AN EVALUATION OF HANFORD SITE TANK FARM SUBSURFACE CONTAMINATION FY2007

Energy Technology Data Exchange (ETDEWEB)

MANN, F.M.

2007-07-10

The Tank Farm Vadose Zone (TFVZ) Project conducts activities to characterize and analyze the long-term environmental and human health impacts from tank waste releases to the vadose zone. The project also implements interim measures to mitigate impacts, and plans the remediation of waste releases from tank farms and associated facilities. The scope of this document is to report data needs that are important to estimating long-term human health and environmental risks. The scope does not include technologies needed to remediate contaminated soils and facilities, technologies needed to close tank farms, or management and regulatory decisions that will impact remediation and closure. This document is an update of ''A Summary and Evaluation of Hanford Site Tank Farm Subsurface Contamination''. That 1998 document summarized knowledge of subsurface contamination beneath the tank farms at the time. It included a preliminary conceptual model for migration of tank wastes through the vadose zone and an assessment of data and analysis gaps needed to update the conceptual model. This document provides a status of the data and analysis gaps previously defined and discussion of the gaps and needs that currently exist to support the stated mission of the TFVZ Project. The first data-gaps document provided the basis for TFVZ Project activities over the previous eight years. Fourteen of the nineteen knowledge gaps identified in the previous document have been investigated to the point that the project defines the current status as acceptable. In the process of filling these gaps, significant accomplishments were made in field work and characterization, laboratory investigations, modeling, and implementation of interim measures. The current data gaps are organized in groups that reflect Components of the tank farm vadose zone conceptual model: inventory, release, recharge, geohydrology, geochemistry, and modeling. The inventory and release components address

AN EVALUATION OF HANFORD SITE TANK FARM SUBSURFACE CONTAMINATION FY 2007

International Nuclear Information System (INIS)

MANN, F.M.

2007-01-01

The Tank Farm Vadose Zone (TFVZ) Project conducts activities to characterize and analyze the long-term environmental and human health impacts from tank waste releases to the vadose zone. The project also implements interim measures to mitigate impacts, and plans the remediation of waste releases from tank farms and associated facilities. The scope of this document is to report data needs that are important to estimating long-term human health and environmental risks. The scope does not include technologies needed to remediate contaminated soils and facilities, technologies needed to close tank farms, or management and regulatory decisions that will impact remediation and closure. This document is an update of ''A Summary and Evaluation of Hanford Site Tank Farm Subsurface Contamination''. That 1998 document summarized knowledge of subsurface contamination beneath the tank farms at the time. It included a preliminary conceptual model for migration of tank wastes through the vadose zone and an assessment of data and analysis gaps needed to update the conceptual model. This document provides a status of the data and analysis gaps previously defined and discussion of the gaps and needs that currently exist to support the stated mission of the TFVZ Project. The first data-gaps document provided the basis for TFVZ Project activities over the previous eight years. Fourteen of the nineteen knowledge gaps identified in the previous document have been investigated to the point that the project defines the current status as acceptable. In the process of filling these gaps, significant accomplishments were made in field work and characterization, laboratory investigations, modeling, and implementation of interim measures. The current data gaps are organized in groups that reflect Components of the tank farm vadose zone conceptual model: inventory, release, recharge, geohydrology, geochemistry, and modeling. The inventory and release components address residual wastes that will

Assessing the hydrocarbon degrading potential of indigenous bacteria isolated from crude oil tank bottom sludge and hydrocarbon-contaminated soil of Azzawiya oil refinery, Libya.

Science.gov (United States)

Mansur, Abdulatif A; Adetutu, Eric M; Kadali, Krishna K; Morrison, Paul D; Nurulita, Yuana; Ball, Andrew S

2014-09-01

The disposal of hazardous crude oil tank bottom sludge (COTBS) represents a significant waste management burden for South Mediterranean countries. Currently, the application of biological systems (bioremediation) for the treatment of COTBS is not widely practiced in these countries. Therefore, this study aims to develop the potential for bioremediation in this region through assessment of the abilities of indigenous hydrocarbonoclastic microorganisms from Libyan Hamada COTBS for the biotreatment of Libyan COTBS-contaminated environments. Bacteria were isolated from COTBS, COTBS-contaminated soil, treated COTBS-contaminated soil, and uncontaminated soil using Bushnell Hass medium amended with Hamada crude oil (1 %) as the main carbon source. Overall, 49 bacterial phenotypes were detected, and their individual abilities to degrade Hamada crude and selected COBTS fractions (naphthalene, phenanthrene, eicosane, octadecane and hexane) were evaluated using MT2 Biolog plates. Analyses using average well colour development showed that ~90 % of bacterial isolates were capable of utilizing representative aromatic fractions compared to 51 % utilization of representative aliphatics. Interestingly, more hydrocarbonoclastic isolates were obtained from treated contaminated soils (42.9 %) than from COTBS (26.5 %) or COTBS-contaminated (30.6 %) and control (0 %) soils. Hierarchical cluster analysis (HCA) separated the isolates into two clusters with microorganisms in cluster 2 being 1.7- to 5-fold better at hydrocarbon degradation than those in cluster 1. Cluster 2 isolates belonged to the putative hydrocarbon-degrading genera; Pseudomonas, Bacillus, Arthrobacter and Brevundimonas with 57 % of these isolates being obtained from treated COTBS-contaminated soil. Overall, this study demonstrates that the potential for PAH degradation exists for the bioremediation of Hamada COTBS-contaminated environments in Libya. This represents the first report on the isolation of

Bioremediation of PAH contaminated soil samples

International Nuclear Information System (INIS)

Joshi, M.M.; Lee, S.

1994-01-01

Soils contaminated with polynuclear aromatic hydrocarbons (PAHs) pose a hazard to life. The remediation of such sites can be done using physical, chemical, and biological treatment methods or a combination of them. It is of interest to study the decontamination of soil using bioremediation. The experiments were conducted using Acinetobacter (ATCC 31012) at room temperature without pH or temperature control. In the first series of experiments, contaminated soil samples obtained from Alberta Research Council were analyzed to determine the toxic contaminant and their composition in the soil. These samples were then treated using aerobic fermentation and removal efficiency for each contaminant was determined. In the second series of experiments, a single contaminant was used to prepare a synthetic soil sample. This sample of known composition was then treated using aerobic fermentation in continuously stirred flasks. In one set of flasks, contaminant was the only carbon source and in the other set, starch was an additional carbon source. In the third series of experiments, the synthetic contaminated soil sample was treated in continuously stirred flasks in the first set and in fixed bed in the second set and the removal efficiencies were compared. The removal efficiencies obtained indicated the extent of biodegradation for various contaminants, the effect of additional carbon source, and performance in fixed bed without external aeration

Regional hydrocarbon contaminated soil recycling facility standards

International Nuclear Information System (INIS)

Warren, R.

1992-01-01

In an effort to protect the environment from uncontrolled releases of petroleum products, the Canadian Petroleum Products Institute member companies have initiated environmental upgrading programs for their underground fuel storage systems in British Columbia. These programs have been restricted in recent years as a result of environmental regulations targeting contaminated soil, which is generated when underground storage tanks are upgraded to current standards. The soil requiring treatment is typically sand backfill containing a nominal value of petroleum product. These soils can be treated in an engineered basin using bioremediation technology to reduce the level of contamination. Depending on the degree of treatment, the soil can be recycled as backfill or reused as landfill cover. An overview is presented of the basin treatment process and design. Natural bioremediation is enhanced with nutrients, water and oxygen addition. 4 figs

Application of Ultrasonic for Decontamination of Contaminated Soil - 13142

International Nuclear Information System (INIS)

Vasilyev, A.P.; Lebedev, N.M.; Savkin, A.E.

2013-01-01

The trials of soil decontamination were carried out with the help of a pilot ultrasonic installation in different modes. The installation included a decontamination bath equipped with ultrasonic sources, a precipitator for solution purification from small particles (less than 80 micrometer), sorption filter for solution purification from radionuclides washing out from soil, a tank for decontamination solution, a pump for decontamination solution supply. The trials were carried out on artificially contaminated sand with specific activity of 4.5 10 5 Bk/kg and really contaminated soil from Russian Scientific Center 'Kurchatovsky Institute' (RSC'KI') with specific activity of 2.9 10 4 Bk/kg. It was established that application of ultrasonic intensify the process of soil reagent decontamination and increase its efficiency. The decontamination factor for the artificially contaminated soil was ∼200 and for soil from RSC'KI' ∼30. The flow-sheet diagram has been developed for the new installation as well as determined the main technological characteristics of the equipment. (authors)

Soil contamination standards for protection of personnel

International Nuclear Information System (INIS)

Rittmann, P.D.

1998-01-01

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

Soil contamination standards for protection of personnel

Energy Technology Data Exchange (ETDEWEB)

Rittmann, P.D.

1998-04-16

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.

POTENTIAL REUSE OF PETROLEUM-CONTAMINATED SOIL: A DIRECTORY OF PERMITTED RECYCLING FACILITIES

Science.gov (United States)

Soil contaminated by virgin petroleum products leaking from underground storage tanks Is a pervasive problem in the United States. Economically feasible disposal of such soil concerns the responsible party (RP), whether the RP is one individual small business owner, a group o...

Separation of the Shuttle Columbia's external fuel tank

Science.gov (United States)

1981-01-01

Separation of the Shuttle Columbia's external fuel tank (ET), photographed by a camera in the umbilical bay. Camera was able to record the underside of the tank as the orbiter toward its earth-orbital mission and the fuel tank fell toward the earth.

Bioremediation of diesel contamination at an underground storage tank site: a spatial analysis of the microbial community.

Science.gov (United States)

Andreolli, Marco; Albertarelli, Nicola; Lampis, Silvia; Brignoli, Pierlorenzo; Khoei, Nazaninalsadat Seyed; Vallini, Giovanni

2016-01-01

The present study reports on a real case of contamination due to the chronic leakage of diesel fuel from an underground tank at a dismissed service station. Speciation of the microbial community according to both lateral and vertical gradients from the origin of the contaminant release was analyzed by means of the PCR-DGGE technique. Moreover, the effects of a landfarming treatment on both the microbial community structure and the abatement of contamination were analyzed. The concentration of total petrol hydrocarbons (TPHs) decreased along the horizontal gradient (from 7042.2 ± 521.9 to 112.2 ± 24.3 mg kg(-1)), while increased downwards from the position of the tank (from 502.6 ± 43.7 to 4972.5 ± 275.3 mg kg(-1)). PCR-DGGE analyses and further statistical treatment of the data indicated a correlation between structure of the bacterial communities and amount of diesel fuel contamination. On the other hand, level of contamination, soil texture and depth were shown to affect the fungal community. Chloroflexi and Ascomycota were the most abundant microbes ascertained through culture-independent procedures. Landfarming promoted 91.6 % reduction of TPHs in 75 days. Furthermore, PCR-DGGE analyses evidenced that both bacterial and fungal communities of the treated soil were restored to the pristine conditions of uncontaminated topsoil. The present study demonstrated that bacterial and fungal communities were affected differently by soil factors such as level of hydrocarbon contamination as well as soil depth and texture. This report shows that a well-planned landfarming treatment can drive the restoration of the soil in terms of both abatement of the contaminants and resilience of the microbial community structure.

Application of Ultrasonic for Decontamination of Contaminated Soil - 13142

Energy Technology Data Exchange (ETDEWEB)

Vasilyev, A.P. [JRC ' NIKIET' , Moscow (Russian Federation); Lebedev, N.M. [LLC ' Aleksandra-Plus' , Vologda (Russian Federation); Savkin, A.E. [SUE SIA ' Radon' , Moscow (Russian Federation)

2013-07-01

The trials of soil decontamination were carried out with the help of a pilot ultrasonic installation in different modes. The installation included a decontamination bath equipped with ultrasonic sources, a precipitator for solution purification from small particles (less than 80 micrometer), sorption filter for solution purification from radionuclides washing out from soil, a tank for decontamination solution, a pump for decontamination solution supply. The trials were carried out on artificially contaminated sand with specific activity of 4.5 10{sup 5} Bk/kg and really contaminated soil from Russian Scientific Center 'Kurchatovsky Institute' (RSC'KI') with specific activity of 2.9 10{sup 4} Bk/kg. It was established that application of ultrasonic intensify the process of soil reagent decontamination and increase its efficiency. The decontamination factor for the artificially contaminated soil was ∼200 and for soil from RSC'KI' ∼30. The flow-sheet diagram has been developed for the new installation as well as determined the main technological characteristics of the equipment. (authors)

The assumption of heterogeneous or homogeneous radioactive contamination in soil/sediment: does it matter in terms of the external exposure of fauna?

Science.gov (United States)

Beaugelin-Seiller, K

2014-12-01

The classical approach to environmental radioprotection is based on the assumption of homogeneously contaminated media. However, in soils and sediments there may be a significant variation of radioactivity with depth. The effect of this heterogeneity was investigated by examining the external exposure of various sediment and soil organisms, and determining the resulting dose rates, assuming a realistic combination of locations and radionuclides. The results were dependent on the exposure situation, i.e., the organism, its location, and the quality and quantity of radionuclides. The dose rates ranged over three orders of magnitude. The assumption of homogeneous contamination was not consistently conservative (if associated with a level of radioactivity averaged over the full thickness of soil or sediment that was sampled). Dose assessment for screening purposes requires consideration of the highest activity concentration measured in a soil/sediment that is considered to be homogeneously contaminated. A more refined assessment (e.g., higher tier of a graded approach) should take into consideration a more realistic contamination profile, and apply different dosimetric approaches. Copyright © 2014 Elsevier Ltd. All rights reserved.

The time-dependent effect of the biological component of 137Cs soil contamination

International Nuclear Information System (INIS)

Dederichs, H.; Pillath, J.; Lennartz, R.; Hill, P.; Hille, R.

2004-01-01

In investigations of the long-term development of the population dose in the highly contaminated regions of the Commonwealth of Independence States it was found that the external dose has not decreased as strongly as expected since 1992. Further investigations have shown that, contrary to expectations, no linear correlation can be observed between soil contamination and measured area dose rate. As a contribution towards clarifying these issues, the area dose rate and the soil contamination including the plant fraction were investigated in the Korma district, Belarus. It was found that it is necessary to cover and average over larger areas in order to determine from ground contamination the long-term development of the external dose commitment. This means that for this purpose the introduction of an ''effective'' surface contamination (sum of mineral and organic contamination components) is necessary. The phenomena observed are described in a model, which permits an analytical calculation of the contamination profile in soil taking migration and transfer effects into account. The differences observed between the measured soil contamination and the resulting external doses or the directly measured dose rate can be explained by the proposed model. Moreover, their long-term development can be calculated. The results show that a time decade after the accident the biological part of the ''effective'' soil contamination becomes dominant and cannot be neglected. (orig.)

Treatment and disposal of petroleum contaminated soil (June 1996) : revised May 1998

International Nuclear Information System (INIS)

1998-05-01

Leaking petroleum storage tanks and petroleum contaminated sites can pose significant environmental and public safety hazards. Proper mitigation is required to remove this threat. These guidelines are intended to assist environmental consultants, petroleum service contractors, waste disposal ground operators and petroleum storage tank owners in the management of petroleum contaminated soil (PCS). The procedures that should be used for disposal and treatment of PCS at licensed soil treatment facilities, municipal waste disposal grounds, and at single-use soil treatment sites approved by Manitoba Environment are described. The treatment should control excessive emission of volatile organic compounds to the atmosphere. Losses of petroleum compounds by leaching should also be controlled. The main treatment method at government-approved sites is land farming. Other remedial options include enhanced bioremediation, asphalt incorporation, soil washing, and thermal treatment. Permitting and licensing procedures, guidelines for the design and operations at PCS treatment and disposal sites, procedures for the removal and re-use of treated soil and procedures for the decommissioning of PCS treatment sites are also outlined. A list of other associated regulations and guidelines is included. 2 tabs

Treatment options for tank farms long-length contaminated equipment

International Nuclear Information System (INIS)

Josephson, W.S.

1995-01-01

This study evaluated a variety of treatment and disposal technologies for mixed waste (MW) meeting the following criteria: 1. Single-Shell and Double-Shell Tank System (tank farms) equipment and other debris; 2. length greater than 12 feet; and contaminated with listed MW from the tank farms. This waste stream, commonly referred to as tank farms long-length contaminated equipment (LLCE), poses a unique and costly set of challenges during all phases of the waste management lifecycle

Removal of Pah from clay soil contaminated with diesel oil by bioremediation treatments

International Nuclear Information System (INIS)

Changas-spinelli, A. C. O.; Kato, M. T.; Lima, E. S.; Gavazza, S.

2009-01-01

Diesel oil is one of the most common soil organic pollutants, as a consequence of spilling of storage tank spills and accidental leaks. In Pernambuco State, Northeast part of Brazil, there are several evidences of soil contamination by petroleum derivates due to gas station leaking. (Author)

The assumption of heterogeneous or homogeneous radioactive contamination in soil/sediment: does it matter in terms of the external exposure of fauna?

International Nuclear Information System (INIS)

Beaugelin-Seiller, K.

2014-01-01

The classical approach to environmental radioprotection is based on the assumption of homogeneously contaminated media. However, in soils and sediments there may be a significant variation of radioactivity with depth. The effect of this heterogeneity was investigated by examining the external exposure of various sediment and soil organisms, and determining the resulting dose rates, assuming a realistic combination of locations and radionuclides. The results were dependent on the exposure situation, i.e., the organism, its location, and the quality and quantity of radionuclides. The dose rates ranged over three orders of magnitude. The assumption of homogeneous contamination was not consistently conservative (if associated with a level of radioactivity averaged over the full thickness of soil or sediment that was sampled). Dose assessment for screening purposes requires consideration of the highest activity concentration measured in a soil/sediment that is considered to be homogeneously contaminated. A more refined assessment (e.g., higher tier of a graded approach) should take into consideration a more realistic contamination profile, and apply different dosimetric approaches. - Highlights: • Defining contamination as homogeneous may not be conservative for dose assessment. • The impact of source heterogeneity on dose is closely linked to the exposure scenario. • Dosimetric calculations (method and tool) should differ from screening to higher tiers

Ecological Role of Soils upon Radioactive Contamination

Science.gov (United States)

Tsvetnov, Evgeny; Shcheglov, Alexei; Tsvenova, Olga

2016-04-01

The ecological role of soils upon radioactive contamination is clearly manifested in the system of notions about ecosystems services, i.e., benefits gained by humans from ecosystems and their components, including soils (Millennium Ecosystem Assessment, 2005). For the soils, these services are considered on the basis of soil functions in the biosphere that belong to the protective ecosystem functions within the group of soil functions known under the names of "Buffer and protective biogeocenotic shield" (at the level of particular biogeocenoses) and "Protective shield of the biosphere" (at the global biospheric level) (according to Dobrovol'skii & Nikitin, 2005). With respect to radionuclides, this group includes (1) the depositing function, i.e., the accumulation and long-term sequestration of radioactive substances by the soil after atmospheric fallout; (2) the geochemical function, i.e., the regulation of horizontal and vertical fluxes of radionuclides in the system of geochemically conjugated landscapes and in the soil-groundwater and soil-plant systems; and (3) the dose-forming function that is manifested by the shielding capacity of the soil with respect to the external ionizing radiation (lowering of the dose from external radiation) and by the regulation of the migration of radionuclides in the trophic chain (lowering of the dose from internal radiation). The depositing and geochemical functions of the soils are interrelated, which is seen from quantitative estimates of the dynamics of the fluxes of radionuclides in the considered systems (soil-plant, soil-groundwater, etc.). The downward migration of radionuclides into the lower soil layers proceeds very slowly: for decades, more than 90% of the pool of radionuclides is stored in the topmost 10 cm of the soil profile. In the first 3-5 years after the fallout, the downward migration of radionuclides with infiltrating water flows decreases from several percent to decimals and hundredths of percent from the

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

Science.gov (United States)

Kushner, Len

1992-01-01

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.

Soil load above Hanford waste storage tanks (2 volumes)

International Nuclear Information System (INIS)

Pianka, E.W.

1995-01-01

This document is a compilation of work performed as part of the Dome Load Control Project in 1994. Section 2 contains the calculations of the weight of the soil over the tank dome for each of the 75-feet-diameter waste-storage tanks located at the Hanford Site. The chosen soil specific weight and soil depth measured at the apex of the dome crown are the same as those used in the primary analysis that qualified the design. Section 3 provides reference dimensions for each of the tank farm sites. The reference dimensions spatially orient the tanks and provide an outer diameter for each tank. Section 4 summarizes the available soil surface elevation data. It also provides examples of the calculations performed to establish the present soil elevation estimates. The survey data and other data sources from which the elevation data has been obtained are printed separately in Volume 2 of this Supporting Document. Section 5 contains tables that provide an overall summary of the present status of dome loads. Tables summarizing the load state corresponding to the soil depth and soil specific weight for the original qualification analysis, the gravity load requalification for soil depth and soil specific weight greater than the expected actual values, and a best estimate condition of soil depth and specific weight are presented for the Double-Shell Tanks. For the Single-Shell Tanks, only the original qualification analysis is available; thus, the tabulated results are for this case only. Section 6 provides a brief overview of past analysis and testing results that given an indication of the load capacity of the waste storage tanks that corresponds to a condition approaching ultimate failure of the tank. 31 refs

Nonlinear Analysis of the Space Shuttle Superlightweight External Fuel Tank

Science.gov (United States)

Nemeth, Michael P.; Britt, Vicki O.; Collins, Timothy J.; Starnes, James H., Jr.

1996-01-01

Results of buckling and nonlinear analyses of the Space Shuttle external tank superlightweight liquid-oxygen (LO2) tank are presented. Modeling details and results are presented for two prelaunch loading conditions and for two full-scale structural tests that were conducted on the original external tank. The results illustrate three distinctly different types of nonlinear response for thin-walled shells subjected to combined mechanical and thermal loads. The nonlinear response phenomena consist of bifurcation-type buckling, short-wavelength nonlinear bending, and nonlinear collapse associated with a limit point. For each case, the results show that accurate predictions of non- linear behavior generally require a large-scale, high-fidelity finite-element model. Results are also presented that show that a fluid-filled launch-vehicle shell can be highly sensitive to initial geometric imperfections. In addition, results presented for two full-scale structural tests of the original standard-weight external tank suggest that the finite-element modeling approach used in the present study is sufficient for representing the nonlinear behavior of the superlightweight LO2 tank.

A single launch lunar habitat derived from an NSTS external tank

Science.gov (United States)

King, Charles B.; Butterfield, Ansel J.; Hypes, Warren D.; Nealy, John E.; Simonsen, Lisa C.

1990-01-01

A concept for using a spent External Tank from the National Space Transportation System (Shuttle) to derive a Lunar habitat is described. The concept is that the External Tank is carried into Low-Earth Orbit (LEO) where the oxygen tank-intertank subassembly is separated from the hydrogen tank, berthed to Space Station Freedom and the subassembly outfitted as a 12-person Lunar habitat using extravehicular activity (EVA) and intravehicular activity (IVA). A single launch of the NSTS Orbiter can place the External Tank in LEO, provide orbiter astronauts for disassembly of the External Tank, and transport the required subsystem hardware for outfitting the Lunar habitat. An estimate of the astronauts' EVA and IVA is provided. The liquid oxygen tank-intertank modifications utilize existing structures and openings for human access without compromising the structural integrity of the tank. The modification includes installation of living quarters, instrumentation, and an air lock. Feasibility studies of the following additional systems include micrometeoroid and radiation protection, thermal-control, environmental-control and life-support, and propulsion. The converted Lunar habitat is designed for unmanned transport and autonomous soft landing on the Lunar surface without need for site preparation. Lunar regolith is used to fill the micrometeoroid shield volume for radiation protection using a conveyor. The Lunar habitat concept is considered to be feasible by the year 2000 with the concurrent development of a space transfer vehicle and a Lunar lander for crew changeover and resupply.

Assessment Of Depleted Uranium Contamination In Selective IRAQI Soils

International Nuclear Information System (INIS)

Mohammed, A.A.; Hussien, A.Sh.M.; Tawfiq, N.F.

2008-01-01

The aim of this research was to measure the radiation exposure rates in three selected Locations in southren part of Iraq (two in Nassireya, and one in Amara) resulted from the existence of depleted uranium in soil and metal pieces have been taken from destroyed tank and study mathmatically the concentration of Depleted Uranium by its dispersion from soil surface by winds and rains from 2003 to 2007. The exposure rates were measured using inspector device, while depleted uranium concentration in soil samples and tank's matal pieces were detected with Solid State Nuclear Track Detectors(SSNTDs). The wind and rain effects were considered in the calculation of dispersion effect on depleted uranium concentration in soil, where the wind effect were calculated with respect to the sites nature and soil conditions, and rain effect with respect to dispersive-convective equation for radionuclide in soil. The results obtained for the exposure rates were high near the penetrated surfac, moderate and low in soil and metal pices. The Depleted Uranium concentration in soil and metal pieces have the highest value in Nassireya. The results from dispersion calculation (wind & rain) showed that the depleted uranium concentration in 2008 will be less than the danger level and in allowable contamination range

Preliminary study of radium-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Healy, J.W.; Rodgers, J.C.

1978-10-01

A preliminary study was made of the potential radiation exposures to people from radium-226 contamination in the soil in order to provide guidance on limits to be applied in decontaminating land. Pathways included were inhalation of radium from resuspension; ingestion of radium with foods; external gamma radiation from radium daughters; inhalation of radon and daughter, both in the open air and in houses; and the intake of /sup 210/Pb and /sup 210/Po from both inhalation and ingestion. The depth of the contaminated layer is of importance for external exposure and especially for radon emanation. The most limiting pathway was found to be emanation of the radon into buildings with limiting values comparable to those found naturally in many areas.

Preliminary study of radium-contaminated soils

International Nuclear Information System (INIS)

Healy, J.W.; Rodgers, J.C.

1978-10-01

A preliminary study was made of the potential radiation exposures to people from radium-226 contamination in the soil in order to provide guidance on limits to be applied in decontaminating land. Pathways included were inhalation of radium from resuspension; ingestion of radium with foods; external gamma radiation from radium daughters; inhalation of radon and daughter, both in the open air and in houses; and the intake of 210 Pb and 210 Po from both inhalation and ingestion. The depth of the contaminated layer is of importance for external exposure and especially for radon emanation. The most limiting pathway was found to be emanation of the radon into buildings with limiting values comparable to those found naturally in many areas

Surface gamma-ray survey of SX Tank Farm

International Nuclear Information System (INIS)

Stromswold, D.C.; Arthur, R.J.

1996-08-01

Measurements made over the surface of the SX Tank Farm at Hanford show Cs 137 to be the only significant gamma ray emitting contaminant. A high-purity germanium detector collected the data in the surface survey. Most of the detected radiation originated from specific above ground objects, such as pipes and vents. One area of increased radiation in the north section of the tank farm between tanks SX-102 and SX-105, was apparently due to contamination of the soil by Cs 137. An area of interest near tanks SX-108, SX-111, and SX-112, below which borehole logs has indicated deep Cs 137 contamination, also showed Cs 137 at the surface, but the signal originated mainly from surface objects rather than from contaminated soils. A significant result of the surface survey is the understanding that surface objects with contamination can affect the signal observed by borehole logging tools as they reach the ground surface

Assisted bioremediation tests on three natural soils contaminated with benzene

Directory of Open Access Journals (Sweden)

Maria Manuela Carvalho

2015-07-01

Full Text Available Bioremediation is an attractive and useful method of remediation of soils contaminated with petroleum hydrocarbons because it is simple to maintain, applicable in large areas, is economic and enables an effective destruction of the contaminant. Usually, the autochthone microorganisms have no ability to degrade these compounds, and otherwise, the contaminated sites have inappropriate environmental conditions for microorganism’s development. These problems can be overcome by assisted bioremediation (bioaugmentation and/or biostimulation. In this study the assisted bioremediation capacity on the rehabilitation of three natural sub-soils (granite, limestone and schist contaminated with benzene was evaluated. Two different types of assisted bioremediation were used: without and with ventilation (bioventing. The bioaugmentation was held by inoculating the soil with a consortium of microorganisms collected from the protection area of crude oil storage tanks in a refinery. In unventilated trials, biostimulation was accomplished by the addition of a nutrient mineral media, while in bioventing oxygen was also added. The tests were carried out at controlled temperature of 25 ºC in stainless steel columns where the moist soil contaminated with benzene (200 mg per kg of soil occupied about 40% of the column’s volume. The processes were daily monitored in discontinued mode. Benzene concentration in the gas phase was quantified by gas chromatography (GC-FID, oxygen and carbon dioxide concentrations were monitored by respirometry. The results revealed that the three contaminated soils were remediated using both technologies, nevertheless, the bioventing showed faster rates. With this work it was proved that respirometric analysis is an appropriate instrument for monitoring the biological activity.

Delineation of ground-water contamination using soil-gas analyses near Jackson, Tennessee

Science.gov (United States)

Lee, R.W.

1991-01-01

An investigation of the ground-water resources near Jackson, West Tennessee, was conducted during 1988-89. The study included determination of the occurrence of contaminants in the shallow aquifer using soil-gas analyses in the unsaturated zone. Between 1980 and 1988, an underground fuel-storage tank leaked about 3,000 gallons of unleaded fuel to the water table about 4 feet below land surface. A survey of soil gas using a gas chromatograph equipped with a photoionization detector showed concentrations of volatile organic compounds greater than IO, 000 parts per million near the leak These compounds were detected in an area about 240 feet long and 110 feet wide extending west from the point source. The chromatograms provided two distinct 'fingerprints' of volatile organic compounds. The first revealed the presence of benzene, toluene, andxylenes, which are constituents of unleaded fuel, in addition to other volatile compounds, in soil gas in the area near the leak The second did not reveal any detectable benzene, toluene, or xylenes in the soil-gas samples, but showed the presence of other unidentified volatile organic compounds in soil gas north of the storage tank. The distribution of total concentrations of volatile organic compounds in the unsaturated zone indicated that a second plume about 200 feet long and 90 feet wide was present about 100 feet north of the storage tank The second plume could have been the result of previous activities at this site during the 1950's or earlier. Activities at the site are believed to have included storage of solvents used at the nearby railyard and flushing of tanks containing tar onto a gravel-covered parking area. The delineation of these plumes has shown that soil-gas analyses can be a useful technique for identifying areas of contamination with volatile organic compounds in shallow water-table aquifers and may have broad applications in similar situations where the water table is relatively close to the surface.

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

International Nuclear Information System (INIS)

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

2013-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2013-07-01

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

Nonlinear Analysis of the Space Shuttle Super-Lightweight External Fuel Tank

Science.gov (United States)

Nemeth, Michael P.; Britt, Vicki O.; Collins, Timothy J.; Starnes, James H., Jr.

1996-01-01

The results of buckling and nonlinear analyses of the Space Shuttle External Tank super-lightweight liquid oxygen (LOX) tank are presented. Modeling details and results are presented for two prelaunch loading conditions and for two full-scale structural tests conducted on the original external tank. These results illustrate three distinctly different types of nonlinear responses for thin-walled shells subjected to combined mechanical and thermal loads. These nonlinear response phenomena consist of bifurcation-type buckling, short-wavelength nonlinear bending, and nonlinear collapse associated with a limit point. For each case, the results show that accurate predictions of nonlinear behavior generally require a large scale high-fidelity finite element model. Results are also presented that show that a fluid filled launch vehicle shell can be highly sensitive to initial geometric imperfections. In addition, results presented for two full scale structural tests of the original standard weight external tank suggest that the finite element modeling approach used in the present study is sufficient for representing the nonlinear behavior of the super lightweight LOX tank.

Petroleum hydrocarbon biodegradation under seasonal freeze-thaw soil temperature regimes in contaminated soils from a sub-Arctic site.

Science.gov (United States)

Chang, Wonjae; Klemm, Sara; Beaulieu, Chantale; Hawari, Jalal; Whyte, Lyle; Ghoshal, Subhasis

2011-02-01

Several studies have shown that biostimulation in ex situ systems such as landfarms and biopiles can facilitate remediation of petroleum hydrocarbon contaminated soils at sub-Arctic sites during summers when temperatures are above freezing. In this study, we examine the biodegradation of semivolatile (F2: C10-C16) and nonvolatile (F3: C16-C34) petroleum hydrocarbons and microbial respiration and population dynamics at post- and presummer temperatures ranging from -5 to 14 °C. The studies were conducted in pilot-scale tanks with soils obtained from a historically contaminated sub-Arctic site in Resolution Island (RI), Canada. In aerobic, nutrient-amended, unsaturated soils, the F2 hydrocarbons decreased by 32% during the seasonal freeze-thaw phase where soils were cooled from 2 to -5 °C at a freezing rate of -0.12 °C d(-1) and then thawed from -5 to 4 °C at a thawing rate of +0.16 °C d(-1). In the unamended (control) tank, the F2 fraction only decreased by 14% during the same period. Biodegradation of individual hydrocarbon compounds in the nutrient-amended soils was also confirmed by comparing their abundance over time to that of the conserved diesel biomarker, bicyclic sesquiterpanes (BS). During this period, microbial respiration was observed, even at subzero temperatures when unfrozen liquid water was detected during the freeze-thaw period. An increase in culturable heterotrophs and 16S rDNA copy numbers was noted during the freezing phase, and the (14)C-hexadecane mineralization in soil samples obtained from the nutrient-amended tank steadily increased. Hydrocarbon degrading bacterial populations identified as Corynebacterineae- and Alkanindiges-related strains emerged during the freezing and thawing phases, respectively, indicating there were temperature-based microbial community shifts.

In-situ bioremediation: Or how to get nutrients to all the contaminated soil

International Nuclear Information System (INIS)

Jackson, D.S.; Scovazzo, P.

1994-01-01

Petroleum contamination is a pervasive environmental problem. Bioremediation is winning favor primarily because the soil may be treated on site and systems can be installed to operate without interfering with facility activities. Although bioremediation has been utilized for many years, its acceptance as a cost-effective approach is only now being realized. KEMRON applied in-situ bioremediation at a retired rail yard which had maintained a diesel locomotive refueling station supplied by two 20,000 gallon above ground storage tanks. Contamination originated from both spillage at the pumps and leaking fuel distribution lines. The contamination spread over a 3 acre area from the surface to a depth of up to 20 feet. Levels of diesel contamination found in the soil ranged from less than a 100 ppm to more than 25,000 ppm. The volume of soil which ultimately required treatment was more than 60,000 cubic yards. Several remedial options were examined including excavation and disposal. Excavation was rejected because it would have been cost prohibitive due to the random distribution of the contaminated soil. In-situ Bioremediation was selected as the only alternative which could successfully treat all the contaminated soils. This paper focuses on how KEMRON solved four major problems which would have prevented a successful remediation project. These problems were: soil compaction, random distribution of contaminated soils, potential free product, and extremely high levels of dissolved iron in the groundwater

Bioventing of gasoline-contaminated soil: some questions to be answered

International Nuclear Information System (INIS)

Bezerra, S.M.C.; Zytner, R.G.

2002-01-01

Underground storage tank (UST) leakage is a big concern in the USA and Canada because gasoline-contaminated soil is a significant source of groundwater contamination. This threat is not confined to North America as locations like Sao Paulo (Brazil) have leakage rates similar to the North American average. The typical in-situ remediation technology used to remediate the contaminated soil is soil vapour extraction (SVE), but once tailing occurs, where the residual gasoline concentration still exceeds clean up levels, SVE becomes ineffective. Bioventing has emerged as one of the most cost-effective technologies currently available to address this tailing in the remediation of petroleum-contaminated sites. Bioventing is a source control treatment, which delivers air and nutrients through injection wells placed in contaminated areas, in order to stimulate the activity of the indigenous microorganisms. However, encouraging laboratory results have not always translated into similar outcomes when implemented in the field. A reason for this inconsistency is the scale-dependent phenomena that influence the bioventing process at the microscale, mesoscale, and macroscale. This paper intends to provide some insights about various research needs in order to improve the bioventing process, specifically related to predicting the time to reach site closure. (author)

Failure analysis of buried tanks

International Nuclear Information System (INIS)

Watkins, R.K.

1994-01-01

Failure of a buried tank can be hazardous. Failure may be a leak through which product is lost from the tank; but also through which contamination can occur. Failures are epidemic -- because buried tanks are out of sight, but also because designers of buried tanks have adopted analyses developed for pressure tanks. So why do pressure tanks fail when they are buried? Most failures of buried tanks are really soil failures. Soil compresses, or slips, or liquefies. Soil is not only a load, it is a support without which the tank deforms. A high water table adds to the load on the tank. It also reduces the strength of the soil. Based on tests, structural analyses are proposed for empty tanks buried in soils of various quality, with the water table at various levels, and with internal vacuum. Failure may be collapse tank. Such collapse is a sudden, audible inversion of the cylinder when the sidefill soil slips. Failure may be flotation. Failure may be a leak. Most leaks are fractures in the welds in overlap seams at flat spots. Flat spots are caused by a hard bedding or a heavy surface wheel load. Because the tank wall is double thick at the overlap, shearing stress in the weld is increased. Other weld failures occur when an end plate shears down past a cylinder; or when the tank is supported only at its ends like a beam. These, and other, failures can be analyzed with justifiable accuracy using basic principles of mechanics of materials. 10 figs

AX Tank farm closure settlement estimates and soil testing; TOPICAL

International Nuclear Information System (INIS)

BECKER, D.L.

1999-01-01

This study provides a conservative three-dimensional settlement study of the AX Tank Farm closure with fill materials and a surface barrier. The finite element settlement model constructed included the interaction of four tanks and the surface barrier with the site soil and bedrock. Also addressed are current soil testing techniques suitable for the site soil with recommendations applicable to the AX Tank Farm and the planned cone penetration testing

Structural Continuum Modeling of Space Shuttle External Tank Foam Insulation

Science.gov (United States)

Steeve, Brian; Ayala, Sam; Purlee, T. Eric; Shaw, Phillip

2006-01-01

This document is a viewgraph presentation reporting on work in modeling the foam insulation of the Space Shuttle External Tank. An analytical understanding of foam mechanics is required to design against structural failure. The Space Shuttle External Tank is covered primarily with closed cell foam to: Prevent ice, Protect structure from ascent aerodynamic and engine plume heating, and Delay break-up during re-entry. It is important that the foam does not shed unacceptable debris during ascent environment. Therefore a modeling of the foam insulation was undertaken.

Sorption of Emerging Organic Wastewater Contaminants to Four Soils

Directory of Open Access Journals (Sweden)

Sarah Roberts

2014-04-01

Full Text Available Conventional onsite wastewater treatment system design relies on a septic tank and soil treatment unit (STU for treatment of wastewater and integration of the final effluent into the environment. Organic water contaminants (OWCs, chemicals found in pharmaceutical drugs, detergents, surfactants, and other personal care and cleaning products, have been observed in septic tank effluent and the environment. Sorption of OWC mass to soil is a key mechanism in the removal and retardation of many of these chemicals in effluent as it travels through an STU. The primary purpose of this study was to investigate the relationship between the fraction of organic carbon of soil and the equilibrium sorption partitioning coefficient of a selected group of relevant and diverse OWCs. A secondary goal is to evaluate current methods of modeling the sorption of selected OWCs in soil. Five point Freundlich isotherms were constructed from equilibrium sorption batch tests for target OWCs with four different soils. For soils with organic carbon fraction between 0.021 and 0.054, Kd values were calculated between 60 and 185 for 4-nonylphenol, 75 to 260 for triclosan, 115 to 270 for bisphenol-A, 3 to 255 for 17β-estradiol, 40 to 55 for 17α-ethynylestradiol, and 28 to 70 for estrone. An empirically derived, direct relationship between foc and Kd may be a useful approach to estimating sorption for a soil based on organic carbon content.

NCRP soil contamination task group

International Nuclear Information System (INIS)

Jacobs, D.G.

1987-01-01

The National Council of Radiation Protection and Measurements (NCRP) has recently established a Task Group on Soil Contamination to describe and evaluate the migration pathways and modes of radiation exposure that can potentially arise due to radioactive contamination of soil. The purpose of this paper is to describe the scientific principles for evaluation of soil contamination which can be used as a basis for derivation of soil contamination limits for specific situations. This paper describes scenarios that can lead to soil contamination, important characteristics of soil contamination, the subsequent migration pathways and exposure modes, and the application of principles in the report in deriving soil contamination limits. The migration pathways and exposure modes discussed in this paper include: direct radiation exposure; and exhalation of gases

Reduction of polycyclic aromatic hydrocarbons (PAHs) from petroleum-contaminated soil using thermal desorption technology

International Nuclear Information System (INIS)

Silkebakken, D.M.; Davis, H.A.; Ghosh, S.B.; Beardsley, G.P.

