Modeling foam delivery mechanisms in deep vadose-zone remediation using method of characteristics

Energy Technology Data Exchange (ETDEWEB)

Roostapour, A. [Craft and Hawkins Department of Petroleum Engineering, Louisiana State University, Baton Rouge, LA 70803 (United States); Kam, S.I., E-mail: kam@lsu.edu [Craft and Hawkins Department of Petroleum Engineering, Louisiana State University, Baton Rouge, LA 70803 (United States)

2012-12-15

Highlights: Black-Right-Pointing-Pointer A new mathematical framework established for vadose-zone foam remediation. Black-Right-Pointing-Pointer Graphical solutions presented by Method of Characteristics quantitatively. Black-Right-Pointing-Pointer Effects of design parameters in the field applications thoroughly investigated. Black-Right-Pointing-Pointer Implication of modeling study for successful field treatment discussed. - Abstract: This study investigates foam delivery mechanisms in vadose-zone remediation by using Method of Characteristics (MoC), a mathematical tool long been used for the analysis of miscible and immiscible flooding in porous media in petroleum industry. MoC converts the governing material-balance partial differential equations into a series of ordinary differential equations, and the resulting solutions are in a form of wave propagation (more specifically, for chemical species and phase saturations) through the system as a function of time and space. Deep vadose-zone remediation has special features compared to other conventional remediation applications. They include, not limited to, a high level of heterogeneity, a very dry initial condition with low water saturation (S{sub w}), pollutants such as metals and radionuclides fully dissolved in groundwater, and a serious concern about downward migration during the remediation treatments. For the vadose-zone remediation processes to be successful, the injected aqueous phase should carry chemicals to react with pollutants and precipitate them for immobilization and stabilization purposes. As a result, foams are believed to be an effective means, and understanding foam flow mechanism in situ is a key to the optimal design of field applications. Results show that foam delivery mechanism is indeed very complicated, making the optimum injection condition field-specific. The five major parameters selected (i.e., initial saturation of the medium, injection foam quality, surfactant adsorption, foam

Modeling foam delivery mechanisms in deep vadose-zone remediation using method of characteristics

International Nuclear Information System (INIS)

Roostapour, A.; Kam, S.I.

2012-01-01

Highlights: ► A new mathematical framework established for vadose-zone foam remediation. ► Graphical solutions presented by Method of Characteristics quantitatively. ► Effects of design parameters in the field applications thoroughly investigated. ► Implication of modeling study for successful field treatment discussed. - Abstract: This study investigates foam delivery mechanisms in vadose-zone remediation by using Method of Characteristics (MoC), a mathematical tool long been used for the analysis of miscible and immiscible flooding in porous media in petroleum industry. MoC converts the governing material-balance partial differential equations into a series of ordinary differential equations, and the resulting solutions are in a form of wave propagation (more specifically, for chemical species and phase saturations) through the system as a function of time and space. Deep vadose-zone remediation has special features compared to other conventional remediation applications. They include, not limited to, a high level of heterogeneity, a very dry initial condition with low water saturation (S w ), pollutants such as metals and radionuclides fully dissolved in groundwater, and a serious concern about downward migration during the remediation treatments. For the vadose-zone remediation processes to be successful, the injected aqueous phase should carry chemicals to react with pollutants and precipitate them for immobilization and stabilization purposes. As a result, foams are believed to be an effective means, and understanding foam flow mechanism in situ is a key to the optimal design of field applications. Results show that foam delivery mechanism is indeed very complicated, making the optimum injection condition field-specific. The five major parameters selected (i.e., initial saturation of the medium, injection foam quality, surfactant adsorption, foam strength, and foam stability) are shown to be all important, interacting with each other. Results also

Bioventing - a new twist on soil vapor remediation of the vadose zone and shallow ground water

International Nuclear Information System (INIS)

Yancheski, T.B.; McFarland, M.A.

1992-01-01

Bioventing, which is a combination of soil vapor remediation and bioremediation techniques, may be an innovative, cost-effective, and efficient remedial technology for addressing petroleum contamination in the vadose zone and shallow ground water. The objective of bioventing is to mobilize petroleum compounds from the soil and ground water into soil vapor using soil vapor extraction and injection technology, and to promote the migration of the soil vapor upward to the turf root zone for degradation by active near-surface microbiological activity. Promoting and maintaining optimum microbiological activity in the turf root rhizosphere is a key component to the bioventing technique. Preliminary ongoing USEPA bioventing pilot studies (Kampbell, 1991) have indicated that this technique is a promising remediation technology, although feasibility studies are not yet complete. However, based on the preliminary data, it appears that proper bioventing design and implementation will result in substantial reductions of petroleum compounds in the capillary zone and shallow ground water, complete degradation of petroleum compounds in the turf root zone, and no surface emissions. A bioventing system was installed at a site in southern Delaware with multiple leaking underground storage tanks in early 1992 to remediate vadose zone and shallow ground-water contaminated by petroleum compounds. The system consists of a series of soil vapor extraction and soil vapor/atmospheric air injection points placed in various contamination areas and a central core remediation area (a large grassy plot). This system was chosen for this site because it was least costly to implement and operate as compared to other remedial alternatives (soil vapor extraction with carbon or catalytic oxidation of off-gas treatment, insitu bioremediation, etc.), and results in the generation of no additional wastes

Critical Evaluation of State-of-the-Art In Situ Thermal Treatment Technologies for DNAPL Source Zone Treatment

Science.gov (United States)

2010-01-01

valent iron (ZVI) powder in a water/ guar slurry for remediation of chlorinated DNAPL source zones. The ZVI continues the remediation after the thermal...MUST BE FOLLOWED BY PERSONNEL ON SITE 1. Smoking, eating, chewing gum or tobacco, or drinking are forbidden except in clean or designated areas...WORK PRACTICES ER-0314 69 Appendix D THE FOLLOWING PRACTICES MUST BE FOLLOWED BY PERSONNEL ON SITE 12. Smoking, eating, chewing gum or tobacco

TREATABILITY TEST PLAN FOR DEEP VADOSE ZONE REMEDIATION AT THE HANFORD'S SITE CENTRAL PLATEAU

International Nuclear Information System (INIS)

PETERSEN SW; MORSE JG; TRUEX MJ; LAST GV

2007-01-01

A treatability test plan has been prepared to address options for remediating portions of the deep vadose zone beneath a portion of the U.S. Department of Energy's (DOE's) Hanford Site. The vadose zone is the region of the subsurface that extends from the ground surface to the water table. The overriding objective of the treatability test plan is to recommend specific remediation technologies and laboratory and field tests to support the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 and Resource Conservation and Recovery Act of 1976 remedial decision-making process in the Central Plateau of the Hanford Site. Most of the technologies considered involve removing water from the vadose zone or immobilizing the contaminants to reduce the risk of contaminating groundwater. A multi-element approach to initial treatability testing is recommended, with the goal of providing the information needed to evaluate candidate technologies. The proposed tests focus on mitigating two contaminants--uranium and technetium. Specific technologies are recommended for testing at areas that may affect groundwater in the future, but a strategy to test other technologies is also presented

Robust remediation strategies at gas-work sites: a case of source recognition and source characterization

International Nuclear Information System (INIS)

Vries, P.O. de

2005-01-01

In The Netherlands there have been gasworks at about 260 to 270 locations. Most of these locations are or were heavily polluted with tar, ashes and cyanides and many of them belong to the locations where remediation actions have already been executed. It seems however that many of them also belong to the locations where remediation actions were not quite as successful as was expected. So, for many gas-work sites that were already 'remedied' in the 80's and early 90's of the foregoing century, new programs for site remediation are planned. Of course the mistakes from the past should now be avoided. The current remediation strategy in The Netherlands for gas-work sites can be comprised in four steps: 1 - removing spots in the top soil, 2 - removing spots with mobile components in the shallow subsoil, 3 - controlling spots with mobile components in the deep subsoil, 4 - creating a 'steady endpoint situation' in the plume. At many former gas-work sites real sources, i.e. in a physico-chemical sense, are not very well known. This can easily lead to insufficient removal of some or part of these sources and cause a longer delivery of contaminants to the groundwater plume, with higher endpoint concentrations, higher costs and more restrictions for future use. The higher concentrations and longer deliveries originating from not recognized or not localized sources are often not sufficiently compensated by the proposed plume management in current remediation strategies. Remediation results can be improved by using knowledge about the processes that determine the delivery of contaminants to the groundwater, the materials that cause these delivery and the locations at the site where these are most likely found. When sources are present in the deep subsoil or the exact localization of sources is uncertain, robust remediation strategies should be chosen and wishful thinking about removing sources with in situ techniques should be avoided. Robust strategies are probably less

pH control for enhanced reductive bioremediation of chlorinated solvent source zones

International Nuclear Information System (INIS)

Robinson, Clare; Barry, D.A.; McCarty, Perry L.; Gerhard, Jason I.; Kouznetsova, Irina

2009-01-01

Enhanced reductive dehalogenation is an attractive treatment technology for in situ remediation of chlorinated solvent DNAPL source areas. Reductive dehalogenation is an acid-forming process with hydrochloric acid and also organic acids from fermentation of the electron donors typically building up in the source zone during remediation. This can lead to groundwater acidification thereby inhibiting the activity of dehalogenating microorganisms. Where the soils' natural buffering capacity is likely to be exceeded, the addition of an external source of alkalinity is needed to ensure sustained dehalogenation. To assist in the design of bioremediation systems, an abiotic geochemical model was developed to provide insight into the processes influencing the groundwater acidity as dehalogenation proceeds, and to predict the amount of bicarbonate required to maintain the pH at a suitable level for dehalogenating bacteria (i.e., > 6.5). The model accounts for the amount of chlorinated solvent degraded, site water chemistry, electron donor, alternative terminal electron-accepting processes, gas release and soil mineralogy. While calcite and iron oxides were shown to be the key minerals influencing the soil's buffering capacity, for the extensive dehalogenation likely to occur in a DNAPL source zone, significant bicarbonate addition may be necessary even in soils that are naturally well buffered. Results indicated that the bicarbonate requirement strongly depends on the electron donor used and availability of competing electron acceptors (e.g., sulfate, iron (III)). Based on understanding gained from this model, a simplified model was developed for calculating a preliminary design estimate of the bicarbonate addition required to control the pH for user-specified operating conditions.

Design requirements for ERD in diffusion-dominated media: how do injection interval, bioactive zones and reaction kinetics affect remediation performance?

Science.gov (United States)

Chambon, J.; Lemming, G.; Manoli, G.; Broholm, M. M.; Bjerg, P.; Binning, P. J.

2011-12-01

Enhanced Reductive Dechlorination (ERD) has been successfully used in high permeability media, such as sand aquifers, and is considered to be a promising technology for low permeability settings. Pilot and full-scale applications of ERD at several sites in Denmark have shown that the main challenge is to get contact between the injected bacteria and electron donor and the contaminants trapped in the low-permeability matrix. Sampling of intact cores from the low-permeability matrix has shown that the bioactive zones (where degradation occurs) are limited in the matrix, due to the slow diffusion transport processes, and this affects the timeframes for the remediation. Due to the limited ERD applications and the complex transport and reactive processes occurring in low-permeability media, design guidelines are currently not available for ERD in such settings, and remediation performance assessments are limited. The objective of this study is to combine existing knowledge from several sites with numerical modeling to assess the effect of the injection interval, development of bioactive zones and reaction kinetics on the remediation efficiency for ERD in diffusion-dominated media. A numerical model is developed to simulate ERD at a contaminated site, where the source area (mainly TCE) is located in a clayey till with fractures and interbedded sand lenses. Such contaminated sites are common in North America and Europe. Hydro-geological characterization provided information on geological heterogeneities and hydraulic parameters, which are relevant for clay till sites in general. The numerical model couples flow and transport in the fracture network and low-permeability matrix. Sequential degradation of TCE to ethene is modeled using Monod kinetics, and the kinetic parameters are obtained from laboratory experiments. The influence of the reaction kinetics on remediation efficiency is assessed by varying the biomass concentration of the specific degraders. The injected

A/M Area Vadose Zone Monitoring Plan (U)

International Nuclear Information System (INIS)

Kupar, J.; Jarosch, T.R.; Jackson, D.G. Jr.; Looney, B.B.; Jerome, K.M.; Riha, B.D.; Rossabi, J.; Van Pelt, R.S.

1998-03-01

Characterization and monitoring data from implementation and the first two and one half years of vadose zone remediation operations indicate that this activity has substantially improved the performance of the A/M Area Groundwater Corrective Action Program. During this period, vadose zone remediation removed approximately 225, 000 lbs (100,000 Kg) of chlorinated solvents (CVOCs) from the subsurface. Further, vadose zone remediation system operation increased the overall CVOC removal rate of the A/M Area Groundwater Corrective Action by 300% to 500% during this period versus the groundwater pump and treat system along. Various support activities have been performed to support operation and documentation of performance of the vadose zone remediation system. These activities address performance of existing systems (contaminant distributions, zone of influence, and process monitoring data), evaluation of suspect sources, evaluation of alternative/enhancement technologies, and initial development of remediation goals. In particular, the most recent A/M vadose zone remediation support activities (described in WSRC-RP-97-109) were completed and the results provide key documentation about system performance

Environmental impact of ongoing sources of metal contamination on remediated sediments

Energy Technology Data Exchange (ETDEWEB)

Knox, Anna Sophia, E-mail: anna.knox@srn.doe.gov [Savannah River National Laboratory, Aiken, SC 29808 (United States); Paller, Michael H., E-mail: michael.paller@srnl.doe.gov [Savannah River National Laboratory, Aiken, SC 29808 (United States); Milliken, Charles E., E-mail: charles.milliken@srnl.doe.gov [Savannah River National Laboratory, Aiken, SC 29808 (United States); Redder, Todd M., E-mail: tredder@limno.com [LimnoTech, Ann Arbor, Minnesota 48108 (United States); Wolfe, John R., E-mail: jwolfe@limno.com [LimnoTech, Ann Arbor, Minnesota 48108 (United States); Seaman, John, E-mail: seaman@srel.uga.edu [Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802 (United States)

2016-09-01

A challenge to all remedial approaches for contaminated sediments is the continued influx of contaminants from uncontrolled sources following remediation. We investigated the effects of ongoing contamination in mesocosms employing sediments remediated by different types of active and passive caps and in-situ treatment. Our hypothesis was that the sequestering agents used in active caps and in situ treatment will bind elements (arsenic, chromium, cadmium, cobalt, copper, nickel, lead, selenium, and zinc) from ongoing sources thereby reducing their bioavailability and protecting underlying remediated sediments from recontamination. Most element concentrations in surface water remained significantly lower in mesocosms with apatite and mixed amendment caps than in mesocosms with passive caps (sand), uncapped sediment, and spike solution throughout the 2520 h experiment. Element concentrations were significantly higher in Lumbriculus variegatus from untreated sediment than in Lumbriculus from most active caps. Pearson correlations between element concentrations in Lumbriculus and metal concentrations in the top 2.5 cm of sediment or cap measured by diffusive gradient in thin films (DGT) sediment probes were generally strong (as high as 0.98) and significant (p < 0.05) for almost all tested elements. Metal concentrations in both Lumbriculus and sediment/cap were lowest in apatite, mixed amendment, and activated carbon treatments. These findings show that some active caps can protect remediated sediments by reducing the bioavailable pool of metals/metalloids in ongoing sources of contamination. - Graphical abstract: Conventional methods of remediating contaminated sediments may be inadequate for the protection of benthic organisms when ongoing sources of contamination are present. However, sediment caps with chemically active sequestering agents have the ability to reduce the bioavailable pool of metals in ongoing sources of contamination (red dots), reduce toxicity to

Environmental impact of ongoing sources of metal contamination on remediated sediments

International Nuclear Information System (INIS)

Knox, Anna Sophia; Paller, Michael H.; Milliken, Charles E.; Redder, Todd M.; Wolfe, John R.; Seaman, John

2016-01-01

A challenge to all remedial approaches for contaminated sediments is the continued influx of contaminants from uncontrolled sources following remediation. We investigated the effects of ongoing contamination in mesocosms employing sediments remediated by different types of active and passive caps and in-situ treatment. Our hypothesis was that the sequestering agents used in active caps and in situ treatment will bind elements (arsenic, chromium, cadmium, cobalt, copper, nickel, lead, selenium, and zinc) from ongoing sources thereby reducing their bioavailability and protecting underlying remediated sediments from recontamination. Most element concentrations in surface water remained significantly lower in mesocosms with apatite and mixed amendment caps than in mesocosms with passive caps (sand), uncapped sediment, and spike solution throughout the 2520 h experiment. Element concentrations were significantly higher in Lumbriculus variegatus from untreated sediment than in Lumbriculus from most active caps. Pearson correlations between element concentrations in Lumbriculus and metal concentrations in the top 2.5 cm of sediment or cap measured by diffusive gradient in thin films (DGT) sediment probes were generally strong (as high as 0.98) and significant (p < 0.05) for almost all tested elements. Metal concentrations in both Lumbriculus and sediment/cap were lowest in apatite, mixed amendment, and activated carbon treatments. These findings show that some active caps can protect remediated sediments by reducing the bioavailable pool of metals/metalloids in ongoing sources of contamination. - Graphical abstract: Conventional methods of remediating contaminated sediments may be inadequate for the protection of benthic organisms when ongoing sources of contamination are present. However, sediment caps with chemically active sequestering agents have the ability to reduce the bioavailable pool of metals in ongoing sources of contamination (red dots), reduce toxicity to

Challenges in subsurface in situ remediation of chlorinated solvents

DEFF Research Database (Denmark)

Broholm, Mette Martina; Fjordbøge, Annika Sidelmann; Christiansen, Camilla Maymann

2014-01-01

Chlorinated solvent source zones in the subsurface pose a continuous threat to groundwater quality at many sites worldwide. In situ remediation of these sites is particularly challenging in heterogeneous fractured media and where the solvents are present as DNAPL. In situ remediation by chemical...

pH control for enhanced reductive bioremediation of chlorinated solvent source zones

Energy Technology Data Exchange (ETDEWEB)

Robinson, Clare, E-mail: clare.robinson@epfl.ch [Laboratoire de technologie ecologique, Institut d' ingenierie de l' environnement, Station No. 2, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland); Now at: Department of Civil and Environmental Engineering, University of Western Ontario, London, Canada N6A 5B9 (Canada); Barry, D.A., E-mail: andrew.barry@epfl.ch [Laboratoire de technologie ecologique, Institut d' ingenierie de l' environnement, Station No. 2, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland); McCarty, Perry L., E-mail: pmccarty@stanford.edu [Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305-4020 (United States); Gerhard, Jason I., E-mail: j.gerhard@ed.ac.uk [Now at: Department of Civil and Environmental Engineering, University of Western Ontario, London, Canada N6A 5B9 (Canada); Institute for Infrastructure and Environment, University of Edinburgh, Edinburgh, EH9 3JL (United Kingdom); Kouznetsova, Irina, E-mail: irina.kouznetsova@ed.ac.uk [Institute for Infrastructure and Environment, University of Edinburgh, Edinburgh, EH9 3JL (United Kingdom)

2009-08-01

Enhanced reductive dehalogenation is an attractive treatment technology for in situ remediation of chlorinated solvent DNAPL source areas. Reductive dehalogenation is an acid-forming process with hydrochloric acid and also organic acids from fermentation of the electron donors typically building up in the source zone during remediation. This can lead to groundwater acidification thereby inhibiting the activity of dehalogenating microorganisms. Where the soils' natural buffering capacity is likely to be exceeded, the addition of an external source of alkalinity is needed to ensure sustained dehalogenation. To assist in the design of bioremediation systems, an abiotic geochemical model was developed to provide insight into the processes influencing the groundwater acidity as dehalogenation proceeds, and to predict the amount of bicarbonate required to maintain the pH at a suitable level for dehalogenating bacteria (i.e., > 6.5). The model accounts for the amount of chlorinated solvent degraded, site water chemistry, electron donor, alternative terminal electron-accepting processes, gas release and soil mineralogy. While calcite and iron oxides were shown to be the key minerals influencing the soil's buffering capacity, for the extensive dehalogenation likely to occur in a DNAPL source zone, significant bicarbonate addition may be necessary even in soils that are naturally well buffered. Results indicated that the bicarbonate requirement strongly depends on the electron donor used and availability of competing electron acceptors (e.g., sulfate, iron (III)). Based on understanding gained from this model, a simplified model was developed for calculating a preliminary design estimate of the bicarbonate addition required to control the pH for user-specified operating conditions.

ZVI-Clay remediation of a chlorinated solvent source zone, Skuldelev, Denmark: 2. Groundwater contaminant mass discharge reduction

DEFF Research Database (Denmark)

Fjordbøge, Annika Sidelmann; Lange, Ida Vedel; Bjerg, Poul Løgstrup

2012-01-01

The impact of source mass depletion on the down-gradient contaminant mass discharge was monitored for a 19-month period as a part of a field demonstration of the ZVI-Clay soil mixing remediation technology. Groundwater samples were collected from conventional monitoring wells (120 samples) and a ...... down-gradient contaminant mass discharge reduction (76%) for the parent compound (PCE), while the overall reduction of chlorinated ethenes was smaller (21%)....

The role of remediation, natural alkalinity sources and physical stream parameters in stream recovery.

Science.gov (United States)

Kruse, Natalie A; DeRose, Lisa; Korenowsky, Rebekah; Bowman, Jennifer R; Lopez, Dina; Johnson, Kelly; Rankin, Edward

2013-10-15

Acid mine drainage (AMD) negatively impacts not only stream chemistry, but also aquatic biology. The ultimate goal of AMD treatment is restoration of the biological community, but that goal is rarely explicit in treatment system design. Hewett Fork in Raccoon Creek Watershed, Ohio, has been impacted by historic coal mining and has been treated with a calcium oxide doser in the headwaters of the watershed since 2004. All of the acidic inputs are isolated to a 1.5 km stretch of stream in the headwaters of the Hewett Fork watershed. The macroinvertebrate and fish communities have begun to recover and it is possible to distinguish three zones downstream of the doser: an impaired zone, a transition zone and a recovered zone. Alkalinity from both the doser and natural sources and physical stream parameters play a role in stream restoration. In Hewett Fork, natural alkaline additions downstream are higher than those from the doser. Both, alkaline additions and stream velocity drive sediment and metal deposition. Metal deposition occurs in several patterns; aluminum tends to deposit in regions of low stream velocity, while iron tends to deposit once sufficient alkalinity is added to the system downstream of mining inputs. The majority of metal deposition occurs upstream of the recovered zone. Both the physical stream parameters and natural alkalinity sources influence biological recovery in treated AMD streams and should be considered in remediation plans. Copyright © 2013 Elsevier Ltd. All rights reserved.

Experimental and Numerical Investigations of Soil Desiccation for Vadose Zone Remediation: Report for Fiscal Year 2007

Energy Technology Data Exchange (ETDEWEB)

Ward, Andy L.; Oostrom, Mart; Bacon, Diana H.

2008-02-04

Apart from source excavation, the options available for the remediation of vadose zone metal and radionuclide contaminants beyond the practical excavation depth (0 to 15 m) are quite limited. Of the available technologies, very few are applicable to the deep vadose zone with the top-ranked candidate being soil desiccation. An expert panel review of the work on infiltration control and supplemental technologies identified a number of knowledge gaps that would need to be overcome before soil desiccation could be deployed. The report documents some of the research conducted in the last year to fill these knowledge gaps. This work included 1) performing intermediate-scale laboratory flow cell experiments to demonstrate the desiccation process, 2) implementing a scalable version of Subsurface Transport Over Multiple Phases–Water-Air-Energy (STOMP-WAE), and 3) performing numerical experiments to identify the factors controlling the performance of a desiccation system.

Hydrogeophysical imaging of deposit heterogeneity and groundwater chemistry changes during DNAPL source zone bioremediation.

Science.gov (United States)

Chambers, J E; Wilkinson, P B; Wealthall, G P; Loke, M H; Dearden, R; Wilson, R; Allen, D; Ogilvy, R D

2010-10-21

Robust characterization and monitoring of dense nonaqueous phase liquid (DNAPL) source zones is essential for designing effective remediation strategies, and for assessing the efficacy of treatment. In this study high-resolution cross-hole electrical resistivity tomography (ERT) was evaluated as a means of monitoring a field-scale in-situ bioremediation experiment, in which emulsified vegetable oil (EVO) electron donor was injected into a trichloroethene source zone. Baseline ERT scans delineated the geometry of the interface between the contaminated alluvial aquifer and the underlying mudstone bedrock, and also the extent of drilling-induced physical heterogeneity. Time-lapse ERT images revealed major preferential flow pathways in the source and plume zones, which were corroborated by multiple lines of evidence, including geochemical monitoring and hydraulic testing using high density multilevel sampler arrays within the geophysical imaging planes. These pathways were shown to control the spatial distribution of the injected EVO, and a bicarbonate buffer introduced into the cell for pH control. Resistivity signatures were observed within the preferential flow pathways that were consistent with elevated chloride levels, providing tentative evidence from ERT of the biodegradation of chlorinated solvents. Copyright © 2010 S. Yamamoto. Published by Elsevier B.V. All rights reserved.

ZVI-Clay remediation of a chlorinated solvent source zone, Skuldelev, Denmark: 1. Site description and contaminant source mass reduction

DEFF Research Database (Denmark)

Fjordbøge, Annika Sidelmann; Riis, Charlotte; Christensen, Anders G.

2012-01-01

Field investigations on the effects of ZVI-Clay soil mixing were conducted at a small DNAPL source zone with PCE as the parent compound. In a one-year monitoring program, soil samples were collected at three horizontal sampling planes (2.5, 5.0 and 7.5m bgs.). PCE was found to have a pseudo first...

Mass Transfer Limited Enhanced Bioremediation at Dnapl Source Zones: a Numerical Study

Science.gov (United States)

Kokkinaki, A.; Sleep, B. E.

2011-12-01

The success of enhanced bioremediation of dense non-aqueous phase liquids (DNAPLs) relies on accelerating contaminant mass transfer from the organic to the aqueous phase, thus enhancing the depletion of DNAPL source zones compared to natural dissolution. This is achieved by promoting biological activity that reduces the contaminant's aqueous phase concentration. Although laboratory studies have demonstrated that high reaction rates are attainable by specialized microbial cultures in DNAPL source zones, field applications of the technology report lower reaction rates and prolonged remediation times. One possible explanation for this phenomenon is that the reaction rates are limited by the rate at which the contaminant partitions from the DNAPL to the aqueous phase. In such cases, slow mass transfer to the aqueous phase reduces the bioavailability of the contaminant and consequently decreases the potential source zone depletion enhancement. In this work, the effect of rate limited mass transfer on bio-enhanced dissolution of DNAPL chlorinated ethenes is investigated through a numerical study. A multi-phase, multi-component groundwater transport model is employed to simulate DNAPL mass depletion for a range of source zone scenarios. Rate limited mass transfer is modeled by a linear driving force model, employing a thermodynamic approach for the calculation of the DNAPL - water interfacial area. Metabolic reductive dechlorination is modeled by Monod kinetics, considering microbial growth and self-inhibition. The model was utilized to identify conditions in which mass transfer, rather than reaction, is the limiting process, as indicated by the bioavailability number. In such cases, reaction is slower than expected, and further increase in the reaction rate does not enhance mass depletion. Mass transfer rate limitations were shown to affect both dechlorination and microbial growth kinetics. The complex dynamics between mass transfer, DNAPL transport and distribution, and

DNAPL Surface Chemistry: Its Impact on DNAPL Distribution in the Vadose Zone and its Manipulation to Enhance Remediation

Energy Technology Data Exchange (ETDEWEB)

Suan Power; Stefan Grimberg; Miles Denham

2003-06-16

The remediation of DNAPLs in subsurface environments is often limited by the heterogeneous distribution of the organic fluid. The fraction of DNAPL that is in the high conductivity regions of the subsurface can often be recovered relatively easily, although DNAPL in lower conductivity regions is much more difficult to extract, either through direct pumping or remediation measures based on interface mass transfer. The distribution of DNAPL within the vadose zone is affected by a complex interplay of heterogeneities in the porous matrix and the interfacial properties defining the interactions among all fluid and solid phases. Decreasing the interfacial tension between a DNAPL and water in the vadose zone could change the spreading of the DNAPL, thereby increase the surface area for mass transfer and the effectiveness of soil vapor extraction remediation.

Selection of monitoring times to assess remediation performance

Energy Technology Data Exchange (ETDEWEB)

Kueper, B.H.; Mundle, K. [Queen' s Univ., Kingston, ON (Canada). Dept. of Civil Engineering, Geoengineering Centre

2007-07-01

Several factors determine the time needed for a plume to respond to non-aqueous phase liquid (NAPL) source zone remediation. Most spills of NAPLs (fuels, chlorinated solvents, PCB oils, creosote and coal tar) require mass removal in order to implement remediation technologies such as chemical oxidation, thermal treatments, alcohol flushing, surfactant flushing and hydraulic displacement. While much attention has been given to the development of these remediation technologies, little attention has been given to the response of the plume downstream of the treatment zone and selection of an appropriate monitoring time scale to adequately evaluate the impacts of remediation. For that reason, this study focused on the prevalence of diffusive sinks, the mobility of the contaminant and the hydraulic conductivity of subsurface materials. Typically, plumes in subsurface environments dominated by diffusive sinks or low permeability materials need long periods of time to detach after source removal. This paper presented generic plume response model simulations that illustrated concentration rebound following the use of in-situ chemical oxidation in fractured clay containing trichloroethylene. It was determined that approximately 2 years are needed to reach peak rebound concentration after cessation remedial action. It was concluded that downgradient monitoring well concentrations may be greatly reduced during remedial action due to the fact that oxidant occupies the fracture and because oxidant diffuses into the clay matrix, creating a short period of contaminant reduction in the area of flowing groundwater. 9 refs., 2 tabs., 7 figs.

Selection of monitoring times to assess remediation performance

International Nuclear Information System (INIS)

Kueper, B.H.; Mundle, K.

2007-01-01

Several factors determine the time needed for a plume to respond to non-aqueous phase liquid (NAPL) source zone remediation. Most spills of NAPLs (fuels, chlorinated solvents, PCB oils, creosote and coal tar) require mass removal in order to implement remediation technologies such as chemical oxidation, thermal treatments, alcohol flushing, surfactant flushing and hydraulic displacement. While much attention has been given to the development of these remediation technologies, little attention has been given to the response of the plume downstream of the treatment zone and selection of an appropriate monitoring time scale to adequately evaluate the impacts of remediation. For that reason, this study focused on the prevalence of diffusive sinks, the mobility of the contaminant and the hydraulic conductivity of subsurface materials. Typically, plumes in subsurface environments dominated by diffusive sinks or low permeability materials need long periods of time to detach after source removal. This paper presented generic plume response model simulations that illustrated concentration rebound following the use of in-situ chemical oxidation in fractured clay containing trichloroethylene. It was determined that approximately 2 years are needed to reach peak rebound concentration after cessation remedial action. It was concluded that downgradient monitoring well concentrations may be greatly reduced during remedial action due to the fact that oxidant occupies the fracture and because oxidant diffuses into the clay matrix, creating a short period of contaminant reduction in the area of flowing groundwater. 9 refs., 2 tabs., 7 figs

Field demonstration of foam injection to confine a chlorinated solvent source zone.

Science.gov (United States)

Portois, Clément; Essouayed, Elyess; Annable, Michael D; Guiserix, Nathalie; Joubert, Antoine; Atteia, Olivier

2018-05-01

A novel approach using foam to manage hazardous waste was successfully demonstrated under active site conditions. The purpose of the foam was to divert groundwater flow, that would normally enter the source zone area, to reduce dissolved contaminant release to the aquifer. During the demonstration, foam was pre generated and directly injected surrounding the chlorinated solvent source zone. Despite the constraints related to the industrial activities and non-optimal position of the injection points, the applicability and effectiveness of the approach have been highlighted using multiple metrics. A combination of measurements and modelling allowed definition of the foam extent surrounding each injection point, and this appears to be the critical metric to define the success of the foam injection approach. Information on the transport of chlorinated solvents in groundwater showed a decrease of contaminant flux by a factor of 4.4 downstream of the confined area. The effective permeability reduction was maintained over a period of three months. The successful containment provides evidence for consideration of the use of foam to improve traditional flushing techniques, by increasing the targeting of contaminants by remedial agents. Copyright © 2018 Elsevier B.V. All rights reserved.

Field-scale forward and back diffusion through low-permeability zones

Science.gov (United States)

Yang, Minjune; Annable, Michael D.; Jawitz, James W.

2017-07-01

Understanding the effects of back diffusion of groundwater contaminants from low-permeability zones to aquifers is critical to making site management decisions related to remedial actions. Here, we combine aquifer and aquitard data to develop recommended site characterization strategies using a three-stage classification of plume life cycle based on the solute origins: aquifer source zone dissolution, source zone dissolution combined with back diffusion from an aquitard, and only back diffusion. We use measured aquitard concentration profile data from three field sites to identify signature shapes that are characteristic of these three stages. We find good fits to the measured data with analytical solutions that include the effects of advection and forward and back diffusion through low-permeability zones, and linearly and exponentially decreasing flux resulting from source dissolution in the aquifer. Aquifer contaminant time series data at monitoring wells from a mature site were well described using analytical solutions representing the combined case of source zone and back diffusion, while data from a site where the source had been isolated were well described solely by back diffusion. The modeling approach presented in this study is designed to enable site managers to implement appropriate remediation technologies at a proper timing for high- and low-permeability zones, considering estimated plume life cycle.

Sources and remediation for mercury contamination in aquatic systems--a literature review

International Nuclear Information System (INIS)

Wang, Qianrui; Kim, Daekeun; Dionysiou, Dionysios D.; Sorial, George A.; Timberlake, Dennis

2004-01-01

Sources of mercury contamination in aquatic systems were studied in a comprehensive literature review. The results show that the most important anthropogenic sources of mercury pollution in aquatic systems are: (1) atmospheric deposition, (2) erosion, (3) urban discharges, (4) agricultural materials, (5) mining, and (6) combustion and industrial discharges. Capping and dredging are two possible remedial approaches to mercury contamination in aquatic systems, and natural attenuation is a passive decontamination alternative. Capping seems to be an economical and effective remedial approach to mercury-contaminated aquatic systems. Dredging is an expensive remedial approach. However, for heavily polluted systems, dredging may be more effective. Natural attenuation, involving little or no cost, is a possible and very economical choice for less contaminated sites. Proper risk assessment is necessary to evaluate the effectiveness of remedial and passive decontamination methods as well as their potential adverse environmental effects. Modeling tools have a bright future in the remediation and passive decontamination of mercury contamination in aquatic systems. Existing mercury transport and transformation models were reviewed and compared

Design requirements for ERD in diffusion-dominated media: how do injection interval, bioactive zones and reaction kinetics affect remediation performance?

DEFF Research Database (Denmark)

Chambon, Julie Claire Claudia; Lemming, Gitte; Manoli, Gabriele

is to get contact between the injected bacteria and electron donor and the contaminants trapped in the low-permeability matrix. Sampling of intact cores from the low-permeability matrix has shown that the bioactive zones (where degradation occurs) are limited in the matrix, due to the slow diffusion...... is developed to simulate ERD at a contaminated site, where the source area (mainly TCE) is located in a clayey till with fractures and interbedded sand lenses. Such contaminated sites are common in North America and Europe. Hydro-geological characterization provided information on geological heterogeneities...... experiments. The influence of the reaction kinetics on remediation efficiency is assessed by varying the biomass concentration of the specific degraders. The injected reactants (donor and bacteria) are assumed to spread in horizontal injection zones of various widths, depending on the development of bioactive...

A statistical approach to evaluate hydrocarbon remediation in the unsaturated zone

International Nuclear Information System (INIS)

Hajali, P.; Marshall, T.; Overman, S.

1991-01-01

This paper presents an evaluation of performance and cleanup effectiveness of a vapor extraction system (VES) in extracting chlorinated hydrocarbons and petroleum-based hydrocarbons (mineral spirits) from the unsaturated zone. The statistical analysis of soil concentration data to evaluate the VES remediation success is described. The site is a former electronics refurbishing facility in southern California; soil contamination from organic solvents was found mainly in five areas (Area A through E) beneath two buildings. The evaluation begins with a brief description of the site background, discusses the statistical approach, and presents conclusions

Characterization of DNAPL Source Zone Architecture and Prediction of Associated Plume Response: Progress and Perspectives

Science.gov (United States)

Abriola, L. M.; Pennell, K. D.; Ramsburg, C. A.; Miller, E. L.; Christ, J.; Capiro, N. L.; Mendoza-Sanchez, I.; Boroumand, A.; Ervin, R. E.; Walker, D. I.; Zhang, H.

2012-12-01

It is now widely recognized that the distribution of contaminant mass will control both the evolution of aqueous phase plumes and the effectiveness of many source zone remediation technologies at sites contaminated by dense nonaqueous phase liquids (DNAPLs). Advances in the management of sites containing DNAPL source zones, however, are currently hampered by the difficulty associated with characterizing subsurface DNAPL 'architecture'. This presentation provides an overview of recent research, integrating experimental and mathematical modeling studies, designed to improve our ability to characterize DNAPL distributions and predict associated plume response. Here emphasis is placed on estimation of the most information-rich DNAPL architecture metrics, through a combination of localized in situ tests and more readily available plume transect concentration observations. Estimated metrics will then serve as inputs to an upscaled screening model for prediction of long term plume response. Machine learning techniques were developed and refined to identify a variety of source zone metrics and associated confidence intervals through the processing of down gradient concentration data. Estimated metrics include the volumes and volume percentages of DNAPL in pools and ganglia, as well as their ratio (pool fraction). Multiphase flow and transport simulations provided training data for model development and assessment that are representative of field-scale DNAPL source zones and their evolving plumes. Here, a variety of release and site heterogeneity (sequential Gaussian permeability) conditions were investigated. Push-pull tracer tests were also explored as a means to provide localized in situ observations to refine these metric estimates. Here, two-dimensional aquifer cell experiments and mathematical modeling were used to quantify upscaled interphase mass transfer rates and the interplay between injection and extraction rates, local source zone architecture, and tracer

Using the natural biodegradation potential of shallow soils for in-situ remediation of deep vadose zone and groundwater

Energy Technology Data Exchange (ETDEWEB)

Avishai, Lior; Siebner, Hagar; Dahan, Ofer, E-mail: odahan@bgu.ac.il; Ronen, Zeev, E-mail: zeevrone@bgu.ac.il

2017-02-15

Highlights: • Integrated in-situ remediation treatment for soil, vadose zone and groundwater. • Turning the topsoil into an efficient bioreactor for perchlorate degradation. • Treating perchlorate leachate from the deep vadose zone in the topsoil. • Zero effluents discharge from the remediation process. - Abstract: In this study, we examined the ability of top soil to degrade perchlorate from infiltrating polluted groundwater under unsaturated conditions. Column experiments designed to simulate typical remediation operation of daily wetting and draining cycles of contaminated water amended with an electron donor. Covering the infiltration area with bentonite ensured anaerobic conditions. The soil remained unsaturated, and redox potential dropped to less than −200 mV. Perchlorate was reduced continuously from ∼1150 mg/L at the inlet to ∼300 mg/L at the outlet in daily cycles. Removal efficiency was between 60 and 84%. No signs of bioclogging were observed during three operation months although occasional iron reduction observed due to excess electron donor. Changes in perchlorate reducing bacteria numbers were inferred from an increased in pcrA gene abundances from ∼10{sup 5} to 10{sup 7} copied per gram at the end of the experiment indicating the growth of perchlorate-reducing bacteria. We proposed that the topsoil may serve as a bioreactor to treat high concentrations of perchlorate from the contaminated groundwater. The treated water that infiltrates from the topsoil through the vadose zone could be used to flush perchlorate from the deep vadose zone into the groundwater where it is retrieved again for treatment in the topsoil.

Using the natural biodegradation potential of shallow soils for in-situ remediation of deep vadose zone and groundwater

International Nuclear Information System (INIS)

Avishai, Lior; Siebner, Hagar; Dahan, Ofer; Ronen, Zeev

2017-01-01

Highlights: • Integrated in-situ remediation treatment for soil, vadose zone and groundwater. • Turning the topsoil into an efficient bioreactor for perchlorate degradation. • Treating perchlorate leachate from the deep vadose zone in the topsoil. • Zero effluents discharge from the remediation process. - Abstract: In this study, we examined the ability of top soil to degrade perchlorate from infiltrating polluted groundwater under unsaturated conditions. Column experiments designed to simulate typical remediation operation of daily wetting and draining cycles of contaminated water amended with an electron donor. Covering the infiltration area with bentonite ensured anaerobic conditions. The soil remained unsaturated, and redox potential dropped to less than −200 mV. Perchlorate was reduced continuously from ∼1150 mg/L at the inlet to ∼300 mg/L at the outlet in daily cycles. Removal efficiency was between 60 and 84%. No signs of bioclogging were observed during three operation months although occasional iron reduction observed due to excess electron donor. Changes in perchlorate reducing bacteria numbers were inferred from an increased in pcrA gene abundances from ∼10"5 to 10"7 copied per gram at the end of the experiment indicating the growth of perchlorate-reducing bacteria. We proposed that the topsoil may serve as a bioreactor to treat high concentrations of perchlorate from the contaminated groundwater. The treated water that infiltrates from the topsoil through the vadose zone could be used to flush perchlorate from the deep vadose zone into the groundwater where it is retrieved again for treatment in the topsoil.

Monitoring well utility in a heterogeneous DNAPL source zone area: Insights from proximal multilevel sampler wells and sampling capture-zone modelling.

Science.gov (United States)

McMillan, Lindsay A; Rivett, Michael O; Wealthall, Gary P; Zeeb, Peter; Dumble, Peter

2018-03-01

Groundwater-quality assessment at contaminated sites often involves the use of short-screen (1.5 to 3 m) monitoring wells. However, even over these intervals considerable variation may occur in contaminant concentrations in groundwater adjacent to the well screen. This is especially true in heterogeneous dense non-aqueous phase liquid (DNAPL) source zones, where cm-scale contamination variability may call into question the effectiveness of monitoring wells to deliver representative data. The utility of monitoring wells in such settings is evaluated by reference to high-resolution multilevel sampler (MLS) wells located proximally to short-screen wells, together with sampling capture-zone modelling to explore controls upon well sample provenance and sensitivity to monitoring protocols. Field data are analysed from the highly instrumented SABRE research site that contained an old trichloroethene source zone within a shallow alluvial aquifer at a UK industrial facility. With increased purging, monitoring-well samples tend to a flow-weighted average concentration but may exhibit sensitivity to the implemented protocol and degree of purging. Formation heterogeneity adjacent to the well-screen particularly, alongside pump-intake position and water level, influence this sensitivity. Purging of low volumes is vulnerable to poor reproducibility arising from concentration variability predicted over the initial 1 to 2 screen volumes purged. Marked heterogeneity may also result in limited long-term sample concentration stabilization. Development of bespoke monitoring protocols, that consider screen volumes purged, alongside water-quality indicator parameter stabilization, is recommended to validate and reduce uncertainty when interpreting monitoring-well data within source zone areas. Generalised recommendations on monitoring well based protocols are also developed. A key monitoring well utility is their proportionately greater sample draw from permeable horizons constituting

Monitoring well utility in a heterogeneous DNAPL source zone area: Insights from proximal multilevel sampler wells and sampling capture-zone modelling

Science.gov (United States)

McMillan, Lindsay A.; Rivett, Michael O.; Wealthall, Gary P.; Zeeb, Peter; Dumble, Peter

2018-03-01

Groundwater-quality assessment at contaminated sites often involves the use of short-screen (1.5 to 3 m) monitoring wells. However, even over these intervals considerable variation may occur in contaminant concentrations in groundwater adjacent to the well screen. This is especially true in heterogeneous dense non-aqueous phase liquid (DNAPL) source zones, where cm-scale contamination variability may call into question the effectiveness of monitoring wells to deliver representative data. The utility of monitoring wells in such settings is evaluated by reference to high-resolution multilevel sampler (MLS) wells located proximally to short-screen wells, together with sampling capture-zone modelling to explore controls upon well sample provenance and sensitivity to monitoring protocols. Field data are analysed from the highly instrumented SABRE research site that contained an old trichloroethene source zone within a shallow alluvial aquifer at a UK industrial facility. With increased purging, monitoring-well samples tend to a flow-weighted average concentration but may exhibit sensitivity to the implemented protocol and degree of purging. Formation heterogeneity adjacent to the well-screen particularly, alongside pump-intake position and water level, influence this sensitivity. Purging of low volumes is vulnerable to poor reproducibility arising from concentration variability predicted over the initial 1 to 2 screen volumes purged. Marked heterogeneity may also result in limited long-term sample concentration stabilization. Development of bespoke monitoring protocols, that consider screen volumes purged, alongside water-quality indicator parameter stabilization, is recommended to validate and reduce uncertainty when interpreting monitoring-well data within source zone areas. Generalised recommendations on monitoring well based protocols are also developed. A key monitoring well utility is their proportionately greater sample draw from permeable horizons constituting a

Natural Remediation at Savannah River Site

International Nuclear Information System (INIS)

Lewis, C. M.; Van Pelt, R.

2002-01-01

Natural remediation is a general term that includes any technology or strategy that takes advantage of natural processes to remediate a contaminated media to a condition that is protective of human health and the environment. Natural remediation techniques are often passive and minimally disruptive to the environment. They are generally implemented in conjunction with traditional remedial solutions for source control (i.e., capping, stabilization, removal, soil vapor extraction, etc.). Natural remediation techniques being employed at Savannah River Site (SRS) include enhanced bio-remediation, monitored natural attenuation, and phytoremediation. Enhanced bio-remediation involves making nutrients available and conditions favorable for microbial growth. With proper precautions and feeding, the naturally existing microbes flourish and consume the contaminants. Case studies of enhanced bio-remediation include surface soils contaminated with PCBs and pesticides, and Volatile Organic Compound (VOC) contamination in both the vadose zone and groundwater. Monitored natural attenuation (MNA) has been selected as the preferred alternative for groundwater clean up at several SRS waste units. Successful implementation of MNA has been based on demonstration that sources have been controlled, groundwater modeling that indicates that plumes will not expand or reach surface water discharge points at levels that exceed regulatory limits, and continued monitoring. Phytoremediation is being successfully utilized at several SRS waste units. Phytoremediation involves using plants and vegetation to uptake, break down, or manage contaminants in groundwater or soils. Case studies at SRS include managing groundwater plumes of tritium and VOCs with pine trees that are native to the area. Significant decreases in tritium discharge to a site stream have been realized in one phytoremediation project. Studies of other vegetation types, methods of application, and other target contaminants are

In situ vadose zone remediation of petroleum-contaminated soils

International Nuclear Information System (INIS)

Greacen, J.R.; Finkel, D.J.

1991-01-01

This paper discusses a pilot-scale system treating vadose zone soils contaminated with petroleum products constructed and operated at a former petroleum bulk storage terminal in New England. A site investigation following decommissioning activities identified more than 100,000 yds of soil at the site contaminated by both No. 2 fuel oil and gasoline. Soil cleanup criteria of 50 ppm TPH and 0.25 ppm BTEX were established. A pilot-scale treatment unit with dimensions of 125 ft x 125 ft x 6 ft was constructed to evaluate the potential for in situ treatment of vadose zone soils. Contaminant levels in pilot cell soils ranged from 0 to 5,250 ppm TPH and 0.0 to 4.2 ppm BTEX. Two soil treatment methods n the pilot system were implemented; venting to treat the lighter petroleum fractions and bioremediation to treat the nonvolatile petroleum constituents. Seven soil gas probes were installed to monitor pressure and soil gas vapor concentrations in the subsurface. Changes in soil gas oxygen and carbon dioxide concentrations were used as an indirect measure of enhanced bioremediation of pilot cell soils. After operating the system for a period of 2.5 months, soil BTEX concentrations were reduced to concentrations below the remediation criteria for the site

300 Area Treatability Test: Laboratory Development of Polyphosphate Remediation Technology for In Situ Treatment of Uranium Contamination in the Vadose Zone and Capillary Fringe

Energy Technology Data Exchange (ETDEWEB)

Wellman, Dawn M.; Pierce, Eric M.; Bacon, Diana H.; Oostrom, Martinus; Gunderson, Katie M.; Webb, Samuel M.; Bovaird, Chase C.; Cordova, Elsa A.; Clayton, Eric T.; Parker, Kent E.; Ermi, Ruby M.; Baum, Steven R.; Vermeul, Vincent R.; Fruchter, Jonathan S.

2008-09-30

This report presents results from bench-scale treatability studies conducted under site-specific conditions to optimize the polyphosphate amendment for implementation of a field-scale technology demonstration to stabilize uranium within the 300 Area vadose and smear zones of the Hanford Site. The general treatability testing approach consisted of conducting studies with site sediment and under site conditions, to develop an effective chemical formulation and infiltration approach for the polyphosphate amendment under site conditions. Laboratory-scale dynamic column tests were used to 1) quantify the retardation of polyphosphate and its degradation products as a function of water content, 2) determine the rate of polyphosphate degradation under unsaturated conditions, 3) develop an understanding of the mechanism of autunite formation via the reaction of solid phase calcite-bound uranium and aqueous polyphosphate remediation technology, 4) develop an understanding of the transformation mechanism, the identity of secondary phases, and the kinetics of the reaction between uranyl-carbonate and -silicate minerals with the polyphosphate remedy under solubility-limiting conditions, and 5) quantify the extent and rate of uranium released and immobilized based on the infiltration rate of the polyphosphate remedy and the effect of and periodic wet-dry cycling on the efficacy of polyphosphate remediation for uranium in the vadose zone and smear zone.

Spatial and temporal dynamics of organohalide-respiring bacteria in a heterogeneous PCE-DNAPL source zone.

Science.gov (United States)

Cápiro, Natalie L; Löffler, Frank E; Pennell, Kurt D

2015-11-01

Effective treatment of sites contaminated with dense non-aqueous phase liquids (DNAPLs) requires detailed understanding of the microbial community responses to changes in source zone strength and architecture. Changes in the spatial and temporal distributions of the organohalide-respiring Dehalococcoides mccartyi (Dhc) strains and Geobacter lovleyi strain SZ (GeoSZ) were examined in a heterogeneous tetrachloroethene- (PCE-) DNAPL source zone within a two-dimensional laboratory-scale aquifer flow cell. As part of a combined remedy approach, flushing with 2.3 pore volumes (PVs) of 4% (w/w) solution of the nonionic, biodegradable surfactant Tween® 80 removed 55% of the initial contaminant mass, and resulted in a PCE-DNAPL distribution that contained 51% discrete ganglia and 49% pools (ganglia-to-pool ratio of 1.06). Subsequent bioaugmentation with the PCE-to-ethene-dechlorinating consortium BDI-SZ resulted in cis-1,2-dichloroethene (cis-DCE) formation after 1 PV (ca. 7 days), while vinyl chloride (VC) and ethene were detected 10 PVs after bioaugmentation. Maximum ethene yields (ca. 90 μM) within DNAPL pool and ganglia regions coincided with the detection of the vcrA reductive dehalogenase (RDase) gene that exceeded the Dhc 16S rRNA genes by 2.0±1.3 and 4.0±1.7 fold in the pool and ganglia regions, respectively. Dhc and GeoSZ cell abundance increased by up to 4 orders-of-magnitude after 28 PVs of steady-state operation, with 1 to 2 orders-of-magnitude increases observed in close proximity to residual PCE-DNAPL. These observations suggest the involvement of these dechlorinators the in observed PCE dissolution enhancements of up to 2.3 and 6.0-fold within pool and ganglia regions, respectively. Analysis of the solid and aqueous samples at the conclusion of the experiment revealed that the highest VC (≥155 μM) and ethene (≥65 μM) concentrations were measured in zones where Dhc and GeoSZ were predominately attached to the solids. These findings demonstrate

Integrated characterization of natural attenuation of a PCE plume after thermal remediation of the source zone - incl. dual isotope and microbial techniques

DEFF Research Database (Denmark)

Broholm, Mette Martina

dechlorination 1-1.5 km downstream the source area, where the plume descends into more reduced groundwater. The objective of the new (2014) study is to evaluate how the source remediation has impacted the plume and in particular the natural attenuation within the plume. A large monitoring campaign including...... down-gradient which co-inside with the reduction in redox conditions. The findings document a significant increase in cDCE degradation without accumulation of VC. This reduces the risk posed by the contaminant plume to the drinking water resource. This project is unique in the integrated...... area, resulted in the release of dissolved organic matter and some geochemical changes. This has had an effect on redox conditions and biodegradation by reductive dechlorination particularly in the near source area. However, also in the further downstream area of the plume redox and contaminant levels...

Predicting DNAPL Source Zone and Plume Response Using Site-Measured Characteristics

Science.gov (United States)

2017-05-19

Losses must be considered such as complete degradation, changes in hydro -stratigraphy, and remediation. c. Use of Extraction Wells Changes in...coal tar is polyparameter linear free energy relationships which uses a mechanistic description of the intermolecular interactions. Final Report ER...used to identify zones of contamination. There were three electric conductivity logging tools tested: the flame ionization detector (FID), the

Delineation of seismic source zones based on seismicity parameters ...

Indian Academy of Sciences (India)

In the present study, an attempt has been made to delineate seismic source zones in the study area (south India) based on the seismicity parameters. Seismicity parameters and the maximum probable earthquake for these source zones were evaluated and were used in the hazard evaluation. The probabilistic evaluation of ...

Know Your Enemy - Implementation of Bioremediation within a Suspected DNAPL Source Zone Following High-Resolution Site Characterization at Contractors Road Heavy Equipment Area, Kennedy Space Center, Florida

Science.gov (United States)

Chrest, Anne; Daprato, Rebecca; Burcham, Michael; Johnson, Jill

2018-01-01

in concentrations observed additional sampling was conducted in 2016. The results identified higher concentrations than originally detected within the previously defined source area and the presence of source zone concentrations upgradient of the previously defined source area (maximum concentration observed 570,000 micro-g/L). The HRSC baseline sampling data allowed for a revision of the bioremediation design prior to implementation. Bioremediation was implemented within the eastern portion of the source area in November and December 2016 and quarterly performance monitoring was completed in March and June 2017. Reductions in CVOC concentrations from baseline were observed at all performance monitoring wells in the treatment area, and by June 2017, an approximate 95% CVOC mass reduction was observed based on monitoring well sampling results. Results/Lessons Learned: The results of this project suggest that, due to the complexity of DNAPL source zones, HRSC during pre-implementation baseline sampling in the TCE source zone was an essential strategy for verifying the treatment area and depth prior to remedy implementation. If the upgradient source zone mass was not identified prior to bioremediation implementation, the mass would have served as a long-term source for the dissolved plume.

Soil remediation process and system

International Nuclear Information System (INIS)

Monlux, K.J.

