WorldWideScience

Sample records for contaminated area remediation

  1. Avian Conservation Areas as a Proxy for Contaminated Soil Remediation.

    Science.gov (United States)

    Lin, Wei-Chih; Lin, Yu-Pin; Anthony, Johnathen; Ding, Tsun-Su

    2015-07-17

    Remediation prioritization frequently falls short of systematically evaluating the underlying ecological value of different sites. This study presents a novel approach to delineating sites that are both contaminated by any of eight heavy metals and have high habitat value to high-priority species. The conservation priority of each planning site herein was based on the projected distributions of eight protected bird species, simulated using 900 outputs of species distribution models (SDMs) and the subsequent application of a systematic conservation tool. The distributions of heavy metal concentrations were generated using a geostatistical joint-simulation approach. The uncertainties in the heavy metal distributions were quantified in terms of variability among 1000 realization sets. Finally, a novel remediation decision-making approach was presented for delineating contaminated sites in need of remediation based on the spatial uncertainties of multiple realizations and the priorities of conservation areas. The results thus obtained demonstrate that up to 42% of areas of high conservation priority are also contaminated by one or more of the heavy metal contaminants of interest. Moreover, as the proportion of the land for proposed remediated increased, the projected area of the pollution-free habitat also increased. Overall uncertainty, in terms of the false positive contamination rate, also increased. These results indicate that the proposed decision-making approach successfully accounted for the intrinsic trade-offs among a high number of pollution-free habitats, low false positive rates and robustness of expected decision outcomes.

  2. Remediation of contaminated areas. An overview of international guidance

    Energy Technology Data Exchange (ETDEWEB)

    Hedemann Jensen, Per

    1999-05-01

    The work described in this report has been performed as a part of the RESTRAT Project FI4P-CT95-0021a (PL 950128) co-funded by the Nuclear Fission Safety Programme of the European Commission. The RESTRAT project has the overall objective of developing generic methodologies for ranking restoration techniques as a function of contamination and site characteristics. The project includes analyses of existing remediation methodologies and contaminated sites, and is structured in the following steps: characterisation of relevant contaminated sites; identification and characterisation of relevant restoration techniques; assessment of the radiological impact; development and application of a selection methodology for restoration options; formulation of generic conclusions and development of a manual. The project is intended to apply to situations in which sites with nuclear installations have been contaminated with radioactive materials as a result of the operation of these installations. The areas considered for remedial measures include contaminated land areas, rivers and sediments in rivers, lakes, and sea areas. Criteria for clean-up of contaminated land and criteria for protection of the public against chronic exposure are being developed by Advisory Groups and Task Groups within the International Atomic Energy Agency (IAEA) and the International Commission on Radiological Protection (ICRP). This work has been reviewed and a status as of the beginning of 1998 is given. For illustrative purposes , the basic radiation protection principles of justification and optimisation have been applied to derive generic action levels for clean-up of residential areas contaminated with radioactive materials. These generic action levels are based upon cost-benefit analyses that include avertable doses and monetary costs of clean-up. (au) 3 tabs., 4 ills., 10 refs. (Internet)

  3. Contaminant plumes containment and remediation focus area. Technology summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    EM has established a new approach to managing environmental technology research and development in critical areas of interest to DOE. The Contaminant Plumes Containment and Remediation (Plumes) Focus Area is one of five areas targeted to implement the new approach, actively involving representatives from basic research, technology implementation, and regulatory communities in setting objectives and evaluating results. This document presents an overview of current EM activities within the Plumes Focus Area to describe to the appropriate organizations the current thrust of the program and developing input for its future direction. The Plumes Focus Area is developing remediation technologies that address environmental problems associated with certain priority contaminants found at DOE sites, including radionuclides, heavy metals, and dense non-aqueous phase liquids (DNAPLs). Technologies for cleaning up contaminants of concern to both DOE and other federal agencies, such as volatile organic compounds (VOCs), polychlorinated biphenyls (PCBs), and other organics and inorganic compounds, will be developed by leveraging resources in cooperation with industry and interagency programs.

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

    Energy Technology Data Exchange (ETDEWEB)

    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 {sup 90}Sr, {sup 3}H, and {sup 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.

  5. Solutions Remediate Contaminated Groundwater

    Science.gov (United States)

    2010-01-01

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

  6. How short rotation forest crops can be used for sustainable remediation of contaminated areas

    Energy Technology Data Exchange (ETDEWEB)

    Thiry, I.

    1996-09-18

    In large territories of the CIS, it becomes obvious from the factual consequences of the Chernobyl environmental contamination that no successful remediation actions can be achieved without considering realistic technical and economical issues. In these conditions, the Short Rotation Forestry concept for energy purposes is proposed as an alternative and integrated approach for the recovery of agricultural practices on waste farm land. This corrective option will be examined with respect to this ecological, economical, and social relevancy. Different aspects of the culture in contaminated areas and of energy production from biomass remain to be investigated, developed and validated in the light of radiation protection criteria. In particular, attention will be drawn on the opportunity of this new concept to be integrated in the development of the site remediation research activities at SCK.CEN.

  7. The cost and benefit analysis of a contaminated area remediation: case study of dose level selection

    Energy Technology Data Exchange (ETDEWEB)

    Lauria, D.C. [Instituto de Radioproteccion e Dosimetria- IRD/CNEN, Av. Salvador Allende s/n, Barra de Tijuca, Rio de Janeiro- RJ (Brazil)]. e-mail: dejanira@ird.gov.br

    2006-07-01

    In recent years there has been an increasing awareness of the radiological impact of non-nuclear industries that extract and/or process ores and minerals containing naturally occurring radioactive material (NORM). Without radiological rules, these industrial activities may result in significant radioactive contamination of installations and sites. Depending on the potential hazardous to the environment and public health, the radioactive contaminated sites may require remediation. The extent of the site cleanup is a function of the size, localization, complexity, potential risks and on possible future uses envisioned for the site. Since worker and public health, public anxiety and economics factors are involved; the selection of an appropriate dose level can be quite complicated. This paper discusses the selection of a dose level criterion to remedy a site, which was contaminated by wastes from monazite processing. The site is located in the Sao Paulo city; the most densely populated Brazilian City. In its 60,000 square meters of area, a preliminary survey showed contaminated zones covering an area of 6,500 square meters. In some places, contamination was found below the superficial layer of the soil, being the radionuclide vertical distribution not uniform. The {sup 228} Ra soil activity concentration reached values up to 33,000 Bq/kg while those for {sup 226} Ra reached values up to 6,700 Bq/kg. Based on pathway analysis model and considering both the current land use and a hypothetical residential scenario, the residual contamination levels of radionuclides in soil have been derived for dose values of 10 mSv/y (dose level for intervention), 5 mSv/y, 3 mSv/y, 1 mSv/y (dose limit for practices) and 0.3 mSv/y (dose constraint for practices). An optimized value o f annual dose of about 5 mSv/y would be a good option for intervention level, but taking into account the public concern and anxiety, the site location and size, and the remediation costs, it is suggested

  8. Remediation of heavy metal contaminated sites in the Venice lagoon and conterminous areas (Northern Italy)

    Science.gov (United States)

    Bini, Claudio; Wahsha, Mohammad; Fontana, Silvia; Maleci, Laura

    2013-04-01

    The lagoon of Venice and the conterminous land are affected by heavy contamination of anthropogenic origin, and for this reason the whole area has been classified as site of national interest, and must be restored. Heavy metals (As, Cd, Cr, Cu, Hg, Mn, Pb, Sb, Se, Zn) and organic compounds (IPA, PCB, Dioxine) have been identified as the main contaminants at various sites, owing to agriculture and industrial wastes discharged on soils and convoyed to the lagoon. Five case studies of soil remediation are here reported. S. Giuliano is a former palustrine area reclaimed since the 60's with various human transported materials (HTM). In this area, hot spots overpassing the reference limits for residential and green areas have been recorded for Cd, Cu, Pb, Zn and IPA. Campalto is a site bordering the Venice lagoon and subjected to oscillating water level, that enhances metal mobility; diffuse contamination by heavy metals, particularly Pb, has been recorded at this site, utilized since 30 years for military and sport (skate) activities. Marghera is dramatically famous for its numerous factories and for oil refineries that affected the lagoon sediments since the 50's. Sediments proved heavily contaminated by As (up to 137 mgkg-1), Cd (57 mgkg-1), Hg (30mgkg-1), Ni, Pb (700 mgkg-1), Zn (5818 mgkg-1). Murano is a small island where many glass factories (the most famous all over the world) are running since XIII century. Glass is stained with several metals and, moreover, some substances are used to regulate fusion temperature, purity, etc., and therefore the surrounding environment is heavily contaminated by these substances. Mean concentrations of As (429 mgkg-1), Cd (1452 mgkg-1), Pb (749 mgkg-1), Zn (1624 mgkg-1), Se (341 mgkg-1), Sb (74 mgkg-1) widely overpass the reference values for both residential and industrial areas in national guidelines. Molo Serbatoi is a former oil container currently under restoration in the port of Venice. Soil contamination by As, Hg, Zn and

  9. Phytotechnologies: remediation of environmental contaminants

    National Research Council Canada - National Science Library

    Anjum, Naser A

    2013-01-01

    .... The book offers an evaluation of the known plant species for their different roles in phytotechnological applications in relation to remediation of varied environmental contaminants and also explores...

  10. Remediation Technologies Eliminate Contaminants

    Science.gov (United States)

    2012-01-01

    All research and development has a story behind it, says Jacqueline Quinn, environmental engineer at Kennedy Space Center. For Quinn, one such story begins with the Saturn 1B launch stand at Kennedy and ends with a unique solution to a challenging environmental problem. Used in a number of Apollo missions and during the Skylab program, the Saturn 1B launch stand was dismantled following the transition to the Space Shuttle Program and stored in an open field at Kennedy. Decades later, the Center s Environmental Program Office discovered evidence of chemicals called polychlorinated biphenyls (PCBs) in the field s soil. The findings were puzzling since PCBs a toxin classified as a probable carcinogen by the Environmental Protection Agency (EPA) have been banned in the United States since 1979. Before the ban, PCBs were commonly used in transformer oils that leached into the ground when the oils were changed out and dumped near transformer sites, but there were no electrical transformers near the dismantled stand. It soon became apparent that the source of the PCBs was the launch stand itself. Prior to the ban, PCBs were used extensively in paints to add elasticity and other desirable characteristics. The PCB-laden paint on the Saturn 1B launch stand was flaking off into the field s soil. Nobody knew there were PCBs in the paint, says Quinn, noting that the ingredient was not monitored carefully when it was in use in 1960s. In fact, she says, the U.S. EPA was not even established until 1970, a year after Neil Armstrong first set foot on the Moon. Nobody knew any better at the time, Quinn says, but today, we have the responsibility to return any natural environmental media to as close to pristine a condition as possible. Quinn, fellow engineer Kathleen Loftin, and other Kennedy colleagues already had experience developing unprecedented solutions for environmental contamination; the team invented the emulsified zero-valent iron (EZVI) technology to safely treat

  11. Biological Remediation of Petroleum Contaminants

    Science.gov (United States)

    Kuhad, Ramesh Chander; Gupta, Rishi

    Large volumes of hazardous wastes are generated in the form of oily sludges and contaminated soils during crude oil transportation and processing. Although many physical, chemical and biological treatment technologies are available for petroleum contaminants petroleum contaminants in soil, biological methods have been considered the most cost-effective. Practical biological remediation methods typically involve direct use of the microbes naturally occurring in the contaminated environment and/or cultured indigenous or modified microorganisms. Environmental and nutritional factors, including the properties of the soil, the chemical structure of the hydrocarbon(s), oxygen, water, nutrient availability, pH, temperature, and contaminant bioavailability, can significantly affect the rate and the extent of hydrocarbon biodegradation hydrocarbon biodegradation by microorganisms in contaminated soils. This chapter concisely discusses the major aspects of bioremediation of petroleum contaminants.

  12. Subsurface contaminants focus area

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

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

  13. [Feasibility of applying ornamental plants in contaminated soil remediation].

    Science.gov (United States)

    Liu, Jia-Nü; Zhou, Qi-Xing; Sun, Ting; Wang, Xiao-Fei

    2007-07-01

    Phytoremediation is one of the effective ways in resolving problems of contaminated soils, but limited hyperaccumulation plant species were reported and documented. This shortage could be offset if remediation plants can be screened out from various ornamental plants. In addition, such doing can beautify the environment while bring some economic effects. Starting from the importance of phytoremediation, this paper generalized the characters and standards of remediation plants. Through describing the resources of ornamental plants and their functions on environmental protection, particularizing their superiorities to other plants, and analyzing their endurance, accumulation traits and remediation types, the feasibility of applying ornamental plants in the practices of contaminated soil remediation was discussed. To screening out hyperaccumulators from ornamental plants would be an entirely new research area in the remediation of contaminated soils.

  14. Remediation of heavy metal contaminated soil | Nanda |

    African Journals Online (AJOL)

    Remediation of heavy metal contaminated soil. ... in intensive research aiming at understanding metal interactions in soil and their removal in an efficient way. ... This paper investigates the plant-microbial interactions in reclaiming the metal ...

  15. Tools for forming strategies for remediation of forests and park areas in northern Europe after radioactive contamination: background and techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, L. [Swedish Radiation Protection Authority, SSI (Sweden); Rantavaara, A. [Radiation and Nuclear Safety Autority, STUK (Finland); Andersson, K. [Risoe National Lab., Roskilde (Denmark); Roed, J. [Risoe National Lab., Roskilde (Denmark)

    2002-01-01

    This report compiles background information that can be used in planning appropriate countermeasures for forest and park areas in Denmark, Sweden, Finland and Norway, in case a nuclear accident results in large-scale contamination of forests. The information is formulated to inform the forestry sector and radiation protection experts about the practicality of both forest management techniques and mechanical cleanup methods, for use in their planning of specific strategies that can lead to an optimal use of contaminated forests. Decisions will depend on the site and the actual situation after radioactive deposition to forested areas, but the report provides background information from investigations performed before an accident occurs that will make the process more effective. The report also discusses the radiological consequences of producing energy from biomass contaminated by a major nuclear accident, both in the context of normal bio-fuel energy production and as a means of reducing potentially severe environmental problems in the forest by firing power plants with highly contaminated forest biomass. (au)

  16. Remediation Technology of Contaminated Areas with Organochlorines: A Preliminary Evaluation Seeking Potential Applications on the Site of Street Capua, Santo André - SP

    Directory of Open Access Journals (Sweden)

    Mauro Silva Ruiz

    2012-12-01

    Full Text Available This paper is aimed to analyze the use of remediation technologies for areas contaminated with organochlorine based on a literature review and discussions with specialists. The remediation technologies analyzed were bioremediation, phytoremediation, nanotechnology, chemical oxidation, and thermal desorption. The purpose is to identify and compare “key problems” for each of these technologies envisaging the use of one or more of these them f or the remediation of the Capua Street site in Santo André, SP. Four databases were used in the preliminary literature review: Scopus, SciELO, Web of Science, and Science Direct. A survey questionnaire was designed to gather information on publications of scientific papers and patents, specific uses of these technologies by companies, and cases of application. Since the quality of the data and information obtained from this questionnaire application was not satisfactory, a new research approach for complementing them was undertaken. For this purpose, the Web of Science was selected as the most adequate data basis to carry out this second survey. However, it was realized that even for this database - that is reference for evaluating academic institutions, researchers and maturity of technologies – bias coming from the original data source can affect the survey results. Moreover, as the number of keywords used in the research consisted of generic terms for each technology, it can also be assumed that if some authors have used very specific terms, a small amount of work published by them would possibly have been misrepresented in the final result.

  17. Ground-water, surface-water, and bottom-sediment contamination in the O-field area, Aberdeen Proving Ground, Maryland, and the possible effects of selected remedial actions on ground water

    Science.gov (United States)

    Vroblesky, Don A.; Lorah, Michelle M.; Oliveros, James P.

    1995-01-01

    Disposal of munitions and chemical-warfare substances has introduced inorganic and organic contaminants to the ground water, surface water, and bottom sediment at O-Field, in the Edgewood area of Aberdeen Proving Ground, Maryland. Contaminants include chloride, arsenic, transition metals, chlorinated aliphatic hydrocarbons, aromatic compounds, and organosulfur and organophosphorus compounds. The hydrologic effects of several remedial actions were estimated by use of a ground-water-flow model. The remedial actions examined were an impermeable covering, encapsulation, subsurface barriers, a ground-water drain, pumping of wells to manage water levels or to remove contaminated ground water for treatment, and no action.

  18. Remediation Technology for Contaminated Groundwater

    Science.gov (United States)

    Bioremediation is the most commonly selected technology for remediation of ground water at Superfund sites in the USA. The next most common technology is Chemical treatment, followed by Air Sparging, and followed by Permeable Reactive Barriers. This presentation reviews the the...

  19. Phytotechnologies: remediation of environmental contaminants

    National Research Council Canada - National Science Library

    Anjum, Naser A

    2013-01-01

    "This book highlights the use of the natural-inherent traits of plants and associated bacteria and microbes to exclude, accumulate or metabolize toxic contaminants where they contribute significantly...

  20. Remediation of oil-contaminated soil in Arctic Climate

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Fritt-Rasmussen, Janne; Rodrigo, Ana P.

    Oil spill is a problem in towns in Greenland, where oil is used for heating and transport. The problem may increase in the future with expected oil exploitation in Greenlandic marine areas and related terrestrial activities. Oil undergoes natural microbial degradation in which nutrients...... have been made with excavated oil-contaminated soil from the Greenlandic town Sisimiut to study different low-tech and low-cost solutions for remediation of oil-contamination....

  1. Remediation of oil-contaminated soil in Arctic Climate

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Fritt-Rasmussen, Janne; Rodrigo, Ana

    Oil spill is a problem in towns in Greenland, where oil is used for heating and transport. The problem may increase in the future with expected oil exploitation in Greenlandic marine areas and related terrestrial activities. Oil undergoes natural microbial degradation in which nutrients....... Experiments have been made with excavated oil-contaminated soil from the Greenlandic town Sisimiut to study different low-tech and low-cost solutions for remediation of oil-contamination...

  2. Remediation technologies for oil-contaminated sediments.

    Science.gov (United States)

    Agarwal, Ashutosh; Liu, Yu

    2015-12-30

    Oil-contaminated sediments pose serious environmental hazards for both aquatic and terrestrial ecosystems. Innovative and environmentally compatible technologies are urgently required to remove oil-contaminated sediments. In this paper, various physical, chemical and biological technologies are investigated for the remediation of oil-contaminated sediments such as flotation and washing, coal agglomeration, thermal desorption, ultrasonic desorption, bioremediation, chemical oxidation and extraction using ionic liquids. The basic principles of these technologies as well as their advantages and disadvantages for practical application have been discussed. A combination of two or more technologies is expected to provide an innovative solution that is economical, eco-friendly and adaptable.

  3. Feasibility Study of Contamination Remediation at Naval Weapons Station, Concord, California. Volume 1. Remedial Action Alternatives.

    Science.gov (United States)

    1988-09-01

    few years, particularly along the Port Chicago Highway across from the main gate of NWS Concord. Phillips Petroleum Company and Monsanto--V 2.23 %" r...acci- dental disturbance of the monofill. ,p Grading and Revegetation. See Alternative 3-3A. Operation and Maintenance of Remediation Area. See...washing process; b. Site preparation and support facilities; c. Excavation of contaminated materials; d. Classification of contaminated materialL ; e

  4. Some aspects of remediation of contaminated soils

    Science.gov (United States)

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

    2014-05-01

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

  5. Remediation of Groundwater Contaminated by Nuclear Waste

    Science.gov (United States)

    Parker, Jack; Palumbo, Anthony

    2008-07-01

    A Workshop on Accelerating Development of Practical Field-Scale Bioremediation Models; An Online Meeting, 23 January to 20 February 2008; A Web-based workshop sponsored by the U.S. Department of Energy Environmental Remediation Sciences Program (DOE/ERSP) was organized in early 2008 to assess the state of the science and knowledge gaps associated with the use of computer models to facilitate remediation of groundwater contaminated by wastes from Cold War era nuclear weapons development and production. Microbially mediated biological reactions offer a potentially efficient means to treat these sites, but considerable uncertainty exists in the coupled biological, chemical, and physical processes and their mathematical representation.

  6. Mapping Contaminant Remediation with Electrical Resistivity Tomography

    Science.gov (United States)

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

    2014-12-01

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

  7. ELECTROKINETIC REMEDIATION STUDY FOR CADMIUM CONTAMINATED SOIL

    Directory of Open Access Journals (Sweden)

    P. Bala Ramudu

    2007-09-01

    Full Text Available This paper presents the results of an experimental research undertaken to evaluate different purging solutions to enhance the removal of cadmium from spiked contaminated field soil by electrokinetic remediation. Three experiments were conducted when soil was saturated with deionised water and subsequently deionised water, ammonium citrate and sodium citrate were used as purging solutions at anode end. One experiment was conducted when the soil was saturated with ammonium citrate and itself was used as the purging solution. Results showed that 49% reduction of cadmium concentration was achieved in the case of soil saturated (washed with ammonium citrate as well as purging solution also was ammonium citrate. The soil pH and washing solutions were the most important factors in controlling the removal of cadmium in electrokinetic remediation process.

  8. Mechanochemical remediation of PCB contaminated soil.

    Science.gov (United States)

    Wang, Haizhu; Hwang, Jisu; Huang, Jun; Xu, Ying; Yu, Gang; Li, Wenchao; Zhang, Kunlun; Liu, Kai; Cao, Zhiguo; Ma, Xiaohui; Wei, Zhipeng; Wang, Quhui

    2017-02-01

    Soil contaminated by polychlorinated biphenyls (PCBs) is a ubiquitous problem in the world, which can cause significant risks to human health and the environment. Mechanochemical destruction (MCD) has been recognized as a promising technology for the destruction of persistent organic pollutants (POPs) and other organic molecules in both solid waste and contaminated soil. However, few studies have been published about the application of MCD technology for the remediation of PCB contaminated soil. In the present study, the feasibility of destroying PCBs in contaminated soil by co-grinding with and without additives in a planetary ball mill was investigated. After 4 h milling time, more than 96% of PCBs in contaminated soil samples were destroyed. The residual concentrations of PCBs decreased from 1000 mg/kg to below the provisional Basel Convention limit of less than 50 mg/kg. PCDD/F present in the original soil at levels of 4200 ng TEQ/kg was also destroyed with even a slightly higher destruction efficiency. Only minor dechlorinations of the PCBs were observed and the destruction of the hydrocarbon skeleton is proposed as the main degradation pathway of PCBs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Remediation of PCB contaminated soils at Saglek, Labrador

    Energy Technology Data Exchange (ETDEWEB)

    Maskell, B.; Bordin, D. [Bennett Environmental Inc., Oakville, ON (Canada)

    2005-07-01

    Polychlorinated biphenyl (PCB) contaminated soils were discovered in Saglek in 1986. This paper describes a contract awarded to Bennett Environmental Inc., by the Department of National Defense for the removal of all contaminated soils and debris in the area. Key tasks included removal of all stockpiles of PCB contaminated soil; collection, cleaning and sorting of debris for containerization and removal; remediation of potential contaminated soils beneath the stockpiles; and reinstatement of the staging and clean stone deposition zone area to its natural state. Planning of the project was outlined, including details of partnering sessions and workshops, as well as details of community meetings held in Nain. Details of startup and pre-environmental monitoring were also provided. An outline of the containerization unit used during the project was presented, as well as ship cycle times and soil sampling procedures. Washing and water treatment procedures were reviewed, as well as details of the on-site laboratory, equipped with personal exposure monitoring; an ambient air monitoring network; water sampling and analysis; and continuous monitoring to assess potential exposure to PCB to conform to alarm levels and implement mitigation measures. Shipping procedures were reviewed as well as soil treatment processes at a facility in Cornwall, Ontario. It was concluded that the remediation of the site was successful. All contaminated material was removed and treated. 1 ref., 4 figs.

  10. Predicting the phytoextraction duration to remediate heavy metal contaminated soils

    NARCIS (Netherlands)

    Koopmans, G.F.; Römkens, P.F.A.M.; Song, J.; Temminghoff, E.J.M.; Japenga, J.

    2007-01-01

    The applicability of phytoextraction to remediate soils contaminated with heavy metals (HMs) depends on, amongst others, the duration before remediation is completed. The impact of changes in the HM content in soil occurring during remediation on plant uptake has to be considered in order to obtain

  11. Predicting the phytoextraction duration to remediate heavy metal contaminated soils

    NARCIS (Netherlands)

    Koopmans, G.F.; Römkens, P.F.A.M.; Song, J.; Temminghoff, E.J.M.; Japenga, J.

    2007-01-01

    The applicability of phytoextraction to remediate soils contaminated with heavy metals (HMs) depends on, amongst others, the duration before remediation is completed. The impact of changes in the HM content in soil occurring during remediation on plant uptake has to be considered in order to obtain

  12. 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.

  13. Using biochar for remediation of soils contaminated with heavy metals and organic pollutants.

    Science.gov (United States)

    Zhang, Xiaokai; Wang, Hailong; He, Lizhi; Lu, Kouping; Sarmah, Ajit; Li, Jianwu; Bolan, Nanthi S; Pei, Jianchuan; Huang, Huagang

    2013-12-01

    Soil contamination with heavy metals and organic pollutants has increasingly become a serious global environmental issue in recent years. Considerable efforts have been made to remediate contaminated soils. Biochar has a large surface area, and high capacity to adsorb heavy metals and organic pollutants. Biochar can potentially be used to reduce the bioavailability and leachability of heavy metals and organic pollutants in soils through adsorption and other physicochemical reactions. Biochar is typically an alkaline material which can increase soil pH and contribute to stabilization of heavy metals. Application of biochar for remediation of contaminated soils may provide a new solution to the soil pollution problem. This paper provides an overview on the impact of biochar on the environmental fate and mobility of heavy metals and organic pollutants in contaminated soils and its implication for remediation of contaminated soils. Further research directions are identified to ensure a safe and sustainable use of biochar as a soil amendment for remediation of contaminated soils.

  14. Overview of innovative remediation of emerging contaminants

    Science.gov (United States)

    Keller, A. A.; Adeleye, A. S.; Huang, Y.; Garner, K.

    2015-12-01

    The application of nanotechnology in drinking water treatment and pollution cleanup is promising, as demonstrated by a number of field-based (pilot and full scale) and bench scale studies. A number of reviews exist for these nanotechnology-based applications; but to better illustrate its importance and guide its development, a direct comparison between traditional treatment technologies and emerging approaches using nanotechnology is needed. In this review, the performances of traditional technologies and nanotechnology for water treatment and environmental remediation were compared with the goal of providing an up-to-date reference on the state of treatment techniques for researchers, industry, and policy makers. Pollutants were categorized into broad classes, and the most cost-effective techniques (traditional and nanotechnology-based) in each category reported in the literature were compared. Where information was available, cost and environmental implications of both technologies were also compared. Traditional treatment technologies were found to currently offer the most cost-effective choices for removal of several common pollutants from drinking water and polluted sites. Nano-based techniques may however become important in complicated remediation conditions and meeting increasingly stringent water quality standards, especially in removal of emerging pollutants and low levels of contaminants. We also discuss challenges facing environmental application of nanotechnology were also discussed and potential solutions.

  15. Information gap decision support for contaminant remediation

    Science.gov (United States)

    Vesselinov, V. V.; O'Malley, D.

    2013-12-01

    Uncertainty quantifications and decision analyses under severe lack of information are ubiquitous in every applied field of engineering, policy, and science. A severe lack of information precludes our ability to determine unbiased probabilistic distributions for model parameters and model predictions; therefore, model and decision uncertainties due to a severe lack of information cannot be characterized probabilistically. To circumvent this problem, information gap (info-gap) theory has been developed to explicitly recognize and quantify the implications of information gaps in decision making. Here we present a decision analysis based on info-gap theory developed for a source identification problem where the locations and mass fluxes of contaminants impacting groundwater resources are unknown. The problem is characterized with a lack of information related to (1) model parameters representing contaminant migration in the aquifer, and (2) observed contamination concentration in the existing monitoring wells. These two sources of uncertainty are coupled through an inverse model where the observed concentrations are applied to estimate model parameters. The decision goal is based on contaminant predictions at points of compliance. The decision analysis is demonstrated for synthetic and real-world test cases. The applied uncertainty-quantification, decision-support techniques and computational algorithms are implemented in code MADS (Model Analyses for Decision Support; http://mads.lanl.gov). MADS is C/C++ code that provides a framework for model-based decision support. MADS performs various types of model analyses including sensitivity analysis, parameter estimation, uncertainty quantification, model calibration, selection and averaging. To perform the analyses, MADS can be coupled with any external simulators. Our efforts target development of an interactive computer-based Decision Support System (DSS) that will help domain scientist, managers, regulators, and

  16. Modelling remediation options for urban contamination situations

    DEFF Research Database (Denmark)

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

    2009-01-01

    The impact on a population from an event resulting in dispersal and deposition of radionuclides in an urban area could be significant, in terms of both the number of people affected and the economic costs of recovery. The use of computer models for assessment of urban contamination situations...

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

    Science.gov (United States)

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

    2009-12-01

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

  18. 'Gold standard' for remediation of WTC contamination.

    Science.gov (United States)

    2004-01-01

    The events of September 11, 2001 and thereafter resulted in arguably the worst environmental disaster in the history of New York City. Particulate matter and combustion by-products containing asbestos, lead, mercury, dioxin, PAHs, and other toxic substances, not only affected rescue and recovery workers but also infiltrated thousands of residences and workplaces. Government agencies did not acknowledge responsibility for residential indoor environmental quality until eight months later, and still have not accepted responsibility for indoor environmental quality in commercial or government buildings. In May 2002, 200 representatives from 38 community, labor, environmental, and public health organizations met to discuss unmet post-9/11 public health needs. They established a technical working group to press the Environmental Protection Agency to expand and improve its proposals for the cleanup of Lower Manhattan. This 2002 document, "The 'Gold Standard' for Remediation of WTC Contamination," articulates the environmental health concerns and suggestions of grassroots organizations active in 9/11 response efforts at that time.

  19. [Research on the Screening Method of Soil Remediation Technology at Contaminated Sites and Its Application].

    Science.gov (United States)

    Bai, Li-ping; Luo, Yun; Liu, Li; Zhou, You-ya; Yan, Zeng-guang; Li, Fa-sheng

    2015-11-01

    Soil remediation technology screening is an important procedure in the supervision of contaminated sites. The efficiency and costs of contaminated site remediation will be directly affected by the applicability of soil remediation technology. The influencing factors include characteristics of contaminants, site conditions, remediation time and costs should be considered to determine the most applicable remediation technology. The remediation technology screening was commonly evaluated by the experienced expert in China, which limited the promotion and application of the decision making method. Based on the supervision requirements of contaminated sites and the research status at home and abroad, the screening method includes preliminary screening and explicit evaluation was suggested in this paper. The screening index system was constructed, and the extension theory was used to divide the technology grade. The extension theory could solve the problem of human interference in the evaluation process and index value assignment. A chromium residue contaminated site in China was selected as the study area, and the applicable remediation technologies were suggested by the screening method. The research results could provide a scientific and technological support for the supervision and management of contaminated sites in China.

  20. In-situ remediation of contaminated sediments : conceivable and feasible?!

    NARCIS (Netherlands)

    Joziasse, J.; Gun, J. van der

    2000-01-01

    In-situ remediation has assumed large proportions in dealing with terrestrial soil pollution. Although implementation of in-situ remediation for contaminated sediments is restricted by the fact that dredging is necessary for nautical or water management reasons, it should not be discarded

  1. Modelling the long-term consequences of a hypothetical dispersal of radioactivity in an urban area including remediation alternatives

    DEFF Research Database (Denmark)

    Thiessen, K.M.; Andersson, Kasper Grann; Batandjieva, B.

    2009-01-01

    The Urban Remediation Working Group of the International Atomic Energy Agency's EMRAS (Environmental Modelling for Radiation Safety) program was organized to address issues of remediation assessment modelling for urban areas contaminated with dispersed radionuclides. The present paper describes t...

  2. Biosurfactant-facilitated remediation of metal-contaminated soils.

    OpenAIRE

    R. M. Miller

    1995-01-01

    Bioremediation of metal-contaminated wastestreams has been successfully demonstrated. Normally, whole cells or microbial exopolymers are used to concentrate and/or precipitate metals in the wastestream to aid in metal removal. Analogous remediation of metal-contaminated soils is more complex because microbial cells or large exopolymers do not move freely through the soil. The use of microbially produced surfactants (biosurfactants) is an alternative with potential for remediation of metal-con...

  3. Electrokinetic remediation of oil-contaminated soils.

    Science.gov (United States)

    Korolev, Vladimir A; Romanyukha, Olga V; Abyzova, Anna M

    2008-07-01

    This investigation was undertaken to determine the factors influencing electrokinetic remediation of soils from petroleum pollutants. The remediation method was applied in two versions: (i) static and (ii) flowing, when a sample was washed with leaching solution. It was found that all the soils studied can be purified using this technique. It was also observed that the mineral and grain-size composition of soils, their properties, and other parameters affect the remediation efficiency. The static and flowing versions of the remediation method removed 25-75% and 90-95% of the petroleum pollutants, respectively from the soils under study.

  4. Lead Contamination of Soil Along Road and Its Remediation

    Institute of Scientific and Technical Information of China (English)

    徐佩; 廖超林

    2004-01-01

    With a rapid development of road systems and an associated drastic increase in number of automobiles, the traffic has induced more and more obvious environmental pollution such as noise, dust, emission and heavy metal contamination. Lead, as one of the most harmful heavy metal contaminants, can execute a significant impact on soil quality and plant growth, depending on its form, as well as its transport and accumulation in soil. This paper describes the source and characteristics of Pb contaminant in soil along a road, and reviews the results of research on remediation of Pb-contaminated soils, aiming at identifying promising approaches to soil remediation along roads.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-12-31

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

  6. CONTAMINANTS AND REMEDIAL OPTIONS AT PESTICIDE SITES

    Science.gov (United States)

    Many types of soils, sediments, and sludges are contaminated with a wide variety of pesticides. ite-specific characteristics such as volume to be treated, extent of contamination, and applicable cleanup goals differ greatly, and contaminant toxicity, migration pathways, persisten...

  7. Comparison of approaches for assessing sustainable remediation of contaminated sites

    DEFF Research Database (Denmark)

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

    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......, while minimizing the indirect cost of remediation to the environment, society and economy. Here we present and compare the available tools and methods for assessing the sustainability of remedial solutions and discuss some of the key issues and future challenges. The aim of a sustainability assessment...

  8. 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

    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......, while minimizing the indirect cost of remediation to the environment, society and economy. Here we present and compare the available tools and methods for assessing the sustainability of remedial solutions and discuss some of the key issues and future challenges. The aim of a sustainability assessment...

  9. The optimisation of electrokinetic remediation for heavy metals and radioactivity contamination on Holyrood-Lunas soil (acrisol species) in Sri Gading Industrial Area, Batu Pahat, Johor, Malaysia.

    Science.gov (United States)

    Mohamed Johar, S; Embong, Z

    2015-11-01

    The optimisation of electrokinetic remediation of an alluvial soil, locally named as Holyrood-Lunas from Sri Gading Industrial Area, Batu Pahat, Johor, Malaysia, had been conducted in this research. This particular soil was chosen due to its relatively high level of background radiation in a range between 139.2 and 539.4 nGy h(-1). As the background radiation is correlated to the amount of parent nuclides, (238)U and (232)Th, hence, a remediation technique, such as electrokinetic, is very useful in reducing these particular concentrations of heavy metal and radionuclides in soils. Several series of electrokinetics experiments were performed in laboratory scale in order to study the influence of certain electrokinetic parameters in soil. The concentration before (pre-electrokinetic) and after the experiment (post-electrokinetic) was determined via X-ray fluorescence (XRF) analysis technique. The best electrokinetic parameter that contributed to the highest achievable concentration removal of heavy metals and radionuclides on each experimental series was incorporated into a final electrokinetic experiment. Here, High Pure Germanium (HPGe) was used for radioactivity elemental analysis. The XRF results suggested that the most optimised electrokinetic parameters for Cr, Ni, Zn, As, Pb, Th and U were 3.0 h, 90 volts, 22.0 cm, plate-shaped electrode by 8 × 8 cm and in 1-D configuration order whereas the selected optimised electrokinetic parameters gave very low reduction of (238)U and (232)Th at 0.23 ± 2.64 and 2.74 ± 23.78 ppm, respectively. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. New Pump and Treat Facility Remedial Action Work Plan for Test Area North (TAN) Final Groundwater Remediation, Operable Unit 1-07B

    Energy Technology Data Exchange (ETDEWEB)

    D. Vandel

    2003-09-01

    This remedial action work plan identifies the approach and requirements for implementing the medical zone remedial action for Test Area North, Operable Unit 1-07B, at the Idaho National Engineering and Environmental Laboratory (INEEL). This plan details management approach for the construction and operation of the New Pump and Treat Facility. As identified in the remedial design/remedial action scope of work, a separate remedial design/remedial action work plan will be prepared for each remedial component of the Operable Unit 1-07B remedial action. This work plan was originally prepared as an early implementation of the final Phase C remediation. At that time, The Phase C implementation strategy was to use this document as the overall Phase C Work Plan and was to be revised to include the remedial actions for the other remedial zones (hotspot and distal zones). After the completion of Record of Decision Amendment: Technical Support Facility Injection Well (TSF-05) and Surrounding Groundwater Contamination (TSF-23) and Miscellaneous No Action Sites, Final Remedial Action, it was determined that each remedial zone would have it own stand-alone remedial action work plan. Revision 1 of this document converts this document to a stand-alone remedial action plan specific to the implementation of the New Pump and Treat Facility used for plume remediation within the medical zone of the OU 1-07B contaminated plume.

  11. Soil Contamination and Remediation Strategies. Current research and future challenge

    Science.gov (United States)

    Petruzzelli, G.

    2012-04-01

    Soil contamination: the heritage of industrial development Contamination is only a part of a whole set of soil degradation processes, but it is one of paramount importance since soil pollution greatly influences the quality of water, food and human health. Soil contamination has been identified as an important issue for action in the European strategy for soil protection, it has been estimated that 3.5 million of sites are potentially contaminated in Europe. Contaminated soils have been essentially discovered in industrial sites landfills and energy production plants, but accumulation of heavy metals and organic compounds can be found also in agricultural land . Remediation strategies. from incineration to bioremediation The assessment of soil contamination is followed by remedial action. The remediation of contaminated soils started using consolidates technologies (incineration inertization etc.) previously employed in waste treatment,. This has contributed to consider a contaminated soil as an hazardous waste. This rough approximation was unfortunately transferred in many legislations and on this basis soil knowledge have been used only marginally in the clean up procedures. For many years soil quality has been identified by a value of concentration of a contaminant and excavation and landfill disposal of soil has been largely used. In the last years the knowledge of remediation technology has rapidly grown, at present many treatment processes appear to be really feasible at field scale, and soil remediation is now based on risk assessment procedures. Innovative technologies, largely dependent on soil properties, such as in situ chemical oxidation, electroremediation, bioventing, soil vapor extraction etc. have been successfully applied. Hazardous organic compounds are commonly treated by biological technologies, biorememdiation and phytoremediation, being the last partially applied also for metals. Technologies selection is no longer exclusively based on

  12. Characteristics, Control and Remediation of Soil Contaminated with Combined Pollution from a Solid Waste Dismantling Area%固废拆解土壤的复合污染特性及其控制与修复

    Institute of Scientific and Technical Information of China (English)

    于红艳; 张昕欣; 杨伟群; 陈红云; 杨雪雪; 朱梦琪

    2012-01-01

    The dismantling of solid waste has resulted in severe contamination of toxic heavy metals, persistant organic pollutant( POPs) , pol-ycyclic aromatic hydrocarbons (PAHs) , polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated diphenyl ethers (PBDEs) for soil in these areas. The methods of control of soil pollutants and remediation of contaminated soil were put forward in the basis of analysis of pollutants environmental behavior in the soil and its migration and transformation laws, which to provide a reliable basis for green dismantling industry and provide reference for remediation of soil contaminated with combined pollution from a solid waste dismantling area.%固废拆解造成了包括重金属、持久性有机污染物(POPs)[多环芳烃(PAHs)、多氯联苯(PCBs)、二噁英(PCDD/Fs)及多溴联苯醚(PBDEs)]的土壤复合污染.探讨了固废拆解土壤的污染源及污染现状,分析了复合污染物在土壤中的环境行为及迁移转化规律,提出了控制土壤污染物对策及污染土壤修复方法,旨在为发展绿色拆解产业提供可靠的依据,为固废拆解导致的土壤污染控制与修复提供参考.

  13. Developing technology of remediation of oil-contaminated soils

    OpenAIRE

    Shevchyk, Lesya; Romaniuk, Olga

    2013-01-01

    Abstract ? The results of developing technologies for cleaning of soils from oil pollution on the example of Boryslav are shown. The prospects of tree species for the remediation of oil-contaminated soils are studied. The best results of cleaning oil contaminated soils with the application of Hippophae rhamnoides L. plants were obtained. It is a promising measure for restoring the oil-contaminated soils, attractive both from environmental and economical point of view.

  14. Effect of Sludge Amendment on Remediation of Metal Contaminated Soils

    Directory of Open Access Journals (Sweden)

    Andrés Navarro

    2012-11-01

    Full Text Available Column-leaching and pilot-scale experiments were conducted to evaluate the use of biosolids (sewage sludges to control the mobilization of metals from contaminated soils with smelting slags. The pilot-scale experiments using amended soils showed that Cu, Pb and Sb were retained, decreasing their concentrations from 250 mg/L, 80 mg/L and 6 mg/L, respectively in the leachates of contaminated soils, to <20 mg/L, 40 mg/L and 4 mg/L, respectively, in the amended material. Hydrogeochemical modeling of the leachates using Minteq revealed that the degree of complexation of Cu rose 56.3% and 57.6% in leachates of amended soils. Moreover, Cu may be immobilized by biosolids, possibly via adsorption by oxyhydroxides of Fe or sorption by organic matter. The partial retention of Pb coincides with the possible precipitation of chloropyromorphite, which is the most stable mineral phase in the pH-Eh conditions of the leachates from the amended material. The retention of Sb may be associated with the precipitation of Sb2O3, which is the most stable mineral phase in the experimental conditions. The organic amendments used in this study increased some metal and metalloid concentrations in the leachates (Fe, Mn, Ni, As and Se, which suggests that the organic amendments could be used with caution to remediate metal contaminated areas.

  15. Ecological effects of contaminants and remedial actions in Bear Creek

    Energy Technology Data Exchange (ETDEWEB)

    Southworth, G.R.; Loar, J.M.; Ryon, M.G.; Smith, J.G.; Stewart, A.J. (Oak Ridge National Lab., TN (United States)); Burris, J.A. (C. E. Environmental, Inc., Tallahassee, FL (United States))

    1992-01-01

    Ecological studies of the Bear Creek watershed, which drains the area surrounding several Oak Ridge Y-12 Plant waste disposal facilities, were initiated in May 1984 and are continuing at present. These studies consisted of an initial, detailed characterization of the benthic invertebrate and fish communities in Bear Creek, and they were followed by a presently ongoing monitoring phase that involves reduced sampling intensities. The characterization phase utilized two approaches: (1) instream sampling of benthic invertebrate and fish communities in Bear Creek to identify spatial and temporal patterns in distribution and abundance and (2) laboratory bioassays on water samples from Bear Creek and selected tributaries to identify potential sources of toxicity to biota. The monitoring phase of the ecological program relates to the long-term goals of identifying and prioritizing contaminant sources and assessing the effectiveness of remedial actions. It continues activities of the characterization phase at less frequent intervals. The Bear Greek Valley is a watershed that drains the area surrounding several closed Oak Ridge Y-12 Plant waste disposal facilities. Past waste disposal practices in Bear Creek Valley resulted in contamination of Bear Creek and consequent ecological damage. Extensive remedial actions have been proposed at waste sites, and some of the have been implemented or are now underway. The proposed study plan consists of an initial, detailed characterization of the benthic invertebrate and fish communities in Bear Creek in the first year followed by a reduction in sampling intensity during the monitoring phase of the plan. The results of sampling conducted from May 1984 through early 1989 are presented in this report.

  16. Electro kinetic remediation of contaminated habitats | Shenbagavalli ...

    African Journals Online (AJOL)

    African Journal of Environmental Science and Technology ... which move the aqueous phase contaminants in the subsurface from one electrode to the other. ... or contaminants desorbed from the soil surface are transported towards ... in the field successfully, the different geochemical interactions that occur in the field soils ...

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

    Energy Technology Data Exchange (ETDEWEB)

    Nesbitt, Victoria A [Nuvia Limited, The Library, Didcot, Oxfordshire, OX11 0RL (United Kingdom)

    2013-07-01

    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

  18. Regionally contaminated aquifers--toxicological relevance and remediation options (Bitterfeld case study).

    Science.gov (United States)

    Heidrich, Susanne; Schirmer, Mario; Weiss, Holger; Wycisk, Peter; Grossmann, Jochen; Kaschl, Arno

    2004-12-15

    Large-scale contaminated megasites like Bitterfeld in eastern Germany are characterized by a regional contamination of soil, surface water and groundwater as a result of a long and varied history of chemical production. While the contaminants in soils and sediments mostly represent a localized problem, pollutants in groundwater may spread to uncontaminated areas and endanger receptors like surface water and drinking water wells according to the site-specific hydrologic regime. From the toxicological point of view, the contaminants at the Bitterfeld megasite represent a dangerous cocktail of various harmful substances coming from a multitude of sources. Appropriate remediation techniques must be able to remedy the specific problems arising from hot spot areas within the megasite in addition to preventing a further extension of the contaminated zone towards uncontaminated compartments. Therefore, a combination of specifically designed remediation technologies based on the pump and treat-principle with in situ technologies, such as reactive walls and monitored/enhanced natural attenuation, is necessary to efficiently address the miscellaneous challenges at this megasite. In this paper, the currently known contaminant distribution, the associated problems for human health and the environment and possible remediation strategies are presented for the Bitterfeld megasite.

  19. A Review of Centrifugal Testing of Gasoline Contamination and Remediation

    OpenAIRE

    Jay N. Meegoda; Liming Hu

    2011-01-01

    Leaking underground storage tanks (USTs) containing gasoline represent a significant public health hazard. Virtually undetectable to the UST owner, gasoline leaks can contaminate groundwater supplies. In order to develop remediation plans one must know the extent of gasoline contamination. Centrifugal simulations showed that in silty and sandy soils gasoline moved due to the physical process of advection and was retained as a pool of free products above the water table. However, in clayey soi...

  20. Processes affecting the remediation of chromium-contaminated sites.

    OpenAIRE

    Palmer, C.D.; Wittbrodt, P R

    1991-01-01

    The remediation of chromium-contaminated sites requires knowledge of the processes that control the migration and transformation of chromium. Advection, dispersion, and diffusion are physical processes affecting the rate at which contaminants can migrate in the subsurface. Heterogeneity is an important factor that affects the contribution of each of these mechanisms to the migration of chromium-laden waters. Redox reactions, chemical speciation, adsorption/desorption phenomena, and precipitat...

  1. Environmental impacts of remediation of a trichloroethene-contaminated site: life cycle assessment of remediation alternatives.

    Science.gov (United States)

    Lemming, Gitte; Hauschild, Michael Z; Chambon, Julie; Binning, Philip J; Bulle, Cécile; Margni, Manuele; Bjerg, Poul L

    2010-12-01

    The environmental impacts of remediation of a chloroethene-contaminated site were evaluated using life cycle assessment (LCA). The compared remediation options are (i) in situ bioremediation by enhanced reductive dechlorination (ERD), (ii) in situ thermal desorption (ISTD), and (iii) excavation of the contaminated soil followed by off-site treatment and disposal. The results showed that choosing the ERD option will reduce the life-cycle impacts of remediation remarkably compared to choosing either ISTD or excavation, which are more energy-demanding. In addition to the secondary impacts of remediation, this study includes assessment of local toxic impacts (the primary impact) related to the on-site contaminant leaching to groundwater and subsequent human exposure via drinking water. The primary human toxic impacts were high for ERD due to the formation and leaching of chlorinated degradation products, especially vinyl chloride during remediation. However, the secondary human toxic impacts of ISTD and excavation are likely to be even higher, particularly due to upstream impacts from steel production. The newly launched model, USEtox, was applied for characterization of primary and secondary toxic impacts and combined with a site-dependent fate model of the leaching of chlorinated ethenes from the fractured clay till site.

  2. Radioactive tank waste remediation focus area

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    EM`s Office of Science and Technology has established the Tank Focus Area (TFA) to manage and carry out an integrated national program of technology development for tank waste remediation. The TFA is responsible for the development, testing, evaluation, and deployment of remediation technologies within a system architecture to characterize, retrieve, treat, concentrate, and dispose of radioactive waste stored in the underground stabilize and close the tanks. The goal is to provide safe and cost-effective solutions that are acceptable to both the public and regulators. Within the DOE complex, 335 underground storage tanks have been used to process and store radioactive and chemical mixed waste generated from weapon materials production and manufacturing. Collectively, thes tanks hold over 90 million gallons of high-level and low-level radioactive liquid waste in sludge, saltcake, and as supernate and vapor. Very little has been treated and/or disposed or in final form.

  3. Assessment and Remediation of Lead Contamination in Esperance, Western Australia

    Directory of Open Access Journals (Sweden)

    McCafferty P. B.

    2013-04-01

    Full Text Available This paper presents an overview of a lead contamination event that occurred over a period of time in and around Esperance, Western Australia. It also describes the scientific developments necessary to effect the large scale cleanup of lead contamination in the town. This work was possibly the largest environmental cleanup of its kind ever undertaken in Australia. The work undertaken involved characterisation and assessment of the extent of contamination, development of remediation techniques and validation procedures to ensure that that this cleaning had been successful.

  4. 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

  5. Identification of 300 Area Contaminants of Potential Concern for Soil

    Energy Technology Data Exchange (ETDEWEB)

    R.W. Ovink

    2010-04-05

    This report documents the process used to identify source area contaminants of potential concern (COPCs) in support of the 300 Area remedial investigation/feasibility study (RI/FS) work plan. This report also establishes the exclusion criteria applicable for 300 Area use and the analytical methods needed to analyze the COPCs.

  6. Remediation alternatives for low-level herbicide contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Conger, R.M. [BASF Corp., Geismar, LA (United States)

    1995-10-01

    In early 1995, an evaluation of alternatives for remediation of a shallow groundwater plume containing low-levels of an organic herbicide was conducted at BASF Corporation, a petrochemical facility located in Ascension Parish, Louisiana. The contaminated site is located on an undeveloped portion of property within 1/4 mile of the east bank of the Mississippi River near the community of Geismar. Environmental assessment data indicated that about two acres of the thirty acre site had been contaminated from past waste management practices with the herbicide bentazon. Shallow soils and groundwater between 5 to 15 feet in depth were affected. Maximum concentrations of bentazon in groundwater were less than seven parts per million. To identify potentially feasible remediation alternatives, the environmental assessment data, available research, and cost effectiveness were reviewed. After consideration of a preliminary list of alternatives, only two potentially feasible alternatives could be identified. Groundwater pumping, the most commonly used remediation alternative, followed by carbon adsorption treatment was identified as was a new innovative alternative known as vegetative transpiration. This alternative relies on the natural transpiration processes of vegetation to bioremediate organic contaminants. Advantages identified during screening suggest that the transpiration method could be the best remediation alternative to address both economic and environmental factors. An experiment to test critical factors of the vegetatived transpiration alternative with bentazon was recommended before a final decision on feasibility can be made.

  7. Microemulsion-enhanced remediation of soils contaminated with organochlorine pesticides.

    Science.gov (United States)

    Zhang, Yanlin; Wong, Jonathan W C; Zhao, Zhenyong; Selvam, Ammaiyappan

    2011-12-01

    Soil contaminated by organic pollutants, especially chlorinated aromatic compounds such as DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane), is an environmental concern because of the strong sorption of organochlorine pesticide onto the soil matrix and persistence in the environment. The remediation of organochlorine pesticide contaminated soils through microemulsion is an innovative technology to expedite this process. The remediation efficiency was evaluated by batch experiments through studying the desorption of DDT and hexachlorocyclohexane (y-HCH) and sorption of microemulsion composed of Triton X-100, 1-pentanol and linseed oil in the soil-surfactant-water suspension system. The reduction of desorption efficiency caused by the sorption loss of microemulsion components onto the soil could be corrected by the appropriate adjustment of C/S (Cosurfactant/Surfactant) and O/S (Oil/Surfactant) ratio. The C/S and O/S ratios of 1:2 and 3:20 were suitable to desorb DDT and gamma-HCH from the studied soils because of the lower sorption of Triton X-100 onto the soil. Inorganic salts added in microemulsion increased the pesticides desorption efficiency of pesticides and calcium chloride has a stronger ability to enhance the desorption of DDT than sodium chloride. From the remediation perspective, the balance of surfactant or cosurfactant sorbed to soil and desorption efficiency should be taken into consideration to enhance the remediation of soils contaminated by organochlorine pesticides.

  8. Geological characterization of contaminated sites in urban areas (Denmark)

    DEFF Research Database (Denmark)

    Andersen, Theis Raaschou; Nissen, Randi Warncke; Poulsen, Søren Erbs

    2015-01-01

    In Denmark, contaminations from industry and farming represent a significant threat to groundwater resources. Hence there is a focus on identifying and locating these contaminated places. Once located, contaminations are mapped and monitored and remediation efforts are undertaken. Remediation is ...

  9. Remediation of PCB contaminated soils in the Canadian Arctic: excavation and surface PRB technology.

    Science.gov (United States)

    Kalinovich, Indra; Rutter, Allison; Poland, John S; Cairns, Graham; Rowe, R Kerry

    2008-12-15

    The site BAF-5 is located on the summit of Resolution Island, Nunavut, just southeast of Baffin Island at 61 degrees 35'N and 60 degrees 40'W. The site was part of a North American military defense system established in the 1950s that became heavily contaminated with PCBs during and subsequent, its operational years. Remediation through excavation of the PCB contaminated soil at Resolution Island began in 1999 and at its completion in 2006 approximately 5 tonnes of pure PCBs in approximately 20,000 m3 of soil were remediated. Remediation strategies were based on both quantity of soil and level of contamination in the soil. Excavation removed 96% of the PCB contaminated soil on site. In 2003, a surface funnel-and-gate permeable reactive barrier was design and constructed to treat the remaining contamination left in rock crevices and inaccessible areas of the site. Excavation had destabilized contaminated soil in the area, enabling contaminant migration through erosion and runoff pathways. The barrier was designed to maximize sedimentation through settling ponds. This bulk removal enabled the treatment of highly contaminated fines and water through a permeable gate. The increased sediment loading during excavation required both modifications to the funnel and a shift to a more permeable, granular system. Granulated activated charcoal was chosen for its ability to both act as a particle retention filter and adsorptive filter. The reduction in mass of PCB and volume of soils trapped by the funnel of the barrier indicate that soils are re-stabilizing. In 2007, nonwoven geotextiles were re-introduced back into the filtration system as fine filtering could be achieved without clogging. Monitoring sites downstream indicate that the barrier system is effective. This paper describes the field progress of PCB remediation at Resolution Island.

  10. Remediation of plutonium-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Amos, S.; Coudace, I.; Voss, J

    2005-07-15

    The effectiveness of paramagnetic separation to remove plutonium from soils from the Aldermaston (UK) site has been investigated and reported to the commissioners of the project, AWE plc, and also subsequently at the WM'05 Conference (Tucson, AZ). The results showed that plutonium can be effectively concentrated in soils using magnetic separation and size fractionation. The work also investigated other methods to enhance the separation process. These approaches were: the use of sodium hexametaphosphate (ca. 1% by weight soil) to disperse the clay minerals; roasting to remove organic matter and to oxidise any organically-compIexed plutonium; ultrasonic vibration to break physical bonds between any plutonium oxide and soil particles; leaching of the <75mm fractions with selected reagents to extract plutonium. As a result of this work, engineering concepts are being developed which will enable more than 95% of some of the AWE contaminated soils to be rated for free release. (author)

  11. Remediation of TCE-contaminated groundwater using nanocatalyst and bacteria.

    Science.gov (United States)

    Kang, Ser Ku; Seo, Hyunhee; Sun, Eunyoung; Kim, Inseon; Roh, Yul

    2011-08-01

    The objective of this study was to develop and evaluate the remediation of trichloroethene (TCE)-contaminated groundwater using both a nanocatalyst (bio-Zn-magnetite) and bacterium (similar to Clostridium quinii) in anoxic environments. Of the 7 nanocatalysts tested, bio-Zn-magnetite showed the highest TCE dechlorination efficiency, with an average of ca. 90% within 8 days in a batch experiment. The column tests confirmed that the application of bio-Zn-magnetite in combination with the bacterium achieved high degradation efficiency (ca. 90%) of TCE within 5 days compared to the nanocatalyst only, which degraded only 30% of the TCE. These results suggest that the application of a nanocatalyst and the bacterium have potential for the remediation of TCE-contaminated groundwater in subsurface environments.

  12. Remediation of contaminated soil using soil washing-a review

    Directory of Open Access Journals (Sweden)

    N.Karthika

    2016-01-01

    Full Text Available Pb, Zn, Ni, Cu, Mn and Cd are heavy metals occur naturally as trace elements in many soils. The present paper reviews the remediation of heavy metals of contaminated soil by soil washing using different agents. It was noted that the contact time, pH, concentration of extract ant and agitation speed were affected the process while remediation, so accordingly select the conditions to obtain efficiency which is mainly depend upon the type of soil, contaminationtype, contamination period and metals present in it.EDTA is effective when compared with other chelating agents for heavy metals especially for lead but it has low biodegradation. Because of the nature of low biodegradability, EDTA can be reusedfurther by membrane separation and electrochemical treatment, or degraded by advanced oxidation processes.

  13. Considering bioavailability in the remediation of heavy metal contaminated sites

    Directory of Open Access Journals (Sweden)

    Leita L.

    2013-04-01

    Full Text Available Many years of research have demonstrated that instead of the total concentration of metals in soil, bioavailability is the key to understand the environmental risk derived by metals, since adverse effects are related only to the biologically available forms of these elements. The knowledge of bioavailability can decrease the uncertainties in evaluating exposure in human and ecological risk assessment. At the same time, the efficiency of remediation treatments could be greatly influenced by availability of the contaminants. Consideration of the bioavailability processes at contaminated sites could be useful in site-specific risk assessment: the fraction of mobile metals, instead of total content should be provided as estimates of metal exposure. Moreover, knowledge of the chemical forms of heavy metals in soils is a critical component in the evaluation of applicability of different remediation technologies such as phytoremdiation or soil washing.

  14. Feasibility study on the use of soil washing to remediate the As-Hg contamination at an ancient mining and metallurgy area.

    Science.gov (United States)

    Sierra, C; Menéndez-Aguado, J M; Afif, E; Carrero, M; Gallego, J R

    2011-11-30

    Soils in abandoned mining sites generally present high concentrations of trace elements, such as As and Hg. Here we assessed the feasibility of washing procedures to physically separate these toxic elements from soils affected by a considerable amount of mining and metallurgical waste ("La Soterraña", Asturias, NW Spain). After exhaustive soil sampling and subsequent particle-size separation via wet sieving, chemical and mineralogical analysis revealed that the finer fractions held very high concentrations of As (up to 32,500 ppm) and Hg (up to 1600 ppm). These elements were both associated mainly with Fe/Mn oxides and hydroxides. Textural and geochemical data were correlated with the geological substrate by means of a multivariate statistical analysis. In addition, the Hg liberation size (below 200 μm) was determined to be main factor conditioning the selection of suitable soil washing strategies. These studies were finally complemented with a specific-gravity study performed with a C800 Mozley separator together with a grindability test, both novel approaches in soil washing feasibility studies. The results highlighted the difficulties in treating "La Soterraña" soils. These difficulties are attributed to the presence of contaminants embedded in the soil and spoil heap aggregates, caused by the meteorization of gangue and ore minerals. As a result of these two characteristics, high concentrations of the contaminants accumulate in all grain-size fractions. Therefore, the soil washing approach proposed here includes the grinding of particles above 125 μm.

  15. Remediation of Oil-Contaminated Soil in Greenland

    OpenAIRE

    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 and N:P:K), stabilizer (crab shells) and heating (20°C). In this work a clear reduction in hydrocarbon content was observed during the treatment period of 730 days. No significant difference in degrad...

  16. Remediation of Diesel Fuel Contaminated Sandy Soil using Ultrasonic Waves

    Directory of Open Access Journals (Sweden)

    Wulandari P.S.

    2010-01-01

    Full Text Available Ultrasonic cleaning has been used in industry for some time, but the application of ultrasonic cleaning in contaminated soil is just recently received considerable attention, it is a very new technique, especially in Indonesia. An ultrasonic cleaner works mostly by energy released from the collapse of millions of microscopic cavitations near the dirty surface. This paper investigates the use of ultrasonic wave to enhance remediation of diesel fuel contaminated sandy soil considering the ultrasonic power, soil particle size, soil density, water flow rate, and duration of ultrasonic waves application.

  17. Contaminant remediation decision analysis using information gap theory

    CERN Document Server

    Harp, Dylan R

    2011-01-01

    Decision making under severe lack of information is a ubiquitous situation in nearly every applied field of engineering, policy, and science. A severe lack of information precludes our ability to determine a frequency of occurrence of events or conditions that impact the decision; therefore, decision uncertainties due to a severe lack of information cannot be characterized probabilistically. To circumvent this problem, information gap (info-gap) theory has been developed to explicitly recognize and quantify the implications of information gaps in decision making. This paper presents a decision analysis based on info-gap theory developed for a contaminant remediation scenario. The analysis provides decision support in determining the fraction of contaminant mass to remove from the environment in the presence of a lack of information related to the contaminant mass flux into an aquifer. An info-gap uncertainty model is developed to characterize uncertainty due to a lack of information concerning the contaminant...

  18. Subsurface Contamination Focus Area technical requirements. Volume 1: Requirements summary

    Energy Technology Data Exchange (ETDEWEB)

    Nickelson, D.; Nonte, J.; Richardson, J.

    1996-10-01

    This document summarizes functions and requirements for remediation of source term and plume sites identified by the Subsurface Contamination Focus Area. Included are detailed requirements and supporting information for source term and plume containment, stabilization, retrieval, and selective retrieval remedial activities. This information will be useful both to the decision-makers within the Subsurface Contamination Focus Area (SCFA) and to the technology providers who are developing and demonstrating technologies and systems. Requirements are often expressed as graphs or charts, which reflect the site-specific nature of the functions that must be performed. Many of the tradeoff studies associated with cost savings are identified in the text.

  19. Fire in a contaminated area

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, G.W., Westinghouse Hanford

    1996-08-08

    This document supports the development and presentation of the following accident scenario in the TWRS Final Safety Analysis Report: Fire in Contaminated Area. The calculations needed to quantify the risk associated with this accident scenario are included within.

  20. CMI Remedy Selection for HE- and Barium-Contaminated Vadose Zone and Alluvium at LANL

    Science.gov (United States)

    Hickmott, D.; Reid, K.; Pietz, J.; Ware, D.

    2008-12-01

    A high explosives (HE) machining building outfall at Los Alamos National Laboratory's Technical Area 16 discharged millions of gallons of HE- and barium-contaminated water into the Canon de Valle watershed. The effluent contaminated surface soils, the alluvial aquifer, vadose zone waters, and deep-perched and regional groundwaters with HE and barium, frequently at levels greater than regulatory standards. Site characterization studies began in 1995 and included extensive monitoring of surface water, groundwater, soils, and subsurface solid media. Hydrogeologic and geophysical studies were conducted to help understand contaminant transport mechanisms and pathways. Results from the characterization studies were used to develop a site conceptual model. In 2000 the principal source area was removed. The ongoing Corrective Measure Study (CMS) and Corrective Measure Implementation (CMI) focus on residual vadose zone contamination and on the contaminated alluvial system. Regulators recently selected a CMI remedy that combined: 1) augmented source removal; 2) grouting of an HE- contaminated surge bed; 3) deployment of Stormwater Management System (SMS) stormfilters in contaminated springs; and 4) permeable reactive barriers (PRBs) in contaminated alluvium. The hydrogeologic conceptual model for the vadose zone and alluvial system as well as the status of the canyon as habitat for the Mexican Spotted Owl were key factors in selection of these minimal-environmental-impact remedies. The heterogeneous vadose zone, characterized by flow and contaminant transport in fractures and in surge beds, requires contaminant treatment at a point of discharge. The canyon PRB is being installed to capture water and contaminants prior to infiltration into the vadose zone. Pilot-scale testing of the SMS and lab-scale batch and column tests of a range of media suggest that granular activated carbon, zeolite, and gypsum may be effective media for removal of HE and/or barium from contaminated

  1. A Review of Centrifugal Testing of Gasoline Contamination and Remediation

    Directory of Open Access Journals (Sweden)

    Jay N. Meegoda

    2011-08-01

    Full Text Available Leaking underground storage tanks (USTs containing gasoline represent a significant public health hazard. Virtually undetectable to the UST owner, gasoline leaks can contaminate groundwater supplies. In order to develop remediation plans one must know the extent of gasoline contamination. Centrifugal simulations showed that in silty and sandy soils gasoline moved due to the physical process of advection and was retained as a pool of free products above the water table. However, in clayey soils there was a limited leak with lateral spreading and without pooling of free products above the water table. Amount leaked depends on both the type of soil underneath the USTs and the amount of corrosion. The soil vapor extraction (SVE technology seems to be an effective method to remove contaminants from above the water table in contaminated sites. In-situ air sparging (IAS is a groundwater remediation technology for contamination below the water table, which involves the injection of air under pressure into a well installed into the saturated zone. However, current state of the art is not adequate to develop a design guide for site implementation. New information is being currently generated by both centrifugal tests as well as theoretical models to develop a design guide for IAS. The petroleum contaminated soils excavated from leaking UST sites can be used for construction of highway pavements, specifically as sub-base material or blended and used as hot or cold mix asphalt concrete. Cost analysis shows that 5% petroleum contaminated soils is included in hot or cold mix asphalt concrete can save US$5.00 production cost per ton of asphalt produced.