1995-01-01

The remediation of petroleum-contaminated soil typically requires the selection of a treatment option that addresses the removal of both volatile and semi-volatile organic compounds. Volatile organic compounds (VOCs), primarily BTEX (benzene, toluene, ethylbenzene, and xylenes) compounds, can be readily removed from the soil by a variety of well-established technologies. The semivolatile organic compounds, especially the polycyclic aromatic hydrocarbons (PAHS) that are characteristic of petroleum-contaminated soil, are not as amenable to conventional treatment. Low temperature thermal volatilization (LTTV) can be a viable treatment technology depending on the initial contaminant concentrations present and applicable cleanup objectives that must be attained. A-two-phase treatability study was conducted at 14 former underground storage tank (UST) sites to evaluate the applicability and effectiveness of LTTV for remediation of approximately 31,000 tons of PAH-contaminated soil. The PAHs of primary concern included benzo(a)anthracene, chrysene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(g,h,i)perylene, dibenz(a,h) anthracene, and indeno(1,2,3-cd)pyrene. During Phase 1, LTTV operational parameters were varied by trial-and-error and changes in soil treatment effectiveness were monitored. Phase B of the treatability study incorporated the appropriate treatment regime established during Phase 1 to efficiently remediate the remaining contaminated soil

Tank 241-AX-104 upper vadose zone cone penetrometer demonstration sampling and analysis plan

International Nuclear Information System (INIS)

FIELD, J.G.

1999-01-01

This sampling and analysis plan (SAP) is the primary document describing field and laboratory activities and requirements for the tank 241-AX-104 upper vadose zone cone penetrometer (CP) demonstration. It is written in accordance with Hanford Tank Initiative Tank 241-AX-104 Upper Vadose Zone Demonstration Data Quality Objective (Banning 1999). This technology demonstration, to be conducted at tank 241-AX-104, is being performed by the Hanford Tanks Initiative (HTI) Project as a part of Tank Waste Remediation System (TWRS) Retrieval Program (EM-30) and the Office of Science and Technology (EM-50) Tanks Focus Area. Sample results obtained as part of this demonstration will provide additional information for subsequent revisions to the Retrieval Performance Evaluation (RPE) report (Jacobs 1998). The RPE Report is the result of an evaluation of a single tank farm (AX Tank Farm) used as the basis for demonstrating a methodology for developing the data and analyses necessary to support making tank waste retrieval decisions within the context of tank farm closure requirements. The RPE includes a study of vadose zone contaminant transport mechanisms, including analysis of projected tank leak characteristics, hydrogeologic characteristics of tank farm soils, and the observed distribution of contaminants in the vadose zone in the tank farms. With limited characterization information available, large uncertainties exist as to the nature and extent of contaminants that may exist in the upper vadose zone in the AX Tank Farm. Traditionally, data has been collected from soils in the vadose zone through the installation of boreholes and wells. Soil samples are collected as the bore hole is advanced and samples are screened on site and/or sent to a laboratory for analysis. Some in-situ geophysical methods of contaminant analysis can be used to evaluate radionuclide levels in the soils adjacent to an existing borehole. However, geophysical methods require compensation for well

Pore Water Extraction Test Near 241-SX Tank Farm at the Hanford Site, Washington, USA

International Nuclear Information System (INIS)

Eberlein, Susan J.; Parker, Danny L.; Tabor, Cynthia L.; Holm, Melissa J.

2013-01-01

A proof-of-principle test is underway near the Hanford Site 241-SX Tank Farm. The test will evaluate a potential remediation technology that will use tank farm-deployable equipment to remove contaminated pore water from vadose zone soils. The test system was designed and built to address the constraints of working within a tank farm. Due to radioactive soil contamination and limitations in drilling near tanks, small-diameter direct push drilling techniques applicable to tank farms are being utilized for well placement. To address space and weight limitations in working around tanks and obstacles within tank farms, the above ground portions of the test system have been constructed to allow deployment flexibility. The test system utilizes low vacuum over a sealed well screen to establish flow into an extraction well. Extracted pore water is collected in a well sump,and then pumped to the surface using a small-diameter bladder pump.If pore water extraction using this system can be successfully demonstrated, it may be possible to target local contamination in the vadose zone around underground storage tanks. It is anticipated that the results of this proof-of-principle test will support future decision making regarding interim and final actions for soil contamination within the tank farms

Restoration of contaminated soils

International Nuclear Information System (INIS)

Miranda J, Jose Eduardo

2009-01-01

A great variety of techniques are used for the restoration of contaminated soils. The contamination is present by both organic and inorganic pollutants. Environmental conditions and soil characteristics should take into account in order to implement a remedial technique. The bioremediation technologies are showed as help to remove a variety of soil contaminants. (author) [es

Simultaneous removal of phenanthrene and cadmium from contaminated soils by saponin, a plant-derived biosurfactant

International Nuclear Information System (INIS)

Song Saisai; Zhu Lizhong; Zhou Wenjun

2008-01-01

Batch experiments were conducted to evaluate the performance of saponin, a plant-derived biosurfactant, for simultaneously removing phenanthrene and cadmium from the combined contaminated soils. Results showed that phenanthrene was desorbed from the contaminated soils by saponin with the partition of phenanthrene into surfactant micelle, meanwhile cadmium was effectively removed from the contaminated soils by the complexation of cadmium with the external carboxyl groups of saponin micelle. The efficiencies of saponin for the removal of phenanthrene and cadmium from the contaminated soils were greater than that of Triton X100 and citric acid, respectively. At concentration of 3750 mg/L, saponin has a removal rate of 87.7% and 76.2% of cadmium and phenanthrene, respectively, from the combined contaminated soil. The removals of cadmium and phenanthrene from the soils were not obviously constrained each other. Thus, saponin has the potential for the removal of heavy metal and PAHs from the combined contaminated soils. - Saponin has great potential for the simultaneous removal of cadmium and phenanthrene from the combined contaminated soils

Simultaneous removal of phenanthrene and cadmium from contaminated soils by saponin, a plant-derived biosurfactant

Energy Technology Data Exchange (ETDEWEB)

Song Saisai [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China); Zhu Lizhong [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China)], E-mail: zlz@zju.edu.cn; Zhou Wenjun [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China)

2008-12-15

Batch experiments were conducted to evaluate the performance of saponin, a plant-derived biosurfactant, for simultaneously removing phenanthrene and cadmium from the combined contaminated soils. Results showed that phenanthrene was desorbed from the contaminated soils by saponin with the partition of phenanthrene into surfactant micelle, meanwhile cadmium was effectively removed from the contaminated soils by the complexation of cadmium with the external carboxyl groups of saponin micelle. The efficiencies of saponin for the removal of phenanthrene and cadmium from the contaminated soils were greater than that of Triton X100 and citric acid, respectively. At concentration of 3750 mg/L, saponin has a removal rate of 87.7% and 76.2% of cadmium and phenanthrene, respectively, from the combined contaminated soil. The removals of cadmium and phenanthrene from the soils were not obviously constrained each other. Thus, saponin has the potential for the removal of heavy metal and PAHs from the combined contaminated soils. - Saponin has great potential for the simultaneous removal of cadmium and phenanthrene from the combined contaminated soils.

Bioventing feasibility study of low permeability soils for remediation of petroleum contamination

International Nuclear Information System (INIS)

Brackney, K.M.

1994-01-01

A site characterization of leaking underground gasoline and diesel storage tanks at the University of Idaho, West Farm Operations Center, identified approximately 800 cubic yards of petroleum-contaminated soil exceedingly regulatory action limits of 100 ppm TPH. Bioventing, a combination of in situ soil vapor extraction and microbial degradation, was selected as a remedial alternative on the basis of the presumably unsaturated paleo-soil with a 45-foot depth to groundwater, and a microbial study which concluded that indigenous petroleum-degrading microorganisms existed throughout the contamination. Soil vapor extraction tests were conducted by applying a 60-inch water column vacuum to a soil vapor extraction well and monitoring pneumatic pressure drawdown in 12 adjacent pneumatic piezometers and vertically distributed piezometer clusters. Pressure drawdown vs time data plots indicated that air permeability is inadequate everywhere at the site except at 20 feet below ground surface. Low soil permeability creates conditions for a perched water table that was documented during the investigation, resulting in unsatisfactory conditions for in situ bioventing. 8 refs., 14 figs

Landfarming of phthalate ester-contaminated soil: Two years of bioremediation results

International Nuclear Information System (INIS)

Kunze, C.M.; Yu, J.; Wilson, S.; Rezin, J.L.; Andronico, A.

1995-01-01

Biorem Technologies Inc. collaborated with Regal Plastics Corporation over 2 years to clean up approximately 600 cubic yards of soil contaminated with di-2-ethylhexyl phthalate ester (DEHP) and No. 2 fuel oil using a landfarming bioremediation process. The contaminated soils consisted of sandy backfill material which had been excavated during the removal of two underground storage tanks (USTs). In 1994, the initial average DEHP concentration was 4,551 ppm while the TPH concentration was 7,252 ppm. In 1995, the initial DEHP concentration was 1067 ppm while TPH was 3,733 ppm. Prior to the implementation of the project, Biorem Technologies completed a laboratory biofeasibility study to demonstrate that a bacterial culture isolated from the site had the capacity to efficiently degrade DEBP in the soil. It was determined during this study that nitrogen and phosphorus nutrient amendments were needed to promote the bioremediation process. In 1994, the soils were loaded on to a lined treatment bed to a depth of 14--16 in. The bed was covered with a greenhouse structure to eliminate stormwater runoff concerns associated with the contaminated soil. To optimize biodegradation, soil moisture and nutrient levels were adjusted. In 1995, a windrow turner replaced the 1994 tilling system. Tarps were used to cover the piles in place of the greenhouse. A leachate collection system was implemented to contain stormwater and leachate

An Analytical Solution for Cylindrical Concrete Tank on Deformable Soil

Directory of Open Access Journals (Sweden)

Shirish Vichare

2010-07-01

Full Text Available Cylindrical concrete tanks are commonly used in wastewater treatment plants. These are usually clarifier tanks. Design codes of practice provide methods to calculate design forces in the wall and raft of such tanks. These methods neglect self-weight of tank material and assume extreme, namely ‘fixed’ and ‘hinged’ conditions for the wall bottom. However, when founded on deformable soil, the actual condition at the wall bottom is neither fixed nor hinged. Further, the self-weight of the tank wall does affect the design forces. Thus, it is required to offer better insight of the combined effect of deformable soil and bottom raft stiffness on the design forces induced in such cylindrical concrete tanks. A systematic analytical method based on fundamental equations of shells is presented in this paper. Important observations on variation of design forces across the wall and the raft with different soil conditions are given. Set of commonly used tanks, are analysed using equations developed in the paper and are appended at the end.

Measurement of soil contamination by radionuclides due to the Fukushima Dai-ichi Nuclear Power Plant accident and associated estimated cumulative external dose estimation

International Nuclear Information System (INIS)

Endo, S.; Kimura, S.; Takatsuji, T.; Nanasawa, K.; Imanaka, T.; Shizuma, K.

2012-01-01

Soil sampling was carried out at an early stage of the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident. Samples were taken from areas around FDNPP, at four locations northwest of FDNPP, at four schools and in four cities, including Fukushima City. Radioactive contaminants in soil samples were identified and measured by using a Ge detector and included 129m Te, 129 Te, 131 I, 132 Te, 132 I, 134 Cs, 136 Cs, 137 Cs, 140 Ba and 140 La. The highest soil depositions were measured to the northwest of FDNPP. From this soil deposition data, variations in dose rates over time and the cumulative external doses at the locations for 3 months and 1 y after deposition were estimated. At locations northwest of FDNPP, the external dose rate at 3 months after deposition was 4.8–98 μSv/h and the cumulative dose for 1 y was 51 to 1.0 × 10 3 mSv; the highest values were at Futaba Yamada. At the four schools, which were used as evacuation shelters, and in the four urban cities, the external dose rate at 3 months after deposition ranged from 0.03 to 3.8 μSv/h and the cumulative doses for 1 y ranged from 3 to 40 mSv. The cumulative dose at Fukushima Niihama Park was estimated as the highest in the four cities. The estimated external dose rates and cumulative doses show that careful countermeasures and remediation will be needed as a result of the accident, and detailed measurements of radionuclide deposition densities in soil will be important input data to conduct these activities.

Potential reuse of petroleum-contaminated soil: A directory of permitted recycling facilities

International Nuclear Information System (INIS)

Rosenthal, S.; Wolf, G.; Avery, M.; Nash, J.H.

1992-06-01

Soil contaminated by virgin petroleum products leaking from underground storage tanks is a pervasive problem in the United States. Economically feasible disposal of such soil concerns the responsible party (RP), whether the RP is one individual small business owner, a group of owners, or a large multinational corporation. They may need a starting point in their search for an appropriate solution, such as recycling. The report provides initial assistance in two important areas. First it discusses four potential recycling technologies that manufacture marketable products from recycled petroleum-contaminated soil: the hot mix asphalt process, the cold mix asphalt system, cement production, and brick manufacturing. The report also presents the results of a project survey designed to identify recycling facilities. It lists recycling facilities alphabetically by location within each state, organized by U.S. Environmental Protection Agency (EPA) Region. The report also includes detailed addresses, recycling locations, telephone numbers, and contacts for these facilities. The scope of the project limits listings to fixed facilities or small mobile facility owners that recycle soil contaminated by virgin petroleum products into marketable commodities. It does not address site-specific or commercial hazardous waste remediation facilities

WVNS Tank Farm Process Support: Experimental evaluation of an inert gas (nitrogen) to mitigate external corrosion of high-level waste storage tanks

International Nuclear Information System (INIS)

Elmore, M.R.

1996-02-01

Corrosion of the carbon steel waste storage tanks at West Valley Nuclear Services continues to be of concern, especially as the planned duration of waste storage time increases and sludge washing operations are conducted. The external surfaces of Tanks 8D-1 and 8D-2 have been exposed for more than 10 years to water that has intruded into the tank vaults. Visual inspection of the external tank surfaces using a remote video camera has shown indications of heavy corrosion in localized areas on the tank walls. Tests on mild steel specimens under simulated tank vault conditions showed that corrosion is related to the availability of oxygen for the corrosion reactions; consequently, removing oxygen as one of the reactants should effectively eliminate corrosion. In terms of the waste tanks, excluding oxygen from the annular vault space, such as by continuous flushing with an inert gas, should substantially decrease corrosion of the external surfaces of the mild steel tanks (100% exclusion of oxygen is probably not practicable). Laboratory corrosion testing was conducted at Pacific Northwest National Laboratory to give a preliminary assessment of the ability of nitrogen-inerting to reduce steel corrosion. This report summarizes test results obtained after 18-month corrosion tests comparing open-quotes nitrogen-inertedclose quotes corrosion with open-quotes air-equilibratedclose quotes corrosion under simulated tank vault conditions

Enhancement of in situ Remediation of Hydrocarbon Contaminated Soil

Energy Technology Data Exchange (ETDEWEB)

Palmroth, M.

2006-07-01

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

49 CFR Appendix D to Part 238 - Requirements for External Fuel Tanks on Tier I Locomotives

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Requirements for External Fuel Tanks on Tier I..., App. D Appendix D to Part 238—Requirements for External Fuel Tanks on Tier I Locomotives The... properties of the locomotive fuel tank to reduce the risk of fuel spillage to acceptable levels under...

Assessment of contamination by percolation of septic tank effluent through natural and amended soils.

Science.gov (United States)

Cheung, K C; Venkitachalam, T H

2004-01-01

Fly ash has been found to be a potential material for the treatment of municipal and industrial wastewater, and may be useful in the treatment of septic tank effluent. Laboratory columns (30 cm) were used to determine the sorption capacity and hydraulic properties of lagoon fly ash, loamy sand, sand, and sand amended by lagoon fly ash (30 and 60%) and red mud gypsum (20%). The removal of chemical oxygen demand (COD) was high in all column effluents (71-93%). Extent of nitrification was high in Spearwood sand, Merribrook loamy sand and 20% red mud gypsum amended Spearwood sand. However, actual removal of nitrogen (N) was high in columns containing lagoon fly ash. Unamended Spearwood sand possessed only minimal capacity for P sorption. Merribrook loamy sand and red mud gypsum amended sand affected complete P removal throughout the study period of 12 weeks. Significant P leakage occurred from lagoon fly ash amended sand columns following 6-10 weeks of operation. Neither lagoon fly ash nor red mud gypsum caused any studied heavy metal contamination including manganese (Mn), lead (Pb), zinc (Zn), cadmium (Cd) and chromium (Cr) of effluent. It can be concluded that Merribrook loamy sand is better natural soil than Spearwood sand as a filter medium. The addition of lagoon fly ash enhanced the removal of P in Spearwood sand but the efficiency was lower than with red mud gypsum amendment.

Bioremediation of contaminated soil

International Nuclear Information System (INIS)

Balba, M.T.; Ying, A.C.; McNeice, T.G.

1992-01-01

Microorganisms, especially bacteria, yeast and fungi are capable of degrading many kinds of xenobiotic compounds and toxic chemicals such as petroleum hydrocarbon compounds. These microorganisms are ubiquitous in nature and, despite their enormous versatility, there are numerous cases in which long-term contamination of soil and groundwater has been observed. The persistence of the contamination is usually caused by the inability of microorganisms to metabolize these compounds under the prevailing environmental condition. This paper reports on biological remediation of contaminated sites which can be accomplished by using naturally-occurring microorganisms to treat the contaminants. The development of a bioremediation program for a specific contaminated soil system usually includes: A thorough site/soil/waste characterization; Treatability studies

Remaining Sites Verification Package for the 600-243 Petroleum-Contaminated Soil Bioremediation Pad. Attachment to Waste Site Reclassification Form 2007-033

International Nuclear Information System (INIS)

Capron, J.M.

2008-01-01

The 600-243 waste site consisted of a bioremediation pad for petroleum-contaminated soils resulting from the 1100 Area Underground Storage Tank (UST) upgrades in 1994. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River

External Fuel Tank, Clouds and Earth Limb

Science.gov (United States)

1991-01-01

It's fuel consumed, the expendable external fuel tank was jettisoned moments earlier from the Space Shuttle Atlantis and now begins its plunge back to Earth (20.5N, 36.0W). Backdropped against the void of space and the thin blue line of the Earth's airglow above the Earth Limb, the harshness of the blackness of space is softened by the fleeciness of Earth's cloud cover below.

Underground tank remediation by use of in situ vitrification

International Nuclear Information System (INIS)

Thompson, L.E.

1991-02-01

Pacific Northwest Laboratory (PNL) is developing a remedial action technology for underground storage tanks through the adaptation of the in situ vitrification (ISV) process. The ISV process is a thermal treatment processes that was originally developed for the stabilization of contaminated soil contaminated with transuranic waste at the Hanford Site in southeastern Washington for the Department of Energy (DOE). The application of ISV to underground storage tanks represents an entirely new application of the ISV technology and is being performed in support of the DOE primarily for the Hanford site and the Oak Ridge National Laboratory (ORNL). A field scale test was conducted in September 1990 at Hanford on a small cement and stainless steel tank (1-m dia.) that contained a simulated refractory sludge representing a worst-case sludge composition. The tank design and sludge composition was based on conditions present at the ORNL. The sludge contained high concentrations of heavy metals including lead, mercury, and cadmium, and also contained high levels of stable cesium and strontium to represent the predominant radionuclide species present in the tank wastes. The test was highly successful in that the entire tank and surrounding soil was transformed into a highly leach resistant glass and crystalline block with a mass of approximately 30 tons. During the process, the metal shell of the tank forms a metal pool at the base of the molten soil. Upon cooling, the glass and metal phases were subjected to TCLP (toxic characteristic leach procedure) testing and passed the TCLP criteria. Additional sampling and analyses are ongoing to determine the bulk composition of the waste forms, the fraction of volatile or semi-volatile species released to the off-gas treatment system, and to determine whether any soil surrounding the monolith was contaminated as a result of the ISV process. 4 refs., 5 figs., 3 tabs

Biopiles - demonstration of cost effective biological remediation of furnace oil contaminated soils

International Nuclear Information System (INIS)

Kirchmair, G.A.

1998-01-01

Approximately 900 tonnes of soil was contaminated at a rural manufacturing facility near Collingwood, Ontario, when a 9000 litre underground furnace oil storage tank sprang a leak. The contaminated soil was excavated and stockpiled at the site and the leak was repaired. The Ontario Ministry of the Environment ordered that the owner treat the soil to the proper criteria or have the soil removed from the site and properly disposed of at a licensed landfill facility. Barenco was hired to treat the soil. Bioremediation began in December 1994 with the creation of nine above-ground biopiles which were constructed through the addition of nutrients (manure from a local farmer). Piping for air injection and treatment were located throughout the biopiles. The biopiles were then covered with 6 mil black HDPE plastic. The progress of the bioremediation was monitored regularly through measurement of carbon dioxide and oxygen concentrations in the biopiles. By October 1995, the soil was treated to within the appropriate criteria. In 10 months, the total petroleum hydrocarbon concentrations in the polluted soil were reduced from an average of 2690 ppm to 275 ppm. This simple and cost effective approach can also be used to remediate soils impacted with diesel fuels

Soil structure interaction analysis for the Hanford Site 241-SY-101 double-shell waste storage tanks

International Nuclear Information System (INIS)

Giller, R.A.; Weiner, E.O.

1991-09-01

The 241-SY-101 tank is a double-shell waste storage tank buried in the 241-SY tank farm in the 200 West Area of the Hanford Site. This analysis addresses the effects of seismic soil-structure interaction on the tank structure and includes a parametric soil-structure interaction study addressing three configurations: two-dimensional soil structure, a two-dimensional structure-soil-structure, and a three-dimensional soil-structure interaction. This study was designed to determine an optimal method for addressing seismic-soil effects on underground storage tanks. The computer programs calculate seismic-soil pressures on the double-shell tank walls and and seismic acceleration response spectra in the tank. The results of this soil-structure interaction parametric study as produced by the computer programs are given in terms of seismic soil pressures and response spectra. The conclusions of this soil-structure interaction evaluation are that dynamically calculated soil pressures in the 241-SY-101 tank are significantly reduce from those using standard hand calculation methods and that seismic evaluation of underground double-shell waste storage tanks must consider soil-structure interaction effects in order to predict conservative structural response. Appendixes supporting this study are available in Volume 2 of this report

Bench Scale Treatability Studies of Contaminated Soil Using Soil Washing Technique

Directory of Open Access Journals (Sweden)

M. K. Gupta

2010-01-01

Full Text Available Soil contamination is one of the most widespread and serious environmental problems confronting both the industrialized as well as developing nations like India. Different contaminants have different physicochemical properties, which influence the geochemical reactions induced in the soils and may bring about changes in their engineering and environmental behaviour. Several technologies exist for the remediation of contaminated soil and water. In the present study soil washing technique using plain water with surfactants as an enhancer was used to study the remediation of soil contaminated with (i an organic contaminant (engine lubricant oil and (ii an inorganic contaminant (heavy metal. The lubricant engine oil was used at different percentages (by dry weight of the soil to artificially contaminate the soil. It was found that geotechnical properties of the soil underwent large modifications on account of mixing with the lubricant oil. The sorption experiments were conducted with cadmium metal in aqueous medium at different initial concentration of the metal and at varying pH values of the sorbing medium. For the remediation of contaminated soil matrices, a nonionic surfactant was used for the restoration of geotechnical properties of lubricant oil contaminated soil samples, whereas an anionic surfactant was employed to desorb cadmium from the contaminated soil matrix. The surfactant in case of soil contaminated with the lubricant oil was able to restore properties to an extent of 98% vis-à-vis the virgin soil, while up to 54% cadmium was desorbed from the contaminated soil matrix in surfactant aided desorption experiments.

The Use of Modified Bentonite for Removal of Aromatic Organics from Contaminated Soil.

Science.gov (United States)

Gitipour; Bowers; Bodocsi

1997-12-15

This study investigates the clay-aromatic interactions with a view to the use of bentonite clay for binding benzene, toluene, ethylbenzene, and o-xylene (BTEX compounds) in contaminated soils. BTEX compounds are the most toxic aromatic constituents of gasoline present in many underground storage tanks. Modified (organophilic) and ordinary bentonites are used to remove these organics. The organophilic bentonites are prepared by replacing the exchangeable inorganic cations present in bentonite particles with a quaternary ammonium salt. Various clay-to-soil ratios were applied to determine the efficiency of the modified bentonite in enhancing the cement-based solidification/stabilization (S/S) of BTEX contaminated soils. Toxicity characteristics leaching procedure (TCLP) tests were performed on soil samples to evaluate the leaching of the organics. In addition, X-ray diffraction analyses were conducted to assess the changes in the basal spacing of the clays as a result of their interaction with BTEX compounds. The findings of this study reveal that organophilic bentonite can act as a successful adsorbent for removing the aromatic organics from contaminated soil. Thus, this material is viable for enhancing the performance of cement-based S/S processes, as an adsorbent for petroleum spills, and for landfill liners and slurry walls. Copyright 1997 Academic Press.

The use of modified bentonite for removal of aromatic organics from contaminated soil

International Nuclear Information System (INIS)

Gitipour, S.; Bowers, M.T.; Bodocsi, A.

1997-01-01

This study investigates the clay-aromatic interactions with a view to the use of bentonite clay for binding benzene, toluene, ethylbenzene, and o-xylene (BTEX compounds) in contaminated soils. BTEX compounds are the most toxic aromatic constituents of gasoline present in many underground storage tanks. Modified (organophilic) and ordinary bentonites are used to remove these organics. The organophilic bentonites are prepared by replacing the exchangeable inorganic cations present in bentonite particles with a quaternary ammonium salt. Various clay-to-soil ratios were applied to determine the efficiency of the modified bentonite in enhancing the cement-based solidification/stabilization (S/S) of BTEX contaminated soils. Toxicity characteristics leaching procedure (TCLP) tests were performed on soil samples to evaluate the leaching of the organics. In addition, X-ray diffraction analyses were conducted to assess the changes in the basal spacing of the clays as a result of their interaction with BTEX compounds. The findings of this study reveal that organophilic bentonite can act as a successful adsorbent for removing the aromatic organics from contaminated soil. Thus, this material is viable for enhancing the performance of cement-based S/S processes, as an adsorbent for petroleum spills, and for landfill liners and slurry walls

External corrosion of tanks 8D-1 and 8D-2. Final report

International Nuclear Information System (INIS)

Mackey, D.B.; Westerman, R.E.

1995-05-01

Tanks 8D-1 and 8D-2 at the West Valley Nuclear Services (WVNS) site, West Valley, New York, rest on layers of perlite brick contained within steel pans. The pans tend to collect water, which can contact the tanks directly and which also can be ''wicked'' to the external surfaces of the tank through the perlite brick. The presence of air in the tank vault is conducive to the formation of oxygen concentration cells, which can promote localized corrosion of the carbon steel tank wall. Pacific Northwest Laboratory conducted an experiment to estimate the extent to which the external surfaces of the tanks could have corroded in the 30 years since their construction. Specimens of carbon steel, similar to that used in the tank construction, were partially embedded in an upright position in particulate perlite in closed containers. The water line in the containers.was maintained at two levels: above the perlite level (high water level tests) and below the bottoms of the specimens (low water level tests). The water used in the tests was obtained from the pan of tank 8D-1. The containers were maintained in an aerated condition. Specimens were examined after 3-, 6-, 12-, 18-, 24-, and 30-month exposures

Distribution and Source Identification of Pb Contamination in industrial soil

Science.gov (United States)

Ko, M. S.

2017-12-01

INTRODUCTION Lead (Pb) is toxic element that induce neurotoxic effect to human, because competition of Pb and Ca in nerve system. Lead is classified as a chalophile element and galena (PbS) is the major mineral. Although the Pb is not an abundant element in nature, various anthropogenic source has been enhanced Pb enrichment in the environment after the Industrial Revolution. The representative anthropogenic sources are batteries, paint, mining, smelting, and combustion of fossil fuel. Isotope analysis widely used to identify the Pb contamination source. The Pb has four stable isotopes that are 208Pb, 207Pb, 206Pb, and 204Pb in natural. The Pb is stable isotope and the ratios maintain during physical and chemical fractionation. Therefore, variations of Pb isotope abundance and relative ratios could imply the certain Pb contamination source. In this study, distributions and isotope ratios of Pb in industrial soil were used to identify the Pb contamination source and dispersion pathways. MATERIALS AND METHODS Soil samples were collected at depth 0­-6 m from an industrial area in Korea. The collected soil samples were dried and sieved under 2 mm. Soil pH, aqua-regia digestion and TCLP carried out using sieved soil sample. The isotope analysis was carried out to determine the abundance of Pb isotope. RESULTS AND DISCUSSION The study area was developed land for promotion of industrial facilities. The study area was forest in 1980, and the satellite image show the alterations of land use with time. The variations of land use imply the possibilities of bringing in external contaminated soil. The Pb concentrations in core samples revealed higher in lower soil compare with top soil. Especially, 4 m soil sample show highest Pb concentrations that are approximately 1500 mg/kg. This result indicated that certain Pb source existed at 4 m depth. CONCLUSIONS This study investigated the distribution and source identification of Pb in industrial soil. The land use and Pb

Soil structural analysis tools and properties for Hanford site waste tank evaluation

International Nuclear Information System (INIS)

Moore, C.J.; Holtz, R.D.; Wagenblast, G.R.; Weiner, E.D.; Marlow, R.S.

1995-09-01

As Hanford Site contractors address future structural demands on nuclear waste tanks, built as early as 1943, it is necessary to address their current safety margins and ensure safe margins are maintained. Although the current civil engineering practice guidelines for soil modeling are suitable as preliminary design tools, future demands potentially result in loads and modifications to the tanks that are outside the original design basis and current code based structural capabilities. For example, waste removal may include cutting a large hole in a tank. This report addresses both spring modeling of site soils and finite-element modeling of soils. Additionally seismic dynamic modeling of Hanford Site soils is also included. Of new and special interest is Section 2.2 that Professor Robert D. Holtz of the University of Washington wrote on plane strain soil testing versus triaxial testing with Hanford Site application to large buried waste tanks

Soil structural analysis tools and properties for Hanford site waste tank evaluation

Energy Technology Data Exchange (ETDEWEB)

Moore, C.J.; Holtz, R.D.; Wagenblast, G.R.; Weiner, E.D.; Marlow, R.S.

1995-09-01

As Hanford Site contractors address future structural demands on nuclear waste tanks, built as early as 1943, it is necessary to address their current safety margins and ensure safe margins are maintained. Although the current civil engineering practice guidelines for soil modeling are suitable as preliminary design tools, future demands potentially result in loads and modifications to the tanks that are outside the original design basis and current code based structural capabilities. For example, waste removal may include cutting a large hole in a tank. This report addresses both spring modeling of site soils and finite-element modeling of soils. Additionally seismic dynamic modeling of Hanford Site soils is also included. Of new and special interest is Section 2.2 that Professor Robert D. Holtz of the University of Washington wrote on plane strain soil testing versus triaxial testing with Hanford Site application to large buried waste tanks.

Tank farms backlog soil sample and analysis results supporting a contained-in determination

Energy Technology Data Exchange (ETDEWEB)

Jackson, C.L., Fluor Daniel Hanford

1997-02-27

Soil waste is generated from Tank Farms and associated Tank Farms facilities operations. The soil is a mixed waste because it is an environmental media which contains tank waste, a listed mixed waste. The soil is designated with the listed waste codes (FOO1 through F005) which have been applied to all tank wastes. The scope of this report includes Tank Farms soil managed under the Backlog program. The Backlog Tank Farm soil in storage consists of drums and 5 boxes (originally 828 drums). The Backlog Waste Program dealt with 2276 containers of solid waste generated by Tank Farms operations during the time period from 1989 through early 1993. The containers were mismanaged by being left in the field for an extended period of time without being placed into permitted storage. As a corrective action for this situation, these containers were placed in interim storage at the Central Waste Complex (CWC) pending additional characterization. The Backlog Waste Analysis Plan (BWAP) (RL 1993) was written to define how Backlog wastes would be evaluated for proper designation and storage. The BWAP was approved in August 1993 and all work required by the BWAP was completed by July 1994. This document presents results of testing performed in 1992 & 1996 that supports the attainment of a Contained-In Determination for Tank Farm Backlog soils. The analytical data contained in this report is evaluated against a prescribed decision rule. If the decision rule is satisfied then the Washington State Department of ecology (Ecology) may grant a Contained-In Determination. A Contained-In Determination for disposal to an unlined burial trench will be requested from Ecology . The decision rule and testing requirements provided by Ecology are described in the Tank Farms Backlog Soil Sample Analysis Plan (SAP) (WHC 1996).

Use of a horizontal air-dispersion system to enhance biodegradation of diesel fuel contaminated soils

International Nuclear Information System (INIS)

Baker, J.N.; Nickerson, D.A.; Guest, P.R.; Portele, T.E.

1993-01-01

A horizontal air-dispersion system was designed and installed to enhance the natural biodegradation of residual diesel fuel contaminated soils at an underground storage tank (UST) facility in Seattle, Washington. This system was designed to operate in conjunction with an existing free-product recovery system which exposes more heavily contaminated soils at the capillary fringe to injected air. Results of a pilot study conducted at the facility indicate that an initial biodegradation rate of 2,200 mg of total petroleum hydrocarbons (TPH) per kg of soil per year will be achieved, making in-situ biodegradation a feasible remedial alternative for contaminated site soils. Oxygen, carbon dioxide, and hydrocarbon vapor concentrations have been monitored since full-scale startup in September 1992, using a series of vapor monitoring points (VMPs) installed in the vicinity of the aerated beds and around the perimeter of the facility. Recent monitoring data indicate that the system is capable of aerating soils at distances greater than 80 feet from the aerated beds. Oxygen utilization and carbon dioxide production measured during post-startup respiration tests indicate microbial activity has increased as a result of seven months of full-scale system operation

Applying FDEM, ERT and GPR at a site with soil contamination: A case study

Science.gov (United States)

Wang, Tzu-Pin; Chen, Chien-Chih; Tong, Lun-Tao; Chang, Ping-Yu; Chen, Yi-Chieh; Dong, Tien-Hsing; Liu, Hsin-Chang; Lin, Chih-Ping; Yang, Kai-Hsing; Ho, Ching-Jen; Cheng, Shih-Nan

2015-10-01

This study employed the combination of three methods, namely the Frequency Domain Electromagnetic (FDEM), Electrical Resistivity Tomography (ERT) and Ground Penetrating Radar (GPR) to evaluate a heavy-metal contaminated site for both pre- and post-remediation investigations. The main goals were to verify the position and the integrity of the underground storage tanks (UST), and to determine the effectiveness of remediation to ensure no contaminants remained at the site. In general, the GPR survey was effective at locating shallowly buried objects. However, due to the highly conductive nature of the heavy-metal laden sludge, the GPR signals were attenuated severely. Thus, the first attempt to use GPR in the pre-remediation investigation did not achieve the desired results and other methods were deployed. The existence of the UST and the sludge within were confirmed by ERT and the UST shape was mapped by FDEM. The principal remediation scheme was soil replacement by replacing the contaminated soil with clean silt. Based on the distinctive property differences of the contaminated soil and the clean silt, the completion of the remediation was confirmed by the differences between pre-remediation and post-remediation in GPR, ERT and FDEM results.

Contaminated soil concrete blocks

NARCIS (Netherlands)

de Korte, A.C.J.; Brouwers, Jos; Limbachiya, Mukesh C.; Kew, Hsein Y.

2009-01-01

According to Dutch law the contaminated soil needs to be remediated or immobilised. The main focus in this article is the design of concrete blocks, containing contaminated soil, that are suitable for large production, financial feasible and meets all technical and environmental requirements. In

Enhanced bioremediation of oil contaminated soil by graded modified Fenton oxidation.

Science.gov (United States)

Xu, Jinlan; Xin, Lei; Huang, Tinglin; Chang, Kun

2011-01-01

Graded modified Fenton's (MF) oxidation is a strategy in which H2O2 is added intermittently to prevent a sharp temperature increase and undesired soil sterilization at soil circumneutral pH versus adding the same amount of H2O2 continuously. The primary objective of the present study was to investigate whether a mild MF pre-oxidation such as a stepwise addition of H2O2 can prevent sterilization and achieve a maximum degradation of tank oil in soil. Optimization experiments of graded MF oxidation were conducted using citric acid, oxalic acid and SOLV-X as iron chelators under different frequencies of H2O2 addition. The results indicated that the activity order of iron chelates decreased as: citric acid (51%) > SOLV-X (44%) > oxalic acid (9%), and citric acid was found to be an optimized iron chelating agent of graded MF oxidation. Three-time addition of H2O2 was found to be favorable and economical due to decreasing total petroleum hydrocarbon removal from three time addition (51%) to five time addition (59%). Biological experiments were conducted after graded MF oxidation of tank oil completed under optimum conditions mentioned above. After graded oxidation, substantially higher increase (31%) in microbial activity was observed with excessive H2O2 (1470 mmol/L, the mol ratio of H2O2:Fe2+ was 210:1) than that of non-oxidized soil. Removal efficiency of tank oil was up to 93% after four weeks. Especially, the oil fraction (C10-C40) became more biodagradable after graded MF oxidation than its absence. Therefore, graded MF oxidation is a mild pretreatment to achieve an effective bioremediation of oil contaminated soil.

Fate of effluent-borne contaminants beneath septic tank drainfields overlying a Karst aquifer.

Science.gov (United States)

Katz, Brian G; Griffin, Dale W; McMahon, Peter B; Harden, Harmon S; Wade, Edgar; Hicks, Richard W; Chanton, Jeffrey P

2010-01-01

Groundwater quality effects from septic tanks were investigated in the Woodville Karst Plain, an area that contains numerous sinkholes and a thin veneer of sands and clays overlying the Upper Floridan aquifer (UFA). Concerns have emerged about elevated nitrate concentrations in the UFA, which is the source of water supply in this area of northern Florida. At three sites during dry and wet periods in 2007-2008, water samples were collected from the septic tank, shallow and deep lysimeters, and drainfield and background wells in the UFA and analyzed for multiple chemical indicators including nutrients, nitrate isotopes, organic wastewater compounds (OWCs), pharmaceutical compounds, and microbiological indicators (bacteria and viruses). Median NO3-N concentration in groundwater beneath the septic tank drainfields was 20 mg L(-1) (8.0-26 mg L(-1)). After adjusting for dilution, about 25 to 40% N loss (from denitrification, ammonium sorption, and ammonia volatilization) occurs as septic tank effluent moves through the unsaturated zone to the water table. Nitrogen loading rates to groundwater were highly variable at each site (3.9-12 kg N yr(-1)), as were N and chloride depth profiles in the unsaturated zone. Most OWCs and pharmaceutical compounds were highly attenuated beneath the drainfields; however, five Cs (caffeine, 1,7-dimethylxanthine, phenol, galaxolide, and tris(dichloroisotopropyl)phosphate) and two pharmaceutical compounds (acetaminophen and sulfamethoxazole) were detected in groundwater samples. Indicator bacteria and human enteric viruses were detected in septic tank effluent samples but only intermittently in soil water and groundwater. Contaminant movement to groundwater beneath each septic tank system also was related to water use and differences in lithology at each site.

Seismic response of elevated rectangular water tanks considering soil structure interaction

Science.gov (United States)

Visuvasam, J.; Simon, J.; Packiaraj, J. S.; Agarwal, R.; Goyal, L.; Dhingra, V.

2017-11-01

The overhead staged water tanks are susceptible for high lateral forces during earthquakes. Due to which, the failure of beam-columns joints, framing elements and toppling of tanks arise. To avoid such failures, they are analyzed and designed for lateral forced induced by devastating earthquakes assuming the base of the structures are fixed and considering functional needs, response reduction, soil types and severity of ground shaking. In this paper, the flexible base was provided as spring stiffness in order to consider the effect of soil properties on the seismic behaviour of water tanks. A linear time history earthquake analysis was performed using SAP2000. Parametric studies have been carried out based on various types of soils such as soft, medium and hard. The soil stiffness values highly influence the time period and base shear of the structure. The ratios of time period of flexible to fixed base and base shear of flexible to fixed base were observed against capacities of water tank and the overall height of the system. The both responses are found to be increased as the flexibility of soil medium decreases

Countercurrent soil washing system for remediation of viscous hydrocarbons, heavy metals, radionuclides

International Nuclear Information System (INIS)

Kuhlman, M.I.; Karlsson, M.K.; Downie, C.A.