1992-01-01

This patent describes a process for remediation of soil containing up to about 30,000 ppm hydrocarbon contaminants. It comprises: providing hydrocarbon-contaminated soil in a divided condition of minus 1 1/2 double-prime to a first confined zone where it is exposed to an open flame; heating while agitating the contaminated soil in an oxidizing atmosphere in the first zone to a temperature below soil ignition within a range of from about 375 degrees F. to about 750 degrees F. for a time sufficient to drive off as vapors a substantial percentage of the hydrocarbon contaminates from the soil; passing hot gases containing the hydrocarbon contaminates from the soil; passing hot gases containing the hydrocarbon vapors from the first zone to a second zone; recovering heat from the hot gases in the second zone to condense a substantial percentage of the hydrocarbon vapors as liquid hydrocarbons; recovering the liquid hydrocarbons; and removing the soil from the first zone as remediated soil having below about 1000 ppm hydrocarbon contaminants

Towards Coated Nano-Gold Particles as Non-Reactive Tracers in Coated nZVI for In-Situ Remediation

DEFF Research Database (Denmark)

Fjordbøge, Annika Sidelmann; Uthuppu, Basil; Caspersen, Eva

2014-01-01

Background/Objectives. Chlorinated solvent (e.g. trichloroethene and tetrachloroethene) source zones in the subsurface pose a continuous threat to groundwater quality at many sites worldwide. Remediation of these contaminated sites is especially challenging in the presence of Dense Non-Aqueous Ph...

Cost of presumptive source term Remedial Actions Laboratory for energy-related health research, University of California, Davis

International Nuclear Information System (INIS)

Last, G.V.; Bagaasen, L.M.; Josephson, G.B.; Lanigan, D.C.; Liikala, T.L.; Newcomer, D.R.; Pearson, A.W.; Teel, S.S.

1995-12-01

A Remedial Investigation/Feasibility Study (RI/FS) is in progress at the Laboratory for Energy Related Health Research (LEHR) at the University of California, Davis. The purpose of the RI/FS is to gather sufficient information to support an informed risk management decision regarding the most appropriate remedial actions for impacted areas of the facility. In an effort to expedite remediation of the LEHR facility, the remedial project managers requested a more detailed evaluation of a selected set of remedial actions. In particular, they requested information on both characterization and remedial action costs. The US Department of Energy -- Oakland Office requested the assistance of the Pacific Northwest National Laboratory to prepare order-of-magnitude cost estimates for presumptive remedial actions being considered for the five source term operable units. The cost estimates presented in this report include characterization costs, capital costs, and annual operation and maintenance (O ampersand M) costs. These cost estimates are intended to aid planning and direction of future environmental remediation efforts

Effect of heterogeneity on enhanced reductive dechlorination: Analysis of remediation efficiency and groundwater acidification

Science.gov (United States)

Brovelli, A.; Lacroix, E.; Robinson, C. E.; Gerhard, J.; Holliger, C.; Barry, D. A.

2011-12-01

Enhanced reductive dehalogenation is an attractive in situ treatment technology for chlorinated contaminants. The process includes two acid-forming microbial reactions: fermentation of an organic substrate resulting in short-chain fatty acids, and dehalogenation resulting in hydrochloric acid. The accumulation of acids and the resulting drop of groundwater pH are controlled by the mass and distribution of chlorinated solvents in the source zone, type of electron donor, alternative terminal electron acceptors available and presence of soil mineral phases able to buffer the pH (such as carbonates). Groundwater acidification may reduce or halt microbial activity, and thus dehalogenation, significantly increasing the time and costs required to remediate the aquifer. In previous work a detailed geochemical and groundwater flow simulator able to model the fermentation-dechlorination reactions and associated pH change was developed. The model accounts for the main processes influencing microbial activity and groundwater pH, including the groundwater composition, the electron donor used and soil mineral phase interactions. In this study, the model was applied to investigate how spatial variability occurring at the field scale affects dechlorination rates, groundwater pH and ultimately the remediation efficiency. Numerical simulations were conducted to examine the influence of heterogeneous hydraulic conductivity on the distribution of the injected, fermentable substrate and on the accumulation/dilution of the acidic products of reductive dehalogenation. The influence of the geometry of the DNAPL source zone was studied, as well as the spatial distribution of soil minerals. The results of this study showed that the heterogeneous distribution of the soil properties have a potentially large effect on the remediation efficiency. For examples, zones of high hydraulic conductivity can prevent the accumulation of acids and alleviate the problem of groundwater acidification. The

Ionization dual-zone static detector having single radioactive source

International Nuclear Information System (INIS)

Ried, L. Jr.; Wade, A.L.

1977-01-01

This ionization detector or combustion product detector includes a single radioactive source located in an ionization chamber, and the ionization chamber includes portions comprising a reference zone and a signal zone. Electrical circuitry connected to the reference and signal zones provides an output signal directly related to changes in voltages across the signal zone in relation to the amount of particulates of combustion present in the ionization chamber

Vadose zone investigations at the Lawrence Livermore National Laboratory Superfund Site: An overview

International Nuclear Information System (INIS)

Iovenitti, J.L.; Nitao, J.J.; Bishop, D.J.

1992-09-01

Lawrence Livermore National Laboratory (LLNL)is investigating the fate and transport of vadose zone contaminants at their Livermore site in Livermore, California. The principal objectives of this work are to identify potential source areas at the Livermore site which require remediation, to prioritize those areas, and finally, to optimize the remediation process. Primary contaminants of interest for this investigation are volatile organic compounds (VOCs) and tritium. A fully integrated, three-part program, consisting of quantitative modeling, field studies, and laboratory measurements, is in progress. To evaluate and predict vadose zone contaminant migration, quantitative modeling is used. Our modeling capabilities are being enhanced through the development of a multicomponent,three-dimensional,nonaqueous phase liquid-liquid-vapor,nonisothermal flow and transport computer code. This code will be also used to evaluate vadose zone remediation requirements. Field studies to acquire LLNL site-specific soil (sediment) characteristics for computer code calibration and validation include subsurf ace lithologic and contaminant profiling, in situ soil moisture content, ground surface emission flux of VOCs and tritium, transpiration of tritium, and ground surface evapotranspiration of water. Multilevel vadose zone monitoring devices are used to monitor the gaseous and aqueous transport of contaminants

A Bayesian Approach to Integrate Real-Time Data into Probabilistic Risk Analysis of Remediation Efforts in NAPL Sites

Science.gov (United States)

Fernandez-Garcia, D.; Sanchez-Vila, X.; Bolster, D.; Tartakovsky, D. M.

2010-12-01

The release of non-aqueous phase liquids (NAPLs) such as petroleum hydrocarbons and chlorinated solvents in the subsurface is a severe source of groundwater and vapor contamination. Because these liquids are essentially immiscible due to low solubility, these contaminants get slowly dissolved in groundwater and/or volatilized in the vadoze zone threatening the environment and public health over a long period. Many remediation technologies and strategies have been developed in the last decades for restoring the water quality properties of these contaminated sites. The failure of an on-site treatment technology application is often due to the unnoticed presence of dissolved NAPL entrapped in low permeability areas (heterogeneity) and/or the remaining of substantial amounts of pure phase after remediation efforts. Full understanding of the impact of remediation efforts is complicated due to the role of many interlink physical and biochemical processes taking place through several potential pathways of exposure to multiple receptors in a highly unknown heterogeneous environment. Due to these difficulties, the design of remediation strategies and definition of remediation endpoints have been traditionally determined without quantifying the risk associated with the failure of such efforts. We conduct a probabilistic risk analysis (PRA) of the likelihood of success of an on-site NAPL treatment technology that easily integrates all aspects of the problem (causes, pathways, and receptors) without doing extensive modeling. Importantly, the method is further capable to incorporate the inherent uncertainty that often exist in the exact location where the dissolved NAPL plume leaves the source zone. This is achieved by describing the failure of the system as a function of this source zone exit location, parameterized in terms of a vector of parameters. Using a Bayesian interpretation of the system and by means of the posterior multivariate distribution, the failure of the

Delineation of seismic source zones based on seismicity parameters ...

Indian Academy of Sciences (India)

these source zones were evaluated and were used in the hazard evaluation. ... seismic sources, linear and areal, were considered in the present study to model the seismic sources in the ..... taken as an authentic reference manual for iden-.

Evaluating time-lapse ERT for monitoring DNAPL remediation via numerical simulation

Science.gov (United States)

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

2012-12-01

Dense non-aqueous phase liquids (DNAPLs) remain a challenging geoenvironmental problem in the near subsurface. Numerous thermal, chemical, and biological treatment methods are being applied at sites but without a non-destructive, rapid technique to map the evolution of DNAPL mass in space and time, the degree of remedial success is difficult to quantify. Electrical resistivity tomography (ERT) has long been presented as highly promising in this context but has not yet become a practitioner's tool due to challenges in interpreting the survey results at real sites where the initial condition (DNAPL mass, DNAPL distribution, subsurface heterogeneity) is typically unknown. Recently, a new numerical model was presented that couples DNAPL and ERT simulation at the field scale, providing a tool for optimizing ERT application and interpretation at DNAPL sites (Power et al., 2011, Fall AGU, H31D-1191). The objective of this study is to employ this tool to evaluate the effectiveness of time-lapse ERT to monitor DNAPL source zone remediation, taking advantage of new inversion methodologies that exploit the differences in the target over time. Several three-dimensional releases of chlorinated solvent DNAPLs into heterogeneous clayey sand at the field scale were generated, varying in the depth and complexity of the source zone (target). Over time, dissolution of the DNAPL in groundwater was simulated with simultaneous mapping via periodic ERT surveys. Both surface and borehole ERT surveys were conducted for comparison purposes. The latest four-dimensional ERT inversion algorithms were employed to generate time-lapse isosurfaces of the DNAPL source zone for all cases. This methodology provided a qualitative assessment of the ability of ERT to track DNAPL mass removal for complex source zones in realistically heterogeneous environments. In addition, it provided a quantitative comparison between the actual DNAPL mass removed and that interpreted by ERT as a function of depth below

Bryophytes - an emerging source for herbal remedies and chemical production

DEFF Research Database (Denmark)

Sabovljevic, Marko S.; Sabovljević, Aneta D.; Ikram, Nur Kusaira K.

2016-01-01

biomass in various ecosystems, bryophytes are a seldom part of ethnomedicine and rarely subject to medicinal and chemical analyses. Still, hundreds of novel natural products have been isolated from bryophytes. Bryophytes have been shown to contain numerous potentially useful natural products, including...... loss, plant growth regulators and allelopathic activities. Bryophytes also cause allergies and contact dermatitis. All these effects highlight bryophytes as potential source for herbal remedies and production of chemicals to be used in various products....

Persulfate injection into a gasoline source zone

Science.gov (United States)

Sra, Kanwartej S.; Thomson, Neil R.; Barker, Jim F.

2013-07-01

One pore volume of unactivated sodium persulfate was delivered into an emplaced gasoline residual source zone at CFB Borden. Concentrations of inorganic species (S2O82 -, SO42 -, Na+, dissolved inorganic carbon (DIC)) and selected gasoline compounds (benzene, toluene, ethylbenzene, xylenes, trimethylbenzenes and naphthalene) were monitored across a transect equipped with 90 multilevel sampling points for > 10 months post-injection. Mass loading (M˙) of compounds constructed from the transect data was used for assessment purposes. Breakthrough of inorganic species was observed when the injection slug crossed the monitoring transect. An increase in M indicated persulfate consumption during oxidation of gasoline compounds or degradation due to the interaction with aquifer materials. M increased by > 100% suggesting some mineralization of gasoline compounds during treatment. Mass loading for all the monitored gasoline compounds reduced by 46 to 86% as the inorganic slug crossed the monitoring transect. The cumulative mass discharge across the monitoring transect was 19 to 58% lower than that expected without persulfate injection. After the inorganic injection slug was flushed from the source zone a partial rebound (40 to 80% of baseline levels) of mass discharge of the monitored gasoline compounds was observed. The ensemble of data collected provides insight into the fate and transport of the injected persulfate solution, and the accompanying treatment of a gasoline the source zone.

Thixotropic gel for vadose zone remediation

Science.gov (United States)

Rhia, Brian D [Augusta, GA

2011-03-01

A thixotropic gel suitable for use in subsurface bioremediation is provided along with a process of using the gel. The thixotropic gel provides a non-migrating injectable substrate that can provide below ground barrier properties. In addition, the gel components provide for a favorable environment in which certain contaminants are preferentially sequestered in the gel and subsequently remediated by either indigenous or introduced microorganisms.

ANNUAL REPORT FOR THE FINAL GROUNDWATER REMEDIATION, TEST AREA NORTH, OPERABLE UNIT 1-07B, FISCAL YEAR 2009

Energy Technology Data Exchange (ETDEWEB)

FORSYTHE, HOWARD S

2010-04-14

This Annual Report presents the data and evaluates the progress of the three-component remedy implemented for remediation of groundwater contamination at Test Area North, Operable Unit 1-07B, at the Idaho National Laboratory Site. Overall, each component is achieving progress toward the goal of total plume remediation. In situ bioremediation operations in the hot spot continue to operate as planned. Progress toward the remedy objectives is being made, as evidenced by continued reduction in the amount of accessible residual source and decreases in downgradient contaminant flux, with the exception of TAN-28. The injection strategy is maintaining effective anaerobic reductive dechlorination conditions, as evidenced by complete degradation of trichloroethene and ethene production in the biologically active wells. In the medial zone, the New Pump and Treat Facility operated in standby mode. Trichloroethene concentrations in the medial zone wells are significantly lower than the historically defined concentration range of 1,000 to 20,000 μg/L. The trichloroethene concentrations in TAN-33, TAN-36, and TAN-44 continue to be below 200 μg/L. Monitoring in the distal zone wells outside and downgradient of the plume boundary demonstrate that some plume expansion has occurred, but less than the amount allowed in the Record of Decision Amendment. Additional data need to be collected for wells in the monitored natural attenuation part of the plume to confirm that the monitored natural attenuation part of the remedy is proceeding as predicted in the modeling.

Persulfate injection into a gasoline source zone.

Science.gov (United States)

Sra, Kanwartej S; Thomson, Neil R; Barker, Jim F

2013-07-01

One pore volume of unactivated sodium persulfate was delivered into an emplaced gasoline residual source zone at CFB Borden. Concentrations of inorganic species (S2O8(2-), SO4(2-), Na(+), dissolved inorganic carbon (DIC)) and selected gasoline compounds (benzene, toluene, ethylbenzene, xylenes, trimethylbenzenes and naphthalene) were monitored across a transect equipped with 90 multilevel sampling points for >10months post-injection. Mass loading (M˙) of compounds constructed from the transect data was used for assessment purposes. Breakthrough of inorganic species was observed when the injection slug crossed the monitoring transect. An increase in [Formula: see text] indicated persulfate consumption during oxidation of gasoline compounds or degradation due to the interaction with aquifer materials. M˙DIC increased by >100% suggesting some mineralization of gasoline compounds during treatment. Mass loading for all the monitored gasoline compounds reduced by 46 to 86% as the inorganic slug crossed the monitoring transect. The cumulative mass discharge across the monitoring transect was 19 to 58% lower than that expected without persulfate injection. After the inorganic injection slug was flushed from the source zone a partial rebound (40 to 80% of baseline levels) of mass discharge of the monitored gasoline compounds was observed. The ensemble of data collected provides insight into the fate and transport of the injected persulfate solution, and the accompanying treatment of a gasoline the source zone. Copyright © 2013 Elsevier B.V. All rights reserved.

Modeling Degradation Product Partitioning in Chlorinated-DNAPL Source Zones

Science.gov (United States)

Boroumand, A.; Ramsburg, A.; Christ, J.; Abriola, L.

2009-12-01

Metabolic reductive dechlorination degrades aqueous phase contaminant concentrations, increasing the driving force for DNAPL dissolution. Results from laboratory and field investigations suggest that accumulation of cis-dichloroethene (cis-DCE) and vinyl chloride (VC) may occur within DNAPL source zones. The lack of (or slow) degradation of cis-DCE and VC within bioactive DNAPL source zones may result in these dechlorination products becoming distributed among the solid, aqueous, and organic phases. Partitioning of cis-DCE and VC into the organic phase may reduce aqueous phase concentrations of these contaminants and result in the enrichment of these dechlorination products within the non-aqueous phase. Enrichment of degradation products within DNAPL may reduce some of the advantages associated with the application of bioremediation in DNAPL source zones. Thus, it is important to quantify how partitioning (between the aqueous and organic phases) influences the transport of cis-DCE and VC within bioactive DNAPL source zones. In this work, abiotic two-phase (PCE-water) one-dimensional column experiments are modeled using analytical and numerical methods to examine the rate of partitioning and the capacity of PCE-DNAPL to reversibly sequester cis-DCE. These models consider aqueous-phase, nonaqueous phase, and aqueous plus nonaqueous phase mass transfer resistance using linear driving force and spherical diffusion expressions. Model parameters are examined and compared for different experimental conditions to evaluate the mechanisms controlling partitioning. Biot number, a dimensionless number which is an index of the ratio of the aqueous phase mass transfer rate in boundary layer to the mass transfer rate within the NAPL, is used to characterize conditions in which either or both processes are controlling. Results show that application of a single aqueous resistance is capable to capture breakthrough curves when DNAPL is distributed in porous media as low

Situating Remediation: Accommodating Success and Failure in Medical Education Systems.

Science.gov (United States)

Ellaway, Rachel H; Chou, Calvin L; Kalet, Adina L

2018-03-01

There has been a widespread shift to competency-based medical education (CBME) in the United States and Canada. Much of the CBME discourse has focused on the successful learner, with relatively little attention paid to what happens in CBME systems when learners stumble or fail. Emerging issues, such as the well-documented problem of "failure to fail" and concerns about litigious learners, have highlighted a need for well-defined and integrated frameworks to support and guide strategic approaches to the remediation of struggling medical learners.This Perspective sets out a conceptual review of current practices and an argument for a holistic approach to remediation in the context of their parent medical education systems. The authors propose parameters for integrating remediation into CBME and describe a model based on five zones of practice along with the rules of engagement associated with each zone. The zones are "normal" curriculum, corrective action, remediation, probation, and exclusion.The authors argue that, by linking and integrating theory and practice in remediation with CBME, a more integrated systems-level response to differing degrees of learner difficulty and failure can be developed. The proposed model demonstrates how educational practice in different zones is based on different rules, roles, responsibilities, and thresholds for moving between zones. A model such as this can help medical educators and medical education leaders take a more integrated approach to learners' failures as well as their successes by being more explicit about the rules of engagement that apply in different circumstances across the competency continuum.

PROBABILISTIC RISK ANALYSIS OF REMEDIATION EFFORTS IN NAPL SITES

Science.gov (United States)

Fernandez-Garcia, D.; de Vries, L.; Pool, M.; Sapriza, G.; Sanchez-Vila, X.; Bolster, D.; Tartakovsky, D. M.

2009-12-01

The release of non-aqueous phase liquids (NAPLs) such as petroleum hydrocarbons and chlorinated solvents in the subsurface is a severe source of groundwater and vapor contamination. Because these liquids are essentially immiscible due to low solubility, these contaminants get slowly dissolved in groundwater and/or volatilized in the vadoze zone threatening the environment and public health over a long period. Many remediation technologies and strategies have been developed in the last decades for restoring the water quality properties of these contaminated sites. The failure of an on-site treatment technology application is often due to the unnoticed presence of dissolved NAPL entrapped in low permeability areas (heterogeneity) and/or the remaining of substantial amounts of pure phase after remediation efforts. Full understanding of the impact of remediation efforts is complicated due to the role of many interlink physical and biochemical processes taking place through several potential pathways of exposure to multiple receptors in a highly unknown heterogeneous environment. Due to these difficulties, the design of remediation strategies and definition of remediation endpoints have been traditionally determined without quantifying the risk associated with the failure of such efforts. We conduct a probabilistic risk assessment of the likelihood of success of an on-site NAPL treatment technology that easily integrates all aspects of the problem (causes, pathways, and receptors). Thus, the methodology allows combining the probability of failure of a remediation effort due to multiple causes, each one associated to several pathways and receptors.

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

Vapor Intrusion Estimation Tool for Unsaturated Zone Contaminant Sources. User’s Guide

Science.gov (United States)

2016-08-30

estimation process when applying the tool. The tool described here is focused on vapor-phase diffusion from the current vadose zone source , and is not...from the current defined vadose zone source ). The estimated soil gas contaminant concentration obtained from the pre-modeled scenarios for a building...need a full site-specific numerical model to assess the impacts beyond the current vadose zone source . 35 5.0 References Brennan, R.A., N

Risk characterization and remedial management of TPH-affected soils

International Nuclear Information System (INIS)

Smith, J.; Von Burg, R.; Preslo, L.; Lakin, M.

1994-01-01

A risk-based remedial program for petroleum hydrocarbon affected soils has been implemented at a large land parcel in California. The site is the former location of a manufacturing facility that had been in operation since the 1940s. As a result of various activities related to parts manufacturing, several large areas of soil were found to contain various petroleum products. The primary sources of petroleum hydrocarbons included cutting oils, lubricating oils, fuels, and hydraulic oils associated with the site operations. Concentrations of total petroleum hydrocarbons (TPH) as high as 100,000 mg/kg were identified in soil. These high concentrations of TPH were identified at depths up to 60 feet below ground surface (bgs), with the vadose zone extending to depths of more than 150 feet bgs. Within California, traditional cleanup levels for TPH-affected soils typically range from 100 to 1,000 mg/kg. Because of the client's desire to sell the property for rapid development, the remedial alternative of excavation and off-haul was deemed too time consuming and costly. The estimated costs associated with this remediation which potentially involved soil removal to 100--120 feet exceeded $20 million and could take up to one year to complete. To meet the schedule requirements for site remediations as well as significantly reduce the overall project cost, the authors undertook a risk-based approach to assess if remediation of the TPH-affected soils was required

Field-scale modeling of acidity production and remediation efficiency during in situ reductive dechlorination

Science.gov (United States)

Brovelli, A.; Robinson, C. E.; Barry, D. A.; Gerhard, J.

2009-12-01

Enhanced reductive dechlorination is a viable technology for in situ remediation of chlorinated solvent DNAPL source areas. Although in recent years increased understanding of this technology has led to more rapid dechlorination rates, complete dechlorination can be hindered by unfavorable conditions. Hydrochloric acid produced from dechlorination and organic acids generated from electron donor fermentation can lead to significant groundwater acidification. Adverse pH conditions can inhibit the activity of dehalogenating microorganisms and thus slow or stall the remediation process. The extent of acidification likely to occur at a contaminated site depends on a number of factors including (1) the extent of dechlorination, (2) the pH-sensitivity of dechlorinating bacteria, and (3) the geochemical composition of the soil and water, in particular the soil’s natural buffering capacity. The substantial mass of solvents available for dechlorination when treating DNAPL source zones means that these applications are particularly susceptible to acidification. In this study a reactive transport biogeochemical model was developed to investigate the chemical and physical parameters that control the build-up of acidity and subsequent remediation efficiency. The model accounts for the site water chemistry, mineral precipitation and dissolution kinetics, electron donor fermentation, gas phase formation, competing electron-accepting processes (e.g., sulfate and iron reduction) and the sensitivity of microbial processes to pH. Confidence in the model was achieved by simulating a well-documented field study, for which the 2-D field scale model was able to reproduce long-term variations of pH, and the concurrent build up of reaction products. Sensitivity analyses indicated the groundwater flow velocity is able to reduce acidity build-up when the rate of advection is comparable or larger than the rate of dechlorination. The extent of pH change is highly dependent on the presence of

Tritium tracer movement as an analogy for pump and treat remediation

International Nuclear Information System (INIS)

1994-12-01

There has been debate over effectiveness of groundwater pump and treat remediation. The goal of the following discussion is to present evidence from a tracer test that illustrates the difficulty in removing contaminants from fractured shale that is typical of portions of the DOE-Oak Ridge Reservation (ORR). This report provides a brief prelude to more detailed analysis that is in progress. Attempts to remediate groundwater contamination with pump and treat technology have been hampered by difficulties in removing contaminants in slow flow zones. There is interest in using this remediation method on the ORR because it is an existing technology. However, this setting provides a rather extreme contrast between fast flow zones (fractures) and slow flow zones (the matrix surrounding the fractures). Over the past few years, the authors have begun to develop an understanding of how contaminants move in fractures and how contaminant exchange between the fracture and matrix occurs. In particular, they have evidence from a long term tritium tracer test that has direct bearing on potential success or failure of pump and treat remediation in fractured rocks

Strategy paper. Remedial design/remedial action 100 Area. Revision 2

International Nuclear Information System (INIS)

Donahoe, R.L.

1995-10-01

This strategy paper identifies and defines the approach for remedial design and remedial action (RD/RA) for source waste sites in the 100 Area of the Hanford Site, located in southeastern Washington State. This paper provides the basis for the US Department of Energy (DOE) to assess and approve the Environmental Restoration Contractor's (ERC) approach to RD/RA. Additionally, DOE is requesting review/agreement from the US Environmental Protection Agency (EPA) and Washington State Department of Ecology (Ecology) on the strategy presented in this document in order to expedite remedial activities

REDUCTION IN ASTHMA MORBIDITY IN CHILDREN AS A RESULT OF HOME REMEDIATION AIMED AT MOISTURE SOURCES

Science.gov (United States)

Objective: Home dampness, presence of mold and allergens have been associated with asthma morbidity. We examined changes in asthma morbidity in children as a result of home remediation aimed at moisture sources.Design: Prospective, randomized controlled trial.Part...

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

Energy Technology Data Exchange (ETDEWEB)

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

1994-12-31

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

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

Energy Technology Data Exchange (ETDEWEB)

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

1993-12-31

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

Oxygenated gasoline release in the unsaturated zone - Part 1: Source zone behavior.

Science.gov (United States)

Freitas, Juliana G; Barker, James F

2011-11-01

Oxygenates present in gasoline, such as ethanol and MTBE, are a concern in subsurface contamination related to accidental spills. While gasoline hydrocarbon compounds have low solubility, MTBE and ethanol are more soluble, ethanol being completely miscible with water. Consequently, their fate in the subsurface is likely to differ from that of gasoline. To evaluate the fate of gasoline containing oxygenates following a release in the unsaturated zone shielded from rainfall/recharge, a controlled field test was performed at Canadian Forces Base Borden, in Ontario. 200L of a mixture composed of gasoline with 10% ethanol and 4.5% MTBE was released in the unsaturated zone, into a trench 20cm deep, about 32cm above the water table. Based on soil cores, most of the ethanol was retained in the source, above the capillary fringe, and remained there for more than 100 days. Ethanol partitioned from the gasoline to the unsaturated pore-water and was retained, despite the thin unsaturated zone at the site (~35cm from the top of the capillary fringe to ground surface). Due to its lower solubility, most of the MTBE remained within the NAPL as it infiltrated deeper into the unsaturated zone and accumulated with the gasoline on top of the depressed capillary fringe. Only minor changes in the distribution of ethanol were noted following oscillations in the water table. Two methods to estimate the capacity of the unsaturated zone to retain ethanol are explored. It is clear that conceptual models for sites impacted by ethanol-fuels must consider the unsaturated zone. Copyright © 2011 Elsevier B.V. All rights reserved.

Emplacement of zero-valent metal for remediation of deep contaminant plumes

International Nuclear Information System (INIS)

Hubble, D.W.; Gillham, R.W.; Cherry, J.A.

1997-01-01

Some groundwater plumes containing chlorinated solvent contaminants are found to be so deep that current in situ remediation technologies cannot be economically applied. Also, source zones are often found to be too deep for removal or inaccessible due to surface features. Plumes emanating from these sources require containment or treatment. Containment technologies are available for shallow sites (< 15 m) and are being developed for greater depths. However, it is important to advance the science of reactive treatment - both for cut off of plumes and to contain and treat source zones. Zero-valent metal technology has been used for remediation of solvent plumes at sites in Canada, the UK and at several industrial and military sites in the USA. To date, all of the plumes treated with zero-valent metal (granular iron) have been at depths less than 15 m. This paper gives preliminary results of research into methods to emplace granular iron at depths in the range of 15 to 60 m. The study included review of available and emerging methods of installing barrier or reactive material and the selection, preliminary design and costing of several methods. The design of a treatment system for a 122 m wide PCE plume that, immediately down gradient from its source, extends from a depth of 24 to 37 m below the ground surface is used as a demonstration site. Both Permeable Reactive Wall and Funnel-and-Gate trademark systems were considered. The emplacement methods selected for preliminary design and costing were slurry wall, driven/vibrated beam, deep soil mixing and hydrofracturing injection. For each of these methods, the iron must be slurried for ease of pumping and placement using biodegradable polymer viscosifiers that leave the iron reactive

Part 2: A field study of enhanced remediation of Toluene in the vadose zone using a nutrient solution

Science.gov (United States)

Tindall, J.A.; Weeks, E.P.; Friedel, M.

2005-01-01

The objective of this study was to test the effectiveness of a nitrate-rich nutrient solution and hydrogen peroxide (H2O2) to enhance in-situ microbial remediation of toluene in the unsaturated zone. Three sand-filled plots were tested in three phases (each phase lasting approximately 2 weeks). During the control phase, toluene was applied uniformly via sprinkler irrigation. Passive remediation was allowed to occur during this phase. A modified Hoagland nutrient solution, concentrated in 150 L of water, was tested during the second phase. The final phase involved addition of 230 moles of H2O2 in 150 L of water to increase the available oxygen needed for aerobic biodegradation. During the first phase, measured toluene concentrations in soil gas were reduced from 120 ppm to 25 ppm in 14 days. After the addition of nutrients during the second phase, concentrations were reduced from 90 ppm to about 8 ppm within 14 days, and for the third phase (H 2O2), toluene concentrations were about 1 ppm after only 5 days. Initial results suggest that this method could be an effective means of remediating a contaminated site, directly after a BTEX spill, without the intrusiveness and high cost of other abatement technologies such as bioventing or soil-vapor extraction. However, further tests need to be completed to determine the effect of each of the BTEX components. ?? Springer 2005.

INDEPENDENT REVIEW OF THE X-701B GROUNDWATER REMEDY, PORTSMOUTH, OHIO: TECHNICAL EVALUATION AND RECOMMENDATIONS

Energy Technology Data Exchange (ETDEWEB)

Looney, B.; Eddy-Dilek, C.; Costanza, J.; Rossabi, J.; Early, T.; Skubal, K.; Magnuson, C.

2008-12-15

recommended, the team should identify the type of injection and target soil horizon for these injections; (2) Consider the feasibility of declaring Technical Impracticability and proceeding with the RCRA Cap for the X-701B; and (3) Provide a summary of other cost-effective technologies that could be implemented (especially for the lower Gallia). The Independent Technical Review team focused its evaluation solely on the X-701B source zone and contaminant plume. It did not review current or planned remedial activities at other plumes, waste areas, or landfills at the Portsmouth site, nor did it attempt to integrate such activities into its recommendations for X-701B. However, the ultimate selection of a remedy for X-701B by site personnel and regulators should take into account potentially synergistic efforts at other waste areas. Assessment of remedial alternatives in the context of site-wide management practices may reveal opportunities for leveraging and savings that would not otherwise be identified. For example, the cost of source-zone excavation or construction of a permeable reactive barrier at X-701B might be substantially reduced if contaminated soil could be buried on site at an existing or planned landfill. This allowance would improve the feasibility and competitiveness of both remedies. A comprehensive examination of ongoing and future environmental activities across the Portsmouth Gaseous Diffusion Plant is necessary to optimize the selection and timing of X-701B remediation with respect to cleanup efficiency, safety, and economics. A selected group of technical experts attended the technical workshop at the Portsmouth Gaseous Diffusion Plant from November 18 through 21, 2008. During the first day of the workshop, both contractor and DOE site personnel briefed the workshop participants and took them on a tour of the X-701B site. The initial briefing was attended by representatives of Ohio EPA who participated in the discussions. On subsequent days, the team

Online data sources for regulation and remediation of chemical production, distribution, use and disposal

International Nuclear Information System (INIS)

Snow, B.; Arnold, S.

1995-01-01

Environmental awareness is essential for todays corporation. Corporations have been held liable for the short-term and long-term effects of such chemicals as pharmaceuticals, agrochemicals and petrochemicals to name a few. Furthermore, corporations have been held accountable for disposal of wastes or by-products of chemical production. Responsibility for the environment either mandated by government agencies or done voluntarily is an economic factor for business operations. Remediation of environmental hazards on a voluntary basis has often created goodwill and a payoff for being socially responsible. Remediation also can result in new business opportunities or savings in production costs. To be environmentally aware and socially responsible, the chemist should know where to find regulatory information for countries worldwide. Using online data sources is an efficient method of seeking this information

CENTRAL PLATEAU REMEDIATION

International Nuclear Information System (INIS)

ROMINE, L.D.

2006-01-01

A systematic approach to closure planning is being implemented at the Hanford Site's Central Plateau to help achieve the goal of closure by the year 2035. The overall objective of Central Plateau remediation is to protect human health and the environment from the significant quantity of contaminated material that resulted from decades of plutonium production in support of the nation's defense. This goal will be achieved either by removing contaminants or placing the residual contaminated materials in a secure configuration that minimizes further migration to the groundwater and reduces the potential for inadvertent intrusion into contaminated sites. The approach to Central Plateau cleanup used three key concepts--closure zones, closure elements, and closure process steps--to create an organized picture of actions required to complete remediation. These actions were merged with logic ties, constraints, and required resources to produce an integrated time-phased schedule and cost profile for Central Plateau closure. Programmatic risks associated with implementation of Central Plateau closure were identified and analyzed. Actions to mitigate the most significant risks are underway while high priority remediation projects continue to make progress

The Geochemical Record of Cultural Eutrophication and Remediation Efforts in Three Connecticut Lakes

Science.gov (United States)

Ku, T.; Bourne, H. L.; Tirtajana, S.; Nahar, M.; Kading, T.

2009-12-01

Cultural eutrophication is the process whereby human activity increases the amount of nutrients, primarily nitrogen and phosphorous, entering an aquatic ecosystem causing excessive biological growth. To reverse or decelerate cultural eutrophication, many regulatory agencies have implemented stringent laws intended to lower the flux of nutrients into impacted water bodies or have emplaced internal remediation systems designed to decrease primary productivity. To quantify the effects of cultural eutrophication and remediation efforts, we examined sedimentary histories of three eutrophic Connecticut lakes that record the transition from pre-anthropogenic conditions into eutrophication and through recent remediation. The three Connecticut lakes (Lake Waramaug, Beseck Lake, and Amos Lake) represent a range of remediation activities. Since 1983, Lake Waramaug has been the focus of significant remediation efforts including the installation of three hypolimnetic withdrawal / layer aeration systems, zoning regulations to limit runoff, and the stocking and seeding of fish and zooplankton. Beseck Lake has experienced episodic eutrophic conditions, in part due to failing septic systems, and in 2001, 433 residences were converted from septic systems to a city sewer system. Amos Lake serves as a cultural eutrophication end member as it has not has received any major remediation. Multiple freeze and gravity cores were collected from 2005-2008. Radiocarbon, Pb-210, Cs-137, Hg, and Pb measurements determined sediment ages. Organic C accumulation rates, C/N ratios, organic matter delta-15N, bulk sediment Fe and Al concentrations, and P speciation (labile, iron-bound, aluminum-bound, organic, and total) determined sediment and nutrient sources and accumulations. Dithionite-extractable iron, pyrite S, and pyrite delta-34S provided insight into changes in P-Fe-S cycling. The sediment cores represent the last few hundreds of years of lake history and, importantly, some Lake Waramaug

Water sources accessed by arid zone riparian trees in highly saline environments, Australia.

Science.gov (United States)

Costelloe, Justin F; Payne, Emily; Woodrow, Ian E; Irvine, Elizabeth C; Western, Andrew W; Leaney, Fred W

2008-05-01

The flow regimes of arid zone rivers are often highly variable, and shallow groundwater in the alluvial aquifers can be very saline, thus constraining the availability and quality of the major water sources available to riparian trees-soil water, shallow groundwater and stream water. We have identified water sources and strategies used by riparian trees in more highly saline and arid conditions than previously studied for riparian trees of arid zone rivers. Our research focused on the riparian species Eucalyptus coolabah, one of the major riparian trees of ephemeral arid zone rivers in Australia. The water sources available to this riparian tree were examined using delta(18)O isotope data from xylem, soil water, groundwater and surface water. Additionally, soil chloride and matric potential data were used to infer zones of water availability for root uptake. Despite the saline conditions, the trees used a mixture of soil water and groundwater sources, but they did not use surface water directly. The study identified three strategies used to cope with typically high groundwater and soil water salinities. Firstly, the trees preferentially grow in zones of most frequent flushing by infiltrating streamflow, such as the bank-tops of channels. Secondly, the trees limit water use by having low transpiration rates. Thirdly, the trees are able to extract water at very low osmotic potentials, with water uptake continuing at chloride concentrations of at least 20,000-30,000 mg L(-1).

In-situ bioaugmentation of vadose zone restoration

International Nuclear Information System (INIS)

Myers, J.M.; Minkel, K.A.; Schepart, B.S.

1992-01-01

Leakage from an underground gasoline storage tank caused evacuation from a restaurant and an insurance company. An engineering consultant was engaged to correct the problem. Upon remedy of the habitability situation, a groundwater recovery system was designed to recover whatever open-quotes free productclose quotes gasoline could be collected. Since traditional open-quotes Pump and treatclose quotes remedial technologies are successful only to the extent that the contaminant is mobile, an alternative is necessary to effectively remediate that contamination which is recalcitrant. At this point, Waste Stream Technology was enlisted to propose an in-situ remedial action plan. Approximately five injection wells were installed around the perimeter and in the zone of influence of each of eight recovery wells. The injection wells were designed to distribute the bacteria at various depths in the vadose zone. Bacteria were cultured on site in Waste Stream's proprietary bioreactor. Bacterial and nutrient applications were injected on a weekly basis. Bacterial population dynamics and BETX levels were monitored throughout the course of the remediation. Although the remediation is currently in progress, disappearance of open-quotes free productclose quotes on the water table and elimination of benzene in the groundwater over a reasonable time period marked the success of this project

Characterization and remediation of highly radioactive contaminated soil at Hanford

International Nuclear Information System (INIS)

Buckmaster, M.A.; Erickson, J.K.

1993-09-01

The Hanford Site, Richland, Washington, contains over 1,500 identified waste sites and numerous groundwater plumes that will be characterized and remediated over the next 30 years. As a result of the Hanford Federal Facility Agreement and Consent Order, the US Department of Energy (DOE) has initiated a remedial investigation/feasibility study (RI/FS) at the 200-BP-1 operable unit. The 200-BP-1 RI/FS is the first Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) investigation on the Hanford Site that involves highly radioactive and chemically contaminated soils. The initial phase of site characterization was designed to assess the nature and extent of contamination associated with the source waste sites within the 200-BP-1 operable unit. Characterization activities consisted of drilling and sampling, chemical and physical analysis of samples, and development of a conceptual vadose zone model. These data were then used. to develop remedial alternatives during the FS evaluation. The preferred alternative resulting from the RI/FS process for the 200-BP-1 operable unit is to construct a surface isolation barrier. The multi-layered earthen barrier will be designed to prevent migration of contaminants resulting from water infiltration, biointrusion, and wind and water erosion

Comparison of doses, before and after remedial action

International Nuclear Information System (INIS)

Wallo, A. III

1988-01-01

The Division of Facility and Site Decommissioning Projects at DOE-Headquarters is evaluating potential doses from vicinity properties before and after remedial action at several sites using the RESRAD computer code. A preliminary review was completed for nineteen Colonie vicinity properties. This review indicated potential doses before remedial action at these sites ranged from about 43 to 2 mrem/year and after remediation between 5 and 0 mrem/year. These estimates indicate the conservatism in the DOE-derived soil decontamination remedial action. Following remedial action, the potential doses are on the order of those being considered to be below regulatory concern by EPA and NRC. The estimates made for these sites are still conservative due to the method used to determine the source term. More realistic assessments of source terms are anticipate dot significantly affect the after-remedial-action doses, possibly lowering them all to below 1 mrem/year. This evaluation is being refined with more realistic estimates of the source term, for all of the Colonie vicinity properties. Once the Colonie vicinity properties are completed, at least three other sites will be evaluated. It is hoped that this information will provide added confidence in the remedial action guidelines and more general acceptance of the guidelines by the EPA and others

Installation of an innovative remedial technology

International Nuclear Information System (INIS)

Hines, B.

1995-01-01

The major goal of the Lasagna trademark project was to design, construct, install, and operate an in situ remediation system in low-permeability soil. A new technology--the Lasagna process--uses electro-osmosis to move contaminated groundwater through treatment zones. The treatment zones are installed in contaminated soils, thereby forming an integrated in situ remedial process. Electro-osmosis, well known for its effectiveness and extremely low power consumption, uses a direct current to cause Groundwater to travel through low-permeability soil. When a bench-scale version of the technology was 98 percent effective in removing contamination, an actual field test was the next step. The site chosen for this first field effort was the DOE-owned Paducah Gaseous Diffusion Plant located in Paducah, Kentucky. The target contaminant for this project was trichloroethylene (TCE) because it is found at many sites across the country and is present at approximately 60 percent of DOE's sites

Advances in vacuum extraction technology for effective subsurface remediation

International Nuclear Information System (INIS)

Dodson, M.E.; Pezzullo, J.A.; Piniewski, R.J.

1994-01-01

Vacuum extraction technology has become one of the most widely acclaimed methods for remediating soils contaminated by petroleum hydrocarbons and volatile organic compounds. Removal of the source of contamination in the soil is often the first step in effective control of groundwater contamination. Though originally thought effective only for removal of light-end hydrocarbons from permeable vadose-zone soils, vacuum extraction can now be adapted to address situations of low-permeable soils, heavier-end hydrocarbons and groundwater contamination. This paper reviews four innovative modifications to the vacuum extraction process and how they solve a wide variety of subsurface contamination problems. The modifications, or processes, reviewed include: vacuum-extraction-enhanced bioremediation, groundwater sparging, pneumatic soil fracturing, and soil heating

The 100-C-7 Remediation Project. An Overview of One of DOE's Largest Remediation Projects - 13260

International Nuclear Information System (INIS)

Post, Thomas C.; Strom, Dean; Beulow, Laura

2013-01-01

The U.S. Department of Energy Richland Operations Office (RL), U.S. Environmental Protection Agency (EPA) and Washington Closure Hanford LLC (WCH) completed remediation of one of the largest waste sites in the U.S. Department of Energy complex. The waste site, 100-C-7, covers approximately 15 football fields and was excavated to a depth of 85 feet (groundwater). The project team removed a total of 2.3 million tons of clean and contaminated soil, concrete debris, and scrap metal. 100-C-7 lies in Hanford's 100 B/C Area, home to historic B and C Reactors. The waste site was excavated in two parts as 100-C-7 and 100-C-7:1. The pair of excavations appear like pit mines. Mining engineers were hired to design their tiered sides, with safety benches every 17 feet and service ramps which allowed equipment access to the bottom of the excavations. The overall cleanup project was conducted over a span of almost 10 years. A variety of site characterization, excavation, load-out and sampling methodologies were employed at various stages of remediation. Alternative technologies were screened and evaluated during the project. A new method for cost effectively treating soils was implemented - resulting in significant cost savings. Additional opportunities for minimizing waste streams and recycling were identified and effectively implemented by the project team. During the final phase of cleanup the project team applied lessons learned throughout the entire project to address the final, remaining source of chromium contamination. The C-7 cleanup now serves as a model for remediating extensive deep zone contamination sites at Hanford. (authors)

Deep Vadose Zone-Applied Field Research Initiative Fiscal Year 2011 Annual Report

International Nuclear Information System (INIS)

Wellman, Dawn M.; Johnson, Timothy C.; Smith, Ronald M.; Truex, Michael J.; Matthews, Hope E.

2011-01-01

This annual report describes the background of the Deep Vadose Zone-Applied Field Research Initiative, and some of the programmatic approaches and transformational technologies in groundwater and deep vadose zone remediation developed during fiscal year 2011. The Department of Energy (DOE) Office of Technology Innovation and Development's (OTID) mission is to transform science into viable solutions for environmental cleanup. In 2010, OTID developed the Impact Plan, Science and Technology to Reduce the Life Cycle Cost of Closure to outline the benefits of research and development of the lifecycle cost of cleanup across the DOE complex. This plan outlines OTID's ability to reduce by $50 billion, the $200 billion life-cycle cost in waste processing, groundwater and soil, nuclear materials, and deactivation and decommissioning. The projected life-cycle costs and return on investment are based on actual savings realized from technology innovation, development, and insertion into remedial strategies and schedules at the Fernald, Mound, and Ashtabula sites. To achieve our goals, OTID developed Applied Field Research Initiatives to facilitate and accelerate collaborative development and implementation of new tools and approaches that reduce risk, cost and time for site closure. The primary mission of the Deep Vadose Zone-Applied Field Research Initiative (DVZ-AFRI) is to protect our nation's water resources, keeping them clean and safe for future generations. The DVZ-AFRI was established for the DOE to develop effective, science-based solutions for remediating, characterizing, monitoring, and predicting the behavior and fate of deep vadose zone contamination. Subsurface contaminants include radionuclides, metals, organics, and liquid waste that originated from various sources, including legacy waste from the nation's nuclear weapons complexes. The DVZ-AFRI project team is translating strategy into action by working to solve these complex challenges in a collaborative

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.

Vadose zone characterization of highly radioactive contaminated soil at the Hanford Site

International Nuclear Information System (INIS)

Buckmaster, M.A.

1993-05-01

The Hanford Site in south-central Washington State contains over 1500 identified waste sites and numerous groundwater plumes that will be characterized and remediated over the next 30 years. As a result of the Hanford Federal Facility Agreement and Consent Order, the US Department of Energy has initiated a remedial investigation/feasibility study at the 200-BP-1 operable unit. The 200-BP-1 remedial investigation is the first Comprehensive Environmental Response, Compensation, and Liability Act of 1980 investigation on the Hanford Site that involves drilling into highly radioactive and chemically contaminated soils. The initial phase of site characterization was designed to assess the nature and extent of contamination associated with the source waste site within the 200-BP-1 operable unit. Characterization activities consisted of drilling and sampling the waste site, chemical and physical analysis of samples, and development of a conceptual vadose zone model. Predicted modeling concentrations compared favorably to analytical data collected during the initial characterization activities

Potential of arid zone vegetation as a source of substrates

Energy Technology Data Exchange (ETDEWEB)

Bassham, J.A.

1977-11-01

Three aspects of the potential of vegetation in arid zones as a source of substrates are discussed. The first includes the limitations on efficiency of conversion of solar energy to the stored chemical energy of biomass in green plants, and the subsequent biochemical pathways of carbon dioxide fixation and biosynthesis. Second is the potential of plants endogenous to arid zones. Finally, the use of covered agriculture or controlled environmental agriculture (CEA) is considered both in its present form and in terms of possible extenion to the large scale production of stable crops. (JGB)

Soil remediation via bioventing, vapor extraction and transition regime between vapor extraction and bioventing

Directory of Open Access Journals (Sweden)

Mohammad Mehdi Amin

2014-01-01

Conclusion: Comparison of the BV, SVE and AIBV technologies indicated that all of those technologies are efficient for remediation of unsaturated zone, but after specific remediation time frames, only AIBV able to support guide line values and protect ground waters.

Sandia National Laboratories Chemical Waste Landfill: Innovative strategies towards characterization and remediation

International Nuclear Information System (INIS)

Ardito, Cynthia P.; Parsons, Alva M.; Lindgren, Eric R.; Phelan, James M.; Mattson, Earl D.

1992-01-01

The Chemical Waste Landfill (CWL) was used by Sandia National Laboratories (SNL), Albuquerque for disposal of hazardous chemicals from the years 1962 to 1985. During routine sampling in the spring of 1990, low levels of trichloroethylene (TCE) were detected in groundwater samples from a water table aquifer approximately 146 meters below ground surface. Therefore, a RCRA Site Investigation (RSI) has been initiated and remediation of organic contaminants will be performed at the CWL prior to closure of this landfill. The RSI is focused on optimal characterization of the volatile organic contamination (VOC) and dense non-aqueous phase liquid (DNAPL) contamination at this site. This will be possible through application of innovative strategies for characterization and promising new technologies which are discussed in this paper. The first part of this paper provides a discussion of conceptual models of VOC and DNAPL transport at the CWL and an overview of our investigative strategy. Each stage of the RSI has been developed to gather information which will reduce the uncertainty in the design of each subsequent phase of the investigation. Three stages are described; a source characterization stage, unsaturated zone characterization stage, and a saturated zone characterization stage. An important focus of the unsaturated zone characterization phase is to provide all data necessary to make decisions concerning the necessity of additional saturated zone characterization. The second part of this paper presents a brief discussion of some innovative approaches to characterization and remediation that are being applied at the CWL. Through the. SNL Environmental Restoration Program's desire to find new and improved methods for site characterization and remediation, several innovative technologies have been identified. These technologies include: the surface towed arrays developed by the Naval Research Laboratory for use in locating buried ordinance, core drilling using sonic

Use of Interface Treatment to Reduce Emissions from Residuals in Lower Permeability Zones to Groundwater flowing Through More Permeable Zones (Invited)

Science.gov (United States)

Johnson, P.; Cavanagh, B.; Clifton, L.; Daniels, E.; Dahlen, P.

2013-12-01

Many soil and groundwater remediation technologies rely on fluid flow for contaminant extraction or reactant delivery (e.g., soil vapor extraction, pump and treat, in situ chemical oxidation, air sparging, enhanced bioremediation). Given that most unconsolidated and consolidated settings have permeability contrasts, the outcome is often preferential treatment of more permeable zones and ineffective treatment of the lower permeability zones. When this happens, post-treatment contaminant emissions from low permeability zone residuals can cause unacceptable long-term impacts to groundwater in the transmissive zones. As complete remediation of the impacted lower permeability zones may not be practicable with conventional technologies, one might explore options that lead to reduction of the contaminant emissions to acceptable levels, rather than full remediation of the lower permeability layers. This could be accomplished either by creating a sustained emission reaction/attenuation zone at the high-low permeability interface, or by creating a clean soil zone extending sufficiently far into the lower permeability layer to cause the necessary reduction in contaminant concentration gradient and diffusive emission. These options are explored in proof-of-concept laboratory-scale physical model experiments. The physical models are prepared with two layers of contrasting permeability and either dissolved matrix storage or nonaqueous phase liquid (NAPL) in the lower permeability layer. A dissolved oxidant is then delivered to the interface via flow across the higher permeability layer and changes in contaminant emissions from the low permeability zone are monitored before, during, and after oxidant delivery. The use of three oxidants (dissolved oxygen, hydrogen peroxide and sodium persulfate) for treatment of emissions from petroleum hydrocarbon residuals is examined.

Screening and comparison of remedial alternatives for the South Field and flyash piles at the Fernald site

International Nuclear Information System (INIS)

Bumb, A.C.; Jones, G.N.

1996-05-01

The South Field, the Inactive Flyash Pile, and the Active Flyash Pile are in close proximity to each other and are part of Operable Unit 2 (OU2) at the Fernald Environmental Management Project (FEMP). The baseline risk assessment indicated that the exposure pathways which pose the most significant risk are external radiation from radionuclides in surface soils and use of uranium contaminated groundwater. This paper presents screening and comparison of various remedial alternatives considered to mitigate risks from the groundwater pathway. Eight remedial alternatives were developed which consisted of consolidation and capping, excavation and off-site disposal with or without treatment, excavation and on-site disposal with or without treatment and combinations of these. Risk-based source (soil) preliminary remediation levels (PRLs) and waste acceptance criteria (WACs) were developed for consolidation and capping, excavation, and on-site disposal cell. The PRLs and WACs were developed using an integrated modeling tool consisting of an infiltration model, a surface water model, a vadose zone model, and a three-dimensional contaminant migration model in saturated media. The PRLs and WACs were then used to determine need for soil treatment, determine excavation volumes, and screen remedial alternatives. The selected remedial alternative consisted of excavation and on-site disposal with off-site disposal of the fraction exceeding the WAC

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

Fresnel zone plate imaging of a 252Cf spontaneous fission source

International Nuclear Information System (INIS)

Stalker, K.T.; Hessel, K.R.

1976-11-01

The feasibility of coded aperture imaging for nuclear fuel motion monitoring is shown using Cf 252 spontaneous fission source. The theory of coded aperture imaging for Fresnel zone plate apertures is presented and design considerations for zone plate construction are discussed. Actual images are obtained which demonstrate a transverse resolution of 1.7 mm and a tomographic resolution of 1.5 millimeters. The capability of obtaining images through 12.7 mm of stainless steel is also shown

World-first PRB remediation system

International Nuclear Information System (INIS)

Mundle, Keely

2013-01-01

Full text: The permeable reactive barrier (PRB) project in question was a former waste control site at Bellevue in Western Australia, which burned down in 2001. The fire and the site's historic use as a liquid waste treatment plant created a plume of contaminated groundwater as well as a secondary offsite plume of chlorinated solvents. Damage from the fire and historical use caused the contamination to extend 200m downgradient of the site, under several nearby parcels of land and migrating in the direction of the nearby Helena River. Two areas of chlorinated solvents were identified as residual dense non-aqueous phase liquid (DNAPL) in the unsaturated zone, including concentrations of trichloroethene (TCE) at 1000 micrograms per litre (μg/L) in groundwater, which needed to be reduced to concentrations of around 330μg/L before the groundwater discharged into the river. Complete source removal of DNAPL contamination - such as TCE - in the environment can be difficult and costly. Partial source removal of the contamination may not have a significant impact on the extent of the plume but may reduce its longevity. Treatment of the contaminant plume is more achievable and allows for more time to develop an effective source remediation solution if it is required. Zero-valent iron (ZVI), a non-toxic granular material placed in PRBs, has been proven to be successful in removing a broad range of contaminants, including many chlorinated solvents such as TCE. In a ZVI-based PRB, the system uses the natural groundwater flow to channel contaminants to an engineered treatment area. As groundwater passes through the PRB, contaminants are treated in the barrier and remediated water flows out the other side. There are two primary pathways for the dechlorination of chlorinated ethenes in ZVI PRBs: beta-elimination and hydrogenolysis. Experiments have shown the dominant degradation pathway is p-elimination. This pathway is preferred as it results in the chlorinated ethene

Deep vadose zone remediation: technical and policy challenges, opportunities, and progress in achieving cleanup endpoints

International Nuclear Information System (INIS)

Wellman, D.M.; Freshley, M.D.; Truex, M.J.; Lee, M.H.

