Gilbert, D.; Hagy, J. D.

    2009-07-01

    The incidence and intensity of hypoxic waters in coastal aquatic ecosystems has been expanding in recent decades coincident with eutrophication of the coastal zone. Because of the negative effects hypoxia has on many organisms, extensive efforts have been made to reduce the size and duration of hypoxia in many coastal waters. Although it has been broadly assumed that reductions in nutrient loading rates would reverse eutrophication and consequently, hypoxia, recent analyses of historical data from European and North American coastal systems suggest little evidence for simple linear response trajectories. We review existing data, analyses, and models that relate variations in the extent and intensity of hypoxia to changes in loading rates for inorganic nutrients and labile organic matter. We also assess existing knowledge of physical and ecological factors regulating oxygen in coastal marine waters and examine a broad range of examples where hypoxia responses to reductions in nutrient (or organic matter) inputs have been documented. Of the 22 systems identified where concurrent time series of loading and O2 were available, half displayed relatively clear and direct recoveries following remediation. We explored in detail 5 well-studied systems that have exhibited complex, non-linear responses to loading, including apparent "regime shifts." A summary of these analyses suggests that O2 conditions improved rapidly and linearly in systems where remediation focused on organic inputs from sewage plants, which were the primary drivers of hypoxia. In larger more open systems where diffuse nutrient loads are more important in fueling O2 depletion and where climatic influences are pronounced, responses to remediation tend to follow non-linear trends that may include hysteresis and time-lags. Improved understanding of hypoxia remediation requires that future studies use comparative approaches and consider multiple regulating factors including: (1) the dominant temporal scales

  19. Green PCB Remediation from Sediment Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — An ongoing problem facing the global environmental community including NASA centers is the removal and remediation of polychlorinated biphenyls (PCBs). PCBs were...

  20. Nuclear facility decommissioning and site remedial actions

    Energy Technology Data Exchange (ETDEWEB)

    Knox, N.P.; Webb, J.R.; Ferguson, S.D.; Goins, L.F.; Owen, P.T.

    1990-09-01

    The 394 abstracted references on environmental restoration, nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the eleventh in a series of reports prepared annually for the US Department of Energy's Remedial Action Programs. Citations to foreign and domestic literature of all types -- technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions -- have been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy's Remedial Action Programs. Major sections are (1) Surplus Facilities Management Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Programs, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Grand Junction Remedial Action Program, (7) Uranium Mill Tailings Management, (8) Technical Measurements Center, (9) Remedial Action Program, and (10) Environmental Restoration Program. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication title. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, subject category, and keywords. This report is a product of the Remedial Action Program Information Center (RAPIC), which selects and analyzes information on remedial actions and relevant radioactive waste management technologies.

  1. Nuclear facility decommissioning and site remedial actions

    International Nuclear Information System (INIS)

    Knox, N.P.; Webb, J.R.; Ferguson, S.D.; Goins, L.F.; Owen, P.T.

    1990-09-01

    The 394 abstracted references on environmental restoration, nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the eleventh in a series of reports prepared annually for the US Department of Energy's Remedial Action Programs. Citations to foreign and domestic literature of all types -- technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions -- have been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy's Remedial Action Programs. Major sections are (1) Surplus Facilities Management Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Programs, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Grand Junction Remedial Action Program, (7) Uranium Mill Tailings Management, (8) Technical Measurements Center, (9) Remedial Action Program, and (10) Environmental Restoration Program. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication title. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, subject category, and keywords. This report is a product of the Remedial Action Program Information Center (RAPIC), which selects and analyzes information on remedial actions and relevant radioactive waste management technologies

  2. Assessing sustainable remediation frameworks using sustainability principles.

    Science.gov (United States)

    Ridsdale, D Reanne; Noble, Bram F

    2016-12-15

    The remediation industry has grown exponentially in recent decades. International organizations of practitioners and remediation experts have developed several frameworks for integrating sustainability into remediation projects; however, there has been limited attention to how sustainability is approached and operationalized in sustainable remediation frameworks and practices - or whether sustainability plays any meaningful role at all in sustainable remediation. This paper examines how sustainability is represented in remediation frameworks and the guidance provided for practical application. Seven broad sustainability principles and review criteria are proposed and applied to a sample of six international remediation frameworks. Not all review criteria were equally satisfied and none of the frameworks fully met all criteria; however, the best performing frameworks were those identified as sustainability remediation frameworks. Intra-generational equity was addressed by all frameworks. Integrating social, economic and biophysical components beyond triple-bottom-line indicators was explicitly addressed only by the sustainable remediation frameworks. No frameworks provided principle- or rule-based guidance for dealing with trade-offs in sustainability decisions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Modelling contaminant transport in saturated aquifers

    International Nuclear Information System (INIS)

    Lakshminarayana, V.; Nayak, T.R.

    1990-01-01

    With the increase in population and industrialization the problem of pollution of groundwater has become critical. The present study deals with modelling of pollutant transport through saturated aquifers. Using this model it is possible to predict the concentration distribution, spatial as well as temporal, in the aquifer. The paper also deals with one of the methods of controlling the pollutant movement, namely by pumping wells. A simulation model is developed to determine the number, location and rate of pumping of a number of wells near the source of pollution so that the concentration is within acceptable limits at the point of interest. (Author) (18 refs., 14 figs., tab.)

  4. EPA Region 6 Sole Source Aquifers in Louisiana, Geographic NAD83, EPA (1996) [sole_source_aquifers_LA_EPA_1996

    Data.gov (United States)

    Louisiana Geographic Information Center — Polygon layer of EPA Region 6 sole source aquifers in Louisiana. The sole source aquifers represented are Chicot and Southern Hills in Louisiana/Mississippi.

  5. Comparison of groundwater flow in Southern California coastal aquifers

    Science.gov (United States)

    Hanson, Randall T.; Izbicki, John A.; Reichard, Eric G.; Edwards, Brian D.; Land, Michael; Martin, Peter

    2009-01-01

    Development of the coastal aquifer systems of Southern California has resulted in overdraft, changes in streamflow, seawater intrusion, land subsidence, increased vertical flow between aquifers, and a redirection of regional flow toward pumping centers. These water-management challenges can be more effectively addressed by incorporating new understanding of the geologic, hydrologic, and geochemical setting of these aquifers.

  6. Hydrodynamic characterization of the Paleocene aquifer in the ...

    African Journals Online (AJOL)

    The intense exploitation of shallow aquifers in the coastal basin of Togo provokes a rapid depletion of these reservoirs. The confined paleocene aquifer represents potential reserves that are yet little exploited. This paper presents the hydrodynamic characterization of this aquifer. Piezometric data established from 80 wells ...

  7. Some Similarities and Differences Between Compositions Written by Remedial and Non-Remedial College Freshmen.

    Science.gov (United States)

    House, Elizabeth B.; House, William J.

    The essays composed by 84 remedial and 77 nonremedial college freshmen were analyzed for some features proposed by Mina Shaughnessy as being characteristic of basic writers. The students were enrolled in either a beginning remedial class (098), a class at the next level of remediation (099), or a regular English class (101). The essays were…

  8. DECHEM: A remedial planning tool for metallic contaminants in soil at UMTRA Project sites

    International Nuclear Information System (INIS)

    1989-03-01

    The DECHEM (DEcontamination of CHEMicals) method was developed for the Uranium Mill Tailings Remedial Action (UMTRA) Project to guide characterization and remedial planning for metals contamination in soils. This is necessary because non-radiological hazardous constituents may be more mobile than radium-226 (Ra-226), and hence may migrate more deeply into subpile soils (beneath tailings that are to be relocated) or into adjacent contaminated soils at UMTRA Project sites. The result is that remedial action to the Ra-226 excavation limit, as specified in the US Environmental Protection Agency (EPA) standards, may not adequately remove hazardous non-radiological contamination. Unmitigated, these contaminants in soil may cause health risks because of their presence in resuspended particles, their uptake by crops or fodder their seepage into aquifers used for drinking water or other possible exposure pathways. The DECHEM method was developed in response to the need for advanced planning for the remediation of chemical contaminants at UMTRA Project sites, and includes the following elements: Establishment of acceptable exposure rates for humans to chemicals, based on EPA guidelines or other toxicological literature. Modeling of chemical migration through environmental pathways from a remediated UMTRA Project site to humans. Determination of allowable residual concentrations (i.e., cleanup guidelines) for chemicals in soils that results in doses to humans that are below established acceptable exposure rates. The initial development and application of the DECHEM method has focused upon hazardous metallic contaminants such as arsenic, lead, molybdenum, and selenium, which are known to occur in elevated concentrations at some UMTRA Project sites

  9. Aquifer geochemistry at potential aquifer storage and recovery sites in coastal plain aquifers in the New York city area, USA

    Science.gov (United States)

    Brown, C.J.; Misut, P.E.

    2010-01-01

    The effects of injecting oxic water from the New York city (NYC) drinking-water supply and distribution system into a nearby anoxic coastal plain aquifer for later recovery during periods of water shortage (aquifer storage and recovery, or ASR) were simulated by a 3-dimensional, reactive-solute transport model. The Cretaceous aquifer system in the NYC area of New York and New Jersey, USA contains pyrite, goethite, locally occurring siderite, lignite, and locally varying amounts of dissolved Fe and salinity. Sediment from cores drilled on Staten Island and western Long Island had high extractable concentrations of Fe, Mn, and acid volatile sulfides (AVS) plus chromium-reducible sulfides (CRS) and low concentrations of As, Pb, Cd, Cr, Cu and U. Similarly, water samples from the Lloyd aquifer (Cretaceous) in western Long Island generally contained high concentrations of Fe and Mn and low concentrations of other trace elements such as As, Pb, Cd, Cr, Cu and U, all of which were below US Environmental Protection Agency (USEPA) and NY maximum contaminant levels (MCLs). In such aquifer settings, ASR operations can be complicated by the oxidative dissolution of pyrite, low pH, and high concentrations of dissolved Fe in extracted water.The simulated injection of buffered, oxic city water into a hypothetical ASR well increased the hydraulic head at the well, displaced the ambient groundwater, and formed a spheroid of injected water with lower concentrations of Fe, Mn and major ions in water surrounding the ASR well, than in ambient water. Both the dissolved O2 concentrations and the pH of water near the well generally increased in magnitude during the simulated 5-a injection phase. The resultant oxidation of Fe2+ and attendant precipitation of goethite during injection provided a substrate for sorption of dissolved Fe during the 8-a extraction phase. The baseline scenario with a low (0.001M) concentration of pyrite in aquifer sediments, indicated that nearly 190% more water

  10. Solar One demolition and remediation

    International Nuclear Information System (INIS)

    Wallace, G.L.

    1995-01-01

    Solar One was designed to demonstrate the feasibility of generating electrical energy from solar power using a central receiver concept. An array of heliostats focused sunlight onto a central receiver, which superheated water to produce steam. Although Solar One was successful, the oil-based Thermal Storage System (TSS), used to store heat energy for power generation at night, was not efficient. When the TSS was demolished for the installation of a more efficient molten salt system, a major effort was made to salvage or recycle all of its equipment and materials. During TSS demolition, approximately 7 tons of aluminum shielding and 205 tons of steel were salvaged as scrap metal; 200 tons of concrete was used for erosion protection along the Mohave River banks; 150,000 gallons of oil was recycled and 100 tons of equipment was salvaged for use at other facilities. During remediation, approximately 9,000 tons of oil contaminated sand, gravel and soil was recycled into approximately 10,000 tons of asphalt concrete and used to pave a nearby 5-acre parking lot at Barstow College. This not only reduced project remediation costs, but also met environmental requirements and provided a much needed community service. Of the estimated 11,864 tons of equipment and material from the TSS, less than 1% was disposed of at a landfill

  11. Electrokinetic remediation of contaminated soils

    International Nuclear Information System (INIS)

    Lindgren, E.R.; Kozak, M.W.; Mattson, E.D.

    1991-01-01

    Electrokinetic remediation of contaminated soil has been demonstrated for saturated and unsaturated sand in preliminary experiments using a novel transport visualization technique. Large anionic organic dyes were mixed with a portion of soil and the rate of electromigration of the dye in an imposed electric field was monitored photographically. One of the fastest current-normalized electromigration rates was measured in the driest sand, which contained 7% water by weight. This moisture content is typical of the moisture content in the unsaturated zone of subsurface native soils found in New Mexico. The characteristics of the electromigration were similar in both the saturated and unsaturated sand. The leading edge of the dye migration front was diffuse while the trailing edge was sharp and concentrated. This and other observed behavior may indicate a concentration effect, where the electromigration rate of dilute dye is greater than that of concentrated dye. The soil left after the trailing edge passed seemed to contain no residual dye in both the saturated and unsaturated cases. The success of demonstrating electromigration of large molecules in unsaturated soil is encouraging and indicates that it may be feasible to remediate in situ anionic heavy metals such as chromate from unsaturated soil with electrokinetic techniques. 23 refs., 7 figs

  12. Characterization technologies for environmental remediation

    Energy Technology Data Exchange (ETDEWEB)

    Pruett, J.G.

    1991-01-01

    Improved site characterization technologies are being developed at Martin Marietta Energy Systems for the US Department of Energy (DOE) Office of Technology Development (OTD) in support of environmental restoration activities throughout the DOE complex. Since site characterization is an expensive and time consuming process that must be performed prior to, during, and following remediation efforts, an obvious way to reduce the overall cost of remediation is to develop improved characterization methods. For example, the Derivative Ultraviolet Absorption Spectrometer (DUVAS), which is being field tested as part of the OTD program, is a fiberoptic device for in situ, real time measurement of aromatic organic compounds in groundwater. A transportable, direct sampling Ion Trap Mass Spectrometer (ITMS) is being developed for continuous monitoring of hazardous organic compounds in air. In areas where the environment is hazardous to human health, it is desirous to perform site characterization remotely; if robotics are to be employed, the Ultrasonic Ranging and Data System (USRADS) can be used to provide telemetry information on robot location as well as sensor measurements. Once fully developed, these technologies can be transferred to the private sector. 19 refs., 2 tabs.

  13. Data-worth analysis for multiobjective optimal design of pump-and-treat remediation systems

    Science.gov (United States)

    Baú, Domenico A.; Mayer, Alex S.

    2007-08-01

    The design and the management of pump-and-treat (PAT) remediation systems for contaminated aquifers under uncertain hydrogeological settings and parameters often involve decisions that trade off cost optimality against reliability. Both design objectives can be improved by planning site characterization programs that reduce subsurface parameter uncertainty. However, the cost for subsurface investigation often weighs heavily upon the budget of the remedial action and must thus be taken into account in the trade-off analysis. In this paper, we develop a stochastic data-worth framework with the purpose of estimating the economic opportunity of subsurface investigation programs. Since the spatial distribution of hydraulic conductivity is most often the major source of uncertainty, we focus on the direct sampling of hydraulic conductivity at prescribed locations of the aquifer. The data worth of hydraulic conductivity measurements is estimated from the reduction of the overall management cost ensuing from the reduction in parameter uncertainty obtained from sampling. The overall cost is estimated as the expected value of the cost of installing and operating the PAT system plus penalties incurred due to violations of cleanup goals and constraints. The crucial point of the data-worth framework is represented by the so-called pre-posterior analysis. Here, the tradeoff between decreasing overall costs and increasing site-investigation budgets is assessed to determine a management strategy proposed on the basis of the information available at the start of remediation. The goal of the pre-posterior analysis is to indicate whether the proposed management strategy should be implemented as is, or re-designed on the basis of additional data collected with a particular site-investigation program. The study indicates that the value of information is ultimately related to the estimates of cleanup target violations and decision makers' degree of risk-aversion.

  14. Modeling the Effects of Storm Surge from Hurricane Jeanne on Saltwater Intrusion into the Surficial Aquifer, East-Central Florida (USA)

    Science.gov (United States)

    Xiao, H.; Wang, D.; Hagen, S. C.; Medeiros, S. C.; Hall, C. R.

    2017-12-01

    Saltwater intrusion (SWI) that has been widely recognized as a detrimental issue causing the deterioration of coastal aquifer water quality and degradation of coastal ecosystems. While it is widely recognized that SWI is exacerbated worldwide due to global sea-level rise, we show that increased SWI from tropical cyclones under climate change is also a concern. In the Cape Canaveral Barrier Island Complex (CCBIC) located in east-central Florida, the salinity level of the surficial aquifer is of great importance to maintain a bio-diverse ecosystem and to support the survival of various vegetation species. Climate change induced SWI into the surficial aquifer can lead to reduction of freshwater storage and alteration of the distribution and productivity of vegetation communities. In this study, a three-dimensional variable-density SEAWAT model is developed and calibrated to investigate the spatial and temporal variation of salinity level in the surficial aquifer of CCBIC. We link the SEAWAT model to surge model data to examine the effects of storm surge from Hurricane Jeanne. Simulation results indicate that the surficial aquifer salinity level increases significantly right after the occurrence of storm surge because of high aquifer permeability and rapid infiltration and diffusion of the overtopping saltwater, while the surficial aquifer salinity level begins to decrease after the fresh groundwater recharge from the storm's rainfall. The tropical storm precipitation generates an effective hydraulic barrier further impeding SWI and providing seaward freshwater discharge for saltwater dilution and flushing. To counteract the catastrophic effects of storm surge, this natural remediation process may take at least 15-20 years or even several decades. These simulation results contribute to ongoing research focusing on forecasting regional vegetation community responses to climate change, and are expected to provide a useful reference for climate change adaptation planning

  15. State Aquifer Recharge Atlas Plates, Geographic NAD83, LDEQ (1999) [aquifer_recharge_potential_LDEQ_1988

    Data.gov (United States)

    Louisiana Geographic Information Center — This is a polygon dataset depicting the boundaries of aquifer systems in the state of Louisiana and adjacent areas of Texas, Arkansas and a portion of Mississippi....

  16. Can Remote Sensing Detect Aquifer Characteristics?: A Case Study in the Guarani Aquifer System

    Science.gov (United States)

    Richey, A. S.; Thomas, B.; Famiglietti, J. S.

    2013-12-01

    Global water supply resiliency depends on groundwater, especially regions threatened by population growth and climate change. Aquifer characteristics, even as basic as confined versus unconfined, are necessary to prescribe regulations to sustainably manage groundwater supplies. A significant barrier to sustainable groundwater management exists in the difficulties associated with mapping groundwater resources and characteristics at a large spatial scale. This study addresses this challenge by investigating if remote sensing, including with NASA's Gravity Recovery and Climate Experiment (GRACE), can detect and quantify key aquifer parameters and characteristics. We explore this through a case study in the Guarani Aquifer System (GAS) of South America, validating our remote sensing-based findings against the best available regional estimates. The use of remote sensing to advance the understanding of large aquifers is beneficial to sustainable groundwater management, especially in a trans-boundary system, where consistent information exchange can occur within hydrologic boundaries instead of political boundaries.

  17. Aquifer restoration: state of the art

    National Research Council Canada - National Science Library

    Knox, Robert C; Knox, R. C

    1986-01-01

    ... of chemicals or waste materials, improper underground injection of liquid wastes, and placement of septic tank systems in hydrologically and geologically unsuitable locations. Incidents of aquifer pollution from man's waste disposal activities have been discovered with increasing regularity. At the same time, demands for groundwater usage have been inc...

  18. Groundwater sustainability assessment in coastal aquifers

    Indian Academy of Sciences (India)

    The present work investigates the response of shallow, coastal unconfined aquifers to anticipated over- draft conditions and climate change effect using numerical simulation. The groundwater flow model. MODFLOW and variable density groundwater model SEAWAT are used for this investigation. The transmissivity and ...

  19. Aquifers Characterization and Productivity in Ellala Catchment ...

    African Journals Online (AJOL)

    user

    hydrogeological map, soil map, and lithology obtained from well logs, aquifer thickness as well as well inventory (Singhal ... Present paper makes use of the information provided by these drill holes; try to characterize different .... The dikes have intruded during upliftment and faulting in Cenozoic time. (Gebresilassie et al.

  20. 40 CFR 147.102 - Aquifer exemptions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.102 Section 147.102 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS...) Granite Point. (ii) McArthur River Field. (iii) Middle Ground Shoal Field. (iv) Trading Bay Field. (3) The...

  1. Geoelectric investigation of the aquifer characteristics and ...

    African Journals Online (AJOL)

    Subsurface geo-electrical survey using the electrical resistivity (VES) method and drillers logs were carried out in Kwale, Ndokwa West Local Government Area of Delta State in order to investigate the aquifer characteristics and ground water potential of the subsurface formations. Nineteen vertical electrical soundings were ...

  2. Groundwater sustainability assessment in coastal aquifers

    Indian Academy of Sciences (India)

    www.ias.ac.in/article/fulltext/jess/125/06/1103-1118 ... After successful calibration with Nash–Sutcliffe efficiency greater than 0.80, the values of horizontal hydraulic conductivity and specific yield of the unconfined aquifer were set in the range ...

  3. Groundwater sustainability assessment in coastal aquifers

    Indian Academy of Sciences (India)

    The present work investigates the response of shallow, coastal unconfined aquifers to anticipated overdraft conditions and climate change effect using numerical simulation. The groundwater flow model MODFLOW and variable density groundwater model SEAWAT are used for this investigation. The transmissivity and ...

  4. Managing environmental problems in Cuban karstic aquifers

    Science.gov (United States)

    León, Leslie Molerio; Parise, Mario

    2009-07-01

    The Cuban archipelago hosts some of the most typical karst features in the Caribbean, and has very important and high-quality resources of karst water. Carbonate rocks cover about 70% of the country area, with a great variety of karst features, and outstanding exokarstic landforms such as the cone karst; in addition, many caves are regarded as cultural and historical sites. Protection of the karst hydric resources is therefore essential. In karst, the intrinsic vulnerability of the environment makes it highly susceptible to pollution, which may result in dramatic consequences for both the quality of karst water and the amount of water available. Many anthropogenic activities produce negative changes in the karst aquifers, in some cases with unrecoverable effects. In Cuba, five main sources of pollution to karst aquifers have been identified: sea water intrusion, agricultural practices, waste disposal, industrial activity, and mining and oil production. Due to the narrow and elongated configuration of the main island, wide portions of the territory are mostly affected by seawater intrusion problems, exacerbated by the concentration of both population and human activities in the largest towns located along, or very close to, the coasts. Seawater intrusion, however, is not the only source of pollution for Cuban karst aquifers. The other aforementioned sources are important, and may locally prevail (e.g. pollution resulting from sugar cane factories). Considerations on the management of karst aquifers and a brief description of the water quality monitoring system of Cuban inland waters are also provided.

  5. 40 CFR 147.3003 - Aquifer exemptions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Aquifer exemptions. 147.3003 Section 147.3003 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) STATE, TRIBAL, AND EPA-ADMINISTERED UNDERGROUND INJECTION CONTROL PROGRAMS Lands of the Navajo...

  6. Hydrochemical characterization of groundwater aquifer using ...

    African Journals Online (AJOL)

    Hydrochemical data analysis revealed four sources of solutes. The processes responsible for their enrichment include: chemical weathering, leaching of the overlying sediments, domestic activities, climatic condition and the flow pattern of the aquifer. The factors have contributed to the changes of the groundwater chemistry ...

  7. Aquifer characterization and groundwater potential assessment of ...

    African Journals Online (AJOL)

    ... integrated electrical resistivity and borehole lithologic logs with a view to characterizing the aquifer and assessing the groundwater potential. One hundred and four Vertical Electrical Soundings (VES) were quantitatively interpreted using the partial curve matching technique and computer assisted 1-D forward modeling.

  8. Hydrochemistry and energy storage in aquifers

    NARCIS (Netherlands)

    Andersson, O.; Appelo, C.A.J.; Brons, H.J.; Dufour, F.C.; Griffioen, J.; Jenne, E.A.; Lyklema, J.W.; Mourik, G.J. van; Snijders, A.L.; Willemsen, A.; Zehnder, A.J.B.

    1990-01-01

    This volume of the series Proceedings and Information of the TNO Committee on Hydrological Research (CHO-TNO) contains the contributions as presented on the 48th technical meeting of the CHO-TNO, "Hydrochemistry and energy storage in aquifers". During this symposium recent results have been

  9. Biogeochemical aspects of aquifer thermal energy storage

    NARCIS (Netherlands)

    Brons, H.J.

    1992-01-01

    During the process of aquifer thermal energy storage the in situ temperature of the groundwater- sediment system may fluctuate significantly. As a result the groundwater characteristics can be considerably affected by a variety of chemical, biogeochemical and microbiological

  10. Biogeochemical aspects of uranium mineralization, mining, milling, and remediation

    Science.gov (United States)

    Campbell, Kate M.; Gallegos, Tanya J.; Landa, Edward R.

    2015-01-01

    Natural uranium (U) occurs as a mixture of three radioactive isotopes: 238U, 235U, and 234U. Only 235U is fissionable and makes up about 0.7% of natural U, while 238U is overwhelmingly the most abundant at greater than 99% of the total mass of U. Prior to the 1940s, U was predominantly used as a coloring agent, and U-bearing ores were mined mainly for their radium (Ra) and/or vanadium (V) content; the bulk of the U was discarded with the tailings (Finch et al., 1972). Once nuclear fission was discovered, the economic importance of U increased greatly. The mining and milling of U-bearing ores is the first step in the nuclear fuel cycle, and the contact of residual waste with natural water is a potential source of contamination of U and associated elements to the environment. Uranium is mined by three basic methods: surface (open pit), underground, and solution mining (in situ leaching or in situ recovery), depending on the deposit grade, size, location, geology and economic considerations (Abdelouas, 2006). Solid wastes at U mill tailings (UMT) sites can include both standard tailings (i.e., leached ore rock residues) and solids generated on site by waste treatment processes. The latter can include sludge or “mud” from neutralization of acidic mine/mill effluents, containing Fe and a range of coprecipitated constituents, or barium sulfate precipitates that selectively remove Ra (e.g., Carvalho et al., 2007). In this chapter, we review the hydrometallurgical processes by which U is extracted from ore, the biogeochemical processes that can affect the fate and transport of U and associated elements in the environment, and possible remediation strategies for site closure and aquifer restoration.This paper represents the fourth in a series of review papers from the U.S. Geological Survey (USGS) on geochemical aspects of UMT management that span more than three decades. The first paper (Landa, 1980) in this series is a primer on the nature of tailings and radionuclide

  11. Drama, dissensus, remediation and a fluttering butterfly

    DEFF Research Database (Denmark)

    Kusk, Hanne

    2017-01-01

    Why is it important to pay attention to democracy and polyphony when working with remediation in a multimodal drama project in introductory schooling? This question is elucidated and investigated in this article on the basis of a drama project case study conducted at Hundborg Friskole. The study......-based process of remediation, and how this impacts children’s democratic education....

  12. Remedial principles and meaningful engagement in education ...

    African Journals Online (AJOL)

    This article evaluates the meaningful engagement doctrine in the education rights jurisprudence of the Constitutional Court in the light of a set of normative principles developed by Susan Sturm for evaluating participatory public law remedies. It commences by identifying four principles for evaluating participatory remedies ...

  13. Remediation of the Maxey Flats Site

    International Nuclear Information System (INIS)

    1990-01-01

    This report describes issues associated with remedial action of Maxey Flats, a low-level radioactive waste disposal site from 1963-1977, located in Fleming County, Kentucky. Present remedial action alternatives being considered are discussed along with emergency plans, ground water monitoring plans, and budgets

  14. Laboratory Experiment on Electrokinetic Remediation of Soil

    Science.gov (United States)

    Elsayed-Ali, Alya H.; Abdel-Fattah, Tarek; Elsayed-Ali, Hani E.

    2011-01-01

    Electrokinetic remediation is a method of decontaminating soil containing heavy metals and polar organic contaminants by passing a direct current through the soil. An undergraduate chemistry laboratory is described to demonstrate electrokinetic remediation of soil contaminated with copper. A 30 cm electrokinetic cell with an applied voltage of 30…

  15. Arsenic release during managed aquifer recharge (MAR)

    Science.gov (United States)

    Pichler, T.; Lazareva, O.; Druschel, G.

    2013-12-01

    The mobilization and addition of geogenic trace metals to groundwater is typically caused by anthropogenic perturbations of the physicochemical conditions in the aquifer. This can add dangerously high levels of toxins to groundwater, thus compromising its use as a source of drinking water. In several regions world-wide, aquifer storage and recovery (ASR), a form of managed aquifer recharge (MAR), faces the problem of arsenic release due to the injection of oxygenated storage water. To better understand this process we coupled geochemical reactive transport modeling to bench-scale leaching experiments to investigate and verify the mobilization of geogenic arsenic (As) under a range of redox conditions from an arsenic-rich pyrite bearing limestone aquifer in Central Florida. Modeling and experimental observations showed similar results and confirmed the following: (1) native groundwater and aquifer matrix, including pyrite, were in chemical equilibrium, thus preventing the release of As due to pyrite dissolution under ambient conditions; (2) mixing of oxygen-rich surface water with oxygen-depleted native groundwater changed the redox conditions and promoted the dissolution of pyrite, and (3) the behavior of As along a flow path was controlled by a complex series of interconnected reactions. This included the oxidative dissolution of pyrite and simultaneous sorption of As onto neo-formed hydrous ferric oxides (HFO), followed by the reductive dissolution of HFO and secondary release of adsorbed As under reducing conditions. Arsenic contamination of drinking water in these systems is thus controlled by the re-equilibration of the system to more reducing conditions rather than a purely oxidative process.

  16. Proceedings of the remediation technologies symposium 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This conference provided an opportunity for industry, practitioners, researchers and regulators to discuss technical issues in environmental remediation research and the latest innovations in soil and groundwater remediation. Cost effective in-situ and ex-situ soil reclamation strategies were presented along with groundwater and surface water remediation strategies in 13 sessions entitled: hydrocarbon contamination; salt management; liability management; chemical oxidation; light non-aqueous phase liquids (LNAPL); Montreal Center of Excellence in Brownfields Rehabilitation; Alberta government updates; phytoremediation; natural attenuation; Lake Wabamun; ex-situ remediation; in-situ remediation; and, miscellaneous issues. Technological solutions for erosion control and water clarification were highlighted. The conference featured 52 presentations, of which 17 have been catalogued separately for inclusion in this database. tabs., figs.

  17. Use of in-situ Dual Vacuum Extraction trademark for remediation of soil and ground water

    International Nuclear Information System (INIS)

    Dodson, M.E.; Trowbridge, B.E.; Ott, D.

    1994-01-01

    Dual Vacuum Extraction trademark provides a rapid and cost-effective method of remediating soil and ground water contaminated with volatile organic compounds. The system involves the removal of both water and vapors through the same borehole by use of entrainment. This technology provides for the remediation of the vadose zone, capillary fringe, smear zone, and existing water table. The effectiveness of this technology is shown in a case study. A release from an underground storage tank was responsible for a hydrocarbon plume spreading over approximately 50,000 ft 2 . The release produced vadose-zone contamination in the silty and sandy clays from 10 to 30 ft below ground surface (bgs) with total petroleum hydrocarbon (TPH) concentrations up to 1,400 mg/kg. In addition, a layer of free-floating liquid hydrocarbon was present on a shallow aquifer located at 25 ft bgs in thicknesses ranging from 0.5 to 3.0 ft. An in-situ dual-extraction system was installed to remediate the soils and ground water to levels as required by the Los Angeles Regional Water Quality Control Board (RWQCB). The system operated 24 hr a day, with an operating efficiency of over 99%. After 196 days (28 weeks), over 17,000 lb of hydrocarbons had been extracted from the soils. Seven confirmatory soil borings in the area of highest initial hydrocarbon concentrations indicated that TPH and benzene, toluene, ethylbenzene, xylene (BTEX) concentrations had decreased over 99% from initial soil concentrations

  18. Selected remedy at the Queen City Farms superfund site: A risk management approach

    International Nuclear Information System (INIS)

    Weber, E.F.; Wilson, J.; Kirk, M.; Tochko, S.

    1994-01-01

    A risk management approach at a former industrial waste disposal site in western Washington resulted in a selected remedy that is cost-effective and that meets the CERCLA threshold criterion of protecting human health and the environment. The proposed remedy, which addresses contamination in soil and groundwater, does not require an ARARs waiver and received state and community acceptance. By analyzing the current and potential risk at the site, a proposed remedy was chosen that would control the source and naturally attenuate the groundwater plume. Source control will include removal and treatment of some light nonaqueous phase liquid (LNAPL) and some soil, followed by isolation of the remaining soil and LNAPL within a slurry wall and beneath a multilayer cap. A contingent groundwater extraction and treatment system was included to address uncertainty in the risk characterization. Implementing source control is predicted to result in a steady decline in volatile organic compound levels in the drinking water aquifer through adsorption, degradation, and dispersion. Exposure to groundwater during the period of natural attenuation will be controlled by monitoring, institutional controls, and a thorough characterization of the plume and receptors. 7 figs., 1 tab

  19. Hydrogeology - AQUIFER_SYSTEMS_BEDROCK_IDNR_IN: Bedrock Aquifer Systems of Indiana (Indiana Department of Natural Resources, 1:500,000, Polygon Shapefile)

    Data.gov (United States)

    NSGIC State | GIS Inventory — AQUIFER_SYSTEMS_BEDROCK_IDNR_IN is a polygon shapefile that shows bedrock aquifer systems of the State of Indiana. The source scale of the map depicting the aquifers...

  20. Light Pollution Responses and Remedies

    CERN Document Server

    Mizon, Bob

    2012-01-01

    Light pollution is a major threat to astronomy across the entire developed world. The night sky that most of us can see bears little relationship to the spectacular vistas that our ancestors have gazed at for tens of thousands of years. It is ironic that as our understanding of the universe has improved, our ability to see it has been dramatically reduced by the skyglow of our civilization. In the second edition of Light Pollution - Responses and Remedies, Bob Mizon delves into the history and practice of lighting and how its misue has not only stolen the stars, but blighted our lives and those of our fellow-creatures on this planet. This book suggests how we can win back the night sky and at the same time save energy and money, improve our health, and even lower crime rate! It also includes a list of targets for urban stargazers, and recommendations for ensuring sane lighting worldwide.