  2. ENGINEERING BULLETIN: SEPARATION/CONCENTRATION TECHNOLOGY ALTERNATIVES FOR THE REMEDIATION OF PESTICIDE-CONTAMINATED SOIL

    Science.gov (United States)

    Pesticide contamination includes a wide variety of compounds and may result from manufacturing improper storage, handling, disposal; or agricultural processes. It can occur in soil and can lead to secondary contamination of groundwater. Remediation of pesticide-contaminated soils...

  3. Bioventing remediation and ecotoxicity evaluation of phenanthrene-contaminated soil.

    Science.gov (United States)

    García Frutos, F Javier; Escolano, Olga; García, Susana; Babín, Mar; Fernández, M Dolores

    2010-11-15

    The objectives of soil remediation processes are usually based on threshold levels of soil contaminants. However, during remediation processes, changes in bioavailability and metabolite production can occur, making it necessary to incorporate an ecotoxicity assessment to estimate the risk to ecological receptors. The evolution of contaminants and soil ecotoxicity of artificially phenanthrene-contaminated soil (1000 mg/kg soil) during soil treatment through bioventing was studied in this work. Bioventing was performed in glass columns containing 5.5 kg of phenanthrene-contaminated soil and uncontaminated natural soil over a period of 7 months. Optimum conditions of mineralisation (humidity=60% WHC; C/N/P=100:20:1) were determined in a previous work. The evolution of oxygen consumption, carbon dioxide production, phenanthrene concentration and soil toxicity were studied on sacrificed columns at periods of 0, 3 and 7 months. Toxicity to soil and aquatic organisms was determined using a multispecies system in the soil columns (MS-3). In the optimal bioventing treatability test, we obtained a reduction rate in phenanthrene concentration higher that 93% after 7 months of treatment. The residual toxicity obtained at the end of the treatment was not attributed to the low phenanthrene concentration, but to the ammonia used to restore the optimal C/N ratio.

  4. Testing amendments for remediation of military range contaminated soil.

    Science.gov (United States)

    Siebielec, Grzegorz; Chaney, Rufus L

    2012-10-15

    Military range soils are often strongly contaminated with metals. Information on the effectiveness of remediation of these soils is scarce. We tested the effectiveness of compost and mineral treatments for remediation and revegetation of military range soil collected in Aberdeen, MD. The soil was barren due to zinc (Zn) phytotoxicity while lead (Pb) posed a substantial risk to soil biota, wildlife and humans through various pathways. Seven treatments were tested: untreated control, agricultural NPK fertilization, high phosphate fertilization plus agricultural rates of NK, CaCO(3), "Orgro" biosolid compost, "Orgro" + CaCO(3), "Orgro" + CaCO(3) + Mn sulfate. All compost treatments alleviated Zn phytotoxicity to tall fescue; however compost combined with liming reduced plant Zn content up to 158-162 mg kg(-1). Compost added with lime reduced Pb in-vitro bioaccessibility from 32.5 to 20.4% of total Pb and was the most effective among the tested treatments. The study revealed the effectiveness of biosolids compost and lime mixture in the rapid stabilization of metals and revegetation of military range contaminated soils. The persistence of the remediation needs to be, however, confirmed in the long-term field study.

  5. Characterization and remediation of soils contaminated with uranium.

    Science.gov (United States)

    Gavrilescu, Maria; Pavel, Lucian Vasile; Cretescu, Igor

    2009-04-30

    Environmental contamination caused by radionuclides, in particular by uranium and its decay products is a serious problem worldwide. The development of nuclear science and technology has led to increasing nuclear waste containing uranium being released and disposed in the environment. The objective of this paper is to develop a better understanding of the techniques for the remediation of soils polluted with radionuclides (uranium in particular), considering: the chemical forms of uranium, including depleted uranium (DU) in soil and other environmental media, their characteristics and concentrations, and some of the effects on environmental and human health; research issues concerning the remediation process, the benefits and results; a better understanding of the range of uses and situations for which each is most appropriate. The paper addresses the main features of the following techniques for uranium remediation: natural attenuation, physical methods, chemical processes (chemical extraction methods from contaminated soils assisted by various suitable chelators (sodium bicarbonate, citric acid, two-stage acid leaching procedure), extraction using supercritical fluids such as solvents, permeable reactive barriers), biological processes (biomineralization and microbial reduction, phytoremediation, biosorption), and electrokinetic methods. In addition, factors affecting uranium removal from soils are furthermore reviewed including soil characteristics, pH and reagent concentration, retention time.

  6. Resuspension of sediment, a new approach for remediation of contaminated sediment.

    Science.gov (United States)

    Pourabadehei, Mehdi; Mulligan, Catherine N

    2016-06-01

    Natural events and anthropogenic activities are the reasons of undesirable resuspension of contaminated sediments in aquatic environment. Uncontrolled resuspension could remobilize weakly bound heavy metals into overlying water and pose a potential risk to aquatic ecosystem. Shallow harbours, with contaminated sediments are subjected to the risk of uncontrolled resuspension. Remediation of sediments in these areas cannot be performed by conventional in situ methods (e.g. capping with or without reactive amendment). Ex situ remediation also requires dredging of sediment, which could increase the risk of spreading contaminants. Alternatively, the resuspension technique was introduced to address these issues. The concept of the resuspension method is that finer sediments have a greater tendency to adsorb the contamination. Therefore, finer sediments, believed carry more concentration of contaminants, were targeted for removal from aquatic environment by a suspension mechanism in a confined water column. The objective of this study was to evaluate the feasibility of the resuspension technique as a new approach for remediation of contaminated sediment and a viable option to reduce the risk of remobilization of contaminants in harbours due to an undesirable resuspension event. Unlike the common in situ techniques, the resuspension method could successfully reduce the total concentration of contaminants in almost all samples below the probable effect level (PEL) with no significant change in the quality of overlying water. The results indicated that removal efficiency could be drastically enhanced for metals in sediment with a higher enrichment factor. Moreover, availability of metals (e.g. Cd and Pb) with a high concentration in labile fractions was higher in finer sediments with a high enrichment factor. Consequently, removal of contaminants from sediment through the resuspension method could reduce the risk of mobility and availability of metals under changing

  7. Enhancement of in situ Remediation of Hydrocarbon Contaminated Soil

    Energy Technology Data Exchange (ETDEWEB)

    Palmroth, M.

    2006-07-01

    Approximately 750 000 sites of contaminated land exist across Europe. The harmful chemicals found in Finnish soils include heavy metals, oil products, polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), chlorophenols, and pesticides. Petroleum and petroleum products enter soil from ruptured oil pipelines, land disposal of refinery products, leaking storage tanks and through accidents. PAH contamination is caused by the spills of coal tar and creosote from coal gasification and wood treatment sites in addition to oil spills. Cleanup of soil by bioremediation is cheaper than by chemical and physical processes. However, the cleaning capacity of natural attenuation and in situ bioremediation is limited. The purpose of this thesis was to find feasible options to enhance in situ remediation of hydrocarbon contaminants. The aims were to increase the bioavailability of the contaminants and microbial activity at the subsurface in order to achieve higher contaminant removal efficiency than by intrinsic biodegradation alone. Enhancement of microbial activity and decrease of soil toxicity during remediation were estimated by using several biological assays. The performance of these assays was compared in order to find suitable indicators to follow the progress of remediation. Phytoremediation and chemical oxidation are promising in situ techniques to increase the degradation of hydrocarbons in soil. Phytoremediation is plant-enhanced decontamination of soil and water. Degradation of hydrocarbons is enhanced in the root zone by increased microbial activity and through the detoxifying enzymes of plants themselves. Chemical oxidation of contaminants by Fenton's reaction can produce degradation products which are more biodegradable than the parent compounds. Fenton's reaction and its modifications apply solutions of hydrogen peroxide and iron for the oxidation of organic chemicals. The cost of oxidation can be reduced by aiming at partial instead of full

  8. 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....... The degradation proceeded further at the elevated temperature and even more when heat and nutrients were combined. In the second work, a nutrient rich soil highly polluted by weathered heavy oil was aerated by insertion of air-channels, and heated to 20°C. Between 19 % and 34 % of the oil pollution was removed...

  9. Stabilization/Solidification Remediation Method for Contaminated Soil: A Review

    Science.gov (United States)

    Tajudin, S. A. A.; Azmi, M. A. M.; Nabila, A. T. A.

    2016-07-01

    Stabilization/Solidification (S/S) is typically a process that involves a mixing of waste with binders to reduce the volume of contaminant leachability by means of physical and chemical characteristics to convert waste in the environment that goes to landfill or others possibly channels. Stabilization is attempts to reduce the solubility or chemical reactivity of the waste by changing the physical and chemical properties. While, solidification attempt to convert the waste into easily handled solids with low hazardous level. These two processes are often discussed together since they have a similar purpose of improvement than containment of potential pollutants in treated wastes. The primary objective of this review is to investigate the materials used as a binder in Stabilization/Solidification (S/S) method as well as the ability of these binders to remediate the contaminated soils especially by heavy metals.

  10. In Situ Remediation of {sup 137}Cs Contaminated Wetlands Using Naturally Occurring Minerals

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, D.I.

    1999-08-11

    Cesium-137 has contaminated a large area of the wetlands on the Savannah River Site. Remediation of the contaminated wetlands is problematic because current techniques destroy the sensitive ecosystem and generate a higher dose to workers. To address this problem, we proposed a non-trusive, in situ technology to sequester 137Cs in sediments. One intention of this study was to provide information regarding a go/no go decision for future work. Since the proof-of-concept was successful and several minerals were identified as potential candidates for this technology, a go decision was made.

  11. THE SCENARIOS APPROACH TO ATTENUATION-BASED REMEDIES FOR INORGANIC AND RADIONUCLIDE CONTAMINANTS

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K.; Rysz, M.; Truex, M.; Brady, P.; Newell, C.; Denham, M.

    2011-08-04

    Guidance materials based on use of conceptual model scenarios were developed to assist evaluation and implementation of attenuation-based remedies for groundwater and vadose zones contaminated with inorganic and radionuclide contaminants. The Scenarios approach is intended to complement the comprehensive information provided in the US EPA's Technical Protocol for Monitored Natural Attenuation (MNA) of Inorganic Contaminants by providing additional information on site conceptual models and extending the evaluation to consideration of Enhanced Attenuation approaches. The conceptual models incorporate the notion of reactive facies, defined as units with hydrogeochemical properties that are different from surrounding units and that react with contaminants in distinct ways. The conceptual models also incorporate consideration of biogeochemical gradients, defined as boundaries between different geochemical conditions that have been induced by waste disposal or other natural phenomena. Gradients can change over time when geochemical conditions from one area migrate into another, potentially affecting contaminant mobility. A recognition of gradients allows the attenuation-affecting conditions of a site to be projected into the future. The Scenarios approach provides a stepwise process to identify an appropriate category of conceptual model and refine it for a specific site. Scenario materials provide links to pertinent sections in the EPA technical protocol and present information about contaminant mobility and important controlling mechanism for attenuation-based remedies based on the categories of conceptual models.

  12. Natural Attenuation Software (NAS): A computer program for estimating remediation times of contaminated groundwater

    Science.gov (United States)

    Mendez, E.; Widdowson, M.; Brauner, S.; Chapelle, F.; Casey, C.; ,

    2004-01-01

    This paper describes the development and application of a modeling system called Natural Attenuation Software (NAS). NAS was designed as a screening tool to estimate times of remediation (TORs), associated with monitored natural attenuation (MNA), to lower groundwater contaminant concentrations to regulatory limits. Natural attenuation processes that NAS models include advection, dispersion, sorption, biodegradation, and non-aqueous phase liquid (NAPL) dissolution. This paper discusses the three main interactive components of NAS: 1) estimation of the target source concentration required for a plume extent to contract to regulatory limits, 2) estimation of the time required for NAFL contaminants in the source area to attenuate to a predetermined target source concentration, and 3) estimation of the time required for a plume extent to contract to regulatory limits after source reduction. The model's capability is illustrated by results from a case study at a MNA site, where NAS time of remediation estimates compared well with observed monitoring data over multiple years.

  13. Evaluation of surfactant flushing for remediating EDC-tar contamination

    Science.gov (United States)

    Liang, Chenju; Hsieh, Cheng-Lin

    2015-06-01

    Ethylene dichloride tar (EDC-tar) is a dense non-aqueous phase liquid (DNAPL) waste originated from the process of vinyl chloride production, with major constituents including chlorinated aliphatic and aromatic hydrocarbons. This study investigated the feasibility of Surfactant Enhanced Aquifer Remediation (SEAR) for treating EDC-tar contaminated aquifers. Initial experiments explored the potential to enhance the apparent solubility of EDC-tar using single or mixed surfactants. The results showed that an aqueous solution mixed anionic and non-ionic surfactants (i.e., SDS/Tween 80) exhibited higher EDC-tar apparent solubility and lower surface tension than other surfactant systems tested. Additionally, alkaline pH aids in increasing the EDC-tar apparent solubility. In column flushing experiments, it was seen that the alkaline mixed SDS/Tween 80 solution showed better removal of pure EDC-tar from silica sand porous media. Furthermore, separation of EDC-tar in the surfactant solution was conducted employing a salting-out effect. Significant separation of DNAPL was observed when 13 wt.% or more NaCl was added to the solution. Overall, this study evaluates the feasibility of using SEAR for remediating EDC-tar contaminated subsurface soil and groundwater.

  14. Remediation of groundwater contaminated with DNAPLs by biodegradable oil emulsion.

    Science.gov (United States)

    Lee, Young-Chul; Kwon, Tae-Soon; Yang, Jung-Seok; Yang, Ji-Won

    2007-02-01

    Emulsion-based remediation with biodegradable vegetable oils was investigated as an alternative technology for the treatment of subsurface DNAPLs (dense non-aqueous phase liquids) such as TCE (trichloroethylene) and PCE (perchloroethylene). Corn and olive oil emulsions obtained by homogenization at 8000rpm for 15min were used. The emulsion droplets prepared with corn and olive oil gave a similar size distribution (1-10microm) and almost all of initially injected oil, >90%, remained in a dispersed state. In batch experiments, 2% (v/v) oil emulsion could adsorb up to 11,000ppm of TCE or 18,000ppm of PCE without creating a free phase. Results of one-dimensional column flushing studies indicated that contaminants with high aqueous solubility could be efficiently removed by flushing with vegetable oil emulsions. Removal efficiencies exceeded 98% for TCE and PCE with both corn and olive oil emulsions. The results of this study show that flushing with biodegradable oil emulsion can be used for the remediation of groundwater contaminated by DNAPLs.

  15. New Developments in Contaminant Remediation by Smoldering Combustion

    Science.gov (United States)

    Gerhard, J.; Torero, J. L.; Major, D.; Grant, G.; Scholes, G.; Pironi, P.; Hasan, T.; Salman, M.

    2012-12-01

    In 2006 a new concept for the remediation of soils contaminated with non-aqueous phase liquids (NAPLs) was introduced (Gerhard et al., 2006, AGU Fall Meeting, H24A-01 INVITED). Proof of concept experiments had demonstrated that organic liquids, such as coal tar, could be destroyed via self-sustaining smoldering. Smoldering is an exothermic oxidation reaction in which organic material is converted primarily to energy, water, and carbon dioxide. Unlike flaming combustion, it is a surface reaction and the process is self-sustaining because the process provides (and the system retains) sufficient energy to propagate itself following a one-time, local ignition event (charcoal smoldering in a barbeque is a common example). The technique is promising for the effective destruction of NAPL-contaminated soil in a manner that is cost effective, low energy, and rapid. This presentation will provide an overview of the active and diverse research program underway since the initial proof of concept. More than 80 column experiments have revealed how the rate of destruction can be controlled by the air flux provided and the sensitivity to key parameters including mean grain size, NAPL type, NAPL saturation, and water content. Studies on field soils received from more than 12 sites on 4 continents revealed that the process was robust across a wide range of soils, contaminants and contaminant concentrations. Two-dimensional experiments have revealed the differences between vertical and lateral propagation of a smoldering front and these results have been employed to provide confidence in a numerical model of the process that accounts for heterogeneity of soil properties. Pilot tests undertaken for the in situ treatment of coal tar below the water table at a former chemical manufacturing facility demonstrated self-sustaining NAPL destruction rates of more than 800 kg/day and propagation rates of more than 1.5 m/day. Pilot testing is also underway with an ex situ reactor for the

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

    Science.gov (United States)

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

    2012-11-01

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

  17. Use of iron-based technologies in contaminated land and groundwater remediation: A review

    Energy Technology Data Exchange (ETDEWEB)

    Cundy, Andrew B. [School of Environment and Technology, University of Brighton, Lewes Road, Brighton BN2 4GJ (United Kingdom)], E-mail: A.Cundy@brighton.ac.uk; Hopkinson, Laurence [School of Environment and Technology, University of Brighton, Lewes Road, Brighton BN2 4GJ (United Kingdom); Whitby, Raymond L.D. [School of Pharmacy and Biomolecular Sciences, University of Brighton, Lewes Road, Brighton BN2 4GJ (United Kingdom)

    2008-08-01

    Reactions involving iron play a major role in the environmental cycling of a wide range of important organic, inorganic and radioactive contaminants. Consequently, a range of environmental clean-up technologies have been proposed or developed which utilise iron chemistry to remediate contaminated land and surface and subsurface waters, e.g. the use of injected zero zero-valent iron nanoparticles to remediate organic contaminant plumes; the generation of iron oxyhydroxide-based substrates for arsenic removal from contaminated waters; etc. This paper reviews some of the latest iron-based technologies in contaminated land and groundwater remediation, their current state of development, and their potential applications and limitations.

  18. Remediation of cyanide-contaminated industrial sites through woody biomass production

    Science.gov (United States)

    Dimitrova, Tsvetelina; Repmann, Frank; Freese, Dirk

    2017-04-01

    Due to the unfavourable chemical and physical soil quality parameters and the potential presence of contaminants, former industrial sites can hardly be utilized as arable land and can thus be classified as marginal areas. Still, as far as possible, they can effectively be used for the production of alternative energy, including the cultivation of fast growing trees. Apart from being a source of bioenergy, trees might facilitate the stabilization, remedation, contaminant extraction and degradation and, not on the last place, to enhance soil quality improvement on former industrial areas. This process is known as phytoremediation and has successfully been applied on industrial sites of various organic and inorganic contamination. The former manufactured gas plant site ( 2500 m2) "ehemalige Leuchtgasanstalt" Cottbus, contaminated, among others, with iron cyanides undergoes phytoremediation with simultaneous biomass production since 2011. The project "Biomass-Remediation" is fully financed by the German Railways JSC. A dense (23700 stems/ha), mixed cover of willow (Salix caprea), poplar (Populus maximowicii Henry x Populus trichocarpa Torr. et Gray (Hybrid 275)) and black locust (Robinia pseudoaccacia) trees has been planted on the site. Throughout the five years of remediation, a successful long-term stabilization of the site has been achieved as a result of the nearly outright established tree stock and the dense planting. Annual monitoring of the cyanide levels in the leaf tissue of the trees on the site and results from greenhouse experiments indicate the ability of all tree species to extract and transport the cyanide from the soil. Additonally, the greenhouse experiments suggest that the willows might be able, although not to a full extent, to detoxify the contaminant by splitting the CN moiety. The contaminated biomass material might easily be dealt with through regular harvests and subsequent incineration. Phytoremediation with simultaneous biomass production

  19. Monitoring of Soil Remediation Process in the Metal Mining Area

    Science.gov (United States)

    Kim, Kyoung-Woong; Ko, Myoung-Soo; Han, Hyeop-jo; Lee, Sang-Ho; Na, So-Young

    2016-04-01

    Stabilization using proper additives is an effective soil remediation technique to reduce As mobility in soil. Several researches have reported that Fe-containing materials such as amorphous Fe-oxides, goethite and hematite were effective in As immobilization and therefore acid mine drainage sludge (AMDS) may be potential material for As immobilization. The AMDS is the by-product from electrochemical treatment of acid mine drainage and mainly contains Fe-oxide. The Chungyang area in Korea is located in the vicinity of the huge abandoned Au-Ag Gubong mine which was closed in the 1970s. Large amounts of mine tailings have been remained without proper treatment and the mobilization of mine tailings can be manly occurred during the summer heavy rainfall season. Soil contamination from this mobilization may become an urgent issue because it can cause the contamination of groundwater and crop plants in sequence. In order to reduce the mobilization of the mine tailings, the pilot scale study of in-situ stabilization using AMDS was applied after the batch and column experiments in the lab. For the monitoring of stabilization process, we used to determine the As concentration in crop plants grown on the field site but it is not easily applicable because of time and cost. Therefore, we may need simple monitoring technique to measure the mobility or leachability which can be comparable with As concentration in crop plants. We compared several extraction methods to suggest the representative single extraction method for the monitoring of soil stabilization efficiency. Several selected extraction methods were examined and Mehlich 3 extraction method using the mixture of NH4F, EDTA, NH4NO3, CH3COOH and HNO3 was selected as the best predictor of the leachability or mobility of As in the soil remediation process.

  20. 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

    little attention in established life cycle impact assessment methodologies. Often groundwater is included in a general freshwater compartment, is simply disregarded, or is only functioning as a sink for contaminant emissions. When applying LCA for decision support for contaminated site remediation...

  1. Environmental assessment of contaminated site remediation in a life cycle perspective

    DEFF Research Database (Denmark)

    Lemming, Gitte

    the subsurface. This PhD project investigated the applicability of life cycle assessment as a tool for environmental assessment of remediation of contaminated sites. This was done focusing specifically on chloroethene-contaminated sites and remediation technologies relevant for this type of contaminant. LCA...... is an environmental assessment tool that compiles a very wide array of environmental exchanges (emissions to air, water, and soil, and resource consumption) associated with the life cycle of a product or service .and translates them to impacts (global warming, acidification, human toxicity, ecotoxicity, etc...... barrier. Thus, the majority of innovative in situ remediation methods for chloroethene source zone remediation were not covered in the literature. Within the project, life cycle assessments of remediation alternatives for source zone remediation of two chloroethene-contaminated sites were performed...

  2. Bioremediation in oil-contaminated sites: bacteria and surfactant accelerated remediation

    Science.gov (United States)

    Strong-Gunderson, Janet M.; Guzman, Francisco

    1996-11-01

    In Mexico, there are several environmental issues which are being addressed under the current governmental legislation. One important issue is restoring sites belonging to Petroleos Mexicanos (PEMEX). PEMEX is a large government owned oil company that regulates and manages the oil reserves. These sites are primarily contaminated with weathered hydrocarbons which are a consequence of extracting millions of barrels of oil. Within the southern regions of Mexico there are sites which were contaminated by activities and spills that have occurred during the past 30 years. PEMEX has taken the leadership in correcting environmental problems and is very concerned about cleaning up the contaminated sites as quickly as possible. The most significant contaminated sites are located to the north of Veracruz and south of Tabasco. These sites areas are close to refineries or locations of oil exploration. The primary category of contaminants are hydrocarbons, among them asphaltens, aromatic and other contaminants. The concentration of the contaminants varies depending on the location of the sites, but it can reach as high as 500,000 ppm. PEMEX has been searching for appropriate, and cost- effective technologies to clean up these sites. Biologically based remediation activities are of primary interest to PEMEX. However, other treatment technologies such as chemical-physical methods, encapsulation and incineration are also being considered. The present report summarizes preliminary experiments that measured the feasibility of bioremediation for a contaminated site in southern Mexico.

  3. Remediation of Heavy Metal(loid)s Contaminated Soils – To Mobilize or To Immobilize?

    Science.gov (United States)

    Unlike organic contaminants, metal(loid)s do not undergo microbial or chemical degradation and persist for a long time after their introduction. Bioavailability of metal(loid)s plays a vital role in the remediation of contaminated soils. In this review, the remediation of heavy ...

  4. A Fuzzy Simulation-Based Optimization Approach for Groundwater Remediation Design at Contaminated Aquifers

    Directory of Open Access Journals (Sweden)

    A. L. Yang

    2012-01-01

    Full Text Available A fuzzy simulation-based optimization approach (FSOA is developed for identifying optimal design of a benzene-contaminated groundwater remediation system under uncertainty. FSOA integrates remediation processes (i.e., biodegradation and pump-and-treat, fuzzy simulation, and fuzzy-mean-value-based optimization technique into a general management framework. This approach offers the advantages of (1 considering an integrated remediation alternative, (2 handling simulation and optimization problems under uncertainty, and (3 providing a direct linkage between remediation strategies and remediation performance through proxy models. The results demonstrate that optimal remediation alternatives can be obtained to mitigate benzene concentration to satisfy environmental standards with a minimum system cost.

  5. Public perceptions of a radioactively contaminated site: concerns, remediation preferences, and desired involvement.

    OpenAIRE

    1996-01-01

    A public attitudes survey was conducted in neighborhoods adjacent to a radioactively contaminated site whose remediation is now under the auspices of the U.S. Department of Energy's Formerly Utilized Sites Remedial Action Program (FUSRAP). The survey's purpose was to ascertain levels of actual and desired public involvement in the remediation process; to identify health, environmental, economic, and future land-use concerns associated with the site; and to solicit remediation strategy prefere...

  6. Bioavailability enhanced rhizosphere remediation of petroleum hydrocarbon contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Marchenko, A.; Vorobyov, A.; Zharikov, G.; Ermolenko, Z.; Dyadishchev, N.; Borovick, R.; Sokolov, M. [Research Centre for Toxicology and Hygienic Regulation of Biopreparations, Moscow region (Russian Federation); Ortega-Calvo, J.J. [Instituto de Recursos Naturales y Agrobiologia, CSIC, Sevilla (Spain)

    2005-07-01

    contain were analyzed by gas chromatography method. Four bioassays were used to measure toxicity during bio-remediation of soil contaminated by petroleum hydrocarbons: Microtox(R) test, SOSchromotest, lettuce seed germination and sheep red blood cell (RBS) hemolysis assay. Rhizosphere remediation was found to be effective for removal of polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPHs) from soil with the use of alfalfa inoculated by the Pseudomonas stutzeri MEV-S1 strain (RU 2228952 patent) and oats inoculated by the Pseudomonas alcaligenes MEV strain (RU 2228953 patent) in vegetation and field experiments. The reduction of the TPH and PAH concentrations in soil was accompanied by the reduction of integral toxicity and genotoxicity, evaluated by bio-testing. It is conceivable, therefore, that a possible way to optimize petroleum hydrocarbons phyto-remediation is the use of selected plants and microbial inoculants with specific chemotactic affinities and bio-surfactant production. The proposed technology for soil bio-remediation with the use of integrated plant-microbial system is ecologically and toxicologically safe and economically attractive.

  7. Remediation of lead and cadmium-contaminated soils.

    Science.gov (United States)

    Salama, Ahmed K; Osman, Khaled A; Gouda, Neama Abdel-Razeek

    2016-01-01

    The research was designated to study the ability of plants to bio-accumulate, translocate and remove the heavy metals, lead and cadmium from contaminated soil. The herbal plant ryegrass, Lolium multiflorum was investigated as a bio-accumulator plant for these metals. The translocation of these heavy metals in the herbal plant was compared considering root to shoot transport and redistribution of metals in the root and shoot system. The trace metal contents from root and shoot parts were determined using atomic absorption spectrometer. The results showed that the percent of lead and cadmium transferred to ryegrass plant were averaged as 51.39, and 74.57%, respectively, while those remained in the soil were averaged as 48.61 and 25.43% following 60 days of treatment. The soil-plant transfer index in root and shoot system of ryegrass was found to be 0.32 and 0.20 for lead, and 0.50 and 0.25 for cadmium. These findings indicated that the herbal plant ryegrass, Lolium multiflorum is a good accumulator for cadmium than lead. The soil-plant transfer factor (the conc. of heavy metal in plant to the conc. in soil) indicated that the mechanism of soil remedy using the investigated plant is phytoextraction where the amounts of heavy metals transferred by plant roots into the above ground portions were higher than that remained in the soil. The method offers green technology solution for the contamination problem since it is effective technology with minimal impact on the environment and can be easily used for soil remedy.

  8. Volumetric scale-up of smouldering remediation of contaminated materials.

    Science.gov (United States)

    Switzer, Christine; Pironi, Paolo; Gerhard, Jason I; Rein, Guillermo; Torero, Jose L

    2014-03-15

    Smouldering remediation is a process that has been introduced recently to address non-aqueous phase liquid (NAPL) contamination in soils and other porous media. Previous work demonstrated this process to be highly effective across a wide range of contaminants and soil conditions at the bench scale. In this work, a suite of 12 experiments explored the effectiveness of the process as operating scale was increased 1000-fold from the bench (0.003m(3)) to intermediate (0.3m(3)) and pilot field-scale (3m(3)) with coal tar and petrochemical NAPLs. As scale increased, remediation efficiency of 97-99.95% was maintained. Smouldering propagation velocities of 0.6-14×10(-5)m/s at Darcy air fluxes of 1.54-9.15cm/s were consistent with observations in previous bench studies, as was the dependence on air flux. The pilot field-scale experiments demonstrated the robustness of the process despite heterogeneities, localised operation, controllability through airflow supply, and the importance of a minimum air flux for self-sustainability. Experiments at the intermediate scale established a minimum-observed, not minimum-possible, initial concentration of 12,000mg/kg in mixed oil waste, providing support for the expectation that lower thresholds for self-sustaining smouldering decreased with increasing scale. Once the threshold was exceeded, basic process characteristics of average peak temperature, destructive efficiency, and treatment velocity were relatively independent of scale. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Remediation of Legacy Arsenic Mining Areas in Yunnan Province, China

    Directory of Open Access Journals (Sweden)

    Ian H. von Lindern

    2011-01-01

    Conclusions. The success of the demonstration project was recognized and has provided direction and momentum for a wider effort by the Province to address mining pollution and water contamination challenges. It demonstrates the success of using known techniques for environmental remediation in the US, with local partners in China responding to their communities’ health and environmental problems.

  10. Characteristics of biochar and its application in remediation of contaminated soil.

    Science.gov (United States)

    Tang, Jingchun; Zhu, Wenying; Kookana, Rai; Katayama, Arata

    2013-12-01

    Biochar is produced by thermal decomposition of biomass under oxygen-limited conditions (pyrolysis), and it has received attention in soil remediation and waste disposal in recent years. The characteristics of biochar are influenced mainly by the preparation temperature and biomass. Higher pyrolysis temperature often results in the increased surface area and carbonized fraction of biochar leading to high sorption capability for pollutants. Biochars derived from various source materials show different properties of surface area, porosity and the amount of functional groups which are important concerning on the effect of biochar. Biochar has been proved to be effective in improving soil properties and increasing crop biomass. It has also been suggested that it can even enhance crop resistance to disease. Biochar has recently been used to remediate soil with both heavy metal and organic pollutants. The mechanism is electrostatic interaction and precipitation in the case of heavy metal, and the surface adsorption, partition and sequestration in the case of organic contaminants. However, application of biochar in soil has been shown to result in decreased efficacy of pesticides, which indicates a trade-off between the potentially promising effect of biochar on pesticide remediation and its negative effect on pesticide efficacy. While arguments on the effectiveness of biochar appear sound, further research is needed prior to widespread application of biochar in soil remediation.

  11. [Urban industrial contaminated sites: a new issue in the field of environmental remediation in China].

    Science.gov (United States)

    Liao, Xiao-Yong; Chong, Zhong-Yi; Yan, Xiu-Lan; Zhao, Dan

    2011-03-01

    Contamination of urban industrial lands is a new environmental problem in China during the process of upgrade of industrial structure and adjustment of urban layout. It restricts the safe re-use of urban land resources, and threatens the health of surrounding inhabitants. In the paper, the market potential of contaminated-site remediation was known through analysis of spatial distribution of urban industrial sites in China. Remediation technologies in the Occident which were suitable for urban industrial contaminated sites were discussed and compared to evaluate their superiority and inferiority. And then, some advices of remediation technologies for urban industrial contaminated sites in China were proposed.

  12. Remediation of Contaminated Soils By Supercritical Carbon Dioxide Extraction

    Science.gov (United States)

    Ferri, A.; Zanetti, M. C.; Banchero, M.; Fiore, S.; Manna, L.

    The contaminants that can be found in soils are many, inorganic, like heavy metals, as well as organic. Among the organic contaminants, oil and coal refineries are responsi- ble for several cases of soil contamination with PAHs (Polycyclic Aromatic Hydrocar- bons). Polynuclear aromatic hydrocarbons (PAHs) have toxic, carcinogenic and mu- tagenic effects. Limits have been set on the concentration of most contaminants, and growing concern is focusing on soil contamination issues. USA regulations set the maximum acceptable level of contamination by PAHs equal to 40 ppm at residential sites and 270 ppm at industrial sites. Stricter values are usually adopted in European Countries. Supercritical carbon dioxide extraction is a possible alternative technology to remove volatile organic compounds from contaminated soils. Supercritical fluid extraction (SFE) offers many advantages over conventional solvent extraction. Super- critical fluids combine gaseous properties as a high diffusion coefficient, and liquid properties as a high solvent power. The solvent power is strongly pressure-dependent near supercritical conditions: selective extractions are possible without changing the solvent. Solute can be separate from the solvent depressurising the system; therefore, it is possible to recycle the solvent and recover the contaminant. Carbon dioxide is frequently used as supercritical fluid, because it has moderate critical conditions, it is inert and available in pure form. In this work, supercritical fluid extraction technology has been used to remove a polynuclear aromatic hydrocarbon from contaminated soils. The contaminant choice for the experiment has been naphthalene since several data are available in literature. G. A. Montero et al. [1] studied soil remediation with supercrit- ical carbon dioxide extraction technology; these Authors have found that there was a mass-transfer limitation. In the extraction vessel, the mass transfer coefficient in- creases with the

  13. Phytoremediation Possibilities for Contaminated Mining Areas from Romania

    Directory of Open Access Journals (Sweden)

    COMAN Mirela

    2009-12-01

    Full Text Available Mining activities, which have been carried out in Romania for centuries, resulted in pollution of large areas,affecting negatively the environment and representing a threat for human health. This paper aims to prove that inRomania can host a relatively new, costly efficient and sustainable remediation technique for contaminated miningsites, namely phytoremediation. The applicability of phytoremediation for remediation of contaminated areas wasproven by several demonstration projects carried out worldwide. It has a very positive impact on the landscapeaesthetics, resulting in a high public acceptability. Moreover, the climate and soil conditions in Romania allow the useof several plant species which can remove contaminants from water and soil. It is therefore concluded that thesuccessful implementation of phytoremediation on contaminated mining sites in Romania can be achieved, but undercertain conditions. These conditions include the promotion of this technology by finding appropriate ways to transferknow-how and to build capacity at the level of public institutions and organizations dealing with remediation of themining areas.

  14. Examples from the Greenland-Project - Gentle Remediation Optiones (GROs) on Pb/zn Contaminated Sites

    Science.gov (United States)

    Friesl-Hanl, Wolfgang; Kidd, Petra; Siebielec, Grzegorz

    2017-04-01

    The GREENLAND-project brought together "best practice" examples of several field applied gentle remediation techniques (EUFP7-project "Gentle remediation of trace element-contaminated land - GREENLAND; www.greenland-project.eu) with 17 partners from 11 countries. Gentle remediation options (GRO) comprise environmentally friendly technologies that have little or no negative impact on the soil. The main technologies are • phytoextraction • in situ immobilization and • assisted phytostabilization. Mining and processing activities affecting many sites worldwide negatively. The huge amounts of moved and treated materials have led to considerable flows of wastes and emissions. Alongside the many advantages of processed ores to our society, adverse effects in nature and risks for the environment and human health are observed. Three stages of impact of Pb/Zn-ore-treatment on the environment are discussed here: (1) On sites where the ores are mined impacts are the result of crushing, grinding, concentrating activities, and where additionally parts of the installations remain after abandoning the mine, as well as by the massive amounts of remaining deposits or wastes (mine tailings). (2) On sites where smelting and processing takes place, depending on the process (Welz, Doerschel) different waste materials are deposited. The Welz process waste generally contains less Cd and Pb than the Doerschel process waste which additionally shows higher water- extractable metals. (3) On sites close to the emitting source metal contamination can be found in areas for housing, gardening, and agricultural use. Emissions consist mainly from oxides and sulfides (Zn, Cd), sulfates (Zn, Pb, and Cd), chlorides (Pb) and carbonates (Cd). All these wastes and emissions pose potential risks of dispersion of pollutants into the food chain due to erosion (wind, water), leaching and the transfer into feeding stuff and food crops. In-situ treatments have the potential for improving the situation

  15. Remediation of a Mercury-Contaminated Industrial Soil Using Bioavailable Contaminant Stripping

    Institute of Scientific and Technical Information of China (English)

    F.PEDRON; G.PETRUZZELLI; M.BARBAFIERI; E.TASSI

    2013-01-01

    The method to remove bioavailable amounts of heavy metals from a contaminated soil by using plants is defined as bioavailable contaminant stripping (BCS) and could safely be applied if the soil's long-term ability to replenish the bioavailable pool is known.The aim of this study was to evaluate the ability of three common plant species selected,Brassica juncea,Poa annua,and Helianthus annus,to remove bioavailable amounts of mercury (Hg) from a contaminated industrial soil containing 15.1 mg kg-1 Hg.Trials were carried out under greenhouse conditions using pots (mesocosms).According to the precautionary principle,we modified the BCS remediation approach by adding a new step,in which mercury bioavailability was increased by the addition of a strong mobilizing agent,ammonium thiosulphate,(NH4)2S2O3,to obtain an estimate of the likely long-term bioavailable Hg pool.The modified BCS remediation approach was called enhanced bioavailable contaminant stripping (EBCS).After one growth cycle,nearly all the bioavailable mercury (95.7%) was removed and the metal remaining in the soil was considered inert since it was neither extractable by (NH4)2S2O3 nor taken up by plants during a second growth cycle.The results demonstrated that EBCS appeared promising since it removed the most dangerous metal forms while substantially shortening the cleanup time.

  16. Idaho National Laboratory Test Area North: Application of Endpoints to Guide Adaptive Remediation at a Complex Site: INL Test Area North: Application of Endpoints

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M. Hope [PNNL Soil and Groundwater Program; Truex, Mike [PNNL; Freshley, Mark [PNNL; Wellman, Dawn [PNNL

    2016-09-01

    Complex sites are defined as those with difficult subsurface access, deep and/or thick zones of contamination, large areal extent, subsurface heterogeneities that limit the effectiveness of remediation, or where long-term remedies are needed to address contamination (e.g., because of long-term sources or large extent). The Test Area North at the Idaho National Laboratory, developed for nuclear fuel operations and heavy metal manufacturing, is used as a case study. Liquid wastes and sludge from experimental facilities were disposed in an injection well, which contaminated the subsurface aquifer located deep within fractured basalt. The wastes included organic, inorganic, and low-level radioactive constituents, with the focus of this case study on trichloroethylene. The site is used as an example of a systems-based framework that provides a structured approach to regulatory processes established for remediation under existing regulations. The framework is intended to facilitate remedy decisions and implementation at complex sites where restoration may be uncertain, require long timeframes, or involve use of adaptive management approaches. The framework facilitates site, regulator, and stakeholder interactions during the remedial planning and implementation process by using a conceptual model description as a technical foundation for decisions, identifying endpoints, which are interim remediation targets or intermediate decision points on the path to an ultimate end, and maintaining protectiveness during the remediation process. At the Test Area North, using a structured approach to implementing concepts in the endpoint framework, a three-component remedy is largely functioning as intended and is projected to meet remedial action objectives by 2095 as required. The remedy approach is being adjusted as new data become available. The framework provides a structured process for evaluating and adjusting the remediation approach, allowing site owners, regulators, and

  17. Electrokinetic remediation and microbial community shift of β-cyclodextrin-dissolved petroleum hydrocarbon-contaminated soil.

    Science.gov (United States)

    Wan, Chunli; Du, Maoan; Lee, Duu-Jong; Yang, Xue; Ma, Wencheng; Zheng, Lina

    2011-03-01

    Electrokinetic (EK) migration of β-cyclodextrin (β-CD), which is inclusive of total petroleum hydrocarbon (TPH), is an economically beneficial and environmentally friendly remediation process for oil-contaminated soils. Remediation studies of oil-contaminated soils generally prepared samples using particular TPHs. This study investigates the removal of TPHs from, and electromigration of microbial cells in field samples via EK remediation. Both TPH content and soil respiration declined after the EK remediation process. The strains in the original soil sample included Bacillus sp., Sporosarcina sp., Beta proteobacterium, Streptomyces sp., Pontibacter sp., Azorhizobium sp., Taxeobacter sp., and Williamsia sp. Electromigration of microbial cells reduced the biodiversity of the microbial community in soil following EK remediation. At 200 V m(-1) for 10 days, 36% TPH was removed, with a small population of microbial cells flushed out, demonstrating that EK remediation is effective for the present oil-contaminated soils collected in field.

  18. Addendum to the East Tennessee Technology Park Site-Wide Residual Contamination Remedial Investigation Work Plan Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    SAIC

    2011-04-01

    The East Tennessee Technology Park Site-Wide Residual Contamination Remedial Investigation Work Plan (DOE 2004) describes the planned fieldwork to support the remedial investigation (RI) for residual contamination at the East Tennessee Technology Park (ETTP) not addressed in previous Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) decisions. This Addendum describes activities that will be conducted to gather additional information in Zone 1 of the ETTP for groundwater, surface water, and sediments. This Addendum has been developed from agreements reached in meetings held on June 23, 2010, August 25, 2010, October 13, 2010, November 13, 2010, December 1, 2010, and January 13, 2011, with representatives of the U. S. Department of Energy (DOE), U. S. Environmental Protection Agency (EPA), and Tennessee Department of Environment and Conservation (TDEC). Based on historical to recent groundwater data for ETTP and the previously completed Sitewide Remedial Investigation for the ETTP (DOE 2007a), the following six areas of concern have been identified that exhibit groundwater contamination downgradient of these areas above state of Tennessee and EPA drinking water maximum contaminant levels (MCLs): (1) K-720 Fly Ash Pile, (2) K-770 Scrap Yard, (3) Duct Island, (4) K-1085 Firehouse Burn/J.A. Jones Maintenance Area, (5) Contractor's Spoil Area (CSA), and (6) Former K-1070-A Burial Ground. The paper presents a brief summary of the history of the areas, the general conceptual models for the observed groundwater contamination, and the data gaps identified.

  19. Enhanced remediation of Cr(VI)-contaminated soil by incorporating a calcined-hydrotalcite-based permeable reactive barrier with electrokinetics.

    Science.gov (United States)

    Zhang, Jia; Xu, Yunfeng; Li, Wentao; Zhou, Jizhi; Zhao, Jun; Qian, Guangren; Xu, Zhi Ping

    2012-11-15

    This paper describes the enhanced Cr(VI)-contaminated soil remediation via a combination of electrokinetics (EK) with a calcined-hydrotalcite-based permeable reactive barrier (PRB). First, this combination proved to be feasible, and remarkably facilitated Cr(VI) remediation in a column test. Then, lightly-to-severely (0.16-1.65 mg/g) Cr(VI)-contaminated soil was remediated in a simulated test with the calcined hydrotalcite as the PRB under an voltage of 10-30 V (i.e. an electric field intensity of 0.7-2.0 V/cm). The observations demonstrated that both PRB and EK are critical to efficient remediation and the high de-contamination efficiency is supposedly attributed to the synergistic effect, for which EK concentrates anionic chromate to the anode region and PRB media (calcined hydrotalcite) absorbs and immobilizes it. Thus we have shown that the combined PRB-EK system is highly adaptive and effective in remediation of a larger area contaminated with chromate and various anionic pollutants.

  20. Assessing Alternative Endpoints for Groundwater Remediation at Contaminated Sites

    Science.gov (United States)

    2011-05-01

    OSWER Office of Solid Waste and Emergency Response OU operable unit PAH poly-aromatic hydrocarbon PCB poly-chlorinated biphenyl PCE...consisting of source treatment in three source areas (permanganate injections, molasses injections to enhance biodegradation , and vacuum-enhanced vapor...contaminated with wood treatment compounds and fuel oil (coal tar creosote, poly-aromatic hydrocarbons ( PAHs ), pentachlorophenol, arsenic, chromium, copper

  1. Feasibility Process for Remediation of the Crude Oil Contaminated Soil

    Science.gov (United States)

    Keum, H.; Choi, H.; Heo, H.; Lee, S.; Kang, G.

    2015-12-01

    More than 600 oil wells were destroyed in Kuwait by Iraqi in 1991. During the war, over 300 oil lakes with depth of up to 2m at more than 500 different locations which has been over 49km2. Therefore, approximately 22 million m3was crude oil contaminated. As exposure of more than 20 years under atmospheric conditions of Kuwait, the crude oil has volatile hydrocarbons and covered heavy oily sludge under the crude oil lake. One of crude oil contaminated soil which located Burgan Oilfield area was collected by Kuwait Oil Company and got by H-plus Company. This contaminated soil has about 42% crude oil and could not biodegraded itself due to the extremely high toxicity. This contaminated soil was separated by 2mm sieve for removal oil sludge ball. Total petroleum hydrocarbons (TPH) was analysis by GC FID and initial TPH concentration was average 48,783 mg/kg. Ten grams of the contaminated soil replaced in two micro reactors with 20mL of bio surfactant produce microorganism. Reactor 1 was added 0.1g powder hemoglobin and other reactor was not added hemoglobin at time 0 day. Those reactors shake 120 rpm on the shaker for 7 days and CO2 produced about 150mg/L per day. After 7 days under the slurry systems, the rest days operated by hemoglobin as primary carbon source for enhanced biodegradation. The crude oil contaminated soil was degraded from 48,783mg/kg to 20,234mg/kg by slurry process and final TPH concentration degraded 11,324mg/kg for 21days. Therefore, highly contaminated soil by crude oil will be combined bio slurry process and biodegradation process with hemoglobin as bio catalytic source. Keywords: crude-oil contaminated soil, bio slurry, biodegradation, hemoglobin ACKOWLEDGEMENTS This project was supported by the Korea Ministry of Environment (MOE) GAIA Program

  2. Using multiple indices to evaluate scenarios for the remediation of contaminated land: the Porto Marghera (Venice, Italy) contaminated site.

    Science.gov (United States)

    Critto, Andrea; Agostini, Paola

    2009-09-01

    technologies and for the spatial distribution of the technologies on the considered area. Indices results allow the user to more easily evaluate the advantages and limits of each scenario in order to select the most appropriate one. For instance, the risk indices allow the user to identify scenarios with good performance in reducing the extension of risk areas and the risk magnitude. Equally, the technological indices support the achievement of efficient remedial solutions characterized by a limited number of technologies, applied to extended areas and with high performance. The environmental impact index allows users to estimate the wider effects on the environment of the selected solutions, while the socioeconomic index is the result of social and economic investigations of the regional and local conditions, which ends with the identification of the best land use (e.g., the industrial one for the Porto Marghera area). The proposed nine DESYRE indices provide more complete information to investigate suitable management solutions. DESYRE indices facilitate the definition of a consensus among stakeholders and the achievement of a widely shared solution for contaminated site management, even at larger sites, such as Porto Marghera. Further improvements to the system may be adopted, e.g., the possibility to aggregate results of the different assessments into one synthetic index per scenario or the inclusion of a Group Decision Making procedure.

  3. 改性污泥对矿区铜、镉污染土壤的修复%Remediation of copper and cadmium contamination in farmland surrounding mining area with modified sludge

    Institute of Scientific and Technical Information of China (English)

    丁园; 吴余金; 郝双龙; 史蓉蓉

    2014-01-01

    evaluated for remediation of copper and cadmium contaminated soils affected by a copper mine. The test paddy soils were sampled from the farmland surrounding mining area in Jiangxi province. TCLP (Toxicity characteristic leaching procedure) leaching contents of Cu and Cd in soil were 40.34 mg·kg-1 and 660.1μg·kg-1 respectively, of which the Cu concentration was higher than the international standard value of 15 mg·kg-1. The sludge was applied to soil at four rates (1%, 3%, 5% and 10% of soil weight) and compared with no sludge treatment. After 30 days of soil incubation in lab, bioavailability and fraction change of Cu and Cd as well as protease and urease activities of the test soil were analyzed to evaluate the remediation effect and its mechanism. The results showed that modified sludge could deactivate soil Cu significantly, and the more the sludge was applied, the greater deactivation effect could be observed. When the sludge was applied at the rate of 5%of the soil weight, TCLP leaching content of soil Cu decreased to 12.03 mg·kg-1, which was lower than the standard limitation. Modified sludge could also deactivate soil Cd, but the deactivation effect was less marked than soil Cu. When the sludge was applied at the rate of 1%, leaching content of soil Cd increased conversely compared with control. However, when the rate was 5%, leaching content of soil Cd decreased to 539.6μg·kg-1. Results of sequential extraction procedure showed that the main fractions of Cu were carbonate-bound, organic-bound and residual Cu. When the sludge application rate was 5%, the percentage of exchangeable Cu decreased from 8.10% to 4.10 %, while the percentage of organic-bound Cu increased from 26.45% to 32.34%. Meanwhile, the percentage of exchangeable Cd reduced from 36.80% to 30.69%. So the transformation of Cu and Cd fractions caused by the modified sludge was mainly between exchangeable concentration and organic-bound concentration, which led to the decline of Cu and Cd

  4. Establishment of criteria for classification of area remediation measures contaminated after an eventual radiation accident in Angra dos Reis, RJ, nuclear power plant; Estabelecimento de criterios para a classificacao de medidas de remediacao de areas contaminadas apos um eventual acidente nuclear na usina de Angra dos Reis (RJ)

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Diogo Neves Gomes da

    2016-07-01

    When a radiological or nuclear accident that leads to the release of radioactive material to the environment occurs, it is important to implement protective and remediation measures in order to reduce human exposure to radionuclides. Therefore, it is necessary that the procedures to be chosen by the affected country authorities are the most efficient ones, which can only be defined based on previously established criteria. In Brazil, since the radiological accident in Goiania, in 1987, the development of tools to support decision-making in emergencies of this nature was started. The main objective of this work was to establish an acting basis for contaminated areas, in order to protect the individuals of public in case of any accident related to Almirante Alvaro Alberto nuclear power plant, in the municipality of Angra dos Reis (RJ), which leads to contamination to the environment and the consequent exposure of local population or from more distant regions to ionizing radiation. Initially, the high-risk areas near the location of the nuclear power plant were defined. Typical urban environments found in the main cities of these municipalities were surveyed, including homes, streets and recreation areas. The main characteristics of the study area were evaluated using images from Google Earth® and web pages of the municipalities. After the types of areas to be simulated were selected, these were quantified in terms of the number of residents, the size of the streets, and the number of trees, among others, per unit area. Considering the different housing characteristics for the selected municipalities, six main standard scenarios were developed for urban areas, including homes with different shielding, buildings and parks. The simulation of the procedures for each scenario was made with SIEM model, developed by the Institute of Radiation Protection and Dosimetry (IRD/CNEN), formed by the integration of various models including CORAL, focusing on agricultural areas

  5. Phyto-remediation of contaminated soils; La phytoremediation des sols contamines

    Energy Technology Data Exchange (ETDEWEB)

    Morel, J.L. [Ecole Nationale Superieure Agronomie et des Industries Alimentaires, 54 - Vandoeuvre les Nancy (France)

    2002-09-01

    Plants provide new ways for soil remediation. The activity of living roots (absorption, exudation of organic compounds, action on physical soil properties) contribute to decrease the negative effects of pollutants, as they are stabilised or eliminated (extraction or degradation). In the presence of plants, hydrocarbons, a rather ubiquitous group of soil pollutants, are degraded faster than in bare soil. Hydrocarbon degrading bacteria are stimulated by root exudates, which also create favourable conditions for co-metabolism. Also, the fragmentation of aggregates as well as the release of surfactants increase the exposure of organic pollutants to microorganism degradation. The phyto-remediation technology is efficient to reduce the dissemination of pollutants. On historically contaminated soils, effects are generally discrete within a short period of time and may be more effective in the long run. (author)

  6. Research Progress of Artificial Forest in the Remediation of Heavy Metal Contaminated Soils

    Science.gov (United States)

    Jiafang, MA; Guangtao, MENG; Liping, HE; Guixiang, LI

    2017-01-01

    (1) Remediation of soil contaminated by heavy metals has become a hot topic in the world, and phytoremediation technology is the most widely used. (2) In addition to traditional economic benefits, ecological benefits of artificial forest have been more and more important, which are very helpful to soil polluted with heavy metals in the environment. (3) The characteristics of heavy metal pollution of soil and plantations of repair mechanism have been reviewed, and the current mining areas, wetlands, urban plantations on heavy metal elements have enriched the research results. The purpose is to find a new path for governance of heavy metal soil pollution.

  7. FY 1995 remedial investigation work plan for Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Watkins, D.R.; Herbes, S.E. [eds.

    1994-09-01

    Field activities to support the remedial investigation (RI) of Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL) include characterization of the nature and extent of contamination in WAG 2, specifically to support risk-based remediation decisions. WAG 2 is the major drainage system downgradient of other WAGs containing significant sources of contamination at ORNL. The RI of WAG 2 is developed in three phases: Phase 1, initial scoping characterization to determine the need for early action; Phase 2, interim activities during remediation of upgradient WAGs to evaluate potential changes in the contamination status of WAG 2 that would necessitate reevaluation of the need for early action; and Phase 3, completion of the RI process following remediation of upslope WAGs. Specifically, Phase 2 activities are required to track key areas to determine if changes have occurred in WAG 2 that would require (1) interim remedial action to protect human health and the environment or (2) changes in remedial action plans and schedules for WAG2 because of changing contaminant release patterns in upslope WAGs or because of the effects of interim remedial or removal actions in other WAGs. This report defines activities to be conducted in FY 1995 for completion of the Phase 1 RI and initiation of limited Phase 2 field work.

  8. Remediation of contaminated lands in the Niger Delta, Nigeria: Prospects and challenges.

    Science.gov (United States)

    Zabbey, Nenibarini; Sam, Kabari; Onyebuchi, Adaugo Trinitas

    2017-05-15

    Contamination of the total environment (air, soil, water and biota) by crude oil has become a paramount interest in the Niger Delta region of Nigeria. Studies have revealed variable impacts of oil toxicity on the environment and exposed populations. The revelation gained much international attention in 2011 with the release of Environmental Assessment of Ogoniland report by the United Nations Environment Programme (UNEP). This has up scaled local and international pressures for urgent clean-up and restoration of degraded bio-resource rich environments of the Niger Delta, starting from Ogoniland. Previous remediation attempts in the area had failed due to erroneous operational conclusions (such as conclusions by oil industry operators that the Niger Delta soil is covered by a layer of clay and as such oil percolation remains within the top soil and makes remediation by enhanced natural attenuation (RENA) suitable for the region) and the adoption of incompatible and ineffective approaches (i.e. RENA) for the complex and dynamic environments. Perennial conflicts, poor regulatory oversights and incoherent standards are also challenges. Following UNEP recommendations, the Federal Government of Nigeria recently commissioned the clean-up and remediation of Ogoniland project; it would be novel and trend setting. While UNEP outlined some measures of contaminated land remediation, no specific approach was identified to be most effective for the Niger Delta region. Resolving the technical dilemma and identified social impediments is the key success driver of the above project. In this paper, we reviewed the socio-economic and ecological impacts of contaminated land in the Niger Delta region and the global state-of-the-art remediation approaches. We use coastal environment clean-up case studies to demonstrate the effectiveness of bioremediation (sometimes in combination with other technologies) for remediating most of the polluted sites in the Niger Delta. Bioremediation

  9. Phytoremediation of dye contaminated soil by Leucaena leucocephala (subabul) seed and growth assessment of Vigna radiata in the remediated soil.

    Science.gov (United States)

    Jayanthy, V; Geetha, R; Rajendran, R; Prabhavathi, P; Karthik Sundaram, S; Dinesh Kumar, S; Santhanam, P

    2014-09-01

    The present study was investigated for soil bioremediation through sababul plant biomass (Leucaena leucocephala). The soil contaminated with textile effluent was collected from Erode (chithode) area. Various physico-chemical characterizations like N, P, and K and electrical conductivity were assessed on both control and dye contaminated soils before and after remediation. Sababul (L. leucocephala) powder used as plant biomass for remediation was a tool for textile dye removal using basic synthetic dyes by column packing and eluting. The concentration of the dye eluted was compared with its original concentration of dye and were analyzed by using UV-vis spectrophotometer. Sababul plant biomass was analyzed for its physico-chemical properties and active compounds were detected by GC-MS, HPTLC and FTIR. Plant growth was assessed with green gram on the textile contaminated soil and sababul had the potential of adsorbing the dye as the contaminated soil and also check the growth of green gram.

  10. Temporal biogeophysical signatures at hydrocarbon contaminated sites associated with long-term remediation efforts

    Science.gov (United States)

    Atekwana, E.; Che-Alota, V.; Atekwana, E.; Werkema, D. D.

    2009-05-01

    Biogeophysical signatures of hydrocarbon contaminated sites provide ideal laboratories for investigating microbial-geophysical relationships as the excess organic carbon present at these sites stimulates microbial activity. As such geophysical investigations have documented characteristic changes associated with hydrocarbon biodegradation in both field and laboratory experiments. The conceptual model that results from almost a decade of studies from these environments is one in which over time, the geophysical signatures due to bio-physicochemical changes imparted on the aquifer by the microbial activity reach some maximum or minimum related to the availability of terminal electron acceptors, the organic carbon source concentration, and microbial activity. However, with continuous removal of the contaminant mass either by natural attenuation (e.g., intrinsic bioremediation) or engineered (bio) remediation, a decrease in the microbial activity is predicted to cause associated changes in the geophysical properties (i.e., geophysical signatures revert to original conditions). This paper will present the results of repeated geophysical investigations at a hydrocarbon contaminated site acquired over an eleven-year period documenting changes in geophysical signatures associated with removal of hydrocarbon mass in the contaminated zone. Initial investigations at the site showed that relative to background, the contaminated area was characterized by higher bulk electrical conductivity, positive SP anomaly, and attenuated GPR reflections. Over time, the contaminated zone bulk electrical conductivity had reverted to near background conditions, the positive SP anomaly became more negative, and the zone of attenuated GPR reflections showed increased signal strength. The removal of hydrocarbon mass in the vadose zone over the plume by a soil vapor extraction system decreased the level of biological activity and therefore the magnitude of the geophysical signatures. We conclude

  11. Remediation of Cr(VI)-Contaminated Soil Using the Acidified Hydrazine Hydrate.

    Science.gov (United States)

    Ma, Yameng; Li, Fangfang; Jiang, Yuling; Yang, Weihua; Lv, Lv; Xue, Haotian; Wang, Yangyang

    2016-09-01

    Acidified hydrazine hydrate was used to remediate Cr(VI)-contaminated soil. The content of water-soluble Cr(VI) in contaminated soil was 4977.53 mg/kg. The optimal initial pH of hydrazine hydrate solution, soil to solution ratio and molar ratio of Cr(VI) to hydrazine hydrate for remediation of Cr(VI)-contaminated soil were 5.0, 3:1 and 1:3, respectively. Over 99.50 % of water-soluble Cr(VI) in the contaminated soil was reduced at the optimal condition within 30 min. The remediated soil can keep stable within 4 months. Meanwhile the total phosphorus increased from 0.47 to 4.29 g/kg, indicating that using of acidified hydrazine hydrate is an effective method to remediate Cr(VI)-contaminated soil.

  12. Remediation of contaminated soils by biotechnology with nanomaterials: bio-behavior, applications, and perspectives.

    Science.gov (United States)

    Gong, Xiaomin; Huang, Danlian; Liu, Yunguo; Peng, Zhiwei; Zeng, Guangming; Xu, Piao; Cheng, Min; Wang, Rongzhong; Wan, Jia

    2017-09-13

    Soil contamination caused by heavy metals and organic pollutants has drawn world-wide concern. Biotechnology has been applied for many years to the decontamination of soils polluted with organic and inorganic contaminants, and novel nanomaterials (NMs) has attracted much concern due to their high capacity for the removal/stabilization/degradation of pollutants. Recently, developing advanced biotechnology with NMs for the remediation of contaminated soils has become a hot research topic. Some researchers found that bioremediation efficiency of contaminated soils was enhanced by the addition of NMs, while others demonstrated that the toxicity of NMs to the organism negatively influenced the repair capacity of polluted soils. This paper reviews the application of biotechnology and NMs in soil remediation, and further provides a critical view of the effects of NMs on the phytoremediation and micro-remediation of contaminated soils. This review also discusses the future research needs for the combined application of biotechnology and NMs in soil remediation.

  13. [Mixture Leaching Remediation Technology of Arsenic Contaminated Soil].

    Science.gov (United States)

    Chen, Xun-feng; Li, Xiao-ming; Chen, Can; Yang, Qi; Deng, Lin-jing; Xie, Wei-qiang; Zhong, Yui; Huang, Bin; Yang, Wei-qiang; Zhang, Zhi-bei

    2016-03-15

    Soil contamination of arsenic pollution has become a severely environmental issue, while soil leaching is an efficient method for remediation of arsenic-contaminated soil. In this study, batch tests were primarily conducted to select optimal mixture leaching combination. Firstly, five conventional reagents were selected and combined with each other. Secondly, the fractions were analyzed before and after the tests. Finally, to explore the feasibility of mixed leaching, three soils with different arsenic pollution levels were used to compare the leaching effect. Comparing with one-step washing, the two-step sequential washing with different reagents increased the arsenic removal efficiency. These results showed that the mixture of 4 h 0.5 mol · L⁻¹ NaOH + 4 h 0.1 mol · L⁻¹ EDTA was found to be practicable, which could enhance the removal rate of arsenic from 66.67% to 91.83%, and the concentration of arsenic in soil was decreased from 186 mg · kg⁻¹ to 15.2 mg · kg⁻¹. Furthermore, the results indicated that the distribution of fractions of arsenic in soil changed apparently after mixture leaching. Leaching process could significantly reduce the available contents of arsenic in soil. Moreover, the mixture of 0.5 mol · L⁻¹ NaOH + 0.1 mol L⁻¹ EDTA could well decrease the arsenic concentration in aluminum-type soils, while the mixture of 0.5 mol · L⁻¹ OX + 0.5 mol · L⁻¹ NaOH could well decrease the arsenic concentration in iron-type soils.

  14. ELECTROCHEMICAL REMEDIATION TECHNOLOGIES (ECRTS) - IN SITU REMEDIATION OF CONTAMINATED MARINE SEDIMENTS

    Science.gov (United States)

    This Innovative Technology Evaulation Report summarizes the results of the evaluation of the Electrochemical Remediation Technologies (ECRTs) process, developed by P2-Soil Remediation, Inc. (in partnership with Weiss Associates and Electro-Petroleum, Inc.). This evaluation was co...

  15. A laboratory test of NOM-assisted remediation of arsenic and copper contaminated soils

    DEFF Research Database (Denmark)

    Rasmussen, Signe Bonde; Jensen, Julie Katrine; Borggaard, Ole K.

    2015-01-01

    Soils contaminated by arsenic (As) and copper (Cu) must be remediated because As and Cu are non-degradable and toxic. On moderately contaminated soils, As and Cu may be removed by in-situ plant uptake (phytoremediation), whereas strongly contaminated soils must be removed and cleaned by soil...

  16. COMBINATION OF A SOURCE REMOVAL REMEDY AND BIOREMEDIATION FOR THE TREATMENT OF A TCE CONTAMINATED AQUIFER

    Science.gov (United States)

    Historical disposal practices of chlorinated solvents have resulted in the widespread contamination of ground-water resources. These ground-water contaminants exist in the subsurface as free products, residual and vapor phases, and in solution. The remediation of these contamin...

  17. Uranium Contamination in the Subsurface Beneath the 300 Area, Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Robert E.; Rockhold, Mark L.; Serne, R. Jeffrey; Thorne, Paul D.; Williams, Mark D.

    2008-02-29

    This report provides a description of uranium contamination in the subsurface at the Hanford Site's 300 Area. The principal focus is a persistence plume in groundwater, which has not attenuated as predicted by earlier remedial investigations. Included in the report are chapters on current conditions, hydrogeologic framework, groundwater flow modeling, and geochemical considerations. The report is intended to describe what is known or inferred about the uranium contamination for the purpose of making remedial action decisions.

