These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Characterization and remediation of highly radioactive contaminated soil at Hanford  

SciTech Connect

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

Buckmaster, M.A. [Westinghouse Hanford Co., Richland, WA (United States); Erickson, J.K. [USDOE Richland Operations Office, WA (United States)

1993-09-01

2

Decontamination of radioactive-contaminated soils: Evaluation of chemical extraction/selective dissolution processes  

SciTech Connect

Rust Federal Services, Inc.`s Clemson Technical Center (CTC) has investigated the remediation of several radioactive-contaminated soils, from various DOE-FUSRAP sites, via soil washing/chemical extraction of the radioactive contaminants. The second phase of this work, which is the subject of this presentation, focused on chemical extraction via selective dissolution of radioactive contaminants. In those instances where simple physical separation processes are not practicable, e.g., when there are relatively high proportions of silt and/or clay particles, chemical extraction and the selective dissolution of target contaminants is required. Soil-decontamination processes frequently employ chelating agents which are meant to selectively enhance the dissolution of target contaminants while minimizing the dissolution of benign soil constituents. This paper will present the dissolution kinetics results from the bench-scale soil-decontamination studies.

Diel, B.N.; North, J.R.; Widner, D.G. [Rust-Clemson Technical Center, Anderson, SC (United States)

1995-12-31

3

Proposed methodology for evaluating low-level radioactively-contaminated soil.  

National Technical Information Service (NTIS)

This report was prepared to support the development of residual radioactivity criteria for disposition of contaminated soil locations at the Idaho National Engineering Laboratory (INEL). The criteria is primarily for use in making decisions regarding disp...

D. R. Alexander, G. W. Clarke, R. L. Dickson

1994-01-01

4

Determination Of Screening Level For Soil Radioactive Contamination  

Microsoft Academic Search

At the present, decision about clean-up of Brazilian sites contaminated with radioactive isotopes is addressed on a case-by-case basis, since there is no general guidance or recommendation to support actions in early phases of the problem identification. For chemicals, CETESB - the governmental organization responsible for preventing and controlling environmental pollution in São Paulo State - established quality reference values

Ana Claudia Peres; Goro Hiromoto

2010-01-01

5

Decontamination of radioactively contaminated soil at the Russian Science Center Kurchatov Institute  

Microsoft Academic Search

The main results of startup operations and experimental operation of a facility for decontaminating radioactively contaminated\\u000a soil are presented. The facility was developed on the basis of water-gravity and mechanical separation of soil, making it\\u000a possible to separate the soil into fractions according to grain size and to identify and remove the finely dispersed fraction\\u000a which is characterized by high

V. G. Volkov; Yu. A. Zverkov; O. P. Ivanov; S. M. Koltyshev; S. G. Semenov; V. E. Stepanov; A. D. Shisha

2007-01-01

6

Micro-PIXE evaluation of radioactive cesium transfer in contaminated soil samples  

NASA Astrophysics Data System (ADS)

Micro-PIXE analysis has been performed on two soil samples with high cesium activity concentrations. These soil samples were contaminated by fallout from the accident at Fukushima Daiichi Nuclear Power Plant. One exhibits a radioactive cesium transfer of ˜0.01, and the other shows a radioactive cesium transfer of less than 0.001, even though both samples have high cesium activity concentrations exceeding 10,000 Bq/kg. X-ray spectra and elemental images of the soil samples revealed the presence of chlorine, which can react with cesium to produce an inorganic soluble compound, and phosphorus-containing cesium-capturable organic compounds.

Fujishiro, F.; Ishii, K.; Matsuyama, S.; Arai, H.; Ishizaki, A.; Osada, N.; Sugai, H.; Kusano, K.; Nozawa, Y.; Yamauchi, S.; Karahashi, M.; Oshikawa, S.; Kikuchi, K.; Koshio, S.; Watanabe, K.; Suzuki, Y.

2014-01-01

7

Bioavailability of caesium-137 from chernozem soils with high and low levels of radioactive contamination  

NASA Astrophysics Data System (ADS)

Bioavailability of Cs-137 in "soil-plant" system of radioactively contaminated terrestrial ecosystems is the most important factor in the understanding of ecological situation. There are many factors affecting the features of Cs-137 biogeochemical cycle: period since an accident, type and intensity of radioactive fallout, general properties of landscape and the specifics of soil and plant covers, etc. In order to evaluate the importance of soil contamination level for the process of Cs-137 translocation from soil to plant the research in forest-steppe areas of Russia with similar natural properties, but contrasting high (Tula region) and low (Kursk region) levels of radioactive Chernobyl fallout (about 25 years after accident) was conducted. Soil cover of both sites is presented by chernozems with bulk density 1.1-1.2 g/cm3, 6-7% humus and neutral pH 6.5-7.2; plant cover under investigation consist of dry and wet meadows with bioproductivity 1.6-2.5 kg/m2 and 85-90% of biomass concentrated underground, that is typical for Russian forest-steppe landscapes. At the same time levels of soil regional contamination with Cs-137 differ by an order - 620-710 Bq/kg (210-250 kBq/m2) in Tula region and 30-55 Bq/kg (10-20 kBq/m2) in Kursk region. At a higher level of soil radioactive contamination specific activity of Cs-137 in vegetation of meadows is noticeably increased (103-160 Bq/kg in Tula region versus 12-14 Bq/kg in Kursk region) with correlation coefficient r 0.87. Increasing of Cs-137 in the underground parts of plants plays a decisive role in this process, while the specific radionuclide's activity in the aboveground parts of different sites is almost invariant (and ubiquitously roots contain 2-5 times more Cs-137 than shoots). The values of transfer factors for Cs-137 (the ratio of the specific Cs-137 activities in the plant tissue and in the soil) at various levels of soil radioactive contamination vary within a relatively narrow range 0.1-0.4, that confirms the discrimination in the radionuclide root uptake. And the higher the level of soil contamination, the more pronounced decreasing of Cs-137 transfer factors with correlation coefficient r -0.89. Further, transfer factors of Cs-137 for aboveground parts of meadow vegetation consist of 0.03-0.012 and always are 2-4 times lower than transfer factors for underground parts. This suggests an existence of biological barrier between the roots and shoots and suppression in the translocation of Cs-137s into aboveground parts of plants. Moreover bioavailability of Cs-137 in the sites of wet meadows is, in accordance with the transfer factors values, even a few more then in the sites of dry meadows regardless of the level of soil radioactive contamination. Thus, general parameters of radionuclide's accumulation in vegetation is closely dependent on its supplies in soil. However, the proportion of Cs-137 root uptake isn't determined by the level of soil radioactive contamination, but mostly by the biological features of vegetation. Study was conducted with the support from the Russian Foundation for Basic Research (project no. 14-05-00903).

Paramonova, Tatiana; Shamshurina, Eugenia; Machaeva, Ekaterina; Belyaev, Vladimir

2014-05-01

8

On-site radioactive soil contamination at the Andreeva Bay shore technical base, Northwest Russia.  

PubMed

The radioactive waste (RAW) storage site at Andreeva Bay in the Russian Northwest has experienced radioactive contamination both as a result of activities carried out at the site and due to incidents that have occurred there in the past such as accidental releases of radioactive materials. The site is an interesting case study for decommissioning due to the extremely large amounts of radioactivity present at the site and the conditions under which it is stored; very little has been previously published in the scientific literature about this site. This paper complements the paper describing dose rates at Andreeva Bay which is published in this issue of Journal of Environmental Radioactivity by the same authors. This study presents new data related to the activity concentrations of (137)Cs and (90)Sr in surface soils and measurements of alpha- and beta-particle fluxes taken at different areas around the site. Limited data on 60Co is also presented. The results of the study indicate that the main areas of site contamination are associated with the former spent nuclear fuel storage facility at Building 5, due to accidental discharges which began in 1982. Substantial contamination is also observed at the solid radioactive waste storage facilities, probably due to the ingress of water into these facilities. More than 240 samples were measured: maximum contamination levels were 1 x 10(6)Bq/kg (137)Cs (mean value 4.1 x 10(5)Bq/kg) and 4 x 10(6)Bq/kg (90)Sr (mean value 1.2 x1 0(5)Bq/kg). Localised patches of alpha and beta contamination were also observed throughout the site. PMID:18276046

Reistad, O; Dowdall, M; Selnaes, Ø G; Standring, W J F; Hustveit, S; Steenhuisen, F; Sørlie, A

2008-07-01

9

Speciation of Radioactive Soil Particles in the Fukushima Contaminated Area by IP Autoradiography and Microanalyses.  

PubMed

Radioactive soil particles several tens of micrometers in size were collected from litter soil in the radiation contaminated area by the Fukushima nuclear plant accident and characterized using electron and X-ray microanalyses. The radioactive particles were discriminated by autoradiography using imaging plates (IP) on which microgrids were formed by laser ablation in order to find the particles under microscopy. Fifty radioactive particles were identified and classified into three types from their morphology and chemical composition, namely: (1) aggregates of clay minerals, (2) organic matter containing clay mineral particulates, and (3) weathered biotite originating from local granite. With respect to the second type, dissolution of the organic matter did not reduce the radiation, suggesting that the radionuclides were also fixed by the clay minerals. The weathered biotite grains have a plate-like shape with well-developed cleavages inside the grains, and kaolin group minerals and goethite filling the cleavage spaces. The reduction of the radiation intensity was measured before and after the trimming of the plate edges using a focused ion beam (FIB), to examine whether radioactive cesium primarily sorbed at frayed edges. The radiation was attenuated in proportion to the volume decrease by the edge trimming, implying that radioactive cesium was sorbed uniformly in the porous weathered biotite. PMID:25343443

Mukai, Hiroki; Hatta, Tamao; Kitazawa, Hideaki; Yamada, Hirohisa; Yaita, Tsuyoshi; Kogure, Toshihiro

2014-11-18

10

Application of in-situ gamma spectrometry in the remediation of radioactively contaminated soil  

SciTech Connect

The Fernald Environmental Management Project (FEMP) is a US Department of Energy site that is undergoing total remediation and closure. Most of the remediation effort entails massive excavation of soil for disposal, both offsite and onsite, at an engineered disposal facility. In-situ gamma spectrometry is routinely used to support soil excavation operations to accurately and quickly identify soil areas as being above or below regulatory remediation criteria. Two different in-situ gamma spectrometry systems are used. The first is a sodium iodide (NaI) detector mounted either on a tractor or a jogging stroller, depending on the terrain to be measured. The NaI system allows the collection of a gamma energy spectrum which can be analyzed to identify and quantify radioactive isotopes which are present within the detector`s viewing area. Each energy spectrum is tagged by location coordinates provided by an on-board global positioning system (GPS) to precisely locate elevated contamination areas. The second is a tripod-mounted, high purity germanium detector (HPGe) gamma spectrometry system that is functionally similar to the NaI system. The principal advantage of the HPGe is its superior resolution, which allows much more accurate identification and quantification of radionuclide contaminants in soils. In order to effectively utilize the data quality objective process with these systems, three quality assurance (QA) elements had to be performed.

Sutton, C.; Yesso, J.D.; Danahy, R.J.; Cox, T.

1999-06-01

11

Lateral migration of Caesium-137 as a heterogeneity factor of soil radioactive contamination within small catchments  

NASA Astrophysics Data System (ADS)

Caesium-137 is long-lived artificial radionuclide with half-life of about 30.17 years. Due to Chernobyl accident in 1986 were received 270-280 PBq of 137Cs. The radioactive material is spread in different directions and then fell to the vast territory on the earth's surface as part of rainfall and under the influence of gravity. The deposition of 137Cs was very heterogeneous due to significant impact of changing weather conditions during the accident. Fixing 137Cs in the soil is because of the high content in the upper layer of fine fractions (especially clay) and organic substances that increase the sorption properties of soil. As a result of small vertical migration down the soil profile, the main migration processes of 137Cs is lateral migration which may occur in soil particles under the deflation but mainly water erosion.The aim of this study was to analyze the main factors of changing the current radioecological situation of small catchments in Chernozem zone of European Russia. The 1st small catchment with total area 1.98 km2 is located in the Kursk Region, where 137Cs soil inventories currently does not exceed 37 kBq/m2. The 2nd small catchment with total area 0.99 km2 is located in the Tula Region called "Plavsk Cs deposition hotspot" was highly contaminated with radioactive fallout with levels up to 600 kBq/m2.For reconstruction of 137Cs initial fallout was defined 4 references sites in Kursk Region and 5 sites in Tula Region. All reference sites were located at the flat interfluve areas in or nearby the study catchment. The analysis of 137Cs inventory within 1st study site references did not show significant differences between them which indicates the absence of the initial fallout heterogeneity. The mean values of 137Cs inventory is 8,7±0,5 kBq/m2 and Cv varies in a range of 13-22%, which are typical for the faraway from Chernobyl territory. Based on 4 references was created the map of initial Chernobyl fallout using the formula of radioactive decay. The next step was creation map of 137Cs contamination of soils using data from slopes and bottoms and its comparison with the map of initial Chernobyl fallout. Subsequently, the 137Cs inventory of soil on slopes and watersheds decreased due to the processes of radioactive decay and removal 137Cs with soil erosion but increased on foot of the slopes and bottoms as a result of accumulation processes. In the bottom of catchment formed zones with 2 times excess of the 137Cs initial fallout which is associated with concentrating runoff of soil material from large areas to the bottom, which occupies about 1 % of the total catchment area.The 137Cs inventory within 2nd study site references varies in a range of 82-211 kBq/m2. There is notable spatial trend on the map of initial fallout have been determined in submeridional direction but no trend in sublatitudinal direction. In 2013 the 137Cs inventories within small catchment bottom also in 1.5-2 times higher than the inventories within watershed. Soil erosion significantly changes composition of 137Cs contaminaition in catchment within no polluted area and no changes within heavily polluted area because of heterogeneous deposition.

Shamshurina, Evgeniya

2014-05-01

12

An improved SOIL*EX{trademark} process for the removal of hazardous and radioactive contaminants from soils, sludges and other materials  

SciTech Connect

Rust`s patented SOIL*EX process is designed to remove hazardous and radioactive contaminants from soils, sludges and a matrix of other materials while destroying volatile organic compounds often associated with contaminated soil and debris. The process is comprised of three major process operations. The first operation involves the dissolution of contaminants that are chemically or mechanically bonded to the solid phase. The second process operation involves separation of the solid phase from the dissolution solution (mother liquor), which contains the dissolved contaminants. The final operation concentrates and removes the contaminants from the mother liquor. A pilot-scale SOIL*EX system was constructed at Rust`s Clemson Technical Center for a Proof-of-Process demonstration. The demonstration program included the design, fabrication, and operation of pilot scale and demonstration equipment and systems. The pilot plant, an accurate scaled-down version of a proposed full-scale treatment system, was operated for five months to demonstrate the efficiency of the overall process. The pilot plant test program focused on demonstrating that the SOIL*EX process would remove and concentrate the contaminants and destroy volatile organic compounds. The pilot plant processed nearly 20 tons of soils and sludges, and test results indicated that all contaminants of concern were removed. Additionally, Rust completed numerous bench scale tests to optimize the chemistry. This paper discusses the pilot plant test criteria and results along with the salient design features of the SOIL*EX system and planned improvements.

Bloom, R.R.; Bonnema, B.E.; Navratil, J.D. [Rust Federal Services, Inc., Golden, CO (United States); Falconer, K.L.; Van Vliet, J.A. [Lockheed Idaho Technology Co., Idaho Falls, ID (United States); Diel, B.N. [Rust Federal Services, Inc., Anderson, SC (United States)

1995-12-31

13

EMERGING TECHNOLOGY SUMMARY: VITRIFICATION OF SOILS CONTAMINATED BY HAZARDOUS AND/OR RADIOACTIVE WASTES  

EPA Science Inventory

A performance summary of an advanced multifuel-capable combustion and melting system (CMS) for the vitrification of hazardous wastes is presented. Vortex Corporation has evaluated its patented CMS for use in the remediation of soils contaminated with heavy metals and radionuclid...

14

Research into the factors affecting the uptake of 90Sr and 137Cs by plants from radioactively contaminated soils of the southern Urals.  

PubMed

The objective of this work was to study the factors affecting the intake of 90Sr and 137Cs by plants from soils exposed to radioactive contamination resulting from operations of the Mayak Industrial Association. Specific activities of 90Sr and 137Cs in the samples were determined by the radiochemical method. The most severe contamination by 90Sr and 137Cs of natural soils was found in forest soil cover and in the 0-5 cm soil layer. The contamination density of the area is mainly determined by activity in the soil layer 0-20 cm that contains 3-97% of 90Sr and 60-92% of 137Cs. Portions of radionuclides contained in soil (89-96% of 90Sr and 18-73% of 137Cs) can be converted into cationic use. An insignificant share of water-soluble radionuclides goes from soil to agricultural produce. PMID:22647915

Kazachonok, Nina N; Kostyuchenko, Vladimir A; Popova, Irina Y; Polyanchikova, Galina V

2012-07-01

15

In situ vitrification: Immobilizing radioactive contaminants in place by melting soils into man-made rocks  

SciTech Connect

From 1951 to 1966 over 1 [times] 10[sup 6] Ci of Cs-137, Sr-90, and other radioisotopes in liquid wastes were disposed of in shallow seepage pits at ORNL. In situ methods to stabilize these sites are being investigated because of radiation exposure risks to personnel during excavation and removal activities. A field test at ORNL of In Situ Vitrification (ISV) was performed to evaluate its ability to resistance heating through graphite electrodes to melt contaminated soils in place. The resulting small lava lake cools and solidifies to a rock consisting of glassy and crystalline material. Volatile products released from the surface of the melt are collected and treated. The Sr-90 was incorporated into mineral phases and residual glass that form upon solidification. The Cs-137, however, is incompatible with the mineral structures and is concentrated into the small amount of residual glass that is trapped in the interstices between mineral grains. Leach tests were performed on samples of sludge, sludge + soil, crushed ISV rock, crushed ISV rock + soil, and low surface area fragments of ISV rock. First, sequential extractions with 0.1 N CaCl[sub 2] were used. Then, sequential treatments with 0.1 N HCl were used. Approximately 10% of the Sr-90 was released from the sludge, with or without soil, after CaCl[sub 2] was applied. Subsequent treatment with HCl released essentially all the Sr-90. The Sr-90 in the crushed ISV rock was resistant to cation exchange, with only 0.4% leached after treatment with CaCl[sub 2]. Treatment with HCl released only 4% of the total Sr-90 present in the crushed ISV rock. The low surface area fragments, more representative of expected field conditions, released 10 [times] less of the Sr-90 than the crushed ISV rock samples. The Cs-137 was not significantly leached from any of the samples of sludge or ISV rock.

Jacobs, G.K.; Spalding, B.P. (Oak Ridge National Lab., TN (United States)); Tixier, J.S. (Pacific Northwest Lab., Richland, WA (United States))

1992-01-01

16

Dynamics of radiostrontium leaching from radioactively contaminated floodplain soils of the Yenisei River  

Microsoft Academic Search

Gleyzation-mediated leaching of radiostrontium from floodplain soils of the Krasnoyarsk Mining and Chemical Combine (MCC)\\u000a activity zone [Atamanovskii Island (front part), Oseredysh Island (front part), and Berezovyi Island (rear part)] is studied\\u000a with model systems. Leaching of radiostrontium from waterlogged soils is analyzed in terms of the model of anaerobic biosolubilization\\u000a of gel films. The leaching of radiostrontium is found

E. K. Legin; Yu. I. Trifonov; M. L. Khokhlov; D. N. Suglobov; E. E. Legina; V. K. Legin

2008-01-01

17

Environmental Geochemistry of Radioactive Contamination  

Microsoft Academic Search

Psychometric studies of public perception of risk have shown that dangers associated with radioactive contamination are considered the most dreaded and among the least understood hazards (Slovic, 1987). Fear of the risks associated with nuclear power and associated contamination has had important effects on policy and commercial decisions in the last few decades. In the US, no new nuclear power

M. D. Siegel; C. R. Bryan

2003-01-01

18

Review of soil contamination guidance  

SciTech Connect

A review of existing and proposed radioactive soil contamination standards and guidance was conducted for United Nuclear Corporation (UNC), Office of Surplus Facilities Management. Information was obtained from both government agencies and other sources during a literature survey. The more applicable standards were reviewed, evaluated, and summarized. Information pertaining to soil contamination for both facility operation and facility decommissioning was obtained from a variety of sources. These sources included: the Code of Federal Regulations, regulatory guides, the Federal Register, topical reports written by various government agencies, topical reports written by national laboratories, and publications from the American National Standards Institute (ANSI). It was difficult to directly compare the standards and guidance obtained from these sources since each was intended for a specific situation and different units or bases were used. However, most of the information reviewed was consistent with the philosophy of maintaining exposures at levels as low as reasonably achievable (ALARA).

Mueller, M.A.; Kennedy, W.E. Jr.; Soldat, J.K.

1981-08-01

19

Environmental Geochemistry of Radioactive Contamination  

NASA Astrophysics Data System (ADS)

Psychometric studies of public perception of risk have shown that dangers associated with radioactive contamination are considered the most dreaded and among the least understood hazards (Slovic, 1987). Fear of the risks associated with nuclear power and associated contamination has had important effects on policy and commercial decisions in the last few decades. In the US, no new nuclear power plants were ordered between 1978 and 2002, even though it has been suggested that the use of nuclear power has led to significantly reduced CO2 emissions and may provide some relief from the potential climatic changes associated with fossil fuel use. The costs of the remediation of sites contaminated by radioactive materials and the projected costs of waste disposal of radioactive waste in the US dwarf many other environmental programs. The cost of disposal of spent nuclear fuel at the proposed repository at Yucca Mountain will likely exceed 10 billion. The estimated total life cycle cost for remediation of US Department of Energy (DOE) weapons production sites ranged from 203-247 billion dollars in constant 1999 dollars, making the cleanup the largest environmental project on the planet (US DOE, 2001). Estimates for the cleanup of the Hanford site alone exceeded $85 billion through 2046 in some of the remediation plans.Policy decisions concerning radioactive contamination should be based on an understanding of the potential migration of radionuclides through the geosphere. In many cases, this potential may have been overestimated, leading to decisions to clean up contaminated sites unnecessarily and exposing workers to unnecessary risk. It is important for both the general public and the scientific community to be familiar with information that is well established, to identify the areas of uncertainty and to understand the significance of that uncertainty to the assessment of risk.

Siegel, M. D.; Bryan, C. R.

2003-12-01

20

Assessing inhalation exposure from airborne soil contaminants  

SciTech Connect

A method of estimation of inhalation exposure to airborne soil contaminants is presented. this method is derived from studies of airborne soil particles with radioactive tags. The concentration of contaminants in air (g/m{sup 3}) can be derived from the product of M, the suspended respirable dust mass concentration (g/m{sup 3}), S, the concentration of contaminant in the soil (g/g), and E{sub f}, an enhancement factor. Typical measurement methods and values of M, and E{sub f} are given along with highlights of experiences with this method.

Shinn, J.H.

1998-04-01

21

Contaminated soil stabilization demonstration  

SciTech Connect

Long-term herbicide control along with a shotcrete cover was constructed at the Hanford Site in May 1991. The cover system allows for maintenance-free containment of contaminants by preventing wind and water transport of contaminants from the soil surface, preventing plant uptake of contaminants, and minimizing water infiltration through the soil column. The cover is composed of two parts: a commercial nonwoven geotextile material impregnated with trifluralin, and a >5-centimeter top cover of shotcrete containing polyethylene fibers. The herbicide-impregnated geotextile functions to prevent plant root growth into contaminated soil if any holes or cracks develop in the shotcrete layer. The herbicide component, trifluralin, is mixed into polymer nodules that degrade slowly over many years, thus releasing trifluralin slowly over time. The shotcrete topcover was sprayed using a sludge pump and air compressor to form a hard, impenetrable surface that prevents wind erosion and reduces water infiltration through the contaminated materials underneath. The benefits of the cover system are expected to last 20 to 30 years. 2 refs., 4 figs.

Kemp, C.J.; Sackschewsky, M.R.; Sampson, A.E.; Phillips, S.J.

1991-10-01

22

New Regulations for Radiation Protection for Work Involving Radioactive Fallout Emitted by the TEPCO Fukushima Daiichi APP Accident-Disposal of Contaminated Soil and Wastes.  

PubMed

The accident at the Fukushima Daiichi Atomic Power Plant that accompanied the Great East Japan Earthquake on March 11, 2011, released a large amount of radioactive material. To rehabilitate the contaminated areas, the government of Japan decided to carry out decontamination work and manage the waste resulting from decontamination. In the summer of 2013, the Ministry of the Environment planned to begin a full-scale process for waste disposal of contaminated soil and wastes removed as part of the decontamination work. The existing regulations were not developed to address such a large amount of contaminated wastes. The Ministry of Health, Labour and Welfare (MHLW), therefore, had to amend the existing regulations for waste disposal workers. The amendment of the general regulation targeted the areas where the existing exposure situation overlaps the planned exposure situation. The MHLW established the demarcation lines between the two regulations to be applied in each situation. The amendment was also intended to establish provisions for the operation of waste disposal facilities that handle large amounts of contaminated materials. Deliberation concerning the regulation was conducted when the facilities were under design; hence, necessary adjustments should be made as needed during the operation of the facilities. PMID:24856781

Yasui, Shojiro

2014-10-01

23

49 CFR 175.705 - Radioactive contamination.  

...2014-10-01 2014-10-01 false Radioactive contamination. 175.705 Section...Classification of Material § 175.705 Radioactive contamination. (a) A carrier...contact by any person with Class 7 (radioactive) materials that may have been...

2014-10-01

24

Surface Contamination Surface contamination from radioactive isotopes is a source of background in the Borex-  

E-print Network

Chapter 5 Surface Contamination Surface contamination from radioactive isotopes is a source contamination is primarily a problem because the radioactive contaminants can be trans- ferred from the surfaces detector components that come in contact with the scintillator. Preventing radioactive contamination

25

Fractal and Topological Complexity of Radioactive Contamination.  

National Technical Information Service (NTIS)

There is verified the hypothesis about multifractal nature of radioactive contamination due to nuclear explosions on Semipalatinsk test site (STS) in Kazakhstan. The fields of terrestrial contamination have extreme high variability caused by a number of n...

N. G. Makarenko, L. M. Karimova, A. G. Terekhov, M. M. Novak

2000-01-01

26

Status of outdoor radioactive contamination at the Hanford Site  

SciTech Connect

This document summarizes the status of outdoor radioactive contamination near Hanford Site facilities and disposal sites. It defines the nature and areal extend of the radioactively contaminated areas and describes the historical, ongoing, and planned radiological monitoring and control activities. Radioactive waste has been disposed of to the soil column since shortly after the reactors and production facilities began operating. Radioactive liquid wastes were placed directly into the ground via liquid discharges to cribs, ponds, ditches, and reverse wells. Solid wastes were placed in trenches, burial vaults, and caissons. Although the Hanford Site covers 1,450 km{sup 2}, the radioactively contaminated area is only about 36 km{sup 2} or 2.5% of the original site. Over time, contamination has migrated from some of the waste management sites through various vectors (e.g., burrowing animals, deep-rooted vegetation, erosion, containment system failure) or has been deposited to the surface soil via spills and unplanned releases (e.g., line leaks/breaks, tank leaks, and stack discharges) and created areas of outdoor radioactivity both on and below the surface. Currently 26 km{sup 2} are posted as surface contamination and 10 km{sup 2} are posted as underground contamination.

McKinney, S.M.; Markes, B.M.

1994-12-01

27

Radiocesium fallout in the grasslands on Sakhalin, Kunashir and Shikotan Islands due to Fukushima accident: the radioactive contamination of soil and plants in 2011.  

PubMed

The accident at the Fukushima Dai-ichi Nuclear Power Plant has resulted in radioactive contamination of environmental media and food in the Far East of Russia, particularly in the Sakhalin Region. To obtain the knowledge about the (134)Cs and (137)Cs spatial distribution in the Sakhalin Region, soil samples were collected at 31 representative grassland sites on Sakhalin, Kunashir and Shikotan islands (43.80°-46.40° N and 142.73°-146.84° E) in the middle of May and around the end of September to early October 2011. In the autumn, vegetation samples (mixed grass/forb crop and bamboo, Sasa sp.) were collected together with soil samples. Maximum measured activity concentrations (on dry weight) of (134)Cs and (137)Cs in soil were 30 Bq kg(-1) and 210 Bq kg(-1), respectively. Within soil profile, (134)Cs activity concentrations declined rapidly with depth. Although for both sampling occasions (in the spring and autumn) the radionuclide was completely retained in the upper 3-4 cm of soil, a deeper penetration of the contaminant into the ground was observed in the autumn. In contrast with (134)Cs, activity concentrations of (137)Cs demonstrated a broad range of the vertical distribution in soil; at most sites, the radionuclide was found down to a depth of 20 cm. This resulted from interfering the aged pre-accidental (137)Cs and the new Fukushima-borne (137)Cs. To calculate contribution of these sources to the inventory of (137)Cs, the (134)Cs:(137)Cs activity ratio of 1:1 in Fukushima fallout (the reference date 15 March 2011) was used. The maximum deposition density of Fukushima-derived (137)Cs was found on Shikotan and Kunashir Islands with average density of 0.124 ± 0.018 kBq m(-2) and 0.086 ± 0.026 kBq m(-2), respectively. Sakhalin Island was less contaminated by Fukushima-derived (137)Cs of 0.021 ± 0.018 kBq m(-2). For the south of Sakhalin Island, the reference inventory of pre-Fukushima (137)Cs was calculated as 1.93 ± 0.25 kBq m(-2) (reference date 15 March 2011). For Shikotan and Kunashir Islands, the pre-Fukushima reference levels of (137)Cs ground contamination appeared to be higher: on average, 2.81 ± 0.35 kBq m(-2). Maximum measured activity concentrations (on wet weight) of (134)Cs and (137)Cs in the vegetation were 5 Bq kg(-1) and 18 Bq kg(-1), respectively. Soil-to-plant aggregated transfer factors, T(ag)s, for (134)Cs were more than an order of magnitude higher than those for (137)Cs. For the above-ground biomass density of 1 kg per m(2) (wet weight), plant contamination may contribute approximately 2% and 0.1% to the ground deposition of Fukushima-derived and pre-accidental (137)Cs, respectively. PMID:23344426

Ramzaev, V; Barkovsky, A; Goncharova, Yu; Gromov, A; Kaduka, M; Romanovich, I

2013-04-01

28

ASSESSMENT OF RADIOACTIVE AND NON-RADIOACTIVE CONTAMINANTS FOUND IN LOW LEVEL RADIOACTIVE WASTE STREAMS  

Microsoft Academic Search

This paper describes and presents the findings from two studies undertaken for the European Commission to assess the long-term impact upon the environment and human health of non-radioactive contaminants found in various low level radioactive waste streams. The initial study investigated the application of safety assessment approaches developed for radioactive contaminants to the assessment of nonradioactive contaminants in low level

R. H. Little; P. R. Maul; J. S. S. Penfoldag

2003-01-01

29

Soil contamination standards for protection of personnel  

SciTech Connect

The objective of this report is to recommend soil contamination levels that will ensure that radionuclide intakes by unprotected workers are likely to give internal doses below selected dose limits during the working year. The three internal dose limits are 1, 100, and 500 mrem per year. In addition, photon, beta, and alpha instrument readings are estimated for these soil concentration limits. Two exposure pathways are considered: the first is inhalation of resuspended dust and the second is ingestion of trace amounts of soil. In addition, radioactive decay and ingrowth of progeny during the year of exposure is included. External dose from the soil contamination is not included because monitoring and control of external exposures is carried out independently from internal exposures, which are the focus of this report. The methods used are similar to those used by Carbaugh and Bihl (1993) to set bioassay criteria for such workers.

Rittmann, P.D.

1998-04-16

30

Radioactivity concentration in soil in Jeddah area, Saudi Arabia  

Microsoft Academic Search

The level of radioactivity in soil was measured in Jeddah area. Cs concentration was determined as an indication of the degree of contamination from Chernobyl accident. Natural uranium and thorium radioactive series, as well as K concentration levels have been determined. These radioisotopes contribute to the background exposure both indoor and outdoor. The concentration of Bi a member of U

Waleed Abulfaraj

1992-01-01

31

Perspectives of Radioactive Contamination in Nuclear War  

PubMed Central

The degrees of risk associated with the medical, industrial and military employment of nuclear energy are compared. The nature of radioactive contamination of areas and of persons resulting from the explosion of nuclear weapons, particularly the relationship between the radiation exposure and the amount of physical debris, is examined. Some theoretical examples are compared quantitatively. It is concluded that the amount of radio-activity that may be carried on the contaminated person involves a minor health hazard from gamma radiation, compared to the irradiation arising from contaminated areas. PMID:6015741

Waters, W. R.

1967-01-01

32

Leachate tests with sewage sludge contaminated by radioactive cesium.  

PubMed

The sewer systems of eastern Japan have transported radioactive fallout from the Fukushima Dai-ichi nuclear power plant accident to wastewater treatment plants, where the radioisotopes have accumulated. To better understand the potential problems associated with the disposal of contaminated sewage sludge in landfills, leachate tests were conducted with radioactive incinerator ash, cement solidification incinerator ash, and dewatered sludge cake. Radioactivity was undetectable in the eluate from incinerator ash and dewatered sludge cake, but about 30% of the radioactivity initially in cement solidification incinerator ash appeared in the eluate during the leaching experiments. Moreover, modification of test conditions revealed that the presence of Ca(2+) ions and strong alkali in the water that contacted the incinerator ash enhanced leaching of cesium. Lastly, the capacity of pit soil to absorb radioactive cesium was estimated to be at least 3.0 Bq/g (dry). PMID:23947711

Tsushima, Ikuo; Ogoshi, Masashi; Harada, Ichiro

2013-01-01

33

Tracer-level radioactive pilot-scale test of in situ vitrification for the stabilization of contaminated soil sites at ORNL  

SciTech Connect

A field demonstration of in situ vitrification (ISV) was completed in May 1991, and produced approximately 12 Mg of melted earthen materials containing 12.7 mCi of radioactivity within 500 g of sludge in amodel of an old seepage trench waste disposal unit. Past waste disposal operations at Oak Ridge National Laboratory have left several contaminated seepage sites. In planning for remediation of such sites, ISV technology has been identified as a leading candidate because of the high risks associated with any retrieval option and because of the usual high quality of vitreous waste form. Major isotopes placed in the test trench were [sup 137]Cs and [sup 90]Sr, with lesser amounts of [sup 6O]Co, [sup 241]Am, and [sup 239,240]Pu. A total of 29 MWh of electrical power was delivered to the ground over a 5-day period producing a melt depth of 8.5 ft. During melting, 2.4% of the [sup 137]Cs volatilized from the melt into an off-gas containment hood and was captured quantitatively on a high efficiency particulate air filter. No volatilization of [sup 90]Sr, [sup 241]Am, or [sup 239,240]Pu was detected and > 99.993% retention of these isotopes in the melt was estimated. The use of added rare earth tracers (Ce, La, and Nd), as surrogates for transuranic isotopes, led to estimated melt retentions of >99.9995% during the test. The molten material, composed of the native soil and dolomitic limestone used for filling the test trench, reached a processing temperature of 1500[degrees]C. Standardized leaching procedures using Product Consistency Testing indicated that the ISV product has excellent characteristics relative to other vitreous nuclear waste forms.

Spalding, B.P.; Jacobs, G.K.; Naney, M.T. (Oak Ridge National Lab., TN (United States)); Dunbar, N.W. (New Mexico Bureau of Mines and Mineral Resources, Socorro, NM (United States)); Tixier, J.S.; Powell, T.D. (Pacific Northwest Lab., Richland, WA (United States))

1992-11-01

34

Tracer-level radioactive pilot-scale test of in situ vitrification for the stabilization of contaminated soil sites at ORNL  

SciTech Connect

A field demonstration of in situ vitrification (ISV) was completed in May 1991, and produced approximately 12 Mg of melted earthen materials containing 12.7 mCi of radioactivity within 500 g of sludge in amodel of an old seepage trench waste disposal unit. Past waste disposal operations at Oak Ridge National Laboratory have left several contaminated seepage sites. In planning for remediation of such sites, ISV technology has been identified as a leading candidate because of the high risks associated with any retrieval option and because of the usual high quality of vitreous waste form. Major isotopes placed in the test trench were {sup 137}Cs and {sup 90}Sr, with lesser amounts of {sup 6O}Co, {sup 241}Am, and {sup 239,240}Pu. A total of 29 MWh of electrical power was delivered to the ground over a 5-day period producing a melt depth of 8.5 ft. During melting, 2.4% of the {sup 137}Cs volatilized from the melt into an off-gas containment hood and was captured quantitatively on a high efficiency particulate air filter. No volatilization of {sup 90}Sr, {sup 241}Am, or {sup 239,240}Pu was detected and > 99.993% retention of these isotopes in the melt was estimated. The use of added rare earth tracers (Ce, La, and Nd), as surrogates for transuranic isotopes, led to estimated melt retentions of >99.9995% during the test. The molten material, composed of the native soil and dolomitic limestone used for filling the test trench, reached a processing temperature of 1500{degrees}C. Standardized leaching procedures using Product Consistency Testing indicated that the ISV product has excellent characteristics relative to other vitreous nuclear waste forms.

Spalding, B.P.; Jacobs, G.K.; Naney, M.T. [Oak Ridge National Lab., TN (United States); Dunbar, N.W. [New Mexico Bureau of Mines and Mineral Resources, Socorro, NM (United States); Tixier, J.S.; Powell, T.D. [Pacific Northwest Lab., Richland, WA (United States)

1992-11-01

35

Recycling radioactively contaminated materials: Experience and prognosis  

SciTech Connect

In recent years, federal agencies, especially the U.S. Department of Energy (DOE), the U.S. Department of Defense (DOD), the U.S. Environmental Protection Agency, and the U.S. Nuclear Regulatory Commission (NRC), as well as the commercial nuclear enterprise, have begun to consider certain radioactively contaminated materials as resources for beneficial reuse rather than wastes. Most outstanding among these materials is metal that has become radioactively contaminated in various activities of the nuclear enterprise. The DOE began to move in the early 1970s to manage contaminated scrap metals as a potential resource rather than a waste. In the mid-1980s, Oak Ridge Operations Office (ORO) initiated moves to involve private industry in responding to DOE needs in dealing with scrap metal. As a result of this action, three firms showed positive moves toward the beneficial reuse of radioactively contaminated scrap metal, both surface and volumetrically contaminated. From among these industrial firms, one was selected to deal with the specified ORO scrap metal inventories and has, at its own expense, developed technologies and constructed processing facilities to deal with large masses of radioactively contaminated metals from any source.

Large, D.E.; Arrowsmith, H.W. (SEG Inc., Oak Ridge, TN (United States))

1993-01-01

36

ASSESSMENT OF RADIOACTIVE AND NON-RADIOACTIVE CONTAMINANTS FOUND IN LOW LEVEL RADIOACTIVE WASTE STREAMS  

SciTech Connect

This paper describes and presents the findings from two studies undertaken for the European Commission to assess the long-term impact upon the environment and human health of non-radioactive contaminants found in various low level radioactive waste streams. The initial study investigated the application of safety assessment approaches developed for radioactive contaminants to the assessment of nonradioactive contaminants in low level radioactive waste. It demonstrated how disposal limits could be derived for a range of non-radioactive contaminants and generic disposal facilities. The follow-up study used the same approach but undertook more detailed, disposal system specific calculations, assessing the impacts of both the non-radioactive and radioactive contaminants. The calculations undertaken indicated that it is prudent to consider non-radioactive, as well as radioactive contaminants, when assessing the impacts of low level radioactive waste disposal. For some waste streams with relatively low concentrations of radionuclides, the potential post-closure disposal impacts from non-radioactive contaminants can be comparable with the potential radiological impacts. For such waste streams there is therefore an added incentive to explore options for recycling the materials involved wherever possible.

R.H. Little, P.R. Maul, J.S.S. Penfoldag

2003-02-27

37

Soils: man-caused radioactivity and radiation forecast  

SciTech Connect

Available in abstract form only. Full text of publication follows: One of the main tasks of the radiation safety guarantee is non-admission of the excess over critical radiation levels. In Russia they are man-caused radiation levels. Meanwhile any radiation measurement represents total radioactivity. That is why it is hard to assess natural and man-caused contributions to total radioactivity. It is shown that soil radioactivity depends on natural factors including radioactivity of rocks and cosmic radiation as well as man-caused factors including nuclear and non-nuclear technologies. Whole totality of these factors includes unpredictable (non-deterministic) factors - nuclear explosions and radiation accidents, and predictable ones (deterministic) - all the rest. Deterministic factors represent background radioactivity whose trends is the base of the radiation forecast. Non-deterministic factors represent man-caused radiation treatment contribution which is to be controlled. This contribution is equal to the difference in measured radioactivity and radiation background. The way of calculation of background radioactivity is proposed. Contemporary soils are complicated technologically influenced systems with multi-leveled spatial and temporary inhomogeneity of radionuclides distribution. Generally analysis area can be characterized by any set of factors of soil radioactivity including natural and man-caused factors. Natural factors are cosmic radiation and radioactivity of rocks. Man-caused factors are shown on Fig. 1. It is obvious that man-caused radioactivity is due to both artificial and natural emitters. Any result of radiation measurement represents total radioactivity i.e. the sum of activities resulting from natural and man-caused emitters. There is no gauge which could separately measure natural and man-caused radioactivity. That is why it is so hard to assess natural and man-caused contributions to soil radioactivity. It would have been possible if human activity had led to contamination of soil only by artificial radionuclides. But we can view a totality of soil radioactivity factors in the following way. (author)

Gablin, Vassily [Scientific-Industrial Association 'Radon', 7th Rostovsky Lane, Moscow 119121 (Russian Federation)

2007-07-01

38

Bioremediating herbicide-contaminated soils.  

PubMed

Combinations of landfarming and biostimulation were evaluated for remediating pesticide wastes. Various amounts of soil contaminated with alachlor and trifluralin (> or = 100 mg/kg each) and metolachlor and atrazine (> or = 20 mg/kg each) were applied to field plots, and sewage sludge or corn meal was incorporated into designated plots. Plots were also treated with fresh spray mixtures in amounts similar to those applied as contaminated soil. Soil bioactivity and dissipation of parent herbicides were monitored after the treatments. During 100 d, soil dehydrogenase activities were highest in organic-material-amended plots. During the same period, the levels of alachlor had declined by 85-95% in amended, contaminated soil-treated plots and by 75-85% in corresponding unamended plots. In freshly sprayed plots, 95-100% of the initial doses of alachlor had dissipated in amended plots, and 85-95% was lost in corresponding unamended plots. The levels of trifluralin had declined by 70-80% in corn-meal-amended plots and by 60-75% in unamended plots. There were no significant differences between dissipation of trifluralin applied as contaminated soil or fresh sprays. PMID:8323266

Dzantor, E K; Felsot, A S; Beck, M J

1993-01-01

39

TRANSPORT OF LOW-LEVEL RADIOACTIVE SOIL AT DEEP-OCEAN DISPOSAL SITE  

EPA Science Inventory

Transport studies were conducted to assess ocean disposal of soil contaminated with low-level natural radioisotopes. he experimental approach involved characterization of the soil for parameters affecting transport and fate of radionuclides- Radioactivity was associated with disc...

40

Natural radioactivity in Spanish soils  

SciTech Connect

The program of studies and surveys of natural radiation and radioactivity in Spain organized by our research group at the end of the 1980s included a 4-y national survey to determine the concentrations of natural radionuclides in soil. Results obtained from measurements of soil samples collected nationwide at >900 sampling sites are reported and discussed in this paper. Correlations between absorbed dose rates in air calculated from natural radionuclide concentrations in soil and terrestrial gamma dose rates measured experimentally outdoors are shown for the different autonomous regions of Spain. Assessment is also made of the dose to the Spanish population from outdoor exposure to terrestrial gamma rays. 26 refs., 5 figs., 2 tabs.

Quindos, L.S.; Fernandez, P.L.; Soto, J. [Univ. of Cantabria, Santander (Spain)] [and others

1994-02-01

41

Radioactive Contamination of Danish Territory  

E-print Network

contamination of Danish territory in the event of a core-melt accident at the Barseback nuclear power plant OF DANISH TERRITORY AFTER CORE-MELT ACCIDENTS AT THE BARSEBACK POWER PLANT by H.L. Giorup, N.O. Jensen, P at the Barseback Power Plant H. L. Gjørup, N. O. Jensen, P. Hedemann Jensen, L. Kristensen, O. J. Nielsen, E. L

42

BIOREMEDIATION OF CONTAMINATED SURFACE SOILS  

EPA Science Inventory

Biological remediation of soils contaminated with organic chemicals is an alternative treatment technology that can often meet the goal of achieving a permanent clean-up remedy at hazardous waste sites, as encouraged by the U.S. Environmental Protection Agency (U.S. EPA) for impl...

43

10 CFR 39.69 - Radioactive contamination control.  

Code of Federal Regulations, 2012 CFR

... Energy 1 2012-01-01 2012-01-01 false Radioactive contamination control. 39.69 Section 39.69 Energy...WELL LOGGING Radiation Safety Requirements § 39.69 Radioactive contamination control. (a) If the licensee...

2012-01-01

44

10 CFR 39.69 - Radioactive contamination control.  

Code of Federal Regulations, 2013 CFR

... Energy 1 2013-01-01 2013-01-01 false Radioactive contamination control. 39.69 Section 39.69 Energy...WELL LOGGING Radiation Safety Requirements § 39.69 Radioactive contamination control. (a) If the licensee...

2013-01-01

45

10 CFR 39.69 - Radioactive contamination control.  

Code of Federal Regulations, 2011 CFR

... Energy 1 2011-01-01 2011-01-01 false Radioactive contamination control. 39.69 Section 39.69 Energy...WELL LOGGING Radiation Safety Requirements § 39.69 Radioactive contamination control. (a) If the licensee...

2011-01-01

46

10 CFR 39.69 - Radioactive contamination control.  

Code of Federal Regulations, 2010 CFR

... Energy 1 2010-01-01 2010-01-01 false Radioactive contamination control. 39.69 Section 39.69 Energy...WELL LOGGING Radiation Safety Requirements § 39.69 Radioactive contamination control. (a) If the licensee...

2010-01-01

47

10 CFR 39.69 - Radioactive contamination control.  

... Energy 1 2014-01-01 2014-01-01 false Radioactive contamination control. 39.69 Section 39.69 Energy...WELL LOGGING Radiation Safety Requirements § 39.69 Radioactive contamination control. (a) If the licensee...

2014-01-01

48

Chemical states of fallout radioactive Cs in the soils deposited at Fukushima Daiichi Nuclear Power Plant accident  

Microsoft Academic Search

The chemical states of radioactive Cs (caused by Fukushima Daiichi Nuclear Power Plant accident) in the contaminated soils have been characterized by the desorption experiments using appropriate reagent solutions and size fractionation of the contaminated soils. More than 65% of radioactive Cs remained in the residual fraction of the soil samples after treatment of 1 mole L NH4Cl solution and 1 mole

Naofumi Kozai; Toshihiko Ohnuki; Makoto Arisaka; Masayuki Watanabe; Fuminori Sakamoto; Shinya Yamasaki; Mingyu Jiang

2012-01-01

49

Developing effective removal of caesium, strontium and uranium from contaminated soils and sediments  

E-print Network

their migration from the source. One of the handful of contaminated soil and water remediation technologies beingDeveloping effective removal of caesium, strontium and uranium from contaminated soils of radioactively contaminated ground (1, 2) . An immediate priority is the remediation of high activity fission

Burke, Ian

50

Radioactive contamination incidents involving protective clothing  

SciTech Connect

The study focuses on incidents at Department of Energy facilities involving the migration of radioactive contaminants through protective clothing. The authors analyzed 68 occurrence reports for the following factors: (1) type of work, (2) working conditions, (3) type of anti-contamination material; (4) area of body or clothing contaminated; and (5) nature of spread of contamination. A majority of reports identified strenuous work activities such as maintenance, construction, or decontamination and decommissioning projects. The reports also indicated adverse working conditions that included hot and humid or cramped work environments. The type of anti-contamination clothing most often identified was cotton or water-resistant disposable clothing. Most of the reports also indicated contaminants migrating through perspiration-soaked areas, typically in the knees and forearms. On the basis of their survey, the authors recommend the use of improved engineering controls and resilient, breathable, waterproof protective clothing for work in hot, humid, or damp areas where the possibility of prolonged contact with contamination cannot be easily avoided or controlled. 1 ref., 6 figs., 1 tab.

