WorldWideScience

Sample records for assessing contaminant attenuation

  1. Long-term assessment of natural attenuation: statistical approach on soils with aged PAH-contamination

    OpenAIRE

    Schwartz, Christophe; CHENOT, Elodie-Denise; Masfaraud, Jean-Francois; Ouvrard, Stéphanie

    2012-01-01

    Natural attenuation processes valorization for PAH-contaminated soil remediation has gained increasing interest from site owners. Indeed, far from the “do nothing; Nature will take rid of the problem” image, monitored natural attenuation (MNA) offers a valuable, cheaper and environmentally friendly alternative to more classical options such as physicochemical treatments (e.g. chemical oxidation, thermal desorption). The still refractory attitude of regulatory authorities and st...

  2. Use of stable carbon isotope analysis to assess natural attenuation of organic contaminants in the unsaturated zone

    International Nuclear Information System (INIS)

    Introduction Natural attenuation is an attractive remediation strategy when dealing with petroleum-hydrocarbon contaminated sites because of its cost efficiency. The unsaturated zone can play an important role in regulating the contaminant transfer between soil and groundwater. On one hand, contaminants from the soil zone may be degraded in the unsaturated zone thus preventing groundwater contamination. On the other hand, contaminants diffusing from the subsurface towards the atmosphere may be eliminated before reaching potential targets. Biodegradation is usually the main process leading to contaminant destruction and is usually considered to be the only process to influence 13C/12C ratio of organic contaminants in the saturated zone. Therefore, carbon and hydrogen isotope analysis has been used as a tool to demonstrate biodegradation (Griebler et al. 2004, Steinbach et al. 2004). Carbon and hydrogen isotope fractionation occurs during biodegradation as a consequence of the slightly faster cleavage of chemical bonds between light isotopes of an element compared to heavy isotopes. The difference in degradation rates leads to an enrichment of the heavy isotopes in the residual contaminant pool compared to the initial value. Most of the field studies focused on the saturated zone (Meckenstock et al. 2004) compare to only few studies on the unsaturated zone (Kirtland et al. 2005, Stehmeier et al. 1999). The aim of this study was to evaluate whether compound-specific stable isotope analysis can be used to demonstrate biodegradation of petroleum hydrocarbons in the unsaturated zone. The study included a field experiment and mathematical simulations. At the field site, a defined mixture of hydrocarbons was buried in a sandy unsaturated zone and the evolution of concentration and isotope ratios of various hydrocarbons was followed using a dense network of sampling points. The study was complemented with two mathematical simulations performed to gain insight into the

  3. Assessment of the biostimulation against bioaugmentation and natural attenuation on contaminated soil with diesel-gasoline mixing

    International Nuclear Information System (INIS)

    In this study carried out the bioremediation of a contaminated soil with a gasoline-diesel fuel mixture in a laboratory scale, to evaluate biostimulation against natural attenuation and bioaugmentation. The reduction of Total Petroleum Hydrocarbons (TPH) concentration during three months was 52.79 % for natural attenuation, 60.45 % for biostimulation and 64.92 % for bioaugmentation. For the inoculation in the bioaugmentation treatment, was isolated a bacterium with the capacity of degrade hydrocarbons which was identified as Bacillus sp.

  4. Coupling of Realistic Rate Estimates with Genomics for Assessing Contaminant Attenuation and Long-Term Plume Containment

    Energy Technology Data Exchange (ETDEWEB)

    Colwell, F. S.; Crawford, R. L.; Sorenson, K.

    2005-09-01

    Acceptance of monitored natural attenuation (MNA) as a preferred treatment technology saves significant site restoration costs for DOE. However, in order to be accepted MNA requires direct evidence of which processes are responsible for the contaminant loss and also the rates of the contaminant loss. Our proposal aims to: 1) provide evidence for one example of MNA, namely the disappearance of the dissolved trichloroethylene (TCE) from the Snake River Plain aquifer (SRPA) at the Idaho National Laboratory’s Test Area North (TAN) site, 2) determine the rates at which aquifer microbes can co-metabolize TCE, and 3) determine whether there are other examples of natural attenuation of chlorinated solvents occurring at DOE sites. To this end, our research has several objectives. First, we have conducted studies to characterize the microbial processes that are likely responsible for the co-metabolic destruction of TCE in the aquifer at TAN (University of Idaho and INL). Second, we are investigating realistic rates of TCE co-metabolism at the low catabolic activities typical of microorganisms existing under aquifer conditions (INL). Using the co-metabolism rate parameters derived in low-growth bioreactors, we will complete the models that predict the time until background levels of TCE are attained in the aquifer at TAN and validate the long-term stewardship of this plume. Coupled with the research on low catabolic activities of co-metabolic microbes we are determining the patterns of functional gene expression by these cells, patterns that may be used to diagnose the co-metabolic activity in the SRPA or other aquifers. Third, we have systematically considered the aquifer contaminants at different locations in plumes at other DOE sites in order to determine whether MNA is a broadly applicable remediation strategy for chlorinated hydrocarbons (North Wind Inc.). Realistic terms for co-metabolism of TCE will provide marked improvements in DOE’s ability to predict and

  5. Coupling of Realistic Rate Estimates with Genomics for Assessing Contaminant Attenuation and Long-Term Plume Containment

    Energy Technology Data Exchange (ETDEWEB)

    Colwell, F.S.; Crawford, R.L.; Sorenson, K.