1995-01-01

Drying augers and multicell DAF tanks are excellent machines in which to countercurrently wash soil and remove hazardous hydrocarbons, metals or radionuclides. An auger works well because it preferentially moves soil along one side of its trough. Thus, when enough high pressure and temperature water jets are placed along that path, contaminants can be melted, or dissolved and scoured from the soil. Contaminants and fines flow down the opposite side of the auger and out for extraction in a series of flotation tanks. Countercurrent washing of the silt results when soil settles in tanks through rising water and air bubbles then is pumped through cyclones placed above the next DAF tank of the series. LNAPLs, DNAPLs, or metallic contaminants made hydrophobic by chemicals in the system are removed at the overflow of the cyclones or by flotation in the tanks. The overflow from the cyclones and DAF tanks flows into the previous tank of the series. Examples of contaminants remediated include; arsenic, cadmium, lead and mercury, Naturally Occurring Radioactive Materials (NORM), uranium, solid oils, polyaromatic hydrocarbons in creosote and coal tars, and polychlorinated hydrocarbons

Photogrammetry Measurements During a Tanking Test on the Space Shuttle External Tank, ET-137

Science.gov (United States)

Littell, Justin D.; Schmidt, Tim; Tyson, John; Oliver, Stanley T.; Melis, Matthew E.; Ruggeri, Charles

2012-01-01

On November 5, 2010, a significant foam liberation threat was observed as the Space Shuttle STS-133 launch effort was scrubbed because of a hydrogen leak at the ground umbilical carrier plate. Further investigation revealed the presence of multiple cracks at the tops of stringers in the intertank region of the Space Shuttle External Tank. As part of an instrumented tanking test conducted on December 17, 2010, a three dimensional digital image correlation photogrammetry system was used to measure radial deflections and overall deformations of a section of the intertank region. This paper will describe the experimental challenges that were overcome in order to implement the photogrammetry measurements for the tanking test in support of STS-133. The technique consisted of configuring and installing two pairs of custom stereo camera bars containing calibrated cameras on the 215-ft level of the fixed service structure of Launch Pad 39-A. The cameras were remotely operated from the Launch Control Center 3.5 miles away during the 8 hour duration test, which began before sunrise and lasted through sunset. The complete deformation time history was successfully computed from the acquired images and would prove to play a crucial role in the computer modeling validation efforts supporting the successful completion of the root cause analysis of the cracked stringer problem by the Space Shuttle Program. The resulting data generated included full field fringe plots, data extraction time history analysis, section line spatial analyses and differential stringer peak ]valley motion. Some of the sample results are included with discussion. The resulting data showed that new stringer crack formation did not occur for the panel examined, and that large amounts of displacement in the external tank occurred because of the loads derived from its filling. The measurements acquired were also used to validate computer modeling efforts completed by NASA Marshall Space Flight Center (MSFC).

Impacts of external convection on release rates in metal hydride storage tanks. Paper no. IGEC-1-080

International Nuclear Information System (INIS)

MacDonald, B.; Rowe, A.; Tomlinson, J.; Ho, J.

2005-01-01

Reversible metal hydrides can be used to store hydrogen at relatively low pressures, with very high volumetric density. The rate hydrogen can be drawn from a given tank is strongly influenced by the rate heat can be transferred to the reaction zone. Because of this, enhancing and controlling heat transfer is a key area of research in the development of metal hydride storage tanks. In this work, the impacts of external convection resistance on hydrogen release rates are examined. A one-dimensional resistive analysis determines the thermal resistances in the system based on one case where no external heat transfer enhancements are used, and a second case where external fins are used. A two-dimensional, transient model, developed in FEMLAB, is used to determine the impact of the external fins on the mass flow rate of hydrogen in more detail. For the particular metal hydride alloy (LaNi 4.8 Sn 0.2 ) and tank geometry studied, it was found that the fins have a large impact on the hydrogen flow rate during the initial stages of desorption. The flow rate with no fins is only 20% of the flow rate with fins for a full tank, 57% when the tank is 33% full, and 74% when the tank is 5% full. As the reaction proceeds, the resistance of the metal hydride alloy within the tank increases and becomes dominant. Therefore, the impact of the fins becomes less significant as the tank empties. (author)

Phytoremediation of Soils Contaminated by Chlorinnated Hydrocarbons

Science.gov (United States)

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

2001-12-01

In recent years, the possible use of deep rooted plants for phytoremediation of soil contaminants has been offered as a potential alternative for waste management, particularly for in situ remediation of large volumes of contaminated soils. Major objectives of this study are to evaluate the effectiveness of a warm season grass (Eastern Gamagrass) and a cool season prairie grass (Annual Ryegrass) in the phytoremediation of the soil contaminated with volatile organic compounds e.g., trichloroethylene (TCE), tetrachloroethylene (PCE), and 1,1,1-trichloroethane (TCA) and to determine the main mechanisms of target contaminant dissipation. The preliminary tests and laboratory scale tests were conducted to identify the main mechanisms for phytoremediation of the target contaminants, and to apply the technique in green house application under field conditions. The results of microcosm and bioreactor experiments showed that volatilization can be the dominant pathway of the target contaminant mass losses in soils. Toxicity tests, conducted in nutrient solution in the growth room, and in the greenhouse, showed that both Eastern gamagrass and Annual ryegrass could grow without harmful effects at up to 400 ppm each of all three contaminants together. Preliminary greenhouse experimentw were conducted with the 1.5 m long and 0.3 m diameter PVC columns. Soil gas concentrations monitored and microbial biomass in bulk and rhizosphere soil, root properties, and contaminant concentration in soil after 100 days were analyzed. The results showed that the soil gas concentration of contaminants has rapidly decreased especially in the upper soil and the contaminant concentraitons in soil were also significantly decreased to 0.024, 0.228, and 0.002 of C/Co for TCE, PCE and TCA, respectively. Significant plant effects were not found however showed contaminant loss through volatilization and plant contamination by air.

Analysis of ICPP tank farm infiltration

International Nuclear Information System (INIS)

Richards, B.T.

1993-10-01

This report addresses water seeping into underground vaults which contain high-level liquid waste (HLLW) storage tanks at the Idaho Chemical Processing Plant (ICPP). Each of the vaults contains from one to three sumps. The original purpose of the sumps was to serve as a backup leak detection system for release of HLLW from the storage tanks. However, water seeps into most of the vaults, filling the sumps, and defeating their purpose as a leak detection system. Leak detection for the HLLW storage tanks is based on measuring the level of liquid inside the tank. The source of water leaking into the vaults was raised as a concern by the State of Idaho INEL Oversight Group because this source could also be leaching contaminants released to soil in the vicinity of the tank farm and transporting contaminants to the aquifer. This report evaluates information concerning patterns of seepage into vault sumps, the chemistry of water in sumps, and water balances for the tank farm to determine the sources of water seeping into the vaults

Airborne exposure and soil levels associated with lead abatement of a steel tank.

Science.gov (United States)

Lange, John H

2002-02-01

This study reports on airborne exposure levels and soil concentrations of lead in regard to abatement of a steel structure (water tank). The tank was de-leaded by abrasive sand blasting. The ball of the tank had a lead surface level that exceeded the Environmental Protection Agency (EPA) definition of lead-based paint (LBP) (0.5% lead), but paint on stem and base was below this criterion. Personal and area airborne samples were collected during different activities of lead abatement of the tank. Summary results suggest during abrasive blasting of ball and stem/base personal exposure levels, as reported with arithmetic and geometric means, exceed the Occupational Safety and Health Administration (OSHA) permissible exposure limit (50 microg/m3). Highest personal exposure (occupational exposure) was associated with blasting of ball. Distribution of airborne and soil samples suggest non-normality and is best represented by a logarithmic form. Geometric standard deviations for air and soil lead support a non-normal distribution. Outlying values were found for personal and area air samples. Exposure levels associated with blasting stem/base section of tank support OSHA's policy requiring air monitoring of work at levels below the criterion established by EPA in identifying LBP. Area samples were statistically lower than personal samples associated with blasting ball and stem/base of tank. Exposure data suggest that workers performing abatement on steel structures have elevated lead exposure from surface lead. Respirator protection requirements are discussed. Soil lead concentration was suggested to decrease as distance increased from tank. Soil lead is suggested to be a result of deposition from LBP on tank surface. Minimal efforts were required to reduce average lead soil levels below EPA's upper acceptable criterion (1200 ppm Pb).

Contaminant Release from Residual Waste in Single Shell Tanks at the Hanford Site, Washington, USA - 9276

International Nuclear Information System (INIS)

Cantrell, Kirk J.; Krupka, Kenneth M.; Deutsch, William J.; Lindberg, Michael J.

2009-01-01

Determinations of elemental and solid-phase compositions, and contaminant release studies have been applied in an ongoing study of residual tank wastes (i.e., waste remaining after final retrieval operations) from five of 149 underground single-shell storage tanks (241-C-103, 241-C-106, 241-C-202, 241-C-203, and 241-S-112) at the U.S. Department of Energy's Hanford Site in Washington State. This work is being conducted to support performance assessments that will be required to evaluate long-term health and safety risks associated with tank site closure. The results of studies completed to date show significant variability in the compositions, solid phase properties, and contaminant release characteristics from these residual tank wastes. This variability is the result of differences in waste chemistry/composition of wastes produced from several different spent fuel reprocessing schemes, subsequent waste reprocessing to remove certain target constituents, tank farm operations that concentrated wastes and mixed wastes between tanks, and differences in retrieval processes used to remove the wastes from the tanks. Release models were developed based upon results of chemical characterization of the bulk residual waste, solid-phase characterization (see companion paper 9277 by Krupka et al.), leaching and extraction experiments, and geochemical modeling. In most cases empirical release models were required to describe contaminant release from these wastes. Release of contaminants from residual waste was frequently found to be controlled by the solubility of phases that could not be identified and/or for which thermodynamic data and/or dissolution rates have not been measured. For example, significant fractions of Tc-99, I-129, and Cr appear to be coprecipitated at trace concentrations in metal oxide phases that could not be identified unambiguously. In the case of U release from tank 241-C-103 residual waste, geochemical calculations indicated that leachate

Remediation of lead-contaminated soils

International Nuclear Information System (INIS)

Peters, R.W.; Shem, L.

1992-01-01

Excavation and transport of soil contaminated with heavy metals has generally been the standard remediation technique for treatment of heavy-metal-contaminated soils. This approach is not a permanent solution; moreover, off-site shipment and disposal of contaminated soil involves high expense, liability, and appropriate regulatory approval. Recently, a number of other techniques have been investigated for treating such contaminated sites, including flotation, solidification/stabilization, vitrification, and chemical extraction. This paper reports the results of a laboratory investigation determining the efficiency of using chelating agents to extract lead from contaminated soils. Lead concentrations in the soils ranged from 500 to 10,000 mg/kg. Ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) were examined for their potential extractive capabilities. Concentrations of the chelating agents ranged from 0.01 to 0.10 M. The pH of the suspensions in which the extractions were performed ranged from 4 to 12. Results showed that the removal of lead using NTA and water was ph-dependent, whereas the removal of lead using EDTA was ph-insensitive. Maximum removals of lead were 68.7%,19.1%, and 7.3% using EDTA, NTA, and water, respectively (as compared with initial lead concentrations)

Assessment of vadose zone radionuclide contamination around Single Shell Tank 241-C-103

International Nuclear Information System (INIS)

Kos, S.E.

1995-12-01

Five drywells surrounding single shell tank 241-C-103 were logged with the high-purity germanium logging system to investigate possible leakage of radioactive contamination from the tank. The investigation included integration of the drywell survey results with several other data sources. There is no conclusive evidence showing indications that the 241-C-103 tank has leaked

Soil-structure interaction effects on high level waste tanks

International Nuclear Information System (INIS)

Miller, C.A.; Costantino, C.J.; Heymsfeld, E.

1991-01-01

High Level Waste Tanks consist of steel tanks located in concrete vaults which are usually completely embedded in the soil. Many of these tanks are old and were designed to seismic standards which are not compatible with current requirements. The objective if this paper is to develop simple methods of modeling SSI effects for such structures and to obtain solutions for a range of parameters that can be used to identify significant aspects of the problem

Manufacturing Challenges Implementing Material Changes for the Super Light Weight External Tank: A Welding Process Perspective

Science.gov (United States)

Lawless, K.; Jones, C.

2001-01-01

A viewgraph presentation gives an overview of the manufacturing challenges in implementing welding material changes for the super lightweight external tank. Details are given on the external tank configuration, the weld purging equipment used, planning the selection of weld filler wire alloy, the initial weld microstructure, the wide panel tensile testing, and the dome cap welding.

Uranium-contaminated soil pilot treatment study

International Nuclear Information System (INIS)

Turney, W.R.J.R.; Mason, C.F.V.; Michelotti, R.A.

1996-01-01

A pilot treatment study is proving to be effective for the remediation of uranium-contaminated soil from a site at the Los Alamos National Laboratory by use of a two-step, zero-discharge, 100% recycle system. Candidate uranium-contaminated soils were characterized for uranium content, uranium speciation, organic content, size fractionization, and pH. Geochemical computer codes were used to forecast possible uranium leach scenarios. Uranium contamination was not homogenous throughout the soil. In the first step, following excavation, the soil was sorted by use of the ThemoNuclean Services segmented gate system. Following the sorting, uranium-contaminated soil was remediated in a containerized vat leach process by use of sodium-bicarbonate leach solution. Leach solution containing uranium-carbonate complexes is to be treated by use of ion-exchange media and then recycled. Following the treatment process the ion exchange media will be disposed of in an approved low-level radioactive landfill. It is anticipated that treated soils will meet Department of Energy site closure guidelines, and will be given open-quotes no further actionclose quotes status. Treated soils are to be returned to the excavation site. A volume reduction of contaminated soils will successfully be achieved by the treatment process. Cost of the treatment (per cubic meter) is comparable or less than other current popular methods of uranium-contamination remediation

SOILD: A computer model for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil

International Nuclear Information System (INIS)

Chen, S.Y.; LePoire, D.; Yu, C.; Schafetz, S.; Mehta, P.

1991-01-01

The SOLID computer model was developed for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil. It is designed to assess external doses under various exposure scenarios that may be encountered in environmental restoration programs. The models four major functional features address (1) dose versus source depth in soil, (2) shielding of clean cover soil, (3) area of contamination, and (4) nonuniform distribution of sources. The model is also capable of adjusting doses when there are variations in soil densities for both source and cover soils. The model is supported by a data base of approximately 500 radionuclides. 4 refs

Phytoextraction of low level U-contaminated soil

International Nuclear Information System (INIS)

Vandenhove, H.A.; Hees, M. van

2002-01-01

The nuclear fuel cycle may be a source of environmental contamination. Uranium exploitation produces large quantities of wastes but also accidental spills at nuclear fuel production, reprocessing or waste treatment plants have led to soil contamination with uranium. U-contaminated soil is generally excavated, packaged and removed which is a costly enterprise. Soil washing has also shown promising in removing U from contaminated soil, but results in the generation of liquid wastes and the deterioration of soil properties. In contrast, phytoextraction, the use of plants to remove contaminants from polluted soil, allows for in situ treatment and does not generate liquid wastes. Furthermore, the contaminated site is covered by plants during phytoextraction and wind and water erosion will be reduced. The phytoextraction potential depends on the amount of radionuclides extracted and the biomass produced. Hyper-accumulating plants often have a low biomass production. Moreover, uranium soil-to-plant transfer factors (TF: ratio of U concentration in dry plant tissue to concentration in soil) rarely exceed a value of 0.1 gg -1 . With a TF of 0.1 gg -1 and a biomass yield of 15t dry weigh ha -1 only 0.1% of the soil uranium will be annually immobilised in the plant biomass. These figures clearly show that the phytoextraction option is not a feasible remediation option, unless the uranium bioavailability could be drastically increased. It was shown that citric acid addition to highly contaminated U contaminated soil increased the U-accumulation of Brassica juncea 1000-fold. The objective of the present paper is to find out if low level U contaminated soil can be phytoextracted in order to achieve proposed release limits

Desorption and bioremediation of hydrocarbon contaminated soils

International Nuclear Information System (INIS)

Gray, M.R.

1998-01-01

A study was conducted in which the extent and pattern of contaminant biodegradation during bioremediation of four industrially-contaminated soils were examined to determine which factors control the ultimate extent of biodegradation and which limit the success of biological treatment. It was noted that although bioremediation is inexpensive and has low environmental impact, it often fails to completely remove the hydrocarbons in soils because of the complex interactions between contaminants, the soil environment, and the active microorganisms. In this study, the competency of the microorganisms in the soil to degrade the contaminants was examined. The equilibrium partitioning of the contaminants between the soil and the aqueous phase was also examined along with the transport of contaminants out of soil particles. The role of diffusion of compounds in the soil and the importance of direct contact between microorganisms and the hydrocarbons was determined. Methods for selecting suitable sites for biological treatment were also described

Effects of soil water content on the external exposure of fauna to radioactive isotopes.

Science.gov (United States)

Beaugelin-Seiller, K

2016-01-01

Within a recent model intercomparison about radiological risk assessment for contaminated wetlands, the influence of soil saturation conditions on external dose rates was evidenced. This issue joined concerns of assessors regarding the choice of the soil moisture value to input in radiological assessment tools such as the ERICA Tool. Does it really influence the assessment results and how? This question was investigated under IAEA's Modelling and Data for Radiological Impacts Assessments (MODARIA) programme via 42 scenarios for which the soil water content varied from 0 (dry soil) to 100% (saturated soil), in combination with other parameters that may influence the values of the external dose conversion coefficients (DCCs) calculated for terrestrial organisms exposed in soil. A set of α, β, and γ emitters was selected in order to cover the range of possible emission energies. The values of their external DCCs varied generally within a factor 1 to 1.5 with the soil water content, excepted for β emitters that appeared more sensitive (DCCs within a factor of about 3). This may be of importance for some specific cases or for upper tiers of radiological assessments, when refinement is required. But for the general purpose of screening assessment of radiological impact on fauna and flora, current approaches regarding the soil water content are relevant. Copyright © 2015 Elsevier Ltd. All rights reserved.

Application of the biological forced air soil treatment (BIOFAST trademark) technology to diesel contaminated soil

International Nuclear Information System (INIS)

Lyons, K.A.; Leavitt, M.E.; Graves, D.A.; Stanish, S.M.

1993-01-01

A subsurface Biological Forced Air Soil Treatment (BIOFAST trademark) system was constructed at the Yellow Freight System, Inc. (Yellow Freight) New Haven facility in Connecticut as a means of expediting the remediation of soils impacted by a diesel fuel release. Prior to beginning construction activities the soils were evaluated for the feasibility of bioremediation based on soil characteristics including contaminant degrading bacteria, moisture content, and pH. Based on results of stimulant tests with oxygen and nutrients, the addition of fertilizer during the construction of the cell was recommended. Following the removal of underground storage tanks, the bioremediation cell was constructed by lining the enlarged excavation with high density polyethylene (HDPE) and backfilling alternating layers of nutrient-laden soil and pea gravel. Passive and active soil vapor extraction (SVE) piping was included in the gravel layers and connected to a blower and vapor treatment unit, operated intermittently to supply oxygen to the subsurface cell. Operating data have indicated that the bacteria are generating elevated levels of CO 2 , and the SVE unit is evacuating the accumulated CO 2 from the soils and replacing it with fresh air. These data suggest that the bioremediation process is active in the soils. Soil samples collected from within the soil pit subsequent to installation and again after 10 months of operation indicate that TPH concentrations have decreased by as much as 50%

In situ stabilization of mixed radioactive waste storage tanks and contaminated soil areas

International Nuclear Information System (INIS)

Matthern, G.E.; Meservey, R.H.

1997-01-01

Within the Department of Energy (DOE) Complex, there are a number of small (<50,000 gallons) underground Storage tanks containing mixed waste materials. The radioactive content of wastes eliminates the feasibility for hazardous waste treatment in accordance with previously prescribed Resource Conservation and Recovery Act (RCRA) technologies. As a result, DOE is funding in situ stabilization technology development for these tanks, Some of this development work has been done at the Idaho National Engineering and Environmental Laboratory (INEEL) and the initial efforts there were concentrated on the stabilization of the contents of the Test Area North (TAN) V-9 Tank. This is a 400 gallon underground tank filled with about 320 gallons of liquids and silty sediments. Sampling data indicates that approximately 50 wt% of the tank contents is aqueous-phase liquids. The vertically oriented cylindrical tank has a conical bottom and a chordal baffle that separates the tank inlet from its outlet. Access to the tank is through a six inch diameter access pipe on top of the tank. Because of the high volume, and the high concentration of aqueous-phase materials, Tank V-9 stabilization efforts have focussed on applying in situ agitation with dry feed addition to stabilize its contents. Materials selected for dry feed addition to this tank include a mixture of Aquaset IIH, and Type I/II Portland cement. This paper describes the results of proof-of-concept tests performed on full scale mockups of the Tank V-9. This proof-of-concept test were used to set operating parameters for in situ mixing, as well as evaluate how variations in Aquaset IIH/Portland cement ratio and sediment to liquid volume affected mixing of the tank

Soil washing and post-wash biological treatment of petroleum hydrocarbon contaminated soils

OpenAIRE

Bhandari, Alok

1992-01-01

A laboratory scale study was conducted to investigate the treatability of petroleum contaminated soils by soil washing and subsequent biological treatment of the different soil fractions. In addition to soils obtained from contaminated sites, studies were also performed on soils contaminated in the laboratory. Soil washing was performed using a bench-scale soil washing system. Washing was carried out with simultaneous fractionation of the bulk soil into sand, silt and clay fractions. Cl...

IMPACT ASSESSMENT OF EXISTING VADOSE ZONE CONTAMINATION AT THE HANFORD SITE SX TANK FARM

International Nuclear Information System (INIS)

KHALEEL R

2007-01-01

The USDOE has initiated an impact assessment of existing vadose zone contamination at the Hanford Site SX tank farm in southeastern Washington State. The assessment followed the Resource Conservation and Recovery Act (RCRA) Corrective Action process to address the impacts of past tank waste releases to the vadose zone at the single-shell tank farm. Numerical models were developed that consider the extent of contamination presently within the vadose zone and predict contaminant movement through the vadose zone to groundwater. The transport of representative mobile (technetium-99) and immobile (cesium-137) constituents was evaluated in modeling. The model considered the accelerated movement of moisture around and beneath single-shell tanks that is attributed to bare, gravel surfaces resulting from the construction of the underground storage tanks. Infiltration, possibly nearing 100 mm yr -1 , is further amplified in the tank farm because of the umbrella effect created by percolating moisture being diverted by the impermeable, sloping surface of the large, 24-m-diameter, buried tank domes. For both the base case (no-action alternative) simulation and a simulation that considered placement of an interim surface barrier to minimize infiltration, predicted, groundwater concentrations for technetium-99 at the SX tank farm boundary were exceedingly high, on the order of 10 6 pCi L -1 . The predicted concentrations are, however, somewhat conservative because of our use of two-dimensional modeling for a three-dimensional problem. A series of simulations were performed, using recharge rates of 50, 30, and 10 mm yr -1 , and compared to the basecase(100 mm yr -1 ) results. As expected, lowering meteoric recharge delayed peak arrival times and reduced peak concentrations at the tank farm boundary

Impact Assessment of Existing Vadose Zone Contamination at the Hanford Site SX Tank Farm

International Nuclear Information System (INIS)

Khaleel, Raziuddin; White, Mark D.; Oostrom, Martinus; Wood, Marcus I.; Mann, Frederick M.; Kristofzski, John G.

2007-01-01

The USDOE has initiated an impact assessment of existing vadose zone contamination at the Hanford Site SX tank farm in southeastern Washington State. The assessment followed the Resource Conservation and Recovery Act (RCRA) Corrective Action process to address the impacts of past tank waste releases to the vadose zone at the single-shell tank farm. Numerical models were developed that consider the extent of contamination presently within the vadose zone and predict contaminant movement through the vadose zone to groundwater. The transport of representative mobile (technetium-99) and immobile (cesium-137) constituents was evaluated in modeling. The model considered the accelerated movement of moisture around and beneath single-shell tanks that is attributed to bare, gravel surfaces resulting from the construction of the underground storage tanks. Infiltration, possibly nearing 100 mm yr -1 , is further amplified in the tank farm because of the umbrella effect created by percolating moisture being diverted by the impermeable, sloping surface of the large, 24-m-diameter, buried tank domes. For both the base case (no-action alternative) simulation and a simulation that considered placement of an interim surface barrier to minimize infiltration, predicted groundwater concentrations for technetium-99 at the SX tank farm boundary were exceedingly high, on the order of 106 pCi L-1. The predicted concentrations are, however, somewhat conservative because of our use of two-dimensional modeling for a three-dimensional problem. A series of simulations were performed, using recharge rates of 50, 30, and 10 mm yr -1 , and compared to the base case (100 mm yr -1 ) results. As expected, lowering meteoric recharge delayed peak arrival times and reduced peak concentrations at the tank farm boundary.

External Contamination Control of Attached Payloads on the International Space Station

Science.gov (United States)

Soares, Carlos E.; Mikatarian, Ronald R.; Olsen, Randy L.; Huang, Alvin Y.; Steagall, Courtney A.; Schmidl, William D.; Wright, Bruce D.; Koontz, Steven

2012-01-01

The International Space Station (ISS) is an on-orbit platform for science utilization in low Earth orbit with multiple sites for external payloads with exposure to the natural and induced environments. Contamination is one of the induced environments that can impact performance, mission success and science utilization on the vehicle. This paper describes the external contamination control requirements and integration process for externally mounted payloads on the ISS. The external contamination control requirements are summarized and a description of the integration and verification process is detailed to guide payload developers in the certification process of attached payloads on the vehicle. A description of the required data certification deliverables covers the characterization of contamination sources. Such characterization includes identification, usage and operational data for each class of contamination source. Classes of external contamination sources covered are vacuum exposed materials, sources of leakage, vacuum venting and thrusters. ISS system level analyses are conducted by the ISS Space Environments Team to certify compliance with external contamination control requirements. This paper also addresses the ISS induced contamination environment at attached payload sites, both at the requirements level as well as measurements made on ISS.

DEEP VADOSE ZONE CONTAMINATION DUE TO RELEASES FROM HANFORD SITE TANKS

International Nuclear Information System (INIS)

JARAYSI MN

2008-01-01

CH2M HILL Hanford Group, Inc. (the Hanford Tank Farm Operations contractor) and the Department of Energy's Office of River Protection have just completed the first phase of the Hanford Single-Shell Tank RCRA Corrective Action Program. The focus of this first phase was to characterize the nature and extent of past Hanford single-shell tank releases and to characterize the resulting fate and transport of the released contaminants. Most of these plumes are below 20 meters, with some reaching groundwater (at 60 to 120 meters below ground surface [bgs])

Chemical fingerprinting of hydrocarbon-contamination in soil

DEFF Research Database (Denmark)

Boll, Esther Sørensen; Nejrup, Jens; Jensen, Julie K.

2015-01-01

Chemical fingerprinting analyses of 29 hydrocarbon-contaminated soils were performed to assess the soil quality and determine the main contaminant sources. The results were compared to an assessment based on concentrations of the 16 priority polycyclic aromatic hydrocarbons pointed out by the U...... and in assessing weathering trends of hydrocarbon contamination in the soils. Multivariate data analysis of sum-normalized concentrations could as a stand-alone tool distinguish between hydrocarbon sources of petrogenic and pyrogenic origin, differentiate within petrogenic sources, and detect weathering trends....... Diagnostic ratios of PACs were not successful for source identification of the heavily weathered hydrocarbon sources in the soils. The fingerprinting of contaminated soils revealed an underestimation of PACs in petrogenic contaminated soils when the assessment was based solely on EPAPAH16. As alkyl...

Bioremediation of petroleum contaminated soil

International Nuclear Information System (INIS)

Autry, A.R.; Ellis, G.M.

1992-01-01

This paper reports on bioremediation, which offers a cost-competitive, effective remediation alternative for soil contaminated with petroleum products. These technologies involve using microorganisms to biologically degrade organic constituents in contaminated soil. All bioremediation applications must mitigate various environmental rate limiting factors so that the biodegradation rates for petroleum hydrocarbons are optimized in field-relevant situations. Traditional bioremediation applications include landfarming, bioreactors, and composting. A more recent bioremediation application that has proven successful involves excavation of contaminated soil. The process involves the placement of the soils into a powerscreen, where it is screened to remove rocks and larger debris. The screened soil is then conveyed to a ribbon blender, where it is mixed in batch with nutrient solution containing nitrogen, phosphorus, water, and surfactants. Each mixed soil batch is then placed in a curing pile, where it remains undisturbed for the remainder of the treatment process, during which time biodegradation by naturally occurring microorganisms, utilizing biochemical pathways mediated by enzymes, will occur

Polymers for subterranean containment barriers for underground storage tanks (USTs)

International Nuclear Information System (INIS)

Heiser, J.H.; Colombo, P.; Clinton, J.

1992-12-01

The US Department of Energy (DOE) set up the Underground Storage Tank Integrated Demonstration Program (USTID) to demonstrate technologies for the retrieval and treatment of tank waste, and closure of underground storage tanks (USTs). There are more than 250 underground storage tanks throughout the DOE complex. These tanks contain a wide variety of wastes including high level, low level, transuranic, mixed and hazardous wastes. Many of the tanks have performed beyond the designed lifetime resulting in leakage and contamination of the local geologic media and groundwater. To mitigate this problem it has been proposed that an interim subterranean containment barrier be placed around the tanks. This would minimize or prevent future contamination of soil and groundwater in the event that further tank leakages occur before or during remediation. Use of interim subterranean barriers can also provide sufficient time to evaluate and select appropriate remediation alternatives. The DOE Hanford site was chosen as the demonstration site for containment barrier technologies. A panel of experts for the USTID was convened in February, 1992, to identify technologies for placement of subterranean barriers. The selection was based on the ability of candidate grouts to withstand high radiation doses, high temperatures and aggressive tank waste leachates. The group identified and ranked nine grouting technologies that have potential to place vertical barriers and five for horizontal barriers around the tank. The panel also endorsed placement technologies that require minimal excavation of soil surrounding the tanks

SEPTIC TANK SETBACK DISTANCES: A WAY TO MINIMIZE VIRUS CONTAMINATION OF DRINKING WATER

Science.gov (United States)

Septic tanks are the most frequently reported causes of contamination in ground-water disease outbreaks associated with the consumption of untreated ground water in the United States. The placement of septic tanks is generally controlled by county-wide or state-wide regulations, ...

CONTAMINATED SOIL VOLUME ESTIMATE TRACKING METHODOLOGY

International Nuclear Information System (INIS)

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

2003-01-01

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

Bench Scale Treatability Studies of Contaminated Soil Using Soil Washing Technique

OpenAIRE

Gupta, M. K.; Srivastava, R. K.; Singh, A. K.

2010-01-01

Soil contamination is one of the most widespread and serious environmental problems confronting both the industrialized as well as developing nations like India. Different contaminants have different physicochemical properties, which influence the geochemical reactions induced in the soils and may bring about changes in their engineering and environmental behaviour. Several technologies exist for the remediation of contaminated soil and water. In the present study soil washing technique using...

The use of aluminum dome tank roofs

International Nuclear Information System (INIS)

Morovich, G.L.

1992-01-01

Since the late 1970's the aluminum dome tank roof has gained wide usage for both new and retrofit applications. The increased application for the structure results from a need for maintenance reduction, environmental considerations, concern for product quality and economics. The American Petroleum Institute (API) has approved Standard API 650, Appendix G - Structurally Supported Aluminum Dome Roofs for publication. The aluminum dome was originally used as weather cover for retrofiting external floating roof tanks. The roof was considered for the reduction of maintenance related to draining water from the external floating roofs and problems resulting from freezing of drain lines and snow accumulation. This paper reports that environmental concerns have expanded the value of aluminum dome roofs. Rainwater bypassing the seals of an external floating roof became classified as a hazardous material requiring special and expensive disposal procedures. The marketing terminal facilities typically do not have the capacity for proper treatment of contaminated bottom water. With new fuel additives being water soluble, water contamination not only created a hazardous waste disposal problem, but resulted in reduced product quality

Hanford tank residual waste - Contaminant source terms and release models

International Nuclear Information System (INIS)

Deutsch, William J.; Cantrell, Kirk J.; Krupka, Kenneth M.; Lindberg, Michael L.; Jeffery Serne, R.

2011-01-01

Highlights: → Residual waste from five Hanford spent fuel process storage tanks was evaluated. → Gibbsite is a common mineral in tanks with high Al concentrations. → Non-crystalline U-Na-C-O-P ± H phases are common in the U-rich residual. → Iron oxides/hydroxides have been identified in all residual waste samples. → Uranium release is highly dependent on waste and leachant compositions. - Abstract: Residual waste is expected to be left in 177 underground storage tanks after closure at the US Department of Energy's Hanford Site in Washington State, USA. In the long term, the residual wastes may represent a potential source of contamination to the subsurface environment. Residual materials that cannot be completely removed during the tank closure process are being studied to identify and characterize the solid phases and estimate the release of contaminants from these solids to water that might enter the closed tanks in the future. As of the end of 2009, residual waste from five tanks has been evaluated. Residual wastes from adjacent tanks C-202 and C-203 have high U concentrations of 24 and 59 wt.%, respectively, while residual wastes from nearby tanks C-103 and C-106 have low U concentrations of 0.4 and 0.03 wt.%, respectively. Aluminum concentrations are high (8.2-29.1 wt.%) in some tanks (C-103, C-106, and S-112) and relatively low ( 2 -saturated solution, or a CaCO 3 -saturated water. Uranium release concentrations are highly dependent on waste and leachant compositions with dissolved U concentrations one or two orders of magnitude higher in the tests with high U residual wastes, and also higher when leached with the CaCO 3 -saturated solution than with the Ca(OH) 2 -saturated solution. Technetium leachability is not as strongly dependent on the concentration of Tc in the waste, and it appears to be slightly more leachable by the Ca(OH) 2 -saturated solution than by the CaCO 3 -saturated solution. In general, Tc is much less leachable (<10 wt.% of the

ISS External Contamination Environment for Space Science Utilization

Science.gov (United States)

Soares, Carlos; Mikatarian, Ron; Steagall, Courtney; Huang, Alvin; Koontz, Steven; Worthy, Erica

2014-01-01

(1) The International Space Station is the largest and most complex on-orbit platform for space science utilization in low Earth orbit, (2) Multiple sites for external payloads, with exposure to the associated natural and induced environments, are available to support a variety of space science utilization objectives, (3) Contamination is one of the induced environments that can impact performance, mission success and science utilization on the vehicle, and (4)The ISS has been designed, built and integrated with strict contamination requirements to provide low levels of induced contamination on external payload assets.

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

Science.gov (United States)

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

2009-01-01

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.

Assessment of ground-water contamination from a leaking underground storage tank at a defense supply center near Richmond, Virginia

International Nuclear Information System (INIS)

Powell, J.D.; Wright, W.G.

1990-01-01

During 1988-89, 24 wells were installed in the vicinity of the post-exchange gasoline station on the Defense General Supply Center, near Richmond, Virginia, to collect and analyze groundwater samples for the presence of gasoline contamination from a leaking underground storage tank. Concentrations of total petroleum hydrocarbons and benzene were as high as 8.2 mg/L and 9,000 microg/L, respectively, in water from wells in the immediate vicinity of the former leaking tank, and benzene concentrations were as high as 2,300 microg/L in a well 600 ft down gradient from the gasoline station. Groundwater flow rate are estimated to be about 60 to 80 ft/yr; on the basis of these flow rates, the contaminants may have been introduced into the groundwater as long as 7-10 yrs ago. Groundwater might infiltrate a subsurface storm sewer, where the sewer is below the water table, and discharge into a nearby stream. Preliminary risk assessment for the site identified no potential human receptors to the groundwater contamination because there were no groundwater users identified in the area. Remediation might be appropriate if exposure of future potential users is concern. Alternatives discussed for remediation of groundwater contamination in the upper aquifer at the PX Service Station include no-action, soil vapor extraction, and groundwater pumping and treatment alternatives

Hanford Tank 241-C-106: Residual Waste Contaminant Release Model and Supporting Data

International Nuclear Information System (INIS)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Schaef, Herbert T.

2005-01-01

CH2M HILL is producing risk/performance assessments to support the closure of single-shell tanks at the DOE's Hanford Site. As part of this effort, staff at PNNL were asked to develop release models for contaminants of concern that are present in residual sludge remaining in tank 241-C-106 (C-106) after final retrieval of waste from the tank. This report provides the information developed by PNNL

Mass separation and risk assessment of commingled contamination in soil and ground water

Energy Technology Data Exchange (ETDEWEB)

Dai, Q.L.; Chau, T.S. [Alberta Environment, Red Deer, AB (Canada)

2008-07-01

Gasoline service stations in urban areas may be sources of groundwater pollution if petroleum hydrocarbons (PHCs) were to leak from underground storage tanks. Depending on the site-specific hydrogeologic conditions, the PHC could be retained in the soil, float on top of the groundwater table, dissolve in the groundwater or partition into soil vapour. This study focused on risk assessment and and management of soil and groundwater pollution caused by PHC releases from multiple sources which lead to commingling of subsurface plumes that require identification, assessment and control. Risk management decisions are made according to the different protection zones corresponding to different exposure pathways into which the commingled groundwater plume is divided, such as inhalation, ingestion and freshwater aquatic life. In order to effectively evaluate and manage commingled plumes, responsible parties must cooperate in sharing information on contaminated sites and developing joint programs for investigation, monitoring, remediation and risk management. This study proposed methodologies for determining mass contribution to a commingled plume from multiple contaminant sources. It was concluded that the levels of risk to human and environmental health can be determined by considering contaminant sources, migration pathways and potential receptors. Migration of PHCs in the subsurface is influenced by several uncertainties such as pollutant release and remediation histories, preferential pathways and hydrogeologic boundary conditions. Proper site characterization is necessary for reliable mass separation and to delineate contaminant plumes. Mathematical models can be used to simulate subsurface flow and transport processes. 5 refs., 4 figs.

Evaporation of petroleum products from contaminated soils

International Nuclear Information System (INIS)

Kang, S.H.

1996-01-01

Bioremediation can remove petroleum products from soil that has been contaminated by leaking underground storage tanks, but abiotic processes such as evaporation can contribute significantly to the overall removal process. The mathematical model described in this paper was developed to predict the evaporation rate of volatile liquids from petroleum-contaminated sand. The model is based on simple concepts relating to molecular diffusion embodied in the theory underlying the estimation of binary diffusivities using measurements made with an Arnold diffusion cell. The model in its simplified form indicates that the rate of evaporation for a particular volatile liquid is proportional to the square root of the product of diffusivity and partial pressure divided by the molecular weight of the liquid. This in part explains why evaporative losses from sand are so much higher for gasoline than for diesel fuel. The model also shows that the time for evaporation is directly proportional to the square of the depth dried out and inversely proportional to the vapor pressure of the volatile liquid. The model was tested using gravimetric measurements of the evaporation of n-heptane, unleaded gasoline, and diesel fuel from sand under laboratory conditions

Treatment of chromium contaminated soil using bioremediation

Science.gov (United States)

Purwanti, Ipung Fitri; Putri, Tesya Paramita; Kurniawan, Setyo Budi

2017-11-01

Chromium contamination in soil occurs due to the disposal of chromium industrial wastewater or sludge that excess the quality standard. Chromium concentration in soil is ranged between 1 to 300 mg/kg while the maximum health standard is 2.5 mg/kg. Bioremediation is one of technology that could be used for remediating heavy metal contamination in soil. Bacteria have an ability to remove heavy metal from soil. One bacteria species that capable to remove chromium from soil is Bacillus subtilis. The aim of this research was to know the chromium removal percentage in contaminated soil by Bacillus subtilis. Artificial chromium contaminated soil was used by mixing 425gram sand and chromium trichloride solution. Concentration of chromium added into the spiked soil were 50, 75, and 100 mg/L. During 14 days, pH, soil temperature and soil moisture were tested. Initial and final number of bacterial colony and chromium concentration analysed. The result showed that the highest percentage of chromium removal was 11% at a chromium concentration of 75 mg/L

The tolerance efficiency of Panicum maximum and Helianthus annuus in TNT-contaminated soil and nZVI-contaminated soil.

Science.gov (United States)

Jiamjitrpanich, Waraporn; Parkpian, Preeda; Polprasert, Chongrak; Laurent, François; Kosanlavit, Rachain

2012-01-01

This study was designed to compare the initial method for phytoremediation involving germination and transplantation. The study was also to determine the tolerance efficiency of Panicum maximum (Purple guinea grass) and Helianthus annuus (Sunflower) in TNT-contaminated soil and nZVI-contaminated soil. It was found that the transplantation of Panicum maximum and Helianthus annuus was more suitable than germination as the initiate method of nano-phytoremediation potting test. The study also showed that Panicum maximum was more tolerance than Helianthus annuus in TNT and nZVI-contaminated soil. Therefore, Panicum maximum in the transplantation method should be selected as a hyperaccumulated plant for nano-phytoremediation potting tests. Maximum tolerance dosage of Panicum maximum to TNT-concentration soil was 320 mg/kg and nZVI-contaminated soil was 1000 mg/kg in the transplantation method.

External Tank (ET) Foam Thermal/Structural Analysis Project

Science.gov (United States)

Moore, David F.; Ungar, Eugene K.; Chang, Li C.; Malroy, Eric T.; Stephan, Ryan A.

2008-01-01

An independent study was performed to assess the pre-launch thermally induced stresses in the Space Shuttle External Tank Bipod closeout and Ice/Frost ramps (IFRs). Finite element models with various levels of detail were built that included the three types of foam (BX-265, NCFI 24-124, and PDL 1034) and the underlying structure and bracketry. Temperature profiles generated by the thermal analyses were input to the structural models to calculate the stress levels. An area of high stress in the Bipod closeout was found along the aluminum tank wall near the phenolic insulator and along the phenolic insulator itself. This area of high stress might be prone to cracking and possible delamination. There is a small region of slightly increased stress in the NCFI 24-124 foam near its joint with the Bipod closeout BX-265 foam. The calculated stresses in the NCFI 24-124 acreage foam are highest at the NCFI 24-124/PDL 1034/tank wall interface under the LO2 and LH2 IFRs. The highest calculated stresses in the LH2 NCFI 24-124 foam are higher than in similar locations in the LO2 IFR. This finding is consistent with the dissection results of IFRs on ET-120.

Hydrogen peroxide treatment of TCE contaminated soil

International Nuclear Information System (INIS)

Hurst, D.H.; Robinson, K.G.; Siegrist, R.L.