Reichelt, R.A.; Clay, M.E.; Eichorst, A.J. [Los Alamos National Lab., NM (United States)

1998-01-01

51

Radioactive contamination of the Yenisei River  

Microsoft Academic Search

Based on observational data in the period 1971–1993, radioactive contamination of the Yenisei River ecosystem was analysed within 2000 km of the site of discharges from the Krasnoyarsk Mining and Chemical Industrial Complex. Data on the content of 24Na, 32P, 46Sc, 51Cr, 54Mn, 56Mn, 58Co, 60Co, 59Fe, 65Zn, 90Sr, 95Zr, 95Nb, 103Ru, 106Ru, 134Cs, 137Cs, 140Ba, 141Ce, 144Ce and 239Np

E. G. Tertyshnik

1995-01-01

52

Biopiling of creosote contaminated soil  

Microsoft Academic Search

An abandoned wood-treating facility in south Mississippi was the site of a year-long field-scale study. The facility produced creosote-treated railroad cross-ties and marine pilings, and released creosote wastes into the environment for almost forty years. The magnitude of contamination through soil contact, accidental spills, and disposal of creosote wastes in unlined disposal pits was great. Bioremediation of organic compounds has

Kelly Hurt; Hamid Borazjani; Susan V. Diehl; Mary Hannigan

1997-01-01

53

Bioremediating herbicide-contaminated soils  

Microsoft Academic Search

Combinations of landfarming and biostimulation were evaluated for remediating pesticide wastes. Various amounts of soil contaminated\\u000a with alachlor and trifluralin (?100 mg\\/kg each) and metolachlor and atrazine (?20 mg\\/kg each) were applied to field plots,\\u000a and sewage sludge or corn meal was incorporated into designated plots. Plots were also treated with fresh spray mixtures in\\u000a amounts similar to those applied

E. K. Dzantor; A. S. Felsot; M. J. Beck

1993-01-01

54

Radioactive contamination incidents involving protective clothing  

SciTech Connect

The study focuses on incidents at Department of Energy (DOE) facilities involving the migration of radioactive contaminants through protective clothing. The authors analyzed 68 occurrence reports for the following factors: (1) type of work; (2) working conditions; (3) type of anti-contamination (anti-C) material; (4) area of body or clothing contaminated; and (5) nature of spread of contamination. A majority of reports identified strenuous work activities such as maintenance, construction, or decontamination and decommissioning (D&D) projects. The reports also indicated adverse working conditions that included hot and humid or cramped work environments. The type of anti-C clothing most often identified was cotton or water-resistant, disposable clothing. Most of the reports also indicated contaminants migrating through perspiration-soaked areas, typically in the knees and forearms. On the basis of their survey, the authors recommend the use of improved engineering controls and resilient, breathable, waterproof protective clothing for work in hot, humid, or damp areas where the possibility of prolonged contact with contamination cannot be easily avoided or controlled.

Reichelt, R.; Clay, M.; Eichorst, J.

1996-10-01

55

Vegetation helps microbes clean up contaminated soils  

SciTech Connect

According to research sponsored by DOE's Hazardous Waste Remedial Action Program, chemically contaminated soils may be cleaned up more rapidly by soil microorganisms if vegetation is present. The research was done at ORNL using soils collected from the Savannah River Site. It was found that trichloroethylene was decontaminated faster in soils surrounding plant roots than in soil without vegetation.

Not Available

1990-01-01

56

Treatment of NORM contaminated soil from the oilfields.  

PubMed

Uncontrolled disposal of oilfield produced water in the surrounding environment could lead to soil contamination by naturally occurring radioactive materials (NORM). Large volumes of soil become highly contaminated with radium isotopes ((226)Ra and (228)Ra). In the present work, laboratory experiments have been conducted to reduce the activity concentration of (226)Ra in soil. Two techniques were used, namely mechanical separation and chemical treatment. Screening of contaminated soil using vibratory sieve shaker was performed to evaluate the feasibility of particle size separation. The fractions obtained were ranged from less than 38 ?m to higher than 300 ?m. The results show that (226)Ra activity concentrations vary widely from fraction to fraction. On the other hand, leaching of (226)Ra from soil by aqueous solutions (distilled water, mineral acids, alkaline medias and selective solvents) has been performed. In most cases, relatively low concentrations of radium were transferred to solutions, which indicates that only small portions of radium are present on the surface of soil particles (around 4.6%), while most radium located within soil particles; only concentrated nitric acid was most effective where 50% of (226)Ra was removed to aqueous phase. However, mechanical method was found to be easy and effective, taking into account safety procedures to be followed during the implementation of the blending and homogenization. Chemical extraction methods were found to be less effective. The results obtained in this study can be utilized to approach the final option for disposal of NORM contaminated soil in the oilfields. PMID:24378731

Abdellah, W M; Al-Masri, M S

2014-03-01

57

SOIL WASHING TREATABILITY TESTS FOR PESTICIDE- CONTAMINATED SOIL  

EPA Science Inventory

The 1987 Sand Creek Operable Unit 5 record of decision (ROD) identified soil washing as the selected technology to remediate soils contaminated with high levels of organochlorine pesticides, herbicides, and metals. Initial treatability tests conducted to assess the applicability...

58

Approach to bioremediation of contaminated soil  

Microsoft Academic Search

Biological processes, including microbial degradation, have been identified as critical mechanisms for attenuating organic contaminants during transit through the vadose zone to the groundwater. On-site soil remedial measures using biological processes can reduce or eliminate groundwater contamination, thus reducing the need for extensive groundwater monitoring and treatment requirements. On-site remedial systems that utilize the soil as the treatment system accomplish

J. L. Sims; R. C. Sims; J. E. Matthews

1990-01-01

59

Approach to bioremediation of contaminated soil  

Microsoft Academic Search

Biological processes, including microbial degradation, have been identified as critical mechanisms for attenuating organic contaminants during transit through the vadose zone to the groundwater. On-site soil remedial measures using biological processes can reduce or eliminate groundwater contamination, thus reducing the need for extensive groundwater monitoring and treatment requirements. On-site remedial systems that utilize the soil as the treatment system accomplish

J. L. Sims; R. C. Sims; J. E. Matthews

2009-01-01

60

In situ removal of contamination from soil  

DOEpatents

A process of remediation of cationic heavy metal contamination from soil utilizes gas phase manipulation to inhibit biodegradation of a chelating agent that is used in an electrokinesis process to remove the contamination, and further gas phase manipulation to stimulate biodegradation of the chelating agent after the contamination has been removed. The process ensures that the chelating agent is not attacked by bioorganisms in the soil prior to removal of the contamination, and that the chelating agent does not remain as a new contaminant after the process is completed.

Lindgren, Eric R. (Albuquerque, NM); Brady, Patrick V. (Albuquerque, NM)

1997-01-01

61

In situ removal of contamination from soil  

DOEpatents

A process of remediation of cationic heavy metal contamination from soil utilizes gas phase manipulation to inhibit biodegradation of a chelating agent that is used in an electrokinesis process to remove the contamination. The process also uses further gas phase manipulation to stimulate biodegradation of the chelating agent after the contamination has been removed. The process ensures that the chelating agent is not attacked by bioorganisms in the soil prior to removal of the contamination, and that the chelating agent does not remain as a new contaminant after the process is completed. 5 figs.

Lindgren, E.R.; Brady, P.V.

1997-10-14

62

Enhanced biodegradation of creosote-contaminated soil  

Microsoft Academic Search

Bioremediation, a viable option for treatment of cresote-contaminated soil, can be enhanced by the use of surfactant. A study was conducted to investigate the effect of a non-ionic surfactant, Triton X-100, on biodegradation of creosote-contaminated soil. Abiotic soil desorption experiments were performed to determine the kinetics of release of selected polynuclear aromatic hydrocarbon (PAH) compounds. Respirometric experiments were also conducted

Patrick P. E. Carriere; Fehmidakhatun A. Mesania

1995-01-01

63

Bioremediation of munitions-contaminated soils  

SciTech Connect

Military installations nationwide are required to cleanup soils contaminated with ordnance compounds, such as 2,4,6-Trinitrotoluene (TNT), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetraazocine (HMX), and 1,3,5-2,4,2-triazine (RDX), introduced into the environment during the manufacture, use, storage, and disposal of explosives. Numerous laboratory and field studies have confirmed the effectiveness of aerobic biological treatment (composting) for remediation of soils contaminated with these and related nitroaromatics. Composting involves the incubation of contaminated soils with organic amendments under thermophilic conditions (i.e., temperatures between 40 and 70 C). Recently, the remediation of soils contaminated with nitroaromatics has also been demonstrated under anaerobic treatment conditions in bench- and field-scale studies. These studies have involved the incubation of soils in closed reactors or flooded soil cells with obligate anaerobic bacteria. Presented in this paper are the results of parallel bench-scale anaerobic and aerobic treatability studies carried out to aid in the selection of a treatment remedy for nitroaromatic contaminated soils. Bench-scale composting reactors were established by adding organic substrates to each soil at a 70% loading (on a volume basis). To investigate the anaerobic treatment of ordnance compounds, the SIMPLOT proprietary process was evaluated using a consortium of anaerobic bacteria. This process effectively remediated soil contaminated with Dinoseb, a related nitroaromatic compound, when tested in a field demonstration of the technology.

Tuomi, E.; Coover, M.; Stroo, H. [Remediation Technologies, Inc., Seattle, WA (United States)

1994-12-31

64

Issues in recycling and disposal of radioactively contaminated materials  

SciTech Connect

The Department of Energy`s present stock of potentially re-usable and minimally radioactively contaminated materials will increase significantly as the Department`s remediation activities expand. As part of its effort to minimize wastes, the Department is pursuing several approaches to recover valuable materials such as nickel, copper, and steel, and reduce the high disposal costs associated with contaminated materials. Key approaches are recycling radioactively contaminated materials or disposing of them as non-radioactive waste. These approaches are impeded by a combination of potentially conflicting Federal regulations, State actions, and Departmental policies. Actions to promote or implement these approaches at the Federal, State, or Departmental level involve issues which must be addressed and resolved. The paramount issue is the legal status of radioactively contaminated materials and the roles of the Federal and State governments in regulating those materials. Public involvement is crucial in the debate surrounding the fate of radioactively contaminated materials.

Kluk, A.F. [Dept. of Energy, Washington, DC (United States); Hocking, E.K. [Argonne National Lab., Washington, DC (United States); Roberts, R. [Dept. of Energy, San Francisco, CA (United States); Phillips, J.W. [Analytical Services, Inc., Columbia, MD (United States)

1993-10-01

65

Vitrification testing of soil fines from contaminated Hanford 100 Area and 300 Area soils  

SciTech Connect

The suitability of Hanford soil for vitrification is well known and has been demonstrated extensively in other work. The tests reported here were carried out to confirm the applicability of vitrification to the soil fines (a subset of the Hanford soil potentially different in composition from the bulk soil) and to provide data on the performance of actual, vitrified soil fines. It was determined that the soil fines were generally similar in composition to the bulk Hanford soil, although the fraction <0.25 mm in the 100 Area soil sample appears to differ somewhat from the bulk soil composition. The soil fines are readily melted into a homogeneous glass with the simple additions of CaO and/or Na{sub 2}O. The vitrified waste (plus additives) occupies only 60% of the volume of the initial untreated waste. Leach testing has shown the glasses made from the soil fines to be very durable relative to natural and man-made glasses and has demonstrated the ability of the vitrified waste to greatly reduce the release of radionuclides to the environment. Viscosity and electrical conductivity measurements indicate that the soil fines will be readily processable, although with levels of additives slightly greater than used in the radioactive melts. These tests demonstrate the applicability of vitrification to the contaminated soil fines and the exceptional performance of the waste form resulting from the vitrification of contaminated Hanford soils.

Ludowise, J.D.

1994-05-01

66

A petroleum contaminated soil bioremediation facility  

SciTech Connect

The amount of petroleum contaminated soil (PCS) at the Savannah River site (SRS) that has been identified, excavated and is currently in storage has increased several fold during the last few years. Several factors have contributed to this problem: (1) South Carolina Department of Health ad Environmental control (SCDHEC) lowered the sanitary landfill maximum concentration for total petroleum hydrocarbons (TPH) in the soil from 500 to 100 parts per million (ppm), (2) removal and replacement of underground storage tanks at several sites, (3) most recently SCDHEC disallowed aeration for treatment of contaminated soil, and (4) discovery of several very large contaminated areas of soil associated with leaking underground storage tanks (LUST), leaking pipes, disposal areas, and spills. Thus, SRS has an urgent need to remediate large quantities of contaminated soil that are currently stockpiled and the anticipated contaminated soils to be generated from accidental spills. As long as we utilize petroleum based compounds at the site, we will continue to generate contaminated soil that will require remediation.

Lombard, K.; Hazen, T.

1994-06-01

67

Highly reduced mass loss rates and increased litter layer in radioactively contaminated areas.  

PubMed

The effects of radioactive contamination from Chernobyl on decomposition of plant material still remain unknown. We predicted that decomposition rate would be reduced in the most contaminated sites due to an absence or reduced densities of soil invertebrates. If microorganisms were the main agents responsible for decomposition, exclusion of large soil invertebrates should not affect decomposition. In September 2007 we deposited 572 bags with uncontaminated dry leaf litter from four species of trees in the leaf litter layer at 20 forest sites around Chernobyl that varied in background radiation by more than a factor 2,600. Approximately one quarter of these bags were made of a fine mesh that prevented access to litter by soil invertebrates. These bags were retrieved in June 2008, dried and weighed to estimate litter mass loss. Litter mass loss was 40% lower in the most contaminated sites relative to sites with a normal background radiation level for Ukraine. Similar reductions in litter mass loss were estimated for individual litter bags, litter bags at different sites, and differences between litter bags at pairs of neighboring sites differing in level of radioactive contamination. Litter mass loss was slightly greater in the presence of large soil invertebrates than in their absence. The thickness of the forest floor increased with the level of radiation and decreased with proportional loss of mass from all litter bags. These findings suggest that radioactive contamination has reduced the rate of litter mass loss, increased accumulation of litter, and affected growth conditions for plants. PMID:24590204

Mousseau, Timothy A; Milinevsky, Gennadi; Kenney-Hunt, Jane; Møller, Anders Pape

2014-05-01

68

Cleanup of contaminated soil -- Unreal risk assumptions: Contaminant degradation  

SciTech Connect

Exposure assessments for development of risk-based soil cleanup standards or criteria assume that contaminant mass in soil is infinite and conservative (constant concentration). This assumption is not real for most organic chemicals. Contaminant mass is lost from soil and ground water when organic chemicals degrade. Factors to correct for chemical mass lost by degradation are derived from first-order kinetics for 85 organic chemicals commonly listed by USEPA and state agencies. Soil cleanup criteria, based on constant concentration, are then corrected for contaminant mass lost. For many chemicals, accounting for mass lost yields large correction factors to risk-based soil concentrations. For degradation in ground water and soil, correction factors range from greater than one to several orders of magnitude. The long exposure durations normally used in exposure assessments (25 to 70 years) result in large correction factors to standards even for carcinogenic chemicals with long half-lives. For the ground water pathway, a typical soil criterion for TCE of 1 mg/kg would be corrected to 11 mg/kg. For noncarcinogens, correcting for mass lost means that risk algorithms used to set soil cleanup requirements are inapplicable for many chemicals, especially for long periods of exposure.

Schiffman, A. [New Jersey Department of Environmental Protection, Ewing, NJ (United States)

1995-12-31

69

APPROACH TO BIOREMEDIATION OF CONTAMINATED SOIL  

EPA Science Inventory

Biological processes, including microbial degradation, have been identified as critical mechanisms for attenuating organic contaminants during transit through the vadose zone to the groundwater. n-site soil remedial measures using biological processes can reduce or eliminate grou...

70

Cadmium Removal from Contaminated Soil by Tunable  

E-print Network

Cadmium Removal from Contaminated Soil by Tunable Biopolymers G I R I D H A R P R A B H U K U M A R-binding biopolymer with high affinity toward cadmium. By taking advantage of the property of ELPH12 to undergo a reversible thermal precipitation, easy recovery of the sequestered cadmium from contaminated water

Chen, Wilfred

71

Radioactive Waste Disposal Implications of Extending Part IIA to cover Radioactively Contaminated Land  

Microsoft Academic Search

A short study has been carried out of the potential radioactive waste disposal issues associated with the proposed extension of Part IIA to address radioactively contaminated land, where there is no other suitable existing legislation. It was found that there is likely to be an availability problem with respect to disposal at landfills of the radioactive wastes arising from remediation.

DJ Nancarrow

72

An innovative alternative for managing contaminated soils  

Microsoft Academic Search

A property owner was required to remove contaminated fill soils prior to the sale of a 10-ac parcel in an industrialized area of southern California. Based on the concentrations of petroleum hydrocarbons, these soils were originally considered by the regulatory community to represent hazardous waste. Alternatives for their removal or remediation included disposal as hazardous waste at a cost of

1991-01-01

73

RISK ANALYSIS OF TCDD CONTAMINATED SOIL  

EPA Science Inventory

This paper provides a methodology for estimating the human exposure and cancer risk associated with 2,3,7,8-TCDD contaminated soil. Five exposure pathways are addressed: dust inhalation, fish ingestion, dermal absorption, soil ingestion, and beef/dairy products ingestion. For eac...

74

MEMBRANE TECHNOLOGIES FOR REMEDIATING CONTAMINATED SOILS: A CRITICAL REVIEW  

EPA Science Inventory

Regulatory compliance requires the cleanup of soils contaminated with toxic organic and metallic compounds. Several chemical and thermal detoxification technologies have been tested on soils excavated from contaminated sites. Soil washing with aqueous solutions transfers the cont...

75

Surfactant screening of diesel-contaminated soil  

SciTech Connect

At one installation, approximately 60,000 gal of No. 2 diesel fuel leaked into the subsurface environment, with contamination at depths of 6 to 34 m below the surface. Argonne National Laboratory was contracted to perform treatability studies for site remediation. The treatability studies focused on four separate phases: (1) leachability studies on the various contaminated soil borings, (2) air stripping studies, (3) bioremediation studies, and (4) surfactant screening/surfactant flooding studies. This paper summarizes the fourth phase of the research program in which twenty-one surfactants were screened for possible use to mobilize the organics from the contaminated soil prior to bioremediation. Anionic surfactants resulted in the greatest degree of diesel mobilization. The most promising surfactants will be employed on actual contaminated soil samples obtained from the site. 18 refs., 16 figs., 1 tab.

Peters, R.W.; Montemagno, C.D.; Shem, L. (Argonne National Lab., IL (USA)); Lewis, B.A. (Northwestern Univ., Evanston, IL (USA). Dept. of Civil Engineering)

1990-01-01

76

CONTAMINATED SOIL VOLUME ESTIMATE TRACKING METHODOLOGY  

SciTech Connect

The U.S. Army Corps of Engineers (USACE) is conducting a cleanup of radiologically contaminated properties under the Formerly Utilized Sites Remedial Action Program (FUSRAP). The largest cost element for most of the FUSRAP sites is the transportation and disposal of contaminated soil. Project managers and engineers need an estimate of the volume of contaminated soil to determine project costs and schedule. Once excavation activities begin and additional remedial action data are collected, the actual quantity of contaminated soil often deviates from the original estimate, resulting in cost and schedule impacts to the project. The project costs and schedule need to be frequently updated by tracking the actual quantities of excavated soil and contaminated soil remaining during the life of a remedial action project. A soil volume estimate tracking methodology was developed to provide a mechanism for project managers and engineers to create better project controls of costs and schedule. For the FUSRAP Linde site, an estimate of the initial volume of in situ soil above the specified cleanup guidelines was calculated on the basis of discrete soil sample data and other relevant data using indicator geostatistical techniques combined with Bayesian analysis. During the remedial action, updated volume estimates of remaining in situ soils requiring excavation were calculated on a periodic basis. In addition to taking into account the volume of soil that had been excavated, the updated volume estimates incorporated both new gamma walkover surveys and discrete sample data collected as part of the remedial action. A civil survey company provided periodic estimates of actual in situ excavated soil volumes. By using the results from the civil survey of actual in situ volumes excavated and the updated estimate of the remaining volume of contaminated soil requiring excavation, the USACE Buffalo District was able to forecast and update project costs and schedule. The soil volume tracking methodology helped the USACE Buffalo District track soil quantity changes from projected excavation work over time and across space, providing the basis for an explanation of some of the project cost and schedule variances.

Durham, L.A.; Johnson, R.L.; Rieman, C.; Kenna, T.; Pilon, R.

2003-02-27

77

SOIL WASHING TREATABILITY FOR PESTICIDE-CONTAMINATED SOIL  

EPA Science Inventory

The 1987 Record of Decision for Sand Creek Operable Unit 5 identified soil washing as the selected technology to remediate soils contaminated with high levels of organochlorine pesticides, herbicides and metals. nitial treatability tests conducted to assess the application of soi...

78

Simplified method for detecting tritium contamination in plants and soil  

USGS Publications Warehouse

Cost-effective methods are needed to identify the presence and distribution of tritium near radioactive waste disposal and other contaminated sites. The objectives of this study were to (i) develop a simplified sample preparation method for determining tritium contamination in plants and (ii) determine if plant data could be used as an indicator of soil contamination. The method entailed collection and solar distillation of plant water from foliage, followed by filtration and adsorption of scintillation-interfering constituents on a graphitebased solid phase extraction (SPE) column. The method was evaluated using samples of creosote bush [Larrea tridentata (Sesse?? & Moc. ex DC.) Coville], an evergreen shrub, near a radioactive disposal area in the Mojave Desert. Laboratory tests showed that a 2-g SPE column was necessary and sufficient for accurate determination of known tritium concentrations in plant water. Comparisons of tritium concentrations in plant water determined with the solar distillation-SPE method and the standard (and more laborious) toluene-extraction method showed no significant difference between methods. Tritium concentrations in plant water and in water vapor of root-zone soil also showed no significant difference between methods. Thus, the solar distillation-SPE method provides a simple and cost-effective way to identify plant and soil contamination. The method is of sufficient accuracy to facilitate collection of plume-scale data and optimize placement of more sophisticated (and costly) monitoring equipment at contaminated sites. Although work to date has focused on one desert plant, the approach may be transferable to other species and environments after site-specific experiments.

Andraski, B.J.; Sandstrom, M.W.; Michel, R.L.; Radyk, J.C.; Stonestrom, D.A.; Johnson, M.J.; Mayers, C.J.

2003-01-01

79

Enhanced biodegradation of creosote-contaminated soil  

SciTech Connect

Bioremediation, a viable option for treatment of creosote-contaminated soil, can be enhanced by the use of surfactant. A study was conducted to investigate the effect of a non-ionic surfactant, Triton X-100, on biodegradation of creosote-contaminated soil. Abiotic soil desorption experiments were performed to determine the kinetics of release of selected polynuclear aromatic hydrocarbon (PAH) compounds. Respirometric experiments were also conducted to evaluate the effect of nonionic surfactant on biodegradation. The N-Con system respirometer was used to monitor the oxygen uptake by the microorganisms. The abiotic experiments results indicated that the addition of surfactant to soil/water systems increased the desorption of PAH compounds. It was also observed that the desorption rate of PAH compounds depended on their molecular weight. The 3- and 4-ring PAH compounds showed higher and faster desorption rates than the 5- and 6-ring PAHs. The respirometric experiments indicated that an increase in soil contamination level from 112.5 to 771.8 mg/kg showed an increase in oxygen uptake. But for a soil contamination level of 1,102.5 mg/kg, the oxygen uptake was similar to the contamination level of 771.8 mg/kg. This might be due to toxicity by the surfactant or the solubilized PAHs at high concentration or interference with contaminant transport into the cell or to reversible physical-chemical interferences with the activity of enzymes involved in the PAH degradation. The increase in PAH availability to the microorganisms in the aqueous phase produced an increase in oxygen consumption that is proportional to the biodegradation of organic compounds.

Carriere, P.P.E.; Mesania, F.A. [West Virginia Univ., Morgantown, WV (United States). Dept. of Civil and Environmental Engineering] [West Virginia Univ., Morgantown, WV (United States). Dept. of Civil and Environmental Engineering

1995-12-31

80

Thermal desorption of petroleum contaminated soils  

SciTech Connect

The US Environmental Protection Agency recently funded a study which addresses the treatment of soils contaminated by petroleum hydrocarbons using low temperature thermal desorption (LTTD). The proposed paper will summarize some of the results of that study. LTTD has become a major petroleum contaminated soil remediation technology. The paper will define LTTD and discuss fundamental thermal desorption mechanisms such as hydrocarbon vapor pressure, steam stripping and soil characteristics. Full-scale LTTD equipment such as asphalt kilns, rotary dryers, thermal screws and indirect fired calciners will be described. Typical off-gas treatment equipment such as afterburners, baghouses, wet scrubbers, carbon and condensation/recovery will also be discussed. Full-scale LTTD performance data, such as hydrocarbon destruction efficiency, carbon monoxide and particulate stack concentrations, and soil total petroleum hydrocarbon residuals will be summarized.

Troxler, W.L.; Yezzi, J.J.; Cudahy, J.J.; Rosenthal, S.I.

1992-01-01

81

Bioremediation of glyphosate-contaminated soils  

Microsoft Academic Search

Based on the results of laboratory and field experiments, we performed a comprehensive assessment of the bioremediation efficiency\\u000a of glyphosate-contaminated soddy-podzol soil. The selected bacterial strains Achromobacter sp. Kg 16 (VKM B-2534D) and Ochrobactrum anthropi GPK 3 (VKM B-2554D) were used for the aerobic degradation of glyphosate. They demonstrated high viability in soil with the\\u000a tenfold higher content of glyphosate

Inna T. Ermakova; Nina I. Kiseleva; Tatyana Shushkova; Mikhail Zharikov; Gennady A. Zharikov; Alexey A. Leontievsky

2010-01-01

82

Solid phase bioremediation of petroleum contaminated soils  

SciTech Connect

Solid phase bioremediation of petroleum contaminated soil involves aerobic biodegradation in an above grade treatment bed. This treatment technology is proposed for remediating soils contaminated by petroleum from leaking underground fuel storage tanks at various sites at the Oak Ridge Y-12 Plant. The treatment technology uses bacteria to degrade the petroleum hydrocarbons. The environmentally safe end products of the biodegradation process are carbon dioxide and water. A large, relatively level area is required to construct the perimeter berms, place the liner, and spread the contaminated soil in a 1 to 2 foot thick layer. A porous media is placed on top of the liner for protection and for proper drainage of leachate. Water, nutrients, and microorganisms are introduced into the soil in the treatment bed using conventional agricultural spraying techniques. Oxygen is supplied to the soil by periodic tilling on an ``as needed`` basis. To prevent soil erosion and to minimize leachate production during precipitation events, the treatment bed is completely covered by a plastic film. The treatment process is expected to require 3 to 8 months after construction is completed.

Potter, C.D. [Science Applications International Corp., Oak Ridge, TN (United States)

1992-11-01

83

Solid phase bioremediation of petroleum contaminated soils  

SciTech Connect

Solid phase bioremediation of petroleum contaminated soil involves aerobic biodegradation in an above grade treatment bed. This treatment technology is proposed for remediating soils contaminated by petroleum from leaking underground fuel storage tanks at various sites at the Oak Ridge Y-12 Plant. The treatment technology uses bacteria to degrade the petroleum hydrocarbons. The environmentally safe end products of the biodegradation process are carbon dioxide and water. A large, relatively level area is required to construct the perimeter berms, place the liner, and spread the contaminated soil in a 1 to 2 foot thick layer. A porous media is placed on top of the liner for protection and for proper drainage of leachate. Water, nutrients, and microorganisms are introduced into the soil in the treatment bed using conventional agricultural spraying techniques. Oxygen is supplied to the soil by periodic tilling on an as needed'' basis. To prevent soil erosion and to minimize leachate production during precipitation events, the treatment bed is completely covered by a plastic film. The treatment process is expected to require 3 to 8 months after construction is completed.

Potter, C.D. (Science Applications International Corp., Oak Ridge, TN (United States))

1992-01-01

84

Evaluation of soil washing for radiologically contaminated soils  

SciTech Connect

Soil washing has been applied internationally to decontaminate soils due to the widespread increase in environmental awareness manifested in the United States by promulgation of the Comprehensive Environmental Response, Compensation and Liability Act, yet we continue to lack understanding on why the technique works in one application and not in another. A soil washing process typically integrates a variety of modules, each designed to decontaminate the matrix by destroying a particular phase or segregating a particle size fraction in which the contaminants are concentrated. The more known about how the contaminants are fixed, the more likely the process will succeed. Much can be learned from bioavailability studies on heavy metals in soils. Sequential extraction experiments designed to destroy one fixation mechanism at a time can be used to determine how contaminants are bound. This knowledge provides a technical basis for designing a processing strategy to efficiently decontaminate soil while creating a minimum of secondary wastes. In this study, a soil from the Idaho National Engineering Laboratory was physically and chemically characterized, then sequentially extracted to determine if soil washing could be effectively used to remove cesium, cobalt and chromium.

Gombert, D. II

1994-03-01

85

STUDIES ON THE DEPOSITION AND REMOVAL OF RADIOACTIVE SOIL  

Microsoft Academic Search

The rate of deposition and removal of a radioactive milk soil from ; several surfaces have been studied. The nature of the surface exhibited a small ; but measurable effect on the rate of deposition of a radioactive milk soil on the ; surfaces tested. However, the surfaces showed no significant effect on the rate ; of soil removal. The

I. J. Pflug; T. I. Hedrick; O. W. Kaufmann; R. A. Keppeler; C. G. Pheil

1961-01-01

86

BIOREMEDIATION OF URANIUM CONTAMINATED SOILS AND WASTES  

Microsoft Academic Search

Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (i) stabilization of uranium and toxic metals with reduction

1998-01-01

87

Bioremediation of uranium contaminated soils and wastes  

Microsoft Academic Search

Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (1) stabilization of uranium and toxic metals with reduction

1998-01-01

88

INCINERATION TREATMENT OF ARSENIC-CONTAMINATED SOIL  

EPA Science Inventory

An incineration test program was conducted at the US Environmental Protection Agency's Incineration Research Facility to evaluate the potential of incineration as a treatment option for contaminated soils at the Baird and McGuire Superfund site in Holbrook, Massachusetts. he purp...

89

INCINERATION TREATMENT OF ARSENIC-CONTAMINATED SOIL  

EPA Science Inventory

An incineration test program was conducted at the U.S. Environmental Protection Agency's Incineration Research Facility to evaluate the potential of incineration as a treatment option for contaminated soils at the Baird and McGuire Superfund site in Holbrook, Massachusetts. The p...

90

THERMAL DESORPTION OF PETROLEUM CONTAMINATED SOILS  

EPA Science Inventory

The U.S. Environmental Protection Agency recently funded a study which addresses the treatment of soils contaminated by petroleum hydrocarbons using low temperature thermal desorption (LTTD). he proposed paper will summarize some of the results of that study. TTD has become a maj...

91

REMEDIATION OF PCB IN CONTAMINATED SOIL  

EPA Science Inventory

A pilot-scale study will be conducted to evaluate the bioremedial techniques of natural attenuation, sequenced anaerobic/aerobic treatment, and addition of a commercially available microbial amendment product for use in treating PCB contaminated soils at Air Force Base sites. Th...

92

REMEDIATION OF RADIUM FROM CONTAMINATED SOIL  

EPA Science Inventory

The objective of this study was to demonstrate the application of a physico-chemical separation process for the removal of radium from a sample of contaminated soil at the Ottawa, Illinois, site near Chicago. The size/activity distribution analyzed among the particles coarser tha...

93

REMEDIATING PESTICIDE CONTAMINATED SOILS USING SOLVENT EXTRACTION  

EPA Science Inventory

Bench-scale solvent extraction studies were performed on soil samples obtained from a Superfund site contaminated with high levels of p,p'-DDT, p,p'-DDD,, p,p'-DDE and toxaphene. The effectiveness of the solvent extraction process was assessed using methanol and 2-propanol as sol...

94

Contamination analysis of radioactive samples in focused ion beam instruments.  

PubMed

The use of Focused Ion Beam (FIB) instrument's to analyze and prepare samples that are radioactive requires attentiveness to the materials that are dislodged and free inside the chamber. Radioactive sputtered material must be understood even when observed at trace concentrations. Measurements using liquid scintillation counting and high purity germanium detectors were used to evaluate contamination on accessible surfaces inside a focused ion beam chamber that was used in the preparation of samples that were radioactive. The maximum removable contamination found was 0.27 0.4 Bq cm(-2), on the focused ion beam wall with 0.24 0.019 Bq cm(-2) on the door. Although these magnitudes of removable contamination are inconsequential for activation products, these same magnitudes of actinides, for example 239Pu, would represent 3.2% of an Annual Limit of Intake. This might be considered significant if one examines the relatively infrequent use of this device for the preparation of radioactive samples. Predicted activities of sputtered material were found using the software Transport of Ions in Matter, estimating that 0.003% of a radioactive samples activity is released into the FIB chamber. A used secondary electron detector's activity was measured to be 383.7 8.1 Bq. Preferential build-up of sputtered materials due to temperature or static charge gradients was considered. No temperature gradients were observed. Static charge gradients were measured inside the chamber varying between 0.057% below the mean to 34% higher than the mean. However, the magnitudes of contamination measured did not correlate to static charge gradients. Deposition in the chamber appears to have no mechanical cause but rather is sporadic however, measureable. Experience to date has been limited to samples of low activity; nevertheless, contamination inside the chamber was observed. Users should anticipate higher levels of readily dispersible radioactive contamination within the FIB as sample activity increases. PMID:23287516

Evelan, Audrey Ruth; Brey, Richard R

2013-02-01

95

Evolution of radioactive dose rates in fresh sediment deposits along coastal rivers draining Fukushima contamination plume  

NASA Astrophysics Data System (ADS)

Measurement of radioactive dose rates in fine sediment that has recently deposited on channel bed-sand provides a solution to address the lack of continuous river monitoring in Fukushima Prefecture after Fukushima Dai-ichi nuclear power plant (FDNPP) accident. We show that coastal rivers of Eastern Fukushima Prefecture were rapidly supplied with sediment contaminated by radionuclides originating from inland mountain ranges, and that this contaminated material was partly exported by typhoons to the coastal plains as soon as by November 2011. This export was amplified during snowmelt and typhoons in 2012. In 2013, contamination levels measured in sediment found in the upper parts of the catchments were almost systematically lower than the ones measured in nearby soils, whereas their contamination was higher in the coastal plains. We thereby suggest that storage of contaminated sediment in reservoirs and in coastal sections of the river channels now represents the most crucial issue.

Evrard, Olivier; Chartin, Caroline; Onda, Yuichi; Patin, Jeremy; Lepage, Hugo; Lefèvre, Irène; Ayrault, Sophie; Ottlé, Catherine; Bonté, Philippe

2013-10-01

96

Evolution of radioactive dose rates in fresh sediment deposits along coastal rivers draining Fukushima contamination plume  

PubMed Central

Measurement of radioactive dose rates in fine sediment that has recently deposited on channel bed-sand provides a solution to address the lack of continuous river monitoring in Fukushima Prefecture after Fukushima Dai-ichi nuclear power plant (FDNPP) accident. We show that coastal rivers of Eastern Fukushima Prefecture were rapidly supplied with sediment contaminated by radionuclides originating from inland mountain ranges, and that this contaminated material was partly exported by typhoons to the coastal plains as soon as by November 2011. This export was amplified during snowmelt and typhoons in 2012. In 2013, contamination levels measured in sediment found in the upper parts of the catchments were almost systematically lower than the ones measured in nearby soils, whereas their contamination was higher in the coastal plains. We thereby suggest that storage of contaminated sediment in reservoirs and in coastal sections of the river channels now represents the most crucial issue. PMID:24165695

Evrard, Olivier; Chartin, Caroline; Onda, Yuichi; Patin, Jeremy; Lepage, Hugo; Lefevre, Irene; Ayrault, Sophie; Ottle, Catherine; Bonte, Philippe

2013-01-01

97

Applications of RESRAD family of computer codes to sites contaminated with radioactive residues.  

SciTech Connect

The RESIL4D family of computer codes was developed to provide a scientifically defensible answer to the question ''How clean is clean?'' and to provide useful tools for evaluating human health risk at sites contaminated with radioactive residues. The RESRAD codes include (1) RESRAD for soil contaminated with radionuclides; (2) RESRAD-BUILD for buildings contaminated with radionuclides; (3) RESRAD-CHEM for soil contaminated with hazardous chemicals; (4) RESRAD-BASELINE for baseline risk assessment with measured media concentrations of both radionuclides and chemicals; (5) RESRAD-ECORISK for ecological risk assessment; (6) RESRAD-RECYCLE for recycle and reuse of radiologically contaminated metals and equipment; and (7) RESRAD-OFFSITE for off-site receptor radiological dose assessment. Four of these seven codes (RESRAD, RESRAD-BUILD, RESRAD-RECYCLE, and RESRAD-OFFSITE) also have uncertainty analysis capabilities that allow the user to input distributions of parameters. RESRAD has been widely used in the United States and abroad and approved by many federal and state agencies. Experience has shown that the RESRAD codes are useful tools for evaluating sites contaminated with radioactive residues. The use of RESRAD codes has resulted in significant savings in cleanup cost. Analysis of 19 site-specific uranium guidelines is discussed in the paper.

Yu, C.; Kamboj, S.; Cheng, J.-J.; LePoire, D.; Gnanapragasam, E.; Zielen, A.; Williams, W. A.; Wallo, A.; Peterson, H.

1999-10-21

98

TREATMENT OF HAZARDOUS PETROLEUM CONTAMINATED SOILS BY THERMAL DESORPTION TECHNOLOGIES  

EPA Science Inventory

Spills, leaks, and accidental discharges of petroleum products have contaminated soil at thousands of sites in the United States. ne remedial action technique for treating petroleum contaminated soil is the use of thermal desorption technologies. his paper describes key elements ...

99

Radioactivity in Virgin Soils and Soils from Some Areas with Closed Uranium Mining Facilities in Bulgaria  

NASA Astrophysics Data System (ADS)

The soil radioecology is an important part of the environmental research in the country. Since the beginning of the 1970's regular monitoring of the content of different radionuclides in Bulgarian soils has been done. Objective of the studies were virgin soils from high mountain areas, hills and plains (the region of Kozloduy NPP and the Danube river valley). Natural and men-made radionuclides were observed. In the 25-year period after the the contamination with radionuclides due to the 1986 Chernobyl NPP accident a rich data base has been collected, recording the radiation status of the soils in Bulgaria. Special attention has been paid to the contamination with the long-lived technogenic radionuclides caesium-137 and strontium-90. This paper presents a summary of the obtained results. Caesium-137 and strontium-90 were the main men-made radionuclides detected in the examined Bulgarian soils few years after the Chernobyl NPP accident. Their content in the soils from high mountain areas (Rodopa and Rila mountains) is several times higher than that in the soils from North Bulgaria and Sofia fields. High non-homogenity in the pollution within small areas (even as small as several square meters) has been observed. Natural radioactivity was also studied. Averaged values for natural radionuclides like uranium-238, thorium-232, and radium-226 in virgin soils from different areas in the country are presented. A comparison of the dynamics of their behavior throughout the years is done. Bulgaria is a country with intensive uranium mining activities in the past years. That is why radiological monitoring of closed uranium mining facilities in different regions of the country are obligatory and of great interest. This work presents results from such investigations made in regions where remediation has been done. The results have been evaluated according to the Bulgarian radionuclide environment contamination legislation. The necessity of permanent environmental monitoring is assessed.

Yordanova, I.; Staneva, D.; Misheva, L.; Bineva, Ts.; Banov, M.

2012-04-01

100

Test and evaluation of radioactively contaminated transducers and transmitters  

SciTech Connect

People in the nuclear industries face some unique problems when handling, testing, or examining transducers and transmitters that have been radioactively contaminated. Although many people and organizations, including EG and G Idaho, have performed such work for many years, there are no set, structured approaches or procedures. This paper discusses a disciplined laboratory approach to contaminated transducer testing and evaluation, utilizing equipment and facilities developed specifically for this type of work.

Strahm, R.C.

1983-01-01

101

Radioactive Elements in Soils of Siberia (Russia)  

NASA Astrophysics Data System (ADS)

The Center of State Sanitary and Epidemiological Surveillance Department in Krasnoyarsk Territory, Krasnoyarsk In the course of long-term research a great deal of information on the content of natural and artificial radionuclides in soils of the Siberian regions has been obtained and summarized (Altai and Krasnoyarsk Territories, Altai Republic, Buryatia, Yakutia, Khakassia, Irkutsk, Novosibirsk, Tomsk Oblasts and a number of other Siberian regions). The content level of U(Ra), Th and K in soil of studied areas is within the range of values obtained for soil of other areas of Russia and the world and defined, first of all, by radioactivity of parent rocks. The authors have studied the total level of specific activity for 137Cs most completely in soils of different Siberian regions. The maximum density of such sites with global fallouts (nuclear air explosions in Novaya Zemlya, Lop Nor, Semipalatinsk etc.) is typical for the areas of Altai Territory and Buryatia Republic. Elevated level of radiocesium (to 1000 and more than Bq/kg) is characteristic for the sites adjacent to the area of NFP (Seversk, Zheleznogorsk). Our data obtained in determination of plutonium in soils of different Siberian regions excess remarkably its background accepted for Siberia. Particularly high accumulation levels of Pu in soil were observed in the zones of NFP operation (Seversk, Tomsk Oblast; Zheleznogorsk, Krasnoyarsk Territory, in the sites of accidents fallouts at underground nuclear explosions in Sakha Republic (Yakutia). Abnormally high ratio of 238Pu/239,240Pu in soils of Sakha republic, Aginsk Buryatia Autonomous District, Krasnoyarsk Territory has engaged our attention.

Baranovskaya, N. V.; Rikhvanov, L. P.; Matveenko, I. N.; Strakhovenko, V. D.; Malikova, I. N.; Shcherbakov, B. L.; Sukhorukov, F. V.; Aturova, V. P.

2012-04-01

102

Guide to treatment technology for contaminated soils  

SciTech Connect

This document is a guide for the screening of alternative treatment technologies for contaminated soils. The contents of this guide are organized into: 1. Introduction, II. Utilizing the table, III. Tables: Contamination Versus Technology, TV. Contaminant Waste Groups, and V. References. The four Contaminations Versus Technology tables are designed to identify the effectiveness and/or potential applicability of technologies to some or all compounds within specific waste groups. The tables also present limitations and special use considerations for the particular treatment technology. The phase of development of the technology is also included in the table. The phases are: Available, Innovative, and Emerging technologies. The technologies presented in this guide are organized according to the method of treatment. The four (4) treatment methods are Biological, Solidification/Stabilization, Thermal, and Chemical/Physical Treatment. There are several processing methods; some are well developed and proven, and others are in the development stage.

Tran, H.; Aylward, R.

1992-08-04

103

In-Situ Thermal Remediation of Contaminated Soil1  

E-print Network

Chapter 1 In-Situ Thermal Remediation of Contaminated Soil1 Written by Huaxiong Huang,2 Serguei Lapin and Rex Westbrook 1.1 Background Recently, a method for removing contaminants from soil (several as follows. Over a period of several weeks, electrical energy is introduced to the contaminated soil using

Lapin, Sergey

104

Evaluation of soil radioactivity data from the Nevada Test Site  

SciTech Connect

Since 1951, 933 nuclear tests have been conducted at the Nevada Test Site (NTS) and test areas on the adjacent Tonopah Test Range (TTR) and Nellis Air Force Range (NAFR). Until the early 1960s. the majority of tests were atmospheric, involving detonation of nuclear explosive devices on the ground or on a tower, suspended from a balloon or dropped from an airplane. Since the signing of the Limited Test Ban Treaty in 1963, most tests have been conducted underground, although several shallow subsurface tests took place between 1962 and 1968. As a result of the aboveground and near-surface nuclear explosions, as well as ventings of underground tests, destruction of nuclear devices with conventional explosives, and nuclear-rocket engine tests, the surface soil on portions of the NTS has been contaminated with radionuclides. Relatively little consideration was given to the environmental effects of nuclear testing during the first two decades of operations at the NTS. Since the early 1970s, however, increasingly strict environmental regulations have forced greater attention to be given to contamination problems at the site and how to remediate them. One key element in the current environmental restoration program at the NTS is determining the amount and extent of radioactivity in the surface soil. The general distribution of soil radioactivity on the NTS is already well known as a result of several programs carried out in the 1970s and 1980s. However, questions have been raised as to whether the data from those earlier studies are suitable for use in the current environmental assessments and risk analyses. The primary purpose of this preliminary data review is to determine to what extent the historical data collected at the NTS can be used in the characterization/remediation process.

NONE

1995-03-01

105

Method for treatment of soils contaminated with organic pollutants  

DOEpatents

A method for treating soil contaminated by organic compounds wherein an ozone containing gas is treated with acid to increase the stability of the ozone in the soil environment and the treated ozone applied to the contaminated soil to decompose the organic compounds. The soil may be treated in situ or may be removed for treatment and refilled.

Wickramanayake, Godage B. (Cranbury, NJ)

1993-01-01

106

Health effects associated with exposure to radioactively contaminated gold rings  

Microsoft Academic Search

This study was designed to assess the health risks associated with exposure to radioactively contaminated gold rings. A group of 135 exposed individuals, who were identified through a statewide jewelry screening program, were studied to determine the frequency of carcinoma and other skin problems on the ring finger. Severity of skin problems increased with increasing length of wear. Forty-one of

M. S. Baptiste; R. Rothenberg; P. C. Nasca; D. T. Janerich; C. D. Stutzman; K. Rimawi; W. OBrien; J. Matuszek

1984-01-01

107

Modeling the transport of radioactive contaminants in the arctic  

Microsoft Academic Search

A coupled ice-ocean model, designed by the Naval Research Laboratory, composed of the Cox ocean model coupled to the Hibler ice model is used to simulate the dispersion of radioactive contaminants in the Arctic and its marginal seas. Source locations and estimated inventories of disposed radionuclides are based on those documented in a Russian report referred to as the Yablokov

Ruth H Preller; Abe Cheng

1999-01-01

108

Radioactive contamination of aquatic ecosystems following the Chernobyl accident  

Microsoft Academic Search

The dynamics of radioactive contamination of aquatic ecosystems (1986–1990) is considered on the basis of observational data in the near and distant zones of the Chernobyl fallout (the Chernobyl Nuclear Power Plant (CNPP) cooling pond, the Pripyat River, the Dnieper reservoirs, and the Kopor inlet of the Gulf of Finland). Radionuclide accumulation in aquatic biota is analyzed.The results obtained indicate

I. I. Kryshev

1995-01-01

109

Attenuating organic contaminant mobility by soil modification  

Microsoft Academic Search

Low organic matter clays, soils and aquifer materials have very little sorptive capability for common groundwater contaminants. Here we use organic cations of the form [(CH3)3NR]+ to displace naturally occurring exchange ions resulting in significantly higher organic matter contents, and greatly enhanced sorptive properties for nonionic organic solutes. The organic phase derived from exchanged hexadecyltrimethylammonium, where R is a C-16

Stephen A. Boyd; Jiunn-Fwu Lee; Max M. Mortland

1988-01-01

110

Remediating pesticide contaminated soils using solvent extraction  

SciTech Connect

Bench-scale solvent extraction studies were performed on soil samples obtained from a Superfund site contaminated with high levels of p,p{prime}-DDT, p,p{prime}-DDE and toxaphene. The effectiveness of the solvent extraction process was assessed using methanol and 2-propanol as solvents over a wide range of operating conditions. It was demonstrated that a six-stage methanol extraction using a solvent-to-soil ratio of 1.6 can decrease pesticide levels in the soil by more than 99% and reduce the volume of material requiring further treatment by 25 times or more. The high solubility of the pesticides in methanol resulted in rapid extraction rates, with the system reaching quasi-equilibrium state in 30 minutes. The extraction efficiency was influenced by the number of extraction stages, the solvent-to-soil ratio, and the soil moisture content. Various methods were investigated to regenerate and recycle the solvent. Evaporation and solvent stripping are low cost and reliable methods for removing high pesticide concentrations from the solvent. For low concentrations, GAC adsorption may be used. Precipitating and filtering pesticides by adding water to the methanol/pesticide solution was not successful when tested with soil extracts. 26 refs., 10 figs., 6 tabs.

Sahle-Demessie, E.; Meckes, M.C.; Richardson, T.L. [National Management Research Lab., Cincinnati, OH (United States)

1996-12-31

111

[Migration of industrial radionuclides in soils and benthal deposits at the coastal margins of the temporary waste storage facility (TWSF) of the Northwest Center for Radioactive Waste Management (SevRAO) and its influence on the possible contamination of the sea offshore waters].  

PubMed

For obtaining the integral information about the current radiation situation in the sea offshore waters of the temporary waste storage facility (TWSF) of the Northwest Center for Radioactive Waste Management "SevRAO" in the Andreeva Bay and in the settle Gremikha with a purpose of a comprehensive assessment of its condition there was performed radiation-ecological monitoring of the adjacent sea offshore waters of the TWSF. It was shown that in the territory of industrial sites of the TWSF as a result of industrial activity there are localized areas of pollution by man-made radionuclides. As a result of leaching of radionuclides by tidal stream, snowmelt and rainwater radioactive contamination extends beyond the territory of the sanitary protection zone and to the coastal sea offshore waters. To confirm the coastal pollution of the sea offshore waters the levels of mobility of 90Sr and 137Cs in environmental chains and bond strength of them with the soil and benthal deposits were clarified by determining with the method of detection of the forms of the presence of radionuclides in these media. There was established a high mobility of 137Cs and 90Sr in soils and benthal deposits (desorption coefficient (Kd) of 137Cs and 90Sr (in soils - 0.56 and 0.98), in the sediments - 0.82). The migration of radionuclides in environmental chains can lead to the contamination of the environment, including the sea offshore waters. PMID:25051732

Filonova, A A; Seregin, V A

2014-01-01

112

Industrial-Scale Processes For Stabilizing Radioactively Contaminated Mercury Wastes  

SciTech Connect

This paper describes two industrial-scaled processes now being used to treat two problematic mercury waste categories: elemental mercury contaminated with radionuclides and radioactive solid wastes containing greater than 260-ppm mercury. The stabilization processes were developed by ADA Technologies, Inc., an environmental control and process development company in Littleton, Colorado. Perma-Fix Environmental Services has licensed the liquid elemental mercury stabilization process to treat radioactive mercury from Los Alamos National Laboratory and other DOE sites. ADA and Perma-Fix also cooperated to apply the >260-ppm mercury treatment technology to a storm sewer sediment waste collected from the Y-12 complex in Oak Ridge, TN.

Broderick, T. E.; Grondin, R.

2003-02-24

113

Bioremediation of soils contaminated with explosives.  