    2005-09-01

    Acceptance of monitored natural attenuation (MNA) as a preferred treatment technology saves significant site restoration costs for DOE. However, in order to be accepted MNA requires direct evidence of which processes are responsible for the contaminant loss and also the rates of the contaminant loss. Our proposal aims to: 1) provide evidence for one example of MNA, namely the disappearance of the dissolved trichloroethylene (TCE) from the Snake River Plain aquifer (SRPA) at the Idaho National Laboratory’s Test Area North (TAN) site, 2) determine the rates at which aquifer microbes can co-metabolize TCE, and 3) determine whether there are other examples of natural attenuation of chlorinated solvents occurring at DOE sites. To this end, our research has several objectives. First, we have conducted studies to characterize the microbial processes that are likely responsible for the co-metabolic destruction of TCE in the aquifer at TAN (University of Idaho and INL). Second, we are investigating realistic rates of TCE co-metabolism at the low catabolic activities typical of microorganisms existing under aquifer conditions (INL). Using the co-metabolism rate parameters derived in low-growth bioreactors, we will complete the models that predict the time until background levels of TCE are attained in the aquifer at TAN and validate the long-term stewardship of this plume. Coupled with the research on low catabolic activities of co-metabolic microbes we are determining the patterns of functional gene expression by these cells, patterns that may be used to diagnose the co-metabolic activity in the SRPA or other aquifers.

  6. Applicability of monitored natural attenuation at radioactively contaminated sites

    International Nuclear Information System (INIS)

    The IAEA attaches great importance to the dissemination of information that can assist Member States with the development, implementation, maintenance and continuous improvement of systems, programmes and activities that support a sustainable nuclear fuel cycle and nuclear applications, including managing the legacy of past practices and accidents. Hence, the IAEA has initiated a comprehensive programme of work covering all aspects of environmental remediation including: - Technical and non-technical factors influencing decision making in environmental remediation; - Site characterization techniques and strategies; - Assessment of remediation technologies; - Assessment of technical options for cleanup of contaminated media; - Post-restoration compliance monitoring; - Assessment of the costs of remediation measures. It has been observed that many measures to remove or contain contamination are inefficient below certain concentrations, in general costly, and of a limited lifetime compared with the half-lives of the radionuclides concerned. Dispersed low level contamination poses a particular challenge to those charged with its remediation. Economic considerations in many Member States also result in constraints being placed on resources available to deal with such contamination. Experience has also shown that many techniques are not efficient below certain concentration thresholds or may entail impacts on certain environmental compartments in addition to those due to the contamination itself. This includes doses received by workers on the remediation project. As a result, the concept of relying on geological media to retain contaminants and/or to 'flatten out' concentration/dose peaks is increasingly being discussed in a remediation context. Technical Reports Series No. 424 (Remediation of Sites with Dispersed Radioactive Contamination) examined a variety of technological options for remediating dispersed contamination and concluded that the approaches can be broadly

  7. Attenuation of Selected Emerging Contaminants During River Transport

    Science.gov (United States)

    Reinhard, M.; Gross, B.; Hadeler, A.

    2002-12-01

    The ubiquitous occurrence of emerging (non-regulated) contaminants in the aquatic environment is of concern because some of these chemicals are biologically active at low concentrations and a potential threat to wildlife and human health.. Emerging contaminants include a diverse range of chemicals, including pharmaceuticals, natural and synthetic hormones and industrial surfactants, such as alkylphenol ethoxylates (APEO) and their metabolites. To address the ecotoxicological impact of these chemicals, it is necessary to know their sources, removal efficiencies during wastewater treatment, and their behavior in the environment. In this study, the fate of selected emerging contaminants in the Santa Ana River (SAR) in Southern California was investigated. The SAR originates in the San Bernardino Mountains and flows 80 miles into the Pacific Ocean. The SAR flow stems mainly from storm runoff, wastewater treatment effluents and several other minor sources. During the dry season, SAR flow is dominated by effluent from public wastewater treatment plants. Input into the SAR was studied by analyzing samples from four major treatment plants that employ different tertiary treatment processes. To assess the fate during river water transport and during wetland treatment, samples from six sites along the river were analyzed. Effluent samples were analyzed every two months, river water every four months. River samples were taken considering the flow velocity, which is approximately 1 mile per hour. The analytical method involves solid-phase extraction using C-18 cartridges and extraction of three fractions. Samples were analyzed with and without further derivatization using GC/MS and GC/MS/MS. Results indicate significant contaminant removal during river transport, presumably by photochemical oxidation. Within a distance of nine miles, pharmaceuticals, plasticizers, flame retardants, APEOs and metabolites were attenuated with removal rates ranging from 76% for a flame retardant

  8. Coupling of Realistic Rate Estimates with Genomics for Assessing Contaminant Attenuation and Long-Term Plume Containment - Task 4: Modeling - Final Report

    International Nuclear Information System (INIS)