  1. Remedial transactions curtailment via optimization

    Directory of Open Access Journals (Sweden)

    Maksimović Viktor

    2009-01-01

    Full Text Available The new method developed in this paper is aiming at transmission congestion management (CM. The new, Optimal Transactions Management method (OTM, is based on linear programming (LP, DC load flow (DCLF and linear security constraints. The OTM method is embedded in Available Transfer Capabilities (ATCs and Power Transfer Distribution Factors (PTDFs definitions' environment. Well-suited for both preventive and corrective modes of operation, the OTM method aids transmission system operator in running a congested power system network, where congestions are due to transactions. Potential congestion threat is solved by finding the 'culprit' transaction and its optimal reduction. Besides the proposed downsizing of scheduled and/or committed transactions, controls of the OTM method also include redispatching of generation and load levels. The task is to establish a system state without constraint violations. To ensure the feasible network solution, both DC and AC power flows are used. The common 5 nodes/7 lines Ward&Hale sample power system is used to clarify the OTM method. Besides, six other power system networks including the real-life power system network of Serbia, Macedonia and Montenegro (part of the South East Europe - SEE grid are used to test remedial potentials and CPU-time performances of the method. The 24-hour daily demand diagram is used with all test networks to study the effects of transactions as they are being superimposed to the regional grid. The remedial, transactions-curtailing OTM method is found well suited for market-related analyses precluding the hour-ahead, the day-ahead dispatch, as well as the real-time generation dispatch. It could also suit for the novel, Day Ahead Congestion Forecast (DACF procedure used in power markets. .

  2. Innovative vitrification for soil remediation

    International Nuclear Information System (INIS)

    Jetta, N.W.; Patten, J.S.; Hart, J.G.

    1995-01-01

    The objective of this DOE demonstration program is to validate the performance and operation of the Vortec Cyclone Melting System (CMS trademark) for the processing of LLW contaminated soils found at DOE sites. This DOE vitrification demonstration project has successfully progressed through the first two phases. Phase 1 consisted of pilot scale testing with surrogate wastes and the conceptual design of a process plant operating at a generic DOE site. The objective of Phase 2, which is scheduled to be completed the end of FY 95, is to develop a definitive process plant design for the treatment of wastes at a specific DOE facility. During Phase 2, a site specific design was developed for the processing of LLW soils and muds containing TSCA organics and RCRA metal contaminants. Phase 3 will consist of a full scale demonstration at the DOE gaseous diffusion plant located in Paducah, KY. Several DOE sites were evaluated for potential application of the technology. Paducah was selected for the demonstration program because of their urgent waste remediation needs as well as their strong management and cost sharing financial support for the project. During Phase 2, the basic nitrification process design was modified to meet the specific needs of the new waste streams available at Paducah. The system design developed for Paducah has significantly enhanced the processing capabilities of the Vortec vitrification process. The overall system design now includes the capability to shred entire drums and drum packs containing mud, concrete, plastics and PCB's as well as bulk waste materials. This enhanced processing capability will substantially expand the total DOE waste remediation applications of the technology

  3. Flow assurance intervention, hydrates remediation

    Energy Technology Data Exchange (ETDEWEB)

    Mancini, Christopher S. [Oceaneering International Inc., Houston, TX (United States)

    2012-07-01

    This paper addresses the issues of removing hydrates in sub sea flow lines and associated equipment with an Remotely Operated Vehicle (ROV) of opportunity and a multi-service-vessel (MSV). The paper is split into three topics: the equipment used with the ROV, assessing the interface points and handling fluids produced from drawing down the pressure. Each section is explained thoroughly and backed up with real world experience. The equipment section details information from actual jobs performed and why the particular components were utilized. The system is generally contained in an ROV mounted skid. Pumps are utilized to draw down the pressure inside the hydrated section of equipment, removing one of the three necessary components for hydrates formation. Once the section is pumped down, several options exist for handling the fluids pumped out of the system: pumping to surface, re-injection into the well, or injection into an operating flow line. This method of hydrates remediation is both economical and timely. Hydrate blockages form in low temperatures and high pressures. Reducing the pressure or increasing the temperature so the conditions lie to the right of the hydrate dissociation curve will slowly decompose the blockage. Depressurization and the use of MEG or methanol will give favorable conditions to remove the hydrate plug. Oceaneering has the capabilities to remove hydrates using the FRS in conjunction with an installation vessel to dispose of the gas and fluid removed from the flow line. Hydrate remediation techniques should be implemented into the initial design to reduce costs later. The cost of stopped production combined with the day rate for equipment needed for hydrate removal outweighs the costs if no technique is utilized. (author)

  4. Surfactant-enhanced control of track-etch pore morphology

    International Nuclear Information System (INIS)

    Apel', P.Yu.; Blonskaya, I.V.; Didyk, A.Yu.; Dmitriev, S.N.; Orelovich, O.L.; Samojlova, L.I.; Vutsadakis, V.A.; Root, D.

    2000-01-01

    The influence of surfactants on the process of chemical development of ion tracks in polymers is studied. Based on the experimental data, a mechanism of the surfactant effect on the track-etch pore morphology is proposed. In the beginning of etching the surfactant is adsorbed on the surface and creates a layer that is quasi-solid and partially protects the surface from the etching agent. However, some etchant molecules diffuse through the barrier and react with the polymer surface. This results in the formation of a small hole at the entrance to the ion track. After the hole has attained a few annometers in diameter, the surfactant molecules penetrate into the track and cover its walls. Further diffusion of the surfactant into the growing pore is hindered. The adsorbed surfactant layer is not permeable for large molecules. In contrast, small alkali molecules and water molecules diffuse into the track and provide the etching process enlarging the pore. At this stage the transport of the surfactant into the pore channel can proceed only due to the lateral diffusion in the adsorbed layer. The volume inside the pore is free of surfactant molecules and grows at a higher rate than pore entrance. After a more prolonged etching the bottle-like (or 'cigar-like') pore channels are formed. The bottle-like shape of the pore channels depends on the etching conditions such as alkali and surfactant concentration, temperature, and type of the surfactant. The use of surfactants enables one to produce track-etch membranes with improved flow rate characteristics compared with those having cylindrical pores with the same nominal pore diameters

  5. Surfactant Enhanced Chromium Removal Using a Silica Gel Column

    Directory of Open Access Journals (Sweden)

    N. Rajesh

    2001-06-01

    Full Text Available A simple and rapid method is proposed for the removal of chromium based on its adsorption as an ion pair with Cetyl Trimethyl Ammonium Bromide (CTABr on a silica gel colurnn. The surfactant (CTABr is bonded to chromate by electrostatic force of attraction and the resulting ion-association complex is held on a silica gel column. The resulting solution from the column is analyzed for chromium by the standard diphenyl carbazide spectrophotometric procedure. The method has been applied successfully to study the recovery of chromium in various synthetic mixtures.

  6. Surfactants enhance recovery of poorly soluble drugs during microdialysis sampling

    DEFF Research Database (Denmark)

    Koplin, Sebastian; Kumpugdee-Vollrath, Mont; Bauer-Brandl, Annette

    2017-01-01

    Aim of this project was to investigate the applicability of a recently developed in vitro microdialysis-sampling approach in connection with a dissolution-/permeation (D/P) system, especially the impact of surfactants within the perfusion fluid. The D/P-system is based on side-by-side chambers...... drug-dissolution (-release) and drug permeation. Furthermore, it should allow quantification of the unbound (free) drug concentration. In the first step, it was assessed, if the addition of the anionic surfactant sodium dodecyl sulphate (SDS) to the perfusate of the microdialysis system affects...... celecoxib, i.e. the fraction of drug, which is not associated with taurocholate surfactant micelles. In buffer, the measured concentrations matched the overall CXB concentrations. By the use of SDS-containing perfusates microdialysis sampling enabled reliable quantification of minute amounts of free CXB...

  7. Surfactant Enhanced Microbial Degradation of JP-8 Contaminated Soil

    Science.gov (United States)

    1996-12-01

    Halogenated Aromatics PCBs Branched Alkanes In the deeper areas of the unsaturated zone there are 106 to 107 organisms per gram of dry soil (Mitchell...semialdehyde ( OH Smuconate- lactonizing 2-hydroxymuconic enzyme Isemialdehyde hydrolase (2 OOH CH2 OOH muconolactone 0 0 2-oxopent-4-enoate Further...and sodium dodecyl sulfate (SDS). Both unsaturated and saturated conditions were investigated in this study. The tests revealed that all of the

  8. Physics of DNAPL Migration and Remediation in the Presence of Heterogeneities; TOPICAL

    International Nuclear Information System (INIS)

    CONRAD, STEPHEN H.; GLASS, ROBERT J.

    1999-01-01

    The goal of our research is to develop a fundamental quantitative understanding of the role of physical heterogeneities on DNAPL migration and remediation in aquifers. Such understanding is critical to cost effectively identify the location of the subsurface zone of contamination and design remediation schemes focused on removing the source of the contamination, the DNAPL itself. To reach this goal, the following objectives for the proposed research are defined: Objective 1: Develop fundamental understanding of the physics of DNAPL migration processes within heterogeneous porous media: (a) Conduct a suite of two-dimensional physical experiments within controlled and systematically varied heterogeneous porous media at scales up to one meter. Vary system parameters to consider a range of capillary and bond numbers within these heterogeneous porous structures. (b) Develop a new DNAPL migration model based on an up-scaling of invasion percolation (UP) to model the migration process. Compare the model predictions to experimental results. Accomplishing objective 1 provides a series of experiments against which we will be able to evaluate the validity of existing multi-phase flow theory as formulated in both percolation codes and in continuum flow codes. These experimental results will also provide new insights into DNAPL migration behavior. Development of the UIP model will provide an exciting alternative to continuum multi-phase flow codes since UIP offers several advantages for modeling DNAPL migration. The UIP model is fast, allowing for: (1) modeling in three dimensions; (2) the incorporation of much more geologic detail; and (3) its use in probabilistic modeling by way of Monte Carlo techniques. Objective 2: Develop fundamental understanding of the physics of DNAPL remediation processes within heterogeneous porous media: Conduct a suite of physical experiments within controlled and systematically varied heterogeneous porous media at scales up to one meter that

  9. Policy and Strategies for Environmental Remediation

    International Nuclear Information System (INIS)

    2015-01-01

    In the environmental remediation of a given site, concerned and interested parties have diverse and often conflicting interests with regard to remediation goals, the time frames involved, reuse of the site, the efforts necessary and cost allocation. An environmental remediation policy is essential for establishing the core values on which remediation is to be based. It incorporates a set of principles to ensure the safe and efficient management of remediation situations. Policy is mainly established by the national government and may become codified in the national legislative system. An environmental remediation strategy sets out the means for satisfying the principles and requirements of the national policy. It is normally established by the relevant remediation implementer or by the government in the case of legacy sites. Thus, the national policy may be elaborated in several different strategies. To ensure the safe, technically optimal and cost effective management of remediation situations, countries are advised to formulate an appropriate policy and strategies. Situations involving remediation include remediation of legacy sites (sites where past activities were not stringently regulated or adequately supervised), remediation after emergencies (nuclear and radiological) and remediation after planned ongoing operation and decommissioning. The environmental policy involves the principles of justification, optimization of protection, protection of future generations and the environment, efficiency in the use of resources, and transparent interaction with stakeholders. A typical policy will also take into account the national legal framework and institutional structure and applicable international conventions while providing for the allocation of responsibilities and resources, in addition to safety and security objectives and public information and participation in the decision making process. The strategy reflects and elaborates the goals and requirements set

  10. San Pedro River Aquifer Binational Report

    Science.gov (United States)

    Callegary, James B.; Minjárez Sosa, Ismael; Tapia Villaseñor, Elia María; dos Santos, Placido; Monreal Saavedra, Rogelio; Grijalva Noriega, Franciso Javier; Huth, A. K.; Gray, Floyd; Scott, C. A.; Megdal, Sharon; Oroz Ramos, L. A.; Rangel Medina, Miguel; Leenhouts, James M.

    2016-01-01

    The United States and Mexico share waters in a number of hydrological basins and aquifers that cross the international boundary. Both countries recognize that, in a region of scarce water resources and expanding populations, a greater scientific understanding of these aquifer systems would be beneficial. In light of this, the Mexican and U.S. Principal Engineers of the International Boundary and Water Commission (IBWC) signed the “Joint Report of the Principal Engineers Regarding the Joint Cooperative Process United States-Mexico for the Transboundary Aquifer Assessment Program" on August 19, 2009 (IBWC-CILA, 2009). This IBWC “Joint Report” serves as the framework for U.S.-Mexico coordination and dialogue to implement transboundary aquifer studies. The document clarifies several details about the program such as background, roles, responsibilities, funding, relevance of the international water treaties, and the use of information collected or compiled as part of the program. In the document, it was agreed by the parties involved, which included the IBWC, the Mexican National Water Commission (CONAGUA), the U.S. Geological Survey (USGS), and the Universities of Arizona and Sonora, to study two priority binational aquifers, one in the San Pedro River basin and the other in the Santa Cruz River basin. This report focuses on the Binational San Pedro Basin (BSPB). Reasons for the focus on and interest in this aquifer include the fact that it is shared by the two countries, that the San Pedro River has an elevated ecological value because of the riparian ecosystem that it sustains, and that water resources are needed to sustain the river, existing communities, and continued development. This study describes the aquifer’s characteristics in its binational context; however, most of the scientific work has been undertaken for many years by each country without full knowledge of the conditions on the other side of the border. The general objective of this study is to

  11. Evaluation and Screening of Remedial Technologies for Uranium at the 300-FF-5 Operable Unit, Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Nimmons, Michael J.

    2007-08-01

    Pacific Northwest National Laboratory (PNNL) is presently conducting a re-evaluation of remedies addressing persistent dissolved uranium concentrations in the upper aquifer under the 300 Area of the Hanford Site in southeastern Washington State. This work is being conducted as a Phase III feasibility study for the 300-FF-5 Operable Unit on behalf of the U.S. Department of Energy. As part of the feasibility study process, a comprehensive inventory of candidate remedial technologies was conducted by PNNL. This report documents the identification and screening of candidate technologies. The screening evaluation was conducted in accordance with guidance and processes specified by U.S. Environmental Protection Agency regulations associated with implementation of the Comprehensive Environmental Response, Compensation, and Liability Act process.

  12. Evaluation of French Guiana traditional antimalarial remedies.

    Science.gov (United States)

    Bertani, S; Bourdy, G; Landau, I; Robinson, J C; Esterre, Ph; Deharo, E

    2005-04-08

    In order to evaluate the antimalarial potential of traditional remedies used in French Guiana, 35 remedies were prepared in their traditional form and screened for blood schizonticidal activity in vitro on Plasmodium falciparum chloroquine re4sistant strain (W2). Some of these extracts were screened in vivo against Plasmodium yoelii rodent malaria. Ferriprotoporphyrin inhibition test was also performed. Four remedies, widely used among the population as preventives, were able to inhibit more than 50% of the parasite growth in vivo at around 100 mg/kg: Irlbachia alata (Gentiananceae), Picrolemma pseudocoffea (Simaroubaceae), Quassia amara (Simaroubaceae), Tinospora crispa (Menispermaceae) and Zanthoxylum rhoifolium (Rutaceae). Five remedies displayed an IC50 in vitro < 10 microg/ml: Picrolemma pseudocoffea, Pseudoxandra cuspidata (Annonaceae) and Quassia amara leaves and stem, together with a multi-ingredient recipe. Two remedies were more active than a Cinchona preparation on the ferriprotoporphyrin inhibition test: Picrolemma pseudocoffea and Quassia amara. We also showed that a traditional preventive remedy, made from Geissospermum argenteum bark macerated in rum, was able to impair the intrahepatic cycle of the parasite. For the first time, traditional remedies from French Guiana have been directly tested on malarial pharmacological assays and some have been shown to be active.

  13. Risk-based remediation: Approach and application

    International Nuclear Information System (INIS)

    Frishmuth, R.A.; Benson, L.A.

    1995-01-01

    The principle objective of remedial actions is to protect human health and the environment. Risk assessments are the only defensible tools available to demonstrate to the regulatory community and public that this objective can be achieved. Understanding the actual risks posed by site-related contamination is crucial to designing cost-effective remedial strategies. All to often remedial actions are overdesigned, resulting in little to no increase in risk reduction while increasing project cost. Risk-based remedial actions have recently been embraced by federal and state regulators, industry, government, the scientific community, and the public as a mechanism to implement rapid and cost-effective remedial actions. Emphasizing risk reduction, rather than adherence to ambiguous and generic standards, ensures that only remedial actions required to protect human health and the environment at a particular site are implemented. Two sites are presented as case studies on how risk-based approaches are being used to remediate two petroleum hydrocarbon contaminated sites. The sites are located at two US Air Force Bases, Wurtsmith Air Force Base (AFB) in Oscoda, Michigan and Malmstrom AFB in Great Falls, Montana

  14. DOE's Assurance Program for Remedial Action (APRA)

    International Nuclear Information System (INIS)

    Denham, D.H.; Stenner, R.D.; Welty, C.G. Jr.; Needels, T.S.

    1985-01-01

    The US Department of Energy's (DOE) Office of Operational Safety (OOS) is presently developing and implementing the Assurance Program for Remedial Action (APRA) to overview DOE's Remedial Action programs. APRA's objective is to ensure the adequacy of environmental, safety and health (ES and H) protection practices within the four DOE Remedial Action programs: Grand Junction Remedial Action Program (GJRAP), Uranium Mill Tailings Remedial Action Program (UMTRAP), Formerly Utilized Sites Remedial Action Program (FUSRAP), and Surplus Facilities Management Program (SFMP). APRA encompasses all ES and H practices of DOE and its contractors/subcontractors within the four Remedial Action programs. Specific activities of APRA include document reviews, selected site visits, and program office appraisals. Technical support and assistance to OOS is being provided by APRA contractors in the evaluation of radiological standards and criteria, quality assurance measures, radiation measurements, and risk assessment practices. This paper provides an overview of these activities and discusses program to date, including the roles of OOS and the respective contractors. The contractors involved in providing technical support and assistance to OOS are Aerospace Corporation, Oak Ridge Associated Universities, and Pacific Northwest Laboratory

  15. DOE's Assurance Program for Remedial Action (APRA)

    International Nuclear Information System (INIS)

    Denham, D.H.; Stenner, R.D.; Welty, C.G. Jr.; Needels, T.S.

    1984-10-01

    The US Department of Energy's (DOE) Office of Operational Safety (OOS) is presently developing and implementing the Assurance Program for Remedial Action (APRA) to overview DOE's Remedial Action programs. APRA's objective is to ensure the adequacy of environmental, safety and health (ES and H) protection practices within the four DOE Remedial Action programs: Grand Junction Remedial Action Program (GJRAP), Uranium Mill Tailings Remedial Action Program (UMTRAP), Formerly Utilized Sites Remedial Action Program (FUSRAP), and Surplus Facilities Management Program (SFMP). APRA encompasses all ES and H practices of DOE and its contractors/subcontractors within the four Remedial Action programs. Specific activities of APRA include document reviews, selected site visits, and program office appraisals. Technical support and assistance to OOS is being provided by APRA contractors in the evaluation of radiological standards and criteria, quality assurance measures, radiation measurements, and risk assessment practices. This paper provides an overview of these activities and discusses progress to date, including the roles of OOS and the respective contractors. The contractors involved in providing technical support and assistance to OOS are Aerospace Corporation, Oak Ridge Associated Universities, and Pacific Northwest Laboratory

  16. Capture zone of a multi-well system in confined and unconfined wedge-shaped aquifers

    Science.gov (United States)

    Samani, Nozar; Zarei-Doudeji, Somayeh

    2012-04-01

    In this paper we present the equation of capture zone of a multi-well system in wedge-shaped confined and unconfined aquifers. Three wedge boundary configurations: barrier-barrier wedge, barrier-constant head wedge and constant head-constant head wedge are considered. The well system may be consisted of any number of production or injection wells or a combination of both with various flow rates. Method of image wells is used in the wedge-shaped domain and an appropriate complex function is formulated to find the capture zone. The stream function and velocity potential are derived from the imaginary part and real part of the complex function, respectively. Solutions are provided for the wedge domains with and without a uniform regional flow and can also be used for aquifers of infinite extent. The presented equations are of general character and have removed the limitations of the previous equations in regards to well numbers, positions and types, extraction/injection rate, and regional flow rate and direction. Capture envelopes are presented in dimensionless form which can be used as tools in real engineering practices to plan pump-and-treat operations, groundwater remediation projects or well-head protection plans. It is also demonstrated that the equations may also be used for the verification of numerical models. The developed equations are constrained by the image well theory limitations.

  17. Technologies for remediation of radioactively contaminated sites

    International Nuclear Information System (INIS)

    1999-06-01

    This report presents particulars on environmental restoration technologies (control and treatment) which can be applied to land based, radioactively contaminated sites. The media considered include soils, groundwater, surface water, sediments, air, and terrestrial and aquatic vegetation. The technologies addressed in this report can be categorized as follows: self-attenuation (natural restoration); in-situ treatment; removal of contamination; ex-situ treatment; and transportation and final disposal. The report provides also background information about and a general approach to remediation of radioactively contaminated sites as well as some guidance for the selection of a preferred remediation technology. Examples of remediation experience in Australia and Canada are given it annexes

  18. Remedial investigations for quarry bulk wastes

    International Nuclear Information System (INIS)

    1989-12-01

    The US Department of Energy proposes, as a separate operable unit of the Weldon Spring Site Remedial Action Project, to remove contaminated bulk wastes from the Weldon Spring quarry and transport them approximately four miles to the chemical plant portion of the raffinate pits and chemical plant area. The wastes will be held in temporary storage prior to the record of decision for the overall remedial action. The decision on the ultimate disposal of these bulk wastes will be included as part of the decision for management of the waste materials resulting from remedial action activities at the raffinate pits and chemical plant area. 86 refs., 71 figs., 83 tabs

  19. Lessons Learned from Environmental Remediation Programmes

    International Nuclear Information System (INIS)

    2014-01-01

    Several remediation projects have been developed to date, and experience with these projects has been accumulated. Lessons learned span from non-technical to technical aspects, and need to be shared with those who are beginning or are facing the challenge to implement environmental remediation works. This publication reviews some of these lessons. The key role of policy and strategies at the national level in framing the conditions in which remediation projects are to be developed and decisions made is emphasized. Following policy matters, this publication pays attention to the importance of social aspects and the requirement for fairness in decisions to be made, something that can only be achieved with the involvement of a broad range of interested parties in the decision making process. The publication also reviews the funding of remediation projects, planning, contracting, cost estimates and procurement, and issues related to long term stewardship. Lessons learned regarding technical aspects of remediation projects are reviewed. Techniques such as the application of cover systems and soil remediation (electrokinetics, phytoremediation, soil flushing, and solidification and stabilization techniques) are analysed with respect to performance and cost. After discussing soil remediation, the publication covers issues associated with water treatment, where techniques such as ‘pump and treat’ and the application of permeable barriers are reviewed. Subsequently, there is a section dedicated to reviewing briefly the lessons learned in the remediation of uranium mining and processing sites. Many of these sites throughout the world have become orphaned, and are waiting for remediation. The publication notes that little progress has been made in the management of some of these sites, particularly in the understanding of associated environmental and health risks, and the ability to apply prediction to future environmental and health standards. The publication concludes

  20. Source, variability, and transformation of nitrate in a regional karst aquifer: Edwards aquifer, central Texas

    Energy Technology Data Exchange (ETDEWEB)

    Musgrove, M., E-mail: mmusgrov@usgs.gov [U.S. Geological Survey, 1505 Ferguson Lane, Austin, TX 78754 (United States); Opsahl, S.P. [U.S. Geological Survey, 5563 DeZavala, Ste. 290, San Antonio, TX 78249 (United States); Mahler, B.J. [U.S. Geological Survey, 1505 Ferguson Lane, Austin, TX 78754 (United States); Herrington, C. [City of Austin Watershed Protection Department, Austin, TX 78704 (United States); Sample, T.L. [U.S. Geological Survey, 19241 David Memorial Dr., Ste. 180, Conroe, TX 77385 (United States); Banta, J.R. [U.S. Geological Survey, 5563 DeZavala, Ste. 290, San Antonio, TX 78249 (United States)

    2016-10-15

    Many karst regions are undergoing rapid population growth and expansion of urban land accompanied by increases in wastewater generation and changing patterns of nitrate (NO{sub 3}{sup −}) loading to surface and groundwater. We investigate variability and sources of NO{sub 3}{sup −} in a regional karst aquifer system, the Edwards aquifer of central Texas. Samples from streams recharging the aquifer, groundwater wells, and springs were collected during 2008–12 from the Barton Springs and San Antonio segments of the Edwards aquifer and analyzed for nitrogen (N) species concentrations and NO{sub 3}{sup −} stable isotopes (δ{sup 15}N and δ{sup 18}O). These data were augmented by historical data collected from 1937 to 2007. NO{sub 3}{sup −} concentrations and discharge data indicate that short-term variability (days to months) in groundwater NO{sub 3}{sup −} concentrations in the Barton Springs segment is controlled by occurrence of individual storms and multi-annual wet-dry cycles, whereas the lack of short-term variability in groundwater in the San Antonio segment indicates the dominance of transport along regional flow paths. In both segments, longer-term increases (years to decades) in NO{sub 3}{sup −} concentrations cannot be attributed to hydrologic conditions; rather, isotopic ratios and land-use change indicate that septic systems and land application of treated wastewater might be the source of increased loading of NO{sub 3}{sup −}. These results highlight the vulnerability of karst aquifers to NO{sub 3}{sup −} contamination from urban wastewater. An analysis of N-species loading in recharge and discharge for the Barton Springs segment during 2008–10 indicates an overall mass balance in total N, but recharge contains higher concentrations of organic N and lower concentrations of NO{sub 3}{sup −} than does discharge, consistent with nitrification of organic N within the aquifer and consumption of dissolved oxygen. This study demonstrates

  1. Numerical Validation of Chemical Compositional Model for Wettability Alteration Processes

    Science.gov (United States)

    Bekbauov, Bakhbergen; Berdyshev, Abdumauvlen; Baishemirov, Zharasbek; Bau, Domenico

    2017-12-01

    Chemical compositional simulation of enhanced oil recovery and surfactant enhanced aquifer remediation processes is a complex task that involves solving dozens of equations for all grid blocks representing a reservoir. In the present work, we perform a numerical validation of the newly developed mathematical formulation which satisfies the conservation laws of mass and energy and allows applying a sequential solution approach to solve the governing equations separately and implicitly. Through its application to the numerical experiment using a wettability alteration model and comparisons with existing chemical compositional model's numerical results, the new model has proven to be practical, reliable and stable.

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

    Science.gov (United States)

    Wilkison, Donald H.

    2012-01-01

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

  3. Evidence of remediation-induced alteration of subsurface poly- and perfluoroalkyl substance distribution at a former firefighter training area.

    Science.gov (United States)

    McGuire, Meghan E; Schaefer, Charles; Richards, Trenton; Backe, Will J; Field, Jennifer A; Houtz, Erika; Sedlak, David L; Guelfo, Jennifer L; Wunsch, Assaf; Higgins, Christopher P

    2014-06-17

    Poly- and perfluoroalkyl substances (PFASs) are a class of fluorinated chemicals that are utilized in firefighting and have been reported in groundwater and soil at several firefighter training areas. In this study, soil and groundwater samples were collected from across a former firefighter training area to examine the extent to which remedial activities have altered the composition and spatial distribution of PFASs in the subsurface. Log Koc values for perfluoroalkyl acids (PFAAs), estimated from analysis of paired samples of groundwater and aquifer solids, indicated that solid/water partitioning was not entirely consistent with predictions based on laboratory studies. Differential PFAA transport was not strongly evident in the subsurface, likely due to remediation-induced conditions. When compared to the surface soil spatial distributions, the relative concentrations of perfluorooctanesulfonate (PFOS) and PFAA precursors in groundwater strongly suggest that remedial activities altered the subsurface PFAS distribution, presumably through significant pumping of groundwater and transformation of precursors to PFAAs. Additional evidence for transformation of PFAA precursors during remediation included elevated ratios of perfluorohexanesulfonate (PFHxS) to PFOS in groundwater near oxygen sparging wells.

  4. Managed aquifer recharge in Atlantis, South Africa

    CSIR Research Space (South Africa)

    Tredoux, G

    2011-01-01

    Full Text Available , sampling point S8) both calcium and bicarbonate increase to some extent. These changes together with the slight increase in sodium and chloride are ascribed to the dissolution of calcium carbonate from the aquifer and blending with slightly more saline..., magnesium, and particularly bicarbonate are significantly lower (S11) and the composition remains the same after chlorination (S12). During use in the town the sodium, chloride and sulphate concentrations increase notably when considering the treated...

  5. Groundwater resource evaluation of urban Bulawayo aquifer ...

    African Journals Online (AJOL)

    The investigations indicate that the aquifer is unconfined with hydraulic conductivity and specific yield ranging from 0.1 m/d to 2.09 m/d and 0.02 to 0.11, respectively. Recharge estimates indicate an annual recharge of 105.5 mm with 38.4%, 52.1% and 9.5% accounting respectively for direct recharge, water mains and ...

  6. Remedial action and waste disposal project -- 300-FF-1 remedial action readiness assessment plan

    International Nuclear Information System (INIS)

    April, J.G.; Carlson, R.A.; Greif, A.A.; Johnson, C.R.; Orewiler, R.I.; Perry, D.M.; Plastino, J.C.; Roeck, F.V.; Tuttle, B.G.

    1997-04-01

    This Readiness Assessment Plan presents the methodology used to assess the readiness of the 300-FF-1 Remedial Action Project. Remediation involves the excavation, treatment if applicable, and final disposal of contaminated soil and debris associated with the waste sites in the 300-FF-1 Operable Unit. The scope of the 300-FF-1 remediation is to excavate, transport, and dispose of contaminated solid from sites identified in the 300-FF-1 Operable Unit

  7. Compliance monitoring for remediated sites

    International Nuclear Information System (INIS)

    1999-10-01

    Throughout the world, many countries have experienced problems associated with pollution of the environment. Poorly managed practices in nuclear fuel cycle, medicine, industry, weapons production and testing, research and development activities, as well as accidents, and poor disposal practices have produced a large array of radioactively contaminated facilities and sites. Structures, biota, soils, rocks, and both surface and groundwaters have become contaminated with radionuclides and other associated contaminants, a condition that raises serious concern due to potential health effects to the exposed human populations and the environment. In response to the needs of its Member States in dealing with the problems of radioactive contamination in the environment, the IAEA has established an Environmental Restoration Project. The principal aspects of current IAEA efforts in this area include (1) gathering information and data, performing analyses, and publishing technical summaries, and other documents on key technical aspects of environmental restoration; (2) conducting a Co-ordinated Research Project on Environmental Restoration; and (3) providing direct technical assistance to Member States through technical co-operation programmes. The transfer of technologies to Member States in need of applicable methodologies and techniques for the remediation of contaminated sites is a principal objective of this project

  8. Imagery mnemonics and memory remediation.

    Science.gov (United States)

    Richardson, J T

    1992-02-01

    This paper evaluates the claim that imagery mnemonic techniques are useful in remediation of memory disorders in brain-damaged patients. Clinical research has confirmed that such techniques can lead to improved performance on formal testing in a number of neurologic disease populations and following lesions of either the left or right hemisphere. However, those patients with more severe forms of amnesia and those with medial or bilateral damage do not improve unless the learning task is highly structured. Even among patients who show improvement on formal testing, there is little evidence that they maintain the use of these techniques in similar learning tasks or generalize the use to new learning situations. Imagery mnemonics also appear to be of little practical value in the daily activities that are of most concern to brain-damaged patients themselves. The effectiveness of imagery mnemonics appears to depend upon the patients' motivation and insight rather than upon their intelligence or educational level. Instead of training patients in specific mnemonic techniques, clinicians should promote the development of "meta-cognitive" skills and the acquisition of knowledge about domains of practical significance.

  9. Innovative vitrification for soil remediation

    International Nuclear Information System (INIS)

    Jetta, N.W.; Patten, J.S.; Hnat, J.G.

    1995-01-01

    The objective of this DOE demonstration program is to validate the performance and operation of the Vortec Cyclone Melting System (CMS trademark) for the processing of LLW contaminated soils found at DOE sites. This DOE vitrification demonstration project has successfully progressed through the first two phases. Phase I consisted of pilot scale testing with surrogate wastes and the conceptual design of a process plant operating at a generic DOE site. The objective of Phase 2, which is scheduled to be completed the end of FY 95, is to develop a definitive process plant design for the treatment of wastes at a specific DOE facility. During Phase 2, a site specific design was developed for the processing of LLW soils and muds containing TSCA organics and RCRA metal contaminants. Phase 3 will consist of a full scale demonstration at the DOE gaseous diffusion plant located in Paducah, KY. Several DOE sites were evaluated for potential application of the technology. Paducah was selected for the demonstration program because of their urgent waste remediation needs as well as their strong management and cost sharing financial support for the project

  10. New technologies in soil remediation

    Energy Technology Data Exchange (ETDEWEB)

    McAdams, C.L.

    1994-05-01

    If it's not clean, you don't pay.'' That's what Bill Packer, CEO of Seaview Thermal Systems (Seaview, Blue Bell, Pa.) told his first customer when they signed a $27-million contract for the remediation of contaminated soil located at a former town gas plant site at Paterson, N.J. For more than a 100 years, the Public Service Electric and Gas Co. (PSE G), and its predecessors, manufactured methane gas from coal and oil in Paterson on the banks of the Passaic River. Now, under orders from the state to clean up the abandoned, 13-acre site, PSE G has contracted with Seaview. The process Seaview uses -- HT-6 high-temperature thermal desorption -- heats up polluted dirt or other solids up to 2,000 F in a nitrogen atmosphere, and recovers the pollutants for recycling. According to Seaview, in hazardous waste sites with soils contaminated with volatile organic compounds (VOCs), polychlorinated biphenyls (PCBs), or heavy metals, the result is: soil that is 99.99% free of organics and ready to be backfilled, clean water that can be used to remoisturize the soil before backfilling, and oil ready for recycling.

  11. Kerr Hollow Quarry Remediation Project

    International Nuclear Information System (INIS)

    Walker, K.L.

    1993-01-01

    The Kerr Hollow Quarry is a 3-acre flooded limestone quarry located near the Y-12 Facility on the Oak Ridge Reservation. The quarry was used in the 1940s as a source of construction material for the Department of Energy in Oak Ridge, Tennessee. Its use was discontinued in the early 1950s, and it was allowed to flood with water. The quarry presently has a maximum water depth of approximately 55 ft. During the period between the early 1950s until about 1988, the quarry was used for the treatment and disposal of a variety of materials including water-reactive, alkali metals, shock-sensitive chemicals, and compressed gas cylinders. For some of these materials, the treatment consisted of dropping the vessels containing the materials into the quarry from a high bluff located on one side of the quarry. The vessels were then punctured by gun shot, and the materials were allowed to react with the water and sink to the bottom of the quarry. Very few disposal records exist for the period from 1952 to 1962. The records after that time, from 1962 until 1988, indicate some 50 t of hazardous and nonhazardous materials were disposed of in the quarry. This report documents remediation efforts that have taken place at the quarry beginning in September 1990

  12. REAL TIME DATA FOR REMEDIATION ACTIVITIES [11505

    Energy Technology Data Exchange (ETDEWEB)

    BROCK CT

    2011-01-13

    Health physicists from the CH2M HILL Plateau Remediation Company collaborated with Berkeley Nucleonics Corporation to modify the SAM 940 isotope identifier instrument to be used for nuclear waste remediation. These modifications coupled with existing capabilities of the SAM 940 have proven to be invaluable during remediation activities, reducing disposal costs by allowing swift remediation of targeted areas that have been identified as having isotopes of concern (IOC), and eliminating multiple visits to sites by declaring an excavation site clear of IOCs before demobilizing from the site. These advantages are enabled by accumulating spectral data for specific isotopes that is nearly 100 percent free of false positives, which are filtered out in 'real time.'