2013-01-01

Current requirements for site remediation and closure are standards-based and are often overly conservative, costly, and in some cases, technically impractical. Use of risk-informed alternate endpoints provides a means to achieve remediation goals that are permitted by regulations and are protective of human health and the environment. Alternate endpoints enable the establishment of a path for cleanup that may include intermediate remedial milestones and transition points and/or regulatory alternatives to standards-based remediation. A framework is presented that is centered around developing and refining conceptual models in conjunction with assessing risks and potential endpoints as part of a system-based assessment that integrates site data with scientific understanding of processes that control the distribution and transport of contaminants in the subsurface and pathways to receptors. This system-based assessment and subsequent implementation of the remediation strategy with appropriate monitoring are targeted at providing a holistic approach to addressing risks to human health and the environment. This holistic approach also enables effective predictive analysis of contaminant behavior to provide defensible criteria and data for making long-term decisions. Developing and implementing an alternate endpoint-based approach for remediation and waste site closure presents a number of challenges and opportunities. Categories of these challenges include scientific and technical, regulatory, institutional, and budget and resource allocation issues. Opportunities exist for developing and implementing systems-based approaches with respect to supportive characterization, monitoring, predictive modeling, and remediation approaches. (authors)

Deep vadose zone remediation: technical and policy challenges, opportunities, and progress in achieving cleanup endpoints

Energy Technology Data Exchange (ETDEWEB)

Wellman, D.M.; Freshley, M.D.; Truex, M.J.; Lee, M.H. [Pacific Northwest National Laboratory, Richland, Washington (United States)

2013-07-01

Current requirements for site remediation and closure are standards-based and are often overly conservative, costly, and in some cases, technically impractical. Use of risk-informed alternate endpoints provides a means to achieve remediation goals that are permitted by regulations and are protective of human health and the environment. Alternate endpoints enable the establishment of a path for cleanup that may include intermediate remedial milestones and transition points and/or regulatory alternatives to standards-based remediation. A framework is presented that is centered around developing and refining conceptual models in conjunction with assessing risks and potential endpoints as part of a system-based assessment that integrates site data with scientific understanding of processes that control the distribution and transport of contaminants in the subsurface and pathways to receptors. This system-based assessment and subsequent implementation of the remediation strategy with appropriate monitoring are targeted at providing a holistic approach to addressing risks to human health and the environment. This holistic approach also enables effective predictive analysis of contaminant behavior to provide defensible criteria and data for making long-term decisions. Developing and implementing an alternate endpoint-based approach for remediation and waste site closure presents a number of challenges and opportunities. Categories of these challenges include scientific and technical, regulatory, institutional, and budget and resource allocation issues. Opportunities exist for developing and implementing systems-based approaches with respect to supportive characterization, monitoring, predictive modeling, and remediation approaches. (authors)

Use of LCA as decision support for the selection of remedial strategies for remediation of contaminated soil and groundwater

DEFF Research Database (Denmark)

Lemming, Gitte; Hauschild, Michael Zwicky; Bjerg, Poul Løgstrup

2009-01-01

, there is a trade-off between obtaining local beneficial effects from the remediation and generating environmental impacts on the regional and global scale due to the remedial actions. Therefore there is a need for including the impact of soil contaminants that will potentially leach to the groundwater, e......Groundwater is the dominant source of drinking water in Denmark and the general policy is to maintain the groundwater as a clean source of drinking water. The risk of groundwater contamination is therefore often the prime reason for remediating a contaminated site. Chlorinated solvents are among...... the contaminants most frequently found to be threatening the groundwater quality in Denmark and worldwide. Life cycle assessment has recently been applied as part of decision support for contaminated site management and subsurface remediation techniques. Impacts in the groundwater compartment have only gained...

Case study of an approved corrective action integrating active remediation with intrinsic remediation

International Nuclear Information System (INIS)

Teets, D.B.; Guest, P.R.; Blicker, B.R.

1996-01-01

Parsons Engineering Science, Inc., performed UST removals and/or site assessments at UST system locations at a former US Air Force Base (AFB) in Denver, Colorado. Four UST systems, incorporating 17 USTs, were located within the petroleum, oils, and lubricants bulk storage yard (POL Yard) of the former AFB. During the tank removals and subsequent site investigations, petroleum hydrocarbon contamination was found in soils at each site. Significant releases from two of the UST systems resulted in a dissolved benzene, toluene, ethylbenzene, and xylenes (BTEX) plume in the groundwater, and smear-zone contamination of soils beneath the majority of the POL Yard. Because of the close proximity of the UST systems, and the presence of the groundwater plume beneath the POL Yard, a corrective action plan (CAP) was prepared that encompassed all four UST systems. An innovative, risk-based CAP integrated active remediation of petroleum-contaminated soils with intrinsic remediation of groundwater. A natural attenuation evaluation for the dissolved BTEX was performed to demonstrate that natural attenuation processes are providing adequate remediation of groundwater and to predict the fate of the groundwater plume. BTEX concentrations versus distance were regressed to obtain attenuation rates, which were then used to calculate BTEX degradation rates using a one-dimensional, steady-state analytical solution. Additionally, electron acceptor concentrations in groundwater were compared to BTEX concentrations to provide evidence that natural attenuation of BTEX compounds was occurring. The natural attenuation evaluation was used in the CAP to support the intrinsic remediation with long-term monitoring alternative for groundwater, thereby avoiding the installation of an expensive groundwater remediation system

The 100-C-7 Remediation Project. An Overview of One of DOE's Largest Remediation Projects - 13260

Energy Technology Data Exchange (ETDEWEB)

Post, Thomas C. [U.S. Department of Energy Richland Operations Office, Richland, WA 99352 (United States); Strom, Dean [Washington Closure Hanford LLC, 2620 Fermi Avenue, Richland, WA 99354 (United States); Beulow, Laura [U.S. Environmental Protection Agency, 309 Bradley Boulevard, Suite 115, Richland, WA 99352 (United States)

2013-07-01

The U.S. Department of Energy Richland Operations Office (RL), U.S. Environmental Protection Agency (EPA) and Washington Closure Hanford LLC (WCH) completed remediation of one of the largest waste sites in the U.S. Department of Energy complex. The waste site, 100-C-7, covers approximately 15 football fields and was excavated to a depth of 85 feet (groundwater). The project team removed a total of 2.3 million tons of clean and contaminated soil, concrete debris, and scrap metal. 100-C-7 lies in Hanford's 100 B/C Area, home to historic B and C Reactors. The waste site was excavated in two parts as 100-C-7 and 100-C-7:1. The pair of excavations appear like pit mines. Mining engineers were hired to design their tiered sides, with safety benches every 17 feet and service ramps which allowed equipment access to the bottom of the excavations. The overall cleanup project was conducted over a span of almost 10 years. A variety of site characterization, excavation, load-out and sampling methodologies were employed at various stages of remediation. Alternative technologies were screened and evaluated during the project. A new method for cost effectively treating soils was implemented - resulting in significant cost savings. Additional opportunities for minimizing waste streams and recycling were identified and effectively implemented by the project team. During the final phase of cleanup the project team applied lessons learned throughout the entire project to address the final, remaining source of chromium contamination. The C-7 cleanup now serves as a model for remediating extensive deep zone contamination sites at Hanford. (authors)

Approaches for assessing sustainable remediation

DEFF Research Database (Denmark)

Søndergaard, Gitte Lemming; Binning, Philip John; Bjerg, Poul Løgstrup

Sustainable remediation seeks to reduce direct contaminant point source impacts on the environment, while minimizing the indirect cost of remediation to the environment, society and economy. This paper presents an overview of available approaches for assessing the sustainability of alternative...... remediation strategies for a contaminated site. Most approaches use multi-criteria assessment methods (MCA) to structure a decision support process. Different combinations of environmental, social and economic criteria are employed, and are assessed either in qualitative or quantitative forms with various...... tools such as life cycle assessment and cost benefit analysis. Stakeholder involvement, which is a key component of sustainable remediation, is conducted in various ways. Some approaches involve stakeholders directly in the evaluation or weighting of criteria, whereas other approaches only indirectly...

40 CFR 85.1803 - Remedial Plan.

Science.gov (United States)

2010-07-01

... POLLUTION FROM MOBILE SOURCES Recall Regulations § 85.1803 Remedial Plan. (a) When any manufacturer is... the total parts requirement of each person who is to perform the repair under the remedial plan to be...: (i) The recall campaign number; and (ii) A code designating the campaign facility at which the repair...

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.

Impacts of beach wrack removal via grooming on surf zone water quality.

Science.gov (United States)

Russell, Todd L; Sassoubre, Lauren M; Zhou, Christina; French-Owen, Darien; Hassaballah, Abdulrahman; Boehm, Alexandria B

2014-02-18

Fecal indicator bacteria (FIB) are used to assess the microbial water quality of recreational waters. Increasingly, nonfecal sources of FIB have been implicated as causes of poor microbial water quality in the coastal environment. These sources are challenging to quantify and difficult to remediate. The present study investigates one nonfecal FIB source, beach wrack (decaying aquatic plants), and its impacts on water quality along the Central California coast. The prevalence of FIB on wrack was studied using a multibeach survey, collecting wrack throughout Central California. The impacts of beach grooming, to remove wrack, were investigated at Cowell Beach in Santa Cruz, California using a long-term survey (two summers, one with and one without grooming) and a 48 h survey during the first ever intensive grooming event. FIB were prevalent on wrack but highly variable spatially and temporally along the nine beaches sampled in Central California. Beach grooming was generally associated with either no change or a slight increase in coastal FIB concentrations and increases in surf zone turbidity and silicate, phosphate, and dissolved inorganic nitrogen concentrations. The findings suggest that beach grooming for wrack removal is not justified as a microbial pollution remediation strategy.

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

Successful application of lead isotopes in source apportionment, legal proceedings, remediation and monitoring.

Science.gov (United States)

Gulson, Brian; Korsch, Michael; Winchester, Wayne; Devenish, Matthew; Hobbs, Thad; Main, Cleve; Smith, Gerard; Rosman, Kevin; Howearth, Lynette; Burn-Nunes, Laurie; Seow, Jimmy; Oxford, Cameron; Yun, Gracie; Gillam, Lindsay; Crisp, Michelle

2012-01-01

In late 2006, the seaside community in Esperance Western Australia was alerted to thousands of native bird species dying. The source of the lead (Pb) was determined by Pb isotopes to derive from the handling of Pb carbonate concentrate through the Port, which began in July 2005. Concern was expressed for the impact of this on the community. Our objectives were to employ Pb isotope ratios to evaluate the source of Pb in environmental samples for use in legal proceedings, and for use in remediation and monitoring. Isotope measurements were undertaken of bird livers, plants, drinking water, soil, harbour sediments, air, bulk ceiling dust, gutter sludge, surface swabs and blood. The unique lead isotopic signature of the contaminating Pb carbonate enabled diagnostic apportionment of lead in samples. Apart from some soil and water samples, the proportion of contaminating Pb was >95% in the environmental samples. Lead isotopes were critical in resolving legal proceedings, are being used in the remediation of premises, were used in monitoring of workers involved in the decontamination of the storage facility, and monitoring transport of the concentrate through another port facility. Air samples show the continued presence of contaminant Pb, more than one year after shipping of concentrate ceased, probably arising from dust resuspension. Brief details of the comprehensive testing and cleanup of the Esperance community are provided along with the role of the Community. Lead isotopic analyses can provide significant benefits to regulatory agencies, interested parties, and the community where the signature is able to be characterised with a high degree of certainty. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

Successful application of lead isotopes in source apportionment, legal proceedings, remediation and monitoring

Energy Technology Data Exchange (ETDEWEB)

Gulson, Brian, E-mail: brian.gulson@mq.edu.au [Graduate School of the Environment, Faculty of Science, Macquarie University, Sydney, NSW 2109 (Australia); CSIRO Earth Science and Resource Engineering North Ryde, NSW 1670 (Australia); Korsch, Michael [CSIRO Earth Science and Resource Engineering North Ryde, NSW 1670 (Australia); Winchester, Wayne; Devenish, Matthew; Hobbs, Thad [Esperance Cleanup and Recovery Project, Western Australia (WA) Department of Transport, Esperance 6450 (Australia); Main, Cleve; Smith, Gerard [Animal Health Laboratory, Department of Agriculture and Food, Perth 6151, WA (Australia); Rosman, Kevin; Howearth, Lynette; Burn-Nunes, Laurie [Curtin University, Department of Imaging and Applied Physics, Bentley 6102, WA (Australia); Seow, Jimmy; Oxford, Cameron [Department of Environment and Conservation, Booragoon 6154, WA (Australia); Yun, Gracie; Gillam, Lindsay [Department of Health, East Perth 6004, WA (Australia); Crisp, Michelle [LED (Locals for Esperance Development), Esperance 6450, WA (Australia)

2012-01-15

In late 2006, the seaside community in Esperance Western Australia was alerted to thousands of native bird species dying. The source of the lead (Pb) was determined by Pb isotopes to derive from the handling of Pb carbonate concentrate through the Port, which began in July 2005. Concern was expressed for the impact of this on the community. Our objectives were to employ Pb isotope ratios to evaluate the source of Pb in environmental samples for use in legal proceedings, and for use in remediation and monitoring. Isotope measurements were undertaken of bird livers, plants, drinking water, soil, harbour sediments, air, bulk ceiling dust, gutter sludge, surface swabs and blood. The unique lead isotopic signature of the contaminating Pb carbonate enabled diagnostic apportionment of lead in samples. Apart from some soil and water samples, the proportion of contaminating Pb was >95% in the environmental samples. Lead isotopes were critical in resolving legal proceedings, are being used in the remediation of premises, were used in monitoring of workers involved in the decontamination of the storage facility, and monitoring transport of the concentrate through another port facility. Air samples show the continued presence of contaminant Pb, more than one year after shipping of concentrate ceased, probably arising from dust resuspension. Brief details of the comprehensive testing and cleanup of the Esperance community are provided along with the role of the Community. Lead isotopic analyses can provide significant benefits to regulatory agencies, interested parties, and the community where the signature is able to be characterised with a high degree of certainty. - Highlights: Black-Right-Pointing-Triangle Lead carbonate concentrate. Black-Right-Pointing-Triangle Successful use of Pb isotopes in identifying sources of Pb arising from transport and shipping. Black-Right-Pointing-Triangle Use of Pb isotopes in legal proceedings and their use in cleanup of residences. Black

Modeling the influence of coupled mass transfer processes on mass flux downgradient of heterogeneous DNAPL source zones.

Science.gov (United States)

Yang, Lurong; Wang, Xinyu; Mendoza-Sanchez, Itza; Abriola, Linda M

2018-04-01

Sequestered mass in low permeability zones has been increasingly recognized as an important source of organic chemical contamination that acts to sustain downgradient plume concentrations above regulated levels. However, few modeling studies have investigated the influence of this sequestered mass and associated (coupled) mass transfer processes on plume persistence in complex dense nonaqueous phase liquid (DNAPL) source zones. This paper employs a multiphase flow and transport simulator (a modified version of the modular transport simulator MT3DMS) to explore the two- and three-dimensional evolution of source zone mass distribution and near-source plume persistence for two ensembles of highly heterogeneous DNAPL source zone realizations. Simulations reveal the strong influence of subsurface heterogeneity on the complexity of DNAPL and sequestered (immobile/sorbed) mass distribution. Small zones of entrapped DNAPL are shown to serve as a persistent source of low concentration plumes, difficult to distinguish from other (sorbed and immobile dissolved) sequestered mass sources. Results suggest that the presence of DNAPL tends to control plume longevity in the near-source area; for the examined scenarios, a substantial fraction (43.3-99.2%) of plume life was sustained by DNAPL dissolution processes. The presence of sorptive media and the extent of sorption non-ideality are shown to greatly affect predictions of near-source plume persistence following DNAPL depletion, with plume persistence varying one to two orders of magnitude with the selected sorption model. Results demonstrate the importance of sorption-controlled back diffusion from low permeability zones and reveal the importance of selecting the appropriate sorption model for accurate prediction of plume longevity. Large discrepancies for both DNAPL depletion time and plume longevity were observed between 2-D and 3-D model simulations. Differences between 2- and 3-D predictions increased in the presence of

Modeling the influence of coupled mass transfer processes on mass flux downgradient of heterogeneous DNAPL source zones

Science.gov (United States)

Yang, Lurong; Wang, Xinyu; Mendoza-Sanchez, Itza; Abriola, Linda M.

2018-04-01

Sequestered mass in low permeability zones has been increasingly recognized as an important source of organic chemical contamination that acts to sustain downgradient plume concentrations above regulated levels. However, few modeling studies have investigated the influence of this sequestered mass and associated (coupled) mass transfer processes on plume persistence in complex dense nonaqueous phase liquid (DNAPL) source zones. This paper employs a multiphase flow and transport simulator (a modified version of the modular transport simulator MT3DMS) to explore the two- and three-dimensional evolution of source zone mass distribution and near-source plume persistence for two ensembles of highly heterogeneous DNAPL source zone realizations. Simulations reveal the strong influence of subsurface heterogeneity on the complexity of DNAPL and sequestered (immobile/sorbed) mass distribution. Small zones of entrapped DNAPL are shown to serve as a persistent source of low concentration plumes, difficult to distinguish from other (sorbed and immobile dissolved) sequestered mass sources. Results suggest that the presence of DNAPL tends to control plume longevity in the near-source area; for the examined scenarios, a substantial fraction (43.3-99.2%) of plume life was sustained by DNAPL dissolution processes. The presence of sorptive media and the extent of sorption non-ideality are shown to greatly affect predictions of near-source plume persistence following DNAPL depletion, with plume persistence varying one to two orders of magnitude with the selected sorption model. Results demonstrate the importance of sorption-controlled back diffusion from low permeability zones and reveal the importance of selecting the appropriate sorption model for accurate prediction of plume longevity. Large discrepancies for both DNAPL depletion time and plume longevity were observed between 2-D and 3-D model simulations. Differences between 2- and 3-D predictions increased in the presence of

Development of methods for remediation of artificial polluted soils and improvement of soils for ecologically clean agricultural production systems

International Nuclear Information System (INIS)

Bogachev, V.; Adrianova, G.; Zaitzev, V.; Kalinin, V.; Kovalenko, E.; Makeev, A.; Malikova, L.; Popov, Yu.; Savenkov, A.; Shnyakina, V.

1996-01-01

The purpose of the research: Development of methods for the remediation of artificial polluted soils and the improvement of polluted lands to ecologically clean agricultural production.The following tasks will be implemented in this project to achieve viable practical solutions: - To determine the priority pollutants, their ecological pathways, and sources of origin. - To form a supervised environmental monitoring data bank throughout the various geo system conditions. - To evaluate the degree of the bio geo system pollution and the influence on the health of the local human populations. - To establish agricultural plant tolerance levels to the priority pollutants. - To calculate the standard concentrations of the priority pollutants for main agricultural plant groups. - To develop a soil remediation methodology incorporating the structural, functional geo system features. - To establish a territory zone division methodology in consideration of the degree of component pollution, plant tolerance to pollutants, plant production conditions, and human health. - Scientific grounding of the soil remediation proposals and agricultural plant material introductions with soil pollution levels and relative plant tolerances to pollutants. Technological Means, Methods, and Approaches Final proposed solutions will be based upon geo system and ecosystem approaches and methodologies. The complex ecological valuation methods of the polluted territories will be used in this investigation. Also, laboratory culture in vitro, application work, and multi-factor field experiments will be conducted. The results will be statistically analyzed using appropriate methods. Expected Results Complex biogeochemical artificial province assessment according to primary pollutant concentrations. Development of agricultural plant tolerance levels relative to the priority pollutants. Assessment of newly introduced plant materials that may possess variable levels of pollution tolerance. Remediation

Definition of a critical confining zone using surface geophysical methods

International Nuclear Information System (INIS)

Eddy-Dilek, C.A.; Hoekstra, P.; Harthill, N.; Blohm, M.; Phillips, D.R.

1996-01-01

Definition of the hydrogeologic framework in layered sediments of fluvial and deltaic origin is a difficult challenge for environmental characterization and remediation programs due to the lithologic and stratigraphic heterogeneities inherent in these settings. These heterogeneties often control contaminant transport and the effectiveness of remediation alternatives, Surface geophysical surveys can be cost-effective methods for characterization, but individual methods have inherent limitations in resolution and sensitivity. A synergistic approach, utilizing two geophysical survey methods was applied, to define and examine the nature and extent of a deep confining zone of regulatory importance, the Crouch Branch Confining Unit, in Coastal Plain sediments at the Savannah River Site. TDEM accurately maps the overall conductance (product of thickness and electrical conductivity) of a confining zone clay facies; from variation in conductance, changes in lithology of the conforming zone can be inferred. Shear wave seismic reflection surveys map the depth to the clay layers, and the clay layer thickness, but provides little information on the lithologic nature of the confining zone. Integrated interpretation of the combined data set (including all available borehole logs) allows for delineation of the lateral and vertical extent of clay-dominated zones, sand-dominated zones, key stratigraphic horizons, and erosional features associated with unconformities. This approach has resulted in the collection of critical information that will be used to optimize remedial system design, representing a significant cost savings to environmental restoration programs at the Savannah River Site

Heavy Metals in Contaminated Soils: A Review of Sources, Chemistry, Risks and Best Available Strategies for Remediation

OpenAIRE

Wuana, Raymond A.; Okieimen, Felix E.

2011-01-01

Scattered literature is harnessed to critically review the possible sources, chemistry, potential biohazards and best available remedial strategies for a number of heavy metals (lead, chromium, arsenic, zinc, cadmium, copper, mercury and nickel) commonly found in contaminated soils. The principles, advantages and disadvantages of immobilization, soil washing and phytoremediation techniques which are frequently listed among the best demonstrated available technologies for cleaning up heavy met...

Attenuation of mining-derived pollutants in the hyporheic zone. A review

International Nuclear Information System (INIS)

Gandy, C.J.; Jarvis, A.P.; Smith, J.W.N.

2007-01-01

Mine water pollution is a major cause of surface- and groundwater pollution in former mining districts throughout Europe. It is a potential barrier to achieving good status water bodies, which is a requirement of the EU Water Framework Directive. In the UK, a concerted effort has been made over the last decade or so to address the scientific and practical challenges relating to the remediation of mine water pollution. However, most of this work has focused on remediation of point sources of pollution (typically arising from abandoned mines and shafts), while the behaviour of mine water at the groundwater-surface water interface (the 'hyporheic zone') has received far less attention in relevant scientific and engineering literature. The extent of mine water pollution and capacity for its attenuation at the hyporheic zone has not been well quantified while, furthermore, the complex chemical and microbial processes occurring there (specifically with reference to mining-derived pollutants) have not been investigated in any depth. The absence of such data may relate, in a large part, to the difficulty in physically measuring volumes and concentrations associated with these river inputs/exports. A far greater body of literature addresses biogeochemical processes at the hyporheic zone (especially relating to manganese), albeit many such articles relate to aqueous metal dynamics in general, rather than mine water specifically. This paper presents a review of the natural attenuation processes that may limit the movement and availability of mining-derived pollutants at the groundwater-surface water (GW-SW) interface, and specifically within the hyporheic zone. A substantial part focuses on precipitation and adsorption processes at the hyporheic zone, as well as discussing the role of microbial processes in governing metal ion mobility. (author)

Attenuation of mining-derived pollutants in the hyporheic zone. A review

Energy Technology Data Exchange (ETDEWEB)

Gandy, C.J.; Jarvis, A.P. [Hydrogeochemical Engineering Research and Outreach (HERO), Institute for Research on Environment and Sustainability, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom); Smith, J.W.N. [Environment Agency, Science Group, Solihull, West Midlands, B92 7HX (United Kingdom); Catchment Science Centre, Sheffield University, Kroto Research Institute, Sheffield, S3 7HQ (United Kingdom)

2007-02-15

Mine water pollution is a major cause of surface- and groundwater pollution in former mining districts throughout Europe. It is a potential barrier to achieving good status water bodies, which is a requirement of the EU Water Framework Directive. In the UK, a concerted effort has been made over the last decade or so to address the scientific and practical challenges relating to the remediation of mine water pollution. However, most of this work has focused on remediation of point sources of pollution (typically arising from abandoned mines and shafts), while the behaviour of mine water at the groundwater-surface water interface (the 'hyporheic zone') has received far less attention in relevant scientific and engineering literature. The extent of mine water pollution and capacity for its attenuation at the hyporheic zone has not been well quantified while, furthermore, the complex chemical and microbial processes occurring there (specifically with reference to mining-derived pollutants) have not been investigated in any depth. The absence of such data may relate, in a large part, to the difficulty in physically measuring volumes and concentrations associated with these river inputs/exports. A far greater body of literature addresses biogeochemical processes at the hyporheic zone (especially relating to manganese), albeit many such articles relate to aqueous metal dynamics in general, rather than mine water specifically. This paper presents a review of the natural attenuation processes that may limit the movement and availability of mining-derived pollutants at the groundwater-surface water (GW-SW) interface, and specifically within the hyporheic zone. A substantial part focuses on precipitation and adsorption processes at the hyporheic zone, as well as discussing the role of microbial processes in governing metal ion mobility. (author)

Obsidian sources of the Coromandel Volcanic Zone, nortthern New Zealand

International Nuclear Information System (INIS)

Moore, P.R.

2013-01-01

The Coromandel Volcanic Zone includes nine geographically discrete obsidian sources (Fanal, Awana, Te Ahumata, Cooks Beach, Hahei, Tairua, Whangamata, Maratoto and Waihi). Each has a distinctive chemical composition, and some can also be differentiated on the basis of visual characteristics of the obsidian. Chemically, the three northern sources (Fanal, Awana, Te Ahumata), constituting the 'Great Barrier Group', are distinguished by high Rb concentrations and a high Rb/Sr ratio. Obsidian from six of the sources is known to have been utilized by pre-European Maori for the manufacture of flake tools, but at present there is no evidence for exploitation of the Awana, Maratoto and Tairua deposits. (author). 54 refs., 5 figs., 2 tabs.

Is rhizosphere remediation sufficient for sustainable revegetation of mine tailings?

Science.gov (United States)

Huang, Longbin; Baumgartl, Thomas; Mulligan, David

2012-01-01

Background Revegetation of mine tailings (fine-grained waste material) starts with the reconstruction of root zones, consisting of a rhizosphere horizon (mostly topsoil and/or amended tailings) and the support horizon beneath (i.e. equivalent to subsoil – mostly tailings), which must be physically and hydro-geochemically stable. This review aims to discuss key processes involved in the development of functional root zones within the context of direct revegetation of tailings and introduces a conceptual process of rehabilitating structure and function in the root zones based on a state transition model. Scope Field studies on the revegetation of tailings (from processing base metal ore and bauxite residues) are reviewed. Particular focus is given to tailings' properties that limit remediation effectiveness. Aspects of root zone reconstruction and vegetation responses are also discussed. Conclusions When reconstructing a root zone system, it is critical to restore physical structure and hydraulic functions across the whole root zone system. Only effective and holistically restored systems can control hydro-geochemical mobility of acutely and chronically toxic factors from the underlying horizon and maintain hydro-geochemical stability in the rhizosphere. Thereafter, soil biological capacity and ecological linkages (i.e. carbon and nutrient cycling) may be rehabilitated to integrate the root zones with revegetated plant communities into sustainable plant ecosystems. A conceptual framework of system transitions between the critical states of root zone development has been proposed. This will illustrate the rehabilitation process in root zone reconstruction and development for direct revegetation with sustainable plant communities. Sustainable phytostabilization of tailings requires the systematic consideration of hydro-geochemical interactions between the rhizosphere and the underlying supporting horizon. It further requires effective remediation strategies to

Is rhizosphere remediation sufficient for sustainable revegetation of mine tailings?

Science.gov (United States)

Huang, Longbin; Baumgartl, Thomas; Mulligan, David

2012-07-01

Revegetation of mine tailings (fine-grained waste material) starts with the reconstruction of root zones, consisting of a rhizosphere horizon (mostly topsoil and/or amended tailings) and the support horizon beneath (i.e. equivalent to subsoil - mostly tailings), which must be physically and hydro-geochemically stable. This review aims to discuss key processes involved in the development of functional root zones within the context of direct revegetation of tailings and introduces a conceptual process of rehabilitating structure and function in the root zones based on a state transition model. Field studies on the revegetation of tailings (from processing base metal ore and bauxite residues) are reviewed. Particular focus is given to tailings' properties that limit remediation effectiveness. Aspects of root zone reconstruction and vegetation responses are also discussed. When reconstructing a root zone system, it is critical to restore physical structure and hydraulic functions across the whole root zone system. Only effective and holistically restored systems can control hydro-geochemical mobility of acutely and chronically toxic factors from the underlying horizon and maintain hydro-geochemical stability in the rhizosphere. Thereafter, soil biological capacity and ecological linkages (i.e. carbon and nutrient cycling) may be rehabilitated to integrate the root zones with revegetated plant communities into sustainable plant ecosystems. A conceptual framework of system transitions between the critical states of root zone development has been proposed. This will illustrate the rehabilitation process in root zone reconstruction and development for direct revegetation with sustainable plant communities. Sustainable phytostabilization of tailings requires the systematic consideration of hydro-geochemical interactions between the rhizosphere and the underlying supporting horizon. It further requires effective remediation strategies to develop hydro-geochemically stable

Remediation of sites with dispersed radioactive contamination

International Nuclear Information System (INIS)

2004-01-01

disciplines, including the health sciences, chemistry, physics, geology, microbiology and environmental engineering, is necessary in order to develop technical solutions. It is also necessary to include information on the political, social and economic context. This report describes remediation techniques that are applicable to dispersed radioactive contamination at a variety of sites, including surface soil, the vadose zone, surface water, sediments and groundwater

In situ remediation of DNAPL compounds in low permeability media fate/transport, in situ control technologies, and risk reduction

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-08-01

In this project, in situ remediation technologies are being tested and evaluated for both source control and mass removal of dense, non-aqueous phase liquid (DNAPL) compounds in low permeability media (LPM). This effort is focused on chlorinated solvents (e.g., trichloroethylene and perchloroethylene) in the vadose and saturated zones of low permeability, massive deposits, and stratified deposits with inter-bedded clay lenses. The project includes technology evaluation and screening analyses and field-scale testing at both clean and contaminated sites in the US and Canada. Throughout this project, activities have been directed at understanding the processes that influence DNPAL compound migration and treatment in LPM and to assessing the operation and performance of the remediation technologies developed and tested. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

Spatial distribution and source apportionment of water pollution in different administrative zones of Wen-Rui-Tang (WRT) river watershed, China.

Science.gov (United States)

Yang, Liping; Mei, Kun; Liu, Xingmei; Wu, Laosheng; Zhang, Minghua; Xu, Jianming; Wang, Fan

2013-08-01

Water quality degradation in river systems has caused great concerns all over the world. Identifying the spatial distribution and sources of water pollutants is the very first step for efficient water quality management. A set of water samples collected bimonthly at 12 monitoring sites in 2009 and 2010 were analyzed to determine the spatial distribution of critical parameters and to apportion the sources of pollutants in Wen-Rui-Tang (WRT) river watershed, near the East China Sea. The 12 monitoring sites were divided into three administrative zones of urban, suburban, and rural zones considering differences in land use and population density. Multivariate statistical methods [one-way analysis of variance, principal component analysis (PCA), and absolute principal component score-multiple linear regression (APCS-MLR) methods] were used to investigate the spatial distribution of water quality and to apportion the pollution sources. Results showed that most water quality parameters had no significant difference between the urban and suburban zones, whereas these two zones showed worse water quality than the rural zone. Based on PCA and APCS-MLR analysis, urban domestic sewage and commercial/service pollution, suburban domestic sewage along with fluorine point source pollution, and agricultural nonpoint source pollution with rural domestic sewage pollution were identified to the main pollution sources in urban, suburban, and rural zones, respectively. Understanding the water pollution characteristics of different administrative zones could put insights into effective water management policy-making especially in the area across various administrative zones.

Rebound of a coal tar creosote plume following partial source zone treatment with permanganate.

Science.gov (United States)

Thomson, N R; Fraser, M J; Lamarche, C; Barker, J F; Forsey, S P

2008-11-14

The long-term management of dissolved plumes originating from a coal tar creosote source is a technical challenge. For some sites stabilization of the source may be the best practical solution to decrease the contaminant mass loading to the plume and associated off-site migration. At the bench-scale, the deposition of manganese oxides, a permanganate reaction byproduct, has been shown to cause pore plugging and the formation of a manganese oxide layer adjacent to the non-aqueous phase liquid creosote which reduces post-treatment mass transfer and hence mass loading from the source. The objective of this study was to investigate the potential of partial permanganate treatment to reduce the ability of a coal tar creosote source zone to generate a multi-component plume at the pilot-scale over both the short-term (weeks to months) and the long-term (years) at a site where there is >10 years of comprehensive synoptic plume baseline data available. A series of preliminary bench-scale experiments were conducted to support this pilot-scale investigation. The results from the bench-scale experiments indicated that if sufficient mass removal of the reactive compounds is achieved then the effective solubility, aqueous concentration and rate of mass removal of the more abundant non-reactive coal tar creosote compounds such as biphenyl and dibenzofuran can be increased. Manganese oxide formation and deposition caused an order-of-magnitude decrease in hydraulic conductivity. Approximately 125 kg of permanganate were delivered into the pilot-scale source zone over 35 days, and based on mass balance estimates 35% reduction for all monitored compounds except for biphenyl, dibenzofuran and fluoranthene 150 days after treatment, which is consistent with the bench-scale experimental results. Pre- and post-treatment soil core data indicated a highly variable and random spatial distribution of mass within the source zone and provided no insight into the mass removed of any of the

Conceptual Models for Migration of Key Groundwater Contaminants Through the Vadose Zone and Into the Upper Unconfined Aquifer Below the B-Complex

Energy Technology Data Exchange (ETDEWEB)

Serne, R. Jeffrey; Bjornstad, Bruce N.; Keller, Jason M.; Thorne, Paul D.; Lanigan, David C.; Christensen, J. N.; Thomas, Gregory S.

2010-07-01

The B-Complex contains 3 major crib and trench disposal sites and 3 SST farms that have released nearly 346 mega-liters of waste liquids containing the following high groundwater risk drivers: ~14,000 kg of CN, 29,000 kg of Cr, 12,000 kg of U and 145 Ci of Tc-99. After a thorough review of available vadose zone sediment and pore water, groundwater plume, field gamma logging, field electrical resistivity studies, we developed conceptual models for which facilities have been the significant sources of the contaminants in the groundwater and estimated the masses of these contaminants remaining in the vadose zone and currently present in the groundwater in comparison to the totals released. This allowed us to make mass balance calculations on how consistent our knowledge is on the current deep vadose zone and groundwater distribution of contaminants. Strengths and weaknesses of the conceptual models are discussed as well as implications on future groundwater and deep vadose zone remediation alternatives. Our hypothesized conceptual models attribute the source of all of the cyanide and most of the Tc-99 currently in the groundwater to the BY cribs. The source of the uranium is the BX-102 tank overfill event and the source of most of the chromium is the B-7-A&B and B-8 cribs. Our mass balance estimates suggest that there are much larger masses of U, CN, and Tc remaining in the deep vadose zone within ~20 ft of the water table than is currently in the groundwater plumes below the B-Complex. This hypothesis needs to be carefully considered before future remediation efforts are chosen. The masses of these groundwater risk drivers in the the groundwater plumes have been increasing over the last decade and the groundwater plumes are migrating to the northwest towards the Gable Gap. The groundwater flow rate appears to flucuate in response to seasonal changes in hydraulic gradient. The flux of contaminants out of the deep vadose zone from the three proposed sources also

Explanation of Significant Differences for the Record of Decision for Interim Actions in Zone 1, East Tennessee Technology Park, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

Bechtel Jacobs

2011-02-01

1945 until 1985. Uranium production was terminated in 1987. ORR was placed on the National Priorities List in 1989, so remediation activities are conducted under CERCLA. The primary contaminants of concern at ETTP follow: (1) In groundwater - volatile organic compounds (VOCs) at multiple locations (trichloroethene is generally the most prevalent compound); (2) In sediment - inorganic elements, radionuclides, and polychlorinated biphenyls; (3) In soil - inorganic elements, radionuclides, semivolatile organic compounds (particularly the polycyclic aromatic hydrocarbons), and VOCs; and (4) In facilities - radionuclides and polychlorinated biphenyls (abandoned facilities also pose a safety and health hazard to workers.) The purposes of the remedial actions selected in the Zone 1 Interim ROD are to allow unrestricted industrial use down to 10 feet and to remediate potential sources of groundwater contamination. Following is a summary of the major components of the Zone 1 Interim ROD remedy: (1) Excavation of the Blair Quarry burial area and associated contaminated soil; (2) Excavation of miscellaneous contaminated soil in the K-895 Cylinder Destruct Facility area and in the Powerhouse Area; (3) Removal of sludge and demolition of the K-710 sludge beds and Imhoff tanks; (4) Implementation of land use controls (LUCs); and (5) Characterization of soil and remediation of areas that exceed remediation levels.

Sources of Magmatic Volatiles Discharging from Subduction Zone Volcanoes

Science.gov (United States)

Fischer, T.

2001-05-01

Subduction zones are locations of extensive element transfer from the Earth's mantle to the atmosphere and hydrosphere. This element transfer is significant because it can, in some fashion, instigate melt production in the mantle wedge. Aqueous fluids are thought to be the major agent of element transfer during the subduction zone process. Volatile discharges from passively degassing subduction zone volcanoes should in principle, provide some information on the ultimate source of magmatic volatiles in terms of the mantle, the crust and the subducting slab. The overall flux of volatiles from degassing volcanoes should be balanced by the amount of volatiles released from the mantle wedge, the slab and the crust. Kudryavy Volcano, Kurile Islands, has been passively degassing at 900C fumarole temperatures for at least 40 years. Extensive gas sampling at this basaltic andesite cone and application of CO2/3He, N2/3He systematics in combination with C and N- isotopes indicates that 80% of the CO2 and approximately 60% of the N 2 are contributed from a sedimentary source. The mantle wedge contribution for both volatiles is, with 12% and 17% less significant. Direct volatile flux measurements from the volcano using the COSPEC technique in combination with direct gas sampling allows for the calculation of the 3He flux from the volcano. Since 3He is mainly released from the astenospheric mantle, the amount of mantle supplying the 3He flux can be determined if initial He concentrations of the mantle melts are known. The non-mantle flux of CO2 and N2 can be calculated in similar fashion. The amount of non-mantle CO2 and N2 discharging from Kudryavy is balanced by the amount of CO2 and N2 subducted below Kudryavy assuming a zone of melting constrained by the average spacing of the volcanoes along the Kurile arc. The volatile budget for Kudryavy is balanced because the volatile flux from the volcano is relatively small (75 t/day (416 Mmol/a) SO2, 360 Mmol/a of non-mantle CO2 and

Using the natural biodegradation potential of shallow soils for in-situ remediation of deep vadose zone and groundwater.

Science.gov (United States)

Avishai, Lior; Siebner, Hagar; Dahan, Ofer; Ronen, Zeev

2017-02-15

In this study, we examined the ability of top soil to degrade perchlorate from infiltrating polluted groundwater under unsaturated conditions. Column experiments designed to simulate typical remediation operation of daily wetting and draining cycles of contaminated water amended with an electron donor. Covering the infiltration area with bentonite ensured anaerobic conditions. The soil remained unsaturated, and redox potential dropped to less than -200mV. Perchlorate was reduced continuously from ∼1150mg/L at the inlet to ∼300mg/L at the outlet in daily cycles. Removal efficiency was between 60 and 84%. No signs of bioclogging were observed during three operation months although occasional iron reduction observed due to excess electron donor. Changes in perchlorate reducing bacteria numbers were inferred from an increased in pcrA gene abundances from ∼10 5 to 10 7 copied per gram at the end of the experiment indicating the growth of perchlorate-reducing bacteria. We proposed that the topsoil may serve as a bioreactor to treat high concentrations of perchlorate from the contaminated groundwater. The treated water that infiltrates from the topsoil through the vadose zone could be used to flush perchlorate from the deep vadose zone into the groundwater where it is retrieved again for treatment in the topsoil. Copyright © 2016 Elsevier B.V. All rights reserved.

VADOSE ZONE STUDIES AT AN INDUSTRIAL CONTAMINATED SITE: THE VADOSE ZONE MONITORING SYSTEM AND CROSS-HOLE GEOPHYSICS

OpenAIRE

Fernandez de Vera, Natalia; Beaujean, Jean; Jamin, Pierre; Nguyen, Frédéric; Dahan, Ofer; Vanclooster, Marnik; Brouyère, Serge

2014-01-01

In situ vadose zone characterization is essential to improve risk characterization and remediation measures for soil and groundwater contamination. However, most available technologies have been developed in the context of agricultural soils. Most of these methodologies are not applicable at industrial sites, where soils and contamination differ in origin and composition. In addition, they are applicable only in the first meters of soils, leaving deeper vadose zones with lack of informatio...

Hanford Sitewide Groundwater Remediation Strategy

International Nuclear Information System (INIS)

Knepp, A.J.; Isaacs, J.D.

1997-09-01

This document fulfills the requirements of the Hanford Federal Facility Agreement and Consent Order, Milestone M-13-81, to develop a concise statement of strategy that describe show the Hanford Site groundwater remediation will be accomplished. The strategy addresses objectives and goals, prioritization of activities, and technical approaches for groundwater cleanup. The strategy establishes that the overall goal of groundwater remediation on the Hanford Site is to restore groundwater to its beneficial uses in terms of protecting human health and the environment, and its use as a natural resource. The Hanford Future Site Uses Working Group established two categories for groundwater commensurate with various proposed landuses: (1) restricted use or access to groundwater in the Central Plateau and in a buffer zone surrounding it and (2) unrestricted use or access to groundwater for all other areas. In recognition of the Hanford Future Site Uses Working Group and public values, the strategy establishes that the sitewide approach to groundwater cleanup is to remediate the major plumes found in the reactor areas that enter the Columbia River and to contain the spread and reduce the mass of the major plumes found in the Central Plateau

Responses of wild small mammals to arsenic pollution at a partially remediated mining site in Southern France.

Science.gov (United States)

Drouhot, Séverine; Raoul, Francis; Crini, Nadia; Tougard, Christelle; Prudent, Anne-Sophie; Druart, Coline; Rieffel, Dominique; Lambert, Jean-Claude; Tête, Nicolas; Giraudoux, Patrick; Scheifler, Renaud

2014-02-01

Partial remediation actions at a former gold mine in Southern France led to a mosaic of contaminated and rehabilitated zones. In this study, the distribution of arsenic and its potential adverse effects on small mammals were investigated. The effectiveness of remediation for reducing the transfer of this element into wildlife was also discussed. Arsenic levels were measured in the soil and in the stomach contents, livers, kidneys, and lungs of four small mammal species (the wood mouse (Apodemus sylvaticus), the Algerian mouse (Mus spretus), the common vole (Microtus arvalis), and the greater white-toothed shrew (Crocidura russula)). The animals were caught at the former extraction site, in zones with three different levels of remediation treatments, and at a control site. Arsenic concentrations in the soil were highly spatially heterogeneous (ranging from 29 to 18,900 μg g(-1)). Despite the decrease in arsenic concentrations in the remediated soils, both wood mice and Algerian mice experienced higher oral exposure to arsenic in remediated zones than in the control area. The accumulated arsenic in their organs showed higher intra-zonal variability than the arsenic distribution in the soil, suggesting that, in addition to remediation processes, other variables can help explain arsenic transfer to wildlife, such as the habitat and diet preferences of the animals or their mobility. A weak but significant correlation between arsenic concentration and body condition was observed, and weak relationships between the liver/kidney/lung mass and arsenic levels were also detected, suggesting possible histological alterations. © 2013.

Passive remediation strategies for petroleum contaminated sites

International Nuclear Information System (INIS)

Everett, L.G.; Cullen, S.J.; Eccles, L.A.

1991-01-01

The US EPA is becoming increasingly aware of costs and the limited success of existing remediation strategies. Research teams within the US EPA believe that if passive remediation can be successfully demonstrated, it is a candidate for best available technology. Passive remediation, however, must be demonstrated through the use of monitoring techniques, which demonstrate: contaminants are not moving in the dissolved, adsorbed or free product phase; and contamination is biodegrading in-place. This paper presents a concise monitoring and analysis strategy for passive remediation. Specifically, the paper presents the accuracy, precision and operating range of neutron moderation techniques as a low cost, real-time screening tool to measure the migration of the dissolved phase in soil moisture, the stabilized adsorbed phase and free product movement. In addition, the paper identifies the capillary pressure range through which the dissolved phase will move and identifies techniques for satisfying the risk analysis that movement is not taking place. The rationale for passive remediation taking place is confirmed through a discussion of gas ratios associated with bacterial assimilation of hydrocarbons. Gas ratios which are relatively constant above ground are highly inverted in the subsurface at contamination sites. The use of frequent screening of a vertical geologic profile using least cost techniques and the infrequent analysis of soil gas ratios provides the required data upon which the public will accept passive remediation as best available technology at a particular site. The paper points out that neutron moderation is a high candidate vadose zone monitoring device and identifies alternative techniques using resistivity and dielectric constants, which are in the developmental stage. The economic implications for passive remediation are enormous relative to the excavation and remediation strategies which are currently in use

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

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

Remediation plans in family medicine residency

Science.gov (United States)

Audétat, Marie-Claude; Voirol, Christian; Béland, Normand; Fernandez, Nicolas; Sanche, Gilbert

2015-01-01

Abstract Objective To assess use of the remediation instrument that has been implemented in training sites at the University of Montreal in Quebec to support faculty in diagnosing and remediating resident academic difficulties, to examine whether and how this particular remediation instrument improves the remediation process, and to determine its effects on the residents’ subsequent rotation assessments. Design A multimethods approach in which data were collected from different sources: remediation plans developed by faculty, program statistics for the corresponding academic years, and students’ academic records and rotation assessment results. Setting Family medicine residency program at the University of Montreal. Participants Family medicine residents in academic difficulty. Main outcome measures Assessment of the content, process, and quality of remediation plans, and students’ academic and rotation assessment results (successful, below expectations, or failure) both before and after the remediation period. Results The framework that was developed for assessing remediation plans was used to analyze 23 plans produced by 10 teaching sites for 21 residents. All plans documented cognitive problems and implemented numerous remediation measures. Although only 48% of the plans were of good quality, implementation of a remediation plan was positively associated with the resident’s success in rotations following the remediation period. Conclusion The use of remediation plans is well embedded in training sites at the University of Montreal. The residents’ difficulties were mainly cognitive in nature, but this generally related to deficits in clinical reasoning rather than knowledge gaps. The reflection and analysis required to produce a remediation plan helps to correct many academic difficulties and normalize the academic career of most residents in difficulty. Further effort is still needed to improve the quality of plans and to support teachers.

Assessing the joint impact of DNAPL source-zone behavior and degradation products on the probabilistic characterization of human health risk

Science.gov (United States)

Henri, Christopher V.; Fernàndez-Garcia, Daniel; de Barros, Felipe P. J.

2016-02-01

The release of industrial contaminants into the subsurface has led to a rapid degradation of groundwater resources. Contamination caused by Dense Non-Aqueous Phase Liquids (DNAPLs) is particularly severe owing to their limited solubility, slow dissolution and in many cases high toxicity. A greater insight into how the DNAPL source zone behavior and the contaminant release towards the aquifer impact human health risk is crucial for an appropriate risk management. Risk analysis is further complicated by the uncertainty in aquifer properties and contaminant conditions. This study focuses on the impact of the DNAPL release mode on the human health risk propagation along the aquifer under uncertain conditions. Contaminant concentrations released from the source zone are described using a screening approach with a set of parameters representing several scenarios of DNAPL architecture. The uncertainty in the hydraulic properties is systematically accounted for by high-resolution Monte Carlo simulations. We simulate the release and the transport of the chlorinated solvent perchloroethylene and its carcinogenic degradation products in randomly heterogeneous porous media. The human health risk posed by the chemical mixture of these contaminants is characterized by the low-order statistics and the probability density function of common risk metrics. We show that the zone of high risk (hot spot) is independent of the DNAPL mass release mode, and that the risk amplitude is mostly controlled by heterogeneities and by the source zone architecture. The risk is lower and less uncertain when the source zone is formed mostly by ganglia than by pools. We also illustrate how the source zone efficiency (intensity of the water flux crossing the source zone) affects the risk posed by an exposure to the chemical mixture. Results display that high source zone efficiencies are counter-intuitively beneficial, decreasing the risk because of a reduction in the time available for the production

200 Areas soil remediation strategy -- Environmental Restoration Program

International Nuclear Information System (INIS)

1996-09-01

The remediation and waste management activities in the 200 Areas of the Hanford Site (located in Richland, Washington) currently range from remediating groundwater, remediating source units (contaminated soils), decontaminating and decommissioning of buildings and structures, maintaining facilities, managing transuranic, low-level and mixed waste, and operating tank farms that store high-level waste. This strategy focuses on the assessment and remediation of soil that resulted from the discharge of liquids and solids from processing facilities to the ground (e.g., ponds, ditches, cribs, burial grounds) in the 200 Areas and addresses only those waste sites assigned to the Environmental Restoration Program

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...

Botanical ethnoveterinary therapies used by agro-pastoralists of Fafan zone, Eastern Ethiopia.

Science.gov (United States)

Feyera, Teka; Mekonnen, Endalkachew; Wakayo, Befekadu Urga; Assefa, Solomon

2017-08-09

In Ethiopia, plant based remedies are still the most important and sometimes the only source of therapeutics in the management of livestock diseases. However, documentation of this indigenous knowledge of therapeutic system still remains at a minimum level. The aim of this study was, thus, to document the traditional knowledge of botanical ethnoveterinary therapies in the agro-pastoral communities of Fafan Zone, Eastern Ethiopia. The study employed a cross-sectional participatory survey. Purposive sampling technique was applied to select key respondents with desired knowledge in traditional animal health care system. Data were gathered from a total of 24 (22 males and 2 females) ethnoveterinary practitioners and herbalists using an in-depth-interview complemented with group discussion and field observation. The current ethnobotanical survey indicated that botanical ethnoveterinary therapies are the mainstay of livestock health care system in the studied communities. A total of 49 medicinal plants belonging to 21 families, which are used by traditional healers and livestock raisers for the treatment of 29 types of livestock ailments/health problems, were identified in the study area. The major plant parts used were leaves (43%) followed by roots (35%). In most cases, traditional plant remedies were prepared by pounding the remedial plant part and mixing it with water at room temperature. The various types of identified medicinal plants and their application in ethnoveternary practice of Fafan zone agro pastoralists indicate the depth of indigenous knowledge in ethnobotanical therapy. The identified medicinal plants could be potentially useful for future phytochemical and pharmacological studies.

Flux and Mass Reduction Resulting from ZVIClay Remediation of a PCE DNAPL Source Zone

DEFF Research Database (Denmark)

Fjordbøge, Annika Sidelmann; Kjeldsen, Peter; Riis, C.

2010-01-01

of bentonite clay. The degradation of PCE in the treated source area and the development in the downstream flux of chlorinated compounds have been monitored in six sampling campaigns. A PCE half-life of 50 days and a reduction of the average concentration of PCE of more than 99% were found during the first...

The Oak Ridge Field Research Center : Advancing Scientific Understanding of the Transportation, Fate, and Remediation of Subsurface Contamination Sources and Plumes

International Nuclear Information System (INIS)

David Watson

2005-01-01

Historical research, development, and testing of nuclear materials across this country resulted in subsurface contamination that has been identified at over 7,000 discrete sites across the U.S. Department of Energy (DOE) complex. With the end of the Cold War threat, DOE has shifted its emphasis to remediation, decommissioning, and decontamination of the immense volumes of contaminated groundwater, sediments, and structures at its sites. DOE currently is responsible for remediating 1.7 trillion gallons of contaminated groundwater, an amount equal to approximately four times the daily U.S. water consumption, and 40 million cubic meters of contaminated soil, enough to fill approximately 17 professional sports stadiums.* DOE also sponsors research intended to improve or develop remediation technologies, especially for difficult, currently intractable contaminants or conditions. The Oak Ridge FRC is representative of some difficult sites, contaminants, and conditions. Buried wastes in contact with a shallow water table have created huge reservoirs of contamination. Rainfall patterns affect the water table level seasonally and over time. Further, the hydrogeology of the area, with its fractures and karst geology, affects the movement of contaminant plumes. Plumes have migrated long distances and to surface discharge points through ill-defined preferred flowpaths created by the fractures and karst conditions. From the standpoint of technical effectiveness, remediation options are limited, especially for contaminated groundwater. Moreover, current remediation practices for the source areas, such as capping, can affect coupled processes that, in turn, may affect the movement of subsurface contaminants in unknown ways. Research conducted at the FRC or with FRC samples therefore promotes understanding of the processes that influence the transport and fate of subsurface contaminants, the effectiveness and long-term consequences of extant remediation options, and the

The application of in situ air sparging as an innovative soils and ground water remediation technology

International Nuclear Information System (INIS)

Marley, M.C.; Hazebrouck, D.J.; Walsh, M.T.

1992-01-01

Vapor extraction (soil venting) has been demonstrated to be a successful and cost-effective remediation technology for removing VOCs from the vadose (unsaturated) zone. However, in many cases, seasonal water table fluctuations, drawdown associated with pump-and-treat remediation techniques, and spills involving dense, non-aqueous phase liquids (DNAPLS) create contaminated soil below the water table. Vapor extraction alone is not considered to be an optimal remediation technology to address this type of contamination. An innovative approach to saturated zone remediation is the use of sparging (injection) wells to inject a hydrocarbon-free gaseous medium (typically air) into the saturated zone below the areas of contamination. The contaminants dissolved in the ground water and sorbed onto soil particles partition into the advective air phase, effectively simulating an in situ air-stripping system. The stripped contaminants are transported in the gas phase to the vadose zone, within the radius of influence of a vapor extraction and vapor treatment system. In situ air sparging is a complex multifluid phase process, which has been applied successfully in Europe since the mid-1980s. To date, site-specific pilot tests have been used to design air-sparging systems. Research is currently underway to develop better engineering design methodologies for the process. Major design parameters to be considered include contaminant type, gas injection pressures and flow rates, site geology, bubble size, injection interval (areal and vertical) and the equipment specifications. Correct design and operation of this technology has been demonstrated to achieve ground water cleanup of VOC contamination to low part-per-billion levels

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.

A framework for sourcing of evaporation between saturated and unsaturated zone in bare soil condition

NARCIS (Netherlands)

Balugani, E.; Lubczynski, M.; Metselaar, K.A.

2016-01-01

Sourcing subsurface evaporation (Ess) into groundwater (Eg) and unsaturated zone (Eu) components has received little scientific attention so far, despite its importance in water management and agriculture. We propose a novel sourcing framework, with its implementation in dedicated post-processing

Barometric pumping with a twist: VOC containment and remediation without boreholes. Phase I

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-08-01

The majority of the planned remediation sites within the DOE complex are contaminated with volatile organic compounds (VOCs). In many instances the contamination has not reached the water table, does not pose an immediate threat, and is not considered a high priority problem. These sites will ultimately require remediation of some type, either by active vapor extraction, bioremediation, or excavation and ex-situ soil treatment. The cost of remediating these sites can range from $50 K to more than $150 K, depending on site characteristics, contaminants, and remediation method. Additionally, for many remediated sites, residual contamination exists which could not practically be removed by the applied remediation technology. These circumstances result in modest sites with contamination of limited risk, but by regulation they must still be controlled. A remediation solution being developed by Science and Engineering Associates, Inc. (SEA) for the Department of Energy serves as an in-situ containment and extraction methodology for sites where most or all of the contamination resides in the vadose zone soil. The approach capitalizes on the advective soil gas movement resulting from barometric pressure oscillations.

GEOCHEMISTRY OF SUBSURFACE REACTIVE BARRIERS FOR REMEDIATION OF CONTAMINATED GROUND WATER

Science.gov (United States)

Reactive barriers that couple subsurface fluid flow with a passive chemical treatment zone are emerging, cost effective approaches for in-situ remediation of contaminated groundwater. Factors such as the build-up of surface precipitates, bio-fouling, and changes in subsurface tr...

Adapting Advances in Remediation Science to Long-Term Surveillance

International Nuclear Information System (INIS)

Peterson, D.M.