    Trichloroethene (TCE), a common groundwater contaminant, can be degraded under certain conditions by microorganisms that occur naturally in the subsurface. TCE can be degraded under anaerobic conditions to less chlorinated compounds and ultimately into the non-chlorinated, non-hazardous end product, ethene, via anaerobic reductive dechlorination (ARD). ARD is widely recognized as a TCE degradation mechanism, and occurs in active groundwater remediation and can occur during monitored natural attenuation (MNA). MNA relies on natural processes, such as dispersion and degradation, to reduce contaminant concentrations to acceptable levels without active human intervention other than monitoring. TCE can also be biodegraded under aerobic conditions via cometabolism, in which microbial enzymes produced for other purposes fortuitously also react with TCE. In cometabolism, TCE is oxidized directly to non-hazardous products. Cometabolism as a TCE-degrading process under aerobic conditions is less well known than ARD. Natural attenuation is often discounted as a TCE remedial alternative in aerobic conditions based on the paradigm that TCE is biodegradable only under anaerobic conditions. In contrast to this paradigm, TCE was shown to degrade relative to conservative co-contaminants at an environmentally significant rate in a large (approximately 3 km long) TCE plume in aerobic groundwater at the Idaho National Laboratory (INL), and the degradation mechanism was shown to be cometabolism. MNA was selected as the remedy for most of this plume, resulting in a considerable cost savings relative to conventional remedial methods. To determine if cometabolism might be a viable remedy at other sites with TCE-contaminated aerobic groundwater, TCE plumes at Department of Energy (DOE) facilities were screened to evaluate whether TCE commonly degrades in aerobic groundwater, and if degradation rates are fast enough that natural attenuation could be a viable remedy. One hundred and twenty

  9. Consideration of natural attenuation. In remedation contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-04-15

    Upon the proposal submitted by ist Standing committee 5 (Contaminated Sites Committee - ALA) the Federal / State Working Group on Soil protection employed an ad hoc subcommittee dealing with considering natural attenuation in remediating contaminated sites and preparing an inter-State position paper. In the present position paper the way how to consider natural attenuation in practical remediation of contaminated sites is described. The systematic approach outlined allows an understandable decision-finding. A way is shown how the competent soil protection authorities may exercise discretion and in the framework of checking the appropriateness of measures may decide on the implementation of MNA based on a MNA concept (MNA = monitored natural attenuation). It is, however, also explained that when carrying out MNA a decision always made in an individual case is concerned which should be made in a close agreement between the obligated party and the authority.

  10. Natural attenuation of diesel aliphatic hydrocarbons in contaminated agricultural soil

    International Nuclear Information System (INIS)

    A diesel fuel spill at a concentration of 1 L m-2 soil was simulated on a 12 m2 plot of agricultural land, and natural attenuation of aliphatic hydrocarbons was monitored over a period of 400 days following the spill after which the aliphatic hydrocarbon concentrations were found to be below the legal contamination threshold for soil. The main fraction of these compounds (95%) remained at the surface layer (0-10 cm). Shortly after the spill (viz. between days 0 and 18), evaporation was the main origin of the dramatic decrease in pollutant concentrations in the soil. Thereafter, soil microorganisms used aliphatic hydrocarbons as sources of carbon and energy, as confirmed by the degradation ratios found. Soil quality indicators, soil microbial biomass and dehydrogenase activity, regained their original levels about 200 days after the spill. - The effect of aliphatic hydrocarbons contamination on soil quality was monitored over a period of 400 days after a Diesel fuel spill

  11. 某石化污染场地含水层自然降解BTEX能力评估%The Assessment of Aquifer Natural Attenuation(BTEX)Capacity in a Petrochemical Contaminated Site

    Institute of Scientific and Technical Information of China (English)

    蔡婧怡; 陈宗宇; 蔡五田; 高宗军; 张敏

    2015-01-01

    Groundwater pollution is one of the important environmental issues concerned in China.Monitoring and assessing natural attenuation capacity of an aquifer is not only a basic means for preventing and treating groundwater pollution,but also a hot topic in groundwater remediation technology research in abroad.In this paper,authors,taking a petrochemical site in North China Plain as a case study,estimate the aquifer natural attenuation amount of BTEX per year using microbial hydrogeological and chemical method,based on investiga-tion of hydrogeological condition and pollution status in soil and groundwater as well as monitoring of BTEX con-centration and some related chemical parameters in groundwater.This research result provides an empirical and basic data for assessment of natural attenuation capacity of petroleum contaminated sites in China.%地下水污染问题是国家关注的重要环境问题之一,监测与评估含水层自然降解污染物能力是防治地下水污染的基本手段,也是国外地下水中修复技术研究热点课题。以华北平原某石油化工类场地为案例,通过调查场地水文地质条件、土壤及地下水污染现状,监测场地地下水中苯系物(BTEX)浓度及相关化学参数变化,运用微生物水文地球化学方法和水文地质方法,估算了该场地含水层自然降解苯系物量。这一研究成果为评估我国石油类场地地下水污染的自然修复能力提供了实证和基础数据。

  12. Attenuation of contaminants of emerging concern during surface-spreading aquifer recharge.

    Science.gov (United States)

    Laws, Bonnie V; Dickenson, Eric R V; Johnson, Theodore A; Snyder, Shane A; Drewes, Jörg E

    2011-02-15

    The attenuation of a diverse suite of contaminants of emerging concern (CECs) and bulk water quality changes was evaluated at a surface-spreading aquifer recharge operation across a detailed subsurface profile (9 locations), representing both short- and long-travel times (10 h to 60 days). Seventeen CECs were detected in the recharge basin and the concentrations of all were reduced during soil aquifer treatment (SAT), with 11 of the target compounds attenuated by >80% after 60 days of travel time. Select CECs (atenolol, gemfibrozil, N,N-diethly-3-methylbenzamide, meprobamate, tris(2-chloroethyl)phosphate, and primidone) and bulk water organic-carbon measurements (total organic carbon, biodegradable organic carbon, size-exclusion chromatography and fluorescence excitation-emission matrices) were identified as monitoring parameters that can be used to assess SAT performance at surface-spreading operations. PMID:21211820