1993-01-01

Solvent contaminated soils are ubiquitous in the industrial world and represent a significant environmental hazard due to their persistence and potentially negative impacts on human health and the environment. Environmental regulations favor treatment of soils with options which reduce the volume and toxicity of contaminants in place. One such treatment option is the in-situ application of hydrogen peroxide to soils contaminated with chlorinated solvents such as trichloroethylene (TCE). This study investigated hydrogen peroxide mass loading rates on removal of TCE from soils of varying organic matter content. Batch experiments conducted on contaminated loam samples using GC headspace analysis showed up to 80% TCE removal upon peroxide treatment. Column experiments conducted on sandy loam soils with high organic matter content showed only 25% TCE removal, even at hydrogen peroxide additions of 25 g peroxide per kg soil

International Space Station External Contamination Environment for Space Science Utilization

Science.gov (United States)

Soares, Carlos E.; Mikatarian, Ronald R.; Steagall, Courtney A.; Huang, Alvin Y.; Koontz, Steven; Worthy, Erica

2014-01-01

The International Space Station (ISS) is the largest and most complex on-orbit platform for space science utilization in low Earth orbit. Multiple sites for external payloads, with exposure to the associated natural and induced environments, are available to support a variety of space science utilization objectives. Contamination is one of the induced environments that can impact performance, mission success and science utilization on the vehicle. The ISS has been designed, built and integrated with strict contamination requirements to provide low levels of induced contamination on external payload assets. This paper addresses the ISS induced contamination environment at attached payload sites, both at the requirements level as well as measurements made on returned hardware, and contamination forecasting maps being generated to support external payload topology studies and science utilization.

Developing an integration tool for soil contamination assessment

Science.gov (United States)

Anaya-Romero, Maria; Zingg, Felix; Pérez-Álvarez, José Miguel; Madejón, Paula; Kotb Abd-Elmabod, Sameh

2015-04-01

In the last decades, huge soil areas have been negatively influenced or altered in multiples forms. Soils and, consequently, underground water, have been contaminated by accumulation of contaminants from agricultural activities (fertilizers and pesticides) industrial activities (harmful material dumping, sludge, flying ashes) and urban activities (hydrocarbon, metals from vehicle traffic, urban waste dumping). In the framework of the RECARE project, local partners across Europe are focusing on a wide range of soil threats, as soil contamination, and aiming to develop effective prevention, remediation and restoration measures by designing and applying targeted land management strategies (van Lynden et al., 2013). In this context, the Guadiamar Green Corridor (Southern Spain) was used as a case study, aiming to obtain soil data and new information in order to assess soil contamination. The main threat in the Guadiamar valley is soil contamination after a mine spill occurred on April 1998. About four hm3 of acid waters and two hm3 of mud, rich in heavy metals, were released into the Agrio and Guadiamar rivers affecting more than 4,600 ha of agricultural and pasture land. Main trace elements contaminating soil and water were As, Cd, Cu, Pb, Tl and Zn. The objective of the present research is to develop informatics tools that integrate soil database, models and interactive platforms for soil contamination assessment. Preliminary results were obtained related to the compilation of harmonized databases including geographical, hydro-meteorological, soil and socio-economic variables based on spatial analysis and stakeholder's consultation. Further research will be modellization and upscaling at the European level, in order to obtain a scientifically-technical predictive tool for the assessment of soil contamination.

Treatment of septic tank effluents by a full-scale capillary seepage soil biofiltration system.

Science.gov (United States)

Fan, Chihhao; Chang, Fang-Chih; Ko, Chun-Han; Teng, Chia-Ji; Chang, Tzi-Chin; Sheu, Yiong-Shing

2009-03-01

The purpose of this study is to evaluate the efficiency of septic tank effluent treatment by an underground capillary seepage soil biofiltration system in a suburban area of Taipei, Taiwan. In contrast to traditional subsurface wastewater infiltration systems, capillary seepage soil biofiltration systems initially draw incoming influent upwards from the distribution pipe by capillary and siphonage actions, then spread influent throughout the soil biofiltration bed. The underground capillary seepage soil biofiltration system consists of a train of underground treatment units, including one wastewater distribution tank, two capillary seepage soil biofiltration units in series, and a discharge tank. Each capillary seepage soil biofiltration unit contains one facultative digestion tank and one set of biofiltration beds. At the flow rate of 50 m3/day, average influent concentrations of biochemical oxygen demand (BOD), suspended solid (SS), ammonia nitrogen (NH3-N), and total phosphates (TP), were 36.15 mg/L, 29.14 mg/L, 16.05 mg/L, and 1.75 mg/L, respectively. After 1.5 years of system operation, the measured influent and effluent results show that the treatment efficiencies of the soil biofiltration system for BOD, SS, NH3-N, TP, and total coliforms are 82.96%, 60.95%, 67.17%, 74.86%, and 99.99%, respectively.

Speciation of zinc in contaminated soils

International Nuclear Information System (INIS)

Stephan, Chadi H.; Courchesne, Francois; Hendershot, William H.; McGrath, Steve P.; Chaudri, Amar M.; Sappin-Didier, Valerie; Sauve, Sebastien

2008-01-01

The chemical speciation of zinc in soil solutions is critical to the understanding of its bioavailability and potential toxic effects. We studied the speciation of Zn in soil solution extracts from 66 contaminated soils representative of a wide range of field conditions in both North America and Europe. Within this dataset, we evaluated the links among the dissolved concentrations of zinc and the speciation of Zn 2+ , soil solution pH, total soil Zn, dissolved organic matter (DOM), soil organic matter (SOM) and the concentrations of different inorganic anions. The solid-liquid partitioning coefficient (K d ) for Zn ranged from 17 to 13,100 L kg -1 soil. The fraction of dissolved Zn bound to DOM varied from 60% to 98% and the soil solution free Zn 2+ varied from 40% to 60% of the labile Zn. Multiple regression equations to predict free Zn 2+ , dissolved Zn and the solid-liquid partitioning of Zn are given for potential use in environmental fate modeling and risk assessment. The multiple regressions also highlight some of the most important soil properties controlling the solubility and chemical speciation of zinc in contaminated soils. - We studied the relationships among the chemical speciation of Zn in soil solution extracts from 66 contaminated soils and various physicochemical properties of the soils

Biological detoxification of a hydrocarbon contaminated soil

International Nuclear Information System (INIS)

Fabbri, F.; Lucchese, G.; Nardella, A.

2005-01-01

The soil quality of an industrial site chronically contaminated by 39000 mg/kg of oil was detrimentally affected. Soil treatments by bio-pile and land-farming resulted in a reduction of the level of contamination exceeding 90% of the original values, but without reaching regulatory limits. However, the bio-remediation treatments dramatically reduced the mobility of the contaminants and, accordingly, microbial tests clearly indicate that the soil quality improved to acceptable levels, similar to those typically observed in unaltered soils. Hydrocarbon mobility was estimated by the use of water and mild extractants (methanol and sodium dodecyl sulphate) to leach the contaminants from the soil; soil quality was evaluated by comparing the values of selected microbial and enzymatic parameters of the treated soil samples to reference values determined for natural soils. Microbial assessments included: measurement of the nitrification potential, dehydrogenase activity, measures of respiration and lipase activity, microbial counts (MPN on rich media) and Microtox TM assays of the water elutriate. Dermal absorption potential was evaluated using absorption on C 18 disks

The role of soil quality maps in the reuse of lightly contaminated soil

OpenAIRE

Lamé, F.P.J.; Leenaers, H.; Zegwaard, J.

2000-01-01

In 1999 the Dutch government agreed on a new policy regarding the reuse of lightly contaminated soil. From now on, lightly contaminated soil may be reused under conditions of soil-quality management. The municipal authorities supervise the reuse under this new regime. Two basic criteria need to be met before reuse of lightly contaminated soil is allowed. Firstly, the quality of the soil has to be characterised on a soil quality map. Secondly, the soil that will be reused has to be of the same...

Assessment of produced water contaminated soils to determine remediation requirements

International Nuclear Information System (INIS)

Clodfelter, C.

1995-01-01

Produced water and drilling fluids can impact the agricultural properties of soil and result in potential regulatory and legal liabilities. Produced water typically is classified as saline or a brine and affects surface soils by increasing the sodium and chloride content. Sources of produced water which can lead to problems include spills from flowlines and tank batteries, permitted surface water discharges and pit areas, particularly the larger pits including reserve pits, emergency pits and saltwater disposal pits. Methods to assess produced water spills include soil sampling with various chemical analyses and surface geophysical methods. A variety of laboratory analytical methods are available for soil assessment which include electrical conductivity, sodium adsorption ratio, cation exchange capacity, exchangeable sodium percent and others. Limiting the list of analytical parameters to reduce cost and still obtain the data necessary to assess the extent of contamination and determine remediation requirements can be difficult. The advantage to using analytical techniques is that often regulatory remediation standards are tied to soil properties determined from laboratory analysis. Surface geophysical techniques can be an inexpensive method to rapidly determine the extent and relative magnitude of saline soils. Data interpretations can also provide an indication of the horizontal as well as the vertical extent of impacted soils. The following discussion focuses on produced water spills on soil and assessment of the impacted soil. Produced water typically contains dissolved hydrocarbons which are not addressed in this discussion

Failure Analysis of a Helicopter External Fuel-Tank Pylon

Science.gov (United States)

Newman, John A.; Piascik, Robert S.; Lindenberg, Richard A.

2002-01-01

An eight-inch-long (0.2 m) crack was found in an external fuel-tank pylon of a U.S. Coast Guard HH-60 helicopter. The damaged pylon was removed from service and destructively examined at NASA Langley Research Center (LaRC) to determine the cause of the crack. Results of the analysis revealed that crack initiation occurred at corrosion pits in a fastener hole and crack propagation was a result of cyclic loading.

Testing of multistep soil washing for radiocesium-contaminated soil containing plant matter

International Nuclear Information System (INIS)

Funakawa, Masafumi; Tagawa, Akihiro; Okuda, Nobuyasu

2012-01-01

Decontamination work following radiocesium exposure requires a vast reduction in the amount of contaminated soil generated. The current study subjected 4 types of contaminated soil with different properties to multistep soil washing under the same conditions. This study also determined the effectiveness of radiocesium decontamination and the extent to which the amount of contaminated soil was reduced. In addition, the effectiveness of plant matter separation, adsorbent addition, and grinding as part of multistep soil washing was determined using the same contaminated soil. Results of testing indicated that the rate of radiocesium decontamination ranged from 73.6 to 89.2% and the recovery rate ranged from 51.5 to 84.2% for twice-treated soil, regardless of the soil properties or cesium level. Plant matter in soil had a high radiocesium level. However, there was little plant matter in our soil sample. Therefore, plant matter separation had little effect on the improvement in the percentage of radiocesium decontamination of twice-treated soil. Soil surface grinding improved the rate of radiocesium decontamination of twice-treated soil. However, radiocesium in soil tightly bound with minerals in the soil; thus, the addition of an adsorbent also failed to improve the rate of radiocesium decontamination. (author)

Contaminant Gradients in Trees: Directional Tree Coring Reveals Boundaries of Soil and Soil-Gas Contamination with Potential Applications in Vapor Intrusion Assessment.

Science.gov (United States)

Wilson, Jordan L; Samaranayake, V A; Limmer, Matthew A; Schumacher, John G; Burken, Joel G

2017-12-19

Contaminated sites pose ecological and human-health risks through exposure to contaminated soil and groundwater. Whereas we can readily locate, monitor, and track contaminants in groundwater, it is harder to perform these tasks in the vadose zone. In this study, tree-core samples were collected at a Superfund site to determine if the sample-collection location around a particular tree could reveal the subsurface location, or direction, of soil and soil-gas contaminant plumes. Contaminant-centroid vectors were calculated from tree-core data to reveal contaminant distributions in directional tree samples at a higher resolution, and vectors were correlated with soil-gas characterization collected using conventional methods. Results clearly demonstrated that directional tree coring around tree trunks can indicate gradients in soil and soil-gas contaminant plumes, and the strength of the correlations were directly proportionate to the magnitude of tree-core concentration gradients (spearman's coefficient of -0.61 and -0.55 in soil and tree-core gradients, respectively). Linear regression indicates agreement between the concentration-centroid vectors is significantly affected by in planta and soil concentration gradients and when concentration centroids in soil are closer to trees. Given the existing link between soil-gas and vapor intrusion, this study also indicates that directional tree coring might be applicable in vapor intrusion assessment.

Phytoremediation of soils contaminated with radionuclides

International Nuclear Information System (INIS)

Yamaguchi, Isamu

2004-01-01

Aiming at efficient phytoremediation of soils contaminated with radionuclides, we examined the effect of soil microbes on the uptake ability of plants using the multitracer technique to find that tomato rhizofungi in Fusarium spp. can stimulate the uptake of 85 Sr and 137 Cs by the plants. The synergic effect of a nonpathogenic strain of F. oxysporum on the uptake of radionuclides by plants proved to be enhanced by introducing a phytochelatin synthase gene into the fungus. Since soil contamination by radionuclides is still an unsolved problem in many parts of the world. Studies on phytoremediation of polluted soil environment will be important for developing effective strategies and devising adequate techniques to reduce human risks caused by food contamination of radionuclides. (author)

Combined in-situ and ex-situ bioremediation of petroleum hydrocarbon contaminated soils by closed-loop soil vapor extraction and air injection

International Nuclear Information System (INIS)

Hu, S.S.; Buckler, M.J.

1993-01-01

Treatment and restoration of petroleum hydrocarbon contaminated soils at a bulk petroleum above-ground storage tank (AST) site in Michigan is being conducted through in-situ and ex-situ closed-loop soil vapor extraction (SVE), soil vapor treatment, and treated air injection (AI) processes. The soil vapor extraction process applies a vacuum through the petroleum hydrocarbon affected soils in the ex-situ bio-remediation pile (bio-pile) and along the perimeter of excavated area (in-situ area) to remove the volatile or light petroleum hydrocarbons. This process also draws ambient air into the ex-situ bio-pile and in-situ vadose zone soil along the perimeter of excavated area to enhance biodegradation of light and heavy petroleum hydrocarbons in the soil. The extracted soil vapor is treated using a custom-designed air bio-remediation filter (bio-filter) to degrade the petroleum hydrocarbon compounds in the soil vapor extraction air streams. The treated air is then injected into a flush grade soil bed in the backfill area to perform final polishing of the air stream, and to form a closed-loop air flow with the soil vapor extraction perforated pipes along the perimeter of the excavated area

Thermal remediation of tar-contaminated soil and oil-contaminated gravel

International Nuclear Information System (INIS)

Anthony, E.J.; Wang, J.

2005-01-01

High temperature treatments are commonly considered for the decontamination of soil as they have the advantages of reliability, high capacity, and effective destruction of hazardous materials with reduced long-term liability. This paper examined the remediation of soil contaminated by coal tar as well as gravel contaminated by oil. Pilot plant studies were conducted using 2 representative incineration technologies: rotary kiln and fluidized bed. The coal tar contaminated soil had accumulated over a few decades at a calcination plant in western Canada. The soil was sticky and could not be handled by conventional feeding and combustion systems. Crushed lignite was mixed with the soil as an auxiliary fuel and to reduce stickiness. A pilot plant furnace was used to evaluate the potential of decontamination in a rotary calciner. An analysis of both a modelling study and the test results showed that complete decontamination could be achieved in the targeted calciner. The results suggested that energy recovery was also possible, which could in turn make the remediation process more cost-effective. Decontamination of oil-contaminated gravel was conducted with a pilot plant fluidized bed combustor to study the feasibility of using incineration technology in the remediation of gravel and debris contaminated by oil spills. Results indicated that the gravel was decontaminated with acceptable emission performance. It was concluded that the study will be valuable to the application of commercial incineration processes for the remediation of polluted soils. It was observed that the weathering of the oiled gravel lowered the rate of decontamination. A small amount of salt water resulted in lowered decontamination rates, which may be an important factor for situations involving the remediation of shoreline gravel contaminated by oil. 24 refs., 6 tabs., 7 figs

Uptake by Plants of Radiostrontium from Contaminated Soils

DEFF Research Database (Denmark)

Andersen, A. J.

1965-01-01

In a recent report from this department it was shown that the extractability of radiostrontium from contaminated soil samples was effectively reduced by heat treatment and by the addition of phosphate to the soil. It was pointed out that, under emergency conditions, heat-treatment of the contamin......In a recent report from this department it was shown that the extractability of radiostrontium from contaminated soil samples was effectively reduced by heat treatment and by the addition of phosphate to the soil. It was pointed out that, under emergency conditions, heat......-treatment of the contaminated soil surface and heavy phosphate application might thus reduce the uptake by plants of radiostrontium more efficiently than liming, which is only effective in soils of low calcium status. In the investigation reviewed here the influence of heat treatment and superphosphate application on the plant...... uptake of radiostrontium was examined in pot experiments. For comparison the effect of applying calcium carbonate to the contaminated soil surface was also determined....

The mathematical model accuracy estimation of the oil storage tank foundation soil moistening

Science.gov (United States)

Gildebrandt, M. I.; Ivanov, R. N.; Gruzin, AV; Antropova, L. B.; Kononov, S. A.

2018-04-01

The oil storage tanks foundations preparation technologies improvement is the relevant objective which achievement will make possible to reduce the material costs and spent time for the foundation preparing while providing the required operational reliability. The laboratory research revealed the nature of sandy soil layer watering with a given amount of water. The obtained data made possible developing the sandy soil layer moistening mathematical model. The performed estimation of the oil storage tank foundation soil moistening mathematical model accuracy showed the experimental and theoretical results acceptable convergence.

Remaining Sites Verification Package for the 100-D-9 Boiler Fuel Oil Tank Site. Attachment to Waste Site Reclassification Form 2006-030

International Nuclear Information System (INIS)

Dittmer, L.M.

2006-01-01

The 100-D-9 site is the former location of an underground storage tank used for holding fuel for the 184-DA Boiler House. Results of soil-gas samples taken from six soil-gas probes in a rectangle around the site the tank had been removed from concluded that there were no volatile organic compounds at detectable levels in the area. The 100-D-9 Boiler Fuel Oil Tank Site meets the remedial action objectives specified in the Remaining Sites ROD. The results demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River

Biological Treatment of Petroleum in Radiologically Contaminated Soil

Energy Technology Data Exchange (ETDEWEB)

BERRY, CHRISTOPHER

2005-11-14

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 the levels to less than 100 mg/kg in 22 months. After treatment, the soils were permanently disposed as low-level radiological waste. The petroleum and radiologically contaminated soil (PRCS) bioreactor operated using bioventing to control the supply of oxygen (air) to the soil being treated. The system treated 3.67 tons of PCRS amended with weathered compost, ammonium nitrate, fertilizer, and water. In addition, a consortium of microbes (patent pending) isolated at the Savannah River National Laboratory from a petroleum-contaminated site was added to the PRCS system. During operation, degradation of petroleum waste was accounted for through monitoring of carbon dioxide levels in the system effluent. The project demonstrated that co-contaminated soils could be successfully treated through bioventing and bioaugmentation to remove petroleum contamination to levels below 100 mg/kg while protecting workers and the environment from radiological contamination.

Effects of Two Kinds of Biochars on Soil Cu Availability in Contaminated Soil

Directory of Open Access Journals (Sweden)

WANG Xiao-qi

2016-07-01

Full Text Available This paper is aimed to research the impacts of different biochars(0,1%,2%,4%, including maize biochar and phytolacca root biochar, on rape growth and the soil Cu availability in the Cu-contaminated red soil via a series of pot experiments. The results showed that, compared with the control, the addition of two kinds of biochars could increase the biomass of the rape. In low Cu-contaminated red soil, added 4% maize biochar and phytolacca root biochar increased the biomass by 21.2 times and 67.9 times; however, the biomass were increased by 8.6 times and 109.6 times under high Cu-contaminated soil. The addition of phytolacca root biochar could increase the soil pH significantly, which has been increased by 0.4~1.6 units with the addition of phytolacca root biochar in low Cu-contaminated red soil, and it had 0.25~1.35 units more than that with maize biochar; In high Cu-contaminated red soil, with the addition of phytolacca root biochar, soil pH was increased by 0.33~1.52 units, which was 0.3~1.25 units higher than maize biochar. There was a significant effect on reducing the soil Cu availability with the addition of the two biochars. Among them, 4% addition of maize biochar and phytolacca root biochar could reduce soil available Cu content by 21.9% and 45.2% in low Cu-contaminated soil, however, it was decreased by 41.9% and 53.8% in high Cu-contaminated soil. Both of the two biochars were able to reduce the Cu accumulation in rape, where there was a decrease by 21.2% and 67.8% with he addition of 4% maize biochar and phytolacca root biochar under low Cu-contaminated soil, and it was decreased by 19.9% and 66.8% in high Cu-contaminated soil respectively. Both of the biochars could ameliorate the acidity and Cu availability in the red soil, enhance the biomass of the rape and reduce the Cu accumulation in rape, but phytolacca root biochar had more effective influence than maize biochar.

Soil sampling for environmental contaminants

International Nuclear Information System (INIS)

2004-10-01

The Consultants Meeting on Sampling Strategies, Sampling and Storage of Soil for Environmental Monitoring of Contaminants was organized by the International Atomic Energy Agency to evaluate methods for soil sampling in radionuclide monitoring and heavy metal surveys for identification of punctual contamination (hot particles) in large area surveys and screening experiments. A group of experts was invited by the IAEA to discuss and recommend methods for representative soil sampling for different kinds of environmental issues. The ultimate sinks for all kinds of contaminants dispersed within the natural environment through human activities are sediment and soil. Soil is a particularly difficult matrix for environmental pollution studies as it is generally composed of a multitude of geological and biological materials resulting from weathering and degradation, including particles of different sizes with varying surface and chemical properties. There are so many different soil types categorized according to their content of biological matter, from sandy soils to loam and peat soils, which make analytical characterization even more complicated. Soil sampling for environmental monitoring of pollutants, therefore, is still a matter of debate in the community of soil, environmental and analytical sciences. The scope of the consultants meeting included evaluating existing techniques with regard to their practicability, reliability and applicability to different purposes, developing strategies of representative soil sampling for cases not yet considered by current techniques and recommending validated techniques applicable to laboratories in developing Member States. This TECDOC includes a critical survey of existing approaches and their feasibility to be applied in developing countries. The report is valuable for radioanalytical laboratories in Member States. It would assist them in quality control and accreditation process

Organic contaminants in soil : desorption kinetics and microbial degradation

NARCIS (Netherlands)

Schlebaum, W.

1999-01-01

The availability of organic contaminants in soils or sediments for microbial degradation or removal by physical means (e.g.) soil washing or soil venting) depends on the desorption kinetics of these contaminants from the soil matrix. When the organic contaminants desorb very slow from the

Hanford Tanks 241-C-203 and 241-C-204: Residual Waste Contaminant Release Model and Supporting Data

Energy Technology Data Exchange (ETDEWEB)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Schaef, Herbert T.

2004-10-28

This report describes the development of release models for key contaminants that are present in residual sludge remaining after closure of Hanford Tanks 241-C-203 (C-203) and 241-C-204 (C-204). The release models were developed from data generated by laboratory characterization and testing of samples from these two tanks. Key results from this work are (1) future releases from the tanks of the primary contaminants of concern (99Tc and 238U) can be represented by relatively simple solubility relationships between infiltrating water and solid phases containing the contaminants; and (2) high percentages of technetium-99 in the sludges (20 wt% in C-203 and 75 wt% in C-204) are not readily water leachable, and, in fact, are very recalcitrant. This is similar to results found in related studies of sludges from Tank AY-102. These release models are being developed to support the tank closure risk assessments performed by CH2M HILL Hanford Group, Inc., for the U.S. Department of Energy.

Hanford Tanks 241-C-203 and 241-C-204: Residual Waste Contaminant Release Model and Supporting Data

International Nuclear Information System (INIS)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Schaef, Herbert T.

2004-01-01

This report describes the development of release models for key contaminants that are present in residual sludge remaining after closure of Hanford Tanks 241-C-203 (C-203) and 241-C-204 (C-204). The release models were developed from data generated by laboratory characterization and testing of samples from these two tanks. Key results from this work are (1) future releases from the tanks of the primary contaminants of concern (99Tc and 238U) can be represented by relatively simple solubility relationships between infiltrating water and solid phases containing the contaminants; and (2) high percentages of technetium-99 in the sludges (20 wt% in C-203 and 75 wt% in C-204) are not readily water leachable, and, in fact, are very recalcitrant. This is similar to results found in related studies of sludges from Tank AY-102. These release models are being developed to support the tank closure risk assessments performed by CH2M HILL Hanford Group, Inc., for the U.S. Department of Energy

Surfactant screening of diesel-contaminated soil

International Nuclear Information System (INIS)

Peters, R.W.; Shem, L.; Montemagno, C.D.; Lewis, B.

1991-01-01

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 21 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

Bioremediation of soils contaminated with fuel oils

International Nuclear Information System (INIS)

Baker, K.H.; Herson, D.S.; Vercellon-Smith, P.; Cronce, R.C.

1991-01-01

A utility company discovered soils in their plant contaminated with diesel fuel and related fuel oils (300-450 ppm). The soils were excavated and removed to a concrete pad for treatment. The authors conducted laboratory studies to determine if biostimulation or bioaugmentation would be appropriate for treating the soils. Microbial numbers and soil respiration were monitored in microcosms supplemented with: (1) organic nutrients, (2) inorganic nutrients, and (3) inorganic nutrients plus additional adapted microorganisms. Their studies indicated that biostimulation via the addition of inorganic nutrients would be appropriate at this site. Treatment cells for the contaminated soils were constructed. Initial data indicates that a 35% reduction in the concentration of contaminants has occurred within the first month of operation

Analysis of stress concentration in the Dutton groove regions of the Super Lightweight External Tank

Science.gov (United States)

Ahmed, R.

1995-05-01

Because the 2195 aluminum-lithium material of the super lightweight external tank (SLWT ET) has a lower toughness than the 2219 aluminum used in previous ET's, careful attention must be paid to stress concentrations. This report details the analysis performed on some of the stress concentrations in the orthogrid panels of the liquid hydrogen tank.

Bioremediation of petroleum-contaminated soil

International Nuclear Information System (INIS)

Pearce, K.; Snyman, H.G.; Oellermann, R.A.; Gerber, A.

1995-01-01

A pilot-scale study was conducted to evaluate the application of land-farming techniques in bioremediating a soil highly contaminated with petroleum products. A commercial biosupplement, and one prepared with indigenous microorganisms from the contaminated soil, were tested. Application of either of the biosupplements, in addition to the control of pH, moisture, and oxygen levels, resulted in a 94% reduction of the initial total petroleum hydrocarbon concentration (TPHC) (32% mass/mass) over a 70-day period. Implementation of these findings at full scale to bioremediate highly weathered petroleum products showed an average reduction of 89% over 5.5 months. Target levels of 1,400 mg/kg soil were reached from an initial average TPHC concentration of 12,200 mg/kg soil

Soil carbon mineralization following biochar addition associated with external nitrogen

Directory of Open Access Journals (Sweden)

Rudong Zhao

2015-12-01

Full Text Available Biochar has been attracting increasing attention for its potentials of C sequestration and soil amendment. This study aimed to understand the effects of combining biochar with additional external N on soil C mineralization. A typical red soil (Plinthudults was treated with two biochars made from two types of plantation-tree trunks (soil-biochar treatments, and was also treated with external N (soil-biochar-N treatments. All treatments were incubated for 42 d. The CO2-C released from the treatments was detected periodically. After the incubation, soil properties such as pH, microbial biomass C (MBC, and microbial biomass N (MBN were measured. The addition of biochar with external N increased the soil pH (4.31-4.33 compared to the soil treated with external N only (4.21. This was not observed in the comparison of soil-biochar treatments (4.75-4.80 to soil only (4.74. Biochar additions (whether or not they were associated with external N increased soil MBC and MBN, but decreased CO2-C value per unit total C (added biochar C + soil C according to the model fitting. The total CO2-C released in soil-biochar treatments were enhanced compared to soil only (i.e., 3.15 vs. 2.57 mg and 3.23 vs. 2.45 mg, which was attributed to the labile C fractions in the biochars and through soil microorganism enhancement. However, there were few changes in soil C mineralization in soil-biochar-N treatments. Additionally, the potentially available C per unit total C in soil-biochar-N treatments was lower than that observed in the soil-biochar treatments. Therefore, we believe in the short term, that C mineralization in the soil can be enhanced by biochar addition, but not by adding external N concomitantly.

Bioremediation of Pyrene-Contaminated Soils Using Biosurfactant

Directory of Open Access Journals (Sweden)

Jorfi

2014-10-01

Full Text Available Background Polycyclic aromatic hydrocarbons (PAHs are persistence organic chemicals with proved carcinogenic and mutagenic hazards. These compounds are usually adsorbed in soils in vicinity of oil and gas industries. Bioremediation of PAHs contaminated soils is difficult due to hydrophobic nature of PAHs. Objectives The main purpose of the current study was to determine the pyrene removal efficiency in synthetically contaminated soil, using biosurfactant. Materials and Methods Four pure bacterial strains capable of pyrene degradation were isolated from contaminated soils via enrichment techniques. The soil samples were spiked with an initial pyrene concentration of 500 mg/kg and subjected to bioremediation using a mixed culture comprised of previously isolated strains, in addition to application of biosurfactant during 63 days. Results The pyrene removal efficiency in samples containing biosurfactant, without biosurfactant and controls, were 86.4%, 59.8% and 14%, respectively, after 63 days. The difference of pyrene removal efficiency between the biosurfactant-containing samples and the ones without it was significant (P < 0.05. Conclusions Application of rhamnolipid biosurfactant produced by Pseudomonas aeruginosa significantly improved pyrene removal in contaminated soils.

Development of Decontamination Process for Soil Contaminated Uranium

International Nuclear Information System (INIS)

Kim, Gye-Nam; Kim, Seung-Soo; Park, Uk-Rang; Han, Gyu-Seong; Moon, Jei-Kwon

2014-01-01

Various experiments with full-scaled electrokinetic equipment, soil washing equipment, and gravel washing equipment were performed to remove 238 U from contaminated soils of below 0.4 Bq/g. The repetition number and the removal efficiencies of the soil and gravel washing equipment were evaluated. The decontamination periods by the soil and gravel electrokinetic equipment were evaluated. Finally, a work process of full-scaled decontamination equipment was developed. Contaminated soils were classified into soils and gravels using a 8.0 cm sieve. Soils were sent to the soil washing equipment, while gravels were sent to the gravel washing equipment. Soils sent to the soil washing equipment were sent to the soil electrokinetic equipment after soil washing. A repetition number of soil washing was two times. The washed gravels were sent to the gravel electrokinetic equipment. Gravel contaminated with a high concentration requires crushing after gravel washing

Development of Decontamination Process for Soil Contaminated Uranium

Energy Technology Data Exchange (ETDEWEB)

Kim, Gye-Nam; Kim, Seung-Soo; Park, Uk-Rang; Han, Gyu-Seong; Moon, Jei-Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-10-15

Various experiments with full-scaled electrokinetic equipment, soil washing equipment, and gravel washing equipment were performed to remove {sup 238}U from contaminated soils of below 0.4 Bq/g. The repetition number and the removal efficiencies of the soil and gravel washing equipment were evaluated. The decontamination periods by the soil and gravel electrokinetic equipment were evaluated. Finally, a work process of full-scaled decontamination equipment was developed. Contaminated soils were classified into soils and gravels using a 8.0 cm sieve. Soils were sent to the soil washing equipment, while gravels were sent to the gravel washing equipment. Soils sent to the soil washing equipment were sent to the soil electrokinetic equipment after soil washing. A repetition number of soil washing was two times. The washed gravels were sent to the gravel electrokinetic equipment. Gravel contaminated with a high concentration requires crushing after gravel washing.

Analysis of soils contaminated with petroleum constituents

International Nuclear Information System (INIS)

O'Shay, T.A.; Hoddinott, K.

1994-01-01

This symposium was held in Atlanta, Georgia on June 24, 1993. The purpose of the symposium was to provide a forum for exchange of information on petroleum contaminated soils. When spilled on the ground, petroleum products can cause massive problems in the environment. In this Special Technical Publication (STP), papers were selected in two categories; the analytical procedures for soil contaminated with petroleum hydrocarbons and the behavior of hydrocarbon contaminated soils. Individual papers have been processed separately for inclusion in the appropriate data bases

Effect of soil fortified by polyurethane foam on septic tank effluent treatment.

Science.gov (United States)

Nie, J Y; Zhu, N W; Lin, K M; Song, F Y

2011-01-01

Fortified soil was made up of a mixture at a mass ratio 4/1000-6/1000 of sponge and natural soil according to the results of column experiment. The fortified soil had bigger porosity and higher hydraulic conductivity than the natural soil. The columns packed with 900 mm of the fortified soil endured a flow rate equivalent to 100 L/m(2)/d of septic tank effluent and the average chemical oxygen demand, nitrogen, and phosphorus removal rates were around 92%, 75% and 96%, respectively. After 100 weeks of operation, the saturated hydraulic conductivity of the fortified soil kept higher than 0.2 m/d. The bigger porosity of sponge improved the effective porosity, and the bigger specific surface area of sponge acted as an ideal support for biomat growth and ensured the sewage treatment performance of the fortified soil. The comparable performance was due to a similar and sufficient degree of soil clogging genesis coupled with bioprocesses that effectively purified the septic tank effluent given the adequate retention times.

Bioremediation potential of diesel-contaminated Libyan soil.

Science.gov (United States)

Koshlaf, Eman; Shahsavari, Esmaeil; Aburto-Medina, Arturo; Taha, Mohamed; Haleyur, Nagalakshmi; Makadia, Tanvi H; Morrison, Paul D; Ball, Andrew S

2016-11-01

Bioremediation is a broadly applied environmentally friendly and economical treatment for the clean-up of sites contaminated by petroleum hydrocarbons. However, the application of this technology to contaminated soil in Libya has not been fully exploited. In this study, the efficacy of different bioremediation processes (necrophytoremediation using pea straw, bioaugmentation and a combination of both treatments) together with natural attenuation were assessed in diesel contaminated Libyan soils. The addition of pea straw was found to be the best bioremediation treatment for cleaning up diesel contaminated Libyan soil after 12 weeks. The greatest TPH degradation, 96.1% (18,239.6mgkg(-1)) and 95% (17,991.14mgkg(-1)) were obtained when the soil was amended with pea straw alone and in combination with a hydrocarbonoclastic consortium respectively. In contrast, natural attenuation resulted in a significantly lower TPH reduction of 76% (14,444.5mgkg(-1)). The presence of pea straw also led to a significant increased recovery of hydrocarbon degraders; 5.7log CFU g(-1) dry soil, compared to 4.4log CFUg(-1) dry soil for the untreated (natural attenuation) soil. DGGE and Illumina 16S metagenomic analyses confirm shifts in bacterial communities compared with original soil after 12 weeks incubation. In addition, metagenomic analysis showed that original soil contained hydrocarbon degraders (e.g. Pseudoxanthomonas spp. and Alcanivorax spp.). However, they require a biostimulant (in this case pea straw) to become active. This study is the first to report successful oil bioremediation with pea straw in Libya. It demonstrates the effectiveness of pea straw in enhancing bioremediation of the diesel-contaminated Libyan soil. Copyright © 2016 Elsevier Inc. All rights reserved.

SOIL WASHING TREATABILITY TESTS FOR PESTICIDE- CONTAMINATED SOIL

Science.gov (United States)

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...

Detection of leaks in underground storage tanks using electrical resistance methods: 1996 results

International Nuclear Information System (INIS)

Ramirez, A.; Daily, W.

1996-10-01

This document provides a summary of a field experiment performed under a 15m diameter steel tank mockup located at the Hanford Reservation, Washington. The purpose of this test was to image a contaminant plume as it develops in soil under a tank already contaminated by previous leakage and to determine whether contaminant plumes can be detected without the benefit of background data. Measurements of electrical resistance were made before and during a salt water release. These measurements were made in soil which contained the remnants of salt water plumes released during previous tests in 1994 and in 1995. About 11,150 liters of saline solution were released along a portion of the tank's edge in 1996. Changes in electrical resistivity due to release of salt water conducted in 1996 were determined in two ways: (1) changes relative to the 1996 pre-spill data, and (2) changes relative to data collected near the middle of the 1996 spill after the release flow rate was increased. In both cases, the observed resistivity changes show clearly defined anomalies caused by the salt water release. These results indicate that when a plume develops over an existing plume and in a geologic environment similar to the test site environment, the resulting resistivity changes are easily detectable. Three dimensional tomographs of the resistivity of the soil under the tank show that the salt water release caused a region of low soil resistivity which can be observed directly without the benefit of comparing the tomograph to tomographs or data collected before the spill started. This means that it may be possible to infer the presence of pre-existing plumes if there is other data showing that the regions of low resistivity are correlated with the presence of contaminated soil. However, this approach does not appear reliable in defining the total extent of the plume due to the confounding effect that natural heterogeneity has on our ability to define the margins of the anomaly

Superfund record of decision (EPA Region 4): Potter's septic tank service pits site, Brunswick County, Sandy Creek, NC. (First remedial action), August 1992. Final report

International Nuclear Information System (INIS)

1992-01-01

The 5-acre Potter's Septic Tank Service Pits (Potter's Pits) is located in a rural section of Brunswick County, North Carolina. The site is situated within a residential community known as the Town of Sandy Creek. Disposal practices consisted of placing petroleum waste products and septic tank sludges either in shallow unlined pits or directly on the land surface. The ROD addresses the ground water treatment and contaminated soils at the site. Primary contaminants of concern affecting surface and subsurface soil are VOCs and semi-VOCs, including napthalene, metals, and pesticides. Ground water is contaminated with VOCs, including benzene, ethyl benzene, toluene; other organics including naphthalene, and xylenes; and metals, including chromium and lead. The selected remedial action for the site includes excavating all soils that exceed the soil clean-up standards; treating contaminated soils by using an onsite ex-situ thermal desorption process; performing secondary treatment of the concentrated organic contaminants, and sampling and analyzing the treatment residue

Algal tests with soil suspensions and elutriates: A comparative evaluation for PAH contaminated soils

DEFF Research Database (Denmark)

Baun, Anders; Justesen, Kasper Bo; Nyholm, Niels

2002-01-01

An algal growth inhibition test procedure with soil suspensions is proposed and evaluated for PAH-contaminated soil. The growth rate reduction of the standard freshwater green alga Pseudokirchneriella subcapitata (formerly known as Selenastrum capricornutum) was used as the toxicity endpoint......, and was quantified by measuring the fluorescence of solvent-extracted algal pigments. No growth rate reduction was detected for soil contents up to 20 g/l testing five non-contaminated Danish soils. Comparative testing with PAH-contaminated soil elutriates and soil suspensions showed that the suspensions had...

Flotation separation of uranium from contaminated soils

International Nuclear Information System (INIS)

Misra, M.; Mehta, R.; Garcia, H.; Chai, C.D.; Smith, R.W.

1995-01-01

The volume of low-level contaminated soil at the Department of Energy's Nuclear Weapon Sites are in the order of several million tons. Most of the contaminants are uranium, plutonium, other heavy metals and organic compounds. Selected physical separation processes have shown demonstrated potential in concentrating the radionuclides in a small fraction of the soil. Depending upon the size, nature of bonding and distributions of radionuclides, more than 90% of the radionuclide activity can be concentrated in a small volume of fraction of the soil. The physico-chemical separation processes such as flotation in a mechanical and microbubble tall column cell have shown promising applications in cleaning up the high volume contaminated soil

Bioremediation of petroleum-contaminated soil: A Review

Science.gov (United States)

Yuniati, M. D.

2018-02-01

Petroleum is the major source of energy for various industries and daily life. Releasing petroleum into the environment whether accidentally or due to human activities is a main cause of soil pollution. Soil contaminated with petroleum has a serious hazard to human health and causes environmental problems as well. Petroleum pollutants, mainly hydrocarbon, are classified as priority pollutants. The application of microorganisms or microbial processes to remove or degrade contaminants from soil is called bioremediation. This microbiological decontamination is claimed to be an efficient, economic and versatile alternative to physicochemical treatment. This article presents an overview about bioremediation of petroleum-contaminated soil. It also includes an explanation about the types of bioremediation technologies as well as the processes.

Bioremediation of uranium contaminated Fernald soils

International Nuclear Information System (INIS)

Delwiche, M.E.; Wey, J.E.; Torma, A.E.

1994-01-01

This study investigated the use of microbial bioleaching for removal of uranium from contaminated soils. The ability of bacteria to assist in oxidation and solubilization of uranium was compared to the ability of fungi to produce complexing compounds which have the same effect. Biosorption of uranium by fungi was also measured. Soil samples were examined for changes in mineralogical properties due to these processes. On the basis of these laboratory scale studies a generalized flow sheet is proposed for bioremediation of contaminated Fernald soils

Contaminant resorption during soil washing

International Nuclear Information System (INIS)

Gombert, D.