  18. Phase I remedial investigation report of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D.E. [ed.

    1995-07-01

    This report presents the activities and findings of the first phase of a three-phase remedial investigation (RI) of Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, and updates the scope and strategy for WAG-2-related efforts. WAG 2 contains White Oak Creek (WOC) and its tributaries downstream of the ORNL main plant area, White Oak Lake, White Oak Creek Embayment on the Clinch River, and the associated floodplain and subsurface environment. Water, sediment, soil, and biota in WAG 2 are contaminated and continue to receive contaminants from upgradient WAGs. This report includes field activities completed through October 1992. The remediation of WAG 2 is scheduled to follow the cessation of contaminant input from hydrologically upgradient WAGs. While upgradient areas are being remediated, the strategy for WAG 2 is to conduct a long-term monitoring and investigation program that takes full advantage of WAG 2`s role as an integrator of contaminant fluxes from other ORNL WAGs and focuses on four key goals: (1) Implement, in concert with other programs, long-term, multimedia environmental monitoring and tracking of contaminants leaving other WAGs, entering WAG 2, and being transported off-site. (2) Provide a conceptual framework to integrate and develop information at the watershed-level for pathways and processes that are key to contaminant movement, and so support remedial efforts at ORNL. (3) Provide periodic updates of estimates of potential risk (both human health and ecological) associated with contaminants accumulating in and moving through WAG 2 to off-site areas. (4) Support the ORNL Environmental Restoration Program efforts to prioritize, remediate, and verify remedial effectiveness for contaminated sites at ORNL, through long-term monitoring and continually updated risk assessments.

  19. Phase I remedial investigation report of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D.E. [ed.

    1995-07-01

    This report presents the activities and findings of the first phase of a three-phase remedial investigation (RI) of Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, and updates the scope and strategy for WAG-2-related efforts. WAG 2 contains White Oak Creek (WOC) and its tributaries downstream of the ORNL main plant area, White Oak Lake, White Oak Creek Embayment on the Clinch River, and the associated floodplain and subsurface environment. Water, sediment, soil, and biota in WAG 2 are contaminated and continue to receive contaminants from upgradient WAGs. This report includes field activities completed through October 1992. The remediation of WAG 2 is scheduled to follow the cessation of contaminant input from hydrologically upgradient WAGs. While upgradient areas are being remediated, the strategy for WAG 2 is to conduct a long-term monitoring and investigation program that takes full advantage of WAG 2`s role as an integrator of contaminant fluxes from other ORNL WAGs and focuses on four key goals: (1) Implement, in concert with other programs, long-term, multimedia environmental monitoring and tracking of contaminants leaving other WAGs, entering WAG 2, and being transported off-site. (2) Provide a conceptual framework to integrate and develop information at the watershed-level for pathways and processes that are key to contaminant movement, and so support remedial efforts at ORNL. (3) Provide periodic updates of estimates of potential risk (both human health and ecological) associated with contaminants accumulating in and moving through WAG 2 to off-site areas. (4) Support the ORNL Environmental Restoration Program efforts to prioritize, remediate, and verify remedial effectiveness for contaminated sites at ORNL, through long-term monitoring and continually updated risk assessments.

  20. Remediation Measures for Posta Rât Contaminated Site (Turda

    Directory of Open Access Journals (Sweden)

    SIMULE Codruţa Violeta

    2010-08-01

    Full Text Available Waste (in the form of isomers of hexachlorocyclohexane - HCH resulting from the fabrication process oflindane of the former UCT - Turda Chemical Plants were stored, from 1954 to 1983, in 4 uncontrolled settlements fromthe Turda area, one of which is the settlement from the Posta Rât. Posta Rât contaminated site occupies an area of 4hectares, outside the built-up area of the Turda Municipality, on the left side of Aries River, summing up a quantity ofapproximately 18 500 tons of waste mixed with soil. As a result of uncontrolled storage activities, the water, air, soiland biodiversity were affected. Due to the strong negative influence of this historically contaminated site, in thismaterial our attention focuses on environmental impact assessment and identifies the most appropriate measures for thesite rehabilitation in order to restore soil functions. Based on the soil and groundwater analysis, the following measureswere proposed in order to ensure human health and environmental protection: on-site treatment of contaminated soiland groundwater, laying clean vegetal ground throughout the entire surface and replanting the retrieved land’s surfacewith trees. To ensure the success of rehabilitation action is required to install a ground water monitoring network andcarrying out a monitoring plan.

  1. Remediation of soil contaminated with pyrene using ground nanoscale zero-valent iron

    Energy Technology Data Exchange (ETDEWEB)

    Ming-Chin Chang; Hung-Yee Shu; Wen-Pin Hsieh; Min-Chao Wang [Hungkuang University, Taichung (China). Department of Environmental Engineering

    2007-02-15

    The sites contaminated with recalcitrant polycyclic aromatic hydrocarbons (PAHs) are serious environmental problems ubiquitously. Some PAHs have proven to be carcinogenic and hazardous. Therefore, the innovative PAH in situ remediation technologies have to be developed instantaneously. Recently, the nanoscale zero-valent iron (ZVI) particles have been successfully applied for dechlorination of organic pollutants in water, yet little research has investigated for the soil remediation so far. The objective in this work was to take advantage of nanoscale ZVI particles to remove PAHs in soil. The experimental factors such as reaction time, particle diameter and iron dosage and surface area were considered and optimized. From the results, both microscale and nanoscale ZVI were capable to remove the target compound. The higher removal efficiencies of nanoscale ZVI particles were obtained because the specific surface areas were about several dozens larger than that of commercially microscale ZVI particles. The optimal parameters were observed as 0.2 g iron/2 mL water in 60 min and 150 rpm by nanoscale ZVI. Additionally, the results proved that nanoscale ZVI particles are a promising technology for soil remediation and are encouraged in the near future environmental applications. Additionally, the empirical equation developed for pyrene removal efficiency provided the good explanation of reaction behavior. Ultimately, the calculated values by this equation were in a good agreement with the experimental data. 19 refs., 9 figs., 2 tabs.

  2. Remediation and its effect represented on long term monitoring data at a chlorinated ethenes contaminated site, Wonju, Korea

    Science.gov (United States)

    Lee, Seong-Sun; Lee, Seung Hyun; Lee, Kang-Kun

    2016-04-01

    A research for the contamination of chlorinated ethenes such as trichloroethylene (TCE) at an industrial complex, Wonju, Korea, was carried out based on 17 rounds of groundwater quality data collection from 2009 to 2015. Remediation technologies such as soil vapor extraction, soil flushing, biostimulation, and pump-and-treat have been applied to eliminate the contaminant sources of trichloroethylene (TCE) and to prevent the migration of TCE plume from remediation target zones to groundwater discharge area like a stream. The remediation efficiency according to the remedial actions was evaluated by tracing a time-series of plume evaluation and temporal mass discharge at three transects (Source, Transect-1, Transect-2) which was assigned along the groundwater flow path. Also, based on long term monitoring data, dissolved TCE concentration and mass of residual TCE in the initial stage of disposal were estimated to evaluate the efficiency of in situ remediation. The results of temporal and spatial monitoring before remedial actions showed that a TCE plume originating from main and local source zones continues to be discharged to a stream. However, from the end of intensive remedial actions from 2012 to 2013, the aqueous concentrations of TCE plume present at and around the main source areas decreased significantly. Especially, during the intensive remediation period, the early average mass discharge (26.58 g/day) at source transect was decreased to average 4.99 g/day. Estimated initial dissolved concentration and residual mass of TCE in the initial stage of disposal decreased rapidly after an intensive remedial action in 2013 and it is expected to be continuously decreased from the end of remedial actions to 2020. This study demonstrates that long term monitoring data are useful in assessing the effectiveness of remedial actions at chlorinated ethenes contaminated site. Acknowledgements This project is supported by the Korea Ministry of Environment under "The GAIA

  3. Remediation of Deep Vadose Zone Radionuclide and Metal Contamination: Status and Issues

    Energy Technology Data Exchange (ETDEWEB)

    Dresel, P. Evan; Truex, Michael J.; Cantrell, Keri

    2008-12-30

    This report documents the results of a PNNL literature review to report on the state of maturity of deep vadose zone remediation technologies for metal contaminants including some radionuclides. Its recommendations feed into decisionmakers need for scientific information and cost-effective in situ remediation technlogies needed under DOE's Environmental Management initiative Enhanced Remediation Methods: Scientific & Technical Basis for In Stu Treatment Systems for Metals and Radionuclides.

  4. Remediation of trichloroethylene-contaminated soils by star technology using vegetable oil smoldering

    OpenAIRE

    Salman, Madiha; Gerhard, Jason I.; Major, David W.; Pironi, Paolo; Hadden, Rory

    2015-01-01

    Self-sustaining treatment for active remediation (STAR) is an innovative soil remediation approach based on smoldering combustion that has been demonstrated to effectively destroy complex hydrocarbon nonaqueous phase liquids (NAPLs) with minimal energy input. This is the first study to explore the smoldering remediation of sand contaminated by a volatile NAPL (trichloroethylene, TCE) and the first to consider utilizing vegetable oil as supplemental fuel for STAR. Thirty laboratory-scale exper...

  5. Effects of different remediation treatments on crude oil contaminated saline soil.

    Science.gov (United States)

    Gao, Yong-Chao; Guo, Shu-Hai; Wang, Jia-Ning; Li, Dan; Wang, Hui; Zeng, De-Hui

    2014-12-01

    Remediation of the petroleum contaminated soil is essential to maintain the sustainable development of soil ecosystem. Bioremediation using microorganisms and plants is a promising method for the degradation of crude oil contaminants. The effects of different remediation treatments, including nitrogen addition, Suaeda salsa planting, and arbuscular mycorrhiza (AM) fungi inoculation individually or combined, on crude oil contaminated saline soil were assessed using a microcosm experiment. The results showed that different remediation treatments significantly affected the physicochemical properties, oil contaminant degradation and bacterial community structure of the oil contaminated saline soil. Nitrogen addition stimulated the degradation of total petroleum hydrocarbon significantly at the initial 30d of remediation. Coupling of different remediation techniques was more effective in degrading crude oil contaminants. Applications of nitrogen, AM fungi and their combination enhanced the phytoremediation efficiency of S. salsa significantly. The main bacterial community composition in the crude oil contaminated saline soil shifted with the remediation processes. γ-Proteobacteria, β-Proteobacteria, and Actinobacteria were the pioneer oil-degraders at the initial stage, and Firmicutes were considered to be able to degrade the recalcitrant components at the later stage.

  6. Modeling the effects and uncertainties of contaminated sediment remediation scenarios in a Norwegian fjord by Markov chain Monte Carlo simulation.

    Science.gov (United States)

    Saloranta, Tuomo M; Armitage, James M; Haario, Heikki; Naes, Kristoffer; Cousins, Ian T; Barton, David N

    2008-01-01

    Multimedia environmental fate models are useful tools to investigate the long-term impacts of remediation measures designed to alleviate potential ecological and human health concerns in contaminated areas. Estimating and communicating the uncertainties associated with the model simulations is a critical task for demonstrating the transparency and reliability of the results. The Extended Fourier Amplitude Sensitivity Test(Extended FAST) method for sensitivity analysis and Bayesian Markov chain Monte Carlo (MCMC) method for uncertainty analysis and model calibration have several advantages over methods typically applied for multimedia environmental fate models. Most importantly, the simulation results and their uncertainties can be anchored to the available observations and their uncertainties. We apply these techniques for simulating the historical fate of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the Grenland fjords, Norway, and for predicting the effects of different contaminated sediment remediation (capping) scenarios on the future levels of PCDD/Fs in cod and crab therein. The remediation scenario simulations show that a significant remediation effect can first be seen when significant portions of the contaminated sediment areas are cleaned up, and that increase in capping area leads to both earlier achievement of good fjord status and narrower uncertainty in the predicted timing for this.

  7. Public perceptions of a radioactively contaminated site: concerns, remediation preferences, and desired involvement.

    Science.gov (United States)

    Feldman, D L; Hanahan, R A

    1996-12-01

    A public attitudes survey was conducted in neighborhoods adjacent to a radioactively contaminated site whose remediation is now under the auspices of the U.S. Department of Energy's Formerly Utilized Sites Remedial Action Program (FUSRAP). The survey's purpose was to ascertain levels of actual and desired public involvement in the remediation process; to identify health, environmental, economic, and future land-use concerns associated with the site; and to solicit remediation strategy preferences. Surface water and groundwater contamination, desire for public involvement, and potential health risks were found to be the most highly ranked site concerns. Preferred remediation strategies included treatment of contaminated soil and excavation with off-site disposal. Among on-site remediation strategies, only institutional controls that leave the site undisturbed and do not require additional excavation of materials were viewed favorably. Cost of remediation appeared to influence remediation strategy preference; however, no strategy was viewed as a panacea. Respondents were also concerned with protecting future generations, better assessment of risks to health and the environment, and avoiding generation of additional contaminated materials.

  8. Engineering Issue: Technology Alternatives for the Remediation of PCB Contaminated Soils and Sediments

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) Engineering Issue papers are a series of documents that summarize the available information on specific contaminates, selected treatment and site remediation technologies, and related issues. This Engineering Issue paper is intended...

  9. Modified endophytes for improving phyto remediation and mixed contaminations of heavy metals (Ni) and organic contaminants (Toluene)

    Energy Technology Data Exchange (ETDEWEB)

    Weyens, N.; Barac, T.; Lelie, D. van der; Taghavi, S.; Vangronsveld, J.

    2009-07-01

    Phytoremediation is a promising technology for the remediation of soils and groundwater contaminated with heavy metals and organic pollutants. However, large-scale application of phytoremediation faces a number of obstacles including the levels of pollutants tolerated by the plant, the bioavailability of the contaminants and, in some cases, the evapotranspiration of volatile organic pollutants. (Author)

  10. LCA of contaminated site remediation - integration of site-specific impact assessment of local toxic impacts

    DEFF Research Database (Denmark)

    Lemming, Gitte; Hauschild, Michael Zwicky; Chambon, Julie Claire Claudia

    2011-01-01

    The environmental impacts from remediation can be divided into primary and secondary impacts. Primary impacts cover the local impacts associated with the on-site contamination, whereas the secondary impacts are impacts on the local, regional and global scale generated by the remediation activities...... impacts have typically been assessed using site-generic characterization models representing a continental scale and excluding the groundwater compartment. Soil contaminants have therefore generally been assigned as emissions to surface soil or surface water compartments. However, such site...

  11. State of the Science Review: Potential for Beneficial Use of Waste By-Products for In-situ Remediation of Metal-Contaminated Soil and Sediment

    Science.gov (United States)

    Metal and metalloid contamination of soil and sediment is a widespread problem both in urban and rural areas throughout the United States (U.S. EPA, 2014). Beneficial use of waste by-products as amendments to remediate metal-contaminated soils and sediments can provide major eco...

  12. REMEDIATION OF NITRATE-CONTAMINATED GROUNDWATER USING A BIOBARRIER

    Energy Technology Data Exchange (ETDEWEB)

    B. STRIETELMEIER; M. ESPINOSA

    2001-01-01

    A biobarrier system has been developed for use in remediating shallow alluvial groundwater. This barrier is made from highly porous materials that are relatively long-lasting, carbon-based (to supply a limiting nutrient in nitrate destruction, in most cases), extremely inexpensive, and easy to replace. In a series of laboratory studies, we have determined the effectiveness of this barrier at destroying nitrate and perchlorate in groundwater from Mortandad Canyon at Los Alamos National Laboratory (LANL). This groundwater was obtained from a monitoring well, MCO-5, which is located in the flowpath of the discharge waters from the LANL Radioactive Liquid Waste Treatment Facility (RLWTF). Water with elevated nitrate levels was discharged from this plant for many years. Recently, the nitrate levels have been brought under the discharge limits. However, the historical discharge has resulted in a nitrate plume in the alluvial groundwater in this canyon. The LANL Multi-Barrier project was initiated in 1999 to develop a system of barriers that would prevent the transport of radionuclides, metals, colloids and other contaminants, including nitrate and perchlorate, further down the canyon in order to protect populations down-gradient. The biobarrier will be part of this Multi-Barrier system. We have demonstrated the destruction of nitrate at levels up to 6.5-9.7 mM nitrate (400-600 mg/L), and that of perchlorate at levels of about 4.3 {micro}M perchlorate (350 ppb). We have quantified the populations of microorganisms present in the biofilm that develops on the biobarrier. The results of this research will be discussed along with other potential applications of this system.

  13. REMEDIATION OF NITRATE-CONTAMINATED GROUNDWATER USING A BIOBARRIER

    Energy Technology Data Exchange (ETDEWEB)

    B. STRIETELMEIR; ET AL

    2000-12-01

    A biobarrier system has been developed for use in remediating shallow alluvial groundwater. This barrier is made from highly porous materials that are relatively long-lasting, carbon-based (to supply a limiting nutrient in nitrate destruction, in most cases), and extremely inexpensive and easy to emplace. In a series of laboratory studies, we have determined the effectiveness of this barrier at destroying nitrate and perchlorate in groundwater from Mortandad Canyon at Los Alamos National Laboratory (LANL). This groundwater was obtained from a monitoring well, MCO-5, which is located in the flowpath of the discharge waters from the LANL Radioactive Liquid Waste Treatment Facility (RLWTF). Water with elevated nitrate levels has been discharged from this plant for many years, until recently when the nitrate levels have been brought under the discharge limits. However, the historical discharge has resulted in a nitrate plume in the alluvial groundwater in this canyon. The LANL Multi-Barrier project was initiated this past year to develop a system of barriers that would prevent the transport of radionuclides, metals, colloids and other contaminants, including nitrate and perchlorate, further down the canyon in order to protect populations down-gradient. The biobarrier. will be part of this Multi-Barrier system. We have demonstrated the destruction of nitrate at levels up to 6.5-9.7 mhl nitrate (400-600 mg/L), and that of perchlorate at levels of about 4.3 {micro}M perchlorate (350 ppb). We have quantified the populations of microorganisms present in the biofilm that develops on the biobarrier. The results of this research will be discussed along with other potential applications of this system.

  14. Remedy Evaluation Framework for Inorganic, Non-Volatile Contaminants in the Vadose Zone

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J.; Carroll, Kenneth C.

    2013-05-01

    Contaminants in the vadose zone may act as a potential long-term source of groundwater contamination and need to be considered in remedy evaluations. In many cases, remediation decisions for the vadose zone will need to be made all or in part based on projected impacts to groundwater. Because there are significant natural attenuation processes inherent in vadose zone contaminant transport, remediation in the vadose zone to protect groundwater is functionally a combination of natural attenuation and use of other remediation techniques, as needed, to mitigate contaminant flux to groundwater. Attenuation processes include both hydrobiogeochemical processes that serve to retain contaminants within porous media and physical processes that mitigate the rate of water flux. In particular, the physical processes controlling fluid flow in the vadose zone are quite different and generally have a more significant attenuation impact on contaminant transport relative to those within the groundwater system. A remedy evaluation framework is presented herein that uses an adaptation of the established EPA Monitored Natural Attenuation (MNA) evaluation approach and a conceptual model based approach focused on identifying and quantifying features and processes that control contaminant flux through the vadose zone. A key concept for this framework is to recognize that MNA will comprise some portion of all remedies in the vadose zone. Thus, structuring evaluation of vadose zone waste sites to use an MNA-based approach provides information necessary to either select MNA as the remedy, if appropriate, or to quantify how much additional attenuation would need to be induced by a remedial action (e.g., technologies considered in a feasibility study) to augment the natural attenuation processes and meet groundwater protection goals.

  15. Geological characterization and solute transport model investigations of contaminated sites in urban areas (Denmark)

    DEFF Research Database (Denmark)

    Andersen, Theis Raaschou; Poulsen, Søren Erbs; Thomsen, Peter

    2015-01-01

    . Remediation is time consuming and expensive and it is often difficult to identify the original source of the contamination that would otherwise give indications to its extent and composition. Moreover, as cities grew, many contaminations are now located in urban areas where data compilation and remediation...... efforts are often challenged by logistics. The general lack of knowledge about theses contaminations introduces significant uncertainties in the projections on the fate of the contaminant. We carry out a geological characterization of two contaminated sites situated in urban areas. The existing data from...... of the two sites were constructed. The 3D geological models serve as a basis for simulating groundwater flow and contaminant transport at the field sites. The study demonstrates how detailed information about the geological setting in conjunction with contaminant transport modelling, can minimize...

  16. In situ Remediation of Petroleum Contaminated Groundwater by Permeable Reactive Barrier with Hydrothermal Palygorskite as Medium

    Institute of Scientific and Technical Information of China (English)

    ZHANG Sheng-yu; ZHANG Yu-ling; SU Xiao-si; ZHANG Ying

    2013-01-01

    The permeable reactive barrier(PRB) has proven to be a cost-effective technique to remediate the petroleum contaminated groundwater at a northeast field site in China.In this study,the geology,hydrogeology and contamination characterization of the field site were investigated and the natural hydrothermal palygorskite was chosen as a reactive medium.Furthermore,the adsorption of the total petroleum hydrocarbons(TPH) in the groundwater onto hydrothermal palygorskite and the adsorption kinetics were investigated.The results indicate that the removal rates of TPH,benzene,naphthalene and phenantharene could all reach up to 90% by hydrothermal palygorskite with a diameter of 0.25-2.00 mm that had been thermally pretreated at 140 ℃.The adsorption of TPH onto hydrothermal palygorskite after pretreatment followed a pseudo-second-order kinetic model and a Langmuir adsorption isotherm,suggesting that the theoretic adsorption capacity of hydrothermal palygorskite for adsorbate could be 4.2 g/g.Scanning electron microscopy(SEM),infrared spectroscopy(IR),X-ray diffraction(XRD) and X-ray fluorescence spectroscopy(XRF) were carried out to analyze the adsorption mechanism.The results reveal that hydrothermal palygorskite is a fibrous silicate mineral enriched in Mg and A1 with large surface area and porosity.The dense cluster acicular and fibrous crystal of hydrothermal palygorskite,and its effect polar group —OH played an important role in the physical and chemical adsorption processes of it for contaminants.This study has demonstrated hydrothermal palygorskite is a reliable reactive medium for in situ remediation of petroleum contaminated groundwater at field sites.

  17. 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

  18. Remediation of Groundwater Contaminated with Organics and Radionuclides - An Innovative Approach Eases Traditional Hurdles

    Energy Technology Data Exchange (ETDEWEB)

    Scott, J.; Case, N.; Coltman, K.

    2003-02-25

    Traditional approaches to the remediation of contaminated groundwater, such as pump-and-treat, have been used for many years for the treatment of groundwater contaminated with various organics. However the treatment of groundwater contaminated with organics and radionuclides has been considerably more challenging. Safety and Ecology Corporation (SEC) was recently faced with these challenges while designing a remediation system for the remediation of TCE-contaminated groundwater and soil at the RMI Extrusion Plant in Ashtabula, OH. Under contract with RMI Environmental Services (RMIES), SEC teamed with Regenesis, Inc. to design, implement, and execute a bioremediation system to remove TCE and associated organics from groundwater and soil that was also contaminated with uranium and technetium. The SEC-Regenesis system involved the injection of Hydrogen Release Compound (HRC), a natural attenuation accelerant that has been patented, designed, and produced by Regenesis, to stimulate the reductive dechlorination and remediation of chlorinated organics in subsurface environments. The compound was injected using direct-push Geoprobe rods over a specially designed grid system through the zone of contaminated groundwater. The innovative approach eliminated the need to extract contaminated groundwater and bypassed the restrictive limitations listed above. The system has been in operation for roughly six months and has begun to show considerable success at dechlorinating and remediating the TCE plume and in reducing the radionuclides into insoluble precipitants. The paper will provide an overview of the design, installation, and initial operation phase of the project, focusing on how traditional design challenges of remediating radiologically contaminated groundwater were overcome. The following topics will be specifically covered: a description of the mechanics of the HRC technology; an assessment of the applicability of the HRC technology to contaminated groundwater plumes

  19. Engineering and environmental remediation scenarios due to leakage from the Gulf War oil spill using 3-D numerical contaminant modellings

    Science.gov (United States)

    Yihdego, Yohannes; Al-Weshah, Radwan A.

    2016-12-01

    The transport groundwater modelling has been undertaken to assess potential remediation scenarios and provide an optimal remediation options for consideration. The purpose of the study was to allow 50 years of predictive remediation simulation time. The results depict the likely total petroleum hydrocarbon migration pattern in the area under the worst-case scenario. The remediation scenario simulations indicate that do nothing approach will likely not achieve the target water quality within 50 years. Similarly, complete source removal approach will also likely not achieve the target water quality within 50 years. Partial source removal could be expected to remove a significant portion of the contaminant mass, but would increase the rate of contaminant recharge in the short to medium term. The pump-treat-reinject simulation indicates that the option appears feasible and could achieve a reduction in the area of the 0.01 mg/L TPH contour area for both Raudhatain and Umm Al-Aish by 35 and 30%, respectively, within 50 years. The rate of improvement and the completion date would depend on a range of factors such as bore field arrangements, pumping rates, reinjection water quality and additional volumes being introduced and require further optimisation and field pilot trials.

  20. Radioactive Tank Waste Remediation Focus Area. Technology summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    In February 1991, DOE`s Office of Technology Development created the Underground Storage Tank Integrated Demonstration (UST-ID), to develop technologies for tank remediation. Tank remediation across the DOE Complex has been driven by Federal Facility Compliance Agreements with individual sites. In 1994, the DOE Office of Environmental Management created the High Level Waste Tank Remediation Focus Area (TFA; of which UST-ID is now a part) to better integrate and coordinate tank waste remediation technology development efforts. The mission of both organizations is the same: to focus the development, testing, and evaluation of remediation technologies within a system architecture to characterize, retrieve, treat, concentrate, and dispose of radioactive waste stored in USTs at DOE facilities. The ultimate goal is to provide safe and cost-effective solutions that are acceptable to both the public and regulators. The TFA has focused on four DOE locations: the Hanford Site in Richland, Washington, the Idaho National Engineering Laboratory (INEL) near Idaho Falls, Idaho, the Oak Ridge Reservation in Oak Ridge, Tennessee, and the Savannah River Site (SRS) in Aiken, South Carolina.

  1. Arrangements for Radiation Protection of Remediation Workers in Off-site Contaminated Areas at the Fukushima Daiichi NPP%福岛核事故场外污染整治中工作人员的辐射防护应对

    Institute of Scientific and Technical Information of China (English)

    王旭东

    2014-01-01

    An overview of Ordinance on Prevention of Ionizing Radiation Hazards at Works to Decontaminate Soil and Wastes Contaminated by Radioactive Materials Resulting from the Great East Japan Earthquake and Related Works presented ,along with the relevant guidelines .Their implementation in Fukushima Prefecture in the year of 2013 is also summarized .It seems that efforts of Japan to cope with radiation protection of remedi-ation workers in contaminated areas off-site are far from having been turned into good practices .%简要介绍了《东日本大地震致放射性污染土壤与废物清理及相关作业中电离辐射危害防止条例》和相关导则,以及2013年间福岛县的相应监管状况,粗略呈现出福岛核事故后日本在应对场外污染整治工作人员辐射防护之需求方面的努力,亦说明今后更多地需要在整治作业实践中予以落实。

  2. Guidelines for active spreading during in situ chemical oxidation to remediate contaminated groundwater

    Science.gov (United States)

    The effectiveness of in situ chemical oxidation to remediate contaminated aquifers depends on the extent and duration of contact between the injected treatment chemical and the groundwater contaminant (the reactants). Techniques that inject and extract in the aquifer to ‘ac...

  3. Remediation of radiocesium-contaminated liquid waste, soil, and ash: a mini review since the Fukushima Daiichi Nuclear Power Plant accident.

    Science.gov (United States)

    Ding, Dahu; Zhang, Zhenya; Lei, Zhongfang; Yang, Yingnan; Cai, Tianming

    2016-02-01

    The radiation contamination after the Fukushima Daiichi Nuclear Power Plant accident attracts considerable concern all over the world. Many countries, areas, and oceans are greatly affected by the emergency situation other than Japan. An effective remediation strategy is in a highly urgent demand. Though plenty of works have been carried out, progressive achievements have not yet been well summarized. Here, we review the recent advances on the remediation of radiocesium-contaminated liquid waste, soil, and ash. The overview of the radiation contamination is firstly given. Afterwards, the current remediation strategies are critically reviewed in terms of the environmental medium. Special attentions are paid on the adsorption/ion exchange and electrically switched ion exchange methods. Finally, the present review outlines the possible works to do for the large-scale application of the novel remediation strategies.

  4. 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

  5. Some Case Studies on Metal-Microbe Interactions to Remediate Heavy Metals- Contaminated Soils in Korea

    Science.gov (United States)

    Chon, Hyo-Taek

    2015-04-01

    Conventional physicochemical technologies to remediate heavy metals-contaminated soil have many problems such as low efficiency, high cost and occurrence of byproducts. Recently bioremediation technology is getting more and more attention. Bioremediation is defined as the use of biological methods to remediate and/or restore the contaminated land. The objectives of bioremediation are to degrade hazardous organic contaminants and to convert hazardous inorganic contaminants to less toxic compounds of safe levels. The use of bioremediation in the treatment of heavy metals in soils is a relatively new concept. Bioremediation using microbes has been developed to remove toxic heavy metals from contaminated soils in laboratory scale to the contaminated field sites. Recently the application of cost-effective and environment-friendly bioremediation technology to the heavy metals-contaminated sites has been gradually realized in Korea. The merits of bioremediation include low cost, natural process, minimal exposure to the contaminants, and minimum amount of equipment. The limitations of bioremediation are length of remediation, long monitoring time, and, sometimes, toxicity of byproducts for especially organic contaminants. From now on, it is necessary to prove applicability of the technologies to contaminated sites and to establish highly effective, low-cost and easy bioremediation technology. Four categories of metal-microbe interactions are generally biosorption, bioreduction, biomineralization and bioleaching. In this paper, some case studies of the above metal-microbe interactions in author's lab which were published recently in domestic and international journals will be introduced and summarized.

  6. Contaminated soil remediation and quality assurance; Pilaantuneen maan kunnostaminen ja laadunvarmistus

    Energy Technology Data Exchange (ETDEWEB)

    Sarkkila, J.; Mroueh, U.M.; Leino-Forsman, H.

    2004-07-01

    The aim of contaminated soil remediation quality assurance is to carry out remediation activities according to plans. Besides the design work the appropriate implementation of the quality assurance covers source data and investigation methods as well as the requirements for documentation. Contaminated soil characterization and the selection of the most suitable remediation method is made with the help of various sampling and analysis methods. There are different kinds of requirements to the sampling plan depending on the type of remediation project. Quality assurance is taken into account in sampling, in sample handling and analysis as well as in the reporting of results. The most common unsaturated zone remediation methods used in Finland are introduced in this guide. These methods include excavation (as part of remediation), encapsulating, stabilization, thermal desorption, soil washing, composting, soil vapor extraction and bioventing. The methods are introduced on a general level with emphasis on their technical implementation and feasibility as well as on the eventual material requirements. Harmful environmental impacts of the methods must be identified and prevented. In order to monitor the remediation process, various chemical and physical quality assurance measurements are performed. Additionally the work safety issues related to remediation methods must be taken into account and proper documentation must be prepared. (orig.)

  7. Remediation approaches for polycyclic aromatic hydrocarbons (PAHs) contaminated soils: Technological constraints, emerging trends and future directions.

    Science.gov (United States)

    Kuppusamy, Saranya; Thavamani, Palanisami; Venkateswarlu, Kadiyala; Lee, Yong Bok; Naidu, Ravi; Megharaj, Mallavarapu

    2017-02-01

    For more than a decade, the primary focus of environmental experts has been to adopt risk-based management approaches to cleanup PAH polluted sites that pose potentially destructive ecological consequences. This focus had led to the development of several physical, chemical, thermal and biological technologies that are widely implementable. Established remedial options available for treating PAH contaminated soils are incineration, thermal conduction, solvent extraction/soil washing, chemical oxidation, bioaugmentation, biostimulation, phytoremediation, composting/biopiles and bioreactors. Integrating physico-chemical and biological technologies is also widely practiced for better cleanup of PAH contaminated soils. Electrokinetic remediation, vermiremediation and biocatalyst assisted remediation are still at the development stage. Though several treatment methods to remediate PAH polluted soils currently exist, a comprehensive overview of all the available remediation technologies to date is necessary so that the right technology for field-level success is chosen. The objective of this review is to provide a critical overview in this respect, focusing only on the treatment options available for field soils and ignoring the spiked ones. The authors also propose the development of novel multifunctional green and sustainable systems like mixed cell culture system, biosurfactant flushing, transgenic approaches and nanoremediation in order to overcome the existing soil- contaminant- and microbial-associated technological limitations in tackling high molecular weight PAHs. The ultimate objective is to ensure the successful remediation of long-term PAH contaminated soils.

  8. Synthetic humic substances and their use for remediation of contaminated environments

    Science.gov (United States)

    Dudare, Diana; Klavins, Maris

    2014-05-01

    ions, which were reflected in their complexation properties towards metal ions. FTIR spectra gave evidence of the presence of metal ions, strongly bound and protected in inner sphere complexes. Considering a large scale of production of humic substances, the obtained synthetic humic substances with modified properties are perspective and sustainable areas of use. The obtained results of this study showed that synthetic humic substances can be used for remediation of environments contaminated with heavy metal ions.

  9. The role of cell bioaugmentation and gene bioaugmentation in the remediation of co-contaminated soils.

    OpenAIRE

    Pepper, Ian L.; Gentry, Terry J; Newby, Deborah T; Roane, Timberley M; Josephson, Karen L.

    2002-01-01

    Soils co-contaminated with metals and organics present special problems for remediation. Metal contamination can delay or inhibit microbial degradation of organic pollutants such that for effective in situ biodegradation, bioaugmentation is necessary. We monitored the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) or 3-chlorobenzoate (3-CB) in two different soils with and without cadmium (Cd) contamination. Additionally, we evaluated the ability of bioaugmentation to enhance organic de...

  10. The norms, rules and motivational values driving sustainable remediation of contaminated environments: A study of implementation.

    Science.gov (United States)

    Prior, Jason

    2016-02-15

    Efforts to achieve sustainability are transforming the norms, rules and values that affect the remediation of contaminated environments. This is altering the ways in which remediation impacts on the total environment. Despite this transformation, few studies have provided systematic insights into the diverse norms and rules that drive the implementation of sustainable remediation at contaminated sites, and no studies have investigated how values motivate compliance with these norms and rules. This study is a systematic analysis of the rules, norms and motivational values embedded in sustainable remediation processes at three sites across Australia, using in-depth interviews conducted with 18 participants between 2011 and 2014, through the application of Crawford and Ostrom's Institutional Grammar and Schwartz's value framework. These approaches offered methods for identifying the rules, norms, and motivational values that guided participants' actions within remediation processes at these sites. The findings identify a core set of 16 norms and 18 rules (sanctions) used by participants to implement sustainable remediation at the sites. These norms and rules: define the position of participants within the process, provide means for incorporating sustainability into established remediation practices, and define the scope of outcomes that constitute sustainable remediation. The findings revealed that motivational values focused on public interest and self-interest influenced participants' compliance with norms and rules. The findings also found strong interdependence between the norms and rules (sanctions) within the remediation processes and the normative principles operating within the broader domain of environmental management and planning. The paper concludes with a discussion of: the system of norms operating within sustainable remediation (which far exceed those associated with ESD); their link, through rules (sanctions) to contemporary styles of regulatory

  11. Physicochemical and microbiological effects of biosurfactant on the remediation of HOC-contaminated soil

    Institute of Scientific and Technical Information of China (English)

    ZENG Guangming; ZHONG Hua; HUANG Guohe; FU Haiyan

    2005-01-01

    Remediation of soil contaminated by hydrophobic organic compounds using biosurfactants as additives involves interactions between soil matrix, hydrophobic organic compound contaminants, biosurfactants and microorganisms. In this paper, the mechanism for biosurfactants to enhance the contaminant degradation is basically revealed. Biosurfactants can enhance solubilization of the contaminants in the soil matrix, change their mass transfer properties into the aqueous phase, as well as affect their sorption properties. Furthermore, biosurfactants can act on microorganisms and change their surface properties, accordingly cause new growth and uptake behavior of the bacteria in the soil matrix. Both the physicochemical and the microbiological effects can basically increase the bioavailability of the contaminants and enhance their degradation.

  12. Electrodialytic Remediation of Pb Contaminated Soil - Effects of Soil Properties and Pb Distribution

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Jensen, Pernille Erland

    1999-01-01

    The aim of this work was to investigate the effects of soil properties and Pb distribution on the electrodialytic remediation of Pb contaminated soil. Two naturally Pb contaminated soils were compared with respect to total Pb content, Pb distribution, pH, carbonate content, clay content and organic...... matter, and an electrodialytic remediation experiment was made on each soil.It was concluded that soil pH was the most important factor limiting the mobilisation of Pb. In one of the remediation experiments it was possible to mobilise and reduce the amount of Pb significantly, whereas in the other only...... a small amount of the initial Pb was mobilised at similar experimental conditions. A high buffering capacity of one of the soils, which was partly due to a high carbonate content, led to a bad remediation result....

  13. Effects of remediation train sequence on decontamination of heavy metal-contaminated soil containing mercury.

    Science.gov (United States)

    Hseu, Zeng-Yei; Huang, Yu-Tuan; Hsi, Hsing-Cheng

    2014-09-01

    When a contaminated site contains pollutants including both nonvolatile metals and Hg, one single remediation technology may not satisfactorily remove all contaminants. Therefore, in this study, chemical extraction and thermal treatment were combined as a remediation train to remove heavy metals, including Hg, from contaminated soil. A 0.2 M solution of ethylenediamine tetraacetic acid (EDTA) was shown to be the most effective reagent for extraction of considerable amounts of Cu, Pb, and Zn (> 50%). Hg removal was ineffective using 0.2 M EDTA, but thermogravimetric analysis suggested that heating to 550 degrees C with a heating rate of 5 degrees C/min for a duration of 1 hr appeared to be an effective approach for Hg removal. With the employment of thermal treatment, up to 99% of Hg could be removed. However executing thermal treatment prior to chemical extraction reduced the effectiveness of the subsequent EDTA extraction because nonvolatile heavy metals were immobilized in soil aggregates after the 550 degrees C treatment. The remediation train of chemical extraction followed by thermal treatment appears to remediate soils that have been contaminated by many nonvolatile heavy metals and Hg. Implications: A remediation train conjoining two or more techniques has been initialized to remove multiple metals. Better understandings of the impacts of treatment sequences, namely, which technique should be employed first on the soil properties and the decontamination efficiency, are in high demand. This study provides a strategy to remove multiple heavy metals including Hg from a contaminated soil. The interactions between thermal treatment and chemical extraction on repartitioning of heavy metals was revealed. The obtained results could offer an integrating strategy to remediate the soil contaminated with both heavy metals and volatile contaminants.

  14. Remedial investigation of the High-Explosives (HE) Process Area, Lawrence Livermore National Laboratory Site 300

    Energy Technology Data Exchange (ETDEWEB)

    Crow, N.B.; Lamarre, A.L.

    1990-08-01

    This report presents the results of a Remedial Investigation (RI) to define the extent of high explosives (HE) compounds and volatile organic compounds (VOCs) found in the soil, rocks, and ground water of the HE Process Area of Lawrence Livermore National Laboratory's (LLNL) Site 300 Facility. The report evaluates potential public health environmental risks associated with these compounds. Hydrogeologic information available before February 15, 1990, is included; however, chemical analyses and water-level data are reported through March 1990. This report is intended to assist the California Regional Water Quality Control Board (RWQCB)--Central Valley Region and the US Environmental Protection Agency (EPA) in evaluating the extent of environmental contamination of the LLNL HE Process Area and ultimately in designing remedial actions. 90 refs., 20 figs., 7 tabs.

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

    Science.gov (United States)

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

    2016-07-01

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

  16. FY 1995 Remedial Investigation Work Plan for Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Watkins, D.R.; Herbes, S.E. [eds.

    1994-12-01

    The purpose of this project is to provide key information needed by decision makers to expedite the process of environmental restoration and to provide the data base required by the Remedial Investigation/Feasibility Study (RI/FS) for Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL). WAG 2 is the major drainage system downgradient of other WAGs that contain significant sources of contamination at ORNL. Field activities to support the remedial investigation for the RI portion include characterization of the nature and extent of contamination in WAG 2 [consisting of White Oak Creek (WOC) and associated tributaries and floodplain, White Oak Lake (WOL), and White Oak Creek Embayment (WOCE)], specifically to support risk-based remediation decisions. The project consists of three phases: Phase 1, initial scoping characterization to determine the need for early action; Phase 2, interim activities during remediation of upslope WAGs to evaluate potential changes in the contamination status of WAG 2 that would necessitate revaluation of the need for early action; and Phase 3, completion of the RI process following remediation of upslope WAGs. Overall RI objectives, consistent with ORNL Environmental Restoration (ER) Program strategic objectives to reduce risks and comply with environmental regulations, are discussed in the WAG 2 Remedial Investigation Plan.

  17. Emerging Technologies and Techniques for Wide Area Radiological Survey and Remediation

    Energy Technology Data Exchange (ETDEWEB)

    Sutton, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zhao, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-03-24

    Technologies to survey and decontaminate wide-area contamination and process the subsequent radioactive waste have been developed and implemented following the Chernobyl nuclear power plant release and the breach of a radiological source resulting in contamination in Goiania, Brazil. These civilian examples of radioactive material releases provided some of the first examples of urban radiological remediation. Many emerging technologies have recently been developed and demonstrated in Japan following the release of radioactive cesium isotopes (Cs-134 and Cs-137) from the Fukushima Dai-ichi nuclear power plant in 2011. Information on technologies reported by several Japanese government agencies, such as the Japan Atomic Energy Agency (JAEA), the Ministry of the Environment (MOE) and the National Institute for Environmental Science (NIES), together with academic institutions and industry are summarized and compared to recently developed, deployed and available technologies in the United States. The technologies and techniques presented in this report may be deployed in response to a wide area contamination event in the United States. In some cases, additional research and testing is needed to adequately validate the technology effectiveness over wide areas. Survey techniques can be deployed on the ground or from the air, allowing a range of coverage rates and sensitivities. Survey technologies also include those useful in measuring decontamination progress and mapping contamination. Decontamination technologies and techniques range from non-destructive (e.g., high pressure washing) and minimally destructive (plowing), to fully destructive (surface removal or demolition). Waste minimization techniques can greatly impact the long-term environmental consequences and cost following remediation efforts. Recommendations on technical improvements to address technology gaps are presented together with observations on remediation in Japan.

  18. The effect of soil type on the electrodialytic remediation of lead-contaminated soil

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Ottosen, Lisbeth M.; Harmon, Thomas C.

    2007-01-01

    experiments with ten representative industrially Pb-contaminated surface soils. Results indicate that Pb-speciation is of primary importance. Specifically, organic matter and stable compounds like PbCrO4 can impede and possibly even preclude soil remediation. In soils rich in carbonate, where the acidic front......This work investigates the influence of soil type on electrodialytic remediation (EDR) of lead (Pb). It is well-known in electrokinetic soil remediation that pH is a key factor, and carbonate influences remediation efficiency negatively. This work provides results from laboratory scale EDR...... is impeded, part of the Pb can be transferred from the soil to the anolyte as negatively charged complexes during the EDR process. The dominant complex is in this case likely to be Pb(CO3)22-. Efficient remediation is however not obtained until all carbonate has dissolved and Pb2+ is transported...

  19. Remediation of Petroleum-contaminated Soil Using Bulrush Straw Powder, Biochar and Nutrients.

    Science.gov (United States)

    Wang, Yanjie; Li, Fayun; Rong, Xiangmin; Song, Haixing; Chen, Jiabo

    2017-05-01

    The aim of this study was to determine the remediation efficiency of petroleum-contaminated soil from an oilfield using different types of remediation treatments under laboratory conditions. Compared with unamended soil as the control treatment (T1), soil samples were amended with bulrush straw powder (T2), with biochar alone (T3) and in combination with nutrients (nitrogen and phosphorus) (T4). The remediation experiment was carried out for 8 weeks. The extent of hydrocarbon degradation was monitored gravimetrically, and the residual oil fractions were analyzed by gas chromatography. The characteristics of the polluted soil (water-holding capacity and nutrients) were improved significantly by biochar addition (p soil can be remediated efficiently by adding biochar and nutrients simultaneously, and this combination of remediation was superior to that observed with added bulrush straw powder.

  20. The use of sustainable 'biochar compost' for remediation of contaminated land

    Science.gov (United States)

    Ryan, Aoife; Street-Perrott, Alayne; Eastwood, Daniel; Brackenbury, Sion

    2014-05-01

    South Wales (UK) has a long industrial history which, since the collapse of the coal-mining industry, has left a large number of contaminated former colliery sites. Bio-remediation of these areas by re-vegetation with native grasses aims to prevent erosion and leaching of pollutants into drainage waters. However, acid pH, low organic-matter content and unsuitable soil structure have limited the success of re-vegetation and prompted research into the development of artificial soils. This study aims to assess the value of creating an artificial soil cover by adding "biochar compost" to the top 10cm of a large volume of contaminated colliery spoil (high in As and Cu) to be moved during construction of a flood-alleviation barrage in Cwm Dulais (Swansea). It is proposed to use biochar, manufactured from chipped biomass sourced from a local stand of invasive Rhododendron ponticum using a BiGchar 1000 fast pyrolysis-gasification unit, in combination with locally produced BSI PAS100-certified Pteridium aquilinum (bracken) compost, to remediate a large area (2.3ha) of landscaped colliery waste and re-establish a cover of native grasses suitable for sheep grazing. Pot and field trials are being used to determine the most appropriate biochar:compost mix. In a 90-day outdoor pot trial, a commercial acid-grassland seed mix was grown in screened (grass samples are being analysed for nutrients, heavy metals and metalloids by elemental analysis (EA) and X-ray fluorescence spectroscopy (XRF). These results will be compared with grass samples collected from Cwm Dulais. Initial findings suggest that addition of biochar compost improved grass growth compared with unamended colliery spoil.

  1. Multi-criteria model to support decision-making for the remediation of urban areas

    Energy Technology Data Exchange (ETDEWEB)

    De Luca, Christiano; Lopes, Ricardo T., E-mail: christiano_luca@hotmail.com, E-mail: ricardo@lin.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Rochedo, Elaine R.R., E-mail: elainerochedo@gmail.com [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Silva, Diogo N.G.; Guimaraes, Jean R.D., E-mail: diogons@gmail.com, E-mail: jeanrdg@biof.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Instituto de Biofisica Carlos Chagas Filho; Rochedo, Pedro R.R., E-mail: rochedopedro@gmail.com [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de de Planejamento Energetico; Wasserman, Maria Angelica V., E-mail: mwasserman@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    Under the environmental modeling Project of radioecology research area of IRD (CNEN), several tools have been developed to support post-emergency activities. Currently, a multi-criteria model is in development with the aim of supporting decision-making processes under the radiological protection point of view. At this stage, we are focusing on the decontamination of urban areas. The model includes five calculation modules: (1) averted doses to the public due to remediation procedures; (2) occupational exposure of remediation workers; (3) properties of the wastes generated by a remediation procedure; (4) classification of each procedure for a specific urban scenario based on previously calculated quantities; and, (5) multi-criteria rank calculation. The classification of procedures is based on two types of criteria previously defined, both also included as input data of the model. The first type, called Subjective Criteria, is based on experts' opinions collected through questionnaires. The second type, called Technical Criteria, is calculated according to the outputs of the three first modules of the program. The output of the model is a rank order list indicating the priority of procedures to use for each different type of urban environment. The use of results based on criteria and methods developed previously to the occurrence of a contamination event intends not only to provide an input to decision-making processes but also to improve public confidence on authorities responsible for the remediation decisions. (author)

  2. Microwave thermal remediation of crude oil contaminated soil enhanced by carbon fiber.

    Science.gov (United States)

    Li, Dawei; Zhang, Yaobin; Quan, Xie; Zhao, Yazhi

    2009-01-01

    Thermal remediation of the soil contaminated with crude oil using microwave heating enhanced by carbon fiber (CF) was explored. The contaminated soil was treated with 2.45 GHz microwave, and CF was added to improve the conversion of microwave energy into thermal energy to heat the soil. During microwave heating, the oil contaminant was removed from the soil matrix and recovered by a condensation system of ice-salt bath. The experimental results indicated that CF could efficiently enhance the microwave heating of soil even with relatively low-dose. With 0.1 wt.% CF, the soil could be heated to approximately 700 degrees C within 4 min using 800 W of microwave irradiation. Correspondingly, the contaminated soil could be highly cleaned up in a short time. Investigation of oil recovery showed that, during the remediation process, oil contaminant in the soil could be efficiently recovered without causing significant secondary pollution.

  3. Remediation of lead contaminated soil by biochar-supported nano-hydroxyapatite.

    Science.gov (United States)

    Yang, Zhangmei; Fang, Zhanqiang; Zheng, Liuchun; Cheng, Wen; Tsang, Pokeung Eric; Fang, Jianzhang; Zhao, Dongye

    2016-10-01

    In this study, a high efficiency and low cost biochar-supported nano-hydroxyapatite (nHAP@BC) material was used in the remediation of lead (Pb)-contaminated soil. The remediation effect of nHAP@BC on Pb-contaminated soil was evaluated through batch experiments. The stability, bioaccessibility of Pb in the soil and the change in soil characteristics are discussed. Furthermore, the effects of the amendments on the growth of cabbage mustard seedlings and the accumulation of Pb were studied. The results showed that the immobilization rates of Pb in the soil were 71.9% and 56.8%, respectively, after a 28 day remediation using 8% nHAP and nHAP@BC materials, and the unit immobilization amount of nHAP@BC was 5.6 times that of nHAP, indicating that nHAP@BC can greatly reduce the cost of remediation of Pb in soil. After the nHAP@BC remediation, the residual fraction Pb increased by 61.4%, which greatly reduced the bioaccessibility of Pb in the soil. Moreover, nHAP@BC could effectively reduce the accumulation of Pb in plants by 31.4%. Overall, nHAP@BC can effectively remediate Pb-contaminated soil and accelerate the recovery of soil fertility.

  4. Use of surfactants for the remediation of contaminated soils: a review.

    Science.gov (United States)

    Mao, Xuhui; Jiang, Rui; Xiao, Wei; Yu, Jiaguo

    2015-03-21

    Due to the great harm caused by soil contamination, there is an increasing interest to apply surfactants to the remediation of a variety of contaminated soils worldwide. This review article summarizes the findings of recent literatures regarding remediation of contaminated soils/sites using surfactants as an enhancing agent. For the surfactant-based remedial technologies, the adsorption behaviors of surfactants onto soil, the solubilizing capability of surfactants, and the toxicity and biocompatibility of surfactants are important considerations. Surfactants can enhance desorption of pollutants from soil, and promote bioremediation of organics by increasing bioavailability of pollutants. The removal of heavy metals and radionuclides from soils involves the mechanisms of dissolution, surfactant-associated complexation, and ionic exchange. In addition to the conventional ionic and nonionic surfactants, gemini surfactants and biosurfactants are also applied to soil remediation due to their benign features like lower critical micelle concentration (CMC) values and better biocompatibility. Mixed surfactant systems and combined use of surfactants with other additives are often adopted to improve the overall performance of soil washing solution for decontamination. Worldwide the field studies and full-scale remediation using surfactant-based technologies are yet limited, however, the already known cases reveal the good prospect of applying surfactant-based technologies to soil remediation.

  5. 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

  6. [Application of organic agents in remediation of heavy metals- contaminated soil].

    Science.gov (United States)

    Sun, Xiaofeng; Wu, Longhua; Luo, Yongming

    2006-06-01

    Organic agents play an important role in the remediation of heavy metals - contaminated soil, and their introduction into practice is a promising strategy to develop an efficient solution for this remediation. This paper summarized the research advances in the application of organic agents to the remediation of heavy metals- polluted soil, including their action mechanisms, advantages and disadvantages, and factors affecting their efficiency. The commonly used organic agents, such as aminopolycarboxylic acid, organic acid, humic acid, biosurfactants, etc., were introduced, and the prospects of organic agents' application were discussed.

  7. A Sustainability Assessment Methodology for Prioritizing the Technologies of Groundwater Contamination Remediation

    DEFF Research Database (Denmark)

    An, Da; Xi, Beidou; Wang, Yue

    2016-01-01

    More and more groundwater has 23 been polluted recently, and technologies for groundwater contamination remediation are of vital importance; however, it is usually difficult for the users to select the most suitable technology among multiple alternatives. In order to address this, this study aims...... at developing a sustainability assessment framework for prioritizing the technologies for groundwater contamination remediation by combining the concept of sustainability and multi-criteria decision making (MCDM) method. A criterion system which consists of six criteria in three aspects has been proposed...... for sustainability assessment of technologies for groundwater contamination remediation, and a novel MCDM method by combining the logarithmic fuzzy preference programming based fuzzy analytic hierarchy process and the improved ELECTRE method has been developed for prioritizing the alternatives. In order...

  8. A comprehensive guide of remediation technologies for oil contaminated soil - Present works and future directions.

    Science.gov (United States)

    Lim, Mee Wei; Lau, Ee Von; Poh, Phaik Eong

    2016-08-15

    Oil spills result in negative impacts on the environment, economy and society. Due to tidal and waves actions, the oil spillage affects the shorelines by adhering to the soil, making it difficult for immediate cleaning of the soil. As shoreline clean-up is the most costly component of a response operation, there is a need for effective oil remediation technologies. This paper provides a review on the remediation technologies for soil contaminated with various types of oil, including diesel, crude oil, petroleum, lubricating oil, bitumen and bunker oil. The methods discussed include solvent extraction, bioremediation, phytoremediation, chemical oxidation, electrokinetic remediation, thermal technologies, ultrasonication, flotation and integrated remediation technologies. Each of these technologies was discussed, and associated with their advantages, disadvantages, advancements and future work in detail. Nonetheless, it is important to note that no single remediation technology is considered the best solution for the remediation of oil contaminated soil. This review provides a comprehensive literature on the various remediation technologies studied in the removal of different oil types from soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Sustainability likelihood of remediation options for metal-contaminated soil/sediment.

    Science.gov (United States)

    Chen, Season S; Taylor, Jessica S; Baek, Kitae; Khan, Eakalak; Tsang, Daniel C W; Ok, Yong Sik

    2017-05-01

    Multi-criteria analysis and detailed impact analysis were carried out to assess the sustainability of four remedial alternatives for metal-contaminated soil/sediment at former timber treatment sites and harbour sediment with different scales. The sustainability was evaluated in the aspects of human health and safety, environment, stakeholder concern, and land use, under four different scenarios with varying weighting factors. The Monte Carlo simulation was performed to reveal the likelihood of accomplishing sustainable remediation with different treatment options at different sites. The results showed that in-situ remedial technologies were more sustainable than ex-situ ones, where in-situ containment demonstrated both the most sustainable result and the highest probability to achieve sustainability amongst the four remedial alternatives in this study, reflecting the lesser extent of off-site and on-site impacts. Concerns associated with ex-situ options were adverse impacts tied to all four aspects and caused by excavation, extraction, and off-site disposal. The results of this study suggested the importance of considering the uncertainties resulting from the remedial options (i.e., stochastic analysis) in addition to the overall sustainability scores (i.e., deterministic analysis). The developed framework and model simulation could serve as an assessment for the sustainability likelihood of remedial options to ensure sustainable remediation of contaminated sites. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Petroleum contaminated ground-water: Remediation using activated carbon.

    OpenAIRE

    2006-01-01

    Ground-water contamination resulting from the leakage of crude oil and refined petroleum products during extraction and processing operations is a serious and a growing environmental problem in Nigeria. Consequently, a study of the use of activated carbon (AC) in the clean up was undertaken with the aim of reducing the water contamination to a more acceptable level. In the experiments described, crude-oil contamination of ground water was simulated under laboratory conditions using ground-wat...

  11. Mining-related sediment and soil contamination in a large Superfund site: Characterization, habitat implications, and remediation

    Science.gov (United States)

    Juracek, Kyle E.; Drake, K. D.

    2016-01-01

    Historical mining activity (1850–1970) in the now inactive Tri-State Mining District provided an ongoing source of lead and zinc to the environment including the US Environmental Protection Agency Superfund site located in Cherokee County, southeast Kansas, USA. The resultant contamination adversely affected biota and caused human health problems and risks. Remediation in the Superfund site requires an understanding of the magnitude and extent of contamination. To provide some of the required information, a series of sediment and soil investigations were conducted in and near the Superfund site to characterize lead and zinc contamination in the aquatic and floodplain environments along the main-stem Spring River and its major tributaries. In the Superfund site, the most pronounced lead and zinc contamination, with concentrations that far exceed sediment quality guidelines associated with potential adverse biological effects, was measured for streambed sediments and floodplain soils located within or downstream from the most intensive mining-affected areas. Tributary streambeds and floodplains in affected areas are heavily contaminated with some sites having lead and zinc concentrations that are an order of magnitude (or more) greater than the sediment quality guidelines. For the main-stem Spring River, the streambed is contaminated but the floodplain is mostly uncontaminated. Measured lead and zinc concentrations in streambed sediments, lakebed sediments, and floodplain soils documented a persistence of the post-mining contamination on a decadal timescale. These results provide a basis for the prioritization, development, and implementation of plans to remediate contamination in the affected aquatic and floodplain environments within the Superfund site.

  12. Mining-Related Sediment and Soil Contamination in a Large Superfund Site: Characterization, Habitat Implications, and Remediation.

    Science.gov (United States)

    Juracek, K E; Drake, K D

    2016-10-01

    Historical mining activity (1850-1970) in the now inactive Tri-State Mining District provided an ongoing source of lead and zinc to the environment including the US Environmental Protection Agency Superfund site located in Cherokee County, southeast Kansas, USA. The resultant contamination adversely affected biota and caused human health problems and risks. Remediation in the Superfund site requires an understanding of the magnitude and extent of contamination. To provide some of the required information, a series of sediment and soil investigations were conducted in and near the Superfund site to characterize lead and zinc contamination in the aquatic and floodplain environments along the main-stem Spring River and its major tributaries. In the Superfund site, the most pronounced lead and zinc contamination, with concentrations that far exceed sediment quality guidelines associated with potential adverse biological effects, was measured for streambed sediments and floodplain soils located within or downstream from the most intensive mining-affected areas. Tributary streambeds and floodplains in affected areas are heavily contaminated with some sites having lead and zinc concentrations that are an order of magnitude (or more) greater than the sediment quality guidelines. For the main-stem Spring River, the streambed is contaminated but the floodplain is mostly uncontaminated. Measured lead and zinc concentrations in streambed sediments, lakebed sediments, and floodplain soils documented a persistence of the post-mining contamination on a decadal timescale. These results provide a basis for the prioritization, development, and implementation of plans to remediate contamination in the affected aquatic and floodplain environments within the Superfund site.

  13. Mining-Related Sediment and Soil Contamination in a Large Superfund Site: Characterization, Habitat Implications, and Remediation

    Science.gov (United States)

    Juracek, K. E.; Drake, K. D.

    2016-10-01

    Historical mining activity (1850-1970) in the now inactive Tri-State Mining District provided an ongoing source of lead and zinc to the environment including the US Environmental Protection Agency Superfund site located in Cherokee County, southeast Kansas, USA. The resultant contamination adversely affected biota and caused human health problems and risks. Remediation in the Superfund site requires an understanding of the magnitude and extent of contamination. To provide some of the required information, a series of sediment and soil investigations were conducted in and near the Superfund site to characterize lead and zinc contamination in the aquatic and floodplain environments along the main-stem Spring River and its major tributaries. In the Superfund site, the most pronounced lead and zinc contamination, with concentrations that far exceed sediment quality guidelines associated with potential adverse biological effects, was measured for streambed sediments and floodplain soils located within or downstream from the most intensive mining-affected areas. Tributary streambeds and floodplains in affected areas are heavily contaminated with some sites having lead and zinc concentrations that are an order of magnitude (or more) greater than the sediment quality guidelines. For the main-stem Spring River, the streambed is contaminated but the floodplain is mostly uncontaminated. Measured lead and zinc concentrations in streambed sediments, lakebed sediments, and floodplain soils documented a persistence of the post-mining contamination on a decadal timescale. These results provide a basis for the prioritization, development, and implementation of plans to remediate contamination in the affected aquatic and floodplain environments within the Superfund site.

  14. Feasilbility of phytoextraction to remediate cadmium and zinc contaminated soils

    NARCIS (Netherlands)

    Koopmans, G.F.; Romkens, P.F.A.M.; Fokkema, M.J.; Song, J.; Luo, Y.M.; Japenga, J.; Zhao, F.J.

    2008-01-01

    A Cd and Zn contaminated soil was mixed and equilibrated with an uncontaminated, but otherwise similar soil to establish a gradient in soil contamination levels. Growth of Thlaspi caerulescens (Ganges ecotype) significantly decreased the metal concentrations in soil solution. Plant uptake of Cd and

  15. IN SITU REMEDIATION OF CONTAMINATED SEDIMENTS - ACTIVE CAPPING TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Knox, A.; Roberts, J.; Paller, M.; Reible, D.

    2010-09-02

    Active capping is a relatively new approach for treating contaminated sediments. It involves applying chemically reactive amendments to the sediment surface. The main role of active caps is to stabilize contaminants in contaminated sediments, lower the bioavailable pool of contaminants, and reduce the release of contaminants to the water column. Metals are common contaminants in many marine and fresh water environments as a result of industrial and military activities. The mobile, soluble forms of metals are generally considered toxic. Induced chemical precipitation of these metals can shift toxic metals from the aqueous phase to a solid, precipitated phase which is often less bioavailable. This approach can be achieved through application of sequestering agents such as rock phosphates, organoclays, zeolites, clay minerals, and biopolymers (e.g., chitosan) in active capping technology. Active capping holds great potential for a more permanent solution that avoids residual risks resulting from contaminant migration through the cap or breaching of the cap. In addition to identifying superior active capping agents, research is needed to optimize application techniques, application rates, and amendment combinations that maximize sequestration of contaminants. A selected set of active capping treatment technologies has been demonstrated at a few sites, including a field demonstration at the Savannah River Site, Aiken, SC. This demonstration has provided useful information on the effects of sequestering agents on metal immobilization, bioavailability, toxicity, and resistance to mechanical disturbance.

  16. Arsenic contamination, consequences and remediation techniques: a review.

    Science.gov (United States)

    Singh, Rachana; Singh, Samiksha; Parihar, Parul; Singh, Vijay Pratap; Prasad, Sheo Mohan

    2015-02-01

    The exposure to low or high concentrations of arsenic (As), either due to the direct consumption of As contaminated drinking water, or indirectly through daily intake of As contaminated food may be fatal to the human health. Arsenic contamination in drinking water threatens more than 150 millions peoples all over the world. Around 110 millions of those peoples live in 10 countries in South and South-East Asia: Bangladesh, Cambodia, China, India, Laos, Myanmar, Nepal, Pakistan, Taiwan and Vietnam. Therefore, treatment of As contaminated water and soil could be the only effective option to minimize the health hazard. Therefore, keeping in view the above facts, an attempt has been made in this paper to review As contamination, its effect on human health and various conventional and advance technologies which are being used for the removal of As from soil and water. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Remediation of uranium in-situ leaching area at Straz Pod Ralskem, Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Vokal, Vojtech; Muzak, Jiri; Ekert, Vladimir [DIAMO, s. e., TUU, Pod Vinici 84, Straz pod Ralskem, 471 27 (Czech Republic)

    2013-07-01

    A large-scale development in exploration and production of uranium ores in the Czech Republic was done in the 2nd half of the 20. century. Many uranium deposits were discovered in the territory of the Czech Republic. One of the most considerable deposits in the Czech Republic is the site Hamr na Jezere - Straz pod Ralskem where both mining methods - the underground mining and the acidic in-situ leaching - were used. The extensive production of uranium led to widespread environmental impacts and contamination of ground waters. Over the period of 'chemical' leaching of uranium (ca. 32 years), a total of more than 4 million tons of sulphuric acid and other chemicals have been injected into the ground. Most of the products (approx. 99.5 %) of the acids reactions with the rocks are located in the Cenomanian aquifer. The contamination of Cenomanian aquifer covers the area larger then 27 km{sup 2}. The influenced volume of groundwater is more than 380 million m{sup 3}. The total amount of dissolved SO{sub 4}{sup 2-} is about 3.6 million tons. After 1990 a large-scale environmental program was established and the Czech government decided to liquidate the ISL Mine and start the remediation in 1996. The remediation consists of contaminated groundwater pumping, removing of the contaminants and discharging or reinjection of treated water. Nowadays four main remedial technological installations with sufficient capacity for reaching of the target values of remedial parameters in 2037 are used - the 'Station for Acid Solutions Liquidation No. One', the 'Mother liquor reprocessing' station, the 'Neutralization and Decontamination Station NDS 6' and the 'Neutralization and Decontamination Station NDS 10'. It is expected that the amount of withdrawn contaminants will vary from 80 000 to 120 000 tons per year. Total costs of all remediation activities are expected to be in excess of 2 billion EUR. (authors)

  18. Use of surfactants for the remediation of contaminated soils: A review

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Xuhui, E-mail: clab@whu.edu.cn [School of Resource and Environmental Science, Wuhan University, Wuhan 430072 (China); Jiang, Rui; Xiao, Wei [School of Resource and Environmental Science, Wuhan University, Wuhan 430072 (China); Yu, Jiaguo, E-mail: jiaguoyu@yahoo.com [State Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China)

    2015-03-21

    Highlights: • The recent advances in use of surfactant for soil remediation are reviewed. • The mechanisms of surfactant-based soil remediation are discussed. • A review on the application of different types of surfactants is made. • The future research direction of surfactant-based technologies is suggested. - Abstract: Due to the great harm caused by soil contamination, there is an increasing interest to apply surfactants to the remediation of a variety of contaminated soils worldwide. This review article summarizes the findings of recent literatures regarding remediation of contaminated soils/sites using surfactants as an enhancing agent. For the surfactant-based remedial technologies, the adsorption behaviors of surfactants onto soil, the solubilizing capability of surfactants, and the toxicity and biocompatibility of surfactants are important considerations. Surfactants can enhance desorption of pollutants from soil, and promote bioremediation of organics by increasing bioavailability of pollutants. The removal of heavy metals and radionuclides from soils involves the mechanisms of dissolution, surfactant-associated complexation, and ionic exchange. In addition to the conventional ionic and nonionic surfactants, gemini surfactants and biosurfactants are also applied to soil remediation due to their benign features like lower critical micelle concentration (CMC) values and better biocompatibility. Mixed surfactant systems and combined use of surfactants with other additives are often adopted to improve the overall performance of soil washing solution for decontamination. Worldwide the field studies and full-scale remediation using surfactant-based technologies are yet limited, however, the already known cases reveal the good prospect of applying surfactant-based technologies to soil remediation.