  13. Bioavailability of residual polycyclic aromatic hydrocarbons following enhanced natural attenuation of creosote-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Juhasz, Albert L., E-mail: albert.juhasz@unisa.edu.a [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia); Smith, Euan [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia); Waller, Natasha [CSIRO Land and Water, Glen Osmond, SA 5064 (Australia); Stewart, Richard [Remediate, Kent Town, SA 5067 (Australia); Weber, John [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095 (Australia)

    2010-02-15

    The impact of residual PAHs (2250 +- 71 mug total PAHs g{sup -1}) following enhanced natural attenuation (ENA) of creosote-contaminated soil (7767 +- 1286 mug total PAHs g{sup -1}) was assessed using a variety of ecological assays. Microtox{sup TM} results for aqueous soil extracts indicated that there was no significant difference in EC{sub 50} values for uncontaminated, pre- and post-remediated soil. However, in studies conducted with Eisenia fetida, PAH bioaccumulation was reduced by up to 6.5-fold as a result of ENA. Similarly, Beta vulgaris L. biomass yields were increased 2.1-fold following ENA of creosote-contaminated soil. While earthworm and plant assays indicated that PAH bioavailability was reduced following ENA, the residual PAH fraction still exerted toxicological impacts on both receptors. Results from this study highlight that residual PAHs following ENA (presumably non-bioavailable to bioremediation) may still be bioavailable to important receptor organisms such as earthworms and plants. - Residual PAHs in creosote-contaminated soil following enhanced natural attenuation impacted negatively on ecological receptors.

  14. Bioavailability of residual polycyclic aromatic hydrocarbons following enhanced natural attenuation of creosote-contaminated soil

    International Nuclear Information System (INIS)

    The impact of residual PAHs (2250 ± 71 μg total PAHs g-1) following enhanced natural attenuation (ENA) of creosote-contaminated soil (7767 ± 1286 μg total PAHs g-1) was assessed using a variety of ecological assays. MicrotoxTM results for aqueous soil extracts indicated that there was no significant difference in EC50 values for uncontaminated, pre- and post-remediated soil. However, in studies conducted with Eisenia fetida, PAH bioaccumulation was reduced by up to 6.5-fold as a result of ENA. Similarly, Beta vulgaris L. biomass yields were increased 2.1-fold following ENA of creosote-contaminated soil. While earthworm and plant assays indicated that PAH bioavailability was reduced following ENA, the residual PAH fraction still exerted toxicological impacts on both receptors. Results from this study highlight that residual PAHs following ENA (presumably non-bioavailable to bioremediation) may still be bioavailable to important receptor organisms such as earthworms and plants. - Residual PAHs in creosote-contaminated soil following enhanced natural attenuation impacted negatively on ecological receptors.

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

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, Kenneth M.; Martin, Wayne J.

    2001-07-23

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

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

    International Nuclear Information System (INIS)

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

  17. Scattering contribution and higher order harmonic contamination in attenuation measurement in the x-ray regime for copper

    International Nuclear Information System (INIS)

    Full text: High-precision attenuation measurements can now lead to a direct assessment of scattering models in the X-ray regime. This is true not just at high energies but even when scattering cross-sections typically lie below 0.1% of the photoelectric absorption cross-section. This allows model-independent results to be obtained in these attenuation experiments for the first time. One of the major concerns in synchrotron studies is higher order harmonic contamination. Our technique of optimising and correcting for this effect will be discussed

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-08-04

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

  19. Effects of climatic modalities on polycyclic aromatic hydrocarbons (PAHs) availability and attenuation in historically contaminated Technosol

    Science.gov (United States)

    Dagois, Robin; Schwartz, Christophe; Faure, Pierre

    2014-05-01

    Since the decline of industrial activities in France, large areas of polycyclic aromatic hydrocarbon (PAHs)-contaminated soils have remained derelict. Thus, the fate of PAHs in such soils through natural attenuation process needs to be assessed. On the long-term scale (10-100 years), climate will greatly contribute to the evolution of soil physico-chemical properties and by consequences PAHs availability. In our study, we examined the effect of three contrasted climatic conditions (freeze-thawing, wetting-drying and high temperature) on soil aging processes of 11 historically contaminated soils and consequences on the availability of polycyclic aromatic compounds (including the 16 priority pollutants PAHs). Batch experiments were set-up for each modality; freeze-dried soil underwent variation of humidity and/or temperature. In a first step, PACs availability was roughly evaluated, with a water-extraction method using a H2O2 + CaCl2 solution. Dissolved organic carbon (DOC) content was measured in these extracts before and after applying the climatic modalities. Difference in DOC indicated an effect of the climatic modality on PACs availability. If an effect was noticed, available PACs was then accurately measured using (i) an hydrogen-peroxide oxidation on the soils followed (ii) a dichloromethane (DCM) extraction and a Gas Chromatography - Mass Spectrometer (GC-MS) quantification of the remaining PACs (i.e. unavailable). Variation of PACs availability will greatly help to understand the mechanisms associated between PACs desorption/sequestration and the abiotic influence of climate. Results of this work will further help understanding and predict the rate of natural attenuation of PACs in contaminated soils for the incoming decades.

  20. A Framework for Assessing the Sustainability of Monitored Natural Attenuation

    Science.gov (United States)

    Chapelle, Francis H.; Novak, John; Parker, John; Campbell, Bruce G.; Widdowson, Mark A.