2006-01-01

Several facets of groundwater remediation stand to gain from the advances made during recent years in disciplines that contribute to remediation science. Engineered remedies designed to aggressively remove subsurface contamination should benefit from this progress, and more passive cleanup methods and the long-term monitoring of such passive approaches may benefit equally well if not more. The U.S. Department of Energy Office of Legacy Management (LM) has adopted a strategic plan that is designed to take advantage of technological improvements in the monitoring and assessment of both active and passive groundwater remedies. Flexible adaptation of new technologies, as they become available, to long-term surveillance at LM sites is expected to reduce site stewardship costs while ensuring the future protection of human health and the environment. Some of the technologies are expected to come from government initiatives that focus on the needs of subsurface monitoring. Additional progress in monitoring science will likely result from continual improvements in our understanding of contaminant fate-and-transport processes in groundwater and the vadose zone. (authors)

Adapting Advances in Remediation Science to Long-Term Surveillance

Energy Technology Data Exchange (ETDEWEB)

Peterson, Dave [S.M. Stoller Corporation

2006-03-01

Several facets of groundwater remediation stand to gain from the advances made during recent years in disciplines that contribute to remediation science. Engineered remedies designed to aggressively remove subsurface contamination should benefit from this progress, and more passive cleanup methods and the long-term monitoring of such passive approaches may benefit equally well if not more. The U.S. Department of Energy Office of Legacy Management (LM) has adopted a strategic plan that is designed to take advantage of technological improvements in the monitoring and assessment of both active and passive groundwater remedies. Flexible adaptation of new technologies, as they become available, to long-term surveillance at LM sites is expected to reduce site stewardship costs while ensuring the future protection of human health and the environment. Some of the technologies are expected to come from government initiatives that focus on the needs of subsurface monitoring. Additional progress in monitoring science will likely result from continual improvements in our understanding of contaminant fate-and-transport processes in the groundwater and the vadose zone.

Deep Vadose Zone Treatability Test of Soil Desiccation for the Hanford Central Plateau: Final Report

Energy Technology Data Exchange (ETDEWEB)

Truex, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chronister, Glen B. [CH2M Hill Plateau Remediation Co., Richland, WA (United States); Strickland, Christopher E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Christian D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tartakovsky, Guzel D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Oostrom, Martinus [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Clayton, Ray E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Timothy C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Freedman, Vicky L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rockhold, Mark L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Greenwood, William J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Peterson, John E. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hubbard, Susan S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ward, Anderson L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2018-02-20

Some of the inorganic and radionuclide contaminants in the deep vadose zone at the Hanford Site are at depths where direct exposure pathways are not of concern, but may need to be remediated to protect groundwater. The Department of Energy developed a treatability test program for technologies to address Tc-99 and uranium in the deep vadose zone. These contaminants are mobile in the subsurface environment, have been detected at high concentrations deep in the vadose zone, and at some locations have reached groundwater. The treatability test of desiccation described herein was conducted as an element of the deep vadose zone treatability test program. Desiccation was shown to be a potentially effective vadose zone remediation technology to protect groundwater when used in conjunction with a surface infiltration barrier.

Cost benefit analysis for remediation of a nuclear industry landfill

International Nuclear Information System (INIS)

Parker, Tom; Hardisty, Paul; Dennis, Frank; Liddiard, Mark; McClelland, Paul

2006-01-01

An old landfill site, licensed to receive inert construction waste, is situated on the top of hard rock cliffs adjacent to the sea at the Dounreay nuclear facility in Scotland. During restoration and investigation work at the landfill, radioactively contaminated material and asbestos was identified. UKAEA subsequently investigated the feasibility of remediating the landfill with the aim of removing any remaining radioactive or otherwise-contaminated material. The cost of landfill remediation would be considerable, making Cost Benefit Analysis (CBA) an ideal tool for assessing remediation options. The overall conclusion of the CBA, from a remedial decision making point of view, is that the remediation objective for the landfill should be to reduce any impacts to the current receptors through a comprehensive pathway control scheme. This would be considerably less expensive than even a limited source removal approach. Aggressive source removal objectives are not likely to be economic, even under the most conservative assumptions. A natural monitored attenuation approach will not be economic. All remediation options are considered assuming compliance with the existing regulatory requirements to monitor and cap the landfill before and after closure

Cost benefit analysis for remediation of a nuclear industry landfill

Energy Technology Data Exchange (ETDEWEB)

Parker, Tom; Hardisty, Paul [WorleyParsons Komex, Bristol (United Kingdom); Dennis, Frank; Liddiard, Mark; McClelland, Paul [UKAEA, Dounreay (United Kingdom)

2006-09-15

An old landfill site, licensed to receive inert construction waste, is situated on the top of hard rock cliffs adjacent to the sea at the Dounreay nuclear facility in Scotland. During restoration and investigation work at the landfill, radioactively contaminated material and asbestos was identified. UKAEA subsequently investigated the feasibility of remediating the landfill with the aim of removing any remaining radioactive or otherwise-contaminated material. The cost of landfill remediation would be considerable, making Cost Benefit Analysis (CBA) an ideal tool for assessing remediation options. The overall conclusion of the CBA, from a remedial decision making point of view, is that the remediation objective for the landfill should be to reduce any impacts to the current receptors through a comprehensive pathway control scheme. This would be considerably less expensive than even a limited source removal approach. Aggressive source removal objectives are not likely to be economic, even under the most conservative assumptions. A natural monitored attenuation approach will not be economic. All remediation options are considered assuming compliance with the existing regulatory requirements to monitor and cap the landfill before and after closure.

Developing a disposal and remediation plan

International Nuclear Information System (INIS)

Messier, T.S.

1999-01-01

The environmental release of wastes generated by the upstream oil and gas industry in Alberta can result in polluted soil and groundwater at several facilities across the province. Responsibility for decommissioning upstream oil and gas facilities falls under the jurisdiction of the Alberta Energy and Utilities Board (EUB) and Alberta Environmental Protection (AEP). This paper outlines a protocol that can serve as a framework for the development of a plan to dispose of oilfield waste and to remediate related contaminated soils. The components involved in developing a disposal and remediation plan for oilfield wastes are: (1) identifying the potential source of pollution and oilfield waste generation, (2) characterizing oilfield wastes, (3) determining the nature and extent of soil and groundwater pollution, (4) preparing a remedial action plan, (5) assessing the viability of various remediation options, and (6) preparing health and safety plan. 12 refs., 2 tabs., 2 figs

A framework for sourcing of evaporation between saturated and unsaturated zone in bare soil condition

NARCIS (Netherlands)

Balugani, E.; Lubczynski, M.W.; Metselaar, Klaas

2016-01-01

Sourcing subsurface evaporation (E_ss) into groundwater (E_g) and unsaturated zone (E_u) components has received little scientific attention so far, despite its importance in water management and agriculture. We propose a novel sourcing framework, with its

Vadose zone characterisation at industrial contaminated sites

OpenAIRE

Fernandez de Vera, Natalia; Dahan, Ofer; Dassargues, Alain; Vanclooster, Marnik; Nguyen, Frédéric; Brouyère, Serge

2015-01-01

In order to improve risk characterization and remediation measures for soil and groundwater contamination, there is a need to improve in situ vadose zone characterization. However, most available technologies have been developed in the context of agricultural soils. Such methodologies are not applicable at industrial sites, where soils and contamination differ in origin and composition. To overcome such difficulties, a vadose zone experiment has been setup at a former industrial site in ...

The ecological-commerce (ECO-COM) zone concept for developing biomass energy from contaminated resources: A new demonstration zone for the Republic of Belarus

International Nuclear Information System (INIS)

McCarn, D.W.; Iakoushev, A.; Grebenkov, A.J.

1996-01-01

Following the Chernobyl Accident, about 17,000 km 2 of forested area in the Gomel Oblask of Belarus was contaminated with radioactive material. Remediation and productive utilization of these resources is proposed through the use of the forest biomass as a source of energy. The energy sector of Belarus requires rapid development of new sources of power generating capacity if projected needs are to be met. The current energy balance in the region of the Contaminated Territories shows a deficit of almost 600 MW which is currently being imported. The next five years will see a significant reduction of the energy production capacity of Belarus due to retirement of a large portion of existing facilities. The World Bank has stressed the importance of biomass energy development in Belarus to reduce reliance on imported sources of energy. This proposal addresses this need. A Non-Profit Corporation (NPC) is proposed to manage all identified resources in the contaminated territories in Belarus for use by a duty-free / tax-free Ecological - Commerce (ECO-COM) Zone. The ECO-COM Zone would produce energy, pulp, paper, and other products directly from radioactively contaminated materials. A board of internationally recognized specialists in radiological safety would insure that these products meet internationally acceptable safety norms. A primary benefit for Belarus would be the creation of significant electrical energy capacity as well as expanded pulp and paper production in addition to the removal of a large fraction of the total radioactive source-term from the contaminated land. A short list of projects is presented at the end of this report that meet basic infrastructural, economic, industrial, and energy savings activities permitting the rapid payback of investments. This list was compiled for ECO-COM and recommended by the Ministry of Energy Savings in the framework of the Energy Efficiency 2000 (EE 2000) Demonstration Zone program adopted for Belarus

Soil contamination with cadmium, consequences and remediation using organic amendments.

Science.gov (United States)

Khan, Muhammad Amjad; Khan, Sardar; Khan, Anwarzeb; Alam, Mehboob

2017-12-01

Cadmium (Cd) contamination of soil and food crops is a ubiquitous environmental problem that has resulted from uncontrolled industrialization, unsustainable urbanization and intensive agricultural practices. Being a toxic element, Cd poses high threats to soil quality, food safety, and human health. Land is the ultimate source of waste disposal and utilization therefore, Cd released from different sources (natural and anthropogenic), eventually reaches soil, and then subsequently bio-accumulates in food crops. The stabilization of Cd in contaminated soil using organic amendments is an environmentally friendly and cost effective technique used for remediation of moderate to high contaminated soil. Globally, substantial amounts of organic waste are generated every day that can be used as a source of nutrients, and also as conditioners to improve soil quality. This review paper focuses on the sources, generation, and use of different organic amendments to remediate Cd contaminated soil, discusses their effects on soil physical and chemical properties, Cd bioavailability, plant uptake, and human health risk. Moreover, it also provides an update of the most relevant findings about the application of organic amendments to remediate Cd contaminated soil and associated mechanisms. Finally, future research needs and directions for the remediation of Cd contaminated soil using organic amendments are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

A survey of ethnoveterinary botanical remedies in Ogun State and ...

African Journals Online (AJOL)

Twenty four villages were visited during a cross sectional survey of ethno veterinary botanical remedies used for the management of animal diseases in four local government areas randomly selected cutting across the four geopolitical zones in Ogun State. A total of 323 households were purposively selected and ...

Assessing TCE source bioremediation by geostatistical analysis of a flux fence.

Science.gov (United States)

Cai, Zuansi; Wilson, Ryan D; Lerner, David N

2012-01-01

Mass discharge across transect planes is increasingly used as a metric for performance assessment of in situ groundwater remediation systems. Mass discharge estimates using concentrations measured in multilevel transects are often made by assuming a uniform flow field, and uncertainty contributions from spatial concentration and flow field variability are often overlooked. We extend our recently developed geostatistical approach to estimate mass discharge using transect data of concentration and hydraulic conductivity, so accounting for the spatial variability of both datasets. The magnitude and uncertainty of mass discharge were quantified by conditional simulation. An important benefit of the approach is that uncertainty is quantified as an integral part of the mass discharge estimate. We use this approach for performance assessment of a bioremediation experiment of a trichloroethene (TCE) source zone. Analyses of dissolved parent and daughter compounds demonstrated that the engineered bioremediation has elevated the degradation rate of TCE, resulting in a two-thirds reduction in the TCE mass discharge from the source zone. The biologically enhanced dissolution of TCE was not significant (~5%), and was less than expected. However, the discharges of the daughter products cis-1,2, dichloroethene (cDCE) and vinyl chloride (VC) increased, probably because of the rapid transformation of TCE from the source zone to the measurement transect. This suggests that enhancing the biodegradation of cDCE and VC will be crucial to successful engineered bioremediation of TCE source zones. © 2012, The Author(s). Ground Water © 2012, National Ground Water Association.

Application of risk management techniques for the remediation of an old mining site in Greece.

Science.gov (United States)

Panagopoulos, I; Karayannis, A; Adam, K; Aravossis, K

2009-05-01

This article summarizes the project and risk management of a remediation/reclamation project in Lavrion, Greece. In Thoricos the disposal of mining and metallurgical wastes in the past resulted in the contamination with heavy metals and acid mine drainage. The objective of this reclamation project was to transform this coastal zone from a contaminated site to an area suitable for recreation purposes. A separate risk assessment study was performed to provide the basis of determining the relevant environmental contamination and to rate the alternative remedial schemes involved. The study used both existing data available from comprehensive studies, as well as newly collected field data. For considering environmental risk, the isolation and minimization of risk option was selected, and a reclamation scheme, based on environmental criteria, was applied which was comprised of in situ neutralization, stabilization and cover of the potentially acid generating wastes and contaminated soils with a low permeability geochemical barrier. Additional measures were specifically applied in the areas where highly sulphidic wastes existed constituting active acid generation sources, which included the encapsulation of wastes in HDPE liners installed on clay layers.

A framework for sourcing of evaporation between saturated and unsaturated zone in bare soil condition

OpenAIRE

Balugani, E.; Lubczynski, M.W.; Metselaar, Klaas

2016-01-01

Sourcing subsurface evaporation (Ess) into groundwater (Eg) and unsaturated zone (Eu) components has received little scientific attention so far, despite its importance in water management and agriculture. We propose a novel sourcing framework, with its implementation in dedicated post-processing software called SOURCE (used along with the HYDRUS1D model), to study evaporation sourcing dynamics, define quantitatively “shallow” and “deep” water table conditions and test the applicability of wa...

Comparisons of Source Characteristics between Recent Inland Crustal Earthquake Sequences inside and outside of Niigata-Kobe Tectonic Zone, Japan

Science.gov (United States)

Somei, K.; Asano, K.; Iwata, T.; Miyakoshi, K.

2012-12-01

After the 1995 Kobe earthquake, many M7-class inland earthquakes occurred in Japan. Some of those events (e.g., the 2004 Chuetsu earthquake) occurred in a tectonic zone which is characterized as a high strain rate zone by the GPS observation (Sagiya et al., 2000) or dense distribution of active faults. That belt-like zone along the coast in Japan Sea side of Tohoku and Chubu districts, and north of Kinki district, is called as the Niigata-Kobe tectonic zone (NKTZ, Sagiya et al, 2000). We investigate seismic scaling relationship for recent inland crustal earthquake sequences in Japan and compare source characteristics between events occurring inside and outside of NKTZ. We used S-wave coda part for estimating source spectra. Source spectral ratio is obtained by S-wave coda spectral ratio between the records of large and small events occurring close to each other from nation-wide strong motion network (K-NET and KiK-net) and broad-band seismic network (F-net) to remove propagation-path and site effects. We carefully examined the commonality of the decay of coda envelopes between event-pair records and modeled the observed spectral ratio by the source spectral ratio function with assuming omega-square source model for large and small events. We estimated the corner frequencies and seismic moment (ratio) from those modeled spectral ratio function. We determined Brune's stress drops of 356 events (Mw: 3.1-6.9) in ten earthquake sequences occurring in NKTZ and six sequences occurring outside of NKTZ. Most of source spectra obey omega-square source spectra. There is no obvious systematic difference between stress drops of events in NKTZ zone and others. We may conclude that the systematic tendency of seismic source scaling of the events occurred inside and outside of NKTZ does not exist and the average source scaling relationship can be effective for inland crustal earthquakes. Acknowledgements: Waveform data were provided from K-NET, KiK-net and F-net operated by

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

Historical hydronuclear testing: Characterization and remediation technologies

Energy Technology Data Exchange (ETDEWEB)

Shaulis, L.; Wilson, G.; Jacobson, R.

1997-09-01

This report examines the most current literature and information available on characterization and remediation technologies that could be used on the Nevada Test Site (NTS) historical hydronuclear test areas. Historical hydronuclear tests use high explosives and a small amount of plutonium. The explosion scatters plutonium within a contained subsurface environment. There is currently a need to characterize these test areas to determine the spatial extent of plutonium in the subsurface and whether geohydrologic processes are transporting the plutonium away from the event site. Three technologies were identified to assist in the characterization of the sites. These technologies are the Pipe Explorer{trademark}, cone penetrometer, and drilling. If the characterization results indicate that remediation is needed, three remediation technologies were identified that should be appropriate, namely: capping or sealing the surface, in situ grouting, and in situ vitrification. Capping the surface would prevent vertical infiltration of water into the soil column, but would not restrict lateral movement of vadose zone water. Both the in situ grouting and vitrification techniques would attempt to immobilize the radioactive contaminants to restrict or prevent leaching of the radioactive contaminants into the groundwater. In situ grouting uses penetrometers or boreholes to inject the soil below the contaminant zone with low permeability grout. In situ vitrification melts the soil containing contaminants into a solid block. This technique would provide a significantly longer contaminant immobilization, but some research and development would be required to re-engineer existing systems for use at deep soil depths. Currently, equipment can only handle shallow depth vitrification. After existing documentation on the historical hydronuclear tests have been reviewed and the sites have been visited, more specific recommendations will be made.

Historical hydronuclear testing: Characterization and remediation technologies

International Nuclear Information System (INIS)

Shaulis, L.; Wilson, G.; Jacobson, R.

1997-09-01

This report examines the most current literature and information available on characterization and remediation technologies that could be used on the Nevada Test Site (NTS) historical hydronuclear test areas. Historical hydronuclear tests use high explosives and a small amount of plutonium. The explosion scatters plutonium within a contained subsurface environment. There is currently a need to characterize these test areas to determine the spatial extent of plutonium in the subsurface and whether geohydrologic processes are transporting the plutonium away from the event site. Three technologies were identified to assist in the characterization of the sites. These technologies are the Pipe Explorer trademark, cone penetrometer, and drilling. If the characterization results indicate that remediation is needed, three remediation technologies were identified that should be appropriate, namely: capping or sealing the surface, in situ grouting, and in situ vitrification. Capping the surface would prevent vertical infiltration of water into the soil column, but would not restrict lateral movement of vadose zone water. Both the in situ grouting and vitrification techniques would attempt to immobilize the radioactive contaminants to restrict or prevent leaching of the radioactive contaminants into the groundwater. In situ grouting uses penetrometers or boreholes to inject the soil below the contaminant zone with low permeability grout. In situ vitrification melts the soil containing contaminants into a solid block. This technique would provide a significantly longer contaminant immobilization, but some research and development would be required to re-engineer existing systems for use at deep soil depths. Currently, equipment can only handle shallow depth vitrification. After existing documentation on the historical hydronuclear tests have been reviewed and the sites have been visited, more specific recommendations will be made

Implementation of fluidized granulated iron reactors in a chromate remediation process

International Nuclear Information System (INIS)

Müller, P.; Lorber, K.E.; Mischitz, R.; Weiß, C.

2014-01-01

A new approach concerning in-situ remediation on source (‘hot-spot’) decontamination of a chromate damage in connection with an innovative pump-and-treat-technique has been developed. Iron granulates show significant higher reduction rates, using fluidized bed conditions, than a literature study with a fixed bed installation of small-sized iron granules. First results from an abandoned tannery site concerning injections of sodium dithionite as a chromate reductant for the vadose zone in combination with a pump-and-treat-method, allying the advantages of granulated zero valent iron (ZVI), are reported. Reduction amounts of chromate have been found up to 88% compared with initial values in the soil after a soil water exchange of 8 pore volumes within 2.5 months. Chromate concentrations in the pumped effluent have been reduced to under the detection limit of 0.005 mg/L by treatment with ZVI in the pilot plant. - Highlights: • Fe-granules show high Cr(VI)-reduction rates using fluidized bed conditions. • No respective negligible passivation effects on the surface of the iron granulates. • P and T-method by using ZVI in a FBR is very effective for Cr(VI) remediation. • The process provides no increase in salinity of the treated effluent

Contaminant Flux Reduction Barriers for Managing Difficult-to-Treat Source Zones in Unconsolidated Media

Science.gov (United States)

2017-06-20

estimated viscosity of 3-4 cP.  Solutions-IES Novel Silica Gel/Veg-Oil Grout: 5 wt- % of emulsified vegetable oil (EVO), 10 wt-% of sodium...site must have a lower low permeability unit such as a clay to prevent up flow; and a four sided barrier is recommended (three sided barriers are...depth to groundwater (ង ft)  Transmissive zone preferably with an underlying clay layer  Good accessibility to source zone  Availability of

Understanding Fluid and Contaminant Movement in the Unsaturated Zone Using the INEEL Vadose Zone Monitoring System

International Nuclear Information System (INIS)

Hubbell, J. M.; Mattson, E. D.; Sisson, J. B.; Magnuson, S. O.

2002-01-01

DOE has hundreds of contaminated facilities and waste sites requiring cleanup and/or long-term monitoring. These contaminated sites reside in unsaturated soils (i.e. the vadose zone) above the water table. Some of these sites will require active remediation activities or removal while other sites will be placed under institutional controls. In either case, evaluating the effectiveness of the remediation strategy or institutional controls will require monitoring. Classical monitoring strategies implemented at RCRA/CERCLA sites require ground water sampling for 30 years following closure. The overall effectiveness of ground water sampling is diminished due to the fact that by the time you detect chemical transport from a waste site, a major contamination plume likely exists in the vadose zone and the aquifer. This paper suggests a more effective monitoring strategy through monitoring near the contaminant sites within the vadose zone. Vadose zone monitoring allows for quicker detection of potential contaminant transport. The INEEL Vadose Zone Monitoring System (VZMS) is becoming an accepted, cost effective monitoring technology for assessing contaminant transport at DOE facilities. This paper describes the technologies employed in the VZMS and describes how it was used at several DOE facilities. The INEEL VZMS has provided the information in developing and validating both conceptual and risk assessment models of contaminant transport at the Idaho National Engineering and Environmental Laboratory (INEEL), Oak Ridge National Laboratory (ORNL), Savannah River Site (SRS) and the Hanford site. These DOE sites exhibit a broad range of meteorologic, hydrologic and geologic conditions representative of various common geologic environments. The VZMS is comprised of advanced tensiometers, water content sensors, temperature sensors and soil and gas samplers. These instruments are placed at multiple depths in boreholes and allows for the detection of water movement in the

Characterization of the vadose zone above a shallow aquifer contaminated with gas condensate hydrocarbons

International Nuclear Information System (INIS)

Sublette, K.; Duncan, K.; Thoma, G.; Todd, T.

2002-01-01

A gas production site in the Denver Basin near Ft. Lupton, Colorado has leaked gas condensate hydrocarbons from an underground concrete tank used to store produced water. The leak has contaminated a shallow aquifer. Although the source of pollution has been removed, a plume of hydrocarbon contamination still remains for nearly 46 m from the original source. An extensive monitoring program was conducted in 1993 of the groundwater and saturated sediments. The objective was to determine if intrinsic aerobic or anaerobic bioremediation of hydrocarbons occurred at the site at a rate that would support remediation. Geochemical indicators of hydrogen biodegradation by microorganisms in the saturated zone included oxygen depletion, increased alkalinity, sulfate depletion, methane production and Fe2+ production associated with hydrogen contamination. The presence of sulfate-reducing bacteria and methanogens was also much higher in the contaminated sediments. Degraded hydrocarbon metabolites were found in contaminated groundwater. An extensive characterization of the vadose zone was conducted in which the vadose zone was sample in increments of 15 cm from the surface to the water table at contaminated and non contaminated sites. The samples were tested for individual C3+ hydrocarbons, methane, CO2, total organic carbon, total inorganic carbon, and total petroleum hydrocarbons. The vadose zone consisted of an active and aerobic bioreactor fueled by condensate hydrocarbons transported into the unsaturated zone by evaporation of hydrocarbons at the water table. It was concluded that the unsaturated zone makes an important contribution to the natural attenuation of gas condensate hydrocarbons in the area. 17 refs., 2 tabs., 28 figs

To fail is human: remediating remediation in medical education.

Science.gov (United States)

Kalet, Adina; Chou, Calvin L; Ellaway, Rachel H

2017-12-01

Remediating failing medical learners has traditionally been a craft activity responding to individual learner and remediator circumstances. Although there have been moves towards more systematic approaches to remediation (at least at the institutional level), these changes have tended to focus on due process and defensibility rather than on educational principles. As remediation practice evolves, there is a growing need for common theoretical and systems-based perspectives to guide this work. This paper steps back from the practicalities of remediation practice to take a critical systems perspective on remediation in contemporary medical education. In doing so, the authors acknowledge the complex interactions between institutional, professional, and societal forces that are both facilitators of and barriers to effective remediation practices. The authors propose a model that situates remediation within the contexts of society as a whole, the medical profession, and medical education institutions. They also outline a number of recommendations to constructively align remediation principles and practices, support a continuum of remediation practices, destigmatize remediation, and develop institutional communities of practice in remediation. Medical educators must embrace a responsible and accountable systems-level approach to remediation if they are to meet their obligations to provide a safe and effective physician workforce.

Comparison of earthquake source parameters and interseismic plate coupling variations in global subduction zones (Invited)

Science.gov (United States)

Bilek, S. L.; Moyer, P. A.; Stankova-Pursley, J.

2010-12-01

Geodetically determined interseismic coupling variations have been found in subduction zones worldwide. These coupling variations have been linked to heterogeneities in interplate fault frictional conditions. These connections to fault friction imply that observed coupling variations are also important in influencing details in earthquake rupture behavior. Because of the wealth of newly available geodetic models along many subduction zones, it is now possible to examine detailed variations in coupling and compare to seismicity characteristics. Here we use a large catalog of earthquake source time functions and slip models for moderate to large magnitude earthquakes to explore these connections, comparing earthquake source parameters with available models of geodetic coupling along segments of the Japan, Kurile, Kamchatka, Peru, Chile, and Alaska subduction zones. In addition, we use published geodetic results along the Costa Rica margin to compare with source parameters of small magnitude earthquakes recorded with an onshore-offshore network of seismometers. For the moderate to large magnitude earthquakes, preliminary results suggest a complex relationship between earthquake parameters and estimates of strongly and weakly coupled segments of the plate interface. For example, along the Kamchatka subduction zone, these earthquakes occur primarily along the transition between strong and weak coupling, with significant heterogeneity in the pattern of moment scaled duration with respect to the coupling estimates. The longest scaled duration event in this catalog occurred in a region of strong coupling. Earthquakes along the transition between strong and weakly coupled exhibited the most complexity in the source time functions. Use of small magnitude (0.5 earthquake spectra, with higher corner frequencies and higher mean apparent stress for earthquakes that occur in along the Osa Peninsula relative to the Nicoya Peninsula, mimicking the along-strike variations in

Assessment of dose contribution to population exposure from the radiation sources in the alienated Chernobyl zone

International Nuclear Information System (INIS)

Grodzinsky, D.M.; Francevych, L.K.; Koval, H.N.; Yakovlev, E.A.; Bezdrobny, Yu.V.; Proscura, N.I.; Pyantkowsky, V.L.

1997-01-01

The main dose load of Ukrainian population is caused by radionuclide-contamination of country territories, located outside the alienated zone, following Chernobyl accident. Besides, much attention could be devoted to the contribution of dose load on population, received from the radioactivity sources that were transferred out from the zone after accident. Present research and analysis of the available documents reflecting the transfer of radioactivity from the alienated zone, provided the estimates of dose load on population, resulting from transfer of the radioactivity sources via following channels: (1) direct surface flow; (2) underground waters; (3) wind-powdered route; (4) transfer with hydrobionts; (5) transfer during irrigation; (6) biogenic route; (7) transport routes and (8) route during wood transportation. Dynamics of radiation transfer through each channel was also studied for the post-accident period. Specific gravity of radioactivity transfer is determined in relation to dose load on Ukrainian population in different regions, in particular, in Dnipro river basin. The perspectives of radioactivity transfer via each of studied channels and its role in dose load on population were also analyzed. On the basis of present results the recommendations on possible arrangements are working out that aimed to reduce the dose contribution in population exposure by radioactivity source transfer from the alienated zone via channels that stipulate the largest dose loads and collective doses

Alternative Endpoints and Approaches for the Remediation of Contaminated Groundwater at Complex Sites - 13426

International Nuclear Information System (INIS)

Deeb, Rula A.; Hawley, Elisabeth L.

2013-01-01

The goal of United States (U.S.) Department of Energy's (DOE)'s environmental remediation programs is to restore groundwater to beneficial use, similar to many other Federal and state environmental cleanup programs. Based on past experience, groundwater remediation to pre-contamination conditions (i.e., drinking water standards or non-detectable concentrations) can be successfully achieved at many sites. At a subset of the most complex sites, however, complete restoration is not likely achievable within the next 50 to 100 years using today's technology. This presentation describes several approaches used at complex sites in the face of these technical challenges. Many complex sites adopted a long-term management approach, whereby contamination was contained within a specified area using active or passive remediation techniques. Consistent with the requirements of their respective environmental cleanup programs, several complex sites selected land use restrictions and used risk management approaches to accordingly adopt alternative cleanup goals (alternative endpoints). Several sites used long-term management designations and approaches in conjunction with the alternative endpoints. Examples include various state designations for groundwater management zones, technical impracticability (TI) waivers or greater risk waivers at Superfund sites, and the use of Monitored Natural Attenuation (MNA) or other passive long-term management approaches over long time frames. This presentation will focus on findings, statistics, and case studies from a recently-completed report for the Department of Defense's Environmental Security Technology Certification Program (ESTCP) (Project ER-0832) on alternative endpoints and approaches for groundwater remediation at complex sites under a variety of Federal and state cleanup programs. The primary objective of the project was to provide environmental managers and regulators with tools, metrics, and information needed to evaluate

Alternative Endpoints and Approaches for the Remediation of Contaminated Groundwater at Complex Sites - 13426

Energy Technology Data Exchange (ETDEWEB)

Deeb, Rula A.; Hawley, Elisabeth L. [ARCADIS, U.S., 2000 Powell St., 7th Floor, Emeryville, California 94608 (United States)

2013-07-01

The goal of United States (U.S.) Department of Energy's (DOE)'s environmental remediation programs is to restore groundwater to beneficial use, similar to many other Federal and state environmental cleanup programs. Based on past experience, groundwater remediation to pre-contamination conditions (i.e., drinking water standards or non-detectable concentrations) can be successfully achieved at many sites. At a subset of the most complex sites, however, complete restoration is not likely achievable within the next 50 to 100 years using today's technology. This presentation describes several approaches used at complex sites in the face of these technical challenges. Many complex sites adopted a long-term management approach, whereby contamination was contained within a specified area using active or passive remediation techniques. Consistent with the requirements of their respective environmental cleanup programs, several complex sites selected land use restrictions and used risk management approaches to accordingly adopt alternative cleanup goals (alternative endpoints). Several sites used long-term management designations and approaches in conjunction with the alternative endpoints. Examples include various state designations for groundwater management zones, technical impracticability (TI) waivers or greater risk waivers at Superfund sites, and the use of Monitored Natural Attenuation (MNA) or other passive long-term management approaches over long time frames. This presentation will focus on findings, statistics, and case studies from a recently-completed report for the Department of Defense's Environmental Security Technology Certification Program (ESTCP) (Project ER-0832) on alternative endpoints and approaches for groundwater remediation at complex sites under a variety of Federal and state cleanup programs. The primary objective of the project was to provide environmental managers and regulators with tools, metrics, and information needed

Technetium and iodine aqueous species immobilization and transformations in the presence of strong reductants and calcite-forming solutions: Remedial action implications

Energy Technology Data Exchange (ETDEWEB)

Lawter, Amanda R.; Garcia, Whitney L.; Kukkadapu, Ravi K.; Qafoku, Odeta; Bowden, Mark E.; Saslow, Sarah A.; Qafoku, Nikolla

2018-09-15

At the Hanford Site in southeastern Washington State, radionuclide (Tc-99/I-129) laden liquid wastes have been discharged to ground, resulting in vadose zone contamination, which provides a continuous source of these contaminants to groundwater. The presence of multiple contaminants increases the complexity of finding viable remediation technologies to sequester vadose zone contaminants in situ and protect groundwater. Although previous studies have shown the efficiency of zero valent iron (ZVI) and sulfur modified iron (SMI) in reducing mobile Tc(VII) to immobile Tc(IV) and iodate incorporation into calcite, the coupled effects from simultaneously using these remedial technologies have not been previously studied. In this first-of-a-kind laboratory study, we used two efficient reductants (i.e., ZVI and SMI) and calcite-forming solutions to simultaneously remove aqueous Tc(VII) and iodate via reduction and incorporation, respectively. The results confirmed that Tc(VII) was rapidly removed from the aqueous phase via reduction to Tc(IV). ZVI removed Tc(VII) faster than SMI, although both had removed the same amount by the end of the experiments. Most of the aqueous iodate was rapidly transformed to iodide, and therefore was not incorporated into calcite, but instead remained in the aqueous phase. The iodate reduction to iodide was much faster than iodate incorporation into calcite, suggesting that this remedial pathway is not efficient in removing aqueous iodate when strong reductants are present. Other experiments suggested that iodate removal via calcite precipitation should occur first and then reductants should be added for Tc(VII) removal. Although ZVI can negatively impact microbial populations and thereby inhibit natural attenuation mechanisms, only changes in the makeup of the microbial community were observed. However, these changes in the microbial community may have an impact on remediation efforts in the long term that could not be seen in a short

Identification of abiotic and biotic reductive dechlorination in a chlorinated ethene plume after thermal source remediation by means of isotopic and molecular biology tools

DEFF Research Database (Denmark)

Badin, Alice; Broholm, Mette Martina; Jacobsen, Carsten S.

2016-01-01

Thermal tetrachloroethene (PCE) remediation by steam injection in a sandy aquifer led to the release of dissolved organic carbon (DOC) from aquifer sediments resulting in more reduced redox conditions, accelerated PCE biodegradation, and changes in microbial populations. These changes were...... documented by comparing data collected prior to the remediation event and eight years later. Based on the premise that dual C-Cl isotope slopes reflect ongoing degradation pathways, the slopes associated with PCE and TCE suggest the predominance of biotic reductive dechlorination near the source area. PCE...... is supported by the relative lack of Dhc in the downgradient part of the plume. The results of this study show that thermal remediation can enhance the biodegradation of chlorinated ethenes, and that this effect can be traced to the mobilisation of DOC due to steam injection. This, in turn, results in more...

Radiotracer technique to study pollutant behavior in the vadose zone for groundwater protection

International Nuclear Information System (INIS)

Kulkarni, U.P.; Sinha, U.K.; Navada, S.V.; Datta, P.S.; Sud, Y.K.; Kulkarni, K.M.; Aggrawal, P.; )

2004-01-01

Pollutants are generated either by industrial or agricultural activity. Pollutants produced due to industrial activities fall into point source category and those generated from agricultural are grouped into extended source category. Under an International Atomic Energy Agency/Coordinated Research Program study, emphasis has been given on transport of pollutants, generated from agricultural activities, in particular, due to the application of fertilizer inputs to a variety of crops. Pollutants take entry through the vadose zone and ultimately join the saturated zone. Once groundwater is polluted it is rather difficult or impossible to take remedial measures for groundwater protection. Groundwater being an important natural resource, it is important to protect it from getting polluted. It is hence essential to have a clear understanding of the complex processes (physical, biological and chemical etc.) undergoing in the unsaturated zone. Radiotracers give good insight about the pollutant behavior in the vadose zone. Tritiated water and 60 Co (a gamma emitting tracer in the cyanide complex form) were used as tracers and were injected at 60 cm depth in the vadose zone of IARI farm for pollutant transport study. Tritium and 60 Co tracer displacements were measured by liquid scintillation and sodium iodide scintillation method respectively. It was found that the tritium tracer moved up to 2.4 meters in six months and part of the tritium tracer was exchanged with immobile water in the soil, as three distinct peaks were observed in tritium profile. 60 Co and tritium tracers were found to move with the same velocity in the vadose zone. These tracer studies indicate that the pollutants may reach the groundwater in about three years. (author)

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

Remediation of hazardous waste sites by heap leaching

International Nuclear Information System (INIS)

Samani, Z.; Hanson, A.; Dwyer, B.

1994-01-01

Efforts are being made to devise technologies and treatment systems to remediate contaminated soil-on site without generating significant wastes for off-site disposal. Heap leaching, a technique used extensively in the mining industry, has been investigated as a method for remediation of hazardous chemical contamination of the vadose zone. In the mining industry, metal-bearing ore is excavated and mounded on a pad. The metals are removed by passing a special leaching solution through the ore. In this study, the removal of chromium(VI) from the New Mexico soils (sand, sandy loam, and clay) using heap leaching was evaluated at a column scale. The heap leaching study demonstrated greater than 99% removal of Cr(VI) from all three soils using tap water as the leaching agent. (author) 13 figs., 5 tabs., 21 refs

Enhanced bioremediation as a cost effective approach following thermally enhanced soil vapour extraction for sites requiring remediation of chlorinated solvents - 16296

International Nuclear Information System (INIS)

Kozlowska, Anna-Maria; Kahlon, Manjit S.; Langford, Steve R.; Williams, Haydn G.

2009-01-01

Thermally enhanced bioremediation can be a more cost-effective alternative to full scale in-situ thermal treatment especially for sites contaminated with chlorinated solvents, where reductive dechlorination is or might be a dominant biological step. The effect of Thermally Enhanced Soil Vapour Extraction (TESVE) on indigenous microbial communities and the potential for subsequent biological polishing of chlorinated solvents was investigated in field trials at the Western Storage Area (WSA) - RSRL (formerly United Kingdom Atomic Energy Authority - UKAEA) Oxfordshire, UK. The WSA site had been contaminated with various chemicals including mineral oil, chloroform, trichloroethane (TCA), carbon tetrachloride and tetrachloroethene (PCE). The contamination had affected the unsaturated zone, groundwater in the chalk aquifer and was a continuing source of groundwater contamination below the WSA. During TESVE the target treatment zone was heated to above the boiling point of water increasing the degree of volatilization of contaminants of concern (CoC), which were mobilised and extracted in the vapour phase. A significant reduction of concentrations of chlorinated solvent in the unsaturated zone was achieved by the full-scale application of TESVE - In Situ Thermal Desorption (ISTD) technology. The rock mass temperature within target treatment zone remained in the range of 35 deg. - 44 deg. C, 6 months after cessation of heating. The concentration of chlorinated ethenes and other CoC were found to be significantly lower adjacent to the thermal treatment area and 1 to 2 orders of magnitude lower within the thermal treatment zone. Samples were collected within and outside the thermal treatment zone using BioTraps R (passive, in- situ microbial samplers) from which the numbers of specific bacteria were measured using quantitative polymerase chain reaction (qPCR) methods of analysis. High populations of reductive de-chlorinators such as Dechalococcoides spp. and Dehalobacter spp

Earthquake spectra and near-source attenuation in the Cascadia subduction zone

Science.gov (United States)

Gomberg, J.; Creager, K.; Sweet, J.; Vidale, J.; Ghosh, A.; Hotovec, A.

2012-05-01

Models of seismic source displacement spectra are flat from zero to some corner frequency, fc, regardless of source type. At higher frequencies spectral models decay as f-1 for slow events and as f-2 for fast earthquakes. We show that at least in Cascadia, wave propagation effects likely control spectral decay rates above ˜2 Hz. We use seismograms from multiple small-aperture arrays to estimate the spectral decay rates of near-source spectra of 37 small `events' and find strong correlation between source location and decay rate. The decay rates (1) vary overall by an amount in excess of that inferred to distinguish slow sources from fast earthquakes, (2) are indistinguishable for sources separated by a few tens of km or less, and (3) separate into two populations that correlate with propagation through and outside a low-velocity zone imaged tomographically. We find that some events repeat, as is characteristic of low-frequency earthquakes (LFEs), but have spectra similar to those of non-repeating earthquakes. We also find no correlation between spectral decay rates and rates of ambient tremor activity. These results suggest that earthquakes near the plate boundary, at least in Cascadia, do not distinctly separate into `slow' and `fast' classes, and correctly accounting for propagation effects is necessary to characterize sources.

Development of field-wide risk based remediation objectives for an aging oil field : Devon Canada Swan Hills Field

Energy Technology Data Exchange (ETDEWEB)

Brewster, M.; North, C.; Leighton-Boyce, G. [WorleyParsons Komex, Calgary, AB (Canada); Moore, D. [Devon Canada Corp., Calgary, AB (Canada)

2006-07-01

The development of field-wide risk based remediation objectives for the aging Devon Canada Swan Hills oil field was examined along with the key components of the closure strategy. These included source removal to the extent practical, long term monitoring, and achievable risk-based remedial objectives that were appropriate to the remote boreal forest setting of the Swan Hills field. A two stage approach was presented. The first stage involved a field wide background framework which included defining areas of common physical and ecological setting and developing appropriate exposure scenarios. The second stage involved site-specific risk assessments which included adjusting for site-specific conditions and an early demonstration project to prove the concept. A GIS approach was used to identify areas of common physical and ecological setting including: physiography; surface water; land use; vegetation ecozones; surficial and bedrock geology; and water well use. Species lists were compiled for vegetation, terrestrial wildlife (mammals, birds, amphibians), and aquatic species (fish and invertebrates). Major contaminant sources, problem formulation, vegetation bioassays, invertebrate bioassays, black spruce emergence, and guideline development were other topics covered during the presentation. Last, a summary of progress was presented. A field-wide review and development of risk zones and site-specific risk assessment has been completed. A regulatory review is underway. tabs., figs.

Testing the Nanoparticle-Allostatic Cross Adaptation-Sensitization Model for Homeopathic Remedy Effects

Science.gov (United States)

Bell, Iris R.; Koithan, Mary; Brooks, Audrey J.

2012-01-01

Key concepts of the Nanoparticle-Allostatic Cross-Adaptation-Sensitization (NPCAS) Model for the action of homeopathic remedies in living systems include source nanoparticles as low level environmental stressors, heterotypic hormesis, cross-adaptation, allostasis (stress response network), time-dependent sensitization with endogenous amplification and bidirectional change, and self-organizing complex adaptive systems. The model accommodates the requirement for measurable physical agents in the remedy (source nanoparticles and/or source adsorbed to silica nanoparticles). Hormetic adaptive responses in the organism, triggered by nanoparticles; bipolar, metaplastic change, dependent on the history of the organism. Clinical matching of the patient’s symptom picture, including modalities, to the symptom pattern that the source material can cause (cross-adaptation and cross-sensitization). Evidence for nanoparticle-related quantum macro-entanglement in homeopathic pathogenetic trials. This paper examines research implications of the model, discussing the following hypotheses: Variability in nanoparticle size, morphology, and aggregation affects remedy properties and reproducibility of findings. Homeopathic remedies modulate adaptive allostatic responses, with multiple dynamic short- and long-term effects. Simillimum remedy nanoparticles, as novel mild stressors corresponding to the organism’s dysfunction initiate time-dependent cross-sensitization, reversing the direction of dysfunctional reactivity to environmental stressors. The NPCAS model suggests a way forward for systematic research on homeopathy. The central proposition is that homeopathic treatment is a form of nanomedicine acting by modulation of endogenous adaptation and metaplastic amplification processes in the organism to enhance long-term systemic resilience and health. PMID:23290882

Tank waste remediation system vadose zone program plan

International Nuclear Information System (INIS)

Fredenburg, E.A.

1998-01-01

The objective of the vadose zone characterization under this program is to develop a better conceptual geohydrologic model of identified tank farms which will be characterized so that threats to human health and the environment from past leaks and spills, intentional liquid discharges, potential future leaks during retrieval, and from residual contaminants that may remain in tank farms at closure can be explicitly addressed in decision processes. This model will include geologic, hydrologic, and hydrochemical parameters as defined by the requirements of each of the TWRS programs identified here. The intent of this TWRS Vadose Zone Program Plan is to provide justification and an implementation plan for the following activities: Develop a sufficient understanding of subsurface conditions and transport processes to support decisions on management, cleanup, and containment of past leaks, spills, and intentional liquid discharges; Develop a sufficient understanding of transport processes to support decisions on controlling potential retrieval leaks; Develop a sufficient understanding of transport processes to support decisions on tank farm closure, including allowable residual waste that may remain at closure; and Provide new information on geotechnical properties in the 200 Area to supplement data used for design and performance assessment for immobilized low-activity waste disposal facilities

Tank waste remediation system vadose zone program plan

Energy Technology Data Exchange (ETDEWEB)

Fredenburg, E.A.

1998-07-27

The objective of the vadose zone characterization under this program is to develop a better conceptual geohydrologic model of identified tank farms which will be characterized so that threats to human health and the environment from past leaks and spills, intentional liquid discharges, potential future leaks during retrieval, and from residual contaminants that may remain in tank farms at closure can be explicitly addressed in decision processes. This model will include geologic, hydrologic, and hydrochemical parameters as defined by the requirements of each of the TWRS programs identified here. The intent of this TWRS Vadose Zone Program Plan is to provide justification and an implementation plan for the following activities: Develop a sufficient understanding of subsurface conditions and transport processes to support decisions on management, cleanup, and containment of past leaks, spills, and intentional liquid discharges; Develop a sufficient understanding of transport processes to support decisions on controlling potential retrieval leaks; Develop a sufficient understanding of transport processes to support decisions on tank farm closure, including allowable residual waste that may remain at closure; and Provide new information on geotechnical properties in the 200 Area to supplement data used for design and performance assessment for immobilized low-activity waste disposal facilities.

Sustainability: A new imperative in contaminated land remediation

International Nuclear Information System (INIS)

Hou, Deyi; Al-Tabbaa, Abir

2014-01-01

Highlights: • Reviewed the emerging green and sustainable remediation movement in the US and Europe. • Identified three sources of pressures for emphasizing sustainability in the remediation field. • Presented a holistic view of sustainability considerations in remediation. • Developed an integrated framework for sustainability assessment and decision making. - Abstract: Land is not only a critical component of the earth's life support system, but also a precious resource and an important factor of production in economic systems. However, historical industrial operations have resulted in large areas of contaminated land that are only slowly being remediated. In recent years, sustainability has drawn increasing attention in the environmental remediation field. In Europe, there has been a movement towards sustainable land management; and in the US, there is an urge for green remediation. Based on a questionnaire survey and a review of existing theories and empirical evidence, this paper suggests the expanding emphasis on sustainable remediation is driven by three general factors: (1) increased recognition of secondary environmental impacts (e.g., life-cycle greenhouse gas emissions, air pollution, energy consumption, and waste production) from remediation operations, (2) stakeholders’ demand for economically sustainable brownfield remediation and “green” practices, and (3) institutional pressures (e.g., social norm and public policy) that promote sustainable practices (e.g., renewable energy, green building, and waste recycling). This paper further argues that the rise of the “sustainable remediation” concept represents a critical intervention point from where the remediation field will be reshaped and new norms and standards will be established for practitioners to follow in future years. This paper presents a holistic view of sustainability considerations in remediation, and an integrated framework for sustainability assessment and decision making

Soil radiological characterisation and remediation at CIEMAT

International Nuclear Information System (INIS)

Correa, Cristina; Garcia Tapias, Esther; Leganes, Jose

2012-01-01

Located in Madrid, CIEMAT is the Spanish Centre for Energy-Related, Environmental and Technological Research. It used to have more than 60 facilities in operation that allowed a wide range of activities in the nuclear field and in the application of ionising radiations. At present, the centre includes several facilities; some of them are now obsolete, shut down and in dismantling phases. In 2000 CIEMAT started the 'Integrated plan for the improvement of CIEMAT facilities (PIMIC)', which includes activities for the decontamination, dismantling, rehabilitation of obsolete installations and soil remediation activities. A small contaminated area named with the Spanish word 'Lenteja' (Lentil), has had to be remediate and restored. In the 70's, an incidental leakage of radioactive liquid occurred during a transference operation from the Reprocessing Plant to the Liquid Treatment Installation, and contaminated about 1000 m 3 of soil. Remediation activities in this area started with an exhaustive radiological characterisation of the soil, including surface samples and up to 16 meters boreholes, and the development of a comprehensive radiological characterization methodology for pre-classification of materials. Once the framework was defined the following tasks were being carried out: preparation of the area, soil extraction activities and final radiological characterisation for release purposes. Next step will be the refilling of the resulting hole from the removal soil activities. This paper will describe the soil radiological characterization and remediation activities at the Lentil Zone in Ciemat Research Centre. (authors)

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

Comparison of approaches for assessing sustainable remediation of contaminated sites

DEFF Research Database (Denmark)

Søndergaard, Gitte Lemming; Binning, Philip John; Bjerg, Poul Løgstrup

2017-01-01

It has been estimated that there are approximately 2.5 million potentially contaminated sites in Europe. Of these, approximately 340,000 sites are thought to be contaminated to a degree that may require remediation (Joint Research Center, 2014). Until recently, remediation was considered...... to be inherently green or sustainable since it removes a contaminant problem. However, it is now broadly recognized that while remediation is intended to address a local environmental threat, it may cause other local, regional and global impacts on the environment, society and economy. Over the last decade......, the broader assessment of these criteria is occurring in a movement toward ‘sustainable remediation’. This paper aims to review the available methods for assessing the sustainability of remediation alternatives. Sustainable remediation seeks to reduce direct contaminant point source impacts on the environment...

300-FF-1 remedial design report/remedial action work plan

Energy Technology Data Exchange (ETDEWEB)

Gustafson, F.W.

1997-02-01

The 300 Area has been divided into three operable units 300-FF-1, 300-FF-2, and 300-FF-5 all of which are in various stages of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) process. The 300-FF-1 Operable Unit, the subject of this report, includes liquid waste disposal sites, landfills, and a burial ground. This Remedial Design Report/Remedial Action Work Plan (RDR/RAWP) provides a summary description of each waste site included in the 300-FF-1 Operable Unit, the basis for remedial actions to be taken, and the remedial action approach and management process for implementing these actions. The remedial action approach and management sections provide a description of the remedial action process description, the project schedule, the project team, required planning documentation, the remedial action change process, the process for verifying attainment of the remedial action goals, and the required CERCLA and RCRA closeout documentation. Appendix A provides additional details on each waste site. In addition to remediation of the waste sites, waste generated during the remedial investigation/feasibility study portions of the project will also be disposed at the Environmental Restoration Disposal Facility (ERDF). Appendix B provides a summary of the modeling performed in the 300-FF-1 Phase 3 FS and a description of the modeling effort to be used to show attainment of the remedial action goals. Appendix C provides the sampling and analysis plan (SAP) for all sampling and field-screening activities performed during remediation and for verification of attainment with the remedial action goals. Appendix D provides the public involvement plan, prepared to ensure information is provided to the public during remedial design and remedial action processes.

300-FF-1 remedial design report/remedial action work plan

International Nuclear Information System (INIS)

Gustafson, F.W.

1997-02-01

The 300 Area has been divided into three operable units 300-FF-1, 300-FF-2, and 300-FF-5 all of which are in various stages of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) process. The 300-FF-1 Operable Unit, the subject of this report, includes liquid waste disposal sites, landfills, and a burial ground. This Remedial Design Report/Remedial Action Work Plan (RDR/RAWP) provides a summary description of each waste site included in the 300-FF-1 Operable Unit, the basis for remedial actions to be taken, and the remedial action approach and management process for implementing these actions. The remedial action approach and management sections provide a description of the remedial action process description, the project schedule, the project team, required planning documentation, the remedial action change process, the process for verifying attainment of the remedial action goals, and the required CERCLA and RCRA closeout documentation. Appendix A provides additional details on each waste site. In addition to remediation of the waste sites, waste generated during the remedial investigation/feasibility study portions of the project will also be disposed at the Environmental Restoration Disposal Facility (ERDF). Appendix B provides a summary of the modeling performed in the 300-FF-1 Phase 3 FS and a description of the modeling effort to be used to show attainment of the remedial action goals. Appendix C provides the sampling and analysis plan (SAP) for all sampling and field-screening activities performed during remediation and for verification of attainment with the remedial action goals. Appendix D provides the public involvement plan, prepared to ensure information is provided to the public during remedial design and remedial action processes

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.

Waste Area Grouping 2 Remedial Investigation Phase 1 Seep Task data report: Contaminant source area assessment

International Nuclear Information System (INIS)

Hicks, D.S.

1996-03-01

This report presents the findings of the Waste Area Grouping (WAG) 2, Phase 1 Remedial Investigation (RI) Seep Task efforts during 1993 and 1994 at Oak Ridge National Laboratory (ORNL). The results presented here follow results form the first year of sampling, 1992, which are contained in the Phase 1 RI report for WAG 2 (DOE 1995a). The WAG 2 Seep Task efforts focused on contaminants in seeps, tributaries, and main streams within the White Oak Creek (WOC) watershed. This report is designed primarily as a reference for contaminants and a resource for guiding remedial decisions. Additional in-depth assessments of the Seep Task data may provide clearer understandings of contaminant transport from the different source areas in the WOC watershed. WAG 2 consists of WOC and its tributaries downstream of the ORNL main plant area, White Oak Lake, the White Oak Creek Embayment of the Clinch River, and the associated flood plains and subsurface environment. The WOC watershed encompasses ORNL and associated WAGs. WAG 2 acts as an integrator for contaminant releases from the contaminated sites at ORNL and as the conduit transporting contaminants to the Clinch River. The main objectives of the Seep Task were to identify and characterize seeps, tributaries and source areas that are responsible for the contaminant releases to the main streams in WAG 2 and to quantify their input to the total contaminant release from the watershed at White Oak Dam (WOD). Efforts focused on 90 Sr, 3 H, and 137 Cs because these contaminants pose the greatest potential human health risk from water ingestion at WOD. Bimonthly sampling was conducted throughout the WOC watershed beginning in March 1993 and ending in August 1994. Samples were also collected for metals, anions, alkalinity, organics, and other radionuclides

A ''dog gone'' restoration project: Remediation of an AEC research facility

International Nuclear Information System (INIS)

Huff, P.E.; Brooks, B.T.

1994-01-01

This facility was established in 1958 by the Atomic Energy Commission. Research at the facility originally focused on the health effects from chronic exposures to radionuclides, primarily strontium 90 ( 90 Sr) and radium 226 ( 226 Ra), using beagles to simulate radiation effects on humans. In 1988 the Department of Energy (DOE) decided to close out the research program, shut down the facility and turn it over to the tenant after remediation. This paper examines the remediation activities relative to Animal Hospitals 1 and 2 (AH-1 and AH-2), the cobalt 60 ( 60 Co) source and the Specimen Storage Room. Remediation of this facility took place over one year period beginning in August 1992. Portions of the facility not requiring remediation are now a part of an ongoing research facility. While excluded from areas where remediation took place, facility personnel and others were in close proximity to the remediation, sometimes separated only by a common building wall. This close proximity required remediation techniques that stressed contamination control

Feasibility and Performance of Full-Scale In-situ Remediation of TCE by ERD in Clay Tills

DEFF Research Database (Denmark)

Broholm, Mette Martina; Damgaard, Ida; Chambon, Julie Claire Claudia

The feasibility and performance of full-scale applications of ERD in clay tills were investigated in a research project including 2 sites in Denmark, which have been undergoing remediation since 2006. At both sites organic substrates and bioaugmentation cultures have been injected in TCE-contamin......The feasibility and performance of full-scale applications of ERD in clay tills were investigated in a research project including 2 sites in Denmark, which have been undergoing remediation since 2006. At both sites organic substrates and bioaugmentation cultures have been injected in TCE...... been applied. The results showed that the chlorinated solvent TCE was converted into its daughter products (cDCE, VC and ethene) but complete conversion of contaminants to ethene (as expected) was not achieved within a timeframe of 4 years. Large variation in the effect of ERD in the clay matrix...... features in some parts of the clay tills. The bioactive zones may expand in zones where both donor and chlorinated compounds are present. In some cores TCE was depleted (degraded to DCE) in zones up to 1.8 m thick – an extent which could not be explained by diffusive loss to narrow bioactive zones. Hence...