  19. INNOVATIVE IN-SITU REMEDIATION OF CONTAMINATED SEDIMENTS FOR SIMULTANEOUS CONTROL OF CONTAMINATION AND EROSION

    Energy Technology Data Exchange (ETDEWEB)

    Knox, A; Michael Paller, M; Danny D. Reible, D; Ioana G. Petrisor, I

    2007-11-28

    of biopolymer coated sand to erosion. Although the ability of active cap materials to remediate contaminants has been emphasized in this study, it is also important to ensure that these materials do not have deleterious effects on the environment. Therefore, promising amendments were evaluated for toxicity using 10 day sediment toxicity tests, the standardized Toxicity Characteristic Leaching Procedure (TCLP), and measurement of metal concentrations in aqueous extracts from the amendments. Metal concentrations were below TCLP limits, EPA ambient water quality criteria, and other ecological screening values These results showed that apatite, organoclay, and biopolymer coated sand do not release metals. The sediment toxicity tests indicated that apatite and biopolymer coated sand are unlikely to adversely affect benthic organisms, even when used in high concentrations.

  20. A Cercla-Based Decision Model to Support Remedy Selection for an Uncertain Volume of Contaminants at a DOE Facility

    Energy Technology Data Exchange (ETDEWEB)

    Christine E. Kerschus

    1999-03-31

    The Paducah Gaseous Diffusion Plant (PGDP) operated by the Department of Energy is challenged with selecting the appropriate remediation technology to cleanup contaminants at Waste Area Group (WAG) 6. This research utilizes value-focused thinking and multiattribute preference theory concepts to produce a decision analysis model designed to aid the decision makers in their selection process. The model is based on CERCLA's five primary balancing criteria, tailored specifically to WAG 6 and the contaminants of concern, utilizes expert opinion and the best available engineering, cost, and performance data, and accounts for uncertainty in contaminant volume. The model ranks 23 remediation technologies (trains) in their ability to achieve the CERCLA criteria at various contaminant volumes. A sensitivity analysis is performed to examine the effects of changes in expert opinion and uncertainty in volume. Further analysis reveals how volume uncertainty is expected to affect technology cost, time and ability to meet the CERCLA criteria. The model provides the decision makers with a CERCLA-based decision analysis methodology that is objective, traceable, and robust to support the WAG 6 Feasibility Study. In addition, the model can be adjusted to address other DOE contaminated sites.

  1. Physical countermeasures to sustain acceptable living and working conditions in radioactively contaminated residential areas

    DEFF Research Database (Denmark)

    Andersson, Kasper Grann; Roed, Jørn; Eged, K.;

    2003-01-01

    The Chernobyl accident highlighted the need in nuclear preparedness for robust, effective and sustainable countermeasure strategies for restoration of radioactively contaminated residential areas. Under the EC-supported STRATEGY project a series ofinvestigations were made of countermeasures...... of wastes generated by countermeasures had to be described separately to provide room for the required level of detail. The information is mainly intended as atool for decision makers and planners and constitutes a basis for the STRATEGY decision framework for remediation of contaminated urban areas....

  2. Defining remediation targets and treatment options for hydrocarbon contamination in Quttinirpaaq National Park (Ellesmere Island) : a holistic approach

    Energy Technology Data Exchange (ETDEWEB)

    Sanscartier, D.; Laing, T.; Zeeb, B.; Li, J.; Mohn, W.; Mouland, G.; Glenfield, R.; Reimer, K.; Prevost, J.C. [Royal Military Coll. of Canada, Kingston, ON (Canada)

    2007-07-01

    A combined field investigation and research program to determine remediation targets for the Quttinirpaaq National Park was described. The park is a polar desert located on the northeastern tip of Ellesmere Island. The aim of the program was to define an appropriate remediation strategy for the area, which contains petroleum hydrocarbon contamination at various locations. Generic evaluation criteria that are successfully used in other regions of Canada are not appropriate for investigating Arctic ecosystems. A risk assessment approach was used to evaluate hydrocarbon concentrations that may pose a risk to plants and invertebrates living within the soil. Soil invertebrates were collected from hydrocarbon-contaminated and non-contaminated soils to assess if there was a difference between invertebrate communities at the sites. Data from the study were then used to evaluate risk as well as to derive F3 eco-soil contact remediation criteria. Microcosms containing small amounts of soil were used to investigate mineralization rates under different amendment regimes over a period of 6 weeks. Bench-scale bioreactors were then used to mimic conditions in the field. Bioremediation treatment plots were then established at 2 sites in the park. Hydrocarbon absorbent polymer technology (HAPT) was also used to extract hydrocarbons from soils. Both the laboratory and the field research programs showed that bioremediation is a good treatment option for the heavier hydrocarbons found at the park. 10 refs., 3 figs.

  3. Biosurfactant technology for remediation of cadmium and lead contaminated soils.

    Science.gov (United States)

    Juwarkar, Asha A; Nair, Anupa; Dubey, Kirti V; Singh, S K; Devotta, Sukumar

    2007-08-01

    This research focuses on column experiments conducted to evaluate the potential of environmentally compatible rhamnolipid biosurfactant produced by Pseudomonas aeruginosa strain BS2 to remove heavy metals (Cd and Pb) from artificially contaminated soil. Results have shown that di-rhamnolipid removes not only the leachable or available fraction of Cd and Pb but also the bound metals as compared to tap water which removed the mobile fraction only. Washing of contaminated soil with tap water revealed that approximately 2.7% of Cd and 9.8% of Pb in contaminated soil was in freely available or weakly bound forms whereas washing with rhamnolipid removed 92% of Cd and 88% of Pb after 36 h of leaching. This indicated that di-rhamnolipid selectively favours mobilization of metals in the order of Cd>Pb. Biosurfactant specificity observed towards specific metal will help in preferential elution of specific contaminant using di-rhamnolipid. It was further observed that pH of the leachates collected from heavy metal contaminated soil column treated with di-rhamnolipid solution was low (6.60-6.78) as compared to that of leachates from heavy metal contaminated soil column treated with tap water (pH 6.90-7.25), which showed high dissolution of metal species from the contaminated soil and effective leaching of metals with treatment with biosurfactant. The microbial population of the contaminated soil was increased after removal of metals by biosurfactant indicating the decrease of toxicity of metals to soil microflora. This study shows that biosurfactant technology can be an effective and nondestructive method for bioremediation of cadmium and lead contaminated soil.

  4. Remediation of the Highland Drive South Ravine, Port Hope, Ontario: Contaminated Groundwater Discharge Management Using Permeable Reactive Barriers and Contaminated Sediment Removal - 13447

    Energy Technology Data Exchange (ETDEWEB)

    Smyth, David; Roos, Gillian [Golder Associates Ltd., 2390 Argentia Road, Mississauga, ON L5N 5Z7 (Canada); Ferguson Jones, Andrea [MMM Group Ltd., 100 Commerce Valley Drive West, Thornhill, ON L3T 0A1 (Canada); Case, Glenn [AECL Port Hope Area Initiative Management Office, 115 Toronto Road, Port Hope, ON L1A 3S4 (Canada); Yule, Adam [Public Works and Government Services Canada, 4900 Yonge Street, 11th Floor, Toronto, ON, M2N 6A6 (Canada)

    2013-07-01

    The Highland Drive South Ravine (HDSR) is the discharge area for groundwater originating from the Highland Drive Landfill, the Pine Street North Extension (PSNE) roadbed parts of the Highland Drive roadbed and the PSNE Consolidation Site that contain historical low-level radioactive waste (LLRW). The contaminant plume from these LLRW sites contains elevated concentrations of uranium and arsenic and discharges with groundwater to shallow soils in a wet discharge area within the ravine, and directly to Hunt's Pond and Highland Drive South Creek, which are immediately to the south of the wet discharge area. Remediation and environmental management plans for HDSR have been developed within the framework of the Port Hope Project and the Port Hope Area Initiative. The LLRW sites will be fully remediated by excavation and relocation to a new Long-Term Waste Management Facility (LTWMF) as part of the Port Hope Project. It is projected, however, that the groundwater contaminant plume between the remediated LLRW sites and HDSR will persist for several hundreds of years. At the HDSR, sediment remediation within Hunt's Ponds and Highland Drive South Creek, excavation of the existing and placement of clean fill will be undertaken to remove current accumulations of solid-phase uranium and arsenic associated with the upper 0.75 m of soil in the wet discharge area, and permeable reactive barriers (PRBs) will be used for in situ treatment of contaminated groundwater to prevent the ongoing discharge of uranium and arsenic to the area in HDSR where shallow soil excavation and replacement has been undertaken. Bench-scale testing using groundwater from HDSR has confirmed excellent treatment characteristics for both uranium and arsenic using permeable reactive mixtures containing granular zero-valent iron (ZVI). A sequence of three PRBs containing ZVI and sand in backfilled trenches has been designed to intercept the groundwater flow system prior to its discharge to the ground

  5. Evaluation of Final Radiological Conditions at Areas of the Niagara Falls Storage Site Remediated under the Formerly Utilized Sites Remedial Action Program - 12184

    Energy Technology Data Exchange (ETDEWEB)

    Clayton, Christopher [U.S Department of Energy Office of Legacy Management, Washington, DC (United States); Kothari, Vijendra [U.S Department of Energy Office of Legacy Management, Morgantown, West Virginia (United States); Starr, Ken [U.S Department of Energy Office of Legacy Management, Westminster, Colorado (United States); Widdop, Michael; Gillespie, Joey [SM Stoller Corporation, Grand Junction, Colorado (United States)

    2012-07-01

    the U.S. Army Corps of Engineers and state and federal regulators. After review of historical site documentation, DOE reports, and USACE radiological data, DOE concluded the following: - DOE had access to adequate documentation to evaluate site conditions at the former LOOW. This is important to confirm now, while institutional knowledge of early FUSRAP work remains available. - DOE remediated the completed VPs to conditions that are protective for unrestricted residential use. Sample and walkover gamma scan results indicate that no wastes remain that exceed cleanup criteria. - Process knowledge and field observations establish that Cs-137 is the predominant radionuclide in the KAPL waste stream. Cs-137, a strong gamma emitter, was used as an indicator for remediation of KAPL waste. Other radionuclides were present in much lower relative concentrations and were likely also removed during remediation of the VPs. - KAPL contaminants were removed during remedial activities at the former LOOW as either co-located or co-mingled with other radionuclides. - For the active VPs (VP-E, VP-E', and VP-G), results of DOE's cleanup of the accessible portions of these properties indicate that KAPL waste does not remain at concentrations greater than the DOE cleanup limit: - Inaccessible areas were not associated with historic KAPL waste handling. Therefore, it is unlikely that KAPL waste remains on the active VPs. - Because gamma activity was used by DOE during remediation/verification activities for excavation control, additional USACE cleanup of FUSRAP wastes on these properties will likely result in the remediation of any co-located residual KAPL wastes to acceptable levels or identification of KAPL waste that is not co-located. - Although USACE has not established a cleanup level for Cs-137 on the active NFSS VPs, DOE assessment and remediation data indicate that assessed Cs-137 was remediated and significant Cs-137 is unlikely to remain. Because of the low likelihood

  6. Reducing the bioavailability of cadmium in contaminated soil by dithiocarbamate chitosan as a new remediation.

    Science.gov (United States)

    Yin, Zheng; Cao, Jingjing; Li, Zhen; Qiu, Dong

    2015-07-01

    Dithiocarbamate chitosan (DTC-CTS) was used as a new amendment for remediation of cadmium (Cd)-contaminated soils to reduce the Cd bioavailability. Arabidopsis thaliana was chosen as a model plant to evaluate its efficiency. It was found that DTC-CTS could effectively improve the growth of A. thaliana. The amount of Cd up-taken by A. thaliana could be decreased by as much as 50% compared with that grown in untreated Cd-contaminated soil samples. The chlorophyll content and the aerial biomass of Arabidopsis also increased substantially and eventually returned to a level comparable to plants grown in non-contaminated soils, with the addition of DTC-CTS. These findings suggested that DTC-CTS amendment could be effective in immobilizing Cd and mitigating its accumulation in plants grown in Cd-contaminated soils, with potential application as an in situ remediation of Cd-polluted soils.

  7. Electrokinetic remediation of fluorine-contaminated soil and its impact on soil fertility.

    Science.gov (United States)

    Zhou, Ming; Wang, Hui; Zhu, Shufa; Liu, Yana; Xu, Jingming

    2015-11-01

    Compared to soil pollution by heavy metals and organic pollutants, soil pollution by fluorides is usually ignored in China. Actually, fluorine-contaminated soil has an unfavorable influence on human, animals, plants, and surrounding environment. This study reports on electrokinetic remediation of fluorine-contaminated soil and the effects of this remediation technology on soil fertility. Experimental results showed that electrokinetic remediation using NaOH as the anolyte was a considerable choice to eliminate fluorine in contaminated soils. Under the experimental conditions, the removal efficiency of fluorine by the electrokinetic remediation method was 70.35%. However, the electrokinetic remediation had a significant impact on the distribution and concentrations of soil native compounds. After the electrokinetic experiment, in the treated soil, the average value of available nitrogen was raised from 69.53 to 74.23 mg/kg, the average value of available phosphorus and potassium were reduced from 20.05 to 10.39 mg/kg and from 61.31 to 51.58 mg/kg, respectively. Meanwhile, the contents of soil available nitrogen and phosphorus in the anode regions were higher than those in the cathode regions, but the distribution of soil available potassium was just the opposite. In soil organic matter, there was no significant change. These experiment results suggested that some steps should be taken to offset the impacts, after electrokinetic treatment.

  8. Physicochemical and biological quality of soil in hexavalent chromium-contaminated soils as affected by chemical and microbial remediation.

    Science.gov (United States)

    Liao, Yingping; Min, Xiaobo; Yang, Zhihui; Chai, Liyuan; Zhang, Shujuan; Wang, Yangyang

    2014-01-01

    Chemical and microbial methods are the main remediation technologies for chromium-contaminated soil. These technologies have progressed rapidly in recent years; however, there is still a lack of methods for evaluating the chemical and biological quality of soil after different remediation technologies have been applied. In this paper, microbial remediation with indigenous bacteria and chemical remediation with ferrous sulphate were used for the remediation of soils contaminated with Cr(VI) at two levels (80 and 1,276 mg kg(-1)) through a column leaching experiment. After microbial remediation with indigenous bacteria, the average concentration of water-soluble Cr(VI) in the soils was reduced to less than 5.0 mg kg(-1). Soil quality was evaluated based on 11 soil properties and the fuzzy comprehensive assessment method, including fuzzy mathematics and correlative analysis. The chemical fertility quality index was improved by one grade using microbial remediation with indigenous bacteria, and the biological fertility quality index increased by at least a factor of 6. Chemical remediation with ferrous sulphate, however, resulted in lower levels of available phosphorus, dehydrogenase, catalase and polyphenol oxidase. The result showed that microbial remediation with indigenous bacteria was more effective for remedying Cr(VI)-contaminated soils with high pH value than chemical remediation with ferrous sulphate. In addition, the fuzzy comprehensive evaluation method was proven to be a useful tool for monitoring the quality change in chromium-contaminated soils.

  9. BIOREGIS software platform based on GIS technology to support in-situ remediation of petroleum contaminated sites. Case study: razvad - dambovita county, Romania

    Energy Technology Data Exchange (ETDEWEB)

    Anicai, Ovidiu [Institute for Computers - ITC SA, Bucharest (Romania); Anicai, Liana [PSV COMPANY SA, Direction of Research, Bucharest (Romania)

    2011-12-15

    With a need for the management of petroleum contaminated sites on Romanian territory, an experimental software platform involving ESRI-ArcGIS technologies (BIOREGIS) is presented in this study. The BIOREGIS platform is aimed to: (i) Build the structure of relational, standardized databases to store spatial and textual characteristic information on polluted sites for further risk analysis and planning of remediation actions, (ii) improve the pollution risk assessment methodology for Romanian petroleum contaminated sites and its informatics implementation, and (iii) develop and operate the software platform for pollution risk based management involving GIS/remote sensing technologies and remediation activities. The operation of BIOREGIS has been tested for a pilot contaminated area situated at Razvad - Dambovita County, which has been subjected to in situ remediation procedures involving both bioremediation and electrokinetic processes. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. [Microwave thermal remediation of soil contaminated with crude oil enhanced by granular activated carbon].

    Science.gov (United States)

    Li, Da-Wei; Zhang, Yao-Bin; Quan, Xie; Zhao, Ya-Zhi

    2009-02-15

    The advantage of rapid, selective and simultaneous heating of microwave heating technology was taken to remediate the crude oil-contaminated soil rapidly and to recover the oil contaminant efficiently. The contaminated soil was processed in the microwave field with addition of granular activated carbon (GAC), which was used as strong microwave absorber to enhance microwave heating of the soil mixture to remove the oil contaminant and recover it by a condensation system. The influences of some process parameters on the removal of the oil contaminant and the oil recovery in the remediation process were investigated. The results revealed that, under the condition of 10.0% GAC, 800 W microwave power, 0.08 MPa absolute pressure and 150 mL x min(-1) carrier gas (N2) flow-rate, more than 99% oil removal could be obtained within 15 min using this microwave thermal remediation enhanced by GAC; at the same time, about 91% of the oil contaminant could be recovered without significant changes in chemical composition. In addition, the experiment results showed that GAC can be reused in enhancing microwave heating of soil without changing its enhancement efficiency obviously.

  11. Experimental investigation of enhanced remediation of contaminated soil using ultrasound effect

    Directory of Open Access Journals (Sweden)

    Adegbola Adeyinka

    2014-06-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE In the development of an effective ground remediation method, there has been significant research focusing on the technique of enhancing soil-flushing method The soil flushing method enhanced by ultrasonic waves is a new technique that is potentially an effective method for in situ remediation of the ground contaminated by NAPL hydrocarbons. The research work investigated the effectiveness of sonication in the soil flushing method for a range of conditions involving treatment time, hydraulic gradient and the discharge velocity. The experimental investigation of the study was conducted using the inbuilt ultrasonic generator (NEE 555 timer stable multi-vibrator and soil flushing apparatus to remove the contaminant from the soils. The test result indicated that the rate of the contaminant extraction increased considerably with increasing sonication time up to 120seconds with 34% contaminant removed without sonication and 64.05% contaminant removed with sonication and started decreasing at the level where cavitation occurred. Increasing the sonication time also increase the contaminant removal up to the level where cavitation occurs. The effectiveness of sonication decreases with hydraulic gradient but eventually becomes constant under higher flow rates and also is highly related with the discharge velocity. Results obtained showed that sonication can enhance pollutant removal. Keywords: Soil-Flushing Method, NAPL Hydrocarbons, Sonication, Soil Remediation, Cavitation.

  12. Geophysical Monitoring of Hydrocarbon-Contaminated Soils Remediated with a Bioelectrochemical System.

    Science.gov (United States)

    Mao, Deqiang; Lu, Lu; Revil, André; Zuo, Yi; Hinton, John; Ren, Zhiyong Jason

    2016-08-01

    Efficient noninvasive techniques are desired for monitoring the remediation process of contaminated soils. We applied the direct current resistivity technique to image conductivity changes in sandbox experiments where two sandy and clayey soils were initially contaminated with diesel hydrocarbon. The experiments were conducted over a 230 day period. The removal of hydrocarbon was enhanced by a bioelectrochemical system (BES) and the electrical potentials of the BES reactors were also monitored during the course of the experiment. We found that the variation in electrical conductivity shown in the tomograms correlate well with diesel removal from the sandy soil, but this is not the case with the clayey soil. The clayey soil is characterized by a larger specific surface area and therefore a larger surface conductivity. In sandy soil, the removal of the diesel and products from degradation leads to an increase in electrical conductivity during the first 69 days. This is expected since diesel is electrically insulating. For both soils, the activity of BES reactors is moderately imaged by the inverted conductivity tomogram of the reactor. An increase in current production by electrochemically active bacteria activity corresponds to an increase in conductivity of the reactor.

  13. ECONOMICS ANALYSIS OF THE IMPLEMENTATION OF PERMEABLE REACTIVE BARRIERS FOR REMEDIATION OF CONTAMINATED GROUND WATER

    Science.gov (United States)

    This report presents an analysis of the cost of using permeable reactive barriers to remediate contaminated ground water. When possible, these costs are compared with the cost of pump-and-treat technology for similar situations. Permeable reactive barriers are no longer perceiv...

  14. Grand challenge problems in environmental modeling and remediation: groundwater contaminant transport

    Energy Technology Data Exchange (ETDEWEB)

    Todd Arbogast; Steve Bryant; Clint N. Dawson; Mary F. Wheeler

    1998-08-31

    This report describes briefly the work of the Center for Subsurface Modeling (CSM) of the University of Texas at Austin (and Rice University prior to September 1995) on the Partnership in Computational Sciences Consortium (PICS) project entitled Grand Challenge Problems in Environmental Modeling and Remediation: Groundwater Contaminant Transport.

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

    NARCIS (Netherlands)

    Dijke, van M.I.J.

    1997-01-01

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

  16. Quantification of the effect of spatially varying environmental contaminants into a cost model for soil remediation

    NARCIS (Netherlands)

    Broos, J.M.; Aarts, L.; Tooren, C.F.; Stein, A.

    1999-01-01

    In this study we investigated the effects of spatial variability of soil contaminants on cost calculations for soil remediation. Most cost models only provide a single figure, whereas spatial variability is one of the sources to contribute to the uncertainty. A cost model is applied to a study site

  17. A novel integrated active capping technique for the remediation of nitrobenzene-contaminated sediment.

    Science.gov (United States)

    Sun, Hongwen; Xu, Xiaoyang; Gao, Guandao; Zhang, Zizhong; Yin, Peijie

    2010-10-15

    The objective of this study was to develop a novel integrated active capping system and to investigate its efficiency in the remediation of nitrobenzene-contaminated sediment. An integrated Fe(0)-sorbent-microorganism remediation system was proposed as an in situ active capping technique to remediate nitrobenzene-contaminated sediment. In this system, nitrobenzene was reduced to aniline by Fe(0), which has a much better biodegradability. The sorption capacity and structural properties of cinder was measured to examine its applicability as the sorbent and matrix for this integrated capping system. Indigenous microorganisms from Songhuajiang River sediment, which was contaminated by nitrobenzene and aniline in Chinese Petrochemical Explosion in Jilin, were acquired one month after the explosion and used in this active capping system to degrade nitrobenzene and its reduced product, aniline. A bench-scale remediation experiment was conducted on a mimicked nitrobenzene-contaminated sediment to investigate the efficiency of the integrated capping system and the synergistic effects of the combined components in the active capping system. The results show that this integrated active capping system can effectively block the release of target pollutants into the upper-layer water and remove the compounds from the environment.

  18. Practical remediation of the PCB-contaminated soils

    OpenAIRE

    Ido, Akiko; Niikawa, Miki; Ishihara, Shinji; Sawama, Yoshinari; Nakanishi, Tsuyoshi; Monguchi, Yasunari; Sajiki, Hironao; Nagase, Hisamitsu

    2015-01-01

    A practical method for the elimination of PCBs from PCB-contaminated soil has been developed by the combination of Soxhlet extraction using a newly-developed modified Soxhlet extractor possessing an outlet valve on the extraction chamber with the chemical degradation. Various types of PCBs contaminated in soils could be completely extracted in refluxing hexane, and the subsequent hydrodechlorination could also be completed within 1 h in a hexane–MeOH (1 : 5) solution in the presence of Pd/C a...

  19. Evaluation of remediation techniques in soils affected by residual contamination with heavy metals and arsenic.

    Science.gov (United States)

    García-Carmona, M; Romero-Freire, A; Sierra Aragón, M; Martínez Garzón, F J; Martín Peinado, F J

    2017-04-15

    Residual soil pollution from the Aznalcóllar mine spill is still a problem in some parts of the affected area, today converted in the Guadiamar Green Corridor. Dispersed spots of polluted soils, identified by the absence of vegetation, are characterized by soil acid pH and high concentrations of As, Pb, Cu and Zn. Ex situ remediation techniques were performed with unrecovered soil samples. Landfarming, Composting and Biopiles techniques were tested in order to immobilize pollutants, to improve soil properties and to promote vegetation recovery. The effectiveness of these techniques was assessed by toxicity bioassays: Lactuca sativa L. root elongation test, Vibrio fischeri bioluminescence reduction test, soil induced respiration test, and Eisenia andrei survival and metal bioaccumulation tests. Landfarming and Composting were not effective techniques, mainly due to the poor improvement of soil properties which maintained high soluble concentrations of Zn and Cu after treatments. Biopile technique, using adjacent recovered soils in the area, was the most effective action in the reduction of soil toxicity; the improvement of soil properties and the reduction in pollutants solubility were key to improve the response of the tested organisms. Therefore, the mixture of recovered soils with polluted soils in the areas affected by residual contamination is considered a more suitable technique to reduce the residual pollution and to promote the complete soil recovery in the Guadiamar Green Corridor. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Former DDT factory in Pakistan revisited for remediation: severe DDT concentrations in soils and plants from within the area.

    Science.gov (United States)

    Younas, Asma; Hilber, Isabel; ur Rehman, Shafique; Khwaja, Mahmood; Bucheli, Thomas D

    2013-04-01

    A factory in Amman Garh near Nowshera, Khyber Pakhtunkhwa, Pakistan, produced dichlorodiphenyltrichloroethane (DDT) from 1963-1994. Consequently, earlier papers reported a soil contamination in the per mille range inside the former factory wall (88 m × 106 m) and up to 10 mg/kg of DDT in the surroundings in 2005-2007. The site within the factory wall was remonitored systematically in 2011 to complement the earlier data as a prerequisite for remediation, to put them in exposure context in a population developing area, and to suggest and evaluate the optimal remediation technique for the site. The contamination was drastically higher than the earlier published data, and the sum of DDT and its metabolites (ΣDDT) was up to 65% in the soil. Grasses, shrubs, and trees growing in this severely contaminated site had 50-450 mg/kgdw of ΣDDT. Thus, people living nearby and husbandry as well as wild animals are heavily exposed to DDT. The semiarid climate favors wind drift and deposition of the pollutant. Additionally, DDT from products of herbivore animals feeding on the contaminated plants will enter the food web. To overcome the exposure and distribution of the DDT, the site within the factory wall was capped with 1.5 m of soil. This remediation technique represents the easiest and least expensive solution. Nevertheless, DDT can still evaporate or leach, and groundwater can rise in this flood-prone area and thereby become contaminated, especially because a binding layer is missing.

  1. Perspectives of humic substances application in remediation of highly heavy metals contaminated soils in Kola Subarctic

    Science.gov (United States)

    Tregubova, Polina; Turbaevskaya, Valeria; Zakharenko, Andrey; Kadulin, Maksim; Smirnova, Irina; Stepanov, Andrey; Koptsik, Galina

    2016-04-01

    Northwestern part of Russia, the Kola Peninsula, is one of the most heavy metals (HM) contaminated areas in the northern hemisphere. The main polluters, mining-and-metallurgical integrated works "Pechenganikel" and "Severonikel", are surrounded by heavily damaged barren lands that require remediation. The main contaminating metals are Ni and Cu. Using of exogenous humic substances could be possible effective and cost-efficient solution of HM contamination problem. Rational application of humates (Na-K salts of humic acids) can result in improvement of soil properties, localization of contamination and decreasing bioavailability through binding HM in relatively immobile organic complexes. Our research aim was to evaluate the influence of increasing doses of different origin humates on i) basic properties of contaminated soils; ii) mobility and bioavailability of HMs; iii) vegetation state and chemistry. In summer 2013 a model field experiment was provided in natural conditions of the Kola Peninsula. We investigated the Al-Fe-humus abrazem, soil type that dominates in technogenic barren lands around the "Severonikel" work. These soils are strongly acid: pHH2O was 3.7-4.1; pHKCl was 3.4-4.0. The exchangeable acidity is low (0.8-1.6 cmol(+)/kg) due to the depletion of fine particles and organic matter, being the carriers of exchange positions. The abrazems of barrens had lost organic horizon. 12 sites were created in 1 km from the work. In those sites, except 2 controls, various amendments were added: i) two different by it's origin types of humates: peat-humates and coal-humates, the last were in concentrations 0.5% and 1%; ii) lime; iii) NPK-fertilizer; iv) biomates (organic degradable cover for saving warm and erosion protection). As a test-culture a grass mixture with predominance of Festuca rubra and Festuca ovina was sowed. As a result we concluded that humates of different origin have unequal influence on soil properties and cause decreasing as well as

  2. 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.

  3. Selection of surfactant in remediation of DDT-contaminated soil by comparison of surfactant effectiveness.

    Science.gov (United States)

    Guo, Ping; Chen, Weiwei; Li, Yueming; Chen, Tao; Li, Linhui; Wang, Guanzhu

    2014-01-01

    With an aim to select the most appropriate surfactant for remediation of DDT-contaminated soil, the performance of nonionic surfactants Tween80, TX-100, and Brij35 and one anionic surfactant sodium dodecyl benzene sulfonate (SDBS) in enhancement of DDT water solubility and desorption of DDT from contaminated soil and their adsorption onto soil and ecotoxicities were investigated in this study. Tween80 had the highest solubilizing and soil-washing ability for DDT among the four experimental surfactants. The adsorption loss of surfactants onto soil followed the order of TX-100 > Tween80 > Brij35 > SDBS. The ecotoxicity of Tween80 to ryegrass (Lolium perenne L.) was lowest. The overall performance considering about the above four aspects suggested that Tween80 should be selected for the remediation of DDT-contaminated soil, because Tween80 had the greatest solubilizing and soil-washing ability for DDT, less adsorption loss onto soil, and the lowest ecotoxicity in this experiment.

  4. Remediation of trichloroethylene-contaminated soils by star technology using vegetable oil smoldering.

    Science.gov (United States)

    Salman, Madiha; Gerhard, Jason I; Major, David W; Pironi, Paolo; Hadden, Rory

    2015-03-21

    Self-sustaining treatment for active remediation (STAR) is an innovative soil remediation approach based on smoldering combustion that has been demonstrated to effectively destroy complex hydrocarbon nonaqueous phase liquids (NAPLs) with minimal energy input. This is the first study to explore the smoldering remediation of sand contaminated by a volatile NAPL (trichloroethylene, TCE) and the first to consider utilizing vegetable oil as supplemental fuel for STAR. Thirty laboratory-scale experiments were conducted to evaluate the relationship between key outcomes (TCE destruction, rate of remediation) to initial conditions (vegetable oil type, oil: TCE mass ratio, neat versus emulsified oils). Several vegetable oils and emulsified vegetable oil formulations were shown to support remediation of TCE via self-sustaining smoldering. A minimum concentration of 14,000 mg/kg canola oil was found to treat sand exhibiting up to 80,000 mg/kg TCE. On average, 75% of the TCE mass was removed due to volatilization. This proof-of-concept study suggests that injection and smoldering of vegetable oil may provide a new alternative for driving volatile contaminants to traditional vapour extraction systems without supplying substantial external energy.

  5. Improving petroleum contaminated land remediation decision-making through the MCA weighting process.

    Science.gov (United States)

    Balasubramaniam, Anopama; Boyle, Alexander Rohan; Voulvoulis, Nikolaos

    2007-01-01

    Internationally petroleum contamination is widespread, posing serious environmental risks including surface and groundwater contamination, thus remediation is essential. The implementation of remediation options is becoming more complex with the increasing influence of stakeholders on the outcome of decision-making processes. Acceptance of remediation schemes during implementation can be increased by involving stakeholders and the public in the decision-making stage. In petroleum remediation involving multiple stakeholders, Multicriteria Analysis has been employed due to its ability to incorporate the preferences of each stakeholder through weighting. The research focused on investigating ways to improve the weighting process. The study demonstrated the utility of SWING, and determined which type of participant and how many participants to include in the decision process, through the application of ELECTRE III and Weighted Summation. It was recommended that a mixture of stakeholders, the public and experts be involved. The total number of participants will be limited by the choice of participatory and weighting methods. The careful selection of participants, as well as the choice of participatory and weighting methods, can minimize the subjectivity involved in MCA weighting, thereby lending decisions in petroleum remediation greater legitimacy.

  6. Best Practices for Fuel System Contamination Detection and Remediation

    Science.gov (United States)

    2015-12-14

    metal content greater than 100 ppm is not normal. Most metals are below detection limits or below 50 ppb when measured by ICP-OES, (Inductively Coupled...Plasma-Optical Emission Spectroscopy). Measuring metal content of 10 ppb or lower concentration requires extreme measures to avoid contamination...formal conference with organized presentations might be the preferred, an online user group could perhaps perform the same function with faster

  7. Biological remediation of oil contaminated soil with earthworms Eisenia andrei

    Science.gov (United States)

    Chachina, S. B.; Voronkova, N. A.; Baklanova, O. N.

    2017-08-01

    The study was performed on the bioremediation efficiency of the soil contaminated with oil (20 to 100 g/kg), petroleum (20 to 60 g/kg) and diesel fuel (20 to 40 g/kg) with the help of earthworms E. andrei in the presence of bacteria Pseudomonas, nitrogen fixing bacteria Azotobacter and Clostridium, yeasts Saccharomyces, fungi Aspergillus and Penicillium, as well as Actinomycetales, all being components of biopreparation Baykal-EM. It was demonstrated that in oil-contaminated soil, the content of hydrocarbons decreased by 95-97% after 22 weeks in the presence of worms and bacteria. In petroleum-contaminated soil the content of hydrocarbons decreased by 99% after 22 weeks. The presence of the diesel fuel in the amount of 40 g per 1 kg soil had an acute toxic effect and caused the death of 50 % earthworm species in 14 days. Bacteria introduction enhanced the toxic effect of the diesel fuel and resulted in the death of 60 % earthworms after 7 days.

  8. Screening of contaminants in Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, B.G.; Frank, M.L.; Hoffman, F.O.; Hook, L.A.; Suter, G.W.; Watts, J.A.

    1992-09-01

    The purpose of this report is to present the results of a health risk and ecological risk screening analysis for Waste Area Grouping 2 (WAG 2) using available data to identify contaminants and environmental pathways that will require either further investigation or immediate consideration for remediation based on the screening indices. The screening analysis will also identify contaminants that can be assigned a low priority for further investigation and those that require additional data.

  9. Responding to biological incidents--what are the current issues in remediation of the contaminated environment?

    Science.gov (United States)

    Pottage, T; Goode, E; Wyke, S; Bennett, A M

    2014-11-01

    Since 2000 there have been a number of biological incidents resulting in environmental contamination with Bacillus anthracis, the causative agent of anthrax. These incidents include the US anthrax attacks in 2001, the US and UK drumming incidents in 2006-2008 and more recently, anthrax contamination of heroin in 2009/2010 and 2012/2013. Remediation techniques used to return environments to normal have varied between incidents, with different decontamination technologies being employed. Many factors need to be considered before a remediation strategy or recovery option can be implemented, including; cost, time (length of application), public perception of risk, and sampling strategies (and results) to name a few. These incidents have demonstrated that consolidated guidance for remediating biologically contaminated environments in the aftermath of a biological incident was required. The UK Recovery Handbook for Biological Incidents (UKRHBI) is a project led by Public Health England (PHE), formerly the Health Protection Agency (HPA) to provide guidance and advice on how to remediate the environment following a biological incident or outbreak of infection, and is expected to be published in 2015. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  10. Phytoremediation: role of terrestrial plants and aquatic macrophytes in the remediation of radionuclides and heavy metal contaminated soil and water.

    Science.gov (United States)

    Sharma, Sunita; Singh, Bikram; Manchanda, V K

    2015-01-01

    significantly raised the amount of heavy metals and radionuclides in it. Also, these activities are continuously increasing the area of the contaminated sites. In this context, an attempt has been made to review different modes of the phytoremediation and various terrestrial and aquatic plants which are being used to remediate the heavy metals and radionuclide-contaminated soil and aquatic systems. Natural and synthetic enhancers, those hasten the process of metal adsorption/absorption by plants, are also discussed. The article includes 216 references.

  11. Mapping the Sea Floor of the Historic Area Remediation Site (HARS) Offshore of New York City

    Science.gov (United States)

    Butman, Bradford

    2002-01-01

    The area offshore of New York City has been used for the disposal of dredged material for over a century. The area has also been used for the disposal of other materials such as acid waste, industrial waste, municipal sewage sludge, cellar dirt, and wood. Between 1976 and 1995, the New York Bight Dredged Material Disposal Site, also known as the Mud Dump Site (MDS), received on average about 6 million cubic yards of dredged material annually. In September 1997 the MDS was closed as a disposal site, and it and the surrounding area were designated as the Historic Area Remediation Site (HARS). The sea floor of the HARS, approximately 9 square nautical miles in area, currently is being remediated by placing a minimum 1-m-thick cap of clean dredged material on top of the surficial sediments that are contaminated from previous disposal of dredged and other materials. The U.S. Geological Survey (USGS) is working cooperatively with the U.S. Army Corps of Engineers (USACE) to map the sea floor geology of the HARS and changes in the characteristics of the surficial sediments over time.

  12. A calcite permeable reactive barrier for the remediation of Fluoride from spent potliner (SPL) contaminated groundwater

    DEFF Research Database (Denmark)

    Turner, B.D.; Binning, Philip John; Sloan, S.W.

    2008-01-01

    The use of calcite (CaCO3) as a substrate for a permeable reactive barrier (PRB) for removing fluoride from contaminated groundwater is proposed and is illustrated by application to groundwater contaminated by spent potliner leachate (SPL), a waste derived from the aluminium smelting process....... The paper focuses on two issues in the implementation of calcite permeable reactive barriers for remediating fluoride contaminated water: the impact of the groundwater chemical matrix and CO2 addition on fluoride removal. Column tests comparing pure NaF solutions, synthetic SPL solutions, and actual SPL...... leachate indicate that the complex chemical matrix of the SPL leachate can impact fluoride removal significantly. For SPL contaminant mixtures, fluoride removal is initially less than expected from idealized, pure, solutions. However, with time, the effect of other contaminants on fluoride removal...

  13. Remediation of plants contaminated with cesium by aqueous cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Osada, N., E-mail: naoyuki.osada@qse.tohoku.ac.jp [Department of Quantum Science and Energy Engineering, School of Engineering, Tohoku University, Aoba-ku, Aramaki Aza-Aoba 01, Sendai 980-8579 (Japan); Ishii, K.; Matsuyama, S.; Sugai, H.; Kusano, K.; Nozawa, Y.; Yamauchi, S.; Karahashi, M.; Oshikawa, S.; Kikuchi, K.; Koshio, S.; Watanabe, K.; Itoh, S. [Department of Quantum Science and Energy Engineering, School of Engineering, Tohoku University, Aoba-ku, Aramaki Aza-Aoba 01, Sendai 980-8579 (Japan); Suzuki, Y. [Graduate School of Biomedical Engineering, Tohoku University, Aoba-ku, Aramaki Aza-Aoba 01, Sendai 980-8579 (Japan); Terakawa, A.; Kikuchi, Y.; Fujishiro, F.; Ishizaki, A.; Arai, H. [Department of Quantum Science and Energy Engineering, School of Engineering, Tohoku University, Aoba-ku, Aramaki Aza-Aoba 01, Sendai 980-8579 (Japan)

    2014-01-01

    Aqueous cleaning removed two-thirds of the radioactivity from cesium-contaminated plants. Instead of being transferred to the water, cesium was attached to particles of rice straw. These particles were analyzed by micro-PIXE to determine the surface distribution of several elements. The elemental ratio of cesium to silicon was constant, and both elements exhibited similar distributions, suggesting that cesium was bound nonrandomly to silicon on the surface of the rice straw. Thus, aqueous cleaning removed both cesium and silicon simultaneously.

  14. An outline of a model-based expert system to identify optimal remedial strategies for restoring contaminated acquatic ecosystems: The project ``moira``

    Energy Technology Data Exchange (ETDEWEB)

    Appelgren, A.; Bergstrom, U. [Studsvik Eco and AB, Nykoping (Sweden); Brittain, J. [Oslo Univ. (Norway). LFI Zoological Museum; Gallego Diaz, E. [Madrid Universidad Politecnica (Spain). Dept. de Ingenieria Nuclear; Hakanson, L. [KEMA Nuclear, Arnhem (Niger); Monte, L. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dip. Ambiente

    1996-10-01

    The present report describes the fundamental principles of the research programme MOIRA (a model based computerized system for management support to Identify optimal remedial strategies for Restoring radionuclide contaminated Aquatic ecosystems and drainage areas) financed by the EC (European Community) (Contract N F14P-CT96-0036). The interventions to restore radionuclides contaminated aquatic systems may result in detrimental ecological, social and economical effects. Decision makers must carefully evaluate these impacts. The main aim of the MOIRA project is the development of an expert system based on validated models predicting the evolution of the radioactive contamination of fresh water systems following countermeasure applications and their relevant ecological, social and economical impacts. The expert system will help decision makers, that are not necessarily gifted with experience in environmental modeling, to identify optimal remedial strategies for restoring contaminated fresh water systems.

  15. Assessment of a remediation technique using the replacement of contaminated soils in kitchen gardens nearby a former lead smelter in Northern France.

    Science.gov (United States)

    Douay, F; Roussel, H; Pruvot, C; Loriette, A; Fourrier, H

    2008-08-15

    Vegetables cultivated in kitchen gardens that are strongly contaminated by heavy metals (Pb, Cd) may represent to consumers a means of exposure to these metals. This exposure is more problematic for those families that include a large quantity of home-grown vegetables in their diet. Researchers have shown that the majority of vegetables produced in kitchen gardens in the vicinity of the Metaleurop Nord smelter (Northern France) do not conform to European regulations. This study was carried out in three of these kitchen gardens. The concentrations of Cd and Pb in the topsoils were up to 24 and 3300 mg kg(-1) respectively. The method consisted of delineating a surface area of about 50 to 100 m(2) for each garden, then removing the contaminated soil and replacing it with a clean one. Seven species of vegetables were cultivated from 2003 to 2005 in the original contaminated soils and the remediated ones. The data showed a clear improvement of the quality of the vegetables cultivated in remediated soils, although 17% of them were still over the European legislative limits for foodstuffs. This suggested that there was a foliar contamination due to contaminated dust fallout coming from the closed smelter site and the adjacent polluted soils. In addition, the measurement of the Cd and Pb concentrations in the dust fallout showed that the substantial rise in metal concentrations in the remediated soil was not only due to atmospheric fallout. These results raise questions about possible technical, economic and sociological problems associated with this kind of remediation.

  16. The Research of Nanoparticle and Microparticle Hydroxyapatite Amendment in Multiple Heavy Metals Contaminated Soil Remediation

    Directory of Open Access Journals (Sweden)

    Zhangwei Li

    2014-01-01

    Full Text Available It was believed that when hydroxyapatite (HAP was used to remediate heavy metal-contaminated soils, its effectiveness seemed likely to be affected by its particle size. In this study, a pot trial was conducted to evaluate the efficiency of two particle sizes of HAP: nanometer particle size of HAP (nHAP and micrometer particle size of HAP (mHAP induced metal immobilization in soils. Both mHAP and nHAP were assessed for their ability to reduce lead (Pb, zinc (Zn, copper (Cu, and chromium (Cr bioavailability in an artificially metal-contaminated soil. The pakchoi (Brassica chinensis L. uptake and soil sequential extraction method were used to determine the immobilization and bioavailability of Pb, Zn, Cu, and Cr. The results indicated that both mHAP and nHAP had significant effect on reducing the uptake of Pb, Zn, Cu, and Cr by pakchoi. Furthermore, both mHAP and nHAP were efficient in covering Pb, Zn, Cu, and Cr from nonresidual into residual forms. However, mHAP was superior to nHAP in immobilization of Pb, Zn, Cu, and Cr in metal-contaminated soil and reducing the Pb, Zn, Cu, and Cr utilized by pakchoi. The results suggested that mHAP had the better effect on remediation multiple metal-contaminated soils than nHAP and was more suitable for applying in in situ remediation technology.

  17. Remediation of mercury contaminated saltwater with functionalized silica coated magnetite nanoparticles.

    Science.gov (United States)

    Mohmood, Iram; Lopes, Cláudia B; Lopes, Isabel; Tavares, Daniela S; Soares, Amadeu M V M; Duarte, Armando C; Trindade, Tito; Ahmad, Iqbal; Pereira, Eduarda

    2016-07-01

    The study aimed to evaluate the efficiency of dithiocarbamate functionalized silica coated magnetite nanoparticles (NPs) for Hg decontamination of saltwater either contaminated with Hg alone or with As and Cd. For this, the residual levels of Hg in seawater were assessed and Hg-contaminated or Hg+As+Cd-contaminated seawater toxicity to aquatic biota, before and after the sorption process, was compared. The results showed that under highly competitive conditions (water salts, Cd and As), the removal of Hg from seawater, by using these magnetic NPs, for the lowest concentration (50μg/L) was superior to 98% and for the highest concentration (500μg/L) ranged between 61% to 67%. Despite the great affinity of the magnetic NPs for Hg, they were not effective at removing As and Cd from seawater. In relation to the ecotoxicity endpoints after remediation, the mixture with lower Hg concentration exhibited no toxicity to rotifer Brachionus plicatilis and bacteria Vibrio fischeri ; however, the mixture with higher concentration revealed toxicity. In addition, the toxicity of bacteria V. fischeri, rotifer B. plicatilis and algae Phaeodactylum tricornutum, whose responses where inhibited during its exposure to the non-remediate sample was considerably reduced after treatment with NPs. Furthermore, microalgae P. tricornutum appears to be most sensitive species while Artemia franciscana showed no toxic effects to the tested solutions. Both chemical and ecotoxicological approaches revealed a high efficiency for the remediation of Hg-contaminated saltwater.

  18. 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.

  19. Ricinus communis L. A Value Added Crop for Remediation of Cadmium Contaminated Soil.

    Science.gov (United States)

    Bauddh, Kuldeep; Singh, Kripal; Singh, Rana P

    2016-02-01

    Heavy metal pollution of soil is a global environmental problem and therefore its remediation is of paramount importance. Cadmium (Cd) is a potential toxicant to living organisms and even at very low concentrations. This study was aimed to assess the effectiveness of Ricinus communis for remediation of Cd contaminated soils. For this, growth and biomass of R. communis and Cd accumulation, translocation and partitioning in different plant parts were investigated after 8 months of plant growth in Cd contaminated soil (17.50 mg Cd kg−1 soil). Eight months old plants stabilized 51 % Cd in its roots and rest of the metal was transferred to the stem and leaves. There were no significant differences in growth, biomass and yield between control and Cd treated plants, except fresh weight of shoots. The seed yield per plant was reduced only by 5 % of Cd contaminated plants than control. The amount of Cd translocated to the castor seeds was nominal i.e. 0.007 µg Cd g−1 seeds. The bioconcentration factor reduced significantly in shoots and seeds in comparison to roots. The data indicates that R. communis is highly tolerant to Cd contamination and can be used for remediation of heavy metal polluted sites.

  20. Sequential Remediation Processes for Effective Removal of Oil from Contaminated Soils

    Directory of Open Access Journals (Sweden)

    Deepika Dave

    2011-01-01

    Full Text Available Problem statement: Over 2.2 billions of oil and oil products are transported every year and often these activities can result in air, water and soil contamination. Expousure to petroleum products can cause health problems to humn and animals and affect marine animals and wildlife habitats. Approach: The objective of this study was to develop a technology for the remediation of soil contaminated with petroleum hydrocarbons. The remediation method included three processes: (a an effective soil washing process for the removal of the hydrocarbons from the contaminated soil, (b an efficient water decontamination process using peat moss as an oil absorbent and (c an effective bioremediation process for converting the oil in peat moss into carbon dioxide and water. Results: The results showed that water is an effective solvent for the removal of oil from contaminated soil. It has also been determined that peat moss is an effective absorbent and could be used to remove oil from the contaminated water. Peat can absorb 12.6 times its weight liquid (water/oil. The bioremediation process was effective in degrading the oil into harmless carbon dioxide and water products. About 77.65% of the THC was removed within 60 days of bioremediation. The hemophilic microbial population in the compost quickly acclimatized to the hydrocarbon as was evident from the immediate rise in the reactor temperature. The C: N ratio decreased from 30:1-12:1 indicating the degradation of organic C in the petroleum hydrocarbons and the peat. Urea was a very effective source of nitrogen in initiating and maintaining intense microbial respiration activity. Conclusion: A sequential processes for the remediation of oil contaminated soil was developed. These included soil washing, absorption of oil from water using peat and bioremediation of contaminated peat. A degradation model was developed and used to calculate the time required for a complete degradation. The model indicated that a

  1. Evaluation of the effectiveness and salt stress of Pteris vittata in the remediation of arsenic contamination caused by tsunami sediments.

    Science.gov (United States)

    Sugawara, Kazuki; Kobayashi, Akihiro; Endo, Ginro; Hatayama, Masayoshi; Inoue, Chihiro

    2014-01-01

    On March 11, 2011, one of the negative effects of the tsunami phenomenon that devastated the Pacific coast of the Tohoku district in Japan was the deposition of a wide range of arsenic (As) contamination to the soil. To remediate such a huge area of contamination, phytoremediation by Pteris vittata, an As-hyperaccumulator, was considered. To evaluate the efficacy of applying P. vittata to the area, the salt tolerance of P. vittata and the phytoextraction of As from soil samples were investigated. For the salt tolerance test, spore germination was considerably decreased at an NaCl level of more than 100 mM. At 200 mM, the gametophytes exhibited a morphological defect. Furthermore, the growth inhibition of P. vittata was observed with a salinity that corresponded to 66.2 mS/m of electric conductivity (EC) in the soil. A laboratory phytoremediation experiment was conducted using As-contaminated soils for 166 days. P. vittata grew and accumulated As at 264 mg/kg-DW into the shoots. Consequently, the soluble As in the soil was evidently decreased. These results showed that P. vittata was applicable to the phytoremediation of As-contaminated soil with low salinity as with the contamination caused by the 2011 tsunami.

  2. 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.

  3. Chlorine dioxide remediation of a virus-contaminated manufacturing facility.

    Science.gov (United States)

    Lutgen, Mark

    2011-01-01

    CONFERENCE PROCEEDING Proceedings of the PDA/FDA Adventitious Viruses in Biologics: Detection and Mitigation Strategies Workshop in Bethesda, MD, USA; December 1-3, 2010 Guest Editors: Arifa Khan (Bethesda, MD), Patricia Hughes (Bethesda, MD) and Michael Wiebe (San Francisco, CA) Chlorine dioxide fumigation was successfully used to decontaminate a virally contaminated biotech manufacturing facility. Addressing safety, product quality, and corrosion risks were important factors in planning the building fumigation. Studies were performed to define the conditions in which minute mouse virus (MMV) is inactivated by chlorine dioxide and to understand equipment and facility risks. Written plans and procedures documented activities necessary to safely fumigate the building and requalify it to manufacture commercial product.

  4. Remediation of metal-contaminated urban soil using flotation technique.

    Science.gov (United States)

    Dermont, G; Bergeron, M; Richer-Laflèche, M; Mercier, G

    2010-02-01

    A soil washing process using froth flotation technique was evaluated for the removal of arsenic, cadmium, copper, lead, and zinc from a highly contaminated urban soil (brownfield) after crushing of the particle-size fractions >250microm. The metal contaminants were in particulate forms and distributed in all the particle-size fractions. The particle-by-particle study with SEM-EDS showed that Zn was mainly present as sphalerite (ZnS), whereas Cu and Pb were mainly speciated as various oxide/carbonate compounds. The influence of surfactant collector type (non-ionic and anionic), collector dosage, pulp pH, a chemical activation step (sulfidization), particle size, and process time on metal removal efficiency and flotation selectivity was studied. Satisfactory results in metal recovery (42-52%), flotation selectivity (concentration factor>2.5), and volume reduction (>80%) were obtained with anionic collector (potassium amyl xanthate). The transportation mechanisms involved in the separation process (i.e., the true flotation and the mechanical entrainment) were evaluated by the pulp chemistry, the metal speciation, the metal distribution in the particle-size fractions, and the separation selectivity indices of Zn/Ca and Zn/Fe. The investigations showed that a great proportion of metal-containing particles were recovered in the froth layer by entrainment mechanism rather than by true flotation process. The non-selective entrainment mechanism of the fine particles (flotation selectivity drop, especially with a long flotation time (>5 min) and when a high collector dose is used. The intermediate particle-size fraction (20-125 microm) showed the best flotation selectivity. Copyright 2009 Elsevier B.V. All rights reserved.

  5. Effect of electrokinetic remediation on indigenous microbial activity and community within diesel contaminated soil.

    Science.gov (United States)

    Kim, Seong-Hye; Han, Hyo-Yeol; Lee, You-Jin; Kim, Chul Woong; Yang, Ji-Won

    2010-07-15

    Electrokinetic remediation has been successfully used to remove organic contaminants and heavy metals within soil. The electrokinetic process changes basic soil properties, but little is known about the impact of this remediation technology on indigenous soil microbial activities. This study reports on the effects of electrokinetic remediation on indigenous microbial activity and community within diesel contaminated soil. The main removal mechanism of diesel was electroosmosis and most of the bacteria were transported by electroosmosis. After 25 days of electrokinetic remediation (0.63 mA cm(-2)), soil pH developed from pH 3.5 near the anode to pH 10.8 near the cathode. The soil pH change by electrokinetics reduced microbial cell number and microbial diversity. Especially the number of culturable bacteria decreased significantly and only Bacillus and strains in Bacillales were found as culturable bacteria. The use of EDTA as an electrolyte seemed to have detrimental effects on the soil microbial activity, particularly in the soil near the cathode. On the other hand, the soil dehydrogenase activity was enhanced close to the anode and the analysis of microbial community structure showed the increase of several microbial populations after electrokinetics. It is thought that the main causes of changes in microbial activities were soil pH and direct electric current. The results described here suggest that the application of electrokinetics can be a promising soil remediation technology if soil parameters, electric current, and electrolyte are suitably controlled based on the understanding of interaction between electrokinetics, contaminants, and indigenous microbial community.

  6. New Pump and Treat Facility Remedial Action Work Plan For Test Area North Final Groundwater Remediation, Operable Unit 1-07B

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, L. O.

    2007-06-12

    This remedial action work plan identifies the approach and requirements for implementing the medial zone remedial action for Test Area North, Operable Unit 1-07B, at the Idaho National Laboratory. This plan details the management approach for the construction and operation of the New Pump and Treat Facility (NPTF). As identified in the remediatial design/remedial action scope of work, a separate remedial design/remedial action work plan will be prepared for each remedial component of the Operable Unit 1-07B remedial action.

  7. Biological assessment for the remedial action at the chemical plant area of the Weldon Spring site

    Energy Technology Data Exchange (ETDEWEB)

    Hlohowskyj, I.; Dunn, C.P.

    1992-11-01

    The Weldon Spring site in St.Charles County, Missouri, became contaminated during the 1940s through the 1960s as a result of explosives production by the US Army and uranium and thorium processing by the predecessor agency of the US Department of Energy (DOE). The site is listed on the National Priorities List of the US Environmental Protection Agency, and DOE is responsible for its cleanup. Contaminants are present in soil, surface water, and aquatic sediments. Alternatives identified for site remediation are no action (included as baseline for comparison), treatment and disposal of the wastes at the Weldon Spring site, and on-site treatment followed by off-site disposal at either a commercial facility near Clive, Utah, or at DOE`s Hanford site near Richland, Washington. In accordance with the requirements of the Endangered Species Act, this biological assessment has been prepared to evaluate the potential effects of proposed remedial action alternatives on federal listed (endangered or threatened) and candidate species at the respective sites. The assessment includes consideration of the environmental setting at each site; the federal listed and candidate species that could occur at each site; the construction, excavation, and treatment activities under each alternative; and the amount of land area affected at each site.

  8. Biological assessment for the remedial action at the chemical plant area of the Weldon Spring site

    Energy Technology Data Exchange (ETDEWEB)

    Hlohowskyj, I.; Dunn, C.P.

    1992-11-01

    The Weldon Spring site in St.Charles County, Missouri, became contaminated during the 1940s through the 1960s as a result of explosives production by the US Army and uranium and thorium processing by the predecessor agency of the US Department of Energy (DOE). The site is listed on the National Priorities List of the US Environmental Protection Agency, and DOE is responsible for its cleanup. Contaminants are present in soil, surface water, and aquatic sediments. Alternatives identified for site remediation are no action (included as baseline for comparison), treatment and disposal of the wastes at the Weldon Spring site, and on-site treatment followed by off-site disposal at either a commercial facility near Clive, Utah, or at DOE's Hanford site near Richland, Washington. In accordance with the requirements of the Endangered Species Act, this biological assessment has been prepared to evaluate the potential effects of proposed remedial action alternatives on federal listed (endangered or threatened) and candidate species at the respective sites. The assessment includes consideration of the environmental setting at each site; the federal listed and candidate species that could occur at each site; the construction, excavation, and treatment activities under each alternative; and the amount of land area affected at each site.

  9. Enhanced electrokinetic remediation of fluorine-contaminated soil by applying an ammonia continuous circulation system

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Shufa; Zhou, Ming; Zhang, Shuangyan [Henan University of Science and Technology, Luoyang (China)

    2016-02-15

    The objective of this research was to investigate the effects of ammonia continuous circulation enhanced electrokinetic remediation of fluorine contaminated soil and to analyze its influence on soil pH after remediation. An experimental study was carried out in self-made electrokinetic apparatus. The voltage gradient was set at 1.0V/cm and ammonia water with different concentrations was used as electrolyte which circulated in series. Comparative studies were made by using deionized water as electrolyte which circulated separately in one experiment and continuously in another. According to the experiment the continuous circulation of ammonia water increased the current value during the remediation process and maintained current through the soil cell stabler, which not only increased fluorine migration but also reduced energy consumption. Among the given ammonia concentrations (0, 0.01, 0.1 and 0.2mol/L) the removal rate increased with ammonia concentration. 0.2mol/L had the highest current (26.8mA), and the removal rate amounted up to 57.3%. By using ammonia circulation enhanced electrokinetic technology, the difference between pH values of cathode soil and anode soil became smaller. Ammonia continuous circulation enhanced electrokinetics can effectively remediate fluorine contaminated soil and the residual ammonia in the soil can also improve soil fertility.

  10. Quality Assurance Plan for the remedial investigation of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, G.P.; Miller, D.E. (Automated Sciences Group, Inc., Oak Ridge, TN (United States))

    1992-12-01

    The Oak Ridge National Laboratory (ORNL) Waste Area Grouping (WAG) 2 Site Investigation (SI)includes the lower portion of the White Oak Creek (WOC) drainage and enbayment, and associated floodplain and subsurface environment. The ORNL main plant and the major waste storage and disposal facilities at ORNL are located in the WOC watershed and are drained by the WOC system to the Clinch River, located off-site. Environmental media are contaminated and continue to receive contaminants from hydrologically upgradient WAGS. WAG 2 is important as a conduit from upgradient areas to the Clinch River. The general objectives of the WAG 2 SI Project are to conduct a multimedia monitoring and characterization program to define and monitor the input of contaminants from adjacent WAGS, monitor and gather sufficient information for processes controlling or driving contaminant fluxes to construct an appropriate conceptual model for WAG 2, and prepare for the eventual remediation of WAG 2.

  11. Microbial fuel cell driving electrokinetic remediation of toxic metal contaminated soils.

    Science.gov (United States)

    Habibul, Nuzahat; Hu, Yi; Sheng, Guo-Ping

    2016-11-15

    An investigation of the feasibility of in-situ electrokinetic remediation for toxic metal contaminated soil driven by microbial fuel cell (MFC) is presented. Results revealed that the weak electricity generated from MFC could power the electrokinetic remediation effectively. The metal removal efficiency and its influence on soil physiological properties were also investigated. With the electricity generated through the oxidation of organics in soils by microorganisms, the metals in the soils would mitigate from the anode to the cathode. The concentrations of Cd and Pb in the soils increased gradually through the anode to the cathode regions after remediation. After about 143days and 108 days' operation, the removal efficiencies of 31.0% and 44.1% for Cd and Pb at the anode region could be achieved, respectively. Soil properties such as pH and soil conductivity were also significantly redistributed from the anode to the cathode regions. The study shows that the MFC driving electrokinetic remediation technology is cost-effective and environmental friendly, with a promising application in soil remediation.

  12. Mechanical alloying of a hydrogenation catalyst used for the remediation of contaminated compounds

    Science.gov (United States)

    Quinn, Jacqueline W. (Inventor); Clausen, Christian A. (Inventor); Geiger, Cherie L. (Inventor); Aitken, Brian S. (Inventor)

    2012-01-01

    A hydrogenation catalyst including a base material coated with a catalytic metal is made using mechanical milling techniques. The hydrogenation catalysts are used as an excellent catalyst for the dehalogenation of contaminated compounds and the remediation of other industrial compounds. Preferably, the hydrogenation catalyst is a bimetallic particle including zero-valent metal particles coated with a catalytic material. The mechanical milling technique is simpler and cheaper than previously used methods for producing hydrogenation catalysts.

  13. Remediation of metal-contaminated land for plant cultivation in the Arctic/subarctic region

    Science.gov (United States)

    Kikuchi, Ryunosuke; Gorbacheva, Tamara T.; Ferreira, Carla S.

    2017-04-01

    Hazardous activities and/or industries involve the use, storage or disposal of hazardous substances. These substances can sometimes contaminate the soil, which can remain contaminated for many years. The metals can have severe effects of on ecosystems. In the Arctic/subarctic regions, the Kola Peninsula (66-70°N and 28°30'-41°30'E) in Russia is one of the seriously polluted regions: close to the nickel-copper smelters, the deposition of metal pollutants has severely damaged the soil and ground vegetation, resulting in a desert area. An area of 10-15 km around the smelters on the Kola Peninsula is today dry sandy and stony ground. A great amount of financial aid is usually required to recover theland. Considering cost performance, a pilot-scale (4ha) field test was carried out to investigate how to apply municipal sewage sludge for rehabilitation of degraded land near the Ni-Cu smelter complex on the Kola Peninsula. The above-mentioned field test for soil rehabilitation was performed while smelting activities were going on; thus, the survey fields were suffering from pollution emitted by the metallurgical industry, and may continue to suffer in the future. After the composting of sewage sludge, the artificial substratum made from the compost was introduced to the test field for the polluted-land remediation, and then willows, birches and grasses were planted on the substratum. The following remarkable points in pollution load were observed between the background field and the rehabilitation test field (e.g. polluted land): (i) the annual precipitation amount of SO42- (5668 g/ha) in the rehabilitation test field was over 5 times greater than that in the background field; (ii) the Pb amount (1.5 g/ha) in the rehabilitation test field was 29 times greater than that in the background field; (iii) the Co amount (10.9 g/ha) in the rehabilitation test field was 54 times greater than that in the background field; (iv) the Cu amount (752 g/ha) in the rehabilitation field

  14. Remediation of petroleum hydrocarbon-contaminated sites by DNA diagnosis-based bioslurping technology.

    Science.gov (United States)

    Kim, Seungjin; Krajmalnik-Brown, Rosa; Kim, Jong-Oh; Chung, Jinwook

    2014-11-01

    The application of effective remediation technologies can benefit from adequate preliminary testing, such as in lab-scale and Pilot-scale systems. Bioremediation technologies have demonstrated tremendous potential with regards to cost, but they cannot be used for all contaminated sites due to limitations in biological activity. The purpose of this study was to develop a DNA diagnostic method that reduces the time to select contaminated sites that are good candidates for bioremediation. We applied an oligonucleotide microarray method to detect and monitor genes that lead to aliphatic and aromatic degradation. Further, the bioremediation of a contaminated site, selected based on the results of the genetic diagnostic method, was achieved successfully by applying bioslurping in field tests. This gene-based diagnostic technique is a powerful tool to evaluate the potential for bioremediation in petroleum hydrocarbon contaminated soil.