1993-01-01

To evaluate the applicability of soil washing to a specific site requires some basic research in how contaminants are bound. Much can be learned from sequential extraction methodology based on micronutrient bioavailability studies wherein the soil matrix is chemically dissected to selectively remove particular fixation mechanisms independently. This procedure uses a series of progressively more aggressive solvents to dissolve the principle phases that make up a soil, however, the published studies do not appear to consider the potential for a contaminant released from one type of site to resorb on another site during an extraction. This physical model assumes no ion exchange or adsorption at sites either previously occupied by other ions, or exposed by the dissolution. Therefore, to make engineering use of the sequential extraction data, the release of contamination must be evaluated relative to the effects of resorption. Time release studies were conducted to determine the optimum duration for extraction to maximize complete destruction of the target matrix fraction while minimizing contaminant resorption. Tests with and without a potassium brine present to inhibit cesium resorption indicated extraction efficiency could be enhanced by as much as a factor of ten using the brine

Bioremediation of lead contaminated soil with Rhodobacter sphaeroides.

Science.gov (United States)

Li, Xiaomin; Peng, Weihua; Jia, Yingying; Lu, Lin; Fan, Wenhong

2016-08-01

Bioremediation with microorganisms is a promising technique for heavy metal contaminated soil. Rhodobacter sphaeroides was previously isolated from oil field injection water and used for bioremediation of lead (Pb) contaminated soil in the present study. Based on the investigation of the optimum culturing conditions and the tolerance to Pb, we employed the microorganism for the remediation of Pb contaminated soil simulated at different contamination levels. It was found that the optimum temperature, pH, and inoculum size for R. sphaeroides is 30-35 °C, 7, and 2 × 10(8) mL(-1), respectively. Rhodobacter sphaeroides did not remove the Pb from soil but did change its speciation. During the bioremediation process, more available fractions were transformed to less accessible and inert fractions; in particular, the exchangeable phase was dramatically decreased while the residual phase was substantially increased. A wheat seedling growing experiment showed that Pb phytoavailability was reduced in amended soils. Results inferred that the main mechanism by which R. sphaeroides treats Pb contaminated soil is the precipitation formation of inert compounds, including lead sulfate and lead sulfide. Although the Pb bioremediation efficiency on wheat was not very high (14.78% root and 24.01% in leaf), R. sphaeroides remains a promising alternative for Pb remediation in contaminated soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Investigation of thermoelastic stresses induced at high altitudes on aircraft external fuel tanks

Science.gov (United States)

Mousseau, Stephanie Lynn Steber

As composite technology has grown over the past several decades, the use of composite materials in military applications has become more feasible and widely accepted. Although composite materials provide many benefits, including strength optimization and reduced weight, damage and repair of these materials creates an additional challenge, especially when operating in a marine environment, such as on a carrier deck. This is evident within the Navy, as excessive damage often leads to the scrapping of F/A-18 External Fuel Tanks. This damage comes in many forms, the most elusive of which is delamination. Often the delamination found on the tanks is beyond repairable limits and the cause unknown, making it difficult to predict and prevent. The purpose of this investigation was to study the structure of the Navy's 330 gallon External Fuel Tanks and investigate one potential cause of delamination, stresses induced at high altitudes by cold temperatures. A stress analysis was completed using finite element software, and validation of the model was accomplished through testing of a scale model specimen. Due to the difficulties in modeling and predicting delamination, such as unknown presence of voids and understanding failure criteria, delamination was not modeled in Abaqus, rather stresses were observed and characteristics were studied to understand the potential for delamination within the layup. In addition, studies were performed to understand the effect of material properties and layup sequence on the stress distribution within the tank. Alternative design solutions are presented which could reduce the radial stresses within the tank, and recommendations are made for further study to understand the trade-offs between stress, cost, and manufacturability.

Remediation of diesel-oil-contaminated soil using peat

International Nuclear Information System (INIS)

Ghaly, R.A.; Pyke, J.B.; Ghaly, A.E.; Ugursal, V.I.

1999-01-01

We investigated a remediation process for diesel-contaminated soil, in which water was used to remove the diesel from the soil and peat was used to absorb the diesel layer formed on the surface of the water. The percolation of water through the soil was uniform. The time required for water to percolate the soil and for the layers (soil, water, and diesel) to separate depended on the soil depth. Both the depth of soil and mixing affected the thickness of the diesel layer and thus diesel recovery from the contaminated soil. Higher diesel recovery was achieved with smaller soil depth and mixing. The initial moisture content and the lower heating value of the peat were 7.1% and 17.65 MJ/kg, respectively. The final moisture content and lower heating value of the diesel-contaminated peat obtained from the experiment with mixing were 8.65 - 10.80% and 32.57 - 35.81 MJ/kg, respectively. The energy content of the diesel-contaminated peat is much higher than that of coal, and the moisture content is within the range recommended for biomass gasification. (author)

Vadose zone characterization project at the Hanford Tank Farms: BY Tank Farm report

International Nuclear Information System (INIS)

Kos, S.E.

1997-02-01

The US Department of Energy Grand Junction Office (GJO) was tasked by the DOE Richland Operations Office (DOE-RL) to perform a baseline characterization of the contamination distributed in the vadoze zone sediment beneath and around the single-shell tanks (SSTs) at the Hanford Site. The intent of this characterization is to determine the nature and extent of the contamination, to identify contamination sources, and to develop a baseline of the contamination distribution that will permit future data comparisons. This characterization work also allows an initial assessment of the impacts of the vadose zone contamination as required by the Resource Conservation and Recovery Act (RCRA). This characterization project involves acquiring information about the vadose zone contamination with borehole geophysical logging methods and documenting that information in a series of reports. Data from boreholes surrounding each tank are compiled into individual Tank Summary Data Reports. The data from each tank farm are then compiled and summarized in a Tank Farm Report. This document is the Tank Farm Report for the BY Tank Farm

Vadose zone characterization project at the Hanford Tank Farms: BY Tank Farm report

Energy Technology Data Exchange (ETDEWEB)

Kos, S.E.

1997-02-01

The US Department of Energy Grand Junction Office (GJO) was tasked by the DOE Richland Operations Office (DOE-RL) to perform a baseline characterization of the contamination distributed in the vadoze zone sediment beneath and around the single-shell tanks (SSTs) at the Hanford Site. The intent of this characterization is to determine the nature and extent of the contamination, to identify contamination sources, and to develop a baseline of the contamination distribution that will permit future data comparisons. This characterization work also allows an initial assessment of the impacts of the vadose zone contamination as required by the Resource Conservation and Recovery Act (RCRA). This characterization project involves acquiring information about the vadose zone contamination with borehole geophysical logging methods and documenting that information in a series of reports. Data from boreholes surrounding each tank are compiled into individual Tank Summary Data Reports. The data from each tank farm are then compiled and summarized in a Tank Farm Report. This document is the Tank Farm Report for the BY Tank Farm.

Results for the second quarter 2014 tank 50 WAC slurry sample chemical and radionuclide contaminants

International Nuclear Information System (INIS)

Bannochie, C.

2014-01-01

This report details the chemical and radionuclide contaminant results for the characterization of the 2014 Second Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by DWPF & Saltstone Facility Engineering (DSFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System

Results For The Fourth Quarter 2014 Tank 50 WAC Slurry Sample: Chemical And Radionuclide Contaminants

Energy Technology Data Exchange (ETDEWEB)

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

2015-09-30

This report details the chemical and radionuclide contaminant results for the characterization of the Calendar Year (CY) 2014 Fourth Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by DWPF & Saltstone Facility Engineering (DSFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

Results For The Second Quarter 2013 Tank 50 WAC Slurry Sample: Chemical And Radionuclide Contaminants

Energy Technology Data Exchange (ETDEWEB)

Bannochie, Christopher J.

2013-07-31

This report details the chemical and radionuclide contaminant results for the characterization of the 2013 Second Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by Saltstone Facility Engineering (SFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

Method of disposing of earth contaminated by leaking underground storage tanks

International Nuclear Information System (INIS)

Ruehl, P.A.

1993-01-01

A process is described for disposing of earth contaminated with petroleum products from a leaking underground storage tank wherein the earth contains a significant amount of material comprised primarily of a mixture of one part Al 2 O 3 and two to three parts SiO 2 , the process comprising: digging up a leaking underground storage tank and the surrounding contaminated earth; separating the excavated earth into a Al 2 O 3 +SiO 2 material and a non-Al 2 O 3 + SiO 2 material; mixing the Al 2 O 3 + SiO 2 material and other cement precursor raw materials together to form a mixture, and grinding the mixture to form a feed mix; introducing the feed mix into a rotary cement kiln causing any remaining petroleum product contained therein to be volatilized and burned within the kiln as cement clinker is being produced; and grinding the cement clinker together to form cement which is free of petroleum product

Remediation of contaminated soil by cement treatment

International Nuclear Information System (INIS)

Dimovic, S.

2004-01-01

This manuscript presents the most applicable remedial technologies for contaminated soil with focus on cement stabilisation/solidification treatment. These technologies are examined in the light of soil contamination with depleted uranium in the large area of south Serbia,after Nato bombing 1999. (author) [sr

Potential radiological exposure rates resulting from hypothetical dome failure at Tank W-10

International Nuclear Information System (INIS)

1994-07-01

The main plant area at Oak Ridge National Laboratory (ORNL) contains 12 buried Gunite tanks that were used for the storage and transfer of liquid radioactive waste. Although the tanks are no longer in use, they are known to contain some residual contaminated sludges and liquids. In the event of an accidental tank dome failure, however unlikely, the liquids, sludges, and radioactive contaminants within the tank walls themselves could create radiation fields and result in above-background exposures to workers nearby. This Technical Memorandum documents a series of calculations to estimate potential radiological exposure rates and total exposures to workers in the event of a hypothetical collapse of a Gunite tank dome. Calculations were performed specifically for tank W-10 because it contains the largest radioactivity inventory (approximately half of the total activity) of all the Gunite tanks. These calculations focus only on external, direct gamma exposures for prescribed, hypothetical exposure scenarios and do not address other possible tank failure modes or routes of exposure. The calculations were performed with established, point-kernel gamma ray modeling codes

Potential radiological exposure rates resulting from hypothetical dome failure at Tank W-10

Energy Technology Data Exchange (ETDEWEB)

1994-07-01

The main plant area at Oak Ridge National Laboratory (ORNL) contains 12 buried Gunite tanks that were used for the storage and transfer of liquid radioactive waste. Although the tanks are no longer in use, they are known to contain some residual contaminated sludges and liquids. In the event of an accidental tank dome failure, however unlikely, the liquids, sludges, and radioactive contaminants within the tank walls themselves could create radiation fields and result in above-background exposures to workers nearby. This Technical Memorandum documents a series of calculations to estimate potential radiological exposure rates and total exposures to workers in the event of a hypothetical collapse of a Gunite tank dome. Calculations were performed specifically for tank W-10 because it contains the largest radioactivity inventory (approximately half of the total activity) of all the Gunite tanks. These calculations focus only on external, direct gamma exposures for prescribed, hypothetical exposure scenarios and do not address other possible tank failure modes or routes of exposure. The calculations were performed with established, point-kernel gamma ray modeling codes.

Screening of plants for phytoremediation of oil-contaminated soil.

Science.gov (United States)

Ikeura, Hiromi; Kawasaki, Yu; Kaimi, Etsuko; Nishiwaki, Junko; Noborio, Kosuke; Tamaki, Masahiko

2016-01-01

Several species of ornamental flowering plants were evaluated regarding their phytoremediation ability for the cleanup of oil-contaminated soil in Japanese environmental conditions. Thirty-three species of plants were grown in oil-contaminated soil, and Mimosa, Zinnia, Gazania, and cypress vine were selected for further assessment on the basis of their favorable initial growth. No significant difference was observed in the above-ground and under-ground dry matter weight of Gazania 180 days after sowing between contaminated and non-contaminated plots. However, the other 3 species of plants died by the 180th day, indicating that Gazania has an especially strong tolerance for oil-contaminated soil. The total petroleum hydrocarbon concentration of the soils in which the 4 species of plants were grown decreased by 45-49% by the 180th day. Compared to an irrigated plot, the dehydrogenase activity of the contaminated soil also increased significantly, indicating a phytoremediation effect by the 4 tested plants. Mimosa, Zinnia, and cypress vine all died by the 180th day after seeding, but the roots themselves became a source of nutrients for the soil microorganisms, which led to a phytoremediation effect by increase in the oil degradation activity. It has been indicated that Gazania is most appropriate for phytoremediation of oil-contaminated soil.

Surface soil contamination standards

International Nuclear Information System (INIS)

Boothe, G.F.

1979-01-01

The purpose of this document is to define surface soil contamination limits for radioactive materials below which posting, restrictions and environmental controls are not necessary in order to protect personnel and the environment. The standards can also be used to determine if solid waste or other material is contaminated relative to disposal requirements. The derivation of the standards is given

State-of-the-art of the Space Shuttle External Tank

Science.gov (United States)

Ronquillo, L.

The designation, structure and environment of the External Tank (ET) of the Space Shuttle as well as plans for increasing the facilities and tooling to meet the required production rate capability of 40 or more ETs per year in 1992 are described. Special attention is given to the weight reduction of ET, since 1.0 lb of weight saved on the empty structure translates into about 0.9 lb of additional payload. To determine the potentiality of the weight reduction, structural tests were conducted. It was found that the tank could function properly with interior support structures reduced, and selected stringers eliminated. It is reported that an alternate sprayable polyisocyanurate foam capable of replacing a foam insulation over ablator bilayer thermoprotective composite on the aft-dome of the tank was developed: a commercially available material was modified to adhere to the -423 F aluminum substrate in the 2000 F engine-plume radiant-heat environment. It is mentioned that the weight savings program which started in Oct. 1975 saved 6000 lb by Jan. 1979. To reduce weld testing time and gain 100 times the accuracy, an electromechanical check system was developed. Problems of using robots are discussed.

Analytical investigation of the influence of soil on tanks for seismic analysis of nuclear power plant

International Nuclear Information System (INIS)

Nakahara, M.; Wright, J.T.; Stevenson, J.D.

1983-01-01

When seismically designing equipment, such as ground supported tanks of nuclear power plants, the free field response spectra are normally applied to a model having a fixed base. The consideration of soil structure interaction, which routinely has been applied to nuclear power plant building structures constructed on the soil surface, has not normally been applied to equipment. In this study, the effect of soil structure interaction on seismic response of tanks will be evaluated as a function of soil surface stiffness and depth using the calculated soil stiffness equations developed by H. Tajimi. The authors investigated the influence of the soil properties and composition represented as soil springs which depend on the soil conditions (shear modulus, density, Poisson's ratio) and the depth of soil surface. The results of this study are presented in the form of graphs which may be used to identify the range of soil parameters which have a significant effect on the seismic response of typical nuclear power plant tanks. A typical example to express the influence of the soil surface for seismic response and vibrational characteristics is presented. (orig./HP)

Free-Spinning-Tunnel Investigation of a 1/28-Scale Model of the North American FJ-4 Airplane with External Fuel Tanks, TED No. NACA AD 3112

Science.gov (United States)

Healy, Frederick M.

1958-01-01

A supplementary investigation to determine the effect of external fuel tanks on the spin and recovery characteristics of a l/28-scale model of the North American FJ-4 airplane has been conducted in the Langley 20-foot free-spinning tunnel. The model had been extensively tested previously (NACA Research Memorandum SL38A29) and therefore only brief tests were made to evaluate the effect of tank installation. Erect spin tests of the model indicate that flat-type spins-are more prevalent with 200-gallon external fuel tanks than with tanks not installed. The recovery technique determined for spins without tanks, rudder reversal to full against the spin accompanied by simultaneous movement of ailerons to full with the spin, is recommended for spins encountered with external tanks installed. If inverted spins are encountered with external tanks installed, the tanks should be jettisoned and recovery attempted by rudder reversal to full against the spin with ailerons maintained at neutral.

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

International Nuclear Information System (INIS)

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

1996-01-01

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

Soil contamination studies

International Nuclear Information System (INIS)

1997-06-01

The objective of this project was to develop a quick screening method that accurately identifies and quantifies the amount of alpha-emitting radionuclides in infinitely-thick soil samples using a Frisch grid ionization chamber. An additional objective of the work was to provide the US Department of Energy, Nevada Operations Office and its contractors with information on the theoretical and actual measured results of atmospheric testing contamination of soil and water at the Nevada Test Site through a comprehensive search of existing literature

The Influence of Soil Chemical Factors on In Situ Bioremediation of Soil Contamination

Energy Technology Data Exchange (ETDEWEB)

Breedveld, Gijs D.

1997-12-31

Mineral oil is the major energy source in Western society. Production, transport and distribution of oil and oil products cause serious contamination problems of water, air and soil. The present thesis studies the natural biodegradation processes in the soil environment which can remove contamination by oil products and creosote. The main physical/chemical processes determining the distribution of organic contaminants between the soil solid, aqueous and vapour phase are discussed. Then a short introduction to soil microbiology and environmental factors important for biodegradation is given. There is a discussion of engineered and natural bioremediation methods and the problems related to scaling up laboratory experiments to field scale remediation. Bioremediation will seldom remove the contaminants completely; a residue remains. Factors affecting the level of residual contamination and the consequences for contaminant availability are discussed. Finally, the main findings of the work are summarized and recommendations for further research are given. 111 refs., 41 figs., 19 tabs.

Statistical sampling strategies for survey of soil contamination

NARCIS (Netherlands)

Brus, D.J.

2011-01-01

This chapter reviews methods for selecting sampling locations in contaminated soils for three situations. In the first situation a global estimate of the soil contamination in an area is required. The result of the surey is a number or a series of numbers per contaminant, e.g. the estimated mean

Vitrification of underground storage tanks: Technology development, regulatory issues, and cost analysis

International Nuclear Information System (INIS)

Tixier, J.S.; Corathers, L.A.; Anderson, L.D.

1992-03-01

In situ vitrification (ISV), developed by the Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE), is a thermal treatment process for the remediation of hazardous, radioactive, or mixed waste sites. The process has been broadly patented both domestically and abroad. Since the inception of ISV in 1980, developmental activities have been focused on applications to contaminated soils, and more recently the potential for application to buried wastes and underground structures (tanks). Research performed to date on the more advanced ISV applications (i.e., application to buried wastes and underground tanks) shows that significant technical and economic potential exists for using ISV to treat buried wastes and underground structures containing radionuclides and/or hazardous constituents. Present ISV applications are directed to the treatment of contaminated soils; the likelihood of using ISV to treat underground tanks depends on the resolution of significant technical and institutional issues related to this advanced application. This paper describes the ISV process and summarizes the technical progress of underground tank vitrification (UTV), discusses pertinent regulatory issues facing the use of UTV, and presents the potential cost of UTV relative to other remedial action alternatives

Implementation and planning of preventive and multi-layered contaminated water treatment

International Nuclear Information System (INIS)

Takahashi, Takeshi; Arai, Tomoyuki

2014-01-01

In Fukushima Daiichi D and D activities, one of the most challenging issues is contaminated water management. In order to control ground water inflow into the buildings so that amount of contaminated water does not increase and prevent contaminated water spread out to the environment including into the ocean, TEPCO are taking various measures: In order to remove contamination sources, the removal of the highly contaminated water in the seaside trenches are being implemented. And also, the acceleration of water purification is planned by contaminated water clean-up facility. For the purpose of Isolating water from contaminated sources, construction of the frozen-soil land-side wall started in order to prevent the groundwater from flowing in the area and contaminated water from flowing out from the area. In order to prevent leakage of contaminated water into the ocean, soil improvement with sodium silicate (liquid glass) and Installation of the sea-side impermeable walls are implemented. Furthermore, replacement of the flange-type tanks with welded-joint tanks to mitigate leakage risks is underway. (author)

Effects of past copper contamination and soil structure on copper leaching from soil

DEFF Research Database (Denmark)

Paradelo, M; Møldrup, Per; Arthur, Emmanuel

2013-01-01

Copper contamination affects biological, chemical, and physical soil properties and associated ecological functions. Changes in soil pore organization as a result of Cu contamination can dramatically affect flow and contaminant transport in polluted soils. This study assessed the influence of soil...... structure on the movement of water and Cu in a long-term polluted soil. Undisturbed soil cores collected along a Cu gradient (from about 20 to about 3800 mg Cu kg−1 soil) were scanned using X-ray computed tomography (CT). Leaching experiments were performed to analyze tracer transport, colloid leaching......, and dissolved organic carbon (DOC) and Cu losses. The 5% arrival time (t0.05) and apparent dispersivity (λapp) for tracer breakthrough were calculated by fitting the experimental data to a nonparametric, double-lognormal probability density function. Soil bulk density, which did not follow the Cu gradient...

Phyto-remediation of contaminated soils

International Nuclear Information System (INIS)

Chagvardieff, P.

2014-01-01

Some plants can be selected for their capacity to extract radionuclides from the soil, on the contrary other plants can be chosen for being able to produce food grade products in a contaminated environment. Modern genetic methods can be used to enhance these abilities and turn some plants into an efficient means in the managing of contaminated areas. The DEMETERRES project that gathers different research organisations like CEA, IRSN and INRA and industrial partners like AREVA and VEOLIA aims at developing innovative bio-technologies like phyto-extraction and environment friendly physico-chemical technologies for the remediation of contaminated soils. This project was launched in 2013 on a 5-year scheme and is expected to lead to industrial applications. (A.C.)

Bioremediation of soil contaminated crude oil by Agaricomycetes.

Science.gov (United States)

Mohammadi-Sichani, M Maryam; Assadi, M Mazaheri; Farazmand, A; Kianirad, M; Ahadi, A M; Ghahderijani, H Hadian

2017-01-01

One of the most important environmental problems is the decontamination of petroleum hydrocarbons polluted soil, particularly in the oil-rich country. Bioremediation is the most effective way to remove these pollutants in the soil. Spent mushroom compost has great ability to decompose lignin-like pollution. The purpose of this study was the bioremediation of soil contaminated with crude oil by an Agaricomycetes . Soil sample amended with spent mushroom compost into 3%, 5% and 10% (w/w) with or without fertilizer. Ecotoxicity germination test was conducted with Lipidium sativa . The amplified fragment (18 s rDNA) sequence of this mushroom confirmed that the strain belonged to Pleurotus ostreatus species with complete homology (100% identity). All tests experiment sets were effective at supporting the degradation of petroleum hydrocarbons contaminated soil after three months. Petroleum contaminated soil amended with Spent mushroom compost 10% and fertilizer removed 64.7% of total petroleum hydrocarbons compared control. The germination index (%) in ecotoxicity tests ranged from 60.4 to 93.8%. This showed that the petroleum hydrocarbons contaminated soil amended with 10% Spent mushroom compost had higher bioremediation ability and reduced soil toxicity in less than three months.

Analysis of heat-transfer measurements from 2 AEDC wind tunnels on the Shuttle external tank

Science.gov (United States)

Nutt, K. W.

1984-01-01

Previous aerodynamic heating tests have been conducted in the AEDC/VKF Supersonic Wind Tunnel (A) to aid in defining the design thermal environment for the space shuttle external tank. The quality of these data has been under discussion because of the effects of low tunnel enthalpy and slow model injection rates. Recently the AEDC/VKF Hypersonic Wind Tunnel (C) has been modified to provide a Mach 4 capability that has significantly higher tunnel enthalpy with more rapid model injection rates. Tests were conducted in Tunnel C at Mach 4 to obtain data on the external tank for comparison with Tunnel A results. Data were obtained on a 0.0175 scale model of the Space Shuttle Integrated Vehicle at Re/ft = 4 x 10 to the 6th power with the tunnel stagnation temperature varying from 740 to 1440 R. Model attitude varied from an angle of attack of -5 to 5 deg and an angle of sideslip of -3 to 3 deg. One set of data was obtained in Tunnel C at Re/ft = 6.9 x 10 to the 6th for comparison with flight data. Data comparisons between the two tunnels for numerous regions on the external tank are given.

Microbial diversity of septic tank effluent and a soil biomat.

Science.gov (United States)

Tomaras, Jill; Sahl, Jason W; Siegrist, Robert L; Spear, John R

2009-05-01

Microbial diversity of septic tank effluent (STE) and the biomat that is formed as a result of STE infiltration on soil were characterized by 16S rRNA gene sequence analysis. Results indicate that microbial communities are different within control soil, STE, and the biomat and that microbes found in STE are not found in the biomat. The development of a stable soil biomat appears to provide the best on-site water treatment or protection for subsequent groundwater interactions of STE.

Risk management guidelines for petroleum storage tank sites

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-10-01

These guidelines provide a site management process designed particularly for soil and groundwater pollution originating from existing or former petroleum storage tank (PST) facilities and provide uniform standards for the remediation of polluted PST sites in Alberta. The numerical criteria, risk management objectives and technical information described in this document were compiled from four documents including Remediation Guidelines for Petroleum Storage Tank Sites 1994, the Canada-Wide Standards for Petroleum Hydrocarbons in Soil, Alberta Soil and Water Quality Guidelines for Hydrocarbons at Upstream Oil and Gas Facilities, and Guidelines for Managing Risks at Contaminated Sites in Alberta. The changes in these updated guidelines reflect new remediation criteria and provide a process for determining alternate site-specific management objectives for more petroleum storage tank sites. The guidelines were developed using a risk-based approach that ensures the protection of human health, safety and the environment. The guidelines apply to aboveground and underground storage tank facilities that contain gasoline, diesel, heating oil, and aviation fuel. The guidelines specify requirements by Alberta Environment and the Alberta Fire Code. The chapter on risk management process included information on site investigation, determination of soil type, pollution source removal, land use assessment, selection of exposure pathways, depth of remediation, human inhalation and groundwater protection pathways, and verification of remediation. figs, 4 tabs., 2 appendices.

A survey of existing and emerging technologies for external detection of liquid leaks at the Hanford Site

International Nuclear Information System (INIS)

Lewis, R.E.; Teel, S.S.

1994-10-01

During the history of the Hanford Site, many structures were built that stored and transported liquids used for the production mission; some of these structures are still active. Active structures include underground storage tanks retention basins, and pipes and pipelines. Many of the liquids stored and transported in these structures are potentially hazardous to human health and the environment. Any leakage of liquids from active structures, has the added potential to mobilize contaminants in the unsaturated zone. Therefore, it is beneficial to monitor these structures for leaks. The purpose of tills report is to catalog existing and emerging technologies that have potential for the external monitoring of liquid leaks. The report will focus primarily on the needs at the Hanford Site tank farms that are located in the 200 Areas, but will also be relevant to other Hanford Site facilities. Leak detection systems, both external and internal, are currently used at some Hanford facilities. This report focuses on the detection of leaks as they migrate into the soils surrounding the facilities

Remediation of soil contaminated with polycyclic aromatic ...

African Journals Online (AJOL)

user

2011-02-14

Feb 14, 2011 ... The aim of this study was to determine ways of remediating soils contaminated with polycyclic aromatic hydrocarbons (PAHs) associated with crude oil. The study involves the use of planted cowpeas, mushrooms, algae, dead vegetable and live earthworm, and fire-heating of the contaminated garden soil ...

Biochar- and phosphate-induced immobilization of heavy metals in contaminated soil and water: implication on simultaneous remediation of contaminated soil and groundwater.

Science.gov (United States)

Liang, Yuan; Cao, Xinde; Zhao, Ling; Arellano, Eduardo

2014-03-01

Long-term wastewater irrigation or solid waste disposal has resulted in the heavy metal contamination in both soil and groundwater. It is often separately implemented for remediation of contaminated soil or groundwater at a specific site. The main objective of this study was to demonstrate the hypothesis of simultaneous remediation of both heavy metal contaminated soil and groundwater by integrating the chemical immobilization and pump-and-treat methods. To accomplish the objective, three experiments were conducted, i.e., an incubation experiment was first conducted to determine how dairy-manure-derived biochar and phosphate rock tailing induced immobilization of Cd in the Cd-contaminated soils; second, a batch sorption experiment was carried out to determine whether the pre-amended contaminated soil still had the ability to retain Pb, Zn and Cd from aqueous solution. BCR sequential extraction as well as XRD and SEM analysis were conducted to explore the possible retention mechanism; and last, a laboratory-scale model test was undertaken by leaching the Pb, Zn, and Cd contaminated groundwater through the pre-amended contaminated soils to demonstrate how the heavy metals in both contaminated soil and groundwater were simultaneously retained and immobilized. The incubation experiment showed that the phosphate biochar were effective in immobilizing soil Cd with Cd concentration in TCLP (toxicity characteristics leaching procedure) extract reduced by 19.6 % and 13.7 %, respectively. The batch sorption experiment revealed that the pre-amended soil still had ability to retain Pb, Zn, and Cd from aqueous solution. The phosphate-induced metal retention was mainly due to the metal-phosphate precipitation, while both sorption and precipitation were responsible for the metal stabilization in the biochar amendment. The laboratory-scale test demonstrated that the soil amended with phosphate removed groundwater Pb, Zn, and Cd by 96.4 %, 44.6 %, and 49.2 %, respectively, and the

Evaluation of hydrophobicity in PAH-contaminated soils during phytoremediation

International Nuclear Information System (INIS)

Cofield, Naressa; Banks, M. Katherine; Schwab, A. Paul

2007-01-01

The impact of recalcitrant organic compounds on soil hydrophobicity was evaluated in contaminated soil from a manufactured gas plant site following 12 months of phytoremediation. Significant reduction in soil wetting and water retention was observed in contaminated soil compared to an uncontaminated control. Phytoremediation was effective at reducing total PAHs by 69% with corresponding changes in soil classification from extremely hydrophobic (initial sample) to moderately-strongly hydrophobic (planted) and hydrophilic-very hydrophilic (unplanted) after 12 months. The greatest reduction in soil hydrophobicity was observed in the unplanted, unfertilized treatments that had the lowest removal rate of PAHs. The presence of plants may contribute to hydrophobicity in contaminated soil. - The presence of recalcitrant hydrophobic organic pollutants may enhance soil hydrophobicity

Soil Contamination and Remediation Strategies. Current research and future challenge

Science.gov (United States)

Petruzzelli, G.

2012-04-01

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

Chemical fingerprinting of hydrocarbon-contamination in soil.

Science.gov (United States)

Boll, Esther S; Nejrup, Jens; Jensen, Julie K; Christensen, Jan H

2015-03-01

Chemical fingerprinting analyses of 29 hydrocarbon-contaminated soils were performed to assess the soil quality and determine the main contaminant sources. The results were compared to an assessment based on concentrations of the 16 priority polycyclic aromatic hydrocarbons pointed out by the U.S. Environmental Protection Agency (EPAPAH16) and total petroleum hydrocarbon (TPH). The chemical fingerprinting strategy proposed in this study included four tiers: (i) qualitative analysis of GC-FID chromatograms, (ii) comparison of the chemical composition of both un-substituted and alkyl-substituted polycyclic aromatic compounds (PACs), (iii) diagnostic ratios of selected PACs, and (iv) multivariate data analysis of sum-normalized PAC concentrations. The assessment criteria included quantitative analysis of 19 PACs and C1-C4 alkyl-substituted homologues of naphthalene, fluorene, dibenzothiophene, phenanthrene, pyrene, and chrysene; and 13 oxygenated polycyclic aromatic compounds (O-PACs). The chemical composition of un-substituted and alkyl-substituted PACs and visual interpretation of GC-FID chromatograms were in combination successful in differentiating pyrogenic and petrogenic hydrocarbon sources and in assessing weathering trends of hydrocarbon contamination in the soils. Multivariate data analysis of sum-normalized concentrations could as a stand-alone tool distinguish between hydrocarbon sources of petrogenic and pyrogenic origin, differentiate within petrogenic sources, and detect weathering trends. Diagnostic ratios of PACs were not successful for source identification of the heavily weathered hydrocarbon sources in the soils. The fingerprinting of contaminated soils revealed an underestimation of PACs in petrogenic contaminated soils when the assessment was based solely on EPAPAH16. As alkyl-substituted PACs are dominant in petrogenic sources, the evaluation of the total load of PACs based on EPAPAH16 was not representative. Likewise, the O-PACs are not

The role of soil quality maps in the reuse of lightly contaminated soil

NARCIS (Netherlands)

Lamé, F.P.J.; Leenaers, H.; Zegwaard, J.

2000-01-01

In 1999 the Dutch government agreed on a new policy regarding the reuse of lightly contaminated soil. From now on, lightly contaminated soil may be reused under conditions of soil-quality management. The municipal authorities supervise the reuse under this new regime. Two basic criteria need to be

Surfactant screening of diesel-contaminated soil

International Nuclear Information System (INIS)

Peters, R.W.; Montemagno, C.D.; Shem, L.; Lewis, B.-A.

1992-01-01

At one installation in California, approximately 60,000 gal of No. 2 diesel fuel leaked into the subsurface environment, resulting in contamination at depths from 6 to 34 m below the surface. Argonne National Laboratory was contracted to perform treatability studies for site remediation. This paper summarizes a surfactant screening/surfactant flooding research program in which 22 surfactants were screened for their effectiveness in mobilizing 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 contaminated soil samples obtained from the site

Evaluating Contaminant Flux from the Vadose Zone to the Groundwater in the Hanford Central Plateau. SX Tank Farms Case Study

Energy Technology Data Exchange (ETDEWEB)

Truex, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Oostrom, Martinus [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Last, George V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Strickland, Christopher E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tartakovsky, Guzel D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-09-01

At the DOE Hanford Site, contaminants were discharged to the subsurface through engineered waste sites in the Hanford Central Plateau. Additional waste was released through waste storage tank leaks. Much of the contaminant inventory is still present within the unsaturated vadose zone sediments. The nature and extent of future groundwater contaminant plumes and the growth or decline of current groundwater plumes beneath the Hanford Central Plateau are a function of the contaminant flux from the vadose zone to the groundwater. In general, contaminant transport is slow through the vadose zone and it is difficult to directly measure contaminant flux in the vadose zone. Predictive analysis, supported by site characterization and monitoring data, was applied using a structured, systems-based approach to estimate the future contaminant flux to groundwater in support of remediation decisions for the vadose zone and groundwater (Truex and Carroll 2013). The SX Tank Farm was used as a case study because of the existing contaminant inventory in the vadose zone, observations of elevated moisture content in portions of the vadose zone, presence of a limited-extent groundwater plume, and the relatively large amount and wide variety of data available for the site. Although the SX Tank Farm case study is most representative of conditions at tank farm sites, the study has elements that are also relevant to other types of disposal sites in the Hanford Central Plateau.

Sorption of BTX mixtures to contaminated and uncontaminated site soils

International Nuclear Information System (INIS)

Uchrin, C.G.; Koshy, K.; Wojtenko, I.

1995-01-01

Both adsorption and desorption studies are being performed examining benzene, toluene, and meta-xylene (BTX) as single components, binary mixtures, and trinary mixture onto both existing contaminated soils as well as some uncontaminated reference soils. The contaminated soils were obtained from an oil refinery site and another industrial site in New Jersey. The oil refinery site soil did not exhibit significant amounts of either benzene, toluene or xylene but was contaminated with other compounds while the other industrial site soil was contaminated with toluene among other compounds. The organic carbon content of the soils ranged from 0.14 to 2.91 percent. Preliminary adsorption studies showed BTX to strongly sorb to these soils. The adsorption studies onto the reference soils also demonstrated the effect of organic matter on adsorption. Sequential batch desorption studies show the BTX to desorb quickly, reaching equilibrium within 48 hours. Long-term uptake and release were not noted with these soil/contaminant systems

Enhanced bioremediation of PAH contaminated soils from coal processing sites

International Nuclear Information System (INIS)

Joshi, M.M.; Lee, S.

1995-01-01

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

Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site.

Science.gov (United States)

Akbari, Ali; Ghoshal, Subhasis

2014-09-15

Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16-C34) in a pilot-scale biopile experiment conducted at 15°C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16-C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day(-1) in biopile tank compared to 0.11 day(-1) in slurry bioreactors for C16-C34 hydrocarbons, the biodegradation extents for this fraction were comparable in these two systems. Copyright © 2014 Elsevier B.V. All rights reserved.

A soil washing pilot plant for removing petroleum hydrocarbons from contaminated soils

International Nuclear Information System (INIS)

Toor, I.A.; Roehrig, G.R.

1992-01-01

A soil washing pilot plant was built and tested for its ability to remove petroleum hydrocarbons from certain soils. The ITEX soil washing pilot plant is a trailer mountable mobile unit which has a washing capacity of two tons per hour of contaminated soils. A benchscale study was carried out prior to the fabrication of the pilot plant. The first sample was contaminated with diesel fuel while the second sample was contaminated with crude oil. Various nonionic, cationic and anionic cleaning agents were evaluated for their ability to remove petroleum hydrocarbons from these materials. The nonionic cleaning agents were more successful in cleaning the soils in general. The ultimate surfactant choice was based on several factors including cost, biodegradability, cleaning efficiency and other technical considerations. The soil samples were characterized in terms of their particle size distributions. Commercial diesel fuel was carefully mixed in this sand to prepare a representative sample for the pilot plant study. Two pilot runs were made using this material. A multistage washing study was also conducted in the laboratory which indicates that the contamination level can be reduced to 100 ppm using only four stages. Because the pilot plant washing efficiency is twice as high, it is believed that ultimate contamination levels can be reduced to lower levels using the same number of stages. However, this hypothesis has not been demonstrated to date

Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site

International Nuclear Information System (INIS)

Akbari, Ali; Ghoshal, Subhasis

2014-01-01

Highlights: • Aeration and moisture addition alone caused extensive hydrocarbon biodegradation. • 30-day slurry reactor remediation endpoints attained in 385 days in biopiles. • High nitrogen concentrations inhibited hydrocarbon degradation. • Inhibition of biodegradation linked to lack of shifts in soil microbial community. - Abstract: Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16–C34) in a pilot-scale biopile experiment conducted at 15 °C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16–C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day −1 in biopile tank compared to 0.11 day −1 in slurry bioreactors for C16–C34 hydrocarbons, the biodegradation extents for this fraction were

Electroremediation of PCB contaminated soil combined with iron nanoparticles: Effect of the soil type

DEFF Research Database (Denmark)

Gomes, Helena I.; Dias-Ferreira, Celia; Ottosen, Lisbeth M.

2015-01-01

Polychlorinated biphenyls (PCB) are carcinogenic and persistent organic pollutants that accumulate in soils and sediments. Currently, there is no cost-effective and sustainable remediation technology for these contaminants. In this work, a new combination of electrodialytic remediation and zero...... nanoparticles. Remediation experiments are made with two different historically PCB contaminated soils, which differ in both soil composition and contamination source. Soil 1 is a mix of soils with spills of transformer oils, while Soil 2 is a superficial soil from a decommissioned school where PCB were used...... as windows sealants. Saponin, a natural surfactant, was also tested to increase the PCB desorption from soils and enhance dechlorination. Remediation of Soil 1 (with highest pH, carbonate content, organic matter and PCB concentrations) obtained the maximum 83% and 60% PCB removal with the two...

Evaluation of soil flushing of complex contaminated soil: An experimental and modeling simulation study

Energy Technology Data Exchange (ETDEWEB)

Yun, Sung Mi; Kang, Christina S. [Department of Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701 (Korea, Republic of); Kim, Jonghwa [Department of Industrial Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701 (Korea, Republic of); Kim, Han S., E-mail: hankim@konkuk.ac.kr [Department of Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701 (Korea, Republic of)

2015-04-28

Highlights: • Remediation of complex contaminated soil achieved by sequential soil flushing. • Removal of Zn, Pb, and heavy petroleum oils using 0.05 M citric acid and 2% SDS. • Unified desorption distribution coefficients modeled and experimentally determined. • Nonequilibrium models for the transport behavior of complex contaminants in soils. - Abstract: The removal of heavy metals (Zn and Pb) and heavy petroleum oils (HPOs) from a soil with complex contamination was examined by soil flushing. Desorption and transport behaviors of the complex contaminants were assessed by batch and continuous flow reactor experiments and through modeling simulations. Flushing a one-dimensional flow column packed with complex contaminated soil sequentially with citric acid then a surfactant resulted in the removal of 85.6% of Zn, 62% of Pb, and 31.6% of HPO. The desorption distribution coefficients, K{sub Ubatch} and K{sub Lbatch}, converged to constant values as C{sub e} increased. An equilibrium model (ADR) and nonequilibrium models (TSNE and TRNE) were used to predict the desorption and transport of complex contaminants. The nonequilibrium models demonstrated better fits with the experimental values obtained from the column test than the equilibrium model. The ranges of K{sub Ubatch} and K{sub Lbatch} were very close to those of K{sub Ufit} and K{sub Lfit} determined from model simulations. The parameters (R, β, ω, α, and f) determined from model simulations were useful for characterizing the transport of contaminants within the soil matrix. The results of this study provide useful information for the operational parameters of the flushing process for soils with complex contamination.

Enhanced ex-situ bioremediation of soil contaminated with ...

African Journals Online (AJOL)

contaminated soil. Thus, the objective of this study was to investigate the feasibility and effectiveness of using electrical biostimulation processes to enhance ex-situ bioremediation of soils contaminated with organic pollutants. The effect of ...