PubMed

The large-scale industrial production and processing of munitions such as 2,4,6-trinitrotoluene (TNT) over the past 100 years led to the disposal of wastes containing explosives and nitrated organic by-products into the environment. In the US, the Army alone has estimated that over 1.2 million tons of soil have been contaminated with explosives, and the impact of explosives contamination in other countries is of similar magnitude. In recent years, growing concern about the health and ecological threats posed by man-made chemicals have led to studies of the toxicology of explosives, which have identified toxic and mutagenic effects of the common military explosives and their transformation products (Bruns-Nagel et al., 1999a; Fuchs et al., 2001; Homma-Takeda et al., 2002; Honeycutt et al., 1996; Rosenblatt et al., 1991; Spanggord et al., 1982; Tan et al., 1992 and Won et al., 1976). Because the cleanup of areas contaminated by explosives is now mandated because of public health concerns, considerable effort has been invested in finding economical remediation technologies. Biological treatment processes are often considered, since these are usually the least expensive means of destroying organic pollution. This review examines the most important groups of chemicals that must be treated at sites contaminated by explosives processing, the chemical and biological transformations they undergo, and commercial processes developed to exploit these transformations for treatment of contaminated soil. We critically examine about 150 papers on the topic, including approximately 60 published within the past 5 years. PMID:15016438

Lewis, Thomas A; Newcombe, David A; Crawford, Ronald L

2004-04-01

114

Enhanced bioremediation of PAH contaminated soils from coal processing sites  

SciTech Connect

The polycyclic aromatic hydrocarbons (PAH) are a potential hazard to health due to their carcinogenic, mutagenic nature and acute toxicity and there is an imminent need for remediation of PAH contaminated soils abounding the several coke oven and town gas sites. Aerobic biological degradation of PAHs is an innovative technology and has shown high decontamination efficiencies, complete mineralization of contaminants, and is environmentally safe. The present study investigates the remediation of PAH contaminated soils achieved using Acinetobacter species and fungal strain Phanerochaete Chrysosporium. The soil used for the experiments was an industrially contaminated soil obtained from Alberta Research Council (ARC) primary cleanup facility, Alberta, Canada. Soil characterization was done using High Performance Liquid Chromatography (HPLC) to qualitatively and quantitatively determine the contaminants in the soil. Artificially contaminated soil was also used for some experiments. All the experiments were conducted under completely mixed conditions with suitable oxygen and nutrient amendments. The removal efficiency obtained for various PAHs using the two microorganisms was compared.

Joshi, M.M.; Lee, S. [Univ. of Akron, OH (United States)

1995-12-31

115

The organic contamination level based on the total soil mass is not a proper index of the soil contamination intensity  

USGS Publications Warehouse

Concentrations of organic contaminants in common productive soils based on the total soil mass give a misleading account of actual contamination effects. This is attributed to the fact that productive soils are essentially water-saturated, with the result that the soil uptake of organic compounds occurs principally by partition into the soil organic matter (SOM). This report illustrates that the soil contamination intensity of a compound is governed by the concentration in the SOM (Com) rather than by the concentration in whole soil (Cs). Supporting data consist of the measured levels and toxicities of many pesticides in soils of widely differing SOM contents and the related levels in in-situ crops that defy explanation by the Cs values. This SOM-based index is timely needed for evaluating the contamination effects of food crops grown in different soils and for establishing a dependable priority ranking for intended remediation of numerous contamination sites.

Hung, H. -W.; Daniel, Sheng, G.; Lin, T. -F.; Su, Y.; Chiou, C. T.

2009-01-01

116

Auxiliary analyses in support of performance assessment of a hypothetical low-level waste facility: Two-phase flow and contaminant transport in unsaturated soils with application to low-level radioactive waste disposal. Volume 2  

SciTech Connect

A numerical model of multiphase air-water flow and contaminant transport in the unsaturated zone is presented. The multiphase flow equations are solved using the two-pressure, mixed form of the equations with a modified Picard linearization of the equations and a finite element spatial approximation. A volatile contaminant is assumed to be transported in either phase, or in both phases simultaneously. The contaminant partitions between phases with an equilibrium distribution given by Henry`s Law or via kinetic mass transfer. The transport equations are solved using a Galerkin finite element method with reduced integration to lump the resultant matrices. The numerical model is applied to published experimental studies to examine the behavior of the air phase and associated contaminant movement under water infiltration. The model is also used to evaluate a hypothetical design for a low-level radioactive waste disposal facility. The model has been developed in both one and two dimensions; documentation and computer codes are available for the one-dimensional flow and transport model.

Binning, P. [Newcastle Univ., NSW (Australia); Celia, M.A.; Johnson, J.C. [Princeton Univ., NJ (United States). Dept. of Civil Engineering and Operations Research

1995-05-01

117

Electron Microbeam Investigation of Uranium-Contaminated Soils from  

E-print Network

Research Electron Microbeam Investigation of Uranium-Contaminated Soils from Oak Ridge, TN, USA J O Street, Bloomington, Indiana 47405 Two samples of uranium-contaminated soil from the Department of Energy and transmission electron microscopy. The objectives of this research were to identify and characterize soil

Zhu, Chen

118

SIMULATION OF REMEDIATION ALTERNATIVES FOR A 137Cs CONTAMINATED SOIL.  

E-print Network

SIMULATION OF REMEDIATION ALTERNATIVES FOR A 137Cs CONTAMINATED SOIL. THE NUMERICAL MODELING analyze remediation alternatives for a soil contaminated with 137Cs, which sorbs strongly onto the clayey. Geological setting 2. Hydrogeological setting 3. Remediation alternatives of soil n Reactive transport

Politècnica de Catalunya, Universitat

119

Sites in the United States contaminated with radioactivity.  

PubMed

Over the century that radioactive materials have been mined, processed, produced, and utilized, many sites across the United States have become contaminated. Such sites include bases and installations of the Department of Defense, weapons production and research facilities of the Department of Energy, properties under the authority of other Federal agencies, privately-owned and governmental facilities that are licensed by the Nuclear Regulatory Commission and its Agreement States, and sites licensed by or the responsibility of states. This review reports on aspects of work by the Environmental Protection Agency, the Department of Defense, the Department of Energy, the Nuclear Regulatory Commission, and others to identify sites contaminated with radioactive materials. It also describes the principal programs that have been instituted to deal with them. PMID:10456495

Wolbarst, A B; Blom, P F; Chan, D; Cherry, R N; Doehnert, M; Fauver, D; Hull, H B; MacKinney, J A; Mauro, J; Richardson, A C; Zaragoza, L

1999-09-01

120

ISOCELL trademark proof-of-concept for retrieval of wastes and contaminated soil  

SciTech Connect

ISOCELL{sup TM} cryogenic technology is designed to immobilize buried hazardous, radioactive, and mixed waste and contaminated soil by creating a block of frozen waste and soil that can be safely retrieved, stored, transported, and treated with a minimum of dust or aerosol production. A proof-of-concept'' test of the ISOCELL process was conducted in clean soil by RKK, Ltd., for the Idaho National Engineering Laboratory (INEL). Results indicate ISOCELL technology successfully froze moist soil into a solid block capable of being lifted and retrieved. Test conditions were compared to characteristics of possible buried waste sites in the INEL.

Chatwin, T.D. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Krieg, R.K. (RKK, Ltd., Bellevue WA (United States))

1992-01-01

121

ISOCELL{trademark} proof-of-concept for retrieval of wastes and contaminated soil  

SciTech Connect

ISOCELL{sup TM} cryogenic technology is designed to immobilize buried hazardous, radioactive, and mixed waste and contaminated soil by creating a block of frozen waste and soil that can be safely retrieved, stored, transported, and treated with a minimum of dust or aerosol production. A ``proof-of-concept`` test of the ISOCELL process was conducted in clean soil by RKK, Ltd., for the Idaho National Engineering Laboratory (INEL). Results indicate ISOCELL technology successfully froze moist soil into a solid block capable of being lifted and retrieved. Test conditions were compared to characteristics of possible buried waste sites in the INEL.

Chatwin, T.D. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Krieg, R.K. [RKK, Ltd., Bellevue WA (United States)

1992-08-01

122

REVIEW OF SEPARATION TECHNOLOGIES FOR TREATING PESTICIDE-CONTAMINATED SOIL  

EPA Science Inventory

Pesticide contamination results from manufacturing, improper storage, handling, or disposal of pesticides, and from agricultural processes. Since most pesticides are mixtures of different compounds, selecting a remedy for pesticide-contaminated soils can be a complicated process....

123

Soils as a buffer of contaminants in catchments  

NASA Astrophysics Data System (ADS)

Human activities deliver large quantities of contaminants into the environment through atmospheric emissions or direct releases. As many of those contaminants are particle-reactive, they bind strongly to the finest particles or on their organic matter fraction once they deposit onto soils. Contaminants may subsequently migrate in depth of the soil depending on their physico-chemical characteristics. They may also be redistributed along hillslopes in association with particles during soil erosion events and may be subsequently supplied to rivers, preventing to meet the international environmental targets (e.g. in the framework of the EU Water Framework Directive). In regions where soil erosion rates are low to moderate, a large quantity of particle-reactive contaminants may accumulate in soils that constitute a reservoir of pollutants that may be delivered to rivers during decades or centuries. This session will focus on the specific role played by soils as a reservoir of contaminants at the catchment scale. A better understanding of this role and a quantification of the persistence of contaminants in this reservoir will provide crucial insights to guide the implementation of efficient mitigation measures. Contributions to this session may address any aspect of particle-borne contaminant transfer at the catchment scale, with an emphasis on the role played by soils in their storage and transfer. Field-based or modeling studies may focus either on specific pollutants or on a wider range of substances, e.g. metals, radionuclides, organic contaminants. Key themes may include: • Contaminant budget at the hillslope vs. the catchment scales; • Evaluation of the contribution of the regional vs. local contamination sources; • Evaluation of the contaminant removal from soils by degradation vs. soil erosion; • Quantifying the persistence of contaminants in soils; • Discrimination between the legacy and the contemporary supply of contaminants to soils.

Evrard, Olivier

2014-05-01

124

Trench 'Bathtubbing' and Surface Plutonium Contamination at a Legacy Radioactive Waste Site  

PubMed Central

Radioactive waste containing a few grams of plutonium (Pu) was disposed between 1960 and 1968 in trenches at the Little Forest Burial Ground (LFBG), near Sydney, Australia. A water sampling point installed in a former trench has enabled the radionuclide content of trench water and the response of the water level to rainfall to be studied. The trench water contains readily measurable Pu activity (?12 Bq/L of 239+240Pu in 0.45 ?m-filtered water), and there is an associated contamination of Pu in surface soils. The highest 239+240Pu soil activity was 829 Bq/kg in a shallow sample (0–1 cm depth) near the trench sampling point. Away from the trenches, the elevated concentrations of Pu in surface soils extend for tens of meters down-slope. The broader contamination may be partly attributable to dispersion events in the first decade after disposal, after which a layer of soil was added above the trenched area. Since this time, further Pu contamination has occurred near the trench-sampler within this added layer. The water level in the trench-sampler responds quickly to rainfall and intermittently reaches the surface, hence the Pu dispersion is attributed to saturation and overflow of the trenches during extreme rainfall events, referred to as the ‘bathtub’ effect. PMID:24256473

2013-01-01

125

System for the removal of contaminant soil-gas vapors  

DOEpatents

A system extracts contaminated vapors from soil or other subsurface regions by using changes in barometric pressure to operate sensitive check valves that control air entry and removal from wells in the ground. The system creates an efficient subterranean flow of air through a contaminated soil plume and causes final extraction of the contaminants from the soil to ambient air above ground without any external energy sources. 4 figs.

Weidner, J.R.; Downs, W.C.; Kaser, T.G.; Hall, H.J.

1997-12-16

126

System for the removal of contaminant soil-gas vapors  

DOEpatents

A system extracts contaminated vapors from soil or other subsurface regions by using changes in barometric pressure to operate sensitive check valves that control air entry and removal from wells in the ground. The system creates an efficient subterranean flow of air through a contaminated soil plume and causes final extraction of the contaminants from the soil to ambient air above ground without any external energy sources.

Weidner, Jerry R. (Iona, ID); Downs, Wayne C. (Sugar City, ID); Kaser, Timothy G. (Ammon, ID); Hall, H. James (Idaho Falls, ID)

1997-01-01

127

Obsolete Pesticides Pollution and Phytoremediation of Contaminated Soil in Kazakhstan  

Microsoft Academic Search

In Kazakhstan, a deepening ecological crisis has been caused by contamination of the environment with obsolete and expired\\u000a pesticides. Large-scale physical and chemical technologies for managing pesticide-contaminated soils are expensive and unacceptable\\u000a for Kazakhstan because of limited financial resources. Phytoremediation is a promising innovative technology for managing\\u000a pesticide-contaminated soils. Pesticide contamination is common on land surrounding destroyed warehouses that were

A. Nurzhanova; P. Kulakow; E. Rubin; I. Rakhimbayev; A. Sedlovskiy; K. Zhambakin; S. Kalugin; E. Kolysheva; L. Erickson

128

BIOREMEDIATION OF MIXED VAPOR PHASE CONTAMINANTS FROM SOILS AND GROUNDWATER  

EPA Science Inventory

Soil vapor phase contaminants commonly include combinations of chlorinated ethenes and petroleum hydrocarbons. Many chlorinated ethenes and petroleum hydrocarbons are readily degradable by a range of aerobic soil microorganisms, making the use of biological systems for degrading ...

129

Mouse Assay for Determination of Arsenic Bioavailability in Contaminated Soils  

EPA Science Inventory

Background: Accurate assessment of human exposure estimates from arsenic-contaminated soils depends upon estimating arsenic (As) soil bioavailability. Development of bioavailability assays provides data needed for human health risk assessments and supports development and valida...

130

Dioxin contamination in soils of Southern Vietnam.  

PubMed

Dioxin is the common name for polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), and is abbreviated as PCDD/Fs. In the case of Southern Vietnam, is of high concern dioxin contamination in the areas affected by past-use chemical defoliants. Our study related to the zone considered as a "hot spot"--Bien Hoa Airbase and surrounding areas (Bien Hung Lake). Although the war ended over 30 years ago, the adverse effects on this territory still continue. Soil and sediment were selected for our research as they act as a sink for PCDD/Fs. The samples were taken and analyzed in CECOTOX laboratory following certified procedures. The total amounts of PCDD/Fs (2,3,7,8 related congeners) in the samples were converted into WHO-TEQ and compared with standard values proposed by Canadian environmental quality guidelines. The obtained data shows a relatively high risk (up to 20.4 times higher than (probable effect level) PEL value for sediment and 46 times higher than standard value for soil). The research is continuing on the assessment of dioxin transport in food chain. Moreover, considering the obtained data a complete solution should be found urgently to solve the problem of dioxin contamination in the studied areas. PMID:17222446

Mai, Tuan Anh; Doan, Thanh Vu; Tarradellas, Joseph; de Alencastro, Luiz Felippe; Grandjean, Dominique

2007-04-01

131

Radiolytic treatment of dioxin contaminated soils  

NASA Astrophysics Data System (ADS)

Recent work in our laboratory has demonstrated that ?-radiolysis is a feasible method by which 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can be converted to products of negligible toxicity. In the presence of 25% water, 2.5% non-ionic surfactant and at a dose of 800 kGy greater than 98% destruction was achieved in a standard soil artificially contaminated with 100 ppb TCDD. By-product analysis has illustrated that the destruction occurs via step-wise reductive dechlorination producing a suite of lesser chlorinated dioxins. These results in combination with scavenger studies, target theory calculations and yields indicate that direct radiation effects account for the major route of destruction. Radiolysis has also been conducted on a real soil contaminated with TCDD and other chlorinated aromatic compounds verifying the results of model studies. Based on the data of these experiments some designs of batch gamma systems are considered and a discussion of estimated capital and operating costs associated with ?-radiolysis is presented. Given the high costs of the alternatives (i.e. incineration), radiolysis appears to be not only technically feasible, but it may also be economically competitive.

Gray, Kimberly A.; Hilarides, Roger J.

1995-09-01

132

Optimization of Surfactant-Aided Remediation of Industrially Contaminated Soils  

Microsoft Academic Search

Soil matrices contaminated with polycyclic aromatic hydrocarbons (PAHs) abound at the sites of coke-oven gas plants, refineries, and many other major chemical industries. The removal of PAHs from soil using pure water, via soil washing for (ex situ) or soil flushing (in situ), is quite ineffective due to their low solubility and hydrophobicity. However, addition of suitable surfactant(s) has been

MEDHA M. JOSHI; SUNGGYU LEE

1996-01-01

133

Bioremediation of petroleum contaminated soil using vegetation: A microbial study  

Microsoft Academic Search

The degradation of selected petroleum hydrocarbons in the rhizosphere of alfalfa was investigated in a greenhouse experiment. Petroleum contaminated and uncontaminated soils were spiked with 100 ppm of polynuclear aromatic and aliphatic hydrocarbons. Unspiked, uncontaminated soil was used as a control. Microbial counts for soils with and without plants for each soil treatment were performed 4, 8, 16, and 24

Euisang Lee; M. K. Banks

1993-01-01

134

Comprehensive methodology for ecological risk assessment of contaminated soils  

SciTech Connect

Development of a comprehensive methodology for ecological risk assessment and monitoring of contaminated soils is essential to assess the impacts of environmental contaminants on soil community and biologically-mediated processes in soil. The proposed four-step plan involves (1) a thorough survey of the soil community to establish biodiversity and a base-line community structure, (2) toxicity trials on indicator species and whole soil invertebrate communities, (3) laboratory and field tests on indicator processes and (4) the use of statistical and simulation models to ascertain changes in the soil ecosystems. This methodology was used in portions of the US Army`s Aberdeen Proving Ground, Maryland as part of an ecological risk assessment. Previous soil analyses showed extensive surface soil contamination with metals, nitrate and PCBs. Preliminary results from field surveys of soil invertebrate communities showed significant reductions in total abundance of animals, reductions in the abundance of several taxonomic and functional groups of soil invertebrates, and changes in the activity of epigeic arthropods in contaminated areas when compared with the local ``background`` area. Laboratory tests also demonstrated that microbial activity and success of egg hatching of ground beetle Harpalus pensylvanicus were reduced in contaminated soils. These results suggest that impacts to soil ecosystems should be explicitly considered in ecological risk assessment. The proposed comprehensive methodology appears to offer an efficient and potentially cost saving tool for remedial investigations of contaminated sites.

Kuperman, R.G. [Argonne National Lab., IL (United States)

1994-12-31

135

Potential airborne release from soil-working operations in a contaminated area  

SciTech Connect

Experiments were performed to provide an indication of how much material could be made airborne during soil-working operations in a contaminated area. Approximately 50 kg of contaminated soil were collected, dried, and mixed, and particle size distribution and /sup 137/Cs content were characterized. In four experiments performed in a 2 ft x 2 ft wind tunnel at the Radioactive Aerosol Release Test Facility, soil was pumped into an airstream moving at 3.2, 10.4, 15.2, and 20 mph. These experiments were designed to maximize airborne releases by fluidizing the soil as it was pumped into the wind tunnel. Thus the airborne releases should represent upper limit values for soil-working operations. Airborne concentration and particle size samples were collected and all of the material deposited downstream was collected to calculate a mass balance. The fraction airborne was calculated using these measurements.

Sutter, S.L.

1980-08-01

136

Dioxin removal from contaminated soils by ethanol washing.  

PubMed

The aim of this study was to investigate the potential utility of ethanol washing for remediating soils contaminated with polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), as a cost-efficient alternative to conventional remediation methods of PCDD/F-contaminated soils. Initially, screening experiments were performed with a two-level full factorial design to examine the effects of temperature, extraction time and ethanol concentration on the removal efficiency. The screening experiments showed that the ethanol concentration was the most important parameter. In addition, repeated washing cycles considerably improved the results. Ethanol washing conditions were then selected (10 wash cycles with 75% ethanol at 60 degrees C), and applied to four soils with different soil characteristics and contamination levels to test the robustness of the selected method. Treatment efficiencies of 81% and 85% were obtained for a lightly contaminated sandy-silty soil and a highly contaminated clay soil rich in graphite particles, respectively. Even higher treatment efficiencies (> or = 97%) were obtained for two other highly contaminated soils, one of which contained high amounts of organic matter. PCDD/Fs were found to both dissolve in the solvent and migrate into it as species adsorbed to particles. The relative contributions of these mechanisms and the overall efficiency of the removal seem to depend on contaminant concentration, the types of carbon in the soil matrix and the particle size distribution. The study shows that ethanol washing has effective remediation potential for a variety of PCDD/F-contaminated soils. PMID:20399556

Jonsson, Sofia; Lind, Henrik; Lundstedt, Staffan; Haglund, Peter; Tysklind, Mats

2010-07-15

137

Effectiveness of complex fertilizers of new generation on radioactive contaminated lands  

NASA Astrophysics Data System (ADS)

The basic and general remediation principles of agricultural lands affected by technological contamination are presented. One of the perspective method of soil fertility rising is ap-plication of natural clays and minerals. This is the most effective measure on contaminated lands. We can reduce the uptake of 137Cs in 3-5 times because of retention of radionuclides in crystal structures of minerals and its transformation in unapproachable form for plants. Nowdays a special attention pays to sorbents. The stores of natural sorbents (trepel and pa-lygorskit clay) are founded in a grate amount in Kaluga region. A complex sorbent has been developed and on its basis a fundamentally new compound manufactured which combines properties of both sorbent and complex long-acting fertilizer ("Suprodit") that contains NPK (patent on the invention No. 2336257). The base of complex sorbent is SiO2 enriched mineral - trepel. Complex sorbent is a mixture of hydrothermally processed permutite and silicagel with significant sorption properties for radionuclides. This sorbent may be used for fertility rising of the contaminated lands and grain yield, and also for reducing of pollutants uptake. The most effectiveness of "Suprodit" was on fodder lands contaminated with 500-920 kBk137Cs/m2. It has been found that the use of resource-saving technologies with using "Suprodit" increased the yield of barley by 10-40% and the productivity of sowing grasses by 4-5 times. "Suprodit" decreased the concentration of 137Cs in sowing grasses by 1,8-4,0 times. It has been studied the effect of "Suprodit" and industrial fertilizers (NPK and «nitropfoska») on the biological activity of soddy-podzolic soil, contaminated of 137Cs (100 kBk/kg). "Suprodit" increased the CO2 emission rate on radioactively contaminated soil by 1,5 times in comparison with NPK and «nitropfoska», accordingly.

Ratnikov, A. N.; Sanzharova, N. I.; Sviridenko, D. G.; Zhigareva, T. L.

2012-04-01

138

Layer of organic pine forest soil on top of chlorophenol-contaminated mineral soil enhances contaminant degradation.  

PubMed

Chlorophenols, like many other synthetic compounds, are persistent problem in industrial areas. These compounds are easily degraded in certain natural environments where the top soil is organic. Some studies suggest that mineral soil contaminated with organic compounds is rapidly remediated if it is mixed with organic soil. We hypothesized that organic soil with a high degradation capacity even on top of the contaminated mineral soil enhances degradation of recalcitrant chlorophenols in the mineral soil below. We first compared chlorophenol degradation in different soils by spiking pristine and pentachlorophenol-contaminated soils with 2,4,6-trichlorophenol in 10-L buckets. In other experiments, we covered contaminated mineral soil with organic pine forest soil. We also monitored in situ degradation on an old sawmill site where mineral soil was either left intact or covered with organic pine forest soil. 2,4,6-Trichlorophenol was rapidly degraded in organic pine forest soil, but the degradation was slower in other soils. If a thin layer of the pine forest humus was added on top of mineral sawmill soil, the original chlorophenol concentrations (high, ca. 70 ?g g(-1), or moderate, ca. 20 ?g g(-1)) in sawmill soil decreased by >40 % in 24 days. No degradation was noticed if the mineral soil was kept bare or if the covering humus soil layer was sterilized beforehand. Our results suggest that covering mineral soil with an organic soil layer is an efficient way to remediate recalcitrant chlorophenol contamination in mineral soils. The results of the field experiment are promising. PMID:22752813

Sinkkonen, Aki; Kauppi, Sari; Simpanen, Suvi; Rantalainen, Anna-Lea; Strömmer, Rauni; Romantschuk, Martin

2013-03-01

139

Environmental review of options for managing radioactively contaminated carbon steel  

SciTech Connect

The U.S. Department of Energy (DOE) is proposing to develop a strategy for the management of radioactively contaminated carbon steel (RCCS). Currently, most of this material either is placed in special containers and disposed of by shallow land burial in facilities designed for low-level radioactive waste (LLW) or is stored indefinitely pending sufficient funding to support alternative disposition. The growing amount of RCCS with which DOE will have to deal in the foreseeable future, coupled with the continued need to protect the human and natural environment, has led the Department to evaluate other approaches for managing this material. This environmental review (ER) describes the options that could be used for RCCS management and examines the potential environmental consequences of implementing each. Because much of the analysis underlying this document is available from previous studies, wherever possible the ER relies on incorporating the conclusions of those studies as summaries or by reference.

NONE

1996-10-01

140

Bioremediation of oil-contaminated soil — A rate model  

Microsoft Academic Search

Three rate equations, a modified Monod equation and two mass transfer rate equations, were used to calculate the biodegration rate, oxygen transfer rate and oil transfer rate during a bioremediation process of oil-contaminated soil. Based on experimental rate constants, these three rates were calculated and compared. It was found the bioremediation rate of oil-contaminated soil could be controlled by the

K. Y. Li; Yuebo Zhang; Tian Xu

1995-01-01

141

Rhizosphere Microbial Characterization in Petroleum-Contaminated Soil  

Microsoft Academic Search

Contamination of soil with petroleum compounds is of concern worldwide. Although there are a variety of physical and chemical technologies available to remediate petroleum waste sites, biological methods are often used due to lower cost and public acceptance. Growth and enhanced activity of microbial communities in contaminated soil is a key factor for the success of bioremediation. Establishing vegetation in

M. Katherine Banks; Hadessa Mallede; Karrie Rathbone

2003-01-01

142

Chemical methods and phytoremediation of soil contaminated with heavy metals  

Microsoft Academic Search

The effects of chemical amendments (calcium carbonate (CC), steel sludge (SS) and furnace slag (FS)) on the growth and uptake of cadmium (Cd) by wetland rice, Chinese cabbage and wheat grown in a red soil contaminated with Cd were investigated using a pot experiment. The phytoremediation of heavy metal contaminated soil with vetiver grass was also studied in a field

H. M Chen; C. R Zheng; C Tu; Z. G Shen

2000-01-01

143

Cadmium Removal From Contaminated Soil by Thermally Responsive Elastin  

E-print Network

ARTICLE Cadmium Removal From Contaminated Soil by Thermally Responsive Elastin (ELPEC20: Cadmium contamination of soil is a major concern in the biosphere. Beyond the suite of available phy- sico-chemical treatment methods, green and more efficient technologies are desired to reduce cadmium and other heavy metal

Chen, Wilfred

144

BIOAVAILABILITY OF METALS IN CONTAMINATED SOIL AND DUST  

EPA Science Inventory

Due to widespread metal contamination, it is necessary to characterize soils suspected of metal contamination and determine if the metal levels in these soils pose a hazard. Metal toxicity is often not directly related to the total concentration of metals present due to a numb...

145

Radioactive contamination of fishes in lake and streams impacted by the Fukushima nuclear power plant accident.  

PubMed

The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in March 2011 emitted radioactive substances into the environment, contaminating a wide array of organisms including fishes. We found higher concentrations of radioactive cesium ((137)Cs) in brown trout (Salmo trutta) than in rainbow trout (Oncorhynchus nerka), and (137)Cs concentrations in brown trout were higher in a lake than in a stream. Our analyses indicated that these differences were primarily due to differences in diet, but that habitat also had an effect. Radiocesium concentrations ((137)Cs) in stream charr (Salvelinus leucomaenis) were higher in regions with more concentrated aerial activity and in older fish. These results were also attributed to dietary and habitat differences. Preserving uncontaminated areas by remediating soils and releasing uncontaminated fish would help restore this popular fishing area but would require a significant effort, followed by a waiting period to allow activity concentrations to fall below the threshold limits for consumption. PMID:24657366

Yoshimura, Mayumi; Yokoduka, Tetsuya

2014-06-01

146

Determination of technetium-99 in soils and radioactive wastes using ICP-MS  

Microsoft Academic Search

Three methods have been used for the determination of 99Tc in soils and solid radioactive wastes using 99mTc as a yield monitor. In the method one and three the samples were leached in low concentrated nitric and sulphuric acid.\\u000a Many contaminants were then co-precipitated with Fe(OH)3 in alkali media and Tc in the supernatant was separated using anion-exchange extraction chromatography.

A. Bartošová; P. Rajec; A. Klimeková

2006-01-01

147

In Situ Evaluation of Contaminant Immobilization in Soil  

E-print Network

• Remediation strategies focused on contaminant immobilization must demonstrate: ? Decreased soluble contaminant. ? Increased contaminant in poorly soluble phase. ? Evidence for long-term stability. • There is a need for low-cost, nondestructive techniques to evaluate the above. • Polymer-encapsulated soils (PELCAPS; Fig. 1) were leached continuously in surface and groundwaters at two field sites. • Contaminant leaching behavior was well-described by a diffusion equation that enabled the quantitative estimation of contaminant mobility under actual site geochemical conditions (Fig. 2). • This proof-of-principle study established the baseline feasibility of a generic nondestructive in situ assay technique for quantifying immobilized contaminants on soils and sediments using permeable environmental leaching capsules. • Convenient test for large numbers of soils and soil treatments.

Contacts Brian Spalding; Scott Brooks; Sponsor Doe/ober

148

Vapor stripping of VOC-contaminated clay soils  

SciTech Connect

Vapor stripping is a treatment process in which volatile organic contaminants (VOCs) are removed from contaminated soil by high-pressure aeration. This technology is potentially applicable to low-permeability soils when coupled with in situ soil mixing. A laboratory evaluation of in situ vapor stripping was conducted for TCE-contaminated deposits ({gt}80% silt and clay, and hydraulic conductivity {le}10{sup -6}cm/sec) underlying a land disposal site located at a DOE facility. Intact soil cores taken from contaminated areas and re-packed soil cores spiked with TCE were treated in an apparatus that simulated the vapor stripping process. Removal efficiencies calculated from pre- and posttreatment samples were predominately greater than 85%. In some of the spiked cores, soil samples were taken during treatment to establish removal efficiency as a function of treatment time.

West, O.R.; Siegrist, R.L.; Lucero, A.J.; Jennings, H.L. [Oak Ridge National Lab., TN (United States); Schmunk, S.W. [Michigan Technological Univ., Houghton, MI (United States)

1993-06-01

149

Current methods for evaluating the bioavailability of chemicals from contaminated soils using soil invertebrates  

SciTech Connect

Contaminated soils are an extremely complex, variable matrix where many modifying factors of toxicity (e.g., particle size, organic matter content) alter the availability of chemicals to biota. Although many methods have been standardized for assessing the toxicity of contaminated soils to invertebrates and plants, few studies have actually addressed the issue of contaminant bioavailability from soils. Since bioavailability is a measure of uptake of contaminants from the soil by living organisms, one approach to determining bioavailability is to measure residues of contaminants in biota. Body residues related to a specific lethal or sublethal toxicity endpoint offer the unique opportunity to relate bioavailability to biological response. This paper will present an overview of the use of body residues in assessing the bioavailability of soil contaminants by earthworms and soil arthropods. The applications of body residues in the development of soil quality guidelines will also be discussed.

Lanno, R.P. [Univ. of Waterloo, Ontario (Canada). Dept. of Biology

1995-12-31

150

40 CFR 267.116 - What must I do with contaminated equipment, structure, and soils?  

Code of Federal Regulations, 2013 CFR

...contaminated equipment, structure, and soils? 267.116 Section 267.116 Protection...contaminated equipment, structure, and soils? You must properly dispose of or decontaminate...contaminated equipment, structures, and soils during the partial and final closure...

2013-07-01

151

40 CFR 267.116 - What must I do with contaminated equipment, structure, and soils?  

...contaminated equipment, structure, and soils? 267.116 Section 267.116 Protection...contaminated equipment, structure, and soils? You must properly dispose of or decontaminate...contaminated equipment, structures, and soils during the partial and final closure...

2014-07-01

152

40 CFR 267.116 - What must I do with contaminated equipment, structure, and soils?  

Code of Federal Regulations, 2011 CFR

...contaminated equipment, structure, and soils? 267.116 Section 267.116 Protection...contaminated equipment, structure, and soils? You must properly dispose of or decontaminate...contaminated equipment, structures, and soils during the partial and final closure...

2011-07-01

153

40 CFR 267.116 - What must I do with contaminated equipment, structure, and soils?  

Code of Federal Regulations, 2012 CFR

...contaminated equipment, structure, and soils? 267.116 Section 267.116 Protection...contaminated equipment, structure, and soils? You must properly dispose of or decontaminate...contaminated equipment, structures, and soils during the partial and final closure...

2012-07-01

154

40 CFR 267.116 - What must I do with contaminated equipment, structure, and soils?  

Code of Federal Regulations, 2010 CFR

...contaminated equipment, structure, and soils? 267.116 Section 267.116 Protection...contaminated equipment, structure, and soils? You must properly dispose of or decontaminate...contaminated equipment, structures, and soils during the partial and final closure...

2010-07-01

155

Methodology for using contaminated soil leachability testing to determine soil cleanup levels at contaminated petroleum underground storage tank (UST) sites  

Microsoft Academic Search

The costs of environmental remediation at leaking petroleum underground storage tank (UST) sites are influenced significantly by soil cleanup levels. The use of conservative generic soil cleanup levels may be inappropriate at some sites contaminated by leaking petroleum USTs. At many contaminated sites, a primary objective of site remediation is long?term protection of water resources (e.g., groundwater) from pollution. Leaching

John R. Odermatt; John A. Menatti

1996-01-01

156

Biological Treatment of Petroleum in Radiologically Contaminated Soil  

Microsoft Academic Search

This chapter describes ex situ bioremediation of the petroleum portion of radiologically co-contaminated soils using microorganisms isolated from a waste site and innovative bioreactor technology. Microorganisms first isolated and screened in the laboratory for bioremediation of petroleum were eventually used to treat soils in a bioreactor. The bioreactor treated soils contaminated with over 20,000 mg\\/kg total petroleum hydrocarbon and reduced

2005-01-01

157

Remediation of petroleum contaminated soils through composting and rhizosphere degradation  

Microsoft Academic Search

Composting along with rhizodegradation was used to remediate petroleum-contaminated soils in the Yellow River Delta, China. The average concentration of total petroleum hydrocarbons (TPH) in these soils was reduced from 7900–17,900mgkg?1 to 1400–3700mgkg?1 after field composting. The best volume ratio of amendment to contaminated soil was 2\\/1 and the best C\\/N ratio was 15\\/1. After composting, four local dominant plant

Zhenyu Wang; Ying Xu; Jian Zhao; Fengmin Li; Dongmei Gao; Baoshan Xing

2011-01-01

158

Mechanochemical remediation of heavy metals contaminated soils: Modelling and experiments  

Microsoft Academic Search

The use of mechanochemistry for the remediation of heavy metals contaminated soils is investigated. Specifically, synthetic sandy soils contaminated by Cd(II), Pb(II) and Zn(II) are prepared. The degree of metal immobilization is evaluated after the soil is subjected to mechanical treatment by analyzing the leachable fraction of heavy metals obtained through the “synthetic precipitation leaching procedure (SPLP)”. For the case

Alessandro Concas; Selena Montinaro; Massimo Pisu; Giacomo Cao

2007-01-01

159

Comparison of forest soils and waste-contaminated soils as sources of polysaccharide-degrading microbes  

Microsoft Academic Search

Objective: This study was conducted to determine the suitable soil types that can be used as sources of polysaccharide-degrading microbes. A comparison was done of the potential of isolating such microbes from non-polluted areas (forest soils) and waste-contaminated soils. Methodology and Results: Waste-contaminated soils have more isolates producing polysaccharide-degrading enzymes (polysaccharases) than forest soils. In vitro plate screening using dye-labeled

Ting ASY; Chan HY; Jalan Genting Kelang

2008-01-01

160

Urban community gardeners' knowledge and perceptions of soil contaminant risks.  

PubMed

Although urban community gardening can offer health, social, environmental, and economic benefits, these benefits must be weighed against the potential health risks stemming from exposure to contaminants such as heavy metals and organic chemicals that may be present in urban soils. Individuals who garden at or eat food grown in contaminated urban garden sites may be at risk of exposure to such contaminants. Gardeners may be unaware of these risks and how to manage them. We used a mixed quantitative/qualitative research approach to characterize urban community gardeners' knowledge and perceptions of risks related to soil contaminant exposure. We conducted surveys with 70 gardeners from 15 community gardens in Baltimore, Maryland, and semi-structured interviews with 18 key informants knowledgeable about community gardening and soil contamination in Baltimore. We identified a range of factors, challenges, and needs related to Baltimore community gardeners' perceptions of risk related to soil contamination, including low levels of concern and inconsistent levels of knowledge about heavy metal and organic chemical contaminants, barriers to investigating a garden site's history and conducting soil tests, limited knowledge of best practices for reducing exposure, and a need for clear and concise information on how best to prevent and manage soil contamination. Key informants discussed various strategies for developing and disseminating educational materials to gardeners. For some challenges, such as barriers to conducting site history and soil tests, some informants recommended city-wide interventions that bypass the need for gardener knowledge altogether. PMID:24516570

Kim, Brent F; Poulsen, Melissa N; Margulies, Jared D; Dix, Katie L; Palmer, Anne M; Nachman, Keeve E

2014-01-01

161

Evaluation of TENORMs field measurement with actual activity concentration in contaminated soil matrices.  

PubMed

The occurrence of technologically enhanced naturally occurring radioactive materials (TENORMs) concentrated through anthropogenic processes in contaminated soils at oil and gas facilities represent one of the most challenging issues facing the Canadian and US oil and gas industry today. Natural occurring radioactivity materials (NORMs) field survey techniques are widely used as a rapid and cost-effective method for ascertaining NORMs risks associated with contaminated soils and waste matrices as well other components comprising the environment. Because of potentially significant liability issues with Norms if not properly managed, the development of quantitative relationships between TENORMs field measurement techniques and laboratory analysis present a practical approach in facilitating the interim safe decision process since laboratory results can take days. The primary objective of this study was to evaluate the relationships between direct measurements of field radioactivity and various laboratory batch techniques using data collection technologies for NORM and actual laboratory radioactivity concentrations. The significance of selected soil characteristics that may improve or confound these relationships in the formulation of empirical models was also achieved as an objective. The soil samples used in this study were collected from 4 different locations in western Canada and represented a wide range in terms of their selected chemical and physical properties. Multiple regression analyses for both field and batch data showed a high level of correlation between radionuclides Ra-226 and Ra-228 as a function of data collection technologies and relevant soil parameters. All R2 values for the empirical models were greater than 0.80 and significant at P<0.05. The creation of these empirical models could be valuable in improving predictability of radium contamination in soils and therefore, reduce analytical costs as well as environmental liabilities. PMID:17849307

Saint-Fort, Roger; Alboiu, Mirtyll; Hettiaratchi, Patrick

2007-09-01

162

Remediation of contaminated soils and sludges by green plants  

SciTech Connect

The potential of green plants to remove, contain, or render harmless contaminants in soils and sludges is actively being explored in an increasing number of laboratories throughout the world. This approach, which has been termed phytoremediation, exploits plants, soil amendments, and plant-associated microbiota to remediate contaminated soils. As an in situ stabilization technique, soil amendment with fertilizers, biosolids, or certain industrial by-products alters the chemical and physical nature of the contaminant in the soil matrix, thus reducing its available to biological processes. The site is then vegetated with plants that can (1) grow in the resulting soil matrix; (2) reduce leaching through the soil profile by absorbing, sequestering, or degrading residual contaminants in the soil solution; and (3) minimize wind and rain erosion. The process is known as phytostabilization, or simply site stabilization, and borrows heavily on mine reclamation techniques. As a site decontamination technique, the soil is treated to increase the availability of the contaminant to biological processes and then planted with plants that (1) accumulate the contaminant and are harvested for further pollutant destruction, sequestration, or reclamation or (2) use plant or plant-associated microbial processes to destroy the pollutant in situ.

Cunningham, S.D.; Berti, W.R.; Huang, J.W. [DuPont Co., Newark, DE (United States)

1995-12-31

163

Apparatus for treatment of soils contaminated with organic pollutants  

DOEpatents

An apparatus for treating soil contaminated by organic compounds wherein an ozone containing gas is treated with acid to increase the stability of the ozone in the soil environment and the treated ozone applied to the contaminated soil in a manner adapted to decompose the organic compounds; one embodiment of the apparatus comprises a means to supply ozone as a gas-ozone mixture, a stability means to treat ozone obtained from the supply and distribution means to apply the stabilized gas-ozone to soil. The soil may be treated in situ or may be removed for treatment and refilled.

Wickramanayake, Godage B. (Columbus, OH)

1993-01-01

164

Effects of electrokinetic treatment of a heavy metal contaminated soil on soil enzyme activities  

Microsoft Academic Search

There is a growing concern on the potential application of a direct current (DC) electric field to soil for removing contaminants, but little is known about its impact on soil enzyme activities. This study investigated the change of enzyme activities of a heavy metal contaminated soil before and after electrokinetic (EK) treatments at lab-scale and the mechanisms of EK treatment

Long Cang; Dong-Mei Zhou; Quan-Ying Wang; Dan-Ya Wu

2009-01-01

165

COLUMN VAPOR EXTRACTION EXPERIMENTS ON GASOLINE CONTAMINATED SOIL  

EPA Science Inventory

Soil vapor extraction (SVE) is a technique that is used to remove volatile organic compounds from unsaturated soils. ir is pumped from the contaminated area and the chemicals are removed from the resulting vapor stream. n this work laboratory, soil column experiments were conduct...

166

Restoration of Petroleum-Contaminated Soil Using Phased Bioremediation  

Microsoft Academic Search

A conceptual approach is presented for the restoration of petroleum-contaminated sites by combining bioremediation with revegetation using native plants. Phased bioremediation includes active and passive treatment options for soil containing greater than 1% total petroleum hydrocarbons (TPHs). Phase I is used when initial soil TPH exceeds 1%. Phase I utilizes either active land treatment, with regular soil tillage, or passive

James L Brown; Royal J Nadeau

2002-01-01

167

Relative bioavailability of arsenic contaminated soils in a mouse model  

EPA Science Inventory

Exposure to As contaminated soils compels extensive soil cleanups so that human health risks are minimized. In order to improve exposure estimates and potentially reduce remediation costs, determination of the bioavailability of As in soils is needed. The objective of this study ...

168

Study on magnetic separation for decontamination of cesium contaminated soil by using superconducting magnet  

NASA Astrophysics Data System (ADS)

The accident of Fukushima Daiichi nuclear power plant caused the diffusion of radioactive cesium over the wide area. We examined the possibility of applying magnetic separation method using the superconducting magnet, which can process a large amount of the soil in high speed, to the soil decontamination and volume reduction of the radioactive cesium contaminated soil. Clay minerals are classified as 2:1 and 1:1 types by the difference of their layer structures, and these types of minerals are respectively paramagnetic and diamagnetic including some exception. It is known that most of the radioactive cesium is strongly adsorbed on the clay, especially on 2:1 type clay minerals. It is expected that the method which can separate only 2:1 type clay minerals selectively from the mixture clay minerals can enormously contribute to the volume reduction of the contaminated soil. In this study, the components in the clay before and after separation were evaluated to estimate the magnetic separation efficiency by using X-ray diffraction. From the results, the decontamination efficiency and the volume reduction ratio were estimated in order to examine the appropriate separation conditions for the practical decontamination of the soil.

Igarashi, Susumu; Nomura, Naoki; Mishima, Fumihito; Akiyama, Yoko

2014-09-01

169

Reducing logistical barriers to radioactive soil remediation after the Fukushima No. 1 nuclear power plant accident  

NASA Astrophysics Data System (ADS)

We present an updated assessment of soil contamination due to the nuclear accident at the Fukushima No. 1 nuclear power plant on 11 March 2011. A safe limit for the spatial dose rate (micro-Sv/h) of gamma rays from 134,137Cs has been established in this work. Based on this value, the highly contaminated region within Fukushima Prefecture that must be decontaminated could be defined. Moreover, a conceptual model for the chemical speciation that occurred during the accident has been delineated. The compound model Cs2CO3 was found to be meaningful and practical (non-radioactive) to simulate contamination in our decontamination experiments. Finally, we explain the mechanism of action of our soil remediation technique, which effectively reduces the total volume of contaminated soil by isolating the highly Cs-adsorptive clay fraction. The adsorption of non-radioactive Cs atoms on clay particles with diameters <25 ?m were analyzed using micro-particle-induced X-ray emission (PIXE).

Ishii, K.; Terakawa, A.; Matsuyama, S.; Kikuchi, Y.; Fujishiro, F.; Ishizaki, A.; Osada, N.; Arai, H.; Sugai, H.; Takahashi, H.; Nagakubo, K.; Sakurada, T.; Yamazaki, H.; Kim, S.

2014-01-01

170

Evaluation and ranking of restoration strategies for radioactively contaminated sites.  

PubMed

An international project, whose aim was the development of a transparent and robust method for evaluating and ranking restoration strategies for radioactively contaminated sites (RESTRAT), was carried out under the Fourth Framework of the Nuclear Fission Safety Programme of the EU. The evaluation and ranking procedure used was based on the principles of justification and optimisation for radiation protection. A multi-attribute utility analysis was applied to allow for the inclusion of radiological health effects, economic costs and social factors. Values of these attributes were converted into utility values by applying linear utility functions and weighting factors, derived from scaling constants and expert judgement. The uncertainties and variabilities associated with these utility functions and weighting factors were dealt with by a probabilistic approach which utilised a Latin Hypercube Sampling technique. Potentially relevant restoration techniques were identified and their characteristics determined through a literature review. The methodology developed by this project has been illustrated by application to representative examples of different categories of contaminated sites; a waste disposal site, a uranium tailing site and a contaminated freshwater river. PMID:11446122

Zeevaert, T; Bousher, A; Brendler, V; Jensen, P H; Nordlinder, S

2001-01-01

171

Soil and Water Science Department University of Florida Field applications of phosphate rock for remediation of metal contaminated soils  

E-print Network

for remediation of metal contaminated soils Ma, L. Q., W. Harris, and R.H. Stamps 4/2002-3/2006 Lead and arsenic, and the extent and severeness of the contamination. Successful remediation of metal-contaminated soils would in immobilizing lead in contaminated soils; 2) explore the feasibility of using PR to remediate lead contaminated

Ma, Lena

172

Mycobacterium Diversity and Pyrene Mineralization in Petroleum-Contaminated Soils  

PubMed Central

Degradative strains of fast-growing Mycobacterium spp. are commonly isolated from polycyclic aromatic hydrocarbon (PAH)-contaminated soils. Little is known, however, about the ecology and diversity of indigenous populations of these fast-growing mycobacteria in contaminated environments. In the present study 16S rRNA genes were PCR amplified using Mycobacterium-specific primers and separated by temperature gradient gel electrophoresis (TGGE), and prominent bands were sequenced to compare the indigenous Mycobacterium community structures in four pairs of soil samples taken from heavily contaminated and less contaminated areas at four different sites. Overall, TGGE profiles obtained from heavily contaminated soils were less diverse than those from less contaminated soils. This decrease in diversity may be due to toxicity, since significantly fewer Mycobacterium phylotypes were detected in soils determined to be toxic by the Microtox assay than in nontoxic soils. Sequencing and phylogenetic analysis of prominent TGGE bands indicated that novel strains dominated the soil Mycobacterium community. Mineralization studies using [14C]pyrene added to four petroleum-contaminated soils, with and without the addition of the known pyrene degrader Mycobacterium sp. strain RJGII-135, indicated that inoculation increased the level of degradation in three of the four soils. Mineralization results obtained from a sterilized soil inoculated with strain RJGII-135 suggested that competition with indigenous microorganisms may be a significant factor affecting biodegradation of PAHs. Pyrene-amended soils, with and without inoculation with strain RJGII-135, experienced both increases and decreases in the population sizes of the inoculated strain and indigenous Mycobacterium populations during incubation. PMID:11319104

Cheung, Pui-Yi; Kinkle, Brian K.

2001-01-01

173

Phytoremediation of oil-sludge-contaminated soil.  

PubMed

The aim of this research was to select plant species that could be effective in the phytoremediation ofa former oil-sludge pit. Seven crop plants (Triticum aestivum L., Secale cereale L., Avena sativa L., Hordeum vulgare, Sorghum bicolor L Moench, Panicum miliaceum L, and Zea mays L.),five wild grasses (Lolium perenne L., Bromopsis inermis, Agropyron cristatum L., Agropyrum tenerum L., and Festuca pratensis Huds.), and three legumes (Medicago sativa L., Trifolium pratense L., and Onobrychis antasiatica Khin.) were screened for phytotoxicity, including the assessment of germination, shoot biomass, and root biomass, in a pot experiment. The estimation of oil-sludge degradation in the root zone of the tested plants showed that rye accelerated cleanup most effectively, degrading all of the main contaminant fractions in the oil sludge by a total of 52%. Although alfalfa had a lower phytoremediation potential than did rye, it maintained large numbers of soil microorganisms, including polycyclic aromatic hydrocarbon degraders, in its rhizosphere. Rye and alfalfa were chosen for a large-scale study to remediate an oil-sludge pit on the grounds of a petroleum refinery. Remediation monitoring confirmed the effectiveness of rye: the oil-sludge content decreased consistently for 3 years and remained low in comparison with the results from other plant species. PMID:19260228

Muratova, A Y; Dmitrieva, T V; Panchenko, L V; Turkovskaya, O V

2008-01-01

174

Radioactive contamination of the environment and the possible consequences.  