  15. Remediation of oil-contaminated sand by coal agglomeration using ball milling.

    Science.gov (United States)

    Shin, Yu-Jen; Shen, Yun-Hwei

    2011-10-01

    The mechanical shear force provided by a less energy intensive device (usually operating at 20-200 rpm), a ball mill, was used toperform coal agglomeration and its effects on remediation of a model fuel oil-contaminated sand were evaluated. Important process parameters such as the amount of coal added, milling time, milling speed and the size of milling elements are discussed. The results suggested that highly hydrophobic oil-coal agglomerates, formed by adding suitable amounts of coal into the oil-contaminated sand, could be mechanically liberated from cleaned sand during ball milling and recovered as a surface coating on the steel balls. Over 90% removal of oil from oil-contaminated sand was achieved with 6 wt% of coal addition and an optimum ball milling time of 20 min and speed of 200 rpm. This novel process has considerable potential for cleaning oil-contaminated sands.

  16. Soil washing as a potential remediation technology for contaminated DOE sites

    Energy Technology Data Exchange (ETDEWEB)

    Devgun, J.S.; Beskid, N.J. [Argonne National Lab., IL (United States); Natsis, M.E. [Princeton Univ., NJ (United States); Walker, J.S. [USDOE, Washington, DC (United States)

    1993-03-01

    Frequently detected contaminants at US Department of Energy (DOE) sites include radionuclides, heavy metals, and chlorinated hydrocarbons. Remediation of these sites requires application of several technologies used in concert with each other, because no single technology is universally applicable. Special situations, such as mixed waste, generally require innovative technology development. This paper, however, focuses on contaminated soils, for which soil washing and vitrification technologies appear to have wide ranging application potential. Because the volumes of contaminated soils around the DOE complex are so large, soil washing can offer a potentially inexpensive way to effect remediation or to attain waste volume reduction. As costs for disposal of low-level and mixed wastes continue to rise, it is likely that volume-reduction techniques and in-situ containment techniques will become increasingly important. This paper reviews the status of the soil washing technology, examines the systems that are currently available, and discusses the potential application of this technology to some DOE sites, with a focus on radionuclide contamination and, primarily, uranium-contaminated soils

  17. Soil washing as a potential remediation technology for contaminated DOE sites

    Energy Technology Data Exchange (ETDEWEB)

    Devgun, J.S.; Beskid, N.J. (Argonne National Lab., IL (United States)); Natsis, M.E. (Princeton Univ., NJ (United States)); Walker, J.S. (USDOE, Washington, DC (United States))

    1993-01-01

    Frequently detected contaminants at US Department of Energy (DOE) sites include radionuclides, heavy metals, and chlorinated hydrocarbons. Remediation of these sites requires application of several technologies used in concert with each other, because no single technology is universally applicable. Special situations, such as mixed waste, generally require innovative technology development. This paper, however, focuses on contaminated soils, for which soil washing and vitrification technologies appear to have wide ranging application potential. Because the volumes of contaminated soils around the DOE complex are so large, soil washing can offer a potentially inexpensive way to effect remediation or to attain waste volume reduction. As costs for disposal of low-level and mixed wastes continue to rise, it is likely that volume-reduction techniques and in-situ containment techniques will become increasingly important. This paper reviews the status of the soil washing technology, examines the systems that are currently available, and discusses the potential application of this technology to some DOE sites, with a focus on radionuclide contamination and, primarily, uranium-contaminated soils

  18. Does bioleaching represent a biotechnological strategy for remediation of contaminated sediments?

    Energy Technology Data Exchange (ETDEWEB)

    Fonti, Viviana, E-mail: v.fonti@univpm.it; Dell' Anno, Antonio; Beolchini, Francesca

    2016-09-01

    Bioleaching is a consolidated biotechnology in the mining industry and in bio-hydrometallurgy, where microorganisms mediate the solubilisation of metals and semi-metals from mineral ores and concentrates. Bioleaching also has the potential for ex-situ/on-site remediation of aquatic sediments that are contaminated with metals, which represent a key environmental issue of global concern. By eliminating or reducing (semi-)metal contamination of aquatic sediments, bioleaching may represent an environmentally friendly and low-cost strategy for management of contaminated dredged sediments. Nevertheless, the efficiency of bioleaching in this context is greatly influenced by several abiotic and biotic factors. These factors need to be carefully taken into account before selecting bioleaching as a suitable remediation strategy. Here we review the application of bioleaching for sediment bioremediation, and provide a critical view of the main factors that affect its performance. We also discuss future research needs to improve bioleaching strategies for contaminated aquatic sediments, in view of large-scale applications. - Highlights: • Bioleaching may represent a sustainable strategy for contaminated dredged sediments • The performance is greatly influenced by several abiotic and biotic factors • Geochemical characteristics and metal partitioning have a key role • Sulphide minerals in the sediment are a favorable element • Microorganisms other than Fe/S oxidisers may open new perspectives.

  19. Remediation of Steel Slag on Acidic Soil Contaminated by Heavy Metal

    Institute of Scientific and Technical Information of China (English)

    Haihong; GU; Fuping; LI; Xiang; GUAN; Zhongwei; LI; Qiang; YU

    2013-01-01

    The technology of in situ immobilization with amendments is an important measure that remediates the soil contaminated by heavy metals, and selecting economical and effective amendments is the key. The effects and mechanism of steel slag, the silicon-rich alkaline byproduct which can remediate acidic soil contaminated by heavy metal, are mainly introduced in this paper to provide theory reference for future research. Firstly, the paper analyzes current research situation of in situ immobilization with amendments. Then, it introduces the main physicochemical properties of steel slag, and the effect on soil pH value as well as heavy metal activity. Besides, the paper elaborates the promoting effect on silicon-requiring plant and the strengthening mechanism for its resistant capability of heavy metal. According to the analysis, the application of steel slag could be a potential valuable strategy to remediate acidic soil contaminated by heavy metal by modifying the transformation of heavy metals in both soil and plant, so that the translocation of heavy metal in food chain is reduced.

  20. Remediation of a historically Pb contaminated soil using a model natural Mn oxide waste.

    Science.gov (United States)

    McCann, Clare M; Gray, Neil D; Tourney, Janette; Davenport, Russell J; Wade, Matthew; Finlay, Nina; Hudson-Edwards, Karen A; Johnson, Karen L

    2015-11-01

    A natural Mn oxide (NMO) waste was assessed as an in situ remediation amendment for Pb contaminated sites. The viability of this was investigated using a 10 month lysimeter trial, wherein a historically Pb contaminated soil was amended with a 10% by weight model NMO. The model NMO was found to have a large Pb adsorption capacity (qmax 346±14 mg g(-1)). However, due to the heterogeneous nature of the Pb contamination in the soils (3650.54-9299.79 mg kg(-1)), no treatment related difference in Pb via geochemistry could be detected. To overcome difficulties in traditional geochemical techniques due to pollutant heterogeneity we present a new method for unequivocally proving metal sorption to in situ remediation amendments. The method combines two spectroscopic techniques; namely electron probe microanalysis (EPMA) and X-ray photoelectron spectroscopy (XPS). Using this we showed Pb immobilisation on NMO, which were Pb free prior to their addition to the soils. Amendment of the soil with exogenous Mn oxide had no effect on microbial functioning, nor did it perturb the composition of the dominant phyla. We conclude that NMOs show excellent potential as remediation amendments. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Biomineralization based remediation of As(III) contaminated soil by Sporosarcina ginsengisoli.

    Science.gov (United States)

    Achal, Varenyam; Pan, Xiangliang; Fu, Qinglong; Zhang, Daoyong

    2012-01-30

    Arsenic is a highly toxic metalloid and has posed high risk to the environment. As(III) is highly mobile in soil and leached easily into groundwater. The current remediation techniques are not sufficient to immobilize this toxic element. In the present study, an As(III) tolerant bacterium Sporosarcina ginsengisoli CR5 was isolated from As contaminated soil of Urumqi, China. We investigated the role of microbial calcite precipitated by this bacterium to remediate soil contaminated with As(III). The bacterium was able to grow at high As(III) concentration of 50mM. In order to obtain arsenic distribution pattern, five stage soil sequential extraction was carried out. Arsenic mobility was found to significantly decrease in the exchangeable fraction of soil and subsequently the arsenic concentration was markedly increased in carbonated fraction after bioremediation. Microbially induced calcite precipitation (MICP) process in bioremediation was further confirmed by ATR-FTIR and XRD analyses. XRD spectra showed presence of various biomineralization products such as calcite, gwihabaite, aragonite and vaterite in bioremediated soil samples. The results from this study have implications that MICP based bioremediation by S. ginsengisoli is a viable, environmental friendly technology for remediation of the arsenic contaminated sites.

  2. Remediation of heavy metal contaminated soils by using Solanum nigrum: A review.

    Science.gov (United States)

    Rehman, Muhammad Zia Ur; Rizwan, Muhammad; Ali, Shafaqat; Ok, Yong Sik; Ishaque, Wajid; Saifullah; Nawaz, Muhammad Farrakh; Akmal, Fatima; Waqar, Maqsooda

    2017-09-01

    Heavy metals are among the major environmental pollutants and the accumulation of these metals in soils is of great concern in agricultural production due to the toxic effects on crop growth and food quality. Phytoremediation is a promising technique which is being considered as an alternative and low-cost technology for the remediation of metal-contaminated soils. Solanum nigrum is widely studied for the remediation of heavy metal-contaminated soils owing to its ability for metal uptake and tolerance. S. nigrum can tolerate excess amount of certain metals through different mechanism including enhancing the activities of antioxidant enzymes and metal deposition in non-active parts of the plant. An overview of heavy metal uptake and tolerance in S. nigrum is given. Both endophytic and soil microorganisms can play a role in enhancing metal tolerance in S. nigrum. Additionally, optimization of soil management practices and exogenous application of amendments can also be used to enhance metal uptake and tolerance in this plant. The main objective of the present review is to highlight and discuss the recent progresses in using S. nigrum for remediation of metal contaminated soils. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. New Pump and Treat Facility Remedial Action Work Plan for Test Area North (TAN) Final Groundwater Remediation, Operable Unit 1-07B

    Energy Technology Data Exchange (ETDEWEB)

    L. O. Nelson

    2003-09-01

    This operations and maintenance plan supports the New Pump and Treat Facility (NPTF) remedial action work plan and identifies the approach and requirements for the operations and maintenance activities specific to the final medical zone treatment remedy. The NPTF provides the treatment system necessary to remediate the medical zone portion of the OU 1-07B contaminated groundwater plume. Design and construction of the New Pump and Treat Facility is addressed in the NPTF remedial action work plan. The scope of this operation and maintenance plan includes facility operations and maintenance, remedy five-year reviews, and the final operations and maintenance report for the NPTF.

  4. Remedial investigation report on Waste Area Grouping 5 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Volume 1: Technical summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    A remedial investigation (RI) was performed to support environmental restoration activities for Waste Area Grouping (WAG) 5 at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The WAG 5 RI made use of the observational approach, which concentrates on collecting only information needed to assess site risks and support future cleanup work. This information was interpreted and is presented using the framework of the site conceptual model, which relates contaminant sources and release mechanisms to migration pathways and exposure points that are keyed to current and future environmental risks for both human and ecological receptors. The site conceptual model forms the basis of the WAG 5 remedial action strategy and remedial action objectives. The RI provided the data necessary to verify this model and allows recommendations to be made to accomplish those objectives.

  5. EXTRACTION, RECOVERY, AND BIOSTABILITY OF EDTA FOR REMEDIATION OF HEAVY METAL-CONTAMINATED SOIL. (R825549C052)

    Science.gov (United States)

    Chelation removal of heavy metals from contaminated soil is seen as a viable remediation technique. A useful chelating agent should be strong, reusable, and biostable during metal extraction and recovery operations. This work tested the extraction, recovery, and biostability o...

  6. Environmental Pathway Models-Ground-Water Modeling in Support of Remedial Decision Making at Sites Contaminated with Radioactive Material

    Science.gov (United States)

    The Joint Interagency Environmental Pathway Modeling Working Group wrote this report to promote appropriate and consistent use of mathematical environmental models in the remediation and restoration of sites contaminated by radioactive substances.

  7. EXTRACTION, RECOVERY, AND BIOSTABILITY OF EDTA FOR REMEDIATION OF HEAVY METAL-CONTAMINATED SOIL. (R825549C052)

    Science.gov (United States)

    Chelation removal of heavy metals from contaminated soil is seen as a viable remediation technique. A useful chelating agent should be strong, reusable, and biostable during metal extraction and recovery operations. This work tested the extraction, recovery, and biostability o...

  8. Remediation of oil-contaminated soil using the CLEANSOIL technology

    Science.gov (United States)

    Zakharchenko, A. V.; Korzhov, Yu. V.; Lapshina, E. D.; Kul'Kov, M. G.; Yarkov, D. M.; Khoroshev, D. I.

    2011-04-01

    Approbation data of the innovative CLEANSOIL technology of soil purification after oil pollution are given. Drainage pipes filled with an adsorbent with microorganisms placed in the soil are used. It is revealed that the content of hydrocarbons under the technological constructions (metal columns and reservoirs) rises in comparison with the open oil-polluted areas. It is shown that the oil is destroyed quicker under the constructions versus in the open areas. The microorganisms better assimilate the n-alkanes with C14 chains than the C32-40 hydrocarbons. The application of a combined technology based on the sorption and reduction of the hydrocarbons by microorganisms makes it possible to quickly reduce the soil pollution by oil products without the soil cover's disturbance.

  9. Organotin contamination in South American coastal areas.

    Science.gov (United States)

    de Castro, Italo Braga; Perina, Fernando Cesar; Fillmann, Gilberto

    2012-03-01

    Organotin compounds (OTs) were used in antifouling paints for more than four decades. However, due to their widespread intensive use and high toxicity, undesirable effects in non-target marine organisms have been detected since the early 1980s. Consequently, the International Maritime Organization banned new maritime applications of these products on January 1, 2003 and their presence on ship hulls from January 1, 2008. Although extensively studied in Europe, North America, Oceania, and Asia, environmental levels and effects of organotin contamination are still poorly known for South America. Thus, the current review aimed to present the actual status of this problem in South America by summarizing and comparing the available data in the literature. An overview of the OTs concentrations in sediment and biota and their effects, mainly imposex in marine gastropods, are presented. This work showed that in Atlantic coastal areas of South America there are "hot spots" of OTs contamination, similar to that observed in industrialized countries of Northern Hemisphere. On the other hand, the number of accomplished studies in the Pacific coast is extremely low. Despite the limitation on studies about OTs environmental levels and their related effects, the available data pointed out for a widespread TBT contamination along the South American coastal areas. Therefore, the establishment of baselines of organotin contamination in the Pacific coast and the implementation of temporal trend studies in the South American coastal areas is crucial to verify the effectiveness of local regulations and OTs global ban, and to map the most sensitive areas related to present and future antifouling impacts.

  10. The Dnieper River Aquatic System Radioactive Contamination; Long-tern Natural Attenuation And Remediation History

    Science.gov (United States)

    Voitsekhovych, Oleg; Laptev, Genadiy; Kanivets, Vladimir; Konoplev, Alexey

    2013-04-01

    Near 27 year passed after the Chernobyl Accident, and the experience gained to study radionuclide behavior in the aquatic systems and to mitigate water contamination are still pose of interest for scientists, society and regulatory austerities. There are different aspects of radionuclide transport in the environment were studied since the Chernobyl fallout in 1986 covered the river catchments, wetlands, river, lakes/reservoirs and reached the Black Sea. The monitoring time series data set and also data on the radionuclides behavior studies in the water bodies (river, lakes and the Black Sea) are available now in Ukraine and other affected countries. Its causation analyses, considering the main geochemical, physical and chemical and hydrological process, governing by radionuclide mobility and transport on the way from the initially contaminated catchments, through the river-reservoir hydrological system to the Black Sea can help in better understanding of the main factors governing be the radionuclide behavior in the environment. Radionuclide washout and its hydrological transport are determined speciation of radionuclides as well as soil types and hydrological mode and also geochemistry and landscape conditions at the affected areas. Mobility and bioavailability of radionuclides are determined by ratio of radionuclide chemical forms in fallout and site-specific environmental characteristics determining rates of leaching, fixation/remobilization as well as sorption-desorption of mobile fraction (its solid-liquid distribution). In many cases the natural attenuation processes governing by the above mentioned processes supported by water flow transportation and sedimentation played the key role in self-rehabilitation of the aquatic ecosystems. The models developed during post-Chernobyl decade and process parameters studies can help in monitoring and remediation programs planed for Fukusima Daichi affected watersheds areas as well. Some most important monitoring data

  11. Novel materials for environmental remediation of oil sands contaminants.

    Science.gov (United States)

    Wilson, Lee D; Mohamed, Mohamed H; Headley, John V

    2014-01-01

    The incorporation of β-cyclodextrin (β-CD) within the framework structure of copolymer sorbent materials, represents a novel modular design approach with significant potential for controlled tuning of the textural mesoporosity of such sorbent frameworks. β-CD copolymers represent an innovative design strategy for the development of "smart" or "functional" porous materials with improved solid phase extraction (SPE) and molecular recognition properties because of the porogen characteristics and their unique host-guest properties. Carbohydrate-based copolymers containing cyclodextrins (CDs) are of interest, in part, because of their ability to form stable inclusion complexes in aqueous solution. The inclusion properties of β-CD copolymers are determined by the surface area, pore structure, and site accessibility of inclusion sites within the copolymer framework. A mini-review of recent research in our group concerning the use of copolymers containing β-CD as sorbent materials for naphthenic acids is presented herein.

  12. Application of screening model for assessing subsurface NAPL contamination and remediation

    Energy Technology Data Exchange (ETDEWEB)

    MacFarlane, S.; Shiu, W.Y. [Univ. of Toronto, Ontario (Canada); Mackay, D. [Trent Univ., Peterborough, Ontario (Canada)

    1997-12-31

    To select the most appropriate technique for remediating non-aqueous phase liquids (NAPL)-contaminated sites a full understanding is required of the characteristics of the site, the contaminant, and the effectiveness of the remedial measure. A screening model has been developed (MacFarlane and Mackay, in press) for evaluating the partitioning of components of NAPLs present in the subsurface environment and for providing order of magnitude estimates of the effectiveness, in terms of recovery time, of a variety of remedial technologies including water and solvent flushing, air and steam stripping, and enhanced degradation. The model calculations employ the fugacity concept which is found to simplify and clarify the calculations. Two types of calculations are employed in the screening assessment. Level 1 fugacity calculations are simple multimedia equilibrium calculations that deduce how a chemical partitions between media or phases in a defined environment. Level 2 fugacity calculations account for or quantify losses of chemical being conveyed out of the environment by advective flows in phases such as air or water or by degradation by chemical or biochemical reactions. The screening model was originally applied to an existing fractured bedrock site in Smithville, Ontario which is contaminated with a NAPL containing polychlorinated biphenyls, trichlorobenzene, and trichloroethylene. In this paper, the model approach is illustrated for vinyl chloride which may be present at the site due to biochemical reactions occurring in the subsurface. It is their aim to show that this approach can provide screening level insights into the behavior and remediation of NAPLs and can serve as a first step and justification towards more detailed modeling.

  13. Metal contamination and post-remediation recovery in the Boulder River watershed, Jefferson County, Montana

    Science.gov (United States)

    Unruh, Daniel M.; Church, Stanley E; Nimick, David A.; Fey, David L.

    2009-01-01

    The legacy of acid mine drainage and toxic trace metals left in streams by historical mining is being addressed by many important yet costly remediation efforts. Monitoring of environmental conditions frequently is not performed but is essential to evaluate remediation effectiveness, determine whether clean-up goals have been met, and assess which remediation strategies are most effective. Extensive pre- and post-remediation data for water and sediment quality for the Boulder River watershed in southwestern Montana provide an unusual opportunity to demonstrate the importance of monitoring. The most extensive restoration in the watershed occurred at the Comet mine on High Ore Creek and resulted in the most dramatic improvement in aquatic habitat. Removal of contaminated sediment and tailings, and stream-channel reconstruction reduced Cd and Zn concentrations in water such that fish are now present, and reduced metal concentrations in streambed sediment by a factor of c. 10, the largest improvement in the district. Waste removals at the Buckeye/Enterprise and Bullion mine sites produced limited or no improvement in water and sediment quality, and acidic drainage from mine adits continues to degrade stream aquatic habitat. Recontouring of hillslopes that had funnelled runoff into the workings of the Crystal mine substantially reduced metal concentrations in Uncle Sam Gulch, but did not eliminate all of the acidic adit drainage. Lead isotopic evidence suggests that the Crystal mine rather than the Comet mine is now the largest source of metals in streambed sediment of the Boulder River. The completed removal actions prevent additional contaminants from entering the stream, but it may take many years for erosional processes to diminish the effects of contaminated sediment already in streams. Although significant strides have been made, additional efforts to seal draining adits or treat the adit effluent at the Bullion and Crystal mines would need to be completed to

  14. Is soil dressing a way once and for all in remediation of arsenic contaminated soils? A case study of arsenic re-accumulation in soils remediated by soil dressing in Hunan Province, China.

    Science.gov (United States)

    Su, Shiming; Bai, Lingyu; Wei, Caibing; Gao, Xiang; Zhang, Tuo; Wang, Yanan; Li, Lianfang; Wang, Jinjin; Wu, Cuixia; Zeng, Xibai

    2015-07-01

    The investigation of arsenic (As) re-accumulation in an area previously remediated by soil dressing will help in sustainable controlling the risks of As to local ecosystems and should influence management decisions about remediation strategies. In this study, As content in an area remediated by soil dressing and the possible As accumulation risk in agricultural products were investigated. The results indicated that after 7 years of agricultural activities, the average As content (24.6 mg kg(-1)) in surface soil of the investigated area increased by 83.6% compared with that (13.4 mg kg(-1)) in clean soil. Of the surface soil samples (n = 88), 21.6% had As levels that exceeded the limits of the Environmental Quality Standard for Soils of China (GB 15618-1995) and 98.9% of the surface soil samples with As contents exceeding that in clean soil was observed. Soil dressing might be not a remediation method once and for all in some contaminated areas, even though no significant difference in available As content was found between clean (0.18 mg kg(-1)) and surface (0.22 mg kg(-1)) soils. The foreign As in surface soil of the investigated area mainly specifically sorbed with soil colloid or associated with hydrous oxides of Fe and Al, or existed in residual fraction. The upward movement of contaminated soil from the deeper layers and the atmospheric deposition of slag particles might be responsible for the re-accumulation of As in the investigated area. Decreases in soil pH in the investigated soils and the fact that no plant samples had As levels exceeding the limits of the National Food Safety Standards for Contaminants of China (GB 2762-2012) were also observed.

  15. Using slow-release permanganate candles to remediate PAH-contaminated water

    Energy Technology Data Exchange (ETDEWEB)

    Rauscher, Lindy, E-mail: purplerauscher@neb.rr.com [School of Natural Resources, University of Nebraska, Lincoln, NE 68583-0915 (United States); Sakulthaew, Chainarong, E-mail: chainarong@huskers.unl.edu [School of Natural Resources, University of Nebraska, Lincoln, NE 68583-0915 (United States); Department of Veterinary Technology, Kasetsart University, Bangkok 10900 (Thailand); Comfort, Steve, E-mail: scomfort1@unl.edu [School of Natural Resources, University of Nebraska, Lincoln, NE 68583-0915 (United States)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer We quantified the efficacy of slow-release permanganate-paraffin candles to degrade and mineralize PAHs. Black-Right-Pointing-Pointer {sup 14}C-labeled PAHs were used to quantify both adsorption and transformation. Black-Right-Pointing-Pointer Permanganate-treated PAHs were more biodegradable in soil microcosms. Black-Right-Pointing-Pointer A flow-through candle system was used to quantify PAH removal in urban runoff. - Abstract: Surface waters impacted by urban runoff in metropolitan areas are becoming increasingly contaminated with polycyclic aromatic hydrocarbons (PAHs). Slow-release oxidant candles (paraffin-KMnO{sub 4}) are a relatively new technology being used to treat contaminated groundwater and could potentially be used to treat urban runoff. Given that these candles only release permanganate when submerged, the ephemeral nature of runoff events would influence when the permanganate is released for treating PAHs. Our objective was to determine if slow-release permanganate candles could be used to degrade and mineralize PAHs. Batch experiments quantified PAH degradation rates in the presence of the oxidant candles. Results showed most of the 16 PAHs tested were degraded within 2-4 h. Using {sup 14}C-labled phenanthrene and benzo(a)pyrene, we demonstrated that the wax matrix of the candle initially adsorbs the PAH, but then releases the PAH back into solution as transformed, more water soluble products. While permanganate was unable to mineralize the PAHs (i.e., convert to CO{sub 2}), we found that the permanganate-treated PAHs were much more biodegradable in soil microcosms. To test the concept of using candles to treat PAHs in multiple runoff events, we used a flow-through system where urban runoff water was pumped over a miniature candle in repetitive wet-dry, 24-h cycles. Results showed that the candle was robust in removing PAHs by repeatedly releasing permanganate and degrading the PAHs. These results provide

  16. Characterization and Low-Cost Remediation of Soils Contaminated by Timbers in Community Gardens.

    Science.gov (United States)

    Heiger-Bernays, W; Fraser, A; Burns, V; Diskin, K; Pierotti, D; Merchant-Borna, K; McClean, M; Brabander, D; Hynes, H P

    2009-01-01

    Urban community gardens worldwide provide significant health benefits to those gardening and consuming fresh produce from them. Urban gardens are most often placed in locations and on land in which soil contaminants reflect past practices and often contain elevated levels of metals and organic contaminants. Garden plot dividers made from either railroad ties or chromated copper arsenate (CCA) pressure treated lumber contribute to the soil contamination and provide a continuous source of contaminants. Elevated levels of polycyclic aromatic hydrocarbons (PAHs) derived from railroad ties and arsenic from CCA pressure treated lumber are present in the gardens studied. Using a representative garden, we 1) determined the nature and extent of urban community garden soil contaminated with PAHs and arsenic by garden timbers; 2) designed a remediation plan, based on our sampling results, with our community partner guided by public health criteria, local regulation, affordability, and replicability; 3) determined the safety and advisability of adding city compost to Boston community gardens as a soil amendment; and 4) made recommendations for community gardeners regarding healthful gardening practices. This is the first study of its kind that looks at contaminants other than lead in urban garden soil and that evaluates the effect on select soil contaminants of adding city compost to community garden soil.

  17. Remediation of Ni2+-contaminated water using iron powder and steel manufacturing byproducts

    Institute of Scientific and Technical Information of China (English)

    JIN Jian; ZHAO Wei-rong; XU Xin-hua; HAO Zhi-wei; LIU Yong; HE Ping; ZHOU Mi

    2006-01-01

    Steel manufacturing byproducts and commercial iron powders were tested in the treatment of Ni2+-contaminated water. Ni2+is a priority pollutant of some soils and groundwater. The use of zero-valent iron, which can reduce Ni2+ to its neural form appears to be an alternative approach for the remediation of Ni2+-contaminated sites. Our experimental data show that the removal efficiencies of Ni2+ were 95.15% and 94.68% at a metal to solution ratio of 20 g/L for commercial iron powders and the steel manufacturing byproducts in 60 min at room temperature, respectively. The removal efficiency reached 98.20% when the metal to solution ratio was40 g/L for commercial iron powders. Furthermore, we found that the removal efficiency was also largely affected by other factors such as the pHs of the treated water, the length of time for the metal to be in contact with the Ni2+-contaminated water, initial concentrations of metal solutions, particle sizes and the amount of iron powders. Surprisingly, the reaction temperature appeared to have little effect on the removal efficiency. Our study opens the way to further optimize the reaction conditions of in situ remediation of Ni2+ or other heavy metals on contaminated sites.

  18. Remediation of nitrobenzene contaminated soil by combining surfactant enhanced soil washing and effluent oxidation with persulfate.

    Directory of Open Access Journals (Sweden)

    Jingchun Yan

    Full Text Available The combination of surfactant enhanced soil washing and degradation of nitrobenzene (NB in effluent with persulfate was investigated to remediate NB contaminated soil. Aqueous solution of sodium dodecylbenzenesulfonate (SDBS, 24.0 mmol L-1 was used at a given mass ratio of solution to soil (20:1 to extract NB contaminated soil (47.3 mg kg-1, resulting in NB desorption removal efficient of 76.8%. The washing effluent was treated in Fe2+/persulfate and Fe2+/H2O2 systems successively. The degradation removal of NB was 97.9%, being much higher than that of SDBS (51.6% with addition of 40.0 mmol L-1 Fe2+ and 40.0 mmol L-1 persulfate after 15 min reaction. The preferential degradation was related to the lone pair electron of generated SO4•-, which preferably removes electrons from aromatic parts of NB over long alkyl chains of SDBS through hydrogen abstraction reactions. No preferential degradation was observed in •OH based oxidation because of its hydrogen abstraction or addition mechanism. The sustained SDBS could be reused for washing the contaminated soil. The combination of the effective surfactant-enhanced washing and the preferential degradation of NB with Fe2+/persulfate provide a useful option to remediate NB contaminated soil.

  19. Olive oil mill wastewater for remediation of slag contaminated soil.

    Science.gov (United States)

    Ferrara, Luciano; Panzella, Lucia; Napolitano, Alessandra; Giudicianni, Italo; d'Ischia, Marco; Arienzo, Michele

    2013-12-01

    Two olive mill wastewaters (OMW) samples, OMWa and OMWb, containing different polyphenolic loads were used for decontaminating an unauthorized dump site in the Campania region, south Italy. In a bench-scale experiment, OMWa at pH 6.0 (OMWapH6.0) and 4.7 (OMWapH4.7), OMWb at pH 4.7 (OMWbpH4.7) and OMWa free of the polyphenolic moiety polyphenol-free OMWa (PF-OMWa) were added to the soil for a 96 h contact time. At 96 h, OMWapH4.7 was more effective than OMWapH6.0, with Cd, Cu, Pb and Zn removal percentages of 30.7-68.1. Cd and Pb levels were 6.0 and 915 mg kg(-1), respectively, decreasing below the regulatory limits for industrial and commercial areas (15.0 and 1 × 10(3) mg kg(-1), respectively). A threefold decrease in Zn levels was also observed from 13.5 × 10(3) to 4.3 × 10(3) mg kg(-1). The metal removal efficiency of PF-OMWa dropped from 30.7 % to 15.6 % for Cd and from 37.9 % to 1.3 % for Pb. OMWbpH4.7 at 96 h was more efficient than OMWapH4.7, with mean removal percentages of 32.5 versus 7.8, respectively.

  20. Development of Enhanced Remedial Techniques for Petroleum Fuel and Related Contaminants in Soil and Groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Paul Fallgren

    2009-02-10

    Western Research Institute (WRI) in conjunction with Earth Tech and the U.S. Department of Energy (DOE) was to identify proper sites with soils and/or groundwater contaminated by petroleum constituents and MTBE. Biodegradation rates would have been quantitatively assessed in both laboratory and field tests to achieve the optimal destruction of contaminants of concern. WRI and Earth Tech identified a site contaminated with high concentrations of methanol associated with petroleum hydrocarbons. The site was assessed and a remediation project plan was prepared; however, the site was soon acquired by a new company. An agreement between Earth Tech, WRI, and the new site owners could not be reached; therefore, a work was performed to identify a new project site. Task 33 was terminated and the available funding was redeployed to other Tasks after receiving approval from the U.S. DOE task manager.

  1. ACTIVE CAPPING TECHNOLOGY - NEW APPROACHES FOR IN SITU REMEDIATION OF CONTAMINATED SEDIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Knox, A.; Paller, M.; Roberts, J.

    2012-02-13

    This study evaluated pilot-scale active caps composed of apatite, organoclay, biopolymers, and sand for the remediation of metal-contaminated sediments. The active caps were constructed in Steel Creek, at the Savannah River Site near Aiken, South Carolina. Monitoring was conducted for 12 months. Effectiveness of the caps was based on an evaluation of contaminant bioavailability, resistance to erosion, and impacts on benthic organisms. Active caps lowered metal bioavailability in the sediment during the one-year test period. Biopolymers reduced sediment suspension during cap construction, increased the pool of carbon, and lowered the release of metals. This field validation showed that active caps can effectively treat contaminants by changing their speciation, and that caps can be constructed to include more than one type of amendment to achieve multiple goals.

  2. Review of remediation techniques for arsenic (As) contamination: a novel approach utilizing bio-organisms.

    Science.gov (United States)

    Rahman, Shahedur; Kim, Ki-Hyun; Saha, Subbroto Kumar; Swaraz, A M; Paul, Dipak Kumar

    2014-02-15

    Arsenic (As) contamination has recently become a worldwide problem, as it is found to be widespread not only in drinking water but also in various foodstuffs. Because of the high toxicity, As contamination poses a serious risk to human health and ecological system. To cope with this problem, a great deal of effort have been made to account for the mechanisms of As mineral formation and accumulation by some plants and aquatic organisms exposed to the high level of As. Hence, bio-remediation is now considered an effective and potent approach to breakdown As contamination. In this review, we provide up-to-date knowledge on how biological tools (such as plants for phytoremediation and to some extent microorganisms) can be used to help resolve the effects of As problems on the Earth's environment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Assessment of the Use of Natural Materials for the Remediation of Cadmium Soil Contamination

    Science.gov (United States)

    de O. Pinto, Tatiana; García, Andrés C.; Guedes, Jair do N.; do A. Sobrinho, Nelson M. B.; Tavares, Orlando C. H.

    2016-01-01

    Rice plants accumulate cadmium (Cd2+) within the grain, increasing the danger of human exposure. Natural materials have been used in soil remediation, but few studies have examined the risks (based on the bioavailability of these metals to plants) of using these materials, so the practice remains controversial. In the present study, we evaluated the effectiveness of biochar produced from sugarcane bagasse, vermicompost (VC), vermicompost solid residue (VCR) and humin for remediation of Cd2+-contaminated soils. We characterized the interactions between these materials and Cd2+ and evaluated their capacity to alter Cd2+ availability to rice plants. Our results show that under the conditions in this study, biochar and humin were not effective for soil remediation. Although biochar had high Cd2+ retention, it was associated with high Cd2+ bioavailability and increased Cd2+ accumulation in rice plants. VC and VCR had high Cd2+ retention capacity as well as low Cd2+ availability to plants. These characteristics were especially notable for VCR, which was most effective for soil remediation. The results of our study demonstrate that in the tested materials, the bioavailability of Cd2+ to plants is related to their structural characteristics, which in turn determine their retention of Cd2+. PMID:27341440

  4. Implications of Using Thermal Desorption to Remediate Contaminated Agricultural Soil: Physical Characteristics and Hydraulic Processes.

    Science.gov (United States)

    O'Brien, Peter L; DeSutter, Thomas M; Casey, Francis X M; Derby, Nathan E; Wick, Abbey F

    2016-07-01

    Given the recent increase in crude oil production in regions with predominantly agricultural economies, the determination of methods that remediate oil contamination and allow for the land to return to crop production is increasingly relevant. Ex situ thermal desorption (TD) is a technique used to remediate crude oil pollution that allows for reuse of treated soil, but the properties of that treated soil are unknown. The objectives of this research were to characterize TD-treated soil and to describe implications in using TD to remediate agricultural soil. Native, noncontaminated topsoil and subsoil adjacent to an active remediation site were separately subjected to TD treatment at 350°C. Soil physical characteristics and hydraulic processes associated with agricultural productivity were assessed in the TD-treated samples and compared with untreated samples. Soil organic carbon decreased more than 25% in both the TD-treated topsoil and the subsoil, and total aggregation decreased by 20% in the topsoil but was unaffected in the subsoil. The alteration in these physical characteristics explains a 400% increase in saturated hydraulic conductivity in treated samples as well as a decrease in water retention at both field capacity and permanent wilting point. The changes in soil properties identified in this study suggest that TD-treated soils may still be suitable for sustaining vegetation, although likely at a slightly diminished capacity when directly compared with untreated soils.

  5. Assessment of the Use of Natural Materials for the Remediation of Cadmium Soil Contamination.

    Directory of Open Access Journals (Sweden)

    Tatiana de O Pinto

    Full Text Available Rice plants accumulate cadmium (Cd2+ within the grain, increasing the danger of human exposure. Natural materials have been used in soil remediation, but few studies have examined the risks (based on the bioavailability of these metals to plants of using these materials, so the practice remains controversial. In the present study, we evaluated the effectiveness of biochar produced from sugarcane bagasse, vermicompost (VC, vermicompost solid residue (VCR and humin for remediation of Cd2+-contaminated soils. We characterized the interactions between these materials and Cd2+ and evaluated their capacity to alter Cd2+ availability to rice plants. Our results show that under the conditions in this study, biochar and humin were not effective for soil remediation. Although biochar had high Cd2+ retention, it was associated with high Cd2+ bioavailability and increased Cd2+ accumulation in rice plants. VC and VCR had high Cd2+ retention capacity as well as low Cd2+ availability to plants. These characteristics were especially notable for VCR, which was most effective for soil remediation. The results of our study demonstrate that in the tested materials, the bioavailability of Cd2+ to plants is related to their structural characteristics, which in turn determine their retention of Cd2+.

  6. Characterization of Polyethylene Oxide and Sodium Alginate for Oil Contaminated-Sand Remediation

    Directory of Open Access Journals (Sweden)

    Jongwon Jung

    2017-01-01

    Full Text Available Biopolymers have been employed in many soil applications, such as oil-contaminated soil remediation, due to their environmentally friendly characteristics. This study focused on changes in the wettability and viscosity of polyethylene oxide (PEO and sodium alginate (SA, according to the variation in concentration and their impact on oil-contaminated soil remediation using biopolymer-decane displacement tests. The contact angle and interfacial tension vary with concentration by adding biopolymer to water; however both parameters yield relatively constant values within the range of 2–10 g/L for the concentration of PEO and SA. In this study, their influence on fluid invasion patterns is insignificant compared to viscosity and flow rate. Viscosity increases with the concentration of PEO and SA, within the range of 0–10 g/L, which causes the biopolymer-decane displacement ratio to increase with concentration. Biopolymer-decane displacement increases with injected fluid velocity. At low flow rates, the effect of the biopolymer concentration on the displacement ratio is prominent. However the effect decreases with an increase in flow rate. Thus both biopolymer concentration and injection velocity should be considered to achieve the economic efficiency of soil remediation. The experimental results for the distribution of soils with different grain sizes indicate that the displacement ratio increases with the uniformity of the coefficient of soils.

  7. Potential of weed species applied to remediation of soils contaminated with heavy metals

    Institute of Scientific and Technical Information of China (English)

    WEI Shu-He; ZHOU Qi-Xing; WANG Xin; CAO Wei; REN Li-ping; SONG Yu-fang

    2004-01-01

    To screen out a series of ideal plants that can effectively remedy contaminated soils by heavy metals is the main groundwork of phytoremediation engineering and the first step of its commercial application on a large scale. In this study, accumulation and endurance of 45 weed species in 16 families from an agricultural site were in situ examined by using the pot-culture field experiment, and remediation potential of some weed species with high accumulation of heavy metals was assayed. The results showed that Solanum nigrum and Conyza canadensis can not only accumulate high concentration of Cd, but also strongly endure to single Cd and Cd-Pb-Cu-Zn combined pollution. Thus the 2 weed species can be regarded as good hyperaccumulators for the remediation of Cd-contaminated soils. Although there were high Cd-accumulation in Artemigia selengensis, Znula britannica, Artemigia selengensis and Cephalanoplos setosum, their biomass was adversely affected due to action of heavy metals in the soils. If the problem of low endurance to heavy metals can be solved by a reinforcer, the 4 weed species can be perhaps applied commercially.

  8. Evaluation of the assimilation of As by vegetables in contaminated soils submitted to a remediation process

    Science.gov (United States)

    Pérez-Sirvent, Carmen; Martinez Sanchez, Maria Jose; Agudo, Ines; Belen Martinez, Lucia; Bech, Jaume

    2016-04-01

    A greenhouse trial was carried out to evaluate the assimilation of heavy metals by three types of plants (lettuce, onion and broccoli), different parts of which are destined for human and farm animals consumption (leaves, roots, fruits). The experiments were carried out to check the validity of the use of calcareous materials to recover soils contaminated with heavy metals. The aim of this work was to apply a technology for decontamination to ensure that As do not enter into the trophic chain at risky levels and analyze and to assess the risk pre and post operational of the different treatments proposed. The materials used was a soils to be remediated (mining soils) and the materials used for remediation were lime filler and Construction and Demolition Waste (CDW). The plants were cultivated in greenhouse with several types of soil. Five experiments were used, namely, Tc (contaminated soil), T1 (uncontaminated soil (blank soil)), T2 (50% T1 + 50% Tc), T3 (Tc + (25%) lime residues coming from quarries) and T4 (Tc + (25%) residues coming from demolition and construction activities). The entire project involves twenty experiments which were prepared from soils highly contaminated mixed with two types of calcareous materials. The total As content of the soils samples, rhizosphere and vegetable samples, were measured and the translocation factor (TF), which is defined as the ratio of metal concentration in the leaves or shoots to the roots, and the Bioconcentration factor (BCF), which is defined as the ratio of metal concentration in the roots to that in soil were calculated. The use of CDR is shown to be a suitable way for remediating soils contaminated by metals. The methodology permits a revalorization of CDW.

  9. Subsurface Contaminant Focus Area: Monitored Natural Attenuation (MNA)--Programmatic, Technical, and Regulatory Issues

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, Kenneth M.; Martin, Wayne J.

    2001-07-23

    Natural attenuation processes are commonly used for remediation of contaminated sites. A variety of natural processes occur without human intervention at all sites to varying rates and degrees of effectiveness to attenuate (decrease) the mass, toxicity, mobility, volume, or concentration of organic and inorganic contaminants in soil, groundwater, and surface water systems. The objective of this review is to identify potential technical investments to be incorporated in the Subsurface Contaminant Focus Area Strategic Plan for monitored natural attenuation. When implemented, the technical investments will help evaluate and implement monitored natural attenuation as a remediation option at DOE sites. The outcome of this review is a set of conclusions and general recommendations regarding research needs, programmatic guidance, and stakeholder issues pertaining to monitored natural attenuation for the DOE complex.

  10. From conceptual model to remediation: bioavailability, a key to clean up heavy metal contaminated soils.

    Science.gov (United States)

    Petruzzelli, Gianniantonio; Pedron, Francesca; Pezzarossa, Beatrice

    2013-04-01

    Processes of metal bioavailability in the soil To know the bioavailability processes at site specific levels is essential to understand in detail the risks associated with pollution, and to support the decision-making process, i.e. description of the conceptual model and choice of clean up technologies. It is particularly important to assess how chemical, physical and biological processes in the soil affect the reactions leading to adsorption, precipitation or release of contaminants. The measurement of bioavailability One of the main difficulties in the practical application of the bioavailability concept in soil remediation is the lack of consensus on the method to be used to measure bioavailability. The best strategy is to apply a series of tests to assess bioavailability, since no applicable method is universally valid under all conditions. As an example, bioavailability tests for phytotechnology application should consider two distinct aspects: a physico-chemical driven solubilization process and a physiologically driven uptake process. Soil and plant characteristics strongly influence bioavailability. Bioavailability as a tool in remediation strategies Bioavailability can be used at all stages in remediation strategies: development of the conceptual model, evaluation of risk assessment, and selection of the best technology, considering different scenarios and including different environmental objectives. Two different strategies can be followed: the reduction and the increase of bioavailability. Procedures that reduce bioavailability aim to prevent the movement of pollutants from the soil to the living organisms, essentially by: i) removal of the labile phase of the contaminant, i.e. the fraction which is intrinsic to the processes of bioavailability (phytostabilization); ii) conversion of the labile fraction into a stable fraction (precipitation or adsorption); iii) increase of the resistance to mass transfer of the contaminants (inertization). Procedures

  11. Is there an environmental benefit from remediation of a contaminated site? Combined assessments of the risk reduction and life cycle impact of remediation

    DEFF Research Database (Denmark)

    Lemming, Gitte; Chambon, Julie Claire Claudia; Binning, Philip John;

    2012-01-01

    determined by a numerical risk assessment and remedial performance model, which predicted the contaminant mass discharge over time at a point of compliance in the aquifer and at the waterworks. The combined assessment of risk reduction and life cycle impacts showed that all management options result...

  12. Application of Microbial Products to Promote Electrodialytic Remediation of Heavy Metal Contaminated Soil

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland

    2006-01-01

    influences the remediation-time negatively. EDR remediation of fine grained, inorganic soils was documented to be feasible when the Pb is not associated with extremely stable compounds. The potential of treating other fine-grained materials in a suspended version of EDR had at this time been demonstrated...... of the lack of relevance to treatment of Pb-contaminated soil. Autotrophic leaching, which is leaching by acidophilic, autotrophic microorganisms obtaining energy by oxidation of elemental sulfur, was shown to induce acidification of soil-fines in suspension, but removal of Pb from the treated soil...... is optimal with distilled water as solvent. Consequently addition of nitric acid is recommended in cases where the removal rate is considered important, while suspension in pure water is recommended in situations where the energy expenditure and the chemical costs are limiting factors. Considering...

  13. REMEDIATION OF SOILS CONTAMINATED WITH MOTOR OIL BY HIGHLY BIODEGRADABLE SURFACTANTS

    Directory of Open Access Journals (Sweden)

    Ignacio Moya-Ramírez

    2014-06-01

    Full Text Available The remediation of a sandy soil contaminated with motor oil was studied by applying two different washing procedures: one discontinuous and the other continuous. In addition the capacity of three highly biodegradable surfactants, two synthetic (Glucopon 600 and Findet 1214N/23 and a biosurfactant from Bacillus subtilis, to enhance oil removal was tested. The results obtained with the continuous procedure were much better than those achieved with the discontinuous one, even in experiments conducted with distilled water. Both the addition of surfactants and the rise in temperature significantly increased the removal of the pollutant in experiments conducted with the discontinuous procedure, but the biosurfactant showed a higher capacity for soil remediation than the synthetic surfactants at concentrations close to its CMC. Conversely, when the continuous method was used, surfactant concentration seems to have a lower effect on motor oil removal, at least below the CMC.

  14. Feasibility study for remedial action for the groundwater operable units at the chemical plant area and the ordnance works area, Weldon Spring, Missouri

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-15

    The U.S. Department of Energy (DOE) and the U.S. Department of Army (DA) are conducting an evaluation to identify the appropriate response action to address groundwater contamination at the Weldon Spring Chemical Plant (WSCP) and the Weldon Spring Ordnance Works (WSOW), respectively. The two areas are located in St. Charles County, about 48 km (30 rni) west of St. Louis. The groundwater operable unit (GWOU) at the WSCP is one of four operable units being evaluated by DOE as part of the Weldon Spring Site Remedial Action Project (WSSRAP). The groundwater operable unit at the WSOW is being evaluated by the DA as Operable Unit 2 (OU2); soil and pipeline contamination are being managed under Operable Unit 1 (OU1). Remedial activities at the WSCP and the WSOW are being conducted in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Consistent with DOE policy, National Environmental Policy Act (NEPA) values have been incorporated into the CERCLA process. A remedial investigation/feasibility study (RI/FS) work plan summarizing initial site conditions and providing site hydrogeological and exposure models was published in August of 1995 (DOE 1995). The remedial investigation (RI) and baseline risk assessment (BRA) have also recently been completed. The RI (DOE and DA 1998b) discusses in detail the nature, extent, fate, and transport of groundwater and spring water contamination. The BRA (DOE and DA 1998a) is a combined baseline assessment of potential human health and ecological impacts and provides the estimated potential health risks and ecological impacts associated with groundwater and springwater contamination if no remedial action were taken. This feasibility study (FS) has been prepared to evaluate potential options for addressing groundwater contamination at the WSCP and the WSOW. A brief description of the history and environmental setting of the sites is presented in Section 1.1, key information relative to the

  15. STUDIES TO SUPPORT DEPLOYMENT OF EDIBLE OILS AS THE FINAL CVOC REMEDIATION IN T AREA SUMMARY REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Riha, B; Brian02 Looney, B; Miles Denham, M; Christopher Bagwell, C; Richard Hall, R; Carol Eddy-Dilek, C

    2006-10-31

    The purpose of these studies was to determine the feasibility of using edible oils for remediation of the low but persistent chlorinated solvent (cVOC) groundwater contamination at the SRS T-Area. The following studies were completed: (1) Review of cVOC degradation processes and edible oil delivery for enhanced bioremediation. (2) Column studies to investigate placing neat oil on top of the water table to increase oil saturation and sequestration. (3) Analysis of T-Area groundwater geochemistry to determine the applicability of edible oils for remediation at this site. (4) Microcosm studies to evaluate biotic and abiotic processes for the T-Area groundwater system and evaluation of the existing microbial community with and with out soybean oil amendments. (5) Monitoring of a surrogate vadose zone site undergoing edible oil remediation at the SRS to understand partitioning and biotransformation products of the soybean oil. (6) Design of a delivery system for neat and emulsified edible oil deployment for the T-Area groundwater plume. A corresponding white paper is available for each of the studies listed. This paper provides a summary and overview of the studies completed for the remediation of the T-Area groundwater plume using edible oils. This report begins with a summary of the results and a brief description of the preliminary oil deployment design followed by brief descriptions of T-Area and current groundwater conditions as related to edible oil deployment. This is followed by a review of the remediation processes using edible oils and specific results from modeling, field and laboratory studies. Finally, a description of the preliminary design for full scale oil deployment is presented.

  16. The effectiveness of electro-remediation of aged, metal-contaminated sediment in relation to sequential extraction of metals

    NARCIS (Netherlands)

    Merkx, O.K.; Loch, J.P.G.; Lima, A.T.; Dijk, J.A.; Kreuk, J.F. de; Kleingeld, P.J.

    2013-01-01

    Soil pollution is a universal environmental issue, and the clean-up of contaminated soils can be costly and time consuming. Traditional methods often do not provide an effective solution when it comes to fine-grained and highly impermeable soils and/or immobile contaminants. Electro-remediation, how

  17. Theory and application of landfarming to remediate polycyclic aromatic hydrocarbons and mineral oil-contaminated sediments: beneficial reuse

    NARCIS (Netherlands)

    Harmsen, J.; Rulkens, W.H.; Sims, R.C.; Rijtema, P.E.; Zweers, A.J.

    2007-01-01

    When applying landfarming for the remediation of contaminated soil and sediment, a fraction of the soil-bound contaminant is rapidly degraded; however, a residual concentration may remain, which slowly degrades. Degradation of polycyclic aromatic hydrocarbons (PAHs) and mineral oil can be described

  18. The effectiveness of electro-remediation of aged, metal-contaminated sediment in relation to sequential extraction of metals

    NARCIS (Netherlands)

    Merkx, O.K.; Loch, J.P.G.; Lima, A.T.; Dijk, J.A.; Kreuk, J.F. de; Kleingeld, P.J.

    2013-01-01

    Soil pollution is a universal environmental issue, and the clean-up of contaminated soils can be costly and time consuming. Traditional methods often do not provide an effective solution when it comes to fine-grained and highly impermeable soils and/or immobile contaminants. Electro-remediation, how

  19. Acoustic Cavitation: A Potential Remediation Technology for On-Site Elimination of Perfluorinated Contaminants

    Science.gov (United States)

    Vecitis, C. D.; Cheng, J.; Park, H.; Hoffmann, M. R.

    2006-12-01

    Perfluorinated chemicals are emerging as globally ubiquitous contaminants which are recalcitrant to the conventional remediation techniques of adsorption and chemical oxidation. The release of these chemicals to the environment occurs from specific sites such as manufacturing plants, fire-fighting foams at airports and contaminated landfills. Even though these compounds are widely recognized as potentially hazardous, disposal regulations have been limited due to the ineffectiveness of current pump and treat technologies towards these species. We have shown that ultrasonically induced acoustic cavitation can effectively mineralize aqueous perfluorinated acid and sulfonate species by in situ pyrolysis and chemical oxidation at the lab and pilot scale. Efficiency has been tested on a variety of matrices such as tap water, groundwater and landfill pump-out with VOC content being the major detriment towards remediation. Advanced oxidation by the simultaneously application of ozone and ultrasound seems to partially eliminate this barrier by enhancing the rate of VOC mineralization. Application of this technology to a contaminated field site and the obstacles of scaling to such a degree are discussed.

  20. Combined Effects of Biochar and Fertilizer on Cadmium Contaminated Soil Remediation

    Directory of Open Access Journals (Sweden)

    WANG Qi-kai

    2015-12-01

    Full Text Available The field experiment was employed to study on the combined effects of biochar and chicken manure and N, P and K compound chemical fertilizer on cadmium contaminated soil remediation, and the immobilization mechanism was elucidated through fractionation of cadmium in the tested soil. Results showed that the addition of these ammendments could significantly reduce the edible Cd accumulation in Lactuca sativa L., decreased from 32.6% to 54.8% compared with the control. The application of these additives could also significantly decrease extractable Cd concentration by 7.04%~21.85%. Biochar could significantly improve soil pH value, promote the inactivation of Cd contaminated soil, while the application of chicken manure significantly decreased soil pH value, which showed the effect of activating Cd in soil. Soil pH value had significant positive correlation with root Cd concentration of tested cultivars, but did not reach the significant effect level with the shoot Cd concentration. The research can provide a theoretical basis for the application of biochar combined with chicken manure and N, P and K compound chemical fertilizer on remediation of sewage irrigated Cd contaminated soil.

  1. Remediation of arsenic contaminated soil by coupling oxalate washing with subsequent ZVI/Air treatment.

    Science.gov (United States)

    Cao, Menghua; Ye, Yuanyao; Chen, Jing; Lu, Xiaohua

    2016-02-01

    The application of a novel coupled process with oxalate washing and subsequent zero-valent iron (ZVI)/Air treatment for remediation of arsenic contaminated soil was investigated in the present study. Oxalate is biodegradable and widely present in the environment. With addition of 0.1 mol L(-1) oxalate under circumneutral condition, 83.7% and 52.6% of arsenic could be removed from a spiked kaolin and an actual contaminated soil respectively. Much more oxalate adsorption on the actual soil was attributed to the higher soil organic matter and clay content. Interestingly, oxalate retained in the washing effluent could act as an organic ligand to promote the oxidation efficiency of ZVI/Air at near neutral pH. Compared with the absence of oxalate, much more As(III) was oxidized. Arsenic was effectively adsorbed on iron (hydr)oxides as the consumption of oxalate and the increase of pH value. For the actual soil washing effluent, about 94.9% of total arsenic was removed after 120 min's treatment without pH adjustment. It has been demonstrated that As(V) was the dominant arsenic speciation adsorbed on iron (hydr)oxides. This study provides a promising alternative for remediation of arsenic contaminated soil in view of its low cost and environmental benign.

  2. A review of biochars' potential role in the remediation, revegetation and restoration of contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Beesley, Luke, E-mail: luke.beesley@hutton.ac.uk [James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH (United Kingdom); Moreno-Jimenez, Eduardo [Departamento de Quimica Agricola, Universidad Autonoma de Madrid, 28049 Madrid (Spain); Gomez-Eyles, Jose L. [Department of Civil and Environmental Engineering, University of Maryland Baltimore County, Baltimore, MD 21250 (United States); Harris, Eva; Robinson, Brett [Department of Soil and Physical Sciences, Lincoln University, Lincoln 7647 (New Zealand); Sizmur, Tom [Soil Research Centre, Department of Geography and Environmental Science, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom)

    2011-12-15

    Biochars are biological residues combusted under low oxygen conditions, resulting in a porous, low density carbon rich material. Their large surface areas and cation exchange capacities, determined to a large extent by source materials and pyrolysis temperatures, enables enhanced sorption of both organic and inorganic contaminants to their surfaces, reducing pollutant mobility when amending contaminated soils. Liming effects or release of carbon into soil solution may increase arsenic mobility, whilst low capital but enhanced retention of plant nutrients can restrict revegetation on degraded soils amended only with biochars; the combination of composts, manures and other amendments with biochars could be their most effective deployment to soils requiring stabilisation by revegetation. Specific mechanisms of contaminant-biochar retention and release over time and the environmental impact of biochar amendments on soil organisms remain somewhat unclear but must be investigated to ensure that the management of environmental pollution coincides with ecological sustainability. - Highlights: > Biochars can reduce mobilities of some organic and inorganic pollutants in soil. > Source material and production conditions influence pollutant retention. > Highly alkaline pH and water soluble carbon can undesirably mobilise some elements. > Large surface area may be toxic to soil fauna but create microbial niches. > Efficacy of biochar may depend on other organic materials applied in combination. - Biochars can reduce the mobility and impact of some soil pollutants but, if applied alone, may fail to support soil restoration, revegetation and hence ecologically circumspect remediation.

  3. [Recent advance in solidification/stabilization technology for the remediation of heavy metals-contaminated soil].

    Science.gov (United States)

    Hao, Han-zhou; Chen, Tong-bin; Jin, Meng-gui; Lei, Mei; Liu, Cheng-wu; Zu, Wen-pu; Huang, Li-mi

    2011-03-01

    Remediation of heavy metals-contaminated soil is still a difficulty and a hotspot of international research projects. At present, the technologies commonly adopted for the remediation of contaminated sites mainly include excavation, solidification/stabilization (S/S), soil washing, soil vapor extraction (SVE), thermal treatment, and bioremediation. Based on the S/S technical guidelines of Unite State Environmental Protection Agency (EPA) and United Kingdom Environment Agency (EA) and the domestic and foreign patents, this paper introduced the concepts of S/S and its development status at home and abroad, and discussed its future development directions. Solidification refers to a process that binds contaminated media with a reagent, changing the media's physical properties via increasing its compressive strength, decreasing its permeability, and encapsulating the contaminants to form a solid material. Stabilization refers to the process that involves a chemical reaction which reduces the leachability of a waste, chemically immobilizes the waste and reduces its solubility, making the waste become less harmful or less mobile. S/S technology includes cement solidification, lime pozzolanic solidification, plastic materials stabilization, vitrification, and regent-based stabilization. Stabilization (or immobilization) treatment processes convert contaminants to less mobile forms through chemical or thermal interactions. In stabilization technology, the aim of adding agents is to change the soil physical and chemical properties through pH control technology, redox potential technology, precipitation techniques, adsorption technology, and ion-exchange technology that change the existing forms of heavy metals in soil, and thus, reduce the heavy metals bioavailability and mobility. This review also discussed the S/S evaluation methods, highlighted the need to enhance S/S technology in the molecular bonding, soil polymers, and formulation of China's S/S technical guidelines.

  4. INNOVATIVE IN-SITU REMEDIATION OF CONTAMINATED SEDIMENTS FOR SIMULTANEOUS CONTROL OF CONTAMINATION AND EROSION

    Energy Technology Data Exchange (ETDEWEB)

    Knox, A; Michael Paller, M; Danny D. Reible, D; Ioana G. Petrisor, I

    2007-11-28

    New technologies are needed that neutralize contaminant toxicity and control physical transport mechanisms that mobilize sediment contaminants. The last 12 months of this comprehensive project investigated the use of combinations of sequestering agents to develop in situ active sediment caps that stabilize mixtures of contaminants and act as a barrier to mechanical disturbance under a broad range of environmental conditions. Efforts focused on the selection of effective sequestering agents for use in active caps, the composition of active caps, and the effects of active cap components on contaminant bioavailability and retention. Results from this project showed that phosphate amendments, some organoclays, and the biopolymer, chitosan, were very effective at removing metals from both fresh and salt water. These amendments also exhibited high retention (80% or more) of most metals indicating reduced potential for remobilization to the water column. Experiments on metal speciation and retention in contaminated sediment showed that apatite and organoclay can immobilize a broad range of metals under both reduced and oxidized conditions. These studies were followed by sequential extractions to evaluate the bioavailability and retention of metals in treated sediments. Metal fractions recovered in early extraction steps are more likely to be bioavailable and were termed the Potentially Mobile Fraction (PMF). Less bioavailable fractions collected in later extraction steps were termed the Recalcitrant Factor (RF). Apatite and organoclay reduced the PMF and increased the RF for several elements, especially Pb, Zn, Ni, Cr, and Cd. Empirically determined partitioning coefficients and modeling studies were used to assess the retention of organic contaminants on selected sequestering agents. Organoclays exhibited exceptionally high sorption of polycyclic aromatic hydrocarbons as indicated by a comparison of K{sub d} values among 12 amendments. These results suggested that

  5. Use of plant and earthworm bioassays to evaluate remediation of soil from a site contaminated with polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Meier, J.R.; Chang, L.W.; Meckes, M.C.; Smith, M.K. [Environmental Protection Agency, Cincinnati, OH (United States); Jacobs, S. [DynCorp, Cincinnati, OH (United States); Torsella, J. [Oak Ridge Inst. of Science and Education, Cincinnati, OH (United States)

    1997-05-01

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction technology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The earthworm toxicity bioassays were the 14-d survival test and 21-d reproduction test, using Lumbricus terrestris and Eisenia fetida andrei. The plant bioassays included phytotoxicity tests for seed germination and root elongation in lettuce and oats, and a genotoxicity test (anaphase aberrations) in Allium cepa (common onion). Although the PCB content of the soil was reduced by 99% (below the remediation goal), toxicity to earthworm reproduction remained essentially unchanged following remediation. Furthermore, phytotoxicity and genotoxicity were higher for the remediated soil compared to the untreated soil. The toxicity remaining after treatment appeared to be due to residual solvent introduced during the remediation process, and/or to heavy metals or other inorganic contaminants not removed by the treatment. Mixture studies involving isopropanol and known toxicants indicated possible synergistic effects of the extraction solvent and soil contaminants. The toxicity in plants was essentially eliminated by a postremediation, water-rinsing step. These results demonstrate a need for including toxicity measurements in the evaluation of technologies used in hazardous waste site remediations, and illustrate the potential value of such measurements for making modifications to remediation processes.

  6. [Leaching Remediation of Copper and Lead Contaminated Lou Soil by Saponin Under Different Conditions].

    Science.gov (United States)

    Deng, Hong-xia; Yang, Ya-li; Li, Zhen; Xu, Yan; Li, Rong-hua; Meng, Zhao-fu; Yang, Ya-ti

    2015-04-01

    In order to investigate the leaching remediation effect of the eco-friendly biosurfactant saponin for Cu and Pb in contaminated Lou soil, batch tests method was used to study the leaching effect of saponin solution on single Cu, Pb contaminated Lou soil and mixed Cu and Pb contaminated Lou soil under different conditions such as reaction time, mass concentration of saponin, pH, concentration of background electrolyte and leaching times. The results showed that the maximum leaching removal effect of Cu and Pb in contaminated Lou soil was achieved by complexation of the heavy metals with saponin micelle, when the mass concentration of saponin solution was 50 g x L(-1), pH was 5.0, the reaction time was 240 min, and there was no background electrolyte. In single and mixed contaminated Lou soil, the leaching percentages of Cu were 29.02% and 25.09% after a single leaching with 50 g x L(-1) saponin under optimal condition, while the single leaching percentages of Pb were 31.56% and 28.03%, respectively. The result indicated the removal efficiency of Pb was more significant than that of Cu. After 4 times of leaching, the cumulative leaching percentages of Cu reached 58.92% and 53.11%, while the cumulative leaching percentages of Pb reached 77.69% and 65.32% for single and mixed contaminated Lou soil, respectively. The fractionation results of heavy metals in soil before and after a single leaching showed that the contents of adsorbed and exchangeable Cu and Pb increased in the contaminated soil, while the carbonate-bound, organic bound and sulfide residual Cu and Pb in the contaminated Lou soil could be effectively removed by saponin.

  7. Modeling Adsorption Kinetics (Bio-remediation of Heavy Metal Contaminated Water)

    Science.gov (United States)

    McCarthy, Chris

    My talk will focus on modeling the kinetics of the adsorption and filtering process using differential equations, stochastic methods, and recursive functions. The models have been developed in support of our interdisciplinary lab group which is conducting research into bio-remediation of heavy metal contaminated water via filtration through biomass such as spent tea leaves. The spent tea leaves are available in large quantities as a result of the industrial production of tea beverages. The heavy metals bond with the surfaces of the tea leaves (adsorption). Funding: CUNY Collaborative Incentive Research Grant.

  8. Remediation of contaminated areas. An overview of international guidance

    DEFF Research Database (Denmark)

    Jensen, Per Hedemann

    1999-01-01

    restoration techniques -assessment of the radiological impact -development and application of a selection methodology for restoration options -formulation ofgeneric conclusions and development of a manual The project is intended to apply to situations in which sites with nuclear installations have been...... against chronic exposure are being developed byAdvisory Groups and Task Groups within the International Atomic Energy Agency (IAEA) and the International Commission on Radiological Protection (ICRP). This work has been reviewed and a status as of the beginning of 1998 is given. For illustrativepurposes...

  9. Mathematical Model of In-situ Ozonation for the Remediation of 2-Chlorophenol Contaminated Soil

    Institute of Scientific and Technical Information of China (English)

    张晖; 宋孟浩; 黄金宝

    2003-01-01

    A microscopic diffusion-reaction model was developed to simulate in-situ ozonation for the remediation of contaminated soil, i.e., to predict the temporal and spatial distribution of target contaminant in the subsurface.The sequential strategy was employed to obtain the numerical solution of the model using finite difference method. A non-uniform grid of discretization points was employed to increase the accuracy of the numerical solution by means of coordinate transformation. One-dimensional column tests were conducted to verify the model. The column was packed with simulated soils that were spiked with 2-chlorophenol. Ozone gas passed through the column at a flow rate of 100 ml·min-1. The residual 2-chlorophenol content at different depths of the column was determined at fixed time intervals. Compared the experimental data with the simulated values, it was found that the mathematical model fitted data well during most time of the experiment.