Soil remediation: humic acids as natural surfactants in the washings of highly contaminated soils

International Nuclear Information System (INIS)

Conte, Pellegrino; Agretto, Anna; Spaccini, Riccardo; Piccolo, Alessandro

2005-01-01

The remediation of the highly contaminated site around the former chemical plant of ACNA (near Savona) in Northern Italy is a top priority in Italy. The aim of the present work was to contribute in finding innovative and environmental-friendly technology to remediate soils from the ACNA contaminated site. Two soils sampled from the ACNA site (A and B), differing in texture and amount and type of organic contaminants, were subjected to soil washings by comparing the removal efficiency of water, two synthetic surfactants, sodium dodecylsulphate (SDS) and Triton X-100 (TX100), and a solution of a natural surfactant, a humic acid (HA) at its critical micelle concentration (CMC). The extraction of pollutants by sonication and soxhlet was conducted before and after the soil washings. Soil A was richer in polycyclic aromatic hydrocarbons, whereas soil B had a larger content of thiophenes. Sonication resulted more analytically efficient in the fine-textured soil B. The coarse-textured soil A was extracted with a general equal efficiency also by soxhlet. Clean-up by water was unable to exhaustively remove contaminants from the two soils, whereas all the organic surfactants revealed very similar efficiencies (up to 90%) in the removal of the contaminants from the soils. Hence, the use of solutions of natural HAs appears as a better choice for soil washings of highly polluted soils due to their additional capacity to promote microbial activity, in contrast to synthetic surfactants, for a further natural attenuation in washed soils. - Solutions of natural humic acids appear to be a better choice for washing highly polluted soils

Reactivity of Primary Soil Minerals and Secondary Precipitates Beneath Leaking Hanford Waste Tanks

International Nuclear Information System (INIS)

Nagy, Kathryn L.; Sturchio, Neil C.

2003-01-01

This project, renewal of a previous EMSP project of the same title, is in its first year of funding at the University of Illinois at Chicago. The purpose is to continue investigating rates and mechanisms of reactions between primary sediment minerals found in the Hanford subsurface and leaked waste tank solutions. The goals are to understand processes that result in (1) changes in porosity and permeability of the sediment and resultant changes in flow paths of the contaminant plumes, (2) formation of secondary precipitates that can take up contaminants in their structures, and (3) release of mineral components that can drive redox reactions affecting dissolved contaminant mobility. A post-doctoral scientist, Dr. Sherry Samson, has been hired and two masters of science students are beginning to conduct experimental research. One research project that is underway is focused on measurement of the dissolution rates of plagioclase feldspar in high pH, high nitrate, high Al-bearing solutions characteristic of the BX tank farms. The first set of experiments is being conduced at room temperature. Subsequent experiments will examine the role of temperature because tank solutions in many cases were near boiling when leakage is thought to have occurred and temperature gradients have been observed beneath the SX and BX tank farms. The dissolution experiments are being conducted in stirred-flow kinetic reactors using powdered labradorite feldspar from Pueblo Park, New Mexico

Prospects for separating heavy metal from contaminated soil

International Nuclear Information System (INIS)

Langen, M.; Hoberg, H.; Hamacher, B.

1994-01-01

For decades, large quantities of organic and inorganic pollutants have been brought into the soil as a result of the industrial operations of smelting and coking plants. This paper reports on the prospects of separating heavy metals from soil contaminated by smelting and coking plants by means of a physical/chemical washing procedure. Besides the description of virgin soil characteristics, cleaning results and process parameters of calssification, density separation and flotation processes are presented. It is shown that heavy metal pollution of virgin soil can be reduced by the classical process stages of soil washing. The metal content of virgin soil are critically assessed whereby the limits of the physical-chimical washing process will also be entered into. Emphasis is placed on the significance of the determination of limiting values for inorganic contamination, especially for soil contaminated with both organic and inorganic pollution. (orig.) [de

Source apportionment of heavy metals and ionic contaminants in rainwater tanks in a subtropical urban area in Australia.

Science.gov (United States)

Huston, R; Chan, Y C; Chapman, H; Gardner, T; Shaw, G

2012-03-15

Due to prolonged droughts in recent years, the use of rainwater tanks in urban areas has increased in Australia. In order to apportion sources of contribution to heavy metal and ionic contaminants in rainwater tanks in Brisbane, a subtropical urban area in Australia, monthly tank water samples (24 sites, 31 tanks) and concurrent bulk deposition samples (18 sites) were collected during mainly April 2007-March 2008. The samples were analysed for acid-soluble metals, soluble anions, total inorganic carbon and total organic carbon, and characteristics such as total solid and pH. The Positive Matrix Factorisation model, EPA PMF 3.0, was used to apportion sources of contribution to the contaminants. Four source factors were identified for the bulk deposition samples, including 'crustal matter/sea salt', 'car exhausts/road side dust', 'industrial dust' and 'aged sea salt/secondary aerosols'. For the tank water samples, apart from these atmospheric deposition related factors which contributed in total to 65% of the total contaminant concentration on average, another six rainwater collection system related factors were identified, including 'plumbing', 'building material', 'galvanizing', 'roofing', 'steel' and 'lead flashing/paint' (contributing in total to 35% of the total concentration on average). The Australian Drinking Water Guideline for lead was exceeded in 15% of the tank water samples. The collection system related factors, in particular the 'lead flashing/paint' factor, contributed to 79% of the lead in the tank water samples on average. The concentration of lead in tank water was found to vary with various environmental and collection system factors, in particular the presence of lead flashing on the roof. The results also indicated the important role of sludge dynamics inside the tank on the quality of tank water. Copyright © 2011 Elsevier Ltd. All rights reserved.

Risk assessment of soil contamination criteria

International Nuclear Information System (INIS)

King, C.M.; Marter, W.L.; Montaque, D.F.; Holton, G.A.

1987-06-01

Criteria have been developed to select radioactive and nonradioactive contaminants at waste sites detailed analysis and risk assessment. These criteria were based on soil and water quality guidelines developed by various government agencies to determine if the criteria were appropriate. We performed a risk assessment of a hypothetical site which contained radioactive and nonradioactive contaminants at levels equal to the criteria values. Risks to the public from atmospheric, surface water, and groundwater exposure pathways were examined. Health risks to the public from atmospheric releases of radioactive and nonradioactive materials from a waste at soil criteria contamination levels are low. Health risks to the maximally exposed individual to chemical carcinogens are considerably below traditional EPA action levels. And health risks to the maximally exposed individual to atmospherically released radioactive contaminants is 1.88 x 10 -7 , more than a factor of 5 less than 10 -6 . Based on our atmospheric exposure pathways analysis and risk assessment, the applied soil criteria are appropriate for screening out unimportant risk contributors to human health from atmospheric exposure pathways. 13 refs., 3 figs., 7 tabs

Soil bacteria for remediation of polluted soils

Energy Technology Data Exchange (ETDEWEB)

Springael, D; Bastiaens, L; Carpels, M; Mergaey, M; Diels, L

1996-09-18

Soil bacteria, specifically adapted to contaminated soils, may be used for the remediation of polluted soils. The Flemish research institute VITO has established a collection of bacteria, which were isolated from contaminated areas. This collection includes microbacteria degrading mineral oils (Pseudomonas sp., Acinetobacter sp. and others), microbacteria degrading polycyclic aromatic hydrocarbons (genera Sphingomonas and Mycobacterium), microbacteria degrading polychlorobiphenyls (genus Ralstonia and strains related to beta-Proteobacteria), and metal resistant bacteria with plasmid borne resistances to Cd, Zn, Ni, Co, Cu, Hg, and Cr. Bench-scale reactors were developed to investigate the industrial feasibility of bioremediation. Batch Stirred Tank Reactors were used to evaluate the efficiency of oil degraders. Soils, contaminated with non-ferrous metals, were treated using a Bacterial Metal Slurry Reactor. It was found that the reduction of the Cd concentration may vary strongly from sample to sample: reduction factors vary from 95 to 50%. Is was shown that Cd contained in metallic sinter and biologically unavailable Cd could not be removed.

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

Science.gov (United States)

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

2012-08-15

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%. Copyright © 2012 Elsevier Ltd. All rights reserved.

Investigations involving oxidation-reduction (REDOX) pretreatment in conjunction with biological remediation of contaminated soils

International Nuclear Information System (INIS)

Montemagno, C.D.; Peters, R.W.; Tyree, A.

1991-01-01

hydrogen peroxide treatment and ultraviolet irradiation as a means of pretreating the contaminated soil prior to biological remediation. The next section provides a description of the site and the contamination problem, and summarizes the results from the soil characterization portion of our study. This section is followed by the section which describes applications of REDOX systems for treatment of hydrocarbons. Site Description The soil samples for this study came from a U.S. military installation located on the west coast. Two 20,000-gallon underground storage tanks had been used since the early 20th century to store a number of organic materials. This site is located in a major metropolitan district overlooking a bay area

Investigations involving oxidation-reduction (REDOX) pretreatment in conjunction with biological remediation of contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Montemagno, C. D. [Argonne National Laboratory, Argonne, IL (United States); Peters, R. W.; Tyree, A.

1991-07-01

hydrogen peroxide treatment and ultraviolet irradiation as a means of pretreating the contaminated soil prior to biological remediation. The next section provides a description of the site and the contamination problem, and summarizes the results from the soil characterization portion of our study. This section is followed by the section which describes applications of REDOX systems for treatment of hydrocarbons. Site Description The soil samples for this study came from a U.S. military installation located on the west coast. Two 20,000-gallon underground storage tanks had been used since the early 20th century to store a number of organic materials. This site is located in a major metropolitan district overlooking a bay area.

T Tank Farm Interim Surface Barrier Demonstration--Vadose Zone Monitoring Plan

International Nuclear Information System (INIS)

Zhang, Z. F.; Keller, Jason M.; Strickland, Christopher E.

2007-01-01

The Hanford Site has 149 underground single-shell tanks that store hazardous radioactive waste. Many of these tanks and their associated infrastructure (e.g., pipelines, diversion boxes) have leaked. Some of the leaked waste has entered the groundwater. The largest known leak occurred from the T-106 Tank in 1973. Many of the contaminants from that leak still reside within the vadose zone beneath the T Tank Farm. CH2M Hill Hanford Group, Inc. seeks to minimize movement of this residual contaminant plume by placing an interim barrier on the surface. Such a barrier is expected to prevent infiltrating water from reaching the plume and moving it further. A plan has been prepared to monitor and determine the effectiveness of the interim surface barrier. Soil water content and water pressure will be monitored using off-the-shelf equipment that can be installed by the hydraulic hammer technique. In fiscal year 2006, two instrument nests were installed. Each instrument nest contains a neutron probe access tube, a capacitance probe, four heat-dissipation units, and a drain gauge to measure soil water flux. A meteorological station has been installed outside of the fence. In fiscal year 2007, two additional instrument nests are planned to be installed beneath the proposed barrier.

Remediation of a radioactively contaminated soil using a mobile soil-washing system

International Nuclear Information System (INIS)

Grant, D.C.; Lahoda, E.J.; Dietrich, A.J.; Weigle, D.H.; Keegan, C.P.; Sachse, J.D.

1993-01-01

In order to obtain free-release of a former uranium mining site in Texas, it was required that the surface soil meet specific radiological guidelines. The soil has been contaminated with uranium and radium as a result of the spillage of well-drilling material, process solutions, and ion exchange resins during mining. To meet the required guidelines, the contaminated soil had to be either removed and disposed of off-site or remediated. For economic and long-term liability reasons, remediation of the soil by soil washing was performed. The remediation of this site utilizing the Scientific Ecology Group's soil washing system is discussed in this paper

Uptake of Organic Contaminants from Soil into Vegetables and Fruits

DEFF Research Database (Denmark)

Trapp, Stefan; Legind, Charlotte Nielsen

2011-01-01

Contaminants may enter vegetables and fruits by several pathways: by uptake with soil pore water, by diffusion from soil or air, by deposition of soil or airborne particles, or by direct application. The contaminant-specific and plantspecific properties that determine the importance...... of these pathways are described in this chapter. A variety of models have been developed, specific for crop types and with steady-state or dynamic solutions. Model simulations can identify sensitive properties and relevant processes. Persistent, polar (log KOW contaminants have...... the highest potential for accumulation from soil, and concentrations in leaves may be several hundred times higher than in soil. However, for most contaminants the accumulation in vegetables or fruits is much lower. Lipophilic (log KOW > 3) contaminants are mainly transported to leaves by attached soil...

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

Science.gov (United States)

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

2017-12-01

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

Remaining Sites Verification Package for the 1607-F7, 141-M Building Septic Tank. Attachment to Waste Site Reclassification Form 2006-040

International Nuclear Information System (INIS)

Dittmer, L.M.

2006-01-01

The 1607-F7, 141-M Building Septic Tank waste site was a septic tank and drain field that received sanitary sewage from the former 141-M Building. Remedial action was performed in August and November 2005. The results of verification sampling demonstrate that residual contaminant concentrations support future unrestricted land uses that can be represented by a rural-residential scenario. These results also show that residual concentrations support unrestricted future use of shallow zone soil and that contaminant levels remaining in the soil are protective of groundwater and the Columbia River

Remediation of soils contaminated with heavy metals

Energy Technology Data Exchange (ETDEWEB)

Boni, M.R.; D' Aprile, L. [Univ. of Rome ' ' La Sapienza' ' , Dept. of Hydraulic Transportation and Roads (Italy)

2001-07-01

In December 1999 Italy issued the national regulation (DM 471/99) for the clean-up of contaminated sites. This regulation applies both to derelict and to still operating industrial plants and waste management facilities. Target concentration values for clean-up interventions are issued and the requirements for design and planning of technical operation are defined. The selection of the appropriate clean-up technology are based on the following main criteria: - reduce the concentration in environmental media and the migration of pollutants without removing soil off-site; - in order to reduce contaminated material removal and transportation, remedial actions of soil, subsoil and groundwater should preferably be based on in-situ treatments. In-situ technologies commonly applied in Italy to the remediation of soils contaminated by heavy metals (As, Cd, Cr, Hg, Pb) are: - containment (caps, vertical barriers); - soil flushing; - cement based solidification/stabilization. (orig.)

Petroleum Contaminated Soil Treatment Using Surfactant and Hydrogen Peroxide

Directory of Open Access Journals (Sweden)

Ilza Lobo

2010-12-01

Full Text Available The process of washing soil with surfactants, sodium lauryl ether sulphate (LESS and sodium lauryl sulphate (SDS was combined with chemical oxidation using hydrogen peroxide, with a view to in situ remediation of clay soil contaminated with hydrocarbons oil. The evaluation of the efficiency of the procedure was the removal of polyaromatic hydrocarbons and the comparison of physical and chemical characteristics of contaminated soil and uncontaminated from the same region. The combination of these two techniques, soil washing and application of an oxidizing agent, presented as a process of effective remediation for soils contaminated with petroleum products in subtropical regions.

Contaminant Leach Testing of Hanford Tank 241-C-104 Residual Waste

Energy Technology Data Exchange (ETDEWEB)

Cantrell, Kirk J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Snyder, Michelle M.V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-07-01

Leach testing of Tank C-104 residual waste was completed using batch and column experiments. Tank C-104 residual waste contains exceptionally high concentrations of uranium (i.e., as high as 115 mg/g or 11.5 wt.%). This study was conducted to provide data to develop contaminant release models for Tank C-104 residual waste and Tank C-104 residual waste that has been treated with lime to transform uranium in the waste to a highly insoluble calcium uranate (CaUO4) or similar phase. Three column leaching cases were investigated. In the first case, C-104 residual waste was leached with deionized water. In the second case, crushed grout was added to the column so that deionized water contacted the grout prior to contacting the waste. In the third case, lime was mixed in with the grout. Results of the column experiments demonstrate that addition of lime dramatically reduces the leachability of uranium from Tank C-104 residual waste. Initial indications suggest that CaUO4 or a similar highly insoluble calcium rich uranium phase forms as a result of the lime addition. Additional work is needed to definitively identify the uranium phases that occur in the as received waste and the waste after the lime treatment.

Phytoremediation of soils contaminated by cadmium

Science.gov (United States)

Watai, H.; Miyazaki, T.; Fujikawa, T.; Mizoguchi, M.

2004-12-01

Phytoremediation is a technique to clean up soils contaminated with heavy metals. Advantages of this method are that (1) This technique is suitable to cleanup soils slightly contaminated with heavy metals in relatively wide area. (2) The expense for clean up is lower than civil engineering techniques. (3) This method can remove heavy metals fundamentally from contaminated. (4) The heavy metals are able to recycle by ashing of plants. Many researches have been done on the phytoremediation up to now, but almost all these researches were devoted to clarify the phytoremediation from the view point of plants themselves. However, few efforts have been devoted to analyze the migrations of heavy metals in soils during the phytoremediation process. The objective of this study is to clarify the features of Cd migration when plant roots are absorbing Cd from the ambient soils. Especially, we focused on finding the Cd migration pattern by changing the soil condition such as plant growing periods, planting densities, and the initial Cd concentration in soils. We planted sunflowers in columns filled with Cd contaminated soils because sunflower is a well-known hyperaccumulator of Cd from soils. By cutting the shoots of plants at the soil surface, and by keeping the plant roots in the soils without disturbance, the Cd concentrations, moisture contents, pH distributions, EC distributions, and dry weight of residual roots in the soils were carefully analyzed. The experimental results showed that (1)The growth of the planted sunflowers were suffered by applying of Cd. (2)The decrease of suction was affected by water uptake by roots at the depth from 0 to 5 cm. Water contents with plants in soils decrease more than without plants. (3)Cd adsorption by roots was predominant within 5cm from soil surface. In addition, it was also shown that there was an optimal Cd concentration where Cd is most effectively adsorbed by the plant. In this experiment we found that 40 to 60 mg kg-1 was the

Germination and initial growth of Campomanesia xanthocarpa O. Berg. (Myrtaceae, in petroleum-contaminated soil and bioremediated soil

Directory of Open Access Journals (Sweden)

AM. Gogosz

Full Text Available In 2000 there was an oil spill at the Getúlio Vargas Refinery (REPAR in Paraná. Nearly five years after contamination and the use of bioremediation, a study was carried out to identify the effects of the contaminated soil and the bioremediated soil on the germination and initial growth of C. xanthocarpa. The experiment was established with soil from REPAR, with three treatment groups: contaminated soil (C, bioremediated soil (B and uncontaminated soil (U; with five repetitions of 50 seeds each. There was no significant difference in the percentage of germination and the speed of germination index. The production of total biomass (30 - 60 days and shoot biomass (60 days was greater in the bioremediated soil compared to the other treatments. The averages for the root biomass were lower in the contaminated soil than in the bioremediated soil. The shoot length and the total length of the seedling in the contaminated soil and uncontaminated soil were lower than in the bioremediated soil.

Hybrid electrokinetic method applied to mix contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Mansour, H.; Maria, E. [Dept. of Building Civil and Environmental Engineering, Concordia Univ., Montreal (Canada)

2001-07-01

Several industrials and municipal areas in North America are contaminated with heavy metals and petroleum products. This mix contamination presents a particularly difficult task for remediation when is exposed in clayey soil. The objective of this research was to find a method to cleanup mix contaminated clayey soils. Finally, a multifunctional hybrid electrokinetic method was investigated. Clayey soil was contaminated with lead and nickel (heavy metals) at the level of 1000 ppm and phenanthrene (PAH) of 600 ppm. Electrokinetic surfactant supply system was applied to mobilize, transport and removal of phenanthrene. A chelation agent (EDTA) was also electrokinetically supplied to mobilize heavy metals. The studies were performed on 8 lab scale electrokinetic cells. The mix contaminated clayey soil was subjected to DC total voltage gradient of 0.3 V/cm. Supplied liquids (surfactant and EDTA) were introduced in different periods of time (22 days, 42 days) in order to optimize the most excessive removal of contaminants. The ph, electrical parameters, volume supplied, and volume discharged was monitored continuously during each experiment. At the end of these tests soil and cathalyte were subjected to physico-chemical analysis. The paper discusses results of experiments including the optimal energy use, removal efficiency of phenanthrene, as well, transport and removal of heavy metals. The results of this study can be applied for in-situ hybrid electrokinetic technology to remediate clayey sites contaminated with petroleum product mixed with heavy metals (e.g. manufacture Gas Plant Sites). (orig.)

Bioremediation of contaminated soil: Strategy and case histories

International Nuclear Information System (INIS)

Balba, M.T.; Ying, A.C.; McNeice, T.G.

1991-01-01

Microorganisms are capable of degrading many kinds of xenobiotic compounds and toxic chemicals. These microorganisms are ubiquitous in nature and there are numerous cases in which long-term contamination of soil and groundwater has been observed. The persistence of the contamination is usually caused by the inability of micro-organisms to metabolize these compounds under the prevailing environmental conditions. Two general reasons account for the failure of microbes to degrade pollutants in any environment: (1) inherent molecular recalcitrance of the contaminants and (2) environmental factors. The inherent molecular recalcitrance is usually associated with xenobiotic compounds where the chemical structure of the molecule is such that microbes and enzymes required for its catabolism have not evolved yet in nature. The environmental factors include a range of physicochemical conditions which influence microbial growth and activity. Biological remediation of contaminated sites can be accomplished using naturally-occurring microorganisms to treat the contaminants. Only particular groups of microorganisms are capable of decomposing specific compounds. The development of a bioremediation program for a specific contaminated soil system usually includes: thorough site/soil/waste characterization; treatability studies; and design and implementation of the bioremediation plan. The results of in situ and ex situ treatment programs involving the cleanup of petroleum hydrocarbon-contaminated soil will be discussed in detail. The paper will address key issues affecting the success of the bioremediation process such as nutrient transport, metal precipitation and potential soil clogging, microbial inoculation, etc

Hanford Tanks 241-C-203 and 241 C 204: Residual Waste Contaminant Release Model and Supporting Data

Energy Technology Data Exchange (ETDEWEB)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Schaef, Herbert T.

2007-05-23

This report was revised in May 2007 to correct 90Sr values in Chapter 3. The changes were made on page 3.9, paragraph two and Table 3.10; page 3.16, last paragraph on the page; and Tables 3.21 and 3.31. The rest of the text remains unchanged from the original report issued in October 2004. This report describes the development of release models for key contaminants that are present in residual sludge remaining after closure of Hanford Tanks 241-C-203 (C-203) and 241-C-204 (C-204). The release models were developed from data generated by laboratory characterization and testing of samples from these two tanks. Key results from this work are (1) future releases from the tanks of the primary contaminants of concern (99Tc and 238U) can be represented by relatively simple solubility relationships between infiltrating water and solid phases containing the contaminants; and (2) high percentages of technetium-99 in the sludges (20 wt% in C-203 and 75 wt% in C-204) are not readily water leachable, and, in fact, are very recalcitrant. This is similar to results found in related studies of sludges from Tank AY-102. These release models are being developed to support the tank closure risk assessments performed by CH2M HILL Hanford Group, Inc., for the U.S. Department of Energy.

Biological technologies for the remediation of co-contaminated soil.

Science.gov (United States)

Ye, Shujing; Zeng, Guangming; Wu, Haipeng; Zhang, Chang; Dai, Juan; Liang, Jie; Yu, Jiangfang; Ren, Xiaoya; Yi, Huan; Cheng, Min; Zhang, Chen

2017-12-01

Compound contamination in soil, caused by unreasonable waste disposal, has attracted increasing attention on a global scale, particularly since multiple heavy metals and/or organic pollutants are entering natural ecosystem through human activities, causing an enormous threat. The remediation of co-contaminated soil is more complicated and difficult than that of single contamination, due to the disparate remediation pathways utilized for different types of pollutants. Several modern remediation technologies have been developed for the treatment of co-contaminated soil. Biological remediation technologies, as the eco-friendly methods, have received widespread concern due to soil improvement besides remediation. This review summarizes the application of biological technologies, which contains microbial technologies (function microbial remediation and composting or compost addition), biochar, phytoremediation technologies, genetic engineering technologies and biochemical technologies, for the remediation of co-contaminated soil with heavy metals and organic pollutants. Mechanisms of these technologies and their remediation efficiencies are also reviewed. Based on this study, this review also identifies the future research required in this field.

Waste reduction by separation of contaminated soils during environmental restoration

International Nuclear Information System (INIS)

Roybal, J.A.; Conway, R.; Galloway, B.; Vinsant, E.; Slavin, P.; Guerin, D.

1998-06-01

During cleanup of contaminated sites, Sandia National Laboratories, New Mexico (SNL/NM) frequently encounters soils with low-level radioactive contamination. The contamination is not uniformly distributed, but occurs within areas of clean soil. Because it is difficult to characterize heterogeneously contaminated soils in detail and to excavate such soils precisely using heavy equipment, it is common for large quantities of uncontaminated soil to be removed during excavation of contaminated sites. This practice results in the commingling and disposal of clean and contaminated material as low-level waste (LLW), or possibly low-level mixed waste (LLMW). Until recently, volume reduction of radioactively contaminated soil depended on manual screening and analysis of samples, which is a costly and impractical approach and does not uphold As Low As Reasonably Achievable (ALARA) principles. To reduce the amount of LLW and LLMW generated during the excavation process, SNL/NM is evaluating two alternative technologies. The first of these, the Segmented Gate System (SGS), is an automated system that located and removes gamma-ray emitting radionuclides from a host matrix (soil, sand, dry sludge). The matrix materials is transported by a conveyor to an analyzer/separation system, which segregates the clean and contaminated material based on radionuclide activity level. The SGS was used to process radioactively contaminated soil from the excavation of the Radioactive Waste Landfill. The second technology, Large Area Gamma Spectroscopy (LAGS), utilizes a gamma spec analyzer suspended over a slab upon which soil is spread out to a uniform depth. A counting period of approximately 30 minutes is used to obtain a full-spectrum analysis for the isotopes of interest. The LAGS is being tested on the soil that is being excavated from the Classified Waste Landfill

Solubility measurement of uranium in uranium-contaminated soils

International Nuclear Information System (INIS)

Lee, S.Y.; Elless, M.; Hoffman, F.

1993-08-01

A short-term equilibration study involving two uranium-contaminated soils at the Fernald site was conducted as part of the In Situ Remediation Integrated Program. The goal of this study is to predict the behavior of uranium during on-site remediation of these soils. Geochemical modeling was performed on the aqueous species dissolved from these soils following the equilibration study to predict the on-site uranium leaching and transport processes. The soluble levels of total uranium, calcium, magnesium, and carbonate increased continually for the first four weeks. After the first four weeks, these components either reached a steady-state equilibrium or continued linearity throughout the study. Aluminum, potassium, and iron, reached a steady-state concentration within three days. Silica levels approximated the predicted solubility of quartz throughout the study. A much higher level of dissolved uranium was observed in the soil contaminated from spillage of uranium-laden solvents and process effluents than in the soil contaminated from settling of airborne uranium particles ejected from the nearby incinerator. The high levels observed for soluble calcium, magnesium, and bicarbonate are probably the result of magnesium and/or calcium carbonate minerals dissolving in these soils. Geochemical modeling confirms that the uranyl-carbonate complexes are the most stable and dominant in these solutions. The use of carbonate minerals on these soils for erosion control and road construction activities contributes to the leaching of uranium from contaminated soil particles. Dissolved carbonates promote uranium solubility, forming highly mobile anionic species. Mobile uranium species are contaminating the groundwater underlying these soils. The development of a site-specific remediation technology is urgently needed for the FEMP site

Management and re-use of contaminated soils

International Nuclear Information System (INIS)

Nowicki, V.K.; LeBlanc, M.

1993-01-01

The volume occupied by petroleum-contaminated soils in landfill facilities could be totally eliminated by treatment of these soils in separate facilities. Once treated, the soils could be recycled. In New Brunswick, one such treatment facility was opened in 1992 adjacent to the Fredericton regional landfill site; a second site was opened near Moncton in 1992. These facilities receive petroleum-contaminated soil from such users as gasoline stations, bulk plants, institutions, and transport companies, as well as from oil spill sites. The types of contaminants present range from gasoline to heavy fuel oils and greases, and the soils can vary from clays to gravels. Incoming soils are layered on treatment pads and treated by bioremediation. A bionutrient mixture containing fertilizers plus an amount of adapted, naturally-occurring petroleum hydrocarbon degrading microorganisms is sprayed onto the pile layer by layer. Aeration tubing is also installed during this layering process. When the piles are complete, they are covered with black plastic and aerated. Bioremediation times vary from 10 to 24 weeks. The facility has successfully decontaminated over 20,000 tonnes of soil to date. The resulting soil can be used for such purposes as soil cover and backfill. The bioremediation process itself is portable and can be initiated at landfill sites themselves to reduce transport and handling costs. 16 refs., 4 figs

Micrometeorological methods for measurements of mercury emissions over contaminated soils

International Nuclear Information System (INIS)

Kim, K.H.; Lindberg, S.E.; Hanson, P.J.; Owens, J.; Myers, T.P.

1993-01-01

As part of a larger study involving development and application of field and laboratory methods (micrometeorological, dynamic enclosure chamber, and controlled laboratory chamber methods) to measure the air/surface exchange of Hg vapor, we performed a series of preliminary measurements over contaminated soils. From March--April 1993, we used the modified Bowen ratio (MBR) method to measure emission rates of mercury over a floodplain contaminated with mercury near Oak Ridge, TN. The mercury emission rates measured from contaminated EFPC soils using the MBR method during early spring show that (1) in all cases, the contaminated soils acted as a source of mercury to the atmosphere with source strengths ranging from 17 to 160 ng m -2 h -1 ; and (2) the strengths of mercury emissions can be greatly influenced by the combined effects of surface soil temperature, residence time of air masses over the source area, and turbulence conditions. The mercury fluxes measured in a controlled flow chamber indicate that contaminated soils can exhibit up to an order of magnitude higher emission rates of Hg under conditions of elevated soil temperature, soil structure disturbance, and high turbulence. Mercury emissions from contaminated soils exceeded emissions from background soils by one to two orders of magnitude

Biosensors for detection of mercury in contaminated soils

International Nuclear Information System (INIS)

Bontidean, Ibolya; Mortari, Alessia; Leth, Suzanne; Brown, Nigel L.; Karlson, Ulrich; Larsen, Martin M.; Vangronsveld, Jaco; Corbisier, Philippe; Csoeregi, Elisabeth

2004-01-01

Biosensors based on whole bacterial cells and on bacterial heavy metal binding protein were used to determine the mercury concentration in soil. The soil samples were collected in a vegetable garden accidentally contaminated with elemental mercury 25 years earlier. Bioavailable mercury was measured using different sensors: a protein-based biosensor, a whole bacterial cell based biosensor, and a plant sensor, i.e. morphological and biochemical responses in primary leaves and roots of bean seedlings grown in the mercury-contaminated soil. For comparison the total mercury concentration of the soil samples was determined by AAS. Whole bacterial cell and protein-based biosensors gave accurate responses proportional to the total amount of mercury in the soil samples. On the contrary, plant sensors were found to be less useful indicators of soil mercury contamination, as determined by plant biomass, mercury content of primary leaves and enzyme activities

Vadose zone characterization project at the Hanford Tank Farms: U Tank Farm Report

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-05-01

The U.S. Department of Energy Grand Junction Office (DOE-GJO) was tasked by the DOE Richland Operations Office (DOE-RL) to perform a baseline characterization of the gamma-ray-emitting radionuclides that are distributed in the vadose zone sediments beneath and around the single-shell tanks (SSTs) at the Hanford Site. The intent of this characterization is to determine the nature and extent of the contamination, to identify contamination sources when possible, and to develop a baseline of the contamination distribution that will permit future data comparisons. This characterization work also allows an initial assessment of the impacts of the vadose zone contamination as required by the Resource Conservation and Recovery Act (RCRA). This characterization project involves acquiring information regarding vadose zone contamination with borehole geophysical logging methods and documenting that information in a series of reports. This information is presently limited to detection of gamma-emitting radionuclides from both natural and man-made sources. Data from boreholes surrounding each tank are compiled into individual Tank Summary Data Reports. The data from each tank in a tank farm are then compiled and summarized in a Tank Farm Report. This document is the Tank Farm Report for the U Tank Farm. Logging operations used high-purity germanium detection systems to acquire laboratory-quality assays of the gamma-emitting radionuclides in the sediments around and below the tanks. These assays were acquired in 59 boreholes that surround the U Tank Farm tanks. Logging of all boreholes was completed in December 1995, and the last Tank Summary Data Report for the U Tank Farm was issued in September 1996.

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

Science.gov (United States)

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

2015-11-01

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

Removal of residual contaminants in petroleum-contaminated soil by Fenton-like oxidation

Energy Technology Data Exchange (ETDEWEB)

Lu Mang [School of Material Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen, 333001, Jiangxi Province (China); State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China); Zhang Zhongzhi, E-mail: zzzhang1955@hotmail.com [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China); Qiao Wei; Guan Yueming; Xiao Meng; Peng Chong [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China)

2010-07-15

The degradation of bioremediation residues by hydrogen peroxide in petroleum-contaminated soil was investigated at circumneutral pH using a Fenton-like reagent (ferric ion chelated with EDTA). Batch tests were done on 20 g soil suspended in 60 mL aqueous solution containing hydrogen peroxide and Fe{sup 3+}-EDTA complex under constant stirring. A slurry reactor was used to treat the soil based on the optimal reactant conditions. Contaminants were characterized by Fourier transform infrared spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry. The results showed that the optimal treatment condition was: the molar ratio of hydrogen peroxide to iron = 200:1, and pH 7.0. Under the optimum condition, total dichloromethane-extractable organics were reduced from 14,800 to 2300 mg kg{sup -1} soil when the accumulative H{sub 2}O{sub 2} dosage was 2.45 mol kg{sup -1} soil during the reactor treatment. Abundance of viable cells was lower in incubated Fenton-like treated soil than in untreated soil. Oxidation of contaminants produced remarkable compositional and structural modifications. A fused ring compound, identified as C{sub 34}H{sub 38}N{sub 1}, was found to exhibit the greatest resistance to oxidation.

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

Science.gov (United States)

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

2014-11-01

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. © 2014 SETAC.

Improving farm management by modeling the contamination of farm tank milk with butyric acid bacteria

NARCIS (Netherlands)

Vissers, M.M.M.; Driehuis, F.; Giffel, te M.C.; Jong, de P.; Lankveld, J.M.G.

2006-01-01

Control of contamination of farm tank milk (FTM) with the spore-forming butyric acid bacteria (BAB) is important to prevent the late-blowing defect in semi-hard cheeses. The risk of late blowing can be decreased via control of the contamination level of FTM with BAB. A modeling approach was applied

Multimedia risk-based soil cleanup at a gasoline-contaminated site using vapor extraction

International Nuclear Information System (INIS)

Mills, W.B.; Johnson, K.M.; Liu, S.; Loh, J.Y.; Lew, C.S.

1996-01-01

At a utility service center, gasoline from an underground storage tank had leaked into subsurface vadose zone soils for several years. To remediate the site, a soil vapor extraction (SVE) system was installed and operated. At the completion of the SVE operation, gasoline-containing residues in several confirmation soil borings exceeded agency-mandated cleanup levels. Rather than continue with SVE, a risk-based approach was developed to evaluate what levels of gasoline-containing residues could be left in the soil and still protect human health. The risk-based approach consisted of simulating the fate of chemical residues through the vadose zone and then into both the ground water and atmosphere. Receptor point concentrations were predicted, and health risks were assessed. The risk assessment concluded that ingestion of contaminated ground water and inhalation of air while showering were the largest potential contributors to risk, and that risks associated with inhalation of vapor-containing ambient air are small. However, all predicted risks are below the acceptable risk levels of 10 -6 individual cancer risk probability and 1.0 hazard index. Therefore, the lead agency accepted the recommendation that the site requires no further remediation. The service center continues normal operations today

Bioremediation of Pyrene-Contaminated Soils Using Biosurfactant

OpenAIRE

Jorfi; Rezaee; Jaafarzadeh; Esrafili; Akbari; Moheb Ali

2014-01-01

Background Polycyclic aromatic hydrocarbons (PAHs) are persistence organic chemicals with proved carcinogenic and mutagenic hazards. These compounds are usually adsorbed in soils in vicinity of oil and gas industries. Bioremediation of PAHs contaminated soils is difficult due to hydrophobic nature of PAHs. Objectives The main purpose of the current study was to determine the pyrene removal efficiency in synthetically contaminated ...

Airborne soil particulates as vehicles for Salmonella contamination of tomatoes.

Science.gov (United States)

Kumar, Govindaraj Dev; Williams, Robert C; Al Qublan, Hamzeh M; Sriranganathan, Nammalwar; Boyer, Renee R; Eifert, Joseph D

2017-02-21

The presence of dust is ubiquitous in the produce growing environment and its deposition on edible crops could occur. The potential of wind-distributed soil particulate to serve as a vehicle for S. Newport transfer to tomato blossoms and consequently, to fruits, was explored. Blossoms were challenged with previously autoclaved soil containing S. Newport (9.39log CFU/g) by brushing and airborne transfer. One hundred percent of blossoms brushed with S. Newport-contaminated soil tested positive for presence of the pathogen one week after contact (PCompressed air was used to simulate wind currents and direct soil particulates towards blossoms. Airborne soil particulates resulted in contamination of 29% of the blossoms with S. Newport one week after contact. Biophotonic imaging of blossoms post-contact with bioluminescent S. Newport-contaminated airborne soil particulates revealed transfer of the pathogen on petal, stamen and pedicel structures. Both fruits and calyxes that developed from blossoms contaminated with airborne soil particulates were positive for presence of S. Newport in both fruit (66.6%) and calyx (77.7%). Presence of S. Newport in surface-sterilized fruit and calyx tissue tested indicated internalization of the pathogen. These results show that airborne soil particulates could serve as a vehicle for Salmonella. Hence, Salmonella contaminated dust and soil particulate dispersion could contribute to pathogen contamination of fruit, indicating an omnipresent yet relatively unexplored contamination route. Copyright © 2016 Elsevier B.V. All rights reserved.

Electrokinetic Amendment in Phytoremediation of Mixed Contaminated Soil

International Nuclear Information System (INIS)

Chirakkara, Reshma A.; Reddy, Krishna R.; Cameselle, Claudio

2015-01-01

This study examines the effects of electrokinetic amendments for phytoremediation of mixed contaminated soil where typical silty clay soil was spiked with organic contaminants (naphthalene and phenanthrene) and heavy metal (lead, cadmium and chromium). The contaminated soil was treated with compost and placed in electrokinetic cells, which were seeded with oat plant or sunflower. Thirty days after germination, 25 V alternating current was applied to selected cells using graphite electrodes for 3 h per day. The plants were harvested after a growth period of 61 days. One cell remained unplanted to evaluate the effect of the electric current on the soil, alone. The results confirm a significant reduction of heavy metals and organic contaminants in soil. However, there was no noticeable improvement of heavy metal phytoextraction or PAH degradation due to the application of electric field despite the increase in biomass production by the plants subjected to the electric current. The electric potential application time and frequency are suggested to be increased to have noticeable effects in heavy metal uptake and PAHs degradation.

Surfactant-enhanced bioremediation of PAH- and PCB-contaminated soils

International Nuclear Information System (INIS)

Ghosh, M.M.; Yeom, I.T.; Shi, Z.; Cox, C.D.; Robinson, K.G.

1995-01-01

The role of surfactants in the desorption of soil-bound polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) was investigated. The solubilization of individual PAHs in an extract of a weathered, coal tar-contaminated soil containing a mixture of PAHs and other petroleum derivatives was found to be significantly less than that for pure compounds. Batch soil washing with Triton X-100 (a commercial, nonionic alkyl phenol ethoxylate) was found to increase the effective diffusion rate of PAHs from the contaminated soil by four orders of magnitude compared to that obtained by gas purging when the results were analyzed using a radial diffusion model. At concentrations of up to 24 times its critical micelle concentration (CMC), Triton X-100 did not seem to enhance hydrocarbon degradation in the coal tar-contaminated soil; however, the biosurfactant rhamnolipid R1, at a concentration of 50x CMC, increased the rate of mineralization of 4,4'-chlorinated biphenyl mobilized from a laboratory-contaminated soil by more than 60 times

Remediation Of Radioactive Contaminated Soil in Oil Fields

International Nuclear Information System (INIS)

Taha, A.A.; Hassib, G.M.; Ibrahim, Z.A.