    2007-01-01

    The sustainability of monitored natural attenuation (MNA) over time depends upon (1) the presence of chemical/biochemical processes that transform wastes to innocuous byproducts, and (2) the availability of energy to drive these processes to completion. The presence or absence of contaminant-transforming chemical/biochemical processes can be determined by observing contaminant mass loss over time and space (mass balance). The energy available to drive these processes to completion can be assessed by measuring the pool of metabolizable organic carbon available in a system, and by tracing the flow of this energy to available electron acceptors (energy balance). For the special case of chlorinated ethenes in ground-water systems, for which a variety of contaminant-transforming biochemical processes exist, natural attenuation is sustainable when the pool of bioavailable organic carbon is large relative to the carbon flux needed to drive biodegradation to completion. These principles are illustrated by assessing the sustainability of MNA at a chlorinated ethene-contaminated site in Kings Bay, Georgia. Approximately 1,000 kilograms of perchloroethene (PCE) was released to a municipal landfill in the 1978-1980 timeframe, and the resulting plume of chlorinated ethenes migrated toward a nearby housing development. A numerical model, built using the sequential electron acceptor model code (SEAM3D), was used to quantify mass and energy balance in this system. The model considered the dissolution of non-aqueous phase liquid (NAPL) as the source of the PCE, and was designed to trace energy flow from dissolved organic carbon to available electron acceptors in the sequence oxygen > chlorinated ethenes > ferric iron > sulfate > carbon dioxide. The model was constrained by (1) comparing simulated and measured rates of ground-water flow, (2) reproducing the observed distribution of electron-accepting processes in the aquifer, (3) comparing observed and measured concentrations of

  1. Natural attenuation of chlorinated-hydrocarbon contamination at Fort Wainwright, Alaska; a hydrogeochemical and microbiological investigation workplan

    Science.gov (United States)

    McCarthy, Kathleen A.; Lilly, Michael R.; Braddock, Joan F.; Hinzman, Larry D.

    1998-01-01

    Natural attenuation processes include biological degradation, by which microorganisms break down contaminants into simpler product compounds; adsorption of contaminants to soil particles, which decreases the mass of contaminants dissolved in ground water; and dispersion, which decreases dissolved contaminant concentrations through dilution. The primary objectives of this study are to (1) assess the degree to which such natural processes are attenuating chlorinated-hydrocarbon contamination in ground water, and (2) evaluate the effects of ground-water/surface-water interactions on natural-attenuation processes in the area of the former East and West Quartermasters Fueling Systems for Fort Wainwright, Alaska. The study will include investigations of the hydrologic, geochemical, and microbiological processes occurring at this site that influence the transport and fate of chlorinated hydrocarbons in ground water. To accomplish these objectives, a data-collection program has been initiated that includes measurements of water-table elevations and the stage of the Chena River; measurements of vertical temperature profiles within the subsurface; characterization of moisture distribution and movement in the unsaturated zone; collection of ground-water samples for determination of both organic and inorganic chemical constituents; and collection of ground-water samples for enumeration of microorganisms and determination of their potential to mineralize contaminants. We will use results from the data-collection program described above to refine our conceptual model of hydrology and contaminant attenuation at this site. Measurements of water-table elevations and river stage will help us to understand the magnitude and direction of ground-water flow and how changes in the stage of the Chena River affect ground-water flow. Because ambient ground water and surface water typically have different temperature characteristics, temperature monitoring will likely provide further insight

  2. Monitored Natural Attenuation of ino9rganic Contaminants Treatability Study Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Crapse, K

    2004-05-19

    The identification and quantification of key natural attenuation processes for inorganic contaminants at D-Area is detailed herein. Two overarching goals of this evaluation of monitored natural attenuation (MNA) as a remediation strategy were (1) to better define the availability of inorganic contaminants as potential sources for transport to groundwater and uptake by environmental receptors and (2) to understand the site-specific mechanisms controlling attenuation of these inorganic contaminants through tandem geochemical and biological characterization. Data collected in this study provides input for more appropriate site groundwater transport models. Significant natural attenuation is occurring at D-Area as evidenced by relatively low aqueous concentrations of constituents of concern (COCs) (Be, Ni, U, and As) at all locations characterized and the decrease in groundwater concentrations with increasing distance from the source. The observed magnitude of decrease in groundwater concentrations of COCs with distance from the D-Area Coal Pile Runoff Basin (DCPRB) could not be accounted for by the modeled physical attenuation processes of dilution/dispersion. This additional attenuation, i.e., the observed difference between the groundwater concentrations of COCs and the modeled physical attenuation, is due to biogeochemical processes occurring at the D-Area. In tandem geochemical and microbiological characterization studies designed to evaluate the mechanisms contributing to natural attenuation, pH was the single parameter found to be most predictive of contaminant attenuation. The increasing pH with distance from the source is likely responsible for increased sorption of COCs to soil surfaces within the aquifer at D-Area. Importantly, because the sediments appear to have a high buffering capacity, the acid emanating from the DCPRB has been neutralized by the soil, and these conditions have led to large Kd values at the site. Two major types of soils are present at

  3. Natural attenuation of arsenic in soils near a highly contaminated historical mine waste dump

    Czech Academy of Sciences Publication Activity Database

    Drahota, P.; Filippi, Michal; Ettler, V.; Rohovec, Jan; Mihaljevič, M.; Šebek, O.