Environmental Remediation Science at Beamline X26A at the National Synchrotron Light Source- Final Report

Energy Technology Data Exchange (ETDEWEB)

Bertsch, Paul [Univ. of Kentucky, Lexington, KY (United States)

2013-11-07

The goal of this project was to provide support for an advanced X-ray microspectroscopy facility at the National Synchrotron Light Source, Brookhaven National Laboratory. This facility is operated by the University of Chicago and the University of Kentucky. The facility is available to researchers at both institutions as well as researchers around the globe through the general user program. This facility was successfully supported during the project period. It provided access to advanced X-ray microanalysis techniques which lead to fundamental advances in understanding the behavior of contaminants and geochemistry that is applicable to environmental remediation of DOE legacy sites as well as contaminated sites around the United States and beyond.

Localization of epileptogenic zones in Lennox–Gastaut syndrome using frequency domain source imaging of intracranial electroencephalography: a preliminary investigation

International Nuclear Information System (INIS)

Cho, Jae-Hyun; Jung, Young-Jin; Kim, Jeong-Youn; Im, Chang-Hwan; Kang, Hoon-Chul; Kim, Heung Dong; Yoon, Dae Sung; Lee, Yong-Ho

2013-01-01

Although intracranial electroencephalography (iEEG) has been widely used to localize epileptogenic zones in epilepsy, visual inspection of iEEG recordings does not always result in a favorable surgical outcome, especially in secondary generalized epilepsy such as Lennox–Gastaut syndrome (LGS). Various computational iEEG analysis methods have recently been introduced to confirm the visual inspection results. Of these methods, high gamma oscillation in iEEG has attracted interest because a series of studies have reported a close relationship between epileptogenic zones and cortical areas with high gamma oscillation. Meanwhile, frequency domain source imaging of EEG and MEG oscillations has proven to be a useful auxiliary tool for identifying rough locations of epileptogenic zones. To the best of our knowledge, however, frequency domain source imaging of high gamma iEEG oscillations has not been studied. In this study, we investigated whether the iEEG-based frequency domain source imaging of high gamma oscillation (60–100 Hz) would be a useful supplementary tool for identifying epileptogenic zones in patients with secondary generalized epilepsy. The method was applied to three successfully operated on LGS patients, whose iEEG contained some ictal events with distinct high gamma oscillations before seizure onset. The resultant cortical source distributions were compared with surgical resection areas and with high gamma spectral power distributions on the intracranial sensor plane. While the results of the sensor-level analyses contained many spurious activities, the results of frequency domain source imaging coincided better with the surgical resection areas, suggesting that the frequency domain source imaging of iEEG high gamma oscillations might help enhance the accuracy of pre-surgical evaluations of patients with secondary generalized epilepsy. (paper)

Adaptive remediation using portable treatment units

International Nuclear Information System (INIS)

Bahowick, S.; Folsom, E.; Pico, T.

1996-01-01

Lawrence Livermore National Laboratory (LLNL) is using adaptive remediation to optimize their environmental restoration strategy. Adaptive remediation uses hydrostratigraphic analysis to gain a better understanding of the subsurface characteristics, hydraulic tests to optimize contaminant transport models, and Portable Treatment Units (PTUs) as an alternative to fixed facilities. Hydrostratigraphic analysis is an optimization tool that improves the ability to identify and target contaminant migration pathways, identify the relationship between plumes and source areas, and better define hydraulic capture areas. Hydraulic tests, performed with PTUs, provide valuable data about subsurface characteristics. As clean up progresses, PTUs can be moved to the appropriate extraction wells to optimize contaminant mass removal. PTUs can also be placed to support innovative treatment technologies such as steam injection and microbial filters. Construction of PTUs will reduce by one-half the capital costs of building the rest of the fixed treatment system planned in the Record of Decision. Regulatory agencies are receptive to the use of the PTUs because the same treatment technology is being used and the PTUs will be able to clean up the plume cheaper and faster. Using adaptive remediation, LLNL is more effectively implementing remediation plans, improving cleanup time, and reducing project costs

Chlorinated volatile organic compounds (Cl-VOCs) in environment - sources, potential human health impacts, and current remediation technologies.

Science.gov (United States)

Huang, Binbin; Lei, Chao; Wei, Chaohai; Zeng, Guangming

2014-10-01

Chlorinated volatile organic compounds (Cl-VOCs), including polychloromethanes, polychloroethanes and polychloroethylenes, are widely used as solvents, degreasing agents and a variety of commercial products. These compounds belong to a group of ubiquitous contaminants that can be found in contaminated soil, air and any kind of fluvial mediums such as groundwater, rivers and lakes. This review presents a summary of the research concerning the production levels and sources of Cl-VOCs, their potential impacts on human health as well as state-of-the-art remediation technologies. Important sources of Cl-VOCs principally include the emissions from industrial processes, the consumption of Cl-VOC-containing products, the disinfection process, as well as improper storage and disposal methods. Human exposure to Cl-VOCs can occur through different routes, including ingestion, inhalation and dermal contact. The toxicological impacts of these compounds have been carefully assessed, and the results demonstrate the potential associations of cancer incidence with exposure to Cl-VOCs. Most Cl-VOCs thus have been listed as priority pollutants by the Ministry of Environmental Protection (MEP) of China, Environmental Protection Agency of the U.S. (U.S. EPA) and European Commission (EC), and are under close monitor and strict control. Yet, more efforts will be put into the epidemiological studies for the risk of human exposure to Cl-VOCs and the exposure level measurements in contaminated sites in the future. State-of-the-art remediation technologies for Cl-VOCs employ non-destructive methods and destructive methods (e.g. thermal incineration, phytoremediation, biodegradation, advanced oxidation processes (AOPs) and reductive dechlorination), whose advantages, drawbacks and future developments are thoroughly discussed in the later sections. Copyright © 2014 Elsevier Ltd. All rights reserved.

A comparison of pre- and post-remediation water quality, Mineral Creek, Colorado

Science.gov (United States)

Runkel, R.L.; Bencala, K.E.; Kimball, B.A.; Walton-Day, K.; Verplanck, P.L.

2009-01-01

Pre- and post-remediation data sets are used herein to assess the effectiveness of remedial measures implemented in the headwaters of the Mineral Creek watershed, where contamination from hard rock mining has led to elevated metal concentrations and acidic pH. Collection of pre- and post-remediation data sets generally followed the synoptic mass balance approach, in which numerous stream and inflow locations are sampled for the constituents of interest and estimates of streamflow are determined by tracer dilution. The comparison of pre- and post-remediation data sets is confounded by hydrologic effects and the effects of temporal variation. Hydrologic effects arise due to the relatively wet conditions that preceded the collection of pre-remediation data, and the relatively dry conditions associated with the post-remediation data set. This difference leads to a dilution effect in the upper part of the study reach, where pre-remediation concentrations were diluted by rainfall, and a source area effect in the lower part of the study reach, where a smaller portion of the watershed may have been contributing constituent mass during the drier post-remediation period. A second confounding factor, temporal variability, violates the steady-state assumption that underlies the synoptic mass balance approach, leading to false identification of constituent sources and sinks. Despite these complications, remedial actions completed in the Mineral Creek headwaters appear to have led to improvements in stream water quality, as post-remediation profiles of instream load are consistently lower than the pre-remediation profiles over the entire study reach for six of the eight constituents considered (aluminium, arsenic, cadmium, copper, iron, and zinc). Concentrations of aluminium, cadmium, copper, lead, and zinc remain above chronic aquatic-life standards, however, and additional remedial actions may be needed. Future implementations of the synoptic mass balance approach should be

A Manual of Cherokee Herbal Remedies: History, Information, Identification, Medicinal Healing.

Science.gov (United States)

Schafer, Patricia D.

This thesis reports on the research of 25 plants, used as herbal remedies since the 1800s by the author's Native American ancestors (the Day family) and the Cherokee tribe. The plants were identified in four state parks in southwestern Indiana. Information sources included the research literature, articles on Cherokee herbal remedies, and…

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

Remediation of the low-level radioactive waste tailing pond at Kowary, Poland

International Nuclear Information System (INIS)

Goerner, R.; Hartsch, J.; Koszela, J.; Krzyskow, A.; Machniewicz, B.; Sennewald, R.; Sowa, J.

2002-03-01

The last remaining uranium mining tailing pond in Poland, situated at Kowary, was the subject of the Kowary Tailing Pond Remediation Programme financed by Polish public bodies (70%) and by the European Commission (30%) within the framework of its programme of co-operation on radioactive waste issues with candidate countries. The EC-part of the project comprised investigations of the site, project management duties and large-scale civil works following the initial remediation planning performed by the Wroclaw University of Technology (WUT) in 1998-2000. The EC-part was contracted to G.E.O.S. Freiberg Ingenieurgesellschaft mbH following an Open Call for Tender launched by the European Commission in 1999. The following general tasks were performed in close co-operation with WUT, with the construction works subcontracted to local companies, as proposed in the Terms of Reference (TOR) of the EC-part: review of General Remediation Plan (GRP), technical design of the pond cover, construction work: internal drainage system, pond cover and site reclamation. From the information in the TOR, the following aims of remediation were defined: minimise the detrimental impact of the tailing pond on the environment, provide long-term stability of the slopes surrounding the pond, ensure the remediated site is in harmony with the surrounding natural scenery. Based on the experience gathered in similar projects, which had been running under PHARE-MCE or which belonged to the WISMUT-remediation programme in Germany, cost efficient remediation solutions were designed in close co-operation with all involved parties. They were delineated in the detailed planning documents approved in the overall remediation programme managed by WUT. The planned remediation works were prepared and performed successfully according to Polish law and in agreement with the competent local authorities. The aims of remediation were met. However, some additional tasks have been recommended in zones adjacent to the

Deep Vadose Zone Treatability Test for the Hanford Central Plateau: Interim Post-Desiccation Monitoring Results, Fiscal Year 2014

Energy Technology Data Exchange (ETDEWEB)

Truex, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Strickland, Christopher E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Christian D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Timothy C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Clayton, Ray E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chronister, Glen B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2014-09-01

Over decades of operation, the U.S. Department of Energy (DOE) and its predecessors have released nearly 2 trillion L (450 billion gal.) of liquid into the vadose zone at the Hanford Site. Much of this discharge of liquid waste into the vadose zone occurred in the Central Plateau, a 200 km² (75 mi²) area that includes approximately 800 waste sites. Some of the inorganic and radionuclide contaminants in the deep vadose zone at the Hanford Site are at depths below the limit of direct exposure pathways, but may need to be remediated to protect groundwater. The Tri-Party Agencies (DOE, U.S. Environmental Protection Agency, and Washington State Department of Ecology) established Milestone M 015 50, which directed DOE to submit a treatability test plan for remediation of technetium-99 (Tc-99) and uranium in the deep vadose zone. These contaminants are mobile in the subsurface environment and have been detected at high concentrations deep in the vadose zone, and at some locations have reached groundwater. Testing technologies for remediating Tc-99 and uranium will also provide information relevant for remediating other contaminants in the vadose zone. A field test of desiccation is being conducted as an element of the DOE test plan published in March 2008 to meet Milestone M 015 50. The active desiccation portion of the test has been completed. Monitoring data have been collected at the field test site during the post-desiccation period and are reported herein. This is an interim data summary report that includes about 3 years of post-desiccation monitoring data. The DOE field test plan proscribes a total of 5 years of post-desiccation monitoring.

A strategy for improving pump and treat ground water remediation

International Nuclear Information System (INIS)

Hoffman, F.

1992-07-01

Established pump and treat ground water remediation has a reputation for being too expensive and time consuming, especially when cleanup standards are set at very low levels, e.g., 50 ft below ground surface) widespread ground water contamination. The perceived shortcomings of pump and treat result from the (1) tendency of most contaminants to sorb to formation materials, thus retarding contaminant removal; (2) geologic complexity, which requires detailed characterization for the design of optimal extraction systems within available resources; and (3) failure to apply dynamic well field management techniques. An alternative strategy for improving pump and treat ground water remediation consists of (1) detailed characterization of the geology, hydrology, and chemistry; (2) use of computer-aided data interpretation, data display, and decision support systems; (3) removal of sources, if possible; (4) initial design for plume containment and source remediation; (5) phased installation of the well field; (6) detailed monitoring of the remediation; (7) active ongoing re-evaluation of the operating well field, including redesign as appropriate (dynamic management); (8) re-injection of treated ground water to speed the flushing of contaminants; and (9) setting of appropriate cleanup levels or goals. Use of some or all of these techniques can dramatically reduce the time required to achieve cleanup goals and thus the cost of ground water remediation

Monitoring remediation of trichloroethylene using a chemical fiber optic sensor: Field studies

International Nuclear Information System (INIS)

Colston, B.W.; Brown, S.B.; Langry, K.; Daley, P.; Milanovich, F.P.

1994-06-01

Current US Department of Energy (DOE) policy requires characterization and subsequent remediation of areas where trichloroethylene (TCE) has been discharged into the soil and groundwater. Technology that allows trace quantities of this contaminant to be measured in situ on a continuous basis is needed. Fiber optic chemical sensors offer a promising low cost solution. Field tests of such a fiber optic chemical sensor for TCE have recently been completed. Sensors have been used to measure TCE contamination at Savannah River Site (SRS) and Lawrence Livermore National Laboratory Site 300 (S300) in the groundwater and vadose zones. Both sites are currently undergoing remediation processes

VAMOS: The verification and monitoring options study: Current research options for in-situ monitoring and verification of contaminant remediation and containment within the vadose zone

International Nuclear Information System (INIS)

Betsill, J.D.; Gruebel, R.D.

1995-09-01

The Verification and Monitoring Options Study Project (VAMOS) was established to identify high-priority options for future vadose-zone environmental research in the areas of in-situ remediation monitoring, post-closure monitoring, and containment emplacement and verification monitoring. VAMOS examined projected needs not currently being met with applied technology in order to develop viable monitoring and verification research options. The study emphasized a compatible systems approach to reinforce the need for utilizing compatible components to provide user friendly site monitoring systems. To identify the needs and research options related to vadose-zone environmental monitoring and verification, a literature search and expert panel forums were conducted. The search included present drivers for environmental monitoring technology, technology applications, and research efforts. The forums included scientific, academic, industry, and regulatory environmental professionals as well as end users of environmental technology. The experts evaluated current and future monitoring and verification needs, methods for meeting these needs, and viable research options and directions. A variety of high-priority technology development, user facility, and technology guidance research options were developed and presented as an outcome of the literature search and expert panel forums

Remediation of a marine shore tailings deposit and the importance of water-rock interaction on element cycling in the coastal aquifer.

Science.gov (United States)

Dold, Bernhard; Diaby, Nouhou; Spangenberg, Jorge E

2011-06-01

We present the study of the geochemical processes associated with the first successful remediation of a marine shore tailings deposit in a coastal desert environment (Bahía de Ite, in the Atacama Desert of Peru). The remediation approach implemented a wetland on top of the oxidized tailings. The site is characterized by a high hydraulic gradient produced by agricultural irrigation on upstream gravel terraces that pushed river water (∼500 mg/L SO(4)) toward the sea and through the tailings deposit. The geochemical and isotopic (δ(2)H(water) and δ(18)O(water), δ(34)S(sulfate), δ(18)O(sulfate)) approach applied here revealed that evaporite horizons (anhydrite and halite) in the gravel terraces are the source of increased concentrations of SO(4), Cl, and Na up to ∼1500 mg/L in the springs at the base of the gravel terraces. Deeper groundwater interacting with underlying marine sequences increased the concentrations of SO(4), Cl, and Na up to 6000 mg/L and increased the alkalinity up to 923 mg/L CaCO(3) eq. in the coastal aquifer. These waters infiltrated into the tailings deposit at the shelf-tailings interface. Nonremediated tailings had a low-pH oxidation zone (pH 1-4) with significant accumulations of efflorescent salts (10-20 cm thick) at the surface because of upward capillary transport of metal cations in the arid climate. Remediated tailings were characterized by neutral pH and reducing conditions (pH ∼7, Eh ∼100 mV). As a result, most bivalent metals such as Cu, Zn, and Ni had very low concentrations (around 0.01 mg/L or below detection limit) because of reduction and sorption processes. In contrast, these reducing conditions increased the mobility of iron from two sources in this system: (1) The originally Fe(III)-rich oxidation zone, where Fe(III) was reduced during the remediation process and formed an Fe(II) plume, and (2) reductive dissolution of Fe(III) oxides present in the original shelf lithology formed an Fe-Mn plume at 10-m depth. These

Radon in indoor air. Health risk, measurement methods and remedial measures

International Nuclear Information System (INIS)

Strand, T.

1996-02-01

Radon in indoor air is the main source of ionizing radiation in Norway. The booklet contains a presentation of radon sources, measurement methods, indoor radon concentrations, action levels, health risk and remedial measures

Remediation challenges posed by the fate and transport properties of MTBE

International Nuclear Information System (INIS)

Day, M.J.

2002-01-01

Releases of fuel from underground tank systems have been a major source of groundwater contamination for several decades. The fate and transport characteristics of fuel components significantly influence the potential risk to groundwater supplies and the methodologies to manage and remediate contamination at fuel release sites. The recognition that MTBE can be more mobile in groundwater systems than other components of oxygenated fuels has put an increased emphasis on early detection and response to fuel leaks and spills. Remediation of oxygenated fuel releases usually follows a sequence of tasks: receptor protection, source control, residual and dissolved phase remediation, and monitored natural attenuation. Good characterization of hydrogeological and geochemical conditions is required because understanding the fate and transport of fuel components is critical to developing an appropriate management plan and an efficient remediation program. Understanding the specific site conditions allows appropriate selection and sequencing of remedial technologies. The physical and chemical characteristics of MTBE can result in a higher mobility in the subsurface, compared with the BTEX components of a gasoline release. These same characteristics make MTBE more readily extractable from the subsurface compared with BTEX. There is an impression that remediating gasoline releases containing MTBE requires costly, specialized technologies compared with those employed to deal with non-oxygenated fuel releases. However, the characteristics of MTBE are well suited to traditional, physical remedial approaches that have proven to be effective with the other components of gasoline. Technologies such as groundwater extraction, soil vapor extraction (SVE), and thermal desorption work exceptionally well with MTBE due to its low adsorptive and high vapor pressure characteristics. Similarly, recent studies have demonstrated that MTBE is biodegradable under a wide variety of conditions

Seismic source zone characterization for the seismic hazard assessment project PEGASOS by the Expert Group 2 (EG1b)

International Nuclear Information System (INIS)

Burkhard, M.; Gruenthal, G.

2009-01-01

A comprehensive study of the seismic hazard related to the four NNP sites in NW Switzerland was performed within the project PEGASOS. To account for the epistemic uncertainties involved in the process of the characterization of seismic source zones in the frame of probabilistic seismic hazard assessments, four different expert teams have developed and defended their models in the frame of an intensive elicitation process. Here, the results of one out of four expert groups are presented. The model of this team is based first of all on considerations regarding the large scale tectonics in the context of the Alpine collision, and neotectonic constraints for defining seismic source zones. This leads to a large scale subdivision based on the structural 'architectural' considerations with little input from the present seismicity. Each of the eight large zones was characterized by the style of present-day faulting, fault orientation, and hypo central depth distribution. A further subdivision of the larger zones is performed based on information provided by the seismicity patterns. 58 small source zones have been defined in this way, each of them characterized by the available tectonic constrains, as well as the pros and cons of different existing geologic views connected to them. Of special concern in this respect were the discussion regarding thin skinned vs. thick skinned tectonics, the tectonic origin of the 1356 Basel earthquake, the role of the Permo-Carboniferous graben structures, and finally the seismogenic orientation of faults with respect to the recent crustal stress field. The uncertainties connected to the delimitations of the small source zones have been handled in form of their regrouping, formalized by the logic tree technique. The maximum magnitudes were estimated as discretized probability distribution functions. After de-clustering the used ECOS earthquake catalogue and an analysis of data completeness as a function of time the parameters of the

Remedial action and waste disposal project -- 100-DR-1 remedial action readiness assessment report

International Nuclear Information System (INIS)

April, J.G.; Ard, J.A.; Corpuz, F.M.; DeMers, S.K.; Donahoe, R.L.; Frank, J.M.; Hobbs, B.J.; Roeck, F.V.

1997-02-01

This readiness assessment report presents the results of the project readiness assessment for the 100-DR-1 source sites remediation. The assessment was conducted at the conclusion of a series of project activities that began in August 1996. These activities included confirming the completion of project-specific procedures, training of staff, obtaining support equipment, receipt of subcontractor submittals, and mobilization and construction of site support systems

Technical Guidance Manual: Contaminant Flux Reduction Barriers for Managing Difficult-to-Treat Source Zones in Unconsolidated Media

Science.gov (United States)

2017-06-20

zone, the site must be:  Comprised of unconsolidated material (gravel, sand, silt, clay )  Have access around the source zone to building the...lower low permeability unit such as a clay to prevent up flow  For accessing the lower cost silica gel grouting technology, the hydraulic...hydraulic conductivity with sodium silicate grout.” (page 4-20).  Viscosities of typical grouts (Powers Figure 22.10)  Typical properties of Sodium

Guidelines for Remediation Strategies to Reduce the Radiological Consequences of Environmental Contamination

Energy Technology Data Exchange (ETDEWEB)

Fesenko, S; Howard, B J [eds.

2012-11-15

There are many areas around the world contaminated with radioactive substances which may require remediation. The source of contamination with radionuclides varies; the most important sources include nuclear testing, radiation accidents and inadequate waste disposal practices. Contamination at such sites may present a risk to humans and the environment. Therefore, issues related to remediation of such sites are potentially of concern for both the general public and a wide variety of stakeholders. In response to the needs of its Member States, the IAEA has published many books covering different aspects of remediation of contaminated environments. These books range from safety fundamentals and safety requirements to technical publications describing remedial technologies. Almost all of the publications 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 publication that was a joint undertaking by the IAEA and the Food and Agriculture Organization of the United Nations (FAO) related to accidents entitled Guidelines for Agricultural Countermeasures Following an Accidental Release of Radionuclides, Technical Reports Series No. 363 (1994) (TRS 363). This publication has constituted a major source of information over many years for staff of authorities providing environmental remediation planning after accidents. TRS 363 focused mainly on agricultural management options following an accidental release of radionuclides; remedial actions for other environments and other practices were not considered. Since the publication of TRS 363, there has been a considerable increase in relevant information. Given the importance of Chernobyl and other accidents, there have been a considerable number of IAEA activities devoted to the remediation of radiation accidents since 1994. Many

Guidelines for Remediation Strategies to Reduce the Radiological Consequences of Environmental Contamination

International Nuclear Information System (INIS)

Fesenko, S.; Howard, B.J.

2012-01-01

There are many areas around the world contaminated with radioactive substances which may require remediation. The source of contamination with radionuclides varies; the most important sources include nuclear testing, radiation accidents and inadequate waste disposal practices. Contamination at such sites may present a risk to humans and the environment. Therefore, issues related to remediation of such sites are potentially of concern for both the general public and a wide variety of stakeholders. In response to the needs of its Member States, the IAEA has published many books covering different aspects of remediation of contaminated environments. These books range from safety fundamentals and safety requirements to technical publications describing remedial technologies. Almost all of the publications 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 publication that was a joint undertaking by the IAEA and the Food and Agriculture Organization of the United Nations (FAO) related to accidents entitled Guidelines for Agricultural Countermeasures Following an Accidental Release of Radionuclides, Technical Reports Series No. 363 (1994) (TRS 363). This publication has constituted a major source of information over many years for staff of authorities providing environmental remediation planning after accidents. TRS 363 focused mainly on agricultural management options following an accidental release of radionuclides; remedial actions for other environments and other practices were not considered. Since the publication of TRS 363, there has been a considerable increase in relevant information. Given the importance of Chernobyl and other accidents, there have been a considerable number of IAEA activities devoted to the remediation of radiation accidents since 1994. Many

Bioremediation of RDX in the vadose zone beneath the Pantex Plant

Energy Technology Data Exchange (ETDEWEB)

Shull, T.L.; Speitel, G.E. Jr.; McKinney, D.C. [Univ. of Texas, Austin, TX (United States). Dept. of Civil Engineering

1999-01-01

The presence of dissolved high explosives (HE), in particular RDX and HMX, is well documented in the perched aquifer beneath the Pantex Plant, but the distribution of HE in the vadose zone has not yet been well defined. Although current remediation activities focus on the contamination in the perched aquifer, eventually regulatory concern is likely to turn to the residual contamination in the vadose zone. Sources of HE include the infiltration of past wastewater discharges from several HE-processing facilities through the ditch drainage system and leachate from former Landfill 3. With limited existing data on the HE distribution in the vadose zone and without preventive action, it must be assumed that residual HE could be leached into infiltrating water, providing a continuing supply of contamination to the perched aquifer. The purpose of this project was to more closely examine the fate and transport of HE in the vadose zone through mathematical modeling and laboratory experimentation. In particular, this report focuses on biodegradation as one possible fate of HE. Biodegradation of RDX in the vadose zone was studied because it is both present in highest concentration and is likely to be of the greatest regulatory concern. This study had several objectives: determine if indigenous soil organisms are capable of RDX biodegradation; determine the impact of electron acceptor availability and nutrient addition on RDX biodegradation; determine the extent of RDX mineralization (i.e., conversion to inorganic carbon) during biodegradation; and estimate the kinetics of RDX biodegradation to provide information for mathematical modeling of fate and transport.

Remediation of Oil-Contaminated Soil in Greenland

DEFF Research Database (Denmark)

Fritt-Rasmussen, Janne; Jensen, Pernille Erland

2013-01-01

This paper present the recent research conducted at the Arctic Technology Centre, where different solutions for remediation of excavated oil contaminated soil in Greenlandic towns were tested. In the first work, soil polluted by light oil was treated with two different nutrient sources (substrate...

Natural bioventing remediation from tidal wave action at a field site

International Nuclear Information System (INIS)

Kampbell, D.H.; Kittel, J.A.

1996-01-01

A remediation research study has been implemented at a jet fuel spill site on an island airport. A buried pipeline fracture several years ago resulted in a fuel spill exceeding 160,000 gallons. The site hydrogeology is a fragmented coral matrix with fresh water overlying more dense salt water. Water table fluctuations of about two feet occur once every twelve hours from tidal action. The research approach being pursued is to recover free-phase floating petroleum liquid using vacuum-mediated subsurface skimming wells. The vacuum will create an active vadose zone aeration to enhance aerobic biodegradation processes and vaporization of fuel. Once the floating fuel is removed, a natural bioventing action caused by tidal oscillations will complete remediation of the spill site

Active-to-Passive Environmental Cleanup Transition Strategies - 13220

International Nuclear Information System (INIS)

Gaughan, Thomas F.; Aylward, Robert S.; Denham, Miles E.; Looney, Brian B.; Whitaker, Wade C.; Mills, Gary L.

2013-01-01

The Savannah River Site uses a graded approach to environmental cleanup. The selection of groundwater and vadose zone remediation technologies for a specific contamination area is based on the size, contaminant type, contaminant concentration, and configuration of the plume. These attributes are the result of the nature and mass of the source of contamination and the subsurface characteristics in the area of the plume. Many large plumes consist of several zones that are most efficiently addressed with separate complementary corrective action/remedial technologies. The highest concentrations of contaminants are found in the source zone. The most robust, high mass removal technologies are often best suited for remediation of the source zone. In the primary plume zone, active remedies, such as pump-and-treat, may be necessary to remove contaminants and exert hydraulic control of the plume. In the dilute fringe zone, contaminants are generally lower in concentration and can often be treated with passive techniques. A key determination in achieving an acceptable and cost-effective end state for a given waste unit is when to transition from an active treatment system to a more passive or natural approach (e.g., monitored natural attenuation or enhanced attenuation). This paper will discuss the considerations for such a transition as well as provide examples of successful transitions at the Savannah River Site. (authors)

A remediation performance model for enhanced metabolic reductive dechlorination of chloroethenes in fractured clay till

Science.gov (United States)

Manoli, Gabriele; Chambon, Julie C.; Bjerg, Poul L.; Scheutz, Charlotte; Binning, Philip J.; Broholm, Mette M.

2012-04-01

A numerical model of metabolic reductive dechlorination is used to describe the performance of enhanced bioremediation in fractured clay till. The model is developed to simulate field observations of a full scale bioremediation scheme in a fractured clay till and thereby to assess remediation efficiency and timeframe. A relatively simple approach is used to link the fermentation of the electron donor soybean oil to the sequential dechlorination of trichloroethene (TCE) while considering redox conditions and the heterogeneous clay till system (clay till matrix, fractures and sand stringers). The model is tested on lab batch experiments and applied to describe sediment core samples from a TCE-contaminated site. Model simulations compare favorably to field observations and demonstrate that dechlorination may be limited to narrow bioactive zones in the clay matrix around fractures and sand stringers. Field scale simulations show that the injected donor is expected to be depleted after 5 years, and that without donor re-injection contaminant rebound will occur in the high permeability zones and the mass removal will stall at 18%. Long remediation timeframes, if dechlorination is limited to narrow bioactive zones, and the need for additional donor injections to maintain dechlorination activity may limit the efficiency of ERD in low-permeability media. Future work should address the dynamics of the bioactive zones, which is essential to understand for predictions of long term mass removal.

Integrated Field, Laboratory, and Modeling Studies to Determine the Effects of Linked Microbial and Physical Spatial Heterogeneity on Engineered Vadose Zone Bioremediation

Energy Technology Data Exchange (ETDEWEB)

Fred Brokman; John Selker; Mark Rockhold

2004-01-26

While numerous techniques exist for remediation of contaminant plumes in groundwater or near the soil surface, remediation methods in the deep vadose zone are less established due to complex transport dynamics and sparse microbial populations. There is a lack of knowledge on how physical and hydrologic features of the vadose zone control microbial growth and colonization in response to nutrient delivery during bioremediation. Yet pollution in the vadose zone poses a serious threat to the groundwater resources lying deeper in the sediment. While the contaminants may be slowly degraded by native microbial communities, microbial degradation rates rarely keep pace with the spread of the pollutant. It is crucial to increase indigenous microbial degradation in the vadose zone to combat groundwater contamination.

Integrated Field, Laboratory, and Modeling Studies to Determine the Effects of Linked Microbial and Physical Spatial Heterogeneity on Engineered Vadose Zone Bioremediation

Energy Technology Data Exchange (ETDEWEB)

Brockman, Fred J.; Selker, John S.; Rockhold, Mark L.

2004-10-31

Executive Summary - While numerous techniques exist for remediation of contaminant plumes in groundwater or near the soil surface, remediation methods in the deep vadose zone are less established due to complex transport dynamics and sparse microbial populations. There is a lack of knowledge on how physical and hydrologic features of the vadose zone control microbial growth and colonization in response to nutrient delivery during bioremediation. Yet pollution in the vadose zone poses a serious threat to the groundwater resources lying deeper in the sediment. While the contaminants may be slowly degraded by native microbial communities, microbial degradation rates rarely keep pace with the spread of the pollutant. It is crucial to increase indigenous microbial degradation in the vadose zone to combat groundwater contamination...

Vadose Zone Hydrogeology Data Package for Hanford Assessments

Energy Technology Data Exchange (ETDEWEB)

Last, George V.; Freeman, Eugene J.; Cantrell, Kirk J.; Fayer, Michael J.; Gee, Glendon W.; Nichols, William E.; Bjornstad, Bruce N.; Horton, Duane G.

2006-06-01

This data package documents the technical basis for selecting physical and geochemical parameters and input values that will be used in vadose zone modeling for Hanford assessments. This work was originally conducted as part of the Characterization of Systems Task of the Groundwater Remediation Project managed by Fluor Hanford, Inc., Richland, Washington, and revised as part of the Characterization of Systems Project managed by the Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy, Richland Operations Office (DOE-RL). This data package describes the geologic framework, the physical, hydrologic, and contaminant transport properties of the geologic materials, and deep drainage (i.e., recharge) estimates, and builds on the general framework developed for the initial assessment conducted using the System Assessment Capability (SAC) (Bryce et al. 2002). The general approach for this work was to update and provide incremental improvements over the previous SAC data package completed in 2001. As with the previous SAC data package, much of the data and interpreted information were extracted from existing documents and databases. Every attempt was made to provide traceability to the original source(s) of the data or interpretations.

40 CFR 258.57 - Selection of remedy.

Science.gov (United States)

2010-07-01

... which may offer significant advantages over already available technologies in terms of effectiveness... environment from exposure to contamination prior to completion of the remedy; (6) Resource value of the... substances that have originated from a source other than a MSWLF unit and those substances are present in...

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

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

Remedial pulse programme for the production of monoenergetic ion beams of low energy

International Nuclear Information System (INIS)

Olubuyide, O.A.

1975-01-01

The technique involves an extension of sequential pulse techniques. An ion swarm is produced in a conventional mass-spectrometer ion source by a short electron beam pulse. Immediately, this swarm is accelerated impulsively by a short high voltage pulse on the repeller. The principal disadvantage of impulsive acceleration is that the final energy distribution of the ion swarm is broad especially at the lowest energies. At some instant during the passage of the ion swarm across the chamber second pulse is applied to the repeller--a ''remedial'' pulse which will accelerate the ions throughout the remainder of their passage and whose amplitude will be time-dependent. Slower ions must travel a greater distance in this ''remedial'' field than faster ions and will experience a proportionately greater increase in velocity from it. In this way, the remedial pulse can cause all the ions to acquire the same velocity at the exit slit. A limited experimental investigation has been made to examine the application of the proposed remedial pulse technique to existing ion sources. Application of the remedial pulse to impulsively-accelerated ion swarms reduced the energy distribution in the manner predicted by the theory but the quantitative reduction measured experimentally--a factor of approximately 2--was substantially less than the theoretical prediction of a factor of approximately 4. The limitations were characterized and a means of overcoming them was suggested in a new ion source of improved design. (Diss. Abstr. Int., B)

Integrated program management for major nuclear decommissioning and environmental remediation projects - 59068

International Nuclear Information System (INIS)

Lehew, John

2012-01-01

Document available in abstract form only. Full text of publication follows: CH2M HILL Plateau Remediation Company (CH2M HILL) is the U.S. Department of Energy's (DOE) contractor responsible for the safe, environmental cleanup of the Hanford Sites Central Plateau, sections of the Columbia River Corridor and the Hanford Reach National Monument. The 586-square-mile Hanford Site is located along the Columbia River in southeastern Washington, U.S.A. A plutonium production complex, housing the largest volume of radioactive and contaminated waste in the nation, with nine nuclear reactors and associated processing facilities, Hanford played a pivotal role in the nation's defense for more than 40 years, beginning in the 1940's with the Manhattan Project. Today, under the direction of the DOE, Hanford is engaged in one of the world's largest environmental cleanup project. The Plateau Remediation Contract is a 10-year project paving the way for closure of the Hanford Site. The site through its location, climate, geology and proximity to the Columbia River in combination with the results of past nuclear operations presents a highly complex environmental remediation challenge. The complexity is not only due to the technical issues associated with decommissioning nuclear facilities, remediating soil contamination sites, dispositioning legacy waste and fuel materials and integrating these with the deep vadose zone and groundwater remediation

Resistivity and self-potential tomography applied to groundwater remediation and contaminant plumes: Sandbox and field experiments

Science.gov (United States)

Mao, D.; Revil, A.; Hort, R. D.; Munakata-Marr, J.; Atekwana, E. A.; Kulessa, B.

2015-11-01

Geophysical methods can be used to remotely characterize contaminated sites and monitor in situ enhanced remediation processes. We have conducted one sandbox experiment and one contaminated field investigation to show the robustness of electrical resistivity tomography and self-potential (SP) tomography for these applications. In the sandbox experiment, we injected permanganate in a trichloroethylene (TCE)-contaminated environment under a constant hydraulic gradient. Inverted resistivity tomograms are able to track the evolution of the permanganate plume in agreement with visual observations made on the side of the tank. Self-potential measurements were also performed at the surface of the sandbox using non-polarizing Ag-AgCl electrodes. These data were inverted to obtain the source density distribution with and without the resistivity information. A compact horizontal dipole source located at the front of the plume was obtained from the inversion of these self-potential data. This current dipole may be related to the redox reaction occurring between TCE and permanganate and the strong concentration gradient at the front of the plume. We demonstrate that time-lapse self-potential signals can be used to track the kinetics of an advecting oxidizer plume with acceptable accuracy and, if needed, in real time, but are unable to completely resolve the shape of the plume. In the field investigation, a 3D resistivity tomography is used to characterize an organic contaminant plume (resistive domain) and an overlying zone of solid waste materials (conductive domain). After removing the influence of the streaming potential, the identified source current density had a magnitude of 0.5 A m-2. The strong source current density may be attributed to charge movement between the neighboring zones that encourage abiotic and microbially enhanced reduction and oxidation reactions. In both cases, the self-potential source current density is located in the area of strong resistivity

Prediction of Groundwater Quality Improvement Down-Gradient of In Situ Permeable Treatment Barriers and Fully-Remediated Source Zones. ESTCP Cost and Performance Report

National Research Council Canada - National Science Library

Johnson, Paul C; Carlson, Pamela M; Dahlen, Paul

2008-01-01

In situ permeable treatment barriers (PTB) are designed so that contaminated groundwater flows through an engineered treatment zone within which contaminants are eliminated or the concentrations are significantly reduced...

Surface water management at a mixed waste remediation site

International Nuclear Information System (INIS)

Schlotzhauer, D.S.; Warbritton, K.R.

1991-01-01

The Weldon Spring Remedial Action Project (WSSRAP) deals with chemical and radiological contaminants. MK-Ferguson Company is managing the project under contract with the US Department of Energy. Remedial activities include demolishing buildings, constructing material storage and staging areas, excavating and consolidating waste materials, and treating and disposing of the materials in a land disposal facility. Due to the excavation and construction required during remediation, a well-planned surface water management system is essential. Planning involves characterization of source areas and surface water transport mechanisms and identification of applicable regulations. System components include: erosion control sediment control, flow attenuation, and management of contaminated water. Combinations of these components may be utilized during actual construction and remediation to obtain optimum control. Monitoring is performed during implementation in order to assess the effectiveness of control measures. This management scheme provides for comprehensive management of surface water at this site by providing control and/or treatment to appropriate standards. Although some treatment methodologies for contaminated water are specific to site contaminants, this comprehensive program provides a management approach which is applicable to many remedial projects in order to minimize contaminant release and meet Clean Water Act requirements

Dynamics And Remediation Of Fine Textured Soils And Ground Water Contaminated With Salts And Chlorinated Organic Compounds

Science.gov (United States)

Murata, Alison; Naeth, M. Anne

2017-04-01

Soil and ground water are frequently contaminated by industrial activities, posing a potential risk to human and environmental health and limiting land use. Proper site management and remediation treatments can return contaminated areas to safe and useful states. Most remediation research focuses on single contaminants in coarse and medium textured soils. Contaminant mixtures are common and make remediation efforts complex due to differing chemical properties. Remediation in fine textured soils is difficult since their low hydraulic conductivities hinder addition of amendments into and removal of contaminated media out of the impacted zone. The objective of this research is to assess contaminant dynamics and potential remediation techniques for fine textured soil and ground water impacted by multiple contaminants in Edmonton, Alberta, Canada. The University of Alberta's Ellerslie Waste Management Facility was used to process liquid laboratory waste from 1972 to 2007. A waste water pond leak prior to 1984 resulted in salt and chlorinated organic compound contamination. An extensive annual ground water monitoring data set for the site is available since 1988. Analytical parameters include pH, electrical conductivity, major ions, volatile organic compounds, and metals. Data have been compared to Alberta Tier 1 Soil and Groundwater Remediation Guidelines to identify exceedances. The parameters of greatest concern, based on magnitude and frequency of detection, are electrical conductivity, sodium, chloride, chloroform, and dichloromethane. Spatial analyses of the data show that the contamination is focused in and down gradient of the former waste water pond. Temporal analyses show different trends depending on monitoring well location. Laboratory column experiments were used to assess leaching as a potential treatment for salt contamination in fine textured soils. Saturated hydraulic conductivity was measured for seven soils from two depth intervals with or without

Mercury contaminated sediment sites—An evaluation of remedial options

Energy Technology Data Exchange (ETDEWEB)

Randall, Paul M., E-mail: randall.paul@epa.gov [U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, 26 West Martin Luther King Drive, Cincinnati, OH 45268 (United States); Chattopadhyay, Sandip, E-mail: Sandip.Chattopadhyay@tetratech.com [Tetra Tech, Inc., 250 West Court Street, Suite 200W, Cincinnati, OH 45202 (United States)

2013-08-15

Mercury (Hg) is a naturally-occurring element that is ubiquitous in the aquatic environment. Though efforts have been made in recent years to decrease Hg emissions, historically-emitted Hg can be retained in the sediments of aquatic bodies where they may be slowly converted to methylmercury (MeHg). Consequently, Hg in historically-contaminated sediments can result in high levels of significant exposure for aquatic species, wildlife and human populations consuming fish. Even if source control of contaminated wastewater is achievable, it may take a very long time, perhaps decades, for Hg-contaminated aquatic systems to reach relatively safe Hg levels in both water and surface sediment naturally. It may take even longer if Hg is present at higher concentration levels in deep sediment. Hg contaminated sediment results from previous releases or ongoing contributions from sources that are difficult to identify. Due to human activities or physical, chemical, or biological processes (e.g. hydrodynamic flows, bioturbation, molecular diffusion, and chemical transformation), the buried Hg can be remobilized into the overlying water. Hg speciation in the water column and sediments critically affect the reactivity (i.e. conversion of inorganic Hg(II) to MeHg), transport, and its exposure to living organisms. Also, geochemical conditions affect the activity of methylating bacteria and its availability for methylation. This review paper discusses remedial considerations (e.g. key chemical factors in fate and transport of Hg, source characterization and control, environmental management procedures, remediation options, modeling tools) and includes practical case studies for cleaning up Hg-contaminated sediment sites. -- Highlights: ► Managing mercury-contaminated sediment sites are challenging to remediate. ► Remediation technologies are making a difference in managing these sites. ► Partitioning plays a dominant role in the distribution of mercury species. ► Mathematical

Bibliography on Chernobyl radioactivity impacts and remediation of forest ecosystems

Energy Technology Data Exchange (ETDEWEB)

Rennie, C.D.; Baweja, A.S.

1992-01-01

Bibliography on the Chernobyl nuclear accident pertaining to radiological sources, distribution of radioactivity, transport of radionuclides in aquatic and terrestrial ecosystems, and biological impacts/indicators. The second section lists references on remediation technologies at Bikini Atoll Islands. References include books and periodicals from Canada, the United States, and European sources.

Soil Contamination and Remediation Strategies. Current research and future challenge

Science.gov (United States)

Petruzzelli, G.

2012-04-01

eliminating the source of pollution, but also on blocking the pathways from contaminants to receptors or reducing the exposure to contaminants,. Future challenge integration of sustainability into remediation decision-making. Soil is not a waste! There is a growing interest in the clean up approaches that maintain soil quality after remediation treatments. This issue is of great importance in the U.S.A. where the EPA from 2009 is promoting innovative clean-up strategies (Green Remediation). Green remediation is defined as the practice of considering all environmental effects of remedy and incorporating options to maximize environmental benefit of cleanup actions . These remediation strategies restore contaminated sites to productive use with a great attention to the global environmental quality, including the preservation of soil functionality according to the following principles: use minimally invasive technologies; use passive energy technologies such as bioremediation and phytoremediation as primary remedies or finishing steps where possible and effective; minimize soil and habitat disturbance; minimize bioavailability of contaminants trough adequate contaminant source and plume control If we move from the current definition of remedial targets based on total concentrations, technologies with low impact on the environment can be utilized reducing the wrong choice to disposal soil in landfill destroying quickly a not renewable essential resource.

Biofilm formation and microbial community analysis of the simulated river bioreactor for contaminated source water remediation.

Science.gov (United States)

Xu, Xiang-Yang; Feng, Li-Juan; Zhu, Liang; Xu, Jing; Ding, Wei; Qi, Han-Ying

2012-06-01

The start-up pattern of biofilm remediation system affects the biofilm characteristics and operating performances. The objective of this study was to evaluate the performances of the contaminated source water remediation systems with different start-up patterns in view of the pollutants removal performances and microbial community succession. The operating performances of four lab-scale simulated river biofilm reactors were examined which employed different start-up methods (natural enrichment and artificial enhancement via discharging sediment with influent velocity gradient increase) and different bio-fillers (Elastic filler and AquaMats® ecobase). At the same time, the microbial communities of the bioreactors in different phases were analyzed by polymerase chain reaction, denaturing gradient gel electrophoresis, and sequencing. The pollutants removal performances became stable in the four reactors after 2 months' operation, with ammonia nitrogen and permanganate index (COD(Mn)) removal efficiencies of 84.41-94.21% and 69.66-76.60%, respectively. The biomass of mature biofilm was higher in the bioreactors by artificial enhancement than that by natural enrichment. Microbial community analysis indicated that elastic filler could enrich mature biofilm faster than AquaMats®. The heterotrophic bacteria diversity of biofilm decreased by artificial enhancement, which favored the ammonia-oxidizing bacteria (AOB) developing on the bio-fillers. Furthermore, Nitrosomonas- and Nitrosospira-like AOB coexisted in the biofilm, and Pseudomonas sp., Sphaerotilus sp., Janthinobacterium sp., Corynebacterium aurimucosum were dominant in the oligotrophic niche. Artificial enhancement via the combination of sediment discharging and influent velocity gradient increasing could enhance the biofilm formation and autotrophic AOB enrichment in oligotrophic niche.

REVIEW REPORT: BUILDING C-400 THERMAL TREATMENT 90 PERCENT REMEDIAL DESIGN REPORT AND SITE INVESTIGATION, PGDP, PADUCAH, KENTUCKY

International Nuclear Information System (INIS)

Looney, B; Jed Costanza, J; Eva Davis, E; Joe Rossabi, J; Lloyd Stewart, L; Hans Stroo, H

2007-01-01

On 9 April 2007, the U.S. Department of Energy (DOE) Headquarters, Office of Soil and Groundwater Remediation (EM-22) initiated an Independent Technical Review (ITR) of the 90% Remedial Design Report (RDR) and Site Investigation (RDSI) for thermal treatment of trichloroethylene (TCE) in the soil and groundwater in the vicinity of Building C-400 at the Paducah Gaseous Diffusion Plant (PGDP). The general ITR goals were to assess the technical adequacy of the 90% RDSI and provide recommendations sufficient for DOE to determine if modifications are warranted pertaining to the design, schedule, or cost of implementing the proposed design. The ultimate goal of the effort was to assist the DOE Paducah/Portsmouth Project Office (PPPO) and their contractor team in ''removing'' the TCE source zone located near the C-400 Building. This report provides the ITR findings and recommendations and supporting evaluations as needed to facilitate use of the recommendations. The ITR team supports the remedial action objective (RAO) at C-400 to reduce the TCE source area via subsurface Electrical Resistance Heating (ERH). Further, the ITR team commends PPPO, their contractor team, regulators, and stakeholders for the significant efforts taken in preparing the 90% RDR. To maximize TCE removal at the target source area, several themes emerge from the review which the ITR team believes should be considered and addressed before implementing the thermal treatment. These themes include the need for: (1) Accurate and site-specific models as the basis to verify the ERH design for full-scale implementation for this challenging hydrogeologic setting; (2) Flexible project implementation and operation to allow the project team to respond to observations and data collected during construction and operation; (3) Defensible performance metrics and monitoring, appropriate for ERH, to ensure sufficient and efficient clean-up; and (4) Comprehensive (creative and diverse) contingencies to address the

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

Radon impact at a remediated uranium mine site in Japan

International Nuclear Information System (INIS)

Ishimori, Yuu

2011-01-01

This paper mainly illustrates the radon impact of the closed uranium mine site remediated in 2007. The site remediated is the waste rock site located on the steep slope of a hill about 1.5 km upstream from a residential area along a main ravine. Major remedial action was to cover these waste rock yards with weathering granite soil. The radon flux density after remediation was intended to be 0.1 Bqm -2 s -1 in consideration with the natural background level around Ningyo-toge because there is no value of radon flux density regulated in Japan. Our action decreased the radon concentration in the site to natural background level, approximately from 10 to 40 Bqm -3 , although relatively high concentration in excess of 100 Bqm -3 was observed before remediation. On the other hand, our action did not decrease the radon concentrations around the site in general. This fact proved that the limited source such as waste rocks affected the radon concentrations at neighboring area only. The similar tendencies were also observed in other environmental data such as radon progeny concentrations. In conclusion, these findings proved that our remedial action was successful against radon. This fact will lead to more reasonable action plans for other closed mine sites. (author)

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

Soil sorting, new approach to site remediation management

International Nuclear Information System (INIS)

Bramlitt, E.T.; Woods, J.A.; Dillon, M.J.

1996-01-01

Soil sorting is the technology which conveys soil beneath contaminant detectors and, based on contaminant signal, automatically toggles a gate at the conveyor end to send soil with contamination above a guideline to a separate location from soil which meets the guideline. The technology was perfected for remediation of sites having soils with radioactive contamination, but it is applicable to other contaminants when instrumental methods exist for rapid contaminant detection at levels of concern. This paper examines the three methods for quantifying contamination in soil in support of site remediation management. Examples are discussed where the primary contaminant is plutonium, a radioactive substance and source of nuclear energy which can be hazardous to health when in the environment without controls. Field survey instruments are very sensitive to plutonium and can detect it in soil at levels below a part per billion, and there are a variety of soils which have been contaminated by plutonium and thoroughly investigated. The lessons learned with plutonium are applicable to other types of contaminants and site remediations. The paper concludes that soil sorting can be the most cost effective approach to site remediation, and it leads to the best overall cleanup

Environmental Restoration Remedial Action quality assurance requirements document

International Nuclear Information System (INIS)

1991-01-01

This document defines the quality assurance requirements for the US Department of Energy-Richland Operations Office Environmental Restoration Remedial Action program at the Hanford Site. The Environmental Restoration Remedial Action program implements significant commitments made by the US Department of Energy in the Hanford Federal Facility Agreement and Consent Order entered into with the Washington State Department of Ecology and the US Environmental Protection Agency. This document combines quality assurance requirements from various source documents into one set of requirements for use by the US Department of Energy-Richland Operations Office and other Environmental Restoration Remedial Action program participants. This document will serve as the basis for developing Quality Assurance Program Plans and implementing procedures by the participants. The requirements of this document will be applied to activities affecting quality, using a graded approach based on the importance of the item, service, or activity to the program objectives. The Quality Assurance Program that will be established using this document as the basis, together with other program and technical documents, form an integrated management control system for conducting the Environmental Restoration Remedial Action program activities in a manner that provides safety and protects the environment and public health

Pre- and post-remediation characterization of acid-generating fluvial tailings material

Science.gov (United States)

Smith, Kathleen S.; Walton-Day, Katherine; Hoal, Karin O.; Driscoll, Rhonda L.; Pietersen, K.

2012-01-01

The upper Arkansas River south of Leadville, Colorado, USA, contains deposits of fluvial tailings from historical mining operations in the Leadville area. These deposits are potential non-point sources of acid and metal contamination to surface- and groundwater systems. We are investigating a site that recently underwent in situ remediation treatment with lime, fertilizer, and compost. Pre- and post-remediation fluvial tailings material was collected from a variety of depths to examine changes in mineralogy, acid generation, and extractable nutrients. Results indicate sufficient nutrient availability in the post-remediation near-surface material, but pyrite and acid generation persist below the depth of lime and fertilizer addition. Mineralogical characterization performed using semi-quantitative X-ray diffraction and quantitative SEM-based micro-mineralogy (Mineral Liberation Analysis, MLA) reveal formation of gypsum, jarosite, and complex coatings surrounding mineral grains in post-remediation samples.

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

Preliminary remediation goals for ecological endpoints

International Nuclear Information System (INIS)

Efroymson, R.A.; Suter, G.W. II.

1995-09-01

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 US 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

Remediation of copper in vineyards – A mini review

International Nuclear Information System (INIS)

Mackie, K.A.; Müller, T.; Kandeler, E.

2012-01-01

Viticulturists use copper fungicide to combat Downy Mildew. Copper, a non-degradable heavy metal, can accumulate in soil or leach into water sources. Its accumulation in topsoil has impacted micro and macro organisms, spurring scientists to research in situ copper removal methods. Recent publications suggest that microorganism assisted phytoextraction, using plants and bacteria to actively extract copper, is most promising. As vineyards represent moderately polluted sites this technique has great potential. Active plant extraction and chelate assisted remediation extract too little copper or risk leaching, respectively. However, despite interesting pot experiment results using microorganism assisted phytoextraction, it remains a challenge to find plants that primarily accumulate copper in their shoots, a necessity in vineyards where whole plant removal would be time consuming and financially cumbersome. Vineyard remediation requires a holistic approach including sustainable soil management, proper plant selection, increasing biodiversity and microorganisms. - Highlights: ► We describe copper distribution and availability in vineyards. ► We explain the environmental impact of copper on organisms, plants and processes. ► We detail possible remediation methods within vineyards. ► Microbially assisted phytoremediation is the most promising remediation method. ► A solution requires an interdisciplinary approach between plants, soil and vines. - This review is significant because it highlights prospective remediation methods usable in copper contaminated vineyards.

Efficiency of modified chemical remediation techniques for soil contaminated by organochlorine pesticides

Science.gov (United States)

Correa-Torres, S. N.; Kopytko, M.; Avila, S.

2016-07-01

This study reports the optimization of innovation chemical techniques in order to improve the remediation of soils contaminated with organochloride pesticides. The techniques used for remediation were dehalogenation and chemical oxidation in soil contaminated by pesticides. These techniques were applied sequentially and combined to evaluate the design optimize the concentration and contact time variables. The soil of this study was collect in cotton crop zone in Agustin Codazzi municipality, Colombia, and its physical properties was measure. The modified dehalogenation technique of EPA was applied on the contaminated soil by adding Sodium Bicarbonate solution at different concentrations and rates during 4, 7 and 14 days, subsequently oxidation technique was implemented by applying a solution of KMnO4 at different concentration and reaction times. Organochlorine were detected by Gas Chromatography analysis coupled Mass Spectrometry and its removals were between 85.4- 90.0% of compounds such as 4, 4’-DDT, 4,4’-DDD, 4,4-DDE, trans-Clordane y Endrin. These results demonstrate that the technique of dehalogenation with oxidation chemistry can be used for remediation soils contaminated by organochloride pesticides.

Electrokinetic remediation of anionic contamination from unsaturated soil: Field application

International Nuclear Information System (INIS)

Lindgren, E.R.; Mattson, E.D.