PubMed

To find the optimum solution to the problem of how to protect the environment from pollution by industrial waste, it is necessary, first and foremost, to obtain information on the existing levels of various forms of pollution and the damage caused by them. In this review data are given on all the main sources of contamination of the environment by radioactive substances. The pathways by which these substances reach and affect the human body are discussed, the doses incurred are characterized and the possible consequences of existing levels of exposure are assessed in the light of the latest data on the dose-effect relationship. The wisdom of treating the evaluation of radiation hazards arising from the use of atomic energy not in isolation but as part of a whole complex of ecological factors - including the use of conventional fuels for power generation and transport - is duly noted. PMID:1173780

Knizhnikov, V A; Barkhudarov, R M

1975-06-01

175

Laboratory and greenhouse assessment of phytoremediation of petroleum contaminated soils  

SciTech Connect

Phytoremediation of soils contaminated with petroleum and associated priority pollutants was evaluated in greenhouse and laboratory experiments. Mineralization of several PAHs was measured in rhizosphere soil, non-rhizosphere soil, and sterile soil amended with simulated root exudates. The least amount of mineralization was observed in sterile soil, but there were no differences among all other soils. Mineralization of 14 C-benzo[a]pyrene was determined in chambers to determine the effects of tall fescue on dissipation of this compound. After 180 days, the soils with fescue had more than twice the mineralization than soils without plants. In the soils with plants, evolution of 14CO2 from the soil was five times greater than from the plant biomass. These experiments demonstrate that the presence of plants is a necessary part of the phytoremediation process. There appears to be no residual rhizosphere effect, and the simple exudation of organic compounds does not mimic fully the presence of roots.

Banks, M.K.; Schwab, A.P.; Wang, X. [Kansas State Univ., Manhattan, KS (United States)

1996-12-31

176

Effects of soil organic matter and ageing on remediation of diesel-contaminated soil  

Microsoft Academic Search

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,

Pao-Wen Grace Liu; Sih-Yu Wang; Shen-Gzhi Huang; Ming-Zhi Wang

2012-01-01

177

Radioactive waste disposal implications of extending Part IIA of the Environmental Protection Act to cover radioactively contaminated land  

Microsoft Academic Search

A short study has been carried out of the potential radioactive waste disposal issues associated with the proposed extension of Part IIA of the Environmental Protection Act 1990 to include radioactively contaminated land, where there is no other suitable existing legislation. It was found that there is likely to be an availability problem with respect to disposal at landfills of

D. J. Nancarrow; M. M. White

2004-01-01

178

Traitement par fusion des dechets metalliques contamines faible activite. (Fusion process for metallic wastes slightly contaminated by radioactive substances).  

National Technical Information Service (NTIS)

To ameliorate the management of metallic wastes lightly contaminated by radioactive substances and coming from nuclear installations dismantling, the Radiation Protection Service of Saclay has undertaken the study of fusion process for these wastes. After...

C. Doucet

1988-01-01

179

Assessing soil and groundwater contamination in a metropolitan redevelopment project.  

PubMed

The purpose of this study was to assess contaminated soil and groundwater for the urban redevelopment of a rapid transit railway and a new mega-shopping area. Contaminated soil and groundwater may interfere with the progress of this project, and residents and shoppers may be exposed to human health risks. The study area has been remediated after application of first remediation technologies. Of the entire area, several sites were still contaminated by waste materials and petroleum. For zinc (Zn) contamination, high Zn concentrations were detected because waste materials were disposed in the entire area. For petroleum contamination, high total petroleum hydrocarbon (TPH) and hydrocarbon degrading microbe concentrations were observed at the depth of 7 m because the underground petroleum storage tank had previously been located at this site. Correlation results suggest that TPH (soil) concentration is still related with TPH (groundwater) concentration. The relationship is taken into account in the Spearman coefficient (?). PMID:23307052

Yun, Junki; Lee, Ju Young; Khim, Jeehyeong; Ji, Won Hyun

2013-08-01

180

Evaluation of extraction procedures for removing lead from contaminated soil.  

PubMed

Soil extraction of lead contaminated soil collected from sites near an abandoned battery recycling and secondary lead-smelting factory was investigated for potential use in decontaminating soil at the sites. A fractionation study was conducted to elucidate soil retention mechanism for Pb at the site. Three soil pits were selected from an area surrounding the factory based on level of Pb contamination. Soil samples were collected from each pit in two layers: surface soil and subsoil (0-15 cm and 15-30 cm). Soil physical analysis showed that the soil texture was sandy loam and sandy clay loam with clay content between 11-21%. Soil pH was strongly acid to moderately acid (pH 4.8-5.9). Pb levels in the surface soil were 1620 and 153 mg kg(-1) (air-dried basis) respectively for heavily and slightly contaminated soil. A reference soil site contained 15 mg kg(-1) of Pb. Partitioning studies indicated that more than 90% of total Pb in the soil existed in three primary fractions: exchangeable, carbonate, and Fe-Mn oxide. This suggested that Pb sources entering the soil from the Pb factory remained in relatively weakly bound forms, which are mobile and have potentially biological availability. Mobility of Pb as in the soil assessed by mobility factor (MF) was as high as 75% indicating a high potential of Pb remobilization. Due to high mobility, the Pb would be amendable to remediation or removal by soil extraction procedures. To determine if such weekly bound Pb could be easily removed, both soil washing (ex situ) and soil flushing (in situ) techniques were evaluated for potential Pb remediation procedure. Particle size separation of soil into coarse (2.0-0.25 mm), medium (0.25-0.15 mm), and fine size (<0.15 mm) was conducted before initiating soil washing for comparing Pb removal efficiency in these fractions with the indigenous soil fraction. Using EDTA (2:1 mole to Pb) as a washing solution up to 85-95% of Pb was removed under the optimum conditions (retention time = 60 min), and liquid to solid ratio (L/S) at 5:1 for coarse fraction and 10:1 for smaller fraction. Pb could be removed from contaminated soil using EDTA extraction; however, the efficiency was higher in the coarse texture soil fraction. As a result particle size separation is recommended before application of the soil washing procedure. For smaller soil particle size fraction a series of extraction was needed for obtaining an adequate extraction efficiency. Three solvents tested as flushing solution showed 85, 84, and 74% of Pb was removed by EDTA (2:1 mole to Pb), 1M HNO3, and 0.2 M ammonium citrate, respectively after flushing with 20 pore volumes. The capacity of the three flushing solutions to remove Pb from the contaminated soil were ranked in the order: EDTA approximately 1 M HNO3 > 0.2 N ammonium citrate. However, in highly contaminated soil all solvent extract required several Pb leaching cycles. The flushing process using 1 M HNO3 increased soil acidity to extreme acid conditions (pH 2.0) resulting in adverse effects to physicochemical properties of the treated soil. In general, results showed three factors influenced Pb removal by the extraction techniques: (i) initial Pb concentrations, (ii) Pb partitioning within soil, and (iii) particle size of soil matrix. PMID:15717783

Tawinteung, Nukoon; Parkpian, Preeda; DeLaune, R D; Jugsujinda, Aroon

2005-01-01

181

Decreasing the contamination and toxicity of a heavily contaminated soil by in situ bioremediation  

NASA Astrophysics Data System (ADS)

An experimental plot of 140 m2 consisting of acidic soil heavily contaminated with uranium, non-ferrous metals (mainly Cu, Zn and Cd) and arsenic was treated in situ under real field conditions using the activity of the indigenous soil microflora. This activity was enhanced by suitable changes of some essential environmental factors such as pH and water, oxygen and nutrient contents of the soil. The treatment was connected with solubilization and removal of contaminants from the top soil layers (horizon A) due to the joint action of the soil microorganisms (mainly acidophilic chemolithotrophic bacteria) and leach solutions (diluted sulphuric acid). The dissolved contaminants were transferred to the soil horizon B and were removed from the soil profile through a system of drainage collecting pipes. The contaminated soil effluents were treated by means of a multi-component passive system consisting of an anoxic alkalizing drain, a permeable reactive multibarrier and a rock filter. The contamination and toxicity of the soil were regularly tested during the cleaning procedure and were considerably decreased at the end of the treatment.

Groudev, Stoyan; Georgiev, Plamen; Spasova, Irena; Nikolova, Marina

2013-04-01

182

Ecological effects of soil contamination at Aberdeen Proving Ground, Maryland  

SciTech Connect

Assessment of the ecological condition of contaminated soil was conducted in portions of the U.S. Army's Aberdeen Proving Ground, Maryland as part of an ecological risk assessment. This area is covered by open fields, woods and nontidal marshes. Chemicals disposed of in open burning pits included methylphosphonothioic acid, dichlorodiethyl sulfide, and titanium tetrachloride and sulfur trioxide/chlorosulfonic acid. Previous soil analysis showed extensive surface soil contamination with metals, nitrate, PCBs and pesticides. This assessment included characterizing soil biota, biologically-mediated processes in soil and aboveground biomass. Field surveys of the soil invertebrate communities showed significant reductions in the total abundance of animals, reductions in the abundance of several taxonomic and functional groups of soil invertebrates, and changes in the activity of epigeic arthropods in contaminated areas when compared with the local [open quotes]background[close quotes] area. Laboratory toxicity tests also demonstrated that microbial activity and success of egg hatching of ground beetle Harpalus pensylvanicus were reduced in contaminated soils. These results suggest that impacts to soil ecosystems should be explicitly considered in ecological risk assessment.

Kuperman, R.G.; Dunn, C.P. (Argonne National Laboratory, IL (United States))

1994-06-01

183

Geochemical information for sites contaminated with low-level radioactive wastes. III. Weldon Spring Storage Site  

SciTech Connect

The Weldon Spring Storage Site (WSSS), which includes both the chemical site and the quarry, became radioactively contaminated as the result of wastes that were being stored from operations to recover uranium from pitchblende ores in the 1940s and 1950s. The US Department of Energy (DOE) is considering various remedial action options for the WSSS. This report describes the results of geochemical investigations carried out at Oak Ridge National Laboratory (ORNL) to support these activities and to help quantify various remedial action options. Soil and groundwater samples were characterized, and uranium and radium sorption ratios were measured in site soil/groundwater systems by batch contact methodology. Soil samples from various locations around the raffinate pits were found to contain major amounts of silica, along with illite as the primary clay constituent. Particle sizes of the five soil samples were variable (50% distribution point ranging from 12 to 81 ..mu..m); the surface areas varied from 13 to 62 m/sup 2//g. Elemental analysis of the samples showed them to be typical of sandy clay and silty clay soils. Groundwater samples included solution from Pit 3 and well water from Well D. Anion analyses showed significant concentrations of sulfate and nitrate (>350 and >7000 mg/L, respectively) in the solution from Pit 3. These anions were also present in the well water, but in lower concentrations. Uranium sorption ratios for four of the soil samples contacted with the solution from Pit 3 were moderate to high (approx. 300 to approx. 1000 mL/g). The fifth sample had a ratio of only 12 mL/g. Radium sorption ratios for the five samples were moderate to high (approx. 600 to approx. 1000 mL/g). These values indicate that soil at the WSSS may show favorable retardation of uranium and radium in the groundwater. 13 references, 13 figures, 10 tables.

Seeley, F.G.; Kelmers, A.D.

1985-02-01

184

Biokinetic parameter estimation for ISB of PAH-contaminated soil  

SciTech Connect

In situ bioremediation (ISB) has been shown to be an effective and cost-efficient method for remediating contaminated ground water and soil. One of the major disadvantages associated with this process is the lack of available kinetic information. The viability of respirometry to determine the relevant biokinetic parameters for degradation of contaminants in groundwater has been proven; however, little work has been done using soil systems. This work investigated the applicability of using respirometer data to determine the biokinetic parameters for soil systems. The specific soil investigated was contaminated with polycyclic aromatic hydrocarbons (PAHs), which contain 16 EPA priority pollutants. The work also investigated a logarithmic growth and modified Lineweaver-Burke approach for experimentally determining the maximum specific growth rate from batch degradation data. As expected, this research concluded that determining all biokinetic parameters from respirometer data was not a viable method for soil systems. Obtaining the maximum specific growth rate from batch degradation data provided more accurate results.

Smith, K.; Cutright, T.; Qammar, H.

2000-04-01

185

Remediation of sandy soils contaminated with hydrocarbons and halogenated hydrocarbons by soil vapour extraction.  

PubMed

This paper presents the study of the remediation of sandy soils containing six of the most common contaminants (benzene, toluene, ethylbenzene, xylene, trichloroethylene and perchloroethylene) using soil vapour extraction (SVE). The influence of soil water content on the process efficiency was evaluated considering the soil type and the contaminant. For artificially contaminated soils with negligible clay contents and natural organic matter it was concluded that: (i) all the remediation processes presented efficiencies above 92%; (ii) an increase of the soil water content led to a more time-consuming remediation; (iii) longer remediation periods were observed for contaminants with lower vapour pressures and lower water solubilities due to mass transfer limitations. Based on these results an easy and relatively fast procedure was developed for the prediction of the remediation times of real soils; 83% of the remediation times were predicted with relative deviations below 14%. PMID:22561947

Albergaria, José Tomás; Alvim-Ferraz, Maria da Conceição M; Delerue-Matos, Cristina

2012-08-15

186

Background in the context of land contaminated with naturally occurring radioactive material.  

PubMed

The financial implications of choosing a particular threshold for clearance of radioactively contaminated land are substantial, particularly when one considers the volume of naturally occurring radioactive material (NORM) created each year by the production and combustion of fossil fuels and the exploitation of industrial minerals. Inevitably, a compromise needs to be reached between the level of environmental protection sought and the finite resources available for remediation. In the case of natural series radionuclides, any anthropogenic input is always superimposed on the inventory already present in the soil; this 'background' inventory is conventionally disregarded when assessing remediation targets. Unfortunately, the term is not well defined and the concept of 'background dose' is open to alternative interpretations. In this paper, we address the issue of natural background from a geochemical rather than from a solely radiological perspective, illustrating this with an example from the china clay industry. We propose a simple procedure for decision making based on activity concentrations of primordial radionuclides and their progeny. Subsequent calculations of dose need to take into account the mineralogical and chemical characteristics of the contamination, which in the case of NORM are invariably reflected in uranium series disequilibrium. PMID:23519083

Read, D; Read, G D; Thorne, M C

2013-06-01

187

Absorbed doses in tissue-equivalent spheres above radioactive sources in soil.  

PubMed

Doses due to external exposure of terrestrial biota are assessed using differential air kerma from radioactive sources in soil and energy-dependent 'absorbed dose-per-air kerma' conversion factors computed for spherical tissue-equivalent bodies. The presented approach allows computing average whole body absorbed dose for terrestrial organisms with body masses from 1 mg to 1,000 kg located at heights from 10 cm to 500 m above ground. Radioactive sources in soil emitting photons with energies from 10 keV to 10 MeV have been considered. Interpolation of the computed quantities over source energy, body mass, and height above ground results in plausible estimates of whole body average absorbed doses for non-human terrestrial biota from gamma-radiation emitted by any radionuclides in contaminated terrain. PMID:25129621

Ulanovsky, Alexander

2014-11-01

188

Remediating dinoseb-contaminated soil with zerovalent iron.  

PubMed

Dinoseb, a dinitroherbicide, was once commonly used in aerial crop dusting of agronomic crops in the western United States. Widespread use combined with improper disposal practices at rural air strips has contaminated numerous sites. Our objective was to determine if zerovalent iron (Fe(0)) could remediate dinoseb-contaminated soil. This was accomplished by conducting a series of batch experiments where we first determined if Fe(0) could remove dinoseb in aqueous solutions, then in contaminated soil slurries, and finally, in unsaturated soil microcosms (25 degrees C, theta(g)=0.30 kg H(2)O kg(-1)). Results showed quantitative dinoseb removal in the presence of Fe(0) in all three media (aqueous solutions, soil slurries, moist soils) and that removal increased by including either ferrous or aluminum sulfate with the iron treatment. Incubating contaminated soils with Fe(0) or Fe(0) plus salts (FeSO(4) or Al(2)(SO(4))(3)) resulted in 100% removal of dinoseb within 7 d. Liquid chromatography/mass spectrometry (LC/MS) analysis of degradation products showed the transformations imposed by the iron treatments were reduction of one or both nitro groups to amino groups. These amino degradation products were further transformed to quinonimine and benzoquinone and did not persist. These results support the use of zerovalent iron for on-site treatment of dinoseb-contaminated soil. PMID:19345492

Satapanajaru, T; Onanong, S; Comfort, S D; Snow, D D; Cassada, D A; Harris, C

2009-09-15

189

Remediating dinoseb-contaminated soil with zerovalent iron  

Microsoft Academic Search

Dinoseb, a dinitroherbicide, was once commonly used in aerial crop dusting of agronomic crops in the western United States. Widespread use combined with improper disposal practices at rural air strips has contaminated numerous sites. Our objective was to determine if zerovalent iron (Fe0) could remediate dinoseb-contaminated soil. This was accomplished by conducting a series of batch experiments where we first

T. Satapanajaru; S. Onanong; S. D. Comfort; D. D. Snow; D. A. Cassada; C. Harris

2009-01-01

190

Remediation of arsenic-contaminated soils and groundwaters  

DOEpatents

An in situ method is described for extraction of arsenic contaminants from a soil medium and remediation of the medium including contacting the medium with an extractant solution, directing the solution within and through the medium, and collecting the solution and contaminants. The method can also be used for arsenate and/or arsenite removal. 8 figs.

Peters, R.W.; Frank, J.R.; Feng, X.

1998-06-23

191

Remediation of arsenic-contaminated soils and groundwaters  

DOEpatents

An in situ method for extraction of arsenic contaminants from a soil medium and remediation of the medium including contacting the medium with an extractant solution, directing the solution within and through the medium, and collecting the solution and contaminants. The method can also be used for arsenate and/or arsenite removal.

Peters, Robert W. (Naperville, IL); Frank, James R. (Glen Ellyn, IL); Feng, Xiandong (West Richland, WA)

1998-01-01

192

Surfactant-enhanced remediation of organic contaminated soil and water  

Microsoft Academic Search

Surfactant based remediation technologies for organic contaminated soil and water (groundwater or surface water) is of increasing importance recently. Surfactants are used to dramatically expedite the process, which in turn, may reduce the treatment time of a site compared to use of water alone. In fact, among the various available remediation technologies for organic contaminated sites, surfactant based process is

Santanu Paria

2008-01-01

193

Bioremediation of soils and sediments contaminated by polychlorinated biphenyls  

Microsoft Academic Search

This review discusses the prospects of using the potential of microorganisms for bioremediation of PCB-contaminated natural\\u000a environments (soil, sediments, and sewage sludge) under anaerobic and aerobic conditions. A detailed analysis of the research\\u000a conditions of original works has shown that the efficiency of bioremediation of PCB-contaminated matrices strongly depends\\u000a on the character and degree of contamination. In the case of

G. K. Vasilyeva; E. R. Strijakova

2007-01-01

194

BIOCYCLE JUNE 2002 41 ETAL contaminated soils  

E-print Network

soils can be revegetated effectively using mixtures of biosolids and alkaline by-prod- ucts so hazard remediation by use of biosolids plus alkaline by-products to revegetate such soils. Limits to protect wildlife on biosolids-amended soils were developed, and may prove to be a solid technical basis

Brown, Sally

195

Test plan for the soils facility demonstration: A petroleum contaminated soil bioremediation facility  

Microsoft Academic Search

The objectives of this test plan are to show the value added by using bioremediation as an effective and environmentally sound method to remediate petroleum contaminated soils (PCS) by: demonstrating bioremediation as a permanent method for remediating soils contaminated with petroleum products; establishing the best operating conditions for maximizing bioremediation and minimizing volatilization for SRS PCS during different seasons; determining

Lombard

1994-01-01

196

Remediation of soil contaminated with dioxins by subcritical water extraction  

Microsoft Academic Search

The effectiveness of subcritical water extraction (SCWE) was examined for removing dioxins from contaminated soil. Most dioxins in the soil sample were reduced at 300 °C or more, but decreased dioxin concentrations were also observed at 150 °C. After 4 h of extraction, 99.4%, 94.5% and 60% of PCDDs were removed from samples at 350, 300 and 150 °C, respectively.

Shunji Hashimoto; Kiyohiko Watanabe; Kazutoshi Nose; Masatoshi Morita

2004-01-01

197

Leaching of heavy metals from contaminated soils using EDTA  

Microsoft Academic Search

Ethylenediaminetetraacetic acid (EDTA) extraction of Zn, Cd, Cu and Pb from four contaminated soils was studied using batch and column leaching experiments. In the batch experiment, the heavy metals extracted were virtually all as 1:1 metal-EDTA complexes. The ratios of Zn, Cd, Cu and Pb of the extracted were similar to those in the soils, suggesting that EDTA extracted the

B Sun; F. J Zhao; E Lombi; S. P McGrath

2001-01-01

198

ACID EXTRACTION TREATMENT SYSTEM FOR TREATMENT OF METAL CONTAMINATED SOILS  

EPA Science Inventory

The Acid Extraction Treatment System (AETS) reduces the concentrations and/or leachability of heavy metals in contaminated soils so the soil can be returned to the site from which it originated. he objective of the project was to determine the effectiveness and commercial viabili...

199

Assessing Plants for Phytoremediation of Arsenic-Contaminated Soils  

E-print Network

24 Assessing Plants for Phytoremediation of Arsenic-Contaminated Soils Nandita Singh and Lena Q. Ma. Phytoremediation is potentially a cost-effective and environmentally benign method of extracting pollutants from soils. Key Words: Arsenic (As); hyperaccumulation; phytoremediation; Pteris vittata. 1. Introduction

Ma, Lena

200

Soil radioactivity and incidence of cancer in Nigeria  

Microsoft Academic Search

The significance of exposure from natural radioactivity in soil and the potential risk for causing health detriment have not received adequate attention in Nigeria. Cancer has become a major cause of mortality in the recent times and now the public interest in the long-term effects of radiation on humans has assumed great prominence following the establishment of a nuclear regulatory

I. P. Farai; R. I. Obed; N. N. Jibiri

2006-01-01

201

Toxicity tests of soil contaminated by recycling of scrap plastics  

SciTech Connect

The present investigation studied the toxicity of soil contaminated by untreated discharge from a factory that recycles used plastics. The nearby agricultural areas and freshwater fish ponds were polluted with high concentrations of Cu, Ni, and Mn. Water extracts from the contaminated soil retarded root growth of Brassica chinensis (Chinese white cabbage) and Cynodon dactylon (Bermuda grass) where their seeds were obtained commercially. The contaminated populations of C. dactylon, Panicum repen (panic grass), and Imperata cylindrica (wooly grass) were able to withstand higher concentrations of Cu, Ni, and Mn, especially C. dactylon, when compared with their uncontaminated counterparts.

Wong, M.H.; Chui, V.W. (Hong Kong Baptist College, Kowloon (Hong Kong))

1990-03-01

202

Transport of PCBs with leachate water from contaminated soil  

Microsoft Academic Search

Natural soil contaminated with PCBs was used in this study. The soil was excavated from the area around the damaged capacitor of an electrical transformer station in Zadar (ETS 110\\/35kV). A lysimeter experiment was conducted for 17 months under natural climatic conditions and designed to measure the concentration of PCB in the soil and leachates. Our research field was composed

Vedranka Hodak Kobasi?; Mladen Picer; Nena Picer; Violeta ?ali?

2008-01-01

203

Selection of plants for phytoremediation of soils contaminated with radionuclides  

SciTech Connect

Remediation of soil contaminated with radionuclides typically requires that soil be removed from the site and treated with various dispersing and chelating chemicals. Numerous studies have shown that radionuclides are generally not leached from the top 0.4 meters of soil, where plant roots actively accumulate elements. Restoration of large areas of land contaminated with low levels of radionuclides may be feasible using phytoremediation. Criteria for the selection of plants for phytoremediation, molecular approaches to increase radio nuclide uptake, effects of cultural practices on uptake and assessment of environmental effects of phytoremediation will be discussed.

Entry J.A. [Auburn Univ., AL (United States); Vance, N.C. [PNW Research Station, Corvallis, OR (United States); Watrud, L.S. [National Health and Environmental Effects Research Lab., Corvallis, OR (United States)

1996-12-31

204

40 CFR 268.49 - Alternative LDR treatment standards for contaminated soil.  

...LDR treatment standards for contaminated soil. 268.49 Section 268.49 Protection...LDR treatment standards for contaminated soil. (a) Applicability. You must comply with LDRs prior to placing soil that exhibits a characteristic...

2014-07-01

205

40 CFR 268.49 - Alternative LDR treatment standards for contaminated soil.  

Code of Federal Regulations, 2010 CFR

...LDR treatment standards for contaminated soil. 268.49 Section 268.49 Protection...LDR treatment standards for contaminated soil. (a) Applicability. You must comply with LDRs prior to placing soil that exhibits a characteristic...

2010-07-01

206

Modeling of volatile organic contaminant transport in soils  

SciTech Connect

The three-dimensional model, CSUISV, was developed for approximating the removal of volatile organic compounds via in situ volatilization (ISV). The basic principle behind ISV is that by inducing soil gas flow through a contaminated region the gas-liquid contacting which occurs air strips the volatile compounds from the soil environment. CSUISV simulates the flow of gas through variably saturated soils, the transport of contaminant vapors within the gas, and accounts for the interphase mass transfer to the soil gas. The mass transfer mechanisms considered are the evaporation from free product liquid surfaces, partitioning of contaminant vapors from aqueous solution in the soil moisture, and adsorptive/desorptive interactions of contaminant vapors with the soil particle surfaces. Two contaminant transport mechanisms are considered: (1) the advective transport of the vapors within the dynamic gas; and (2) molecular diffusion of contaminant vapors through the soil pore spaces. The mass transfer rates are expressed in terms of an overall mass transfer coefficient and an overall concentration difference. The overall mass transfer coefficient characterizes the interphase mass transfer in terms of a mass transfer rate and the interfacial contact area. The mass transfer driving force is proportional to the difference between equilibrium and actual concentrations. The numerical model was verified against several analytic solutions, laboratory data, and field data. Results from the various cases show a good agreement between the model and the analytic solutions and observed data. A case study of an actual contaminated site is presented to demonstrate the applicability and use of CSUISV. The mass transport and transfer mechanisms selected are demonstrated to effectively characterize ISV operations.

Sabadell, G.P.

1989-01-01

207

Characterization of organic contamination in soil at military bases  

SciTech Connect

There is a growing concern over organic chemical residues in soil at military bases as potential point sources of contamination. In order to characterize the extent of contamination and to monitor remediation activities, soil and air sampling methods are currently under development. Soil samples obtained from USAF and US Army sites were studied by HPLC, GC and GC/MS. Soil extractions by both conventional solvent (soxhlet) and supercritical CO{sub 2} were compared for effectiveness of recovery of the contaminants. The principal organophosphate (OP) ester soil contaminant was identified as tricresyl phosphate, a component of hydraulic fluids and a known neurotoxicant. Other OP compounds under study are tributyl and triphenyl phosphate. Sampling methods for determining sources of airborne OPs were also developed. Soil samples taken from munitions ponds at a US Army base were analyzed for Trinitrotoluene (TNT) and Trinitrobenzene (TNB), the primary photolysis product of TNT. Methods for decontaminating soil containing OPs or TNT/TNB are under study, to include both chemical and biological characterization.

David, M.D.; Wujcik, C.E.; Seiber, J. [Univ. of Nevada, Reno, NV (United States). Center for Environmental Science and Engineering

1994-12-31

208

The remediation of lead contaminated soils using solvent extraction chelation techniques. Final report  

SciTech Connect

This report describes preliminary work leading to the development of an innovative technology for treating a mixed waste problem at Los Alamos National Laboratory (LANL). The specific problem being addressed by this research is the result of research activity at the Meson Physics Facility (LAMPH). The LAMPH facility conducts high energy neutron research. Lead BB`s were placed in containers and used as shielding during experiments.This lead was stored in piles on the ground when it was not in use, and it sometimes sat for extended periods of time, perhaps as long as 20 years. The lead was mobilized overtime, and contaminated the underlying soil. Because of the neutron bombardment, a portion of the lead {sup 207}Pb became radioactive {sup 210}Pb, and the lead became both a listed waste and radioactive, which classified it as a mixed waste. The contaminated soil has been removed from the site and placed in drums for storage until a suitable treatment technology can be identified. The contents of the barrels consists of a mixture of lead contaminated soil and lead BB`s.

Price, M.; Hanson, A.T.; Rudd, B.; Pickins, D.; Krause, K. [New Mexico State Univ., Las Cruces, NM (United States)

1998-08-01

209

The Allium cepa chromosome aberration test reliably measures genotoxicity of soils of inhabited areas in the Ukraine contaminated by the Chernobyl accident  

Microsoft Academic Search

The accident on the Chernobyl Nuclear Power Plant reactor IV in April 1986 led to the release of an enormous amount of radioactive material into the biosphere and to the formation of a complex pattern of nuclear contamination over a large area. As a consequence more than 5 million km2 of the soil in the Ukraine became contaminated with more

Olga Kovalchuk; Igor Kovalchuk; Andrey Arkhipov; Polina Telyuk; Barbara Hohn; Larisa Kovalchuk

1998-01-01

210

SOLVENT EXTRACTION AND SOIL WASHING TREATMENT OF CONTAMINATED SOILS FROM WOOD PRESERVING SITES: BENCH SCALE STUDIES  

EPA Science Inventory

Bench-scale solvent extraction and soil washing studies were performed on soil samples obtained from three abandoned wood preserving sites that included in the NPL. The soil samples from these sites were contaminated with high levels of polyaromatic hydrocarbons (PAHs), pentachlo...

211

The existence state in the soil of radioactive cesium from the Fukushima Dai-ichi nuclear power plant accident by imaging plate photograph  

NASA Astrophysics Data System (ADS)

In the accident of the Fukushima Daiichi nuclear power plant, the wide area in east Japan was polluted seriously with radioactive cesium. But, unlike Chernobyl, reactor core explosion did not occur in Fukushima. Therefore, it is thought that many radioactive nuclides emitted into the atmosphere were in the gas state and aerosol. However, when the imaging plate photographs of the surface soils in Fukushima was observed, many granular radionuclides existed. Then, in order to confirm a radioactive cesium of particle state, the treatment for the soils contaminated with radioactive cesium by using chemical operation was tried. Three type soils, that is, paddy soil, river sediment, and sea sand, were made applicable to research. The contaminated soil samples were collected in Fukushima and Ibaraki prefecture. Radioactivity concentrations of 137Cs and 134Cs were measured by using gamma-ray spectrometry with a high pure germanium (HPGe) detector. After the radioactively measurement, soils had been burned in oven for five hours in 500 degree Celsius. Concentrated hydrochloric acid was added to soil samples, and they were heated for three hours. These samples were divided into residue and elution by centrifugal separation, and then radioactivity of cesium contained in residue was measured. After chemical operations, 70% and 85% of radioactive cesium from river sediment and sea sand were extracted approximately into elution, respectively. In contrast, in the soil of the paddy field, only 30% of radioactive cesium was approximately eluted. When radiation image photograph of the residues of all three types of soils were taken and observed, the granular radioactive nuclides remained clearly in paddy soil and river sediment. In contrast, all the granular radioactive nuclides in sea sand disappeared after treatment. The results of above things that desorption of radioactive cesium depend on the kind of soil. Furthermore, it was suggested that there was radioactive cesium of particle state in paddy soil and river sediment. It is a possibility that the substances on which radioactive cesium are concentrated depends on the kind of soil. The necessity of clarifying adsorption objects and particle state in the actual condition was suggested to elucidate Fukushima accident in more detail.

Satou, Yukihiko; Sueki, Keisuke

2013-04-01

212

Auxiliary analyses in support of performance assessment of a hypothetical low-level waste facility: Two-phase flow and contaminant transport in unsaturated soils with application to low-level radioactive waste disposal. Volume 2  

Microsoft Academic Search

A numerical model of multiphase air-water flow and contaminant transport in the unsaturated zone is presented. The multiphase flow equations are solved using the two-pressure, mixed form of the equations with a modified Picard linearization of the equations and a finite element spatial approximation. A volatile contaminant is assumed to be transported in either phase, or in both phases simultaneously.

P. Binning; M. A. Celia; J. C. Johnson

1995-01-01

213

Soil contamination with emissions of non-ferrous metallurgical plants  

NASA Astrophysics Data System (ADS)

The upper soil horizons are strongly contaminated in the area influenced by the Mid-Urals copper smelter. In the technogenic desert and impact zones, the contents of a number of elements (Cu, Zn, As, Pb, P, and S) by many times exceed their clarke values and the maximum permissible concentrations (or provisional permissible concentrations). The degree of technogeneity (Tg) for these elements is very high in these zones. In the far buffer zone, Tg is about zero for many elements and increases up to Tg = 27-42% for four heavy elements (Cu, Zn, Pb, and As) and up to 81-98% for P and S. The buffer capacity of the humus horizon depends on the soil's location within the technogeochemical anomaly and also on the particular pollutant. In the impact zone, it is equal to 70-77% for lead and arsenic, although other technogenic elements (Zn, Cr, S, and P) are poorly retained and readily migrate into the deeper horizons (the buffer capacity is equal to 14-25%). Nearly all the heavy metals enter the soil in the form of sulfides. The soils in the area affected by the Noril'sk mining and smelting metallurgical enterprise are subdivided into two groups according to the degree of their contamination, i.e., the soils within Noril'sk proper and the soils in its suburbs to a distance of 4-15 km. The strongest soil contamination is recorded in the city: the clarke values are exceeded by 287, 78, 16, 4.1, and 3.5 times for Cu, Ni, Cr, Fe, and S, respectively. The major pollutants enter the soil from the ferruginous slag. The soil's contamination degree is lower in the suburbs, where heavy metal sulfides reach the soils with the aerial emission from the enterprise.

Vodyanitskii, Yu. N.; Plekhanova, I. O.; Prokopovich, E. V.; Savichev, A. T.

2011-02-01

214

Environmental projects. Volume 14: Removal of contaminated soil and debris  

NASA Technical Reports Server (NTRS)

Numerous diverse activities at the Goldstone Deep Space Communications Complex (GDSCC) are carried out in support of six parabolic dish antennas. Some of these activities can result in possible spills or leakages of hazardous materials and wastes stored both above ground in steel drums and below ground in underground storage tanks (UST's). These possible leaks or spills, along with the past practice of burial of solid debris and waste in trenches and pits, could cause local subsurface contamination of the soil. In 1987, the Jet Propulsion Laboratory (JPL), retained Engineering-Science, Inc. (E-S), Pasadena, California, to identify the specific local areas within the GDSCC with subsurface soil contamination. The E-S study determined that some of the soils at the Apollo Site and the Mars Site were contaminated with hydrocarbons, while soil at a nonhazardous waste dumpsite at the Mojave Base site was contaminated with copper. This volume is a JPL-expanded version of the PE209 E-S report, and it also reports that all subsurface contaminated soils at the GDSCC were excavated, removed, and disposed of in an environmentally acceptable way, and the excavations were backfilled and covered in accordance with accepted Federal, State, and local environmental rules and regulations.

Kushner, Len

1992-01-01

215

Use of passive sampling devices to determine soil contaminant concentrations  

SciTech Connect

The effective remediation of contaminated sites requires accurate identification of chemical distributions. A rapid sampling method using passive sampling devices (PSDs) can provide a thorough site assessment. We have been pursuing their application in terrestrial systems and have found that they increase the ease and speed of analysis, decrease solvent usage and overall cost, and minimize the transport of contaminated soils. Time and cost savings allow a higher sampling frequency than is generally the case using traditional methods. PSDs have been used in the field in soils of varying physical properties and have been successful in estimating soil concentrations ranging from 1 {mu}g/kg (parts per billion) to greater than 200 mg/kg (parts per million). They were also helpful in identifying hot spots within the sites. Passive sampling devices show extreme promise as an analytical tool to rapidly characterize contaminant distributions in soil. There are substantial time and cost savings in laboratory personnel and supplies. By selectively excluding common interferences that require sample cleanup, PSDs can be retrieved from the field and processed rapidly (one technician can process approximately 90 PSDs in an 8-h work day). The results of our studies indicate that PSDs can be used to accurately estimate soil contaminant concentrations and provide lower detection limits. Further, time and cost savings will allow a more thorough and detailed characterization of contaminant distributions. 13 refs., 4 figs., 2 tabs.

Johnson, K.A. [Clemson Univ., Pendleton, SC (United States); [Washington State Univ., Richland, WA (United States); Hooper, M.J. [Clemson Univ., Pendleton, SC (United States); Weisskopf, C.P. [Washington State Univ., Richland, WA (United States)

1996-12-31

216

Environmental projects. Volume 14: Removal of contaminated soil and debris  

SciTech Connect

Numerous diverse activities at the Goldstone Deep Space Communications Complex (GDSCC) are carried out in support of six parabolic dish antennas. Some of these activities can result in possible spills or leakages of hazardous materials and wastes stored both above ground in steel drums and below ground in underground storage tanks (UST's). These possible leaks or spills, along with the past practice of burial of solid debris and waste in trenches and pits, could cause local subsurface contamination of the soil. In 1987, the Jet Propulsion Laboratory (JPL), retained Engineering-Science, Inc. (E-S), Pasadena, California, to identify the specific local areas within the GDSCC with subsurface soil contamination. The E-S study determined that some of the soils at the Apollo Site and the Mars Site were contaminated with hydrocarbons, while soil at a nonhazardous waste dumpsite at the Mojave Base site was contaminated with copper. This volume is a JPL-expanded version of the PE209 E-S report, and it also reports that all subsurface contaminated soils at the GDSCC were excavated, removed, and disposed of in an environmentally acceptable way, and the excavations were backfilled and covered in accordance with accepted Federal, State, and local environmental rules and regulations.

Kushner, L.

1992-03-01

217

Radioactivity in Northern Ireland soils - December 1986. Final report.  

National Technical Information Service (NTIS)

The main objective of the survey was to establish the radionuclide content of permanent pasture soils. The extent of contamination from the Chernobyl accident was also studied with the use of Cs-134 as an indicator of Chernobyl fallout. A preliminary radi...

D. W. K. Jenkins

1989-01-01

218

Bioremediation of oil-contaminated soils by composting  

NASA Astrophysics Data System (ADS)

Composting oil-contaminated soils under field conditions with the simultaneous optimization of their physicochemical and agrochemical parameters revealed the high efficiency of the soil purification, including that from benz[a]pyrene. The application of fertilizers and lime favored the intense development of indigenous microcenoses and the effective destruction of the oil. During the 95-day experimental period, the average daily rate of the oil decomposition was 157 mg/kg of soil. After the completion of the process, the soil became ecologically pure.

Golodyaev, G. P.; Kostenkov, N. M.; Oznobikhin, V. I.

2009-08-01

219

Bioremediation of RDX-contaminated soil: A preliminary field trial  

SciTech Connect

The biotreatability of a clay soil contaminated with of 1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) at nominal 2000 mg/kg and 500 mg/kg, respectively, was examined in small scale biopiles. These piles were prepared from concentrated soils having RDX and HMX contamination levels of 100,000 mg/kg and 25,000 mg/kg, respectively. The overall soil composition of the piles was a mixture of clay, sand and black earth. The 4 m{sup 3} biopiles were set up in wooden forms having impermeable plastic liners, and were equipped with a spray irrigation system allowing a closed-loop recirculation of the aqueous leachate from the pile. Lime and alfalfa were used as soil amendments. The physical and chemical parameters of the piles were monitored over a period of 4 months. The analysis of soil samples for the determination of RDX and HMX concentrations was carried out by acetonitrile extraction and high performance liquid chromatography. The results showed a rapid decrease in contaminants concentrations with no significant lag time. The biopile with amended soil achieved a complete degradation of explosives contaminants. Finally, scale-up aspects of this bioremediation process will be discussed.

Dubois, C.; Ampleman, G.; Thiboutot, S. [Defence Research Establishment, Val-Belair, Quebec (Canada); Greer, C.W.; Hawari, J.; Sunahara, G. [National Research Council of Canada, Montreal, Quebec (Canada)

1997-12-31

220

Release of polyaromatic hydrocarbons from coal tar contaminated soils  

SciTech Connect

A variety of process wastes generated from manufactured gas production (MGP) have contaminated soils and groundwater at production and disposal sites. Coal tar, consisting of a complex mixture of hydrocarbons present as a nonaqueous phase liquid, makes up a large portion of MGP wastes. Of the compounds in coal tar, polyaromatic hydrocarbons (PAHs) are the major constituents of environmental concern due to their potential mutagenic and carcinogenic hazards. Characterization of the release of PAHs from the waste-soil matrix is essential to quantifying long-term environmental impacts in soils and groundwater. Currently, conservative estimates for the release of PAHs to the groundwater are made assuming equilibrium conditions and using relationships derived from artificially contaminated soils. Preliminary work suggests that aged coal tar contaminated soils have much lower rates of desorption and a greater affinity for retaining organic contaminants. To obtain better estimates of desorption rates, the release of PAHs from a coal tar soil was investigated using a flow-interruption, miscible displacement technique. Methanol/water solutions were employed to enhance PAH concentrations above limits of detection. For each methanol/water solution employed, a series of flow interrupts of varying times was invoked. Release rates from each methanol/water solution were estimated from the increase in concentration with duration of flow interruption. Aqueous-phase release rates were then estimated by extrapolation using a log-linear cosolvency model.

Priddy, N.D.; Lee, L.S. [Purdue Univ., West Lafayette, IN (United States). Dept. of Agronomy

1996-11-01

221

Patterns and inventories of radioactive contamination of island sites of the Yenisey River, Russia  

Microsoft Academic Search

The distribution of radioactive contamination at three island sites downstream from the Krasnoyarsk Mining and Chemical Combine (KMCC) was studied with the objectives of mapping contamination levels, interpreting radionuclide distributions through consideration of alluvial processes and determining radionuclide inventories. Contamination was measured using in situ gamma spectrometry and landforms characterised using topographic surveying methods. Maximum 137Cs contamination densities (700kBqm?2) were

V. G. Linnik; J. E. Brown; M. Dowdall; V. N. Potapov; A. V. Nosov; V. V. Surkov; A. V. Sokolov; S. M. Wright; S. Borghuis

2006-01-01

222

Interaction of soil, water and TNT during degradation of TNT on contaminated soil using subcritical water.  

PubMed

Subcritical water was used at laboratory scale to reveal information with respect to the degradation mechanism of TNT on contaminated soil. Highly contaminated soil (12% TNT) was heated with water at four different temperatures, 150, 175, 200 and 225 degrees C and samples were obtained at appropriate time intervals. At the same time, similar experiments were performed with TNT spiked on to clean soil, sand and pure water in order to compare and eliminate various factors that may be present in the more complex contaminated soil system. Subcritical water was successful at remediating TNT-contaminated soil. TNT destruction percentages ranged between 98 and 100%. The aim of this work was to study the soil-water-contaminant interaction and determine the main physical parameters that affect TNT degradation. It was shown that the rate-limiting step of the process is the extraction/diffusion of TNT molecules from the soil core to the soil surface, where they degrade. Additionally, it was determined that the soil matrix also catalyses degradation to a lesser extent. Autocatalytic effects were not clearly observed. PMID:18384944

Kalderis, Dimitrios; Hawthorne, Steven B; Clifford, Anthony A; Gidarakos, Evangelos

2008-11-30

223

Electrokinetic remediation of soils contaminated with electroplating wastes  

SciTech Connect

Electrokinetic remediation of soils simulated with electroplating waste contamination was investigated in two soils, kaolin and glacial till. Soil samples were contaminated with nickel, cadmium and hexavalent chromium and subjected to an external electric field for four days. Results of these experiments revealed that the soil composition plays an important role in electrokinetic remediation. Due to induced electric potential, a distinct pH gradient was developed in kaolin; however, in glacial till alkaline conditions existed throughout the soil because of its high carbonate buffering capacity. The movement of cationic metallic contaminants, Ni(II) and Cd(II), from the anode to the cathode was significant in kaolin as compared to glacial till. Because of high pH conditions near the cathode, Ni(II) and Cd(II) were precipitated in kaolin. In glacial till, however, because of alkaline conditions throughout the soil, most of Ni(II) and Cd(II) precipitated without migration. Overall, this study demonstrates that anion exchange, cation exchange and precipitation were the significant fixation mechanisms of nickel, cadmium and chromium in soils.

Reddy, K.R.; Parupudi, U.S. [Univ. of Illinois, Chicago, IL (United States). Dept. of Civil and Materials Engineering; Devulapalli, S. [Patterson Associates Inc., Chicago, IL (United States)

1996-10-01

224

Mercury uptake by Silene vulgaris grown on contaminated spiked soils.  

PubMed

Mercury is a highly toxic pollutant with expensive clean up, because of its accumulative and persistent character in the biota. The objective of this work was to evaluate the effectiveness of Silene vulgaris, facultative metallophyte which have populations on both non-contaminated and metalliferous soils, to uptake Hg from artificially polluted soils. A pot experiment was carried out in a rain shelter for a full growth period. Two soils (C pH = 8.55 O.M. 0.63% and A pH = 7.07 O.M. 0.16%) were used, previously contaminated with Hg as HgCl(2) (0.6 and 5.5 mg Hg kg(-1) soil). Plants grew healthy and showed good appearance throughout the study without significantly decreasing biomass production. Mercury uptake by plants increased with the mercury concentration found in both soils. Differences were statistically significant between high dosage and untreated soil. The fact that S. vulgaris retains more mercury in root than in shoot and also, the well known effectiveness of these plants in the recovering of contaminated soils makes S. vulgaris a good candidate to phytostabilization technologies. PMID:20708330

Pérez-Sanz, Araceli; Millán, Rocío; Sierra, M José; Alarcón, Remedios; García, Pilar; Gil-Díaz, Mar; Vazquez, Saúl; Lobo, M Carmen

2012-03-01

225

Magnetic mineralogy of heavy metals-contaminated soils  

NASA Astrophysics Data System (ADS)

Soils around mine and in urban areas are often contaminated by heavy metals derived from industrial and human activities [1, 2]. These contaminated soils are often characterized by a magnetic enhancement on topsoils. Many studies demonstrated that there are significant correlations between heavy metals and various magnetic parameters in contaminated soils, indicating a strong affinity of heavy metals to magnetic minerals. The magnetic particles in contaminated soils were separated by a magnetic separation technique. The rock magnetism, XRD, field emission scanning electron microscopy equiped with an energy-dispersive X-ray analyzer (FESEM/EDX) were used to characterize their magnetic mineralogy. Results of XRD analysis indicated that the magnetic particles separated from heavy metal-contaminated soils are composed of quartz, magnetite, and hematite. Based on the X-ray diffraction peak intensity, the Fe3O4 was identified as the predominant magnetic mineral phase. The high-temperature magnetization (Ms-T) curves of magnetic particles extracted from contaminated soils show a sharp Ms decrease at about 580C (the Curie temperature of magnetite), suggesting that magnetite is the dominant magnetic carrier. The hysteresis loops of contaminated soils are closed at about 100-200 mT which is consistent with the presence of a dominant ferrimagnetic mineral phase. The FESEM analysis showed a great variety of shapes of magnetic particles in contaminated soils. The most common morphology are observed in the form of spherules, with the sizes ranging from 20 to 100 um. The chemical composition of magnetic particles consist mainly of Fe, Si, Al, and Ca with minor heavy metal elements (Cu, Zn, Hg, and Cr). The semi-quantitative Fe content identified by FESEM/EDX ranged from 40 to 90%. Combined studies of rock magnetism, XRD, and FESEM/EDX indicated that magnetic mineral phases responsible for the magnetic enhancement of contaminated soils are anthropogenic origin which are coarse-grained multi-domain (MD) ferrimagnetic minerals. These spherical magnetic particles in contaminated soils are most likely related to airborne particles from coal combusition and industrial activities. Coal burning, metallurgical and industrial dusts contain a significant fraction of ferrimagnetic minerals. The magnetic particles in fly ash from coal-burning power plant have a typical spherical morphology, ranging from 10 to 100 ?m. Vehicle emissions have been suggested to be another source of magnetic particles. These anthropogenic ferrimagnetic mineral phases are directly responsible for the magnetic enhancement in the contaminated soils. Therefore, the strong magnetic signature in contaminated soils can be used as an effective tool for identifying pollution sources and quantifying pollution level of heavy metals. Acknowledgements: This research was supported by National Nature Science Foundation of China (No. 41171182 and 40971131) and the Ph.D. Programs Foundation of Ministry of Education of China (20090101110088). [1] Lu, S.G. & Bai, S.Q. (2006) J. Appl. Geophys., 60, 1-12. [2] Lu, S.G., Bai, S.Q. & Xue, Q.F. (2007) Geophys. J. Inter., 171, 568-580.

Shenggao, L.

2012-04-01

226

Coupling Sorption to Soil Weathering during Reactive Transport: Impacts of Mineral Transformation and Sorbate Aging on Contaminant Speciation and Mobility  

SciTech Connect

The Hanford subsurface has become contaminated with highly alkaline, radioactive waste generated as a result of weapons production. The radioactive brine was stored in underground storage tanks, a number of which developed leaks and contaminated the surrounding subsurface. The high pH and ionic strength of these wastes has been predicted to accelerate the degree of soil weathering to produce new mineral phases--cancrinite and sodalite among the most abundant. Previous work has demonstrated that Cs and Sr, which along with I represent the most radioactive components in the waste, are sequestered by these neo-formed solids. The present work is aimed at assessing the stability of these neo-formed solids, with special emphasis on the degree of Cs, Sr and I release under ambient (neutral pH, low ionic strength) conditions expected to return to the Hanford area after the caustic radioactive brine waste is removed.