  13. Nanotechnology for Site Remediation: Fact Sheet

    Science.gov (United States)

    This fact sheet presents a snapshot of nanotechnology and its current uses in remediation. It presents information to help site project managers understand the potential applications of this group of technologies at their sites.

  14. Green PCB Remediation from Sediment Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPRSS technology is an in situ remediation technique for PCB-contaminated sediments. The technique provides an effective and safe method for sediment cleanup...

  15. List of Contractors to Support Anthrax Remediation

    Energy Technology Data Exchange (ETDEWEB)

    Judd, Kathleen S.; Lesperance, Ann M.

    2010-05-14

    This document responds to a need identified by private sector businesses for information on contractors that may be qualified to support building remediation efforts following a wide-area anthrax release.

  16. Civil Remedies Division Administrative Law Judge Decisions

    Data.gov (United States)

    U.S. Department of Health & Human Services — Decisions issued by Administrative Law Judges of the Departmental Appeals Board's Civil Remedies Division concerning fraud and abuse determinations by the Office of...

  17. Libra: An Interdisciplinary Approach to Remediation

    Science.gov (United States)

    Fisher, Dexter; Lamdin, Lois

    1974-01-01

    Describes a program at a community college in Bronx, New York in which English instructors and content area teachers work together to improve the writing of students needing remedial instruction. (RB)

  18. Phytoremediation potential of willow tress for aquifers contaminated with ethanol-blended gasoline

    Energy Technology Data Exchange (ETDEWEB)

    Corseuil, H.X. [Universidade Federal de Santa Catarina, Florianopolis (Brazil). Departamento de Engenharia Sanitaria e Ambiental; Moreno, F.N. [Universidade do Sul de Santa Catarina, Palhoca (Brazil). Centro de Ciencias Agrarias e das Engenharias

    2001-07-01

    Ethanol-blended gasoline has been used in Brazil for 20 years and, probably, is going to be more widely used in North America due to the MtBE environmental effects on groundwater. The potential impacts caused by the presence of ethanol in UST spills are related to the co-solvency effect and the preferential degradation of ethanol over the BTEX compounds. These interactions may increase the length of dissolved hydrocarbon plumes and the costs associated with site remediation. This study investigates the advantages of phytoremediation to overcome the problems associated with the presence of ethanol in groundwater contaminated with gasoline-ethanol mixtures. Experiments were performed under lab conditions with cuttings of Willow tree (Salix babylonica) cultivated hydroponically. Results showed that the cuttings were able to reduce ethanol and benzene concentrations by more than 99% in less than a week. The uptake of both contaminants was confirmed by blank controls and was significantly related to cuttings transpiration capacity. Sorption onto roots biomass also markedly affected the behavior of contaminants in solution. Experiments to evaluate plants' toxicity to ethanol indicated that plants were only affected when aqueous ethanol concentration reached 2000mgl{sup -1}. Results suggest that phytoremediation can be a good complement to intrinsic remediation in shallow aquifer sites contaminated with ethanol-blended gasoline spills. (Author)

  19. 29 CFR 35.40 - Exhaustion of administrative remedies.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 1 2010-07-01 2010-07-01 true Exhaustion of administrative remedies. 35.40 Section 35.40... Enforcement Procedures § 35.40 Exhaustion of administrative remedies. (a) A complainant may file a civil action under the Act following the exhaustion of administrative remedies. Administrative remedies are...

  20. 46 CFR 298.41 - Remedies after default.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Remedies after default. 298.41 Section 298.41 Shipping... Defaults and Remedies, Reporting Requirements, Applicability of Regulations § 298.41 Remedies after default... governing remedies after a default, which relate to our rights and duties, the rights and duties of the...

  1. Remediation of sites with dispersed radioactive contamination

    International Nuclear Information System (INIS)

    2004-01-01

    To respond to the needs of Member States, the IAEA launched an environmental remediation project to deal with the problems of radioactive contamination worldwide. The IAEA environmental remediation project includes an IAEA Coordinated Research Project, as well as the participation of IAEA experts in concrete remediation projects when requested by individual Member States. The IAEA has prepared several documents dedicated to particular technical or conceptual areas, including documents on the characterization of contaminated sites, technical and non-technical factors relevant to the selection of a preferred remediation strategy and technique, overview of applicable techniques for environmental remediation,, options for the cleanup of contaminated groundwater and planning and management issues. In addition, a number of other IAEA publications dealing with related aspects have been compiled under different IAEA projects; these include TECDOCs on the remediation of uranium mill tailings, the decontamination of buildings and roads and the characterization of decommissioned sites. Detailed procedures for the planning and implementation of remedial measures have been developed over the past decade or so. A critical element is the characterization of the contamination and of the various environmental compartments in which it is found, in order to be able to evaluate the applicability of remediation techniques. The chemical or mineralogical form of the contaminant will critically influence the efficiency of the remediation technique chosen. Careful delineation of the contamination will ensure that only those areas or volumes of material that are actually contaminated are treated. This, in turn, reduces the amount of any secondary waste generated. The application of a remediation technique requires holistic studies examining the technical feasibility of the proposed measures, including analyses of their impact. Consequently, input from various scientific and engineering

  2. Waste minimization applications at a remediation site

    International Nuclear Information System (INIS)

    Allmon, L.A.

    1995-01-01

    The Fernald Environmental Management Project (FEMP) owned by the Department of Energy was used for the processing of uranium. In 1989 Fernald suspended production of uranium metals and was placed on the National Priorities List (NPL). The site's mission has changed from one of production to environmental restoration. Many groups necessary for producing a product were deemed irrelevant for remediation work, including Waste Minimization. Waste Minimization does not readily appear to be applicable to remediation work. Environmental remediation is designed to correct adverse impacts to the environment from past operations and generates significant amounts of waste requiring management. The premise of pollution prevention is to avoid waste generation, thus remediation is in direct conflict with this premise. Although greater amounts of waste will be generated during environmental remediation, treatment capacities are not always available and disposal is becoming more difficult and costly. This creates the need for pollution prevention and waste minimization. Applying waste minimization principles at a remediation site is an enormous challenge. If the remediation site is also radiologically contaminated it is even a bigger challenge. Innovative techniques and ideas must be utilized to achieve reductions in the amount of waste that must be managed or dispositioned. At Fernald the waste minimization paradigm was shifted from focusing efforts on source reduction to focusing efforts on recycle/reuse by inverting the EPA waste management hierarchy. A fundamental difference at remediation sites is that source reduction has limited applicability to legacy wastes but can be applied successfully on secondary waste generation. The bulk of measurable waste reduction will be achieved by the recycle/reuse of primary wastes and by segregation and decontamination of secondary wastestreams. Each effort must be measured in terms of being economically and ecologically beneficial

  3. International experience in tailings pond remediation

    International Nuclear Information System (INIS)

    Robertson, A.MacG.

    2001-01-01

    Tailings pond remediation is required primarily on mine closure. While mining is an ancient industry, requirement for mine facility remediation is a comparatively new development. Requirement for remediation has come about partly as a result of mans awareness of the environmental impacts of mining and his desire to minimize this, partly, as a result of the ever-increasing scale and production rates of tailings generation and the resulting increased environmental impacts and safety risks. The paper starts with a review of the evolution of mans intolerance of environmental impacts from tailings production and the assignment of liability to remediate such impacts. Many of the tailings ponds currently undergoing remediation were designed and constructed using methods and technology that would be considered inappropriate for new impoundments being designed and developed today. The paper reviews the history of tailings impoundment design and construction practice and the resulting inherent deficiencies that must be remediated. Current practices and future trends in tailings pond remediation are reviewed. The evolution of regulatory requirements is not only in terms of technical and safety criteria, but also in terms of financial and political risk. Perhaps the most substantive driver of risk management is today the requirement for corporate governance at mining company board level and oversight of new project development in the underdeveloped countries by the large financial institutions responsible for funding projects. Embarrassment in the public eye and punishment in the stock markets for poor environmental and safety performance is driving the need for efficient and effective risk management of potential impacts and the remediation to avoid these. A basis for practical risk management is described. (orig.)

  4. New technologies in decommissioning and remediation

    International Nuclear Information System (INIS)

    Fournier, Vincent

    2016-01-01

    New and emerging technologies are making decommissioning and remediation more cost effective, faster and safer. From planning to execution and control, the use of new technologies is on the rise. Before starting decommissioning or environmental remediation, experts need to plan each step of the process, and to do that, they first need a clear idea of the characteristics of the structure and the level of radiation that they can expect to encounter

  5. Water as a Reagent for Soil Remediation

    Energy Technology Data Exchange (ETDEWEB)

    Jayaweera, Indira S.; Marti-Perez, Montserrat; Diaz-Ferrero, Jordi; Sanjurjo, Angel

    2003-03-06

    SRI International conducted experiments in a two-year, two-phase process to develop and evaluate hydrothermal extraction technology, also known as hot water extraction (HWE) technology, for remediating petroleum-contaminated soils. The bench-scale demonstration of the process has shown great promise, and the implementation of this technology will revolutionize the conventional use of water in soil remediation technologies and provide a standalone technology for removal of both volatile and heavy components from contaminated soil.

  6. Recharge and Aquifer Response: Manukan Island’s Aquifer, Sabah, Malaysia

    Directory of Open Access Journals (Sweden)

    Sarva Mangala Praveena

    2010-01-01

    Full Text Available Manukan Island is a small island located in North-West of Sabah, Malaysia was used as a case study area for numerical modeling of an aquifer response to recharge and pumping rates. The results in this study present the variations of recharge into the aquifer under the prediction simulations. The recharge rate increases the water level as indicated by hydraulic heads. This shows that it can alter groundwater of Manukan Island which has been suffering from an overexploration in its unconfined the aquifer. The increase in recharge rate (from 600 mm/year to 750 mm/year increases the water level indicated by hydraulic heads. A reduction in pumping rate (from 0.072 m3/day to 0.058 m3/day not only increases the amount of water levels in aquifer but also reduces the supply hence a deficit in supply. The increase in hydraulic heads depends on the percentage reduction of pumping and recharges rates. The well water has 1978.3 mg/L chloride with current pumping (0.072 m3/day and recharge rates (600 mm/year. However, with an increased of recharge rate and current pumping rate it has decreased about 1.13%. In addition, reduction in pumping rate made the chloride concentration decreased about 2.8%. In general, a reduction in pumping with an increase in recharge rate leads to a decreased in chloride concentrations within the vicinity of cone of depression. Next, to further develop the numerical model, the model should focus on climate change variables such as consequences of climate change are increase in air temperature, increase in sea surface temperature, and more extreme weather conditions. These parameters are considered critical parameters for climate change impact modeling in aquifers. The behavior of the aquifer and its sustainable pumping rate can be done by applying a computer modeling component.

  7. Management of aquifer recharge in Lebanon by removing seawater intrusion from coastal aquifers.

    Science.gov (United States)

    Masciopinto, Costantino

    2013-11-30

    This study investigates the feasibility of management of aquifer recharge (MAR) in Lebanon by designing well barriers to remove seawater intrusion from the fractured carbonate aquifers. Groundwater flow and saltwater/freshwater 50% sharp interface have been modeled along the coastal area using the Ghyben-Herzberg theory. The groundwater flow simulations have been supported by field transmissivity estimations and depth measurements carried out on 44 wells during 2003. Results have shown the seawater intrusion in coastal aquifers at Jieh and Damour regions. Three well-injection barriers have been proposed. The water volumes for recharge and the barrier positions have been defined by means of groundwater flow simulations. MAR can provide a valuable contribution to colloid (even pathogen) removal from injectant water, although during water infiltration in subsoil the reduction of aquifer permeability causes clogging. A simple new model for estimating the soil-rock permeability reduction due to the well clogging has been presented. The MAR, including the soil aquifer treatment at Damour and Jieh regions, has been studied by considering aquifer transmissivity (and soil porosity) reduction caused by clogging. Furthermore, the appropriate mixing of the injectant water by using reclaimed water, groundwater and surface water can be simulated using the proposed models. The time required to achieve 5% of rock permeability reduction at the proposed well barriers ranged from 71 to 935 d, by changing water quality and flow rate for recharge. This study can assist regional governments with water management in areas affected by scarcity of freshwater by implementing appropriate well-barrier projects. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Operable Unit 3-13, Group 3, Other Surface Soils Remediation Sets 4-6 (Phase II) Remedial Design/Remedial Action Work Plan

    Energy Technology Data Exchange (ETDEWEB)

    D. E. Shanklin

    2006-06-01

    This Remedial Design/Remedial Action Work Plan provides the framework for defining the remedial design requirements, preparing the design documentation, and defining the remedial actions for Waste Area Group 3, Operable Unit 3-13, Group 3, Other Surface Soils, Remediation Sets 4-6 (Phase II) located at the Idaho Nuclear Technology and Engineering Center at the Idaho National Laboratory. This plan details the design developed to support the remediation and disposal activities selected in the Final Operable Unit 3-13, Record of Decision.

  9. Stability of Cr Remediation Products Linked to Duration of Bioremediation.

    Science.gov (United States)

    Miller, L. G.; Bobb, C.; Bennett, S.; Izbicki, J. A.

    2017-12-01

    Groundwater and alluvium beneath Hinkley Valley, Mojave Desert, California contain elevated levels of anthropogenic Cr(VI). In-situ remediation (ISR) using ethanol as an electron donor is employed at the site to reduce soluble, toxic, Cr(VI) to insoluble and non-hazardous Cr(III). We conducted year-long experiments to determine the fate of isotopically-labeled 50Cr tracer within microcosms consisting of sealed batch reactors containing aquifer material and groundwater from within and near the mapped Cr(VI) plume. Ethanol was added periodically to the reactors to drive biologically mediated reduction of Cr(VI). Reduction and sorption of 50Cr tracer on the solid matrix was examined by selective extractions designed to monitor operationally-defined weakly sorbed, specifically sorbed, amorphous, and well-crystalized strong-acid extractable phases. Recovery of the 50Cr tracer by ICP-MS analysis of each extract revealed the degree of mineralization of the added 50Cr. Initially, the tracer was distributed evenly between the aqueous and weakly sorbed phases, with little present in the strongly sorbed, amorphous or crystalline phases. After several months, most 50Cr was incorporated within the amorphous fraction and by one year increasing amounts were associated with the crystalline phase. Artificial substrates also were prepared as experimental controls. Artificial substrates showed similar trends; however less 50Cr was associated with amorphous Fe in acid-washed Ottowa sand coated with 2-line ferrihydrite than in aquifer sediments. Washed sand without ferrihydrite reacted with site water sorbed very little 50Cr, and no 50Cr was found in the amorphous fraction; however some was converted to the crystalline form with time. This suggests that groundwater-borne organisms alone were capable of reducing Cr(VI) to Cr(III) with ethanol in the absence of Fe(II). A planned metagenomics study of materials from these experiments is expected to highlight changes in microbial community

  10. Nuclear facility decommissioning and site remedial actions

    Energy Technology Data Exchange (ETDEWEB)

    Owen, P.T.; Knox, N.P.; Ferguson, S.D.; Fielden, J.M.; Schumann, P.L.

    1989-09-01

    The 576 abstracted references on nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the tenth in a series of reports prepared annually for the US Department of Energy's Remedial Action Programs. Citations to foreign and domestic literature of all types--technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions--have been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy's Remedial Action Programs. Major sections are (1) Surplus Facilities Management Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Program, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Uranium Mill Tailings Management, (7) Technical Measurements Center, and (8) General Remedial Action Program Studies. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication description. Indexes are provided for author, corporate affiliation, title work, publication description, geographic location, subject category, and keywords.

  11. Hanford sitewide grounwater remediation - supporting technical information

    International Nuclear Information System (INIS)

    Chiaramonte, G.R.

    1996-05-01

    The Hanford Sitewide Groundwater Remediation Strategy was issued in 1995 to establish overall goals for groundwater remediation on the Hanford Site. This strategy is being refined to provide more detailed justification for remediation of specific plumes and to provide a decision process for long-range planning of remediation activities. Supporting this work is a comprehensive modeling study to predict movement of the major site plumes over the next 200 years to help plan the remediation efforts. The information resulting from these studies will be documented in a revision to the Strategy and the Hanford Site Groundwater Protection Management Plan. To support the modeling work and other studies being performed to refine the strategy, this supporting technical information report has been produced to compile all of the relevant technical information collected to date on the Hanford Site groundwater contaminant plumes. The primary information in the report relates to conceptualization of the source terms and available history of groundwater transport, and description of the contaminant plumes. The primary information in the report relates to conceptualization of the source terms and available history of groundwater transport, description of the contaminant plumes, rate of movement based on the conceptual model and monitoring data, risk assessment, treatability study information, and current approach for plume remediation

  12. Hazardous waste treatment and environmental remediation research

    International Nuclear Information System (INIS)

    1989-01-01

    Los Alamos National Laboratory (LANL) is currently evaluating hazardous waste treatment and environmental remediation technologies in existence and under development to determine applicability to remediation needs of the DOE facilities under the Albuquerque Operations Office and to determine areas of research need. To assist LANL is this effort, Science Applications International Corporation (SAIC) conducted an assessment of technologies and monitoring methods that have been demonstrated or are under development. The focus of this assessment is to: (1) identify existing technologies for hazardous waste treatment and environmental remediation of old waste sites; (2) identify technologies under development and the status of the technology; (3) assess new technologies that need development to provide adequate hazardous waste treatment and remedial action technologies for DOD and DOE sites; and (4) identify hazardous waste and remediation problems for environmental research and development. There are currently numerous research and development activities underway nationwide relating to environmental contaminants and the remediation of waste sites. To perform this effort, SAIC evaluated current technologies and monitoring methods development programs in EPA, DOD, and DOE, as these are the primary agencies through which developmental methods are being demonstrated. This report presents this evaluation and provides recommendations as to pertinent research needs or activities to address waste site contamination problems. The review and assessment have been conducted at a programmatic level; site-specific and contaminant-specific evaluations are being performed by LANL staff as a separate, related activity

  13. Nuclear facility decommissioning and site remedial actions

    International Nuclear Information System (INIS)

    Owen, P.T.; Knox, N.P.; Ferguson, S.D.; Fielden, J.M.; Schumann, P.L.

    1989-09-01

    The 576 abstracted references on nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the tenth in a series of reports prepared annually for the US Department of Energy's Remedial Action Programs. Citations to foreign and domestic literature of all types--technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions--have been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy's Remedial Action Programs. Major sections are (1) Surplus Facilities Management Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Program, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Uranium Mill Tailings Management, (7) Technical Measurements Center, and (8) General Remedial Action Program Studies. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication description. Indexes are provided for author, corporate affiliation, title work, publication description, geographic location, subject category, and keywords

  14. Characteristics of Southern California coastal aquifer systems

    Science.gov (United States)

    Edwards, B.D.; Hanson, R.T.; Reichard, E.G.; Johnson, T.A.

    2009-01-01

    Most groundwater produced within coastal Southern California occurs within three main types of siliciclastic basins: (1) deep (>600 m), elongate basins of the Transverse Ranges Physiographic Province, where basin axes and related fluvial systems strike parallel to tectonic structure, (2) deep (>6000 m), broad basins of the Los Angeles and Orange County coastal plains in the northern part of the Peninsular Ranges Physiographic Province, where fluvial systems cut across tectonic structure at high angles, and (3) shallow (75-350 m), relatively narrow fluvial valleys of the generally mountainous southern part of the Peninsular Ranges Physiographic Province in San Diego County. Groundwater pumped for agricultural, industrial, municipal, and private use from coastal aquifers within these basins increased with population growth since the mid-1850s. Despite a significant influx of imported water into the region in recent times, groundwater, although reduced as a component of total consumption, still constitutes a significant component of water supply. Historically, overdraft from the aquifers has caused land surface subsidence, flow between water basins with related migration of groundwater contaminants, as well as seawater intrusion into many shallow coastal aquifers. Although these effects have impacted water quality, most basins, particularly those with deeper aquifer systems, meet or exceed state and national primary and secondary drinking water standards. Municipalities, academicians, and local water and governmental agencies have studied the stratigraphy of these basins intensely since the early 1900s with the goals of understanding and better managing the important groundwater resource. Lack of a coordinated effort, due in part to jurisdictional issues, combined with the application of lithostratigraphic correlation techniques (based primarily on well cuttings coupled with limited borehole geophysics) have produced an often confusing, and occasionally conflicting

  15. Development of mathematical models for insitu bioremediation of Cr(VI) contaminated Aquifers

    Science.gov (United States)

    Vairavan, S.; Philip, L.; Bhallamudi, M. S.

    2009-12-01

    Hexavalent Chromium (Cr(VI)) is a contaminant of significant concern due to its carcinogenic and mutagenic property in mammals. Cr(VI) abatement in aquifers can be achieved by reducing chromium from its hexavalent state to trivalent state because Cr(III) is less toxic, insoluble and immobile compared to Cr(VI). Reduction of Cr(VI) by Fe(II)/S2- present in mineral deposits followed by precipitation as hydroxides and/or sulfides and adsorption of Cr(VI) over mineral deposits in the geological formations are predominant mechanisms which account for the natural attenuation of Cr(VI) inside an aquifer. Once the Cr(VI) concentration goes beyond the carrying capacity of the aquifer, it can be cleaned by constructing a Permeable Reactive Barrier (PRB) perpendicular to the direction of the flow of groundwater or by introducing Injection Wells (IW) along the direction of flow. In both the above mentioned cases addition of chemical reductants results in high costs. On the other hand, bacterial biotransformation of Cr(VI) in presence of organic matter seems to be a viable and eco friendly option for remediation of chromium contaminated aquifers. Enhancement of biotransformation of hexavalent chromium is expected in the presence of soil microbes such as Sulfate Reducing Bacteria (SRB) and Iron Reducing Bacteria (IRB) along with Chromium Reducing Bacteria (CRB). Groundwater usually contains sulfate and iron (dissolution from the mineral deposits) which can act as electron acceptor for IRB and SRB metabolism and yield biogenic reductants such as Fe2+, and S2- which abiotically reduce Cr(VI) to Cr(III). The objective of the present work is to understand the effect of different electron acceptors on Cr(VI) reduction and to model the fate and transport of Cr(VI) in an aquifer. Batch studies were conducted to estimate biokinetic parameters such as maximum specific growth rate (µmax), half saturation constant (Ks), yield coefficient (YT) and inhibition constant (Ki). Transformation

  16. Hydrogeology - MO 2014 Thermoclines Springfield Plateau Aquifer (SHP)

    Data.gov (United States)

    NSGIC State | GIS Inventory — Springfield Plateau aquifer thermo cline correlates the temperature data throughout the state in the upper Mississippian Subsystem, from the Ste. Genevieve Limestone...

  17. Sealable joint steel sheet piling for groundwater control and remediation: Case histories

    International Nuclear Information System (INIS)

    Smyth, D.; Jowett, R.; Gamble, M.

    1997-01-01

    The Waterloo Barrier trademark steel sheet piling (patents pending) incorporates a cavity at each interlocking joint that is flushed clean and injected with sealant after the piles have been driven into the ground to form a vertical cutoff wall. The installation and sealing procedures allow for a high degree of quality assurance and control. Bulk wall hydraulic conductivities of 10 -8 to 10 -10 cm/sec have been demonstrated at field installations. Recent case histories are presented in which Waterloo Barrier trademark cutoff walls are used to prevent off-site migration of contaminated groundwater or soil gases to adjacent property and waterways. Full enclosures to isolate DNAPL source zones or portions of contaminated aquifers for pilot-scale remediation testing will also be described. Monitoring data will be used to demonstrate the effectiveness of the Waterloo Barrier trademark in these applications

  18. Waste management facility remediation and decommissioning at a national nuclear research site

    International Nuclear Information System (INIS)

    Cameron, D.J.; Dolinar, G.M.; Killey, R.W.D.

    1994-01-01

    Historic waste management practices at eight locations on AECL's Chalk River site have resulted in the formation of contaminated groundwater plumes, some of which have surfaced and contaminated surface materials. A priority setting process has been used to establish a plan of attack that will lead to the eventual decommissioning of these facilities. In general terms, the preferred approach is to install impermeable covers to prevent further leaching of waste sources and to prevent escape of leachate to the biosphere, followed by cleanup of surface contamination and remediation of aquifers. Final disposal of the waste sources would be delayed for perhaps 20 years. Substantial progress has been made in the treatment of contaminated groundwater, with one field installation in place and another under development. This paper describes how the prioritization task was tackled to produce a long term plan of action and describes initial interventions that have been attempted and their results. 4 refs., 3 tabs., 3 figs

  19. Straddle-packer aquifer test analyses of the Snake River Plain aquifer at the Idaho National Engineering Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, G.S.; Frederick, D.B.

    1997-01-01

    The State of Idaho INEL Oversight Program, with the University of Idaho, Idaho State University, Boise State University, and the Idaho Geologic Survey, used a straddle-packer system to investigate vertical variations in characteristics of the Snake River Plain aquifer at the Idaho National Engineering Laboratory in southeast Idaho. Sixteen single-well aquifer tests were conducted on.isolated intervals in three observation wells. Each of these wells has approximately 200 feet of open borehole below the water table, penetrating the E through G and I basalt flow groups and interbedded sediments of the Snake River Plain aquifer. The success of the aquifer tests was limited by the inability to induce measurable drawdown in several zones. Time-drawdown data from aquifer tests were matched to type curves for 8 of the 16 zones tested. A single aquifer test at the water table exhibited greater curvature than those at depth. The increased degree of curvature suggests an unconfined response and resulted in an estimate of specific yield of 0.03. Aquifer tests below the water table generally yielded time-drawdown graphs with a rapid initial response followed by constant drawdown throughout the duration of the tests; up to several hours in length. The rapid initial response implies that the aquifer responds as a confined system during brief pumping periods. The nearly constant drawdown suggests a secondary source of water, probably vertical flow from overlying and underlying aquifer layers. Three analytical models were applied for comparison to the conceptual model and to provide estimates of aquifer properties. This, Hantush-Jacob leaky aquifer, and the Moench double-porosity fractured rock models were fit to time-drawdown data. The leaky aquifer type curves of Hantush and Jacob generally provided the best match to observed drawdown. A specific capacity regression equation was also used to estimate hydraulic conductivity.

  20. Straddle-packer aquifer test analyses of the Snake River Plain aquifer at the Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Johnson, G.S.; Frederick, D.B.

    1997-01-01

    The State of Idaho INEL Oversight Program, with the University of Idaho, Idaho State University, Boise State University, and the Idaho Geologic Survey, used a straddle-packer system to investigate vertical variations in characteristics of the Snake River Plain aquifer at the Idaho National Engineering Laboratory in southeast Idaho. Sixteen single-well aquifer tests were conducted on.isolated intervals in three observation wells. Each of these wells has approximately 200 feet of open borehole below the water table, penetrating the E through G and I basalt flow groups and interbedded sediments of the Snake River Plain aquifer. The success of the aquifer tests was limited by the inability to induce measurable drawdown in several zones. Time-drawdown data from aquifer tests were matched to type curves for 8 of the 16 zones tested. A single aquifer test at the water table exhibited greater curvature than those at depth. The increased degree of curvature suggests an unconfined response and resulted in an estimate of specific yield of 0.03. Aquifer tests below the water table generally yielded time-drawdown graphs with a rapid initial response followed by constant drawdown throughout the duration of the tests; up to several hours in length. The rapid initial response implies that the aquifer responds as a confined system during brief pumping periods. The nearly constant drawdown suggests a secondary source of water, probably vertical flow from overlying and underlying aquifer layers. Three analytical models were applied for comparison to the conceptual model and to provide estimates of aquifer properties. This, Hantush-Jacob leaky aquifer, and the Moench double-porosity fractured rock models were fit to time-drawdown data. The leaky aquifer type curves of Hantush and Jacob generally provided the best match to observed drawdown. A specific capacity regression equation was also used to estimate hydraulic conductivity

  1. Magnetic separation for environmental remediation

    International Nuclear Information System (INIS)

    Schake, A.R.; Avens, L.R.; Hill, D.D.; Padilla, D.D.; Prenger, F.C.; Romero, D.A.; Worl, L.A.; Tolt, T.L.

    1994-01-01

    High Gradient Magnetic Separation (HGMS) is a form of magnetic separation used to separate solids from other solids, liquids or gases. HGMS uses large magnetic field gradients to separate ferromagnetic and paramagnetic particles from diamagnetic host materials. The technology relies only on physical properties, and therefore separations can be achieved while producing a minimum of secondary waste. Actinide and fission product wastes within the DOE weapons complex pose challenging problems for environmental remediation. Because the majority of actinide complexes and many fission products are paramagnetic, while most host materials are diamagnetic, HGMS can be used to concentrate the contaminants into a low volume waste stream. The authors are currently developing HGMS for applications to soil decontamination, liquid waste treatment, underground storage tank waste treatment, and actinide chemical processing residue concentration. Application of HGMS usually involves passing a slurry of the contaminated mixture through a magnetized volume. Field gradients are produced in the magnetized volume by a ferromagnetic matrix material, such as steel wool, expanded metal, iron shot, or nickel foam. The matrix fibers become trapping sites for ferromagnetic and paramagnetic particles in the host material. The particles with a positive susceptibility are attracted toward an increasing magnetic field gradient and can be extracted from diamagnetic particles, which react in the opposite direction, moving away from the areas of high field gradients. The extracted paramagnetic contaminants are flushed from the matrix fibers when the magnetic field is reduced to zero or when the matrix canister is removed from the magnetic field. Results are discussed for the removal of uranium trioxide from water, PuO 2 , U, and Pu from various soils (Fernald, Nevada Test Site), and the waste water treatment of Pu and Am isotopes using HGMS

  2. Stochastic analysis of the efficiency of coupled hydraulic-physical barriers to contain solute plumes in highly heterogeneous aquifers

    Science.gov (United States)

    Pedretti, Daniele; Masetti, Marco; Beretta, Giovanni Pietro

    2017-10-01

    The expected long-term efficiency of vertical cutoff walls coupled to pump-and-treat technologies to contain solute plumes in highly heterogeneous aquifers was analyzed. A well-characterized case study in Italy, with a hydrogeological database of 471 results from hydraulic tests performed on the aquifer and the surrounding 2-km-long cement-bentonite (CB) walls, was used to build a conceptual model and assess a representative remediation site adopting coupled technologies. In the studied area, the aquifer hydraulic conductivity Ka [m/d] is log-normally distributed with mean E (Ya) = 0.32 , variance σYa2 = 6.36 (Ya = lnKa) and spatial correlation well described by an exponential isotropic variogram with integral scale less than 1/12 the domain size. The hardened CB wall's hydraulic conductivity, Kw [m/d], displayed strong scaling effects and a lognormal distribution with mean E (Yw) = - 3.43 and σYw2 = 0.53 (Yw =log10Kw). No spatial correlation of Kw was detected. Using this information, conservative transport was simulated across a CB wall in spatially correlated 1-D random Ya fields within a numerical Monte Carlo framework. Multiple scenarios representing different Kw values were tested. A continuous solute source with known concentration and deterministic drains' discharge rates were assumed. The efficiency of the confining system was measured by the probability of exceedance of concentration over a threshold (C∗) at a control section 10 years after the initial solute release. It was found that the stronger the aquifer heterogeneity, the higher the expected efficiency of the confinement system and the lower the likelihood of aquifer pollution. This behavior can be explained because, for the analyzed aquifer conditions, a lower Ka generates more pronounced drawdown in the water table in the proximity of the drain and consequently a higher advective flux towards the confined area, which counteracts diffusive fluxes across the walls. Thus, a higher σYa2 results

  3. Provincial labour market study : mould remediation industry

    International Nuclear Information System (INIS)

    2003-06-01

    Indoor exposure to mold can be problematic to human health, and some molds are considered to be toxigenic. The emergent mold remediation industry in Ontario is fragmented, with various different standards, training and certification processes. This report investigated the labour market for mold remediation workers, with particular reference to training needs and priorities. Research was derived from a literature review in order to analyze the economic, legal, technical and social context of the mold remediation industry. Data on the organized work force were obtained from records of the International Union of Painters and Allied Trades, the Labour Force Historical Review 2002, and various publications. Population data from the Ontario government and Statistics Canada were also used. Surveys of workers and employers were conducted with questionnaires. Results of the surveys indicated that mold remediation projects currently constitute a minority share of most companies' business. However, the importance of mold remediation projects is expected to increase, and industry self-regulation is the most likely scenario for the development of standards and related training programs. It was suggested that the creation of an industry body representing key stakeholder constituencies or the legitimization of an existing industry organization will reduce fragmentation and facilitate research, standard setting and certification, as well as improve marketing and education. If the demand for mold remediation services increases as anticipated, the industry will face the challenge of remaining competitive in the province's projected labour market due to shortages in personnel. There was a strong consensus between employers and workers in the mold remediation industry regarding the need for skills upgrading and compulsory certification. It was concluded that leadership is needed in the development and delivery of training programs, standard setting, recruitment and retention and

  4. Provincial labour market study : mould remediation industry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-06-15

    Indoor exposure to mold can be problematic to human health, and some molds are considered to be toxigenic. The emergent mold remediation industry in Ontario is fragmented, with various different standards, training and certification processes. This report investigated the labour market for mold remediation workers, with particular reference to training needs and priorities. Research was derived from a literature review in order to analyze the economic, legal, technical and social context of the mold remediation industry. Data on the organized work force were obtained from records of the International Union of Painters and Allied Trades, the Labour Force Historical Review 2002, and various publications. Population data from the Ontario government and Statistics Canada were also used. Surveys of workers and employers were conducted with questionnaires. Results of the surveys indicated that mold remediation projects currently constitute a minority share of most companies' business. However, the importance of mold remediation projects is expected to increase, and industry self-regulation is the most likely scenario for the development of standards and related training programs. It was suggested that the creation of an industry body representing key stakeholder constituencies or the legitimization of an existing industry organization will reduce fragmentation and facilitate research, standard setting and certification, as well as improve marketing and education. If the demand for mold remediation services increases as anticipated, the industry will face the challenge of remaining competitive in the province's projected labour market due to shortages in personnel. There was a strong consensus between employers and workers in the mold remediation industry regarding the need for skills upgrading and compulsory certification. It was concluded that leadership is needed in the development and delivery of training programs, standard setting, recruitment and retention

  5. In Situ Remediation Integrated Program: Technology summary

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    The In Situ Remediation Integrated Program (ISR IP) was instituted out of recognition that in situ remediation could fulfill three important criteria: significant cost reduction of cleanup by eliminating or minimizing excavation, transportation, and disposal of wastes; reduced health impacts on workers and the public by minimizing exposure to wastes during excavation and processing; and remediation of inaccessible sites, including: deep subsurfaces, in, under, and around buildings. Buried waste, contaminated soils and groundwater, and containerized wastes are all candidates for in situ remediation. Contaminants include radioactive wastes, volatile and non-volatile organics, heavy metals, nitrates, and explosive materials. The ISR IP intends to facilitate development of in situ remediation technologies for hazardous, radioactive, and mixed wastes in soils, groundwater, and storage tanks. Near-term focus is on containment of the wastes, with treatment receiving greater effort in future years. ISR IP is an applied research and development program broadly addressing known DOE environmental restoration needs. Analysis of a sample of 334 representative sites by the Office of Environmental Restoration has shown how many sites are amenable to in situ remediation: containment--243 sites; manipulation--244 sites; bioremediation--154 sites; and physical/chemical methods--236 sites. This needs assessment is focused on near-term restoration problems (FY93--FY99). Many other remediations will be required in the next century. The major focus of the ISR EP is on the long term development of permanent solutions to these problems. Current needs for interim actions to protect human health and the environment are also being addressed.