1995-01-01

Electrokinetic remediation is an in situ technique under development at Sandia National Laboratories for removal of ionic contaminants from soil. While to date most other studies of this technique have focused on saturated soils, usually clays, the work at Sandia has been to extend the process to unsaturated sandy soils typical of arid regions. The impetus for this study is a chromate plume located beneath an old Sandia chemical waste landfill. Working in unsaturated soils is complicated by moisture control requirements, both to prevent undesired hydraulic transport of contamination outside the treatment zone and to optimize soil properties for efficient electrokinetic remediation. Two field tests will be discussed. First, a field test in clean soil is in progress to demonstrate moisture control with the Sandia electrode system. The second field demonstration, planned to begin the Fall of 1995, involves chromate removal from a in a chemical waste landfill

Field-scale study of the influence of differing remediation strategies on trace metal geochemistry in metal mine tailings from the Irish Midlands.

Science.gov (United States)

Perkins, William T; Bird, Graham; Jacobs, Suzanne R; Devoy, Cora

2016-03-01

Mine tailings represent a globally significant source of potentially harmful elements (PHEs) to the environment. The management of large volumes of mine tailings represents a major challenge to the mining industry and environmental managers. This field-scale study evaluates the impact of two highly contrasting remediation approaches to the management and stabilisation of mine tailings. The geochemistry of the tailings, overlying amendment layers and vegetation are examined in the light of the different management approaches. Pseudo-total As, Cd and Pb concentrations and solid-state partitioning (speciation), determined via sequential extraction, were established for two Tailings Management Facilities (TMFs) in Ireland subjected to the following: (1) a 'walk-away' approach (Silvermines) and (2) application of an amendment layer (Galmoy). PHE concentrations in roots and herbage of grasses growing on the TMFs were also determined. Results identify very different PHE concentration profiles with depth through the TMFs and the impact of remediation approach on concentrations and their potential bioavailability in the rooting zone of grass species. Data also highlight the importance of choice of grass species in remediation approaches and the benefits of relatively shallow-rooting Agrostis capillaris and Festuca rubra varieties. In addition, data from the Galmoy TMF indicate the importance of regional soil geochemistry for interpreting the influence of the PHE geochemistry of capping and amendment layers applied to mine tailings.

A model for homeopathic remedy effects: low dose nanoparticles, allostatic cross-adaptation, and time-dependent sensitization in a complex adaptive system

Directory of Open Access Journals (Sweden)

Bell Iris R

2012-10-01

Full Text Available Abstract Background This paper proposes a novel model for homeopathic remedy action on living systems. Research indicates that homeopathic remedies (a contain measurable source and silica nanoparticles heterogeneously dispersed in colloidal solution; (b act by modulating biological function of the allostatic stress response network (c evoke biphasic actions on living systems via organism-dependent adaptive and endogenously amplified effects; (d improve systemic resilience. Discussion The proposed active components of homeopathic remedies are nanoparticles of source substance in water-based colloidal solution, not bulk-form drugs. Nanoparticles have unique biological and physico-chemical properties, including increased catalytic reactivity, protein and DNA adsorption, bioavailability, dose-sparing, electromagnetic, and quantum effects different from bulk-form materials. Trituration and/or liquid succussions during classical remedy preparation create “top-down” nanostructures. Plants can biosynthesize remedy-templated silica nanostructures. Nanoparticles stimulate hormesis, a beneficial low-dose adaptive response. Homeopathic remedies prescribed in low doses spaced intermittently over time act as biological signals that stimulate the organism’s allostatic biological stress response network, evoking nonlinear modulatory, self-organizing change. Potential mechanisms include time-dependent sensitization (TDS, a type of adaptive plasticity/metaplasticity involving progressive amplification of host responses, which reverse direction and oscillate at physiological limits. To mobilize hormesis and TDS, the remedy must be appraised as a salient, but low level, novel threat, stressor, or homeostatic disruption for the whole organism. Silica nanoparticles adsorb remedy source and amplify effects. Properly-timed remedy dosing elicits disease-primed compensatory reversal in direction of maladaptive dynamics of the allostatic network, thus promoting

The Rush to Remediate: Long Term Performance Favors Passive Systems at SRS

International Nuclear Information System (INIS)

Hoffman, D.; Cauthen, K.; Beul, R. R.

2003-01-01

The purpose of this paper is to describe the long-term performance of groundwater remediation systems at SRS and compare active versus passive systems. The presentation will focus on the limited effectiveness of active pump and treat systems and share the experience with more passive and natural systems such as soil vapor extraction, barometric pumping, bioremediation, and phytoremediation. Three remediation projects are presented. In each case the waste source is capped with clay or synthetic barriers; however, extensive groundwater contamination remains. The first project features the cleanup of the largest plume in the United States. The second project entails solvent and vinyl chloride remediation of groundwater beneath a hazardous waste landfill. The third project discusses tritium containment from a 160-acre radioactive waste disposal area. Special emphasis is placed on performance data from alternate technology cleanup. The goals are to share remediation data, successes and lessons learned, while making a case for passive systems use in groundwater remediation

Cost-efficient remediation of an upstream oilfield battery site

Energy Technology Data Exchange (ETDEWEB)

Siebert, L.D. [Imperial Oil Resources Canada, Calgary, AB (Canada); Bedard, G.; Pouliot, M.; Soucy, F.; Faucher, C.; Corbin, R. [Biogenie Inc., Quebec City, PQ (Canada)

2003-07-01

The soil at an oilfield battery site, located 18 kilometres (km) northwest of Devon, Alberta has been contaminated with crude oil and salt, following years of operation. Surrounding the site is flat farmland intended for future agricultural production. A remedial program aimed at complying with Tier I criteria of the Alberta Soil and Water Quality Guidelines for Hydrocarbons at Upstream Oil and Gas Facilities (ASWQG) of Alberta Environment, was developed and implemented. Characterization of the site was carried out in 1997 to delineate a salt plume, followed by a second sampling campaign in 1999, which all together revealed three impacted areas. A supplementary characterization was performed in 2001 by Biogenie in an effort to better determine the nature and level of petroleum contamination and more accurately evaluate the volume of contaminated soil. A three-dimensional Visualization software integrating a Kriging geostatistical model was used for this purpose. The results indicated that an estimated 8,800 cubic metres of contaminated soil would need to be excavated and treated. The next phase involved an evaluation of the various remedial options, which was accomplished using a biotreatability study. The remediation program selected involved the excavation of the contaminated soil and segregation of source material, the ex-situ Biopile treatment of the source material to meet Class II landfill criteria, and the ex-situ Biopile treatment of the contaminated soil followed by its use as backfill on site. The biotreatability study proved to be a strategic tool in the remediation effort. 1 tab., 2 figs.

Cascadia Subduction Zone Earthquake Source Spectra from an Array of Arrays

Science.gov (United States)

Gomberg, J. S.; Vidale, J. E.

2011-12-01

suggests it is more likely that variation in attenuation modulates the spectra. Because the variations in apparent source spectra correlate well with source location, but poorly with receiver location, we infer that near-source attenuation differences likely are much more significant. We conclude that the conventional wisdom may require some revision - that near-source propagation effects may be responsible for some fraction of what has hitherto been attributed to source processes. Moreover, our results further suggest that subduction zone earthquakes do not separate neatly into 'slow' and 'fast' classes, but likely span a continuum.

Remediation of Uranium in the Hanford Vadose Zone Using Ammonia Gas: FY 2010 Laboratory-Scale Experiments

Energy Technology Data Exchange (ETDEWEB)

Szecsody, James E.; Truex, Michael J.; Zhong, Lirong; Qafoku, Nikolla; Williams, Mark D.; McKinley, James P.; Wang, Zheming; Bargar, John; Faurie, Danielle K.; Resch, Charles T.; Phillips, Jerry L.

2010-12-01

This investigation is focused on refining an in situ technology for vadose zone remediation of uranium by the addition of ammonia (NH3) gas. Objectives are to: a) refine the technique of ammonia gas treatment of low water content sediments to minimize uranium mobility by changing uranium surface phases (or coat surface phases), b) identify the geochemical changes in uranium surface phases during ammonia gas treatment, c) identify broader geochemical changes that occur in sediment during ammonia gas treatment, and d) predict and test injection of ammonia gas for intermediate-scale systems to identify process interactions that occur at a larger scale and could impact field scale implementation.Overall, NH3 gas treatment of low-water content sediments appears quite effective at decreasing aqueous, adsorbed uranium concentrations. The NH3 gas treatment is also fairly effective for decreasing the mobility of U-carbonate coprecipitates, but shows mixed success for U present in Na-boltwoodite. There are some changes in U-carbonate surface phases that were identified by surface phase analysis, but no changes observed for Na-boltwoodite. It is likely that dissolution of sediment minerals (predominantly montmorillonite, muscovite, kaolinite) under the alkaline conditions created and subsequent precipitation as the pH returns to natural conditions coat some of the uranium surface phases, although a greater understanding of these processes is needed to predict the long term impact on uranium mobility. Injection of NH3 gas into sediments at low water content (1% to 16% water content) can effectively treat a large area without water addition, so there is little uranium mobilization (i.e., transport over cm or larger scale) during the injection phase.

Remediation of Uranium in the Hanford Vadose Zone Using Ammonia Gas: FY 2010 Laboratory-Scale Experiments

International Nuclear Information System (INIS)

Szecsody, James E.; Truex, Michael J.; Zhong, Lirong; Qafoku, Nikolla; Williams, Mark D.; McKinley, James P.; Wang, Zheming; Bargar, John; Faurie, Danielle K.; Resch, Charles T.; Phillips, Jerry L.

2010-01-01

This investigation is focused on refining an in situ technology for vadose zone remediation of uranium by the addition of ammonia (NH3) gas. Objectives are to: (a) refine the technique of ammonia gas treatment of low water content sediments to minimize uranium mobility by changing uranium surface phases (or coat surface phases), (b) identify the geochemical changes in uranium surface phases during ammonia gas treatment, (c) identify broader geochemical changes that occur in sediment during ammonia gas treatment, and (d) predict and test injection of ammonia gas for intermediate-scale systems to identify process interactions that occur at a larger scale and could impact field scale implementation. Overall, NH3 gas treatment of low-water content sediments appears quite effective at decreasing aqueous, adsorbed uranium concentrations. The NH3 gas treatment is also fairly effective for decreasing the mobility of U-carbonate coprecipitates, but shows mixed success for U present in Na-boltwoodite. There are some changes in U-carbonate surface phases that were identified by surface phase analysis, but no changes observed for Na-boltwoodite. It is likely that dissolution of sediment minerals (predominantly montmorillonite, muscovite, kaolinite) under the alkaline conditions created and subsequent precipitation as the pH returns to natural conditions coat some of the uranium surface phases, although a greater understanding of these processes is needed to predict the long term impact on uranium mobility. Injection of NH3 gas into sediments at low water content (1% to 16% water content) can effectively treat a large area without water addition, so there is little uranium mobilization (i.e., transport over cm or larger scale) during the injection phase.

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

site history and data and organizing the information into a conceptual model and findings to assist in evaluating the potential of alternative remediation technologies. Examples of the key conceptual findings of the EM-32 review team were: (1) The Gallia represents the most practical target for deployment of in situ remediation treatment reagents - injection/extraction focused in this zone would provide maximum lateral impacts with minimal potential risk of failure or adverse collateral impacts. (2) The slow release of TCE from clay and sandstone into the Gallia represent a long term source of TCE that can re-contaminate the Gallia in the future - technologies that effectively treat the permeable portions of the Gallia, but do not leave residual treatment capacity in the system are unlikely to achieve long term remedial action objectives. CDM, the site contractor, provided important and useful information documenting the status and preliminary results of the on-site technology alternative evaluation. In the CDM evaluation, potential technologies were either retained (or screened out) in two preliminary evaluation phases and a detailed evaluation was performed on the five alternatives that were retained into the final 'detailed analysis' phase. The five alternatives that were included in the detailed analysis were: (1) hydraulic fracturing with EHC (a solid bioremediation amendment), (2) enhanced anaerobic bioremediation, (3) in situ chemical oxidation, (4) electrical resistance heating, and (5) reactive barriers. In several cases, two or three variants were separately evaluated. The review team found the CDM effort to be generally credible and reasonable. Thus, the review team focused on providing additional considerations and inputs to Portsmouth and on amending and refining the alternatives in ways that might improve performance and/or reduce costs. The Department of Energy Portsmouth Paducah Project Office requested assistance from Department of Energy Office of

Radiation danger of exclusion zone objects

International Nuclear Information System (INIS)

Kholosha, V.I.; Proskura, N.I.; Ivanov, Yu.A.; Kazakov, S.V.; Arkhipov, A.N.

2001-01-01

The analysis of radiation danger of the Exclusion Zone objects was made. Here, the Zone is defined as the territory from which the population has been evacuated in 1986 owing to the Chernobyl accident and possible outflow of the contaminated substances out of the borders is potentially dangerous to the Ukraine. In the present work were analyzed such problems as sources of radiation danger in the Zone, ways of radionuclide migration out of the borders of the Zone in normal and emergency situations, the non-radiation (ecological) danger factors of the Zone objects, doses (individual and collective) from various sources and on separate ways of their formation, and the characteristics of radiation danger of the Zone objects. The conclusions are: (1) Radionuclide flows both from technologic and natural sources exceed those from Shelter objects, (2) Under emergency conditions, radionuclide flows and doze loading remain comparable with those from emergency sources, (3) To solve some management tasks in radiation situation, the basic works on the Shelter objects should be oriented to decrease probability of emergency occurrence and to reduce radiation influence (prevention wash-outs during high waters, fire-prevention measures in forests and strengthening of the control behind non-authorized use of objects in the Zone). (S. Ohno)

Sorption of colloids, organics, and metals onto gas-water interfaces: Transport mechanisms and potential remediation technology. 1998 annual progress report

International Nuclear Information System (INIS)

Tokunaga, T.K.; Wan, J.

1998-01-01

'Although contaminant sorption at mineral surfaces has received much recognition as a major mechanism controlling contaminant behavior in subsurface environments, virtually no attention has been given to the possibility of contaminant sorption at gas-water interfaces. Moreover, no effort has yet been advanced to optimize such interactions for the purpose of facilitating in-situ remediation. Gas-water interfaces, unlike water-solid interfaces, are mobile. Therefore, associations of contaminants with gas-water interfaces can be very important not only in subsurface contaminant distributions, but also in contaminant transport, and potentially in remediation. The first objective of this research is to develop a quantitative understanding of interactions between contaminants and gas-water interfaces. The anticipated results will provide insights into the poorly understood phenomenon of contaminant interactions with the gas-water interface, and improve the current conceptual models of contaminant behavior in subsurface environments. The second purpose of this research is to explore the possibility of using surfactant stabilized microbubbles for in-situ remediation. Both pump-and-treat, and air sparging remediation methods are ineffective at displacing contaminants in zones which are advectively inaccessible. Stable microbubbles can migrate beyond preferential flow pathways and enter lower permeability zones by buoyant rise. The microbubbles can deliver oxygen and nutrients for promoting aerobic degradation of organic contaminants, and also deliver surfactants for emulsifying NAPLs.'

[Transfer characteristic and source identification of soil heavy metals from water-level-fluctuating zone along Xiangxi River, three-Gorges Reservoir area].

Science.gov (United States)

Xu, Tao; Wang, Fei; Guo, Qiang; Nie, Xiao-Qian; Huang, Ying-Ping; Chen, Jun

2014-04-01

Transfer characteristics of heavy metals and their evaluation of potential risk were studied based on determining concentration of heavy metal in soils from water-level-fluctuating zone (altitude:145-175 m) and bank (altitude: 175-185 m) along Xiangxi River, Three Gorges Reservoir area. Factor analysis-multiple linear regression (FA-MLR) was employed for heavy metal source identification and source apportionment. Results demonstrate that, during exposing season, the concentration of soil heavy metals in water-level-fluctuation zone and bank showed the variation, and the concentration of soil heavy metals reduced in shallow soil, but increased in deep soil at water-level-fluctuation zone. However, the concentration of soil heavy metals reduced in both shallow and deep soil at bank during the same period. According to the geoaccumulation index,the pollution extent of heavy metals followed the order: Cd > Pb > Cu > Cr, Cd is the primary pollutant. FA and FA-MLR reveal that in soils from water-level-fluctuation zone, 75.60% of Pb originates from traffic, 62.03% of Cd is from agriculture, 64.71% of Cu and 75.36% of Cr are from natural rock. In soils from bank, 82.26% of Pb originates from traffic, 68.63% of Cd is from agriculture, 65.72% of Cu and 69.33% of Cr are from natural rock. In conclusion, FA-MLR can successfully identify source of heavy metal and compute source apportionment of heavy metals, meanwhile the transfer characteristic is revealed. All these information can be a reference for heavy metal pollution control.

Arsenic in the groundwater: Occurrence, toxicological activities, and remedies.

Science.gov (United States)

Jha, S K; Mishra, V K; Damodaran, T; Sharma, D K; Kumar, Parveen

2017-04-03

Arsenic (As) contamination in groundwater has become a geo-environmental as well as a toxicological problem across the globe affecting more than 100-million people in nearly 21 countries with its associated disease "arsenicosis." Arsenic poisoning may lead to fatal skin and internal cancers. In present review, an attempt has been made to generate awareness among the readers about various sources of occurrence of arsenic, its geochemistry and speciation, mobilization, metabolism, genotoxicity, and toxicological exposure on humans. The article also emphasizes the possible remedies for combating the problem. The knowledge of these facts may help to work on some workable remedial measure.

Radiation protection zoning

International Nuclear Information System (INIS)

2015-01-01

Radiation being not visible, the zoning of an area containing radioactive sources is important in terms of safety. Concerning radiation protection, 2 work zones are defined by regulations: the monitored zone and the controlled zone. The ministerial order of 15 may 2006 settles the frontier between the 2 zones in terms of radiation dose rates, the rules for access and the safety standards in both zones. Radioprotection rules and the name of the person responsible for radiation protection must be displayed. The frontier between the 2 zones must be materialized and marked with adequate equipment (specific danger signs and tapes). Both zones are submitted to selective entrance, the access for the controlled zone is limited because of the radiation risk and of the necessity of confining radioactive contamination while the limitation of the access to the monitored zone is due to radiation risk only. (A.C.)

Evaluation of select trade-offs between ground-water remediation and waste minimization for petroleum refining industry

International Nuclear Information System (INIS)

Andrews, C.D.; McTernan, W.F.; Willett, K.K.

1996-01-01

An investigation comparing environmental remediation alternatives and attendant costs for a hypothetical refinery site located in the Arkansas River alluvium was completed. Transport from the land's surface to and through the ground water of three spill sizes was simulated, representing a base case and two possible levels of waste minimization. Remediation costs were calculated for five alternative remediation options, for three possible regulatory levels and alternative site locations, for four levels of technology improvement, and for eight different years. It is appropriate from environmental and economic perspectives to initiate significant efforts and expenditures that are necessary to minimize the amount and type of waste produced and disposed during refinery operations; or conversely, given expected improvements in technology, is it better to wait until remediation technologies improve, allowing greater environmental compliance at lower costs? The present work used deterministic models to track a light nonaqueous phase liquid (LNAPL) spill through the unsaturated zone to the top of the water table. Benzene leaching from LNAPL to the ground water was further routed through the alluvial aquifer. Contaminant plumes were simulated over 50 yr of transport and remediation costs assigned for each of the five treatment options for each of these years. The results of these efforts show that active remediation is most cost effective after a set point or geochemical quasi-equilibrium is reached, where long-term improvements in technology greatly tilt the recommended option toward remediation. Finally, the impacts associated with increasingly rigorous regulatory levels present potentially significant penalties for the remediation option, but their likelihood of occurrence is difficult to define

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...

2011 Remediation Effectiveness Report for the U.S. Department of Energy Oak Ridge Reservation, Oak Ridge, Tennessee - Data and Evaluations

Energy Technology Data Exchange (ETDEWEB)

Bechtel Jacobs

2011-03-01

watershed scale, such as contaminant trends at surface water integration points (IFs). Long-term stewardship (LTS) information used in this report is collected, compiled, and tracked by the WRRP in conjunction with the Bechtel Jacobs Company LLC (BJC) Surveillance and Maintenance (S&M) program, the BJC Radiation Protection Organization at East Tennessee Technology Park (ETTP), ETTP Environmental Compliance Program, B&W Y-12 Liquid Waste Treatment Operations, and UT Battelle Facilities Management Division. Additionally, documentation verifying the implementation of administrative land use controls (LUCs) [i.e., property record restrictions, property record notices, zoning notices, and excavation/penetration permit (EPP) program] is also obtained from many sources throughout the fiscal year (FY), including County Register of Deeds offices for property record restrictions and property record notices, City Planning Commission for zoning notices, and BJC project engineers for EPP program verification. Copies of this documentation are obtained by the WRRP and maintained with the project RER files.

2010 Remediation Effectiveness Report for the U.S. Department of Energy Oak Ridge Reservation, Oak Ridge, Tennessee - Data and Evaluations

Energy Technology Data Exchange (ETDEWEB)

Bechtel Jacobs

2010-09-01

watershed scale, such as contaminant trends at surface water integration points (IPs). Long-term stewardship (LTS) information used in this report is collected, compiled, and tracked by the WRRP in conjunction with the Bechtel Jacobs Company LLC (BJC) Surveillance and Maintenance (S&M) program, the BJC Radiation Protection Organization at East Tennessee Technology Park (ETTP), and the ETTP Environmental Compliance Program. Additionally, documentation verifying the implementation of administrative land use controls (LUCs) [i.e., property record restrictions, property record notices, zoning notices, and excavation/penetration permit (EPP) program] is also obtained from many sources throughout the fiscal year (FY), including County Register of Deeds offices for property record restrictions and property record notices, City Planning Commission for zoning notices, and BJC project engineers for EPP program verification. Copies of this documentation are obtained by the WRRP and maintained with the project RER files.

Air sparging for subsurface remediation: Numerical analysis using T2VOC

Energy Technology Data Exchange (ETDEWEB)

McCray, J.E.; Falta, R.W. [Clemson Univ. SC (United States)

1995-03-01

Air sparging is under active investigation as a promising remediation technology for aquifers contaminated with folatile organic dense nonaqueous phase liquids (DNAPLs). A theoretical study for the removal of DNAPLs from the subsurface using this technology is presented. T2VOC is used to conduct multiphase numerical simulations of DNAPL removal utilizing a model aquifer with a radially-symmetric geometry. Both homogeneous and macroscale heterogeneous systems are considered. These simulations suggest that DNAPLs are efficiently removed in a zone of contaminant cleanup at relatively low gas saturations within the injected air plume. The zone of effective removal may be referred to as the radius of influence (ROI). The sparging-induced pressure increase below the water table, which may be measured in the field, is recommended as the best method for determining the ROI. Multiphase numerical simulations are used to support this recommendation, to relate the injected gas ROI to the zone of NAPL cleanup, and to illustrate the transient and steady-state aquifer behavior.

Remedial action and waste disposal project: 100-B/C remedial action readiness report

International Nuclear Information System (INIS)

April, J.G.; Bryant, D.L.; Cislo, G.B.

1996-07-01

This Readiness Evaluation Report presents the results of the project readiness evaluation to assess the readiness of the 100-B/C source sites remediation. The 100-B/C Area is located at the Hanford Site in Richland, Washington. The evaluation was conducted at the conclusion of a series of readiness activities that began in May 1996. These activities included confirming the completion of project specific procedures, training of staff, obtaining support equipment, receipt of subcontractor submittals, approval of subcontractor submittals, and mobilization and construction of site support systems

Information needs for demonstrating compliance with groundwater aspects of 40 CFR 192 for uranium mill tailings remedial action programs

International Nuclear Information System (INIS)

Logsdon, M.J.; Verma, T.R.; Martin, D.E.

1984-01-01

Public Law 95-604, the Uranium Mill Tailings Radiation Control Act of 1978, provides the Department of Energy with authority to perform remedial actions at designated inactive uranium-mill sites. The Environmental Protection Agency promulgated radiological and non-radiological standards (40 CFR 192) for remedial actions at inactive uranium-mill sites. All remedial actions require the concurrence of the Nuclear Regulatory Commission. Subpart C of 40 CFR 192 addresses the control of pollutants in groundwater at sites for which remedial action is proposed pursuant to P.L 95-604. As the authors interpret the regulation, it is essentially an admonition to carefully evaluate what is useful and practicable to deal with existing contamination and to control potential future contamination. In reviewing groundwater aspects of Uranium Mill Tailings Remedial Action documents, current NRC experience shows that the reports should address the following information needs: (1) The need to identify the physical and chemical nature of the present groundwater flow system in sufficient detail to provide a reasonable expectation that the extent and value of the groundwater resource to be protected is understood adequately; (2) The need to identify reasonable foreseeable events, both natural and man-made, that could alter the present groundwater flow system and the effects of such changes on the definition of the protected zone; (3) The need to identify current groundwater use within the protected zone; (4) The need to identify site-specific models, boundary conditions, and representative values of system parameters to predict with reasonable assurance that the proposed actions will protect groundwater and surface water resources for the design period of 200 - 1000 years

Cost-effectiveness analysis of radon remediation in schools

International Nuclear Information System (INIS)

Kennedy, C.A.; Gray, A.M.

2000-01-01

Indoor radon is an important source of radiation dosage in the general population and has been recognised as a world-wide environmental and public health challenge. Governments in many Western and Eastern European and North American countries are undertaking active radon-risk reduction policies, including the remediation of existing residential and work place building stocks (1). These endeavours include a priority of remediating school buildings. Epidemiological and technical radon research has produced information which has enabled attention to be turned to specific effectiveness and optimisation questions regarding radon identification and remediation programmes in buildings, including schools. Decision making about policy implementation has been an integral part of these programmes and questions have been raised about the economic implications of the regulations and optimisation strategies for workplace action level policy (2,3). (the action level applied to schools is 400 Bq m -3 ). No previous study has estimated the cost-effectiveness of a radon remediation programme for schools using the methodological framework now considered appropriate in the economic evaluation of health interventions. It is imperative that this should be done, in order that the resources required to obtain health gain from radon remediation in schools can be systematically compared with equivalent data for other health interventions and radon remediation programmes. In this study a cost-effectiveness analysis of radon remediation in schools was undertaken, using the best available national data and information from Northamptonshire on the costs and effectiveness of radon identification and remediation in schools, and the costs and health impact of lung cancer cases. A model based on data from Northamptonshire is presented (where 6.3% of residential stock is over 200 Bq m -3 ). The resultant cost-effectiveness ratio was pound 7,550 per life year gained in pound 1997. Results from the

Independent Technical Review of the C-400 Interim Remedial Project Phase I Results, Paducah, Kentucky

International Nuclear Information System (INIS)

Looney, B.; Rossabi, J.; Stewart, L.; Richards, W.

2010-01-01

The groundwater and soil in the vicinity of the C-400 Building at the Paducah Gaseous Diffusion Plant (PGDP), is contaminated with substantial quantities of industrial solvents, primarily trichoroethene (TCE). This solvent 'source' is recognized as a significant challenge and an important remediation target in the overall environmental cleanup strategy for PGDP. Thus, the cleanup of the C-400 TCE Source is a principal focus for the Department of Energy (DOE) and its contractors, and for PGDP regulators and stakeholders. Using a formal investigation, feasibility study and decision process, Electrical Resistance Heating (ERH) was selected for the treatment of the soil and groundwater in the vicinity of C-400. ERH was selected as an interim action to remove 'a significant portion of the contaminant mass of TCE at the C-400 Cleaning Building area through treatment' with the longer term goal of reducing 'the period the TCE concentration in groundwater remains above its Maximum Contaminant Level (MCL).' ERH is a thermal treatment that enhances the removal of TCE and related solvents from soil and groundwater. The heterogeneous conditions at PGDP, particularly the high permeability regional gravel aquifer (RGA), are challenging to ERH. Thus, a phased approach is being followed to implement this relatively expensive and complex remediation technology. Conceptually, the phased approach encourages safety and efficiency by providing a 'lessons learned' process and allowing appropriate adjustments to be identified and implemented prior to follow-on phase(s) of treatment. More specifically, early deployment targeted portions of the challenging RGA treatment zone with relatively little contamination reducing the risk of adverse collateral impacts from underperformance in terms of heating and capture. Because of the importance and scope of the C-400 TCE source remediation activities, DOE chartered an Independent Technical Review (ITR) in 2007 to assess the C-400 ERH plans prior

INDEPENDENT TECHNICAL REVIEW OF THE C-400 INTERIM REMEDIAL PROJECT PHASE I RESULTS, PADUCAH, KENTUCKY

Energy Technology Data Exchange (ETDEWEB)

Looney, B.; Rossabi, J.; Stewart,L.; Richards, W.

2010-10-29

The groundwater and soil in the vicinity of the C-400 Building at the Paducah Gaseous Diffusion Plant (PGDP), is contaminated with substantial quantities of industrial solvents, primarily trichoroethene (TCE). This solvent 'source' is recognized as a significant challenge and an important remediation target in the overall environmental cleanup strategy for PGDP. Thus, the cleanup of the C-400 TCE Source is a principal focus for the Department of Energy (DOE) and its contractors, and for PGDP regulators and stakeholders. Using a formal investigation, feasibility study and decision process, Electrical Resistance Heating (ERH) was selected for the treatment of the soil and groundwater in the vicinity of C-400. ERH was selected as an interim action to remove 'a significant portion of the contaminant mass of TCE at the C-400 Cleaning Building area through treatment' with the longer term goal of reducing 'the period the TCE concentration in groundwater remains above its Maximum Contaminant Level (MCL).' ERH is a thermal treatment that enhances the removal of TCE and related solvents from soil and groundwater. The heterogeneous conditions at PGDP, particularly the high permeability regional gravel aquifer (RGA), are challenging to ERH. Thus, a phased approach is being followed to implement this relatively expensive and complex remediation technology. Conceptually, the phased approach encourages safety and efficiency by providing a 'lessons learned' process and allowing appropriate adjustments to be identified and implemented prior to follow-on phase(s) of treatment. More specifically, early deployment targeted portions of the challenging RGA treatment zone with relatively little contamination reducing the risk of adverse collateral impacts from underperformance in terms of heating and capture. Because of the importance and scope of the C-400 TCE source remediation activities, DOE chartered an Independent Technical Review (ITR) in

Hypoxia and Nutrient Reduction in the Coastal Zone: Advice for Prevention, Remediation and Research.

Digital Repository Service at National Institute of Oceanography (India)

Meryl Williams, M.; Harper, N.; Chaitovitz, C.; Dansie, A.; Diaz, R.; Harper, N.; Heidemeier, J.; Jiang, Y.; Kemp, M.; Naqvi, S.W.A.; Neretin, L.; Ross, A.; Susan, C.; Schuster-Wallace, C.; Zavadksy, I.

the issue, beyond current actions. This STAP Advisory Document is based on a review of the scien- tific evidence, and scientific and management expert consultations. It has been reviewed by subject matter experts, the GEF Secretariat, the GEF International... limited impact. Intervention areas should be selected based on their expected potential for preven- tion or remediation and progress should be monitored. GEF should establish principles for supporting priority systems in which to test management responses...

Radioactive waste management in the Chernobyl exclusion zone: 25 years since the Chernobyl nuclear power plant accident.

Science.gov (United States)

Oskolkov, Boris Y; Bondarkov, Mikhail D; Zinkevich, Lubov I; Proskura, Nikolai I; Farfán, Eduardo B; Jannik, G Timothy

2011-10-01

Radioactive waste management is an important component of the Chernobyl Nuclear Power Plant accident mitigation and remediation activities in the so-called Chernobyl Exclusion Zone. This article describes the localization and characteristics of the radioactive waste present in the Chernobyl Exclusion Zone and summarizes the pathways and strategy for handling the radioactive waste-related problems in Ukraine and the Chernobyl Exclusion Zone and, in particular, the pathways and strategies stipulated by the National Radioactive Waste Management Program.

Fiscal Year 2008 Phased Construction Completion Report for EU Z2-33 in Zone 2, East Tennessee Technology Park, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

Bechtel Jacobs

2008-09-11

The Record of Decision for Soil, Buried Waste, and Subsurface Structure Actions in Zone 2, East Tennessee Technology Park, Oak Ridge, Tennessee (DOE/OR/01-2161&D2) (Zone 2 ROD) acknowledged that most of the 800 acres in Zone 2 were contaminated, but that sufficient data to confirm the levels of contamination were lacking. The Zone 2 ROD further specified that a sampling strategy for filling the data gaps would be developed. The Remedial Design Report/Remedial Action Work Plan for Zone 2 Soils, Slabs, and Subsurface Structures, East Tennessee Technology Park, Oak Ridge, Tennessee (DOE/OR/01-2224&D3) (Zone 2 RDR/RAWP) defined the sampling strategy as the Dynamic Verification Strategy (DVS), generally following the approach used for characterization of the Zone 1 exposure units (EUs). The Zone 2 ROD divided the Zone 2 area into seven geographic areas and 44 EUs. To facilitate the data quality objectives (DQOs) of the DVS process, the Zone 2 RDR/RAWP regrouped the 44 EUs into 12 DQO scoping EU groups. These groups facilitated the DQO process by placing similar facilities and their support facilities together and allowing identification of data gaps. The EU groups were no longer pertinent after DQO planning was completed and characterization was conducted as areas became accessible. As the opportunity to complete characterization became available, the planned DVS program and remedial actions (RAs) were completed for EU Z2-33. Remedial action was also performed at two additional areas in adjacent EU Z2-42 because of their close proximity and similar nature to a small surface soil RA in EU Z2-33. Remedial actions for building slabs performed in EU Z2-33 during fiscal year (FY) 2007 were reported in the Fiscal Year 2007 Phased Construction Completion Report for the Zone 2 Soils, Slabs, and Subsurface Structures at East Tennessee Technology Park, Oak Ridge, Tennessee (DOE/OR/01-2723&D1). Recommended RAs for EU Z2-42 were described in the Fiscal Year 2006 Phased Construction

Cultures of Science and Technology in the Trading Zone: Biodiversity and Open Source Development

OpenAIRE

Heaton , Lorna; Dias da Silva , Patrícia

2016-01-01

International audience; This paper explores the work of building open source biodiversity information infrastructure. We analyse collaboration between a Canadian team and a Brazilian one. In particular we focus on the use of WingLongitude, a GitHub space, as a trading zone within which the two teams co-developed solutions. We show how the choice to work in a neutral space, belonging to everyone, and the use of display, representation and assemblage practices enabled sharing of some infrastruc...

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

Enhanced phytoremediation in the vadose zone: Modeling and column studies

Science.gov (United States)

Sung, K.; Chang, Y.; Corapcioglu, M.; Cho, C.

2002-05-01

Phytoremediation is a plant-based technique with potential for enhancing the remediation of vadoese zone soils contaminated by pollutants. The use of deep-rooted plants is an alternative to conventional methodologies. However, when the phytoremediation is applied to the vadose zone, it might have some restrictions since it uses solely naturally driven energy and mechanisms in addition to the complesxity of the vadose zone. As a more innovative technique than conventional phytoremediation methods, air injected phytoremediation technique is introduced to enhance the remediation efficiency or to apply at the former soil vapor extraction or bio venting sites. Effects of air injection, vegetation treatment, and air injection with vegetation treatments on the removal of hydrocarbon were investigated by column studies to simulate the field situation. Both the removal efficiency and the microbial activity were highest in air-injected and vegetated column soils. It was suggested that increased microorganisms activity stimulated by plant root exudates enhanced biodegradation of hydrocarbon compounds. Air injection provided sufficient opportunity for promoting the microbial activity at depths where the conditions are anaerobic. Air injection can enhance the physicochemical properties of the medium and contaminant and increase the bioavailability i.e., the plant and microbial accessibility to the contaminant. A mathematical model that can be applied to phytoremediation, especially to air injected phytoremediation, for simulating the fate and the transport of a diesel contaminant in the vadose zone is developed. The approach includes a two-phase model of water flow in vegetated and unplanted vadose zone soil. A time-specific root distribution model and a microbial growth model in the rhizosphere of vegetated soil were combined with an unsaturated soil water flow equation as well as with a contaminant transport equation. The proposed model showed a satisfactory representation of

Remediation of Manufactured Methamphetamine in Clandestine Laboratories. A Literature Review

Science.gov (United States)

The purpose of the current literature review was to identify, collect, review, and organize all available information concerning the remediation of methamphetamine found in clandestine laboratories through an analysis of routinely collected data sources. There were numerous peer ...

Theoretical basis of remediation of heavy metal contamination by apatite

International Nuclear Information System (INIS)

Raicevic, S.; Mandic, M.; Kaludjerovic, T.

2001-01-01

Recently we have demonstrated the connection between stability of the products of the in situ remediation processes and their values of the ion-ion interaction potential, representing the main term of the cohesive energy. Using this approach, the stability of the products of remediation of Pb and Cd by hydroxyapatite (HAP) was investigated. It has been demonstrated that incorporation of Pb ions from pyromorphite into HAP is followed by a decrease of the cohesive energy, indicating that in remediation of Pb, HAP serves as a source of components necessary for formation of a stabile Pb-apatite phase which is precipitated on the surface of the HAP particles. Contrary, incorporation of Cd from the Cd-apatite into HAP increases the cohesive energy of the system, suggesting that the precipitated Cd-apatite phase is later transformed into a more stabile HAP/Cd solid solution. The presented results of theoretical analysis are in good accordance with the reported experimental results. Based on the results of this analysis, the general criterion for estimation of stability of the products of the in situ remediation processes was proposed. (author)

Remediation of soils combining soil vapor extraction and bioremediation: benzene.

Science.gov (United States)

Soares, António Alves; Albergaria, José Tomás; Domingues, Valentina Fernandes; Alvim-Ferraz, Maria da Conceição M; Delerue-Matos, Cristina

2010-08-01

This work reports the study of the combination of soil vapor extraction (SVE) with bioremediation (BR) to remediate soils contaminated with benzene. Soils contaminated with benzene with different water and natural organic matter contents were studied. The main goals were: (i) evaluate the performance of SVE regarding the remediation time and the process efficiency; (ii) study the combination of both technologies in order to identify the best option capable to achieve the legal clean up goals; and (iii) evaluate the influence of soil water content (SWC) and natural organic matter (NOM) on SVE and BR. The remediation experiments performed in soils contaminated with benzene allowed concluding that: (i) SVE presented (a) efficiencies above 92% for sandy soils and above 78% for humic soils; (b) and remediation times from 2 to 45 h, depending on the soil; (ii) BR showed to be an efficient technology to complement SVE; (iii) (a) SWC showed minimum impact on SVE when high airflow rates were used and led to higher remediation times for lower flow rates; (b) NOM as source of microorganisms and nutrients enhanced BR but hindered the SVE due the limitation on the mass transfer of benzene from the soil to the gas phase. (c) 2010 Elsevier Ltd. All rights reserved.

Independent Verification Survey Report For Zone 1 Of The East Tennessee Technology Park In Oak Ridge, Tennessee

International Nuclear Information System (INIS)

King, David A.

2012-01-01

Oak Ridge Associated Universities (ORAU) conducted in-process inspections and independent verification (IV) surveys in support of DOE's remedial efforts in Zone 1 of East Tennessee Technology Park (ETTP) in Oak Ridge, Tennessee. Inspections concluded that the remediation contractor's soil removal and survey objectives were satisfied and the dynamic verification strategy (DVS) was implemented as designed. Independent verification (IV) activities included gamma walkover surveys and soil sample collection/analysis over multiple exposure units (EUs)

Earthquake source parameters along the Hellenic subduction zone and numerical simulations of historical tsunamis in the Eastern Mediterranean

Science.gov (United States)

Yolsal-Çevikbilen, Seda; Taymaz, Tuncay

2012-04-01

We studied source mechanism parameters and slip distributions of earthquakes with Mw ≥ 5.0 occurred during 2000-2008 along the Hellenic subduction zone by using teleseismic P- and SH-waveform inversion methods. In addition, the major and well-known earthquake-induced Eastern Mediterranean tsunamis (e.g., 365, 1222, 1303, 1481, 1494, 1822 and 1948) were numerically simulated and several hypothetical tsunami scenarios were proposed to demonstrate the characteristics of tsunami waves, propagations and effects of coastal topography. The analogy of current plate boundaries, earthquake source mechanisms, various earthquake moment tensor catalogues and several empirical self-similarity equations, valid for global or local scales, were used to assume conceivable source parameters which constitute the initial and boundary conditions in simulations. Teleseismic inversion results showed that earthquakes along the Hellenic subduction zone can be classified into three major categories: [1] focal mechanisms of the earthquakes exhibiting E-W extension within the overriding Aegean plate; [2] earthquakes related to the African-Aegean convergence; and [3] focal mechanisms of earthquakes lying within the subducting African plate. Normal faulting mechanisms with left-lateral strike slip components were observed at the eastern part of the Hellenic subduction zone, and we suggest that they were probably concerned with the overriding Aegean plate. However, earthquakes involved in the convergence between the Aegean and the Eastern Mediterranean lithospheres indicated thrust faulting mechanisms with strike slip components, and they had shallow focal depths (h < 45 km). Deeper earthquakes mainly occurred in the subducting African plate, and they presented dominantly strike slip faulting mechanisms. Slip distributions on fault planes showed both complex and simple rupture propagations with respect to the variation of source mechanism and faulting geometry. We calculated low stress drop

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.

Direct measurement and characterization of active photosynthesis zones inside biofuel producing and wastewater remediating microalgal biofilms

Energy Technology Data Exchange (ETDEWEB)

Bernstein, Hans C.; Kesaano, Maureen; Moll, Karen; Smith, Terence; Gerlach, Robin; Carlson, Ross; Miller, Charles D.; Peyton, Brent; Cooksey, Keith; Gardner, Robert D.; Sims, Ronald C.

2014-03-01

Abstract: Microalgal biofilm based technologies are of keen interest due to their high biomass concentrations and ability to utilize renewable resources, such as light and CO2. While photoautotrophic biofilms have long been used for wastewater remediation applications, biofuel production represents a relatively new and under-represented focus area. However, the direct measurement and characterization of fundamental parameters required for physiological analyses are challenging due to biofilm heterogeneity. This study evaluated oxygenic photosynthesis and biofuel precursor molecule production using a novel rotating algal biofilm reactor (RABR) operated at field- and laboratory-scales for wastewater remediation and biofuel production, respectively. Clear differences in oxygenic-photosynthesis, respiration and biofuel-precursor capacities were observed between the two systems and different conditions based on light and nitrogen availability. Nitrogen depletion was not found to have the same effect on lipid accumulation compared to prior planktonic studies. Physiological characterizations of these microalgal biofilms identify potential areas for future process optimization.

Feasibility study of a self-remediation system for mine drainage using its thermal energy

Science.gov (United States)

Oh, Chamteut; Cheong, Youngwook; Yim, Giljae; Ji, Sangwoo

2016-04-01

Mine drainage is defined as the water which is discharged to the ground surface through shafts and/or cracks formed by mining activities. Typically, mine drainage features high concentration of acidity and metals since it passes through the underground. Therefore, for the purpose of protecting the surrounding natural environment, mine drainage should be remediated before being discharged to nature. Mine drainage, due to its nature of being retained underground, shows constant temperature which is independent from the temperature of the atmosphere above ground. This condition allows mine drainage to become a promising renewable energy source since energy can be recovered from water with constant temperature. In this research, a self-remediation system is proposed which remediates the mine drainage through electrochemical reactions powered by the thermal energy of mine drainage. High energy efficiency is able to be achieved by shortening the distance between the energy source and consumption, and therefore, this system has a strong advantage to be actualized. A feasibility study for the system was conducted in this research where the thermal energy of mine drainage over time and depth was calculated as energy supply and the required electrical energy for remediating the mine drainage was measured as energy consumption. While the technology of converting thermal energy directly into electrical energy is yet to be developed, energy balance analysis results showed that the proposed self-remediation system is theoretically possible.

Integrated geophysical investigations for the delineation of source and subsurface structure associated with hydro-uranium anomaly: A case study from South Purulia Shear Zone (SPSZ), India

Science.gov (United States)

Sharma, S. P.; Biswas, A.

2012-12-01

South Purulia Shear Zone (SPSZ) is an important region for prospecting of uranium mineralization. Geological studies and hydro-uranium anomaly suggest the presence of Uranium deposit around Raghunathpur village which lies about 8 km north of SPSZ. However, detailed geophysical investigations have not been carried out in this region for investigation of uranium mineralization. Since surface signature of uranium mineralization is not depicted near the location, a deeper subsurface source is expected for hydro uranium anomaly. To delineate the subsurface structure and to investigate the origin of hydro-uranium anomaly present in the area, Vertical Electrical Sounding (VES) using Schlumberger array and Gradient Resistivity Profiling (GRP) were performed at different locations along a profile perpendicular to the South Purulia Shear Zone. Apparent resistivity computed from the measured sounding data at various locations shows a continuously increasing trend. As a result, conventional apparent resistivity data is not able to detect the possible source of hydro uranium anomaly. An innovative approach is applied which depicts the apparent conductivity in the subsurface revealed a possible connection from SPSZ to Raghunathpur. On the other hand resistivity profiling data suggests a low resistive zone which is also characterized by low Self-Potential (SP) anomaly zone. Since SPSZ is characterized by the source of uranium mineralization; hydro-uranium anomaly at Raghunathpur is connected with the SPSZ. The conducting zone has been delineated from SPSZ to Raghunathpur at deeper depths which could be uranium bearing. Since the location is also characterized by a low gravity and high magnetic anomaly zone, this conducting zone is likely to be mineralized zone. Keywords: Apparent resistivity; apparent conductivity; Self Potential; Uranium mineralization; shear zone; hydro-uranium anomaly.

Remedial actions at the former Union Carbide Corporation uranium mill sites, Rifle, Garfield County, Colorado

International Nuclear Information System (INIS)

1990-03-01

This appendix provides the information needed to understand the conceptual designs for the remedial action alternatives addressed in this environmental impact statement (EIS). It is intended to provide sufficient details for the reader to evaluate the feasibility and assess the impacts of each remedial action alternative. It is not intended to provide the detailed engineering necessary to implement the alternatives. Details of the preferred remedial action will be presented in the remedial action plan (RAP). The remedial action alternatives addressed in this EIS include no action, stabilization at the New Rifle site, disposal at the Estes Gulch site, and disposal at the Lucas Mesa site. All alternatives include interim actions to remediate existing health and safety hazards to the Rifle community that presently exist at the Old and New Rifle processing sites. It should be noted that the borrow sites included in this EIS were selected as the sources of the necessary borrow materials for impacts analyses purposes only. The borrow sites to be used for the remedial action will be selected during the final design. 21 figs., 18 tabs

A numerical solution to three-dimensional multiphase transport of volatile organic compounds in unsaturated soils -- with an application to the remedial method of in-situ volatilization

International Nuclear Information System (INIS)

Filley, T.; Tomasko, D.

1992-04-01

Part I of this paper presents the development and application of a numerical model for determining the fate and transport of volatile organic compounds (VOCS) in the unsaturated zone resulting from forced volatilization and gaseous advection-dispersion of organic vapor in a multipartitioned three-dimensional environment. The model allows for single-component transport in the gas and water phases. The hydrocarbon is assumed to be in specific retention and, therefore, immobile. Partitioning of the hydrocarbon between the oil, water, gas, and soil is developed as rate-limited functions that are incorporated into sink/source terms in the transport equations. The code for the model was developed specifically to investigate in-situ volatilization (ISV) remedial strategies, predict the extent of cleanup from information obtained at a limited number of measurement locations, and to help design ISV remedial systems. Application of the model is demonstrated for a hypothetical one-dimensional ISV system. Part II of this paper will present the analysis of an existing ISV system using the full three-dimensional capability of the model

Using geophysical techniques to control in situ thermal remediation

International Nuclear Information System (INIS)

Boyd, S.; Daily, W.; Ramirez, A.; Wilt, M.; Goldman, R.; Kayes, D.; Kenneally, K.; Udell, K.; Hunter, R.

1994-01-01

Monitoring the thermal and hydrologic processes that occur during thermal environmental remediation programs in near real-time provides essential information for controlling the process. Geophysical techniques played a crucial role in process control as well as for characterization during the recent Dynamic Underground Stripping Project demonstration in which several thousand gallons of gasoline were removed from heterogeneous soils both above and below the water table. Dynamic Underground Stripping combines steam injection and electrical heating for thermal enhancement with ground water pumping and vacuum extraction for contaminant removal. These processes produce rapid changes in the subsurface properties including changes in temperature fluid saturation, pressure and chemistry. Subsurface imaging methods are used to map the heated zones and control the thermal process. Temperature measurements made in wells throughout the field reveal details of the complex heating phenomena. Electrical resistance tomography (ERT) provides near real-time detailed images of the heated zones between boreholes both during electrical heating and steam injection. Borehole induction logs show close correlation with lithostratigraphy and, by identifying the more permeable gravel zones, can be used to predict steam movement. They are also useful in understanding the physical changes in the field and in interpreting the ERT images. Tiltmeters provide additional information regarding the shape of the steamed zones in plan view. They were used to track the growth of the steam front from individual injectors

Evaluation of home lead remediation in an Australian mining community.

Science.gov (United States)

Boreland, F; Lesjak, M; Lyle, D

2009-12-20

In 1994 a comprehensive program was established to reduce children's blood lead levels in Broken Hill, NSW, Australia. Home remediation (abatement of lead hazards in a child's home) was included as part of a case management strategy for children with blood lead levels >or=15 microg/dL. Children with blood lead levels >or=30 microg/dL were offered immediate home remediation. Children with blood lead levels of 15-29 microg/dL were allocated to 'immediate' or 'delayed' home remediation; a subset of these participated in a randomized controlled trial (RCT) to evaluate the effectiveness of home remediation for reducing blood lead levels. One hundred and seventeen children received home remediation. One hundred and thirteen returned for follow-up blood tests, 88 of whom participated in the RCT. On average children's blood lead levels decreased by 1.7 microg/dL (10%) in the 6 months after remediation and by 2.2 microg/dL (13%) in the 6-12 months after remediation. However, remediation did not significantly change the rate of decline in blood lead levels (P=0.609). There was no evidence of association between change in children's blood lead levels and changes in lead loading in their homes. The results are consistent with the published literature, which suggests that home remediation does not reduce children's exposure to lead sufficiently to cause a moderate or greater decrease in their blood lead level. In communities where lead is widely dispersed, the study suggests that it is important to assess potential sources and pathways by which children are exposed to lead when developing an intervention plan, and the need for multiple interventions to effectively reduce blood lead levels. The findings reinforce the ongoing need for rigorous epidemiological evaluation of lead management programs to improve the evidence base, and for effective primary prevention to avoid children being exposed to lead in the first place.

Biochemical basis of mercury remediation and bioaccumulation by Enterobacter sp. EMB21.

Science.gov (United States)

Sinha, Arvind; Kumar, Sumit; Khare, Sunil Kumar

2013-01-01

The aims of this study were to isolate metal bioaccumulating bacterial strains and to study their applications in removal of environmental problematic heavy metals like mercury. Five bacterial strains belonging to genera Enterobacter, Bacillus, and Pseudomonas were isolated from oil-spilled soil. Among these, one of the strains Enterobacter sp. EMB21 showed mercury bioaccumulation inside the cells simultaneous to its bioremediation. The bioaccumulation of remediated mercury was confirmed by transmission electron microscopy and energy dispersive X-ray. The mercury-resistant loci in the Enterobacter sp. EMB21 cells were plasmid-mediated as confirmed by transformation of mercury-sensitive Escherichia coli DH5α by Enterobacter sp. EMB21 plasmid. Effect of different culture parameters viz-a-viz inoculum size, pH, carbon, and nitrogen source revealed that alkaline pH and presence of dextrose and yeast extract favored better remediation. The results indicated the usefulness of Enterobacter sp. EMB21 for the effective remediation of mercury in bioaccumulated form. The Enterobacter sp. EMB21 seems promising for heavy metal remediation wherein the remediated metal can be trapped inside the cells. The process can further be developed for the synthesis of valuable high-end functional alloy, nanoparticles, or metal conjugates from the metal being remediated.

Remedial investigation for the chemical plant area of the Weldon Spring Site

International Nuclear Information System (INIS)

1992-11-01

The US Department of Energy (DOE) is responsible for management of the Weldon Spring Site Remedial Action Project (WSSRAP) under its Environmental Restoration and Waste Management Program. Major goals include eliminating potential public and environmental hazards due to site contamination and releasing the property for alternate uses to the maximum extent practicable. The purpose of the remedial investigation described in this report was to determine the extent of contamination associated with the portion of the Weldon Spring site known as the chemical plant and raffinate pit area. The DOE has assumed responsibility for investigating and remediating all on-site soil contamination and off-site soil which is radiologically contaminated as a result of uranium and thorium processing operations. The DOE has also assumed the responsibility for radiologically contaminated groundwater on and off site. The Weldon Spring site remedial investigation also involved the evaluation of the sources, nature and extent, and environmental fate and transport of contaminants to provide a basis for defining the risks that the contaminants may pose to human health and the environment. Data are included in this report to support the screening of remedial technologies and to permit the development and detailed analysis of alternatives for remedial action at the site during the feasibility study process

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.

Biostimulation of anaerobic BTEX biodegradation under fermentative methanogenic conditions at source-zone groundwater contaminated with a biodiesel blend (B20).

Science.gov (United States)

Ramos, Débora Toledo; da Silva, Márcio Luis Busi; Chiaranda, Helen Simone; Alvarez, Pedro J J; Corseuil, Henry Xavier

2013-06-01

Field experiments were conducted to assess the potential for anaerobic biostimulation to enhance BTEX biodegradation under fermentative methanogenic conditions in groundwater impacted by a biodiesel blend (B20, consisting of 20 % v/v biodiesel and 80 % v/v diesel). B20 (100 L) was released at each of two plots through an area of 1 m(2) that was excavated down to the water table, 1.6 m below ground surface. One release was biostimulated with ammonium acetate, which was added weekly through injection wells near the source zone over 15 months. The other release was not biostimulated and served as a baseline control simulating natural attenuation. Ammonium acetate addition stimulated the development of strongly anaerobic conditions, as indicated by near-saturation methane concentrations. BTEX removal began within 8 months in the biostimulated source zone, but not in the natural attenuation control, where BTEX concentrations were still increasing (due to source dissolution) 2 years after the release. Phylogenetic analysis using quantitative PCR indicated an increase in concentration and relative abundance of Archaea (Crenarchaeota and Euryarchaeota), Geobacteraceae (Geobacter and Pelobacter spp.) and sulfate-reducing bacteria (Desulfovibrio, Desulfomicrobium, Desulfuromusa, and Desulfuromonas) in the biostimulated plot relative to the control. Apparently, biostimulation fortuitously enhanced the growth of putative anaerobic BTEX degraders and associated commensal microorganisms that consume acetate and H2, and enhance the thermodynamic feasibility of BTEX fermentation. This is the first field study to suggest that anaerobic-methanogenic biostimulation could enhance source zone bioremediation of groundwater aquifers impacted by biodiesel blends.

Electrokinetic Enhanced Permanganate Delivery for Low Permeability Soil Remediation

Science.gov (United States)

Chowdhury, A. I.; Gerhard, J.; Reynolds, D. A.; Sleep, B. E.; O'Carroll, D. M.