Carl I. Steefel; Aaron Thompson; Jon Chorover

2006-06-01

227

Landfarming Process Effects on Biochemical Properties of Petroleum-Contaminated Soils  

Microsoft Academic Search

The presence of petroleum contaminants in soil may be toxic to humans, plants, and soil microorganisms. Therefore, remediation of these compounds from the environment is vital. In this study, bioremediation of two petroleum-contaminated soils (S1 and S2) using a landfarming technique was evaluated. Investigation of the effect of this technique on biological and chemical properties of contaminated soil was also

A. Besalatpour; M. A. Hajabbasi; A. H. Khoshgoftarmanesh; V. Dorostkar

2011-01-01

228

Contamination of Austrian soil with caesium-137.  

PubMed

Austria ranks among the countries that have been most strongly affected by the Chernobyl fallout. The mean contamination with 137Cs is 21.0 kBq/m2, of which 18.7 kBq/m2 is due to the Chernobyl accident, whereas global fallout contributes 2.3 kBq/m2. Maximum values of total 137Cs contamination are nearly 200 kBq/m2. Total deposition of Chernobyl 137Cs on Austrian territory is 1.6 PBq or a fraction of around 2% of the 137Cs released from the reactor. 2115 measurements were used to draw the Austrian "caesium map". The geographical pattern of fallout distribution shows regional differences of contamination as high as 1:100. PMID:11398378

Bossew, P; Ditto, M; Falkner, T; Henrich, E; Kienzl, K; Rappelsberger, U

2001-01-01

229

Sorption of radioactive contaminants by sediment from the Kara Sea  

SciTech Connect

The purpose of this study is to quantify some of the parameters needed to perform near-field modeling of sites in the Kara Sea that were impacted by the disposal of radioactive waste. The parameters of interest are: the distribution coefficients (K{sub d}) for several important radionuclides, the mineralogy of the sediment, and the relationship of K{sub d} to liquid to solid ratio. Sediment from the Kara Sea (location: 73{degrees} 00` N, 58{degrees} 00` E) was sampled from a depth of 287 meters on August 23/24, 1992, during a joint Russian/Norwegian scientific cruise. Analysis of the material included mineralogy, grain size and total organic carbon. Uptake kinetics were determined for {sup 85}Sr, {sup 99}Tc, {sup 125}I, {sup 137}Cs, {sup 210}Pb, {sup 232}U, and {sup 241}Am and distribution coefficients (K{sub d}) were determined for these radionuclides using batch type experiments. Sorption isotherms were developed for {sup 85}Sr, {sup 99}Tc, and {sup 137}Cs to examine the effect that varying the concentration of a tracer has on the quantity of that tracer taken up by the solid. The effect of liquid to solid ratio on the uptake of contaminants was determined for {sup 99}Tc and {sup 137}Cs. In another set of experiments, the sediment was separated into four size fractions and uptake was determined for each fraction for {sup 85}Sr, {sup 99}Tc, and {sup 137}Cs. In addition, the sediment was analyzed to determine if it contains observable concentrations of anthropogenic radionuclides.

Fuhrmann, M.; Zhou, H. [Brookhaven National Lab., Upton, NY (United States); Neiheisel, J.; Dyer, R.

1995-02-01

230

Phytoremediation of Loess Soil Contaminated by Organic Compounds  

Microsoft Academic Search

Loess soils extensively cover Central Asia and North China topography where oil fields are widely exploited; thus, organic\\u000a contamination has become a critical environmental issue in these regions. As China faces severe land and eco-environmental\\u000a deterioration, phytoremediation has been considered as a priority remedial alternative for reclamation of contaminated cultivated\\u000a land. This article provides a framework to understand phytore-mediation applications

K. Zhu; H. Chen; Z. Nan

231

Depleted uranium mobility and fractionation in contaminated soil (Southern Serbia)  

Microsoft Academic Search

Goal, Scope and Background  During the Balkan conflict in 1999, soil in contaminated areas was enriched in depleted uranium (DU) isotopic signature, relative\\u000a to the in-situ natural uranium present. After the military activities, most of kinetic DU penetrators or their fragments remained\\u000a buried in the ground in certain geomorphological and geochemical environments exposed to local weathering conditions. The\\u000a contamination distribution, mobility

Mirjana B. Radenkovi?; Svjetlana A. Cupa?; Jasminka D. Joksi?; Dragana J. Todorovi?

2008-01-01

232

Phytoremediation of contaminated soils: Progress and promise  

SciTech Connect

{open_quotes}Phytoremediation{close_quotes} refers to the use of green plants, including plant-associated microflora, to remediated contaminated sites. The talk addresses the remediation of solids only, although green-plant based systems are well established in waste-water treatment and air pollution control. Phytoremediation has potential significant economic, regulatory and aesthetic advantages over many engineering-based solutions. The technology can be targeted to both inorganic and organic contaminants. The focus of this talk will be on lead (Pb). A brief overview of activities in organic remediation will be included at the end of the talk.

Cunningham, S.D.; Berti, D.R.; Dupont, E.I. [Glasgow Business Community, Newark, DE (United States)

1993-12-31

233

Extraction of pesticides from contaminated soil using supercritical carbon dioxide  

SciTech Connect

The demand for processes to clean up contaminated soils without generating additional contaminants, such as hazardous solvents, is increasing. One approach to minimizing this problem is to use supercritical fluids like light hydrocarbons and CO[sub 2] to extract contaminants from soils. Gases exhibit unique properties under supercritical conditions. They retain the ability to diffuse through the interstitial spaces of solid materials, plus they have the solvating power of liquids. Some examples of extractions using SCFs are caffeine from coffee, cholesterol from eggs, drugs from plants, and nicotine from tobacco. Supercritical CO[sub 2] is an attractive, alternative extraction medium for removal of pesticides from soils. Carbon dioxide is readily available, relatively inexpensive, and if recycled, nonpolluting. Contaminants may be easily recovered by evaporating the CO[sub 2] into an expansion vessel. Supercritical fluid extraction technology is discussed and results are given for the extraction of atrazine, bentazon, alachlor, and permethrin from contaminated soil prepared in the laboratory. Initial studies show >95% removal for these pesticides.

Hunter, G.B.

1991-01-01

234

Extraction of pesticides from contaminated soil using supercritical carbon dioxide  

SciTech Connect

The demand for processes to clean up contaminated soils without generating additional contaminants, such as hazardous solvents, is increasing. One approach to minimizing this problem is to use supercritical fluids like light hydrocarbons and CO{sub 2} to extract contaminants from soils. Gases exhibit unique properties under supercritical conditions. They retain the ability to diffuse through the interstitial spaces of solid materials, plus they have the solvating power of liquids. Some examples of extractions using SCFs are caffeine from coffee, cholesterol from eggs, drugs from plants, and nicotine from tobacco. Supercritical CO{sub 2} is an attractive, alternative extraction medium for removal of pesticides from soils. Carbon dioxide is readily available, relatively inexpensive, and if recycled, nonpolluting. Contaminants may be easily recovered by evaporating the CO{sub 2} into an expansion vessel. Supercritical fluid extraction technology is discussed and results are given for the extraction of atrazine, bentazon, alachlor, and permethrin from contaminated soil prepared in the laboratory. Initial studies show >95% removal for these pesticides.

Hunter, G.B.

1991-12-31

235

Phytoremediation of subarctic soil contaminated with diesel fuel.  

PubMed

The effects of several plant species, native to northern latitudes, and different soil amendments, on diesel fuel removal from soil were studied. Plant treatments included Scots Pine (Pinus sylvestris), Poplar (Populus deltoides x Wettsteinii), a grass mixture (Red fescue, Fesuca rubra; Smooth meadowgrass, Poa pratensis and Perennial ryegrass, Lolium perenne) and a legume mixture (White clover, Trifolium repens and Pea, Pisum sativum). Soil amendments included NPK fertiliser, a compost extract and a microbial enrichment culture. Diesel fuel disappeared more rapidly in the legume treatment than in other plant treatments. The presence of poplar and pine enhanced removal of diesel fuel, but removal under grass was similar to that with no vegetation. Soil amendments did not enhance diesel fuel removal significantly. Grass roots accumulated diesel-range compounds. This study showed that utilisation of selected plants accelerates removal of diesel fuel in soil and may serve as a viable, low-cost remedial technology for diesel-contaminated soils in subarctic regions. PMID:12118697

Palmroth, Marja R T; Pichtel, John; Puhakka, Jaakko A

2002-09-01

236

Leaching Behaviors of Five Arsenic-Contaminated Soils  

NASA Astrophysics Data System (ADS)

The vadose zone is susceptible to anthropogenic arsenic contamination and may serve as a long-term source of arsenic to ground water. Understanding the processes governing the distribution of arsenic between the aqueous phase and the solid phase is crucial to minimizing the environmental impact of vadose zone contamination. Arsenic can be retained by several soil components through adsorption. The magnitude and controlling factors of arsenic adsorption by these individual components have been investigated by a number of researchers. The desorption behavior of arsenic in bulk soil from actual contaminated sites, however, is rarely reported. Soil samples were collected from five sites contaminated with herbicide containing arsenic trioxide. The environmentally available element concentrations of each soil were determined by microwave-assisted acid digestion (MWD) and ICP-AES analysis. A ferrous sulfate solution was applied to the contaminated soil to precipitate ferric hydroxide as an arsenic fixation method. Sequential leaching experiments were performed upon the treated and untreated soil samples to evaluate the effectiveness of the treatment method. Supernatant leachate solutions were analyzed for total arsenic by ICP-AES. MWD results showed that the original soils contain 47 to 316 ppm arsenic, on a dry weight basis. The arsenic concentrations in the initial leachate ranged from 0.42 to 1.37 ppm for the untreated soils. Due to the high Kd values of the rainwater leachable portion of the soil arsenic, 500 to 4000 pore volumes of SPLP solution were required to bring the leachate arsenic concentration below the MCL for arsenic (50 ppb). In contrast, the ferrous sulfate treatment successfully transferred the loosely adsorbed portion of the soil arsenic to strongly bonded adsorption sites on ferric hydroxide. After treatment, the two soil samples with low calcium content lost their pH buffer capacity and their leachate maintained a pH value of 4.5. No arsenic was detected in the leachate of these two treated samples during three months of sequential leaching. For the other three soils with higher buffer capacity, the treated samples also showed significant decrease in both initial (56-86% decrease) and overall (43-62% decrease) release of arsenic.

Qi, Y.; Donahoe, R. J.; Graham, E. Y.

2005-12-01

237

Phytoremediation potential of Brassica juncea in Cu-pyrene co-contaminated soil: comparing freshly spiked soil with aged soil.  

PubMed

A comparison was made between the dissipation of pyrene as well as the uptake of copper (Cu) in soil freshly spiked with Cu, pyrene or Cu + pyrene and in aged soil. The potential of B juncea for phytoremediation was also investigated. The biomass of Brassica juncea significantly decreased (>50% reduction) in freshly spiked soil when compared to aged soil in all treatments. However, the accumulation of Cu in shoot was significantly reduced (60-88%) in aged soil after 60 days of planting. The total removal of Cu from co-contaminated soil was always higher (>2-3 fold) in aged soil than in freshly spiked soil when lower Cu concentration (50 mg kg(-1)) was co-contaminated with 250 or 500 mg kg(-1) of pyrene while in other co-contaminated treatments, the total removal of Cu from aged soil were significantly lower. The level of pyrene in both planted and un-planted freshly spiked soil decreased significantly (>67%) over the 60 days of plant trial. In aged soils, there were no significant differences in residual pyrene concentration between planted and unplanted soil. This suggests that the presence of B. juncea in aged soil did not enhance the dissipation of pyrene and that the prediction of pyrene dissipation in laboratory prepared soil may not have reflected the true situation in the fields. PMID:23792886

Chigbo, Chibuike; Batty, Lesley

2013-11-15

238

Magnetic susceptibility properties of pesticide contaminated volcanic soil  

NASA Astrophysics Data System (ADS)

Pesticides, unfortunately, are still widely used in many countries as way to eradicate agricultural pests. As they are being used continuously over a long period of time, they accumulate as residues in soils posing serious threats to the environment. In this study, we study the changes in magnetite-rich volcanic soils that were deliberately contaminated by pesticide. Such changes, in any, would be useful in the detection of pesticide residue in contaminated soils. Two different types of magnetically strong volcanic soil from the area near Lembang, West Java, Indonesia were used in this study where they were contaminated with varying concentrations of pesticide. The samples were then measured for magnetic susceptibility at two different frequencies. The measurements were then repeated after a period of three months. We found a reduction of magnetic susceptibility as well as a reduction in SP (superparamagnetic) grains proportion in contaminated soil. These might be caused by pesticide-induced magnetic dissolution as supported by SEM analyses. However the impact of pesticide concentration as well as exposure time on magnetic dissolution is still inconclusive.

Agustine, Eleonora; Fitriani, Dini; Safiuddin, La Ode; Tamuntuan, Gerald; Bijaksana, Satria

2013-09-01

239

Extraction of copper in a contaminated soil onto chabazite  

NASA Astrophysics Data System (ADS)

Copper in a contaminated soil nearby a printed-circuit board waste recycling plant has been extracted onto a microporous molecular sieve (chabazite). The chabazite supported CuO can be used as a chemical looping combustion (CLC) oxygen carrier for CO2 capture. Speciation of copper in the contaminated soil and on the chabazite during CLC has been studied by X-ray absorption near edge structure (XANES) and X-ray absorption fine structure (EXAFS) spectroscopy. By XANES, it is found that about 90% of copper (mainly Cu2+) in the contaminated soil can be extracted and adsorbed on the chabazite, in which CuO can be formed on the chabazite after calcination at 773 K for two hours. The EXAFS data show that copper in the soil and chabazite possesses Cu-O bond distances of 1.96 and 1.95 Å, respectively and coordination numbers (CNs) of 1-3. After CLC, CuO on chabazite has been reduced to Cu with a C-C bond distance of 2.4 Å and a CN of 8. This work also exemplifies the utilization of EXAFS and XANES to reveal the migration path of copper between a contaminated soil and a molecular sieve and interconversion of Cu-CuO in the CLC process.

Liao, P.-H.; Wang, H. Paul; Hsiao, M.-C.; Eyring, Edward M.; Huang, C.-H.; Jou, C.-J. G.

2009-04-01

240

Soil immobilization: new concept for biotreatment of soil contaminants.  

PubMed

A new concept for the development of microbial consortia for the degradation of persistent soil pollutants and for pollutant treatment is proposed. The concept defined as "soil immobilization" is based on the entrapment of soil particles, showing microbial activity in degrading the target pollutant, into a solid membrane with a large pore size distribution. The particular hydrodynamic and mass transfer properties of this system result in a very efficient process. A new type of bioreactor is proposed for carrying out the immobilized soil process. The performance of the system was tested by developing a microbial system for the mineralization of pentachlorophenol (PCP). The results show that the volumetric efficiency of the process for PCP mineralization in the immobilized soil bioreactor is 1-3 orders of magnitude higher than reported literature values. Chlorine and carbon atoms of PCP are both nearly completely (99%) mineralized. PMID:10099224

Karamanev, D G; Chavarie, C; Samson, R

1998-02-20

241

Chemical oxidation treatment of petroleum contaminated soil using Fenton's reagent  

Microsoft Academic Search

Fenton's reagent, a strong oxidant, was evaluated for suitability to treat soils contaminated with 2?methylnaphthalene (an aromatic compound), n?hexdecane (an aliphatic compound) and diesel fuel (a complicated hydrocarbon mixture). Laboratory?scale results show that Fenton's reagent reacts rapidly with these materials in soil, and will completely mineralize them if enough hydrogen peroxide is added. The effectiveness of the reaction at neutral

Chien T. Chen; Anthony N. Tafuri; Maqsud Rahman; Mary B. Foerst

1998-01-01

242

Chemical and radiochemical characterization of depleted uranium in contaminated soils  

Microsoft Academic Search

The main results of chemical and radiochemical characterization and fractionation of depleted uranium in soils contaminated\\u000a during the Balkan conflict in 1999 are presented in the paper. Alpha-spectrometric analysis of used depleted uranium material\\u000a has shown the presence of man-made radioisotopes 236U, 237Np, and 239, 240Pu traces. The fractionation in different soil types was examined by the application of a

M. B. Radenkovi?; A. B. Kandi?; I. S. Vukana?; J. D. Joksi?; D. S. Djordjevi?

2007-01-01

243

Potential for phytoextraction of PCBs from contaminated soils using weeds  

Microsoft Academic Search

A comprehensive investigation of the potential of twenty-seven different species of weeds to phytoextract polychlorinated biphenyls (PCBs) from contaminated soil was conducted at two field sites (Etobicoke and Lindsay) in southern Ontario, Canada. Soil concentrations were 31?g\\/g and 4.7?g\\/g at each site respectively. All species accumulated PCBs in their root and shoot tissues. Mean shoot concentrations at the two sites

Sarah A. Ficko; Allison Rutter; Barbara A. Zeeb

2010-01-01

244

Geochemistry of lead contaminated wetland soils amended with phosphorus  

NASA Astrophysics Data System (ADS)

To remediate Pb contaminated soils it is proposed that phosphorus can be amended to the soils to transform the Pb into poorly soluble Pb-phosphate mineral phases. However, remediation strategies must account for variable Pb speciation and site-specific factors. In this study soil mineralogy and Pb speciation in soils from P-amended field trials at sites within the Coeur d’Alene River Basin in Idaho, USA were investigated. The soils are contaminated from mining activities and are enriched with Fe and Mn. Selective extraction of the soils indicated that the Fe oxides are poorly crystalline. XRD of the soil clay size fractions identified quartz, muscovite, kaolinite, siderite, lepidocrocite, and chlorite minerals. Amendment with P fertilizer dissolved the siderite. No Pb-phosphate minerals were detected by XRD. Electron microprobe analysis showed direct correlations between Pb, Fe, and Mn in the unamended soils, and negative correlations between Pb and Si. Lead and Mn were strongly correlated. In the amended soils Fe and P were strongly correlated. Results indicate that the Pb is associated with poorly crystalline Fe and Mn oxides, and that added P is primarily associated with Fe oxide phases. Comparisons of pore water Pb concentrations with chloropyromorphite and plumbogummite solubility suggest that in the phosphate-amended soils the pore waters are undersaturated in these phases, whereas several of the control soil pore waters were oversaturated, indicating the added phosphate suppressed the Pb solubility. Results from this research provide insight into the geochemistry occurring in the P-remediated soils that will help in making management and remediation decisions.

Strawn, Daniel G.; Hickey, Patrick; Knudsen, Andrew; Baker, Leslie

2007-03-01

245

TREATMENT OF CONTAMINATED SOILS WITH AQUEOUS SURFACTANTS  

EPA Science Inventory

The overall objective of the project was to develop a technical base for decisions on the use of chemical countermeasures at releases of hazardous substances. Work included a literature search to determine the nature and quantities of contaminants at Superfund sites and the appli...

246

Remediation of Contaminated Soils By Supercritical Carbon Dioxide Extraction  

NASA Astrophysics Data System (ADS)

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 superficial velocity of the supercritical carbon dioxide; therefore, the mass transfer resistance can be reduced increasing such velocity. In this work, higher values of superficial velocity were investigated. The experimental apparatus includes a pump, an extraction vessel, an adjustable restrictor and a trap to collect the extracted substance. Liquid carbon dioxide coming from a cylinder with a dip-tube is cooled by a cryostatic bath and then it is compressed by a pneumatic drive pump (the max- imum available pressure is 69 MPa). Subsequently, the pressurised current flows into 1 a heating coil and then into the extraction vessel, which is contained in a stove; the outlet flow is depressurised in an adjustable restrictor and the extracted substance is collected in a trap by dissolution into a solvent. The extracted naphthalene quantity was obtained by weighting the solvent and measuring the naphthalene concentration with a gas chromatograph. The soil sample is a sandy soil geologically representative of the North of Italy that was sampled and physically and chemically characterized: particle-size distribution analysis, diffractometric analysis, Cation Exchange Capac- ity, Total Organic Carbon, iron content and manganese content in order to evaluate the potential sorption degree. The soil was artificially polluted by means of a naphta- lene and methylene chloride solution. The experimental work consists in a number of naphthalene extractions from the spiked soil, that were carried out at different operat- ing conditions, temperature, pressure and flow rate by means of supercritical carbon dioxide evaluating the corresponding recovery efficiencies. The results obtained were analysed and compared in order to determine which parameters influence the system. [1] G. A. Montero, T.D. Giorgio, and K. B. Schnelle, Jr..Removal of Hazardous ,1994, Contaminants form Soils by Supercritical Fluid Extraction. Innovations in Supercriti- cal Fluids. ACS Symposium Series, 608, 280-197. 2

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

247

Technical basis for EPA's proposed regulation on the cleanup of sites contaminated with radioactivity.  

PubMed

The U.S. Environmental Protection Agency is proposing a regulation for the protection of the public from radioactive contamination at sites that are to be cleaned up and released for public use. The rule will apply to sites under the control of Federal agencies, and will impose limits on radiation doses to individuals living or working on a site following cleanup; it will thereby provide site owners and managers with uniform, consistent cleanup criteria for planning and carrying out remediation. This paper presents an overview of EPA's approach to assessing some of the beneficial and adverse effects associated with various possible values for the annual dose limit. In particular, it discusses the method developed to determine how the choice of cleanup criterion affects (1) the time-integrated potential numbers of non-fatal and fatal radiogenic cancers averted among future populations, (2) the occurrence of radiogenic cancers among remediation workers and the public caused by the cleanup process itself, and (3) the volumes of contaminated soil that may require remediation. The analytic methods described here were used to provide input data and assumptions for the Regulatory Impact Analysis (RIA) that supports the proposed regulation; the RIA also considered non-radiological benefits and costs (i.e., public health, economic, and ecological) of the standards. PMID:8887509

Wolbarst, A B; Mauro, J; Anigstein, R; Back, D; Bartlett, J W; Beres, D; Chan, D; Clark, M E; Doehnert, M; Durman, E; Hay, S; Hull, H B; Lailas, N; MacKinney, J; Ralston, L; Tsirigotis, P L

1996-11-01

248

Decontamination and decommissioning of the Argonne National Laboratory East Area radioactively contaminated surplus facilities: Final report  

SciTech Connect

ANL has decontaminated and decommissioned (D and D) seven radiologically contaminated surplus facilities at its Illinois site: a ''Hot'' Machine Shop (Building 17) and support facilities; Fan House No. 1 (Building 37), Fan House No. 2 (Building 38), the Pangborn Dust Collector (Building 41), and the Industrial Waste Treatment Plant (Building 34) for exhaust air from machining of radioactive materials. Also included were a Nuclear Materials Storage Vault (Building 16F) and a Nuclear Research Laboratory (Building 22). The D and D work involved dismantling of all process equipment and associated plumbing, ductwork, drain lines, etc. After radiation surveys, floor and wall coverings, suspended ceilings, room partitions, pipe, conduit and electrical gear were taken down as necessary. In addition, underground sewers were excavated. The grounds around each facility were also thoroughly surveyed. Contaminated materials and soil were packaged and shipped to a low-level waste burial site, while nonactive debris was buried in the ANL landfill. Clean, reusable items were saved, and clean metal scrap was sold for salvage. After the decommissioning work, each building was torn down and the site relandscaped. The project was completed in 1985, ahead of schedule, with substantial savings.

Kline, W.H.; Fassnacht, G.F.; Moe, H.J.

1987-07-01

249

Radionuclide contaminated soil: Laboratory study and economic analysis of soil washing. Final report  

SciTech Connect

The objective of the work discussed in this report is to determine if soil washing is a feasible method to remediate contaminated soils from the Hazardous Waste Management Facility (HWMF) at Brookhaven National Laboratory (BNL). The contaminants are predominantly Cs-137 and Sr-90. The authors have assumed that the target activity for Cs-137 is 50 pCi/g and that remediation is required for soils having greater activities. Cs-137 is the limiting contaminant because it is present in much greater quantities than Sr-90. This work was done in three parts, in which they: estimated the volume of contaminated soil as a function of Cs-137 content, determined if simple removal of the fine grained fraction of the soil (the material that is less than 0.063 mm) would effectively reduce the activity of the remaining soil to levels below the 50 pCi/g target, assessed the effectiveness of chemical and mechanical (as well as combinations of the two) methods of soil decontamination. From this analysis the authors were then able to develop a cost estimate for soil washing and for a baseline against which soil washing was compared.

Fuhrmann, M.; Zhou, H.; Patel, B.; Bowerman, B.; Brower, J.

1996-05-20

250

DEMONSTRATION BULLETIN: HYDRAULIC FRACTURING OF CONTAMINATED SOIL  

EPA Science Inventory

Hydraulic fracturing is a physical process that creates fractures in silty clay soil to enhance its permeability. The technology, developed by the Risk Reduction Engineering Laboratory (RREL) and the University of Cincinnati, creates sand-filled horizontal fractures up to 1 in. i...

251

Role of soil rhizobacteria in phytoremediation of heavy metal contaminated soils*  

PubMed Central

Heavy metal pollution of soil is a significant environmental problem and has its negative impact on human health and agriculture. Rhizosphere, as an important interface of soil and plant, plays a significant role in phytoremediation of contaminated soil by heavy metals, in which, microbial populations are known to affect heavy metal mobility and availability to the plant through release of chelating agents, acidification, phosphate solubilization and redox changes, and therefore, have potential to enhance phytoremediation processes. Phytoremediation strategies with appropriate heavy metal-adapted rhizobacteria have received more and more attention. This article paper reviews some recent advances in effect and significance of rhizobacteria in phytoremediation of heavy metal contaminated soils. There is also a need to improve our understanding of the mechanisms involved in the transfer and mobilization of heavy metals by rhizobacteria and to conduct research on the selection of microbial isolates from rhizosphere of plants growing on heavy metal contaminated soils for specific restoration programmes. PMID:17323432

Jing, Yan-de; He, Zhen-li; Yang, Xiao-e

2007-01-01

252

INFLUENCE OF SILAGE CONTAMINATION BY SOIL UPON TRACE ELEMENTS AVAILABILITY IN SHEEP  

E-print Network

) of soil. The soil was an acid brown soil issued from granit rocks alteration. It was air dried, passedINFLUENCE OF SILAGE CONTAMINATION BY SOIL UPON TRACE ELEMENTS AVAILABILITY IN SHEEP M. LAMAND. Soil contaminations are not uncommon in silage and some harvesting machine are known to cause

Paris-Sud XI, Université de

253

Phytoremediation of uranium-contaminated soils: Role of organic acids in triggering uranium hyperaccumulation in plants  

Microsoft Academic Search

Uranium phytoextraction, the use of plants to extract U from contaminated soils, is an emerging technology. The authors report on the development of this technology for the cleanup of U-contaminated soils. In this research, they investigated the effects of various soil amendments on U desorption from soil to soil solution, studied the physiological characteristics of U uptake and accumulation in

Jianwei W. Huang; Michael J. Blaylock; Yoram Kapulnik; Burt D. Ensley

1998-01-01

254

Use of Carboxymethyl-beta-cyclodextrin (CMCD) as Flushing Agent for Remediation of Metal Contaminated Soil  

NASA Astrophysics Data System (ADS)

One of the major challenges in remediating soil and ground water is the presence of mixed organic and inorganic contaminants. Due to their very different behavior, research has to a large extent focused on remediation of either organic or inorganic contaminants rather than mixed waste. Cyclodextrins (CDs) are a group of non-toxic sugar based molecules that do not sorb to soil particles and do not experience pore size exclusion. Thus, they have good hydraulic properties. CDs enhance the solubility of organic compounds by forming inclusion complexes between organic contaminants and the non-polar cavity at the center of the CD. By substituting functional groups to the cyclodextrin molecule it can form complexes with heavy metals. Previous studies have shown that carboxymethyl-beta-cyclodextrin (CMCD) can simultaneously complex organic and inorganic contaminants. The aim of this study is to compare how strongly CMCD complexes several common heavy metals, radioactive elements and a common divalent cation. Results from batch experiments show that CMCD has the ability to complex a wide array of heavy metals and radioactive elements. The solubility of metal oxalates and metal oxides clearly increased in the presence of CMCD. Logarithmic conditional formation constants ranged from 3.5 to 6 for heavy metals and from 3 to 6 for radioactive elements. Calcium, which may compete for binding sites, has a logarithmic conditional formation constant of 3.1. Batch experiments performed at 10 and 25 degrees C showed little temperature effect on conditional formation constants. Results from batch experiments were compared to results from column experiments where Pb was sorbed onto hydrous ferric oxide coated sand and subsequently removed by a CMCD solution. The results indicate that CMCD is a potential flushing agent for remediation of mixed waste sites.

Skold, M. E.; Thyne, G. D.; McCray, J. E.; Drexler, J. W.

2005-12-01

255

Radioactive contaminant characterization and measurements of residual radioactivity in the TMI2 auxiliary and fuel handling buildings and reactor building  

Microsoft Academic Search

One consequence of the Three Mile Island Unit 2 (TMI-2) accident was the widespread radioactive contamination of the auxiliary and fuel-handling buildings (AFHB) and the reactor building (RB). These areas required extraordinary decontamination efforts to achieve the cleanup program objectives. On completion of cleanup activities (including decontamination) in a given area or cubicle, the area was isolated to minimize uncontrolled

G. M. Lodde; A. F. Paynter; B. A. Brosey

1994-01-01

256

Phytoremediation of contaminated soils and groundwater: lessons from the field  

SciTech Connect

The use of plants and associated microorganisms to remove, contain, inactivate, or degrade harmful environmental contaminants (generally termed phytoremediation) and to revitalize contaminated sites is gaining more and more attention. In this review, prerequisites for a successful remediation will be discussed. The performance of phytoremediation as an environmental remediation technology indeed depends on several factors including the extent of soil contamination, the availability and accessibility of contaminants for rhizosphere microorganisms and uptake into roots (bioavailability), and the ability of the plant and its associated microorganisms to intercept, absorb, accumulate, and/or degrade the contaminants. The main aim is to provide an overview of existing field experience in Europe concerning the use of plants and their associated microorganisms whether or not combined with amendments for the revitalization or remediation of contaminated soils and undeep groundwater. Contaminations with trace elements (except radionuclides) and organics will be considered. Because remediation with transgenic organisms is largely untested in the field, this topic is not covered in this review. Brief attention will be paid to the economical aspects, use, and processing of the biomass. It is clear that in spite of a growing public and commercial interest and the success of several pilot studies and field scale applications more fundamental research still is needed to better exploit the metabolic diversity of the plants themselves, but also to better understand the complex interactions between contaminants, soil, plant roots, and microorganisms (bacteria and mycorrhiza) in the rhizosphere. Further, more data are still needed to quantify the underlying economics, as a support for public acceptance and last but not least to convince policy makers and stakeholders (who are not very familiar with such techniques).

Vangronsveld, J.; van der Lelie, D.; Herzig, R.; Weyens, N.; Boulet, J.; Adriaensen, K.; Ruttens, A.; Thewys, T.; Vassilev, A.; Meers, E.; Nehnevajova, E.; Mench, M.

2009-11-01

257

Imaging plant leaves to determine changes in radioactive contamination status in Fukushima, Japan.  

PubMed

The chemical composition of plant leaves often reflects environmental contamination. The authors analyzed images of plant leaves to investigate the regional radioactivity ecology resulting from the 2011 accident at the Fukushima No. 1 nuclear power plant, Japan. The present study is not an evaluation of the macro radiation dose per weight, which has been performed previously, but rather an image analysis of the radioactive dose per leaf, allowing the capture of various gradual changes in radioactive contamination as a function of elapsed time. In addition, the leaf analysis method has potential applications in the decontamination of food plants or other materials. PMID:24670905

Nakajima, Hiroo; Fujiwara, Mamoru; Tanihata, Isao; Saito, Tadashi; Matsuda, Norihiro; Todo, Takeshi

2014-05-01

258

Modeling the atmospheric transport of radioactive contamination using the ETA model  

SciTech Connect

The atmosphere is the main medium that transports and disperses the radioactive and/or chemical contaminants in operational use and in accidents. Atmospheric models can be used to simulate the transport of contaminants in typical accidents and for realistic meteorological conditions. This paper describes an approach to simulating the Chernobyl accident and similar hypothetical cases. The study is based on an atmospheric model extended by an additional equation that models the transport of a certain radioactive concentration. A step mountain synoptic model, called the ETA model (well-known model for weather forecasting), is used to investigate the transport and deposition of radioactive material in the Chernobyl accident zone.

Telenta, B. [ICSC World Laboratory, Erice (Italy); Antic, D. [Inst. of Nuclear Sciences Vinca, Belgrade (Yugoslavia)

1996-12-31

259

BIOREMEDIATION OF EXPLOSIVES- CONTAMINATED SOILS: A STATUS REVIEW  

Microsoft Academic Search

The investigation of past operational and disposal practices at federal facilities and formerly used defense sites (FUDS) has dramatically increased in the past several years. The manufacture; load, assembly and pack (LAP); demilitarization; washout operations; and open burn\\/open detonation (OB\\/OD) of ordnance and explosives has resulted in contamination of soils with munitions residues. The primary constituents are nitroaromatic and nitramine

H. D. Craig; W. E. Sisk; M. D. Nelson; W. H. Dana

260

SUPERFUND ENGINEERING ISSUE: TREATMENT OF LEAD-CONTAMINATED SOILS  

EPA Science Inventory

This document summarizes the contents of a seminar on treatment of lead-contaminated soils presented on August 28, 1990, to Region V Superfund and RCRA personnel by members of EPA's Engineering and Treatment Technology Support Center located in the Risk Reduction Engineering Labo...

261

USING PLANTS TO REMEDIATE PETROLEUM-CONTAMINATED SOIL: PROJECT CONTINUATION  

EPA Science Inventory

Crude oil contamination of soil often occurs adjacent to wellheads and storage facilities. Phytoremediation is a promising tool that can be used to remediate such sites and uses plants and agronomic techniques to enhance biodegradation of hydrocarbons. This project has conduct...

262

DERMAL ABSORPTION OF CONTAMINANTS FROM SEDIMENTS/SOILS  

EPA Science Inventory

The mechanisms by which contaminants are released from sediments/soils and absorbed into the skin are poorly understood. The project will first conduct invitro experiments to study the effects of particle layering and chemical saturation. Secondly, mechanistic models will be de...

263

Chemical methods and phytoremediation of soil contaminated with heavy metals.  

PubMed

The effects of chemical amendments (calcium carbonate (CC), steel sludge (SS) and furnace slag (FS)) on the growth and uptake of cadmium (Cd) by wetland rice, Chinese cabbage and wheat grown in a red soil contaminated with Cd were investigated using a pot experiment. The phytoremediation of heavy metal contaminated soil with vetiver grass was also studied in a field plot experiment. Results showed that treatments with CC, SS and FS decreased Cd uptake by wetland rice, Chinese cabbage and wheat by 23-95% compared with the unamended control. Among the three amendments, FS was the most efficient at suppressing Cd uptake by the plants, probably due to its higher content of available silicon (Si). The concentrations of zinc (Zn), lead (Pb) and Cd in the shoots of vetiver grass were 42-67%, 500-1200% and 120-260% higher in contaminated plots than in control, respectively. Cadmium accumulation by vetiver shoots was 218 g Cd/ha at a soil Cd concentration of 0.33 mg Cd/kg. It is suggested that heavy metal-contaminated soil could be remediated with a combination of chemical treatments and plants. PMID:10819205

Chen, H M; Zheng, C R; Tu, C; Shen, Z G

2000-07-01

264

AN ESTIMATE OF SOILS CONTAMINATED WITH SECONDARY EXPLOSIVES  

EPA Science Inventory

This report provides the results of a study that examined the quantities of explosives-contaminated soils at Army installations in the United States in order to understand the user requirements for environmental technology research and development work. This report provides a tim...

265

APPLICATION, PERFORMANCE, AND COSTS OF BIOTREATMENT TECHNOLOGIES FOR CONTAMINATED SOILS  

EPA Science Inventory

A critical review of biological treatment processes for remediation of contaminated soils is presented. The focus of the review is on documented cost and performance of biological treatment technologies demonstrated at full- or field-scale. Some of the data were generated b...

266

TREATING PETROLEUM CONTAMINATED SOIL AND SLUDGES USING PLASMA  

Microsoft Academic Search

Traditional processes, such as incineration, cement kiln processing, centrifuging and others, used for treating soil contaminated with petroleum, oil, diesel, etc and or for treating oily sludges (generated from the exploration, production and refining of petroleum), present several environmental, technical and economical restrictions. A new process, based on the use of a plasma system, was developed for treating those materials,

R. N. Szente; L. B. Souza; H. Pasquini

267

HANDBOOK ON IN SITU TREATMENT OF HAZARDOUS WASTE- CONTAMINATED SOILS  

EPA Science Inventory

This handbook comprises an update of Volume1 of the 1984 USEPA document entitled "Review of In-Place Treatment Techniques for Contaminated Surface Soils." The purpose of this handbook is the same as that of the original document - to provide state-of-the-art information on in sit...

268

Chemical Extraction of Arsenic from Contaminated Soil  

Microsoft Academic Search

A series of batch extraction experiments were conducted using a fortified soil with different extracting solutions such as inorganic acids (hydrochloric acid (HCl), sulfuric acid (H2SO4), phosphoric acid (H3PO4), perchloric acid (HClO4), or nitric acid (HNO3)), organic acids (acetic acid (C2H4O2), citric acid (C6H8O7)) and alkaline agent (NaOH). Various concentrations were used to investigate the removal efficiency and to optimise

M. G. M. ALAM; S. TOKUNAGA

2006-01-01

269

Phytoremediation: Using green plants to clean up contaminated soil, groundwater, and wastewater  

SciTech Connect

Phytoremediation, an emerging cleanup technology for contaminated soils, groundwater, and wastewater that is both low-tech and low-cost, is defined as the engineered use of green plants (including grasses, forbs, and woody species) to remove, contain, or render harmless such environmental contaminants as heavy metals, trace elements, organic compounds ({open_quotes}organics{close_quotes}), and radioactive compounds in soil or water. Current research at Argonne National Laboratory includes a successful field demonstration of a plant bioreactor for processing the salty wastewater from petroleum wells; the demonstration is currently under way at a natural gas well site in Oklahoma, in cooperation with Devon Energy Corporation. A greenhouse experiment on zinc uptake in hybrid poplar (Populus sp.) was initiated in 1995. These experiments are being conducted to confirm and extend field data from Applied Natural Sciences, Inc. (our CRADA partner), indicating high levels of zinc (4,200 ppm) in leaves of hybrid poplar growing as a cleanup system at a site with zinc contamination in the root zone of some of the trees. Analyses of soil water from experimental pots that had received several doses of zinc indicated that the zinc was totally sequestered by the plants in about 4 hours during a single pass through the root system. The data also showed concentrations of sequestered metal of >38,000 ppm Zn in the dry root tissue. These levels of sequestered zinc exceed the levels found in either roots or tops of many of the known {open_quotes}hyperaccumulator{close_quotes} species. Because the roots sequester most of the contaminant taken up in most plants, a major objective of this program is to determine the feasibility of root harvesting as a method to maximize the removal of contaminants from soils. Available techniques and equipment for harvesting plant roots, including young tree roots, are being evaluated and modified as necessary for use with phytoremediation plants.

Negri, M.C.; Hinchman, R.R.

1996-05-01

270

Metal ion leaching from contaminated soils: Model development  

SciTech Connect

A mathematical model is developed for metal leaching from contaminated soils subjected to acid extraction in a batch reactor. The model considers transport by pore diffusion and film transfer, leaching of metal bound to reversible and irreversible phases, and metal complexation by ions in solution. As currently developed, the model is semiempirical, with the primary objective of exploring the relative significance of chemical kinetics and diffusional transport under acidic leaching conditions. Simulation results and sensitivity analyses show that leaching kinetics vary according to the metal binding mechanism and location with a soil particle. The effects of pH, pore diffusion, film transfer, chemical reaction rate, particle size, and initial metal distribution are examined using parameter estimates derived from experimental data for a hazardous-waste-site soil contaminated with lead. Depending on leaching conditions, diffusion, reaction, or both may control metal leaching for time-scales of interest in soil washing. Both the distribution of contaminant metal between the reversibly and irreversibly sorbed fractions and the initial spatial distribution within the soil particle are important in determining leaching behavior.

Ganguly, C.; Rabideau, A.J.; Benschoten, J.E. Van [Univ. of New York, Buffalo, NY (United States). Dept. of Civil Engineering; Matsumoto, M.R. [Univ. of California, Riverside, CA (United States). College of Engineering

1998-03-01

271

Changes in the structure and function of soil ecosystems in soils contaminated with heavy metals  

SciTech Connect

The structure and function of soil communities in an area with a wide range of concentrations of heavy metals was studied in portions of the U.S. Army`s Aberdeen Proving Ground, Maryland. The study included survey of soil macro- and microinvertebrate communities, soil microorganisms, enzyme activities and the rates of nutrient dynamics in soil. Soil macroinvertebrate communities showed significant reductions in the adundance of several taxonomic and functional groups in contaminated areas. The total numbers of nematodes and numbers of fungivore, bacterivore and omnivore-predator nematodes were lower in the more contaminated areas. The numbers of active bacteria and fungi were lower in areas of soil contamination. Significant reduction in the activities of all enzymes closely paralleled the increase in heavy metal concentrations. Ten-to-fifty fold reductions in enzyme activities were observed as heavy metal concentrations increased. These results suggest that soil contamination with heavy metals may have detrimental effects on soil biota and the rates of organic matter degradation and subsequent release of nutrients to aboveground communities in the area.

Kuperman, R.; Parmelee, R.; Carreiro, M. [Argonne National Laboratory, IL (United States)]|[Ohio State Univ., Columbus, OH (United States)]|[Fordham Univ. Armonk, NY (United States)

1995-09-01

272

Changes in the structure and function of soil ecosystems in soils contaminated with heavy metals  

SciTech Connect

The structure and function of soil communities in an area with a wide range of concentrations of heavy metals was studied in portions of the U.S. Army`s Aberdeen Proving Ground, Maryland. The study included survey of soil macro- and microinvertebrate communities, soil microorganisms, enzyme activities and the rates of nutrient dynamics in soil. Soil macroinvertebrate communities showed significant reductions in the abundance of several taxonomic and functional groups in contaminated areas. The total numbers of nematodes and numbers of fungivore, bacterivore and omnivore-predator nematodes were lower in the more contaminated areas. The numbers of active bacteria and fungi were lower in areas of soil contamination. Significant reduction in the activities of all enzymes closely paralleled the increase in heavy metal concentrations. Ten-to-fifty fold reductions in enzyme activities were observed as heavy metal concentrations increased. These results suggest that soil contamination with heavy metals may have detrimental effects on soil biota and the rates of organic matter degradation and subsequent release of nutrients to aboveground communities in the area.

Kuperman, R.; Parmelee, R.; Carreiro, M. [Argonne National Lab., IL (United States)]|[Ohio State Univ., Columbus, OH (United States)]|[Fordham Univ., Armonk, NY (United States)

1995-06-01

273

EFFECT OF SOIL MODIFYING FACTORS ON THE BIOAVAILABILITY AND TOXICITY OF METAL CONTAMINATED SOILS  

EPA Science Inventory

Heavy metal and organic chemical contamination of soils is a worldwide problem posing a risk to humans and more directly, soil organisms. Metal toxicity is often not directly related to the total concentration of metals present due to a number of modifying factors that depend,...

274

Geochemistry Of Lead In Contaminated Soils: Effects Of Soil PhysicoChemical Properties  

Microsoft Academic Search

Lead (Pb) is an environmental contaminant with proven human health effects. When assessing human health risks associated with Pb, one of the most common exposure pathways typically evaluated is soil ingestion by children. However, bioaccessibility of Pb primarily depends on the solubility and hence, the geochemical form of Pb, which in turn is a function of site specific soil chemistry.

S. Saminathan; D. Sarkar; R. Datta; S. P. Andra

2006-01-01

275

Influence of organic and inorganic soil amendments on plant growth in crude oil?contaminated soil  

Microsoft Academic Search

Phytoremediation can be a viable alternative to traditional, more costly remediation techniques. Three greenhouse studies were conducted to evaluate plant growth with different soil amendments in crude oil?contaminated soil. Growth of alfalfa (Medicago sativa L., cultivar: Riley), bermudagrass (Cynodon dactylon L., cultivar: Common), crabgrass (Digitaria sanguinalis cultivar: Large), fescue (Lolium arundinaceum Schreb., cultivar: Kentucky 31), and ryegrass (Lolium multiflorum Lam.,

P. M. White Jr; D. C. Wolf; G. J. Thoma; C. M. Reynolds

2003-01-01

276

Transport of PCBs with leachate water from contaminated soil.  

PubMed

Natural soil contaminated with PCBs was used in this study. The soil was excavated from the area around the damaged capacitor of an electrical transformer station in Zadar (ETS 110/35 kV). A lysimeter experiment was conducted for 17 months under natural climatic conditions and designed to measure the concentration of PCB in the soil and leachates. Our research field was composed of four plots and there were three lysimeters on each plot. After 12 months, a negligible quantity of Aroclor 1248 (an average of 0.24%) and the Sigma 7 key PCB congeners (SigmaPCB(7); IUPAC No.: PCB 28, PCB 52, PCB 101, PCB 118, PCB 138, PCB 153 and PCB 180) were leached from the soils into the water collected under the lysimeters (an average of 0.32%). During two soil samplings, the soil was taken at three depths from each lysimeter. The distribution of Aroclor 1248 and 7 individual PCB congeners in the soil layers was determined before and after planting. Plot No. 1 had the highest percentage of contaminant removal after 12 months. The data indicate that the Sigma 7 key PCBs in the surface soil layers of all the plots decreased and the removal percentages ranged between 19.0% (Plot No. 2) and 47.6% (Plot No. 1). Volatilization from the soil surface may be the most important mechanism for the loss of these "more volatile" PCB congeners. The results showed an accumulation of PCBs in the deepest level of the soil plots, probably due to the vertical transfer of the PCBs and the lack of volatilization. PMID:18440045

Kobasi?, Vedranka Hodak; Picer, Mladen; Picer, Nena; Cali?, Violeta

2008-08-01

277

Gypsum addition to soils contaminated by red mud: Implications for aluminium, arsenic, molybdenum and vanadium solubility.  

E-print Network

Gypsum addition to soils contaminated by red mud: Implications for aluminium, arsenic, molybdenum. 4 Department of Applied Biotechnology and Food Science, Budapest University of Technology, contaminated soils, gypsum, toxic trace elements, arsenic, vanadium, aluminium, organic matter leaching, p

Burke, Ian

278

EVALUATION OF SOLIDIFICATION/STABILIZATION AS A BEST DEMONSTRATED AVAILABLE TECHNOLOGY FOR CONTAMINATED SOILS  

EPA Science Inventory

This project involved the evaluation of solidification/stabilization technology as a BDAT for contaminated soil. Three binding agents were used on four different synthetically contaminated soils. Performance evaluation data included unconfined compressive strength (UCS) and the T...

279

Assessing the bioavailability and risk from metal-contaminated soils and dusts  

EPA Science Inventory

Exposure to contaminated soil and dust is an important pathway in human health risk assessment. Physical and chemical characteristics, as well as biological factors, determine the bioaccessibility/bioavailability of soil and dust contaminants. Within a single sample, contaminat...

280

Heavy metals contamination of soils surrounding waste deposits in Romania  

NASA Astrophysics Data System (ADS)

Soils contamination with heavy metals is one of the most severe aspects of environmental pollution in Romania, independently of the origin sources (domestic or industrial activities) or type of disposal (organised landfill or hazardous deposits)[l-2]. This fact is the consequence of the poor state of the existing waste deposits in Romania and of the significant costs involved by the establishing of a new landfill according with the international regulations. The present study is trying to emphasise the contamination of soils surrounding different categories of waste deposits (sewage sludge ponds, domestic and industrial waste landfills, hillocks, sterile deposits) from various regions of Romania. Some case studies show a special interest being localise in a protected area (Iron Gates Natural Park). In order to quantify the concentration of metals like Cd, Cr, Cu, Pb, Zn, Ni, Mo in soil samples, analysis were performed using Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES). Romanian standards were used as reference values[3].

Matache, M.; Rozylowicz, L.; Ropota, M.; Patroescu, C.

2003-05-01

281

Phytoremediation of heavy metal contaminated soil by Jatropha curcas.  

PubMed

This study employed Jatropha curcas (bioenergy crop plant) to assist in the removal of heavy metals from contaminated field soils. Analyses were conducted on the concentrations of the individual metals in the soil and in the plants, and their differences over the growth periods of the plants were determined. The calculation of plant biomass after 2 years yielded the total amount of each metal that was removed from the soil. In terms of the absorption of heavy metal contaminants by the roots and their transfer to aerial plant parts, Cd, Ni, and Zn exhibited the greatest ease of absorption, whereas Cu, Cr, and Pb interacted strongly with the root cells and remained in the roots of the plants. J. curcas showed the best absorption capability for Cd, Cr, Ni, and Zn. This study pioneered the concept of combining both bioremediation and afforestation by J. curcas, demonstrated at a field scale. PMID:25236867

Chang, Fang-Chih; Ko, Chun-Han; Tsai, Ming-Jer; Wang, Ya-Nang; Chung, Chin-Yi

2014-12-01

282

[Bio-remediation techniques of crude oil contaminated soils].  