    2012-01-01

    Roč. 414, January (2012), s. 546-555. ISSN 0048-9697 R&D Projects: GA AV ČR KJB300130702 Institutional research plan: CEZ:AV0Z30130516 Keywords : Arsenic * contaminated soil * historical mine waste dump * long-term attenuation Subject RIV: DD - Geochemistry Impact factor: 3.258, year: 2012

  4. Evaluating Ecosystem Services for Reducing Groundwater Nitrate Contamination: Nitrate Attenuation in the Unsaturated and Saturated Zones

    Science.gov (United States)

    Wang, J.

    2013-12-01

    Nitrates are the most common type of groundwater contamination in agricultural regions. Environmental policies targeting nitrates have focused on input control (e.g., restricted fertilizer application), intermediate loads control (e.g., reduce nitrate leached from crop fields), and final loads control (e.g., reduce catchment nitrate loads). Nitrate loads can be affected by hydrological processes in both unsaturated and saturated zones. Although many of these processes have been extensively investigated in literature, they are commonly modeled as exogenous to farm management. A couple of recent studies by scientists from the Lawrence Livermore National Laboratory show that in some situations nitrate attenuation processes in the unsaturated/saturated zone, particularly denitrification, can be intensified by certain management practices to mitigate nitrate loads. Therefore, these nitrate attenuation processes can be regarded as a set of ecosystem services that farmers can take advantage of to reduce their cost of complying with environmental policies. In this paper, a representative California dairy farm is used as a case study to show how such ecosystem attenuation services can be framed within the farm owner's decision-making framework as an option for reducing groundwater nitrate contamination. I develop an integrated dynamic model, where the farmer maximizes discounted net farm profit over multiple periods subject to environmental regulations. The model consists of three submodels: animal-waste-crop, hydrologic, and economic model. In addition to common choice variables such as irrigation, fertilization, and waste disposal options, the farmer can also endogenously choose from three water sources: surface water, deep groundwater (old groundwater in the deep aquifer that is not affected by farm effluent in the short term), and shallow groundwater (drainage water that can be recycled via capture wells at the downstream end of the farm). The capture wells not only

  5. Evaluating Transport and Attenuation of Inorganic Contaminants in the Vadose Zone for Aqueous Waste Disposal Sites

    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); Tartakovsky, Guzel D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-09-01

    An approach was developed for evaluating vadose zone transport and attenuation of aqueous wastes containing inorganic (non-volatile) contaminants that were disposed of at the land surface (i.e., directly to the ground in cribs, trenches, tile fields, etc.) and their effect on the underlying groundwater. The approach provides a structured method for estimating transport of contaminants through the vadose zone and the resulting temporal profile of groundwater contaminant concentrations. The intent of the approach is also to provide a means for presenting and explaining the results of the transport analysis in the context of the site-specific waste disposal conditions and site properties, including heterogeneities and other complexities. The document includes considerations related to identifying appropriate monitoring to verify the estimated contaminant transport and associated predictions of groundwater contaminant concentrations. While primarily intended for evaluating contaminant transport under natural attenuation conditions, the approach can also be applied to identify types of, and targets for, mitigation approaches in the vadose zone that would reduce the temporal profile of contaminant concentrations in groundwater, if needed.

  6. Calculational Tool for Skin Contamination Dose Assessment

    CERN Document Server

    Hill, R L

    2002-01-01

    Spreadsheet calculational tool was developed to automate the calculations preformed for dose assessment of skin contamination. This document reports on the design and testing of the spreadsheet calculational tool.

  7. Groundwater contamination and natural attenuation capacity at a petroleum spilled facility in Korea

    Institute of Scientific and Technical Information of China (English)

    Hyun-Mi Choi; Jin-Yong Lee

    2011-01-01

    As a remedial option,the natural attenuation capacity of a petroleum contaminated groundwater at a military facility was examined.Hydrogeological conditions,such as high water level,permeable uppermost layer and frequent heavy rainfall,were favorable to natural attenuation at this site.The changes in the concentrations of electron acceptors and donors,as well as the relevant hydrochemical conditions,indicated the occurrence of aerobic respiration,denitrification,iron reduction,manganese reduction and sulfate reduction.The calculated BTEX expressed biodegradation capacity ranged between 20.52 and 33.67 mg/L,which appeared effective for the reduction of the contaminants levels.The contribution of each electron accepting process to the total biodegradation was in the order:denitrification > iron reduction > sulfate reduction > aerobic respiration > manganese reduction.The BTEX and benzene point attenuation rates were 0.0058-0.0064 and 0.0005-0.0032 day-1,respectively,and the remediation time was 0.7-1.2 and 2.5-30 years,respectively.The BTEX and benzene bulk attenuation rates were 8.69 × 10-4 and 1.05 × 10-3 day-1,respectively,and the remediation times for BTEX and benzene were 7.2 and 17.5 years,respectively.However,most of the natural attenuation occurring in this site can be attributed to dilution and dispersion.Consequently,the biodegradation and natural attenuation capacities were good enough to lower the contaminants levels,but their rates appeared to be insufficient to reach the remediation goal within a reasonable time frame.Therefore,some active remedial measures would be required.