  10. Validation of microplate bioassays for the assessment of contaminated and remediated sites. Laboratory-intercomparison study

    Energy Technology Data Exchange (ETDEWEB)

    Rila, J.P. [National Inst. for Public Health and the Environment, Bilthoven (Netherlands); Hund-Rinke, K. [Fraunhofer Inst. for Molecular Biology and Applied Ecology, Schmallenberg (Germany); Pfeifer, F. [Deutsche Montan Technologie GmbH, Essen (Germany); Dott, W.; Eisentraeger, A. [Inst. of Hygiene and Environmental Medicine, Aachen (Germany)

    2003-07-01

    The toxicological assessment of the contaminated and remediated soil samples using LID-values, as a rule, was highly uniform. Some minor deviations could, for the most part, be explained by the heterogeneity of the soil samples and, to a lesser extent, by methodical aspects. The difference in sensitivity towards contaminants of the two bacteria Vibrio fischeri and Pseudomonas putida was pointed out. In the algae test with Desmodesmus subspicatus, the influence of the highest sample concentrations on the growth controls became obvious. It was recommended to modify the experimental setup of the microtitration plate, i.e. to place growth controls located next to both the lowest and the highest dilution steps of the sample. The Ames-test did in some cases provide new information on the genotoxicity of the samples, but is not considered useful in a test battery for the evaluation of the genotoxic potential because of its great expense in time and work. (orig.)

  11. (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.

  12. Electrochemical remediation of copper contaminated kaolinite by conditioning anolyte and catholyte pH simultaneously

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This report examined electrochemical remediation of copper contaminated kaolinite by controlling electrolytes' pH for both of anolyte and catholyte simultaneously. Results showed that electrokinetic process and remediation efficiency varied obviously when different buffer systems, including citric acid (test 1), nitric acid + EDTA (test 2) and nitric acid (test 3), were used to control catholyte pH and Na2CO3 was used at the same time to control all anolyte one. It was found that under such pH condition soil's pH in soil column kept at 3.0-7.0 successfully, and correspondingly no copper precipitation and decrease of soil electroconductivity appeared, which are usually observed in electrokinetic process due to OH- introduction into soil column by electrochemical reaction occurred in cathode. Electroosmosis flow rates were almost equal for these three tests, indicating that these buffers did not affect Zeta-potential of kaolinite within the examined duration. More acid and basic solution was added into electrokinetic cell when nitric acid was used as buffer than when nitric acid + EDTA and then citric acid were used. Due to introduction of large amounts of ions into soil column, significant higher current was observed for test 3 than other two. Analysis of copper speciation and total quantity in kaolinite indicated that 55.65%, 22.5% and 23.74% Cu were removed from kaolinite for test 1, test 2 and test 3 respectively after only 10 days' electrokinetic remediation.

  13. Is there an environmental benefit from remediation of a contaminated site? Combined assessments of the risk reduction and life cycle impact of remediation.

    Science.gov (United States)

    Lemming, Gitte; Chambon, Julie C; Binning, Philip J; Bjerg, Poul L

    2012-12-15

    A comparative life cycle assessment is presented for four different management options for a trichloroethene-contaminated site with a contaminant source zone located in a fractured clay till. The compared options are (i) long-term monitoring (ii) in-situ enhanced reductive dechlorination (ERD), (iii) in-situ chemical oxidation (ISCO) with permanganate and (iv) long-term monitoring combined with treatment by activated carbon at the nearby waterworks. The life cycle assessment included evaluation of both primary and secondary environmental impacts. The primary impacts are the local human toxic impacts due to contaminant leaching into groundwater that is used for drinking water, whereas the secondary environmental impacts are related to remediation activities such as monitoring, drilling and construction of wells and use of remedial amendments. The primary impacts for the compared scenarios were determined by a numerical risk assessment and remedial performance model, which predicted the contaminant mass discharge over time at a point of compliance in the aquifer and at the waterworks. The combined assessment of risk reduction and life cycle impacts showed that all management options result in higher environmental impacts than they remediate, in terms of person equivalents and assuming equal weighting of all impacts. The ERD and long-term monitoring were the scenarios with the lowest secondary life cycle impacts and are therefore the preferred alternatives. However, if activated carbon treatment at the waterworks is required in the long-term monitoring scenario, then it becomes unfavorable because of large secondary impacts. ERD is favorable due to its low secondary impacts, but only if leaching of vinyl chloride to the groundwater aquifer can be avoided. Remediation with ISCO caused the highest secondary impacts and cannot be recommended for the site. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Remediation of soils contaminated with particulate depleted uranium by multi stage chemical extraction

    Energy Technology Data Exchange (ETDEWEB)

    Crean, Daniel E. [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield (United Kingdom); Centre for Radiochemistry Research, School of Chemistry, The University of Manchester (United Kingdom); Livens, Francis R.; Sajih, Mustafa [Centre for Radiochemistry Research, School of Chemistry, The University of Manchester (United Kingdom); Stennett, Martin C. [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield (United Kingdom); Grolimund, Daniel; Borca, Camelia N. [Swiss Light Source, Paul Scherrer Institute, Villigen (Switzerland); Hyatt, Neil C., E-mail: n.c.hyatt@sheffield.ac.uk [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield (United Kingdom)

    2013-12-15

    Highlights: • Batch leaching was examined to remediate soils contaminated with munitions depleted uranium. • Site specific maximum extraction was 42–50% total U in single batch with NH{sub 4}HCO{sub 3}. • Analysis of residues revealed partial leaching and secondary carbonate phases. • Sequential batch leaching alternating between NH{sub 4}HCO{sub 3} and citric acid was designed. • Site specific extraction was increased to 68–87% total U in three batch steps. -- Abstract: Contamination of soils with depleted uranium (DU) from munitions firing occurs in conflict zones and at test firing sites. This study reports the development of a chemical extraction methodology for remediation of soils contaminated with particulate DU. Uranium phases in soils from two sites at a UK firing range, MOD Eskmeals, were characterised by electron microscopy and sequential extraction. Uranium rich particles with characteristic spherical morphologies were observed in soils, consistent with other instances of DU munitions contamination. Batch extraction efficiencies for aqueous ammonium bicarbonate (42–50% total DU extracted), citric acid (30–42% total DU) and sulphuric acid (13–19% total DU) were evaluated. Characterisation of residues from bicarbonate-treated soils by synchrotron microfocus X-ray diffraction and X-ray absorption spectroscopy revealed partially leached U(IV)-oxide particles and some secondary uranyl-carbonate phases. Based on these data, a multi-stage extraction scheme was developed utilising leaching in ammonium bicarbonate followed by citric acid to dissolve secondary carbonate species. Site specific U extraction was improved to 68–87% total U by the application of this methodology, potentially providing a route to efficient DU decontamination using low cost, environmentally compatible reagents.

  15. Characterizing the Transport of a Novel, Engineered Nanoparticle for Use in Remediation of Hydrophobic Contaminants

    Science.gov (United States)

    Sanders, J. E.; Miller, G. R.

    2015-12-01

    Magnetic shell crosslinked knedel-like nanoparticles (MSCKs) were originally engineered to aid in the cleanup of oil spills. These polymeric particles are spherical and approximately 70 nm in diameter. MSCKs have a hydrophobic shell and hydrophilic core which encapsulates suspended iron oxide nanoparticles, rendering them magnetic. MSCKs operate like discrete surfactant packets: increasing the mobility and apparent solubility of hydrophobic species, but do so within the confines of discrete particles which can then be recovered by filtration or magnetic removal. MSCKs accomplish this via sequestration of hydrophobic species from through the hydrophilic shell and into the hydrophobic core where hydrocarbon contaminants are entropically stabilized. In batch reactor testing, MSCKs have been shown to sequester crude oil up to ten times their mass (1000 mg of oil per 100 mg of MSCKs). This study examines the transport characteristics and contaminant sequestration capabilities of MSCKs in saturated porous media, in order to establish their potential for use in groundwater remediation. Baseline MSCK transport parameters were determined via one dimensional impulse column experiments. MSCKs were readily transported in saturated sand, with an average recovery rate of 99%. In the presence of 10% clay particles, recovery was reduced to 68%. MSCKs were able to completely sequester an aqueous phase pollutant (8.7 mg/L m-xylene), although it further reduced their recovery rate to 61% in sand and 53% in clay. The presence of a free phase contaminant (5% of pore space occupied by mineral oil) reduced MSCKs recovery in sand to 53%. The MSCKs recovered in the effluent had sequestered the mineral at ratios far below their capability (3-10 mg of oil per 100 mg of MSCKs). Overall, this study indicated that MSCKs show a number of promising attributes for use in remediation. However, further manipulation of their chemical and morphological properties is needed, with the objective of

  16. Screening of contaminants in Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, B.G.; Frank, M.L.; Hoffman, F.O.; Hook, L.A.; Suter, G.W.; Watts, J.A.

    1992-07-01

    Waste Area Grouping 2 (WAG 2) of the Oak Ridge National Laboratory (ORNL) is located in the White Oak Creek Watershed and is composed of White Oak Creek Embayment, White Oak Lake and associated floodplain, and portions of White Oak Creek (WOC) and Melton Branch downstream of ORNL facilities. Contaminants leaving other ORNL WAGs in the WOC watershed pass through WAG 2 before entering the Clinch River. Health and ecological risk screening analyses were conducted on contaminants in WAG 2 to determine which contaminants were of concern and would require immediate consideration for remedial action and which contaminants could be assigned a low priority or further study. For screening purposes, WAG 2 was divided into four geographic reaches: Reach 1, a portion of WOC; Reach 2, Melton Branch; Reach 3, White Oak Lake and the floodplain area to the weirs on WOC and Melton Branch; and Reach 4, the White Oak Creek Embayment, for which an independent screening analysis has been completed. Screening analyses were conducted using data bases compiled from existing data on carcinogenic and noncarcinogenic contaminants, which included organics, inorganics, and radionuclides. Contaminants for which at least one ample had a concentration above the level of detection were placed in a detectable contaminants data base. Those contaminants for which all samples were below the level of detection were placed in a nondetectable contaminants data base.

  17. Assessment of Canadian Regulations and Remediation Methods for Diesel Oil Contaminated Soils

    Directory of Open Access Journals (Sweden)

    D. G. Rushton

    2007-01-01

    Full Text Available Diesel fuel released into the environment can contaminate ground water, degrade potable water supplies and cause the collapse of fisheries. They are toxic to both animals and humans and can affect the liver, lungs, kidneys, and nervous system leading to cancer as well as immunological and reproductive effects. The objectives of this study were to review current Canadian regulations pertaining to diesel fuel and to evaluate the current remediation methods using five criteria: efficiency, applicability, cost, time and cleanliness. PAHs are deemed toxic under the Canadian Environmental Protection Act but no standards have been set for PAHs in diesel. The Canadian Council of Ministers of the Environment (CCME has developed Canada-Wide Standards for Petroleum Hydrocarbons in Soil (CWS PHCS while the Atlantic PIRI has implemented a Risk Based Corrective Action (RBCA for the Atlantic region. The remediation methods included soil washing, landfilling, incineration, thermal desorption, radio frequency heating, chemical addition, landfarming, biopiling, composting, bioventing, liquid delivery and bioreactors. The bioreactors studied included: static bed, continuous mix, horizontal drum, fungal compost, slurry-phase, DITS, biofilters and packed bed bioreactors. The results showed that the biological methods were more effective than nonbiological ones and the bioreactors scored the highest among the biological methods. Eight criteria were then used for the evaluation of bioreactors: efficiency, time, cost, maintenance, simplicity, release of VOCs to the atmosphere, containment of contaminants and control of operating parameters The results showed that the continuous mix bioreactor was the most effective system.

  18. Rhizobia and their bio-partners as novel drivers for functional remediation in contaminated soils

    Science.gov (United States)

    Teng, Ying; Wang, Xiaomi; Li, Lina; Li, Zhengao; Luo, Yongming

    2015-01-01

    Environmental pollutants have received considerable attention due to their serious effects on human health. There are physical, chemical, and biological means to remediate pollution; among them, bioremediation has become increasingly popular. The nitrogen-fixing rhizobia are widely distributed in the soil and root ecosystems and can increase legume growth and production by supplying nitrogen, resulting in the reduced need for fertilizer applications. Rhizobia also possess the biochemical and ecological capacity to degrade organic pollutants and are resistant to heavy metals, making them useful for rehabilitating contaminated soils. Moreover, rhizobia stimulate the survival and action of other biodegrading bacteria, thereby lowering the concentration of pollutants. The synergistic action of multiple rhizobial strains enhances both plant growth and the availability of pollutants ranging from heavy metals to persistent organic pollutants. Because phytoremediation has some restrictions, the beneficial interaction between plants and rhizobia provides a promising option for remediation. This review describes recent advances in the exploitation of rhizobia for the rehabilitation of contaminated soil and the biochemical and molecular mechanisms involved, thereby promoting further development of this novel bioremediation strategy into a widely accepted technique. PMID:25699064

  19. Remediation of Biological Organic Fertilizer and Biochar in Paddy Soil Contaminated by Cd and Pb

    Directory of Open Access Journals (Sweden)

    MA Tie-zheng

    2015-02-01

    Full Text Available The effect of application of biological organic fertilizer and biochar on the immobilized remediation of paddy soil contaminated by Cd and Pb was studied under the field experiment. The results showed that biological organic fertilizer and biochar increased the soil pH and soil nutrient contents, and reduced the soil available Cd and Pb concentrations significantly. The soil pH had significantly negative correla-tion with the soil available Cd and Pb contents. The application of biological organic fertilizer and biochar decreased Cd and Pb concentration in all parts of the rice plant, with Cd concentration in brown rice decrease by 22.00% and 18.34% and Pb decease in brown rice by 33.46% and 12.31%. The concentration of Cd and Pb in brown rice had significant positive correlation with the soil available Cd and Pb concentra-tions. It was observed that both biological organic fertilizer and biochar had a positive effect on the remediation of paddy soil contaminated by Cd and Pb.

  20. Rhizobia and their bio-partners as novel drivers for functional remediation in contaminated soils.

    Science.gov (United States)

    Teng, Ying; Wang, Xiaomi; Li, Lina; Li, Zhengao; Luo, Yongming

    2015-01-01

    Environmental pollutants have received considerable attention due to their serious effects on human health. There are physical, chemical, and biological means to remediate pollution; among them, bioremediation has become increasingly popular. The nitrogen-fixing rhizobia are widely distributed in the soil and root ecosystems and can increase legume growth and production by supplying nitrogen, resulting in the reduced need for fertilizer applications. Rhizobia also possess the biochemical and ecological capacity to degrade organic pollutants and are resistant to heavy metals, making them useful for rehabilitating contaminated soils. Moreover, rhizobia stimulate the survival and action of other biodegrading bacteria, thereby lowering the concentration of pollutants. The synergistic action of multiple rhizobial strains enhances both plant growth and the availability of pollutants ranging from heavy metals to persistent organic pollutants. Because phytoremediation has some restrictions, the beneficial interaction between plants and rhizobia provides a promising option for remediation. This review describes recent advances in the exploitation of rhizobia for the rehabilitation of contaminated soil and the biochemical and molecular mechanisms involved, thereby promoting further development of this novel bioremediation strategy into a widely accepted technique.

  1. Rhizobia and their bio-partners as novel drivers for functional remediation in contaminated soils

    Directory of Open Access Journals (Sweden)

    Ying eTeng

    2015-02-01

    Full Text Available Environmental pollutants have received considerable attention due to their serious effects on human health. There are physical, chemical, and biological means to remediate pollution; among them, bioremediation has become increasingly popular. The nitrogen-fixing rhizobia are widely distributed in the soil and root ecosystems and can increase legume growth and production by supplying nitrogen, resulting in the reduced need for fertilizer applications. Rhizobia also possess the biochemical and ecological capacity to degrade organic pollutants and are resistant to heavy metals, making them useful for rehabilitating contaminated soils. Moreover, rhizobia stimulate the survival and action of other biodegrading bacteria, thereby lowering the concentration of pollutants. The synergistic action of multiple rhizobial strains enhances both plant growth and the availability of pollutants ranging from heavy metals to persistent organic pollutants. Because phytoremediation has some restrictions, the beneficial interaction between plants and rhizobia provides a promising option for remediation. This review describes recent advances in the exploitation of rhizobia for the rehabilitation of contaminated soil and the biochemical and molecular mechanisms involved, thereby promoting further development of this novel bioremediation strategy into a widely accepted technique.

  2. Accumulation of Hydrocarbons by Maize (Zea mays L.) in Remediation of Soils Contaminated with Crude Oil.

    Science.gov (United States)

    Liao, Changjun; Xu, Wending; Lu, Guining; Liang, Xujun; Guo, Chuling; Yang, Chen; Dang, Zhi

    2015-01-01

    This study has investigated the use of screened maize for remediation of soil contaminated with crude oil. Pots experiment was carried out for 60 days by transplanting maize seedlings into spiked soils. The results showed that certain amount of crude oil in soil (≤2 147 mg·kg(-1)) could enhance the production of shoot biomass of maize. Higher concentration (6 373 mg·kg(-1)) did not significantly inhibit the growth of plant maize (including shoot and root). Analysis of plant shoot by GC-MS showed that low molecular weight polycyclic aromatic hydrocarbons (PAHs) were detected in maize tissues, but PAHs concentration in the plant did not increase with higher concentration of crude oil in soil. The reduction of total petroleum hydrocarbon in planted soil was up to 52.21-72.84%, while that of the corresponding controls was only 25.85-34.22% in two months. In addition, data from physiological and biochemical indexes demonstrated a favorable adaptability of maize to crude oil pollution stress. This study suggested that the use of maize (Zea mays L.) was a good choice for remediation of soil contaminated with petroleum within a certain range of concentrations.

  3. Using humic acid for remediation of sandy soils contaminated by heavy metal

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    This paper presents the development of a new remediation technology for contaminated sandy soil using humic acid (HA). Distribution of amount of Cr (VI) in the aqueous or solid system containing humic acid and sandy soil, was studied using batch experiments, es-pecially for effects of reaction time, pH, concentrations, temperature and irradiation on the reduction of Cr (VI), and the optimum reaction conditions. The results indicated a significant increase of the adsorption of Cr (VI) because of the complexion reaction between HA and Cr (VI) that occurred under acidic condition. The reaction mechanisms of HA with chromium on sand surfaces were certified. Thus it came to a conclusion that HA could be used effectively on remediation of Cr (VI)-contaminated soil and groundwater in a wide range of pH, with or without sunlight. These results suggest that the organic-inorganic complex-such as sandy soils coated with humic substances-is important as a metal reservoir in the environment.

  4. Limestone-based technosols: a suitable way for the remediation of sediments contaminated by heavy metals.

    Science.gov (United States)

    Martínez-Sanchez, Maria Jose; Garcia-Lorenzo, Mari Luz; Martínez, Salvadora; Gonzalez, Eva; Molina, Jose; Hernández, Carmen; Pérez-Sirvent, Carmen

    2013-04-01

    The aim of this work was to assess the suitability of limestone-based technosols for decreasing the toxicity of the leachates caused by rain in sites contaminated by heavy metals. For such a purpose, 64 technosols were prepared in containers of 0.75m3, filled with 4 types of sediments collected from Portman Bay and subjected to different stabilizer proportions (limestone filler), different thickness of a drainage layer and presence/absence of a topsoil cover. The technosols were then submitted to different humidity/dryness cycles simulating the usual rain conditions in the zone. Portman bay is situated close to the mining region of La Unión. The entire area around the bay was subject to mining from the time of the Roman Empire to 1991. Since 1957, the wastes from mining operations were discharged directly into the sea in the inner part of the bay, while later on, they were also discharged to sea at a distance of the shore. These wastes mainly consisted in ore materials (galena, pyrite and sphalerite), phyllosilicates, in addition to siderite, iron oxides and sometimes alteration products such as jarosite, alunite, kaolinite and greenalite. These materials have suffered a concentration process by floatation with sea water and as a result of the discharge, the whole of the bay has filled up with wastes which also extend into the Mediterranean Sea. The pH and the electrical conductivity (EC) was determined in obtained percolates, together with major ion content, determined by ionic chromatography. The Zn, Pb, Cd and Cu content was determined by electrothermal atomization atomic absorption spectrometry (ETAAS). The As content was measured by atomic fluorescence spectrometry. In addition, the mineralogical composition was determined in the evaporated samples by X-Ray diffraction. A battery of bioassays was applied for the ecotoxicological screening of obtained percolates . Particularly, the toxicity was evaluated by using three assays: microtox bioassay (Vibrio

  5. Remediation of petroleum contaminated soils by joint action of Pharbitis nil L. and its microbial community.

    Science.gov (United States)

    Zhang, Zhineng; Zhou, Qixing; Peng, Shengwei; Cai, Zhang

    2010-10-15

    The plot-culture experiments were conducted for examining the feasibility of Pharbitis nil L. and its microbial community to remedy petroleum contaminated soils. The petroleum contaminated soil, containing 10% (w/w) of the total petroleum hydrocarbons (TPHs), was collected from the Shengli Oil Field, Dongying City, Shandong Province, China. The collected soil was applied and diluted to a series of petroleum contaminated soils (0.5%, 1.0%, 2.0% and 4.0%). Root length, microbial populations and numbers in the rhizosphere were also measured in this work. The results showed that there was significantly (premediation plants, there was a much higher removal of saturated hydrocarbon compared with other components. The biomass of P. nil L. did not decrease significantly when the concentration of petroleum hydrocarbons in soil was ≤2.0%. The trends of microbial populations and numbers in the rhizosphere were similar to the biomass changes, with the exception that fungi at 0.5% petroleum contaminated soil had the largest microbial populations and numbers. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. Corn (Zea mays growth in petroleum contaminated soil, remediated with orange (Citrus sinensis peel extract

    Directory of Open Access Journals (Sweden)

    Tomás Darío Marín Veláquez

    2016-09-01

    Full Text Available Soil pollution has a strong impact when oil activity takes place within a savanna ecosystem. Any oil spill affects agricultural soils. Biostimulation with orange peel extract (Citrus sinensis is an alternative for remediation of soil contaminated with crude oil and in this research the corn plant (Zea mays was used as a biomarker of contamination level of a savanna soil after their treatment. Three samples of savannah soil contaminated with oil light crude were treated with dissolutions 1, 3 and 5% of extract of orange peel in water at a dose of 150 mL per kg of soil treated. The content of oils and fats was measured every 7 days, up to 42 days. Corn seeds were planted in soil samples, their growth was measured every 5 days for a period of 35 consecutive days, comparing their growth with seeds planted in a soil sample without contamination. According to an analysis of rank contrast, the plant growth was statistically the same in all samples up to 20 days; from there, evident differences regarding the pattern were shown.

  7. Soil contamination of heavy metals in the Katedan Industrial Development Area, Hyderabad, India.

    Science.gov (United States)

    Govil, P K; Sorlie, J E; Murthy, N N; Sujatha, D; Reddy, G L N; Rudolph-Lund, Kim; Krishna, A K; Rama Mohan, K

    2008-05-01

    . However, the availability is considerably less than anthropogenic contaminants and must therefore be assessed differently. The pre- and post-monsoon sampling over two hydrological cycles in 2002 and 2003 indicate that the As, Cd and Pb contaminants are more mobile and may expect to reach the groundwater. The other contaminants seem to be much more stable. The contamination is especially serious in the industrial area as it is housing a large permanent residing population. The study not only aims at determining the natural background levels of trace elements as a guide for future pollution monitoring but also focuses on the pollution vulnerability of the watershed. A plan of action for remediation is recommended.

  8. Chemical and biological methods for the analysis and remediation of environmental contaminants frequently identified at superfund sites

    Energy Technology Data Exchange (ETDEWEB)

    Melinda Christine Wiles [Texas A& amp; M University, College Station, TX (United States). Department of Veterinary Anatomy & Public Health

    2004-08-15

    Substantial environmental contamination has occurred from coal tar creosote and pentachlorophenol (C5P) in wood preserving solutions. The present studies focused on the characterization and remediation of these contaminants. The first objective was to delineate a sequence of biological changes caused by chlorinated phenol (CP) exposure. The second study was to develop multi-functional sorbents to remediate CPs and other components of wood preserving waste from groundwater. Following water remediation, the final aim of this work was to explore the safety of the parent clay minerals as potential enterosorbents for contaminants ingested in water and food. Based on evaluations of toxicity and neutron activation analysis of tissues, no significant differences were observed between animals receiving clay supplements and control animals, with the exception of slightly decreased brain Rb in animals ingesting clay. Overall, the results suggest that neither clay mineral, at relatively high dietary concentrations, influences mineral uptake or utilization in the pregnant rat. 420 refs., 28 figs, 15 tabs.

  9. The effect of a zero-concentration sink on contaminant transport and remedial-action designs for the Weldon Spring quarry, Weldon Spring, Missouri

    Energy Technology Data Exchange (ETDEWEB)

    Tomasko, D.

    1990-04-01

    One-dimensional analytical expressions are developed to simulate two processes in a homogeneous porous medium: contaminant transport through a porous medium that has a zero-concentration sink located at a finite distance from a step-function source; and contaminant transport through a porous medium that has an initial steady-state distribution corresponding to a constant strength source and zero-concentration sink separated by a finite distance. The governing equations are cast in dimensionless form, making use of the flow system's Peclet number. Evaluation of the analytical expressions is accomplished by numerical inversion of Laplace-space concentrations using either a full Fourier series approach with acceleration, or the Stehfest algorithm. The analytical expressions are used to evaluate possible contaminant conditions at the Weldon Spring quarry near Weldon Spring, Missouri. The following results have been found: contaminant concentrations should be at or near steady-state conditions; the spatial distribution of contaminants should be a function of the flow system's Peclet number; contaminant concentrations near the Femme Osage Slough should approach zero; contaminant concentrations near the quarry during dewatering and bulk-waste removal should monotonically decrease with time; and the spatial distribution of contaminants during remedial activities should be relatively flat, especially near the dewatering pumps. Future work will entail evaluating existing radionuclide or chemical concentration data to determine the applicability of the proposed contaminant transport model and to improve the hydrogeological conceptualization of the quarry area and vicinity. 20 refs., 27 figs.

  10. Occupational safety during the remediation of a contaminated site: monitoring of PCDD/PCDF levels in blood of employees

    Energy Technology Data Exchange (ETDEWEB)

    Rottler, H. [Eurofins Oekometric, Bayreuth (Germany); Uffinger, H. [Tiefbau-Berufsgenossenschaft (TBG), Arbeitsmedizinischer Dienst, Frankfurt/Main (Germany)

    2004-09-15

    In connection with road construction activities a dioxin contaminated site was discovered during the 1990's in a German city, containing residues of early industrial activities. PCDD/PCDF levels up to 41 ng I-TEQ/g dry matter could be detected in the material with a 1,2,3,4,7,8-HxCDF dominated pattern. This pattern is very similar to samples related to the production and use of chlorine in the early 20{sup th} century. Furthermore, sandy material showing a deviating and 1,2,3,7,8-PeCDF dominated pattern with an at least a factor of 10 lower concentrations was found. A remediation program was initiated including removal of contaminated soil and installing a drainage layer below the final asphalt layer sealing the site. Occupational safety for employees involved in any on-site activities was of primary importance following regulations for work in contaminated areas and for preventive occupational medicine. Hygiene was strictly obeyed. On-site monitoring via chromatographic dust analysis was performed by surveying engineers. Employees working in contaminated areas wore Air-Filters A2P3 with motor support. The mandatory personal safety equipment included dust-proof protective suits for single use, chemical-proof gloves and boots. In this context, it was the task of the Employer's Liability Insurance Association (Tiefbau- Berufsgenossenschaft, TBG) to strictly control compliance of occupational safety measures. The occupational medical service of this association was commissioned monitoring the health situation of the employees involved. Among other parameters, the corresponding control program included monitoring of PCDD/PCDF blood levels to identify possible alterations.

  11. Optimizing Metalloporphyrin-Catalyzed Reduction Reactions for In Situ Remediation of DOE Contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Schlautman, Mark A. [Clemson University, Clemson, SC (United States)

    2013-07-14

    Past activities have resulted in a legacy of contaminated soil and groundwater at Department of Energy facilities nationwide. Uranium and chromium are among the most frequently encountered and highest-priority metal and radionuclide contaminants at DOE installations. Abiotic chemical reduction of uranium and chromium at contaminated DOE sites can be beneficial because the reduced metal species are less soluble in water, less mobile in the environment, and less toxic to humans and ecosystems. Although direct biological reduction has been reported for U(VI) and Cr(VI) in laboratory studies and at some field sites, the reactions can sometimes be slow or even inhibited due to unfavorable environmental conditions. One promising approach for the in-situ remediation of DOE contaminants is to develop electron shuttle catalysts that can be delivered precisely to the specific subsurface locations where contaminants reside. Previous research has shown that reduction of oxidized organic and inorganic contaminants often can be catalyzed by electron shuttle systems. Metalloporphyrins and their derivatives are well known electron shuttles for many biogeochemical systems, and thus were selected to study their catalytic capabilities for the reduction of chromium and uranium in the presence of reducing agents. Zero valent iron (ZVI) was chosen as the primary electron donor in most experimental systems. Research proceeded in three phases and the key findings of each phase are reported here. Phase I examined Cr(VI) reduction and utilized micro- and nano-sized ZVI as the electron donors. Electron shuttle catalysts tested were cobalt- and iron-containing metalloporphyrins and Vitamin B12. To aid in the recycle and reuse of the nano-sized ZVI and soluble catalysts, sol-gels and calcium-alginate gel beads were tested as immobilization/support matrices. Although the nano-sized ZVI could be incorporated within the alginate gel beads, preliminary attempts to trap it in sol-gels were not

  12. Sea Floor Topography and Backscatter Intensity of the Historic Area Remediation Site

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set includes topography and backscatter intensity of the sea floor of the Historic Area Remediation Site (HARS), located offshore of New York and New...

  13. Some aspects of the state of the art of contaminated sites remediation in Italy

    Directory of Open Access Journals (Sweden)

    Giovanni Pietro Beretta

    2015-06-01

    Full Text Available The remediation of contaminated sites has been faced in Italy and elsewhere in the world with a series of works originated by the availability of specific technologies for the recovery of soils and groundwater quality, acting in accordance with the principle of sustainability. A framework of rules (target values and type of intervention and a summary of the quality of soil and groundwater in Italian contaminated sites must be mentioned first. The design of the remediation was also permitted by the improvement of the site characterization, with specific equipments addressed for example to identify the stratigraphy of the contaminants, the presence of volatile compounds, the sampling of water of significant groundwater quality, etc.. The text describes some interventions relating to physical and hydraulic barriers that involve substantial capital and O&M costs and also the consumption of natural resources. Subsequently they are also considered important in situ interventions that resulted in a reduction in the concentration and significant recovery of the pollutants mass. The evolution of the residual concentration in the groundwater must be considered by monitoring natural attenuation. Despite the recovery of the mass of pollutants even up to 90-99%, values of cleanup (expected concentrations of the order of μg/L which are established by national legislation have not been achieved. It can be stated that the scientific community is considering the new paradigm expressed by the “order of magnitude of the flow of pollutant mass” to replace the old paradigm consisting in the “limit value of final concentrations”.

  14. Effects of initial solute distribution on contaminant availability, desorption modeling, and subsurface remediation.

    Science.gov (United States)

    Haws, Nathan W; Ball, William P; Bouwer, Edward J

    2007-01-01

    Low permeability regions in which solute movement is governed by diffusion reduce the availability of pollutants for remediation and can function as long-term sources of groundwater contamination. The inherent difficulty in understanding mass transfer from these regions of sequestered contamination is further complicated by unknown solute distributions within the low-permeability regions (sequestering regions). When models are calibrated to reproduce temporal histories of solute release from a sequestering region (desorption), the fitted parameter values are used to infer the physical or chemical characteristics of the media; however, the calibrated parameters also reflect the case-specific initial conditions (i.e., the solute distribution within the sequestering region domain at the onset of desorption). This phenomenon is demonstrated using model simulations of solute diffusion from hypothetical solids with characteristics similar to those of the well studied Borden, Ontario aquifer system. Solute release from the solids is simulated using a batch diffusion model under different initial solute distributions within the solids. The results of these model simulations are used to calibrate parameters of a multiple first-order rate desorption model (MRM) to illustrate how the fitted MRM parameters increase or decrease depending on the initial "aging" of the solids. Further numerical simulations are conducted for a one-dimensional flow system under steady-state and variable-rate hydraulic flushing. These simulations show that although aging reduces desorptive mass flux during early stages of flushing, aged sites have greater desorptive mass flux (greater solute availability) than "freshly" contaminated media during the later stages of remediation. Overall, the results demonstrate why the physicochemical meaning of observed desorption rates cannot be accurately deduced without first understanding the initial solute distribution within the media.

  15. An evaluation of different soil washing solutions for remediating arsenic-contaminated soils.

    Science.gov (United States)

    Wang, Yiwen; Ma, Fujun; Zhang, Qian; Peng, Changsheng; Wu, Bin; Li, Fasheng; Gu, Qingbao

    2017-04-01

    Soil washing is a promising way to remediate arsenic-contaminated soils. Most research has mostly focused on seeking efficient extractants for removing arsenic, but not concerned with any changes in soil properties when using this technique. In this study, the removal of arsenic from a heavily contaminated soil employing different washing solutions including H3PO4, NaOH and dithionite in EDTA was conducted. Subsequently, the changes in soil physicochemical properties and phytotoxicity of each washing technique were evaluated. After washing with 2 M H3PO4, 2 M NaOH or 0.1 M dithionite in 0.1 M EDTA, the soil samples' arsenic content met the clean-up levels stipulated in China's environmental regulations. H3PO4 washing decreased soil pH, Ca, Mg, Al, Fe, and Mn concentrations but increased TN and TP contents. NaOH washing increased soil pH but decreased soil TOC, TN and TP contents. Dithionite in EDTA washing reduced soil TOC, Ca, Mg, Al, Fe, Mn and TP contents. A drastic color change was observed when the soil sample was washed with H3PO4 or 0.1 M dithionite in 0.1 M EDTA. After adjusting the soil pH to neutral, wheat planted in the soil sample washed by NaOH evidenced the best growth of all three treated soil samples. These results will help with selecting the best washing solution when remediating arsenic-contaminated soils in future engineering applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Orthographic contamination of Broca’s area.

    Directory of Open Access Journals (Sweden)

    Marie eMontant

    2011-12-01

    Full Text Available Strong evidence has accumulated over the past years suggesting that orthography plays a role in spoken language processing. It is still unclear, however, whether the influence of orthography on spoken language results from a co-activation of posterior brain areas dedicated to low-level orthographic processing or whether it results from orthographic restructuring of phonological representations located in the anterior perisylvian speech network itself. To test these hypotheses, we ran a fMRI study that tapped orthographic processing in the visual and auditory modalities. As a marker for orthographic processing, we used the orthographic decision task in the visual modality and the orthographic consistency effect in the auditory modality. Results showed no specific orthographic activation neither for the visual nor the auditory modality in left posterior occipito-temporal brain areas that are thought to host the visual word form system. In contrast, specific orthographic activation was found both for the visual and auditory modalities at anterior sites belonging to the perisylvian region: the left dorsal-anterior insula and the left IFG. These results are in favor of the restructuring hypothesis according to which learning to read acts like a virus that permanently contaminates the spoken language system.

  17. Screening of contaminants in Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, B.G.; Frank, M.L.; Hoffman, F.O.; Hook, L.A.; Suter, G.W.; Watts, J.A.

    1992-09-01

    The purpose of this report is to present the results of a health risk and ecological risk screening analysis for Waste Area Grouping 2 (WAG 2) using available data to identify contaminants and environmental pathways that will require either further investigation or immediate consideration for remediation based on the screening indices. The screening analysis will also identify contaminants that can be assigned a low priority for further investigation and those that require additional data.

  18. Can energy willow (Salix sp.) remediate cadmium- and nickel-contaminated fish farm sludge?

    DEFF Research Database (Denmark)

    Pedersen, Marianne Bruus

    In Denmark, the sludge produced in fish farms is usually applied as agricultural fertiliser. However, in some areas of Denmark, the cadmium and nickel contents of the fish farm sludge exceed the Danish quality criteria for sludge, which means that the sludge has to be deposited or remedied until...... it meets the criteria. Phytoremediation by willow may combine accumulation of cadmium and nickel from the sludge with the production of an energy crop. The ability of eight selected willow clones to take up and tolerate cadmium and nickel was studied in pots under outdoor conditions. Fish farm sludge...... was added to the pots at different dosages, either on the soil surface, mixed into the soil or as pure sludge. The remediation potential of the single clones was estimated after one growing season by multiplying growth and heavy metal content. At leaf-fall leaves were collected for cadmium and nickel...

  19. Bioleaching remediation of heavy metal-contaminated soils using Burkholderia sp. Z-90.

    Science.gov (United States)

    Yang, Zhihui; Zhang, Zhi; Chai, Liyuan; Wang, Yong; Liu, Yi; Xiao, Ruiyang

    2016-01-15

    Bioleaching is an environment-friendly and economical technology to remove heavy metals from contaminated soils. In this study, a biosurfactant-producing strain with capacity of alkaline production was isolated from cafeteria sewer sludge and its capability for removing Zn, Pb, Mn, Cd, Cu, and As was investigated. Phylogenetic analysis using 16S rDNA gene sequences confirmed that the strain belonged to Burkholderia sp. and named as Z-90. The biosurfactant was glycolipid confirmed by thin layer chromatography and Fourier-transform infrared spectroscopy. Z-90 broth was then used for bioleaching remediation of heavy metal-contaminated soils. The removal efficiency was 44.0% for Zn, 32.5% for Pb, 52.2% for Mn, 37.7% for Cd, 24.1% for Cu and 31.6% for As, respectively. Mn, Zn and Cd were more easily removed from soil than Cu, Pb and As, which was attributed to the presence of high acid-soluble fraction of Mn, Zn and Cd and high residual fraction of Cu, Pb and As. The heavy metal removal in soils was contributed to the adhesion of heavy metal-contaminated soil minerals with strain Z-90 and the formation of a metal complex with biosurfactant.

  20. [Remediation of Cu-Pb-contaminated loess soil by leaching with chelating agent and biosurfactant].

    Science.gov (United States)

    Liu, Xia; Wang, Jian-Tao; Zhang, Meng; Wang, Li; Yang, Ya-Ti

    2013-04-01

    Because of its strong chelation, solubilization characteristics, the chelating agents and biosurfactant are widely used in remediation of heavy metals and organic contaminated soils. Ethylenediamine tetraacetic acid (EDTA), citric acid (CIT) and dirhamnolipid (RL2) were selected as the eluent. Batch experiments and column experiments were conducted to investigate the leaching effect of the three kinds of eluent, as well as the mixture of biosurfactant and chelating agent for Cu, Pb contaminated loess soil. The results showed that the leaching efficiencies of different eluent on Cu, Pb contaminated loess soil followed the sequence of EDTA > CIT > RL2. At an eluent concentration of 0.02 mol x L(-1), the Cu leaching efficiency was 62.74% (EDTA), 52.28% (CIT) and 15.35% (RL2), respectively; the Pb leaching efficiency was 96.10% (EDTA), 23.08% (CIT) and 14.42% (RL2), respectively. When the concentration of RL2 was 100 CMC, it had synergistic effects on the other two kinds of chelating agent in Cu leaching, and when the concentration of RL2 was 200 CMC, it had antagonism effects. The effect of RL2 on EDTA in Pb leaching was similar to that in Cu leaching. Pb leaching by CIT was inhibited in the presence of RL2. EDTA and CIT could effectively remove Cu and Pb in exchangeable states, adsorption states, carbonate salts and organic bound forms; RL2 could effectively remove Cu and Pb in exchangeable and adsorbed states.

  1. Remediation of soils contaminated with particulate depleted uranium by multi stage chemical extraction.

    Science.gov (United States)

    Crean, Daniel E; Livens, Francis R; Sajih, Mustafa; Stennett, Martin C; Grolimund, Daniel; Borca, Camelia N; Hyatt, Neil C

    2013-12-15

    Contamination of soils with depleted uranium (DU) from munitions firing occurs in conflict zones and at test firing sites. This study reports the development of a chemical extraction methodology for remediation of soils contaminated with particulate DU. Uranium phases in soils from two sites at a UK firing range, MOD Eskmeals, were characterised by electron microscopy and sequential extraction. Uranium rich particles with characteristic spherical morphologies were observed in soils, consistent with other instances of DU munitions contamination. Batch extraction efficiencies for aqueous ammonium bicarbonate (42-50% total DU extracted), citric acid (30-42% total DU) and sulphuric acid (13-19% total DU) were evaluated. Characterisation of residues from bicarbonate-treated soils by synchrotron microfocus X-ray diffraction and X-ray absorption spectroscopy revealed partially leached U(IV)-oxide particles and some secondary uranyl-carbonate phases. Based on these data, a multi-stage extraction scheme was developed utilising leaching in ammonium bicarbonate followed by citric acid to dissolve secondary carbonate species. Site specific U extraction was improved to 68-87% total U by the application of this methodology, potentially providing a route to efficient DU decontamination using low cost, environmentally compatible reagents.

  2. 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

  3. Application of biodegradation in mitigating and remediating pesticide contamination of freshwater resources: state of the art and challenges for optimization.

    Science.gov (United States)

    Vandermaesen, Johanna; Horemans, Benjamin; Bers, Karolien; Vandermeeren, Pieter; Herrmann, Steffi; Sekhar, Aswini; Seuntjens, Piet; Springael, Dirk

    2016-09-01

    In recent years, the application of pesticide biodegradation in remediation of pesticide-contaminated matrices moved from remediating bulk soil to remediating and mitigating pesticide pollution of groundwater and surface water bodies. Specialized pesticide-degrading microbial populations are used, which can be endogenous to the ecosystem of interest or introduced by means of bioaugmentation. It involves (semi-)natural ecosystems like agricultural fields, vegetated filter strips, and riparian wetlands and man-made ecosystems like on-farm biopurification systems, groundwater treatment systems, and dedicated modules in drinking water treatment. Those ecosystems and applications impose challenges which are often different from those associated with bulk soil remediation. These include high or extreme low pesticide concentrations, mixed contamination, the presence of alternative carbon sources, specific hydraulic conditions, and spatial and temporal variation. Moreover, for various indicated ecosystems, limited knowledge exists about the microbiota present and their physiology and about the in situ degradation kinetics. This review reports on the current knowledge on applications of biodegradation in mitigating and remediating freshwater pesticide contamination. Attention is paid to the challenges involved and current knowledge gaps for improving those applications.

  4. A fuzzy analytic network process for multi-criteria evaluation of contaminated site remedial countermeasures.

    Science.gov (United States)

    Promentilla, Michael Angelo B; Furuichi, T; Ishii, K; Tanikawa, N

    2008-08-01

    The Analytic Network Process (ANP) has been proposed to incorporate interdependence and feedback effect in the prioritization of remedial countermeasures using a hierarchical network decision model, but this approach seems to be incapable of capturing the vagueness and fuzziness during value judgment elicitation. The aim of this paper is to present an evaluation method using a fuzzy ANP (FANP) approach to address this shortcoming. Triangular fuzzy numbers (TFN) and their degree of fuzziness are used in the semantic scale as human judgment expressed in natural language is most often vague and fuzzy. The method employs the alpha-cuts, interval arithmetic and optimism index to transform the fuzzy comparative judgment matrix into set of crisp matrices, and then calculates the desired priorities using the eigenvector method. A numerical example, which was drawn from a real-life case study of an uncontrolled landfill in Japan, is presented to demonstrate the process. Results from the sensitivity analysis describe how the fuzziness in judgment could affect the solution robustness of the prioritization method. The proposed FANP approach therefore could effectively deal with the uncertain judgment inherent in the decision making process and derive the meaningful priorities explicitly from a complex decision structure in the evaluation of contaminated site remedial countermeasures.

  5. Glyphosate contaminated soil remediation by atmospheric pressure dielectric barrier discharge plasma and its residual toxicity evaluation.

    Science.gov (United States)

    Wang, Tiecheng; Ren, Jingyu; Qu, Guangzhou; Liang, Dongli; Hu, Shibin

    2016-12-15

    Glyphosate was one of the most widely used herbicides in the world. Remediation of glyphosate-contaminated soil was conducted using atmospheric pressure dielectric barrier discharge (DBD) plasma. The feasibility of glyphosate degradation in soil was explored, and the soil leachate toxicity after remediation was assessed via a seed germination test. The experimental results showed that approximately 93.9% of glyphosate was degraded within 45min of DBD plasma treatment with an energy yield of 0.47gkWh(-1), and the degradation process fitted the first-order kinetic model. Increasing the discharge voltage and decreasing the organic matter content of the soil were both found to facilitate glyphosate degradation. There existed appropriate soil moisture to realize high glyphosate degradation efficiency. Glyphosate mineralization was confirmed by changes of total organic carbon (TOC), chemical oxygen demand (COD), PO4(3-) and NO3(-). The degradation intermediates including glycine, aminomethylphosphonic acid, acetic acid, formic acid, PO4(3-) and NO3(-), CO2 and CO were observed. A possible pathway for glyphosate degradation in the soil using this system was proposed. Based on the soil leachate toxicity test using wheat seed germination, the soil did not exhibit any hazardous effects following high-efficiency glyphosate degradation.

  6. Remediation application strategies for depleted uranium contaminated soils at the US Army Yuma Proving Ground

    Energy Technology Data Exchange (ETDEWEB)

    Vandel, D.S.; Medina, S.M.; Weidner, J.R.

    1994-03-01

    The US Army Yuma Proving Ground (YPG), located in the southwest portion of Arizona conducts firing of projectiles into the Gunpoint (GP-20) firing range. The penetrators are composed of titanium and DU. The purpose of this project was to determine feasible cleanup technologies and disposal alternatives for the cleanup of the depleted uranium (DU) contaminated soils at YPG. The project was split up into several tasks that include (a) collecting and analyzing samples representative of the GP-20 soils, (b) evaluating the data results, (c) conducting a literature search of existing proven technologies for soil remediation, and (0) making final recommendations for implementation of this technology to the site. As a result of this study, several alternatives for the separation, treatment, and disposal procedures are identified that would result in meeting the cleanup levels defined by the Nuclear Regulatory Commission for unrestricted use of soils and would result in a significant cost savings over the life of the firing range.

  7. Reduction of radioactive waste from remediation of uranium-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Il Gook; Kim, Seung Soo; Kim, Gye Nam; Han, Gyu Seong; Choi, Jong Won [Decontamination and Decommissioning Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-06-15

    Great amounts of solid radioactive waste (second waste) and waste solution are generated from the remediation of uranium-contaminated soil. To reduce these, we investigated washing with a less acidic solution and recycling the waste solution after removal of the dominant elements and uranium. Increasing the pH of the washing solution from 0.5 to 1.5 would be beneficial in terms of economics. A high content of calcium in the waste solution was precipitated by adding sulfuric acid. The second waste can be significantly reduced by using sorption and desorption techniques on ampholyte resin S-950 prior to the precipitation of uranium at pH 3.0.

  8. Integrated Nanozero Valent Iron and Biosurfactant-Aided Remediation of PCB-Contaminated Soil

    Directory of Open Access Journals (Sweden)

    He Zhang

    2016-01-01

    Full Text Available Polychlorobiphenyls (PCBs have been identified as environmental hazards for years. Due to historical issues, a considerable amount of PCBs was released deep underground in Canada. In this research, a nanoscale zero valent iron- (nZVI- aided dechlorination followed by biosurfactant enhanced soil washing method was developed to remove PCBs from soil. During nZVI-aided dechlorination, the effects of nZVI dosage, initial pH level, and temperature were evaluated, respectively. Five levels of nZVI dosage and two levels of initial pH were experimented to evaluate the PCB dechlorination rate. Additionally, the temperature changes could positively influence the dechlorination process. In soil washing, the presence of nanoiron particles played a key role in PCB removal. The crude biosurfactant was produced using a bacterial stain isolated from the Atlantic Ocean and was applied for soil washing. The study has led to a promising technology for PCB-contaminated soil remediation.

  9. Remediation of subsurface and groundwater contamination with uranium from fuel fabrication facilities at Hanau (Germany)

    Energy Technology Data Exchange (ETDEWEB)

    Nitzsche, Olaf; Thierfeldt, Stefan [Brenk Systemplanung GmbH, Aachen (Germany); Hummel, Lothar [TUV Sud AG, Munchen (Germany)

    2013-07-01

    This paper presents aspects of site decommissioning and clearance of a former fuel fabrication facility (development and production of fuel assemblies for research reactors and HTR) at Hanau (Germany). The main pathways for environmental contamination were deposition on soil surface and topsoil and pollution of deep soil and the aquifer by waste water channel leakage. Soil excavation could be done by classical excavator techniques. An effective removal of material from the saturated zone was possible by using advanced drilling techniques. A large amount of demolished building structure and excavated soil had to be classified. Therefore the use of conveyor detector was necessary. Nearly 100000 Mg of material (excavated soil and demolished building material) were disposed of at an underground mine. A remaining volume of 700 m{sup 3} was classified as radioactive waste. Site clearance started in 2006. Groundwater remediation and monitoring is still ongoing, but has already provided excellent results by reducing the remaining Uranium considerably. (authors)

  10. Remediation of copper contaminated soil by using different particle sizes of apatite: a field experiment.

    Science.gov (United States)

    Xing, Jinfeng; Hu, Tiantian; Cang, Long; Zhou, Dongmei

    2016-01-01

    The particle size of apatite is one of the critical factors that influence the adsorption of heavy metals on apatite in the remediation of heavy metal contaminated soils using apatite. However, little research has been done evaluating the impact of different particle sizes of apatite on immobilization remediation of heavy metal polluted soils in field. In this study, the adsorption isothermal experiments of copper on three kinds of apatite was tested, and the field experiment by using different particle sizes apatite [nano-hydroxyapatite (NAP), micro-hydroxyapatite (MAP), ordinary particle apatite (OAP)] at a same dosage of 25.8 t/ha (1.16 %, W/W) was also conducted. Ryegrass was chosen as the test plant. The ryegrass biomass, the copper contents in ryegrass and the copper fractionations in soil were determined after field experiments. Results of adsorption experiments showed that the adsorption amounts of copper on OAP was the lowest among different particles. The adsorption amounts of copper on MAP was higher than NAP at high copper equilibrium concentration (>1 mmol L(-1)), an opposite trend was obtained at low copper concentration (soil pH, decrease the available copper concentration in soil, provide more nutrient phosphate and promote the growth of ryegrass. The ryegrass biomass and the copper accumulation in ryegrass were the highest in MAP among all treatments. The effective order of apatite in phytoremediation of copper contaminated field soil was MAP > NAP > OAP, which was attributed to the high adsorption capacity of copper and the strong releasing of phosphate by MAP.

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

    Science.gov (United States)

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

    2009-12-01

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

  12. Legacy contaminant bioaccumulation in rock crabs in Sydney Harbour during remediation of the Sydney Tar Ponds, Nova Scotia, Canada.

    Science.gov (United States)

    Walker, Tony R; MacAskill, Devin; Weaver, Peter

    2013-12-15

    Concentrations of PAHs, PCBs, metals and lipids in hepatopancreas of rock crabs (Cancer irroratus) were measured in Sydney Harbour (SH) for one year prior to remediation and three years of remediation of the Sydney Tar Ponds (STP), Nova Scotia. Low level concentrations of PCBs and metals were measured, although PAHs were mostly undetected. Metal concentrations showed little spatio-temporal variability, although highest concentrations of As, Cd and Cu were measured at reference stations furthest from the STP remediation site. Mercury concentrations were at least an order of magnitude lower than Canadian guidelines. Moderately elevated PCB concentrations were detected in crabs near Muggah Creek, but these were generally not higher than those measured during baseline. Despite remediation activities, current contaminant burdens measured in crabs were much lower than previously reported in other studies of crabs and lobster in industrial harbours in eastern Canada, due in part to natural recovery of SH sediments.

  13. An experimental study on the bio-surfactant-assisted remediation of crude oil and salt contaminated soils.

    Science.gov (United States)

    Zhang, Wen; Li, Jianbing; Huang, Guohe; Song, Weikun; Huang, Yuefei

    2011-01-01

    The effect of bio-surfactant (rhamnolipid) on the remediation of crude oil and salt contaminated soil was investigated in this study. The experimental results indicated that there was a distinct decline of total petroleum hydrocarbon (TPH) concentration within the soil when using rhamnolipid during a remediation period of 30 days, with maximum TPH reduction of 86.97%. The most effective remediation that was observed was with rhamnolipid at a concentration of 2 CMC in soil solution, and a first-order TPH degradation rate constant of 0.0866 d(-1). The results also illustrated that salts in soil had a negative impact on TPH reduction, and the degradation rate was negatively correlated with NaCl concentration in soil solution. The analysis of soil TPH fractions indicated that there was a significant reduction of C13-C30 during the remediation process when using bio-surfactant.

  14. Investigation of the Use of "Cucumis Sativus" for Remediation of Chromium from Contaminated Environmental Matrices: An Interdisciplinary Instrumental Analysis Project

    Science.gov (United States)

    Butler, Lynsey R.; Edwards, Michael R.; Farmer, Russell; Greenly, Kathryn J.; Hensler, Sherri; Jenkins, Scott E.; Joyce, J. Michael; Mann, Jason A.; Prentice, Boone M.; Puckette, Andrew E.; Shuford, Christopher M.; Porter, Sarah E. G.; Rhoten, Melissa C.

    2009-01-01

    An interdisciplinary, semester-long project is presented in which students grow Cucumis sativus (cucumber) plants from seeds and study the ability of the plants to remediate a heavy metal from contaminated soil or water or both. Phytoremediation strategies for environmental cleanup are presented as possible alternatives to chemical based clean-up…

  15. Feasibility study of the use of different extractant agents in the remediation of a mercury contaminated soil from Almaden

    DEFF Research Database (Denmark)

    Subirés-Muñoz, J.D.; García-Rubio, A.; Vereda-Alonso, C.

    2011-01-01

    polluted for several millennia. The risk assessment of the contamination and the feasibility study (RA-FS) of the remediation were based on a standard sequential extraction procedure (SEP) together with lixiviation tests. Results obtained from these RA-FSs allow the prediction of the mercury removal...

  16. Investigation of the Use of "Cucumis Sativus" for Remediation of Chromium from Contaminated Environmental Matrices: An Interdisciplinary Instrumental Analysis Project

    Science.gov (United States)

    Butler, Lynsey R.; Edwards, Michael R.; Farmer, Russell; Greenly, Kathryn J.; Hensler, Sherri; Jenkins, Scott E.; Joyce, J. Michael; Mann, Jason A.; Prentice, Boone M.; Puckette, Andrew E.; Shuford, Christopher M.; Porter, Sarah E. G.; Rhoten, Melissa C.

    2009-01-01

    An interdisciplinary, semester-long project is presented in which students grow Cucumis sativus (cucumber) plants from seeds and study the ability of the plants to remediate a heavy metal from contaminated soil or water or both. Phytoremediation strategies for environmental cleanup are presented as possible alternatives to chemical based clean-up…

  17. Treatability study report for remediation of chemical warfare agent contaminated soils using peroxysulfate ex-situ treatment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pugh, J.R.; Grinstead, J.H.; Farley, J.A.; Enlow, P.D.; Kelly, D.A.

    1996-07-01

    This laboratory scale study examines the feasibility of using peroxysulfate based oxidants to remediate soils contaminated with GB, Hi, and VX. The project was conducted with chemical warfare agent simulants. The study concludes that peroxysulfates, and particularly peroxydisulfate, can degrade chemical warfare agent simulants in soil and recommends continuing research.

  18. Remediation approach for organic compounds and arsenic co-contaminated soil using pressurized hot water extraction process.

    Science.gov (United States)

    Islam, Mohammad Nazrul; Jo, Young-Tae; Jeong, Yeon-Jae; Park, Jeong-Hun

    2017-09-15

    Successful remediation of soil with co-existing organics contaminants and arsenic (As) is a challenge as the chemical and remediation technologies are different for each group of pollutants. In this study, the treatment effectiveness of pressurized hot water (PHW) extraction process was investigated for remediation of soil co-contaminated with phenol, crude oil, polycyclic aromatic hydrocarbons (PAHs) and As. An elimination percentage of about 99% was achieved for phenol, and in the range of 63-100% was observed for the PAHs at 260 °C for 90 min operation. The performance of PHW extraction in the removal of total petroleum hydrocarbons was found to be 86%. Of the 87 mg/kg of As in untreated soil, 67% of which was eliminated after treatment. The removal of organic contaminants was mainly via desorption, dissolution and degradation in subcritical water, while As was eliminated probably by oxidation and dissolution of arsenic-bearing minerals. According to the experimental results, PHW extraction process can be suggested as an alternative cleaning technology, instead of using any organic solvents for remediation of such co-contaminated soil.

  19. Effects of soil organic matter and ageing on remediation of diesel-contaminated soil.

    Science.gov (United States)

    Liu, Pao-Wen Grace; Wang, Sih-Yu; Huang, Shen-Gzhi; Wang, Ming-Zhi

    2012-12-01

    Bioremediation of diesel-contaminated soil was investigated for the effects of soil organic matter (SOM) and ageing time in two sets of experiments (Batch I and II, respectively). This study examined degradation efficiency in soil artificially contaminated with diesel oil (maximum total petroleum hydrocarbons (TPH) concentration of 9000 mg/kg soil). Batch I data showed that the values of the first-order degradation rate, k, were relatively high in the low-SOM soil batches. The quantity of SOM negatively correlated with the TPH degradation rates and with the total TPH degradation efficiency (%). Introduction of rhamnolipid to the soil proved to be a useful solution to resolve the problem of the residual TPH in the soil with high SOM. In Batch II, the k values decreased with the length of ageing time: 0.0245, 0.0128 and 0.0090 l/d in samples ST0 (freshly contaminated), ST38 (aged for 38 days) and ST101 (aged for 101 days), respectively. The TPH degradation efficiency (%) also decreased along with the ageing time. The research also applied molecular technology to analyse the bacterial community dynamics during the bioremediation course. Multivariate statistics based on terminal-restriction fragment length data indicated: 1) the soils with different SOM resulted in separate bacterial community structures, 2) ageing time created a variety of bacterial communities, 3) the bacterial community dynamics was associated with the hydrocarbon consumption. The SOM content in soils affected the TPH degradation rate and efficiency and the bacterial community structures. Aged soil is more difficult to remediate than freshly contaminated soil, and the resulting bacterial community was less dynamic and showed a lack of succession.

  20. Remediation of Nitrate-contaminated Groundwater by a Mixture of Iron and Activated Carbon

    Science.gov (United States)

    Huang, Guoxin; Liu, Fei; Jin, Aifang; Qin, Xiaopeng

    2010-11-01

    Nitrate contamination in groundwater has become a major environmental and health problem worldwide. The aim of the present study is to remediate groundwater contaminated by nitrate and develop potential reactive materials to be used in PRBs (Permeable Reactive Barriers). A new approach was proposed for abiotic groundwater remediation by reactive materials of iron chips and granular activated carbon particles. Batch tests were conducted and remediation mechanisms were discussed. The results show that nitrate decreases from 86.31 to 33.79 mgṡL-1 under the conditions of near neutral pH and reaction time of 1h. The combination of iron chips and activated carbon particles is cost-effective and suitable for further use as denitrification media in PRBs. Nitrogen species don't change significantly with the further increase in reaction time (>1 h). The iron-activated carbon-water-nitrate system tends to be steady-state. Small amounts of ammonium and nitrite (0.033-0.039 and 0.14-3.54 mgṡL-1, respectively) appear at reaction time from 0 h to 5 h. There is no substantial accumulation of nitrogen products in the system. The removal rate of nitrate only reaches 16.11% by sole iron chips at reaction time of 5 h, while 63.57% by the mixture of iron chips and activated carbon particles. There is significantly synergistic and promotive effect of mixing the two different types of materials on nitrate treatment. Fe/C ratio (1/1.5-1/2.5) doesn't cause dramatically different residual nitrate concentrations (24.09-26.70 mgṡL-1). Nitrate can't be limitlessly decreased with decreasing Fe/C ratio. The concomitant occurrences of chemical reduction, galvanic cell reaction, electrophoretic accumulation, chemical coagulation, and physical adsorption are all responsible for the overall nitrate removal by iron allied with activated carbon. To accurately quantify various nitrogen species, further studies on adsorption mechanisms of nitrite and nitrate are needed.

  1. Radiation protection of radioactively contaminated large areas by phytoremediation and subsequent utilization of the contaminated plant residues (PHYTOREST); Massnahmen zur Strahlenschutzvorsorge radioaktiv belasteter Grossflaechen durch Sanierung mittels Phytoremediation und anschliessende Verwertung der belasteten Pflanzenreststoffe (PHYTOREST)

    Energy Technology Data Exchange (ETDEWEB)

    Mirgorodsky, Daniel; Ollivier, Delphine; Merten, Dirk; Bergmann, Hans; Buechel, Georg [Jena Univ. (Germany). Inst. fuer Geowissenschaften; Willscher, Sabine; Wittig, Juliane; Jablonski, Lukasz; Werner, Peter [Technische Univ. Dresden, Pirna (Germany). Inst. fuer Abfallwirtschaft und Altlasten

    2010-12-15

    Much progress has been achieved over the past 20 years in remediating sites contaminated by heavy metal. However, very large contaminated areas have presented major problems to this day because of remediation costs. Phytoremediation is a new, emerging, sustainable technique of remediating areas with low heavy-metal contamination. One advantage of phytoremediation is the comparatively low cost of the process, which may make it usable also on large areas with low levels of contamination. Besides extracting and immobilizing metals, respectively, phytoremediation among other things also contributes to improving soil quality in terms of physics, chemistry, and ecology. Consequently, phytoremediation offers a great potential for the future. Research into phytoremediation of an area contaminated by heavy metals and radionuclides is carried out on a site in a former uranium mining district in Eastern Thuringia jointly by the Friedrich Schiller University, Jena, and the Technical University of Dresden in a project funded by the German Federal Ministry for Education and Research. The project serves to promote the introduction of soft, biocompatible methods of long-term remediation and to develop conceptual solutions to the subsequent utilization of contaminated plant residues. Optimizing area management is in the focus of phytoremediation studies. (orig.)

  2. A study on the environmental and safety problems and their remediation around mining areas

    Energy Technology Data Exchange (ETDEWEB)

    Min, Jeong-Sik; Kang, Sun-Duck; Lee, Sang-Kwon [Korea Institute of Geology Mining and Materials, Taejon (KR)] (and others)

    1999-12-01

    The remediation or prevention of environmental problems and hazard around mining areas is required to prevent the natural environments and to protect human health. A survey were carried out to exam the characteristics of abandoned mines and to delineate contaminated sites in 4 abandoned mines (Imgee mine, Duckeum mine, Seosung mine and Jeonjuil mine). Permeability experiment was carried out to resolve clogging problems in passive treatment system. Absorption and desorption experiment was carried out to evaluate algae's ability for eliminating metals in mine drainage. In addition, a research on optimal mining method for reducing the area of forest damage in open pit mining areas was carried out. Results of permeability experiment showed that the coefficients of permeability of oak chips mixed with crushed limestone and coarse sand were 4.2 x 10{sup -2} cm/sec and 2.3 x 10{sup -2} cm/sec, respectively. As mine drainage upflowed through the column, metal hydroxide was intensively accumulated near the inlet and the outlet of columns. These phenomena contributed to lower the coefficient of permeability and caused clogging in columns. Further study on the optimal mixture of substrates for maintenance of constant flow and treatment for mine drainage in the wetland system will be required in order to prevent clogging caused by precipitation of metal hydroxides. The absorption test of algae for metals revealed that algae absorbed Fe, Cu and Al. Manganese was absorbed to the extend of 0.3 wt.% of dry algae. Therefore algae may be used for removal of Mn in passive treatment system. Plan Cut method was more superior to Bench Cut method in that the former could minimize the area of forest damage and reduce the mining environmental problems. (author). 19 refs., 39 tabs., 106 figs.

  3. [Evaluation of compounding EDTA and citric acid on remediation of heavy metals contaminated soil].

    Science.gov (United States)

    Yin, Xue; Chen, Jia-Jun; Cai, Wen-Min

    2014-08-01

    As commonly used eluents, Na2EDTA (EDTA) and citric acid (CA) have been widely applied in remediation of soil contaminated by heavy metals. In order to evaluate the removal of arsenic, cadmium, copper, and lead in the contaminated soil collected in a chemical plant by compounding EDTA and CA, a series of stirring experiments were conducted. Furthermore, the changes in speciation distribution of heavy metals before and after washing were studied. The results showed that, adopting the optimal molar ratio of EDTA/CA (1:1), when the pH of the solution was 3, the stirring time was 30 min, the stirring rate was 150 r x min(-1) and the L/S was 5:1, the removal rates of arsenic, cadmium, copper and lead could reach 11.72%, 43.39%, 24.36% and 27.17%, respectively. And it was found that after washing, for arsenic and copper, the content of acid dissolved fraction rose which increased the percentage of available contents. Fe-Mn oxide fraction mainly contributed to the removal of copper. As for cadmium, the percentages of acid dissolved fraction, Fe-Mn oxide fraction and organic fraction also decreased. In practical projects, speciation changes would pose certain environmental risk after soil washing, which should be taken into consideration.