PubMed

The bioremediation of soils contaminated by different types of petroleum were carried out with composting process in a prepared bed. By the measures of nutrient- and microbiological agent addition, and moisture- and pH control, an ideal environment for microbes were obtained. When total petroleum hydrocarbons, which consist of thin oil, high condensation oil, special viscous oil, and viscous oil, were in the range of 25.8-77.2 g.kg-1 dry soil, the petroleum removal rate could reach 38.37-56.74% by 2 months operation. The contents of aromatic hydrocarbon, asphaltum and resin were important factors controlling the degradation of petroleum. 6 fungi, 6 bacteria and 1 actinomyces were found to be the dominant strains for petroleum degradation. The results could provide theoretical bases for remediation of soil contaminated by petroleum. PMID:12625007

Li, Peijun; Guo, Shuhai; Sun, Tieheng; Tai, Peidong; Zhang, Chungui; Bai, Yuxing; Sun, Qiang; Sheng, Ping

2002-11-01

283

Identifying root exudates in field contaminated soil systems  

NASA Astrophysics Data System (ADS)

Carbon (C) compounds exuded from plant roots comprise a significant and reactive fraction of belowground C pools. These exudates substantially alter the soil directly surrounding plant roots and play a vital role in the global C cycle, soil ecology, and ecosystem mobility of both nutrients and contaminants. In soils, the solubility and bioavailability of metals such as iron, zinc, and cadmium are intricately linked to the quantity and chemical characteristics of the C compounds allocated to the soil by plants. Cadmium (Cd), a toxic heavy metal, forms stronger bonds with reduced S- and N-containing compounds than with carboxylic acids, which may influence exudate composition in hyperaccumulator and tolerant plants grown in Cd contaminated soils. We hypothesize that hyperaccumulator plants will exude a larger quantity of aromatic N and chelating di- and tri-carboxylic acid molecules, while plants that exclude heavy metals from uptake will exude a larger proportion of reduced S containing molecules. This study examines how a variety of techniques can measure the low concentrations of complex organic mixtures exuded by hyperaccumulator and non-hyperaccumulator plants grown in Cd-contaminated soils. Two congeneric plants, Thlaspi caerulescens (Ganges ecotype), and T. caerulescens (Prayon ecotype) were grown in 0.5 kg pots filled with Cd-contaminated field soils from Chicago, IL. Field soils were contaminated as a result of the application of contaminated biosolids in the 1960's and 1970's. Pots were fitted for rhizon soil moisture samplers, micro-lysimeters developed for in situ collection of small volumes in unsaturated soils, prior to planting. Plants were grown for 8 weeks before exudate collection. After the 8 weeks of growth, a pulse-chase isotope tracer method using the C stable isotope, 13C, was employed to differentiate plant-derived compounds from background soil and microbial-derived compounds. Plants were placed in a CO2 impermeable chamber, and the soil surface was covered by CO2 impermeable sheets to ensure that all 13C in the soil results from photoassimilated C released by roots and not soil-atmosphere gas exchange. Ambient CO2 was drawn down in the system until the CO2 concentration within the tent was less than 50 ppm, after which the labeled 13CO2 was introduced, returning the CO2 concentration to the ambient level (~375 ppm). The CO2 pulse lasted for 60 minutes to allow enough time for 13C assimilation within the plants. In order to determine the ideal sampling time, soil pore water samples were extracted every 1-2 hours following the 13C pulse application, over the course of 24 hours. Samples were analyzed for delta 13C as well as %C, and results indicate that the greatest plant-derived dissolved organic C is present at about 6 hours following the 13C pulse. A second experiment will also be conducted using a combination of NMR and mass spectrometry methods to obtain detailed information regarding chemical structures within exudate samples.

Rosenfeld, C.; Martinez, C. E.

2012-12-01

284

Soil slurry reactors for the assessment of contaminant biodegradation  

NASA Astrophysics Data System (ADS)

Slurry reactors are frequently used in the assessment of feasibility of biodegradation in natural soil systems. The rate of contaminant removal is usually quantified by zero- or first-order kinetics decay constants. The significance of such constants for the evaluation of removal rate in the field could be questioned because the slurry reactor is a water-saturated, well-stirred system without resemblance with an unsaturated fixed bed of soil. Nevertheless, a kinetic study with soil slurry reactors can still be useful by means of only slightly more sophisticated kinetic models than zero-/first-order decay. The use of kinetic models taking into account the role of degrading biomass, even in the absence of reliable experimental methods for its quantification, provides further insight into the effect of nutrient additions. A real acceleration of biodegradation processes is obtained only when the degrading biomass is in the growth condition. The apparent change in contaminant removal course can be useful to diagnose biomass growth without direct biomass measurement. Even though molecular biology techniques are effective to assess the presence of potentially degrading microorganism in a "viable-but-nonculturable" state, the attainment of conditions for growth is still important to the development of enhanced remediation techniques. The methodology is illustrated with reference to data gathered for two test sites, Oslo airport Gardermoen in Norway (continuous contamination by aircraft deicing fluids) and the Trecate site in Italy (aged contamination by crude oil spill). This research is part of SoilCAM project (Soil Contamination, Advanced integrated characterisation and time-lapse Monitoring 2008-2012, EU-FP7).

Toscano, G.; Colarieti, M. L.; Greco, G.

2012-04-01

285

Electrokinetic remediation of six emerging organic contaminants from soil.  

PubMed

Some organic contaminants can accumulate in organisms and cause irreversible damages in biological systems through direct or indirect toxic effects. In this study the feasibility of the electrokinetic (EK) process for the remediation of 17?-oestradiol (E2), 17?-ethinyloestradiol (EE2), bisphenol A (BPA), nonylphenol (NP), octylphenol (OP) and triclosan (TCS) in soils was studied in a stationary laboratory cell. The experiments were conducted using a silty loam soil (S2) at 0, 10 and 20mA and a sandy soil (S3) at 0 and 10mA. A pH control in the anolyte reservoir (pH>13) at 10mA was carried out using S2, too. Photo and electrodegradation experiments were also fulfilled. Results showed that EK is a viable method for the remediation of these contaminants, both through mobilization by electroosmotic flow (EOF) and electrodegradation. As EOF is very sensible to soil pH, the control in the anolyte increased EOF rate, consequently enhancing contaminants mobilization towards the cathode end. The extent of the mobilization towards the electrode end was mainly dependent on compounds solubility and octanol-water partition coefficient. In the last 24h of experiments, BPA presented the highest mobilization rate (ca. 4?gmin(-1)) with NP not being detected in the catholyte. At the end of all experiments the percentage of contaminants that remained in the soil ranged between 17 and 50 for S2, and between 27 and 48 for S3, with no statistical differences between treatments. The mass balance performed showed that the amount of contaminant not detected in the cell is similar to the quantity that potentially may suffer photo and electrodegradation. PMID:24997283

Guedes, Paula; Mateus, Eduardo P; Couto, Nazaré; Rodríguez, Yadira; Ribeiro, Alexandra B

2014-12-01

286

Analytical procedures for measuring the amount and distribution of radioactive constituents in soils  

Microsoft Academic Search

For a research project on the evaluation and distribution of radioactive pollutants in Biscay's plants and soils, it was necessary to establish an analytical procedure to detect and measure extremely low amounts of radioactive elements. For the project 15 cm cores of fourteen soils were taken and divided into three depth levels. Some of these soil samples (<2 mm) were

C. Elejalde; M. Herranz; F. Romero; F. Legarda; E. Ruiz

1993-01-01

287

Multiscale structure of Cs-137 soil contamination on the Bryansk Region (Russia) due to the accident at the Chernobyl NPP  

NASA Astrophysics Data System (ADS)

The Cs-137 contamination of the Bryansk Region occurred in the period from April 27 to May 10 into several stages. The complicated character of the soil radionuclide contamination on the Bryansk Region is caused by different nature of the radioactive fallout: dry and wet. Thus, in a number of cases Cs-137 soil pollution is directly connected with the rain intensity, which is well known, have multifractal nature. In some parts of contaminated territory the overlay of different types of fallout was observed. The radioactive contamination of the landscape is a result from nonlinear interplay of geophysical factors which intervene over a large range of scale. As a result of the fallout Cs-137 pattern can be described as a multifractal. Consequently, fields of contamination observed have an extreme spatial variability, frequently cited "hot spots" or "leopard's skin. As an estimate of background radiation levels, we relied on a dataset of air-gamma-survey of the Bryansk Region, carried out by SSC AEROGEOFIZIKA in the summer of 1993. This dataset includes geo-positioned data of Cs-137 deposition in a grid of 100x100 m with values range from 3 to 11*104 kBq/m2. Airborne gamma survey gave the smoothed values of the Cs-137 density of contamination in comparison with the data, obtained directly as a result of soil sampling. However, even in this case in the east part of the Bryansk test site we can observed the"hot spots" (by size several hundred meters) as natural phenomenon. The article presents the results of the geostatistical and multifractal analysis of the Cs-137 contamination. Scaling analysis was conducted to investigate the linkages between the spatial variability of soil Cs-137 contamination and some landscape characteristics.

Linnik, Vitaly; Sokolov, Alexander

2013-04-01

288

[Therapeutic consequences of contamination injuries by highly radioactive substances].  

PubMed

A case of plutonium injury of the left hand is used to explain the correct management. In addition to radical surgical excision under repeated monitoring of radioactivity, it is obligatory to commence parenteral chelation therapy with DTPA. Close cooperation with radiological technologists is necessary. Discharges and used bandages have to be analysed for their radioactive content before elimination as radioactive waste. Isolation of the patient is not required. The relevant government department has to be contacted. A health center for radiation victims with special measuring equipment is desirable. PMID:2283111

Lennert, K H

1990-11-01

289

Heavy-metal contamination of soils in Saxony/Germany by foundry fumes and low-cost rapid analyses of contaminated soils by XRF  

NASA Astrophysics Data System (ADS)

Heavy-metal contamination of soils in Saxony/Germany by foundry fumes and low-cost rapid analysis of contaminated soils by XRF Dieter Mucke, Rolf Kumann, Sebastian Baldauf GEOMONTAN Gesellschaft für Geologie und Bergbau mbH&Co.KG, Muldentalstrasse 56, 09603 Rothenfurth, Saxony/Germany For hundreds of years in the Ore Mountains between Bohemia and Saxony silver and other ores are produced and smelted. Sulphide- and sulpharsenide-ores needed to be roasted first. In doing so the sulphide sulphur was oxidised under formation of sulphur dioxide SO2 and arsenide conversed into elemental arsenic and arsenide trioxide As2O3 respectively. Also the metals lead, cadmium and zinc are components of hut smokes, in the field of nickel foundries also nickel. The contents of soils basically reflect the geogenic conditions, which are caused by decomposition- and relocation-effects of the mineralisations, in the area of foundries also with influences by with the hut smokes anthropogenic mobilised elements. The Saxonian Agency for Environment and Geology drafted in 1992 a Soil Investigation Program with the aim of investigation of the contamination of Saxonian soils with arsenic and toxic heavy metals. In order of this Agency GEOMONTAN investigated 1164 measuring points in the grid 4 * 4 km.soil profiles and extracted soil samples for analysis. In the result of the laboratory examinations the Agency edited the "Soil atlas of the Free State of Saxony". 27 elements, pH and PAK are shown in detailed maps and allow in whole Saxony the first assessment of the contamination of soils with arsenic and toxic heavy metals. Each of the investigated soil profiles represent an area of 16 km2. Already by the different use of the districts (agricultural, industrial, urban) restricts representative values. GEOMONTAN in the meantime used at the exploration of a copper deposit in Brandenburg/Germany with approx. 50,000 single tests at drill cores a very fast low-cost method: the X Ray fluorescence spectrometry (XRF) with a handheld instrument. Approx. 40 elements hereby are determined in a focussed X-ray spot of 3 mm of diameters. The device can be put directly on a section of the soil or measure loose substrata in a PVC bag through or in a cuvette. The measurement time is 30 seconds. In connection with the input of information, the relocating and the sample preparation 20 measurings can be carried out per hour. This leads at personnel expenditures of € 50/hour at a price of € 2.50/analysis of simultaneous 40 components. At requirement the transfer of the files from the instrument in Excel tables still would rise expenses. XRF is a fast low-cost method for the first assessment of the contamination of soils and the delimitation of areas of different contaminations. When exact laboratory analyses are still requested, the interesting areas from which bulk samples have to be taken for the laboratory examinations, with XRF can be fixed. The contamination with arsenic and toxic heavy metals is only subordinated by modern flue gas treatment in metallurgical plants and renunciation of thermal methods with hut smoke today. The whereabouts of arsenic and lead in the soil shows, though, that the soil has protected the groundwater against the contamination. GEOMONTAN has examined the Saxonian areas with radioactive fallout of the Chernobyl accident in the order of the BGR Hannover 1993. In the results of the analysis by BGR Cs-134 was already disintegrated and Cs-137 only 13 cm deep in the uppermost soil layers infiltrated during the 8 years after the accident. This means that soil protects groundwater against contaminations out of the air too. In the last years some German federal state governments decided the end of mine water winning for the public water supply and deregulated the water protection zones. The water supply was converted in water of water supply dams. The hazard of contamination of this open reservoirs by accidents or terrorism is increasing. Underground water bodies in karst caves and old mines without toxic mineralizations would be

Mucke, D.

2012-04-01

290

Ecotoxicity of a polycyclic aromatic hydrocarbon (PAH)-contaminated soil.  

PubMed

Soil samples from a former cokery site polluted with polycyclic aromatic hydrocarbons (PAHs) were assessed for their toxicity to terrestrial and aquatic organisms and for their mutagenicity. The total concentration of the 16 PAHs listed as priority pollutants by the US Environmental Protection Agency (US-EPA) was 2634+/-241 mg/kgdw in soil samples. The toxicity of water-extractable pollutants from the contaminated soil samples was evaluated using acute (Vibrio fischeri; Microtox test, Daphnia magna) and chronic (Pseudokirchneriella subcapitata, Ceriodaphnia dubia) bioassays and the EC values were expressed as percentage water extract in the test media (v/v). Algal growth (EC50-3d=2.4+/-0.2% of the water extracts) and reproduction of C. dubia (EC50-7d=4.3+/-0.6%) were the most severely affected, compared to bacterial luminescence (EC50-30 min=12+/-3%) and daphnid viability (EC50-48 h=30+/-3%). The Ames and Mutatox tests indicated mutagenicity of water extracts, while no response was found with the umu test. The toxicity of the soil samples was assessed on the survival and reproduction of earthworms (Eisenia fetida) and collembolae (Folsomia candida), and on the germination and growth of higher plants (Lactuca sativa L.: lettuce and Brassica chinensis J.: Chinese cabbage). The EC50 values were expressed as percentage contaminated soil in ISO soil test medium (weight per weight-w/w) and indicated severe effects on reproduction of the collembola F. candida (EC50-28 d=5.7%) and the earthworm E. fetida (EC50-28 d=18% and EC50-56 d=8%, based on cocoon and juvenile production, respectively). Survival of collembolae was already affected at a low concentration of the contaminated soil (EC50-28 d=11%). The viability of juvenile earthworms was inhibited at much lower concentrations of the cokery soil (EC50-14 d=28%) than the viability of adults (EC50-14 d=74%). Only plant growth was inhibited (EC50-17d=26%) while germination was not. Chemical analyses of water extracts allowed us to identify inorganic water-extractable pollutants as responsible for toxicity on aquatic species, especially copper for effects on D. magna and C. dubia. The soil toxicity on collembolae and earthworms could be explained by 4 PAH congeners-fluorene, phenanthrene, pyrene, and fluoranthene. Yet, toxicity of the cokery soil as a whole was much lower than toxicity that could be deduced from the concentration of each congener in spiked soils, indicating that pollutants in the soil became less bioavailable with ageing. PMID:17382389

Eom, I C; Rast, C; Veber, A M; Vasseur, P

2007-06-01

291

Chemical extraction of arsenic from contaminated soil under subcritical conditions.  

PubMed

In this research, we investigated a chemical extraction process, under subcritical conditions, for arsenic (As)-contaminated soil in the vicinity of an abandoned smelting plant in South Korea. The total concentration of As in soil was 75.5 mg/kg, 68% of which was As(+III). X-ray photoelectron spectroscopy analysis showed that the possible As(+III)-bearing compounds in the soil were As(2)O(3) and R-AsOOH. At 20°C, 100 mM of NaOH could extract 26% of the As from the soil samples. In contrast, 100 mM of ethylenediaminetetraacetic acid (EDTA) and citric acid showed less than 10% extraction efficiency. However, as the temperature increased to 250 and 300°C, extraction efficiencies increased to 75-91% and 94-103%, respectively, regardless of the extraction reagent used. Control experiments with subcritical water at 300°C showed complete extraction of As from the soil. Arsenic species in the solution extracted at 300°C indicated that subcritical water oxidation may be involved in the dissolution of As(+III)-bearing minerals under given conditions. Our results suggest that subcritical water extraction/oxidation is a promising option for effective disposal of As-contaminated soil. PMID:21601910

Oh, Seok-Young; Yoon, Myong-Keun; Kim, Ick-Hyun; Kim, Ju Yup; Bae, Wookeun

2011-07-15

292

Particulate copper in soils and surface runoff from contaminated sandy soils under citrus production.  

PubMed

Soil contamination by copper (Cu) is a worldwide concern. Laboratory incubation and soil Cu characterization were conducted to examine the effects of external Cu loading and liming on Cu speciation in both bulk soil and particulates of an Alfisol and Spodosol under citrus production. Also, drainage water from the sites was evaluated for dissolved and particulate forms of Cu. Soil available Cu estimated by CaCl2, NH4OAc, or Mehlich-3 extraction significantly increased with external Cu loads and decreased with soil pH. Most increases in soil Cu occurred in the exchangeable and oxide-bound fractions. Organically bound Cu was the dominant fraction in both bulk soil and particulates, but more in particulates than bulk soil (P ? 0.001). Organically bound Cu was highly correlated with total recoverable Cu (P ? 0.01), increased significantly with external Cu loads (P ? 0.001), and decreased with soil pH (P ? 0.05). Lime addition converted part of Cu from available pools to more stable forms. Organically bound Cu complexes were found to dominate in soil solution or surface runoff. These results indicate that most Cu accumulated in the contaminated soils is highly mobile, and thus may impact citrus production and the environment. PMID:23740300

Bakshi, Santanu; He, Zhenli L; Harris, Willie G

2013-12-01

293

Remediation of contaminated soils and sediments using Daramend bioremediation  

SciTech Connect

Soils and sediments containing polyaromatic hydrocarbons (PAH), petroleum hydrocarbons, heavy oils, chlorinated phenols, pesticides, herbicides and phthalates, either individually or in combination, have been difficult to remediate in the past. Not only the species of contaminant, but contaminant concentrations were roadblocks to successful use of bioremediation. Daramend{sup Tm} remediation has removed many of these obstacles through extensive research. Bench-scale, pilot-scale and full-scale demonstrations have been conducted at a variety of industrial sites. At a manufactured gas site, 295 days of Daramend remediation reduced concentrations of chrysene and fluoranthene from 38.9 mg/kg to 5.9 mg/kg and 84.6 mg/kg to 7.8 mg/kg respectively. Elsewhere, the total PAH concentration in a silty soil was reduced from 1,442 mg/kg to 36 mg/kg. Concentrations of even the most refractory PAHs (e.g. pyrene, benzo(a)pyrene) were reduced to below the established clean-up guidelines. Total petroleum hydrocarbons (diesel fuel) have also been reduced from 8,700 mg/kg to 34 mg/kg after 182 days of treatment. Similarly, in a clay soil contaminated by crude oil processing, the concentrations of high molecular weight aliphatic hydrocarbons were rapidly reduced (138 days) to below the remediation criteria. Demonstrations with wood treatment site soils have proven Daramend remediation effective in enhancing the target compound degradation rates. Soils containing 2170 mg PCP/kg were shown to contain only 11 mg PCP/kg after 280 days of Darmend remediation. The issue of toxicity of soil containing increased amounts of pentachlorophenols was solved. Performance data collected during these projects indicate that Daramend remediation provides a cost effective method for clean-up of soils and sediments containing a variety of organic compounds.

Burwell, S.W.; Bucens, P.G.; Seech, A.G.

1996-05-01

294

The Effects of Microbial Population on Phytoremediation of Petroleum Contaminated Soils Using Tall Fescue  

Microsoft Academic Search

Petroleum contamination of soil is a serious problem throughout the south of Tehran and Khuzestan province of Iran. Vegetation may play an important role in the biodegradation of toxic organic chemicals in soil. For petroleum compounds, the presence of rhizosphere microflora may accelerate biodegradation of the contaminants. In a greenhouse study, petroleum contaminated soils from sites around Tehran Refinery Planet

JAHANGIR ABEDI-KOUPAI; REZA EZZATIAN; MANOUCHEHR VOSSOUGHI-SHAVARI; SOHEILA YAGHMAEI; MEHDI BORGHEI

295

AQUEOUS Pb REDUCTION IN Pb-CONTAMINATED SOILS BY FLORIDA PHOSPHATE ROCKS  

E-print Network

Florida phosphate rocks (PR) to immobilize aqueous Pb from Pb-contaminated soils. Occidental Chemical PR-contaminated soils include chemical, physical and biological treatments. However, most current treatment technologies). In situ stabilization of Pb-contaminated soil is a cost-effective remediation method. Remediating a lead

Ma, Lena

296

Effects of soil organic matter and ageing on remediation of diesel-contaminated soil.  

PubMed

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. PMID:23437667

Liu, Pao-Wen Grace; Wang, Sih-Yu; Huang, Shen-Gzhi; Wang, Ming-Zhi

2012-12-01

297

Remediation of soil contaminated with dioxins by subcritical water extraction.  

PubMed

The effectiveness of subcritical water extraction (SCWE) was examined for removing dioxins from contaminated soil. Most dioxins in the soil sample were reduced at 300 degrees C or more, but decreased dioxin concentrations were also observed at 150 degrees C. After 4 h of extraction, 99.4%, 94.5% and 60% of PCDDs were removed from samples at 350, 300 and 150 degrees C, respectively. It was also determined that degradation of dioxins had occurred, since the sum of dioxins in the soil plus water extracts after the experiments had considerably decreased. This study revealed that pressurizing is not essential for the removal of dioxins. Reduction was complete within 30 min at 350 degrees C; however, it took a much longer time at lower temperatures. The results of addition experiments in which OCDDs were added to different types of soil samples have shown that dechlorination is one of the major reaction pathways. After addition of OCDD to soil samples, experiments were carried out to examine in detail the degradation pathways of PCDDs. The removal rates and congener profiles varied among soil types. Although it was previously assumed that removal rates and congener profiles depended on the chemical components in soil, nonparametric statistical analysis revealed no significant relationship between the rate of reduction and elements present in the soil. It was confirmed from isomer patterns that dechlorination of the 2,3,7,8-positions in PCDDs takes place somewhat faster than for the 1,4,6,9-positions. PMID:14559261

Hashimoto, Shunji; Watanabe, Kiyohiko; Nose, Kazutoshi; Morita, Masatoshi

2004-01-01

298

Investigating the control of mercury volatilization from contaminated soil  

NASA Astrophysics Data System (ADS)

In previous investigations of growing earthworms, Lumbricus terrestris, in contaminated soil, we have found that volatilization of mercury (Hg) to be an active process. The question to be answered is what causes the reduction of Hg to a more volatile state in the soil, could it be the earthworms? A series of laboratory tests were conducted to determine the mechanism of Hg reduction. The tests revealed that earthworms bioaccumulate the Hg in their tissue, but do not aid in the reduction process. Microbial reduction of the Hg appears to be the mechanism. Two dissimilar soil types were tested; both were heated for 96 hours at 100oC. After cooling, both soil types were spiked with 100 mg of Hg per Kg of soil. Integrated Hg vapor samples were collected immediately above the soil surface over a 3 day period and analyzed by cold vapor atomic adsorption. After heat treatment both soil types had a statistically significantly higher rate of volatilization than unheated soils. We interpret this result as indicating that heating preferentially selected microbial spores that facilitated the Hg reduction.

Steffy, D. A.; Nichols, A.

2009-12-01

299

Electrokinetic treatment of contaminated soils, sludges, and lagoons. Final report  

SciTech Connect

The electrokinetic process is an emerging technology for in-situ soil decontamination, in which chemical species, both ionic and nonionic are transported to an electrode site in soil. These products are subsequently removed from the ground via collection systems engineered for each specific application. Electrokinetics refer to movement of water, ions and charged particles relative to one another under the action of an applied direct current electric field. In a porous compact matrix of surface charged particles such as soil, the ion containing pore fluid may be made to flow to collection sites under the applied field. This report describes the effort undertaken to investigate electrokinetically enhanced transport of soil contaminants in synthetic systems. These systems consisted of clay or clay-sand mixtures containing known concentration of a selected heavy metal salt solution or an organic compound. Metals, surrogate radio nuclides and organic compounds evaluated in the program were representatives of those found at a majority of DOE sites. Degree of removal of these metals from soil by the electrokinetic treatment process was assessed through the metal concentration profiles generated across the soil between the electrodes. The best removals, from about 85 to 95% were achieved at the anode side of the soil specimens. Transient pH change had an effect on the metal movement via transient creation of different metal species with different ionic mobilities, as well as changing of the surface characteristics of the soil medium.

Wittle, J.K. [Electro-Petroleum, Inc., Wayne, PA (United States); Pamukcu, S. [Lehigh Univ., Bethlehem, PA (United States). Dept. of Civil Engineering

1993-04-01

300

Movement of inorganic contaminants in soils and plants: An overview  

SciTech Connect

The movement of both essential and pollutant trace elements through agricultural food chains is a complex problem. Such elements as As, B, Cd, Cr, Cu, Hg, Ni, Pb, Se, U, Vn and Zn, are generally present naturally in soils but may be elevated because of human activities, such as fossil fuel combustion, sludge amendment to soil, fertilizer application, and agricultural practices, i.e., cultivation and irrigation. Although a significant effort has been expended over the past 40 years to evaluate and quantify the transfer of trace elements from soils to plants, more attention needs to be given to mechanisms within the soil and plant, which influence solubility, chemical speciation, mobility, uptake, transport and impact of the absorbed element in plants for trace metals to be retained in the soil matrix. Although soils do not possess unlimited capability in attenuating inorganic contaminants, soils and even certain plant species do have capacities for retaining large amounts of some trace metals. The prediction of movement of trace elements in the agricultural ecosystem must be partially based on understanding the soil processes governing chemical form and the uptake and behavior of trace elements within plants.

Banuelos, G. [USDA-ARS Water Management Research Lab., Fresno, CA (United States)

1995-12-31

301

[Phytoavailability and chemical speciation of cadmium in different Cd-contaminated soils with crop root return].  

PubMed

Pot experiments were conducted under greenhouse condition to investigate the effects of crop root return on succeeding crops growth, Cd uptake and soil Cd speciation in Cd-contaminated soil and artificial Cd-contaminated soil. The results showed that the amount of root residue returned to soil by corn and kidney bean growth successive for 3 times was 0.4%-1.1%. The Cd returned to soil by root residue was 1.3%-3.5% to the total soil Cd. There was no significant difference in the shoot dry weights of winter wheat and Chinese cabbage grown on the 2 Cd-contaminated soils with and without root return. While Cd concentration of Chinese cabbage increased significantly in the Cd-contaminated soil with corn or kidney bean root return. Light fraction of soil organic matter increased with root return in both of the Cd-contaminated soils. The percentage of Cd in the light fraction of soil organic matter increased with root return in the artificial Cd-contaminated soil. Soil carbonates-bound Cd concentration decreased significantly with corn root return in the Cd-contaminated soil. Soil exchangeable Cd concentration decreased and soil Fe-Mn oxide-bound Cd concentration increased significantly with kidney bean root return in the artificial Cd-contaminated soil. PMID:23668141

Zhang, Jing; Yu, Ling-Ling; Xin, Shu-Zhen; Su, De-Chun

2013-02-01

302

Geochemistry Of Lead In Contaminated Soils: Effects Of Soil Physico-Chemical Properties  

NASA Astrophysics Data System (ADS)

Lead (Pb) is an environmental contaminant with proven human health effects. When assessing human health risks associated with Pb, one of the most common exposure pathways typically evaluated is soil ingestion by children. However, bioaccessibility of Pb primarily depends on the solubility and hence, the geochemical form of Pb, which in turn is a function of site specific soil chemistry. Certain fractions of ingested soil-Pb may not dissociate during digestion in the gastro-intestinal tract, and hence, may not be available for transport across the intestinal membrane. Therefore, this study is being currently performed to assess the geochemical forms and bioaccessibility of Pb in soils with varying physico-chemical properties. In order to elucidate the level of Pb that can be ingested and assimilated by humans, an in-vitro model that simulates the physiological conditions of the human digestive system has been developed and is being used in this study. Four different types of soils from the Immokalee (an acid sandy soil with minimal Pb retention potential), Millhopper (a sandy loam with high Fe/Al content), Pahokee (a muck soil with more than 80% soil organic matter), and Tobosa series (an alkaline soil with high clay content) were artificially contaminated with Pb as lead nitrate at the rate equivalent to 0, 400, 800, and 1200 mg/kg dry soil. Analysis of soils by a sequential extraction method at time zero (immediately after spiking) showed that Immokalee and Millhopper soils had the highest amount of Pb in exchangeable form, whereas Pahokee and Tobosa soils had higher percentages of carbonate-bound and Fe/Al-bound Pb. The results of in-vitro experiment at time zero showed that majority of Pb was dissolved in the acidic stomach environment in Immokalee, Millhopper, and Tobosa, whereas it was in the intestinal phase in Pahokee soils. Because the soil system is not in equilibrium at time zero, the effect of soil properties on Pb geochemistry is not clear as yet. The subsequent analysis of soils (after 6 and 8 months months) is expected to better demonstrate the influence of soil properties on human bioaccessibility of Pb in contaminated soils. Furthermore, the geochemical forms of Pb will be correlated with bioaccessible Pb to identify those soil-Pb species with higher solubility in the human gastrointestinal system. Key words: Lead, Geochemical species, Bioaccessibility, In-vitro model, Health risk

Saminathan, S.; Sarkar, D.; Datta, R.; Andra, S. P.

2006-05-01

303

Organochlorinated pesticide degrading microorganisms isolated from contaminated soil.  

PubMed

Degradation of selected organochlorinated pesticides (?-hexachlorocyclohexane - ?-HCH, dichlorodiphenyltrichloroethane - DDT, hexachlorobenzene - HCB) by soil microorganisms was studied. Bacterial strains isolated from contaminated soil from Klatovy-Luby, Hajek and Neratovice, Czech Republic, capable of growth on the selected pesticides were isolated and characterised. These isolates were subjected to characterisation and identification by MS MALDI-TOF of whole cells and sequence analysis of 16S rRNA genes. The isolates were screened by gas chromatography for their ability to degrade the selected pesticides. Some isolates were able to degrade pesticides, and the formation of degradation products (?-pentachlorocyclohexane (?-PCCH), dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD)) observed in liquid culture confirmed their degradation capability. The isolates and DNA samples isolated from the contaminated soil were also screened for the bphA1 gene (encoding biphenyl-2,3-dioxygenase, the first enzyme in the PCB degradation pathway) and its occurrence was demonstrated. The isolates were also screened for the presence of linA, encoding dehydrochlorinase, the first enzyme of the HCH degradation pathway. The linA gene could not be found in any of the tested isolates, possibly due to the high specificity of the primers used. The isolates with the most effective degradation abilities could be used for further in situ bioremediation experiments with contaminated soil. PMID:25094051

Lovecka, Petra; Pacovska, Iva; Stursa, Petr; Vrchotova, Blanka; Kochankova, Lucie; Demnerova, Katerina

2015-01-25

304

Migration of Contaminated Soil and Airborne Particulates to Indoor Dust  

PubMed Central

We have developed a modeling and measurement framework for assessing transport of contaminated soils and airborne particulates into a residence, their subsequent distribution indoors via resuspension and deposition processes, and removal by cleaning and building exhalation of suspended particles. The model explicitly accounts for the formation of house dust as a mixture of organic matter (OM) such as shed skin cells and organic fibers, soil tracked-in on footwear, and particulate matter (PM) derived from the infiltration of outdoor air. We derived formulas for use with measurements of inorganic contaminants, crustal tracers, OM, and PM to quantify selected transport parameters. Application of the model to residences in the U.S. Midwest indicates that As in ambient air can account for nearly 60% of the As input to floor dust, with soil track-in representing the remainder. Historic data on Pb contamination in Sacramento, CA, was used to reconstruct sources of Pb in indoor dust, showing that airborne Pb was likely the dominant source in the early 1980s. However, as airborne Pb levels declined due to the phase out of leaded gasoline, soil resuspension and track-in eventually became the primary sources of Pb in house dust. PMID:19924944

Layton, David W.; Beamer, Paloma I.

2009-01-01

305

[Influence of the consumption of radioactive contaminated food on the formation of the irradiation levels and health of the inhabitants of radioactive contaminated regions of Ukraine].  

PubMed

Within all these years after the Chernobyl disaster the population of contaminated areas of the Rivne region was shown to consume radioactive contaminated foodstuffs. The main components of the formation of the internal irradiation of the population in them were and remain locally sourced milk and meat, forest mushrooms and berries. After 1991, the largest annual internal doses in persons observed in 1997 varied from 2,2 to 1,45 mSv/year and in 2011--in the inhabitants of the village of El'no they were yet reaching 1.43 mSv/year. After 2003, exposure levels in most inhabitatants of affected areas exceeded the criterion specified by national legislation for residents of the tightened radioecological control zone (0,5 mSv/year). The long-term residence in the contaminated area, elevated levels of chronic internal exposure, lack of radioactively sound foodstuffs and involuntary consumption in 1987-2011 radioactively contaminated food of local production were noted to led to an increase in general morbidity, and incidence of endocrine diseases rate and their separate nosological forms. PMID:24749279

Khomenko, I M; Omel'yanets, N I

2014-01-01

306

Comparing statistical tests for detecting soil contamination greater than background  

SciTech Connect

The Washington State Department of Ecology (WSDE) recently issued a report that provides guidance on statistical issues regarding investigation and cleanup of soil and groundwater contamination under the Model Toxics Control Act Cleanup Regulation. Included in the report are procedures for determining a background-based cleanup standard and for conducting a 3-step statistical test procedure to decide if a site is contaminated greater than the background standard. The guidance specifies that the State test should only be used if the background and site data are lognormally distributed. The guidance in WSDE allows for using alternative tests on a site-specific basis if prior approval is obtained from WSDE. This report presents the results of a Monte Carlo computer simulation study conducted to evaluate the performance of the State test and several alternative tests for various contamination scenarios (background and site data distributions). The primary test performance criteria are (1) the probability the test will indicate that a contaminated site is indeed contaminated, and (2) the probability that the test will indicate an uncontaminated site is contaminated. The simulation study was conducted assuming the background concentrations were from lognormal or Weibull distributions. The site data were drawn from distributions selected to represent various contamination scenarios. The statistical tests studied are the State test, t test, Satterthwaite`s t test, five distribution-free tests, and several tandem tests (wherein two or more tests are conducted using the same data set).

Hardin, J.W.; Gilbert, R.O.

1993-12-01

307

A humic acid extract from lignite for reclaiming contaminated soils  

SciTech Connect

A unique form of a humic compound was developed by A.I. Shulgin, A.A. Shapovalov and U.G. Putsykin of Moscow, Russia using a patented process from lignite coal. This material appears to have properties that complexes certain heavy metals such as Pb, Cu, Cd, etc. as well as PCB's. This study was restricted to its interaction with Pb. Both greenhouse and laboratory studies were conducted from a quantity of humic acid (Stabilite) from the SET company in Louisville, KY. Although Stabilite contains some Pb, in the laboratory study, significant reductions in Pb concentration occurred. Stabilite also reduced Pb levels of an artificially contaminated soil having 1,000 ppm Pb for both the residual soil as well as water leached through this soil. Corn grown in this did not extract Pb from the Stabilite treated soil.

Barnhisel, R.I.

1999-07-01

308

Characterization of mercury forms in contaminated floodplain soils  

SciTech Connect

The chemical form or speciation of Hg in the floodplain soils of the East Fork Poplar Creek in Oak Ridge TN, a site contaminated from past industrial activity, was investigated. Hg speciation in the soils is an important factor in controlling the fate and effect of mercury at the site and in assessing human health and ecological risk. Application of 3 different sequential extraction speciation schemes indicated the Hg at the site was predominantly relatively insoluble mercuric sulfide or metallic Hg, though the relative proportions of each did not agree well between procedures. Application of x-ray and electron beam studies to site soils confirmed the presence of metacinnabar, a form of mercuric sulfide, the first known evidence of authigenic mercuric sulfide formation in soils.

Barnett, M.O.; Turner, R.R.; Henson, T.J. [Oak Ridge National Lab., TN (United States); Harris, L.A.; Melton, R.E.; Stevenson, R.J. [Oak Ridge K-25 Site, TN (United States)

1994-12-31

309

Uranium-contaminated soils: Ultramicrotomy and electron beam analysis  

SciTech Connect

Uranium-contaminated soils from the U.S. Department of Energy (DOE) Fernald Site, Ohio, have been examined by a combination of scanning electron microscopy with backscattered electron imaging (SEM/BSE) and analytical electron microscopy (AEM). The inhomogeneous distribution of particulate uranium phases in the soil required the development of a method for using ultramicrotomy to prepare transmission electron microscopy (TEM) thin sections of the SEM mounts. A water-miscible resin was selected that allowed comparison between SEM and TEM images, permitting representative sampling of the soil. Uranium was found in iron oxides, silicates (soddyite), phosphates (autunites), and fluorite (UO{sub 2}). No uranium was detected in association with phyllosilicates in the soil.

Buck, E.C.; Dietz, N.L.; Bates, J.K.; Cunnane, J.C.

1994-02-01

310

Kinetics of zinc and cadmium release in freshly contaminated soils.  

PubMed

The kinetics of metal release from the solid phase to solution was measured on two sets of 14 freshly contaminated soils with diverse properties. From measurements of metal concentrations in extracted soil pore water, the amount accumulated from the soil by diffusive gradients in thin-film (DGT) devices, and the distribution coefficient for labile metal, Kdl, estimated by isotopic exchange, we calculated the response time, Tc, of the soil-solution system to the removal of metal by DGT and the rate constant for release from the solid phase, k(-1). Resupply was so fast for Zn that Tc (and k(-1)) could be measured only in three of the soils, with either a silty or a sandy loam texture and low to intermediate pH (4.84-5.66). In only six clay soils was resupply of Cd too fast to measure. The generally slower release rates of Cd compared to Zn may reflect the 100-fold lower concentration of Cd, which allowed a greater proportion of it to occupy stronger binding sites with slower release rates. The rate constants derived indicate that supply from the solid phase to solution will not limit uptake of Cd or Zn by plants in clay soils, but it could be a factor in sandy or silty soils with a low pH. These findings suggest that risk assessment of clay soils could be undertaken using measurements of metals in soil solution. However, devices such as DGT, which respond to the kinetics of supply, are necessary to assess available metal in low pH, sandy, and silty soils. PMID:16566150

Zhang, Hao; Davison, William; Tye, Andy M; Crout, Neil M J; Young, Scott D

2006-03-01

311

Effect Of Soil Properties On The Geochemical Speciation Of Arsenic In Contaminated Soils: A Greenhouse Study  

NASA Astrophysics Data System (ADS)

Land-applied arsenical pesticides have contributed elevated soil arsenic (As) levels. Many baseline risk assessments As-contaminated sites assume that all As present in the soil is bioavailable, thereby potentially overestimating the actual health risk. However, risk from As exposure is associated only with those forms of As that are potentially extractable by the human gastrointestinal juices. It has been demonstrated that As may exist in several geochemical forms depending on soil chemical properties, which may or may not be bioavailable. The current study aims at addressing the issue of soil variability on As bioavailability as a function of soil physico-chemical properties in a greenhouse setting involving dynamic interactions between soil, water and plants. Four different soils were chosen based on their potential differences with respect to As reactivity: Immokalee, an acid sand with low extractable Fe/Al, having minimal arsenic retention capacity; Millhopper, an acid sandy loam with high extractable Fe/Al oxides; Pahokee Muck soil with 85% soil organic matter (SOM) as well as high Fe/Al content; and Orelia soil with high clay and Fe/Al content. Soils were amended with sodium arsenate (675 and 1500 mg/Kg). Rice (Oryza sativa) was used as the test crop. A sequential extraction scheme was employed to identify the geochemical forms of As in soils (soluble, exchangeable, organic, Fe/Al-bound, Ca/Mg-bound, residual) immediately after spiking; after 3 mo; and after 6 mo of equilibration time. Concentrations of these As forms were correlated with the in-vitro bioavailable As fractions to identify those As fractions that are most likely to be bioavailable. Results from this study showed that there was little to no plant growth in the contaminated soils. Sequential extractions of the soil indicated that arsenic is strongly adsorbed onto soil amorphous iron/aluminum oxides, and the degree of arsenic retention is a direct function of equilibration time.

Sharma, S.; Sarkar, D.; Datta, R.

2005-05-01

312

Sources of arsenic and fluoride in highly contaminated soils causing groundwater contamination in Punjab, Pakistan.  

PubMed

Highly contaminated groundwater, with arsenic (As) and fluoride (F(-)) concentrations of up to 2.4 and 22.8 mg/L, respectively, has been traced to anthropogenic inputs to the soil. In the present study, samples collected from the soil surface and sediments from the most heavily polluted area of Punjab were analyzed to determine the F(-) and As distribution in the soil. The surface soils mainly comprise permeable aeolian sediment on a Pleistocene terrace and layers of sand and silt on an alluvial flood plain. Although the alluvial sediments contain low levels of F, the terrace soils contain high concentrations of soluble F(-) (maximum, 16 mg/kg; mean, 4 mg/kg; pH > 8.0). Three anthropogenic sources were identified as fertilizers, combusted coal, and industrial waste, with phosphate fertilizer being the most significance source of F(-) accumulated in the soil. The mean concentration of As in the surface soil samples was 10.2 mg/kg, with the highest concentration being 35 mg/kg. The presence of high levels of As in the surface soil implies the contribution of air pollutants derived from coal combustion and the use of fertilizers. Intensive mineral weathering under oxidizing conditions produces highly alkaline water that dissolves the F(-) and As adsorbed on the soil, thus releasing it into the local groundwater. PMID:18937006

Farooqi, Abida; Masuda, Harue; Siddiqui, Rehan; Naseem, Muhammad

2009-05-01

313

Sources of arsenic and fluoride in highly contaminated soils causing groundwater contamination in Punjab, Pakistan  

SciTech Connect

Highly contaminated groundwater, with arsenic (As) and fluoride (F{sup -}) concentrations of up to 2.4 and 22.8 mg/L, respectively, has been traced to anthropogenic inputs to the soil. In the present study, samples collected from the soil surface and sediments from the most heavily polluted area of Punjab were analyzed to determine the F{sup -} and As distribution in the soil. The surface soils mainly comprise permeable aeolian sediment on a Pleistocene terrace and layers of sand and silt on an alluvial flood plain. Although the alluvial sediments contain low levels of F, the terrace soils contain high concentrations of soluble F{sup -} (maximum, 16 mg/kg; mean, 4 mg/kg; pH > 8.0). Three anthropogenic sources were identified as fertilizers, combusted coal, and industrial waste, with phosphate fertilizer being the most significance source of F{sup -} accumulated in the soil. The mean concentration of As in the surface soil samples was 10.2 mg/kg, with the highest concentration being 35 mg/kg. The presence of high levels of As in the surface soil implies the contribution of air pollutants derived from coal combustion and the use of fertilizers. Intensive mineral weathering under oxidizing conditions produces highly alkaline water that dissolves the F{sup -} and As adsorbed on the soil, thus releasing it into the local groundwater.

Farooqi, A.; Masuda, H.; Siddiqui, R.; Naseem, M. [Fatima Jinnah Women University, Rawalpindi (Pakistan). Dept. of Environmental Science

2009-05-15

314

Radioactive contamination of plants in Japan covered with rain-out from H-bomb detonations in March-May 1954 at Bikini Atoll, Marshall Isls. (Part 2) Radioactive elements of contaminated plants  

Microsoft Academic Search

IntroductionIn the preceding paper, the author pointed out the necessity of investigating the contaminating radioactive elements in agricultural crops. In this paper. a simple radiochemical treatise on the contaminated plants is discussed.

Michihiko Yatazawa

1955-01-01

315

Electrokinetic electrode system for extraction of soil contaminants from unsaturated soils  

DOEpatents

There is presented an electrokinetic electrode assembly for use in extraction of soil contaminants from unsaturated soil in situ. The assembly includes a housing for retaining a liquid comprising an electrolyte solution, pure water, and soil water, the housing being in part of porous material capable of holding a vacuum. An electrode is mounted in the housing. The housing is provided with a vacuum orifice for effecting a vacuum within the housing selectively to control flow of soil water through the housing into the chamber and to control outflow of the liquid from the chamber. The assembly further includes conduit means for removing the liquid from the housing and returning the electrolyte solution to the housing, and a conduit for admitting pure water to the housing. There is further presented an electrode system and method for extraction of soil contaminants, the system and method utilizing at least two electrode assemblies as described above.

Lindgren, Eric R. (Albuquerque, NM); Mattson, Earl D. (Albuquerque, NM)

1995-01-01

316

Electrokinetic electrode system for extraction of soil contaminants from unsaturated soils  

DOEpatents

An electrokinetic electrode assembly is described for use in extraction of soil contaminants from unsaturated soil in situ. The assembly includes a housing for retaining a liquid comprising an electrolyte solution, pure water, and soil water, the housing being in part of porous material capable of holding a vacuum. An electrode is mounted in the housing. The housing is provided with a vacuum orifice for effecting a vacuum within the housing selectively to control flow of soil water through the housing into the chamber and to control outflow of the liquid from the chamber. The assembly further includes conduit means for removing the liquid from the housing and returning the electrolyte solution to the housing, and a conduit for admitting pure water to the housing. An electrode system and method are also revealed for extraction of soil contaminants. The system and method utilize at least two electrode assemblies as described above. 5 figs.

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

1995-07-25

317

Influence of organic and inorganic soil amendments on plant growth in crude oil-contaminated soil.  

PubMed

Phytoremediation can be a viable alternative to traditional, more costly remediation techniques. Three greenhouse studies were conducted to evaluate plant growth with different soil amendments in crude oil-contaminated soil. Growth of alfalfa (Medicago sativa L., cultivar: Riley), bermudagrass (Cynodon dactylon L., cultivar: Common), crabgrass (Digitaria sanguinalis, cultivar: Large), fescue (Lolium arundinaceum Schreb., cultivar: Kentucky 31), and ryegrass (Lolium multiflorum Lam., cultivar: Marshall) was determined in crude oil-contaminated soil amended with either inorganic fertilizer, hardwood sawdust, papermill sludge, broiler litter or unamended (control). In the first study, the addition of broiler litter reduced seed germination for ryegrass, fescue, and alfalfa. In the second study, bermudagrass grown in broiler litter-amended soil produced the most shoot biomass, bermudagrass produced the most root biomass, and crabgrass and bermudagrass produced the most root length. In the third study, soil amended with broiler litter resulted in the greatest reduction in gravimetric total petroleum hydrocarbon (TPH) levels across the six plant treatments following the 14-wk study. Ryegrass produced more root biomass than any other species when grown in inorganic fertilizer- or hardwood sawdust + inorganic fertilizer-amended soil. The studies demonstrated that soil amendments and plant species selection were important considerations for phytoremediation of crude oil-contaminated soil. PMID:14750564

White, P M; Wolf, D C; Thoma, G J; Reynolds, C M

2003-01-01

318

Assessing the Educational Needs of Urban Gardeners and Farmers on the Subject of Soil Contamination  

ERIC Educational Resources Information Center

Participation in urban agriculture is growing throughout the United States; however, potential soil contaminants in urban environments present challenges. Individuals in direct contact with urban soil should be aware of urban soil quality and soil contamination issues to minimize environmental and human health risks. The study reported here…

Harms, Ashley Marie Raes; Presley, DeAnn Ricks; Hettiarachchi, Ganga M.; Thien, Stephen J.

2013-01-01

319

Characterization and remediation of soils contaminated with uranium.  

PubMed

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. PMID:18771850

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

2009-04-30

320

Evaluation of solidification/stabilization for treating explosives contaminated soils  

SciTech Connect

The success of solidification/stabilization (S/S) for treating explosives contaminated soils was evaluated using a variety of physical, chemical, and contaminant release testing methods. The analytes of concern included explosives and their degradation products (TNT, RDX, HMX, 2, 4-Dinitrotoluene, 2,6-dinitrotoluene, 2,4,6-Trinitrotoluene, 2-Amino-4,6-Dinitrotoluene, 4-Amino-2,6-Dinitrobenzene, 2,4-Dinitrotoluene) and PAH`s (Benzo(a)anthracene, Benzo(b)fluoranthene, Benzo(k)fluoranthene, Benzo(a)pyrene, Chrysene, Dibenz(a,h) anthracene, and Ideno (1,2,3-cd)pyrene). All Toxicity Characteristic Leaching Procedure (TCLP) leachate analytes, except 2-Am-4,6-TNT was reduced approximately 97%. The release of 2,4-DNT was also significantly reduced. The results of the Sequential Batch Leach Test (SBLT) were mixed. The PAH compounds were not identified above detectable limits in the leachates from either the untreated soil or the treated soils. Release of 2,4,6-TNT was reduced to undetectable. However, other explosives related compounds (2-Am-4, 6-DNT) were identified in the leachates from the treated soils that were not identified in the untreated soil. Organic transformations in the highly alkaline environment associated with S/S or sample heterogeneity are suspected to cause this phenomena.