  8. Pulsed gas injection: A minimum effort approach for enhanced natural attenuation of chlorobenzene in contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Balcke, Gerd Ulrich, E-mail: gerd.balcke@metanomics.d [Department of Hydrogeology, UFZ Helmholtz Centre for Environmental Research, Theodor-Lieser-Strasse 4, D-06120 Halle/Saale (Germany); Paschke, Heidrun [Department of Groundwater Remediation, UFZ Helmholtz Centre for Environmental Research, Permoserstrasse 15, D-04318 Leipzig (Germany); Vogt, Carsten [Department of Isotope Biogeochemistry, UFZ Helmholtz Centre for Environmental Research, Permoserstrasse 15, D-04318 Leipzig (Germany); Schirmer, Mario [EAWAG, Swiss Federal Institute of Aquatic Science and Technology, Department of Water Resources and Drinking Water, Ueberlandstrasse 133, 8600 Duebendorf (Switzerland)

    2009-07-15

    Chlorobenzene-contaminated groundwater was used to assess pulsed gas sparging as a minimum effort aeration strategy to enhance intrinsic natural attenuation. In contrast to existing biosparging operations, oxygen was supplied at minimum rate by reducing the gas injection frequency to 0.33 day{sup -1}. Field tests in a model aquifer were conducted in a 12 m long reactor, filled with indigenous aquifer material and continuously recharged with polluted groundwater over 3 years. The closed arrangement allowed yield balances, cost accounting as well as the investigation of spatial distributions of parameters which are sensitive to the biodegradation process. Depending on the injection frequency and on the gas chosen for injection (pure oxygen or air) oxygen-deficient conditions prevailed in the aquifer. Despite the limiting availability of dissolved oxygen in the groundwater, chlorobenzene degradation under oxygen-deficient conditions proved to be more effective than under conditions with dissolved oxygen being available in high concentrations. - Minimum rate gas sparging resulted in sustained biodegradation of chlorobenzene in a polluted groundwater aquifer.

  9. Pulsed gas injection: A minimum effort approach for enhanced natural attenuation of chlorobenzene in contaminated groundwater

    International Nuclear Information System (INIS)

    Chlorobenzene-contaminated groundwater was used to assess pulsed gas sparging as a minimum effort aeration strategy to enhance intrinsic natural attenuation. In contrast to existing biosparging operations, oxygen was supplied at minimum rate by reducing the gas injection frequency to 0.33 day-1. Field tests in a model aquifer were conducted in a 12 m long reactor, filled with indigenous aquifer material and continuously recharged with polluted groundwater over 3 years. The closed arrangement allowed yield balances, cost accounting as well as the investigation of spatial distributions of parameters which are sensitive to the biodegradation process. Depending on the injection frequency and on the gas chosen for injection (pure oxygen or air) oxygen-deficient conditions prevailed in the aquifer. Despite the limiting availability of dissolved oxygen in the groundwater, chlorobenzene degradation under oxygen-deficient conditions proved to be more effective than under conditions with dissolved oxygen being available in high concentrations. - Minimum rate gas sparging resulted in sustained biodegradation of chlorobenzene in a polluted groundwater aquifer.

  10. Comparison of reactive transport model predictions for natural attenuation processes occurring at chlorinated solvent contaminated site

    Science.gov (United States)

    Chiu, H. M.; Tsai, C. H.; Lai, K. H.; Chen, J. S.

    2014-12-01

    Prediction of an analytical model and numerical model, namely BIOCLOR and HYDRODEOCHEM, for a test scenario involving the natural attenuations of dissolved solvent at chlorinated contaminated site are compared. Two models make same predictions for PCE, TCE and DCE and considerable different predictions for VC and ETH for the case of all species having identical retardation factors. Significant discrepancies between two models are observed for all species when retardation coefficients are considered to be different for all species. These differences can be attributed to the basic assumption that all the species have the same retardation factors embedded in BIOCHLOR.

  11. Risk assessment of mercury contaminated sites

    International Nuclear Information System (INIS)

    At two sites, highly contaminated with mercury, risk assessment was executed. Methods were developed to determine organomercury compounds in water, air and soil. Toxicity tests demonstrated the high toxicity of organomercury compounds compared to inorganic mercury. Besides highly toxic methylmercury, ethylmercury was found in soils close to a chemical plant in Marktredwitz. In ultrafiltration-experiments mercury showed great affinity to high molecular substances in water. Lysimeter-experiments proved, that organomercury compounds are adsorbed and transformed to inorganic and elemental mercury. (orig.)

  12. Monitored Natural Attenuation of Inorganic Contaminants in Ground Water Volume 3 Assessment for Radionuclides IncludingTritium, Radon, Strontium, Technetium, Uranium, Iodine, Radium, Thorium, Cesium, and Plutonium-Americium

    Science.gov (United States)

    The current document represents the third volume of a set of three volumes that address the technical basis and requirements for assessing the potential applicability of MNA as part of a ground-water remedy for plumes with nonradionuclide and/or radionuclide inorganic contamina...

  13. The Relationship Between Partial Contaminant Source Zone Remediation and Groundwater Plume Attenuation

    Science.gov (United States)

    Falta, R. W.

    2004-05-01

    .R. Gonzales, P. Haas, T.P. Clement, and Y. Sun, 2000, BIOCHLOR Natural Attenuation Decision Support System User's Manual Version 1.0, US EPA Report EPA/600/R-00/008 Domenico, P.A., 1987, An analytical model for multidimensional transport of a decaying contaminant species, J. Hydrol., 91: 49-58. Sun, Y., J.N. Petersen, T.P. Clement, and R.S. Skeen, 1999, A new analytical solution for multi-species transport equations with serial and parallel reactions, Water Resour. Res., 35(1): 185-190.