  4. Remediation of PAH contaminated soils: application of a solid-liquid two-phase partitioning bioreactor.

    Science.gov (United States)

    Rehmann, Lars; Prpich, George P; Daugulis, Andrew J

    2008-10-01

    The feasibility of a two-step treatment process has been assessed at laboratory scale for the remediation of soil contaminated with a model mixture of polycyclic aromatic hydrocarbons (PAHs) (phenanthrene, pyrene, and fluoranthene). The initial step of the process involved contacting contaminated soil with thermoplastic, polymeric pellets (polyurethane). The ability of three different mobilizing agents (water, surfactant (Biosolve) and isopropyl alcohol) to enhance recovery of PAHs from soil was investigated and the results were compared to the recovery of PAHs from dry soil. The presence of isopropyl alcohol had the greatest impact on PAH recovery with approximately 80% of the original mass of PAHs in the soil being absorbed by the polymer pellets in 48 h. The second stage of the suggested treatment involved regeneration of the PAH loaded polymers via PAH biodegradation, which was carried out in a solid-liquid two-phase partitioning bioreactor. In addition to the PAH containing polymer pellets, the bioreactor contained a microbial consortium that was pre-selected for its ability to degrade the model PAHs and after a 14 d period approximately 78%, 62% and 36% of phenanthrene, pyrene, and fluoranthene, respectively, had been desorbed from the polymer and degraded. The rate of phenanthrene degradation was shown to be limited by mass transfer of phenanthrene from the polymer pellets. In case of pyrene and fluoranthene a combination of mass transfer and biodegradation rate might have been limiting.

  5. Remediation trials for hydrocarbon-contaminated sludge from a soil washing process: evaluation of bioremediation technologies.

    Science.gov (United States)

    Frutos, F J García; Pérez, R; Escolano, O; Rubio, A; Gimeno, A; Fernandez, M D; Carbonell, G; Perucha, C; Laguna, J

    2012-01-15

    The usual fate of highly contaminated fine products (silt-clay fractions) from soil washing plants is disposal in a dump or thermal destruction (organic contaminants), with consequent environmental impacts. Alternative treatments for these fractions with the aim of on-site reuse are needed. Therefore, the feasibility of two technologies, slurry bioremediation and landfarming, has been studied for the treatment of sludge samples with a total petroleum hydrocarbon (TPH) content of 2243 mg/kg collected from a soil washing plant. The treatability studies were performed at the laboratory and pilot-real scales. The bioslurry assays yielded a TPH reduction efficiency of 57% and 65% in 28 days at the laboratory and pilot scale, respectively. In the landfarming assays, a TPH reduction of 85% in six months was obtained at laboratory scale and 42% in three months for the bioremediation performed in the full-scale. The efficiency of these processes was evaluated by ecotoxicity assessments. The toxic effects in the initial sludge sample were very low for most measured parameters. After the remediation treatments, a decrease in toxic effects was observed in earthworm survival and in carbon mineralisation. The results showed the applicability of two well known bioremediation technologies on these residues, this being a novelty.

  6. Chitosan and alginate biopolymer membranes for remediation of contaminated water with herbicides.

    Science.gov (United States)

    Agostini de Moraes, Mariana; Cocenza, Daniela Sgarbi; da Cruz Vasconcellos, Fernando; Fraceto, Leonardo Fernandes; Beppu, Marisa Masumi

    2013-12-15

    This study investigated the adsorption behavior of the herbicides diquat, difenzoquat and clomazone on biopolymer membranes prepared with alginate and chitosan (pristine and multi-layer model) for contaminated water remediation applications. Herbicides, at concentrations ranging from 5 μM to 200 μM, were adsorbed in either pure alginate, pure chitosan or a bilayer membrane composed of chitosan/alginate. No adsorption of clomazone was observed on any of the membranes, probably due to lack of electrostatic interactions between the herbicide and the membranes. Diquat and difenzoquat were only adsorbed on the alginate and chitosan/alginate membranes, indicating that this adsorption takes place in the alginate layer. At a concentration of 50 μM, diquat adsorption reaches ca. 95% after 120 min on both the alginate and chitosan/alginate membranes. The adsorption of difenzoquat, at the same concentration, reaches ca. 62% after 120 min on pure alginate membranes and ca. 12% on chitosan/alginate bilayer membranes. The adsorption isotherms for diquat and difenzoquat were further evaluated using the isotherm models proposed by Langmuir and by Freundlich, where the latter represented the best-fit model. Results indicate that adsorption occurs via coulombic interactions between the herbicides and alginate and is strongly related to the electrostatic charge, partition coefficients and dissociation constants of the herbicides. Biopolymer based membranes present novel systems for the removal of herbicides from contaminated water sources and hold great promise in the field of environmental science and engineering.

  7. Remediation of cadmium contaminated vertisol mediated by Prosopis charcoal and coir pith

    Directory of Open Access Journals (Sweden)

    Palaninaicker Senthilkumar

    2015-01-01

    Full Text Available Metal contamination of soil due to industrial and agricultural activities is increasingly becoming a global problem, thereby affecting animal and human life, thus rendering soil unsuitable for agricultural purposes. Remediation of cadmium (Cd contaminated soil (Vertisol using agricultural by products as source of organic amendments, Coir pith- a by-product of the coir industry and Prosopis charcoal- prepared by burning Prosopis plant wood (Prosopis juliflora L. was investigated. The alleviation potential of Prosopis charcoal and Coir pith on the negative effects of Cd in soil was evaluated in pot culture experiments with Vigna radiata as the test plant, a Cd accumulator. Cadmium addition to soil resulted in accumulation of Cd in all plant parts of V. radiata predominantly in roots. The influence of Cd in the presence and absence of organic amendments on the various biological and chemical parameters of the soil, on the levels of Cd accumulation and on the growth attributes of V. radiata has been assessed. Among the organic amendments, Prosopis charcoal was found to be more effective in reducing the bioavailable levels of Cd in the soil artificially spiked with Cd in graded concentrations of 0, 5, 10, 20, 40, 60, 80 and 100 µg g-1 and its accumulation in V. radiata, thus resulting in an increase in the root, leaf and stem biomass. Coir pith, however, was effective in increasing the total mycorrhizal colonization of roots and second in reducing Cd levels in plants. Therefore, Prosopis charcoal was considered best for stabilization of Cd in soil.

  8. White Oak Creek watershed: Melton Valley area Remedial Investigation report, at the Oak Ridge National Laboratory, Oak Ridge, Tennessee: Volume 2, Appendixes A and B

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    This document contains Appendixes A ``Source Inventory Information for the Subbasins Evaluated for the White Oak Creek Watershed`` and B ``Human Health Risk Assessment for White Oak Creek / Melton Valley Area`` for the remedial investigation report for the White Oak Creek Watershed and Melton Valley Area. Appendix A identifies the waste types and contaminants for each subbasin in addition to the disposal methods. Appendix B identifies potential human health risks and hazards that may result from contaminants present in the different media within Oak Ridge National Laboratory sites.

  9. Remediation of contaminated soil using soil washing and biopile methodologies at a field level

    Energy Technology Data Exchange (ETDEWEB)

    Iturbe, R.; Flores, C.; Chavez, C.; Bautista, G.; Torres, L.G. [Inst. de Ingenieria, Univ. Nacional Autonoma de Mexico, Coordinacion de Ingenieria Ambiental, Grupo Saneamiento de Suelos y Acuiferos, Coyoacn, Mexico, D.F. (Mexico)

    2004-07-01

    Background, aims and scope. An out-of-service oil distribution and storage station (ODSS), which operated from 1966 to 2000 in Mexico, is contaminated mainly by gasoline and diesel, showing the presence of methyl-tert-butyl-ether, benzene, toluene, ethyl benzene, and xylenes. Nine of the 16 polycyclic aromatic hydrocarbons were found, as well as Fe, Pb, V, and Zn. The health risk assessment suggested the necessity of reducing of three PAHs [benzo(a)anthracene, benzo(a)pyrene, and benzo(b)fluoranthene], and vanadium. The aim of this work is to show that soil washing (on-site) and biopiles are excellent remediation methodologies to treat soils contaminated with petroleum derivates and metals. Applying them, it is possible to reach the goal value of 2,000 mg TPH/kg in a few months, as requested by Mexican legislation. Methods. More than 140 m{sup 3} were excavated from the ODSS. Three soil-washing dishes were built. 1540 m{sup 3} were treated by soil washing using a nonionic surfactant. A 100 m{sup 3} biopile was built to study the system capabilities in the biodegradation of around 4,500 mg/kg of TPH using the autochthonous microflora. Results and discussion. The soil washing, average TPH-removal value was 83%, but values up to ca. 93% were observed. Removal values resulted in a function of the TPH initial values. Biopile (100 m{sup 3}) worked during 66 days, reaching a TPH-removal value of 85%. At the end of the processes, no PAHs were detected. The contaminated soil was treated successfully, reaching the legislation limits (TPH values under 2,000 mg/kg, and a significant reduction in PAH concentrations). Conclusion and recommendation. Both systems are suitable for remediation purposes, achieving high removal efficiencies at short and medium stages. It is highly recommended to proceed with soil washing studies, identifying new products, and mixtures, which could reduce costs and assure optimum operation. (orig.)

  10. Simple indicator kriging for estimating the probability of incorrectly delineating hazardous areas in a contaminated site

    Energy Technology Data Exchange (ETDEWEB)

    Juang, K.W.; Lee, D.Y. [National Taiwan Univ., Taipei (Taiwan, Province of China). Graduate Inst. of Agricultural Chemistry

    1998-09-01

    The probability of incorrectly delineating hazardous areas in a contaminated site is very important for decision-makers because it indicates the magnitude of confidence that decision-makers have in determining areas in need of remediation. In this study, simple indicator kriging (SIK) was used to estimate the probability of incorrectly delineating hazardous areas in a heavy metal-contaminated site, which is located at Taoyuan, Taiwan, and is about 10 ha in area. In the procedure, the values 0 and 1 were assigned to be the stationary means of the indicator codes in the SIK model to represent two hypotheses, hazardous and safe, respectively. The spatial distribution of the conditional probability of heavy metal concentrations lower than a threshold, given each hypothesis, was estimated using SIK. Then, the probabilities of false positives ({alpha}) (i.e., the probability of declaring a location hazardous when it is not) and false negatives ({beta}) (i.e., the probability of declaring a location safe when it is not) in delineating hazardous areas for the heavy metal-contaminated site could be obtained. The spatial distribution of the probabilities of false positives and false negatives could help in delineating hazardous areas based on a tolerable probability level of incorrect delineation. In addition, delineation complicated by the cost of remediation, hazards in the environment, and hazards to human health could be made based on the minimum values of {alpha} and {beta}. The results suggest that the proposed SIK procedure is useful for decision-makers who need to delineate hazardous areas in a heavy metal-contaminated site.

  11. Phytoremediation and phytomining: Using plants to remediate contaminated or mineralized environments

    Science.gov (United States)

    One type of harsh environment for plants is metal and metalloid contaminated or mineralized soils which exist in most countries due to geological formations or to the history of mining and smelting. Depending on soil pH and fertility, metal-rich soils may be barren and eroding into wider areas. Some...

  12. A PERMEABLE ACTIVE AMENDMENT CONCRETE (PAAC) FOR CONTAMINANT REMEDIATION AND EROSION CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    Knox, A.; Paller, M.; Dixon, K.

    2012-06-29

    The final project report for SEED SERDP ER - 2134 describes the development of permeable active amendment concrete (PAAC), which was evaluated through four tasks: 1) development of PAAC; 2) assessment of PAAC for contaminant removal; 3) evaluation of promising PAAC formulations for potential environmental impacts; and 4) assessment of the hydraulic, physical, and structural properties of PAAC. Conventional permeable concrete (often referred to as pervious concrete) is concrete with high porosity as a result of an extensive and interconnected void content. It is made from carefully controlled amounts of water and cementitious materials used to create a paste that forms a coating around aggregate particles. The mixture has a substantial void content (e.g., 15% - 25%) that results in a highly permeable structure that drains quickly. In PAAC, the aggregate material is partly replaced by chemically-active amendments that precipitate or adsorb contaminants in water that flows through the concrete interstices. PAAC combines the relatively high structural strength, ample void space, and water permeability of pervious concrete with the contaminant sequestration ability of chemically-active amendments to produce a new material with superior durability and ability to control contaminant mobility. The high surface area provided by the concrete interstices in PAAC provides significant opportunity for contaminants to react with the amendments incorporated into the concrete matrix. PAAC has the potential to immobilize a large variety of organic and inorganic contaminants by incorporating different active sequestering agents including phosphate materials (rock phosphate), organoclays, zeolite, and lime individually or in combinations.

  13. 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.

  14. Remediation of PCB-contaminated soils. Risk analysis of biological in situ processes

    Energy Technology Data Exchange (ETDEWEB)

    Rein, Arno

    2006-12-08

    Biological in situ measures can be efficient and cost effective options for the remediation of contaminated sites. However, the accepted application requires a detailed and reliable analysis of potential impacts. An important objective is to quantify the potential of contaminant degradation and metabolite formation. This thesis addresses a quantitative multimedia risk assessment. Methodologies and tools were developed for this objective and applied to evaluate in situ bioremediation of soils contaminated with polychlorinated biphenyls (PCBs). Soil bacteria in conjunction with plant roots were addressed (rhizoremediation) with a focus on the use of genetically modified microorganisms (GMOs). PCBs are known to be harmful compounds that are ubiquitously distributed in the environment. PCB contaminations in soil and groundwater were identified as important problems. 209 different congeners are sterically possible, but not all are of environmental significance. PCB congeners of concern were evaluated with respect to their potential toxicity, environmental occurrence and mobility. For this objective, congener specific data on the toxicity potential and the frequency in environmental matrices were collected. To quantify the mobility potential, multimedia modelling was performed applying deterministic and probabilistic procedures. 56 PCB congeners of concern were evaluated, and multimedia risk assessments of PCB-contaminated soils should concentrate on this group. Kinetics parameters were specified for degradation experiments with individual PCB congeners in solution and different bacterial strains. These laboratory assays were performed with wild-type Burkholderia sp. strain LB400 and the genetically modified Pseudomonas fluorescens strains F113pcb and F113L::1180. The F113 derivatives demonstrated a good survival ability in willow (Salix sp.) rhizosphere (mesocosm experiments). Therefore, and due to high depletion rates, rhizoremediation with F113L::1180 and willow

  15. Evaluation of remedial options for a benzene-contaminated site through a simulation-based fuzzy-MCDA approach.

    Science.gov (United States)

    Yang, A L; Huang, G H; Qin, X S; Fan, Y R

    2012-04-30

    A simulation-based fuzzy multi-criteria decision analysis (SFMCDA) method is developed for supporting the selection of remediation strategies for petroleum contaminated sites. SFMCDA integrates process modeling (using BIOPLUME III) and fuzzy ranking (based on fuzzy TOPSIS) into a general management framework, and can compare various remediation alternatives, in light of both cost-risk tradeoffs and uncertainty impacts. The proposed method is applied to a hypothetical contaminated site suffering from a benzene leakage problem. Six remediation alternatives are taken into consideration, including natural attenuation (NA), pump-and-treat (PAT), enhanced natural attenuation (ENA), and a number of their combinations. Six fuzzy criteria, including both cost and risk information, are used to compare different alternatives through fuzzy TOPSIS. The results demonstrates that the proposed method can help systematically analyze fuzzy inputs from contaminant transport modeling, cost implications and stakeholders' preferences, and provide useful ranking information covering a variety of decision-relevant remediation options for decision makers. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  16. Proceedings of the 2005 conference on assessment and remediation of contaminated sites in Arctic and cold climates

    Energy Technology Data Exchange (ETDEWEB)

    Biggar, K.; Cotta, G.; Mullick, A.; Nahir, M.; Buchko, J.; Ho, A.; Guigard, S.; Goulden, W. (eds.)

    2005-07-01

    With increasing activity and interest in the diamond mines and oil and gas industry in Canada's Arctic along with increased activity in the Antarctic, Alaska and Russia, the exchange of knowledge concerning development in the Arctic and other cold climates has become increasing relevant. The presentations at this conference focused on the assessment and remediation of contaminated sites in colder climates and regions around the world. Issues concerning Aboriginal involvement in impact management and collaborative planning were reviewed. The development of risk assessment methodologies and new remediation approaches and techniques were examined, as well as new closure and decommissioning management strategies. Issues concerning landfills, water migration, engineering and geologic considerations and barrier systems were reviewed. Other topics of discussion included the development of site-specific environmental criteria, issues concerning the remediation of mines, new developments in soil remediation, hydrocarbon, chlorinated ethenes and soil nitrogen ratios. Key challenges include the effects of cold temperatures on maintenance and remedial effectiveness, as well as the accumulation of hydrocarbons in the soil at low temperatures. Remediation planning and logistical support issues were also discussed. A total of 42 papers were presented at this conference, of which 10 have been indexed separately for inclusion in this database. refs., tabs., figs.

  17. Waste management and contaminated site remediation practices after oil spill: a case study.

    Science.gov (United States)

    Oliveira, Fernando Jorge Santos; da Rocha Calixto, Renata Oliveira; Felippe, Carlos Eduardo Cunha; de Franca, Francisca Pessoa

    2013-12-01

    A case study is presented on waste management practices implemented after a residual fuel oil spill from a steam-generating boiler in an industrial area, and on the technical feasibility of monitored natural attenuation as a treatment option for a recently contaminated tropical soil. One day after contamination, surface soil total petroleum hydrocarbons and phenanthrene concentrations varied from 3.1 to 7.9 g kg(-1) and 149 to 287 µg kg(-1), respectively. Petroleum hydrocarbon concentrations decayed along the monitored time and after 90 days of processes the soil was considered rehabilitated for future industrial use.

  18. Induced metal redistribution and bioavailability enhancement in contaminated river sediment during in situ biogeochemical remediation.

    Science.gov (United States)

    Liu, Tongzhou; Zhang, Zhen; Mao, Yanqing; Yan, Dickson Y S

    2016-04-01

    In situ sediment remediation using Ca(NO3)2 or CaO2 for odor mitigation and acid volatile sulfide (AVS) and organic pollutant (such as TPH and PAHs) removal was reported in many studies and fieldwork. Yet, the associated effects on metal mobilization and potential distortion in bioavailability were not well documented. In this study, contaminated river sediment was treated by Ca(NO3)2 and CaO2 in bench studies. Through the investigation of AVS removal, organic matter removal, the changes in sediment oxidation-reduction potential (ORP), microbial activity, and other indigenous parameters, the effects on metal bioavailability, bioaccessibility, and fraction redistribution in sediment were evaluated. The major mechanisms for sediment treated by Ca(NO3)2 and CaO2 are biostimulation with indigenous denitrifying bacteria and chemical oxidation, respectively. After applying Ca(NO3)2 and CaO2, the decreases of metal concentrations in the treated sediment were insignificant within a 35-day incubation period. However, the [SEMtot-AVS]/f OC increased near to the effective boundary of toxicity (100 μmol g(-1) organic carbon (OC)), indicating that both bioavailability and bioaccessibility of metals (Cu, Zn, and Ni) to benthic organisms are enhanced after remediation. Metals were found redistributed from relatively stable fractions (oxidizable and residual fractions) to weakly bound fractions (exchangeable and reducible fractions), and the results are in line with the enhanced metal bioavailability. Compared with Ca(NO3)2, CaO2 led to higher enhancement in metal bioavailability and bioaccessibility, and more significant metal redistribution, probably due to its stronger chemical reactive capacity to AVS and sediment organic matter. The reactions in CaO2-treated sediment would probably shift from physicochemical to biochemical heterotrophic oxidation for sediment organic matter degradation. Therefore, further investigation on the long-term metal redistribution and associated

  19. Application of humic compounds for remediation of soils contaminated with heavy metals: the benefits and risks

    Science.gov (United States)

    Motuzova, Galina; Barsova, Natalia; Stepanov, Andrey; Kiseleva, Violetta; Kolchanova, Ksenia; Starkova, Irina; Karpukhin, Mikhail

    2015-04-01

    Applicability of humic compound (HC) "Extra" (potassium humate produced from coal) was studied to remediate soils contaminated with copper in model experiments. Field experiments were carried out in 10-litter plastic containers. The upper layer was prepared as a mixture of loam (pH=5.3), sand (pH=7.4) and peat(pH=5.5). It was underlain consequently by loam and gravel. To study water migration we installed lysimeters. The experiment was conducted in 3 variants: 1) control, 2) control+Cu, 3) control+Cu+HC. Copper was applied in the form of dry powder (CuSO4*5H2O) over the upper layer of the soil column in a concentration of copper equaling to 1000 mg/kg. Total concentration of copper was determined by ICP AAS, its free ions was measured with the help of ion-selective electrode. Humic compound was sprayed on the surface in liquid form. The vessels stayed outdoors from July to October 2014 with additional watering in dry periods. Analysis of lysimetric waters obtained from this model field experiment revealed significant impact of pH. Application of the humic compound produces almost 5 times higher content of soluble organic substances than in the variant without it, and in the first portions of lysimetric waters the difference is 20-fold. Generation of extra organic content in soluble form was accompanied by the 2-6 times increase of the water soluble copper yield. However the content of the free copper ions in lysimetric waters in case of addition of the potassium humate was negligible, because almost all copper was bounded with water-soluble organic substances. The copper content in water extract from the top layer of soil in the variant with HC was about 1 mg/l, that was 2 times higher than without HC. The content of water-soluble organic carbon in HC variant was 100 mg/L, and without HC was 10 times lower (10 mg/l). The water extract from soils enriched in HC was passed through a column filled with weakly basic anion exchange resin DEAE (Cl-form), the eluate was

  20. MOVING BEYOND PUMP AND TREAT TOWARD ENHANCED ATTENUATION AND COMBINED REMEDIES T-AREA, SAVANNAH RIVER SITE

    Energy Technology Data Exchange (ETDEWEB)

    Looney, B; Brian Riha, B; Warren Hyde, W; Jay Noonkester, J; Gerald Blount, G

    2008-04-03

    Groundwater beneath T-Area, a former laboratory and semiworks operation at the Department of Energy (DOE) Savannah River Site, is contaminated by chlorinated solvents (cVOCs). Since the contamination was detected in the 1980s, the cVOCs at T-Area have been treated by a combination of soil vapor extraction and groundwater pump and treat. The site has received approval to discontinue the active treatments and implement a full scale test of enhanced attenuation--an engineering and regulatory strategy that has recently been developed by DOE and the Interstate Technology and Regulatory Council. Enhanced attenuation uses active engineering solutions to alter the target site in such a way that the contaminant plume will passively stabilize and shrink and to document that the action will be effective, timely, and sustainable. The paradigm recognizes that attenuation remedies are fundamentally based on a mass balance. Thus, long-term plume dynamics can be altered either by reducing the contaminant loading from the source or by increasing the rate of natural attenuation processes within all, or part of, the plume volume. The combination of technologies that emerged for T-Area included: (1) neat (pure) vegetable oil deployment in the deep vadose zone in the former source area, (2) emulsified vegetable oil deployment within the footprint of the groundwater plume, and (3) identification of attenuation mechanisms and rates for the distal portion of the plume. In the first part, neat oil spreads laterally forming a thin layer on the water table to intercept and reduce future cVOC loading (via partitioning) and reduce oxygen inputs (via biostimulation). In the second and third parts, emulsified oil forms active bioremediation reactor zones within the plume footprint to degrade existing groundwater contamination (via reductive dechlorination) and stimulates long-term attenuation capacity in the distal plume (via cometabolism). For T-Area, the enhanced attenuation development

  1. Remediation of PCB-contaminated soils. Risk analysis of biological in situ processes

    Energy Technology Data Exchange (ETDEWEB)

    Rein, Arno

    2006-12-08

    Biological in situ measures can be efficient and cost effective options for the remediation of contaminated sites. However, the accepted application requires a detailed and reliable analysis of potential impacts. An important objective is to quantify the potential of contaminant degradation and metabolite formation. This thesis addresses a quantitative multimedia risk assessment. Methodologies and tools were developed for this objective and applied to evaluate in situ bioremediation of soils contaminated with polychlorinated biphenyls (PCBs). Soil bacteria in conjunction with plant roots were addressed (rhizoremediation) with a focus on the use of genetically modified microorganisms (GMOs). PCBs are known to be harmful compounds that are ubiquitously distributed in the environment. PCB contaminations in soil and groundwater were identified as important problems. 209 different congeners are sterically possible, but not all are of environmental significance. PCB congeners of concern were evaluated with respect to their potential toxicity, environmental occurrence and mobility. For this objective, congener specific data on the toxicity potential and the frequency in environmental matrices were collected. To quantify the mobility potential, multimedia modelling was performed applying deterministic and probabilistic procedures. 56 PCB congeners of concern were evaluated, and multimedia risk assessments of PCB-contaminated soils should concentrate on this group. Kinetics parameters were specified for degradation experiments with individual PCB congeners in solution and different bacterial strains. These laboratory assays were performed with wild-type Burkholderia sp. strain LB400 and the genetically modified Pseudomonas fluorescens strains F113pcb and F113L::1180. The F113 derivatives demonstrated a good survival ability in willow (Salix sp.) rhizosphere (mesocosm experiments). Therefore, and due to high depletion rates, rhizoremediation with F113L::1180 and willow

  2. Use of Advanced Oxidation and Aerobic Degradation for Remediation of Various Hydrocarbon Contaminates

    Energy Technology Data Exchange (ETDEWEB)

    Paul Fallgren

    2009-03-06

    contaminants. The results from a study with TCE contaminated-clay indicate that electrochemically inducing reductive dechlorination of TCE in a saturated matrix may offer an effective and viable alternative to remediation TCE and other contaminants with potential of being reduced. Another study focused on steel wool oxidation to electrochemically increase population of hydrocarbon-degrading denitrifying bacteria. Significantly larger denitrifying activity was observed in the cathode chamber of a treatment unit setup like an MFC with steel wool as the anode. This enhanced nitrate reduction could be due to direct electron utilization by denitrifying bacteria on the cathode, thereby stimulating microbial denitrification or a combination of electron transfer directly to NO{sub 3}{sup -} and electron transfer to nitrate reducing bacteria, which may serve as a type of bio-catalyst on the cathode for nitrate reduction. Overall, the studies conducted under Task 72 demonstrated different innovative methods to enhance petroleum hydrocarbon degradation and associated contaminants.

  3. Environmental remediation through sequestration of airfall-derived metals contamination by selective revegetation strategies

    Science.gov (United States)

    Sahagian, D.; Peters, S.; Yasko, G.

    2006-12-01

    Industrial activities in the 20th century left a legacy of contaminated air, water, and soils. The relative environmental enlightenment of the 21st century has already led to reductions in pollution sources, and has improved air and surface water quality in many areas. However, the residence time of contaminants in soils can be lengthy, presenting a challenge to 21st century restoration of impacted ecosystems and communities. The present study is centered on the Borough of Palmerton, PA, and a broad region of adjacent communities that were affected by two zinc smelters that operated continuously for more than 80 years, emitting thousands of tons of heavy metals including zinc, cadmium, lead and arsenic. While the air quality has vastly improved since the closure of the zinc smelters, the community remains adversely affected by the ecological damage caused by the pollution. The north face of the Kittatiny ridge was completely denuded of vegetation from the high metals concentrations. The region suffers further due to the ongoing perception of contaminated soils and water, leaving the town and surrounding areas economically depressed. In this study, we are examining the impact of revegetation strategies, particularly those using warm season grasses to determine which species survive and indeed thrive in the metals-contaminated soils. Because of the large areal extent and locally steep slopes in the broad area of concern, removal of metals from the entire region is impractical. It is considered more effective to sequester the metals in the soil so that they do not leach into the rivers, or enter the food web. Vegetation that absorbs and transports the metals throughout its tissues would mobilize these pollutants into the food web as well as make the metals available to reach the river via leaves and other vegetative structures. In this study, we are monitoring the uptake of metals by test grasses and other plants that are colonizing the contaminated area, as well as

  4. Correlation between DNAPL distribution area and dissolved concentration in surfactant enhanced aquifer remediation effluent: a two-dimensional flow cell study

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Bin; Li, Huiying; Du, Xiaoming; Zhong, Lirong; Yang, Bin; Du, Ping; Gu, Qingbao; Li, Fasheng

    2016-02-01

    During the process of surfactant enhanced aquifer remediation (SEAR), free phase dense non-aqueous phase liquid (DNAPL) may be mobilized and spread. The understanding of the impact of DNAPL spreading on the SEAR remediation is not sufficient with its positive effect infrequently mentioned. To evaluate the correlation between DNAPL spreading and remediation efficiency, a two-dimensional sandbox apparatus was used to simulate the migration and dissolution process of 1,2-DCA (1,2-dichloroethane) DNAPL in SEAR. Distribution area of DNAPL in the sandbox was determined by digital image analysis and correlated with effluent DNAPL concentration. The results showed that the effluent DNAPL concentration has significant positive linear correlation with the DNAPL distribution area, indicating the mobilization of DNAPL could improve remediation efficiency by enlarging total NAPL-water interfacial area for mass transfer. Meanwhile, the vertical migration of 1,2-DCA was limited within the boundary of aquifer in all experiments, implying that by manipulating injection parameters in SEAR, optimal remediation efficiency can be reached while the risk of DNAPL vertical migration is minimized. This study provides a convenient visible and quantitative method for the optimization of parameters for SEAR project, and an approach of rapid predicting the extent of DNAPL contaminant distribution based on the dissolved DNAPL concentration in the extraction well.

  5. Correlation between DNAPL distribution area and dissolved concentration in surfactant enhanced aquifer remediation effluent: A two-dimensional flow cell study.

    Science.gov (United States)

    Wu, Bin; Li, Huiying; Du, Xiaoming; Zhong, Lirong; Yang, Bin; Du, Ping; Gu, Qingbao; Li, Fasheng

    2016-02-01

    During the process of surfactant enhanced aquifer remediation (SEAR), free phase dense non-aqueous phase liquid (DNAPL) may be mobilized and spread. The understanding of the impact of DNAPL spreading on the SEAR remediation is not sufficient with its positive effect infrequently mentioned. To evaluate the correlation between DNAPL spreading and remediation efficiency, a two-dimensional sandbox apparatus was used to simulate the migration and dissolution process of 1,2-DCA (1,2-dichloroethane) DNAPL in SEAR. Distribution area of DNAPL in the sandbox was determined by digital image analysis and correlated with effluent DNAPL concentration. The results showed that the effluent DNAPL concentration has significant positive linear correlation with the DNAPL distribution area, indicating the mobilization of DNAPL could improve remediation efficiency by enlarging total NAPL-water interfacial area for mass transfer. Meanwhile, the vertical migration of 1,2-DCA was limited within the boundary of aquifer in all experiments, implying that by manipulating injection parameters in SEAR, optimal remediation efficiency can be reached while the risk of DNAPL vertical migration is minimized. This study provides a convenient visible and quantitative method for the optimization of parameters for SEAR project, and an approach of rapid predicting the extent of DNAPL contaminant distribution based on the dissolved DNAPL concentration in the extraction well.

  6. Quality Assurance Plan for the remedial investigation of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, G.P.; Miller, D.E. [Automated Sciences Group, Inc., Oak Ridge, TN (United States)

    1992-12-01

    The Oak Ridge National Laboratory (ORNL) Waste Area Grouping (WAG) 2 Site Investigation (SI)includes the lower portion of the White Oak Creek (WOC) drainage and enbayment, and associated floodplain and subsurface environment. The ORNL main plant and the major waste storage and disposal facilities at ORNL are located in the WOC watershed and are drained by the WOC system to the Clinch River, located off-site. Environmental media are contaminated and continue to receive contaminants from hydrologically upgradient WAGS. WAG 2 is important as a conduit from upgradient areas to the Clinch River. The general objectives of the WAG 2 SI Project are to conduct a multimedia monitoring and characterization program to define and monitor the input of contaminants from adjacent WAGS, monitor and gather sufficient information for processes controlling or driving contaminant fluxes to construct an appropriate conceptual model for WAG 2, and prepare for the eventual remediation of WAG 2.

  7. Work plan for the remedial investigation/feasibility study for the groundwater operable units at the Chemical Plant Area and the Ordnance Works Area, Weldon Spring, Missouri

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    US Department of Energy (DOE) and the US Army Corps of Engineers (CE) are conducting cleanup activities at two properties, the chemical plant area and the ordnance works area, located adjacent to one another in St. Charles County, Missouri. In accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended, DOE and CE are evaluating conditions and potential responses at the chemical plant area and at the ordnance works area, respectively, to address groundwater and surface water contamination. This work plan provides a comprehensive evaluation of areas that are relevant to the (GWOUs) of both the chemical plant and the ordnance works area. Following areas or media are addressed in this work plan: groundwater beneath the chemical plant area (including designated vicinity properties described in Section 5 of the RI for the chemical plant area [DOE 1992d]) and beneath the ordnance works area; surface water and sediment at selected springs, including Burgermeister Spring. The organization of this work plan is as follows: Chapter 1 discusses the objectives for conducting the evaluation, including a summary of relevant site information and overall environmental compliance activities to be undertaken; Chapter 2 presents a history and a description of the site and areas addressed within the GWOUs, along with currently available data; Chapter 3 presents a preliminary evaluation of areas included in the GWOUs, which is based on information given in Section 2, and discusses data requirements; Chapter 4 presents rationale for data collection or characterization activities to be carried out in the remedial investigation (RI) phase, along with brief summaries of supporting documents ancillary to this work plan; Chapter 5 discusses the activities planned for GWOUs under each of the 14 tasks for an remedial (RI/FS); Chapter 6 presents proposed schedules for RI/FS for the GWOUS; and Chapter 7 explains the project management structure.

  8. On-site and in situ remediation technologies applicable to petroleum hydrocarbon contaminated sites in the Antarctic and Arctic

    Directory of Open Access Journals (Sweden)

    Danielle Camenzuli

    2015-09-01

    Full Text Available Petroleum hydrocarbon contaminated sites, associated with the contemporary and legacy effects of human activities, remain a serious environmental problem in the Antarctic and Arctic. The management of contaminated sites in these regions is often confounded by the logistical, environmental, legislative and financial challenges associated with operating in polar environments. In response to the need for efficient and safe methods for managing contaminated sites, several technologies have been adapted for on-site or in situ application in these regions. This article reviews six technologies which are currently being adapted or developed for the remediation of petroleum hydrocarbon contaminated sites in the Antarctic and Arctic. Bioremediation, landfarming, biopiles, phytoremediation, electrokinetic remediation and permeable reactive barriers are reviewed and discussed with respect to their advantages, limitations and potential for the long-term management of soil and groundwater contaminated with petroleum hydrocarbons in the Antarctic and Arctic. Although these technologies demonstrate potential for application in the Antarctic and Arctic, their effectiveness is dependent on site-specific factors including terrain, soil moisture and temperature, freeze–thaw processes and the indigenous microbial population. The importance of detailed site assessment prior to on-site or in situ implementation is emphasized, and it is argued that coupling of technologies represents one strategy for effective, long-term management of petroleum hydrocarbon contaminated sites in the Antarctic and Arctic.

  9. White Oak Creek Watershed: Melton Valley Area Remedial Investigation Report, Oak Ridge National Laboratory, Oak Ridge, Tennessee: Volume 3 Appendix C

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    This report provides details on the baseline ecological risk assessment conducted in support of the Remedial Investigation (RI) Report for the Melton Valley areas of the White Oak Creek watershed (WOCW). The RI presents an analysis meant to enable the US Department of Energy (DOE) to pursue a series of remedial actions resulting in site cleanup and stabilization. The ecological risk assessment builds off of the WOCW screening ecological risk assessment. All information available for contaminated sites under the jurisdiction of the US Department of Energy`s Comprehensive Environmental Response, Compensation, and Liability Act Federal Facilities Agreement within the White Oak Creek (WOC) RI area has been used to identify areas of potential concern with respect to the presence of contamination posing a potential risk to ecological receptors within the Melton Valley area of the White Oak Creek watershed. The risk assessment report evaluates the potential risks to receptors within each subbasin of the watershed as well as at a watershed-wide scale. The WOC system has been exposed to contaminant releases from Oak Ridge National Laboratory and associated operations since 1943 and continues to receive contaminants from adjacent waste area groupings.

  10. Physical countermeasures to sustain acceptable living and working conditions in radioactively contaminated residential areas

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, K.G.; Roed, J.; Eged, K. [and others

    2003-02-01

    The Chernobyl accident highlighted the need in nuclear preparedness for robust, effective and sustainable countermeasure strategies for restoration of radioactively contaminated residential areas. Under the EC-supporter STRATEGY project a series of investigations were made of countermeasures that were deemed potentially applicable for implementation in such events in European Member States. The findings are presented in this report, in a standardised data sheet format to clarify the features of the individual methods and facilitate intercomparison. The aspects of averted doses and management of wastes generated by countermeasures had to be described separately to provide room for the required level of detail. The information is mainly intended as a tool for decision makers and planners and constitutes of basis for the STRATEGY decision framework for remediation of contaminated urban areas. (au)

  11. Physical countermeasures to sustain acceptable living and working conditions in radioactively contaminated residential areas

    CERN Document Server

    Andersson, K G; Roed, J

    2003-01-01

    The Chernobyl accident highlighted the need in nuclear preparedness for robust, effective and sustainable countermeasure strategies for restoration of radioactively contaminated residential areas. Under the EC-supporter STRATEGY project a series of investigations were made of countermeasures that were deemed potentially applicable for implementation in such events in European Member States. The findings are presented in this report, in a standardised data sheet format to clarify the features of the individual methods and facilitate intercomparison. The aspects of averted doses and management of wastes generated by countermeasures had to be described separately to provide room for the required level of detail. The information is mainly intended as a tool for decision makers and planners and constitutes of basis for the STRATEGY decision framework for remediation of contaminated urban areas. (au)

  12. Mercury pollution in the Chongqing part of the Three Gorges Reservoir area and its remediation and prevention

    Institute of Scientific and Technical Information of China (English)

    YANG Zhen-ning; LIU Xin-an; LU Ting; HUANG Jian-jun

    2008-01-01

    Mercury pollution in the Three Gorges Reservoir area of P. R. China merits special attention. We investigated into the current situation in the Chongqing part of the Reservoir area, identified the pollution sources and proposed some suggestions for the remediation and prevention of mercury pollution in this area. Atmospheric mercury in Chongqing was mainly from coal burning and releases of mercury-containing products such as various types of lights and fever thermometers. Urban drainage in Chongqing and Changshou, and runoffs from the high mercury background area in the lower reaches of the Wujiang River contributed most of the mercury in the water of the Yangtze River. A majority of the blame should be laid on mercury and gold mining in the Wujiang valley. We suggested foresting sloping lands to relieve soil erosion and prevent mercury-bearing soil from running into rivers, educational activities to discourage use of mercury-containing products and improved infrastructure to collect mercury-containing wastes for reducing mercury releases, more facilities for treating wastewater and solid waste to accommodate increased requirements of discharge, and growing selected perennial plants in mercury-contaminated land to absorb the mercury in soil. We also suggested concerted operation of a dedicated water-quality monitoring system, reinforced legislation and an effective administrative mechanism to ensure lasting efforts are invested in curbing mercury releases and restoring mercury contaminated land and water in the Reservoir area.

  13. Potential remediation approach for uranium-contaminated groundwaters through potassium uranyl vanadate precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Tokunaga, T.K.; Kim, Y.; Wan, J.

    2009-06-01

    Methods for remediating groundwaters contaminated with uranium (U) through precipitation under oxidizing conditions are needed because bioreduction-based approaches require indefinite supply of electron donor. Although strategies based on precipitation of some phosphate minerals within the (meta)autunite group have been considered for this purpose, thermodynamic calculations for K- and Ca-uranyl phopsphates, meta-ankoleite and autunite, predict that U concentrations will exceed the Maximum Contaminant Level (MCL = 0.13 {micro}M for U) at any pH and pCO{sub 2}, unless phosphate is maintained at much higher concentrations than the sub-{micro}M levels typically found in groundwaters. We hypothesized that potassium uranyl vanadate will control U(VI) concentrations below regulatory levels in slightly acidic to neutral solutions based on thermodynamic data available for carnotite, K{sub 2}(UO{sub 2}){sub 2}V{sub 2}O8. The calculations indicate that maintaining U concentrations below the MCL through precipitation of carnotite will be sustainable in some oxidizing waters having pH in the range of 5.5 to 7, even when dissolution of this solid phase becomes the sole supply of sub-{micro}M levels of V. Batch experiments were conducted in solutions at pH 6.0 and 7.8, chosen because of their very different predicted extents of U(VI) removal. Conditions were identified where U concentrations dropped below its MCL within 1 to 5 days of contact with oxidizing solutions containing 0.2 to 10 mM K, and 0.1 to 20 {micro}M V(V). This method may also have application in extracting (mining) U and V from groundwaters where they both occur at elevated concentrations.

  14. Waste area Grouping 2 Phase I remedial investigation: Sediment and Cesium-137 transport modeling report

    Energy Technology Data Exchange (ETDEWEB)

    Clapp, R.B.; Bao, Y.S.; Moore, T.D.; Brenkert, A.L.; Purucker, S.T.; Reece, D.K.; Burgoa, B.B.

    1996-06-01

    This report is one of five reports issued in 1996 that provide follow-up information to the Phase I Remedial Investigation (RI) Report for Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL). The five reports address areas of concern that may present immediate risk to public health at the Clinch River and ecological risk within WAG 2 at ORNL. A sixth report, on groundwater, in the series documenting WAG 2 RI Phase I results were part of project activities conducted in FY 1996. The five reports that complete activities conducted as part of Phase I of the Remedial Investigation (RI) for WAG 2 are as follows: (1) Waste Area Grouping 2, Phase I Task Data Report: Seep Data Assessment, (2) Waste Area Grouping 2, Phase I Task Data Report: Tributaries Data Assessment, (3) Waste Area Grouping 2, Phase I Task Data Report: Ecological Risk Assessment, (4) Waste Area Grouping 2, Phase I Task Data Report: Human Health Risk Assessment, (5) Waste Area Grouping 2, Phase I Task Data Report: Sediment and {sup 137}Cs Transport Modeling In December 1990, the Remedial Investigation Plan for Waste Area Grouping 2 at Oak Ridge National Laboratory was issued (ORNL 1990). The WAG 2 RI Plan was structured with a short-term component to be conducted while upgradient WAGs are investigated and remediated, and a long-term component that will complete the RI process for WAG 2 following remediation of upgradient WAGs. RI activities for the short-term component were initiated with the approval of the Environmental Protection Agency, Region IV (EPA), and the Tennessee Department of Environment and Conservation (TDEC). This report presents the results of an investigation of the risk associated with possible future releases of {sup 137}Cs due to an extreme flood. The results are based on field measurements made during storms and computer model simulations.

  15. The Role Of Mineralogy And Geochemistry In The Understanding Of The Trace Elements Soil Pollution And Remediation. Cases Study In Mining Areas Of Andalucia (South Spain).

    Science.gov (United States)

    Romero, Antonio; González, Isabel; Galán, Emilio

    2016-04-01

    Geochemical and mineralogical studies of soils potentially polluted by trace elements are basic to find the source of pollution, to understand the behaviour of the contaminants in the environment and, finally, to propose remediation and reclamation actions. This work reviews the role of the Mineralogy and Geochemistry to assess the hazard of soil contamination, focusing on several studies carried out in the Andalusian Community (South Spain). To assess the degree of contamination, regional and local geochemical baselines should be established in order to distinguish the geogenic from the anthropogenic contribution, particularly in mining areas where both sources overlap. In these areas, mineralogical studies of the primary phases releasing contaminant elements and the secondary phases precipitating will help to understand the processes affecting the contamination. Agricultural activities are also important sources of trace elements into soils. Several examples show they may be relevant even in mining areas. The metals reaching the soil tend to be accumulated, but they can mobilize under certain physical-chemical environments. The hazard of the contamination will depend on the availability of the trace elements, the adsorption processes and the stability of mineral phases storing the trace elements. Several results show that the availability of trace elements is usually higher in contaminated sites than in geogenic soils, regardless the total concentration. Mineralogical and geochemical studies are then interesting to understand the processes affecting the contamination, as well as to prevent the hazard to the population.

  16. Soil-Water Repellency and Critical Humidity as Cleanup Criteria for Remediation of a Hydrocarbon Contaminated Mud

    Science.gov (United States)

    Guzmán, Francisco Javier; Adams, Randy H.

    2010-05-01

    were not experienced. This permitted the development of a complete vegetative cover, vigorous growth, and transformation of a geologic substrate (bentonitic drilling muds) into a soil-like material apt for agricultural use. This focus on soil-water relationships and the use of soil fertility parameters in general is important in establishing cleanup criteria for the real remediation of hydrocarbon contaminated sites in agricultural areas. As seen in this study, relatively high WDPT and MED values may not necessarily indicate soil moisture problems and these need to be complemented with actual site information on soil humidity during the annual cycle and with determinations of critical humidity. Additionally, the augmentation of field capacity using organic conditioners may effectively mitigate potential critical humidity problems.

  17. Implementing heterogeneous catalytic dechlorination technology for remediating TCE-contaminated groundwater.

    Science.gov (United States)

    Davie, Matthew G; Cheng, Hefa; Hopkins, Gary D; Lebron, Carmen A; Reinhard, Martin

    2008-12-01

    To transition catalytic reductive dechlorination (CRD) into practice, it is necessary to demonstrate the effectiveness, robustness, and economic competitiveness of CRD-based treatment systems. A CRD system scaled up from previous laboratory studies was tested for remediating groundwater contaminated with 500-1200 microg L(-1) trichloroethylene (TCE) at Edwards Air Force Base (AFB), California. Groundwater was pumped from a treatment well at 2 gal min(-1), amended with hydrogen to 0.35 mg L(-1) and contacted for 2.3 min with 20 kg eggshell-coated Pd on alumina beads (2% Pd by wt) packed in a fixed-bed reactor, and then returned to the aquifer. Operation was continuous for 23 h followed a 1 h regeneration cycle. After regeneration, TCE removal was 99.8% for 4 to 9 h and then declined to 98.3% due to catalyst deactivation. The observed catalyst deactivation was tentatively attributed to formation of sulfidic compounds; modeling of catalyst deactivation kinetics suggests the presence of sulfidic species equivalent to 2-4 mg L(-1) hydrogen sulfide in the reactor water. Over the more than 100 day demonstration period, TCE concentrations in the treated groundwater were reduced by >99% to an average concentration of 4.1 microg L(-1). The results demonstrate CRD as a viable treatment alternative technically and economically competitive with activated carbon adsorption and other conventional physicochemical treatmenttechnologies.

  18. The use of vetiver for remediation of heavy metal soil contamination.

    Science.gov (United States)

    Antiochia, Riccarda; Campanella, Luigi; Ghezzi, Paola; Movassaghi, K

    2007-06-01

    The use of Vetiveria zizanioides (vetiver) was studied to evaluate its efficiency for the remediation of soils contaminated by heavy metals. Vetiver plants were tested for Cr, Cu, Pb and Zn. Phytoextraction and bioremediation experiments were carried out by irrigating the vetiver plants and the dry plants with solutions containing suitable amounts of Cr, Cu, Pd and Zn. The concentrations of the heavy metals were determined in both experiments in shoot and root parts of vetiver plants using inductively coupled plasma atomic emission spectroscopy after a mineralization step. Phytoextraction experiments showed a poor efficiency of vetiver for Cr and Cu uptake (both less than 0.1% in shoots and roots after 30 days), but a quite high capability of Pb and Zn uptake (0.4% in shoots and 1% in roots for Pb and 1% both in shoots and in roots for Zn, after 30 days). For these reasons the vetiver plant can be considered a quite good "hyperaccumulator" only for Pb and Zn. As for bioremediation experiments, the vetiver plant showed heavy metal uptake values significantly lower than those obtained with other biological substrates.

  19. The use of vetiver for remediation of heavy metal soil contamination

    Energy Technology Data Exchange (ETDEWEB)

    Antiochia, Riccarda [Universita di Padova, Dipartimento di Scienze Chimiche, Padua (Italy); Campanella, Luigi; Ghezzi, Paola [Universita ' ' La Sapienza' ' , Dipartimento di Chimica, Rome (Italy); Movassaghi, K. [University of Isfahan, Department of Chemistry, Isfahan (Iran)

    2007-06-15

    The use of Vetiveria zizanioides (vetiver) was studied to evaluate its efficiency for the remediation of soils contaminated by heavy metals. Vetiver plants were tested for Cr, Cu, Pb and Zn. Phytoextraction and bioremediation experiments were carried out by irrigating the vetiver plants and the dry plants with solutions containing suitable amounts of Cr, Cu, Pd and Zn. The concentrations of the heavy metals were determined in both experiments in shoot and root parts of vetiver plants using inductively coupled plasma atomic emission spectroscopy after a mineralization step. Phytoextraction experiments showed a poor efficiency of vetiver for Cr and Cu uptake (both less than 0.1% in shoots and roots after 30 days), but a quite high capability of Pb and Zn uptake (0.4% in shoots and 1% in roots for Pb and 1% both in shoots and in roots for Zn, after 30 days). For these reasons the vetiver plant can be considered a quite good ''hyperaccumulator'' only for Pb and Zn. As for bioremediation experiments, the vetiver plant showed heavy metal uptake values significantly lower than those obtained with other biological substrates. (orig.)

  20. In situ stabilization remediation of cadmium contaminated soils of wastewater irrigation region using sepiolite

    Institute of Scientific and Technical Information of China (English)

    Yuebing Sun; Guohong Sun; Yingming Xu; Lin Wang; Dasong Lin; Xuefeng Liang; Xin Shi

    2012-01-01

    The effects of immobilization remediation of Cd-contaminated soils using sepiolite on soil pH,enzyme activities and microbial communities,TCLP-Cd (toxicity characteristic leaching procedure-Cd) concentration,and spinach (Spinacia oleracea) growth and Cd uptake and accumulation were investigated.Results showed that the addition of sepiolite could increase soil pH,while the TCLP-Cd concentration in soil was decreased with increasing sepiolite.The changes of soil enzyme activities and bacteria number indicated that a certain metabolic recovery occurred after the sepiolite treatments,and spinach shoot biomass increased by 58.5%-65.5% in comparison with the control group when the concentration of sepiolite was ≤ 10 g/kg.However,the Cd concentrations in the shoots and roots of spinach decreased with an increase in the rate of sepiolite,experiencing 38.4%-59.1% and 12.6%-43.6% reduction,respectively,in contrast to the control.The results indicated that sepiolite has the potential for success on a field scale in reducing Cd entry into the food chain.

  1. Mercury remediation potential of a mercury resistant strain Sphingopyxis sp. SE2 isolated from contaminated soil.

    Science.gov (United States)

    Mahbub, Khandaker Rayhan; Krishnan, Kannan; Naidu, Ravi; Megharaj, Mallavarapu

    2017-01-01

    A mercury resistant bacterial strain SE2 was isolated from contaminated soil. The 16s rRNA gene sequencing confirms the strain as Sphingopyxis belongs to the Sphingomonadaceae family of the α-Proteobacteria group. The isolate showed high resistance to mercury with estimated concentrations of Hg that caused 50% reduction in growth (EC50) of 5.97 and 6.22mg/L and minimum inhibitory concentrations (MICs) of 32.19 and 34.95mg/L in minimal and rich media, respectively. The qualitative detection of volatilized mercury and the presence of mercuric reductase enzyme proved that the strain SE2 can potentially remediate mercury. ICP-QQQ-MS analysis of the remaining mercury in experimental broths indicated that a maximum of 44% mercury was volatilized within 6hr by live SE2 culture. Furthermore a small quantity (23%) of mercury was accumulated in live cell pellets. While no volatilization was caused by dead cells, sorption of mercury was confirmed. The mercuric reductase gene merA was amplified and sequenced. Homology was observed among the amino acid sequences of mercuric reductase enzyme of different organisms from α-Proteobacteria and ascomycota groups.

  2. Contrasting Effects of Farmyard Manure (FYM) and Compost for Remediation of Metal Contaminated Soil.

    Science.gov (United States)

    Sabir, Muhammad; Ali, Amanat; Zia-Ur-rehman, Muhammad; Hakeem, Khalid Rehman

    2015-01-01

    We investigated effect of farm yard manure (FYM) and compost applied to metal contaminated soil at rate of 1% (FYM-1, compost-1), 2% (FYM-2, compost-2), and 3% (FYM-3, compost-3). FYM significantly (P compost increased root dry weight compared to control. Amendments significantly increased nickel (Ni) in shoots and roots of maize except compost applied at 1%. FYM-3 and -1 caused maximum Ni in shoots (11.42 mg kg(-1)) and roots (80.92 mg kg(-1)), respectively while compost-2 caused maximum Ni (14.08 mg kg(-1)) and (163.87 mg kg(-1)) in shoots and roots, respectively. Plants grown in pots amended with FYM-2 and compost-1 contained minimum Cu (30.12 and 30.11 mg kg(-1)) in shoots, respectively. FYM-2 and compost-2 caused minimum zinc (Zn) (59.08 and 66.0 mg kg(-1)) in maize shoots, respectively. FYM-2 caused minimum Mn in maize shoots while compost increased Mn in shoots and roots compared to control. FYM and compost increased the ammonium bicarbonate diethylene triamine penta acetic acid (AB-DTPA) extractable Ni and Mn in the soil and decreased Cu and Zn. Lower remediation factors for all metals with compost indicated that compost was effective to stabilize the metals in soil compared to FYM.

  3. Characterizing toxic Cr(VI) contamination in chromite mine overburden dump and its bacterial remediation.

    Science.gov (United States)

    Dhal, B; Das, N N; Thatoi, H N; Pandey, B D

    2013-09-15

    Cr(VI) generated due to natural oxidation of chromite mineral present in chromite mine overburden (COB) dumps of Sukinda, India, has been characterized by different physico-chemical methods. The Cr(VI) was found to be associated with goethite matrix at a contamination level of 500 mg Cr(VI)kg(-1) of COB. Bacillus sp. isolated from the overburden sample exhibiting high tolerance to the hexavalent chromium, was used for the remediation of Cr(VI) in the overburden. The process was optimized while varying the parameters such as pH (2-9), pulp density (10-60%) and temperature (25-40 °C). Optimal reduction of more than 98% of Cr(VI) in the COB sample was achieved in 16 h at pH∼7.0 and 60% pulp density with the Bacillus sp. (4.05 × 10(7)cells mL(-1)) in absence of media. The exponential rate equation yielded rate constant value of 2.14 × 10(-1)h(-1) at 60% pulp density. The mode of bio-reduction of Cr(VI) in the overburden sample was established by FT-IR, XRD, EPMA and SEM-EDS studies.

  4. Potential of four forage grasses in remediation of Cd and Zn contaminated soils.

    Science.gov (United States)

    Zhang, Xingfeng; Xia, Hanping; Li, Zhian; Zhuang, Ping; Gao, Bo

    2010-03-01

    A pot experiment was conducted in a greenhouse to evaluate the phytoremediation abilities of four forage grasses with respect to soil Cd and Zn pollution. High Cd pollution significantly increased the biomass of Pennisetum americanum (L.) LeekexPennisetum purpureum Schumach, showed no effect on Silphium perfoliatum Linn and significantly decreased biomass of Paspalum atratum cv. Reyan No. 11 and Stylosanthes guianensis cv. Reyan II. High Zn pollution significantly decreased biomass of all grasses. Shoot Cd extraction amounts were 624, 179, 21 and 15mug/plant for P. americanumxP. purpureum, P. atratum, S. guianensis and S. perfoliatum respectively at soil Cd concentration of 8mg/kg. The shoot Zn extraction amount for P. americanumxP. purpureum was 8189mug/plant while the other three grasses were severely intoxicated at the soil Zn concentration of 600mg/kg. P. americanumxP. purpureum and P. atratum could be useful for phytoextraction of either or both Cd and Zn pollution; S. perfoliatum could be regarded as a candidate species for phytostabilization of Cd contamination; while S. guianensis had no remediation capability.

  5. Particulate Pyrite Autotrophic Denitrification (PPAD) for Remediation of Nitrate-contaminated Groundwater

    Science.gov (United States)

    Tong, S.; Rodriguez-Gonzalez, L. C.; Henderson, M.; Feng, C.; Ergas, S. J.

    2015-12-01

    The rapid movement of human civilization towards urbanization, industrialization, and increased agricultural activities has introduced a large amount of nitrate into groundwater. Nitrate is a toxic substance discharged from groundwater to rivers and leads to decreased dissolved oxygen and eutrophication. For this experiment, an electron donor is needed to convert nitrate into non-toxic nitrogen gas. Pyrite is one of the most abundant minerals in the earth's crust making it an ideal candidate as an electron donor. The overall goal of this research was to investigate the potential for pyrite to be utilized as an electron donor for autotrophic denitrification of nitrate-contaminated groundwater. Batch studies of particulate pyrite autotrophic denitrification (PPAD) of synthetic groundwater (100 mg NO3--N L-1) were set up with varying biomass concentration, pyrite dose, and pyrite particle size. Reactors were seeded with mixed liquor volatile suspended solids (VSS) from a biological nitrogen removal wastewater treatment facility. PPAD using small pyrite particles (treatment and promoted the utilization of pyrite in the field of environmental remediation.

  6. CO2 Radiocarbon Analysis to Quantify Organic Contaminant Degradation, MNA, and Engineered Remediation Approaches

    Science.gov (United States)

    2014-12-18

    environmental cleanup in the United States. One must understand the interplay between contaminants and natural compounds in complex biogeochemical ...carbon through natural biogeochemical cycles. Only recently has commercially available accelerator mass spectrometry (AMS) allowed routine 14CO2...Soil gas CO2 was assayed for radiocarbon content and CO2 concentration (Fig. 3). Background wells ( circled area) had a CO2 age from ~15 to 25 pMC. This

  7. Emergency remediation measures of a hydroxyisobutyronitrile spill using hydraulic and hydrochemical barriers and pump and treat system (Rho area-Milan, Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Avanzini, M.; Nespoli, M.; Pagotto, A. [EG Engenireeing Geology, Milano (Italy); Peretta, G.P. [Torino Univ. (Italy). Dipt. di Scienze della Terra

    1998-12-31

    The paper deals about emergency clean-up measures after an accidental contamination by hydroxyisobutyronitrile (acetone cyanohydrin) occurred in a aquifer in the industrial area of ELF-ATOCHEM in Rho (province of Milan). Site investigations and tests carried out for planning barrier wells lay-out, injection wells of hydrogen peroxide and in situ treatment of contaminated soil are illustrated. This combined measures system allowed to obtain a high efficacy in pollutant removal in accordance to the Authority`s requests. The final goal of the remediation system activity was reached fifteen months later: concentrations measured at monitoring wells showed values compatible with standards for drinking water quality.

  8. In situ remediation and phytotoxicity assessment of lead-contaminated soil by biochar-supported nHAP.

    Science.gov (United States)

    Yang, Zhangmei; Fang, Zhanqiang; Tsang, Pokeung Eric; Fang, Jianzhang; Zhao, Dongye

    2016-11-01

    In this study, a kind of biochar-supported nano-hydroxyapatite (nHAP@BC) material was used in in-situ remediation of lead-contaminated soil. Column experiments were performed to compare the mobility of nHAP@BC and Bare-nHAP. The immobilization, accumulation and toxic effects of Pb in the after-amended soil were assessed by the in vitro toxicity tests and pot experiments. The column experiments showed a significant improvement in the mobility of nHAP@BC. The immobilization rate of Pb in the soil was 74.8% after nHAP@BC remediation. Sequential extraction procedures revealed that the residual fraction of Pb increased by 66.6% after nHAP@BC remediation, which greatly reduced the bioavailability of Pb in the soil. In addition, pot experiments indicated that nHAP@BC could effectively reduce the upward translocation capacity of Pb in a soil-plant system. The concentration of Pb in the aerial part of the cabbage mustard was 0.1 mg/kg, which is lower than the tolerance limit (0.3 mg/kg). nHAP@BC can remediate Pb-contaminated soil effectively, which can restore soil quality for planting.

  9. Remediation and reclamation of soils heavily contaminated with toxic metals as a substrate for greening with ornamental plants and grasses.

    Science.gov (United States)

    Jelusic, Masa; Lestan, Domen

    2015-11-01

    Soils highly contaminated with toxic metals are currently treated as waste despite their potential inherent fertility. We applied EDTA washing technology featuring chelant and process water recovery for remediation of soil with 4037, 2527, and 26 mg kg(-1) of Pb, Zn and Cd, respectively in a pilot scale. A high EDTA dose (120 mmol kg(-1) of soil) removed 70%, 15%, and 58% of Pb, Zn, and Cd, respectively, and reduced human oral bioaccessibility of Pb below the limit of quantification and that of Zn and Cd 3.4 and 3.2 times. In a lysimeters experiment, the contaminated and remediated soils were laid into two garden beds (4×1×0.15 m) equipped with lysimeters, and subjected to cultivation of ornamental plants: Impatiens walleriana, Tagetes erecta, Pelargonium×peltatum, and Verbena×hybrida and grasses: Dactylis glomerata, Lolium multiflorum, and Festuca pratensis. Plants grown on remediated soil demonstrated the same or greater biomass yield and reduced the uptake of Pb, Zn and Cd up to 10, 2.5 and 9.5 times, respectively, compared to plants cultivated on the original soil. The results suggest that EDTA remediation produced soil suitable for greening. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Remediation of Cr(VI) contaminated soil using long-duration sodium thiosulfate supported by micro–nano networks

    Energy Technology Data Exchange (ETDEWEB)

    He, Lulu [School of Life Sciences, Anhui Agricultural University, Hefei 230036 (China); Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Wang, Min; Zhang, Guilong [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Qiu, Guannan [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Cai, Dongqing, E-mail: dqcai@ipp.ac.cn [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Wu, Zhengyan, E-mail: zywu@ipp.ac.cn [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Zhang, Xin, E-mail: xinzhang@ahau.edu.cn [School of Life Sciences, Anhui Agricultural University, Hefei 230036 (China)

    2015-08-30

    Highlights: • This work aims to develop a long-duration remediation agent (LRA). • LRA was obtained using Na{sub 2}S{sub 2}O{sub 3} supported by attapulgite (ATP) micro–nano networks. • ATP micro–nano networks was induced by high-energy electron beam irradiation. • LRA can effectively control the migration of Cr(VI) and reducing Cr(VI) to Cr(III). • LRA displayed high performance on the remediation of heavy metal contaminated soil. - Abstract: In this work, a long-duration remediation agent (LRA) on hexavalent chromium (Cr(VI)) was developed using sodium thiosulfate (ST) supported by attapulgite (ATP) micro–nano networks induced through high-energy electron beam (HEEB) irradiation. The ATP networks could effectively reduce the leaching amount of Cr(VI) in soil. More importantly, the ATP networks could significantly control the leaching behavior of ST, and then prolong the duration and increase the reduction efficiency of ST on Cr(VI). As a result, LRA displayed high performance on controlling the migration of Cr(VI) and reducing Cr(VI) to Cr(III). Additionally, pot experiment indicated that LRA could effectively decrease the absorbed amount of Cr(VI) in corn, and reduce the inhibition effect of Cr(VI) on the growth of corn. Therefore, this work could provide a facile approach to remediate the Cr(VI)-contaminated soil and lower the harmful effect of Cr(VI) on crop.

  11. Vertical Extent of 100 Area Vadose Zone Contamination of Metals at the Hanford Site

    Science.gov (United States)

    Khaleel, R.; Mehta, S.

    2012-12-01

    The 100 Area is part of the U.S. Department of Energy Hanford Site in southeastern Washington and borders the Columbia River. The primary sources of contamination in the area are associated with the operation of nine former production reactors, the last one shutting down in 1988. The area is undergoing a CERCLA remedial investigation (RI) that will provide data to support final cleanup decisions. During reactor operations, cooling water contaminated with radioactive and hazardous chemicals was discharged to both the adjacent Columbia River and infiltration cribs and trenches. Contaminated solid wastes were disposed of in burial grounds; the estimated Lead-Cadmium used as "reactor poison" and disposed of in 100 Area burial grounds is 1103 metric tons, of which up to 1059 metric tons are Lead and 44 metric tons are Cadmium. We summarize vadose zone site characterization data for the recently drilled boreholes, including the vertical distribution of concentration profiles for metals (i.e., Lead, Arsenic and Mercury) under the near neutral pH and oxygenated conditions. The deep borehole measurements targeted in the RI work plan were identified with a bias towards locating contaminants throughout the vadose zone and targeted areas at or near the waste sites; i.e., the drilling as well as the sampling was biased towards capturing contamination within the "hot spots." Unlike non-reactive contaminants such as tritium, Arsenic, Mercury and Lead are known to have a higher distribution coefficient (Kd), expected to be relatively immobile, and have a long residence time within the vadose zone. However, a number of sediment samples located close to the water table exceed the background concentrations for Lead and Arsenic. Three conceptual models are postulated to explain the deeper than expected penetration for the metals.

  12. Health and safety plan for the Remedial Investigation and Site Investigation of Waste Area Grouping 2 at the Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Cofer, G.H.; Holt, V.L.; Roupe, G.W.