2016-12-01

Contaminant mass sequestered in low permeability zones (LPZ) in the subsurface has become a significant concern due to back diffusion of contaminants, leading to contaminant rebound following treatment of the high permeability strata. In-situ remediation technologies such as in-situ chemical oxidation (ISCO) are promising, however, successful delivery of oxidants into silts and clays remains a challenge. Electrokinetics (EK) has been proposed as a technique that can overcome this challenge by delivering oxidants into low permeability soils. This study demonstrates the ability of EK to facilitate permanganate delivery into silt for treatment of trichloroethene (TCE). A two-dimensional sandbox was packed with alternate vertical layers of coarse sand and silt contaminated with high concentrations of aqueous phase TCE. Nine experiments were conducted to compare EK-enhanced in-situ chemical oxidation (EK-ISCO) to ISCO alone or EK alone. Frequent groundwater sampling at multiple locations combined with image analysis provided detailed mapping of TCE, permanganate, and manganese dioxide mass distributions. EK-ISCO successfully delivered the permanganate throughout the silt cross-section while ISCO without EK resulted in permanganate delivery only to the edges of the silt layer. EK-ISCO resulted in a 4.4 order-of-magnitude (OoM) reduction in TCE concentrations in the coarse sand compared to a 3.5 OoM reduction for ISCO alone. This study suggests that electrokinetics coupled with ISCO can achieve enhanced remediation of lower permeability strata, where remediation technologies for successful contaminant mass removal would otherwise be limited.

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

Cornell Mixing Zone Expert System

Science.gov (United States)

This page provides an overview Cornell Mixing Zone Expert System water quality modeling and decision support system designed for environmental impact assessment of mixing zones resulting from wastewater discharge from point sources

Large-scale sulfolane-impacted soil remediation at a gas plant

Energy Technology Data Exchange (ETDEWEB)

Lavoie, G.; Rockwell, K. [Biogenie Inc., Calgary, AB (Canada)

2006-07-01

A large-scale sulfolane-impacted soil remediation project at a gas plant in central Alberta was discussed. The plant was operational from the 1960s to present and the former operation involved the Sulfinol process which resulted in groundwater contamination. In 2005, the client wanted to address the sources area. The Sulfinol process has been used since the 1960s to remove hydrogen sulfide and other corrosive gases from natural gas streams. Sulfinol uses sulfolane and diisopropanolamine. Sulfolane is toxic, non-volatile, and water soluble. The presentation also addressed the remediation objectives and an additional site assessment that was conducted to better delineate the sulfolane and sulphur plume, as well as metals. The findings of the ESA and site specific challenges were presented. These challenges included: plant operation concerns; numerous overhead, surface, and underground structures; large volume of impacted material, limited space available on site; several types of contaminants; and time required to perform the overall work. Next, the sulfolane remediation strategy was discussed including advantages and results of the investigation. Last, the results of the project were presented. It was found that there were no recordable safety incidents and that all remedial objectives were achieved. tabs., figs.

Lead remediation and changes in human lead exposure: some physiological and biokinetic dimensions.

Science.gov (United States)

Mushak, Paul

2003-02-15

This paper presents a qualitative and quantitative analysis of the various aspects of lead remediation effectiveness with particular reference to human health risk assessment. One of the key elements of lead remediation efforts at such sites as those under the Superfund program deals with populations at elevated exposure and toxicity risk in the proximity of, or at, the site of remediation, especially remediation workers, workers at other tasks on sites that were remediated down to some action level of lead concentration in soils, and groups at risk in nearby communities. A second element has to do with how one measures or models lead exposure changes with special reference to baseline and post-remediation conditions. Various biomarkers of lead exposure can be employed, but their use requires detailed knowledge of what results using each means. The most commonly used approach is measurement of blood lead (Pb-B). Recognized limitations in the use of Pb-B has led to the use of predictive Pb exposure models, which are less vulnerable to the many behavioral, physiological, and environmental parameters that can distort isolated or 'single shot' Pb-B testings. A third aspect covered in this paper presents various physiological factors that affect the methods by which one evaluates Pb remediation effectiveness. Finally, this article offers an integrated look at how lead remediation actions directed at one lead source or pathway affect the total lead exposure picture for human populations at elevated lead exposure and toxicity risk.

Remediation of attention deficits in head injury.

OpenAIRE

Nag S; Rao S

1999-01-01

Head injury is associated with psychological sequelae which impair the patient′s psychosocial functioning. Information processing, attention and memory deficits are seen in head injuries of all severity. We attempted to improve deficits of focused, sustained and divided attention. The principle of overlapping sources of attention resource pools was utilised in devising the remediation programme. Tasks used simple inexpensive materials. Four head injured young adult males with post conc...

Technical options for the remediation of contaminated groundwater

Energy Technology Data Exchange (ETDEWEB)

1999-06-01

This report provides a description of the nature and extent of problems related to radioactive groundwater contamination by outlining the environmental impacts, the sources of contamination and the contaminants of concern radionuclides and their associated contaminants - the main exposure pathways and transport processes and the assessment of risks associated with contaminated groundwater. The main emphasis of this report is on methodologies used in groundwater remediation and available technologies. The methodology section outlines the importance of an initial scoping analysis including the evaluation of uncertainties of the available data and the necessity for defining clear objectives for data collection. This is then followed by comprehensive site characterization, setting of goals and developing alternatives which will be analysed in detail. Available technologies are grouped generally into in situ methods aiming at a containment of the contaminants in place and engineered treatment methods involving an alteration of groundwater flow, quantity and/or quality to achieve compliance with set goals. Groundwater remediation by natural flushing allows the natural groundwater movement and geochemical processes to decrease the contaminant concentrations to acceptable levels over a specified period of time. This method is increasingly accepted in areas where the use of groundwater can be temporarily restricted or engineered cleanup methods do not offer particular advantage over the natural processes. The application of technological methods for remediating contaminated groundwaters has to be considered in conjunction with management options such as diversion and development of alternative water sources. The experience with groundwater contamination accrued in IAEA Member States is concentrated in those countries with active uranium mining and milling facilities and nuclear energy programmes. This experience is reported in the Annexes, which include case studies. It

Technical options for the remediation of contaminated groundwater

International Nuclear Information System (INIS)

1999-06-01

This report provides a description of the nature and extent of problems related to radioactive groundwater contamination by outlining the environmental impacts, the sources of contamination and the contaminants of concern radionuclides and their associated contaminants - the main exposure pathways and transport processes and the assessment of risks associated with contaminated groundwater. The main emphasis of this report is on methodologies used in groundwater remediation and available technologies. The methodology section outlines the importance of an initial scoping analysis including the evaluation of uncertainties of the available data and the necessity for defining clear objectives for data collection. This is then followed by comprehensive site characterization, setting of goals and developing alternatives which will be analysed in detail. Available technologies are grouped generally into in situ methods aiming at a containment of the contaminants in place and engineered treatment methods involving an alteration of groundwater flow, quantity and/or quality to achieve compliance with set goals. Groundwater remediation by natural flushing allows the natural groundwater movement and geochemical processes to decrease the contaminant concentrations to acceptable levels over a specified period of time. This method is increasingly accepted in areas where the use of groundwater can be temporarily restricted or engineered cleanup methods do not offer particular advantage over the natural processes. The application of technological methods for remediating contaminated groundwaters has to be considered in conjunction with management options such as diversion and development of alternative water sources. The experience with groundwater contamination accrued in IAEA Member States is concentrated in those countries with active uranium mining and milling facilities and nuclear energy programmes. This experience is reported in the Annexes, which include case studies. It

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

Science.gov (United States)

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

2016-01-01

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.

Electrokinetic remediation of copper mine tailings

DEFF Research Database (Denmark)

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

2007-01-01

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...... 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...

[Study on the groundwater petroleum contaminant remediation by air sparging].

Science.gov (United States)

Wang, Zhi-Qiang; Wu, Qiang; Zou, Zu-Guang; Chen, Hong; Yang, Xun-Chang; Zhao, Ji-Chu

2007-04-01

The groundwater petroleum contaminant remediation effect by air sparging was investigated in an oil field. The results show that the soil geological situation has great influence on the air distribution, and the shape of air distribution is not symmetrical to the air sparging (AS) well as axis. The influence distance in the left of AS well is 6 m, and only 4 m in the right. The petroleum removal rate can reach 70% in the zone with higher air saturation, but only 40% in the zone with lower air saturation, and the average petroleum removal rate reaches 60% in the influence zone for 40 days continuous air sparging. The petroleum components in groundwater were analyzed by GC/MS (gas chromatogram-mass spectrograph) before and after experiments, respectively. The results show that the petroleum removal rate has relationship with the components and their properties. The petroleum components with higher volatility are easily removed by volatilization, but those with lower volatility are difficult to remove, so a tailing effect of lingering residual contaminant exists when the air sparging technology is adopted to treat groundwater contaminated by petroleum products.

Remediation of petroleum hydrocarbons by inoculation with laboratory-cultured microorganisms

International Nuclear Information System (INIS)

Maxwell, C.R.; Baqai, H.A.

1995-01-01

An unauthorized release of gasoline from an underground storage tank (UST) impacted the soil and groundwater beneath a maintenance and fueling capacity. The property owner attempted to remediate the site by inoculating wells screened within the unsaturated and saturated zones with laboratory-cultured microorganisms. The inoculation was a one-time event. No nutrients were added to the subsurface. Air was injected into all inoculation wells during the project to promote aerobic microbial activity. At the first groundwater sampling event after inoculation, concentrations of petroleum hydrocarbon constituents increased inoculation wells. Measurements of dissolved oxygen in the groundwater appeared to indicate that oxygen consumption, and thus hydrocarbon degradation, was not occurring. Visual and olfactory evidence of the groundwater indicated evidence of decaying organic matter. After approximately 1 year and a thorough purging of the inoculation wells, decaying matter disappeared and dissolved oxygen and hydrocarbon concentrations generally returned to preproject levels. Further contaminant reduction did not occur, indicating temporary degradation of water quality as a result of the project and unsuccessful remediation

Sulfate Reduction Remediation of a Metals Plume Through Organic Injection

International Nuclear Information System (INIS)

Phifer, M.A.

2003-01-01

Laboratory testing and a field-scale demonstration for the sulfate reduction remediation of an acidic/metals/sulfate groundwater plume at the Savannah River Site has been conducted. The laboratory testing consisted of the use of anaerobic microcosms to test the viability of three organic substrates to promote microbially mediated sulfate reduction. Based upon the laboratory testing, soybean oil and sodium lactate were selected for injection during the subsequent field-scale demonstration. The field-scale demonstration is currently ongoing. Approximately 825 gallons (3,123 L) of soybean oil and 225 gallons (852 L) of 60 percent sodium lactate have been injected into an existing well system within the plume. Since the injections, sulfate concentrations in the injection zone have significantly decreased, sulfate-reducing bacteria concentrations have significantly increased, the pH has increased, the Eh has decreased, and the concentrations of many metals have decreased. Microbially mediated sulfate reduction has been successfully promoted for the remediation of the acidic/metals/sulfate plume by the injection of soybean oil and sodium lactate within the plume

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…

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

SRS Burial Ground Complex: Remediation in Progress

International Nuclear Information System (INIS)

Griffin, M.; Crapse, B.; Cowan, S.

1998-01-01

Closure of the various areas in the Burial Ground Complex (BGC) represents a major step in the reduction of risk at the Savannah River Site (SRS) and a significant investment of resources. The Burial Ground Complex occupies approximately 195 acres in the central section of the SRS. Approximately 160 acres of the BGC consists of hazardous and radioactive waste disposal sites that require remediation. Of these source acres, one-third have been remediated while two-thirds are undergoing interim or final action. These restoration activities have been carried out in a safe and cost effective manner while minimizing impact to operating facilities. Successful completion of these activities is in large part due to the teamwork demonstrated by the Department of Energy, contractor/subcontractor personnel, and the regulatory agencies. The experience and knowledge gained from the closure of these large disposal facilities can be used to expedite closure of similar facilities

Arsenic Remediation by Synthetic and Natural Adsorbents

Directory of Open Access Journals (Sweden)

Muhammad Saqaf Jagirani

2017-06-01

Full Text Available The contagion of toxic metals in water is a serious environmental and health concern and threatening problem worldwide. Particularly arsenic contamination in ground water has became great dilemma in the earlier decades. With advent in research for arsenic remediation, standard of drinking water is improving and now reduced to few parts per million (ppm level of arsenic in drinking water sources. However, due to continuous enhancement in environmental pollution, remediation techniques are still needed to achieve the drinking water quality standard. Development of novel and economically feasible removal techniques or materials for selective separation of this toxic specie has been the main focus of research. Several arsenic removal techniques, including membrane separation, coagulation, precipitation, anion exchange have been developed. The aim of this article is to review briefly arsenic chemistry and previous and current available technologies that have been reported various low-cost adsorbents for arsenic removal.

Characterization of radioactively contaminated sites for remediation purposes

International Nuclear Information System (INIS)

1998-05-01

Characterization of the contaminated site is essential before embarking on a programme for its remediation and ultimate restoration. Reliable and suitable data must be obtained regarding the distribution and physical, chemical and nuclear properties of all radioactive contaminants. Characterization data is necessary for assessing the associated radiation risks and is used in support of the required engineering design and project planning for the environmental restoration. In addition, continuing characterization can provide information regarding efficiency of the cleanup methods and influence possible redirection of work efforts. Similarly, at the end of the remediation phase, characterization and ongoing monitoring can be used to demonstrate completion and success of the cleanup process. The suggested methodology represents a contribution attempting to solve the issue of preremediation characterization in a general manner. However, a number of difficulties might make this methodology unsuitable for general application across the diverse social, environmental and political systems in the IAEA Member States. This TECDOC covers the methodologies used to characterize radioactively contaminated sites for the purpose of remediating the potential sources of radiation exposure and assessing the hazards to human health and the environment

Sustainable Remediation for Enhanced NAPL Recovery from Groundwater

Science.gov (United States)

Javaher, M.

2012-12-01

Sustainable remediation relates to the achievement of balance between environmental, social, and economic elements throughout the remedial lifecycle. A significant contributor to this balance is the use of green and sustainable technologies which minimize environmental impacts, while maximizing social and economic benefits of remedial implementation. To this end, a patented mobile vapor energy generation (VEG) technology has been developed targeting variable applications, including onsite soil remediation for unrestricted reuse and enhanced non-aqueous phase liquid (NAPL) recover at the water table. At the core of the mobile VEG technology is a compact, high efficiency vapor generator, which utilizes recycled water and propane within an entirely enclosed system to generate steam as high as 1100°F. Operating within a fully enclosed system and capturing all heat that is generated within this portable system, the VEG technology eliminates all emissions to the atmosphere and yields an undetected carbon footprint with resulting carbon dioxide concentrations that are below ambient levels. Introduction of the steam to the subsurface via existing wells results in a desired change in the NAPL viscosity and the interfacial tension at the soil, water, NAPL interface; in turn, this results in mobilization and capture of the otherwise trapped, weathered NAPL. Approved by the California Air Resources Control Board (and underlying Air Quality Management Districts) and applied in California's San Joaquin Valley, in-well heating of NAPLs trapped at the water table using the VEG technology has proven as effective as electrical resistivity heating (ERH) in changing the viscosity of and mobilizing NAPLs in groundwater in support of recovery, but has achieved these results while minimizing the remedial carbon footprint by 90%, reducing energy use by 99%, and reducing remedial costs by more than 95%. NAPL recovery using VEG has also allowed for completion of source removal historically

Effectiveness of remediation of metal-contaminated mangrove sediments (Sydney estuary, Australia).

Science.gov (United States)

Birch, Gavin; Nath, Bibhash; Chaudhuri, Punarbasu

2015-04-01

Industrial activities and urbanization have had a major consequence for estuarine ecosystem health and water quality globally. Likewise, Sydney estuary has been significantly impacted by widespread, poor industrial practices in the past, and remediation of legacy contaminants have been undertaken in limited parts of this waterway. The objective of the present investigation was to determine the effectiveness of remediation of a former Pb-contaminated industrial site in Homebush Bay on Sydney estuary (Australia) through sampling of inter-tidal sediments and mangrove (Avicennia marina) tissue (fine nutritive roots, pneumatophores, and leaves). Results indicate that since remediation 6 years previously, Pb and other metals (Cu, Ni and Zn) in surficial sediment have increased to concentrations that approach pre-remediation levels and that they were considerably higher than pre-settlement levels (3-30 times), as well as at the reference site. Most metals were compartmentalized in fine nutritive roots with bio-concentration factors greater than unity, while tissues of pneumatophores and leaves contained low metal concentrations. Lead concentrations in fine nutritive root, pneumatophore, and leaf tissue of mangroves from the remediated site were similar to trees in un-remediated sites of the estuary and were substantially higher than plants at the reference site. The situation for Zn in fine nutritive root tissue was similar. The source of the metals was either surface/subsurface water from the catchment or more likely remobilized contaminated sediment from un-remediated parts of Homebush Bay. Results of this study demonstrate the problems facing management in attempting to reduce contamination in small parts of a large impacted area to concentrations below local base level.

Herbal remedies and aroma for beauty and health

Directory of Open Access Journals (Sweden)

Тетяна Петрівна Гарник

2015-11-01

Full Text Available Recently, non-medical, naturopathic methods remedies for prevention and treatment, including aromatherapy and phytotherapy, become more developed and perfect. Aromatherapy is one of phytotherapy methods using natural organic volatile aromatic substances of plants - essential oils. When used correctly they are comfortable, painless, and affordable remedies, affecting all systems and organs, allowing get over diseases, skin damage and possible mental disorders.Aim. The aim of our research was the literature data analysis, and our own study concerning the application of phytotherapeutic and aromatic remedies for skin and hair care, as well as for complex, rehabilitation and preventive treatment of respiratory diseases, musculoskeletal system disorders, cardiovascular system and increase work capacity.Methods. To solve the problem conventional analytical research of electronic and paper sources, as well as our own studies analysis, were used.Results. Based on the analysis of the literature data and our own studies, the effective phytotherapeutic remedies for different types of skin and hair care using different species of available herbal material and natural essential oils.The attention was focused on essential oils quality evaluation criteria suitable for medical use, and methods of their use for both children and adults.Conclusion. The essential oils lists explained from the scientific point of view were displayed for prevention and treatment of respiratory diseases, musculoskeletal system disorders, emotional state regulation, and during working on the computer, as well as elimination of cosmetic skin blemishes and premature ageing of the skin

Soil remediation of a former power plant site in Tulita, Northwest Territories

International Nuclear Information System (INIS)

Pouliot, Y.; Thomassin-Lacroix, E.; Moreau, N.

2005-01-01

This paper outlines major stages of an ongoing remediation project caused by a power generating plant in the Dene Hamlet of Tulita. High levels of soil contamination were caused by the plant's operations as well as accidental petroleum hydrocarbon (PHC) spills. The decommissioning of the plant required that the site be remediated. Challenges faced by the remediators included the high level of contamination, the remote location of the community, as well as the fact that the site was located in the centre of the community. In addition, the soil in the impacted site was fine, and a 20 cm thick layer of peat acted as sponge, absorbing and trapping hydrocarbons. Remedial criteria was outlined according to Canada-Wide Standards for fine-grained soil in an industrial setting. The technology used for the project was Biopile, a process consisting of installing wells in the contaminated zone in order to provide the aeration required for PHC biodegradation and to condition the soil on a regular basis in order to promote optimal treatment conditions throughout the impacted material. Results indicated that the first 2 months were successful in reducing initial PHC levels. However, the following treatment season did not show as much degradation. An investigation revealed that nitrogen and phosphorus levels were insufficient to sustain microbial activity, as a result of lower than normal temperatures in the area for that season. Nutrients were added to the soil to re-establish the appropriate treatment conditions. It was concluded that the technology used presented numerous advantages. Overall disturbance of the area was reduced, and allowed other measures to be implemented, including segregation of the highly impacted peat layer. It was expected that remediation objectives for the entire site will be met by July 2005. 3 refs., 3 tabs

Soil remediation of a former power plant site in Tulita, Northwest Territories

Energy Technology Data Exchange (ETDEWEB)

Pouliot, Y.; Thomassin-Lacroix, E. [Biogenie Inc., Lachenaie, PQ (Canada); Moreau, N. [Biogenie, Quebec City, PQ (Canada)

2005-07-01

This paper outlines major stages of an ongoing remediation project caused by a power generating plant in the Dene Hamlet of Tulita. High levels of soil contamination were caused by the plant's operations as well as accidental petroleum hydrocarbon (PHC) spills. The decommissioning of the plant required that the site be remediated. Challenges faced by the remediators included the high level of contamination, the remote location of the community, as well as the fact that the site was located in the centre of the community. In addition, the soil in the impacted site was fine, and a 20 cm thick layer of peat acted as sponge, absorbing and trapping hydrocarbons. Remedial criteria was outlined according to Canada-Wide Standards for fine-grained soil in an industrial setting. The technology used for the project was Biopile, a process consisting of installing wells in the contaminated zone in order to provide the aeration required for PHC biodegradation and to condition the soil on a regular basis in order to promote optimal treatment conditions throughout the impacted material. Results indicated that the first 2 months were successful in reducing initial PHC levels. However, the following treatment season did not show as much degradation. An investigation revealed that nitrogen and phosphorus levels were insufficient to sustain microbial activity, as a result of lower than normal temperatures in the area for that season. Nutrients were added to the soil to re-establish the appropriate treatment conditions. It was concluded that the technology used presented numerous advantages. Overall disturbance of the area was reduced, and allowed other measures to be implemented, including segregation of the highly impacted peat layer. It was expected that remediation objectives for the entire site will be met by July 2005. 3 refs., 3 tabs.

Nitrate and Nitrogen Oxides: Sources, Health Effects and Their Remediation.

Science.gov (United States)

Hakeem, Khalid Rehman; Sabir, Muhammad; Ozturk, Munir; Akhtar, Mohd Sayeed; Ibrahim, Faridah Hanum

Increased use of nitrogenous (N) fertilizers in agriculture has significantly altered the global N-cycle because they release nitrogenous gases of environmental concerns. The emission of nitrous oxide (N 2 O) contributes to the global greenhouse gas accumulation and the stratospheric ozone depletion. In addition, it causes nitrate leaching problem deteriorating ground water quality. The nitrate toxicity has been reported in a number of studies showing the health hazards like methemoglobinemia in infants and is a potent cause of cancer. Despite these evident negative environmental as well as health impacts, consumption of N fertilizer cannot be reduced in view of the food security for the teeming growing world population. Various agronomic and genetic modifications have been practiced to tackle this problem. Some agronomic techniques adopted include split application of N, use of slow-release fertilizers, nitrification inhibitors and encouraging the use of organic manure over chemical fertilizers. As a matter of fact, the use of chemical means to remediate nitrate from the environment is very difficult and costly. Particularly, removal of nitrate from water is difficult task because it is chemically non-reactive in dilute aqueous solutions. Hence, the use of biological means for nitrate remediation offers a promising strategy to minimize the ill effects of nitrates and nitrites. One of the important goals to reduce N-fertilizer application can be effectively achieved by choosing N-efficient genotypes. This will ensure the optimum uptake of applied N in a balanced manner and exploring the molecular mechanisms for their uptake as well as metabolism in assimilatory pathways. The objectives of this paper are to evaluate the interrelations which exist in the terrestrial ecosystems between the plant type and characteristics of nutrient uptake and analyze the global consumption and demand for fertilizer nitrogen in relation to cereal production, evaluate the various

International cooperation and support in environmental remediation - is there any room for improvement?

Science.gov (United States)

Fernandes, Horst Monken; Recio, Manuel Santamaria; Forsstrom, Hans; Carson, Philip Michael

2013-05-01

The challenges faced by states seeking to implement Environmental Remediation works are many. To this end, the International Atomic Energy Agency attempts to provide assistance and guidance to Member States wherever possible. This review article provides a brief overview of these challenges and highlights the international sources of financial and implementation support discussed at an international conference on the topic in Astana, Kazakhstan in 2009. The conference concluded the importance of institutional structures as a pre-requisite for remediation work, recognized privatization as a useful but limited financing tool for remediation and illustrated the need for better coordination between international funding organizations to reduce overlap and optimization of resources to secure the best outcomes. Copyright © 2011 Elsevier Ltd. All rights reserved.

(Bio-)remediation of VCHC contaminants in a Technosol under unsaturated conditions.

Science.gov (United States)

Baumgarten, W; Fleige, H; Peth, S; Horn, R

2013-07-01

The remediation of dense non-aqueous phase liquids has always been a concern of both public and scientific interest groups. In this research work a modified physical concept of (bio)remediation of a volatile chlorinated hydrocarbon (VCHC) contamination was elaborated under laboratory conditions and modeled with HYDRUS-2D. In field dechlorination is influenced by both physicochemical and hydraulic properties of the substrate, e.g. texture, pore size distribution, pore liquid characteristics, e.g. viscosity, pH, surface tension, and dependent on the degree of saturation of the vadose zone. Undisturbed soil cores (100 cm³) were sampled from a Spolic Technosol. Considering hydraulic properties and functions, unsaturated percolation was performed with vertically and horizontally structured samples. VCHC concentrations were calculated prior, during, and after each percolation cycle. According to laboratory findings, microemulsion showed the most efficient results with regard to flow behavior in the unsaturated porous media and its accessibility for bacteria as nutrient. The efficiency of VCHC remediation could be increased by the application of a modified pump-and-treat system: the injection of bacteria Dehalococcoides ethanogenes with microemulsion, and extraction at a constant matric potential level of -6 kPa. Achieved data was used for HYDRUS-2D simulations, modeling in situ conditions, demonstrating the practical relevance (field scale) of performed unsaturated percolation (core scale), and in order to exclude capillary barrier effects.

Award of merit: transportable remediation unit -Jacques Whitford Environment Limited -Toronto

International Nuclear Information System (INIS)

Anon.

1995-01-01

A unique hybrid of remediation technologies was designed to deal with the problem of removing the gasoline and fuel-oil found in soils and groundwater as a result of spills or leakage at petroleum storage and dispensing facilities. Liquid petroleum hydrocarbons were found discharging into a creek in a residential and commercial neighborhood of Metropolitan Toronto. Numerous in-place soil and ground water remediation approaches were evaluated in the course of searching for a solution. A full-scale, transportable, in-situ bioslurping remediation unit was recommended. The unit was connected to 13 specially designed vertical bioslurping wells, and to a buried horizontal header network comprised of four separate zones that could be used to simultaneously extract and/or inject air and water flows. Cycling of various modes of operation was based on detailed monitoring and analysis, which allowed for optimal recovery and biological degradation of contaminants. After only four months of operation, over 4000 kg of petroleum hydrocarbon contaminants had been removed and treated, and all of the mobile liquid hydrocarbons at the water table had been removed. Treatment cost was estimated at $100 to $120 per tonne of contaminated soil, but assuming that the unit could be used at more than one site, the net treatment cost would decrease to $20 to $30 per tonne. 1 ill

Development of subsurface characterization method for decommissioning site remediation

Energy Technology Data Exchange (ETDEWEB)

Hong, Sang Bum; Nam, Jong Soo; Choi, Yong Suk; Seo, Bum Kyoung; Moon, Jei Kwon; Choi, Jong Won [KAERI, Daejeon (Korea, Republic of)

2016-05-15

In situ measurement of peak to valley method based on the ratio of counting rate between the full energy peak and Compton region was applied to identify the depth distribution of 137Cs. The In situ measurement and sampling results were applied to evaluate a residual radioactivity before and after remediation in decommissioning KRR site. Spatial analysis based on the Geostatistics method provides a reliable estimating the volume of contaminated soil with a graphical analysis, which was applied to the site characterization in the decommissioning KRR site. The in situ measurement and spatial analysis results for characterization of subsurface contamination are presented. The objective of a remedial action is to reduce risks to human health to acceptable levels by removing the source of contamination. Site characterization of the subsurface contamination is an important factor for planning and implementation of site remediation. Radiological survey and evaluation technology are required to ensure the reliability of the results, and the process must be easily applied during field measurements. In situ gamma-ray spectrometry is a powerful method for site characterization that can be used to identify the depth distribution and quantify radionuclides directly at the measurement site. The in situ measurement and Geostatistics method was applied to the site characterization for remediation and final status survey in decommissioning KRR site.

The innovative application of surface geophysical techniques for remedial investigations

Energy Technology Data Exchange (ETDEWEB)

Saunders, W.R. [OYO Geospace, Fort Myers, FL (United States); Smith, S. [ICF Kaiser Engineers, Boston, MA (United States); Gilmore, P. [Fishbeck, Thomson, Carr and Huber, Aida, MI (United States); Cox, S. [Blasland, Bouck, and Lee, Edison, NJ (United States)

1993-03-01

When researchers are investigating potential subsurface contamination at hazardous waste landfills, the surface geophysical techniques they may use are often limited. Many geophysical surveys are concerned with areas next to and not directly within the landfill units. The highly variable properties of the materials within the landfill may result in geophysical data that are either difficult or impossible to interpret. Therefore, contamination at these sites may not be detected until substantial lateral migration away from the unit has occurred. In addition, because of the poor resolution of some techniques, the landfill as a whole must be considered as a source, where discrete disposal areas within landfill units may be the actual point sources of contaminants. In theory, if specific sources within the landfill are identified and isolated, then reduced time, effort, and expenditures will be required for remediation activities. In the summer of 1989, the Idaho National Engineering Laboratory (INEL) investigated a small potentially hazardous waste landfill to determine if contaminant hot spots could be identified within the landfill and to determine if significant vertical and lateral migration of contaminants was occurring away from these locations. Based on the present hydrogeologic conditions, researchers anticipated that subsurface flow would be primarily vertical, with the zone of saturation at a depth greater than 150 meters. This necessitated that the survey be performed, for the most part, directly on the capped portion of the landfill. Focused geophysical surveys conducted off the landfill would not have provided useful information concerning conditions directly beneath the landfill. This paper discusses the planning, application, and analysis of four combined sensing methods: two methods of electromagnetic induction [low induction (Em) and time domain (TEM)], ground penetrating radar (GPR), and soil gas.

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

Instrumentation for coastal zone management

Digital Repository Service at National Institute of Oceanography (India)

Joseph, A.

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Management of coastal zone vegetation

Digital Repository Service at National Institute of Oceanography (India)

Untawale, A.G.

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Rolled lawn as tool for industrial barren remediation

Science.gov (United States)

Gorbacheva, T. T.; Ivanova, L. A.; Kikuchi, R.; Gerardo, R.

2009-04-01

Fast development of the industrial and urban territories during last century has led to great disturbance of natural ecosystems in a lot of regions of the world. In the Far North the risk resulted from technogenic influence involves essentially more expressed negative consequences for the nature comparing to a regions of averages and southern latitudes due to higher sensitivity of northern ecosystems. Since thirtieth years of last century industrial complexes on extraction and processing of nonferrous metals ores are functioned on Kola peninsula territory. They are powerful sources of emissions of acidifying substances and heavy metals. Long term influence of these emissions resulted in deep degradation of terrestrial ecosystems up to industrial barren arising in immediate proximity to industrial centre Monchegorsk. The most radical way of disturbed territories rehabilitation is biological remediation. In 2006-2008 innovative methods of high-quality grass cover performance was developed in local enterprise «VIPON» in Apatity. Vermiculite trademark «VIPON» is characterized by not broken structure of minerals combined with week reactance, high mechanical durability, favorable рН equal 6.5-7.0, valuable absorptive and ion exchange properties. Final product of proposed technology was rolled lawn which successfully applied for remediation of disturbed sites in urban territories as such as industrial plots with low contamination. One of abstract authors namely L.Ivanova is one of technology implementators. During 2008 the field test was performed near the smelter complex (67°51'N, 32°48'E) to estimate suitability of proposed method for site remediation in more severe conditions such as in industrial barren. The method is based on cultivation of perennial grasses using hydroponics with thermally inflated vermiculite from local deposit (Kovdor) followed by rolled lawn placement on very contaminated sites near Monchegorsk. Great advantage of rolled lawn is short

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…

Object reasoning for waste remediation

International Nuclear Information System (INIS)

Pennock, K.A.; Bohn, S.J.; Franklin, A.L.

1991-08-01

A large number of contaminated waste sites across the United States await size remediation efforts. These sites can be physically complex, composed of multiple, possibly interacting, contaminants distributed throughout one or more media. The Remedial Action Assessment System (RAAS) is being designed and developed to support decisions concerning the selection of remediation alternatives. The goal of this system is to broaden the consideration of remediation alternatives, while reducing the time and cost of making these considerations. The Remedial Action Assessment System is a hybrid system, designed and constructed using object-oriented, knowledge- based systems, and structured programming techniques. RAAS uses a combination of quantitative and qualitative reasoning to consider and suggest remediation alternatives. The reasoning process that drives this application is centered around an object-oriented organization of remediation technology information. This paper describes the information structure and organization used to support this reasoning process. In addition, the paper describes the level of detail of the technology related information used in RAAS, discusses required assumptions and procedural implications of these assumptions, and provides rationale for structuring RAAS in this manner. 3 refs., 3 figs

Tree Coring as a Complement to Soil Gas Screening to Locate PCE and TCE Source Zones and Hot Spots

DEFF Research Database (Denmark)

Nielsen, Mette Algreen; Trapp, Stefan; Rehne Jensen, Pernille

2015-01-01

) or trichloroethylene (TCE) to evaluate their ability to locate source zones and contaminant hot spots. One test site represented a relatively homogeneous sandy soil and aquifer, and the second a more heterogeneous geology with both sandy and less permeable clay till layers overlying a chalk aquifer. Tree cores from...

Advanced Neutron Source Reactor zoning, shielding, and radiological optimization guide

International Nuclear Information System (INIS)

Westbrook, J.L.; DeVore, J.R.

1995-08-01

In the design of major nuclear facilities, it is important to protect both humans and equipment excessive radiation dose. Past experience has shown that it is very effective to apply dose reduction principles early in the design of a nuclear facility both to specific design features and to the manner of operation of the facility, where they can aid in making the facility more efficient and cost-effective. Since the appropriate choice of radiological controls and practices varies according to the case, each area of the facility must be analyzed for its radiological impact, both by itself and in interactions with other areas. For the Advanced Neutron Source (ANS) project, a large relational database will be used to collect facility information by system and relate it to areas. The database will also hold the facility dose and shielding information as it is produced during the design process. This report details how the ANS zoning scheme was established and how the calculation of doses and shielding are to be done

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.

Experimental Plan: 300 Area Treatability Test: In Situ Treatment of the Vadose Zone and Smear Zone Uranium Contamination by Polyphosphate Infiltration

International Nuclear Information System (INIS)

Wellman, Dawn M.; Pierce, Eric M.; Oostrom, Mart; Fruchter, Jonathan S.

2007-01-01

The overall objectives of the treatability test is to evaluate and optimize polyphosphate remediation technology for infiltration either from ground surface, or some depth of excavation, providing direct stabilization of uranium within the deep vadose and capillary fringe above the 300 Area aquifer. Expected result from this experimental plan is a data package that includes: (1) quantification of the retardation of polyphosphate, (2) the rate of degradation and the retardation of degradation products as a function of water content, (3) an understanding of the mechanism of autunite formation via the reaction of solid phase calcite-bound uranium and aqueous polyphosphate remediation technology, (4) an understanding of the transformation mechanism, identity of secondary phases, and the kinetics of the reaction between uranyl-carbonate and silicate minerals with the polyphosphate remedy under solubility-limiting conditions, (5) quantification of the extent and rate of uranium released and immobilized based on the infiltration rate of the polyphosphate remedy and the effect of and periodic wet-dry cycling on the efficacy of polyphosphate remediation for uranium in the vadose zone and capillary fringe, and (6) quantification of reliable equilibrium solubility values for autunite under hydraulically unsaturated conditions allowing accurate prediction of the long-term stability of autunite. Moreover, results of intermediate scale testing will quantify the transport of polyphosphate and degradation products, and yield degradation rates, at a scale that is bridging the gap between the small-scale UFA studies and the field scale. These results will be used to test and verify a site-specific, variable saturation, reactive transport model and to aid in the design of a pilot-scale field test of this technology. In particular, the infiltration approach and monitoring strategy of the pilot test would be primarily based on results from intermediate-scale testing. Results from this

Air-Based Remediation Workshop - Section 8 Air-Based Remediation Technology Selection Logic

Science.gov (United States)

Pursuant to the EPA-AIT Implementing Arrangement 7 for Technical Environmental Collaboration, Activity 11 "Remediation of Contaminated Sites," the USEPA Office of International Affairs Organized a Forced Air Remediation Workshop in Taipei to deliver expert training to the Environ...

Passive remediation of chlorinated volatile organic compounds using barometric pumping

International Nuclear Information System (INIS)

Rossabi, J.; Looney, B.B.; Dilek, C.A.E.; Riha, B.; Rohay, V.J.

1993-01-01

The purpose of the Savannah River Integrated Demonstration Program, sponsored by the Department of Energy, is to demonstrate new subsurface characterization, monitoring, and remediation technologies. The interbedded clay and sand layers at the Integrated Demonstration Site (IDS) are contaminated with chlorinated volatile organic compounds (CVOCs). Characterization studies show that the bulk of the contamination is located in the approximately 40 m thick vadose zone. The most successful strategy for removing contaminants of this type from this environment is vapor extraction alone or in combination with other methods such as air sparging or enhanced bioremediation. Preliminary work at the IDS has indicated that natural pressure differences between surface and subsurface air caused by surface barometric fluctuations can produce enough gas flow to make barometric pumping a viable method for subsurface remediation. Air flow and pressure were measured in wells that are across three stratigraphic intervals in the vadose zone' The subsurface pressures were correlated to surface pressure fluctuations but were damped and lagging in phase corresponding to depth and stratum permeability. Piezometer wells screened at lower elevations exhibited a greater phase lag and damping than wells screened at higher elevations where the pressure wave from barometric fluctuations passes through a smaller number of low permeable layers. The phase lag between surface and subsurface pressures results in significant fluxes through these wells. The resultant air flows through the subsurface impacts CVOC fate and transport. With the appropriate controls (e.g. solenoid valves) a naturally driven vapor extraction system can be implemented requiring negligible operating costs yet capable of a large CVOC removal rate (as much as 1--2 kg/day in each well at the IDS)

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

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...... possibilities. Genealogists use their private websites to negotiate family identity and hereby create a sense of belonging in an increasingly complex society. Digital technologies enhance the possibilities of coorporation between genealogists. Therefore, the websites are also used to present archival...

An Approach Using Gas Monitoring to Find the Residual TCE Location in the Unsaturated Zone of Woosan Industrial Complex (WIC), Korea

Science.gov (United States)

Koh, Y.; Lee, S.; Yang, J.; Lee, K.

2012-12-01

An area accommodating various industrial facilities has fairly high probability of groundwater contamination with multiple chlorinated solvents such as trichloroethene (TCE), carbon tetrachloride (CT), and chloroform (CF). Source tracing of chlorinated solvents in the unsaturated zone is an essential procedure for the management and remediation of contaminated area. From the previous study on seasonal variations in hydrological stresses and spatial variations in geologic conditions on a TCE plume, the existence of residual DNAPLs at or above the water table has proved. Since TCE is one of the frequently detected VOCs (Volatile Organic Compounds) in groundwater, residual TCE can be detected by gas monitoring. Therefore, monitoring of temporal and spatial variations in the gas phase TCE contaminant at an industrial complex in Wonju, Korea, were used to find the residual TCE locations. As pilot tests, TCE gas samples collected in the unsaturated zone at 4 different wells were analyzed using SPME (Solid Phase MicroExtraction) fiber and Gas Chromatography (GC). The results indicated that detecting TCE in gas phase was successful from these wells and TCE analysis on gas samples, collected from the unsaturated zone, will be useful for source area characterization. However, some values were too high to doubt the accuracy of the current method, which needs a preliminary lab test with known concentrations. The modified experiment setups using packer at different depths are in process to find residual TCE locations in the unsaturated zone. Meanwhile, several PVD (polyethylene-membrane Passive Vapor Diffusion) samplers were placed under water table to detect VOCs by equilibrium between air in the vial and VOCs in pore water.

MICHIGAN SOIL VAPOR EXTRACTION REMEDIATION (MISER) MODEL: A COMPUTER PROGRAM TO MODEL SOIL VAPOR EXTRACTION AND BIOVENTING OF ORGANIC CHEMICALS IN UNSATURATED GEOLOGICAL MATERIAL

Science.gov (United States)

Soil vapor extraction (SVE) and bioventing (BV) are proven strategies for remediation of unsaturated zone soils. Mathematical models are powerful tools that can be used to integrate and quantify the interaction of physical, chemical, and biological processes occurring in field sc...

Background report for the uranium-mill-tailings-sites remedial-action program

International Nuclear Information System (INIS)

1981-04-01

The Uranium Mill Tailings Radiation Control Act of 1978, Public Law 95-604, mandates remedial action responsibilities to the Department of Energy for designated inactive uranium processing sites. To comply with the mandates of the Act, a program to survey and evaluate the radiological conditions at inactive uranium processing sites and at vicinity properties containing residual radioactive material derived from the sites is being conducted; the Remedial Action Program Office, Office of the Assistant Secretary for Nuclear Energy is implementing remedial actions at these processing sites. This report provides a brief history of the program, a description of the scope of the program, and a set of site-specific summaries for the 22 locations specified in the Act and three additional locations designated in response to Federal Register notices issued on August 17 and September 5, 1979. It is designed to be a quick source of background information on sites covered by the implementation program for Public Law 95-604

The phyto-remediation of radioactively contaminated land - a feasible approach or just bananas?

International Nuclear Information System (INIS)

Nesbitt, Victoria A

2013-01-01

Soil is an essential component of all terrestrial ecosystems and is under increasing threat from human activity. Techniques available for removing radioactive contamination from soil and aquatic substrates are limited and often costly to implement; particularly over large areas. Frequently, bulk soil removal, with its attendant consequences, is a significant component of the majority of contamination incidents. Alternative techniques capable of removing contamination or exposure pathways without damaging or removing the soil are therefore of significant interest. An increasing number of old nuclear facilities are entering 'care and maintenance', with significant ground contamination issues. Phyto-remediation - the use of plants' natural metabolic processes to remediate contaminated sites is one possible solution. Its key mechanisms include phyto-extraction and phyto-stabilisation. These are analogues of existing remedial techniques. Further, phyto-remediation can improve soil quality and stability and restore functionality. Information on the application of phyto-remediation in the nuclear industry is widely distributed over an extended period of time and sources. It is therefore difficult to quickly and effectively identify which plants would be most suitable for phyto-remediation on a site by site basis. In response, a phyto-remediation tool has been developed to address this issue. Existing research and case studies were reviewed to understand the mechanisms of phyto-remediation, its effectiveness and the benefits and limitations of implementation. The potential for cost recovery from a phyto-remediation system is also briefly considered. An overview of this information is provided here. From this data, a set of matrices was developed to guide potential users through the plant selection process. The matrices take the user through a preliminary screening process to determine whether the contamination present at their site is amenable to phyto-remediation

Mold: Cleanup and Remediation

Science.gov (United States)

... National Center for Environmental Health (NCEH) Cleanup and Remediation Recommend on Facebook Tweet Share Compartir On This ... CDC and EPA on mold cleanup, removal and remediation. Cleanup information for you and your family Homeowner’s ...

Fiscal Year 2007 Phased Construction Completion Report for the Zone 2 Soils, Slabs, and Subsurface Structures at East Tennessee Technology Park, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

RSI

2008-03-01

The purpose of this Phased Construction Completion Report (PCCR) is to present the fiscal year (FY) 2007 results of characterization activities and recommended remedial actions (RAs) for 11 exposure units (EUs) in Zone 2 (Z2-01, Z2-03, Z2-08, Z2-23, Z2-24, Z2-28, Z2-34, Z2-37, Z2-41, Z2-43, and Z2-44) at the East Tennessee Technology Park (ETTP), which is located in the northwest corner of the U.S. Department of Energy (DOE) Oak Ridge Reservation in Oak Ridge, Tennessee (Fig. 1). ETTP encompasses a total land area of approximately 5000 acres that has been subdivided into three zones--Zone 1 ({approx}1400 acres), Zone 2 ({approx}800 acres), and the Boundary Area ({approx}2800 acres). Zone 2, which encompasses the highly industrialized portion of ETTP shown in Fig. 1, consists of all formerly secured areas of the facility, including the large processing buildings and direct support facilities; experimental laboratories and chemical and materials handling facilities; materials storage and waste disposal facilities; secure document records libraries; and shipping and receiving warehouses. The Zone 2 Record of Decision for Soil, Buried Waste, and Subsurface Structure Actions in Zone 2, East Tennessee Technology Park, Oak Ridge, Tennessee (DOE 2005) (Zone 2 ROD) specifies the future end use for Zone 2 acreage as uncontrolled industrial for the upper 10 ft of soils. Characterization activities in these areas were conducted in compliance with the Zone 2 ROD and the Dynamic Verification Strategy (DVS) and data quality objectives (DQOs) presented in the Remedial Design Report/Remedial Action Work Plan for Zone 2 Soils, Slabs, and Subsurface Structures, East Tennessee Technology Park, Oak Ridge, Tennessee (DOE 2007) (Zone 2 RDR/RAWP). The purpose of this PCCR is to address the following: (1) Document DVS characterization results for the accessible EUs in FY 2007; (2) Describe and document the risk evaluation for each EU, and determine if the EU met the Zone 2 ROD requirements

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.

Long term performance of different radon remedial methods in Sweden

CERN Document Server

Clavensjoe, B

2002-01-01

The object of this project was to investigate the long time effectiveness of different radon remedial methods. The ten years project started 1991. From start the investigation comprised of 105 dwellings (91 single-family houses and 14 flats in multi-family buildings). In all of the dwellings remedial measures were carried out in the eighties. Before and immediately after the reduction the local measured the radon concentrations. New measurements of the radon concentrations have been made every third year; in 1991, 1994, 1997 and in 2000. Twelve different radon remedial methods and method combinations were used. The radon sources were building materials as well as sub-soils. In all of the dwellings the radon concentrations were measured by nuclear track films during 3 months (January-March) measurements and in half of them the air change rates by passive tracer gas methods. The results of the 2000 and the 1991 (within brackets) studies showed that the radon concentration was up to 200 Bq/m sup 3 in 54 (54) sin...

Reasons for increasing radon concentrations in radon remediated houses

International Nuclear Information System (INIS)

Clavensjoe, B.

1997-01-01

The study comprises 31 single-dwelling houses where remedial actions were carried out in the 1980s. In all of them the radon concentrations have increased more than 30% according to recent control measurements. Radon sources are building material as well as the soil. The remedial actions dealt with ventilation systems, leakage through the basement floor, air cushions, sub-slab suction or radon wells according to the original problems. Causes for the increase varied: In many houses with soil radon problems, the installation of a normal mechanical ventilation system is not a good remedial action. In some houses on a ground with high permeability and high radon content in the soil air, the radon concentration may increase by the lowering of the indoor air pressure. In other houses the increase was a measurement effect, where sites/rooms were confused. Living related causes were identified in a number of cases, where fan speeds were reduced for energy conservation/noise reduction purposes or different use of windows airing had occurred. Extension of the dwelling space without changing the ventilation system caused the increase in one house. 23 refs

Strategy paper. Remedial design/remedial action 100 Area. Revision 1

International Nuclear Information System (INIS)

Donahoe, R.L.

1995-07-01

The purpose of this planning document is to identify and define the approach for remedial design and remedial action (RD/RA) in the 100 Area of the Hanford Site, located in southeastern Washington State. Additionally, this document will support the Hanford Site Environmental Restoration Contract (ERC) team, the US Department of Energy (DOE), and regulatory agencies in identifying and agreeing upon the complete process for expedited cleanup of the 100 Area

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....

MGP site remediation: Working toward presumptive remedies

International Nuclear Information System (INIS)

Larsen, B.R.

1996-01-01

Manufactured Gas Plants (MGPs) were prevalent in the United States during the 19th and first half of the 20th centuries. MGPs produced large quantities of waste by-products, which varied depending on the process used to manufacture the gas, but most commonly were tars and polynuclear aromatic hydrocarbons. There are an estimated 3,000 to 5,000 abandoned MGP sites across the United States. Because these sites are not concentrated in one geographic location and at least three different manufacturing processes were used, the waste characteristics are very heterogeneous. The question of site remediation becomes how to implement a cost-effective remediation with the variety of cleanup technologies available for these sites. Because of the significant expenditure required for characterization and cleanup of MGP sites, owners and regulatory agencies are beginning to look at standardizing cleanup technologies for these sites. This paper discusses applicable cleanup technologies and the attitude of state regulatory agencies towards the use of presumptive remedies, which can reduce the amount of characterization and detailed analysis necessary for any particular site. Additionally, this paper outlines the process of screening and evaluating candidate technologies, and the progress being made to match the technology to the site

Site remediation: The naked truth

International Nuclear Information System (INIS)

Calloway, J.M.

1991-01-01

The objective of any company faced with an environmental site remediation project is to perform the cleanup effectively at the lowest possible cost. Today, there are a variety of techniques being applied in the remediation of sites involving soils and sludges. The most popular include: stabilization, incineration, bioremediation and off-site treatment. Dewatering may also play an integral role in a number of these approaches. Selecting the most cost-effective technique for remediation of soils and sludges can be a formidable undertaking, namely because it is often difficult to quantify certain expenses in advance of the project. In addition to providing general cost guidelines for various aspects of soil and sludge remediation, this paper will show how some significant cost factors can be affected by conditions related to specific remediation projects and the cleanup technology being applied

Remediation using trace element humate surfactant

Energy Technology Data Exchange (ETDEWEB)

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.

Remedial action and waste disposal project: 100-B/C remedial action readiness evaluation plan

International Nuclear Information System (INIS)

April, J.G.; Bryant, D.L.; Cislo, G.B.

1996-06-01

The Readiness Evaluation Plan presents the methodology used to assess the readiness of the 100-B/C Remedial Action Project. The 100 Areas Remedial Action Project will remediate the 100 Areas liquid waste site identified in the Interim Action Record of Decision for the 100- BC-1, 100-DR-1, and 100-HR-1 Operable Units. These sites are located in the 100 Area of the Hanford Site in Richland, Washington

IDENTIFICATION AND COMPILATION OF UNSATURATED/VADOSE ZONE MODELS

Science.gov (United States)

Many ground-water contamination problems are derived from sources at or near the soil surface. Consequently, the physical and (bio-)chemical behavior of contaminants in the shallow subsurface is of critical importance to the development of protection and remediation strategies. M...

Thermal soil remediation

International Nuclear Information System (INIS)

Nelson, D.

1999-01-01

The environmental properties and business aspects of thermal soil remediation are described. Thermal soil remediation is considered as being the best option in cleaning contaminated soil for reuse. The thermal desorption process can remove hydrocarbons such as gasoline, kerosene and crude oil, from contaminated soil. Nelson Environmental Remediation (NER) Ltd. uses a mobile thermal desorption unit (TDU) with high temperature capabilities. NER has successfully applied the technology to target heavy end hydrocarbon removal from Alberta's gumbo clay in all seasons. The TDU consist of a feed system, a counter flow rotary drum kiln, a baghouse particulate removal system, and a secondary combustion chamber known as an afterburner. The technology has proven to be cost effective and more efficient than bioremediation and landfarming

Preface: Research advances in vadose zone hydrology through simulations with the TOUGH codes

International Nuclear Information System (INIS)

Finsterle, Stefan; Oldenburg, Curtis M.

2004-01-01

Numerical simulators are playing an increasingly important role in advancing our fundamental understanding of hydrological systems. They are indispensable tools for managing groundwater resources, analyzing proposed and actual remediation activities at contaminated sites, optimizing recovery of oil, gas, and geothermal energy, evaluating subsurface structures and mining activities, designing monitoring systems, assessing the long-term impacts of chemical and nuclear waste disposal, and devising improved irrigation and drainage practices in agricultural areas, among many other applications. The complexity of subsurface hydrology in the vadose zone calls for sophisticated modeling codes capable of handling the strong nonlinearities involved, the interactions of coupled physical, chemical and biological processes, and the multiscale heterogeneities inherent in such systems. The papers in this special section of ''Vadose Zone Journal'' are illustrative of the enormous potential of such numerical simulators as applied to the vadose zone. The papers describe recent developments and applications of one particular set of codes, the TOUGH family of codes, as applied to nonisothermal flow and transport in heterogeneous porous and fractured media (http://www-esd.lbl.gov/TOUGH2). The contributions were selected from presentations given at the TOUGH Symposium 2003, which brought together developers and users of the TOUGH codes at the Lawrence Berkeley National Laboratory (LBNL) in Berkeley, California, for three days of information exchange in May 2003 (http://www-esd.lbl.gov/TOUGHsymposium). The papers presented at the symposium covered a wide range of topics, including geothermal reservoir engineering, fracture flow and vadose zone hydrology, nuclear waste disposal, mining engineering, reactive chemical transport, environmental remediation, and gas transport. This Special Section of ''Vadose Zone Journal'' contains revised and expanded versions of selected papers from the

Application of boreal forest toxicity data in the decision-making process for contaminated soil clean-up remediation at oil and gas fields in Western Canada

International Nuclear Information System (INIS)

Scroggins, R.; Princz, J.; Moody, M.; Olsgard-Dumanski, M.; Haderlein, L.; Moore, B.

2010-01-01

This presentation reported on a multi-year research project in which a broad range of boreal forest test methods for assessing petroleum hydrocarbon (PHC) toxicity in contaminated soil were used to show that clean-up decisions can be made on a field-wide basis through focused biological testing of typical drill sump and flare pit locations within an oil and gas field. Remediation at most sites will likely be limited to the Alberta soil eco-contact guidelines for PHC F2 and F3 fractions. Since Tier 1 eco-contact guidelines are derived using toxicity data from fresh crude and using agricultural plant species, it was more logical to follow a Tier 2 eco-contact pathway approach because most contamination was related to drilling sumps and flare pits containing highly weathered PHCs and species native to the boreal eco-zone of Canada. The site-specific remedial objective (SSRO) option within the Tier 2 guideline was used because of the large number of sites requiring remediation, and the similarity of sites within pre-determined Risk Assessment Zones. For representative contaminated soils, a SSRO was derived from the twenty-fifth percentile of the estimated species sensitivity distribution of all acceptable boreal plant, earthworm, springtail and mite test endpoints. The purpose of the project was to reduce soil volumes sent to landfill during site remediation by showing that residual impacts from weathered PHC in soil do not have damaging effects on boreal forest receptors following remediation. Data was included to show the value of this approach and the variability between sites and their effect on regionalizing a Tier 2 eco-contact guideline.