  6. In Situ Remediation Integrated Program: Technology summary

    International Nuclear Information System (INIS)

    1994-02-01

    The In Situ Remediation Integrated Program (ISR IP) was instituted out of recognition that in situ remediation could fulfill three important criteria: significant cost reduction of cleanup by eliminating or minimizing excavation, transportation, and disposal of wastes; reduced health impacts on workers and the public by minimizing exposure to wastes during excavation and processing; and remediation of inaccessible sites, including: deep subsurfaces, in, under, and around buildings. Buried waste, contaminated soils and groundwater, and containerized wastes are all candidates for in situ remediation. Contaminants include radioactive wastes, volatile and non-volatile organics, heavy metals, nitrates, and explosive materials. The ISR IP intends to facilitate development of in situ remediation technologies for hazardous, radioactive, and mixed wastes in soils, groundwater, and storage tanks. Near-term focus is on containment of the wastes, with treatment receiving greater effort in future years. ISR IP is an applied research and development program broadly addressing known DOE environmental restoration needs. Analysis of a sample of 334 representative sites by the Office of Environmental Restoration has shown how many sites are amenable to in situ remediation: containment--243 sites; manipulation--244 sites; bioremediation--154 sites; and physical/chemical methods--236 sites. This needs assessment is focused on near-term restoration problems (FY93--FY99). Many other remediations will be required in the next century. The major focus of the ISR EP is on the long term development of permanent solutions to these problems. Current needs for interim actions to protect human health and the environment are also being addressed

  7. 200-UP-1 groundwater remedial design/remedial action work plan. Revision 1

    International Nuclear Information System (INIS)

    1997-07-01

    This 200-UP-1 remedial design report presents the objective and rationale developed for the design and implementation of the selected interim remedial measure for the 200-UP-1 Operable Unit, located in the 200 West Area of the Hanford Site

  8. Remedial action and waste disposal project: 100-DR-1 remedial action readiness evaluation plan

    International Nuclear Information System (INIS)

    April, J.G.; Bryant, D.L.; Calverley, C.

    1996-08-01

    This plan presents the method used to assess the readiness of the 100- DR-1 Remedial Action Project. Remediation of the 100-D sites (located on the Hanford Site) involves the excavation (treatment if applicable) and final disposal of contaminated soil and debris associated with the high-priority waste sites in the 100 Areas

  9. The Aftermath of Remedial Math: Investigating the Low Rate of Certificate Completion among Remedial Math Students

    Science.gov (United States)

    Bahr, Peter Riley

    2013-01-01

    Nationally, a majority of community college students require remedial assistance with mathematics, but comparatively few students who begin the remedial math sequence ultimately complete it and achieve college-level math competency. The academic outcomes of students who begin the sequence but do not complete it are disproportionately unfavorable:…

  10. The impact of aquifer heterogeneity on the performance of aquifer thermal energy storage

    NARCIS (Netherlands)

    Sommer, W.T.; Valstar, J.R.; Gaans, van P.; Grotenhuis, J.T.C.; Rijnaarts, H.

    2013-01-01

    Heterogeneity in hydraulic properties of the subsurface is not accounted for in current design calculations of aquifer thermal energy storage (ATES). However, the subsurface is heterogeneous and thus affects the heat distribution around ATES wells. In this paper, the influence of heterogeneity on

  11. Relationships Between Aquifer Properties and Microbial Populations in the Borden Aquifer

    DEFF Research Database (Denmark)

    Barbaro, Susan Elizabeth; Albrechtsen, Hans-Jørgen; Jensen, Bjorn K.

    1994-01-01

    Microbial numbers and activity were determined for 9 sediment cores 1.5 m in length collected from a shallow sandy aquifer at Canadian Forces Base, Borden, Ontario. Cores were extracted from a pristine Zone 0.5-1.0 m below the water table (1.5-3.0 m below the ground surface). Viable cell counts...

  12. Source, variability, and transformation of nitrate in a regional karst aquifer: Edwards aquifer, central Texas.

    Science.gov (United States)

    Musgrove, MaryLynn; Opsahl, Stephen P.; Mahler, Barbara J.; Herrington, Chris; Sample, Thomas; Banta, John

    2016-01-01

    Many karst regions are undergoing rapid population growth and expansion of urban land accompanied by increases in wastewater generation and changing patterns of nitrate (NO3−) loading to surface and groundwater. We investigate variability and sources of NO3− in a regional karst aquifer system, the Edwards aquifer of central Texas. Samples from streams recharging the aquifer, groundwater wells, and springs were collected during 2008–12 from the Barton Springs and San Antonio segments of the Edwards aquifer and analyzed for nitrogen (N) species concentrations and NO3− stable isotopes (δ15N and δ18O). These data were augmented by historical data collected from 1937 to 2007. NO3− concentrations and discharge data indicate that short-term variability (days to months) in groundwater NO3− concentrations in the Barton Springs segment is controlled by occurrence of individual storms and multi-annual wet-dry cycles, whereas the lack of short-term variability in groundwater in the San Antonio segment indicates the dominance of transport along regional flow paths. In both segments, longer-term increases (years to decades) in NO3− concentrations cannot be attributed to hydrologic conditions; rather, isotopic ratios and land-use change indicate that septic systems and land application of treated wastewater might be the source of increased loading of NO3−. These results highlight the vulnerability of karst aquifers to NO3− contamination from urban wastewater. An analysis of N-species loading in recharge and discharge for the Barton Springs segment during 2008–10 indicates an overall mass balance in total N, but recharge contains higher concentrations of organic N and lower concentrations of NO3−than does discharge, consistent with nitrification of organic N within the aquifer and consumption of dissolved oxygen. This study demonstrates that subaqueous nitrification of organic N in the aquifer, as opposed to in soils, might be a previously

  13. Aquifer thermal energy (heat and chill) storage

    Energy Technology Data Exchange (ETDEWEB)

    Jenne, E.A. (ed.)

    1992-11-01

    As part of the 1992 Intersociety Conversion Engineering Conference, held in San Diego, California, August 3--7, 1992, the Seasonal Thermal Energy Storage Program coordinated five sessions dealing specifically with aquifer thermal energy storage technologies (ATES). Researchers from Sweden, The Netherlands, Germany, Switzerland, Denmark, Canada, and the United States presented papers on a variety of ATES related topics. With special permission from the Society of Automotive Engineers, host society for the 1992 IECEC, these papers are being republished here as a standalone summary of ATES technology status. Individual papers are indexed separately.

  14. Geopressured-geothermal aquifers. Final contract report

    Energy Technology Data Exchange (ETDEWEB)

    1983-08-01

    Task 1 is to provide petrophysical and reservoir analysis of wells drilled into geopressured-geothermal aquifers containing dissolved methane. The list of Design Wells and Wells of Opportunity analyzed: Fairfax Foster Sutter No. 2 (WOO), Pleasant Bayou No. 2 (Design), Amoco Fee No. 1 (Design), G.M. Koelemay No. 1 (WOO), Gladys McCall No. 1 (Design), P.R. Girouard No. 1 (WOO), and Crown Zellerbach No. 2 (WOO). Petrophysical and reservoir analysis of the above wells were performed based on availability of data. The analysis performed on each well, the assumptions made during simulation, and conclusions reached.

  15. SRP baseline hydrogeologic investigation: Aquifer characterization

    Energy Technology Data Exchange (ETDEWEB)

    Strom, R.N.; Kaback, D.S.

    1992-03-31

    An investigation of the mineralogy and chemistry of the principal hydrogeologic units and the geochemistry of the water in the principal aquifers at Savannah River Site (SRS) was undertaken as part of the Baseline Hydrogeologic Investigation. This investigation was conducted to provide background data for future site studies and reports and to provide a site-wide interpretation of the geology and geochemistry of the Coastal Plain Hydrostratigraphic province. Ground water samples were analyzed for major cations and anions, minor and trace elements, gross alpha and beta, tritium, stable isotopes of hydrogen, oxygen, and carbon, and carbon-14. Sediments from the well borings were analyzed for mineralogy and major and minor elements.

  16. Integrated enhanced bioremediation and vacuum extraction for remediation of a hydrocarbon release in response to oscillating hydrologic conditions 'Traverse Co-Bio-Vac'

    International Nuclear Information System (INIS)

    Korreck, W.M.; Armstrong, J.M.; Douglass, R.H.

    1992-01-01

    The use of enhanced in-situ biological treatment and vacuum extraction has been demonstrated to be successful in the remediation of ground water and soil contaminated with hydrocarbons. Seasonal fluctuations in the ground water causes the zone of contamination to be in the either saturated or unsaturated zone of the aquifer. In order to address these conditions, an integrated engineering design approach is being taken for the full scale remediation of an aviation of an aviation gasoline spill at the US Coast Guard Air Station at Traverse City, Township, Michigan. Enhanced aerobic biodegradation will be utilized during the periods of high water table whereby most of the contaminated interval is saturated. Carbon treated water will be utilized from the existing ground water plume. Oxygen will be injected via an oxygen generator to saturate the process stream prior to discharge to the aquifer. During low water table conditions, the same infrastructure will be utilized as a modified vacuum extraction system. The same injection wells used during the high water table would then be used during the low table condition as vapor extraction wells. The vapors will be routed to an above-ground catalytic incinerator for compound destruction. This integrated approach, entitled 'Traverse Co-Bio-Vac,' should reduce the capital costs of installing a full scale remedial system as well allowing the system to operate efficiently depending on water table conditions. The system is expected to be constructed in 1992

  17. Temporal and spatial variations in groundwater quality resulting from policy-induced reductions in nitrate leaching to the Rabis Creek aquifer, Denmark

    Science.gov (United States)

    Jessen, Søren; Engesgaard, Peter; Thorling, Lærke; Müller, Sascha; Leskelä, Jari; Postma, Dieke

    2016-04-01

    Twenty-five years of annual groundwater quality monitoring data from the sandy unconfined Rabis Creek aquifer were used to assess the effects of political actions aimed to reduce nitrate leaching to the aquifer. Data were collected from eight multilevel samplers along a ˜3 km transect, which follows the general direction of groundwater flow. Each multilevel sampler comprises 20 screens placed with a 1 m vertical distance from near the water table downwards. The transect covers areas of livestock, plantation & heath, and agriculture. The history of nitrate leaching to the aquifer was assessed using data from screens close to the water table of multilevel samplers placed within agricultural areas. According to these data, nitrate concentrations of infiltrating 'agricultural' water peaked at 2-3 mM (120-180 mg/L) in the year 1989, and then gradually decreased and stabilized at 0.25-1.0 mM (15-60 mg/L) from year 2000. Local farmers declare having used the maximum fertilization rate allowed during the period. The timing of the observed decrease therefore suggests a direct link to the political action plans implemented in the same period. Parallel to the development in nitrate leaching, although with a transport time lag, the average concentration of nitrate in the oxic zone of the aquifer was roughly halved between 2000 and 2013. As a response to political initiatives of the late 1980'ies, part of the area covering the aquifer was changed from agriculture to non-fertilized grass for livestock; the data shows that this effectively remediated the aquifer underneath in less than 20 years, to become nitrate-free and attain background sulfate levels. The oxidized and pyritic reduced zone of the aquifer is separated by a <1 m redoxcline. Denitrification by the pyrite releases sulfate that is retained down-gradient as a tracer for historical nitrate loading to the aquifer. Thus sulfate concentrations currently increase in the multilevel samplers positioned furthest down

  18. The usefulness of multi-well aquifer tests in heterogeneous aquifers

    International Nuclear Information System (INIS)

    Young, S.C.; Benton, D.J.; Herweijer, J.C.; Sims, P.

    1990-01-01

    Three large-scale (100 m) and seven small-scale (3-7 m) multi-well aquifer tests were conducted in a heterogeneous aquifer to determine the transmissivity distribution across a one-hectare test site. Two of the large-scale tests had constant but different rates of discharge; the remaining large-scale test had a discharge that was pulsed at regulated intervals. The small-scale tests were conducted at two well clusters 20 m apart. The program WELTEST was written to analyze the data. By using the methods of non-linear least squares regression analysis and Broyden's method to solve for non-linear extrema, WELTEST automatically determines the best values of transmissivity and the storage coefficient. The test results show that order of magnitude differences in the calculated transmissivities at a well location can be realized by varying the discharge rate at the pumping well, the duration of the aquifer test, and/or the location of the pumping well. The calculated storage coefficients for the tests cover a five-order magnitude range. The data show a definite trend for the storage coefficient to increase with the distance between the pumping and the observation wells. This trend is shown to be related to the orientation of high hydraulic conductivity zones between the pumping and the observation wells. A comparison among single-well aquifer tests, geological investigations and multi-well aquifer tests indicate that the multi-well tests are poorly suited for characterizing a transmissivity field. (Author) (11 refs., 14 figs.)

  19. ICDF Complex Remedial Action Work Plan

    Energy Technology Data Exchange (ETDEWEB)

    W. M. Heileson

    2006-12-01

    This Remedial Action Work Plan provides the framework for operation of the Idaho Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Disposal Facility Complex (ICDF). This facility includes (a) an engineered landfill that meets the substantial requirements of DOE Order 435.1, Resource Conservation and Recovery Act Subtitle C, Idaho Hazardous Waste Management Act, and Toxic Substances Control Act polychlorinated biphenyl landfill requirements; (b) centralized receiving, inspections, administration, storage/staging, and treatment facilities necessary for CERCLA investigation-derived, remedial, and removal waste at the Idaho National Laboratory (INL) prior to final disposition in the disposal facility or shipment off-Site; and (c) an evaporation pond that has been designated as a corrective action management unit. The ICDF Complex, including a buffer zone, will cover approximately 40 acres, with a landfill disposal capacity of approximately 510,000 yd3. The ICDF Complex is designed and authorized to accept INL CERCLA-generated wastes, and includes the necessary subsystems and support facilities to provide a complete waste management system. This Remedial Action Work Plan presents the operational approach and requirements for the various components that are part of the ICDF Complex. Summaries of the remedial action work elements are presented herein, with supporting information and documents provided as appendixes to this work plan that contain specific detail about the operation of the ICDF Complex. This document presents the planned operational process based upon an evaluation of the remedial action requirements set forth in the Operable Unit 3-13 Final Record of Decision.

  20. Remedial Action Programs annual meeting: Proceedings

    International Nuclear Information System (INIS)

    1988-01-01

    Within the DOE's Office of Nuclear Energy, the Office of Remedial Action and Waste Technology manages a number of programs whose purposes are to complete remedial actions at DOE facilities and sites located throughout the United States. These programs include the Surplus Facilities Management Program, the Formerly Utilized Sites Remedial Action Program, the Uranium Mill Tailings remedial Action Program and the West Valley Demonstration Project. The programs involve the decontamination and decommissioning of radioactively-contaminated structures and equipment, the disposal of uranium mill tailings, and the cleanup or restoration of soils and ground water that have been contaminated with radioactive hazardous substances. Each year the DOE and DOE-contractor staff who conduct these programs meet to exchange information and experience in common technical areas. This year's meeting was hosted by the Surplus Facilities Management Program and was held near DOE Headquarters, in Gaithersburg, Maryland. This volume of proceedings provides the record for the meeting. The proceedings consist of abstracts for each presentation made at the meeting, and the visual aids (if any) used by the speakers. The material is organized in the following pages according to the five different sessions at the meeting: Session 1: Environmental Compliance--Policy; Session 2: Environmental Compliance--Practice; Session 3: Reports from working groups; Session 4: DandD Technology; and Session 5: Remedial Action Technology. The agenda for the meeting and the list of meeting registrants are provided in Appendix A and B, respectively. Individual papers are processed separately for the data base

  1. Thermal remediation alters soil properties - a review.

    Science.gov (United States)

    O'Brien, Peter L; DeSutter, Thomas M; Casey, Francis X M; Khan, Eakalak; Wick, Abbey F

    2018-01-15

    Contaminated soils pose a risk to human and ecological health, and thermal remediation is an efficient and reliable way to reduce soil contaminant concentration in a range of situations. A primary benefit of thermal treatment is the speed at which remediation can occur, allowing the return of treated soils to a desired land use as quickly as possible. However, this treatment also alters many soil properties that affect the capacity of the soil to function. While extensive research addresses contaminant reduction, the range and magnitude of effects to soil properties have not been explored. Understanding the effects of thermal remediation on soil properties is vital to successful reclamation, as drastic effects may preclude certain post-treatment land uses. This review highlights thermal remediation studies that have quantified alterations to soil properties, and it supplements that information with laboratory heating studies to further elucidate the effects of thermal treatment of soil. Notably, both heating temperature and heating time affect i) soil organic matter; ii) soil texture and mineralogy; iii) soil pH; iv) plant available nutrients and heavy metals; v) soil biological communities; and iv) the ability of the soil to sustain vegetation. Broadly, increasing either temperature or time results in greater contaminant reduction efficiency, but it also causes more severe impacts to soil characteristics. Thus, project managers must balance the need for contaminant reduction with the deterioration of soil function for each specific remediation project. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. SUSTAINABLE REMEDIATION SOFTWARE TOOL EXERCISE AND EVALUATION

    Energy Technology Data Exchange (ETDEWEB)

    Kohn, J.; Nichols, R.; Looney, B.

    2011-05-12

    The goal of this study was to examine two different software tools designed to account for the environmental impacts of remediation projects. Three case studies from the Savannah River Site (SRS) near Aiken, SC were used to exercise SiteWise (SW) and Sustainable Remediation Tool (SRT) by including both traditional and novel remediation techniques, contaminants, and contaminated media. This study combined retrospective analysis of implemented projects with prospective analysis of options that were not implemented. Input data were derived from engineering plans, project reports, and planning documents with a few factors supplied from calculations based on Life Cycle Assessment (LCA). Conclusions drawn from software output were generally consistent within a tool; both tools identified the same remediation options as the 'best' for a given site. Magnitudes of impacts varied between the two tools, and it was not always possible to identify the source of the disagreement. The tools differed in their quantitative approaches: SRT based impacts on specific contaminants, media, and site geometry and modeled contaminant removal. SW based impacts on processes and equipment instead of chemical modeling. While SW was able to handle greater variety in remediation scenarios, it did not include a measure of the effectiveness of the scenario.

  3. Digital data sets that describe aquifer characteristics of the Tillman terrace and alluvial aquifer in southwestern Oklahoma

    Science.gov (United States)

    Becker, C.J.; Runkle, D.L.; Rea, Alan

    1997-01-01

    ARC/INFO export and nonproprietary format files This diskette contains digitized aquifer boundaries and maps of hydraulic conductivity, recharge, and ground-water level elevation contours for the Tillman terrace and alluvial aquifer in southwestern Oklahoma. The Tillman terrace aquifer encompasses the unconsolidated terrace deposits and alluvium associated with the North Fork of the Red River and the Red River in the western half of Tillman County. These sediments consist of discontinuous layers of clay, sandy clay, sand, and gravel. The aquifer extends over an area of 285 square miles and is used for irrigation and domestic purposes. Granite and the Hennessey Formation outcrop in northern parts of the aquifer where alluvial deposits are absent. These outcrops were included as part of the aquifer in a thesis that modeled the ground-water flow in the aquifer. Most of the aquifer boundaries and some of the lines in the hydraulic conductivity and recharge data sets were extracted from a published digital surficial geology data set based on a scale of 1:250,000. Most of the lines in the hydraulic conductivity, recharge, and 1969 water-level elevation contour data sets, and one line in the aquifer boundary data set were digitized from a paper map published at a scale of 1:249,695 in a thesis in which the ground-water flow in the aquifer was modeled. Ground-water flow models are numerical representations that simplify and aggregate natural systems. Models are not unique; different combinations of aquifer characteristics may produce similar results. Therefore, values of hydraulic conductivity and recharge used in the model and presented in this data set are not precise, but are within a reasonable range when compared to independently collected data.

  4. Decision Support System for Aquifer Recharge (AR) and Aquifer Storage and Recovery (ASR) Planning, Design, and Evaluation Decision Support System for Aquifer Recharge (AR) and Aquifer Storage and Recovery (ASR) Planning, Design, and Evaluation – Principles and Technical Basis

    Science.gov (United States)

    Aquifer recharge (AR) is a technical method being utilized to enhance groundwater resources through man-made replenishment means, such as infiltration basins and injections wells. Aquifer storage and recovery (ASR) furthers the AR techniques by withdrawal of stored groundwater at...

  5. Aquifer recharging in South Carolina: radiocarbon in environmental hydrogeology

    International Nuclear Information System (INIS)

    Stone, P.A.; Knox, R.L.; Mathews, T.D.

    1985-01-01

    Radiocarbon activities of dissolved inorganic carbon (and tritium activities where infiltration rates are rapid and aquifers shallow) provide relatively unambiguous and inexpensive evidence for identification of significant recharge areas. Such evidence is for the actual occurrence of modern recharge in the aquifer and thus is less inferential than stratigraphic or potentiometric evidence. These underutilized isotopic techniques are neither arcane nor complex and have been more-or-less standardized by earlier researchers. In South Carolina, isotopic evidence has been used from both calcareous and siliceous sedimentary aquifers and fractured crystalline rock aquifers. The Tertiary limestone aquifer is shown not to be principally recharged in its subcrop area, unlike conditions assumed for many other sedimentary aquifers in southeastern United States, and instead receives considerable lateral recharge from interfingering updip Tertiary sand aquifers in the middle coastal plain. Induced recharging at Hilton Head Island is mixing ancient relict water and modern recharge water. Recharging to deeper portions of the Cretaceous Middendorf basal sand aquifer occurs at least as far coastward as the middle coastal plain, near sampling sites that stratigraphically appear to be confined. Pronounced mineralization of water in fractured rocks cannot be considered as evidence of ancient or relict ground water that is isolated from modern contaminants, some of these waters contain considerable radiocarbon and hydrogen-bomb tritium

  6. Aquifers in coastal reclaimed lands - real world assessments

    Science.gov (United States)

    Saha, A.; Bironne, A.; Vonhögen-Peeters, L.; Lee, W. K.; Babovic, V. M.; Vermeulen, P.; van Baaren, E.; Karaoulis, M.; Blanchais, F.; Nguyen, M.; Pauw, P.; Doornenbal, P.

    2017-12-01

    Climate change and population growth are significant concerns in coastal regions around the world, where more than 30% of the world's population reside. The numbers continue to rise as coastal areas are increasingly urbanized. Urbanization creates land shortages along the coasts, which has spurred coastal reclamation activities as a viable solution. In this study, we focus on these reclamation areas; reclaimed areas in Singapore, and in the Netherlands, and investigate the potential of these reclaimed bodies as artificial aquifers that could attenuate water shortage problems in addition to their original purpose. We compare how the reclamation methods determine the hydrogeological characteristics of these manmade aquifers. We highlight similarities in freshwater lens development in the artificial shallow aquifers under natural recharge under diverse conditions, i.e. tropical and temperate zones, using numerical models. The characteristics and responses of these aquifers with dynamic freshwater-saltwater interface are contrasted against naturally occurring coastal aquifers where equilibrium was disturbed by anthropogenic activities. Finally, we assess the risks associated with subsidence and saltwater intrusion, combining measurements and numerical models, in case these aquifers are planned for Aquifer Storage and Recovery (ASR) or Managed Aquifer Recharge (MAR) strategies. Relative performances of some ASR schemes are simulated and compared in the reclaimed lands.

  7. Localized bedrock aquifer distribution explains discharge from a headwater catchment

    Science.gov (United States)

    Kosugi, Ken'ichirou; Fujimoto, Masamitsu; Katsura, Shin'ya; Kato, Hiroyuki; Sando, Yoshiki; Mizuyama, Takahisa

    2011-07-01

    Understanding a discharge hydrograph is one of the leading interests in catchment hydrology. Recent research has provided credible information on the importance of bedrock groundwater on discharge hydrographs from headwater catchments. However, intensive monitoring of bedrock groundwater is rare in mountains with steep topography. Hence, how bedrock groundwater controls discharge from a steep headwater catchment is in dispute. In this study, we conducted long-term hydrological observations using densely located bedrock wells in a headwater catchment underlain by granitic bedrock. The catchment has steep topography affected by diastrophic activities. Results showed a fairly regionalized distribution of bedrock aquifers within a scale of tens of meters, consisting of upper, middle, and lower aquifers, instead of a gradual and continuous decline in water level from ridge to valley bottom. This was presumably attributable to the unique bedrock structure; fault lines developed in the watershed worked to form divides between the bedrock aquifers. Spatial expanse of each aquifer and the interaction among aquifers were key factors to explain gentle and considerable variations in the base flow discharge and triple-peak discharge responses of the observed hydrograph. A simple model was developed to simulate the discharge hydrograph, which computed each of the contributions from the soil mantle groundwater, from the lower aquifer, and from the middle aquifer to the discharge. The modeling results generally succeeded in reproducing the observed hydrograph. Thus, this study demonstrated that understanding regionalized bedrock aquifer distribution is pivotal for explaining discharge hydrograph from headwater catchments that have been affected by diastrophic activities.

  8. Hydraulic properties from pumping tests data of aquifers in Azare ...

    African Journals Online (AJOL)

    Pumping test data from twelve boreholes in Azare area were analysed to determine the hydraulic properties of the aquifers, and the availability of water to meet the conjugate demands of the increasing population. The values of the aquifer constants obtained from the Cooper-Jacob's non-equilibrium graphical method were ...

  9. Modeling of groundwater flow for Mujib aquifer, Jordan

    Indian Academy of Sciences (India)

    Different scenarios were considered to predict aquifer system response under different conditions. The results of the sensitivity analysis show that ... decision makers and planners in selecting optimum management schemes suitable for arid .... Qatrana city where no water exists in the. B2/A7 aquifer. The proposed boundary ...

  10. Groundwater quality in the glacial aquifer system, United States

    Science.gov (United States)

    Stackelberg, Paul E.

    2017-12-07

    Groundwater provides nearly 50 percent of the Nation’s drinking water. To help protect this vital resource, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Project assesses groundwater quality in aquifers that are important sources of drinking water (Burow and Belitz, 2014). The glacial aquifer system constitutes one of the important areas being evaluated.

  11. Evaluation of Aquifer Characteristics of Voltaian Sedimentary Rocks ...

    African Journals Online (AJOL)

    Ground-water potential of the sedimentary aquifer system could be classified as high to intermediate to yield substantial groundwater resource for domestic and industrial water supply. To secure sub-stantial quantity of water for sustainable water supply in areas underlain by this sedimentary aqui-fer system in Ghana, ...

  12. Aquifers productivity in the Pan-African context

    Indian Academy of Sciences (India)

    The geoelectrical interpretation shows that almost all aquifers are made of the fractured portion of ... conductivity varies between 0.012 and 1.677 m/day, the resistivity between 3 and 825 Ωm, the thick- ... Aquifer depth; geoelectrical surveys; hydraulic conductivity; ordinary kriging; Pan-African context; pumping test. J. Earth ...

  13. Evaluation of the aquifer characteristic of Nanka Sands using ...

    African Journals Online (AJOL)

    In this study, we have coupled surface geophysical method with pumping test results to provide a cost effective and efficient alternative in aquifer parameter estimation. ... The interpretation of the VES data revealed 3 to 5 geoelectric units with the depth to aquifer varying from 7 to 108m and the resistivity of the saturated layer ...

  14. Hydrologic and isotopic study of the Quito aquifer

    International Nuclear Information System (INIS)

    Villalba, Fabio; Benalcazar, Julio; Garcia, Marco; Altamirano, Cesar; Altamirano, Homero; Sarasti, Santiago; Mancero, Maria; Leiva, Eduardo; Pino, Jose; Alulema, Rafael; Cedeno, Alberto; Burbano, Napoleon; Paquel, Efren; Becerra, Simon; Andrade, Graciela

    2000-10-01

    The dynamics of the Quito basin and surrounding area aquifers were determined through the use of stable and radioactive isotopes, and the monitoring of the freatic levels and of the bacteriological and physico-chemical quality of the water. A conceptual hydrodynamic model of the Quito aquifer was also proposed in order to establish in the future a sustainable management system

  15. Using Electrical Wireline Logs For Aquifer Characterization In Parts ...

    African Journals Online (AJOL)

    Interpretation by use of quantitative methods of electric log dataset was successfully applied to sandstone aquifers in parts of Anambra Basin of Nigeria. Depth to aquifers varies between 67 and 213m above mean sea level, porosity ranges between 13 and 55%. Transverse (unit) resistance T changes between 0.037 and ...

  16. Hydraulic Conductivity of a Firn Aquifer in Southeast Greenland

    Directory of Open Access Journals (Sweden)

    Olivia L. Miller

    2017-05-01

    Full Text Available Some regions of the Greenland ice sheet, where snow accumulation and melt rates are high, currently retain substantial volumes of liquid water within the firn pore space throughout the year. These firn aquifers, found between ~10 and 30 m below the snow surface, may significantly affect sea level rise by storing or draining surface meltwater. The hydraulic gradient and the hydraulic conductivity control flow of meltwater through the firn. Here we describe the hydraulic conductivity of the firn aquifer estimated from slug tests and aquifer tests at six sites located upstream of Helheim Glacier in southeastern Greenland. We conducted slug tests using a novel instrument, a piezometer with a heated tip that melts itself into the ice sheet. Hydraulic conductivity ranges between 2.5 × 10−5 and 1.1 × 10−3 m/s. The geometric mean of hydraulic conductivity of the aquifer is 2.7 × 10−4 m/s with a geometric standard deviation of 1.4 from both depth specific slug tests (analyzed using the Hvorslev method and aquifer tests during the recovery period. Hydraulic conductivity is relatively consistent between boreholes and only decreases slightly with depth. The hydraulic conductivity of the firn aquifer is crucial for determining flow rates and patterns within the aquifer, which inform hydrologic models of the aquifer, its relation to the broader glacial hydrologic system, and its effect on sea level rise.

  17. Hydraulic conductivity of a firn aquifer system in southeast Greenland

    Science.gov (United States)

    Miller, Olivia L.; Solomon, D. Kip; Miège, Clément; Koenig, Lora S.; Forster, Richard R.; Montgomery, Lynn N.; Schmerr, Nicholas; Ligtenberg, Stefan R. M.; Legchenko, Anatoly; Brucker, Ludovic

    2017-05-01

    Some regions of the Greenland ice sheet, where snow accumulation and melt rates are high, currently retain substantial volumes of liquid water within the firn pore space throughout the year. These firn aquifers, found between 10-30 m below the snow surface, may significantly affect sea level rise by storing or draining surface meltwater. The hydraulic gradient and the hydraulic conductivity control flow of meltwater through the firn. Here we describe the hydraulic conductivity of the firn aquifer estimated from slug tests and aquifer tests at six sites located upstream of Helheim Glacier in southeastern Greenland. We conducted slug tests using a novel instrument, a piezometer with a heated tip that melts itself into the ice sheet. Hydraulic conductivity ranges between 2.5x10-5 and 1.1x10-3 m/s. The geometric mean of hydraulic conductivity of the aquifer is 2.7x10-4 m/s with a geometric standard deviation of 1.4 from both depth specific slug tests (analyzed using the Hvorslev method) and aquifer tests during the recovery period. Hydraulic conductivity is relatively consistent between boreholes and only decreases slightly with depth. The hydraulic conductivity of the firn aquifer is crucial for determining flow rates and patterns within the aquifer, which inform hydrologic models of the aquifer, its relation to the broader glacial hydrologic system, and its effect on sea level rise.

  18. Hydrologic Properties of Aquifers in the Central Savannah River Area

    Energy Technology Data Exchange (ETDEWEB)

    Snipes, D.S.; Benson, S.M.; Price Jr., Van; Temples, T.J.

    1996-01-02

    The hydrologic properties of selected aquifer systems underlying the Milhaven and Girard sites in Georgia were determined through a series of aquifer performance tests performed from October, 1994 to January, 1995. At the Milhaven site, the systems under investigation consisted of the upper, middle and lower components of the Upper Floridan, the lower Dublin, and the lower Midville aquifers. At the Dublin site, only the lower Dublin and lower Midville aquifers were tested. In addition, the hydrologic properties of the lower Midville aquifer underlying the P, B and D Areas at the Savannah River Site were determined by a series of aquifer tests conducted in 1993 and 1994. The tests generally consisted of collecting water level and atmospheric data for 24 hours followed by a 72 hour pump test and a subsequent 72 hour recovery period. These tests were designed to determine the aquifer properties over a large area, to determine whether any hydrologic boundaries existed in the area, and to find out if leakance could be induced through the confining units which separated the aquifer units.

  19. Analytical solution of groundwater waves in unconfined aquifers with ...

    Indian Academy of Sciences (India)

    Selva Balaji Munusamy

    2017-07-29

    Jul 29, 2017 ... groundwater table becomes essential. Analytical solution of tide–aquifer interaction is important from field appli- cation [1] point of view. In the present work, the water table wave propagations in coastal aquifers are solved using a homotopy perturbation method with simple har- monic sinusoidal functions ...

  20. 40 CFR 149.3 - Critical Aquifer Protection Areas.

    Science.gov (United States)

    2010-07-01

    ... water supply from the sole or principal source aquifer, and (ii) Other economic costs and environmental... vulnerable to contamination due to the hydrogeologic characteristics of the unsaturated or saturated zone within the suggested critical aquifer protection area; and (2) Contamination of the sole or principal...