2011-01-01

Radioactive contamination by naturally occurring radioactive materials (NORM) in evaporation pond has been evaluated. At several onshore oil field locations, the produced water is discharged to form artificial lagoons or ponds. Subsequently, the released waters drain to the ground leaving radioactive deposits associated with the soil that eventually require remedial action in accordance with radiation protection principles. The present study aims to investigate the remediation of contaminated soil in some oil fields and in this concern, two scenarios were proposed. The first scenario is studying the feasibility of using soil washing technique (a physical-chemical separation process) for removing radium-226 from the contaminated soil samples collected from an evaporating pond. The size/activity distribution analyses were carried out. The data obtained showed that almost 68 % of the investigated soil was coarse sand (≥ 300 μm), 28 % was medium and fine sand (≤300 μm and (≥75 μm) and only small fraction of 4 % was silt and clay (≤75 μm). A series of mild acids such as HCl and mild NaCl/HCl (chloride washing) were used for washing the investigated soil fractions. The obtained data showed that the coarse fraction ≥ 300 μm can be re mediated below a regulatory level of 1Bq/g. and the radium from this coarse fraction could be easily removed by screening and chloride washing. For the remediation of (≤ 300 μm and (≥ 75 μm soil fractions, a series of mild chloride washing experiments also showed that the chloride base (NaCl/HCl) was found to be potentially useful. However, there was a difficulty in achieving a low radium value in the fine (≥ 75 μm size fractions using chloride washing. The second scenario is to get rid of all contaminated soil and store it in a concrete basin through the program of radiological protection of personnel and environment. Preliminary gamma survey of contaminated soil showed that the significant area of the investigated

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

Science.gov (United States)

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

2017-04-01

Soil washing is a promising way to remediate arsenic-contaminated soils. Most research has mostly focused on seeking efficient extractants for removing arsenic, but not concerned with any changes in soil properties when using this technique. In this study, the removal of arsenic from a heavily contaminated soil employing different washing solutions including H 3 PO 4 , NaOH and dithionite in EDTA was conducted. Subsequently, the changes in soil physicochemical properties and phytotoxicity of each washing technique were evaluated. After washing with 2 M H 3 PO 4 , 2 M NaOH or 0.1 M dithionite in 0.1 M EDTA, the soil samples' arsenic content met the clean-up levels stipulated in China's environmental regulations. H 3 PO 4 washing decreased soil pH, Ca, Mg, Al, Fe, and Mn concentrations but increased TN and TP contents. NaOH washing increased soil pH but decreased soil TOC, TN and TP contents. Dithionite in EDTA washing reduced soil TOC, Ca, Mg, Al, Fe, Mn and TP contents. A drastic color change was observed when the soil sample was washed with H 3 PO 4 or 0.1 M dithionite in 0.1 M EDTA. After adjusting the soil pH to neutral, wheat planted in the soil sample washed by NaOH evidenced the best growth of all three treated soil samples. These results will help with selecting the best washing solution when remediating arsenic-contaminated soils in future engineering applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dynamics of natural rehabilitation of Cs 137 soil contamination at the late stage due to the Chernobyl NPP accident

International Nuclear Information System (INIS)

Germenchuk, M.G.; Zhukova, O.M.; Tretyakevich, S.S.; Koreniak, A.P.

2006-01-01

As a result of Chernobyl NPP accident, the greatest quantity of radionuclides has fallen on the territory of Belarus, therefore 23% of the territory have been contaminated with Cs 137 with a level exceeding 37 kBq/m 2 on the total area of 46.45 thousand km 2 that has led to the exclusion from an agricultural rotation 2,64 thousand km 2 of farmland. Now, external gamma-radiation on the territory of Belarus is formed due to 'Chernobyl' and 'global' (caused by tests of the nuclear weapon) radioactive losses. A contribution is also done by natural radioactivity. To-date, due to natural radionuclides decay a radiation conditions in zones of Chernobyl contamination has been stabilized and main dose formation radionuclide is Cs 137. In conformity with clause 4 of the Law 'On legal regime of territories, exposed to radioactive contamination after the Chernobyl nuclear power plant accident' the territory of the Republic of Belarus is divided into zones depending on radioactive contamination of soil by radionuclides and sizes of a mean-annual effective dose. The estimation of a dose of external irradiation demands establishment of interrelation between the level of soil contamination with radionuclides and created by them exposure dose power (EDP). As a quantitative size of this link, a normalized on density of contamination of soil Cs 137 EDP at 1 m height is most used which is formed by all radionuclides and is called the transition coefficient 'density of contamination of soil Cs 137 - EDP'. In the given work, empirical values of factor of transition on items of supervision of a network of the radiation monitoring, registered in National System of Environment Monitoring (NSEM) Republic of Belarus have been determined. The carried out data analysis for 1993-2003 showed, that: Value of transition factor within 10 years have changed from 0,054 μR/h/kBq·m 2 to 0,041 μR/h/kBq·m 2 (with 2,0 μR/h/Ci·km 2 to 1,5 μR/h/Ci·km 2 ). Decrease of EDP from 'Chernobyl' radioactive

Electrokinetic remediation of anionic contaminants from unsaturated soils

International Nuclear Information System (INIS)

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

1992-01-01

Heavy-metal contamination of soil and groundwater is a widespread problem in the DOE weapons complex, and for the nation as a whole. Electrokinetic remediation is one possible technique for in situ removal of such contaminants from unsaturated soils. In previous studies at Sandia National Laboratories, the electromigration of chromate ions and anionic dye ions have been demonstrated. This paper reports on a series of experiments that were conducted to study the effect of moisture content on the electromigration rate of anionic contaminants in unsaturated soil and determine the limiting moisture content for which electromigration occurs

Results for the Third Quarter 2014 Tank 50 WAC slurry sample: Chemical and radionuclide contaminants

Energy Technology Data Exchange (ETDEWEB)

Crawford, Charles L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-01-08

This report details the chemical and radionuclide contaminant results for the characterization of the 2014 Third Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time.¹ Information from this characterization will be used by DWPF & Saltstone Facility Engineering (DSFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

Ex-situ bioremediation of petroleum contaminated soil

International Nuclear Information System (INIS)

Minier, M.R.

1994-01-01

The use of stress acclimated bacteria and nutrient supplements to enhance the biodegradation of petroleum contaminated soil can be a cost effective and reliable treatment technology to reduce organic contaminant levels to below established by local, state, and federal regulatory clean-up criteria. This paper will summarize the results of a field study in which 12,000 yds 3 of petroleum contaminated soil was successfully treated via ex-situ bioremediation and through management of macro and micronutrient concentrations, as well as, other site specific environmental factors that are essential for optimizing microbial growth

CLOPYRALID DISSIPATION IN THE SOIL CONTAMINATED WITH HEAVY METALS

Directory of Open Access Journals (Sweden)

Mariusz Kucharski

2014-12-01

Full Text Available The aim of the studies was to determine the influence of copper and zinc contamination on clopyralid dissipation in soil. The experiment was carried out in laboratory conditions (plant growth chamber. Clopyralid was applied to three different soils [similar textures, pH, organic carbon content and contrasting copper and zinc content: soil natural contaminated with Cu and Zn (S1, soil with natural low Cu and Zn concentration (S2 and soil S21 prepared in the laboratory (S2 soil additionally contaminated with Cu and Zn salts in the amounts equivalent to contamination level of S1 soil]. Soil samples were taken for analyses for 1 hour (initial concentration and 2, 4, 8, 16, 32, 64 and 96 days after treatment. Clopyralid residue was analysed using GC/ECD (gas chromatography with electron capture detector. Good linearity was found between logarithmic concentration of clopyralid residues and time. The differences in Cu and Zn content influenced the clopyralid decay in soil. The values of DT50 obtained in the experiment ranged from 21 to 27 days. A high concentration of Cu and Zn in soil slowed down clopyralid degradation (the DT50 value was higher – 25–27 days.

Production of non-constructive concrete blocks using contaminated soil

NARCIS (Netherlands)

de Korte, A.C.J.; Brouwers, Jos

2009-01-01

In this research, a heavily contaminated humus-rich peat soil and a lightly contaminated humus-poor sand soil, extracted from a field location in the Netherlands, are immobilized. These two types of soil are very common in the Netherlands. The purpose is to develop financial feasible, good quality

Phyto remediation of PAH contaminated soil

International Nuclear Information System (INIS)

Petruzzelli, G.; Pedron, F.; Barbafieri, M.; Cervelli, St.; Vigna Guidi, G.

2005-01-01

Phyto-remediation may enhance degradation of organic compounds promoting an adequate substrate for microbial growth. The aim of this work was to evaluate the efficiency of two plant species, Lupinus albus and Zea mais, in the bio-remediation of a PAH contaminated soil. This soil has been collected in a contaminated industrial area in Italy characterized by PAH concentrations up to 16000 mg/Kg. Microcosms experiments were carried out by planting Lupinus albus and Zea mais in the polluted soil; controls without plants were run separately. Growing period lasted by three months. Plants favoured PAH biodegradation by percentages of 32% with Lupinus albus and 22% with Zea mais, with respect to non vegetated microcosms. (authors)

Remediation of lead contaminated soil

International Nuclear Information System (INIS)

Urban, W.; Krishnamurthy, S.

1992-01-01

Lead contaminated soil in urban area is of major concern because of the potential health risk to children. Many studies have established a direct correlation between lead in soil and elevated blood lead levels in children. In Minneapolis, Minnesota, Mielke et al. (1983) reported that 50% of the Hmong children with lead poisioning were in areas where soil lead levels were between 500 and 1000 micrograms per gram (ug/g), and 40% of the children suffering from lead poisioning lived in areas where soil lead levels exceeded 1000 ug/g. In urban areas, lead pollution in soil has come from many different sources. The sources include lead paint, lead batteries and automobile exhaust. Olson and Skogerbee (1975) found the following lead compounds in soils where the primary source of pollution was from automobiles: lead sulfate, lead oxide, lead dioxide, lead sulfide, and metallic lead. The primary form of lead found was lead sulfate. Lead sulfate, lead tetraoxide, white lead, and other forms of lead have been used in the manufacture of paints for houses. At present, two remediation techniques, solidification and Bureau of Mines fluosilicic acid leaching, are available for lead-contaminated sites. The objective of the present investigation at the Risk Reduction Engineering Laboratory (RREL), Edison, was to try to solubilize the lead species by appropriate reagents and then recover the contaminants by precipitation as lead sulfate, using environmentally acceptable methods. The apparatus used for mixing was a LabMaster mixer, with variable speed and high-shear impeller. Previous work had used nitric acid for dissolving metallic lead. Owing to the environmental concerns, it was decided to use acetic acid in the presence of oxygen. The theoretical justification for this approach is the favorable redox potential for the reaction between metallic lead, acetic acid, and gaseous oxygen

Microbial Diversity of Septic Tank Effluent and a Soil Biomat▿ †

Science.gov (United States)

Tomaras, Jill; Sahl, Jason W.; Siegrist, Robert L.; Spear, John R.

2009-01-01

Microbial diversity of septic tank effluent (STE) and the biomat that is formed as a result of STE infiltration on soil were characterized by 16S rRNA gene sequence analysis. Results indicate that microbial communities are different within control soil, STE, and the biomat and that microbes found in STE are not found in the biomat. The development of a stable soil biomat appears to provide the best on-site water treatment or protection for subsequent groundwater interactions of STE. PMID:19304840

Bioremediation of crude oil contaminated tea plantation soil using ...

African Journals Online (AJOL)

Crude oil contamination of soil is a major concern for tea industry in Assam, India. Crude oil is a persistent organic contaminant which alters soil physical and biochemical characteristics and makes tea plants more susceptible against crude oil contamination. Therefore, two native bacterial strains designated as AS 03 and ...

Use of coal ash in production of concrete containing contaminated sand

International Nuclear Information System (INIS)

Ezeldin, A.S.

1991-01-01

There are between 2 to 3.5 million underground storage tanks located throughout the nation. Most of these tanks, which store oils and gasolines, are leaking making them one of the primary sources of soil contamination. Adding coal ash or cement to contaminated soil has been used to obtain stationary and inert wastecrete. By using this procedure, stabilization (limiting the solubility and mobility of the contaminants) and solidification (producing a solid waste block) of contaminated soils are successfully achieved. This paper investigates another re-use option of coal ash and contaminated soils. An experimental study evaluating the effectiveness of using coal ash with oil contaminated sand in concrete production is presented. A control mix made of clean sand was designed to yield 500 psi of compressive strength. Sand, artificially contaminated with 3% by weight of motor oil, was used as clean sand replacement. Six concrete mixtures were tested in compression and flexure. The six mixtures were obtained by increasing the ratio of contaminated sand to clean sand, namely; 10%, 20% and 40% and by introducing coal ash to the concrete mixture, namely; 20% of the cement weight. The test results indicate that the inclusion of oil contaminated sand in concrete reduces the compressive and flexural strengths. However, this decrease in strength is compensated by introducing coal ash in the mixture. Regaining that strength offers the possibility of using such concrete as a construction material in special structural applications. More research is required to establish better understanding of that composite and suggest feasible applications

Feasilbility of phytoextraction to remediate cadmium and zinc contaminated soils

NARCIS (Netherlands)

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

2008-01-01

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

Feasibility of phytoextraction to remediate cadmium and zinc contaminated soils

NARCIS (Netherlands)

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

2008-01-01

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

Soil sealing degree as factor influencing urban soil contamination with polycyclic aromatic hydrocarbons (PAHs

Directory of Open Access Journals (Sweden)

Mendyk Łukasz

2016-03-01

Full Text Available The objective of the study was to determine role of soil sealing degree as the factor influencing soil contamination with polycyclic aromatic hydrocarbons (PAHs. The study area included four sampling sites located within the administrative boundaries of the Toruń city, Poland. Sampling procedure involved preparing soil pits representing three examples of soil sealing at each site: non-sealed soil as a control one (I and two degrees of soil sealing: semi-pervious surface (II and totally impervious surface (III. Together with basic properties defined with standard procedures (particle size distribution, pH, LOI, content of carbonates content of selected PAHs was determined by dichloromethane extraction using gas chromatography with mass spectrometric detection (GC-MS. Obtained results show that urban soils in the city of Toruń are contaminated with polycyclic aromatic hydrocarbons. Soil sealing degree has a strong influence on the soil contamination with polycyclic aromatic hydrocarbons. Totally sealed soils are better preserved from atmospheric pollution including PAHs. Combustion of grass/wood/coal was the main source of determined PAHs content in examined soils.

Soil mixing of stratified contaminated sands.

Science.gov (United States)

Al-Tabba, A; Ayotamuno, M J; Martin, R J

2000-02-01

Validation of soil mixing for the treatment of contaminated ground is needed in a wide range of site conditions to widen the application of the technology and to understand the mechanisms involved. Since very limited work has been carried out in heterogeneous ground conditions, this paper investigates the effectiveness of soil mixing in stratified sands using laboratory-scale augers. This enabled a low cost investigation of factors such as grout type and form, auger design, installation procedure, mixing mode, curing period, thickness of soil layers and natural moisture content on the unconfined compressive strength, leachability and leachate pH of the soil-grout mixes. The results showed that the auger design plays a very important part in the mixing process in heterogeneous sands. The variability of the properties measured in the stratified soils and the measurable variations caused by the various factors considered, highlighted the importance of duplicating appropriate in situ conditions, the usefulness of laboratory-scale modelling of in situ conditions and the importance of modelling soil and contaminant heterogeneities at the treatability study stage.

Bioremediation of diesel fuel contaminated soils

International Nuclear Information System (INIS)

Troy, M.A.; Jerger, D.E.

1992-01-01

Bioremediation techniques were successfully employed in the cost-effective cleanup of approximately 8400 gallons of diesel fuel which had been accidentally discharged at a warehouse in New Jersey. Surrounding soils were contaminated with the diesel fuel at concentrations exceeding 1,470 mg/kg total petroleum hydrocarbons as measured by infrared spectroscopy (TPH-IR, EPA method 418.1, modified for soils). This paper reports on treatment of the contaminated soils through enhanced biological land treatment which was chosen for the soil remediation pursuant to a New Jersey Pollutant Discharge Elimination System - Discharge to Ground Water (NJPDES-DGW) permit. Biological land treatment of diesel fuel focuses on the breakdown of the hydrocarbon fractions by indigenous aerobic microorganisms in the layers of soil where oxygen is made available. Metabolism by these microorganisms can ultimately reduce the hydrocarbons to innocuous end products. The purpose of biological land treatment was to reduce the concentration of the petroleum hydrocarbon constituents of the diesel fuel in the soil to 100 ppm total petroleum hydrocarbons (TPH)

Release behavior of triazine residues in stabilised contaminated soils

International Nuclear Information System (INIS)

Ying, G.G.; Kookana, R.S.; Mallavarpu, M.

2005-01-01

This paper reports the release behavior of two triazines (atrazine and simazine) in stabilised soils from a pesticide-contaminated site in South Australia. The soils were contaminated with a range of pesticides, especially with triazine herbicides. With multiple extractions of each soil sample with deionised water (eight in total), 15% of atrazine and 4% of simazine residues were recovered, resulting in very high concentrations of the two herbicides in leachate. The presence of small fractions of surfactants was found to further enhance the release of the residues. Methanol content up to 10% did not substantially influence the concentration of simazine and atrazine released. The study demonstrated that while the stabilisation of contaminated soil with particulate activated carbon (5%) and cement mix (15%) was effective in locking the residues of some pesticides, it failed to immobilise triazine herbicides residues completely. Given the higher water solubility of these herbicides than other compounds more effective strategies to immobilise their residues is needed. - Stabilisation of contaminated soil with a mix of activated carbon and cement may fail to immobilise some contaminants like triazines

Bioavailability assessment of contaminants in soils via respiration and nitrification tests

International Nuclear Information System (INIS)

Hund-Rinke, Kerstin; Simon, Markus

2008-01-01

For the assessment of contaminated soils ecotoxicological tests are used to estimate the bioavailability of contaminants in soil samples. Terrestrial tests reveal the habitat function of soils, and parameters applied in tests involving microorganisms include respiration activity and potential ammonium oxidation. For such tests, the threshold values needed to assess the results have already been established in guidelines ISO 17155 and ISO 15685. In this paper, we discuss about the respiration activity and potential ammonium oxidation results obtained from a wide variety of soils with different physico-chemical properties and levels of contamination. These results show that microbial respiration and potential ammonium oxidation have different sensitivities to various classes of contaminants. We demonstrated that both organic and inorganic contaminants influence potential ammonium oxidation, whereas microbial respiration is predominantly affected by biodegradable organic contaminants. These differences might be useful for more detailed assessments of soil contamination, leading to different recommended actions depending on which parameter is affected. - The paper provides a further criterion for a more detailed assessment of soil contamination, leading to different recommended actions depending on which parameter is affected

Bioavailability assessment of contaminants in soils via respiration and nitrification tests

Energy Technology Data Exchange (ETDEWEB)

Hund-Rinke, Kerstin [Fraunhofer Institute for Molecular Biology and Applied Ecology, Auf dem Aberg 1, 57392 Schmallenberg (Germany)], E-mail: kerstin.hund-rinke@ime.fraunhofer.de; Simon, Markus [Fraunhofer Institute for Molecular Biology and Applied Ecology, Auf dem Aberg 1, 57392 Schmallenberg (Germany)], E-mail: markus.simon@ime.fraunhofer.de

2008-05-15

For the assessment of contaminated soils ecotoxicological tests are used to estimate the bioavailability of contaminants in soil samples. Terrestrial tests reveal the habitat function of soils, and parameters applied in tests involving microorganisms include respiration activity and potential ammonium oxidation. For such tests, the threshold values needed to assess the results have already been established in guidelines ISO 17155 and ISO 15685. In this paper, we discuss about the respiration activity and potential ammonium oxidation results obtained from a wide variety of soils with different physico-chemical properties and levels of contamination. These results show that microbial respiration and potential ammonium oxidation have different sensitivities to various classes of contaminants. We demonstrated that both organic and inorganic contaminants influence potential ammonium oxidation, whereas microbial respiration is predominantly affected by biodegradable organic contaminants. These differences might be useful for more detailed assessments of soil contamination, leading to different recommended actions depending on which parameter is affected. - The paper provides a further criterion for a more detailed assessment of soil contamination, leading to different recommended actions depending on which parameter is affected.

SoilCAM: soil contamination: advanced integrated characterisation and time-lapse monitoring

NARCIS (Netherlands)

French, H.K.; Zee, van der S.E.A.T.M.; Meju, M.

2009-01-01

The SoilCAM project is aimed at improving current methods for monitoring contaminant distribution and biodegradation in the subsurface. Currently proven methods, based on invasive sampling of soil, soil water and gaseous phase, are unable to provide sufficiently accurate data with high enough

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

Science.gov (United States)

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

2014-01-01

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.

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

Directory of Open Access Journals (Sweden)

Brent F Kim

Full Text Available 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.

Effect of soil texture on phytoremediation of arsenic-contaminated soils

Science.gov (United States)

Pallud, C. E.; Matzen, S. L.; Olson, A.

2015-12-01

Soil arsenic (As) contamination is a global problem, resulting in part from anthropogenic activities, including the use of arsenical pesticides and treated wood, mining, and irrigated agriculture. Phytoextraction using the hyperaccumulating fern Pteris vittata is a promising new technology to remediate soils with shallow arsenic contamination with minimal site disturbance. However, many challenges still lie ahead for a global application of phytoremediation. For example, remediation times using P. vittata are on the order of decades. In addition, most research on As phytoextraction with P. vittata has examined As removal from sandy soils, where As is more available, with little research focusing on As removal from clayey soils, where As is less available. The objective of this study is to determine the effects of soil texture and soil fertilization on As extraction by P. vittata, to optimize remediation efficiency and decrease remediation time under complex field conditions. A field study was established 2.5 years ago in an abandoned railroad grade contaminated with As (average 85.5 mg kg-1) with texture varying from sandy loam to silty clay loam. Organic N, inorganic N, organic P, inorganic P, and compost were applied to separate sub-plots; control ferns were grown in untreated soil. In a parallel greenhouse experiment, ferns were grown in sandy loam soil extracted from the field (180 mg As kg-1), with similar treatments as those used at the field site, plus a high phosphate treatment and treatments with arbuscular mycorrhizal fungi. In the field study, fern mortality was 24% higher in clayey soil than in sandy soil due to waterlogging, while As was primarily associated with sandy soil. Results from the sandy loam soil indicate that soil treatments did not significantly increase As phytoextraction, which was lower in phosphate-treated ferns than in control ferns, both in the field and greenhouse study. Under greenhouse conditions, ferns treated with organic N were

Bio-mechanical removing of contaminated soils: a field experiment

International Nuclear Information System (INIS)

Jouve, A.; Maubert, H.; Schulte, E.

1992-01-01

If, in spite of safety precautions, a major nuclear accident would occur, countermeasures should be taken to attenuate the impact of radioactive deposits. The European RESSAC program (REhabilitation of Soils and Surfaces after an ACcident) aims at studying actions for normal life return in contaminated zones. One of them, called the Decontaminating Vegetal Network (D.V.N.) associates the biological action of turfing plants, producing a dense root-network capable to trap the top contaminated soil particles, and the mechanical efficiency of a turf harvester which can remove only 1 cm of soil. This performance, not associated with other techniques of soil removal such as scrapers or bulldozers, leads to minimize the waste production. The D.V.N is a vegetal cover spread over the contaminated soil, using the hydro-seeding technique. The growing plants are forming a pleasant lawn which may have a positive impact on the public opinion compared to techniques using bitumen mixtures to cover the soil. Field experiments involving labelling solutions of stable molybdenum salts simulating the contamination of the soil have shown that this technique can be applied as well on homogeneous cultivated soil surfaces as on roughly ploughed soils. 4 refs., 3 figs., 2 tabs

Plant uptake of radiocesium from contaminated soils

International Nuclear Information System (INIS)

Pipiska, M.; Lesny, J.; Hornik, M.; Augustin, J.

2004-01-01

Phytoextraction field experiments were conducted on soil contaminated with radiocesium to determine the capacity of autochthonous grasses and weeds to accumulate 137 Cs. The aim of the study was to evaluate the potential of spontaneously growing vegetation as a tool for decontamination of non-agricultural contaminated land. As a test field, the closed monitored area of the radioactive wastewater treatment plant of the Nuclear Power Plant in Jaslovskie Bohunice, Slovakia was used. contamination was irregularly distributed from the level of background to spots with maximal activity up to 900 Bq/g soil. Sequential extraction analysis of soil samples showed the following extractability of radiocesium (as percent of total): water 2 = 0.3-1.1%; 1M CH 3 COONa = 0.3-0.9%; 0.04 M NH 4 Cl (in 25% CH 3 COOH) = 0.9-1.4% and 30% H 2 O 2 - 0.02 M HNO 3 = 4.5-9.0%.Specific radioactivity of the most efficiently bioaccumulating plant species did not exceed 4.0 BqKg -1 (dry weight biomass). These correspond to the soil-to-plant transfer factor (TF) values up to 44.4x10 -4 BqKg -1 crop, d.w.)/(BqKg -1 soil d.w). Aggregated transfer factor (T ag ) of the average sample of the whole crop harvested from defined area was 0.5x10 -5 (Bqkg -1 d.w. crop)/(Bqm -2 soil). It can be concluded that low mobility of radiocesium in analysed soil type, confirmed by sequential extraction analyses, is the main hindrance for practical application for autochthonous plants as a phytoremediation tool for aged contaminated area of non-cultivated sites. Plant cover can efficiently serve only as a soil surface-stabilising layer, mitigating the migration of radiocesium into the surrounding environment. (author)

Electrokinetic In Situ Treatment of Metal-Contaminated Soil

Science.gov (United States)

Quinn, Jacqueline; Clausen, Christian A., III; Geiger, Cherie; Reinhart, Debra

2004-01-01

An electrokinetic technique has been developed as a means of in situ remediation of soils, sludges, and sediments that are contaminated with heavy metals. Examples of common metal contaminants that can be removed by this technique include cadmium, chromium, zinc, lead, mercury, and radionuclides. Some organic contaminants can also be removed by this technique. In the electrokinetic technique, a low-intensity direct current is applied between electrodes that have been implanted in the ground on each side of a contaminated soil mass. The electric current causes electro-osmosis and migration of ions, thereby moving aqueous-phase subsurface contaminants from one electrode to the other. The half reaction at the anode yields H+, thereby generating an acid front that travels from the anode toward the cathode. As this acid front passes through a given location, the local increase in acidity increases the solubility of cations that were previously adsorbed on soil particles. Ions are transported towards one electrode or the other which one depending on their respective electric charges. Upon arrival at the electrodes, the ionic contaminants can be allowed to become deposited on the electrodes or can be extracted to a recovery system. Surfactants and other reagents can be introduced at the electrodes to enhance rates of removal of contaminants. Placements of electrodes and concentrations and rates of pumping of reagents can be adjusted to maximize efficiency. The basic concept of electrokinetic treatment of soil is not new. What is new here are some of the details of application and the utilization of this technique as an alternative to other techniques (e.g., flushing or bioremediation) that are not suitable for treating soils of low hydraulic conductivity. Another novel aspect is the use of this technique as a less expensive alternative to excavation: The cost advantage over excavation is especially large in settings in which contaminated soil lies near and/or under

Chelate-assisted phytoextraction of lead from contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Cooper, E.M.; Sims, J.T.; Cunningham, S.D.; Huang, J.W.; Berti, W.R.

1999-12-01

Phytoextraction, a remediation strategy for lead (Pb)-contaminated soils that removes soil Pb through plant uptake and harvest, may be enhanced by use of synthetic chelates. The authors evaluated Pb desorption from four contaminated soils by seven chelates (CDTA, DTPA, EDDHA, EFTA, HEDTA, HEIDA, and NTA) at three rates. The three most effective chelates (CDTA, DTPA, and HEDTA) were used in greenhouse studies with an uncontaminated soil and a Pb-contaminated soil to determine the effect of chelate type and rate on growth, Pb uptake, and plant elemental composition. Lead desorption varied with chelate and soil and increased with chelate rate, averaging 948 mg Pb kg{sup {minus}1} at the 20 mmol kg{sup {minus}1} rate vs. 28 mg Pb kg{sup {minus}1} by the control. The general ranking of chelate effectiveness, based on total Pb desorbed, was HEDTA > CDTA > DTPA > EGTA > HEIDA > EDDHA {approximately} NTA. Plant uptake of Pb from the contaminated soil was enhanced by CDTA, DTPA, and HEDTA, but with even the most effective treatment (corn, high CDTA rate), the amount of Pb extracted by plants was rather low. Lead extractable by the Toxicity Characteristic Leaching Procedure (TCLP) was increased from 9 mg L{sup {minus}1} in the control to from 47 to 174 mg L{sup {minus}1} in soils treated with 20 mmol kg{sup {minus}1} CDTA or DTPA and chelates generally caused a shift in Pb from resistant to more soluble chemical fractions.

Effective dielectric mixture model for characterization of diesel contaminated soil

International Nuclear Information System (INIS)

Al-Mattarneh, H.M.A.

2007-01-01

Human exposure to contaminated soil by diesel isomers can have serious health consequences like neurological diseases or cancer. The potential of dielectric measuring techniques for electromagnetic characterization of contaminated soils was investigated in this paper. The purpose of the research was to develop an empirical dielectric mixture model for soil hydrocarbon contamination application. The paper described the basic theory and elaborated in dielectric mixture theory. The analytical and empirical models were explained in simple algebraic formulas. The experimental study was then described with reference to materials, properties and experimental results. The results of the analytical models were also mathematically explained. The proposed semi-empirical model was also presented. According to the result of the electromagnetic properties of dry soil contaminated with diesel, the diesel presence had no significant effect on the electromagnetic properties of dry soil. It was concluded that diesel had no contribution to the soil electrical conductivity, which confirmed the nonconductive character of diesel. The results of diesel-contaminated soil at saturation condition indicated that both dielectric constant and loss factors of soil were decreased with increasing diesel content. 15 refs., 2 tabs., 9 figs

Bioremediation in soil contaminated with hydrocarbons in Colombia.

Directory of Open Access Journals (Sweden)

María Alejandra Trujillo Toro

2012-10-01

Full Text Available This study analyzes bioremediation processes of hydrocarbon contaminated soils in Colombia as a sustainable alternative to the deterioration of environmental quality by hydrocarbon spillage. According to national and international environmental law, all waste contaminated with hydrocarbons is considered dangerous waste, and therefore it cannot be released in the ground, water or be incinerated. Such legislation has motivated companies around the world to implement treatment processes for contaminated soils. Within Colombia, oil companies have been implementing the bioremediation of hydrocarbon contaminated soils in order to manage the waste coming from activities of oil drilling, refinement, transport and distribution.These practices must be considered viable for their ease of implementation, their low overhead costs, and for the benefits they provide towards environmental quality. Among the positive impacts that these practices have generated, it may consider the following: a solution for the problem of hydrocarbon contaminated soils, alternatives for the ultimate disposal of said waste without affecting ground, water or air resources, the low cost of the operation, and the technical experience of sustainable development which can continue to be implemented in companies dealing with dangerous waste.

Progress of research and utilization of soil amendments in phytoremediation of radioactive contamination soil

International Nuclear Information System (INIS)

Guo Yangrui; Song Gang; Chen Yongheng

2012-01-01

With the increasing of soil pollution and degradation, it becomes more important to research and apply soil amendments in agriculture. This paper reviewed different kinds of soil amendments and their impacts on phytostabilization and phytoextraction techniques, and summarized the application of soil amendments in the radio-contaminated soils as well as their effects on the phytoremediation. The main repair mechanisms of the soil amendments are involved in adsorption, ion exchange, chelation, and complexation. The potential applications in the phytoremediation on radio-contaminated soils, as well as the main repair mechanisms and the existing problems were discussed. (authors)

Vermiremediation of soils contaminated with mixture of petroleum ...

African Journals Online (AJOL)

In this paper, vermiremediation, a biological technique was utilized in order to clean-up soil contaminated with gasoline, diesel and spent engine oil using an earthworm - Eisenia fetida. The contaminated soils were analyzed for the total petroleum hydrocarbon (TPH) level every 24 hours over a period of 120 hours using ...

Fracture Toughness Evaluation of Space Shuttle External Tank Thermal Protection System Polyurethane Foam Insulation Materials

Science.gov (United States)

McGill, Preston; Wells, Doug; Morgan, Kristin

2006-01-01

Experimental evaluation of the basic fracture properties of Thermal Protection System (TPS) polyurethane foam insulation materials was conducted to validate the methodology used in estimating critical defect sizes in TPS applications on the Space Shuttle External Fuel Tank. The polyurethane foam found on the External Tank (ET) is manufactured by mixing liquid constituents and allowing them to react and expand upwards - a process which creates component cells that are generally elongated in the foam rise direction and gives rise to mechanical anisotropy. Similarly, the application of successive foam layers to the ET produces cohesive foam interfaces (knitlines) which may lead to local variations in mechanical properties. This study reports the fracture toughness of BX-265, NCFI 24-124, and PDL-1034 closed-cell polyurethane foam as a function of ambient and cryogenic temperatures and knitline/cellular orientation at ambient pressure.

Optimization of surfactant-aided remediation of industrially contaminated soils

International Nuclear Information System (INIS)

Joshi, M.M.; Lee, S.

1996-01-01

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 (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 shown to increase the removal efficiency several fold. For the present work, the removal of PAHs occurring in industrially contaminated soil was studied. The objective was to use a nonionic surfactant solution for in situ soil flushing and to evaluate the optimal range of process parameters that can significantly increase the removal efficiency. The process parameters chosen were surfactant concentration, ratio of washing solution volume to soil weight, and temperature of washing solution. These parameters were found to have a significant effect on PAH removal from the contaminated soil and an optimal range was determined for each parameter under given washing conditions

Heavy metal contamination of soil and sediment in Zambia

African Journals Online (AJOL)

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Key words: Heavy metal, contamination, mining, soil, sediment. INTRODUCTION ... drinking water and inhaling air or soil contaminated by mining activities and the ..... indicates that copper waste discharged into the upper reaches of the Kafue ...

External exposure from radionuclides in soil: analytical vs. simulation procedures

International Nuclear Information System (INIS)

Velasco, Hugo; Rizzotto, Marcos

2008-01-01

Full text: The external gamma irradiation resulting from radionuclides deposited on the ground surface can be an important source of radiation exposure. The assessment of this irradiation is extremely complex due to the large number of environmental factors which affect the gamma photon flux in air originating from the ground. The source energy affects the interaction between the radiation and the medium, and the characteristics and the properties of the soil are the most relevant factors to determine the energy and the angular distribution of gamma radiation in air 1 m above the ground surface. From an analytical point of view the calculations are based on the point-kernel integration method and assume that the source concentration at any depth in soil is uniform over an infinite surface parallel to the ground plane. The dose-rate factor is applied to environmental dose assessments by means of the general equation: H(t)= χ (t) x DRF where H is the external dose rate at time t, χ is the source concentration at the location of the exposed individual, and DRF is the dose-rate factor. Dose-rate factors in air at a height of 1 m above ground are tabulated for discrete photon energies between 0.01 and 10 MeV and for source depths in soil between 0 and 300 cm. These factors were determined for sources distributed in a slab of finite thickness and sources which are exponentially distributed with depth. A Monte Carlo algorithm was developed to simulate the gamma photons transport calculation for the soil/air configuration. In this case the soil constituents were assumed to be similar to those on the earth's crust. The model considers the gamma photons source distributed uniformly in the soil profile, from the ground surface to a depth beyond which the soil is considered uncontaminated. Source gamma photons were randomly selected from the contaminated soil zone and their subsequent interactions determined by the probability of occurrence via photoelectric effect, Compton

Soil contamination of plant surfaces from grazing and rainfall interactions

International Nuclear Information System (INIS)

Hinton, T.G.; Stoll, J.M.; Tobler, L.

1995-01-01

Contaminants often attach to soil particles, and their subsequent environmental transport is largely determined by processes that govern soil movement. We examined the influence of grazing intensity on soil contamination of pastures. Four different grazing densities of sheep were tested against an ungrazed control plot. Scandium concentrations were determined by neutron activation analysis and was used as a tracer of soil adhesion on vegetation. Soil loadings ( g soil kg -1 dry plant) increased 60% when grazing intensity was increased by a factor of four (p 0.003). Rain and wind removed soil from vegetation in the ungrazed control plots, but when grazing sheep were present, an increase in rain from 0.3 to 9.7 mm caused a 130% increase in soil contamination. Multiple regression was used to develop an equation that predicts soil loadings as a function of grazing density, rainfall and wind speed (p = 0.0001, r 2 = 0.78). The model predicts that if grazing management were to be used as a tool to reduce contaminant intake from inadvertent consumption of resuspended soil by grazing animals, grazing densities would have to be reduced 2.5 times to reduce soil loadings by 50%. (author)

Accelerated remediation of pesticide-contaminated soil with zerovalent iron

Energy Technology Data Exchange (ETDEWEB)

Shea, P.J. [University of Nebraska-Lincoln, Lincoln, NE 68583-0915 (United States)]. E-mail: pshea@unl.edu; Machacek, T.A. [University of Nebraska-Lincoln, Lincoln, NE 68583-0915 (United States); Comfort, S.D. [University of Nebraska-Lincoln, Lincoln, NE 68583-0915 (United States)

2004-11-01

High pesticide concentrations in soil from spills or discharges can result in point-source contamination of ground and surface waters. Cost-effective technologies are needed for on-site treatment that meet clean-up goals and restore soil function. Remediation is particularly challenging when a mixture of pesticides is present. Zerovalent iron (Fe{sup 0}) has been shown to promote reductive dechlorination and nitro group reduction of a wide range of contaminants in soil and water. We employed Fe{sup 0} for on-site treatment of soil containing >1000 mg metolachlor, >55 mg alachlor, >64 mg atrazine, >35 mg pendimethalin, and >10 mg chlorpyrifos kg{sup -1}. While concentrations were highly variable within the windrowed soil, treatment with 5% (w/w) Fe{sup 0} resulted in >60% destruction of the five pesticides within 90 d and increased to >90% when 2% (w/w) Al{sub 2}(SO{sub 4}){sub 3} was added to the Fe{sup 0}. GC/MS analysis confirmed dechlorination of metolachlor and alachlor during treatment. Our observations support the use of Fe{sup 0} for ex situ treatment of pesticide-contaminated soil. - Capsule: Zerovalent iron promotes pesticide degradation in highly contaminated soil.

Some aspects of remediation of contaminated soils

Science.gov (United States)

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

2014-05-01

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

External Tank Liquid Hydrogen (LH2) Prepress Regression Analysis Independent Review Technical Consultation Report

Science.gov (United States)

Parsons, Vickie s.

2009-01-01

The request to conduct an independent review of regression models, developed for determining the expected Launch Commit Criteria (LCC) External Tank (ET)-04 cycle count for the Space Shuttle ET tanking process, was submitted to the NASA Engineering and Safety Center NESC on September 20, 2005. The NESC team performed an independent review of regression models documented in Prepress Regression Analysis, Tom Clark and Angela Krenn, 10/27/05. This consultation consisted of a peer review by statistical experts of the proposed regression models provided in the Prepress Regression Analysis. This document is the consultation's final report.

Cathodic protection simulation of above ground storage tank bottom: Experimental and numerical results

Energy Technology Data Exchange (ETDEWEB)

Schultz, Marcelo [Inspection Department, Rio de Janeiro Refinery - REDUC, Petrobras, Rio de Janeiro (Brazil); Brasil, Simone L.D.C. [Chemistry School, Federal University of Rio de Janeiro, UFRJ, Rio de Janeiro (Brazil); Baptista, Walmar [Corrosion Department, Research Centre - CENPES, Petrobras (Brazil); Miranda, Luiz de [Materials and Metallurgical Engineering Program, COPPE, UFRJ, Rio de Janeiro (Brazil); Brito, Rosane F. [Corrosion Department, Research Centre, CENPES, Petrobras, Rio de Janeiro (Brazil)

2004-07-01

The deterioration history of Above ground Storage Tanks (AST) of Petrobras' refineries - shows that the great incidence of corrosion in the AST bottom is at the external side. This is a problem in the disposability of storage crude oil and other final products. At this refinery, all AST's are built over a concrete base with a lot of pile to support the structure and distribute the charge homogeneously. Because of this it is very difficult to use cathodic protection as an anti-corrosive method for each one of these tanks. This work presents an alternative cathodic protection system to protect the external side of the tank bottom using a new metallic bottom, placed at different distance from the original one. The space between the two bottoms was filled with one of two kinds of soils, sand or clay, more conductive than the concrete. Using a prototype tank it was studied the potential distributions over the new tank bottom for different system parameters, as soil resistivity, number and position of anodes localized in the old bottom. These experimental results were compared to numerical simulations, carried out using a software based on the Boundary Element Method. The computer simulation validates this protection method, confirming to be a very useful tool to define the optimized cathodic protection system configuration. (authors)

Allowable residual contamination levels of radionuclides in soil from pathway analysis

International Nuclear Information System (INIS)

Nyquist, J.E.; Baes, C.F. III

1987-01-01

The Remedial Action Program (RAP) at Oak Ridge National Laboratory will include well drilling, facility upgrades, and other waste management operations likely to involve soils contaminated with radionuclides. A preliminary protocol and generalized criteria for handling contaminated soils is needed to coordinate and plan RAP activities, but there exists only limited information on contaminate nature and distribution at ORNL RAP sites. Furthermore, projections of long-term decommissioning and closure options for these sites are preliminary. They have adapted a pathway analysis model, DECOM, to quantify risks to human health from radionuclides in soil and used it to outline preliminary criteria for determining the fate of contaminated soil produced during RAP activities. They assumed that the site could be available for unrestricted use immediately upon decontamination. The pathways considered are consumption of food grown on the contaminated soil, including direct ingestion of soil from poorly washed vegetables, direct radiation from the ground surface, inhalation of resuspended radioactive soil, and drinking water from a well drilled through or near the contaminated soil. We will discuss the assumptions and simplifications implicit in DECOM, the site-specific data required, and the results of initial calculations for the Oak Ridge Reservation

T-TY Tank Farm Interim Surface Barrier Demonstration - Vadose Zone Monitoring Plan

International Nuclear Information System (INIS)

Zhang, Z.F.; Strickland, Christopher E.; Field, Jim G.; Parker, Danny L.