Application of boreal forest toxicity data in the decision-making process for contaminated soil clean-up remediation at oil and gas fields in Western Canada

Energy Technology Data Exchange (ETDEWEB)

Scroggins, R.; Princz, J. [Environment Canada, Ottawa, ON (Canada); Moody, M. [Saskatchewan Research Council, Regina, SK (Canada); Olsgard-Dumanski, M.; Haderlein, L. [WorleyParsons Canada, Calgary, AB (Canada); Moore, B. [Devon Canada Corp., Calgary, AB (Canada)

2010-07-01

This presentation reported on a multi-year research project in which a broad range of boreal forest test methods for assessing petroleum hydrocarbon (PHC) toxicity in contaminated soil were used to show that clean-up decisions can be made on a field-wide basis through focused biological testing of typical drill sump and flare pit locations within an oil and gas field. Remediation at most sites will likely be limited to the Alberta soil eco-contact guidelines for PHC F2 and F3 fractions. Since Tier 1 eco-contact guidelines are derived using toxicity data from fresh crude and using agricultural plant species, it was more logical to follow a Tier 2 eco-contact pathway approach because most contamination was related to drilling sumps and flare pits containing highly weathered PHCs and species native to the boreal eco-zone of Canada. The site-specific remedial objective (SSRO) option within the Tier 2 guideline was used because of the large number of sites requiring remediation, and the similarity of sites within pre-determined Risk Assessment Zones. For representative contaminated soils, a SSRO was derived from the twenty-fifth percentile of the estimated species sensitivity distribution of all acceptable boreal plant, earthworm, springtail and mite test endpoints. The purpose of the project was to reduce soil volumes sent to landfill during site remediation by showing that residual impacts from weathered PHC in soil do not have damaging effects on boreal forest receptors following remediation. Data was included to show the value of this approach and the variability between sites and their effect on regionalizing a Tier 2 eco-contact guideline.

APPLIED PHYTO-REMEDIATION TECHNIQUES USING HALOPHYTES FOR OIL AND BRINE SPILL SCARS

Energy Technology Data Exchange (ETDEWEB)

M.L. Korphage; Bruce G. Langhus; Scott Campbell

2003-03-01

Produced salt water from historical oil and gas production was often managed with inadequate care and unfortunate consequences. In Kansas, the production practices in the 1930's and 1940's--before statewide anti-pollution laws--were such that fluids were often produced to surface impoundments where the oil would segregate from the salt water. The oil was pumped off the pits and the salt water was able to infiltrate into the subsurface soil zones and underlying bedrock. Over the years, oil producing practices were changed so that segregation of fluids was accomplished in steel tanks and salt water was isolated from the natural environment. But before that could happen, significant areas of the state were scarred by salt water. These areas are now in need of economical remediation. Remediation of salt scarred land can be facilitated with soil amendments, land management, and selection of appropriate salt tolerant plants. Current research on the salt scars around the old Leon Waterflood, in Butler County, Kansas show the relative efficiency of remediation options. Based upon these research findings, it is possible to recommend cost efficient remediation techniques for slight, medium, and heavy salt water damaged soil. Slight salt damage includes soils with Electrical Conductivity (EC) values of 4.0 mS/cm or less. Operators can treat these soils with sufficient amounts of gypsum, install irrigation systems, and till the soil. Appropriate plants can be introduced via transplants or seeded. Medium salt damage includes soils with EC values between 4.0 and 16 mS/cm. Operators will add amendments of gypsum, till the soil, and arrange for irrigation. Some particularly salt tolerant plants can be added but most planting ought to be reserved until the second season of remediation. Severe salt damage includes soil with EC values in excess of 16 mS/cm. Operators will add at least part of the gypsum required, till the soil, and arrange for irrigation. The following

Environmental remediation activities at the Ningyo-toge Uranium Mine, Japan

International Nuclear Information System (INIS)

Saito, Hiroshi; Taki, Tomohiro

2011-01-01

Ningyo-toge Uranium Mine is subject to the environmental remediation. The main purposes are to take measures to ensure the radiation protection from the exposure pathways to humans in future, and to prevent the occurrence of mining pollution. The Mill Tailings Pond in the Ningyo-toge Uranium Mine has deposited mining waste and impounded water as a buffer reservoir before it is transferred to the Water Treatment Facility. It is located at the upstream of the water-source river, and therefore, for the environmental remediation, the highest priority has been put to it among many facilities in the Mine. So far, basic concept has been examined and planning has been carried out for the remediation. Also, a great number of data has been acquired, and using the data, some remediation activities have already begun, including designing for the upstream part of the Mill Tailings Pond. According to the current plan, the Mill Tailings Pond will be covered by capping following dewatering and compressing of mill tailings. The capping is composed of 'radon barrier' for lowering radon-gas dissipation and dose rate, and its protection layer. Natural materials are planned to be used for the capping to alleviate the future maintenance. After capping, data will be accumulated to verify the effectiveness of the capping, and if proved effective, it will be utilized for the capping of the downstream part. (author)

VALUING ACID MINE DRAINAGE REMEDIATION IN WEST VIRGINIA: A HEDONIC MODELING APPROACH

Science.gov (United States)

States with active and abandoned mines face large private and public costs to remediate damage to streams and rivers from acid mine drainage (AMD). Appalachian states have an especially large number of contaminated streams and rivers, and the USGS places AMD as the primary source...

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

Using artificial sweeteners to identify contamination sources and infiltration zones in a coupled river-aquifer system

Science.gov (United States)

Bichler, Andrea; Muellegger, Christian; Hofmann, Thilo

2014-05-01

In shallow or unconfined aquifers the infiltration of contaminated river water might be a major threat to groundwater quality. Thus, the identification of possible contamination sources in coupled surface- and groundwater systems is of paramount importance to ensure water quality. Micropollutants like artificial sweeteners are promising markers for domestic waste water in natural water bodies. Compounds, such as artificial sweeteners, might enter the aquatic environment via discharge of waste water treatment plants, leaky sewer systems or septic tanks and are ubiquitously found in waste water receiving waters. The hereby presented field study aims at the (1) identification of contamination sources and (2) delineation of infiltration zones in a connected river-aquifer system. River bank filtrate in the groundwater body was assessed qualitatively and quantitatively using a combined approach of hydrochemical analysis and artificial sweeteners (acesulfame ACE) as waste water markers. The investigated aquifer lies within a mesoscale alpine head water catchment and is used for drinking water production. It is hypothesized that a large proportion of the groundwater flux originates from bank filtrate of a nearby losing stream. Water sampling campaigns in March and July 2012 confirmed the occurrence of artificial sweeteners at the investigated site. The municipal waste water treatment plant was identified as point-source for ACE in the river network. In the aquifer ACE was present in more than 80% of the monitoring wells. In addition, water samples were classified according to their hydrochemical composition, identifying two predominant types of water in the aquifer: (1) groundwater influenced by bank filtrate and (2) groundwater originating from local recharge. In combination with ACE concentrations a third type of water could be discriminated: (3) groundwater influence by bank filtrate but infiltrated prior to the waste water treatment plant. Moreover, the presence of ACE

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.

Remedy for Radiation Fear — Discard the Politicized Science

International Nuclear Information System (INIS)

Cuttler, J.

2014-01-01

While seeking a remedy for the crisis of radiation fear in Japan, the author reread a recent article on radiation hormesis. It describes the motivation for creating this fear and mentions the evidence, in the first UNSCEAR report, of a factor of 3 reduction in leukemia incidence of the Hiroshima atom-bomb survivors in the low dose zone. Drawing a graph of the data reveals a hormetic J-curve, not a straight line as reported. UNSCEAR data on the lifespan reduction of mice and Guinea pigs exposed continuously to radium gamma rays indicate a threshold at about 2 gray per year. This contradicts the conceptual basis for radiation protection and risk determination that was established in 1956-58. In this paper, beneficial effects and thresholds for harmful effects are discussed, and the biological mechanism is explained. The key point: the rate of spontaneous DNA damage (double-strand breaks) is more than 1000 times the rate caused by background radiation. It is the effect of radiation on an organism's very powerful adaptive protection systems that determines the dose-response characteristic. Low radiation up-regulates the adaptive protection systems, while high radiation impairs these systems. The remedy for radiation fear is to expose and discard the politicized science

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

Cost considerations in remediation and disposal

International Nuclear Information System (INIS)

Dance, J.T.; Huddleston, R.D.

1999-01-01

Opportunities for assessing the costs associated with the reclamation and remediation of sites contaminated by oilfield wastes are discussed. The savings can be maximized by paying close attention to five different aspects of the overall site remediation and disposal process. These are: (1) highly focused site assessment, (2) cost control of treatment and disposal options, (3) value added cost benefits, (4) opportunities to control outside influences during the remedial process, and (5) opportunities for managing long-term liabilities and residual risk remaining after the remedial program is completed. It is claimed that addressing these aspects of the process will ultimately lower the overall cost of site remediation and waste disposal

Draft Hanford Remedial Action Environmental Impact Statement and Comprehensive Land Use Plan: Volume 2 of 4

International Nuclear Information System (INIS)

1996-08-01

This appendix discusses the scope of actions addressed in the Draft Hanford Remedial Action Environmental Impact Statement and Comprehensive Land Use Plan. To address the purpose and need for agency action identified in Chapter 2.0 of the HRA-EIS, the scope includes an evaluation of the potential environmental impacts associated with the remedial actions to be conducted by the US Department of Energy (DOE) under the provisions of the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) (Ecology et al. 1989). These remedial actions would bring the Hanford Site into compliance with the applicable requirements of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) and the Resource Conservation and Recovery Act of 1976 (RCRA). The DOE program responsible for conducting remedial actions at the Hanford Site is referred to as the Richland Environmental Restoration (ER) Project. The Richland ER Project encompasses the following projects: radiation area remedial actions and underground storage tanks (UST); RCRA closures; single-shell tank (SST) closures; past-practice waste site operable unit (source and groundwater) remedial actions; surplus facility decommissioning; and waste storage and disposal facilities

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.

[Cognitive remediation and nursing care].

Science.gov (United States)

Schenin-King, Palmyre; Thomas, Fanny; Braha-Zeitoun, Sonia; Bouaziz, Noomane; Januel, Dominique

2016-01-01

Therapies based on cognitive remediation integrate psychiatric care. Cognitive remediation helps to ease cognitive disorders and enable patients to improve their day-to-day lives. It is essential to complete nurses' training in this field. This article presents the example of a patient with schizophrenia who followed the Cognitive Remediation Therapy programme, enabling him to access mainstream employment. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Remedy for radiation fear - discard the politicized science

Energy Technology Data Exchange (ETDEWEB)

Cuttler, J.M. [Cuttler and Associates Inc., Mississauga, Ontario (Canada)

2013-12-15

While seeking a remedy for the ongoing crisis of radiation fear in Japan and everywhere else, the author reread a recent article on radiation hormesis. It describes the political motivation for creating this fear and mentions the evidence, in the first UNSCEAR report, of a factor of 3 reduction in leukemia incidence of the Hiroshima a-bomb survivors in the low dose zone. Producing a graph of the tabulated data reveals that they fit a hormetic J-curve, not a straight line as reported. UNSCEAR data on the lifespan reduction of mice and Guinea pigs exposed continuously to radium gamma rays indicate a threshold at about 2 gray per year. This information contradicts the conceptual basis for radiation protection and risk determination that was established in 1956-58. In this paper, beneficial effects and thresholds for harmful effects are discussed, and the biological mechanism is explained. The key point is the discovery that the rate of spontaneous DNA damage (double-strand breaks) is more than 1000 times the rate caused by average background radiation. It is the effect of radiation on an organism's very powerful adaptive protection systems that determines the dose-response characteristic. Low radiation up-regulates adaptive protection systems, while high radiation impairs these systems. The remedy for radiation fear is to expose and discard the politicized science. (author)

White Oak Creek Watershed: Melton Valley Area Remedial Investigation Report, Oak Ridge National Laboratory, Oak Ridge, Tennessee: Volume 1 Main Text

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-11-01

The purpose of this Remedial Investigation (RI) report is to present an analysis of the Melton Valley portion of the White Oak Creek (WOC) watershed, which will enable the US Department of Energy (DOE) to pursue a series of cost-effective remedial actions resulting in site cleanup and stabilization. In this RI existing levels of contamination and radiological exposure are compared to levels acceptable for future industrial and potential recreational use levels at the site. This comparison provides a perspective for the magnitude of remedial actions required to achieve a site condition compatible with relaxed access restrictions over existing conditions. Ecological risk will be assessed to evaluate measures required for ecological receptor protection. For each subbasin, this report will provide site-specific analyses of the physical setting including identification of contaminant source areas, description of contaminant transport pathways, identification of release mechanisms, analysis of contaminant source interactions with groundwater, identification of secondary contaminated media associated with the source and seepage pathways, assessment of potential human health and ecological risks from exposure to contaminants, ranking of each source area within the subwatershed, and outline the conditions that remedial technologies must address to stop present and future contaminant releases, prevent the spread of contamination and achieve the goal of limiting environmental contamination to be consistent with a potential recreational use of the site.

White Oak Creek Watershed: Melton Valley Area Remedial Investigation Report, Oak Ridge National Laboratory, Oak Ridge, Tennessee: Volume 1 Main Text

International Nuclear Information System (INIS)

1996-11-01

The purpose of this Remedial Investigation (RI) report is to present an analysis of the Melton Valley portion of the White Oak Creek (WOC) watershed, which will enable the US Department of Energy (DOE) to pursue a series of cost-effective remedial actions resulting in site cleanup and stabilization. In this RI existing levels of contamination and radiological exposure are compared to levels acceptable for future industrial and potential recreational use levels at the site. This comparison provides a perspective for the magnitude of remedial actions required to achieve a site condition compatible with relaxed access restrictions over existing conditions. Ecological risk will be assessed to evaluate measures required for ecological receptor protection. For each subbasin, this report will provide site-specific analyses of the physical setting including identification of contaminant source areas, description of contaminant transport pathways, identification of release mechanisms, analysis of contaminant source interactions with groundwater, identification of secondary contaminated media associated with the source and seepage pathways, assessment of potential human health and ecological risks from exposure to contaminants, ranking of each source area within the subwatershed, and outline the conditions that remedial technologies must address to stop present and future contaminant releases, prevent the spread of contamination and achieve the goal of limiting environmental contamination to be consistent with a potential recreational use of the site

Electrokinetic remediation of plutonium-contaminated nuclear site wastes: Results from a pilot-scale on-site trial

International Nuclear Information System (INIS)

Agnew, Kieran; Cundy, Andrew B.; Hopkinson, Laurence; Croudace, Ian W.; Warwick, Phillip E.; Purdie, Philip

2011-01-01

This paper examines the field-scale application of a novel low-energy electrokinetic technique for the remediation of plutonium-contaminated nuclear site soils, using soil wastes from the Atomic Weapons Establishment (AWE) Aldermaston site, Berkshire, UK as a test medium. Soils and sediments with varying composition, contaminated with Pu through historical site operations, were electrokinetically treated at laboratory-scale with and without various soil pre-conditioning agents. Results from these bench-scale trials were used to inform a larger on-site remediation trial, using an adapted containment pack with battery power supply. 2.4 m 3 (ca. 4 tonnes) of Pu-contaminated soil was treated for 60 days at a power consumption of 33 kW h/m 3 , and then destructively sampled. Radiochemical data indicate mobilisation of Pu in the treated soil, and migration (probably as a negatively charged Pu-citrate complex) towards the anodic compartment of the treatment cell. Soil in the cathodic zone of the treatment unit was remediated to a level below free-release disposal thresholds (1.7 Bq/g, or <0.4 Bq/g above background activities). The data show the potential of this method as a low-cost, on-site tool for remediation of radioactively contaminated soils and wastes which can be operated remotely on working sites, with minimal disruption to site infrastructure or operations.

Radon remedial actions in schools of Friuli Venezia Giulia region (NE Italy)

International Nuclear Information System (INIS)

Giovani, C.; Cappelletto, C.; Garavaglia, M.; Pividore, S.; Villalta, R.

2004-01-01

In the last four years the Regional Agency of Environmental Protection (ARPA) of Friuli Venezia Giulia carried out a survey to determine the radon concentration in the schools of the area. During the survey all the 1320 schools and kindergartens of the region were investigated with more than 5000 measurements. In about 2% of cases, radon concentrations exceeded the reference levels of Italian law and remedial actions were performed. In collaboration with the Building Engineering Department of Udine University, ARPA FVG edited a manual concerning indications and proposals for building protection against radon. The environmental physics section of ARPA FVG, was heavily involved in the remedial action, both in the design of the action and in the investigation of effectiveness. In more than 20 schools the owners following ARPA indications solved the problem of high radon concentrations. In this paper the authors report the main type of applied remedial actions grouped taking into account the different remedial methodology. In Friuli Venezia Giulia region the main radon source is represented by soil. The contribution of building materials to high radon concentrations is negligible. The most common remedial actions consisted in natural or artificial depressurization of the soil or the crawlspace with respect to indoor building. Sometimes air was pumped into the building or air exchange number was increased. The authors show in detail the design of the performed investigations: these involved different measurement sets with passive electrets and active instruments for continuous data collection. Measurements usually last 3 contiguous weeks and are followed by long period measurements with solid track detectors. Optimization of remedial action performance was investigated when remedial action consisted in active air extraction from the soil under the buildings and fan time regulation was possible. Very often simple and cheap actions allowed a reduction of 90% in radon

Application of natural resource valuation concepts for development of sustainable remediation plans for groundwater.

Science.gov (United States)

Connor, John A; Paquette, Shawn; McHugh, Thomas; Gie, Elaine; Hemingway, Mark; Bianchi, Gino

2017-12-15

This paper explores the application of natural resource assessment and valuation procedures as a tool for developing groundwater remediation strategies that achieve the objectives for health and environmental protection, in balance with considerations of economic viability and conservation of natural resources. The natural resource assessment process, as applied under U.S. and international guidelines, entails characterization of groundwater contamination in terms of the pre-existing beneficial services of the impacted resource, the loss of these services caused by the contamination, and the measures and associated costs necessary to restore or replace the lost services. Under many regulatory programs, groundwater remediation objectives assume that the impacted groundwater may be used as a primary source of drinking water in the future, even if not presently in use. In combination with a regulatory preference for removal or treatment technologies, this assumed exposure, while protective of human health, can drive the remedy selection process toward remedies that may not be protective of the groundwater resource itself or of the other natural resources (energy, materials, chemicals, etc.) that may be consumed in the remediation effort. To achieve the same health and environmental protection goals under a sustainable remediation framework, natural resource assessment methods can be applied to restore the lost services and preserve the intact services of the groundwater so as to protect both current and future users of that resource. In this paper, we provide practical guidelines for use of natural resource assessment procedures in the remedy selection process and present a case study demonstrating the use of these protocols for development of sustainable remediation strategies. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Traditional medicinal plants in Nigeria--remedies or risks.

Science.gov (United States)

Awodele, O; Popoola, T D; Amadi, K C; Coker, H A B; Akintonwa, A

2013-11-25

Soil pollution due to increasing industrialization is a reality that is taking its toll on mankind today. Considering the population of people that use herbal remedies especially in developing countries and the discharge of industrial waste on surrounding herbal vegetation, it is imperative to determine the heavy metals contamination in some commonly used medicinal plants. Representative samples of five medicinal plants Ageratum conyzoides, Aspilia africana, Alchornea cordifolia, Amaranthus brasiliensis and Chromolaena odorata were collected from Ikpoba-Okha L.G.A, Edo State Nigeria, around a paint company and another set of same plants were collected from a non-polluted source. Dried leaves and roots of collected plants were digested and analyzed using Atomic Absorption Spectrophotometer (AAS) for the presence of Lead (Pb), Cadmium (Cd), Chromium (Cr), Nickel (Ni) and Zinc (Zn). Soil samples from polluted and non-polluted areas were also analyzed to ascertain the levels of these heavy metals in the environment. Results show that the concentrations of these heavy metals in the leaves and roots of plants collected from polluted soil were significantly higher than those obtained from unpolluted soil. Correspondingly heavy metal concentrations were significantly higher in polluted than in unpolluted soil samples. As part of continuing effort in the standardization of traditional remedies, environmental contamination control and abatement is evident. The source of medicinal plants/herbs should also be a cause for concern since the toxicity of medicinal plants is sometimes associated with environmental sources of the plants. © 2013 Elsevier Ireland Ltd. All rights reserved.

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

Remediation of spatial processing disorder (SPD).

Science.gov (United States)

Graydon, Kelley; Van Dun, Bram; Tomlin, Dani; Dowell, Richard; Rance, Gary

2018-05-01

To determine the efficacy of deficit-specific remediation for spatial processing disorder, quantify effects of remediation on functional listening, and determine if remediation is maintained. Participants had SPD, diagnosed using the Listening in Spatialised Noise-Sentences test. The LiSN and Learn software was provided as auditory training. Post-training, repeat LiSN-S testing was conducted. Questionnaires pre- and post-training acted as subjective measures of remediation. A late-outcome assessment established long-term effects of remediation. Sixteen children aged between 6;3 [years; months] and 10;0 completed between 20 and 146 training games. Post-training LiSN-S improved in measures containing spatial cues (p ≤ 0.001) by 2.0 SDs (3.6 dB) for DV90, 1.8 SDs for SV90 (3.2 dB), 1.4 SDs for spatial advantage (2.9 dB) and 1.6 SDs for total advantage (3.3 dB). Improvement was also found in the DV0 condition (1.4 dB or 0.5 SDs). Post-training changes were not significant in the talker advantage measure (1.0 dB or 0.4 SDs) or the SV0 condition (0.3 dB or 0.1 SDs). The late-outcome assessment demonstrated improvement was maintained. Subjective improvement post-remediation was observed using the parent questionnaire. Children with SPD had improved ability to utilise spatial cues following deficit-specific remediation, with the parent questionnaire sensitive to remediation. Effects of the remediation also appear to be sustained.

Stream remediation following a gasoline spill

International Nuclear Information System (INIS)

Owens, E.H.; Reiter, G.A.; Challenger, G.

2000-01-01

On June 10, 1999, a pipe ruptured on the Olympic Pipe Line causing the release, explosion and fire of up to one million litres of gasoline in Bellingham, Washington. It affected approximately 5 km of the Whatcom Creek ecosystem. Following the incident, several concurrent activities in the source area and downstream occurred. This paper discussed the remediation of the affected stream bed sections. During the period July 6 - August 16, an interagency project was implemented. It involved mechanical, manual, and hydraulic in-situ treatment techniques to remove the gasoline from the stream bed and the banks. In addition, a series of controlled, hydraulic flushes were conducted. The sluice or control gates at the head of the Whatcom Creek were opened each night, and bigger flushes took place before and after the treatments. Simultaneously, water and sediment were sampled and analysed. The data obtained provided information on the state of the initial stream water and stream sediment and on the effects that the remediation had had. The residual gasoline was successfully removed from the sediments and river banks in six weeks. No downstream movement of the released gasoline towards Bellingham was detected. 3 refs., 2 tabs., 11 figs

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...

A model for the development of marginal water sources in arid zones: The case of the Negev Desert, Israel

Science.gov (United States)

Brimberg, Jack; Oron, Gideon; Mehrez, Abraham

1993-09-01

A management model is presented for the optimal development of marginal water sources in arid zones in conjunction with minimizing the dependence on high-quality water. These marginal sources, which may include among others saline groundwater, treated wastewater, and runoff water, are required to augment a limited supply from regional sources. The objective is to minimize operational and capital costs while simultaneously allocating a conventional regional supply in a best way among a set of local sites. A novel aspect is the consideration of water quality as an additional constraint in the decision model. In this way an optimal investment strategy for marginal water source development and use is obtained while satisfying quality requirements at the individual sites. The model formulated takes the form of a mixed binary integer linear problem. The main purpose of the presented model is to delineate a methodology for marginal water considerations and development in arid zones. Water qualities, supply and demand for diverse uses, and related costs are of primary importance. Several simplifying assumptions are made, such as aggregation on an annual basis, in order to cope with the essential features of the problem at a reasonable level of complexity. These assumptions may be relaxed at a later, more detailed stage of analysis. A case study of the Negev Desert in southern Israel is shown. An important conclusion is that saline groundwater production at local demand sites should be increased dramatically. The usefulness of sensitivity analysis in the decision process is also demonstrated.

About necessity of remediation and re-cultivation of Taboshar districts' tailings

International Nuclear Information System (INIS)

Salomov, J.A.; Mirsaidov, I.U.; Barotov, A.M.

2012-01-01

city by local population in general with high radionuclide contamination content on the surface of uranium tailings, in zones of dumps location and former uranium open pits where local population has a free access for cattle pasture and other needs can lead to increase of limit dose for public which is 1 mSv/year. That's why, an approach is necessary for finding sustainable solution of Taboshar district's tailings remediation and its water resources which involves tailings remediation taking into account social and medical aspects of public life who are living in these territories.

Field Sampling and Analysis Plan for the Remedial Investigation of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1992-10-01

This report provides responses to US Environmental Protection Agency Region IV EPA-M and Tennessee Department of Environment and Conservation Oversite Division (TDEC-O) comments on report ORNL/ER-58, Field Sampling and Analysis Plan for the Remedial Investigation of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Waste Area Grouping (WAG) 2 consists of the White Oak Creek (WOC) drainage system downgradient of the major ORNL WAGs in the WOC watershed. A strategy for the remedial investigation (RI) of WAG2 was developed in report ES/ER-14 ampersand Dl, Remedial Investigation Plan for Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. This strategy takes full advantage of WAG2's role as an integrator of contaminant releases from the ORNL WAGs in the WOC watershed, and takes full advantage of WAG2's role as a conduit for contaminants from the ORNL site to the Clinch River. The strategy calls for a multimedia environmental monitoring and characterization program to be conducted in WAG2 while upgradient contaminant sources are being remediated. This monitoring and characterization program will (1) identify and quantify contaminant fluxes, (2) identify pathways of greatest concern for human health and environmental risk, (3) improve conceptual models of contaminant movement, (4) support the evaluation of remedial alternatives, (5) support efforts to prioritize sites for remediation, (6) document the reduction in contaminant fluxes following remediation, and (7) support the eventual remediation of WAG2. Following this strategy, WAG2 has been termed an ''integrator WAG,'' and efforts in WAG2 over the short term are directed toward supporting efforts to remediate the contaminant ''source WAGS'' at ORNL

Water Supply Source Evaluation in Unmanaged Aquifer Recharge Zones: The Mezquital Valley (Mexico Case Study

Directory of Open Access Journals (Sweden)

Antonio Hernández-Espriú

2016-12-01

Full Text Available The Mezquital Valley (MV hosts the largest unmanaged aquifer recharge scheme in the world. The metropolitan area of Mexico City discharges ~60 m3/s of raw wastewater into the valley, a substantial share of which infiltrates into the regional aquifer. In this work, we aim to develop a comprehensive approach, adapted from oil and gas reservoir modeling frameworks, to assess water supply sources located downgradient from unmanaged aquifer recharge zones. The methodology is demonstrated through its application to the Mezquital Valley region. Geological, geoelectrical, petrophysical and hydraulic information is combined into a 3D subsurface model and used to evaluate downgradient supply sources. Although hydrogeochemical variables are yet to be assessed, outcomes suggest that the newly-found groundwater sources may provide a long-term solution for water supply. Piezometric analyses based on 25-year records suggest that the MV is close to steady-state conditions. Thus, unmanaged recharge seems to have been regulating the groundwater balance for the last decades. The transition from unmanaged to managed recharge is expected to provide benefits to the MV inhabitants. It will also be likely to generate new uncertainties in relation to aquifer dynamics and downgradient systems.

32 CFR 310.47 - Civil remedies.

Science.gov (United States)

2010-07-01

... 32 National Defense 2 2010-07-01 2010-07-01 false Civil remedies. 310.47 Section 310.47 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) PRIVACY PROGRAM DOD PRIVACY PROGRAM Privacy Act Violations § 310.47 Civil remedies. In addition to specific remedial...

LCA of Soil and Groundwater Remediation

DEFF Research Database (Denmark)

Søndergaard, Gitte Lemming; Owsianiak, Mikolaj

2018-01-01

Today, there is increasing interest in applying LCA to support decision-makers in contaminated site management. In this chapter, we introduce remediation technologies and associated environmental impacts, present an overview of literature findings on LCA applied to remediation technologies...... and present methodological issues to consider when conducting LCAs within the area. Within the field of contaminated site remediation , a terminology distinguishing three types of environmental impacts: primary, secondary and tertiary, is often applied. Primary impacts are the site-related impacts due...... and efficiency of remediation, which are important for assessment or primary impacts; (ii) robust assessment of primary impacts using site-specific fate and exposure models; (iii) weighting of primary and secondary (or tertiary) impacts to evaluate trade-offs between life cycle impacts from remediation...

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

Vadose zone studies at an industrial contaminated site: the vadose zone monitoring system and cross-hole geophysics

Science.gov (United States)

Fernandez de Vera, Natalia; Beaujean, Jean; Jamin, Pierre; Nguyen, Frédéric; Dahan, Ofer; Vanclooster, Marnik; Brouyère, Serge

2014-05-01

In order to improve risk characterization and remediation measures for soil and groundwater contamination, there is a need to improve in situ vadose zone characterization. However, most available technologies have been developed in the context of agricultural soils. Such methodologies are not applicable at industrial sites, where soils and contamination differ in origin and composition. In addition, most technologies are applicable only in the first meters of soils, leaving deeper vadose zones with lack of information, in particular on field scale heterogeneity. In order to overcome such difficulties, a vadose zone experiment has been setup at a former industrial site in Belgium. Industrial activities carried out on site left a legacy of soil and groundwater contamination in BTEX, PAH, cyanide and heavy metals. The experiment comprises the combination of two techniques: the Vadose Zone Monitoring System (VMS) and cross-hole geophysics. The VMS allows continuous measurements of water content and temperature at different depths of the vadose zone. In addition, it provides the possibility of pore water sampling at different depths. The system is formed by a flexible sleeve containing monitoring units along its depth which is installed in a slanted borehole. The flexible sleeve contains three types of monitoring units in the vadose zone: Time Domain Transmissometry (TDT), which allows water content measurements; Vadose Sampling Ports (VSP), used for collecting water samples coming from the matrix; the Fracture Samplers (FS), which are used for retrieving water samples from the fractures. Cross-hole geophysics techniques consist in the injection of an electrical current using electrodes installed in vertical boreholes. From measured potential differences, detailed spatial patterns about electrical properties of the subsurface can be inferred. Such spatial patterns are related with subsurface heterogeneities, water content and solute concentrations. Two VMS were

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

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.

Lessons Learned from Environmental Remediation Programmes

Energy Technology Data Exchange (ETDEWEB)

NONE

2014-03-15

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

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

Sources, Speciation and Mobility of Plutonium and Other Transuranics in the Groundwater at the Savannah River Site (Sept. 2003-Sept. 2006)

International Nuclear Information System (INIS)

Buesseler, K.O.; Kaplan, D.; Peterson, S.; Dai, M.

2006-01-01

The intent of this research effort is to: (1) provide the basis for accurate modeling and prediction of actinide transport; (2) allow for remediation strategies to be planned that might use in-situ manipulations of geochemical variables to enhance (for extraction) or retard (for immobilization) Pu mobility in the groundwater zone; (3) identify specific Pu sources and the extent of far field, or long-term migration of transuranics in groundwater; (4) reduce costly uncertainty in performance and risk assessment calculations. This new knowledge is essential to ensure continued public and worker safety at the DOE sites and the efficient management of cleanup and containment strategies

Effect of Remediation Parameters on in-Air Ambient Dose Equivalent Rates When Remediating Open Sites with Radiocesium-contaminated Soil.

Science.gov (United States)

Malins, Alex; Kurikami, Hiroshi; Kitamura, Akihiro; Machida, Masahiko

2016-10-01

Calculations are reported for ambient dose equivalent rates [H˙*(10)] at 1 m height above the ground surface before and after remediating radiocesium-contaminated soil at wide and open sites. The results establish how the change in H˙*(10) upon remediation depends on the initial depth distribution of radiocesium within the ground, on the size of the remediated area, and on the mass per unit area of remediated soil. The remediation strategies considered were topsoil removal (with and without recovering with a clean soil layer), interchanging a topsoil layer with a subsoil layer, and in situ mixing of the topsoil. The results show the ratio of the radiocesium components of H˙*(10) post-remediation relative to their initial values (residual dose factors). It is possible to use the residual dose factors to gauge absolute changes in H˙*(10) upon remediation. The dependency of the residual dose factors on the number of years elapsed after fallout deposition is analyzed when remediation parameters remain fixed and radiocesium undergoes typical downward migration within the soil column.

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 ...

Characterization and Potential Remediation Approaches for Vadose Zone Contamination at Hanford 241-SX Tank Farm-13235

International Nuclear Information System (INIS)

Eberlein, Susan J.; Sydnor, Harold A.; Parker, Danny L.; Glaser, Danney R.

2013-01-01

Unplanned releases of radioactive and hazardous wastes have occurred at the 241-SX Tank Farm on the U.S. Department of Energy Hanford Site in southeast Washington State. Interim and long-term mitigation efforts are currently under evaluation for 241-SX Tank Farm. Two contiguous interim surface barriers have been designed for deployment at 241-SX Tank Farm to reduce future moisture infiltration; however, construction of the surface barriers has been deferred to allow testing of alternative technologies for soil moisture reduction and possibly contaminant source term reduction. Previous tests performed by other organizations at the Hanford Site have demonstrated that: vadose zone desiccation using large diameter (greater than 4 inch) boreholes is feasible; under certain circumstances, mobile contaminants may be removed in addition to water vapor; and small diameter (approximately 2 inch) boreholes (such as those placed by the direct push hydraulic hammer) can be used to perform vapor extractions. Evaluation of the previous work combined with laboratory test results have led to the design of a field proof-of-principle test to remove water and possibly mobile contaminants at greater depths, using small boreholes placed with the direct push unit

Characterization and Potential Remediation Approaches for Vadose Zone Contamination at Hanford 241-SX Tank Farm - 13235

Energy Technology Data Exchange (ETDEWEB)

Eberlein, Susan J.; Sydnor, Harold A.; Parker, Danny L.; Glaser, Danney R. [Washington River Protection Solutions, P.O. Box 850, Richland, WA, 99352 (United States)

2013-07-01

Unplanned releases of radioactive and hazardous wastes have occurred at the 241-SX Tank Farm on the U.S. Department of Energy Hanford Site in southeast Washington State. Interim and long-term mitigation efforts are currently under evaluation for 241-SX Tank Farm. Two contiguous interim surface barriers have been designed for deployment at 241-SX Tank Farm to reduce future moisture infiltration; however, construction of the surface barriers has been deferred to allow testing of alternative technologies for soil moisture reduction and possibly contaminant source term reduction. Previous tests performed by other organizations at the Hanford Site have demonstrated that: vadose zone desiccation using large diameter (greater than 4 inch) boreholes is feasible; under certain circumstances, mobile contaminants may be removed in addition to water vapor; and small diameter (approximately 2 inch) boreholes (such as those placed by the direct push hydraulic hammer) can be used to perform vapor extractions. Evaluation of the previous work combined with laboratory test results have led to the design of a field proof-of-principle test to remove water and possibly mobile contaminants at greater depths, using small boreholes placed with the direct push unit. (authors)

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…

Remediation: Higher Education's Bridge to Nowhere

Science.gov (United States)

Complete College America, 2012

2012-01-01

The intentions were noble. It was hoped that remediation programs would be an academic bridge from poor high school preparation to college readiness. Sadly, remediation has become instead higher education's "Bridge to Nowhere." This broken remedial bridge is travelled by some 1.7 million beginning students each year, most of whom will…

Subsurface Interim Measures/Interim Remedial Action Plan and Decision Document for the 903 Pad, Mound, and East Trenches Areas (Operable Unit No. 2)

International Nuclear Information System (INIS)

1992-01-01

The Department of Energy (DOE) is pursuing an Interim Measure/Interim Remedial Action (IM/IRA) at the 903 Pad, Mound, and East Trenches Areas (Operable Unit No. 2) at the Rocky Flats Plant (RFP). This MIRA is to be conducted to provide information that will aid in the selection and design of final remedial actions at OU2 that will address removal of suspected free-phase volatile organic compound (VOC) contamination. The Plan involves investigating the removal of residual free-phase VOCs by in situ vacuum-enhanced vapor extraction technology at 3 suspected VOC source areas within OU2. VOC-contaminated vapors extracted from the subsurface would be treated by granular activated carbon (GAC) adsorption and discharged. The Plan also includes water table depression, when applicable at the test sites, to investigate the performance of vapor extraction technology in the saturated zone. The Plan provides for treatment of any contaminated ground water recovered during the IM/IRA at existing RFP treatment facilities. The proposed MVIRA Plan is presented in the document entitled ''Proposed Subsurface Interim Measures/Interim Remedial Action Plan/Environmental Assessment and Decision Document, 903 Pad, Mound, and East Trenches Areas, Operable Unit No. 2, '' dated 20 March 1992. Information concerning the proposed Subsurface IM/IRA was presented during a DOE Quarterly Review meeting held on 07 April 1992 and a public meeting held on 07 May 1992, at the Marriott Hotel in Golden, Colorado. The Responsiveness Summary presents DOE's response to all comments received at the public meeting, as well as those mailed to date to DOE during the public comment period

Strategic Evaluation Tool for Surface Water Quality Management Remedies in Drinking Water Catchments

Directory of Open Access Journals (Sweden)

Huda Almaaofi

2017-09-01

Full Text Available Drinking water catchments (DWC are under pressure from point and nonpoint source pollution due to the growing human activities. This worldwide challenge is causing number of adverse effects, such as degradation in water quality, ecosystem health, and other economic and social pressures. Different evaluation tools have been developed to achieve sustainable and healthy drinking water catchments. However, a holistic and strategic framework is still required to adequately consider the uncertainty associated with feasible management remedies of surface water quality in drinking water catchments. A strategic framework was developed to adequately consider the uncertainty associated with management remedies for surface water quality in drinking water catchments. A Fuzzy Multiple Criteria Decision Analysis (FMCDA approach was embedded into a strategic decision support framework to evaluate and rank water quality remediation options within a typical fixed budget constraint faced by bulk water providers. The evaluation framework consists of four core aspects; namely, water quality, environmental, economic and social, and number of associated quantitative and qualitative criteria and sub-criteria. Final remediation strategy ranking was achieved through the application of the Euclidean Distance by the In-center of Centroids (EDIC.

Proceedings of the remediation technologies symposium 2007

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-07-01

This conference provided a forum to discuss the remediation of contaminated sites. It was attended by all industry sectors that have an interest in learning about technical issues in environmental remediation research and the latest innovations in soil and groundwater remediation and industrial pollutant treatments. Cost effective in-situ and ex-situ soil reclamation strategies were presented along with groundwater and surface water remediation strategies. The diversified sessions at this conference were entitled: regulatory update; Montreal Centre of Excellence in Brownfields Rehabilitation; soil and groundwater remediation through the Program of Energy Research and Development at Environment Canada; technology from the Netherlands; bioremediation; hydrocarbons; in-situ remediation; phytoremediation; salt management; unique locations; and, miscellaneous issues. Some areas and case studies covered in the presentations included: biological and non-biological treatments; thermal desorption; encapsulation; natural attenuation; multi-phase extraction; electrochemical remediation; and membrane technology. The conference featured 63 presentations, of which 23 have been catalogued separately for inclusion in this database. tabs., figs.

Proceedings of the remediation technologies symposium 2007

International Nuclear Information System (INIS)

2007-01-01

This conference provided a forum to discuss the remediation of contaminated sites. It was attended by all industry sectors that have an interest in learning about technical issues in environmental remediation research and the latest innovations in soil and groundwater remediation and industrial pollutant treatments. Cost effective in-situ and ex-situ soil reclamation strategies were presented along with groundwater and surface water remediation strategies. The diversified sessions at this conference were entitled: regulatory update; Montreal Centre of Excellence in Brownfields Rehabilitation; soil and groundwater remediation through the Program of Energy Research and Development at Environment Canada; technology from the Netherlands; bioremediation; hydrocarbons; in-situ remediation; phytoremediation; salt management; unique locations; and, miscellaneous issues. Some areas and case studies covered in the presentations included: biological and non-biological treatments; thermal desorption; encapsulation; natural attenuation; multi-phase extraction; electrochemical remediation; and membrane technology. The conference featured 63 presentations, of which 23 have been catalogued separately for inclusion in this database. tabs., figs

Geochemical Characterization of Chromate Contamination in the 100 Area Vadose Zone at the Hanford Site

Energy Technology Data Exchange (ETDEWEB)

Dresel, P. Evan; Qafoku, Nikolla; McKinley, James P.; Fruchter, Jonathan S.; Ainsworth, Calvin C.; Liu, Chongxuan; Ilton, Eugene S.; Phillips, J. L.

2008-07-16

The major objectives of the proposed study were to: 1.) determine the leaching characteristics of hexavalent chromium [Cr(VI)] from contaminated sediments collected from 100 Area spill sites; 2.) elucidate possible Cr(VI) mineral and/or chemical associations that may be responsible for Cr(VI) retention in the Hanford Site 100 Areas through the use of i.) macroscopic leaching studies and ii.) microscale characterization of contaminated sediments; and 3.) provide information to construct a conceptual model of Cr(VI) geochemistry in the Hanford 100 Area vadose zone. In addressing these objectives, additional benefits accrued were: (1) a fuller understanding of Cr(VI) entrained in the vadose zone that will that can be utilized in modeling potential Cr(VI) source terms, and (2) accelerating the Columbia River 100 Area corridor cleanup by providing valuable information to develop remedial action based on a fundamental understanding of Cr(VI) vadose zone geochemistry. A series of macroscopic column experiments were conducted with contaminated and uncontaminated sediments to study Cr(VI) desorption patterns in aged and freshly contaminated sediments, evaluate the transport characteristics of dichromate liquid retrieved from old pipelines of the 100 Area; and estimate the effect of strongly reducing liquid on the reduction and transport of Cr(VI). Column experiments used the < 2 mm fraction of the sediment samples and simulated Hanford groundwater solution. Periodic stop-flow events were applied to evaluate the change in elemental concentration during time periods of no flow and greater fluid residence time. The results were fit using a two-site, one dimensional reactive transport model. Sediments were characterized for the spatial and mineralogical associations of the contamination using an array of microscale techniques such as XRD, SEM, EDS, XPS, XMP, and XANES. The following are important conclusions and implications. Results from column experiments indicated that most

An approach to quantify sources, seasonal change, and biogeochemical processes affecting metal loading in streams: Facilitating decisions for remediation of mine drainage

Science.gov (United States)

Kimball, B.A.; Runkel, R.L.; Walton-Day, K.

2010-01-01

Historical mining has left complex problems in catchments throughout the world. Land managers are faced with making cost-effective plans to remediate mine influences. Remediation plans are facilitated by spatial mass-loading profiles that indicate the locations of metal mass-loading, seasonal changes, and the extent of biogeochemical processes. Field-scale experiments during both low- and high-flow conditions and time-series data over diel cycles illustrate how this can be accomplished. A low-flow experiment provided spatially detailed loading profiles to indicate where loading occurred. For example, SO42 - was principally derived from sources upstream from the study reach, but three principal locations also were important for SO42 - loading within the reach. During high-flow conditions, Lagrangian sampling provided data to interpret seasonal changes and indicated locations where snowmelt runoff flushed metals to the stream. Comparison of metal concentrations between the low- and high-flow experiments indicated substantial increases in metal loading at high flow, but little change in metal concentrations, showing that toxicity at the most downstream sampling site was not substantially greater during snowmelt runoff. During high-flow conditions, a detailed temporal sampling at fixed sites indicated that Zn concentration more than doubled during the diel cycle. Monitoring programs must account for diel variation to provide meaningful results. Mass-loading studies during different flow conditions and detailed time-series over diel cycles provide useful scientific support for stream management decisions.

Integrated remediation of soil and groundwater

International Nuclear Information System (INIS)

Dykes, R.S.; Howles, A.C.

1992-01-01

Remediation of sites contaminated with petroleum hydrocarbons and other organic chemicals frequently focuses on a single phase of the chemical in question. This paper describes an integrated approach to remediation involving selection of complimentary technologies designed to create a remedial system which achieves cleanup goals in affected media in the shortest possible time consistent with overall environmental protection

PLANT INVASIONS IN RHODE ISLAND RIPARIAN ZONES

Science.gov (United States)

The vegetation in riparian zones provides valuable wildlife habitat while enhancing instream habitat and water quality. Forest fragmentation, sunlit edges, and nutrient additions from adjacent development may be sources of stress on riparian zones. Landscape plants may include no...

Bioventing in the subarctic: Field scale implementation of soil heating to allow in situ vadose zone biodegradation throughout the year

International Nuclear Information System (INIS)

Oram, D.E.; Winters, A.T.; Winsor, T.R.

1994-01-01

Bioventing is a technique of in situ bioremediation of contaminants in unsaturated zone soils that has advantages over other technologies such as soil vapor extraction. At locations where off-gas treatment would be required, bioventing can be a more cost-effective method of remediation. Using bioventing to remediate petroleum hydrocarbons in the vadose zone soils in extremely cold climates may be augmented by heating the subsurface soils. The US Air Force has conducted a bioventing feasibility study at Eielson Air Force Base since 1991. The feasibility study evaluated different methods of heating soils to maintain biodegradation rates through the winter. Results from this study were used to optimize the design of a full-scale bioventing system that incorporated a soil heating system. The system installed consists of the typical components of a bioventing system including an air injection blower, a system to distribute air in the vadose zone, and a monitoring system. To maintain biodegradation at a constant rate throughout the year, soil heating and temperature monitoring systems were also installed. Results to date indicate that summer soil temperatures and biodegradation of hydrocarbons have been maintained through the winter

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)

Plume persistence caused by back diffusion from thin clay layers in a sand aquifer following TCE source-zone hydraulic isolation.

Science.gov (United States)

Parker, Beth L; Chapman, Steven W; Guilbeault, Martin A

2008-11-14

This paper concludes that back diffusion from one or a few thin clayey beds in a sand aquifer can cause contaminant persistence above MCLs in a sand aquifer long after the source zone initially causing the plume is isolated or removed. This conclusion is based on an intensive case study of a TCE contaminated site in Florida, with the processes evaluated using numerical modeling. At this site, the TCE DNAPL zone formed decades ago, and was hydraulically isolated by means of an innovative system performing groundwater extraction, treatment and re-injection. Treated water is re-injected in a row of injection wells situated a short distance downgradient of the extraction wells, creating a clean-water displacement front to efficiently flush the downgradient plume. This scheme avoids the creation of stagnation zones typical of most groundwater pump-and-treat systems, thereby minimizing the time for aquifer flushing and therefore downgradient cleanup. The system began operation in August 2002 and although the performance monitoring shows substantial declines in concentrations, detectable levels of TCE and degradation products persist downgradient of the re-injection wells, long after the TCE should have disappeared based on calculations assuming a nearly homogenous sand aquifer. Three hypotheses were assessed for this plume persistence: 1) incomplete source-zone capture, 2) DNAPL occurrence downgradient of the re-injection wells, and 3) back diffusion from one or more thin clay beds in the aquifer. After careful consideration, the first two hypotheses were eliminated, leaving back diffusion as the only plausible hypothesis, supported by detailed measurements of VOC concentrations within and near the clay beds and also by numerical model simulations that closely represent the field site hydrogeologic conditions. The model was also used to simulate a more generalized, hypothetical situation where more thin clayey beds occur in a sand aquifer with an underlying aquitard

Smouldering (thermal) remediation of soil contaminated with industrial organic liquids: novel insights into heat transfer and kinetics uncovered by integrating experiments and modelling

Science.gov (United States)

Gerhard, J.; Zanoni, M. A. B.; Torero, J. L.

2017-12-01

Smouldering (i.e., flameless combustion) underpins the technology Self-sustaining Treatment for Active Remediation (STAR). STAR achieves the in situ destruction of nonaqueous phase liquids (NAPLs) by generating a self-sustained smouldering reaction that propagates through the source zone. This research explores the nature of the travelling reaction and the influence of key in situ and engineered characteristics. A novel one-dimensional numerical model was developed (in COMSOL) to simulate the smouldering remediation of bitumen-contaminated sand. This model was validated against laboratory column experiments. Achieving model validation depended on correctly simulating the energy balance at the reaction front, including properly accounting for heat transfer, smouldering kinetics, and heat losses. Heat transfer between soil and air was demonstrated to be generally not at equilibrium. Moreover, existing heat transfer correlations were found to be inappropriate for the low air flow Reynold's numbers (Re remediation systems. Therefore, a suite of experiments were conducted to generate a new heat transfer correlation, which generated correct simulations of convective heat flow through soil. Moreover, it was found that, for most cases of interest, a simple two-step pyrolysis/oxidation set of kinetic reactions was sufficient. Arrhenius parameters, calculated independently from thermogravimetric experiments, allowed the reaction kinetics to be validated in the smouldering model. Furthermore, a simple heat loss term sufficiently accounted for radial heat losses from the column. Altogether, these advances allow this simple model to reasonably predict the self-sustaining process including the peak reaction temperature, the reaction velocity, and the complete destruction of bitumen behind the front. Simulations with the validated model revealed numerous unique insights, including how the system inherently recycles energy, how air flow rate and NAPL saturation dictate contaminant

Remote sensing applications for coastal zone management

Digital Repository Service at National Institute of Oceanography (India)

Rao, L.V.G.

stream_size 4 stream_content_type text/plain stream_name Trg_Course_Coast_Zone_Manage_1993_5.pdf.txt stream_source_info Trg_Course_Coast_Zone_Manage_1993_5.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset...

Potential of biogenic hydrogen production for hydrogen driven remediation strategies in marine environments.

Science.gov (United States)

Hosseinkhani, Baharak; Hennebel, Tom; Boon, Nico

2014-09-25

Fermentative production of bio-hydrogen (bio-H2) from organic residues has emerged as a promising alternative for providing the required electron source for hydrogen driven remediation strategies. Unlike the widely used production of H2 by bacteria in fresh water systems, few reports are available regarding the generation of biogenic H2 and optimisation processes in marine systems. The present research aims to optimise the capability of an indigenous marine bacterium for the production of bio-H2 in marine environments and subsequently develop this process for hydrogen driven remediation strategies. Fermentative conversion of organics in marine media to H2 using a marine isolate, Pseudoalteromonas sp. BH11, was determined. A Taguchi design of experimental methodology was employed to evaluate the optimal nutritional composition in batch tests to improve bio-H2 yields. Further optimisation experiments showed that alginate-immobilised bacterial cells were able to produce bio-H2 at the same rate as suspended cells over a period of several weeks. Finally, bio-H2 was used as electron donor to successfully dehalogenate trichloroethylene (TCE) using biogenic palladium nanoparticles as a catalyst. Fermentative production of bio-H2 can be a promising technique for concomitant generation of an electron source for hydrogen driven remediation strategies and treatment of organic residue in marine ecosystems. Copyright © 2014 Elsevier B.V. All rights reserved.

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

Combining different frequencies for electrical heating of saturated and unsaturated soil zones

Energy Technology Data Exchange (ETDEWEB)

Roland, U.; Holzer, F.; Kopinke, F.D. [Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Engineering, Leipzig (Germany)

2011-10-15

In situ electrical heating of soil was studied applying different frequencies: low-frequency energy for resistive heating and radio-frequency energy for dielectric heating. Steep temperature gradients were observed for each heating mode under the condition of the coexistence of saturated and unsaturated soil zones. By combining the two heating modes, this undesired effect can be avoided, thus allowing efficient soil remediation especially when organic phases are accumulated at the capillary fringe. A parallel application of both frequencies was demonstrated as the most suitable method to reduce temperature gradients. By using electronic filters, both electric fields can be established by only one electrode array. This innovative concept is especially applicable for optimizing thermal remediation of light non-aqueous phase liquid contaminations or realizing thermally-enhanced electrokinetic removal of heavy metals. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Enhanced Attenuation of Unsaturated Chlorinated Solvent Source Zones using Direct Hydrogen Delivery

Science.gov (United States)

2013-01-01

solvents. This approach for bioremediation of unsaturated soils containing chlorinated solvents was originally proposed in a patent by Hughes et al...have been conducted on the use of hydrogen as an electron donor for the anaerobic bioremediation of saturated and unsaturated porous media (Evans and...proven to be very effective in remediating releases of petroleum products including gasoline, jet fuels, kerosene, and diesel fuel. Several field

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)

Interim measure conceptual design for remediation at the former CCC/USDA grain storage facility at Centralia, Kansas : pilot test and remedy implementation.

Energy Technology Data Exchange (ETDEWEB)

LaFreniere, L. M.; Environmental Science Division

2007-11-09

This document presents an Interim Measure Work Plan/Design for the short-term, field-scale pilot testing and subsequent implementation of a non-emergency Interim Measure (IM) at the site of the former grain storage facility operated by the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) in Centralia, Kansas. The IM is recommended to mitigate both (1) localized carbon tetrachloride contamination in the vadose zone soils beneath the former facility and (2) present (and potentially future) carbon tetrachloride contamination identified in the shallow groundwater beneath and in the immediate vicinity of the former CCC/USDA facility. Investigations conducted on behalf of the CCC/USDA by Argonne National Laboratory have demonstrated that groundwater at the Centralia site is contaminated with carbon tetrachloride at levels that exceed the Kansas Tier 2 Risk-Based Screening Level (RBSL) and the U.S. Environmental Protection Agency's maximum contaminant level of 5.0 {micro}g/L for this compound. Groundwater sampling and analyses conducted by Argonne under a monitoring program approved by the Kansas Department of Health and Environment (KDHE) indicated that the carbon tetrachloride levels at several locations in the groundwater plume have increased since twice yearly monitoring of the site began in September 2005. The identified groundwater contamination currently poses no unacceptable health risks, in view of the absence of potential human receptors in the vicinity of the former CCC/USDA facility. Carbon tetrachloride contamination has also been identified at Centralia in subsurface soils at concentrations on the order of the Kansas Tier 2 RBSL of 200 {micro}g/kg in soil for the soil-to-groundwater protection pathway. Soils contaminated at this level might pose some risk as a potential source of carbon tetrachloride contamination to groundwater. To mitigate the existing contaminant levels and decrease the potential future concentrations of

Research in Support of Remediation Activities at the Savannah River Site

International Nuclear Information System (INIS)

Seaman, J.C.; B.B. Looney and M.K. Harris

2007-01-01

The USDOE Savannah River Site (SRS), an 803-km 2 (310-mile 2 ) facility located south of Aiken, SC on the upper Atlantic Coastal Plain and bounded to the west by the Savannah River, was established in the 1950s for the production and refinement of nuclear materials. To fulfill this mission during the past 50 years SRS has operated five nuclear reactors, two large chemical separation areas, waste disposal facilities (landfills, waste ponds, waste tanks, and waste stabilization), and a large number of research and logistics support facilities. Contaminants of concern (COC) resulting from site operations include chlorinated solvents, radionuclides, metals, and metalloids, often found as complex mixtures that greatly complicate remediation efforts when compared with civilian industries. The objective of this article is to provide a description of the lithology and hydrostratigraphy of the SRS, as well as a brief history of site operations and research activities as a preface to the current special section of Vadose Zone Journal (VZJ) dedicated to SRS, focusing mainly on issues that are unique to the USDOE complex. Contributions to the special section reflect a diverse range of topics, from hydrologic tracer experiments conducted both within the vadose and saturated zones to studies specifically aimed at identifying geochemical processes controlling the migration and partitioning of specific contaminants (e.g., TCE, 137 Cs, U, and Pu) in SRS subsurface environments. Addressing the diverse environmental challenges of the SRS provides a unique opportunity to conduct both fundamental and applied research across a range of experimental scales. Hence, the SRS has been a pioneering force in several areas of environmental research and remediation, often through active interdisciplinary collaboration with researchers from other USDOE facilities, academic and federal institutions, and commercial entities

Localized sulfate-reducing zones in a coastal plain aquifer