  1. Geophysical Study of Aquifer Properties at Isihor Village of Edo ...

    African Journals Online (AJOL)

    Ten (10) vertical electrical sounding (VES) (uniformly distributed) based on electrical resistivity method was carried out in a geophysical survey in order to study aquifer properties. These properties include depth, thickness and nature of soil above the aquifer. Schlumberger array of VES was conducted in Isihor Village and ...

  2. An updated water balance for the Grootfontein aquifer near Mahikeng

    African Journals Online (AJOL)

    Analysis of water levels and a water balance using recent assessments of groundwater abstractions confirm past work describing the hydrogeological functioning of the aquifer, and suggest that current abstractions need to fall by between 19 and 36 ML/day (7 and 13 Mm3/a) to bring the aquifer back into longterm balance.

  3. Determining hydraulic parameters of a karst aquifer using unique ...

    African Journals Online (AJOL)

    2014-07-15

    Jul 15, 2014 ... a first-ever attempt to utilise various sets of unique historical data derived from draining a large dolomitic karst aquifer by deep-level gold ... applying various types of analytical methods designed for porous media. In order to ... successfully applied to karst aquifers if the scale of investigation is large enough.

  4. Estimating aquifer transmissivity from geo-electrical sounding ...

    African Journals Online (AJOL)

    Abstract. A geophysical survey was carried out at Kaduna Polytechnic Senior Staff Quarters using Direct Current Electrical Resistivity method. The objectives were to determine different subsurface ... Qualitative interpretation indicates that the weathered/fractured. Basement constitutes the main aquifer unit. Aquifer resistivity ...

  5. Aquifer overexploitation: what does it mean?

    Science.gov (United States)

    Custodio, Emilio

    2002-02-01

    Groundwater overexploitation and aquifer overexploitation are terms that are becoming common in water-resources management. Hydrologists, managers and journalists use them when talking about stressed aquifers or some groundwater conflict. Overexploitation may be defined as the situation in which, for some years, average aquifer ion rate is greater than, or close to the average recharge rate. But rate and extent of recharge areas are often very uncertain. Besides, they may be modified by human activities and aquifer development. In practice, however, an aquifer is often considered as overexploited when some persistent negative results of aquifer development are felt or perceived, such as a continuous water-level drawdown, progressive water-quality deterioration, increase of ion cost, or ecological damage. But negative results do not necessarily imply that ion is greater than recharge. They may be simply due to well interferences and the long transient period that follow changes in the aquifer water balance. Groundwater storage is depleted to some extent during the transient period after ion is increased. Its duration depends on aquifer size, specific storage and permeability. Which level of "aquifer overexploitation" is advisable or bearable, depends on the detailed and updated consideration of aquifer-development effects and the measures implemented for correction. This should not be the result of applying general rules based on some indirect data. Monitoring, sound aquifer knowledge, and calculation or modelling of behaviour are needed in the framework of a set of objectives and policies. They should be established by a management institution, with the involvement of groundwater stakeholders, and take into account the environmental and social constraints. Aquifer overexploitation, which often is perceived to be associated with something ethically bad, is not necessarily detrimental if it is not permanent. It may be a step towards sustainable development. Actually

  6. Setting a benchmark in remediation

    International Nuclear Information System (INIS)

    Ong, Jacqueline

    2014-01-01

    Full text: Thiess Services has achieved a first in the treatment of contaminated soil, in the process assisting Orica in successfully removing a toxic legacy. In 1980, when Orica Australia's predecessor ICI Australia constructed its car park waste encapsulation (CPWE) to seal off contaminated soil at Botany Industrial Park, 12km south of the Sydney CBD, treatment methods were not available. Fast-forward more than 30 years and Thiess Services has successfully undertaken treatment of the soil, earning it the 2013 CARE award. The contaminated soil contained hexachlorobutadiene (HCBD), low levels of hexachlorobenzene and hexachloroethane, all by-products of historical manufacturing of chlorinated solvents, including dry cleaning fluid, in the 1960s and 1970s. ICI Australia decided initially to store the contaminated material in drums and place it on a bed of boiler ash. However, drum corrosion led to contamination of the ash bed and underlying soil, so the company decided to encapsulate the material within a synthetic Hypalon liner, covering it with clean soil and capping it with bitumen in a 45,000 cubic metre cell. In 2005, Orica commissioned Thiess to assess a range of remediation methods and technologies to treat the material. Three options were recommended — directly heated thermal desorption, in situ thermal desorption and indirectly heated thermal desorption. “Together with Orica, we decided that directly heated thermal desorption was the appropriate technology to use,” Thiess project manager Joshua Van Der Heiden said. “Essentially, the soil is introduced into a rotary kiln and a flame directly heats up the soil above the contaminants' boiling point (up to a maximum of 450C) so that the contaminants are volatilised and the soil comes out clean. The gas separated from the soil is then heated to around 1000C in a thermal oxidiser, converting it into carbon dioxide and water. To prevent contaminants from reforming, the gas stream is rapidly

  7. Review: The Yucatán Peninsula karst aquifer, Mexico

    DEFF Research Database (Denmark)

    Bauer-Gottwein, Peter; Gondwe, Bibi Ruth Neuman; Charvet, Guillaume

    2011-01-01

    The Yucatán Peninsula karst aquifer is one of the most extensive and spectacular karst aquifer systems on the planet. This transboundary aquifer system extends over an area of approximately 165,000 km2 in México, Guatemala and Belize. The Triassic to Holocene Yucatán limestone platform is located...... in the vicinity of the North American/Caribbean plate boundary and has been reshaped by a series of tectonic events over its long geologic history. At the end of the Cretaceous period, the Yucatán Peninsula was hit by a large asteroid, which formed the Chicxulub impact crater. The Yucatán Peninsula karst aquifer...... and population growth on the Peninsula. This review summarizes the state of knowledge on the Yucatán Peninsula karst aquifer and outlines the main challenges for hydrologic research and practical groundwater-resources management on the Peninsula....

  8. Hydrogeology of the Umm Er Radhuma Aquifer (Arabian peninsula)

    Science.gov (United States)

    Dirks, Heiko; Al Ajmi, Hussain; Kienast, Peter; Rausch, Randolf

    2018-03-01

    The aim of this article is to enhance the understanding of the Umm Er Radhuma aquifer's genesis, and its hydraulic and hydrochemical development over time. This is a prerequisite for wise use of the fossil groundwater resources contained within. The Umm Er Radhuma is a karstified limestone aquifer, extending over 1.6 Mio. km2 in the eastern part of the Arabian Peninsula. Both epigene and hypogene karstification contributed to the genesis of what is today the most prolific aquifer in the region. Besides man-made abstractions, even the natural outflows are higher than the small recharge (natural storage depletion). The Umm Er Radhuma shows that large aquifers in arid regions are never in "steady state" (where inflows equal outflows), considering Quaternary climate history. The aquifer's adaption to climate changes (precipitation, sea level) can be traced even after thousands of years, and is slower than the climate changes themselves.

  9. Technology development activities supporting tank waste remediation

    International Nuclear Information System (INIS)

    Bonner, W.F.; Beeman, G.H.

    1994-06-01

    This document summarizes work being conducted under the U.S. Department of Energy's Office of Technology Development (EM-50) in support of the Tank Waste Remediation System (TWRS) Program. The specific work activities are organized by the following categories: safety, characterization, retrieval, barriers, pretreatment, low-level waste, and high-level waste. In most cases, the activities presented here were identified as supporting tank remediation by EM-50 integrated program or integrated demonstration lead staff and the selections were further refined by contractor staff. Data sheets were prepared from DOE-HQ guidance to the field issued in September 1993. Activities were included if a significant portion of the work described provides technology potentially needed by TWRS; consequently, not all parts of each description necessarily support tank remediation

  10. Electrodialytic remediation of heavy metal polluted soil

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie

    2012-01-01

    Electrodialytic soil remediation is a method for removal of heavy metals. Good results have previously been obtained with both treatment of a stationary, water saturated soil matrix and with remediation of a stirred suspension of soil in water. The two different setups have different uses....... The first as in-situ or on-site treatment when there is no requirement for fast remediation, as the removal rate of the heavy metals are dependent on the distance between the electrodes (everything else equal) and in such application the electrode spacing must have a certain distance (often meters...... without a short distance between the membranes. The acidification of the suspended soil was fastest and following the mobilization of heavy metals. This may indicate that water splitting at the anion exchange membrane is used more efficiently in the stirred setup....

  11. Modeling of CO2 storage in aquifers

    International Nuclear Information System (INIS)

    Savioli, Gabriela B; Santos, Juan E

    2011-01-01

    Storage of CO 2 in geological formations is a means of mitigating the greenhouse effect. Saline aquifers are a good alternative as storage sites due to their large volume and their common occurrence in nature. The first commercial CO 2 injection project is that of the Sleipner field in the Utsira Sand aquifer (North Sea). Nevertheless, very little was known about the effectiveness of CO 2 sequestration over very long periods of time. In this way, numerical modeling of CO 2 injection and seismic monitoring is an important tool to understand the behavior of CO 2 after injection and to make long term predictions in order to prevent CO 2 leaks from the storage into the atmosphere. The description of CO 2 injection into subsurface formations requires an accurate fluid-flow model. To simulate the simultaneous flow of brine and CO 2 we apply the Black-Oil formulation for two phase flow in porous media, which uses the PVT data as a simplified thermodynamic model. Seismic monitoring is modeled using Biot's equations of motion describing wave propagation in fluid-saturated poroviscoelastic solids. Numerical examples of CO 2 injection and time-lapse seismics using data of the Utsira formation show the capability of this methodology to monitor the migration and dispersal of CO 2 after injection.

  12. IMPROVED NATURAL GAS STORAGE WELL REMEDIATION

    Energy Technology Data Exchange (ETDEWEB)

    James C. Furness; Donald O. Johnson; Michael L. Wilkey; Lynn Furness; Keith Vanderlee; P. David Paulsen

    2001-12-01

    This report summarizes the research conducted during Budget Period One on the project ''Improved Natural Gas Storage Well Remediation''. The project team consisted of Furness-Newburge, Inc., the technology developer; TechSavants, Inc., the technology validator; and Nicor Technologies, Inc., the technology user. The overall objectives for the project were: (1) To develop, fabricate and test prototype laboratory devices using sonication and underwater plasma to remove scale from natural gas storage well piping and perforations; (2) To modify the laboratory devices into units capable of being used downhole; (3) To test the capability of the downhole units to remove scale in an observation well at a natural gas storage field; (4) To modify (if necessary) and field harden the units and then test the units in two pressurized injection/withdrawal gas storage wells; and (5) To prepare the project's final report. This report covers activities addressing objectives 1-3. Prototype laboratory units were developed, fabricated, and tested. Laboratory testing of the sonication technology indicated that low-frequency sonication was more effective than high-frequency (ultrasonication) at removing scale and rust from pipe sections and tubing. Use of a finned horn instead of a smooth horn improves energy dispersal and increases the efficiency of removal. The chemical data confirmed that rust and scale were removed from the pipe. The sonication technology showed significant potential and technical maturity to warrant a field test. The underwater plasma technology showed a potential for more effective scale and rust removal than the sonication technology. Chemical data from these tests also confirmed the removal of rust and scale from pipe sections and tubing. Focusing of the underwater plasma's energy field through the design and fabrication of a parabolic shield will increase the technology's efficiency. Power delivered to the underwater plasma unit

  13. Ground-Water-Flow Modeling of a Freshwater and Brine-Filled Aquifer in the Onondaga Trough, Onondaga County, New York - A Summary of Findings

    Science.gov (United States)

    Kappel, William M.; Yager, Richard M.

    2008-01-01

    In 2007, the U.S. Geological Survey (USGS) completed a hydrogeologic study that included the development of a groundwater-flow model of the glacial-drift aquifer in the Onondaga Trough near Syracuse, N.Y., which extends from the Valley Heads Moraine near Tully, N.Y., to Onondaga Lake (fig. 1). Glacial sediments within the Onondaga Trough contain freshwater, saline water, and brine, which has historically supported several chemical industries in Syracuse. The ground-water-flow model was developed as a means to assist the members of the Onondaga Lake Partnership (local, State, and Federal governmental agencies) to assess remediation plans for Onondaga Lake and the Onondaga Creek watershed. Prior to this study, in the late 1990s, very little information was known about the physical nature of the valley-fill aquifer or the quality of water within it. Acquisition of this information would help local agencies understand the interactions of fresh and saline water within the aquifer and Onondaga Lake, and would facilitate the design of proposed and ongoing remediation work in and near the lake. The USGS study characterized the geology and geochemistry of the aquifer system, estimated the rate and direction of ground-water movement, and estimated mass loadings of chloride to Onondaga Lake and its tributaries from natural and anthropogenic sources. The study required analysis of existing hydrogeologic data and drilling of new test wells to collect additional hydrogeologic data to supplement this database. A three-dimensional geologic model of the unconsolidated deposits that fill the Onondaga Trough was developed from this information. Water-quality samples were collected, and hydraulic head (water-level) measurements were made in the test wells. The water samples were analyzed for a variety of chemical constituents to determine the composition and age of saline waters within the aquifer. The geologic model, together with the water-quality and hydraulic-head data, supported

  14. Superfund Record of Decision (EPA Region 5): Ossineke Groundwater Contamination Site, Alpena County, Ossineke, MI. (First remedial action), June 1991. Final report

    International Nuclear Information System (INIS)

    1991-01-01

    The Ossineke Ground Water Contamination site is an area overlying a contaminated aquifer in Ossineke, Alpena County, Michigan. The site hydrogeology is characterized by an upper aquifer and lower confined aquifer, both of which supply drinking water to local residents. Historically there have been two contaminant source areas of concern within Ossineke. Area 1 is in the center of the Town of Ossineke where two gas stations are located, consisting of underground storage tanks, and a former automobile rustproofing shop. Area 2 is a laundry and dry cleaning facility that has an associated wash water pond containing chlorinated hydrocarbons and VOCs. The State advised all users of the upper aquifer to stop using their wells. In 1982, the State discovered that a snow plow had hit a gasoline pump causing an unknown amount of gasoline to spill and, subsequently, contaminate the basements of several businesses. In 1986, the State replaced residential wells affected by ground water contamination. Because the contaminants of concern have been confirmed to be related to petroleum releases from underground storage tanks, the Superfund program does not have the authority to address cleanup under CERLCLA. The selected remedial action for the site is that no further action

  15. Mapping Contaminant Remediation with Electrical Resistivity Tomography

    Science.gov (United States)

    Gerhard, J.; Power, C.; Tsourlos, P.; Karaoulis, M.; Giannopoulos, A.; Soupios, P. M.; Simyrdanis, K.

    2014-12-01

    The remediation of sites contaminated with industrial chemicals - specifically dense non-aqueous phase liquids (DNAPLs) like coal tar and chlorinated solvents - represents a major geoenvironmental challenge. Remediation activities would benefit from a non-destructive technique to map the evolution of DNAPL mass in space and time. Electrical resistivity tomography (ERT) has long-standing potential in this context but has not yet become a common tool at DNAPL sites. This work evaluated the potential of time-lapse ERT for mapping DNAPL mass reduction in real time during remediation. Initially, a coupled DNAPL-ERT numerical model was developed for exploring this potential at the field scale, generating realistic DNAPL scenarios and predicting the response of an ERT survey. Also, new four-dimensional (4D) inversion algorithms were integrated for tracking DNAPL removal over time. 4D ERT applied at the surface for mapping an evolving DNAPL distribution was first demonstrated in a laboratory experiment. Independent simulation of the experiment demonstrated the reliability of the DNAPL-ERT model for simulating real systems. The model was then used to explore the 4D ERT approach at the field scale for a range of realistic DNAPL remediation scenarios. The approach showed excellent potential for mapping shallow DNAPL changes. However, remediation at depth was not as well resolved. To overcome this limitation, a new surface-to-horizontal borehole (S2HB) ERT configuration is proposed. A second laboratory experiment was conducted that demonstrated that S2HB ERT does better resolve changes in DNAPL distribution relative to surface ERT, particularly at depth. The DNAPL-ERT model was also used to demonstrate the improved mapping of S2HB ERT for field scale DNAPL scenarios. Overall, this work demonstrates that, with these innovations, ERT exhibits significant potential as a real time, non-destructive geoenvironmental remediation site monitoring tool.

  16. Electrodialytic remediation of suspended mine tailings

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Rojo, Adrian; Pino, Denisse

    2008-01-01

    This work shows the laboratory results of nine electrodialytic remediation experiments on copper mine tailings. A newly designed remediation cell, where the solids were kept in suspension by airflow, was tested. The results show that electric current could remove copper from suspended tailings...... experiment at 40 mA, with approximately 137.5 g mine tailings on dry basis. The removal for a static (baseline) experiment only amounted 15% when passing approximately the same amount of charge through 130 g of mine tailings. The use of air bubbling to keep the tailings suspended increased the removal...

  17. Remedial action planning for Trench 1

    International Nuclear Information System (INIS)

    Primrose, A.; Sproles, W.; Burmeister, M.; Wagner, R.; Law, J.; Greengard, T.; Castaneda, N.

    1998-01-01

    The accelerated action to remove the depleted uranium chips and associated soils and wastes from Trench 1 at the Rocky Flats Environmental Technology Site (RFETS) will begin in June 1998. To ensure that the remedial action is conducted safely, a rigorous and disciplined planning process was followed that incorporates the principles of Integrated Safety Management and Enhanced Work Planning. Critical to the success of the planning was early involvement of project staff (salaried and hourly) and associated technical support groups and disciplines. Feedback was and will continue to be solicited, and lessons learned incorporated to ensure the safe remediation of this site

  18. Piezometric levels as possible indicator of aquifer structure: analysis of the data from Maknassy basin aquifer system (Central Tunisia)

    International Nuclear Information System (INIS)

    Chenini, Ismail; Mammou, Abdallah Ben; Turki, Mohamed Moncef; Mercier, Eric

    2010-01-01

    The knowledge of piezometric data is of vast interest in many applications, such as assessing groundwater flow direction and identifying recharge zone of the aquifer. In this paper, a methodology is presented as a complementary approach to characterize multilayered aquifer system structure and functioning using piezometric data and the cartography of the hydraulic charge difference. The methodology is presented to gradually discriminate the aquifer system levels and to evaluate the spatial distribution of hydraulic heads. The hydraulic charge difference mapping permits to track spatial evolution of the impermeable levels. The methodology has been applied over the Maknassy basin aquifer system, located in central Tunisia. The obtained results, showing the multilayered aquifer structure, are validated using hydrochemical approach and piezometric data not considered in the reasoning. (author

  19. The use of in-situ dual vacuum extraction for remediation of soil and groundwater

    International Nuclear Information System (INIS)

    Trowbridge, B.E.; Ott, D.E.

    1992-01-01

    Dual Extraction provides a rapid and cost-effective method of remediating soil and groundwater impacted by volatile organic compounds (VOC's). Dual Extraction is the removal of both water and vapors through the same borehole using entrainment. This technology provides for the remediation of the vadose zone, capillary fringe, smear zone, and existing water table. The effectiveness of this technology is shown in a case study. A release from an Underground Storage Tank (UST) was responsible for a hydrocarbon plume spreading over approximately 50,000 square feet. The release produced vadose zone contamination in the silty and sandy clays from 10 - 30 feet below ground surface with TPH concentrations up to 1,400 mg/kg. A layer of free floating liquid hydrocarbon was present on a shallow aquifer located at 30 feet bgs in thicknesses ranging from 0.5 feet to 3.0 feet. An in-situ dual-extraction system was installed to remediate the soils and groundwater to levels as required by the Los Angeles Regional Water Quality Control Board (RWQCB). The system operated 24 hours/day for 196 days with an operating efficiency of over 99%. After 196 days, over 17,000 pounds of hydrocarbons had been extracted from the soils. Seven confirmatory soil borings were advanced in the area of highest initial hydrocarbon concentrations and indicated that TPH and BTEX concentrations had decreased over 99% from initial soil concentrations. Three confirmatory groundwater samples were obtained from monitoring wells initially exhibiting up to 3 feet of floating product. Confirmatory samples exhibited non-detectable (ND) concentrations of TPH and BTEX. Based upon the positive confirmatory results, site closure was obtained from the RWQCB in May of 1991. In only 28 weeks of operation, the groundwater contamination was reduced from free floating product to non-detectable concentrations of TPH using Dual Vacuum Extraction

  20. Position paper on the applicability of supplemental standards to the uppermost aquifer at the Uranium Mill Tailings Vitro Processing Site, Salt Lake City, Utah

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This report documents the results of the evaluation of the potential applicability of supplemental standards to the uppermost aquifer underlying the Uranium Mill Tailings Remedial Action (UMTRA) Project, Vitro Processing Site, Salt Lake City, Utah. There are two goals for this evaluation: provide the landowner with information to make an early qualitative decision on the possible use of the Vitro property, and evaluate the proposed application of supplemental standards as the ground water compliance strategy at the site. Justification of supplemental standards is based on the contention that the uppermost aquifer is of limited use due to wide-spread ambient contamination not related to the previous site processing activities. In support of the above, this report discusses the site conceptual model for the uppermost aquifer and related hydrogeological systems and establishes regional and local background water quality. This information is used to determine the extent of site-related and ambient contamination. A risk-based evaluation of the contaminants` effects on current and projected land uses is also provided. Reports of regional and local studies and U.S. Department of Energy (DOE) site investigations provided the basis for the conceptual model and established background ground water quality. In addition, a limited field effort (4 through 28 March 1996) was conducted to supplement existing data, particularly addressing the extent of contamination in the northwestern portion of the Vitro site and site background ground water quality. Results of the field investigation were particularly useful in refining the conceptual site model. This was important in light of the varied ground water quality within the uppermost aquifer. Finally, this report provides a critical evaluation, along with the related uncertainties, of the applicability of supplemental standards to the uppermost aquifer at the Salt Lake City Vitro processing site.

  1. Position paper on the applicability of supplemental standards to the uppermost aquifer at the Uranium Mill Tailings Vitro Processing Site, Salt Lake City, Utah

    International Nuclear Information System (INIS)

    1996-03-01

    This report documents the results of the evaluation of the potential applicability of supplemental standards to the uppermost aquifer underlying the Uranium Mill Tailings Remedial Action (UMTRA) Project, Vitro Processing Site, Salt Lake City, Utah. There are two goals for this evaluation: provide the landowner with information to make an early qualitative decision on the possible use of the Vitro property, and evaluate the proposed application of supplemental standards as the ground water compliance strategy at the site. Justification of supplemental standards is based on the contention that the uppermost aquifer is of limited use due to wide-spread ambient contamination not related to the previous site processing activities. In support of the above, this report discusses the site conceptual model for the uppermost aquifer and related hydrogeological systems and establishes regional and local background water quality. This information is used to determine the extent of site-related and ambient contamination. A risk-based evaluation of the contaminants' effects on current and projected land uses is also provided. Reports of regional and local studies and U.S. Department of Energy (DOE) site investigations provided the basis for the conceptual model and established background ground water quality. In addition, a limited field effort (4 through 28 March 1996) was conducted to supplement existing data, particularly addressing the extent of contamination in the northwestern portion of the Vitro site and site background ground water quality. Results of the field investigation were particularly useful in refining the conceptual site model. This was important in light of the varied ground water quality within the uppermost aquifer. Finally, this report provides a critical evaluation, along with the related uncertainties, of the applicability of supplemental standards to the uppermost aquifer at the Salt Lake City Vitro processing site

  2. A conceptual model of ground-water flow in the eastern Snake River Plain aquifer at the Idaho National Laboratory and vicinity with implications for contaminant transport

    Science.gov (United States)

    Ackerman, Daniel J.; Rattray, Gordon W.; Rousseau, Joseph P.; Davis, Linda C.; Orr, Brennon R.

    2006-01-01

    Ground-water flow in the west-central part of the eastern Snake River Plain aquifer is described in a conceptual model that will be used in numerical simulations to evaluate contaminant transport at the Idaho National Laboratory (INL) and vicinity. The model encompasses an area of 1,940 square miles (mi2) and includes most of the 890 mi2 of the INL. A 50-year history of waste disposal associated with research activities at the INL has resulted in measurable concentrations of waste contaminants in the aquifer. A thorough understanding of the fate and movement of these contaminants in the subsurface is needed by the U.S. Department of Energy to minimize the effect that contaminated ground water may have on the region and to plan effectively for remediation. Three hydrogeologic units were used to represent the complex stratigraphy of the aquifer in the model area. Collectively, these hydrogeologic units include at least 65 basalt-flow groups, 5 andesite-flow groups, and 61 sedimentary interbeds. Three rhyolite domes in the model area extend deep enough to penetrate the aquifer. The rhyolite domes are represented in the conceptual model as low permeability, vertical pluglike masses, and are not included as part of the three primary hydrogeologic units. Broad differences in lithology and large variations in hydraulic properties allowed the heterogeneous, anisotropic basalt-flow groups, andesite-flow groups, and sedimentary interbeds to be grouped into three hydrogeologic units that are conceptually homogeneous and anisotropic. Younger rocks, primarily thin, densely fractured basalt, compose hydrogeologic unit 1; younger rocks, primarily of massive, less densely fractured basalt, compose hydrogeologic unit 2; and intermediate-age rocks, primarily of slightly-to-moderately altered, fractured basalt, compose hydrogeologic unit 3. Differences in hydraulic properties among adjacent hydrogeologic units result in much of the large-scale heterogeneity and anisotropy of the

  3. Remediation Using Plants and Plant Enzymes: A Progress Report

    National Research Council Canada - National Science Library

    1995-01-01

    .... In every case, the sources are plants growing near the sediment. The use of plants for remediation of hazardous materials such as TNT or other munitions like RDX and HMX has led to a new approach to remediation-- phytoremediation...

  4. Printable Version of Mold Remediation in Schools and Commercial Buildings

    Science.gov (United States)

    This document presents guidelines for the remediation/cleanup of mold and moisture problems in schools and commercial buildings; these guidelines include measures designed to protect the health of building occupants and remediators.

  5. Functional remediation components: A conceptual method of evaluating the effects of remediation on risks to ecological receptors

    Energy Technology Data Exchange (ETDEWEB)

    Burger, Joanna; Gochfeld, Michael; Bunn, Amoret; Downs, Janelle; Jeitner, Christian; Pittfield, Taryn; Salisbury, Jennifer

    2016-08-30

    Governmental agencies, regulators, health professionals, tribal leaders, and the public are faced with understanding and evaluating the effects of cleanup activities on species, populations, and ecosystems. While engineers and managers understand the processes involved in different remediation types such as capping, pump and treat, and natural attenuation, there is often a disconnect between (1) how ecologists view the influence of different types of remediation, (2) how the public perceives them, and (3) how engineers understand them. The overall goal of the present investigation was to define the components of remediation types (= functional remediation). Objectives were to (1) define and describe functional components of remediation, regardless of the remediation type, (2) provide examples of each functional remediation component, and (3) explore potential effects of functional remediation components in the post-cleanup phase that may involve continued monitoring and assessment. Functional remediation components include types, numbers, and intensity of people, trucks, heavy equipment, pipes, and drill holes, among others. Several components may be involved in each remediation type, and each results in ecological effects, ranging from trampling of plants, to spreading invasive species, to disturbing rare species, and to creating fragmented habitats. In some cases remediation may exert a greater effect on ecological receptors than leaving the limited contamination in place. A goal of this conceptualization is to break down functional components of remediation such that managers, regulators, and the public might assess the effects of timing, extent, and duration of different remediation options on ecological systems.

  6. Initial study of thermal energy storage in unconfined aquifers. [UCATES

    Energy Technology Data Exchange (ETDEWEB)

    Haitjema, H.M.; Strack, O.D.L.

    1986-04-01

    Convective heat transport in unconfined aquifers is modeled in a semi-analytic way. The transient groundwater flow is modeled by superposition of analytic functions, whereby changes in the aquifer storage are represented by a network of triangles, each with a linearly varying sink distribution. This analytic formulation incorporates the nonlinearity of the differential equation for unconfined flow and eliminates numerical dispersion in modeling heat convection. The thermal losses through the aquifer base and vadose zone are modeled rather crudely. Only vertical heat conduction is considered in these boundaries, whereby a linearly varying temperature is assumed at all times. The latter assumption appears reasonable for thin aquifer boundaries. However, assuming such thin aquifer boundaries may lead to an overestimation of the thermal losses when the aquifer base is regarded as infinitely thick in reality. The approach is implemented in the computer program UCATES, which serves as a first step toward the development of a comprehensive screening tool for ATES systems in unconfined aquifers. In its present form, the program is capable of predicting the relative effects of regional flow on the efficiency of ATES systems. However, only after a more realistic heatloss mechanism is incorporated in UCATES will reliable predictions of absolute ATES efficiencies be possible.

  7. Relation entre nappes superficielles et aquifère profond dans le bassin de Sfax (Tunisie)Relationship between shallow and deep aquifers in the Sfax basin (Tunisia).

    Science.gov (United States)

    Ahmed Maliki, My; Krimissa, Mohamed; Michelot, Jean-Luc; Zouari, Kamel

    2000-07-01

    The study of the isotopic composition ( 18O and 2H) of groundwater collected in the Sfax basin (Tunisia), helped to understand the behaviour of the different aquifers. It showed that the groundwater in the deep aquifer is old, probably slow moving and recharged under a colder climate than at present. The increasing exploitation of the shallow aquifers probably favoured upward leakage from the deep aquifer. Isotope balance equations allowed us to estimate the contribution of the deep aquifer to the shallow aquifer recharge.

  8. Electrokinetic remediation of copper mine tailings

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Rojo, Adrián; Ottosen, Lisbeth M.

    2007-01-01

    in sulphuric acidified tailings) without bipolar electrodes to 42% when bipolar electrodes were implemented. Furthermore, the results showed that in this system sulphuric acid addition prior to remediation was better than citric acid addition. In addition, applying a too strong electric field (even...

  9. Proceedings: Conference on Compensatory/Remedial Education.

    Science.gov (United States)

    Fea, Henry R., Ed.; And Others

    This document presents the papers and discussions from the Conference on Compensatory/Remedial Education. The contents include: "Institutional Programs for the Low Achievers" by Joan G. Roloff; "Communication in Compensatory Education" by Henry R. Fea; "Seminar: Special Programs for Minorities" by Constance Acholonu; "Seminar: Special Programs for…

  10. Hanford Site Tank Waste Remediation System

    International Nuclear Information System (INIS)

    1993-05-01

    The US Department of Energy's (DOE) Hanford Site in southeastern Washington State has the most diverse and largest amount of highly radioactive waste of any site in the US. High-level radioactive waste has been stored in large underground tanks since 1944. A Tank Waste Remediation System Program has been established within the DOE to safely manage and immobilize these wastes in anticipation of permanent disposal in a geologic repository. The Hanford Site Tank Waste Remediation System Waste Management 1993 Symposium Papers and Viewgraphs covered the following topics: Hanford Site Tank Waste Remediation System Overview; Tank Waste Retrieval Issues and Options for their Resolution; Tank Waste Pretreatment - Issues, Alternatives and Strategies for Resolution; Low-Level Waste Disposal - Grout Issue and Alternative Waste Form Technology; A Strategy for Resolving High-Priority Hanford Site Radioactive Waste Storage Tank Safety Issues; Tank Waste Chemistry - A New Understanding of Waste Aging; Recent Results from Characterization of Ferrocyanide Wastes at the Hanford Site; Resolving the Safety Issue for Radioactive Waste Tanks with High Organic Content; Technology to Support Hanford Site Tank Waste Remediation System Objectives

  11. Some aspects of remediation of contaminated soils

    Science.gov (United States)

    Bech, Jaume; Korobova, Elena; Abreu, Manuela; Bini, Claudio; Chon, Hyo-Taek; Pérez-Sirvent, Carmen; Roca, Núria

    2014-05-01

    Soils are essential components of the environment, a limited precious and fragile resource, the quality of which should be preserved. The concentration, chemical form and distribution of potential harmful elements in soils depends on parent rocks, weathering, soil type and soil use. However, their concentration can be altered by mismanagement of industrial and mining activities, energy generation, traffic increase, overuse of agrochemicals, sewage sludge and waste disposal, causing contamination, environmental problems and health concerns. Heavy metals, some metalloids and radionuclides are persistent in the environment. This persistence hampers the cost/efficiency of remediation technologies. The choice of the most appropriate soil remediation techniques depends of many factors and essentially of the specific site. This contribution aims to offer an overview of the main remediation methods in contaminated soils. There are two main groups of technologies: the first group dealing with containment and confinement, minimizing their toxicity, mobility and bioavailability. Containment measures include covering, sealing, encapsulation and immobilization and stabilization. The second group, remediation with decontamination, is based on the remotion, clean up and/or destruction of contaminants. This group includes mechanical procedures, physical separations, chemical technologies such as soil washing with leaching or precipitation of harmful elements, soil flushing, thermal treatments and electrokinetic technologies. There are also two approaches of biological nature: bioremediation and phytoremediation. Case studies from Chile, Ecuador, Italy, Korea, Peru, Portugal, Russia and Spain, will be discussed in accordance with the time available.

  12. Remedial Education--Is It Worth It?

    Science.gov (United States)

    Cosby, Jon P.

    A cost analysis of the developmental education program on the North Campus of Florida Junior College at Jacksonville revealed that in the 1972/1973 fiscal year the special credit courses offered for remedial students cost over 80 percent more than regular credit courses. Among the developmental courses offered (English, reading, mathematics, and…

  13. Gradient remediability in linear distributed parabolic systems ...

    African Journals Online (AJOL)

    The aim of this paper is the introduction of a new concept that concerned the analysis of a large class of distributed parabolic systems. It is the general concept of gradient remediability. More precisely, we study with respect to the gradient observation, the existence of an input operator (gradient efficient actuators) ensuring ...

  14. TRADITIONAL REMEDIES IN CHILDREN AROUND EASTERN ...

    African Journals Online (AJOL)

    hi-tech

    2003-08-08

    Aug 8, 2003 ... remain largely unproven by the scientific method and the concern about adverse effects have led to closer scrutiny of these products (4). Whereas most traditional remedies are safe, the potential for adverse effects or intoxication exists, as does the possibility of interaction with conventional drugs (2, 5-8).

  15. Remedial Action Program annual conference: Proceedings

    International Nuclear Information System (INIS)

    1990-01-01

    Within the DOE's Office of Environmental Restoration ampersand Waste Management, the Office of Environmental Restoration manages a number of programs whose purposes are to complete remedial actions at DOE facilities and sites located throughout the United States. The programs include the Surplus Facilities Management Program, the Formerly Utilized Sites Remedial Action Program, the Uranium Mill Tailings Remedial Action Program, and the West Valley Demonstration Project. These programs involve the decontamination and decommissioning of radioactively-contaminated structures and equipment, the disposal of uranium mill tailings, and the cleanup or restoration of soils and ground water that have been contaminated with radioactive or hazardous substances. Each year the DOE and DOE-contractor staff who conduct these programs meet to exchange information and experience in common technical areas. This year's meeting was hosted by the Uranium Mill Tailings Remedial Action Project, DOE-AL, and was held in Albuquerque, NM. This volume of proceedings is the record of that conference. The proceedings consist of abstracts, summaries, or actual text for each presentation made and any visual aids used by the speakers

  16. Tank waste remediation system program plan

    International Nuclear Information System (INIS)

    Powell, R.W.