Cullinane, M.J. Jr.; Channell, M. [Army Engineer Waterways Experiment Station, Vicksburg, MS (United States)

1996-12-31

321

Phytoremediation of soils contaminated with toxic elements and radionuclides  

SciTech Connect

At many US Department of Energy (US DOE) facilities and other sites, surface soils over relatively large areas are contaminated with heavy metals, radionuclides, and other toxic elements, often at only a relatively small factor above regulatory action levels. Cleanup of such sites presents major challenges, because currently available soil remediation technologies can be very expensive. In response, the US DOE`s Office of Technology Development, through the Western Environmental Technology Office, is sponsoring research in the area of phytoremediation. Phytoremediation is an emerging technology that uses higher plants to transfer toxic elements and radionuclides from surface soils into aboveground biomass. Some plants, termed hyperaccumulators, take up toxic elements in substantial amounts, resulting in concentrations in aboveground biomass over 100 times those observed with conventional plants. After growth, the plant biomass is harvested, and the toxic elements are concentrated and reclaimed or disposed of. As growing, harvesting, and processing plant biomass is relatively inexpensive, phytoremediation can be a low-cost technology for remediation of extensive areas having lightly to moderately contaminated soils. This paper reviews the potential of hyper- and moderate accumulator plants in soil remediation, provides some comparative cost estimates, and outlines ongoing work initiated by the US DOE.

Cornish, J.E.; Goldberg, W.C. [MSE, Inc., Butte, MT (United States); Levine, R.S. [Dept. of Energy, Germantown, MD (United States). Office of Technology Development; Benemann, J.R.

1995-12-31

322

Do Chernobyl-like contaminations with (137)Cs and (90)Sr affect the microbial community, the fungal biomass and the composition of soil organic matter in soil?  

PubMed

(137)Cs and (90)Sr are the main radionuclides responsible for contamination of agricultural soils due to core melts in nuclear power plants such as Chernobyl or Fukushima. The present study focused on effects of Chernobyl-like contaminations on the bacterial and fungal community structure, the fungal biomass and the formation of soil organic matter in native and in sterilized and reinoculated soils. 2% wheat straw [m/m] was applied to a typical agricultural soil, artificially contaminated with (137)Cs and (90)Sr, and it was then incubated in microcosms for three months at 20 °C and 50% of the water-holding capacity. The development of the microbial communities was monitored with 16S and 18S rDNA denaturing gradient gel electrophoresis (DGGE). The quantification of the ergosterol content was used as a proxy for changes in the fungal biomass. Changes in the soil organic matter were determined using the (13)C cross polarization/magic angle spinning nuclear magnet resonance technique ((13)C-CP/MAS NMR). Slight but significant population shifts in the DGGE gel patterns could be related to the applied radionuclides. However, radiation-induced impacts could not be seen in either the chemical composition of the soil organic matter or in the development of the fungal biomass. Impacts caused by sterilization and reinoculation prevailed in the microcosms of the present study. Contaminations with (137)Cs or (90)Sr up to 50-fold that of the hotspots occurring in Chernobyl led to minor changes in soil microbial functions suggesting a strong resilience of natural soils with respect to radioactive contamination. PMID:23231995

Niedrée, Bastian; Berns, Anne E; Vereecken, Harry; Burauel, Peter

2013-04-01

323

Functioning of metal contaminated garden soil after remediation.  

PubMed

The effect of remediation using three EDTA doses (10, 30, 60 mmol kg(-1)) on soil functioning was assessed using column experiment and Brassica rapa. Soil washing removed up to 77, 29 and 72% of metals from soil contaminated with 1378, 578 and 8.5 mg kg(-1) of Pb, Zn and Cd, respectively. Sequential extraction indicated removal from the carbonate soil fraction. Metal oral-accessibility from the stomach phase was reduced by up to 75 and from the small intestine by up to 79% (Pb). Part of metals (up to 0.8% Cd) was lost due to leaching from columns. Remediation reduced toxic metal soil-root transfer by up to 61% but did not prevent metal accumulation in leaves. The fitness of plants grown on EDTA washed soils (gas exchange, fluorescence) was not compromised. Remediation initially reduced the soil DNA content (up to 29%, 30 mmol kg(-1) EDTA) and changed the structure of microbial population. PMID:23246748

Jelusic, Masa; Grcman, Helena; Vodnik, Dominik; Suhadolc, Metka; Lestan, Domen

2013-03-01

324

Relationship between the {sup 137}Cs whole-body counting results and soil and food contamination in farms near Chernobyl  

SciTech Connect

The authors measured the radioactivity in the soil and child food samples from farms near Mogilev (56--270 GBq km{sup {minus}2} {sup 137}Cs), Gomel (36--810 GBq km{sup {minus}2} {sup 137}Cs), and Klincy (59--270 GBq km{sup {minus}2} {sup 137}Cs), who had whole-body {sup 137}Cs counting results measured as part of a health examination in the Chernobyl Sasakawa Health and Medical Cooperation Project. Soil contamination on the family farm seems to be the main source of human contamination because most of the people in the area live on small farms and they and their domestic animals eat crops from the farms. A clear correlation was found between the children's whole-body {sup 137}Cs counting results and the radioactivity in their food (correlation coefficient: 0.76; confidence level of correlation: 3.2 x 10{sup {minus}9}). There were also significant correlations between the whole-body {sup 137}Cs counting results and both the radioactivity of the soil samples (correlation coefficient: 0.22; confidence level of correlation: 0.0107) and the average contamination level of their current residence (correlation coefficient: 0.20; confidence level of correlation: 0.0174).

Takatsuji, Toshihiro; Sato, Hitoshi; Takada, Jun [and others] [and others

2000-01-01

325

COPING WITH CONTAMINATED SEDIMENTS AND SOILS IN THE URBAN ENVIRONMENT.  

SciTech Connect

Soils and sediments contaminated with toxic organic and inorganic compounds harmful to the environment and to human health are common in the urban environment. We report here on aspects of a program being carried out in the New York/New Jersey Port region to develop methods for processing dredged material from the Port to make products that are safe for introduction to commercial markets. We discuss some of the results of the program in Computational Environmental Science, Laboratory Environmental Science, and Applied Environmental Science and indicate some possible directions for future work. Overall, the program elements integrate the scientific and engineering aspects with regulatory, commercial, urban planning, local governments, and community group interests. Well-developed connections between these components are critical to the ultimate success of efforts to cope with the problems caused by contaminated urban soils and sediments.

JONES,K.W.; VAN DER LELIE,D.; MCGUIGAN,M.; ET AL.

2004-05-25

326

EFFECTIVE DOSIMETRIC HALF LIFE OF CESIUM 137 SOIL CONTAMINATION  

SciTech Connect

In the early 1960s, an area of privately-owned swamp adjacent to the US Department of Energy's Savannah River Site (SRS), known as Creek Plantation, was contaminated by site operations. Studies conducted in 1974 estimated that approximately 925 GBq of {sup 137}Cs was deposited in the swamp. Subsequently, a series of surveys--composed of 52 monitoring locations--was initiated to characterize and trend the contaminated environment. The annual, potential, maximum doses to a hypothetical hunter were estimated by conservatively using the maximum {sup 137}Cs concentrations measured in the soil. The purpose of this report is to calculate an 'effective dosimetric' half-life for {sup 137}Cs in soil (based on the maximum concentrations) and compare it to the effective environmental half-life (based on the geometric mean concentrations).

Jannik, T; P Fledderman, P; Michael Paller, M

2008-01-09

327

Bioremediation of oil-contaminated soil -- A rate model  

SciTech Connect

Three rate equations, a modified Monod equation and two mass transfer rate equations, were used to calculate the biodegradation rate, oxygen transfer rate and oil transfer rate during a bioremediation process of oil-contaminated soil. Based on experimental rate constants, these three rates were calculated and compared. It was found the bioremediation rate of oil-contaminated soil could be controlled by the mass transfer process of oil into aqueous solution (0.12 mg BOD/(1-h)). When the oil transfer rate is enhanced by at least 10 times, the oxygen transfer process (0.1--1.0 mg BOD/(1-h)) becomes the rate-controlling step. For most of the cases, the biodegradation of oil in aqueous solution is not the limiting step unless the microbial population in the aqueous solution is less than 100 mg VSS/1.

Li, K.Y.; Zhang, Y.; Xu, T. [Lamar Univ., Beaumont, TX (United States). Chemical Engineering Dept.] [Lamar Univ., Beaumont, TX (United States). Chemical Engineering Dept.

1995-12-31

328

Large-scale experience with biological treatment of contaminated soil  

SciTech Connect

The efficiency of biological methods for the cleanup of soil contaminated with total petroleum hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAH) was demonstrated by a large-scale example in which 38,000 tons of TPH- and PAH-polluted soil was treated onsite with the TERRAFERM{reg_sign} degradation system to reach the target values of 300 mg/kg TPH and 5 mg/kg PAH. Detection of the ecotoxicological potential (Microtox{reg_sign} assay) showed a significant decrease during the remediation. Low concentrations of PAH in the ground were treated by an in situ technology. The in situ treatment was combined with mechanical measures (slurry wall) to prevent the contamination from dispersing from the site.

Schulz-Berendt, V.; Poetzsch, E. [Umweltschutz Nord GmbH and Co., Ganderkesee (Germany)

1995-12-31

329

Mercury Mobilization in a Contaminated Industrial Soil for Phytoremediation  

Microsoft Academic Search

The aim of this work was to investigate the possibility of using plants for mercury (Hg) removal from a contaminated industrial soil, increasing the metal's bioaccessibility by using mobilizing agents: ammonium thiosulphate [(NH4)2S2O3] and potassium iodide (KI). The selected plant species were Brassica juncea and Poa annua. The addition of the mobilizing agents promoted Hg uptake by plants, with respect

Francesca Pedron; Gianniantonio Petruzzelli; Meri Barbafieri; Eliana Tassi; Paolo Ambrosini; Leonardo Patata

2011-01-01

330

The potential of Thlaspi caerulescens for phytoremediation of contaminated soils  

Microsoft Academic Search

Uptake of Cd, Zn, Pb and Mn by the hyperaccumulator Thlaspi caerulescens was studied by pot trials in plant growth units and in populations of wild plants growing over Pb\\/Zn base-metal mine wastes at Les Malines in the south of France. The pot trials utilised metal-contaminated soils from Auby in the Lille area. Zinc and Cd concentrations in wild plants

Brett H. Robinson; Marc Leblanc; Daniel Petit; Robert R. Brooks; John H. Kirkman; Paul E. H. Gregg

1998-01-01

331

Effect of moisture on air stripping of non volatile organic contaminants from soil  

E-print Network

(NPL) and are eligible for' funds from the Superfund Act (EPA, 1987). Current methods of contaminated soil treatment include excavanon of the soil f ll dby1 du)lb 'd ' ' u, g?, lb ' I p), . b I b expensive, especially if the soil contamination... (NPL) and are eligible for' funds from the Superfund Act (EPA, 1987). Current methods of contaminated soil treatment include excavanon of the soil f ll dby1 du)lb 'd ' ' u, g?, lb ' I p), . b I b expensive, especially if the soil contamination...

Alvarez, Roberto

2012-06-07

332

Rehabilitation of the radioactively contaminated objects and territory of the Russian Science Center Kurchatov Institute  

Microsoft Academic Search

This article is devoted to work done in 2002–2006 as part of the unified project Reabilitatsiya to rehabilitate radiation\\u000a hazardous objects and sections of the radioactively contaminated territory of the Russian Science Center Kurchatov Institute.\\u000a The main objects of the rehabilitation work were old storage sites built for radioactive wastes on the territory of the Institute\\u000a when military and civilian

E. P. Velikhov; N. N. Ponomarev-Stepnoi; V. G. Volkov; G. G. Gorodetskii; Yu. A. Zverkov; O. P. Ivanov; S. M. Koltyshev; V. D. Muzrukova; S. G. Semenov; V. E. Stepanov; A. V. Chesnokov; A. D. Shisha

2007-01-01

333

Responses of bioaugmented ryegrass to PAH soil contamination.  

PubMed

The physiological and biochemical responses of ryegrass (Lolium multiflorum) to PAH induced stress in soils contaminated with phenanthrene and pyene were investigated, in the presence of PAH-degrading bacteria (Acinetobacteria junii) or arbuscular mycorrhizal fungi (AM fungi, Glomus mossae). The parameters monitored included chlorophyll content, chlorophyll a/b ratio, soluble-carbohydrate content, soluble-protein, malondialdehyde and electrolyte leakage, and superoxide dismutase (SOD) and peroxidase (POD) activities. Ryegrass showed good resistance and acclimation to PAH stress in soil, however, PAH contamination resulted in adverse effects such as damage of photosynthetic function and acceleration of shoot senescence. At PAH level of 100 mg kg(-1), chlorophyll contents were 14% lower than control (no PAH). Activities of SOD and POD were more sensitive indicators of PAH stress as compared to other parameters. However, all parameters showed trends based on either the bioaugmentation of the plants or PAH treatment level. It was concluded that the inoculation of AMF and PAH-degrading bacteria, especially the former, have a positive effect on alleviation of PAH toxicity to ryegrass plants. Furthermore, the inoculation of AMF increased the shoot and biomass of ryegrass by 11-19% and 18-78%, respectively. Bioaugmented ryegrass plants show promise as a host plants in the phytoremediation of PAH contaminated soils. PMID:21598775

Li, J H; Yu, X Z; Wu, S C; Wang, X R; Wang, S H; Tam, N F Y; Wong, M H

2011-01-01

334

Uptake of cesium-137 by crops from contaminated soils  

SciTech Connect

The Turkish tea crop was contaminated following the Chernobyl nuclear accident. Finding ways to dispose of the contaminated tea (Camellia sinensis L.) without damaging the environment was the goal of this research conducted at the Turkish Atomic Energy Authority (TAEA). In this study, an investigation was made of {sup 137}Cs activities of the plants and the ratios of transfer of {sup 137}Cs activity to plants when the contaminated tea was applied to the soil. Experiments were conducted in the field and in pots under greenhouse conditions. The activities of the tea applied in the field ranged from 12 500 to 72 800 Bq/m{sup 2}, whereas this activity was constant at 8000 Bq/pot in the greenhouse experiment. The transfer of {sup 137}Cs from soil to the plants was between 0.037 and 1.057% for wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), corn (Zea mays indentata Sturt), bean (Phaseolus vulgaris L.), lettuce (Lactuca sativa L.), and grass (Lolium perenne L.). The ratio of the transfer of {sup 137}Cs activity to plants increased as the activity {sup 137}Cs in tea applied to soil was increased. The activity in the plants increased due to increased uptake of {sup 137}Cs by plants. 12 refs., 2 figs., 2 tabs.

Demirel, H.; Oezer, I.; Celenk, I.; Halitligil, M.B.; Oezmen, A. [Ankara Nuclear Research and Training Center (Turkey)

1994-11-01

335

In-Situ Contained And Of Volatile Soil Contaminants  

DOEpatents

The invention relates to a novel approach to containing and removing toxic waste from a subsurface environment. More specifically the present invention relates to a system for containing and removing volatile toxic chemicals from a subsurface environment using differences in surface and subsurface pressures. The present embodiment generally comprises a deep well, a horizontal tube, at least one injection well, at least one extraction well and a means for containing the waste within the waste zone (in-situ barrier). During operation the deep well air at the bottom of well (which is at a high pressure relative to the land surface as well as relative to the air in the contaminated soil) flows upward through the deep well (or deep well tube). This stream of deep well air is directed into the horizontal tube, down through the injection tube(s) (injection well(s)) and into the contaminate plume where it enhances volatization and/or removal of the contaminants.

Varvel, Mark Darrell (Idaho Falls, ID)

2005-12-27

336

In-Situ Containment and Extraction of Volatile Soil Contaminants  

DOEpatents

The invention relates to a novel approach to containing and removing toxic waste from a subsurface environment. More specifically the present invention relates to a system for containing and removing volatile toxic chemicals from a subsurface environment using differences in surface and subsurface pressures. The present embodiment generally comprises a deep well, a horizontal tube, at least one injection well, at least one extraction well and a means for containing the waste within the waste zone (in-situ barrier). During operation the deep well air at the bottom of well (which is at a high pressure relative to the land surface as well as relative to the air in the contaminated soil) flows upward through the deep well (or deep well tube). This stream of deep well air is directed into the horizontal tube, down through the injection tube(s) (injection well(s)) and into the contaminate plume where it enhances volatization and/or removal of the contaminants.

Varvel, Mark Darrell

2005-12-27

337

Radioactive contamination of rivers as a result of the accident at the Chernobyl Nuclear Power Plant  

SciTech Connect

The formation of radioactive contamination of the Belarussian rivers after the accident at the Chernobyl Nuclear Power Plant is discussed in this manuscript. On the basis of data monitored, the authors analyzed the runoff and transport of cesium-137 and strontium-90 in the Dnieper-Sozh river system. They present the details of the Iput` river monitoring. They have drawn certain conclusions concerning the transport and fate of radionuclides based upon their analysis of the data on the transport of radioactive contamination in these rivers.

Zhukova, O.M.; Matveenko, I.I. [Center of Radiation Control and Monitoring of the Belarus State Committee of Hydrometeorology, Minsk (Belarus); Myshkina, N.K.; Sharovarov, G.A.; Shiryaeva, N.M. [Inst. of Radioecological Problems, Minsk (Belarus); Michaelides, E.E.; Melkozerova, O.V. [Tulane Univ., New Orleans, LA (United States)

1995-12-31

338

Development of Plasma Vitrification Technology for Contaminated Soil at the Savannah River Site  

SciTech Connect

The Mixed Waste Integrated Program (MWIP) of the United States Department of Energy`s Office of Technology Development is developing treatment technologies for a wide variety of materials containing mixed low-level waste, i.e., having low levels of radioactivity along with hazardous constituents. Vitrification is a promising treatment technology for many of these wastes, including contaminated soil such as that found at the Savannah River Site. Proof-of-principle tests were performed to demonstrate the feasibility of both ex-situ and in-situ vitrification of contaminated soil by means of a plasma torch. A mixture of 89 percent as-excavated Savannah River Site sandy clay loam with 11 percent lime addition was tested. Vitrification of a mixture of this feed, in a 10 in. diameter crucible with a non-transferred arc plasma torch at a nominal 160 kW, was successful. The process produced homogeneous glass (albeit with local compositional variations), surrounded by a skull of incompletely reacted feed. Characterization of the resultant product durability using the Product Consistency Test showed elemental leaching well below the Environmental Assessment glass (which is often used as a minimum standard of glass acceptability in high-level waste glass assessment) for both the glass and the skull regions. Future tests should include doping the soil with hazardous constituents to enable further verification of the wasteform integrity via the Toxic Characteristic Leaching Procedure. In-situ operation was mimicked in the test crucible by segregating the lime additive from the soil within the crucible. Making full use of the available torch maneuvering capabilities (which would likely exceed those of a torch used in-situ) failed to produce a homogeneous melt. Therefore, intimate mechanical mixture of the additive with the soil appears crucial to the success of SRS soil vitrification, and must be included in design considerations for in-situ operation.

Kielpinski, A.L.; Marra, J.C.; Rogers, V.; Schumacher, R.F. [Westinghouse Savannah River Co., Aiken, SC (United States); Etheridge, J.; Kirkland, R. [Mississippi State Univ., MS (United States). Diagnostic Instrumentation and Analysis Lab.

1995-03-01

339

[The radioecological problems of Eurasia and the sources of radioactive environmental contamination in the former USSR].  

PubMed

There is three major sites of radioactive environmental contamination in the former USSR: the Chelyabinsk region in the Urals, Chernobyl NPP in Ukraine and Novaya Zemlya in the Arctic Ocean. The first mentioned is the most important with regard to local (potential) contamination, the last one dominates the global contamination. A number of sites and sources are less well known with regard to environmental contamination. This is thus the case for the plutonium production factories at Tomsk and Dodonovo. More information on nuclear reactors in lost or dumped submarines is also needed. From a global point of view reliable assessment of the radioactive run-off from land and deposits of nuclear waste in the Arctic Ocean are in particular pertinent. PMID:8469738

Polikarpov, G G; Aarkrog, A

1993-01-01

340

Renewed soil erosion and remobilisation of radioactive sediment in Fukushima coastal rivers after the 2013 typhoons  

PubMed Central

Summer typhoons and spring snowmelt led to the riverine spread of continental Fukushima fallout to the coastal plains of Northeastern Japan and the Pacific Ocean. Four fieldwork campaigns based on measurement of radioactive dose rates in fine riverine sediment that has recently deposited on channel bed-sand were conducted between November 2011 and May 2013 to document the spread of fallout by rivers. After a progressive decrease in the fresh riverine sediment doses rates between 2011 and early spring in 2013, a fifth campaign conducted in November 2013 showed that they started to increase again after the occurrence of violent typhoons. We show that this increase in dose rates was mostly due to remobilization of contaminated material that was temporarily stored in river channels or, more importantly, in dam reservoirs of the region during the typhoons. In addition, supply of particles from freshly eroded soils in autumn 2013 was the most important in areas where decontamination works are under progress. Our results underline the need to monitor the impact of decontamination works and dam releases in the region, as they may provide a continuous source of radioactive contamination to the coastal plains and the Pacific Ocean during the coming years. PMID:24694549

Evrard, Olivier; Chartin, Caroline; Onda, Yuichi; Lepage, Hugo; Cerdan, Olivier; Lefevre, Irene; Ayrault, Sophie

2014-01-01

341

Renewed soil erosion and remobilisation of radioactive sediment in Fukushima coastal rivers after the 2013 typhoons.  

PubMed

Summer typhoons and spring snowmelt led to the riverine spread of continental Fukushima fallout to the coastal plains of Northeastern Japan and the Pacific Ocean. Four fieldwork campaigns based on measurement of radioactive dose rates in fine riverine sediment that has recently deposited on channel bed-sand were conducted between November 2011 and May 2013 to document the spread of fallout by rivers. After a progressive decrease in the fresh riverine sediment doses rates between 2011 and early spring in 2013, a fifth campaign conducted in November 2013 showed that they started to increase again after the occurrence of violent typhoons. We show that this increase in dose rates was mostly due to remobilization of contaminated material that was temporarily stored in river channels or, more importantly, in dam reservoirs of the region during the typhoons. In addition, supply of particles from freshly eroded soils in autumn 2013 was the most important in areas where decontamination works are under progress. Our results underline the need to monitor the impact of decontamination works and dam releases in the region, as they may provide a continuous source of radioactive contamination to the coastal plains and the Pacific Ocean during the coming years. PMID:24694549

Evrard, Olivier; Chartin, Caroline; Onda, Yuichi; Lepage, Hugo; Cerdan, Olivier; Lefèvre, Irène; Ayrault, Sophie

2014-01-01

342

Electrokinetic removal of uranium from contaminated, unsaturated soils  

SciTech Connect

Electrokinetic remediation of uranium-contaminated soil was studied in a series of laboratory-scale experiments in test cells with identical geometry using quartz sand at approximately 10 percent moisture content. Uranium, when present in the soil system as an anionic complex, could be migrated through unsaturated soil using electrokinetics. The distance that the uranium migrated in the test cell was dependent upon the initial molar ratio of citrate to uranium used. Over 50 percent of the uranium was recovered from the test cells using the citrate and carbonate complexing agents over of period of 15 days. Soil analyses showed that the uranium remaining in the test cells had been mobilized and ultimately would have been extracted. Uranium extraction exceeded 90 percent in an experiment that was operated for 37 days. Over 70 percent of the uranium was removed from a Hanford waste sample over a 55 day operating period. Citrate and carbonate ligand utilization ratios required for removing 50 percent of the uranium from the uranium-contaminated sand systems were approximately 230 moles ligand per mole uranium and 1320 moles ligand per mole uranium for the waste. Modifying the operating conditions to increasing the residence time of the complexants is expected to improved the utilization efficiency of the complexing agent.

Booher, W.F. [IT Corp., Albuquerque, NM (United States); Lindgren, E.R.; Brady, P.V. [Sandia National Laboratories, Albuquerque, NM (United States)

1997-01-01

343

Environmental toxicity testing of contaminated soil based on microcalorimetry.  

PubMed

Contaminated site assessment and monitoring requires efficient risk-management tools including innovative environmental toxicity tests. The first application of microcalorimetry for toxicity testing draw the attention to a possible new tool to increase sensitivity, to eliminate matrix effect and to study effect-mechanism. A Thermal Activity Monitor (TAM) microcalorimeter was used for measuring the heat production of various test organisms when getting in contact with sterile toxic soils. Well known bacterial (Azomonas agilis), animal (Folsomia candida) and plant test organisms (Sinapis alba) were tested for heat production. The heat response of selected testorganisms was measured in case of metal (Cu and Zn) and organic pollutant (Diesel oil, DBNPA and PCP) contaminated soils. In addition to the quantitative determination of the heat production, the mechanism of the toxic effect can be characterized from the shape of the power-time curve (slope of the curve, height and time of the maximum). In certain concentration ranges the higher the pollutant concentration of the soil the lower the maximum of the time-heat curve. At low pollutant concentrations an increased heat production was measured in case of A. agile and 20 and 200 mg Zn kg(-1) soil. The microcalorimetric testing was more sensitive in all cases than the traditional test methods. Our results showed that the microcalorimetric test method offers a new and sensitive option in environmental toxicology, both for research and routine testing. PMID:20549622

Gruiz, K; Feigl, V; Hajdu, Cs; Tolner, M

2010-10-01

344

Development of Fungal Inocula for Bioaugmentation of Contaminated Soils  

PubMed Central

This report describes novel fungal inocula for bioaugmentation of soils contaminated with hazardous organic compounds. The inocula are in the form of pelleted solid substrates coated with a sodium alginate suspension of fungal spores or mycelial fragments and incubated until overgrown with the mycelium of selected lignin-degrading fungi. The organisms evaluated were Phanerochaete chrysosporium (BKM F-1767, ATCC 42725), P. sordida (HHB-8922-Sp), Irpex lacteus (Mad-517, ATCC 11245), Bjerkandera adusta (FP-135160-Sp, ATCC 62023), and Trametes versicolor (MD-277). The pelleted fungal inocula resisted competition and proliferation from indigenous soil microbes, were lower in moisture content than current fungal inocula, and had sufficient mechanical strength to allow handling and introduction into the soil without a change in the mechanical consistency of the pellets. Inoculated at a rate of 3% in artificially contaminated nonsterile soil, I. lacteus, B. adusta, and T. versicolor removed 86, 82, and 90%, respectively, of the pentachlorophenol in 4 weeks. A mathematical model was developed to explain moisture distribution in a hydrogel-coated pelleted substrate. PMID:16535337

Lestan, D.; Lamar, R. T.

1996-01-01

345

Acoustically enhanced remediation of contaminated soil and ground water  

SciTech Connect

This program systematically evaluates the use of acoustic excitation fields (AEFs) to increase fluid and contaminant extraction rates from a wide range of unconsolidated soils. Successful completion of this program will result in a commercially-viable, advanced in-situ remediation technology that will significantly reduce clean-up times and costs. This technology should have wide applicability since it is envisioned to augment existing remediation technologies, such as traditional pump and treat and soil vapor extraction, not replace them. The overall program has three phases: Phase 1--laboratory scale parametric investigation; Phase 2--technology scaling study; Phase 3--field demonstration. Phase 1 of the program, corresponding to this period of performance, has as its primary objectives to provide a laboratory-scale proof of concept, and to fully characterize the effects of AEFs on fluid and contaminant extraction rates in a wide variety of soil types. The laboratory measurements of the soil transport properties and process parameters will be used in a computer model of the enhanced remediation process. A Technology Merit and Trade Study will complete Phase 1.

Iovenitti, J.L.; Rynne, T.M.; Spencer, J.W. Jr.

1994-12-31

346

Analytical characterization of contaminated soils from former manufactured gas plants  

SciTech Connect

Detailed analytical characterization of the organic matter (OM) of aged polluted soils from five former manufactured gas plants (MGP) and of two coal tars was completed. It was aimed at obtaining information relevant to the physicochemical state of the polycyclic aromatic hydrocarbon (PAH) pollutants and to their in-situ evolution in time. Overall characterization of total OM (essentially polluting OM) was carried out directly on soil samples with or without prior extraction with solvent. It involved a technique of pyrolysis/oxidation coupled to flame ionization/thermal conductivity detection. Extracts in solvent were fractionated by liquid chromatography into saturated hydrocarbons, PAH, and resins, the first two fractions being further characterized by gas chromatography and mass spectrometry. The compositions of OM of soils were found to be very similar. A total of 28% of organic carbon, including all PAH, was extractable by solvent. The compositions of coal tars were qualitatively similar to those of OM of MGP soils but with a higher proportion (48%) of total extractable OM and of PAH, in particular lower PAH. Contamination of MGP soils appeared essentially as coal tar having undergone natural attenuation. The constant association of PAH with heavy OM in MGP soils is important with respect to the mobility and bioaccessibility of these pollutants.

Haeseler, F. [Inst. Francais du Petrole, Rueil Malmaison (France). Div. Chimie et Physicochimie Appliquees] [Inst. Francais du Petrole, Rueil Malmaison (France). Div. Chimie et Physicochimie Appliquees; [DVGW-Technologiezentrum Wasser, Karlsruhe (Germany); Blanchet, D.; Vandecasteele, J.P. [Inst. Francais du Petrole, Rueil Malmaison (France). Chimie et Physicochimie Appliquees] [Inst. Francais du Petrole, Rueil Malmaison (France). Chimie et Physicochimie Appliquees; Druelle, V. [Gaz De France, La Plaine-Saint-Denis (France). Direction de la Recherche] [Gaz De France, La Plaine-Saint-Denis (France). Direction de la Recherche; Werner, P. [DVGW-Technologiezentrum Wasser, Karlsruhe (Germany)] [DVGW-Technologiezentrum Wasser, Karlsruhe (Germany); [Technische Univ., Dresden, (Germany). Inst. fuer Abfallwirtschaft und Altlasten

1999-03-15

347

Cleaning Polychlorinated Biphenyl (PCB) Contaminated Garden Soil by Phytoremediation  

PubMed Central

A poplar planted system resulted in the complete removal of at least 19 of the 29 potential polychlorinated biphenyl (PCB) congeners detected in trace amounts (37.9 ng g-1 in total) in a commercial garden soil, while the unplanted soil only had 2 congeners completely removed after 96 days. In addition, the most recalcitrant congener, PCB 52, only decreased by 0.1% in the unplanted reactors while declining by 22.3% in the planted system. There was also greater removal of a PCB 77 spike in the planted system when compared to the unplanted system, 17.2% in the planted system versus 2.8% in the unplanted system. The results suggest that phytoremediation may be an effective tool in cleaning commercially available garden soils that are lightly contaminated with PCBs. PMID:24409084

Schnoor, Jerald L.

2013-01-01

348

Implementation of in situ vitrification for contaminated soils  

SciTech Connect

Geosafe Corporation will be implementing the in situ vitrification (ISV) technology commercially at a Superfund site in Michigan. In preparation for the Michigan site, Geosafe Corporation performed two operational acceptance tests (OATs) at the Geosafe Test Site in Richland, Washington. The objectives were to test the performance of the equipment and to train operating personnel. In addition, Geosafe cooperated with the Pacific Northwest Laboratory and the US Department of Energy, Office of Technology Development in a full-scale field data collection effort to obtain data characterizing the dynamic conditions in the soil created by the advancing ISV melt. This full-scale information provides empirical data to support the current understanding of the ISV technology for contaminated soil applications and provides verification of the accuracy of computational modeling tools being used to evaluate the applicability of the ISV technology to different soil sites.

Luey, J.; Roberts, J.S. [Pacific Northwest Lab., Richland, WA (United States); Timmerman, C.L. [Geosafe Corp., Richland, WA (United States)

1993-08-01

349

Evaluation of the phytostabilisation efficiency in a trace elements contaminated soil using soil health indicators.  

PubMed

The efficiency of a remediation strategy was evaluated in a mine soil highly contaminated with trace elements (TEs) by microbiological, ecotoxicological and physicochemical parameters of the soil and soil solution (extracted in situ), as a novel and integrative methodology for assessing recovery of soil health. A 2.5-year field phytostabilisation experiment was carried out using olive mill-waste compost, pig slurry and hydrated lime as amendments, and a native halophytic shrub (Atriplex halimus L.). Comparing with non-treated soil, the addition of the amendments increased soil pH and reduced TEs availability, favoured the development of a sustainable vegetation cover (especially the organic materials), stimulated soil microorganisms (increasing microbial biomass, activity and functional diversity, and reducing stress) and reduced direct and indirect soil toxicity (i.e., its potential associated risks). Therefore, under semi-arid conditions, the use of compost and pig slurry with A. halimus is an effective phytostabilisation strategy to improve soil health of nutrient-poor soils with high TEs concentrations, by improving the habitat function of the soil ecosystem, the reactivation of the biogeochemical cycles of essential nutrients, and the reduction of TEs dissemination and their environmental impact. PMID:24468528

Pardo, T; Clemente, R; Epelde, L; Garbisu, C; Bernal, M P

2014-03-15

350

Mesoscale modelling of radioactive contamination formation in Ukraine caused by the Chernobyl accident  

Microsoft Academic Search

This work is devoted to the reconstruction of time-dependent radioactive contamination fields in the territory of Ukraine in the initial period of the Chernobyl accident using the model of atmospheric transport LEDI (Lagrangian–Eulerian DIffusion model). The modelling results were compared with available 137Cs air and ground contamination measurement data. The 137Cs atmospheric transport over the territory of Ukraine was simulated

Nikolai Talerko

2005-01-01

351

Toxicological responses of earthworm (Eisenia fetida) exposed to metal-contaminated soils.  

PubMed

The aim of this study was to evaluate the toxicological responses of earthworm (Eisenia fetida) induced by field-contaminated, metal-polluted soils. Biochemical responses and DNA damage of earthworm exposed to two multi-metal-contaminated soils in a steel industry park and a natural reference soil in Zijin Mountain for 2, 7, 14, and 28 days were studied. Results showed that three enzyme activities, including superoxide dismutase (SOD), acetylcholinesterase (AChE), and cellulase, in earthworm in metal-contaminated soils were significantly different from those of the reference soil. Cellulase and AChE were more sensitive than SOD to soil contamination. The Olive tail moment of the comet assay after 2-day exposure increased 56.5 and 552.0 % in two contaminated soils, respectively, compared to the reference soil. Our findings show that cellulase and DNA damage levels can be used as potential biomarkers for exposure of earthworm to metal-polluted soils. PMID:23589267

Zheng, Kai; Liu, ZhengTao; Li, YaJie; Cui, YiBin; Li, Mei

2013-12-01

352

PHENOTYPIC RESPONSES OF THE SOIL BACTERIAL COMMUNITY TO POLYCYCLIC AROMATIC HYDROCARBON CONTAMINATION IN SOILS  

Microsoft Academic Search

Five soils with different levels of polycyclic aromatic hydrocarbon (PAH) and metallic contamination were sampled from a former coke facility site located in the north of France. Among PAH-degrading microbiota, naphthalene-degraders were ubiquitous, whereas bacteria-degrading PAHs of more than two rings were present in only the polluted soils, in the range of 1% to 10% of the total microbiota. Phenotypic

C. Lors; J. R. Mossmann; P. Barbé

2004-01-01

353

Modeling arsenic desorption from herbicide-contaminated soils.  

PubMed

The application of arsenical herbicides has created legacy environmental problems by contaminating soil in some agricultural areas and at various industrial sites. Numerous previous studies have suggested that the adsorption of arsenic by common soil components is largely controlled by kinetic factors. Four arsenic-contaminated soil samples collected from industrial sites were characterized and subjected to sequential leaching using a synthetic acid rain solution in order to study the release of arsenic. A dual-site numerical sorption-desorption model was constructed that describes arsenic desorption from these soils in terms of two different release mechanisms: Release from type I (equilibrium) and type II (kinetic) sorption sites. Arsenic held on both type I and II sorption sites is accessible through extensive acid rain leaching. Arsenic desorption from these sites follows a linear Kd model; the manner of approaching the Kd model, however, differs. Arsenic desorption from type I sites reached equilibrium with the aqueous phase under the physical environment provided by the experiment (shaking for 24 h at 25 degrees C), while desorption from type II sites followed a first-order kinetic pattern when approaching equilibrium. During synthetic acid rain sequential leaching of the soils, type I sites released their sorbed arsenic rapidly and subsequent desorption was dominated by the kinetic release of arsenic from type II sites. This shift in desorption mechanism dominance generated data corresponding to two intersecting straight lines in the n-logC dimension for all four soils. The dual-site desorption model was solved analytically and proven to be successful in simulating sorption processes where two different mechanisms are simultaneously controlling the aqueous concentration of a trace element. PMID:19199372

Qi, Yongqiang; Donahoe, Rona J

2009-06-01

354

Soil microbial community responses to antibiotic-contaminated manure under different soil moisture regimes.  

PubMed

Sulfadiazine (SDZ) is an antibiotic frequently administered to livestock, and it alters microbial communities when entering soils with animal manure, but understanding the interactions of these effects to the prevailing climatic regime has eluded researchers. A climatic factor that strongly controls microbial activity is soil moisture. Here, we hypothesized that the effects of SDZ on soil microbial communities will be modulated depending on the soil moisture conditions. To test this hypothesis, we performed a 49-day fully controlled climate chamber pot experiments with soil grown with Dactylis glomerata (L.). Manure-amended pots without or with SDZ contamination were incubated under a dynamic moisture regime (DMR) with repeated drying and rewetting changes of >20 % maximum water holding capacity (WHCmax) in comparison to a control moisture regime (CMR) at an average soil moisture of 38 % WHCmax. We then monitored changes in SDZ concentration as well as in the phenotypic phospholipid fatty acid and genotypic 16S rRNA gene fragment patterns of the microbial community after 7, 20, 27, 34, and 49 days of incubation. The results showed that strongly changing water supply made SDZ accessible to mild extraction in the short term. As a result, and despite rather small SDZ effects on community structures, the PLFA-derived microbial biomass was suppressed in the SDZ-contaminated DMR soils relative to the CMR ones, indicating that dynamic moisture changes accelerate the susceptibility of the soil microbial community to antibiotics. PMID:24743980

Reichel, Rüdiger; Radl, Viviane; Rosendahl, Ingrid; Albert, Andreas; Amelung, Wulf; Schloter, Michael; Thiele-Bruhn, Sören

2014-07-01

355

Dispersal of radioactivity by wildlife from contaminated sites in a forested landscape  

SciTech Connect

Oak Ridge National Laboratory (ORNL) is located within the Valley and Ridge Physiographic Province of eastern Tennessee (USA). Wildlife populations have access to some radioactively contaminated sites at ORNL. Contaminated animals or animal nests within the Laboratory's boundaries have been found to contain {sup 90}Sr or {sup 137}Cs on the order of 10{sup -2}-10{sup 4} Bqg{sup -1} and trace amounts of other radionuclides (including transuranic elements). Animals that are capable of flight and animals with behavior patterns or developmental life stages involving contact with sediments in radioactive ponds, like benthic invertebrates, present the greatest potential for dispersal of radioactivity. The emigration of frogs and turtles from waste ponds also presents a potential for dispersal of radioactivity but over distances < 5 km. Mud-dauber wasps (Hymenoptera) and swallows (Hirundinidae) may transport radioactive mud for nest building, but also over relatively short distances (0.2-1 km). Movement by small mammals is limited by several factors, including physical barriers and smaller home ranges. Larger animals, like white-tailed deer (Odocoileus virginianus), are potential vectors of radioactivity due to their greater body size, longer life expectancy, and larger home range. Larger animals contain greater amounts of total radioactivity than smaller animals, but tissue concentrations of {sup 137}Cs generally decline with body size.

Garten Jr, Charles T [ORNL

1995-12-01

356

Final report: survey and removal of radioactive surface contamination at environmental restoration sites, Sandia National Laboratories/New Mexico. Volume 1  

SciTech Connect

This report describes the survey and removal of radioactive surface contamination at Sandia`s Environmental Restoration (ER) sites. Radiological characterization was performed as a prerequisite to beginning the Resource Conservation and Recovery Act (RCRA) corrective action process. The removal of radioactive surface contamination was performed in order to reduce potential impacts to human health and the environment. The predominant radiological contaminant of concern was depleted uranium (DU). Between October 1993 and November 1996 scanning surface radiation surveys, using gamma scintillometers, were conducted at 65 sites covering approximately 908 acres. A total of 9,518 radiation anomalies were detected at 38 sites. Cleanup activities were conducted between October 1994 and November 1996. A total of 9,122 anomalies were removed and 2,072 waste drums were generated. The majority of anomalies not removed were associated with a site that has subsurface contamination beyond the scope of this project. Verification soil samples (1,008 total samples) were collected from anomalies during cleanup activities and confirm that the soil concentration achieved in the field were far below the target cleanup level of 230 pCi/g of U-238 (the primary constituent of DU) in the soil. Cleanup was completed at 21 sites and no further radiological action is required. Seventeen sites were not completed since cleanup activities wee precluded by ongoing site activity or were beyond the original project scope.

Lambert, K.A.; Mitchell, M.M. [Brown and Root Environmental, Albuquerque, NM (United States); Jean, D. [MDM/Lamb, Inc., Albuquerque, NM (United States); Brown, C. [Environmental Dimensions, Inc., Albuquerque, NM 87109 (United States); Byrd, C.S. [Sandia National Labs., Albuquerque, NM (United States)

1997-09-01

357

REMEDIATION OF SOILS CONTAMINATED WITH WOOD-TREATMENT CHEMICALS (PCP AND CREOSOTE)  

EPA Science Inventory

PCP and creosote PAHs are found in most of the contaminated soils at wood-treatment sites. The treatment methods currently being used for such soils include soil washing, incineration, and biotreatment. Soil washing involves removal of the hazardous chemicals from soils ...

358

Efficacy of indigenous soil microbes in arsenic mitigation from contaminated alluvial soil of India.  

PubMed

Selected arsenic-volatilizing indigenous soil bacteria were isolated and their ability to form volatile arsenicals from toxic inorganic arsenic was assessed. Approximately 37 % of AsIII (under aerobic conditions) and 30 % AsV (under anaerobic conditions) were volatilized by new bacterial isolates in 3 days. In contrast to genetically modified organism, indigenous soil bacteria was capable of removing 16 % of arsenic from contaminated soil during 60 days incubation period while applied with a low-cost organic nutrient supplement (farm yard manure). PMID:23443943

Majumder, Aparajita; Bhattacharyya, Kallol; Kole, S C; Ghosh, Sagarmoy

2013-08-01

359

Phytoremediation of soil contaminated with cadmium, copper and polychlorinated biphenyls.  

PubMed

A pot experiment and afield trial were conducted to study the remediation of an aged field soil contaminated with cadmium, copper and polychlorinated biphenyls (PCBs) (7.67 +/- 0.51 mg kg(-1) Cd, 369 +/- 1 mg kg(-1) Cu in pot experiment; 8.46 +/- 0.31 mg kg(-1) Cd, 468 +/- 7 mg kg(-1) Cu, 323 +/- 12 microg kg(-1) PCBs for field experiment) under different cropping patterns. In the pot experiment Sedum plumbizincicola showed pronounced Cd phytoextraction. After two periods (14 months) of cropping the Cd removal rates in these two treatments were 52.2 +/- 12.0 and 56.1 +/- 9.1%, respectively. Total soil PCBs in unplanted control pots decreased from 323 +/- 11 to 49.3 +/- 6.6 microg kg(-1), but with no significant difference between treatments. The field microcosm experiment intercropping of three plant species reduced the yield of S. plumbizincicola, with a consequent decrease in soil Cd removal. S. plumbizincicola intercropped with E. splendens had the highest shoot Cd uptake (18.5 +/- 1.8 mg pot(-1)) after 6 months planting followed by intercropping with M. sativa (15.9 +/- 1.9 mg pot(-1)). Liming with S. plumbizincicola intercropped with M. sativa significantly promoted soil PCB degradation by 25.2%. Thus, adjustment of soil pH to 5.56 combined with intercropping with S. plumbizincicola and M. sativagave high removal rates of Cd, Cu, and PCBs. PMID:22908627

Wu, Longhua; Li, Zhu; Han, Cunliang; Liu, Ling; Teng, Ying; Sun, Xianghui; Pan, Cheng; Huang, Yujuan; Luo, Yongming; Christie, Peter

2012-07-01

360

Toxicity Assessment of Contaminated Soils of Solid Domestic Waste Landfill  

NASA Astrophysics Data System (ADS)

The paper delivers the analysis of an 18-year dynamic pattern of land pollutants concentration in the soils of a solid domestic waste landfill. It also presents the composition of the contaminated soils from different areas of the waste landfill during its operating period. The authors calculate the concentrations of the following pollutants: chrome, nickel, tin, vanadium, lead, cuprum, zinc, cobalt, beryllium, barium, yttrium, cadmium, arsenic, germanium, nitrate ions and petrochemicals and determine a consistent pattern of their spatial distribution within the waste landfill area as well as the dynamic pattern of their concentration. Test-objects are used in experiments to make an integral assessment of the polluted soil's impact on living organisms. It was discovered that the soil samples of an animal burial site are characterized by acute toxicity while the area of open waste dumping is the most dangerous in terms of a number of pollutants. This contradiction can be attributed to the synergetic effect of the polluted soil, which accounts for the regularities described by other researchers.

Pasko, O. A.; Mochalova, T. N.

2014-08-01

361

Risk of antibiotic resistance from metal contaminated soils  

NASA Astrophysics Data System (ADS)

It is known that contaminated soils can lead to increased incidence of illness and disease, but it may also prevent our ability to fight disease. Many antibiotic resistant genes (ARG) acquired by bacteria originate from the environment. It is important to understand factors that influence levels of ARG in the environment, which could affect us clinically and agriculturally. The presence of elevated metal content in soils often promotes antibiotic resistance in exposed microorganisms. Using qPCR, the abundances of ARG to compare levels with geochemical conditions in randomly selected soils from several countries. Many ARG positively correlated with soil metal content, especially copper, chromium, nickel, lead, and iron. Results suggest that geochemical metal conditions influence the potential for antibiotic resistance in soil, which might be used to estimate baseline gene presence on various landscape scales and may translate to epidemiological risk of antibiotic-resistance transmission from the environment. This suggests that we may have to reconsider tolerances of metal pollution in the environment.

Knapp, Charles

2013-04-01

362

Soil contamination by organic and inorganic pollutants at the regional scale: the case of Piedmont, Italy  

Microsoft Academic Search

Background, aim, and scope  Diffuse soil contamination has often been neglected in scientific literature, as most studies focus on contaminants from point-sources\\u000a (either of industrial or agricultural origin). However, soil pollution from diffuse sources is recognized as one of the major\\u000a soil threats by the EU Soil Thematic Strategy. In fact, some pollutants are nowadays ubiquitarious in the soil system, and

Gabriele Fabietti; Mattia Biasioli; Renzo Barberis; Franco Ajmone-Marsan

2010-01-01

363

Contaminant transport in soil with depth-dependent reaction coefficients and time-dependent boundary conditions.  

PubMed

Predicting the fate and movement of contaminant in soils and groundwater is essential to assess and reduce the risk of soil contamination and groundwater pollution. Reaction processes of contaminant often decreased monotonously with depth. Time-dependent input sources usually occurred at the inlet of natural or human-made system such as radioactive waste disposal site. This study presented a one-dimensional convection-dispersion equation (CDE) for contaminant transport in soils with depth-dependent reaction coefficients and time-dependent inlet boundary conditions, and derived its analytical solution. The adsorption coefficient and degradation rate were represented as sigmoidal functions of soil depth. Solute breakthrough curves (BTCs) and concentration profiles obtained from CDE with depth-dependent and constant reaction coefficients were compared, and a constant effective reaction coefficient, which was calculated by arithmetically averaging the depth-dependent reaction coefficient, was proposed to reflect the lumped depth-dependent reaction effect. With the effective adsorption coefficient and degradation rate, CDE could produce similar BTCs and concentration profiles as those from CDE with depth-dependent reactions in soils with moderate chemical heterogeneity. In contrast, the predicted concentrations of CDE with fitted reaction coefficients at a certain depth departed significantly from those of CDE with depth-dependent reactions. Parametric analysis was performed to illustrate the effects of sinusoidally and exponentially decaying input functions on solute BTCs. The BTCs and concentration profiles obtained from the solutions for finite and semi-infinite domain were compared to investigate the effects of effluent boundary condition. The finite solution produced higher concentrations at the increasing limb of the BTCs and possessed a higher peak concentration than the semi-infinite solution which had a slightly long tail. Furthermore, the finite solution gave a higher concentration in the immediate vicinity of the exit boundary than the semi-infinite solution. The applicability of the proposed model was tested with a field herbicide and tracer leaching experiment in an agricultural area of northeastern Greece. The simulation results indicated that the proposed CDE with depth-dependent reaction coefficients was able to capture the evolution of metolachlor concentration at the upper soil depths. However, the simulation results at deep depths were not satisfactory as the proposed model did not account for preferential flow observed in the field. PMID:23490106

Gao, Guangyao; Fu, Bojie; Zhan, Hongbin; Ma, Ying

2013-05-01

364

Effect of Bile Type on the Bioaccessibility of Soil Contaminants in an In Vitro Digestion Model  

Microsoft Academic Search

Soil ingestion is an important pathway of exposure for many nonvolatile contaminants for man and in particular for children. A fraction of the ingested contaminant may not dissociate from the soil particles during digestion in the gastro-intestinal tract, and is thus not available for transport across the intestinal epithelium. In order to estimate the contaminant fraction that is mobilized from

A. G. Oomen; C. J. M. Rompelberg; E. Van de Kamp; D. P. K. H. Pereboom; L. L. De Zwart; A. J. A. M. Sips

2004-01-01

365

Predicting Fate and Transport of Contaminants in the Vadose Zone using a Soil Screening Model  

Microsoft Academic Search

Soil Screening Levels (SSLs) are threshold concentrations below which there is no concern for the migration of residual soil contaminants to the aquifer above maximum contaminant levels (MCLs). At sites where contaminant concentrations exceed SSLs, further study maybe warranted under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). SSLs are based upon simplified fate and transport assumptions, but the

Rucker

2002-01-01

366

The use of molecular techniques to characterize the microbial communities in contaminated soil and water  

Microsoft Academic Search

Traditionally, the identification and characterization of microbial communities in contaminated soil and water has previously been limited to those microorganisms that are culturable. The application of molecular techniques to study microbial populations at contaminated sites without the need for culturing has led to the discovery of unique and previously unrecognized microorganisms as well as complex microbial diversity in contaminated soil

Seidu Malik; Michael Beer; Mallavarapu Megharaj; Ravi Naidu

2008-01-01

367

Spatial Data Analysis and Modeling of Radioactively-Contaminated Territories: Lessons Learned from Chernobyl  

E-print Network

Chernobyl M. Kanevski1 , L. Bolshov2 , V. Demyanov3 , E. Savelieva4 , V. Timonin5 , S. Chernov6 Abstract territories after the Chernobyl accident. The Chernobyl accident resulted in radioactive contamination, concerning environmental spatial data analysis. The spatial patterns of the Chernobyl fallout are very

368

Technical basis for EPA`s proposed regulation on the cleanup of sites contaminated with radioactivity  

Microsoft Academic Search

The US Environmental Protection Agency is proposing a regulation for the protection of the public and radioactive contamination at sites that are to be cleaned up and released for public use. The rule will apply to sites under the control of Federal agencies, and will impose limits on radiation doses to individuals living or working on a site following cleanup;

A. B. Wolbarst; M. E. Clark; M. Doehnert; D. Back; J. W. Bartlett; D. Beres; D. Chan; E. Durman; S. Hay; H. B. Hull; N. Lailas; J. MacKinney; L. Ralston; P. L. Tsirigotis

1996-01-01

369

FINAL REPORT: REAL-TIME IDENTIFICATION AND CHARACTERIZATION OF ASBESTOS AND CONCRETE MATERIALS WITH RADIOACTIVE CONTAMINATION  

EPA Science Inventory

Concrete and asbestos-containing materials were widely used in DOE building construction in the 1940s and 1950s. Over the years, many of these porous materials have been contaminated with radioactive sources, on and below the surface. To improve current practice in identifying ha...