    1993-11-01

    This health and safety plan (HASP) was developed by the members of the Measurement Applications and Development Group of the Health Science Research Division at the Oak Ridge National Laboratory (ORNL). This plan was prepared to ensure that health and safety related items for the Waste Area Grouping (WAG) 2 Remedial Investigation (RI)/Feasibility Study and Site Investigation projects conform with the requirements of 29 CFR 1910.120 (April 18, 1992). The RI Plan calls for the characterization, monitoring, risk assessment, and identification of remedial needs and alternatives that have been structured and staged with short-term and long-term objectives. In early FY 1992, the WAG 2 RI was integrated with the ORNL Environmental Restoration (ER) Site Investigations program in order to achieve the complimentary objectives of the projects more effectively by providing an integrated basis of support. The combined effort was named the WAG 2 Remedial Investigation and Site Investigations Program (WAG 2 RI&SI). The Site Investigation activities are a series of monitoring efforts and directed investigations that support other ER activities by providing information about (1) watershed hydrogeology; (2) contaminants, pathways, and fluxes for groundwater at ORNL; (3) shallow subsurface areas that can act as secondary sources of contaminants; and (4) biological populations and contaminants in biota, in addition to other support and coordination activities.

  13. Natural Oxidant Demand Variability, Potential Controls, and Implications for in Situ, Oxidation-Based Remediation of Contaminated Groundwater

    Science.gov (United States)

    Dettmer, A.; Cruz, S.; Dungan, B.; Holguin, F. O.; Ulery, A. L.; Hunter, B.; Carroll, K. C.

    2014-12-01

    Naturally occurring reduced species associated with subsurface materials can impose a significant natural oxidant demand (NOD), which is the bulk consumption of oxidants by soil water, minerals, and organic matter. Although injection of oxidants has been used for chemical transformation of organic contaminants, NOD represents a challenge for the in-situ delivery of oxidants as a remediation alternative. Co-injection of complexation agents with oxidants has been proposed to facilitate the delivery of oxidants for in situ chemical oxidation remediation of contaminated groundwater. This study investigates variability of NOD for different oxidants and sediments. The effect of the addition of various complexation agents, including EDTA, tween 80, hydroxypropyl-beta-cyclodextrin (HPCD), humic acid, and four generations of poly(amidoamine) (PAMAM) dendrimers, on the NOD was also examined. NOD was measured for a clay loam (collected from Air Force Plant 44 in Tucson, AZ). Varying amounts of biosolids were mixed with subsamples of the clay loam to create three additional reference soils in order to study the effect of organic matter and other soil characteristics on the NOD. Bench-scale laboratory experiments were conducted to determine the NOD for various oxidants, using the four soils, and replicated with and without various delivery agents. Measured NOD showed variability for each soil and oxidant composition. Additionally, significant differences were observed in NOD with the addition of delivery agents. The results support the elucidation of potential controls over NOD and have implications for in situ, oxidation-based remediation of contaminated groundwater.

  14. Remediation of soil co-contaminated with petroleum and heavy metals by the integration of electrokinetics and biostimulation.

    Science.gov (United States)

    Dong, Zhi-Yong; Huang, Wen-Hui; Xing, Ding-Feng; Zhang, Hong-Feng

    2013-09-15

    Successful remediation of soil co-contaminated with high levels of organics and heavy metals is a challenging task, because that metal pollutants in soil can partially or completely suppress normal heterotrophic microbial activity and thus hamper biodegradation of organics. In this study, the benefits of integrating electrokinetic (EK) remediation with biodegradation for decontaminating soil co-contaminated with crude oil and Pb were evaluated in laboratory-scale experiments lasting for 30 days. The treated soil contained 12,500 mg/kg of total petroleum hydrocarbons (TPH) and 450 mg/kg Pb. The amendments of EDTA and Tween 80, together with a regular refreshing of electrolyte showed the best performance to remediate this contaminated soil. An important function of EDTA-enhanced EK treatment was to eliminate heavy metal toxicity from the soil, thus activating microbial degradation of oil. Although Tween 80 reduced current, it could serve as a second substrate for enhancing microbial growth and biodegradation. It was found that oil biodegradation degree and microbial numbers increased toward the anode and cathode. Microbial metabolism was found to be beneficial to metal release from the soil matrix. Under the optimum conditions, the soil Pb and TPH removal percentages after 30 days of running reached 81.7% and 88.3%, respectively. After treatment, both the residual soil Pb and TPH concentrations met the requirement of the Chinese soil environmental quality standards. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Environmental materials for remediation of soils contaminated with lead and cadmium using maize (Zea mays L.) growth as a bioindicator.

    Science.gov (United States)

    Shi, Yu; Huang, Zhanbin; Liu, Xiujie; Imran, Suheryani; Peng, Licheng; Dai, Rongji; Deng, Yulin

    2016-04-01

    Heavy metal pollution is a severe environmental problem. Remediation of contaminated soils can be accomplished using environmental materials that are low cost and environmentally friendly. We evaluated the individual and combination effects of humic acid (HA), super absorbent polymer (SAP), zeolite (ZE), and fly ash composites (FC) on immobilization of lead (Pb) and cadmium (Cd) in contaminated soils. We also investigated long-term practical approaches for remediation of heavy metal pollution in soil. The biochemical and morphological properties of maize (Zea mays L.) were selected as biomarkers to assess the effects of environmental materials on heavy metal immobilization. The results showed that addition of test materials to soil effectively reduced heavy metal accumulation in maize foliage, improving chlorophyll levels, plant growth, and antioxidant enzyme activity. The test materials reduced heavy metal injury to maize throughout the growth period. A synergistic effect from combinations of different materials on immobilization of Pb and Cd was determined based on the reduction of morphological and biochemical injuries to maize. The combination of zeolite and humic acid was especially effective. Treatment with a combination of HA + SAP + ZE + FC was superior for remediation of soils contaminated with high levels of Pb and Cd.

  16. Network environmental analysis based ecological risk assessment of a naphthalene-contaminated groundwater ecosystem under varying remedial schemes

    Science.gov (United States)

    Wang, Zheng; He, Li; Lu, Hongwei; Ren, Lixia; Xu, Zongda

    2016-12-01

    Many of the existing ecological risk studies for groundwater ecosystems paid little attention to either small-scale regions (e.g., an industrial contamination site) or ignored anthropogenic activities (e.g., site remediation). This study presented a network environmental analysis based ecological risk assessment (ERA) framework to a naphthalene-contaminated groundwater remediation site. In the ERA, four components (vegetation, herbivore, soil micro-organism and carnivore) were selected, which are directly or indirectly exposed to the contaminated groundwater ecosystem. By incorporating both direct and indirect ecosystem interactions, the risk conditions of the whole ecosystem and its components were quantified and illustrated in the case study. Results indicate that despite there being no input risks for herbivores and carnivores, the respective integral risks increase to 0.0492 and 0.0410. For soil micro-organisms, 58.8% of the integral risk comes from the input risk, while the other 41.2% of the integral risk comes from the direct risk. Therefore, the risk flow within the components is a non-negligible risk origination for soil micro-organisms. However, the integral risk for vegetation was similar to the input risk, indicating no direct risk. The integral risk at the 5-year point after remediation was the highest for the four components. This risk then decreased at the 10-year point, and then again increased. Results from the sensitivity analysis also suggest that the proposed framework is robust enough to avoid disturbance by parameter uncertainty.

  17. PROTON GENERATION BY DISSOLUTION OF INTRINSIC OR AUGMENTED ALUMINOSILICATE MINERALS FOR IN SITU CONTAMINANT REMEDIATION BY ZERO-VALENCE-STATE IRON

    Science.gov (United States)

    Metallic, or zero-valence-state, iron is being incorporated into permeable reactive subsurface barriers for remediating a variety of contaminant plume types. The remediation occurs via reductive processes that are associated with surface corrosion of the iron metal. Reaction rate...

  18. PROTON GENERATION BY DISSOLUTION OF INTRINSIC OR AUGMENTED ALUMINOSILICATE MINERALS FOR IN SITU CONTAMINANT REMEDIATION BY ZERO-VALENCE-STATE IRON

    Science.gov (United States)

    Metallic, or zero-valence-state, iron is being incorporated into permeable reactive subsurface barriers for remediating a variety of contaminant plume types. The remediation occurs via reductive processes that are associated with surface corrosion of the iron metal. Reaction rate...

  19. Feasibility Study of the Use of Thiosulfate as Extractant Agent in the Electrokinetic Remediation of a Soil Contaminated by Mercury from Almadén

    DEFF Research Database (Denmark)

    Subires-Muñoz, José Diego; García-Rubio, Ana; Vereda-Alonso, Carlos

    2010-01-01

    Natural soils are rather complex, making the predictability of the behavior of some remediation techniques very complicated. In this paper, the remediation of a Hg contaminated soil close to Almadén using a thiosulfate solution as extractant agent is studied. In addition, the use of the BCR...

  20. Implications of Fe/Pd Bimetallic Nanoparticles Immobilized on Adsorptive Activated Carbon for the Remediation of Groundwater and Sediment Contaminated with PCBs

    Science.gov (United States)

    In order to respond to the current limitations and challenges in remediating groundwater and sediment contaminated with polychlorinated biphenyls (PCBs), we have recently developed a new strategy, integration of the physical adsorption of PCBs with their electrochemical dechlori...

  1. Implications of Fe/Pd Bimetallic Nanoparticles Immobilized on Adsorptive Activated Carbon for the Remediation of Groundwater and Sediment Contaminated with PCBs

    Science.gov (United States)

    In order to respond to the current limitations and challenges in remediating groundwater and sediment contaminated with polychlorinated biphenyls (PCBs), we have recently developed a new strategy, integration of the physical adsorption of PCBs with their electrochemical dechlori...

  2. ELECTROCHEMICAL REMEDIATION OF ARSENIC-CONTAMINATED GROUNDWATER — RESULTS OF PROTOTYPE FIELD TESTS IN BANGLADESH

    Energy Technology Data Exchange (ETDEWEB)

    Kowolik, K; Addy, S.E.A.; Gadgil, A.

    2009-01-01

    According to the World Health Organization (WHO), more than 50 million people in Bangladesh drink arsenic-laden water, making it the largest case of mass poisoning in human history. Many methods of arsenic removal (mostly using chemical adsorbents) have been studied, but most of these are too expensive and impractical to be implemented in poor countries such as Bangladesh. This project investigates ElectroChemical Arsenic Remediation (ECAR) as an affordable means of removing arsenic. Experiments were performed on site in Bangladesh using a prototype termed “sushi”. This device consists of carbon steel sheets that serve as electrodes wrapped into a cylinder, separated by plastic mesh and surrounded by a tube-like container that serves as a holding cell in which the water is treated electrochemically. During the electrochemical process, current is applied to both electrodes causing iron to oxidize to various forms of iron (hydr)oxides. These species bind to arsenic(V) with very high affi nity. ECAR also has the advantage that As(III), the more toxic form of arsenic, oxidizes to As(V) in situ. Only As(V) is known to complex with iron (hydr)oxides. One of the main objectives of this research is to demonstrate the ability of the new prototype to reduce arsenic concentrations in Bangladesh groundwater from >200 ppb to below the WHO limit of 10 ppb. In addition, varying fl ow rate and dosage and the effect on arsenic removal was investigated. Experiments showed that ECAR reduced Bangladeshi water with an initial arsenic concentration as high as 250 ppb to below 10 ppb. ECAR proved to be effective at dosages as high as 810 Coulombs/Liter (C/L) and as low as 386 C/L (current 1 A, voltage 12 V). These results are encouraging and provide great promise that ECAR is an effi cient method in the remediation of arsenic from contaminated groundwater. A preliminary investigation of arsenic removal trends with varying Coulombic dosage, complexation time and fi ltration methods is

  3. Multi-criteria assessment tool for sustainability appraisal of remediation alternatives for a contaminated site

    DEFF Research Database (Denmark)

    Søndergaard, Gitte Lemming; Binning, Philip John; Bondgård, Morten

    2017-01-01

    the sustainability of remediation alternatives by integrating environmental, societal, and economic criteria in the assessment. Materials and methods: The MCA includes five main decision criteria: remedial effect, remediation cost, remediation time, environmental impacts, and societal impacts. The main criteria...... found to be the most sustainable option. This was especially due to the fact that this option obtained a high score in the main categories Effect and Social impacts, which were weighted highest by the stakeholders. Conclusions: The developed MCA method is structured with five main criteria. Effect...... and time are included in addition to the three pillars of sustainability (environment, society, and economy). The remedial effect of remediation is therefore assessed and weighted separately from the main criteria environment. This structure makes interpretation of criteria scores more transparent...

  4. Biochar- and phosphate-induced immobilization of heavy metals in contaminated soil and water: implication on simultaneous remediation of contaminated soil and groundwater.

    Science.gov (United States)

    Liang, Yuan; Cao, Xinde; Zhao, Ling; Arellano, Eduardo

    2014-03-01

    Long-term wastewater irrigation or solid waste disposal has resulted in the heavy metal contamination in both soil and groundwater. It is often separately implemented for remediation of contaminated soil or groundwater at a specific site. The main objective of this study was to demonstrate the hypothesis of simultaneous remediation of both heavy metal contaminated soil and groundwater by integrating the chemical immobilization and pump-and-treat methods. To accomplish the objective, three experiments were conducted, i.e., an incubation experiment was first conducted to determine how dairy-manure-derived biochar and phosphate rock tailing induced immobilization of Cd in the Cd-contaminated soils; second, a batch sorption experiment was carried out to determine whether the pre-amended contaminated soil still had the ability to retain Pb, Zn and Cd from aqueous solution. BCR sequential extraction as well as XRD and SEM analysis were conducted to explore the possible retention mechanism; and last, a laboratory-scale model test was undertaken by leaching the Pb, Zn, and Cd contaminated groundwater through the pre-amended contaminated soils to demonstrate how the heavy metals in both contaminated soil and groundwater were simultaneously retained and immobilized. The incubation experiment showed that the phosphate biochar were effective in immobilizing soil Cd with Cd concentration in TCLP (toxicity characteristics leaching procedure) extract reduced by 19.6 % and 13.7 %, respectively. The batch sorption experiment revealed that the pre-amended soil still had ability to retain Pb, Zn, and Cd from aqueous solution. The phosphate-induced metal retention was mainly due to the metal-phosphate precipitation, while both sorption and precipitation were responsible for the metal stabilization in the biochar amendment. The laboratory-scale test demonstrated that the soil amended with phosphate removed groundwater Pb, Zn, and Cd by 96.4 %, 44.6 %, and 49.2 %, respectively, and the

  5. Low-concentration tailing and subsequent quicklime-enhanced remediation of volatile chlorinated hydrocarbon-contaminated soils by mechanical soil aeration.

    Science.gov (United States)

    Ma, Yan; Du, Xiaoming; Shi, Yi; Xu, Zhu; Fang, Jidun; Li, Zheng; Li, Fasheng

    2015-02-01

    Mechanical soil aeration has long been regarded as an effective ex-situ remediation technique and as suitable for remediation of large-scale sites contaminated by volatile organic compounds (VOCs) at low cost. However, it has been reported that the removal efficiency of VOCs from soil is relatively low in the late stages of remediation, in association with tailing. Tailing may extend the remediation time required; moreover, it typically results in the presence of contaminants residues at levels far exceeding regulations. In this context, the present study aimed to discuss the tailing that occurs during the process of remediation of soils contaminated artificially with volatile chlorinated hydrocarbons (VCHs) and to assess possible quicklime-enhanced removal mechanisms. The results revealed the following conclusions. First, temperature and aeration rate can be important controls on both the timing of appearance of tailing and the levels of residual contaminants. Furthermore, the addition of quicklime to soil during tailing can reduce the residual concentrations rapidly to below the remedial target values required for site remediation. Finally, mechanical soil aeration can be enhanced using quicklime, which can improve the volatilization of VCHs via increasing soil temperature, reducing soil moisture, and enhancing soil permeability. Our findings give a basic understanding to the elimination of the tailing in the application of mechanical soil aeration, particularly for VOCs-contaminated soils.

  6. Cultural and wild plant species as bio indicators and phyto-remedies of PHC contaminated soils in Russia

    Energy Technology Data Exchange (ETDEWEB)

    Breus, I.; Larionova, N.; Semenova, E.; Breus, V. [Kazan State Univ., Dept. of Geography and Geoecology (Russian Federation)

    2005-07-01

    The biological indicators are widely used along with the chemical and physical soil characteristics for the ecological risk assessment for soils during and after anthropogenic impacts. In many cases it often happens that only biological indicators are capable of establishing the physiological activity of contaminant complex in soil and of revealing the critical levels of soil contamination. Bio-testing is often used to determine the toxicity of various environmental objects - soils, waters, sediments and wastes. Firstly bio-testing demands the selection of testable biological organisms adequate to studying objects. The test objects must be representative for a given contaminated ecosystem community which is influenced by toxicants. So one can obtain data adequate to the real situation and also minimise the mistakes during the extrapolation of data obtained in bio-testing. Among bio-testing methods the methods of soil toxicity determination using high plants gained wide distribution. And moreover, if such plants are relatively tolerant to soil contamination and can accumulate sufficient plant biomass, it is possible to expect their phyto-remediation effect, which can be realized by different mechanisms. But the experimental investigations of the plant use for soil remediation in Russia are now still under development. The aims of this work were: i) the determination and selection of informative bio-indicative parameters could be used for evaluation of PHC (petroleum hydrocarbons) - soil contamination levels; ii) the choose of test plants based on these values; and iii) the revelation of the possible phyto-remediation effects in soil contaminated with PHC.In laboratory experiments the phyto-toxicity of soil contaminated with PHC was evaluated in relation to 35 plant species and sorts traditional and non-traditional for Russia and cultivated for fodder green biomass purposes, and also for some wild plant species. The following parameters were determined in the

  7. Viscosity-Modification to Improve Remediation Efficiencies within Heterogeneous Contaminated Groundwater Aquifers: Laboratory and Field-Scale Evaluation

    Science.gov (United States)

    Silva, J. A.; Crimi, M.

    2013-12-01

    A key challenge in in situ groundwater remediation practice is achieving efficient contact between the injected remedial fluid and the target contamination in the presence of subsurface permeability heterogeneities. Even apparently small permeability contrasts can affect the delivery and subsurface distribution of injected remedial fluids, as a result of preferential flows, and reduce treatment effectiveness as a result of bypassing of contaminated media of lower permeability. Viscosity-modification is a technique that can be used to mitigate the effects of permeability heterogeneity and improve the delivery and distribution of remediation fluids during subsurface injection. Viscosity-modification involves increasing the viscosity of the injected fluid, and modifying the fluids rheological character in some cases. The increased viscosity provides a reduced fluid mobility condition within higher permeability media that, in turn, enhances the penetration of fluids into adjacent lower permeability media, improving the overall sweep efficiency within heterogeneous geomedia. Herein, we present the results of laboratory (two-dimensional flow tank) and numerical experiments that were designed to critically evaluate the utility of viscosity-modification for groundwater remediation application. Specifically, we will address the benefits and limitations of the approach and highlight the effect of system variables on the degree sweep efficiency improvement achievable. We also present the results of a recently completed Environmental Security Technology Certification Program (ESTCP) technology validation project in which viscosity-modification was applied to permanganate in situ chemical oxidation. Site selection criteria, implementation design considerations, and the long-term effects of viscosity-modified fluid treatments will be discussed.

  8. Automated Detection of Contaminated Radar Image Pixels in Mountain Areas

    Institute of Scientific and Technical Information of China (English)

    LIU Liping; Qin XU; Pengfei ZHANG; Shun LIU

    2008-01-01

    In mountain areas,radar observations are often contaminated(1)by echoes from high-speed moving vehicles and(2)by point-wise ground clutter under either normal propagation(NP)or anomalous propa-gation(AP)conditions.Level II data are collected from KMTX(Salt Lake City,Utah)radar to analyze these two types of contamination in the mountain area around the Great Salt Lake.Human experts provide the"ground truth"for possible contamination of either type on each individual pixel.Common features are then extracted for contaminated pixels of each type.For example,pixels contaminated by echoes from high-speed moving vehicles are characterized by large radial velocity and spectrum width.Echoes from a moving train tend to have larger velocity and reflectivity but smaller spectrum width than those from moving vehicles on highways.These contaminated pixels are only seen in areas of large terrain gradient(in the radial direction along the radar beam).The same is true for the second type of contamination-point-wise ground clutters.Six quality control(QC)parameters are selected to quantify the extracted features.Histograms are computed for each QC parameter and grouped for contaminated pixels of each type and also for non-contaminated pixels.Based on the computed histograms,a fuzzy logical algorithm is developed for automated detection of contaminated pixels.The algorithm is tested with KMTX radar data under different(clear and rainy)weather conditions.

  9. Clay slurry and engineered soils as containment technologies for remediation of contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    Williams, J.R. [Reclamation Technology, Inc., Athens, GA (United States); Dudka, S.; Miller, W.P. [Univ. of Georgia, Athens, GA (United States); Johnson, D.O. [Argonne National Lab., IL (United States)

    1997-12-31

    Clay Slurry and Engineered Soils are containment technologies for remediation of waste disposal sites where leaching, groundwater plumes and surface runoff of contaminants are serious ecological hazards to adjacent environments. This technology is a patent-pending process which involves the use of conditioned clay materials mixed with sand and water to form a readily pourable suspension, a clay slurry, which is either placed into a trench barrier system or allowed to de-water to create Engineered Soils. The Engineered Soil forms a layer impervious to water and air, therefore by inhibiting both water and oxygen from penetrating through the soil the material. This material can be installed in layers and as a vertical barrier to create a surface barrier containment system. The clay percentage in the clay slurry and Engineered Soils varies depending on site characteristics and desired performance standards. For example Engineered Soils with 1-2% of clay (dry wt.) had a hydraulic conductivity (K) of 10{sup -8} to 10{sup -1} cm/sec. Tests of tailing materials from a kyanite and pyrite mine showed that the clay slurry was effective not only in reducing the permeability of the treated tailings, but also in decreasing their acidity due to the inherent alkalinity of the clay. The untreated tailings had pH values in the range of 2.4 - 3.1; whereas, the effluent from clay and tailings mixtures had pH values in a slightly alkaline range (7.7-7.9). Pug-mills and high volume slurry pumps can be readily adapted for use in constructing and placing caps and creating Engineered Soils. Moreover, material on site or from a local sand supply can be used to create clay slurries and engineered soils. Clay materials used in cap construction are likewise readily available commercially. As a result, the clay slurry system is very cost effective compared to other capping systems, including the commonly used High Density Polyethylene (HDPE) liner systems.

  10. A comparison of physicochemical methods for the remediation of porous medium systems contaminated with tar

    Science.gov (United States)

    Hauswirth, Scott C.; Miller, Cass T.

    2014-10-01

    The remediation of former manufactured gas plant (FMGP) sites contaminated with tar DNAPLs (dense non-aqueous phase liquids) presents a significant challenge. The tars are viscous mixtures of thousands of individual compounds, including known and suspected carcinogens. This work investigates the use of combinations of mobilization, solubilization, and chemical oxidation approaches to remove and degrade tars and tar components in porous medium systems. Column experiments were conducted using several flushing solutions, including an alkaline-polymer (AP) solution containing NaOH and xanthan gum (XG), a surfactant-polymer (SP) solution containing Triton X-100 surfactant (TX100) and XG, an alkaline-surfactant-polymer (ASP) solution containing NaOH, TX100, and XG, and base-activated sodium persulfate both with and without added TX100. The effectiveness of the flushing solutions was assessed based on both removal of polycyclic aromatic hydrocarbon (PAH) mass and on the reduction of dissolved-phase PAH concentrations. SP flushes of 6.6 to 20.9 PV removed over 99% of residual PAH mass and reduced dissolved-phase concentrations by up to two orders of magnitude. ASP flushing efficiently removed 95-96% of residual PAH mass within about 2 PV, and significantly reduced dissolved-phase concentrations of several low molar mass compounds, including naphthalene, acenaphthene, fluorene, and phenanthrene. AP flushing removed a large portion of the residual tar (77%), but was considerably less effective than SP and ASP in terms of the effect on dissolved PAH concentrations. Persulfate was shown to oxidize tar components, primarily those with low molar mass, however, the overall degradation was relatively low (30-50% in columns with low initial tar saturations), and the impact on dissolved-phase concentrations was minimal.

  11. Mountain Lake, Presidio National Park, San Francisco: Paleoenvironment, heavy metal contamination, sedimentary record rescue, remediation, and public outreach

    Science.gov (United States)

    Myrbo, A.; Rodysill, J. R.; Jones, K.; Reidy, L. M.

    2014-12-01

    Sediment cores from Mountain Lake, a small natural lake in Presidio National Park, San Francisco, CA, provide a record of Bay Area environmental change spanning the past 2000 years, and of unusually high heavy metal contamination in the last century (Reidy 2001). In 2013, partial dredging of the lake removed the upper two meters of lake sediment as part of a remediation effort. Prior to dredging, long and short cores spatially covering the lake and representing deep and shallow environments were recovered from the lake to preserve the paleoenvironmental record of one of the only natural lakes on the San Francisco Peninsula. The cores are curated at LacCore and are available for research by the scientific community. Mountain Lake formed in an interdunal depression and was shallow and fluctuating in its first few hundred years. Lake level rise and inundation of a larger area was followed by lowstands under drier conditions around 550-700 and 1300 CE. Nonnative taxa and cultivars appeared at the time of Spanish settlement in the late 18th century, and the lake underwent eutrophication due to livestock pasturing. U.S. Army landscaping introduced trees to the watershed in the late 19th century. The upper ~1m of sediments document unusually high heavy metal contamination, especially for lead and zinc, caused by the construction and heavy use of Highway 1 on the lake shore. Lead levels peak in 1975 and decline towards the surface, reflecting the history of leaded gasoline use in California. Zinc is derived mainly from automobile tires, and follows a pattern similar to that of lead, but continues to increase towards the surface. Ongoing research includes additional radiocarbon dating and detailed lithological analysis to form the basis of lake-level reconstruction and archeological investigations. Because the Presidio archaeological record does not record human habitation in the area until approximately 1300 years before present, the core analysis also has the potential to

  12. Application of chemical oxidation to remediate HCH-contaminated soil under batch and flow through conditions.

    Science.gov (United States)

    Usman, Muhammad; Tascone, Oriane; Rybnikova, Victoria; Faure, Pierre; Hanna, Khalil

    2017-06-01

    This is the first study describing the chemical oxidation of hexachlorocyclohexanes (HCHs) in contaminated soil under water saturated and unsaturated flow through conditions. Soil contaminated with β-HCH (45 mg kg(-1)) and γ-HCH (lindane, 25 mg kg(-1)) was sampled from former lindane waste storage site. Efficiency of following treatments was tested at circumneutral pH: H2O2 alone, H2O2/Fe(II), Na2S2O8 alone, Na2S2O8/Fe(II), and KMnO4. Experimental conditions (oxidant dose, liquid/solid ratio, and soil granulometry) were first optimized in batch experiments. Obtained results revealed that increasing dose of H2O2 improved the oxidation efficiency while in Na2S2O8 system, maximum HCHs were removed at 300 mM. However, oxidation efficiency was slightly improved by Fe(II)-activation. Increasing the solid/liquid ratio decreased HCH removal in soil samples crushed to 500 μm while an opposite trend was observed for 2-mm samples. Dynamic column experiments showed that oxidation efficiency followed the order KMnO4 > Na2S2O8/Fe(II) > Na2S2O8 whatever the flow condition, whereas the removal extent declined at higher flow rate (e.g., ~50% by KMnO4 at 0.5 mL/min as compared to ~30% at 2 mL/min). Both HCH removal and oxidant decomposition extents were found higher in saturated columns than the unsaturated ones. While no significant change in relative abundance of soil mineral constituents was observed before and after chemical oxidation, more than 60% of extractable organic matter was lost after chemical oxidation, thereby underscoring the non-selective behavior of chemical oxidation in soil. Due to the complexity of soil system, chemical oxidation has rarely been reported under flow through conditions, and therefore our findings will have promising implications in developing remediation techniques under dynamic conditions closer to field applications.

  13. Accumulation of heavy metals from contaminated soil to plants and evaluation of soil remediation by vermiculite.

    Science.gov (United States)

    Malandrino, Mery; Abollino, Ornella; Buoso, Sandro; Giacomino, Agnese; La Gioia, Carmela; Mentasti, Edoardo

    2011-01-01

    We evaluated the distribution of 15 metal ions, namely Al, Cd, Cu, Cr, Fe, La, Mn, Ni, Pb, Sc, Ti, V, Y, Zn and Zr, in the soil of a contaminated site in Piedmont (Italy). This area was found to be heavily contaminated with Cu, Cr and Ni. The availability of these metal ions was studied using Tessier's sequential extraction procedure: the fraction of mobile species, which potentially is the most harmful for the environment, was much higher than that normally present in unpolluted soils. This soil was hence used to evaluate the effectiveness of treatment with vermiculite to reduce the availability of the pollutants to two plants, Lactuca sativa and Spinacia oleracea, by pot experiments. The results indicated that the addition of vermiculite significantly reduces the uptake of metal pollutants by plants, confirming the possibility of using this clay in amendment treatments of metal-contaminated soils. The effect of plant growth on metal fractionation in soils was investigated. Finally, the sum of the metal percentages extracted into the first two fractions of Tessier's protocol was found to be suitable in predicting the phytoavailability of most of the pollutants present in the investigated soil.

  14. Screening of contaminants in Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, B.G.; Frank, M.L.; Hoffman, F.O.; Hook, L.A.; Suter, G.W.; Watts, J.A.

    1992-07-01

    Waste Area Grouping 2 (WAG 2) of the Oak Ridge National Laboratory (ORNL) is located in the White Oak Creek Watershed and is composed of White Oak Creek Embayment, White Oak Lake and associated floodplain, and portions of White Oak Creek (WOC) and Melton Branch downstream of ORNL facilities. Contaminants leaving other ORNL WAGs in the WOC watershed pass through WAG 2 before entering the Clinch River. Health and ecological risk screening analyses were conducted on contaminants in WAG 2 to determine which contaminants were of concern and would require immediate consideration for remedial action and which contaminants could be assigned a low priority or further study. For screening purposes, WAG 2 was divided into four geographic reaches: Reach 1, a portion of WOC; Reach 2, Melton Branch; Reach 3, White Oak Lake and the floodplain area to the weirs on WOC and Melton Branch; and Reach 4, the White Oak Creek Embayment, for which an independent screening analysis has been completed. Screening analyses were conducted using data bases compiled from existing data on carcinogenic and noncarcinogenic contaminants, which included organics, inorganics, and radionuclides. Contaminants for which at least one ample had a concentration above the level of detection were placed in a detectable contaminants data base. Those contaminants for which all samples were below the level of detection were placed in a nondetectable contaminants data base.

  15. Fall 1998 200 East area biological vector contamination report

    Energy Technology Data Exchange (ETDEWEB)

    CONNELL, D.J.

    1999-03-17

    The purpose of this report is to document the investigation into the cause of the spread of radioactive contamination in September and October 1998 at the Hanford Site's 200 East Area and its subsequent spread to the City of Richland Landfill; identify the source of the contamination; and present corrective actions. The focus and thrust of managing the incident was based on the need to accomplish the following, listed in order of importance: (1) protect the health and safety of the Site workers and the public; (2) contain and control the spread of contamination; (3) identify the source of contamination and the pathways for its spread; and (4) identify the causal factors enabling the contamination.

  16. Post-remediation biomonitoring of pesticides and other contaminants in marine waters and sediment near the United Heckathorn Superfund Site, Richmond, California

    Energy Technology Data Exchange (ETDEWEB)

    LD Antrim; NP Kohn

    2000-05-26

    Marine sediment remediation at the United Heckathorn Superfund Site was completed in April 1997. Water and mussel tissues were sampled in February 1999 from four stations near Lauritzen Canal in Richmond, California, for Year 2 of post-remediation monitoring of marine areas near the United Heckathorn Site. Dieldrin and dichlorodiphenyl trichloroethane (DDT) were analyzed in water samples, tissue samples from resident mussels, and tissue samples from transplanted mussels deployed for 4 months. Concentrations of dieldrin and total DDT in water and total DDT in tissue were compared with Year 1 of post-remediation monitoring, and with preremediation data from the California State Mussel Watch program (tissues) and the Ecological Risk Assessment for the United Heckathorn Superfund Site (tissues and water). Mussel tissues were also analyzed for polychlorinated biphenyls (PCB), which were detected in sediment samples. Chlorinated pesticide concentrations in water samples were similar to preremediation levels and did not meet remediation goals. Mean dieidrin concentrations in water ranged from 0.62 rig/L to 12.5 ng/L and were higher than the remediation goal (0.14 ng/L) at all stations. Mean total DDT concentrations in water ranged from 14.4 ng/L to 62.3 ng/L and exceeded the remediation goal (0.59 ng/L) at all stations. The highest concentrations of both pesticides were found at the Lauritzen Canal/End station. Despite exceedence of the remediation goals, chlorinated pesticide concentrations in Lauritzen Canal water samples were notably lower in 1999 than in 1998. Tissue samples from biomonitoring organisms (mussels) provide an indication of the longer-term integrated exposure to contaminants in the water column, which overcomes the limitations of grab samples of water. Biomonitoring results indicated that the bioavailability of chlorinated pesticides has been reduced from preremediation levels both in the dredged area and throughout Richmond Harbor. Total DDT and

  17. Remediation in Situ of Hydrocarbons by Combined Treatment in a Contaminated Alluvial Soil due to an Accidental Spill of LNAPL

    Directory of Open Access Journals (Sweden)

    Ettore Trulli

    2016-10-01

    Full Text Available Soil contamination represents an environmental issue which has become extremely important in the last decades due to the diffusion of industrial activities. Accidents during transport of dangerous materials and fuels may cause severe pollution. The present paper describes the criteria of the actions which were operated to remediate the potential risk and observed negative effects on groundwater and soil originating from an accidental spill of diesel fuel from a tank truck. With the aim to evaluate the quality of the involved environmental matrices in the “emergency” phase, in the following “safety” operation and during the remediation action, a specific survey on hydrocarbons, light and heavy, was carried out in the sand deposits soil. Elaboration of collected data allows us to observe the movement of pollutants in the unsaturated soil. The remediation action was finalized to improve the groundwater and soil quality. The former was treated by a so called “pump and treat” system coupled with air sparging. A train of three different technologies was applied to the unsaturated soil in a sequential process: soil vapour extraction, bioventing and enhanced bioremediation. Results showed that the application of sequential remediation treatments allowed us to obtain a state of quality in unsaturated soil and groundwater as required by Italian law.

  18. A weight of evidence approach for assessing remediation of contaminated sediments using food web tissue contamination, biotic condition and DNA damage

    Science.gov (United States)

    The Ottawa River lies in extreme northwest Ohio, flowing into Lake Erie’s western basin at the city of Toledo. The Ottawa River is a component of the Maumee River Area of Concern (AOC) as defined by the International Joint Commission. In 2009-2010 a sediment remediation pro...

  19. Optimizing spatial sampling for multivariate contamination in urban areas

    NARCIS (Netherlands)

    Groenigen, van J.W.; Pieters, G.; Stein, A.

    2000-01-01

    Effectiveness of regular sampling grids to collect multivariate contamination data in urban areas is often strongly reduced by buildings and boundary effects. In addition, earlier observations and knowledge on the history of the area may provide valuable information. This paper extends a simulated a

  20. Remediation of hydrocarbon contaminated soils in the Canadian Arctic with land farms

    Energy Technology Data Exchange (ETDEWEB)

    Paudyn, K.; Poland, J.S.; Rutter, A.; Rowe, R.K. [Queen' s Univ., Kingston, ON (Canada)

    2005-07-01

    Land farming is a process where petroleum contaminated soils are spread out in a layer 0.3-0.5 cm thick. Nutrients are added and the soils are mixed periodically, as both oxygen and water are necessary for aerobic petroleum hydrocarbon degradation. This paper discusses a trial land farm established at Resolution Island, Nunavut. Three truckloads of contaminated soil were excavated from 2 areas and displaced to a previously leveled area. Heavy equipment was used to homogenize the soil and evenly distribute material to each of four test plots, measuring 5 by 5 metres with a depth of 0.3 metres. Rock material was removed manually throughout the lifetime of the farm. Each plot was subjected to a different regime: a control plot with no action except soil collection; daily rototilling; rototilling every 4 days; and rototilling every 4 days with the addition of fertilizer. Plots were re-sampled after 16, 32, 17, 349, and 369 days. Nitrogen and phosphorus were added to the plot in the form of granular agricultural fertilizers. Results in all 4 plots showed a dramatic decrease in contaminant levels with time, possibly because disturbance of the soil in the creation of the land farm created conditions that promoted loss. Levels were calculated using chromatograms of extracted soil samples. For the 3 plots with no fertilizer, levels indicated that no measurable bioremediation was taking place. The addition of fertilizer is low maintenance and economical. However, the fertilized plot was also rototilled, so it is not yet known how important soil aeration is in assisting bioremediation. Laboratory experiments and the construction of a large scale land farm in 2004 should lead to the development of an optimal land farm operation protocol. 4 refs., 2 figs.

  1. Remediation of soil from lead-contaminated kindergartens reduces the amount of lead adhering to children's hands.

    Science.gov (United States)

    Nielsen, Jesper B; Kristiansen, Jesper

    2005-05-01

    Risk related to contaminated soil is based on the oral intake of soil and dust among children. This exposure is a consequence of mouthing behaviour, which exposes children to whatever adheres to their hands or toys. This project compared hand exposure of children to lead following outdoor playground activities before and after an intervention. The intervention consisted of replacement of contaminated top soil from the most intensively used playground areas and coverage of bare soil with wood chips or grass. We included children from three kindergartens: one with very low levels of lead in soil and two kindergartens with an average lead concentrations in soil of 100-200 mg/kg. Measurements of lead in soil 5-7 weeks after interventions in two kindergartens verified that the interventions had effectively reduced the potential exposure to lead from the most intensively used areas of the playgrounds. The average lead concentration in soil after intervention was below 10 mg/kg. We found a good agreement between the average concentration of lead in soil and the amount of lead on the hands of the children. Thus, the exposure marker worked and had the advantage compared to a blood sample, that we could evaluate the effect of the interventions shortly after they were accomplished using a noninvasive method. The amount of lead on the hands measured in one of the two kindergartens after the remediation (0.73 microg) was not significantly different from the control kindergarten (0.58 microg). Children from the second kindergarten still had higher median exposures to lead (1.29 microg), but a large overlap existed with several children having lower amounts of lead on their hands than some children from the control kindergarten. Large variations in the amount of lead on hands were observed. Variations may reflect true differences in concentrations of lead in soil, but may also reflect different behavior and playing patterns. Our study demonstrated, that it was possible in a cost

  2. Review of heavy metal bio-remediation in contaminated freeway facilitated by adsorption

    Science.gov (United States)

    Zheng, Chaocheng

    2017-08-01

    Toxicity around biological systems is a significant issue for environmental health in a long term. Recent biotechnological approaches for bio-remediation of heavy metals in freeway frequently include mineralization, bio-adsorption or even remediation. Thus, adequate restoration in freeway requiring cooperation, integration and assimilation of such biotechnological advances along with traditional and ethical wisdom to unravel the mystery of nature in the emerging field of bio-remediation was reviewed with highlights to better understand problems associated with toxicity of heavy metals and eco-friendly technologies.

  3. Simulation–optimization model for groundwater contamination remediation using meshfree point collocation method and particle swarm optimization

    Indian Academy of Sciences (India)

    Mategaonkar Meenal; T I Eldho

    2012-06-01

    Remediation of the groundwater contamination problem is a tedious, time consuming and expensive process. Pump and treat (PAT) is one of the commonly used techniques for groundwater remediation in which the contaminated groundwater is pumped, treated and put back to the aquifer system or other sources. Developing simulation-optimization (S/O) model proved to be very useful in the design process of an effective PAT system. Simulation models help in predicting the spatial and temporal variation of the contamination plume while optimization models help in minimizing the cost of pumping. Generally, grid or mesh based models such as Finite Difference Method (FDM) or Finite Element Methods (FEM) is used for the groundwater flow and transport simulation. But it is found that grid/mesh generation is a time consuming process. Therefore, recently Meshfree (MFree) based numerical models are developed to avoid this difficulty of meshing and remeshing. MFree Point Collocation Method (PCM) is a simple meshfree method used for the simulation of coupled groundwater flow and contaminant transport. For groundwater optimization problems, even though number of methods such as linear programming, nonlinear programming, etc. are available, evolutionary algorithm based techniques such as genetic algorithm (GA) and particle swarm optimization (PSO) are found to be very effective. In this paper, a simulation model using MFree PCM for confined groundwater flow and transport and a PSO based single objective optimization model are developed and coupled to get an effective S/O model for groundwater remediation using PAT. The S/O model based on PCM and PSO is applied for a polluted hypothetical confined aquifer and its performance is compared with Finite Element Method–Binary Coded Genetic Algorithm (FEM–GA) model. It is found that both the models are in good agreement with each other showing the applicability of the present approach. The PCM–PSO based S/O model is simple and more

  4. Remediation of uranium-contaminated soil using the Segmented Gate System and containerized vat leaching techniques: a cost effectiveness study

    Energy Technology Data Exchange (ETDEWEB)

    Cummings, M.; Booth, S.R.

    1996-09-01

    Because it is difficult to characterize heterogeneously contaminated soils in detail and to excavate such soils precisely using heavy equipment, it is common for large quantities of uncontaminated soil to be removed during excavation of contaminated sites. Until now, volume reduction of radioactively contaminated soil depended upon manual screening and analysis of samples, a costly and impractical approach, particularly with large volumes of heterogeneously contaminated soil. The baseline approach for the remediation of soils containing radioactive waste is excavation, pretreatment, containerization, and disposal at a federally permitted landfill. However, disposal of low-level radioactive waste is expensive and storage capacity is limited. ThermoNuclean`s Segmented Gate System (SGS) removes only the radioactively contaminated soil, in turn greatly reducing the volume of soils that requires disposal. After processing using the SGS, the fraction of contaminated soil is processed using the containerized vat leaching (CVL) system developed at LANL. Uranium is leached out of the soil in solution. The uranium is recovered with an ion exchange resin, leaving only a small volume of liquid low-level waste requiring disposal. The reclaimed soil can be returned to its original location after treatment with CVL.

  5. Features and Remediation technologies of Pollution in Lead - Zinc Mining Areas of China%我国铅锌矿污染特点及修复技术

    Institute of Scientific and Technical Information of China (English)

    梁桂莲; 钱建平; 张力

    2011-01-01

    我国铅锌矿污染的一般特点是:多元素复合污染;污染元素赋存形式复杂;常叠加化学药剂的污染;重金属污染具有隐蔽性、累积性及不可逆性;部分矿山伴生放射性污染等。针对铅锌矿区的不同污染特点,目前常用的污染修复方法有:电动修复法、合磷物质修复法和植物修复法等。电动修复法适宜于低渗透性污染土壤的修复,具有修复时间短、修复彻底、不会引入环境有害物质等优点。含磷物质是一种廉价有效的重金属污染土壤修复剂,可针对土壤重金属污染的实际状况施以不同类型的含磷化合物以降低有效态重金属的含量。超富集植物修复则具有操作技术简单、成本低%The pollution of the lead- zinc mining areas in China is characterized by combined multi - element pollution, complex existing forms of contaminating elements, generally combined with the chemical agents pollution, the concealment, accumulation and irreversibility of heavy metal pollution, accompanying radioactive contamination in some mines, and so on. The com- mon methods of pollution remediation include electrokinetic re mediation; contaminated soil remediation using phosphorus - containing substances and phytoremediation in lead - zinc miningareas. Electrokinetic remediation is suitable for low permeability polluted soil, and has many advantages such as short repairing time, complete effect, without introduction of harmful substances into the environment. Phosphorus - containing substances are cheap and effective agent for the remediation of heavy metal - contaminated soil. Different types of phosphorus compounds can be reduced the content of available heavy metals in soil according to contaminated situation. The remediation of heavy metal - contaminated soil by hyper accumulator plants, is a promising technology, which has the advantages of simple,low cost, less environmental disturbance and being suitable

  6. Optimising the remediation of sites contaminated by the Wismut uranium mining operations using performance and risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Pelz, F.; Jakubick, A.Th.; Kahnt, R. [Wismut GmbH, Chemnitz (Germany)

    2003-07-01

    The cost and risk assessment at Wismut GmbH is performed for optimising the remediation of sites contaminated by uranium mining and milling. An iterative either probabilistic or deterministic 'top-down' model of the remediation project as an integrated system is used. Initially all relevant processes are captured in a rather abstract and simplistic way. In the course of the model development those variables and processes to which results have been shown to be sensitive are described in more detail. This approach is useful for identifying any gaps in the knowledge base that have to be filled in the course of the multi-attributive decision making. The requirement for optimisation, also with respect to socio-economic impacts, is met by including other variables in addition to costs and health risks. (authors)

  7. Comparative Analysis of Soluble Phosphate Amendments for the Remediation of Heavy Metal Contaminants: Effect on Sediment Hydraulic Conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Wellman, Dawn M.; Icenhower, Jonathan P.; Owen, Antionette T.

    2006-07-10

    A series of conventional, saturated column experiments were conducted to evaluate the effect of utilizing in situ phosphate amendments, for subsurface, metal remediation, on sediment hydraulic conductivity. Experiments were conducted under mildly alkaline/calcareous conditions representative of conditions commonly encountered at sites across the arid western United States, which have been used in weapons and fuel production and display significant subsurface contamination. Results indicate the displacement of a single pore volume of either sodium monophosphate or phytic acid amendments causes approximately a 30% decrease in the hydraulic conductivity of the sediment. Long-chain polyphosphate amendments afford no measurable reduction in hydraulic conductivity. These results demonstrate (1) the utility of long-chain polyphosphate amendments for subsurface metal sequestration and (2) the necessity of conducting column experiments to completely evaluate the effects of subsurface remediation.

  8. Guidelines for Posting Soil Contamination Areas

    Energy Technology Data Exchange (ETDEWEB)

    Mcnaughton, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Eisele, William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-01

    All soil guidelines were determined using RESRAD, version 6.1. All offsite guidelines are based on 15 mrem/year. This dose rate is sufficiently low to protect human health and is in accordance with DOE guidance and the proposed EPA 40-CFR-196 regulations for members of the public (never promulgated). For those onsite areas where general employees (non-radiological workers) could have routine access, soil concentrations should be based on a dose rate of 30 mrem/year (approximately one-third of the onsite LANL non-radiological worker dose of 100 mrem/year). In this case, soil concentration guidelines may be obtained by doubling the 15 mrem/year guidelines. Several scenarios were developed to provide maximum flexibility for application of the guidelines. The offsite guidelines were developed using: residential scenarios for both adults and children; a construction worker scenario; a resource user (e.g., a hunter) scenario; a child playing within canyon reaches scenario, a trail using jogger within canyon reaches scenario, and a trail using hiker within canyon reaches scenario. The residential guidelines represent the lowest values from both the adult residential scenario and the child residential scenario.

  9. Conjunctive effect of CMC-zero-valent iron nanoparticles and FYM in the remediation of chromium-contaminated soils

    Science.gov (United States)

    Madhavi, Vemula; Prasad, Tollamadugu Naga Venkata Krishna Vara; Reddy, Balam Ravindra; Reddy, Ambavaram Vijay Bhaskar; Gajulapalle, Madhavi

    2014-04-01

    Chromium is an important industrial metal used in various products and processes but at the same time causing lethal environmental hazards. Remediation of Cr-contaminated soils poses both technological and economic challenges, as conventional methods are often too expensive and difficult to operate. Zero-valent iron particles at nanoscale are proposed to be one of the important reductants of Cr(VI), transforming the same into nontoxic Cr(III). In the present investigation, soils contaminated with Cr(VI) are allowed to react with the various loadings of zero-valent iron nanoparticles (Fe0) for a reaction period of 24 h. Fe0 nanoparticles were synthesized by the reduction of ferrous sulfate in the presence of sodium borohydride and stabilized with carboxy methyl cellulose and were characterized by scanning electron microscopy, energy dispersion spectroscopy, X-ray diffraction, UV-vis spectrophotometer, Fourier transform-infra red spectrophotometer, Raman spectroscopy, dynamic light scattering technique and zeta potential. Further, this work demonstrates the potential utilization of farm yard manure (FYM) and Fe0 nanoparticles in combination and individually for the effective remediation of Cr(VI)-contaminated soils. An increase in the reduction of Cr(VI) from 60 to 80 % was recorded with the increase in the loading of Fe0 nanoparticles from 0.1 to 0.3 mg/100 g individually and in combination with FYM ranging from 50 to 100 mg/100 g soil.

  10. GROWTH PERFORMANCE, BIOMASS AND PHYTOEXTRACTION EFFICIENCY OF ACACIA MANGIUM AND MELALEUCA CAJUPUTI IN REMEDIATING HEAVY METAL CONTAMINATED SOIL

    Directory of Open Access Journals (Sweden)

    Shibli Nik Mohd

    2013-01-01

    Full Text Available Heavy metals are very toxic and soil contaminated with sewage sludge urgently need remediation in order to avoid related health hazards. Phytoremediation is a low cost and reliable technique to remediate heavy metal contamination. However phytoremediation using timber species was rarely reported and its efficiency was questionable. A field study was conducted to examine the efficiency of two timber species namely Acacia mangium and Melaleuca cajuputi in phytoextraction of Zn, Cu and Cd from contaminated soil. Two hundred of A. mangium and M. cajuputi were planted on sewage sludge disposal site and the growth was recorded for 12 months before at the end total biomass of each species was determined. Results show in 12 months, about 72 and 4 t ha-1 of aboveground biomass can be produced by A. mangium and M. cajuputi, respectively. Both species show potential for phytoremediation, however A. mangium is more efficient compared to M. cajuputi where efficiency of A. mangium to remove Zn was 24.4, 6.2 for Cu and 9.5% for Cd. As for M. cajuputi the efficiency was 1.3, 0.3 and 0.14% for Zn, Cu and Cd, respectively. It is projected that A. mangium require 5, 17 and 20 years to remove 79.82 kg ha-1 of Zn, 46.94 kg ha-1 of Cu and 2.33 kg ha-1 of Cd, respectively.

  11. Selective remediation of contaminated sites using a two-level multiphase strategy and geostatistics.

    Science.gov (United States)

    Saito, Hirotaka; Goovaerts, Pierre

    2003-05-01

    Selective soil remediation aims to reduce costs by cleaning only the fraction of an exposure unit (EU) necessary to lower the average concentration below the regulatory threshold. This approach requires a prior stratification of each EU into smaller remediation units (RU) which are then selected according to various criteria. This paper presents a geostatistical framework to account for uncertainties attached to both RU and EU average concentrations in selective remediation. The selection of RUs is based on their impact on the postremediation probability for the EU average concentration to exceed the regulatory threshold, which is assessed using geostatistical stochastic simulation. Application of the technique to a set of 600 dioxin concentrations collected at Piazza Road EPA Superfund site in Missouri shows a substantial decrease in the number of RU remediated compared with single phase remediation. The lower remediation costs achieved by the new strategy are obtained to the detriment of a higher risk of false negatives, yet for this data set this risk remains below the 5% rate set by EPA region 7.

  12. Comparison of biostimulation and bioaugmentation techniques for the remediation of used motor oil contaminated soil

    Directory of Open Access Journals (Sweden)

    Surajudeen Abdulsalam

    2009-06-01

    Full Text Available This study was carried out on the bioremediation of used motor oil contaminated soil artificially contaminated to a pollutant level of 40,000ppm using biostimulation and bioaugmentation remediation techniques for 42 days. Four treatment options were investigated in wooden microcosms: Control (T1, water amended (T2, biostimulation (T3 and hybrid of biostimulation and bioaugmentation (T4. The effectiveness of bioremediation processes were monitored using the total petroleum hydrocarbon removal (TPH and total bacterial count (TBC. T3 had the highest TPH removal rate (69.2±0.05%, followed by T4 (65.2±0.25% and T2 (58.4±0.5%; the control (T1 had the lowest TPH removal rate (43.2±1.5%. TBC revealed that bioremediation actually took place; T4 had the highest maximum bacterial growth of 9.6E+07CFU/g, followed by T3 (7.2E+07CFU/g, T2 (1.7E+05CFU/g and T1 (1.65E+05CFU/g. In addition, T3 had the highest metal removal rate (2.172% and T4 had the lowest metal removal rate (0.203%.O presente estudo trata da biorremediação usandose solo contaminado artificialmente com óleo de motor a um nível de poluente de 40.000 ppm usando técnicas de remediação por bioestimulação e por bioagumentação durante 42 dias. Quatro opções de tratamento foram investigadas no microcosmo de madeira: Controle (T1, água alterada (T2, bioestimulação (T3 e híbrido de bioestimulação e bioaugmentação (T4. A eficácia dos processos de biorremediação foram monitoradas usando a remoção de hidrocarbonetos totais petróleo (TPH e contagem bacteriana total (TBC. T3 teve a maior taxa de remoção de TPH (69,2 ±; 0,05%, seguido por T4 (65,2 ±; 0,25% e T2 (58,4 ±; 0,5%; o controle (T1 apresentou a menor taxa de remoção de TPH (43,2 ±; 1,5%. TBC revelou que a biorremediação efectivamente ocorreu; T4 teve o maior crescimento de bactérias 9,6E+07CFU/g, seguido pelo T3 (7.2E+07CFU/g, T2 (1.7E+05CFU/g e T1 (1.65E+05CFU/g. Além disso, T3 apresentou a maior taxa de

  13. STUDY ON BIODEGRADATION TECHNOLOGY APPLICATION IN BULK IN THE REMEDIATION OF SOILS CONTAMINATED WITH POLYCYCLIC AROMATIC HYDROCARBONS

    Directory of Open Access Journals (Sweden)

    Irina Ramona PECINGINĂ

    2015-05-01

    Full Text Available Biodecontaminare methods are based on biodegradation in the subsurface presence of microorganisms capable of degrading most of carbonaceous organic pollutants and much of inorganic pollutants. Biodegradation in bulk meet that principle biological decontamination several ways. These methods are intended solely for solids, and is often used for on-site remediation of soils contaminated with organic products. Station bioremediation ensure reducing the harmfulness of residues from oil exploitation activities considered hazardous, using a bioremediation process. Bioremediation process will lead to reduction of oil content and thus reducing the hazard of waste.

  14. Geohydrology and contamination at the Michigan Department of Transportation maintenance garage area, Kalamazoo County, Michigan

    Science.gov (United States)

    Lynch, E.A.; Huffman, G.C.

    1996-01-01

    A leaking underground storage tank was removed from the Michigan Department of Transportation maintenance garage area in Kalamazoo County., Mich., in 1985. The tank had been leaking unleaded gasoline. Although a remediation system was operational at the site for several years after the tank was removed, ground-water samples collected from monitoring wells in the area consistently showed high concentrations of benzene, toluene. ethylbenzene, and xylenes--indicators of the presence of gasoline. The U.S. Geological Survey did a study in cooperation with the Michigan Department of Transportation, to define the geology, hydrology, and occurrence of gasoline contamination in the maintenance garage area. The aquifer affected by gasoline contamination is an unconfined glaci'a.l sand and gravel aquifer. The average depth to water in the study area is about 74.7 feet. Water-level fluctuations are small; maximum fluctuation was slightly more than 1 foot during August 1993-August 1994. Hydraulic conductivities based on aquifer-test data collected for the study and estimated by use of the Cooper-Jacob method of solution ranged from 130 to 144 feet per day. Ground water is moving in an east-southeasterly direction at a rate of about I foot per day. Leakage from perforated pipes leading from the underground storage tanks to the pump station was identified as a second source of gasoline contamination to saturated and unsaturated zones. The existence of this previously unknown second source is part of the reason that previous remediation efforts were ineffective. Residual contaminants in the unsaturated zone are expected to continue to move to the water table with recharge, except in a small area covered by asphalt at the land surface. The gasoline plume from the perforated pipe source has merged with that from the leaking underground storage tank, and the combined plume in the saturated zone is estimated to cover an area of 30,000 square feet. The combined plume is in the upper 20

  15. Environmental- and health-risk-induced remediation design for benzene-contaminated groundwater under parameter uncertainty: a case study in Western Canada.

    Science.gov (United States)

    Fan, X; He, L; Lu, H W; Li, J

    2014-09-01

    This study proposes an environmental- and health-risk-induced remediation design approach for benzene-contaminated groundwater. It involves exposure frequency and intake rates that are important but difficult to be exactly quantified as breakthrough point. Flexible health-risk control is considered in the simulation and optimization work. The proposed approach is then applied to a petroleum-contaminated site in western Canada. Different situations about remediation durations, public concerns, and satisfactory degrees are addressed by the approach. The relationship between environmental standards and health-risk limits is analyzed, in association with their effect on remediation costs. Insights of three uncertain factors (i.e. exposure frequency, intake rate and health-risk threshold) for the remediation system are also explored, on a basis of understanding their impacts on health risk as well as their importance order. The case study results show that (1) nature attenuation plays a more important role in long-term remediation scheme than the pump-and-treat system; (2) carcinogenic risks have greater impact on total pumping rates than environmental standards for long-term remediation; (3) intake rates are the second important factor affecting the remediation system's performance, followed by exposure frequency; (4) the 10-year remediation scheme is the most robust choice when environmental and health-risk concerns are not well quantified. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Remediation of (137)Cs contaminated concrete using electrokinetic phenomena and ionic salt washes in nuclear energy contexts.

    Science.gov (United States)

    Parker, Andrew J; Joyce, Malcolm J; Boxall, Colin

    2017-10-15

    This work describes the first known the use of electrokinetic treatments and ionic salt washes to remediate concrete contaminated with (137)Cs. A series of experiments were performed on concrete samples, contaminated with K(+) and (137)Cs, using a bespoke migration cell and an applied electric field (60V potential gradient and current limit of 35mA). Additionally, two samples were treated with an ionic salt wash (≤400molm(-3) of KCl) alongside the electrokinetic treatment. The results show that the combined treatment produces removal efficiencies three times higher (>60%) than the electrokinetic treatment alone and that the decontamination efficiency appears to be proportional to the initial degree of contamination. Furthermore, the decontamination efficiencies are equivalent to previous electrokinetic studies that utilised hazardous chemical enhancement agents demonstrating the potential of the technique for use on nuclear licensed site. The results highlight the relationship between the initial contamination concentration within the concrete and achievable removal efficiency of electrokinetic treatment and other treatments. This information would be useful when selecting the most appropriate decontamination techniques for particular contamination scenarios. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Integrated Electrokinetics-Adsorption Remediation of Saline-Sodic Soils: Effects of Voltage Gradient and Contaminant Concentration on Soil Electrical Conductivity

    OpenAIRE

    Mohammed Hussain Essa; Nuhu Dalhat Mu’azu; Salihu Lukman; Alaadin Bukhari

    2013-01-01

    In this study, an integrated in situ remediation technique which couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic clay soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg), was used in this study to investigate the effects of voltage gradient, initial contaminant c...

  18. In-Situ Radiological Surveys to Address Nuclear Criticality Safety Requirements During Remediation Activities at the Shallow Land Disposal Area, Armstrong County, Pennsylvania - 12268

    Energy Technology Data Exchange (ETDEWEB)

    Norris, Phillip; Mihalo, Mark; Eberlin, John; Lambert, Mike [Cabrera Services (United States); Matthews, Brian [Nuclear Safety Associates (United States)

    2012-07-01

    Cabrera Services Inc. (CABRERA) is the remedial contractor for the Shallow Land Disposal Area (SLDA) Site in Armstrong County Pennsylvania, a United States (US) Army Corps of Engineers - Buffalo District (USACE) contract. The remediation is being completed under the USACE's Formerly Utilized Sites Remedial Action Program (FUSRAP) which was established to identify, investigate, and clean up or control sites previously used by the Atomic Energy Commission (AEC) and its predecessor, the Manhattan Engineer District (MED). As part of the management of the FUSRAP, the USACE is overseeing investigation and remediation of radiological contamination at the SLDA Site in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), 42 US Code (USC), Section 9601 et. seq, as amended and, the National Oil and Hazardous Substance Pollution Contingency Plan (NCP), Title 40 of the Code of Federal Regulations (CFR) Section 300.430(f) (2). The objective of this project is to clean up radioactive waste at SLDA. The radioactive waste contains special nuclear material (SNM), primarily U-235, in 10 burial trenches, Cabrera duties include processing, packaging and transporting the waste to an offsite disposal facility in accordance with the selected remedial alternative as defined in the Final Record of Decision (USACE, 2007). Of particular importance during the remediation is the need to address nuclear criticality safety (NCS) controls for the safe exhumation and management of waste containing fissile materials. The partnership between Cabrera Services, Inc. and Measutronics Corporation led to the development of a valuable survey tool and operating procedure that are essential components of the SLDA Criticality Safety and Material Control and Accountability programs. Using proven existing technologies in the design and manufacture of the Mobile Survey Cart, the continued deployment of the Cart will allow for an efficient and reliable

  19. 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

  20. Pesticide contamination of the Dridji Cotton Plantation area in the ...

    African Journals Online (AJOL)

    Pesticide contamination of the Dridji Cotton Plantation area in the Republic of Bénin. ... and vegetables eventually may not only end up on the crops, but also in soil and surface water. ... Key words: Pesticides, agriculture, humans, risk, food ...

  1. 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 dense network of multilevel samplers (640 samples). The hydraulic gradient and conductivity were determined. Depletion of the contaminant source is described in the companion paper (Fjordbøge et al., 2012). Field data showed four distinct phases for PCE mass discharge: (1) baseline conditions, (2......) initial rapid reduction, (3) temporary increase, and (4) slow long-term reduction. Numerical modeling was utilized to develop a conceptual understanding of the four phases and to identify the governing processes. The initial rapid reduction of mass discharge was a result of the changed hydraulic...

  2. Native fungi as metal remediators: Silver myco-accumulation from metal contaminated waste-rock dumps (Libiola Mine, Italy).

    Science.gov (United States)

    Cecchi, Grazia; Marescotti, Pietro; Di Piazza, Simone; Zotti, Mirca

    2017-03-04

    Metal contamination constitutes a major source of pollution globally. Many recent studies emphasized the need to develop cheap and green technologies for the remediation or reclamation of environmental matrices contaminated by heavy metals. In this context, fungi are versatile organisms that can be exploited for bioremediation activities. In our work, we tested silver (Ag) bioaccumulation capabilities of three microfungal strains (Aspergillus alliaceus Thom & Church, Trichoderma harzianum Rifai, Clonostachys rosea (Link) Schroers, Samuels, Seifert & W. Gams) isolated from a silver polluted site. The aim was to select silver tolerant native strains and test their potential silver uptake. Among the three species tested, T. harzianum was the most efficient strain to tolerate and accumulate silver, showing an uptake capability of 153 mg L(-1) taken at the Ag concentration of 330 mg L(-1). Our study highlights the potential use of native microfungi spontaneously growing in sulphide-rich waste rock dumps, for silver bioaccumulation and bioremediation.

  3. Surfactant-soil interactions during surfactant-amended remediation of contaminated soils by hydrophobic organic compounds: a review.

    Science.gov (United States)

    Laha, Shonali; Tansel, Berrin; Ussawarujikulchai, Achara

    2009-01-01

    Surfactants are amphiphilic molecules that reduce aqueous surface tension and increase the solubility of hydrophobic organic compounds (HOCs). Surfactant-amended remediation of HOC-contaminated soils and aquifers has received significant attention as an effective treatment strategy - similar in concept to using soaps and detergents as washing agents to remove grease from soiled fabrics. The proposed mechanisms involved in surfactant-amended remediation include: lowering of interfacial tension, surfactant solubilization of HOCs, and the phase transfer of HOC from soil-sorbed to pseudo-aqueous phase. However, as with any proposed chemical countermeasures, there is a concern regarding the fate of the added surfactant. This review summarizes the current state of knowledge regarding nonionic micelle-forming surfactant sorption onto soil, and serves as an introduction to research on that topic. Surfactant sorption onto soil appears to increase with increasing surfactant concentration until the onset of micellization. Sorbed-phase surfactant may account for the majority of added surfactant in surfactant-amended remediation applications, and this may result in increased HOC partitioning onto soil until HOC solubilization by micellar phase surfactant successfully competes with increased HOC sorption on surfactant-modified soil. This review provides discussion of equilibrium partitioning theory to account for the distribution of HOCs between soil, aqueous phase, sorbed surfactant, and micellar surfactant phases, as well as recently developed models for surfactant sorption onto soil. HOC partitioning is characterized by apparent soil-water distribution coefficients in the presence of surfactant.

  4. Field sampling and analysis plan for the remedial investigation of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Boston, H.L.; Ashwood, T.L.; Borders, D.M.; Chidambariah, V.; Downing, D.J.; Fontaine, T.A.; Ketelle, R.H.; Lee, S.Y.; Miller, D.E.; Moore, G.K.; Suter, G.W.; Tardiff, M.F.; Watts, J.A.; Wickliff, D.S.

    1992-02-01

    This field sampling and analysis (S & A) plan has been developed as part of the Department of Energy`s (DOE`s) remedial investigation (RI) of Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL) located in Oak Ridge, Tennessee. The S & A plan has been written in support of the remedial investigation (RI) plan for WAG 2 (ORNL 1990). WAG 2 consists of White Oak Creek (WOC) and its tributaries downstream of the ORNL main plant area, White Oak Lake (WOL), White Oak Creek embayment (WOCE) on the Clinch River, and the associated floodplain and subsurface environment (Fig. 1.1). The WOC system is the surface drainage for the major ORNL WAGs and has been exposed to a diversity of contaminants from operations and waste disposal activities in the WOC watershed. WAG 2 acts as a conduit through which hydrologic fluxes carry contaminants from upgradient