    1998-01-01

    This program plan establishes the framework for conduct of the Tank Waste Remediation System (TWRS) Project. The plan focuses on the TWRS Retrieval and Disposal Mission and is specifically intended to support the DOE mid-1998 Readiness to Proceed with Privatized Waste Treatment evaluation for establishing firm contracts for waste immobilization

  17. Tank waste remediation system mission analysis report

    International Nuclear Information System (INIS)

    Acree, C.D.

    1998-01-01

    The Tank Waste Remediation System Mission Analysis Report identifies the initial states of the system and the desired final states of the system. The Mission Analysis Report identifies target measures of success appropriate to program-level accomplishments. It also identifies program-level requirements and major system boundaries and interfaces

  18. Bioventing feasibility test to aid remediation strategy

    CSIR Research Space (South Africa)

    Pearce, K

    1998-01-01

    Full Text Available A case study is presented where the feasibility of bioventing was assessed for the remediation of a petroleum-contaminated site. This was achieved through the determination of the radius of influence of a single vent well, the soil gas permeability...

  19. Land Conversion, Social Impacts, and Legal Remedies ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Land Conversion, Social Impacts, and Legal Remedies: Understanding the Role of Community Paralegals in Addressing Impacts of Land Use Change in Asia. This project addresses the ... sur la prospérité commune. Le CRDI se joint au Forum économique mondial afin de présenter les pratiques de croissance inclusives.

  20. Enhanced Electrokinetic Remediation of Cadmium Contaminated Soil

    African Journals Online (AJOL)

    In an attempt to remediate contaminated soil, a new technique of purging cadmium from soil is examined by enhanced electrokinetic method. It involves the passage of low level direct current between two electrodes in the soil to remove contaminant. An apparatus consisting of four principal parts; soil cell, electrode ...

  1. Teachers' Knowledge, Identification and Remediation of Writing ...

    African Journals Online (AJOL)

    ... reduce teacher-pupil ratios and conduct periodic health checks on pupils in order to identify and isolate medical problems were suggested as some of the ways of tackling writing and other learning problems in the primary school. Key words: Botswana, identification, primary schools, remediation, teachers' knowledge, ...

  2. An ancient greek pain remedy for athletes

    DEFF Research Database (Denmark)

    Bartels, Else M.; Swaddling, Judith; Harrison, Adrian Paul

    2006-01-01

    While Hippocratic writings make no reference to the actual Olympics, there is frequent mention of diet, exercise, and the treatment of injuries sustained by the athletic participants. Indeed, Galen in his Composition of Medicines gives details of a remedy prescribed for the relief of pains and sw...

  3. Decision process for Hanford sitewide groundwater remediation

    International Nuclear Information System (INIS)

    Chiaramonte, G.R.

    1996-06-01

    This document describes a decision process for planning future investigations and remediating contaminated groundwater at the Hanford Site in Richland, Washington. This decision process details the following: identifies key decisions and activities; defines the criteria used in making each decision; and defines the logic that links the decisions and the activities in a stepwise manner

  4. Tank waste remediation system program plan

    Energy Technology Data Exchange (ETDEWEB)

    Powell, R.W.

    1998-01-05

    This program plan establishes the framework for conduct of the Tank Waste Remediation System (TWRS) Project. The plan focuses on the TWRS Retrieval and Disposal Mission and is specifically intended to support the DOE mid-1998 Readiness to Proceed with Privatized Waste Treatment evaluation for establishing firm contracts for waste immobilization.

  5. On the importance of default breach remedies

    NARCIS (Netherlands)

    Sloof, R.; Oosterbeek, H.; Sonnemans, J.

    2007-01-01

    Theory predicts that default breach remedies are immaterial whenever contracting costs are negligible. Some experimental studies, however, suggest that in practice default rules do matter, as they may affect parties' preferences over contract terms. This paper presents results from an experiment

  6. Modelling remediation options for urban contamination situations

    DEFF Research Database (Denmark)

    Thiessen, K.M.; Andersson, Kasper Grann; Charnock, T.W.

    2009-01-01

    and remedial options enables the evaluation of a variety of situations or alternative recovery strategies in contexts of preparedness or decision-making. At present a number of models and modelling approaches are available for different purposes. This paper summarizes the available modelling approaches...

  7. 42 CFR 50.606 - Remedies.

    Science.gov (United States)

    2010-10-01

    ... may decide that a particular conflict of interest will bias the objectivity of the PHS-funded research... Remedies. (a) If the failure of an Investigator to comply with the conflict of interest policy of the... actions regarding conflicting financial interests in PHS-funded research, including a requirement for...

  8. 45 CFR 94.6 - Remedies.

    Science.gov (United States)

    2010-10-01

    ... Remedies. (a) If the failure of an Investigator to comply with the conflict of interest policy of the... actions regarding conflicting financial interests in PHS-funded research, including a review of all..., the PHS Awarding Component may decide that a particular conflict of interest will bias the objectivity...

  9. Remediation of soil contaminated with polycyclic aromatic ...

    African Journals Online (AJOL)

    The aim of this study was to determine ways of remediating soils contaminated with polycyclic aromatic hydrocarbons (PAHs) associated with crude oil. The study involves the use of planted cowpeas, mushrooms, algae, dead vegetable and live earthworm, and fire-heating of the contaminated garden soil collected from the ...

  10. 40 CFR 85.1803 - Remedial Plan.

    Science.gov (United States)

    2010-07-01

    ... repairs performed by outlets other than the vehicle manufacturer's franchised dealers. No maintenance or... perform the repair under the remedial plan to affix a label to each vehicle or engine repaired or, when... and vehicles or engines incorporating a proposed change, repair, or modification reasonably designed...

  11. Preliminary Investigations Of Effectiveness Of Herbal Remedies ...

    African Journals Online (AJOL)

    This study analysed some of the widely publicised herbal remedies in use for HIV infection in Nigeria, and investigated their efficacy scientifically. Those found to be efficacious will be subjected to further analysis to identify their active chemical components. The research deals directly with patients living with HIV/AIDS that ...

  12. Remediation of feedlot effluents using aquatic plants

    OpenAIRE

    Rizzo, Pedro Federico; Arreghini, Silvana; Serafini, Roberto José María; Bres, Patricia Alina; Crespo, Diana Elvira; Fabrizio de Iorio, Alicia Rosa

    2012-01-01

    Feedlots have increased in several regions of Argentina, particularly in the Pampas. The absence of adequate treatments of the effluents produced in these establishments creates serious problems to the society. Phytoremediation can be defined as inexpensive and environmentally sustainable strategy used to remove pollutants by plants. The aim of this study was to evaluate the remediation potential of two ...

  13. Microbial Remediation of Metals in Soils

    Science.gov (United States)

    Hietala, K. A.; Roane, T. M.

    Of metal-contaminated systems, metal-contaminated soils present the greatest challenge to remediation efforts because of the structural, physical, chemical, and biological heterogeneities encountered in soils. One of the confounding issues surrounding metal remediation is that metals can be readily re-mobilized, requiring constant monitoring of metal toxicity in sites where metals are not removed. Excessive metal content in soils can impact air, surface water, and groundwater quality. However, our understanding of how metals affect organisms, from bacteria to plants and animals, and our ability to negate the toxicity of metals are in their infancies. The ubiquity of metal contamination in developing and industrialized areas of the world make remediation of soils via removal, containment, and/or detoxification of metals a primary concern. Recent examples of the health and environmental consequences of metal contamination include arsenic in drinking water (Wang and Wai 2004), mercury levels in fish (Jewett and Duffy 2007), and metal uptake by agricultural crops (Howe et al. 2005). The goal of this chapter is to summarize the traditional approaches and recent developments using microorganisms and microbial products to address metal toxicity and remediation.

  14. The Call for Colloquialisms: Origins and Remedies

    Science.gov (United States)

    Salah, Reem

    2015-01-01

    This research aims at discovering the gap between Standard Arabic and the current spoken varieties of Arabic due to social, educational, political, colonial, and media factors. The researcher will try to also analyse the causes of the current gap and suggest remedies. Standard Arabic (SA) or FuSha (the Arabic term for "standard Arabic")…

  15. Screening of fungi for soil remediation potential

    Science.gov (United States)

    Richard T. Lamar; Laura M. Main; Diane M. Dietrich; John A. Glaser

    1999-01-01

    The purpose of the present investigation was to determine if physiological and/or biochemical factors such as growth rate, tolerance to and ability to degrade PCP or creosote have use for predicting the potential bioremediation performance of fungi. Because we have focused the initial development of a fungal-based soil remediation technology on PCP- and/or creosote-...

  16. TRADITIONAL REMEDIES IN CHILDREN AROUND EASTERN ...

    African Journals Online (AJOL)

    hi-tech

    2003-08-08

    Aug 8, 2003 ... Objective: To gauge the views of mothers and other caregivers on the use of traditional remedies in the community. Design: Descriptive study. Setting: Five health centres affliated to the UNITRA, Faculty of Health Sciences. Methods: Medical students administered a questionnaire to mothers and other ...

  17. An ancient Greek pain remedy for athletes

    DEFF Research Database (Denmark)

    Bartels, Else M; Swaddling, Judith; Harrison, Adrian P

    2006-01-01

    While Hippocratic writings make no reference to the actual Olympics, there is frequent mention of diet, exercise, and the treatment of injuries sustained by the athletic participants. Indeed, Galen in his Composition of Medicines gives details of a remedy prescribed for the relief of pains...

  18. Land Conversion, Social Impacts, and Legal Remedies ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Land Conversion, Social Impacts, and Legal Remedies: Understanding the Role of Community Paralegals in Addressing Impacts of Land Use Change in Asia. This project ... There is a recognized need for intermediary institutions, such as media, political parties, and unions that help citizens exercise their rights. Community ...

  19. Electrodialytic Remediation of Different Cu-Polluted Soils

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Hansen, Henrik K.; Hansen, Lene

    1999-01-01

    Based on characterization of a polluted soil a proper desorbing agent to be added to the soil before the remediation can be found. The desorbing agent can improve the remediation according to both energy consumption and duration of the action......Based on characterization of a polluted soil a proper desorbing agent to be added to the soil before the remediation can be found. The desorbing agent can improve the remediation according to both energy consumption and duration of the action...

  20. 78 FR 19261 - Safe Drinking Water Act Sole Source Aquifer Program; Designation of Bainbridge Island, Washington...

    Science.gov (United States)

    2013-03-29

    ... principle source of drinking water for the citizens of Bainbridge Island and that this aquifer system, if... designation. II. Basis for Determination EPA defines a sole or principle source aquifer as an aquifer or... ENVIRONMENTAL PROTECTION AGENCY Safe Drinking Water Act Sole Source Aquifer Program; Designation...

  1. Petroleum hydrocarbon contaminated sites: a review of investigation and remediation regulations and processes

    Energy Technology Data Exchange (ETDEWEB)

    Epelbaum, Michel; Claudio, Jair R. [Bureau Veritas do Brasil Sociedade Classificadora e Certificadora Ltda., Sao Paulo, SP (Brazil)

    1993-12-31

    This paper discusses alternatives on remediation of petroleum hydrocarbon contaminated sites which include groundwater remediation techniques and soil remediation techniques. Finally, the work points out some trends of sites remediation in Brazil and abroad. 6 refs., 1 fig., 7 tabs.

  2. Groundwater level responses to precipitation variability in Mediterranean insular aquifers

    Science.gov (United States)

    Lorenzo-Lacruz, Jorge; Garcia, Celso; Morán-Tejeda, Enrique

    2017-09-01

    Groundwater is one of the largest and most important sources of fresh water on many regions under Mediterranean climate conditions, which are exposed to large precipitation variability that includes frequent meteorological drought episodes, and present high evapotranspiration rates and water demand during the dry season. The dependence on groundwater increases in those areas with predominant permeable lithologies, contributing to aquifer recharge and the abundance of ephemeral streams. The increasing pressure of tourism on water resources in many Mediterranean coastal areas, and uncertainty related to future precipitation and water availability, make it urgent to understand the spatio-temporal response of groundwater bodies to precipitation variability, if sustainable use of the resource is to be achieved. We present an assessment of the response of aquifers to precipitation variability based on correlations between the Standardized Precipitation Index (SPI) at various time scales and the Standardized Groundwater Index (SGI) across a Mediterranean island. We detected three main responses of aquifers to accumulated precipitation anomalies: (i) at short time scales of the SPI (24 months). The differing responses were mainly explained by differences in lithology and the percentage of highly permeable rock strata in the aquifer recharge areas. We also identified differences in the months and seasons when aquifer storages are more dependent on precipitation; these were related to climate seasonality and the degree of aquifer exploitation or underground water extraction. The recharge of some aquifers, especially in mountainous areas, is related to precipitation variability within a limited spatial extent, whereas for aquifers located in the plains, precipitation variability influence much larger areas; the topography and geological structure of the island explain these differences. Results indicate large spatial variability in the response of aquifers to precipitation in

  3. TECHNICAL GUIDANCE DOCUMENT: CONSTRUCTION QUALITY MANAGEMENT FOR REMEDIAL ACTION AND REMEDIAL DESIGN WASTE CONTAINMENT SYSTEMS

    Science.gov (United States)

    This Technical Guidance Document is intended to augment the numerous construction quality control and construction quality assurance (CQC and CQA) documents that are available far materials associated with waste containment systems developed for Superfund site remediation. In ge...

  4. IAEA Remediation Mission Issues Final Report

    International Nuclear Information System (INIS)

    2011-01-01

    Full text: A team of international experts today completed their assessment of the strategy and plans being considered by the Japanese authorities to remediate the areas off-site TEPCO's Fukushima Daiichi Nuclear Power Plant (NPP). Their Final Report, delivered to the Japanese authorities, is available here. ''A lot of good work, done at all levels, is on-going in Japan in the area of environmental remediation,'' said Juan Carlos Lentijo, Team Leader and General Director for Radiation Protection at Spain's nuclear regulatory authority. In the report, Japan is encouraged to continue its remediation efforts, taking into account the advice provided by the Mission. ''In the early phases of the Fukushima Daiichi accident, a very cautious approach was adopted by the Japanese authorities in terms of dealing with the handling of residue materials. It is considered right to do so,'' Lentijo said. ''However, at this point in time, we see that there is room to take a more balanced approach, focussing on the real priority areas, classifying residue materials and adopting appropriate remediation measures on the basis of the results of safety assessments for each specific situation.'' The IAEA stands ready to support Japan as it continues its efforts to remediate the environment in the area off-site the Fukushima Daiichi NPP. The IAEA sent the mission to Japan from 7 to 15 October 2011 following a request from the country's government. The mission, comprising 12 international and IAEA experts from several countries, visited numerous locations in the Fukushima Prefecture and conducted meetings in Tokyo and Fukushima with Japanese officials from several ministries and institutions. A Preliminary Summary Report was issued on 14 October. Background The accident at the Fukushima Daiichi NPP has led to elevated levels of radiation over large areas. The Government of Japan has been formulating a strategy and plans to implement countermeasures to remediate these areas. The IAEA

  5. Fate of arsenic, phosphate and ammonium plumes in a coastal aquifer affected by saltwater intrusion.

    Science.gov (United States)

    Colombani, N; Mastrocicco, M; Prommer, H; Sbarbati, C; Petitta, M

    2015-08-01

    A severe groundwater contamination with extensive plumes of arsenic, phosphate and ammonium was found in a coastal aquifer beneath a former fertilizer production plant. The implementation of an active groundwater remediation strategy, based on a comprehensive pump and treat scheme, now prevents the migration of the dissolved contaminants into the marine environment. However, due to the site's proximity to the coastline, a seawater wedge was induced by the pumping scheme. Additionally the groundwater flow and salinity patterns were also strongly affected by leakage from the site's sewer system and from a seawater-fed cooling canal. The objective of this study was to elucidate the fate of arsenic and its co-contaminants over the site's history under the complex, coupled hydrodynamic and geochemical conditions that prevail at the site. A detailed geochemical characterisation of samples from sediment cores and hydrochemical data provided valuable high-resolution information. The obtained data were used to develop various conceptual models and to constrain the development and calibration of a reactive transport model. The reactive transport simulations were performed for a sub-domain (two-dimensional transect) of an earlier developed three-dimensional flow and variable density solute transport model. The results suggest that in the upper sub-oxic zone the influx of oxygenated water promoted As attenuation via co-precipitation with Al and Fe oxides and copper hydroxides. In contrast, in the deeper aquifer zone, iron reduction, associated with the release of adsorbed As and the dissolution of As bearing phases, provided and still provides to date a persistent source for groundwater pollution. The presented monitoring and modelling approach could be broadly applied to coastal polluted sites by complex contaminant mixture containing As. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Hydrologic time and sustainability of shallow aquifers

    Science.gov (United States)

    Back, William; ,

    1994-01-01

    Measurement of water and short intervals of time are coeval events that began about 6000 BC in Mesopotamia. Even though time and hydrology have been intimately entwined, with time terms in the denominator of many hydrologic parameters, hydrology's a priori claim to time has not been consummated. Moreover, time takes on a greater importance now than in the past as the focus shifts to small site-scale aquifers whose sustainability can be physically and chemically threatened. One of the challenges for research in hydrogeology is to establish time scales for hydrologic phenomena such as infiltration rates, groundwater flow rates, rates of organic and inorganic reactions, and rates of groundwater withdrawal over the short term, and the long term and to understand the consequences of these various time scales. Credible monitoring programs must consider not only the spatial scale, but also the time scale of the phenomena being monitored.

  7. Nitrate reduction in an unconfined sandy aquifer

    DEFF Research Database (Denmark)

    Postma, Diederik Jan; Boesen, Carsten; Kristiansen, Henning

    1991-01-01

    of total dissolved ions in the NO3- free anoxic zone indicates the downward migration of contaminants and that active nitrate reduction is taking place. Nitrate is apparently reduced to N2 because both nitrite and ammonia are absent or found at very low concentrations. Possible electron donors......Nitrate distribution and reduction processes were investigated in an unconfined sandy aquifer of Quaternary age. Groundwater chemistry was studied in a series of eight multilevel samplers along a flow line, deriving water from both arable and forested land. Results show that plumes of nitrate...... processes of O2 and NO3- occur at rates that are fast compared to the rate of downward water transport. Nitrate-contaminated groundwater contains total contents of dissolved ions that are two to four times higher than in groundwater derived from the forested area. The persistence of the high content...

  8. Convective Flow in an Aquifer Layer

    Directory of Open Access Journals (Sweden)

    Dambaru Bhatta

    2017-10-01

    Full Text Available Here, we investigate weakly nonlinear hydrothermal two-dimensional convective flow in a horizontal aquifer layer with horizontal isothermal and rigid boundaries. We treat such a layer as a porous medium, where Darcy’s law holds, subjected to the conditions that the porous layer’s permeability and the thermal conductivity are variable in the vertical direction. This analysis is restricted to the case that the subsequent hydraulic resistivity and diffusivity have a small rate of change with respect to the vertical variable. Applying the weakly nonlinear approach, we derive various order systems and express their solutions. The solutions for convective flow quantities such as vertical velocity and the temperature that arise as the Rayleigh number exceeds its critical value are computed and presented in graphical form.

  9. Gender, Age and Locus of Control as Correlates of Remedial ...

    African Journals Online (AJOL)

    The study sought to explain remedial learners' attitude towards English language using three variables: gender, age and locus of control. Three properly validated instruments were used to collect data on the relevant variables from 385 remedial English learners randomly selected from 5 remedial education centers in ...

  10. Development of remedial method for teaching electric circuits in ...

    African Journals Online (AJOL)

    Also it attempted to develop a remedial teaching method that would be used to remedy any identified misconceptions. An electric circuit Remedial Teaching Method was therefore developed, and its impact was assessed using a nonrandomized control pretest/post-test design. The percentages of students who had various ...

  11. 45 CFR 91.50 - Exhaustion of administrative remedies.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Exhaustion of administrative remedies. 91.50... Investigation, Conciliation, and Enforcement Procedures § 91.50 Exhaustion of administrative remedies. (a) A complainant may file a civil action following the exhaustion of administrative remedies under the Act...

  12. 12 CFR 1780.56 - Exhaustion of administrative remedies.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Exhaustion of administrative remedies. 1780.56 Section 1780.56 Banks and Banking OFFICE OF FEDERAL HOUSING ENTERPRISE OVERSIGHT, DEPARTMENT OF HOUSING... Posthearing Proceedings § 1780.56 Exhaustion of administrative remedies. To exhaust administrative remedies as...

  13. 14 CFR 1252.410 - Exhaustion of administrative remedies.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Exhaustion of administrative remedies. 1252..., Conciliation, and Enforcement Procedures § 1252.410 Exhaustion of administrative remedies. (a) A complainant may file a civil action following the exhaustion of administrative remedies under the Act...

  14. 12 CFR 908.66 - Exhaustion of administrative remedies.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Exhaustion of administrative remedies. 908.66 Section 908.66 Banks and Banking FEDERAL HOUSING FINANCE BOARD FEDERAL HOUSING FINANCE BOARD ORGANIZATION... Proceedings § 908.66 Exhaustion of administrative remedies. To exhaust administrative remedies as to any issue...

  15. 45 CFR 1156.21 - Exhaustion of administrative remedies.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Exhaustion of administrative remedies. 1156.21... Investigation, Conciliation, and Enforcement Procedures § 1156.21 Exhaustion of administrative remedies. (a) A complainant may file a civil action following the exhaustion of administrative remedies under the Act...

  16. 43 CFR 17.339 - Exhaustion of administrative remedies.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Exhaustion of administrative remedies. 17... Investigation, Conciliation, and Enforcement Procedures § 17.339 Exhaustion of administrative remedies. (a) A complainant may file a civil action following the exhaustion of administrative remedies under the Act...

  17. 7 CFR 400.453 - Exhaustion of administrative remedies.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Exhaustion of administrative remedies. 400.453 Section 400.453 Agriculture Regulations of the Department of Agriculture (Continued) FEDERAL CROP INSURANCE...-Compliance § 400.453 Exhaustion of administrative remedies. All administrative remedies contained herein or...

  18. 10 CFR 1040.89-13 - Exhaustion of administrative remedies.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Exhaustion of administrative remedies. 1040.89-13 Section... Investigation, Conciliation and Enforcement Procedures § 1040.89-13 Exhaustion of administrative remedies. (a) A complainant may file a civil action following the exhaustion of administrative remedies under the Act...

  19. Predicting the phytoextraction duration to remediate heavy metal contaminated soils

    NARCIS (Netherlands)

    Koopmans, G.F.; Römkens, P.F.A.M.; Song, J.; Temminghoff, E.J.M.; Japenga, J.

    2007-01-01

    The applicability of phytoextraction to remediate soils contaminated with heavy metals (HMs) depends on, amongst others, the duration before remediation is completed. The impact of changes in the HM content in soil occurring during remediation on plant uptake has to be considered in order to obtain

  20. Calculating the Costs of Remedial Placement Testing. CCRC Analytics

    Science.gov (United States)

    Rodríguez, Olga; Bowden, Brooks; Belfield, Clive; Scott-Clayton, Judith

    2015-01-01

    Of the more than one million new students who enter community colleges each fall, nearly 70 percent are assigned to remedial coursework. The cost of providing this coursework is high, yet evidence about the effectiveness of remediation is not compelling. In addition, many students are misclassified in the remedial assessment process. In order for…

  1. Remediation trials of crude oil contaminated soil using different ...

    African Journals Online (AJOL)

    A 3 month remediation trial of the use of detergent and sawdust in different combination forms in the restoration of a crude oil contaminated tropical soil was investigated. 8 remediation treatments labeled A – H in addition to the control (I) were used in 10 kg soil artificially polluted with 300 ml crude oil each. Remediation ...

  2. Contaminant transport in the Snake River Plain Aquifer: Phase 1, Part 1: Simple analytical model of individual plumes

    International Nuclear Information System (INIS)

    Rood, A.S.; Arnett, R.C.; Barraclough, J.T.

    1989-05-01

    A preliminary, semi-quantitative assessment of the migration of INEL effluents in the Snake River Plain Aquifer (SRPA) was performed. This study focused on past tritium, 129 I, and 90 Sr effluents from the Idaho Chemical Processing Plant (ICPP) and Test Reactor Area (TRA) and carbon tetrachloride from the Radioactive Waste Management Complex (RWMC). The disposal ponds at TRA and the ICPP injection well were the primary means of liquid radioactive waste discharge from the ICPP and TRA. Drums containing solidified chlorinated solvents disposed of at the RWMC were the primary source of carbon tetrachloride. Water samples taken from wells located in the SRPA show detectable quantities of the four contaminants. The predicted radionuclide concentrations exceed drinking water limits in limited areas within the INEL boundaries. Without planned remedial action, carbon tetrachloride is predicted to exceed drinking water limits beyond the site boundaries near the middle of the next century. 16 refs., 23 figs., 3 tabs

  3. [Cognitive remediation and work outcome in schizophrenia].

    Science.gov (United States)

    Franck, N

    2014-06-01

    Recovery is partly defined by the patients' capacity to work, since doing well in a job favors hope and responsibilities' taking. Diminished job placement or tenure is linked with cognitive disorders, which impact directly and indirectly (through negative symptoms) functional outcomes. Attention, executive functions and working memory disorders can result in an alteration of the ability to manage the tasks required in the workplace. Executive function, working memory and social cognition disorders may also have an impact on behavior in relationships. Cognitive disorders do not automatically directly contribute to vocational outcome, yet their effects may be mediated by other variables such as symptoms, metacognition, social skills and intrinsic motivation. Then, since all these dimensions have to be taken into account, reducing the impact of cognitive troubles becomes a major challenge for the care of schizophrenia. Cognitive remediation is the more effective therapeutic tool to reduce cognitive dysfunctions. It rests in particular on the development of new strategies that allow taking concrete situations into account more efficiently. Cognitive remediation reduces the detrimental consequences of cognitive disorders and permits their compensation. It has emerged as an effective treatment, that improves not only cognitive abilities but also functioning, as it has been shown by numerous randomized controlled studies and several meta-analyses. The present article considers the effects on cognitive remediation on work function in schizophrenia. Several randomized controlled trials that compared supported employment alone versus supported employment associated with cognitive remediation showed significant improvement of employment rates in the latter condition. These results favor the use of cognitive remediation before job placement. The specific needs of the occupation that will be provided and the cognitive profile of the user should be taken into account. Copyright

  4. Optimal Aquifer Pumping Policy to Reduce Contaminant Concentration

    Directory of Open Access Journals (Sweden)

    Ali Abaei

    2012-01-01

    Full Text Available Different sources of ground water contamination lead to non-uniform distribution of contaminant concentration in the aquifer. If elimination or containment of pollution sources was not possible, the distribution of contaminant concentrations could be modified in order to eliminate peak concentrations using optimal water pumping discharge plan. In the present investigation Visual MODFLOW model was used to simulate the flow and transport in a hypothetic aquifer. Genetic Algorithm (GA also was applied to optimize the location and pumping flow rate of wells in order to reduce contaminants peak concentrations in aquifer.

  5. Identifying Stream/Aquifer Exchange by Temperature Gradient in a Guarani Aquifer System Outcrop Zone

    Science.gov (United States)

    Wendland, E.; Rosa, D. M. S.; Anache, J. A. A.; Lowry, C.; Lin, Y. F. F.

    2017-12-01

    Recharge of the Guarani Aquifer System (GAS) in South America is supposed to occur mainly in the outcrop zones, where the GAS appears as an unconfined aquifer (10% of the 1.2 Million km2 aquifer extension). Previous evaluations of recharge are based essentially on water balance estimates for the whole aquifer area or water table fluctuations in monitoring wells. To gain a more detailed understanding of the recharge mechanisms the present work aimed to study the stream aquifer interaction in a watershed (Ribeirão da Onça) at an outcrop zone. Two Parshall flumes were installed 1.3 km apart for discharge measurement in the stream. Along this distance an optic fiber cable was deployed to identify stretches with gaining and losing behavior. In order to estimate groundwater discharge in specific locations, 8 temperature sticks were set up along the stream reach to measure continuously the vertical temperature gradient. A temperature probe with 4 thermistors was also used to map the shallow streambed temperature gradient manually along the whole distance. The obtained results show a discharge difference of 250 m3/h between both flumes. Since the last significant rainfall (15 mm) in the watershed occurred 3 months ago, this value can be interpreted as the base flow contribution to the stream during the dry season. Given the temperature difference between groundwater ( 24oC) and surface water ( 17oC) the fiber-optic distributed temperature sensing (FO-DTS) allowed the identification of stretches with gaining behavior. Temperature gradients observed at the streambed varied between 0.67 and 14.33 oC/m. The study demonstrated that heat may be used as natural tracer even in tropical conditions, where the groundwater temperature is higher than the surface water temperature during the winter. The obtained results show that the discharge difference between both flumes can not be extrapolated without detailed analysis. Gaining and loosing stretches have to be identified on order

  6. Hydrogeology and water quality of the Floridan aquifer system and effect of Lower Floridan aquifer withdrawals on the Upper Floridan aquifer at Barbour Pointe Community, Chatham County, Georgia, 2013

    Science.gov (United States)

    Gonthier, Gerard; Clarke, John S.

    2016-06-02

    Two test wells were completed at the Barbour Pointe community in western Chatham County, near Savannah, Georgia, in 2013 to investigate the potential of using the Lower Floridan aquifer as a source of municipal water supply. One well was completed in the Lower Floridan aquifer at a depth of 1,080 feet (ft) below land surface; the other well was completed in the Upper Floridan aquifer at a depth of 440 ft below land surface. At the Barbour Pointe test site, the U.S. Geological Survey completed electromagnetic (EM) flowmeter surveys, collected and analyzed water samples from discrete depths, and completed a 72-hour aquifer test of the Floridan aquifer system withdrawing from the Lower Floridan aquifer.Based on drill cuttings, geophysical logs, and borehole EM flowmeter surveys collected at the Barbour Pointe test site, the Upper Floridan aquifer extends 369 to 567 ft below land surface, the middle semiconfining unit, separating the two aquifers, extends 567 to 714 ft below land surface, and the Lower Floridan aquifer extends 714 to 1,056 ft below land surface.A borehole EM flowmeter survey indicates that the Upper Floridan and Lower Floridan aquifers each contain four water-bearing zones. The EM flowmeter logs of the test hole open to the entire Floridan aquifer system indicated that the Upper Floridan aquifer contributed 91 percent of the total flow rate of 1,000 gallons per minute; the Lower Floridan aquifer contributed about 8 percent. Based on the transmissivity of the middle semiconfining unit and the Floridan aquifer system, the middle semiconfining unit probably contributed on the order of 1 percent of the total flow.Hydraulic properties of the Upper Floridan and Lower Floridan aquifers were estimated based on results of the EM flowmeter survey and a 72-hour aquifer test completed in Lower Floridan aquifer well 36Q398. The EM flowmeter data were analyzed using an AnalyzeHOLE-generated model to simulate upward borehole flow and determine the transmissivity of

  7. Remedial Design/Remedial Action Work Plan for Operable Units 6-05 and 10-04, Phase III

    Energy Technology Data Exchange (ETDEWEB)

    R. P. Wells

    2006-09-19

    The remedial design/remedial action for Operable Unit 6-05 (Waste Area Group 6) and Operable Unit 10-04 (Waste Area Group 10) - collectively called Operable Unit 10-04 has been divided into four phases. Phase I consists of developing and implementing institutional controls at Operable Unit 10-04 sites and developing and implementing Idaho National Laboratory-wide plans for both institutional controls and ecological monitoring. Phase II will remediate sites contaminated with trinitrotoluene and Royal Demolition Explosive. Phase III will remediate lead contamination at a gun range, and Phase IV will remediate hazards from unexploded ordnance. This Phase III remedial Design/Remedial Action Work Plan addresses the remediation of lead-contaminated soils found at the Security Training Facility (STF)-02 Gun Range located at the Idaho National Laboratory. Remediation of the STF-02 Gun Range will include excavating contaminated soils; physically separating copper and lead for recycling; returning separated soils below the remediation goal to the site; stabilizing contaminated soils, as required, and disposing of the separated soils that exceed the remediation goal; encapsulating and disposing of creosote-contaminated railroad ties and power poles; removing and disposing of the wooden building and asphalt pads found at the STF-02 Gun Range; sampling and analyzing soil to determine the excavation requirements; and when the remediation goals have been met, backfilling and contouring excavated areas and revegetating the affected area.

  8. Water quality of the Edwards Aquifer and streams recharging the aquifer in the San Antonio region, Texas

    Science.gov (United States)

    Roddy, W.R.

    1992-01-01

    The Edwards aquifer in south-central Texas is one of the most productive and most important aquifers in the State, with an average annual discharge of about 608,000 acre-ft of water during 1932-82 (Reeves and Ozuna, 1985).  The Edwards aquifer is the principal source of water for municipal, industrial, and irrigation use in all or parts of five counties- Bexar, Comal, hays, Medina, and Uvalde- and is the only source of water for San Antonio, the tenth-largest city in the United States (1980 population, 786,000) (A.H. Belo Corporation, 1985).

  9. Estimating harvested rainwater at greenhouses in south Portugal aquifer Campina de Faro for potential infiltration in Managed Aquifer Recharge.