370

t -software package for numerical simulations of radioactive contaminant transport in groundwater  

E-print Network

equations that arise from the modelling of radioactive contaminant transport in porous media. It can solve be realised. 1 Introduction The software package r3 t (radionuclides, reactions, retardation and transport- water. The general mathematical model includes not only transport by advection, diffusion and dispersion

Frolkovic, Peter

371

Genetic consequences of radioactive contamination by the Chernobyl fallout to agricultural crops  

Microsoft Academic Search

The genetic consequences of radioactive contamination by the fallout to agricultural crops after the accident at the Chernobyl NPP in 1986 have been studied. In the first, acute, period of this accident, when the absorbed dose was primarily due to external ?- and ?-irradiation, the radiation injury of agricultural crops, according to the basic cytogenetic tests, resembled the effect produced

S. A. Geraskin; V. G. Dikarev; Ye. Ya. Zyablitskaya; A. A. Oudalova; Ye. V Spirin; R. M. Alexakhin

2003-01-01

372

Arsenic and chromium speciation in an urban contaminated soil.  

PubMed

The distribution and speciation of As and Cr in a contaminated soil were studied by synchrotron-based X-ray microfluorescence (?-XRF), microfocused X-ray absorption spectroscopy (?-XAS), and bulk extended X-ray absorption fine structure spectroscopy (EXAFS). The soil was taken from a park in Wilmington, DE, which had been an important center for the leather tanning industry along the Atlantic seaboard of the United States, until the early 20th century. Soil concentrations of As, Cr, and Pb measured at certain locations in the park greatly exceeded the background levels of these heavy metals in the State of Delaware. Results show that Cr(III) and As(V) species are mainly present in the soil, with insignificant amounts of Cr(VI) and As(III). Micro-XRF maps show that Cr and Fe are distributed together in regions where their concentrations are diffuse, and at local spots where their concentrations are high. Iron oxides, which can reduce Cr(VI) to Cr(III), are present at some of these hot spots where Cr and Fe are highly concentrated. Arsenic is mainly associated with Al in the soil, and to a minor extent with Fe. Arsenate may be sorbed to aluminum oxides, which might have transformed after a long period of time into an As-Al precipitate phase, having a structure and chemical composition similar to mansfieldite (AlAsO(4)?2H(2)O). The latter hypothesis is supported by the fact that only a small amount of As present in the soil was desorbed using the characteristic toxicity leaching procedure tests. This suggests that As is immobilized in the soil. PMID:22520924

Landrot, Gautier; Tappero, Ryan; Webb, Samuel M; Sparks, Donald L

2012-08-01

373

Soil & Sediment Contamination, 17:137149, 2008 Copyright Taylor & Francis Group, LLC  

E-print Network

Soil & Sediment Contamination, 17:137­149, 2008 Copyright © Taylor & Francis Group, LLC ISSN: 1532 of the Human Health Risks of Asbestos in Soils FRANK A. SWARTJES1 AND PETER C. TROMP2 1 National Institute, Apeldoorn, The Netherlands A tiered approach for the assessment of human health risks of soil contamination

Ahmad, Sajjad

374

APPLICATION OF STEAM INJECTION/VACUUM EXTRACTION TREATMENT SYSTEMS TO CONTAMINATED SOILS  

EPA Science Inventory

Steam Injection/Vacuum Extraction (SIVE) is a method to enable vacuum extraction to treat soils contaminated with semivolatile organic compounds (SVOCS) and to speed the cleanup of soils contaminated with volatile organic compounds (VOCs). he steam injection raises the soil tempe...

375

SOILS, SEC 3 REMEDIATION AND MANAGEMENT OF CONTAMINATED OR DEGRADED LANDS RESEARCH ARTICLE  

E-print Network

SOILS, SEC 3 · REMEDIATION AND MANAGEMENT OF CONTAMINATED OR DEGRADED LANDS · RESEARCH ARTICLE Accumulation and availability of copper in citrus grove soils as affected by fungicide application Jinghua Fan contamination in agricultural soils. However, limited information is available regarding Cu accumulation

Ma, Lena

376

Bioremediation and Biodegradation In Situ Reduction of Chromium(VI) in Heavily Contaminated Soils  

E-print Network

to remediating Cr(VI)-con- taminated soils involves accelerating in situ reductionChromium has becomeBioremediation and Biodegradation In Situ Reduction of Chromium(VI) in Heavily Contaminated Soils an important soil contaminant at many to Cr(III) (Higgins et al., 1998). Enhanced in situ Cr

Hazen, Terry

377

Assessing the bioavailability and risk from metal contaminated soils and dusts#  

EPA Science Inventory

Exposure to contaminated soil and dust is an important pathway in human and ecological risk assessment and often is the "risk-driver" for metal contaminated soil. Site-specific soil physical and chemical characteristics, as well as biological factors, determine the bioavailabilit...

378

Uptake of thallium from artificially contaminated soils by kale (Brassica oleracea L. var. acephala)  

Microsoft Academic Search

A pot experiment focused on the study of factors influencing thallium transfer from contaminated soils into kale (green cabbage, Brassica oleracea L. var. acephala, variety Winterbor F1) was evaluated. Three different types of topsoils with naturally low content of thallium (heavy, medium and medium-light soil) were used for pot experi- ments. The soils were contaminated with thallium sulfate to achieve

J. Pavlí?ková; J. Zbíral; M. Smatanová; P. Habarta; P. Houserová; V. Kubá?

2006-01-01

379

Effects of Incubation and Phosphate Rock on Lead Extractabilityand Speciation in Contaminated Soils  

E-print Network

with the stability constant of the complexes. The combination of the first three listed chemical forms in soils- chemical speciation of Pb-contaminated soils can be a useful tool in evaluating Pb availability. T BADisEffects of Incubation and Phosphate Rock on Lead Extractabilityand Speciation in Contaminated Soils

Ma, Lena

380

Quality of trace element contaminated soils amended with compost under fast growing tree Paulownia fortunei plantation.  

PubMed

The use of fast growing trees could be an alternative in trace element contaminated soils to stabilize these elements and improve soil quality. In this study we investigate the effect of Paulownia fortunei growth on trace element contaminated soils amended with two organic composts under semi-field conditions for a period of 18 months. The experiment was carried out in containers filled with tree different soils, two contaminated soils (neutral AZ and acid V) and a non contaminated soil, NC. Three treatments per soil were established: two organic amendments (alperujo compost, AC, and biosolid compost, BC) and a control without amendment addition. We study parameters related with fertility and contamination in soils and plants. Paulownia growth and amendments increased pH in acid soils whereas no effect of these factors was observed in neutral soils. The plant and the amendments also increased organic matter and consequently, soil fertility. Positive results were also found in soils that were only affected by plant growth (without amendment). A general improvement of "soil biochemical quality" was detected over time and treatments, confirming the positive effect of amendments plus paulownia. Even in contaminated soils, except for Cu and Zn, trace element concentrations in leaves were in the normal range for plants. Results of this mid-term study showed that Paulownia fortunei is a promising species for phytoremediation of trace element polluted soils. PMID:24950211

Madejón, P; Xiong, J; Cabrera, F; Madejón, E

2014-11-01

381

Phytotoxicity of trace metals in spiked and field-contaminated soils: Linking soil-extractable metals with toxicity.  

PubMed

Soil tests have been widely developed to predict trace metal uptake by plants. The prediction of metal toxicity, however, has rarely been tested. The present study was set up to compare 8 established soil tests for diagnosing phytotoxicity in contaminated soils. Nine soils contaminated with Zn or Cu by metal mining, smelting, or processing were collected. Uncontaminated reference soils with similar soil properties were sampled, and series of increasing contamination were created by mixing each with the corresponding soil. In addition, each reference soil was spiked with either ZnCl2 or CuCl2 at several concentrations. Total metal toxicity to barley seedling growth in the field-contaminated soils was up to 30 times lower than that in corresponding spiked soils. Total metal (aqua regia-soluble) toxicity thresholds of 50% effective concentrations (EC50) varied by factors up to 260 (Zn) or 6 (Cu) among soils. For Zn, variations in EC50 thresholds decreased as aqua regia?>?0.43?M HNO3? >?0.05?M ethylenediamine tetraacetic acid (EDTA)?>?1?M NH4 NO3? >?cobaltihexamine?>?diffusive gradients in thin films (DGT)?>?0.001?M CaCl2 , suggesting that the last extraction is the most robust phytotoxicity index for Zn. The EDTA extraction was the most robust for Cu-contaminated soils. The isotopically exchangeable fraction of the total soil metal in the field-contaminated soils markedly explained the lower toxicity compared with spiked soils. The isotope exchange method can be used to translate soil metal limits derived from soils spiked with metal salts to site-specific soil metal limits. Environ Toxicol Chem 2014;33:2479-2487. © 2014 SETAC. PMID:25053440

Hamels, Fanny; Malevé, Jasmina; Sonnet, Philippe; Kleja, Dan Berggren; Smolders, Erik

2014-11-01

382

Radiological Dose Assessment - Nonuniform Skin Dose, Radioactive Skin Contamination, and Multiple Dosimetry  

SciTech Connect

Radioactive skin contamination with {beta}- and {gamma}-emitting radionuclides may result in biologically significant absorbed doses to the skin. A specific exposure scenario of interest is a nonuniform skin dose delivered by {beta}- and {gamma}-emissions from radioactive skin contamination. The United States Department of Energy requires a formal evaluation and reporting of nonuniform skin doses. The United States Department of Energy also requires specific, formal procedures for evaluating the results from the placement or use of multiple dosimeters. Action levels relative to potential absorbed doses for the contamination survey instrumentation in use at Los Alamos and formal procedures for evaluating nonuniform skin doses and multiple dosimeters are developed and presented here.

W. C. Inkret; M. E. Schillaci

1999-03-01

383

Dispersal of radioactivity by wildlife from contaminated sites in a forested landscape  

SciTech Connect

Oak Ridge National Laboratory (ORNL) is located within the Ridge and Valley physiographic province of eastern Tennessee (USA). This area is characterized by deciduous forests dominated by hardwood and mixed mesophytic tree species. Wildlife populations have access to some radioactively contaminated sites at ORNL, and contaminated animals or animal nests within the Laboratory`s boundaries have been found to contain on the order of 10{sup {minus}12} to 10{sup {minus}6} Ci/g of {sup 90}Sr or {sup 137}Cs, and trace amounts of other radionuclides (including transuranic elements). Theoretical calculations indicate that nanocurie levels of {sup 90}Sr in bone can arise from relatively small amounts (1%) of contaminated browse vegetation in a deer`s diet. Measures that have been undertaken at ORNL to curtail the dispersal of radioactivity by animals are briefly reviewed.

Garten, C.T. Jr.

1992-03-27

384

Dispersal of radioactivity by wildlife from contaminated sites in a forested landscape  

SciTech Connect

Oak Ridge National Laboratory (ORNL) is located within the Ridge and Valley physiographic province of eastern Tennessee (USA). This area is characterized by deciduous forests dominated by hardwood and mixed mesophytic tree species. Wildlife populations have access to some radioactively contaminated sites at ORNL, and contaminated animals or animal nests within the Laboratory's boundaries have been found to contain on the order of 10{sup {minus}12} to 10{sup {minus}6} Ci/g of {sup 90}Sr or {sup 137}Cs, and trace amounts of other radionuclides (including transuranic elements). Theoretical calculations indicate that nanocurie levels of {sup 90}Sr in bone can arise from relatively small amounts (1%) of contaminated browse vegetation in a deer's diet. Measures that have been undertaken at ORNL to curtail the dispersal of radioactivity by animals are briefly reviewed.

Garten, C.T. Jr.

1992-03-27

385

Contribution from the Yenisei River to the total radioactive contamination of the Kara Sea  

SciTech Connect

An attempt is made to estimate the contribution from the Yenisei River and, therefore, the Krasnoyarsk Mining and Chemical Plant (MCP), which discharged wastewaters to the Yenisei, to the total contamination of the Kara Sea using results from a study of the radioactive contamination of the Yenisei River, Yenisei Bay, Yenisei Gulf, and the Kara Sea itself. Radionuclides generated from using river water in cooling circuits of production reactors make the largest contribution to the total activity. The radioactive contamination of the river decreased by more than 20 times after two of the three operating reactors were shut down. Only several wetlands are actually affected by MCP hundreds of kilometers from the discharge point.

Kuznetsov, Yu.V.; Revenko, Yu.A.; Legin, V.K. [V.G. Khlopin Radium Institute, St. Petersburg (Russian Federation)] [and others

1995-07-01

386

Research Spotlight: Potential pathways of radioactive contaminants to surface waters  

NASA Astrophysics Data System (ADS)

From the 1940s to the end of the Cold War, the U.S. Department of Energy maintained production facilities for manufacturing nuclear weapons along the Columbia River north of Richland, Wash. Known as the Hanford Site, the Rhode Island-sized area contains more than 53 million gallons of radioactive waste and is the location of a massive environmental cleanup. Of particular concern is that when the facility was active, fluids containing 33-59 tons of uranium were discharged into the shallow subsurface aquifer underneath Hanford. Studies suggest that this pollution is pervasively moving with the groundwater in the direction of the Columbia River. (Water Resources Research, doi:10.1029/2010WR009110, 2010)

Kumar, Mohi

2011-02-01

387

Application, chemistry, and environmental implications of contaminant-immobilization amendments on agricultural soil and water quality.  

PubMed

Contaminants such as nitrogen (N), phosphorus (P), dissolved organic carbon (DOC), arsenic (As), heavy metals, and infectious pathogens are often associated with agricultural systems. Various soil and water remediation techniques including the use of chemical amendments have been employed to reduce the risks associated with these contaminants. This paper reviews the use of chemical amendments for immobilizing principal agricultural contaminants, the chemistry of contaminant immobilization, and the environmental consequences associated with the use of these chemical products. The commonly used chemical amendments were grouped into aluminum-, calcium-, and iron-containing products. Other products of interest include phosphorus-containing compounds and silicate clays. Mechanisms of contaminant immobilization could include one or a combination of the following: surface precipitation, adsorption to mineral surfaces (ion exchange and formation of stable complexes), precipitation as salts, and co-precipitation. The reaction pH, redox potential, clay minerals, and organic matter are potential factors that could control contaminant-immobilization processes. Reviews of potential environmental implications revealed that undesirable substances such as trace elements, fluoride, sulfate, total dissolved solids, as well as radioactive materials associated with some industrial wastes used as amendment could be leached to ground water or lost through runoff to receiving water bodies. The acidity or alkalinity associated with some of the industrial-waste amendments could also constitute a substantial environmental hazard. Chemical amendments could introduce elements capable of inducing or affecting the activities of certain lithotrophic microbes that could influence vital geochemical processes such as mineral dissolution and formation, weathering, and organic matter mineralization. PMID:20832118

Udeigwe, Theophilus K; Eze, Peter N; Teboh, Jasper M; Stietiya, Mohammed H

2011-01-01

388

Modification of soil microbial activity and several hydrolases in a forest soil artificially contaminated with copper  

NASA Astrophysics Data System (ADS)

Soils have long been exposed to the adverse effects of human activities, which negatively affect soil biological activity. As a result of their functions and ubiquitous presence microorganisms can serve as environmental indicators of soil pollution. Some features of soil microorganisms, such as the microbial biomass size, respiration rate, and enzyme activity are often used as bioindicators of the ecotoxicity of heavy metals. Although copper is essential for microorganisms, excessive concentrations have a negative influence on processes mediated by microorganisms. In this study we measured the response of some microbial indicators to Cu pollution in a forest soil, with the aim of evaluating their potential for predicting Cu contamination. Samples of an Ah horizon from a forest soil under oakwood vegetation (Quercus robur L.) were contaminated in the laboratory with copper added at different doses (0, 120, 360, 1080 and 3240 mg kg-1) as CuCl2×2H2O. The soil samples were kept for 7 days at 25 °C and at a moisture content corresponding to the water holding capacity, and thereafter were analysed for carbon and nitrogen mineralization capacity, microbial biomass C, seed germination and root elongation tests, and for urease, phosphomonoesterase, catalase and ß-glucosidase activities. In addition, carbon mineralization kinetics were studied, by plotting the log of residual C against incubation time, and the metabolic coefficient, qCO2, was estimated. Both organic carbon and nitrogen mineralization were lower in polluted samples, with the greatest decrease observed in the sample contaminated with 1080 mg kg-1. In all samples carbon mineralization followed first order kinetics; the C mineralization constant was lower in contaminated than in uncontaminated samples and, in general, decreased with increasing doses of copper. Moreover, it appears that copper contamination not only reduced the N mineralization capacity, but also modified the N mineralization process, since in the contaminated samples all of the inorganic nitrogen was present as ammonium, probably because of inhibition of nitrification. There was a marked decrease in biomass-C with addition of copper, and the decrease was more acute at intermediate doses (average decrease, 73%). Despite the decreases in microbial biomass and mineralized C, the value of qCO2 increased after the addition of copper. Urease activity was strongly affected by the presence of copper and the decrease was proportional to the dose; the activity at the highest dose was only 96% of that in the uncontaminated sample. Phosphomonoesterase activity was also affected by addition of copper; the reduction in activity was less than for urease and the greatest reduction was observed for the dose of 1080 mg kg-1 of copper. Catalase activity was affected by the contamination, but no clear trend was observed in relation to the dose of copper. ß-glucosidase was scarcely modified by the contamination but an increase in activity was observed at the highest dose of copper. Seed germination was not affected by copper contamination, since it only showed a clear decrease for the sample contaminated with the highest dose of copper, while root elongation decreased sharply with doses higher than 120 mg kg-1 of copper. The combined germination-elongation index followed a similar pattern to that of root elongation. For all investigated properties showing a reduction of more than 50%, the response to copper contamination was fitted to a sigmoidal dose-response model, in order to estimate the ED50 values. The ED50 values were calculated for microbial biomass, urease, root elongation and germination-elongation index, and similar values were obtained, ranging from 340 to 405 mg kg-1 Cu. The ED50 values may therefore provide a good estimation of soil deterioration.

Bellas, Rosa; Leirós, M? Carmen; Gil-Sotres, Fernando; Trasar-Cepeda, Carmen

2010-05-01

389

Biochemical remediation of a TNT contaminated soil. Doctoral thesis  

SciTech Connect

This research presents the first field evidence for the phytoremediation of a TNT contaminated soil by the emersed aquatic plant, Myriophyllum brasiliense. Commonly known as Parrotfeather, this plant features a nitroreductase enzyme capable of promoting the reduction of the nitro groups on TNT to the corresponding amino groups. The proposed reductive pathway takes the TNT through isomers of monoamino and diamino to the final triaminonitrotoluene (TNT) Once in the TAT form and in the presence of oxygen, the final oxidative step quickly yields ring opened products and complete phytoremediation of TNT.

Young, D.G.

1995-06-01

390

Vertical characterization of soil contamination using multi-way modeling--a case study.  

PubMed

This study describes application of chemometric multi-way modeling approach to analyze the dataset pertaining to soils of industrial area with a view to assess the soil/sub-soil contamination, accumulation pathways and mobility of contaminants in the soil profiles. The three-way (sampling depths, chemical variables, sampling sites) dataset on heavy metals in soil samples collected from three different sites in an industrial area, up to a depth of 60 m each was analyzed using three-way Tucker3 model validated for stability and goodness of fit. A two component Tucker3 model, explaining 66.6% of data variance, allowed interpretation of the data information in all the three modes. The interpretation of core elements revealing interactions among the components of different modes (depth, variables, sites) allowed inferring more realistic information about the contamination pattern of soils both along the horizontal and vertical coordinates, contamination pathways, and mobility of contaminants through soil profiles, as compared to the traditional data analysis techniques. It concluded that soils at site-1 and site-2 are relatively more contaminated with heavy metals of both the natural as well as anthropogenic origins, as compared to the soil of site-3. Moreover, the accumulation pathways of metals for upper shallow layers and deeper layers of soils in the area were differentiated. The information generated would be helpful in developing strategies for remediation of the contaminated soils for reducing the subsequent risk of ground-water contamination in the study region. PMID:18044006

Singh, Kunwar P; Malik, Amrita; Basant, Ankita; Ojha, Priyanka

2008-11-01

391

[Study on composite stabilization of arsenic (As) contaminated soil].  

PubMed

Since the contaminated soil may contain various kinds of heavy metals, use of single chemical reagent leads to poor remediation and high cost. In this study, soil containing As, Zn, Cd was sampled, and different reagents were selected to carry out the rapid stabilization of contaminated soil. The TCLP (toxicity characteristic leaching procedure) was used to evaluate the leachate toxicity of heavy metals and the results indicated that calcium-containing, sulphur-containing and iron-containing reagents had good performance in reducing the metal mobility. The stabilization efficiency of the six reagents tested ranked in the order of CaO > Na2S > organic sulfur > Chitosan > FeSO4 > (C2H5)2NCS2Na. Two types of reagents (six reagents) were combined based on the target properties of different reagents and the stabilization efficiency was evaluated and analyzed. The results indicated that the composite reagents had higher stabilization efficiency: the efficiency of 3% FeSO4 + 5% CaO was 81.7%, 97.2% and 68.2% for As, Cd and Zn, respectively, and the efficiency of 3% CaO + 5% organic sulfur was 76.6%, 95.7% and 93.8% for these three metals, respectively. Speciation analysis was carried out in this study and the results suggested that it was the change of metals from the exchangeable state to the reduction (for inorganic reagent) or oxidation state (for organic reagent) that caused the soil stabilization and the degree of change determined the stabilization efficiency. PMID:24289009

Wang, Hao; Pan, Li-xiang; Zhang, Xiang-yu; Li, Meng; Song, Bao-hua

2013-09-01

392

Natural radioactivity content in soil and indoor air of Chellanam.  

PubMed

Contribution of terrestrial radiation due to the presence of naturally occurring radionuclides in soil and air constitutes a significant component of the background radiation exposure to the population. The concentrations of natural radionuclides in the soil and indoor air of Chellanam were investigated with an aim of evaluating the environmental radioactivity level and radiation hazard to the population. Chellanam is in the suburbs of Cochin, with the Arabian Sea in the west and the Cochin backwaters in the east. Chellanam is situated at ?25 km from the sites of these factories. The data obtained serve as a reference in documenting changes to the environmental radioactivity due to technical activities. Soil samples were collected from 30 locations of the study area. The activity concentrations of (232)Th, (238)U and (40)K in the samples were analysed using gamma spectrometry. The gamma dose rates were calculated using conversion factors recommended by UNSCEAR [United Nations Scientific Committee on the Effects of Atomic Radiation. Sources and effects of ionizing radiation. UNSCEAR (2000)]. The ambient radiation exposure rates measured in the area ranged from 74 to 195 nGy h(-1) with a mean value of 131 nGy h(-1). The significant radionuclides being (232)Th, (238)U and (40)K, their activities were used to arrive at the absorbed gamma dose rate with a mean value of 131 nGy h(-1) and the radium equivalent activity with a mean value of 162 Bq kg(-1). The radon progeny levels varied from 0.21 to 1.4 mWL with a mean value of 0.6 mWL. The thoron progeny varied from 0.34 to 2.9 mWL with a mean value of 0.85 mWL. The ratio between thoron and radon progenies varied from 1.4 to 2.3 with a mean of 1.6. The details of the study, analysis and results are discussed. PMID:22951996

Mathew, S; Rajagopalan, M; Abraham, J P; Balakrishnan, D; Umadevi, A G

2012-11-01

393

Bioremediation treatment of hydrocarbon-contaminated Arctic soils: influencing parameters.  

PubMed

The Arctic environment is very vulnerable and sensitive to hydrocarbon pollutants. Soil bioremediation is attracting interest as a promising and cost-effective clean-up and soil decontamination technology in the Arctic regions. However, remoteness, lack of appropriate infrastructure, the harsh climatic conditions in the Arctic and some physical and chemical properties of Arctic soils may reduce the performance and limit the application of this technology. Therefore, understanding the weaknesses and bottlenecks in the treatment plans, identifying their associated hazards, and providing precautionary measures are essential to improve the overall efficiency and performance of a bioremediation strategy. The aim of this paper is to review the bioremediation techniques and strategies using microorganisms for treatment of hydrocarbon-contaminated Arctic soils. It takes account of Arctic operational conditions and discusses the factors influencing the performance of a bioremediation treatment plan. Preliminary hazard analysis is used as a technique to identify and assess the hazards that threaten the reliability and maintainability of a bioremediation treatment technology. Some key parameters with regard to the feasibility of the suggested preventive/corrective measures are described as well. PMID:24903252

Naseri, Masoud; Barabadi, Abbas; Barabady, Javad

2014-10-01

394

Chromium and arsenic in contaminated soils (Review of publications)  

NASA Astrophysics Data System (ADS)

In the last decades, the chromium clarke in the world’s soils has been revised and reduced; at present, it is equal to 70 mg/kg. No maximal permissible concentration is accepted for the total chromium content in the soils of Russia; it appears reasonable to use the Western European and North American standards in Russia and to take the average value of the maximal permissible concentration equal to 200 mg Cr/kg. Chromium toxicity depends on its oxidizing status. The hazardous effect decreases with the reduction of Cr(VI) to Cr(III). There are various chemical reducers of Cr(VI), including sulfides, dissolved organic substance, aqueous Fe(II) and minerals enriched in Fe(II), and Fe(0). As-containing ore tailings represent a powerful source of technogenic arsenic. Significant environment contamination with natural As is registered in a number of Asian countries. The maximal permissible concentration of total arsenic is equal to 2 mg/kg in Russian soils; it is probably underestimated, because it is lower than the As clarke in soil (5 mg/kg). The approximately permissible concentration (APC) values for As look more reasonable. Arsenic toxicity depends on its oxidation degree: As(III) is 2-3 times more toxic than As(V).

Vodyanitskii, Yu. N.

2009-05-01

395

Bioremediation of coal contaminated soil under sulfate-reducing condition.  

PubMed

The objective of this study was to investigate the biodegradation of coal-derived hydrocarbons, especially high molecular weight (HMW) components, under anaerobic conditions. For this purpose biodegradation experiments were performed, using specifically designed soil column bioreactors. For the experiment, coal-contaminated soil was prepared, which contains high molecular weight hydrocarbons at high concentration (approx. 55.5 mgC g-drysoil(-1)). The experiment was carried out in two different conditions: sulfate reducing (SR) condition (SO4(2-) = 10 mmol l(-1) in the liquid medium) and control condition (SO4(2-)<0.5 mmol l(-1)). Although no degradation was observed under the control condition, the resin fraction decreased to half (from 6,541 to 3,386 mgC g-soil(-1)) under SR condition, with the concomitant increase of two PAHs (phenanthrene and fluoranthene, 9 and 2.5 times, respectively). From these results, we could conclude that high molecular hydrocarbons were biodegradable and transformed to low molecular weight PAHs under the sulfate-reducing condition. Since these PAHs are known to be biologically degraded under aerobic condition, a serial combination of anaerobic (sulfate reducing) and then aerobic bioremediations could be effective and useful for the soil pollution by petroleum and/or coal derived hydrocarbons. PMID:16457179

Kuwano, Y; Shimizu, Y

2006-01-01

396

Contamination of soil, soil gas, and ground water by hydrocarbon compounds near Greear, Morgan County, Kentucky. Water resources investigation  

Microsoft Academic Search

The purpose of the report is to present the results of an investigation of hydrocarbon contamination near Greear, KY. Specifically, the report describes the areal extent and migration of the hydrocarbon contamination in the soil, soil gas, and ground water in the study area. The report also includes a description of the hydrogeologic framework of the Greear area. The application

A. G. Alexander; D. D. Zettwoch; M. D. Unthank; R. B. Burns

1993-01-01

397

Soil and Water Science Department University of Florida Field demonstration of metal immobilization in contaminated soils using p  

E-print Network

in contaminated soils using p amendments Ma, L. Q., W. Harris, and P. Nkedi-Kizza 4/1998-3/2001 Metal of using P amendments to treat metal-contaminated soils in the field by reducing their solubility two will be devoted to field application of P amendments (mixture of phosphate rock and P fertilizer

Ma, Lena

398

Artificial radioactivity in environmental media (air, rainwater, soil, vegetation) in Austria after the Fukushima nuclear accident.  

PubMed

Several environmental media in Austria were monitored for artificial radionuclides released during the Fukushima nuclear accident. Air (up to 1.2 mBq/m(3) particulate (131)I) and rainwater (up to 5.2 Bq/L (131)I) proved to be the media best suited for the environmental monitoring, allowing also a temporal resolution of the activity levels. Significant regional differences in the wet deposition of (131)I with rain could be observed within the city of Vienna during the arrival of the contaminated air masses. Forward-trajectory analysis supported the hypothesis that the contaminated air masses coming from the northwest changed direction to northeast over Northern Austria, leading to a strong activity concentration gradient over Vienna. In the course of the environmental monitoring of the Fukushima releases, this phenomenon-significant differences of (131)I activity concentrations in rainwater on a narrow local scale (8.1 km)-appears to be unique. Vegetation (grass) was contaminated with (131)I and/or (137)Cs at a low level. Soil (up to 22 Bq/kg (137)Cs) was only affected by previous releases (nuclear weapon tests, Chernobyl). Here, also significant local differences can be observed due to different deposition rates during the Chernobyl accident. The effective ecological half-lives of (137)Cs in soil were calculated for four locations in Austria. They range from 7 to 30 years. No Austrian sample investigated herein exceeded the detection limit for (134)Cs; hence, the Fukushima nuclear accident did not contribute significantly to the total radiocesium inventory in Austrian environmental media. The levels of detected radioactivity were of no concern for public health. PMID:22961486

Steinhauser, Georg; Merz, Stefan; Hainz, Dieter; Sterba, Johannes H

2013-04-01

399

Sparingly-Soluble Phosphate Rock Induced Significant Plant Growth and Arsenic Uptake by Pteris vittata from Three Contaminated Soils  

E-print Network

vittata from Three Contaminated Soils Jason T. Lessl and Lena Q. Ma,, * Soil and Water Science Department fertilizer (P-soil). During the 2.5-year, PV obtained sufficient P (1882 vs 2225 mg kg-1 ) from PR-soils-contaminated soils over five harvests in 2.5 years in raised beds (162 kg soil/bed). We tested the hypothesis

Ma, Lena

400

Remediation aspect of microbial changes of plant rhizosphere in mercury contaminated soil  

Microsoft Academic Search

Phytoremediation, an approach that uses plants to remediate contaminated soil through degradation, stabilization or accumulation,\\u000a may provide an efficient solution to some mercury contamination problems. This paper presents growth chamber experiments that\\u000a tested the ability of plant species to stabilize mercury in soil. Several indigenous herbaceous species and Salix viminalis were grown in soil collected from a mercury-contaminated site in

Aleksandra Sas-Nowosielska; Regina Galimska-Stypa; Rafa? Kucharski; Urszula Zielonka; Eugeniusz Ma?kowski; Laymon Gray

2008-01-01

401

Survey on radioactive contamination in Beijing following the Japanese Fukushima nuclear accident.  

PubMed

The radioactive contamination in Beijing caused by the Japanese Fukushima nuclear accident was monitored. In this research, samples of air, rainwater, surface water and vegetables in Beijing were collected and measured to estimate the radioactive contamination levels in Beijing. During the period from the 15th to the 41st day after the first emission of radioactive material (first emission) from the Japanese Fukushima nuclear power station (NPS) on 12 March 2011, obvious radioactive contamination was found in the Beijing air samples. The maximum concentration of I-131 was 5.89 mBq m(-3) in the air samples detected on the 22nd day after the first emission, and the maximum concentration of Cs-137 and Cs-134 was found on the 20th day after the first emission. Except for one sample of rainwater, no artificial radionuclides associated with Fukushima were found in surface water. The measurement results showed that there was no harm to the health of local Beijing residents. PMID:23803226

Lou, Yun; Wan, Ling; Ma, Yongzhong; Li, Huijuan; Meng, Qinghua; Kong, Yuxia; Zhu, Weijie; Wu, Dapeng; Cui, Limeng

2013-09-01

402

Mixing of an anthracene-contaminated soil: a simple but efficient remediation technique?  

PubMed

Contamination of soils with polycyclic aromatic hydrocarbons (PAHs) is a serious problem in petroleum producing countries, such as México, and environment-friendly easy to apply techniques are required to accelerate the removal of the contaminants. Removal of anthracene was monitored in an arable and a pasture soil regularly mixed or amended with organic material, a non-ionic surfactant (Surfynol(®) 485) or earthworms (Eisenia fetida (Savigny, 1826)). In both soils the same results were obtained although the removal of anthracene was faster from the pasture than from the arable soil. The fastest removal of anthracene was obtained when the soil was mixed every 7 days and no contaminant was detected in both soils after 56 days. The second fastest removal of anthracene was obtained when earthworms were added to soil and no contaminant was detected in both soils after 112 days. Application of organic material that served as feed for the earthworms also accelerated the removal of the contaminant compared to the unamended soil, but application of the surfactant inhibited the dissipation of the contaminant. Only 37% of the spiked anthracene was removed from soil when surfactant was applied, while 62% was dissipated in the unamended soil after 112 days. It was found that simply mixing a soil removed anthracene faster than when earthworms were applied, while the application of the surfactant inhibited the removal of anthracene by the autochthonous soil microorganisms. PMID:23896178

Delgado-Balbuena, Laura; Aguilar-Chávez, Ángel R; Luna-Guido, Marco L; Dendooven, Luc

2013-10-01

403

Analytical mass leaching model for contaminated soil and soil stabilized waste  

SciTech Connect

An analytical model for evaluating mass leaching from contaminated soil or soil stabilized waste is presented. The model is based on mass transport due to advection, dispersion, and retardation and can be used to evaluate the suitability and/or efficiency of soil washing solutions based on the results of column leaching studies. The model differs from more traditional models for column leaching studies in that the analysis is based on the cumulative mass of leachate instead of leachate concentration. A cumulative mass basis for leaching eliminates the requirement for determination of instantaneous effluent concentrations in the more traditional column leaching approach thereby allowing for the collection of relatively large effluent volumes. The cumulative masses of three heavy metals -- Cd, Pb, and Zn -- leached from two specimens of soil mixed with fly ash are analyzed with the mass leaching model to illustrate application and limitation of the model.

Shackelford, C.D. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Civil Engineering; Glade, M.J. [Parsons Engineering Science, Inc., Denver, CO (United States)

1997-03-01

404

Relative Bioavailability and Bioaccessability and Speciation of Arsenic in Contaminated Soils  

EPA Science Inventory

Background: Assessment of soil arsenic (As) bioavailability may profoundly affect the extent of remediation required at contaminated sites by improving human exposure estimates. Because small adjustments in soil As bioavailability estimates can significantly alter risk assessment...

405

Phytoremediation offers an ecologically and economically attractive remediation technique for soils contaminated with  

E-print Network

1439 Phytoremediation offers an ecologically and economically attractive remediation technique for soils contaminated with polycyclic aromatic hydrocarbons (PAHs). In addition to the choice of plant turnover, which has been associated with increases in soil microbial populations. To assess the influence

406

The atmospheric release of benzene, toluene, ethylbenzene, and xylene from contaminated soils  

E-print Network

for the remediation of gasoline contaminated soils. Excavation and removal of soils containing hydrocarbons is the most widely used remediation technique because of immediate and total site cleanup. Benzene, toluene, ethylbenzene, and xylene (BTEX) combined are from...

Ramsey, Ronald Roland

2012-06-07

407

In situ phytoextraction of polychlorinated biphenyl - (PCB)contaminated soil.  

PubMed

A pilot-scale field trial of phytoextraction of PCBs provides insight into the practical application of this technology, using the plant species Cucurbita pepo ssp pepo cv. Howden (pumpkin), Carex normalis (sedge), and Festuca arundinacea (tall fescue). This in situ trial took place at a historically contaminated field site, in soil contaminated with a mean concentration of 46 microg/g (range of 0.6 - 200 microg/g) total PCBs (Aroclor 1254/1260). Shoot bioaccumulation factors (where BAF(shoot)=[PCB(shoot)]/[PCB(soil)]) of up to 0.29 were achieved in sedge. Pumpkin plants produced shoot BAFs of only 0.15. However, PCB concentrations in pumpkin shoots decreased as the distance above the root increased, suggesting that higher overall pumpkin shoot BAFs might be achieved in shorter, more densely planted plants. A model for estimating the overall PCB concentration in large pumpkin shoots with minimal sampling is proposed. Examination of congener data supports the hypothesis that C. pepo ssp pepo plants exhibit a unique biological uptake mechanism that allows for the accumulation of a significant concentration of PCBs in plant shoots. Although this mechanism is not well understood, the co-eluting IUPAC congeners 93/95 and 105/127 appear to be preferentially mobilized. Presently, all three plant species exhibit potential as PCB phytoextractors, however further research is required to elucidate methods for optimizing this technology. PMID:17258285

Whitfield Aslund, Melissa L; Zeeb, Barbara A; Rutter, Allison; Reimer, Kenneth J

2007-03-01

408

Integrated management of radioactive strontium contamination in aqueous stream systems.  

PubMed

A combination of biomass treatment, fluidized bed/membrane reactor, and a minimum-suspension fluidized bed reactor is proposed to remove strontium cations from aqueous solutions, such as those generated by nuclear reactors. After conducting a series of screening tests, three adsorbents were selected for their suitability and high adsorptive capacity. The proposed combination uses Chlorella vulgaris in a packed column, followed by the fluidized bed/membrane reactor with bentonite powder in suspension. The membrane is primarily used to retain bentonite powder in the reactor. However, the same can be designed to remove additional amount of contaminant from the aqueous stream. The final separation is carried out in a fluidized bed containing resins that are suspended with minimal airflow. In laboratory scale, a flow rate of 600 ml/h was achieved for 30 min during which period the inlet concentration of 100 mg/l was reduced to 2.5 mg/l at the outlet. Bio-encapsulation with thermophilic bacteria and subsequent separation is proposed at this point in order to reduce the concentration to an even lower level. The proposed separation scheme offers an acceptable solution to removing strontium while minimizing the generation of secondary waste. PMID:11381458

Chaalal, O; Islam, M R

2001-01-01

409

Remote identification of radioactive contamination by satellite measurements  

NASA Astrophysics Data System (ADS)

The simultaneous measurements of the magnetic and electric component of ELF/VLF emission field, low-energy electrons and ambient satellite plasma temperature by ``Intercosmos 19'' satellite data are analyzed. It is established, that in the Barents-Kara Sea region the areas of the observation of simultaneous fluctuations of these parameters have coincided with zones of high contents of cesium (137Cs) at bottom sediments. The observation results in conjunction with ionospheric anomalies observed by the Japan ISS-b satellite instruments, that was active above Barents-Kara shelf region also, were analyzed (analysed). We prepare the maps of the hydrogen, helium and oxygen ions distribution above South Barents hollow by using the data of Japan satellite. It is established, that the area of registration of light ions by Japan satellite ISS-b has coincided with the area of the observation of simultaneous small-scale fluctuations of plasma parameters by Intercosmos 19 satellite data. On the basis of the all the method of detection of radiological contamination in the near-ground atmosphere layer, in the bottom sediment and in the water layer is offered. The method includes simultaneous measurement of parameters of near-earth plasma: magnetic and electrical component of ELF/VLF emission field, of low-energy electrons, of ambient satellite plasma temperature and intensity of light ions. Received results of our investigation can be utilised for forecasting in an ecology, seismology, in geology of oil and hydrogeology.

Larkina, V. I.; Ruzhin, Yu. Ya.; Sergeeva, N. G.; Senin, B. V.

410

Toxicity of naturally-contaminated manganese soil to selected crops.  

PubMed

The impact of manganese excess using naturally contaminated soil (Mn-soil, pseudototal Mn 6494 vs 675 ?g g(-1) DW in control soil) in the shoots of four crops was studied. Mn content decreased in the order Brassica napus > Hordeum vulgare > Zea mays > Triticum aestivum. Growth was strongly depressed just in Brassica (containing 13696 ?g Mn g(-1) DW). Some essential metals (Zn, Fe) increased in Mn-cultured Brassica and Zea, while macronutrients (K, Ca, Mg) decreased in almost all species. Toxic metals (Ni and Cd) were rather elevated in Mn-soil. Microscopy of ROS, NO, lipid peroxidation, and thiols revealed stimulation in all Mn-cultured crops, but changes were less visible in Triticum, a species with low shoot Mn (2363 ?g g(-1) DW). Antioxidative enzyme activities were typically enhanced in Mn-cultured plants. Soluble phenols increased in Brassica only while proteins rather decreased in response to Mn excess. Inorganic anions (chloride, sulfate, and phosphate) were less accumulated in almost all Mn-cultured crops, while the nitrate level rather increased. Organic anions (malate, citrate, oxalate, acetate, and formate) decreased or remained unaffected in response to Mn-soil culture in Brassica, Hordeum, and Triticum but not in Zea. However, the role of organic acids in Mn uptake in these species is not assumed. Because control and Mn-soil differed in pH (6.5 and 3.7), we further studied its impact on Mn uptake in solution culture (using Mn concentration ?5 mM deducted from water-soluble fraction of Mn-soil). Shoot Mn contents in Mn-treated plants were similar to those observed in soil culture (high in Brassica and low in Triticum) and pH had negligible impact. Fluorescence indicator of "general ROS" revealed no extensive or pH-dependent impact either in control or Mn-cultured roots. Observed toxicity of Mn excess to common crops urges for selection of cultivars with higher tolerance. PMID:24965550

Ková?ik, Jozef; Št?rbová, Dagmar; Babula, Petr; Švec, Pavel; Hedbavny, Josef

2014-07-23

411

Bioreduction of uranium in a contaminated soil column.  

PubMed

The bioreduction of soluble uranium [U(VI)] to sparingly soluble U(IV) species is an attractive remedial technology for contaminated soil and groundwater due to the potential for immobilizing uranium and impeding its migration in subsurface environments. This manuscript describes a column study designed to simulate a three-step strategy proposed for the remediation of a heavily contaminated site at the U.S. Department of Energy's NABIR Field Research Center in Oak Ridge, TN. The soil is contaminated with high concentrations of uranium, aluminum, and nitrate and has a low, highly buffered pH (approximately 3.5). Steps proposed for remediation are (i) flushing to remove nitrate and aluminum, (ii) neutralization to establish pH conditions favorable for biostimulation, and (iii) biostimulation for U(VI) reduction. We simulated this sequence using a packed soil column containing undisturbed aggregates of U(VI)-contaminated saprolite that was flushed with an acidified salt solution (pH 4.0), neutralized with bicarbonate (60 mM), and then biostimulated by adding ethanol. The column was operated anaerobically in a closed-loop recirculation setup. However, during the initial month of biostimulation, ethanol was not utilized, and U(VI) was not reduced. A bacterial culture enriched from the site groundwaterwas subsequently added, and the consumption of ethanol coupled with sulfate reduction immediately ensued. The aqueous concentration of U(VI) initially increased, evidently because of the biological production of carbonate, a ligand known to solubilize uranyl. After approximately 50 days, aqueous U(VI) concentrations rapidly decreased from approximately 17 to <1 mg/L. At the conclusion of the experiment,the presence of reduced solid phase U(IV) was confirmed using X-ray absorption near edge structure spectroscopy. The results indicate that bioreduction to immobilize uranium is potentially feasible at this site; however, the stability of the reduced U(IV) and its potential reoxidation will require further investigation, as do the effects of groundwater chemistry and competitive microbial processes, such as methanogenesis. PMID:16053082

Gu, Baohua; Wu, Wei-Min; Ginder-Vogel, Matthew A; Yan, Hui; Fields, Matthew W; Zhou, Jizhong; Fendorf, Scott; Criddle, Craig S; Jardine, Philip M

2005-07-01

412

Development of melt refining decontamination technology for low level radioactive metal waste contaminated with uranium  

NASA Astrophysics Data System (ADS)

The feasibility study of Melt Refining Decontamination by Slagging (MRDS) havs been performed for the release and recycling of Low Level Radioactive Metal Waste (LLRMW) contaminated with uranium discharged from nuclear fuel cycle facilities. Experiments and their evaluation have been performed for the decontamination performance of the waste containing aluminum and have clarified the followings. Simulated waste was decontaminated to 0.01 Bq/g when the addition of aluminum is below 1.5 wt% in laboratory scale test equipment. This was demonstrated also in the engineering scale experiment for MRDS. These results demonstrate that the MRDS is an effective processing technology for low level radioactive metal waste with uranium.

Aoyama, M.; Miyamoto, Y.; Fukumoto, M.; Suto, O.

2005-02-01

413

Diversity of chromium-resistant bacteria isolated from soils contaminated with dichromate  

Microsoft Academic Search

Intensive industrial applications of hexavalent chromium [Cr(VI)] have caused substantial soil contamination. Chromium-resistant bacteria (CRB) isolated from soils can be used to transform toxic Cr(VI) to less toxic Cr(III) in soils. The objective of this study was to assess the biodiversity of CRB isolated from soils contaminated with potassium dichromate and evaluate the community response to Cr(VI) toxicity. We isolated

Flávio A. O. Camargo; Benedict C. Okeke; Fatima M. Bento; William T. Frankenberger

2005-01-01

414

Organic Amendments to Enhance Atrazine and Metamitron Degradation in Two Contaminated Soils with Contrasting Textures  

Microsoft Academic Search

Among all types of xenobiotics, pesticides such as herbicides play a significant role in soil and water pollution due to their wide usage all over the world. This study addresses the ability of organic amendments to enhance atrazine and metamitron degradation in two herbicide-contaminated soils with contrasting textures under laboratory conditions. Soil samples were collected from surface soils with textures

Mohsen Forouzangohar; Gholam Hosain Haghnia; Alireza Koocheki

2005-01-01

415

Effects of incubation on solubility and mobility of trace metals in two contaminated soils  

E-print Network

.8) of Tampa soil, Montreal soil had an alkaline pH of 7.7 and high Ca of 1.6%. Concentrations of FeEffects of incubation on solubility and mobility of trace metals in two contaminated soils Lena Q. Ma*, Yan Dong Soil and Water Science Department, University of Florida, Gainesville, FL 32611

Ma, Lena

416

Bacterial acquisition of hexachlorobenzene-derived carbon in contaminated soil.  

PubMed

Pesticides are a class of xenobiotics intentionally released into the environment. Hexachlorobenzene (HCB) was used as a fungicide from 1945, leaving behind many contaminated sites. Very few studies have examined the biodegradation of HCB or the fate of HCB-derived carbon. Here we report that certain bacterial populations are capable of deriving carbon from HCB in contaminated soil under aerobic conditions. These populations are primarily Proteobacteria, including Methylobacterium and Pseudomonas, which predominated as detected by stable isotope probing (SIP) and 16S rRNA gene amplicon pyrosequencing. Due to the nature of SIP, which can be used as a functional method solely for assimilatory processes, it is not possible to elucidate whether these populations metabolized directly HCB or intermediates of its metabolism produced by different populations. The possibility exists that HCB is degraded via the formation of pentachlorophenol (PCP), which is further mineralized. With this in mind, we designed primers to amplify PCP 4-monooxygenase-coding sequences based on the available pcpB gene sequence from Methylobacterium radiotolerans JCM 2831. Based on 16S rRNA gene analysis, organisms closely related to this strain were detected in (13)C-labeled DNA. Using the designed primers, we were able to amplify pcpB genes in both total community DNA and (13)C-DNA. This indicates that HCB might be transformed into PCP before it gets assimilated. In summary, this study is the first report on which bacterial populations benefit from carbon originating in the pesticide HCB in a contaminated soil. PMID:25065801

Uhlik, Ondrej; Strejcek, Michal; Vondracek, Jan; Musilova, Lucie; Ridl, Jakub; Lovecka, Petra; Macek, Tomas

2014-10-01

417

An approach to detecting delayed effects of radioactive contamination on industrial-urban-area dwellers.  

PubMed Central

Detecting changes in humans that result from radioactive contamination of the area of residence