2010-01-01

The Hanford Site has 149 underground single-shell tanks that store hazardous radioactive waste. Many of these tanks and their associated infrastructure (e.g., pipelines, diversion boxes) have leaked. Some of the leaked waste has entered the groundwater. The largest known leak occurred from the T-106 Tank of the 241-T Tank Farm in 1973. Five tanks are assumed to have leaked in the TY Farm. Many of the contaminants from those leaks still reside within the vadose zone within the T and TY Tank Farms. The Department of Energy's Office of River Protection seeks to minimize the movement of these contaminant plumes by placing interim barriers on the ground surface. Such barriers are expected to prevent infiltrating water from reaching the plumes and moving them further. The soil water regime is monitored to determine the effectiveness of the interim surface barriers. Soil-water content and water pressure are monitored using off-the-shelf equipment that can be installed by the hydraulic hammer technique. Four instrument nests were installed in the T Farm in fiscal year (FY) 2006 and FY2007; two nests were installed in the TY Farm in FY2010. Each instrument nest contains a neutron probe access tube, a capacitance probe, and four heat-dissipation units. A meteorological station has been installed at the north side of the fence of the T Farm. This document summarizes the monitoring methods, the instrument calibration and installation, and the vadose zone monitoring plan for interim barriers in T farm and TY Farm.

Uptake of Organic Contaminants from Soil into Vegetables and Fruits

DEFF Research Database (Denmark)

Trapp, Stefan; Legind, Charlotte Nielsen

2011-01-01

Contaminants may enter vegetables and fruits by several pathways: by uptake with soil pore water, by diffusion from soil or air, by deposition of soil or airborne particles, or by direct application. The contaminant-specific and plantspecific properties that determine the importance of these path......Contaminants may enter vegetables and fruits by several pathways: by uptake with soil pore water, by diffusion from soil or air, by deposition of soil or airborne particles, or by direct application. The contaminant-specific and plantspecific properties that determine the importance...... of these pathways are described in this chapter. A variety of models have been developed, specific for crop types and with steady-state or dynamic solutions. Model simulations can identify sensitive properties and relevant processes. Persistent, polar (log KOW ... particles, or from air. Volatile contaminants have a low potential for accumulation because they quickly escape to air. Experimental data are listed that support these model predictions, but underline also the high variability of accumulation under field conditions. Plant uptake predictions are uncertain...

Natural revegetation of hydrocarbon-contaminated soil in semi-arid grasslands

International Nuclear Information System (INIS)

Bizecki Robson, D.; Knight, J. D.; Farrell, R. E.; Germida, J. J.

2004-01-01

Phytoremediation, or the use of plants to degrade and contain soil contaminants is considered a cost-effective decontaminant for sites contaminated by spills in the oil and gas producing areas of Western Canada. The objective of this study was to determine if contamination by hydrocarbons changes soil properties, species composition, and species abundance when compared with uncontaminated plots, and to identify species and functional groups unique to contaminated sites that may be further screened for their hydrocarbon-degrading ability. In pursuit of these objectives the effect of contamination on coverage, litter and bare ground was examined, differences in species composition between contaminated and uncontaminated sites were assessed, and the ability to fix nitrogen, and form mycorrhiza, life form, pollination mode, seed dispersal and reproduction mode of each species was determined. Results showed less vegetation and litter cover in contaminated plots, and significantly higher soil carbon to nitrogen ratios. Species diversity was also lower on contaminated sites, although species richness was not significantly different. Self-pollinated species were significantly more common on contaminated sites. Five grasses and three forbs were identified as tolerant of hydrocarbon-contaminated soils, with two grasses -- Agropyron smithii, and Agropyron trachycaulum -- being the most promising for reclamation. The low vegetation cover on contaminated plots is attributed to high pH and carbon to nitrogen ratios, and low nitrogen and phosphorus that results from soil disturbance. High electrical conductivity is also considered to adversely affect vegetation and litter cover on contaminated sites. 54 refs., 3 tabs., 1 fig

Natural revegetation of hydrocarbon-contaminated soil in semi-arid grasslands

Energy Technology Data Exchange (ETDEWEB)

Bizecki Robson, D.; Knight, J. D.; Farrell, R. E.; Germida, J. J. [University of Saskatchewan, Dept. of Soil Science, Saskatoon, SK (Canada)

2004-01-01

Phytoremediation, or the use of plants to degrade and contain soil contaminants is considered a cost-effective decontaminant for sites contaminated by spills in the oil and gas producing areas of Western Canada. The objective of this study was to determine if contamination by hydrocarbons changes soil properties, species composition, and species abundance when compared with uncontaminated plots, and to identify species and functional groups unique to contaminated sites that may be further screened for their hydrocarbon-degrading ability. In pursuit of these objectives the effect of contamination on coverage, litter and bare ground was examined, differences in species composition between contaminated and uncontaminated sites were assessed, and the ability to fix nitrogen, and form mycorrhiza, life form, pollination mode, seed dispersal and reproduction mode of each species was determined. Results showed less vegetation and litter cover in contaminated plots, and significantly higher soil carbon to nitrogen ratios. Species diversity was also lower on contaminated sites, although species richness was not significantly different. Self-pollinated species were significantly more common on contaminated sites. Five grasses and three forbs were identified as tolerant of hydrocarbon-contaminated soils, with two grasses -- Agropyron smithii, and Agropyron trachycaulum -- being the most promising for reclamation. The low vegetation cover on contaminated plots is attributed to high pH and carbon to nitrogen ratios, and low nitrogen and phosphorus that results from soil disturbance. High electrical conductivity is also considered to adversely affect vegetation and litter cover on contaminated sites. 54 refs., 3 tabs., 1 fig.

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

Science.gov (United States)

Mucke, D.

2012-04-01

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

Remediation of a former tank farm : Saviktok Point, NWT

Energy Technology Data Exchange (ETDEWEB)

Gingras, P. [Biogenie Inc., Quebec City, PQ (Canada)

2008-07-01

A former tank farm was remediated in Saviktok Point, Northwest Territories (NWT). This presentation discussed the site characteristics and presented several photographs of the tank farm location. The remote location did not have any source of electrical power and was accessible only by sea. It had limited availability of equipment, materials and manpower. The preferred solution for the hydrocarbon contamination was biological treatment, which requires oxygen gas to maximize the degradation of contaminants. Other key aspects of biological treatment include the need for heat to sustain microbial activity; use of nitrogen and phosphorous; neutral pH and loose structure and moisture content. Several photographs were provided to illustrate treatment technologies; bench scale trials; and the use of wind turbines for soil aeration. A chart that demonstrated bioremediation efficiency at Saviktok Point was presented. The presentation revealed that over a 3 season period 17,000 cubic metres were treated to NWT industrial standards. The average temperatures during treatment was 30 degrees Celsius and soils were recycled as landfill cover material. The presentation concluded with a discussion Saviktok Point benefits, such as the minimization of soil handling; utilization of a wind-powered aeration system; adapted design of the biological treatment to site-specific conditions; and maximum use of local resources. figs.

Treatment of NORM contaminated soil from the oilfields.

Science.gov (United States)

Abdellah, W M; Al-Masri, M S

2014-03-01

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 μm to higher than 300 μm. 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. Copyright © 2013 Elsevier Ltd. All rights reserved.

Quicklime-induced changes of soil properties: Implications for enhanced remediation of volatile chlorinated hydrocarbon contaminated soils via mechanical soil aeration.

Science.gov (United States)

Ma, Yan; Dong, Binbin; He, Xiaosong; Shi, Yi; Xu, Mingyue; He, Xuwen; Du, Xiaoming; Li, Fasheng

2017-04-01

Mechanical soil aeration is used for soil remediation at sites contaminated by volatile organic compounds. However, the effectiveness of the method is limited by low soil temperature, high soil moisture, and high soil viscosity. Combined with mechanical soil aeration, quicklime has a practical application value related to reinforcement remediation and to its action in the remediation of soil contaminated with volatile organic compounds. In this study, the target pollutant was trichloroethylene, which is a volatile chlorinated hydrocarbon pollutant commonly found in contaminated soils. A restoration experiment was carried out, using a set of mechanical soil-aeration simulation tests, by adding quicklime (mass ratios of 3, 10, and 20%) to the contaminated soil. The results clearly indicate that quicklime changed the physical properties of the soil, which affected the environmental behaviour of trichloroethylene in the soil. The addition of CaO increased soil temperature and reduced soil moisture to improve the mass transfer of trichloroethylene. In addition, it improved the macroporous cumulative pore volume and average pore size, which increased soil permeability. As soil pH increased, the clay mineral content in the soils decreased, the cation exchange capacity and the redox potential decreased, and the removal of trichloroethylene from the soil was enhanced to a certain extent. After the addition of quicklime, the functional group COO of soil organic matter could interact with calcium ions, which increased soil polarity and promoted the removal of trichloroethylene. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pilot-scale bioremediation of a petroleum hydrocarbon-contaminated clayey soil from a sub-Arctic site

Energy Technology Data Exchange (ETDEWEB)

Akbari, Ali; Ghoshal, Subhasis, E-mail: subhasis.ghoshal@mcgill.ca

2014-09-15

Highlights: • Aeration and moisture addition alone caused extensive hydrocarbon biodegradation. • 30-day slurry reactor remediation endpoints attained in 385 days in biopiles. • High nitrogen concentrations inhibited hydrocarbon degradation. • Inhibition of biodegradation linked to lack of shifts in soil microbial community. - Abstract: Bioremediation is a potentially cost-effective solution for petroleum contamination in cold region sites. This study investigates the extent of biodegradation of petroleum hydrocarbons (C16–C34) in a pilot-scale biopile experiment conducted at 15 °C for periods up to 385 days, with a clayey soil, from a crude oil-impacted site in northern Canada. Although several studies on bioremediation of petroleum hydrocarbon-contaminated soils from cold region sites have been reported for coarse-textured, sandy soils, there are limited studies of bioremediation of petroleum contamination in fine-textured, clayey soils. Our results indicate that aeration and moisture addition was sufficient for achieving 47% biodegradation and an endpoint of 530 mg/kg for non-volatile (C16–C34) petroleum hydrocarbons. Nutrient amendment with 95 mg-N/kg showed no significant effect on biodegradation compared to a control system without nutrient but similar moisture content. In contrast, in a biopile amended with 1340 mg-N/kg, no statistically significant biodegradation of non-volatile fraction was detected. Terminal Restriction Fragment Length Polymorphism (T-RFLP) analyses of alkB and 16S rRNA genes revealed that inhibition of hydrocarbon biodegradation was associated with a lack of change in microbial community composition. Overall, our data suggests that biopiles are feasible for attaining the bioremediation endpoint in clayey soils. Despite the significantly lower biodegradation rate of 0.009 day{sup −1} in biopile tank compared to 0.11 day{sup −1} in slurry bioreactors for C16–C34 hydrocarbons, the biodegradation extents for this fraction

Restoration of contaminated soils; Restauracion de suelos contaminados

Energy Technology Data Exchange (ETDEWEB)

Miranda J, Jose Eduardo

2009-07-01

A great variety of techniques are used for the restoration of contaminated soils. The contamination is present by both organic and inorganic pollutants. Environmental conditions and soil characteristics should take into account in order to implement a remedial technique. The bioremediation technologies are showed as help to remove a variety of soil contaminants. (author) [Spanish] Una gran variedad de tecnicas son utilizadas para la restauracion de suelos contaminados. La contaminacion se presenta tanto por contaminantes organicos como inorganicos. Las condiciones ambientales y caracteristicas del suelo se deben de tomar en cuenta para poder implementar una tecnica remediadora. Las tecnologias de biorremediacion son mostradas como ayuda para remover una gran variedad de contaminantes del suelo. (autor)

Electromigration of Contaminated Soil by Electro-Bioremediation Technique

Science.gov (United States)

Azhar, A. T. S.; Nabila, A. T. A.; Nurshuhaila, M. S.; Shaylinda, M. Z. N.; Azim, M. A. M.

2016-07-01

Soil contamination with heavy metals poses major environmental and human health problems. This problem needs an efficient method and affordable technological solution such as electro-bioremediation technique. The electro-bioremediation technique used in this study is the combination of bacteria and electrokinetic process. The aim of this study is to investigate the effectiveness of Pseudomonas putida bacteria as a biodegradation agent to remediate contaminated soil. 5 kg of kaolin soil was spiked with 5 g of zinc oxide. During this process, the anode reservoir was filled with Pseudomonas putida while the cathode was filled with distilled water for 5 days at 50 V of electrical gradient. The X-Ray Fluorescent (XRF) test indicated that there was a significant reduction of zinc concentration for the soil near the anode with 89% percentage removal. The bacteria count is high near the anode which is 1.3x107 cfu/gww whereas the bacteria count at the middle and near the cathode was 5.0x106 cfu/gww and 8.0x106 cfu/gww respectively. The migration of ions to the opposite charge of electrodes during the electrokinetic process resulted from the reduction of zinc. The results obtained proved that the electro-bioremediation reduced the level of contaminants in the soil sample. Thus, the electro-bioremediation technique has the potential to be used in the treatment of contaminated soil.

Evaluation the Phytoremediation of Oil-contaminated Soils Around Isfahan Oil Refinery

Directory of Open Access Journals (Sweden)

Farida Iraji-Asiabadi

2016-07-01

Full Text Available Petroleum compounds are pollutants that most commonly occur in soils around oil refineries and that often find their ways into groundwater resources. Phytoremediation is a cost-effective alternative to physicochemical methods for oil-contaminated soil remediation, where feasible. In this study, a greenhouse experiment was conducted to evaluate the phytoremediation of oil-contaminated soils around Isfahan Oil Refinery. Four different plants (namely, sorghum, barley, agropyron, and festuca were initially evaluated in terms of their germinability in both contaminated and control (non-contaminated soils. Sorghum and barley (recording the highest germinability values were chosen as the species for use in the phytoremediation experiments. Shoot and root dry weights, total and oil-degrading bacteria counts, microbial activity, and total concentrations of petroleum hydrocarbons (TPHs were determined at harvest 120 days after planting. A significant difference was observed in the bacterial counts (total and oil-degrading bacteria between the planted soils and the control. In contaminated soils, a higher microbial activity was observed in the rhizosphere of the sorghum soil than in that of barley. TPHs concentration decreased by 52%‒64% after 120 days in contaminated soil in which sorghum and barley had been cultivated. This represented an improvement of 30% compared to the contaminated soil without plants. Based on the results obtained, sorghum and barley may be recommended for the removal of petro-contaminants in areas close to Isfahan Oil Refinery. Nevertheless, caution must be taken as such cultivated lands may need to be protected against grazing animals.

Selective flotation for the removal of radionuclides from contaminated soil

International Nuclear Information System (INIS)

Miller, J.D.; Yu, Q.; Lu, Y.Q.

1995-01-01

Low-level radioactive contaminated soils (10--500 pci/gm) created by defense-related activities at certain Superfund sites, such as Nevada Test Site (NTS), is a current environmental concern. Many of these contaminated sites may require appropriate cleanup and restoration, which could cost billions of dollars and put tremendous pressure on limited financial resources. Therefore, the development of a selective flotation process to separate such radionuclides from contaminated soils should be considered. In this study, both a pure depleted UO 2 sample and three synthetic UO 2 /soil mixtures were used to evaluate surface chemistry features and to examine the possibility for the flotation of fine UO 2 particles from selected soils. It was intended that this model system would be a reasonable representation of contaminated soils such as those found the Nevada Test Site which are reported to be contaminated by PuO 2 fallout. The effect of reagent schedule, particle size distribution, and surface charge are discussed with respect to the flotation separation of the UO 2 /soil mixtures. It was found that both commercial fatty acids and reagent grade sodium oleate are effective collectors for UO 2 flotation provided the pH is adjusted to the range of pH 8--9. The bench-scale flotation results successfully demonstrated that froth flotation technology can be used to remove UO 2 from such model contaminated soils with appropriate flotation chemistry conditions which depend on the soil characteristics and other pretreatment procedures

Plant tolerance to diesel minimizes its impact on soil microbial characteristics during rhizoremediation of diesel-contaminated soils

International Nuclear Information System (INIS)

Barrutia, O.; Garbisu, C.; Epelde, L.; Sampedro, M.C.; Goicolea, M.A.; Becerril, J.M.

2011-01-01

Soil contamination due to petroleum-derived products is an important environmental problem. We assessed the impacts of diesel oil on plants (Trifolium repens and Lolium perenne) and soil microbial community characteristics within the context of the rhizoremediation of contaminated soils. For this purpose, a diesel fuel spill on a grassland soil was simulated under pot conditions at a dose of 12,000 mg diesel kg -1 DW soil. Thirty days after diesel addition, T. repens (white clover) and L. perenne (perennial ryegrass) were sown in the pots and grown under greenhouse conditions (temperature 25/18 o C day/night, relative humidity 60/80% day/night and a photosynthetic photon flux density of 400 μmol photon m -2 s -1 ) for 5 months. A parallel set of unplanted pots was also included. Concentrations of n-alkanes in soil were determined as an indicator of diesel degradation. Seedling germination, plant growth, maximal photochemical efficiency of photosystem II (F v /F m ), pigment composition and lipophylic antioxidant content were determined to assess the impacts of diesel on the studied plants. Soil microbial community characteristics, such as enzyme and community-level physiological profiles, were also determined and used to calculate the soil quality index (SQI). The presence of plants had a stimulatory effect on soil microbial activity. L. perenne was far more tolerant to diesel contamination than T. repens. Diesel contamination affected soil microbial characteristics, although its impact was less pronounced in the rhizosphere of L. perenne. Rhizoremediation with T. repens and L. perenne resulted in a similar reduction of total n-alkanes concentration. However, values of the soil microbial parameters and the SQI showed that the more tolerant species (L. perenne) was able to better maintain its rhizosphere characteristics when growing in diesel-contaminated soil, suggesting a better soil health. We concluded that plant tolerance is of crucial importance for the

Remediation techniques for heavy metal-contaminated soils: Principles and applicability.

Science.gov (United States)

Liu, Lianwen; Li, Wei; Song, Weiping; Guo, Mingxin

2018-08-15

Globally there are over 20millionha of land contaminated by the heavy metal(loid)s As, Cd, Cr, Hg, Pb, Co, Cu, Ni, Zn, and Se, with the present soil concentrations higher than the geo-baseline or regulatory levels. In-situ and ex-situ remediation techniques have been developed to rectify the heavy metal-contaminated sites, including surface capping, encapsulation, landfilling, soil flushing, soil washing, electrokinetic extraction, stabilization, solidification, vitrification, phytoremediation, and bioremediation. These remediation techniques employ containment, extraction/removal, and immobilization mechanisms to reduce the contamination effects through physical, chemical, biological, electrical, and thermal remedy processes. These techniques demonstrate specific advantages, disadvantages, and applicability. In general, in-situ soil remediation is more cost-effective than ex-situ treatment, and contaminant removal/extraction is more favorable than immobilization and containment. Among the available soil remediation techniques, electrokinetic extraction, chemical stabilization, and phytoremediation are at the development stage, while the others have been practiced at full, field scales. Comprehensive assessment indicates that chemical stabilization serves as a temporary soil remediation technique, phytoremediation needs improvement in efficiency, surface capping and landfilling are applicable to small, serious-contamination sites, while solidification and vitrification are the last remediation option. The cost and duration of soil remediation are technique-dependent and site-specific, up to $500ton -1 soil (or $1500m -3 soil or $100m -2 land) and 15years. Treatability studies are crucial to selecting feasible techniques for a soil remediation project, with considerations of the type and degree of contamination, remediation goals, site characteristics, cost effectiveness, implementation time, and public acceptability. Copyright © 2018 Elsevier B.V. All rights

Leaching of Contamination from Stabilization/Solidification Remediated Soils of Different Texture

Science.gov (United States)

Burlakovs, Juris; Kasparinskis, Raimonds; Klavins, Maris

2012-09-01

Development of soil and groundwater remediation technologies is a matter of great importance to eliminate historically and currently contaminated sites. Stabilization/solidification (S/S) refers to binding of waste contaminants to a more chemically stable form and thus diminishing leaching of contamination. It can be performed using cement with or without additives in order to stabilize and solidify soil with the contamination in matrix. A series of experiments were done to determine leaching properties of spiked soils of different texture bound with cement. Results of experiments showed, that soil texture (content of sand, silt and clay particles) affects the leaching of heavy metals from stabilized soils.

Building 310 retention tanks characterization report

International Nuclear Information System (INIS)

Sholeen, C.M.; Geraghty, D.C.

1996-12-01

The Health Physics Section of ANL performed a characterization of the Building 310 Service Floor Retention Tank Facility during the months of July and August, 1996. The characterization included measurements for radioactivity, air sampling for airborne particles and sampling to determine the presence and quantity of hazardous materials requiring remediation. Copies of previous lead and asbestos sampling information was obtained from ESH-IH. The facility consists of ten retention tanks located in rooms, A-062A, A-050A, A-038A, A-026A, and an entry room A-068A which contained miscellaneous pumps and other scrap material. Significant contamination was found in each room except room A-068A which had two contaminated spots on the floor and a discarded contaminated pump. Room A-062A: This room had the highest radiation background. Therefore, beta readings reflected the background readings. The floor, west wall, and the exterior of tank No. 1 had areas of alpha contamination. The piping leading from the tank had elevated gamma readings. There were low levels of smearable contamination on the west wall-Room A-050A: Alpha and Beta contamination is wide spread on the floor, west wall and the lower portion of the north wall. An area near the electrical box on the west wall had alpha and beta loose contamination. The exterior of tank No. 4 also had contaminated areas. The grate in front of tank No. 4 was contaminated. The piping leading from tanks No. 2, 3, and 4 had elevated gamma readings. There were low levels of smearable contamination on tank No. 4 and on the tar paper that is glued to the floor

Degradation of tetraethyllead in leaded gasoline contaminated and uncontaminated soils

International Nuclear Information System (INIS)

Ou, L.; Jing, W.; Thomas, J.; Mulroy, P.

1995-01-01

For over 50 years, since its introduction in 1923 by General Motors, tetraethyllead (TEL) was the major antiknock agent used in leaded gasoline. Since the middle of 1970, use of leaded gasoline in automobiles was gradually phased out. The main objective of this study is to determine the degradation rates and metabolites of TEL in gasoline contaminated and uncontaminated soils. TEL in uncontaminated soils disappeared rapidly. Ionic triethyllead (TREL) was the major organolead metabolite in these soils, with ionic diethyllead (DEL) being the minor product. Nonsterile soils, but not autoclaved soils, had limited capacity to mineralize 14 C-TEL to 14 CO 2 , H 2 0, and Pb 2+ . Unlike TEL in uncontaminated soils, petroleum hydrocarbons protected TEL in leaded gasoline contaminated soils from being degraded. Both disappearance and mineralization rates of TEL in leaded gasoline contaminated soils decreased with the increase in gasoline concentration. It appears that TEL in leaded gasoline contaminated soils is relatively stable until the level of petroleum hydrocarbons falls below a critical value. TEL is then rapidly degraded. Hydrocarbon degrading microorganisms may be involved, to some extent, in the degradation of TEL

Hanford Tank 241-C-106: Impact of Cement Reactions on Release of Contaminants from Residual Waste

International Nuclear Information System (INIS)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Schaef, Herbert T.

2006-01-01

The CH2M HILL Hanford Group, Inc. (CH2M HILL) is producing risk/performance assessments to support the closure of single-shell tanks at the U.S. Department of Energy's Hanford Site. As part of this effort, staff at Pacific Northwest National Laboratory were asked to develop release models for contaminants of concern that are present in residual sludge remaining in tank 241-C-106 (C-106) after final retrieval of waste from the tank. Initial work to produce release models was conducted on residual tank sludge using pure water as the leaching agent. The results were reported in an earlier report. The decision has now been made to close the tanks after waste retrieval with a cementitious grout to minimize infiltration and maintain the physical integrity of the tanks. This report describes testing of the residual waste with a leaching solution that simulates the composition of water passing through the grout and contacting the residual waste at the bottom of the tank.

Uranium Phases in Contaminated Sediments Below Hanford's U Tank Farm

International Nuclear Information System (INIS)

Um, Wooyong; Wang, Zheming; Serne, R. Jeffrey; Williams, Benjamin D.; Brown, Christopher F.; Dodge, Cleveland J.; Francis, Arokiasamy J.

2009-01-01

Macroscopic and spectroscopic investigations (XAFS, XRF and TRLIF) on Hanford contaminated vadose zone sediments from the U-tank farm showed that U(VI) exists as different surface phases as a function of depth below ground surface (bgs). Dominant U(VI) silicate precipitates (boltwoodite and uranophane) were present in shallow-depth sediments (15-16 m bgs). In the intermediate depth sediments (20-25 m bgs), adsorbed U(VI) phases dominated but small amounts of surface precipitates consisting of polynuclear U(VI) surface complex were also identified. The deep depth sediments (> 28 m bgs) showed no signs of contact with tank wastes containing Hanford-derived U(VI), but natural uranium solid phases were observed. Most of the U(VI) was preferentially associated with the silt and clay size fractions and showed strong correlation with Ca, especially for the precipitated U(VI) silicate phase in the shallow depth sediments. Because U(VI) silicate precipitates dominate the U(VI) phases in the shallow depth sediments, macroscopic (bi)carbonate leaching should result in U(VI) releases from both desorption and dissolution processes. Having several different U(VI) surface phases in the Hanford contaminated sediments indicates that the U(VI) release mechanism could be complicated and that detailed characterization of the sediments would be needed to estimate U(VI) fate and transport in vadose zone

49 CFR 238.423 - Fuel tanks.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Fuel tanks. 238.423 Section 238.423 Transportation....423 Fuel tanks. (a) External fuel tanks. Each type of external fuel tank must be approved by FRA's Associate Administrator for Safety upon a showing that the fuel tank provides a level of safety at least...

49 CFR 229.217 - Fuel tank.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Fuel tank. 229.217 Section 229.217 Transportation... tank. (a) External fuel tanks. Locomotives equipped with external fuel tanks shall, at a minimum... to the fuel tank safety requirements of § 238.223 or § 238.423 of this chapter. The Director of the...

Levels of concern for radioactive contaminations in soil according to soil protection standards

International Nuclear Information System (INIS)

Gellermann, R.; Barkowski, D.; Machtolf, M.

2016-01-01

In the paper the question is examined whether the established soil protection standards for carcinogenic substances are also applicable to the assessment of radioactive soil contamination. Referring to the methods applied in soil protection for evaluation of dose-effectrelations and estimations of carcinogenic risks as well as the calculation methods for test values in soil protection ''levels of concern'' for soil contamination by artificial radionuclides are derived. The values obtained are significantly larger than the values for unrestricted clearance of ground according to the German Radiation Protection Ordinance (StrlSchV). The thesis that soil is protected according to environmental standards provided that radiation protection requirements are met needs further checks but can be probably confirmed if the radiation protection requirements are clearly defined.

Enrichment of arbuscular mycorrhizal fungi in a contaminated soil after rehabilitation.

Science.gov (United States)

Lopes Leal, Patrícia; Varón-López, Maryeimy; Gonçalves de Oliveira Prado, Isabelle; Valentim Dos Santos, Jessé; Fonsêca Sousa Soares, Cláudio Roberto; Siqueira, José Oswaldo; de Souza Moreira, Fatima Maria

Spore counts, species composition and richness of arbuscular mycorrhizal fungi, and soil glomalin contents were evaluated in a soil contaminated with Zn, Cu, Cd and Pb after rehabilitation by partial replacement of the contaminated soil with non-contaminated soil, and by Eucalyptus camaldulensis planting with and without Brachiaria decumbens sowing. These rehabilitation procedures were compared with soils from contaminated non-rehabilitated area and non-contaminated adjacent soils. Arbuscular mycorrhizal fungi communities attributes were assessed by direct field sampling, trap culture technique, and by glomalin contents estimate. Arbuscular mycorrhizal fungi was markedly favored by rehabilitation, and a total of 15 arbuscular mycorrhizal fungi morphotypes were detected in the studied area. Species from the Glomus and Acaulospora genera were the most common mycorrhizal fungi. Number of spores was increased by as much as 300-fold, and species richness almost doubled in areas rehabilitated by planting Eucalyptus in rows and sowing B. decumbens in inter-rows. Contents of heavy metals in the soil were negatively correlated with both species richness and glomalin contents. Introduction of B. decumbens together with Eucalyptus causes enrichment of arbuscular mycorrhizal fungi species and a more balanced community of arbuscular mycorrhizal fungi spores in contaminated soil. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

An overview of plutonium-238 decontamination and decommissioning (D and D) projects at Mound

International Nuclear Information System (INIS)

Bond, W.H.; Davis, W.P.; Draper, D.G.; Geichman, J.R.; Harris, J.C.; Jaeger, R.R.; Sohn, R.L.

1987-01-01

Mound is currently decontaminating for restricted reuse and/or decommissioning for conditional release four major plutonium-238 contaminated facilities that contained 1700 linear feet of gloveboxes and associated equipment and services. Several thousand linear feet of external underground piping, associated tanks, and contaminated soil are being removed. Two of the facilities contain ongoing operations and will be reused for both radioactive and nonradioactive programs. Two others will be completely demolished and the land area will become available for future DOE building sites. An overview of the successful techniques and equipment used in the decontamination and decommissioning of individual pieces of equipment, gloveboxes, services, laboratories, sections of buildings, entire buildings, and external underground piping, tanks, and soil in a highly populated residential area is described and pictorially presented

Clean-up criteria for remediation of contaminated soils

International Nuclear Information System (INIS)

Nguyen, H.D.; Wilson, J.R.; Sato, Chikashi

1997-01-01

'How clean is clean?' is a question commonly raised in the remediation of contaminated soils. To help with the answer, criteria are proposed to serve as guidelines for remedial actions and to define a clean-up level such that the remaining contaminant residuals in the soil will not violate the Drinking Water Standards (DWS). The equations for computing those criteria are developed from the principle of conservation of mass and are functions of the maximum concentration level in the water (MCL) and the sorption coefficient. A multiplier, ranging from 10 to 1000, is also factored into the soil standard equation to reflect the effectiveness of various remediation techniques. Maximum allowable concentration in the soil (MSCL) is presented for several contaminants which are being regulated at the present time. Future modifications are recommended for better estimates of the MSCLs as additional transport mechanisms are incorporated to account for other potentially dominant effects

Managing long-term polycyclic aromatic hydrocarbon contaminated soils: a risk-based approach.

Science.gov (United States)

Duan, Luchun; Naidu, Ravi; Thavamani, Palanisami; Meaklim, Jean; Megharaj, Mallavarapu

2015-06-01

Polycyclic aromatic hydrocarbons (PAHs) are a family of contaminants that consist of two or more aromatic rings fused together. Soils contaminated with PAHs pose significant risk to human and ecological health. Over the last 50 years, significant research has been directed towards the cleanup of PAH-contaminated soils to background level. However, this achieved only limited success especially with high molecular weight compounds. Notably, during the last 5-10 years, the approach to remediate PAH-contaminated soils has changed considerably. A risk-based prioritization of remediation interventions has become a valuable step in the management of contaminated sites. The hydrophobicity of PAHs underlines that their phase distribution in soil is strongly influenced by factors such as soil properties and ageing of PAHs within the soil. A risk-based approach recognizes that exposure and environmental effects of PAHs are not directly related to the commonly measured total chemical concentration. Thus, a bioavailability-based assessment using a combination of chemical analysis with toxicological assays and nonexhaustive extraction technique would serve as a valuable tool in risk-based approach for remediation of PAH-contaminated soils. In this paper, the fate and availability of PAHs in contaminated soils and their relevance to risk-based management of long-term contaminated soils are reviewed. This review may serve as guidance for the use of site-specific risk-based management methods.

A Test Study to Display Buried Anti-Tank Landmines with GPR and Research Soil Characteristics with CRS

Science.gov (United States)

Kadioglu, Selma; Kagan Kadioglu, Yusuf

2014-05-01

An anti-tank mine (AT mine) is a type of land mine designed to damage or destroy vehicles including tanks and armored fighting vehicles. Anti-tank mines typically have a much larger explosive charge, and a fuze designed only to be triggered by vehicles or, in some cases, tampering with the mine. There are a lot of AT mine types. In our test study, MK4 and MK5 AT mine types has been used. The Mk 5 was a cylindrical metal cased U.K. anti-tank blast mine that entered service in 1943, during the Second World War. General Specifications of them are 203 mm diameter, 127 mm height, 4.4-5.7 kg weight, 2.05-3.75 kg of TNT explosive content and 350 lbs operating pressure respectively. The aims of the test study were to image anti-tank landmine with GPR method and to analyse the soil characteristics before the mines made explode and after made be exploded and determine changing of the soil characteristics. We realized data measurement on the real 6 unexploded anti-tank landmine buried approximately 15 cm in depth. The mines spaced 3 m were buried in two lines. Space between lines was 1.5 m. We gathered data on the profiles, approximately 7 m, with a Ramac CUII system and 800 MHz shielded antenna. We collected soil samples on the mines, near and around the mines, on the area in village. We collected soil samples before exploding and after exploding mines. We imaged anti-tank landmines on the depth slices of the GPR data and in their interactive transparent 3D subsets successfully. We used polarized microscope and confocal Raman spectroscopy (CRS) to identify soil characteristic before and after exploitation. The results presented that GPR method and its 3D imaging were successful to determine AT mines, and there was no important changing on mineralogical and petrographical characterization of the soil before and after exploding processing. This project has been supported by Ankara University under grant no 11B6055002. The study is a contribution to the EU funded COST action TU

Soil microbial effects of smelter induced heavy metal contamination

Energy Technology Data Exchange (ETDEWEB)

Nordgren, A

1986-01-01

The soil concentrations of Cu and Zn at the secondary smelter were 20 00 mu g/g dry soil. Close to the primary smelter the soil was contaminated with more than ten elements including Pb, Zn, Cu and As at levels ranging between 6000 and 1000 mu g/g dry soil. The correlations between the concentrations of the metals were high at both smelters. Soil respiration rate decreased by about 75% close to both smelters. Total and fluorescein diacetate stained mycelial lengths decrease with increasing heavy metal pollution at the secondary but not at the primary smelter. The fungal community structure was strongly affected by the contamination. General common in coniferous forest soils such as Penicillium and Oidiodendron virtually vanished, while less frequent species like Paecilomyces farinosus and Geomyces pannorum dominated the site close to the smelter. Colony forming units of a number of functional groups of bacteria were found to be very sensitive to metal contamination. The urease activity of the soil was inhibited. Multivariate statistical analyses showed that the metal contamination was the major environmental influence on the microbiotain the soils studied. A study of about 200 decomposition curves resulting from glutamic acid additions to the different soils produced four microbially related parameters: basal respiration rate, initial respiration rate after the addition of the glutamic acid, specific respiration rate during the exponential increase of the respiration rate and the lag time before the exponential phase. With 53 refs.

Waste management of actinide contaminated soil

International Nuclear Information System (INIS)

Navratil, J.D.; Thompson, G.H.; Kochen, R.L.

1978-01-01

Waste management processes have been developed to reduce the volume of Rocky Flats soil contaminated with plutonium and americium and to prepare the contaminated fraction for terminal storage. The primary process consists of wet-screening. The secondary process uses attrition scrubbing and wet screening with additives. The tertiary process involves volume reduction of the contaminated fraction by calcination, or fixation by conversion to glass. The results of laboratory scale testing of the processes are described

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

Science.gov (United States)

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

2009-01-01

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

In situ vadose zone remediation of petroleum-contaminated soils

International Nuclear Information System (INIS)

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

1991-01-01

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

Soil structure interaction analysis of buried tank subjected to vertical excitations

International Nuclear Information System (INIS)

Wong, C.K.; Stine, M.; Wagenblast, G.; Farnworth, S.

1995-09-01

Underground High Level Waste Storage Tanks are subjected to strigent seismic requirements At some DOE sites, many existing waste storage tanks are of the double-shell tank design. In this configuration, the concrete outer structure acts as the vault and provides secondary confinement for the primary steel waste storage tank. To ensure the safety of the design and a good understanding of the seismic response of the concrete confinement structure, seismic analysis, including the effects of Soil-Structure Interaction (SSI), is generally performed with special purpose SSI computer analysis programs. Generally, the seismic SSI response due to vertical excitation is considered to be secondary to those of the horizontal excitation. In this paper, a detailed evaluation of the SSI response due to vertical excitation is presented and is shown to merit equal consideration relative to the horizontal excitation. The geometry and relative dimensions (i.e. flexibility) of the structure can have significant influence on the vertical seismic SSI response in local region(s) of the concrete structure

Investigation of elemental and radiological contamination of soils in two shipyards in Chittagong, Bangladesh

International Nuclear Information System (INIS)

Uddin, M. Shuza; Shariff, M. Asad; Hasan, M. Mehedi

2014-01-01

An analysis of metallic elements and natural radioactivity in soils collected from two shipyards and their surroundings in Chittagong, Bangladesh is presented. The elemental concentrations of the metals Cr, Mn, Fe, Ni and Cu were obtained by PIXE analysis with a 3 MV Tandem Accelerator, and the radioactivity of 226 Ra, 232 Th and 40 K was determined using HPGe gamma-ray spectrometry. From the mean specific activities of the three radionuclides in soil samples, the radium equivalent activity, the gamma absorbed dose rate, the annual effective dose rate and the external hazard index were calculated. The study was focused on investigation of soil contamination via shipbreaking activities, if any. The somewhat higher contents of Cr, Mn, Fe, Ni and Cu in soil samples of shipyards, as compared to other locations, seem to be caused by the shipbreaking activities. The specific radioactivities as well as radium equivalent activity in soils of shipyards are also higher and thus possibly an indirect result of shipbreaking activities.

Investigation of elemental and radiological contamination of soils in two shipyards in Chittagong, Bangladesh

Energy Technology Data Exchange (ETDEWEB)

Uddin, M. Shuza; Shariff, M. Asad; Hasan, M. Mehedi [Tandem Accelerator Facility, Dhaka (Bangladesh). Inst. of Nuclear Science and Technology, Atomic Energy Research Establishment; Barua, Bijoy Sonker [Tandem Accelerator Facility, Dhaka (Bangladesh). Inst. of Nuclear Science and Technology, Atomic Energy Research Establishment; Chittagong Univ. of Engineering and Technology, Chittagong (Bangladesh). Dept. of Physics; Rashid, M. Abdur [Chittagong Univ. of Engineering and Technology, Chittagong (Bangladesh). Dept. of Physics; Kamal, Masud [Radioactivity Testing and Monitoring Lab. Bangladesh Atomic Energy Commission, Chittagong (Bangladesh)

2014-10-01

An analysis of metallic elements and natural radioactivity in soils collected from two shipyards and their surroundings in Chittagong, Bangladesh is presented. The elemental concentrations of the metals Cr, Mn, Fe, Ni and Cu were obtained by PIXE analysis with a 3 MV Tandem Accelerator, and the radioactivity of {sup 226}Ra, {sup 232}Th and {sup 40}K was determined using HPGe gamma-ray spectrometry. From the mean specific activities of the three radionuclides in soil samples, the radium equivalent activity, the gamma absorbed dose rate, the annual effective dose rate and the external hazard index were calculated. The study was focused on investigation of soil contamination via shipbreaking activities, if any. The somewhat higher contents of Cr, Mn, Fe, Ni and Cu in soil samples of shipyards, as compared to other locations, seem to be caused by the shipbreaking activities. The specific radioactivities as well as radium equivalent activity in soils of shipyards are also higher and thus possibly an indirect result of shipbreaking activities.

Remediation of Cd-contaminated soil around metal sulfide mines

Science.gov (United States)

Lu, Xinzhe; Hu, Xuefeng; Kang, Zhanjun; Luo, Fan

2017-04-01

The mines of metal sulfides are widely distributed in the southwestern part of Zhejiang Province, Southeast China. The activities of mining, however, often lead to the severe pollution of heavy metals in soils, especially Cd contamination. According to our field investigations, the spatial distribution of Cd-contaminated soils is highly consistent with the presence of metal sulfide mines in the areas, further proving that the mining activities are responsible for Cd accumulation in the soils. To study the remediation of Cd-contaminated soils, a paddy field nearby large sulfide mines, with soil pH 6 and Cd more than 1.56 mg kg-1, five times higher than the national recommended threshold, was selected. Plastic boards were deeply inserted into soil to separate the field and make experimental plots, with each plot being 4 m×4 m. Six treatments, TK01˜TK06, were designed to study the effects of different experimental materials on remediating Cd-contaminated soils. The treatment of TK01 was the addition of 100 kg zeolites to the plot; TK02, 100 kg apatites; TK03, 100 kg humid manure; TK04, 50 kg zeolites + 50 kg apatites; TK05, 50 kg zeolites + 50 kg humid manure; TK06 was blank control (CK). One month after the treatments, soil samples at the plots were collected to study the possible change of chemical forms of Cd in the soils. The results indicated that these treatments reduced the content of available Cd in the soils effectively, by a decreasing sequence of TK04 (33%) > TK02 (25%) > TK01 (23%) > TK05 (22%) > TK03 (15%), on the basis of CK. Correspondingly, the treatments also reduced the content of Cd in rice grains significantly, by a similar decreasing sequence of TK04 (83%) > TK02 (77%) > TK05 (63%) > TK01 (47%) > TK03 (27%). The content of Cd in the rice grains was 0.071 mg kg-1, 0.094 mg kg-1, 0.159 mg kg-1, 0.22 mg kg-1 and 0.306 mg kg-1, respectively, compared with CK, 0.418 mg kg-1. This experiment suggested that the reduction of available Cd in the soils is