    Science.gov (United States)

    Costa, Luís; Monteiro, José Paulo; Leitão, Teresa; Lobo-Ferreira, João Paulo; Oliveira, Manuel; Martins de Carvalho, José; Martins de Carvalho, Tiago; Agostinho, Rui

    2015-04-01

    The Campina de Faro (CF) aquifer system, located on the south coast of Portugal, is an important source of groundwater, mostly used for agriculture purposes. In some areas, this multi-layered aquifer is contaminated with high concentration of nitrates, possibly arising from excessive usage of fertilizers, reaching to values as high as 300 mg/L. In order to tackle this problem, Managed Aquifer Recharge (MAR) techniques are being applied at demonstration scale to improve groundwater quality through aquifer recharge, in both infiltration basins at the river bed of ephemeral river Rio Seco and existing traditional large diameter wells located in this aquifer. In order to assess the infiltration capacity of the existing infrastructures, in particular infiltration basins and large diameter wells at CF aquifer, infiltration tests were performed, indicating a high infiltration capacity of the existing infrastructures. Concerning the sources of water for recharge, harvested rainwater at greenhouses was identified in CF aquifer area as one of the main potential sources for aquifer recharge, once there is a large surface area occupied by these infrastructures at the demo site. This potential source of water could, in some cases, be redirected to the large diameter wells or to the infiltration basins at the riverbed of Rio Seco. Estimates of rainwater harvested at greenhouses were calculated based on a 32 year average rainfall model and on the location of the greenhouses and their surface areas, the latter based on aerial photograph. Potential estimated annual rainwater intercepted by greenhouses at CF aquifer accounts an average of 1.63 hm3/year. Nonetheless it is unlikely that the totality of this amount can be harvested, collected and redirected to aquifer recharge infrastructures, for several reasons, such as the lack of appropriate greenhouse infrastructures, conduits or a close location between greenhouses and large diameter wells and infiltration basins. Anyway, this

  10. The in-situ decontamination of sand and gravel aquifers by chemically enhanced solubilization of multiple-compound DNAPLs with surfactant solutions: Phase 1 -- Laboratory and pilot field-scale testing and Phase 2 -- Solubilization test and partitioning and interwell tracer tests. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-24

    Laboratory, numerical simulation, and field studies have been conducted to assess the potential use of micellar-surfactant solutions to solubilize chlorinated solvents contaminating sand and gravel aquifers. Ninety-nine surfactants were screened for their ability to solubilize trichloroethene (TCE), perchloroethylene (PCE), and carbon tetrachloride (CTET). The field test was conducted in the alluvial aquifer which is located 20 to 30 meters beneath a vapor degreasing operation at Paducah Gaseous Diffusion Plant. This aquifer has become contaminated with TCE due to leakage of perhaps 40,000 liters of TCE, which has generated a plume of dissolved TCE extending throughout an area of approximately 3 km{sup 2} in the aquifer. Most of the TCE is believed to be present in the overlying lacustrine deposits and in the aquifer itself as a dense, non-aqueous phase liquid, or DNAPL. The objective of the field test was to assess the efficacy of the surfactant for in situ TCE solubilization. Although the test demonstrated that sorbitan monooleate was unsuitable as a solubilizer in this aquifer, the single-well test was demonstrated to be a viable method for the in situ testing of surfactants or cosolvents prior to proceeding to full-scale remediation.

  11. The in-situ decontamination of sand and gravel aquifers by chemically enhanced solubilization of multiple-compound DNAPLs with surfactant solutions. Phase 1: Laboratory and pilot field-scale testing. Phase 2: Solubilization test and partitioning interwell tracer tests. Final report

    International Nuclear Information System (INIS)

    1997-01-01

    Laboratory, numerical simulation, and field studies have been conducted to assess the potential use of micellar-surfactant solutions to solubilize chlorinated solvents contaminating sand and gravel aquifers. Ninety-nine surfactants were screened for their ability to solubilize trichloroethene (TCE), perchloroethylene (PCE), and carbon tetrachloride (CTET). The field test was conducted in the alluvial aquifer which is located 20 to 30 meters beneath a vapor degreasing operation at Paducah Gaseous Diffusion Plant. This aquifer has become contaminated with TCE due to leakage of perhaps 40,000 liters of TCE, which has generated a plume of dissolved TCE extending throughout an area of approximately 3 km 2 in the aquifer. Most of the TCE is believed to be present in the overlying lacustrine deposits and in the aquifer itself as a dense, non-aqueous phase liquid, or DNAPL. The objective of the field test was to assess the efficacy of the surfactant for in situ TCE solubilization. Although the test demonstrated that sorbitan monooleate was unsuitable as a solubilizer in this aquifer, the single-well test was demonstrated to be a viable method for the in situ testing of surfactants or cosolvents prior to proceeding to full-scale remediation

  12. Hydrogeology - AQUIFER_SYSTEMS_UNCONSOLIDATED_IDNR_IN: Unconsolidated Aquifer Systems of Indiana (Indiana Department of Natural Resources, 1:48,000, Polygon Shapefile)

    Data.gov (United States)

    NSGIC State | GIS Inventory — AQUIFER_SYSTEMS_UNCONSOLIDATED_IDNR_IN is a polygon shapefile that shows unconsolidated aquifer systems of the state of Indiana at a scale of 1:48,000. The following...

  13. Hydrogeological modelling of the Atlantis aquifer for management ...

    African Journals Online (AJOL)

    Hydrogeological modelling of the Atlantis aquifer for management support to the Atlantis Water Supply Scheme. Nebo Jovanovic, Richard DH Bugan, Gideon Tredoux, Sumaya Israel, Rodney Bishop, Vernon Marinus ...

  14. Hydraulic conductivities of fractures and matrix in Slovenian carbonate aquifers

    Directory of Open Access Journals (Sweden)

    Timotej Verbovšek

    2008-12-01

    Full Text Available Hydraulic conductivities and specific storage coefficients of fractures and matrix in Slovenian carbonate aquifers were determined by Barker’s method for pumping test analysis, based on fractional flow dimension. Values are presented for limestones and mainly for dolomites, and additionally for separate aquifers, divided by age andlithology in several groups. Data was obtained from hydrogeological reports for 397 water wells, and among these, 79 pumping tests were reinterpreted. Hydraulic conductivities of fractures are higher than the hydraulic conductivities of matrix, and the differences are highly statistically significant. Likewise, differences are significant for specific storage, and the values of these coefficients are higher in the matrix. Values of all coefficients vary in separate aquifers, and the differences can be explained by diagenetic effects, crystal size, degree of fracturing, andcarbonate purity. Comparison of the methods, used in the reports, and the Barker’s method (being more suitable for karstic and fractured aquifers, shows that the latter fits real data better.

  15. Functional Microbial Diversity Explains Groundwater Chemistry in a Pristine Aquifer

    Science.gov (United States)

    Microbial communities inhabiting anoxic aquifers catalyze critical biogeochemical reactions in the subsurface, yet little is known about how their community structure correlates with groundwater chemistry. In this study, we described the composition of microbial communities in th...

  16. Aquifers productivity in the Pan-African context

    Indian Academy of Sciences (India)

    , including 14 near existing boreholes for comparison. Aquifer parameters of hydraulic conductivity and transmissivity were obtained by analyzing pumping test data from existing boreholes. An empirical relationship between hydraulic ...

  17. Sole Source Aquifers, Region 9, 2008, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — There are 7 polygons representing 6 individual sole source aquifer boundaries and one streamflow source area in California, Arizona, and Nevada. Various efforts were...

  18. Quantification of River Nile/Quaternary aquifer exchanges via ...

    Indian Academy of Sciences (India)

    www.ias.ac.in/article/fulltext/jess/125/08/1697-1711 ... Abstract. This study approach seeks to characterize the hydraulic interactions between the Nile and the Quaternary aquifer via riverbank filtration (RBF) in Abu Tieg area, Assuit Governorate.

  19. Groundwater availability of the Denver Basin aquifer system, Colorado

    Science.gov (United States)

    Paschke, Suzanne

    2011-01-01

    The Denver Basin aquifer system is a critical water resource for growing municipal, industrial, and domestic uses along the semiarid Front Range urban corridor of Colorado. The confined bedrock aquifer system is located along the eastern edge of the Rocky Mountain Front Range where the mountains meet the Great Plains physiographic province. Continued population growth and the resulting need for additional water supplies in the Denver Basin and throughout the western United States emphasize the need to continually monitor and reassess the availability of groundwater resources. In 2004, the U.S. Geological Survey initiated large-scale regional studies to provide updated groundwater-availability assessments of important principal aquifers across the United States, including the Denver Basin. This study of the Denver Basin aquifer system evaluates the hydrologic effects of continued pumping and documents an updated groundwater flow model useful for appraisal of hydrologic conditions.

  20. Intrinsic and enhanced biodegradation of benzene in strongly reduced aquifers

    NARCIS (Netherlands)

    Heiningen, W.N.M. van; Rijnaarts, H.H.M; Langenhoff, A.A.M.

    1999-01-01

    Laboratory microcosm studies were performed to examine intrinsic and enhanced benzene bioremediation using five different sediment and groundwater samples from three deeply anaerobic aquifers sited in northern Netherlands. The influence of addition of nitrate, sulfate, limited amounts of oxygen, and

  1. Modelling the effects of tides and storm surges on coastal aquifers using a coupled surface-subsurface approach.

    Science.gov (United States)

    Yang, Jie; Graf, Thomas; Herold, Maria; Ptak, Thomas

    2013-06-01

    Coastal aquifers are complex hydrologic systems because many physical processes interact: (i) variably saturated flow, (ii) spatial-temporal fluid density variations, (iii) tidal fluctuations, (iv) storm surges overtopping dykes, and (v) surface runoff of storm water. The HydroGeoSphere model is used to numerically simulate coastal flow dynamics, assuming a fully coupled surface-subsurface approach, accounting for all processes listed above. The diffusive wave approximation of the St. Venant equation is used to describe surface flow. Surface flow and salt transport are fully coupled with subsurficial variably saturated, variable-density flow and salt transport through mathematical terms that represent exchange of fluid mass and solute mass, respectively. Tides and storm surges induce a time-variant head that is applied to nodes of the surface domain. The approach is applied to real cases of tide and storm surge events. Tide simulation results confirm the existence of a recirculating zone, forming beneath the upper part of the intertidal zone. By monitoring the exchange fluid flux rates through the beach, it was found that the major inflow to the aquifer takes place at the upper part of the intertidal zone, which explains the formation of the recirculating zone. The recirculating zone is forming particularly during rising tide. Results from a storm surge simulation show that plume fingers develop below the flooded land surface. Natural remediation by seaward flowing freshwater is relatively slow, such that reducing the salt concentration in the aquifer down to drinking water standards takes up to 10 years. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Enrichment of Geobacter species in response to stimulation of Fe(III) reduction in sandy aquifer sediments

    Science.gov (United States)

    Snoeyenbos-West, O.L.; Nevin, K.P.; Anderson, R.T.; Lovely, D.R.

    2000-01-01

    Engineered stimulation of Fe(III) has been proposed as a strategy to enhance the immobilization of radioactive and toxic metals in metal-contaminated subsurface environments. Therefore, laboratory and field studies were conducted to determine which microbial populations would respond to stimulation of Fe(III) reduction in the sediments of sandy aquifers. In laboratory studies, the addition of either various organic electron donors or electron shuttle compounds stimulated Fe(III) reduction and resulted in Geobacter sequences becoming important constituents of the Bacterial 16S rDNA sequences that could be detected with PCR amplification and denaturing gradient gel electrophoresis (DGGE). Quantification of Geobacteraceae sequences with a PCR most-probable-number technique indicated that the extent to which numbers of Geobacter increased was related to the degree of stimulation of Fe(III) reduction. Geothrix species were also enriched in some instances, but were orders of magnitude less numerous than Geobacter species. Shewanella species were not detected, even when organic compounds known to be electron donors for Shewanella species were used to stimulate Fe(III) reduction in the sediments. Geobacter species were also enriched in two field experiments in which Fe(III) reduction was stimulated with the addition of benzoate or aromatic hydrocarbons. The apparent growth of Geobacter species concurrent with increased Fe(III) reduction suggests that Geobacter species were responsible for much of the Fe(III) reduction in all of the stimulation approaches evaluated in three geographically distinct aquifers. Therefore, strategies for subsurface remediation that involve enhancing the activity of indigenous Fe(III)-reducing populations in aquifers should consider the physiological properties of Geobacter species in their treatment design.

  3. Cost estimating for CERCLA remedial alternatives a unit cost methodology

    International Nuclear Information System (INIS)

    Brettin, R.W.; Carr, D.J.; Janke, R.J.

    1995-06-01

    The United States Environmental Protection Agency (EPA) Guidance for Conducting Remedial Investigations and Feasibility Studies Under CERCLA, Interim Final, dated October 1988 (EPA 1988) requires a detailed analysis be conducted of the most promising remedial alternatives against several evaluation criteria, including cost. To complete the detailed analysis, order-of-magnitude cost estimates (having an accuracy of +50 percent to -30 percent) must be developed for each remedial alternative. This paper presents a methodology for developing cost estimates of remedial alternatives comprised of various technology and process options with a wide range of estimated contaminated media quantities. In addition, the cost estimating methodology provides flexibility for incorporating revisions to remedial alternatives and achieves the desired range of accuracy. It is important to note that the cost estimating methodology presented here was developed as a concurrent path to the development of contaminated media quantity estimates. This methodology can be initiated before contaminated media quantities are estimated. As a result, this methodology is useful in developing cost estimates for use in screening and evaluating remedial technologies and process options. However, remedial alternative cost estimates cannot be prepared without the contaminated media quantity estimates. In the conduct of the feasibility study for Operable Unit 5 at the Fernald Environmental Management Project (FEMP), fourteen remedial alternatives were retained for detailed analysis. Each remedial alternative was composed of combinations of remedial technologies and processes which were earlier determined to be best suited for addressing the media-specific contaminants found at the FEMP site, and achieving desired remedial action objectives

  4. Variation of uranium isotopes in some carbonate aquifers

    International Nuclear Information System (INIS)

    Cowart, J.B.

    1980-01-01

    The 234 U/ 238 U alpha activity ratio (AR) and uranium concentrations are reported for 83 springs that issue from carbonate aquifers in Florida, Texas, Nevada-California, and Israel. Data for each aquifer fall within more or less mutually exclusive fields. In general, the spring in a humid climate have AR's approaching secular equilibrium, whereas those in more arid climates have AR's differing greatly from equilibrium

  5. Drilling methods to keep the hydrogeological parameters of natural aquifer

    International Nuclear Information System (INIS)

    Chen Xiaoqin

    2004-01-01

    In hydrogeological drilling, how to keep the hydrogeological parameters of natural aquifer unchanged is a deeply concerned problem for the technicians, this paper introduces the methods taken by the state-owned 'Red Hill' geological company of Uzbekistan. By the research and contrast of different kinds of flush liquid, the company has found the methods to reduce the negative effects of drilling on the permeability of the vicinal aquifer. (author)

  6. FEWA: a Finite Element model of Water flow through Aquifers

    International Nuclear Information System (INIS)

    Yeh, G.T.; Huff, D.D.

    1983-11-01

    This report documents the implementation and demonstration of a Finite Element model of Water flow through Aquifers (FEWA). The particular features of FEWA are its versatility and flexibility to deal with as many real-world problems as possible. Point as well as distributed sources/sinks are included to represent recharges/pumpings and rainfall infiltrations. All sources/sinks can be transient or steady state. Prescribed hydraulic head on the Dirichlet boundaries and fluxes on Neumann or Cauchy boundaries can be time-dependent or constant. Source/sink strength over each element and node, hydraulic head at each Dirichlet boundary node, and flux at each boundary segment can vary independently of each other. Either completely confined or completely unconfined aquifers, or partially confined and partially unconfined aquifers can be dealt with effectively. Discretization of a compound region with very irregular curved boundaries is made easy by including both quadrilateral and triangular elements in the formulation. Large-field problems can be solved efficiently by including a pointwise iterative solution strategy as an optional alternative to the direct elimination solution method for the matrix equation approximating the partial differential equation of groundwater flow. FEWA also includes transient flow through confining leaky aquifers lying above and/or below the aquifer of interest. The model is verified against three simple cases to which analytical solutions are available. It is then demonstrated by two examples of how the model can be applied to heterogeneous and anisotropic aquifers with transient boundary conditions, time-dependent sources/sinks, and confining aquitards for a confined aquifer of variable thickness and for a free surface problem in an unconfined aquifer, respectively. 20 references, 25 figures, 8 tables

  7. Geoelectrical Characterization of Aquifer Precincts in Parts of Lapai ...

    African Journals Online (AJOL)

    Longitudinal conductance and transverse resistance calculated from the layers' thicknesses and resistivities varied from 0.00039Siemens to 2.05Siemens and 3.96×106 Ωm2 to 3.34×107Ωm2 respectively. The aquifer overburden protection capacity in VES 2, 5, 6,9,10 and 11 were relatively low which means the aquifer in ...

  8. Critical stress scenarios for a coastal aquifer in southeastern Italy

    Directory of Open Access Journals (Sweden)

    C. Cherubini

    2011-05-01

    Full Text Available Over the last years the sustainable management of coastal water resources has become strategic, especially in southern Salento Peninsula (Apulia, where mal-performing management strategies adopted, together with the vulnerability of the hydrogeological system, have given rise to the deterioration of groundwater quality due to saltwater intrusion.

    In the study area there is the presence of multilevel shallow aquifer and a deep aquifer that interact by means of faults. The geological system is highly vulnerable to seawater intrusion so there is the need to adopt management strategies to avoid seawater intrusion phenomena. Nevertheless there is a lack of studies that analyze the methodology for the correct exploitation if the water resource in order to avoid further intrusion phenomena.

    This paper combines a density-driven, flow numerical model (Seawat v.4 with a fault conceptual and hydrologic model to simulate saltwater intrusion phenomenon in the deep as well as in the shallow aquifer of the Salento area. By means of the individuation of an indicator parameter of groundwater quality, it has been possible to simulate different scenarios of exploitation and therefore to define critical stress scenarios for both aquifers.

    The results show that the deep aquifer is more vulnerable than the shallow one, which means that in the former, in order not to reach conditions of contamination, a lower density of wells is necessary than in the latter.

    The reduction of well density coupled with the artificial recharge of freshwater into the aquifer may be proposed as a solution strategy to protect the aquifer.

    Therefore, future developments of the present study will be represented by the simulation of different scenarios of recharging to inhibit the saltwater intrusion front further inland. The proposed methodology and its future developments can represent an empirical tool to provide preliminary guidelines for long

  9. Copper and zinc distribution coefficients for sandy aquifer materials

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Astrup, Thomas; Boddum, J. K.

    2000-01-01

    ; Zn: 6±22,800 l/kg) and correlating them to the characteristics of the aquifer material (particle size distribution, organic C content, surface area, pH) revealed good correlation with pH in the range 5.3± 8.9 (Cu: r 2=0.72; Zn: r 2=0.94). Including any other of the measured aquifer characteristics...

  10. In Situ Remediation of a TCE-Contaminated Aquifer Using a Short Rotation Woody Crop Groundwater Treatment System

    Science.gov (United States)

    2006-05-01

    groundwater RCRA Resource Conservation and Recovery Act SAIC Science Applications International Corporation SARA Superfund Amendments and...instrumental in making this project a success. Scientists at Science Applications International Corporation (SAIC), the University of Georgia, the...to a depth of 1 m. The whips or caliper trees were placed within the trenched rows along with irrigation lines. An agronomic assessment identified

  11. Remedial Investigation/Feasibility Study Work Plan for the 200-UP-1 Groundwater Operable Unit, Hanford Site, Richland, Washington. Revision

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    This work plan identifies the objectives, tasks, and schedule for conducting a Remedial Investigation/Feasibility Study for the 200-UP-1 Groundwater Operable Unit in the southern portion of the 200 West Groundwater Aggregate Area of the Hanford Site. The 200-UP-1 Groundwater Operable Unit addresses contamination identified in the aquifer soils and groundwater within its boundary, as determined in the 200 West Groundwater Aggregate Area Management Study Report (AAMSR) (DOE/RL 1992b). The objectives of this work plan are to develop a program to investigate groundwater contaminants in the southern portion of the 200 West Groundwater Aggregate Area that were designated for Limited Field Investigations (LFIs) and to implement Interim Remedial Measures (IRMs) recommended in the 200 West Groundwater AAMSR. The purpose of an LFI is to evaluate high priority groundwater contaminants where existing data are insufficient to determine whether an IRM is warranted and collect sufficient data to justify and implement an IRM, if needed. A Qualitative Risk Assessment (QRA) will be performed as part of the LFI. The purpose of an IRM is to develop and implement activities, such as contaminant source removal and groundwater treatment, that will ameliorate some of the more severe potential risks of groundwater contaminants prior to the RI and baseline Risk Assessment (RA) to be conducted under the Final Remedy Selection (FRS) at a later date. This work plan addresses needs of a Treatability Study to support the design and implementation of an interim remedial action for the Uranium-{sup 99}{Tc}-Nitrate multi-contaminant IRM plume identified beneath U Plant.

  12. Human enteric viruses in groundwater from a confined bedrock aquifer

    Science.gov (United States)

    Borchardt, M. A.; Bradbury, K.R.; Gotkowitz, M.B.; Cherry, J.A.; Parker, B.L.

    2007-01-01

    Confined aquifers are overlain by low-permeability aquitards that are commonly assumed to protect underlying aquifers from microbial contaminants. However, empirical data on microbial contamination beneath aquitards is limited. This study determined the occurrence of human pathogenic viruses in well water from a deep sandstone aquifer confined by a regionally extensive shale aquitard. Three public water-supply wells were each sampled 10 times over 15 months. Samples were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) for several virus groups and by cell culture for infectious enteroviruses. Seven of 30 samples were positive by RT-PCR for enteroviruses; one of these was positive for infectious echovirus 18. The virus-positive samples were collected from two wells cased through the aquitard, indicating the viruses were present in the confined aquifer. Samples from the same wells showed atmospheric tritium, indicating water recharged within the past few decades. Hydrogeologic conditions support rapid porous media transport of viruses through the upper sandstone aquifer to the top of the aquitard 61 m below ground surface. Natural fractures in the shale aquitard are one possible virus transport pathway through the aquitard; however, windows, cross-connecting well bores, or imperfect grout seals along well casings also may be involved. Deep confined aquifers can be more vulnerable to contamination by human viruses than commonly believed. ?? 2007 American Chemical Society.

  13. Sustainable Capture: Concepts for Managing Stream-Aquifer Systems.

    Science.gov (United States)

    Davids, Jeffrey C; Mehl, Steffen W

    2015-01-01

    Most surface water bodies (i.e., streams, lakes, etc.) are connected to the groundwater system to some degree so that changes to surface water bodies (either diversions or importations) can change flows in aquifer systems, and pumping from an aquifer can reduce discharge to, or induce additional recharge from streams, springs, and lakes. The timescales of these interactions are often very long (decades), making sustainable management of these systems difficult if relying only on observations of system responses. Instead, management scenarios are often analyzed based on numerical modeling. In this paper we propose a framework and metrics that can be used to relate the Theis concepts of capture to sustainable measures of stream-aquifer systems. We introduce four concepts: Sustainable Capture Fractions, Sustainable Capture Thresholds, Capture Efficiency, and Sustainable Groundwater Storage that can be used as the basis for developing metrics for sustainable management of stream-aquifer systems. We demonstrate their utility on a hypothetical stream-aquifer system where pumping captures both streamflow and discharge to phreatophytes at different amounts based on pumping location. In particular, Capture Efficiency (CE) can be easily understood by both scientists and non-scientist alike, and readily identifies vulnerabilities to sustainable stream-aquifer management when its value exceeds 100%. © 2014, National Ground Water Association.

  14. DOE In Situ Remediation Integrated Program

    International Nuclear Information System (INIS)

    Yow, J.L. Jr.

    1993-01-01

    The In Situ Remediation Integrated Program (ISRP) supports and manages a balanced portfolio of applied research and development activities in support of DOE environmental restoration and waste management needs. ISRP technologies are being developed in four areas: containment, chemical and physical treatment, in situ bioremediation, and in situ manipulation (including electrokinetics). the focus of containment is to provide mechanisms to stop contaminant migration through the subsurface. In situ bioremediation and chemical and physical treatment both aim to destroy or eliminate contaminants in groundwater and soils. In situ manipulation (ISM) provides mechanisms to access contaminants or introduce treatment agents into the soil, and includes other technologies necessary to support the implementation of ISR methods. Descriptions of each major program area are provided to set the technical context of the ISM subprogram. Typical ISM needs for major areas of in situ remediation research and development are identified

  15. The transdisciplinary potential of remediated painting

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    2011-01-01

    "The Transdisciplinary Potential of Remediated Painting" Over the last decades the notion of what painting is has been considerably widened due to intermediality, i.e. crossovers between artistic media such as painting and sculpture, painting and photography, painting and installation, painting...... and performance etc. This paper suggests that the transformation of the discipline of painting into an expanded field has not only liberated painting from its ties to its traditional repertoire of materials and modes of representation. It has also released a tremendous potential for image making that takes...... painting as a point of departure but moves beyond the limitations of dialogic intermedia into the field of transdisciplinary aesthetics. In support of my argument, I turn to the concept of remediation as it was first applied in new media theory by Jay David Bolter and Richard Grusin. The ambition...

  16. The role of innovative remediation technologies

    International Nuclear Information System (INIS)

    Doesburg, J.M.

    1992-05-01

    There are currently over 1200 sites on the US Superfund's National Priorities List (NPL) of hazardous waste sites, and there are over 30, 000 sites listed by the Comprehensive Environmental Responsibility, Compensation and Liability Information System (CERCLIS). The traditional approach to remediating sites in the US has been to remove the material and place it in a secure landfill, or in the case of groundwater, pump and treat the effluent. These technologies have proven to be very expensive and don't really fix the problem. The waste is just moved from one place to another. In recent years, however, alternative and innovative technologies have been increasingly used in the US to replace the traditional approaches. This paper will focus on just such innovative remediation technologies in the US, looking at the regulatory drivers, the emerging technologies, some of the problems in deploying technologies, and a case study

  17. Decommissioning and environmental remediation: An overview

    International Nuclear Information System (INIS)

    Chatzis, Irena

    2016-01-01

    The objective in both decommissioning and environmental remediation is to lower levels of residual radioactivity enough that the sites may be used for any purpose, without restriction. In some cases, however, this may not be practical and restrictions may be placed on future land use. Following decommissioning, for example, some sites may be reused for non-nuclear industrial activities, but not for habitation. Some former uranium mining sites may be released for reuse as nature reserves or for other leisure activities. Both decommissioning and environmental remediation are major industrial projects in which the safety of the workforce, the local public and the environment must be ensured from both radiological and conventional hazards. Hence, an appropriate legal and regulatory framework, as well as proper training for personnel both in implementation and in regulatory oversight are among the necessary preconditions to ensure safety.

  18. Decommissioning and environmental remediation: An overview

    International Nuclear Information System (INIS)

    Chatzis, Irena

    2016-01-01

    The objective in both decommissioning and environmental remediation is to lower levels of residual radioactivity enough that the sites may be used for any purpose, without restriction. In some cases, however, this may not be practical and restrictions may be placed on future land use. Following decommissioning, for example, some sites may be reused for non-nuclear industrial activities, but not for habitation. Some former uranium mining sites may be released for reuse as nature reserves or for other leisure activities. Both decommissioning and environmental remediation are major industrial projects in which the safety of the workforce, the local public and the environment must be ensured from both radiological and conventional hazards. Hence, an appropriate legal and regulatory framework, as well as proper training for personnel both in implementation and in regulatory oversight are among the necessary preconditions to ensure safety

  19. Analytical considerations for stress related remedies

    International Nuclear Information System (INIS)

    Rybicki, E.F.; McGuire, P.A.

    1984-01-01

    The study described here focuses on reducing the impact of one of the factors, contributing to integranular stress corrosion cracking (IGSCC) in BWR reactor piping, e.g., tensile residual stresses in the areas of observed cracking. There are several techniques for controlling residual stresses on the inside surface of girth welded pipes. The work described here is part of a larger study where various remedies and pipe geometries were considered. The stress remedy technique utilizes an induction heating method to alter residual stresses due to welding. The method is referred to as Induction Heating for Stress Improvement (IHSI). While IHSI was first applied to pipe-to-pipe weldments with successful results, many field applications of IHSI will be to pipe-to-tee or pipe-to-component geometries. Therefore, this study is directed toward obtaining a better understanding of the weld induced residual stress and the effect of IHSI on weldments with this type of geometry

  20. The role of innovative remediation technologies

    Energy Technology Data Exchange (ETDEWEB)

    Doesburg, J.M.

    1992-05-01

    There are currently over 1200 sites on the US Superfund's National Priorities List (NPL) of hazardous waste sites, and there are over 30, 000 sites listed by the Comprehensive Environmental Responsibility, Compensation and Liability Information System (CERCLIS). The traditional approach to remediating sites in the US has been to remove the material and place it in a secure landfill, or in the case of groundwater, pump and treat the effluent. These technologies have proven to be very expensive and don't really fix the problem. The waste is just moved from one place to another. In recent years, however, alternative and innovative technologies have been increasingly used in the US to replace the traditional approaches. This paper will focus on just such innovative remediation technologies in the US, looking at the regulatory drivers, the emerging technologies, some of the problems in deploying technologies, and a case study.

  1. The role of innovative remediation technologies

    Energy Technology Data Exchange (ETDEWEB)

    Doesburg, J.M.

    1992-05-01

    There are currently over 1200 sites on the US Superfund`s National Priorities List (NPL) of hazardous waste sites, and there are over 30, 000 sites listed by the Comprehensive Environmental Responsibility, Compensation and Liability Information System (CERCLIS). The traditional approach to remediating sites in the US has been to remove the material and place it in a secure landfill, or in the case of groundwater, pump and treat the effluent. These technologies have proven to be very expensive and don`t really fix the problem. The waste is just moved from one place to another. In recent years, however, alternative and innovative technologies have been increasingly used in the US to replace the traditional approaches. This paper will focus on just such innovative remediation technologies in the US, looking at the regulatory drivers, the emerging technologies, some of the problems in deploying technologies, and a case study.

  2. Armored Enzyme Nanoparticles for Remediation of Subsurface

    Energy Technology Data Exchange (ETDEWEB)

    Grate, Jay W.

    2005-09-01

    The remediation of subsurface contaminants is a critical problem for the Department of Energy, other government agencies, and our nation. Severe contamination of soil and groundwater exists at several DOE sites due to various methods of intentional and unintentional release. Given the difficulties involved in conventional removal or separation processes, it is vital to develop methods to transform contaminants and contaminated earth/water to reduce risks to human health and the environment. Transformation of the contaminants themselves may involve conversion to other immobile species that do not migrate into well water or surface waters, as is proposed for metals and radionuclides; or degradation to harmless molecules, as is desired for organic contaminants. Transformation of contaminated earth (as opposed to the contaminants themselves) may entail reductions in volume or release of bound contaminants for remediation.

  3. Remediating sites contaminated with heavy metals

    International Nuclear Information System (INIS)

    Swartzbaugh, J.; Sturgill, J.; Cormier, B.; Williams, H.D.

    1992-01-01

    This article is intended to serve as a reference for decision makers who must choose an approach to remediate sites contaminated with heavy metals. Its purpose is to explain pertinent chemical and physical characteristics of heavy metals, how to use these characteristics to select remedial technologies, and how to interpret and use data from field investigations. Different metal species are typically associated with different industrial processes. The contaminant species behave differently in various media (i.e., groundwater, soils, air), and require different technologies for containment and treatment. We focus on the metals that are used in industries that generate regulated waste. These include steelmaking, paint and pigment manufacturing, metal finishing, leather tanning, papermaking, aluminum anodizing, and battery manufacturing. Heavy metals are also present in refinery wastes as well as in smelting wastes and drilling muds

  4. Briefing paper -- Remedial Action Assessment System

    Energy Technology Data Exchange (ETDEWEB)

    Buelt, J.L.

    1990-04-01

    Congress has mandated a more comprehensive management of hazardous wastes with the Resource Conservation and Recovery Act (RCRA), the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA or Superfund'') and the Superfund Amendment and Reauthorization Act (SARA). This mandate includes restoration of disposal sites contaminated through past disposal practices. This mandate applies to facilities operated for and by the Department of Energy (DOE), just as it does to industrial and other institutions. To help implement the CERCLA/SARA remedial investigation and feasibility study (RI/FS) process in a consistent, timely, and cost-effective manner, a methodology needs to be developed that will allow definition, sorting, and screening of remediation technologies for each operable unit (waste site). This need is stated specifically in Section 2.2.2.1 of the October 1989 Applied Research, Development, Demonstration, Testing, and Evaluation (RDDT E) Plan of the DOE. This Briefing Paper is prepared to respond to this need. 1 fig.

  5. Soil and ground-water remediation techniques

    International Nuclear Information System (INIS)

    Beck, P.

    1996-01-01

    Urban areas typically contain numerous sites underlain by soils or ground waters which are contaminated to levels that exceed clean-up guidelines and are hazardous to public health. Contamination most commonly results from the disposal, careless use and spillage of chemicals, or the historic importation of contaminated fill onto properties undergoing redevelopment. Contaminants of concern in soil and ground water include: inorganic chemicals such as heavy metals; radioactive metals; salt and inorganic pesticides, and a range of organic chemicals included within petroleum fuels, coal tar products, PCB oils, chlorinated solvents, and pesticides. Dealing with contaminated sites is a major problem affecting all urban areas and a wide range of different remedial technologies are available. This chapter reviews the more commonly used methods for ground-water and soil remediation, paying particular regard to efficiency and applicability of specific treatments to different site conditions. (author). 43 refs., 1 tab., 27 figs

  6. Briefing paper -- Remedial Action Assessment System

    International Nuclear Information System (INIS)

    Buelt, J.L.

    1990-04-01

    Congress has mandated a more comprehensive management of hazardous wastes with the Resource Conservation and Recovery Act (RCRA), the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA or ''Superfund'') and the Superfund Amendment and Reauthorization Act (SARA). This mandate includes restoration of disposal sites contaminated through past disposal practices. This mandate applies to facilities operated for and by the Department of Energy (DOE), just as it does to industrial and other institutions. To help implement the CERCLA/SARA remedial investigation and feasibility study (RI/FS) process in a consistent, timely, and cost-effective manner, a methodology needs to be developed that will allow definition, sorting, and screening of remediation technologies for each operable unit (waste site). This need is stated specifically in Section 2.2.2.1 of the October 1989 Applied Research, Development, Demonstration, Testing, and Evaluation (RDDT ampersand E) Plan of the DOE. This Briefing Paper is prepared to respond to this need. 1 fig

  7. Radioactive tank waste remediation focus area

    International Nuclear Information System (INIS)

    1996-08-01

    EM's Office of Science and Technology has established the Tank Focus Area (TFA) to manage and carry out an integrated national program of technology development for tank waste remediation. The TFA is responsible for the development, testing, evaluation, and deployment of remediation technologies within a system architecture to characterize, retrieve, treat, concentrate, and dispose of radioactive waste stored in the underground stabilize and close the tanks. The goal is to provide safe and cost-effective solutions that are acceptable to both the public and regulators. Within the DOE complex, 335 underground storage tanks have been used to process and store radioactive and chemical mixed waste generated from weapon materials production and manufacturing. Collectively, thes tanks hold over 90 million gallons of high-level and low-level radioactive liquid waste in sludge, saltcake, and as supernate and vapor. Very little has been treated and/or disposed or in final form

  8. The transdisciplinary potential of remediated painting

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    2011-01-01

    "The Transdisciplinary Potential of Remediated Painting" Over the last decades the notion of what painting is has been considerably widened due to intermediality, i.e. crossovers between artistic media such as painting and sculpture, painting and photography, painting and installation, painting...... painting as a point of departure but moves beyond the limitations of dialogic intermedia into the field of transdisciplinary aesthetics. In support of my argument, I turn to the concept of remediation as it was first applied in new media theory by Jay David Bolter and Richard Grusin. The ambition...... that starts from the transdisciplinary potential of painting instead of its historical disciplinarity and the attendant assumption that, as a discipline, painting functions independently and establishes its own separate space of cultural meaning. Secondly, it defines painting as active, performative...

  9. ELECTROKINETIC REMEDIATION STUDY FOR CADMIUM CONTAMINATED SOIL

    Directory of Open Access Journals (Sweden)

    P. Bala Ramudu

    2007-09-01

    Full Text Available This paper presents the results of an experimental research undertaken to evaluate different purging solutions to enhance the removal of cadmium from spiked contaminated field soil by electrokinetic remediation. Three experiments were conducted when soil was saturated with deionised water and subsequently deionised water, ammonium citrate and sodium citrate were used as purging solutions at anode end. One experiment was conducted when the soil was saturated with ammonium citrate and itself was used as the purging solution. Results showed that 49% reduction of cadmium concentration was achieved in the case of soil saturated (washed with ammonium citrate as well as purging solution also was ammonium citrate. The soil pH and washing solutions were the most important factors in controlling the removal of cadmium in electrokinetic remediation process.

  10. Estimates Of Radiation Belt Remediation Requirements

    Science.gov (United States)

    Tuszewski, M.; Hoyt, R. P.; Minor, B. M.

    2004-12-01

    A low-Earth orbit nuclear detonation could produce an intense artificial radiation belt of relativistic electrons. Many satellites would be destroyed within a few weeks. We present here simple estimates of radiation belt remediation by several different techniques, including electron absorption by gas release, pitch angle scattering by steady electric and magnetic fields from tether arrays, and pitch angle scattering by wave-particle interactions from in-situ transmitters. For each technique, the mass, size, and power requirements are estimated for a one-week remediation (e-folding) timescale, assuming that a 10 kTon blast trapped 1024 fission product electrons (1 to 8 MeV) at L = 1.5 in a dipolar belt of width dL = 0.1.

  11. Independent Technical Review of the X-740 Groundwater Remedy, Portsmouth, Ohio: Technical Evaluation and Recommendations

    International Nuclear Information System (INIS)

    Looney, B.; Rhia, B.; Jackson, D.; Eddy-Dilek, C.

    2010-01-01

    Two major remedial campaigns have been applied to a plume of trichloroethene (TCE) contaminated groundwater near the former X-740 facility at the Portsmouth Gaseous Diffusion Plant in Piketon Ohio. The two selected technologies, phytoremediation using a stand of hybrid poplar trees from 1999-2007 and in situ chemical oxidation using modified Fenton's Reagent from 2008-2009, have proven ineffective in achieving remedial action objectives (RAOs). The 'poor' performance of these technologies is a direct result of site specific conditions and the local contaminant hydrogeology. Key among these challenges is the highly heterogeneous subsurface geology with a thin contaminated aquifer zone (the Gallia) - the behavior of the contamination in the Gallia is currently dominated by slow release of TCE from the clay of the overlying Minford formation, from the sandstone of the underlying Berea formation, and from clayey layers within the Gallia itself. In response to the remediation challenges for the X-740 plume, the Portsmouth team (including the US Department of Energy (DOE), the site contractor (CDM), and the Ohio Environmental Protection Agency (OEPA)) is evaluating the feasibility of remediation at this site and identifying specific alternatives that are well matched to site conditions and that would maximize the potential for achieving RAOs. To support this evaluation, the DOE Office of Groundwater and Soil Remediation (EM-32) assembled a team of experts to serve as a resource and provide input and recommendations to Portsmouth. Despite the challenging site conditions and the failure of the previous two remediation campaigns to adequately move the site toward RAOs, the review team was unanimous in the conclusion that an effective combination of cost effective technologies can be identified. Further, the team expressed optimism that RAOs can be achieved if realistic timeframes are accepted by all parties. The initial efforts of the review team focused on reviewing the

  12. Independent Technical Review of the X-740 Groundwater Remedy, Portsmouth, Ohio: Technical Evaluation and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Looney, B.; Rhia, B.; Jackson, D.; Eddy-Dilek, C.

    2010-04-30

    Two major remedial campaigns have been applied to a plume of trichloroethene (TCE) contaminated groundwater near the former X-740 facility at the Portsmouth Gaseous Diffusion Plant in Piketon Ohio. The two selected technologies, phytoremediation using a stand of hybrid poplar trees from 1999-2007 and in situ chemical oxidation using modified Fenton's Reagent from 2008-2009, have proven ineffective in achieving remedial action objectives (RAOs). The 'poor' performance of these technologies is a direct result of site specific conditions and the local contaminant hydrogeology. Key among these challenges is the highly heterogeneous subsurface geology with a thin contaminated aquifer zone (the Gallia) - the behavior of the contamination in the Gallia is currently dominated by slow release of TCE from the clay of the overlying Minford formation, from the sandstone of the underlying Berea formation, and from clayey layers within the Gallia itself. In response to the remediation challenges for the X-740 plume, the Portsmouth team (including the US Department of Energy (DOE), the site contractor (CDM), and the Ohio Environmental Protection Agency (OEPA)) is evaluating the feasibility of remediation at this site and identifying specific alternatives that are well matched to site conditions and that would maximize the potential for achieving RAOs. To support this evaluation, the DOE Office of Groundwater and Soil Remediation (EM-32) assembled a team of experts to serve as a resource and provide input and recommendations to Portsmouth. Despite the challenging site conditions and the failure of the previous two remediation campaigns to adequately move the site toward RAOs, the review team was unanimous in the conclusion that an effective combination of cost effective technologies can be identified. Further, the team expressed optimism that RAOs can be achieved if realistic timeframes are accepted by all parties. The initial efforts of the review team focused on

  13. Potentiometric-surface altitude of the confined aquifer, Wood River Valley aquifer system, south-central Idaho, October 2012.

    Data.gov (United States)

    Department of the Interior — Water levels in 93 wells completed in the Wood River Valley aquifer system were measured during October 22–24, 2012; these wells are part of a network established...

  14. Water-table altitude of the unconfined aquifer, Wood River Valley aquifer system, south-central Idaho, October 2012.

    Data.gov (United States)

    Department of the Interior — Water levels in 93 wells completed in the Wood River Valley aquifer system were measured during October 22–24, 2012; these wells are part of a network established...

  15. Geophysical Signitures From Hydrocarbon Contaminated Aquifers

    Science.gov (United States)

    Abbas, M.; Jardani, A.

    2015-12-01

    The task of delineating the contamination plumes as well as studying their impact on the soil and groundwater biogeochemical properties is needed to support the remediation efforts and plans. Geophysical methods including electrical resistivity tomography (ERT), induced polarization (IP), ground penetrating radar (GPR), and self-potential (SP) have been previously used to characterize contaminant plumes and investigate their impact on soil and groundwater properties (Atekwana et al., 2002, 2004; Benson et al., 1997; Campbell et al., 1996; Cassidy et al., 2001; Revil et al., 2003; Werkema et al., 2000). Our objective was to: estimate the hydrocarbon contamination extent in a contaminated site in northern France, and to adverse the effects of the oil spill on the groundwater properties. We aim to find a good combination of non-intrusive and low cost methods which we can use to follow the bio-remediation process, which is planned to proceed next year. We used four geophysical methods including electrical resistivity tomography, IP, GPR, and SP. The geophysical data was compared to geochemical ones obtained from 30 boreholes installed in the site during the geophysical surveys. Our results have shown: low electrical resistivity values; high chargeability values; negative SP anomalies; and attenuated GPR reflections coincident with groundwater contamination. Laboratory and field geochemical measurements have demonstrated increased groundwater electrical conductivity and increased microbial activity associated with hydrocarbon contamination of groundwater. Our study results support the conductive model suggested by studies such as Sauck (2000) and Atekwana et al., (2004), who suggest that biological alterations of hydrocarbon contamination can substantially modify the chemical and physical properties of the subsurface, producing a dramatic shift in the geo-electrical signature from resistive to conductive. The next stage of the research will include time lapse borehole

  16. Remedial approaches to students with discalculia

    OpenAIRE

    MATĚJKOVÁ, Daniela

    2011-01-01

    Thesis: "Remedial approaches to students with discalculia" defines the term of specific learning disability, individual specific learning disabilities with an emphasis on discalculia (mathematics disorder). It gives a brief overview of the methods, forms, aids (tools), individual re-education practices and affects the possibilities to integrate these students into current elementary school. The practical part deals with the integration of dyscalculia students into the teaching process and to ...

  17. Tank waste remediation system mission analysis report

    International Nuclear Information System (INIS)

    Acree, C.D.

    1998-01-01

    This document describes and analyzes the technical requirements that the Tank Waste Remediation System (TWRS) must satisfy for the mission. This document further defines the technical requirements that TWRS must satisfy to supply feed to the private contractors' facilities and to store or dispose the immobilized waste following processing in these facilities. This document uses a two phased approach to the analysis to reflect the two-phased nature of the mission

  18. Remedial action programs annual meeting: Meeting notes

    International Nuclear Information System (INIS)

    1987-01-01

    The US Department of Energy Grand Junction Projects Office was pleased to host the 1987 Remedial Action programs Annual Meeting and herein presents notes from that meeting as prepared (on relatively short notice) by participants. These notes are a summary of the information derived from the workshops, case studies, and ad hoc committee reports rather than formal proceedings. The order of the materials in this report follows the actual sequence of presentations during the annual meeting

  19. Cultural services remediated in Second Life

    DEFF Research Database (Denmark)

    Heilesen, Simon

    2008-01-01

    In 2007, the Danish Public Libraries conducted an experiment in establishing a library in the virtual world Second Life. The Info Island DK provided the framework for a number of online library services and cultural events. This study, based on interviews with most of the active participants in t...... in the project, discusses the experiences in remediating conventional library services into the new medium and in understanding and redefining the role of the librarian in an online virtual world....

  20. Groundwater remediation at the Hanford site

    International Nuclear Information System (INIS)

    Fries, W.

    1993-01-01

    Ion exchange resin and adsorption technology has been used successfully to treat diversified types of toxic waste water for many years. Even though the Hanford Site presents many unique problems, the author believes these technologies can remediate the groundwater at this site. However, treatment of the sludge in tanks generally is beyond the pale of these technologies except for the possibility of experimental studies being performed at the University of Idaho (Troescher)

  1. Tank waste remediation system mission analysis report

    Energy Technology Data Exchange (ETDEWEB)

    Acree, C.D.

    1998-01-09

    This document describes and analyzes the technical requirements that the Tank Waste Remediation System (TWRS) must satisfy for the mission. This document further defines the technical requirements that TWRS must satisfy to supply feed to the private contractors` facilities and to store or dispose the immobilized waste following processing in these facilities. This document uses a two phased approach to the analysis to reflect the two-phased nature of the mission.

  2. Arsenic control during aquifer storage recovery cycle tests in the Floridan Aquifer.

    Science.gov (United States)

    Mirecki, June E; Bennett, Michael W; López-Baláez, Marie C

    2013-01-01

    Implementation of aquifer storage recovery (ASR) for water resource management in Florida is impeded by arsenic mobilization. Arsenic, released by pyrite oxidation during the recharge phase, sometimes results in groundwater concentrations that exceed the 10 µg/L criterion defined in the Safe Drinking Water Act. ASR was proposed as a major storage component for the Comprehensive Everglades Restoration Plan (CERP), in which excess surface water is stored during the wet season, and then distributed during the dry season for ecosystem restoration. To evaluate ASR system performance for CERP goals, three cycle tests were conducted, with extensive water-quality monitoring in the Upper Floridan Aquifer (UFA) at the Kissimmee River ASR (KRASR) pilot system. During each cycle test, redox evolution from sub-oxic to sulfate-reducing conditions occurs in the UFA storage zone, as indicated by decreasing Fe(2+) /H2 S mass ratios. Arsenic, released by pyrite oxidation during recharge, is sequestered during storage and recovery by co-precipitation with iron sulfide. Mineral saturation indices indicate that amorphous iron oxide (a sorption surface for arsenic) is stable only during oxic and sub-oxic conditions of the recharge phase, but iron sulfide (which co-precipitates arsenic) is stable during the sulfate-reducing conditions of the storage and recovery phases. Resultant arsenic concentrations in recovered water are below the 10 µg/L regulatory criterion during cycle tests 2 and 3. The arsenic sequestration process is appropriate for other ASR systems that recharge treated surface water into a sulfate-reducing aquifer. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

  3. Innovative technologies for in-situ remediation

    International Nuclear Information System (INIS)

    Ragaini, R.; Aines, R.; Knapp, R.; Matthews, S.; Yow, J.

    1994-06-01

    LLNL is developing several innovative remediation technologies as long-term improvements to the current pump and treat approaches to cleaning up contaminated soils and groundwater. These technologies include dynamic underground stripping, in-situ microbial filters, and remediation using bremsstrahlung radiation. Concentrated underground organic contaminant plumes are one of the most prevalent groundwater contamination sources. The solvent or fuel can percolate deep into the earth, often into water-bearing regions. Collecting as a separate, liquid organic phase called dense non-aqueous-phase liquids (DNAPLs), or light NAPLs (LNAPLs), these contaminants provide a source term that continuously compromises surrounding groundwater. This type of spill is one of the most difficult environmental problems to remediate. Attempts to remove such material requires a huge amount of water which must be washed through the system to clean it, requiring decades. Traditional pump and treat approaches have not been successful. LLNL has developed several innovative technologies to clean up NAPL contamination. Detailed descriptions of these technologies are given

  4. Methodology to remediate a mixed waste site

    Energy Technology Data Exchange (ETDEWEB)

    Berry, J.B.

    1994-08-01

    In response to the need for a comprehensive and consistent approach to the complex issue of mixed waste management, a generalized methodology for remediation of a mixed waste site has been developed. The methodology is based on requirements set forth in the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Resource Conservation and Recovery Act (RCRA) and incorporates ``lessons learned`` from process design, remediation methodologies, and remediation projects. The methodology is applied to the treatment of 32,000 drums of mixed waste sludge at the Oak Ridge K-25 Site. Process technology options are developed and evaluated, first with regard to meeting system requirements and then with regard to CERCLA performance criteria. The following process technology options are investigated: (1) no action, (2) separation of hazardous and radioactive species, (3) dewatering, (4) drying, and (5) solidification/stabilization. The first two options were eliminated from detailed consideration because they did not meet the system requirements. A quantitative evaluation clearly showed that, based on system constraints and project objectives, either dewatering or drying the mixed waste sludge was superior to the solidification/stabilization process option. The ultimate choice between the drying and the dewatering options will be made on the basis of a technical evaluation of the relative merits of proposals submitted by potential subcontractors.

  5. Preliminary remediation goals for ecological endpoints

    International Nuclear Information System (INIS)

    Efroymson, R.A.; Suter, G.W. II; Sample, B.E.; Jones, D.S.

    1996-07-01

    Preliminary remediation goals (PRGs) are useful for risk assessment and decision making at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) sites. PRGs are upper concentration limits for specific chemicals in specific environmental media that are anticipated to protect human health or the environment. They can be used for multiple remedial investigations at multiple facilities. In addition to media and chemicals of potential concern, the development of PRGs generally requires some knowledge or anticipation of future land use. In Preliminary Remediation Goals for Use at the U.S. Department of Energy Oak Ridge Operations Office (Energy Systems 1995), PRGs intended to protect human health were developed with guidance from Risk Assessment Guidance for Superfund: Volume I - Human Health Evaluation Manual, Part B (RAGS) (EPA 1991). However, no guidance was given for PRGs based on ecological risk. The numbers that appear in this volume have, for the most part, been extracted from toxicological benchmarks documents for Oak Ridge National Laboratory (ORNL) and have previously been developed by ORNL. The sources of the quantities, and many of the uncertainties associated with their derivation, are described in this technical memorandum

  6. Preliminary remediation goals for ecological endpoints

    Energy Technology Data Exchange (ETDEWEB)

    Efroymson, R.A.; Suter, G.W. II; Sample, B.E.; Jones, D.S.

    1996-07-01

    Preliminary remediation goals (PRGs) are useful for risk assessment and decision making at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) sites. PRGs are upper concentration limits for specific chemicals in specific environmental media that are anticipated to protect human health or the environment. They can be used for multiple remedial investigations at multiple facilities. In addition to media and chemicals of potential concern, the development of PRGs generally requires some knowledge or anticipation of future land use. In Preliminary Remediation Goals for Use at the U.S. Department of Energy Oak Ridge Operations Office (Energy Systems 1995), PRGs intended to protect human health were developed with guidance from Risk Assessment Guidance for Superfund: Volume I - Human Health Evaluation Manual, Part B (RAGS) (EPA 1991). However, no guidance was given for PRGs based on ecological risk. The numbers that appear in this volume have, for the most part, been extracted from toxicological benchmarks documents for Oak Ridge National Laboratory (ORNL) and have previously been developed by ORNL. The sources of the quantities, and many of the uncertainties associated with their derivation, are described in this technical memorandum.

  7. Tank waste remediation system configuration management plan

    International Nuclear Information System (INIS)

    Vann, J.M.

    1998-01-01

    The configuration management program for the Tank Waste Remediation System (TWRS) Project Mission supports management of the project baseline by providing the mechanisms to identify, document, and control the functional and physical characteristics of the products. This document is one of the tools used to develop and control the mission and work. It is an integrated approach for control of technical, cost, schedule, and administrative information necessary to manage the configurations for the TWRS Project Mission. Configuration management focuses on five principal activities: configuration management system management, configuration identification, configuration status accounting, change control, and configuration management assessments. TWRS Project personnel must execute work in a controlled fashion. Work must be performed by verbatim use of authorized and released technical information and documentation. Application of configuration management will be consistently applied across all TWRS Project activities and assessed accordingly. The Project Hanford Management Contract (PHMC) configuration management requirements are prescribed in HNF-MP-013, Configuration Management Plan (FDH 1997a). This TWRS Configuration Management Plan (CMP) implements those requirements and supersedes the Tank Waste Remediation System Configuration Management Program Plan described in Vann, 1996. HNF-SD-WM-CM-014, Tank Waste Remediation System Configuration Management Implementation Plan (Vann, 1997) will be revised to implement the requirements of this plan. This plan provides the responsibilities, actions and tools necessary to implement the requirements as defined in the above referenced documents

  8. Methodology to remediate a mixed waste site

    International Nuclear Information System (INIS)

    Berry, J.B.

    1994-08-01

    In response to the need for a comprehensive and consistent approach to the complex issue of mixed waste management, a generalized methodology for remediation of a mixed waste site has been developed. The methodology is based on requirements set forth in the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Resource Conservation and Recovery Act (RCRA) and incorporates ''lessons learned'' from process design, remediation methodologies, and remediation projects. The methodology is applied to the treatment of 32,000 drums of mixed waste sludge at the Oak Ridge K-25 Site. Process technology options are developed and evaluated, first with regard to meeting system requirements and then with regard to CERCLA performance criteria. The following process technology options are investigated: (1) no action, (2) separation of hazardous and radioactive species, (3) dewatering, (4) drying, and (5) solidification/stabilization. The first two options were eliminated from detailed consideration because they did not meet the system requirements. A quantitative evaluation clearly showed that, based on system constraints and project objectives, either dewatering or drying the mixed waste sludge was superior to the solidification/stabilization process option. The ultimate choice between the drying and the dewatering options will be made on the basis of a technical evaluation of the relative merits of proposals submitted by potential subcontractors

  9. Intersectionalities of Gender Violence: Legal Remedies: Editorial

    Directory of Open Access Journals (Sweden)

    Julie Goldscheid

    2015-12-01

    Full Text Available Critiques of legal remedies’ capacity adequately to address the intersectional nature of gender violence lie at the heart of both theoretical and practical discourse. Concern about remedies complements the important literature detailing the narrative experiences of those who experience violence grounded in multiple intersections of identity. This is an introduction to a set of papers that represent highlights from the conference entitled “International Congress on Gender Violence: Intersectionalities”. The papers address approaches to legal remedies that take into account the intersectional nature of gender violence. Las críticas a la capacidad de los remedies legales para abordar la naturaleza interseccional de la violencia de género están en el centro del discurso teórico y práctico. La preocupación sobre los remedios complementa la importante literatura que detalla las experiencias narrativas de las personas que experimentan violencia alojada en múltiples intersecciones de identidad. Esta es una introducción a artículos representativos del Congreso Internacional sobre Violencia de Género: Intersecciones. Los artículos abordan un acercamiento a los remedios legales que tienen en cuenta la naturaleza interseccional de la violencia de género. DOWNLOAD THIS PAPER FROM SSRN: http://ssrn.com/abstract=2710535

  10. Laboratory/industry partnerships for environmental remediation

    International Nuclear Information System (INIS)

    Beskid, N.J.; Zussman, S.K.

    1994-01-01

    There are two measures of ''successful'' technology transfer in DOE's environmental restoration and waste management program. The first is remediation of DOE sites, and the second is commercialization of an environmental remediation process or product. The ideal case merges these two in laboratory/industry partnerships for environmental remediation. The elements to be discussed in terms of their effectiveness in aiding technology transfer include: a decision-making champion; timely and sufficient funding; well organized technology transfer function; well defined DOE and commercial markets; and industry/commercial partnering. Several case studies are presented, including the successful commercialization of a process for vitrification of low-level radioactive waste, the commercial marketing of software for hazardous waste characterization, and the application of a monitoring technique that has won a prestigious technical award. Case studies will include: vitrification of low-level radioactive waste (GTS Duratek, Columbia, MD); borehole liner for emplacing instrumentation and sampling groundwater (Science and Engineering Associates, Inc., Santa Fe, NM); electronic cone penetrometer (Applied Research Associates, Inc., South Royalton, VT); and software for hazardous waste monitoring ConSolve, Inc. (Lexington, MA). The roles of the Department of Energy and Argonne National Laboratory in these successes will be characterized

  11. Geochemical processes in a calcareous sandstone aquifer during managed aquifer recharge with desalinated seawater

    Science.gov (United States)

    Ganot, Yonatan; Russak, Amos; Siebner, Hagar; Bernstein, Anat; Katz, Yoram; Guttman, Jospeh; Kurtzman, Daniel

    2017-04-01

    In the last three years we monitor Managed Aquifer Recharge (MAR) of post-treated desalinated seawater (PTDES) in an infiltration pond, at the Menashe site that overlies the northern part of the Israeli Coastal Aquifer. The PTDES are stabilized with CaCO3 during post-treatment in the desalination plant and their chemical composition differs from those of any other water recharged to the aquifer and of the natural groundwater. We use suction cups in the unsaturated zone, shallow observation wells within the pond and production wells that encircles the MAR Menashe site, to study the geochemical processes during MAR with PTDES. Ion-enrichment (remineralization) of the recharged water was observed in both unsaturated zone and shallow observation wells samples. Enrichment occurs mainly in the first few meters below the pond surface by ion-exchange processes. Mg2+ enrichment is most prominent due to its deficiency in the PTDES. It is explained by ion-exchange with Ca2+, as the PTDES (enriched with Ca2+) infiltrates through a calcareous-sandstone aquifer with various amount of adsorbed Mg2+ (3-27 meq/kg). Hence, the higher concentration of Ca+2 in the PTDES together with its higher affinity to the sediments promotes the release of Mg2+ ions to the recharged water. Water isotopes analysis of the production wells were used to estimate residence time and mixing with local groundwater. At the end of 2016, it was found that the percentage of PTDES in adjacent down-gradient production wells was around 10%, while more distant or up-gradient wells show no mixing with PTDES. The distinct isotope contrast between the recharged desalinated seawater (δ2H=+11.2±0.2‰) and the local groundwater (δ2H ranged from -22.7 to -16.7‰) is a promising tool to evaluate future mixing processes at the Menshae MAR site. Using the Menashe MAR system for remineralization could be beneficial as a primary or complementary post-treatment technique. However, the sustainability of this process is

  12. System-Scale Model of Aquifer, Vadose Zone, and River Interactions for the Hanford 300 Area - Application to Uranium Reactive Transport

    Energy Technology Data Exchange (ETDEWEB)

    Rockhold, Mark L.; Bacon, Diana H.; Freedman, Vicky L.; Parker, Kyle R.; Waichler, Scott R.; Williams, Mark D.

    2013-10-01

    This report represents a synthesis and integration of basic and applied research into a system-scale model of the Hanford 300 Area groundwater uranium plume, supported by the U.S. Department of Energy’s Richland Operations (DOE-RL) office. The report integrates research findings and data from DOE Office of Science (DOE-SC), Office of Environmental Management (DOE-EM), and DOE-RL projects, and from the site remediation and closure contractor, Washington Closure Hanford, LLC (WCH). The three-dimensional, system-scale model addresses water flow and reactive transport of uranium for the coupled vadose zone, unconfined aquifer, and Columbia River shoreline of the Hanford 300 Area. The system-scale model of the 300 Area was developed to be a decision-support tool to evaluate processes of the total system affecting the groundwater uranium plume. The model can also be used to address “what if” questions regarding different remediation endpoints, and to assist in design and evaluation of field remediation efforts. For example, the proposed cleanup plan for the Hanford 300 Area includes removal, treatment, and disposal of contaminated sediments from known waste sites, enhanced attenuation of uranium hot spots in the vadose and periodically rewetted zone, and continued monitoring of groundwater with institutional controls. Illustrative simulations of polyphosphate infiltration were performed to demonstrate the ability of the system-scale model to address these types of questions. The use of this model in conjunction with continued field monitoring is expected to provide a rigorous basis for developing operational strategies for field remediation and for defining defensible remediation endpoints.

  13. High-density PhyloChip profiling of stimulated aquifer microbial communities reveals a complex response to acetate amendment.

    Science.gov (United States)

    Handley, Kim M; Wrighton, Kelly C; Piceno, Yvette M; Andersen, Gary L; DeSantis, Todd Z; Williams, Kenneth H; Wilkins, Michael J; N'Guessan, A Lucie; Peacock, Aaron; Bargar, John; Long, Philip E; Banfield, Jillian F

    2012-07-01

    There is increasing interest in harnessing the functional capacities of indigenous microbial communities to transform and remediate a wide range of environmental contaminants. Information about which community members respond to stimulation can guide the interpretation and development of remediation approaches. To comprehensively determine community membership and abundance patterns among a suite of samples associated with uranium bioremediation experiments, we employed a high-density microarray (PhyloChip). Samples were unstimulated, naturally reducing, or collected during Fe(III) (early) and sulfate reduction (late biostimulation) from an acetate re-amended/amended aquifer in Rifle, Colorado, and from laboratory experiments using field-collected materials. Deep community sampling with PhyloChip identified hundreds-to-thousands of operational taxonomic units (OTUs) present during amendment, and revealed close similarity among highly enriched taxa from drill core and groundwater well-deployed column sediment. Overall, phylogenetic data suggested that stimulated community membership was most affected by a carryover effect between annual stimulation events. Nevertheless, OTUs within the Fe(III)- and sulfate-reducing lineages, Desulfuromonadales and Desulfobacterales, were repeatedly stimulated. Less consistent, co-enriched taxa represented additional lineages associated with Fe(III) and sulfate reduction (e.g. Desulfovibrionales; Syntrophobacterales; Peptococcaceae) and autotrophic sulfur oxidation (Sulfurovum; Campylobacterales). Data implies complex membership among highly stimulated taxa and, by inference, biogeochemical responses to acetate, a nonfermentable substrate. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  14. Behaviour and fate of nine recycled water trace organics during managed aquifer recharge in an aerobic aquifer

    Science.gov (United States)

    Patterson, B. M.; Shackleton, M.; Furness, A. J.; Bekele, E.; Pearce, J.; Linge, K. L.; Busetti, F.; Spadek, T.; Toze, S.

    2011-03-01

    The fate of nine trace organic compounds was evaluated during a 12 month large-scale laboratory column experiment. The columns were packed with aquifer sediment and evaluated under natural aerobic and artificial anaerobic geochemical conditions, to assess the potential for natural attenuation of these compounds during aquifer passage associated with managed aquifer recharge (MAR). The nine trace organic compounds were bisphenol A (BPA), 17β-estradiol (E2), 17α-ethynylestradiol (EE2), N-nitrosodimethylamine (NDMA), N-nitrosomorpholine (NMOR), carbamazepine, oxazepam, iohexol and iodipamide. In the low organic carbon content Spearwood sediment, all trace organics were non-retarded with retardation coefficients between 1.0 and 1.2, indicating that these compounds would travel at near groundwater velocities within the aquifer. The natural aerobic geochemical conditions provided a suitable environment for the rapid degradation for BPA, E2, iohexol (half life degradation of these compounds ranged from degradation (half life degrade under either aerobic or anaerobic aquifer geochemical conditions (half life > 50 days). Field-based validation experiments with carbamazepine and oxazepam also showed no degradation. If persistent trace organics are present in recycled waters at concentrations in excess of their intended use, natural attenuation during aquifer passage alone may not result in extracted water meeting regulatory requirements. Additional pre treatment of the recycled water would therefore be required.

  15. Uranium series geochemistry in aquifers: quantification of transport mechanisms of uranium and daughter products: the chalk aquifer (Champagne, France)

    International Nuclear Information System (INIS)

    Hubert, A.

    2005-09-01

    With the increase of contaminant flux of radionuclides in surface environment (soil, river, aquifer...), there is a need to understand and model the processes that control the distribution of uranium and its daughter products during transport within aquifers. We have used U-series disequilibria as an analogue for the transport of uranium and its daughter products in aquifer to understand such mechanisms. The measurements of uranium ( 234 U et 238 U), thorium ( 230 Th et 232 Th), 226 Ra and 222 Rn isotopes in the solid and liquid phases of the chalk aquifer in Champagne (East of France) allows us to understand the processes responsible for fractionation within the uranium decay chain. Fractionations are induced by physical and chemical properties of the elements (leaching, adsorption) but also by radioactive properties (recoil effect during α-decay). For the first time a comprehensive sampling of the solid phase has been performed, allowing quantifying mechanisms responsible for the long term evolution of the aquifer. A non steady state 1D model has been developed which takes into account leaching, adsorption processes as well as radioactive filiation and α-recoil effect. Retardation coefficients have been calculated for uranium, thorium and radium. The aquifer is characterised by a double porosity, and the contribution of fracture and matrix porosity on the water/rock interaction processes has been estimated. (author)

  16. Commercialization of aquifer thermal energy storage technology

    Energy Technology Data Exchange (ETDEWEB)

    Hattrup, M.P.; Weijo, R.O.

    1989-09-01

    Pacific Northwest Laboratory (PNL) conducted this study for the US Department of Energy's (DOE) Office of Energy Storage and Distribution. The purpose of the study was to develop and screen a list of potential entry market applications for aquifer thermal energy storage (ATES). Several initial screening criteria were used to identify promising ATES applications. These include the existence of an energy availability/usage mismatch, the existence of many similar applications or commercial sites, the ability to utilize proven technology, the type of location, market characteristics, the size of and access to capital investment, and the number of decision makers involved. The in-depth analysis identified several additional screening criteria to consider in the selection of an entry market application. This analysis revealed that the best initial applications for ATES are those where reliability is acceptable, and relatively high temperatures are allowable. Although chill storage was the primary focus of this study, applications that are good candidates for heat ATES were also of special interest. 11 refs., 3 tabs.

  17. The economics of aquifer storage recovery technology

    Energy Technology Data Exchange (ETDEWEB)

    David, R.; Pyne, G.

    2014-10-01

    Aquifer storage recovery (ASR) technology is increasingly being utilized around the world for storing water underground through one or more wells during wet months and other times when water is available for storage. The water is then recovered from the same wells when needed to meet a growing variety of water supply objectives. The economics of ASR constitute the principal reason for its increasing utilization. ASR unit capital costs are typically less than half those of other water supply and water storage alternatives. Unit operating costs are usually only slightly greater than for conventional production well-fields. Marginal costs for ASR storage and recovery provide a powerful tool for making more efficient use of existing infrastructure, providing water supply sustainability and reliability at relatively low cost. The opportunity exists for a careful analysis of the net present value of ASR well-fields, addressing not only the associated capital and operating costs but also the value of the benefits achieved for each of the water supply objectives at each site. (Author)

  18. Development of Managed Aquifer Recharge in China

    International Nuclear Information System (INIS)

    Wang, W.; Zhou, Y.; Sun, X.; Wang, W.

    2014-01-01

    China has a long history in managed aquifer recharge (MAR). The historic development can be divided into 4 stages based on a summary of typical MAR projects. The first stage is MAR applied to agricultural production, the second is MAR applied to industrial production and alleviation of agricultural problems, the third is MAR applied to ecological protection and the increase in urban water supplies, and the fourth is multi-source MAR. In addition, geothermal reinjection and ground source heat pumps are also effective uses of MAR. Nevertheless, the MAR framework is defective, there is a lack of water quality studies, and the recharge rate of most projects is low. However, China has achieved a great effect on industrial and agricultural production, ecological protection, drinking water supplies and urban reclaimed water reuse, amongst others. But there are still many issues to be improved. A feasible, convenient and economic technique of MAR which fits local hydrogeological conditions needs to be developed and guidelines for both MARs and management regulations to ensure the successful running of MAR projects also need to be established. MAR will make a great difference to improving potable water quality, alleviating geological hazards, long distance water diversion, urban water supplies, agriculture irrigation, etc. (Author)

  19. Soil aquifer treatment using advanced primary effluent

    KAUST Repository

    Sharma, Saroj K.

    2011-08-01

    Soil aquifer treatment (SAT) using primary effluent (PE) is an attractive option for wastewater treatment and reuse in many developing countries with no or minimal wastewater treatment. One of the main limitations of SAT of PE is rapid clogging of the infiltration basin due to high suspended solid concentrations. Some pre-treatment of PE before infiltration is likely to reduce this limitation, improve performance of SAT and help to implement this technology effectively. The effects of three pre-treatment options namely sedimentation (SED), coagulation (COAG) and horizontal roughing filtration (HRF) on SAT were analyzed by conducting laboratory-scale batch and soil column experiments. The sedimentation and coagulation pre-treatments led to less head loss development and reduction of clogging effect. The head loss development in soil column using PE + COAG and PE + SED was reduced by 85 and 72%, respectively, compared to PE alone without any pretreatment. The overall dissolved organic carbon (DOC) removal of pre-treatments and soil column collectively were 34, 44, 51 and 43.5% for PE without any pre-treatment, PE + SED, PE+ COAG and PE + HRF, respectively. Coagulation pre-treatment of PE was found to be the most effective option in terms of suspended solids, DOC and nitrogen removal. Sedimentation pre-treatment of PE could be attractive where land is relatively less expensive for the construction of sedimentation basins. © IWA Publishing 2011.

  20. Salmon Site Remedial Investigation Report, Appendix C

    International Nuclear Information System (INIS)

    1999-01-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the