  14. Benzene-contaminated groundwaters-transport parameters and isotopic evidence for natural attenuation

    International Nuclear Information System (INIS)

    increasing apparent ages in flow direction might be evident. The upper aquifer is phreatic, and therefore 3He contents there may be affected by diffusive losses. However, tritium contents in both aquifers indicate apparent ages of less than 15 years. The confinement of the deeper aquifer probably preserves most of tritiugenic 3He. Apparent groundwater ages in Figure 1 indicate a recharge in 1975 or younger. Thus, it is probable that at least in the deeper aquifer the contaminant plume does not 'flow' together with the groundwater. The energy consumption of natural attenuation processes may be covered by 'oxidizers' like nitrate and/or sulphate. Because in contaminated as well as non-contaminated groundwaters of the investigation area the nitrate level is very low, attention was focussed on the isotopic composition of sulphate (δ34S) as possible source of energy and on dissolved inorganic carbon (DIC; δ13C) as indicator of totally decomposed hydrocarbons. Fig. 2 shows sulphate content and its δ34S along a flow path in aquifer I, reflecting isotopic enrichment in sulphate due to bacterial reduction. This trend corresponds to a slight decrease of δ13C of DIC from -22.4 per mille to -23.7 per mille confirming the hypothesis of bacterial decomposition of hydrocarbons as natural attenuation process

  15. Equilibrium sampling for a thermodynamic assessment of contaminated sediments

    DEFF Research Database (Denmark)

    Mayer, Philipp; Nørgaard Schmidt, Stine; Mäenpää, Kimmo;

    Hydrophobic organic contaminants (HOCs) reaching the aquatic environment are largely stored in sediments. The risk of contaminated sediments is challenging to assess since traditional exhaustive extraction methods yield total HOC concentrations, whereas freely dissolved concentrations (Cfree...

  16. Recurrent and sporadic Listeria monocytogenes contamination in alheiras represents considerable diversity, including virulence-attenuated isolates.

    Science.gov (United States)

    Felício, M T S; Hogg, T; Gibbs, P; Teixeira, P; Wiedmann, M

    2007-06-01

    Microbiological characterization of alheiras, traditional smoked meat sausages produced in northern Portugal, had previously shown that more than 60% of the lots analyzed were contaminated with Listeria monocytogenes at levels higher than 100 CFU/g. In order to better understand L. monocytogenes contamination patterns in alheiras, we characterized 128 L. monocytogenes isolates from alheiras using a variety of subtyping techniques (i.e., molecular serotyping; arsenic, cadmium, and tetracycline resistance typing; and pulsed-field gel electrophoresis [PFGE]). Subtyping of isolates from products collected on two separate dates provided evidence for the persistence of specific L. monocytogenes PFGE types in the production and distribution chains of alheiras from four different processors. A subset of 21 isolates was further characterized using ribotyping and Caco-2 cell invasion assays to evaluate the pathogenic potential of L. monocytogenes present in alheiras. Caco-2 invasion assays revealed seven isolates with invasion efficiencies that were less than 20% of that of the control strain 10403S. All seven isolates had premature stop codons in inlA that represented three distinct mutations, which had previously been observed in isolates from the United States or France. Our findings indicate the need for a comprehensive approach to control L. monocytogenes in alheiras, including strategies to reduce persistence. The presence of considerable diversity in invasion phenotypes among L. monocytogenes strains present in alheiras, including the presence of subtypes likely to be virulence attenuated, may provide an opportunity to initially focus control strategies on the subtypes most likely to cause human disease. PMID:17449681

  17. Assisted attenuation of a soil contaminated by diuron using hydroxypropyl-β-cyclodextrin and organic amendments.

    Science.gov (United States)

    Rubio-Bellido, Marina; Madrid, Fernando; Morillo, Esmeralda; Villaverde, Jaime

    2015-01-01

    Diuron desorption and mineralisation were studied on an amended and artificially contaminated soil. The amendments used comprised two different composted organic residues i.e., sewage sludge (SS) mixed with pruning wastes, and urban solid residues (USR), and two different solutions (with inorganic salts as the micronutrients and hydroxypropyl-β-cyclodextrin (HPBCD)). After applying micronutrients to activate the soil flora, 15.5% mineralisation could be reached after 150 days, indicating that the soil has a potential capacity to mineralise the herbicide through biostimulation-assisted attenuation. Diuron mineralisation was also improved when HPBCD solutions were applied. Indeed, the extent of herbicide mineralisation reached 29.7% with this application. Moreover, both the lag phase and the half-life time (DT50) were reduced to 33 and 1,778 days, respectively, relative to the application of just micronutrients (i.e., 39 and 6297 days, respectively). Organic amendments were also applied (i.e., USR and SS) on the contaminated soil: it was found that the diuron mineralisation rate was improved as the amendment concentration increased. The joint application of all treatments investigated at the best conditions tested was conducted to obtain the best diuron mineralisation results. The micronutrient amendment plus 4% USR or SS amendment plus HPBCD solution (10-fold diuron initially spiked) caused an extent of diuron mineralisation 33.2 or 46.5%, respectively. PMID:25310830

  18. Feasibility of using natural attenuation as a remedial alternative for explosives-contaminated groundwater at Site L1, Joliet Army Ammunition Plant, Joliet, Illinois. Final report for August 1998

    Energy Technology Data Exchange (ETDEWEB)

    Pennington, J.C.; Harrelson, D.W.; Zakikhani, M.; Gunnison, D.; Clarke, J.U.

    1998-08-01

    Natural attenuation may be an attractive alternative to more expensive remediation technologies at sites that meet well-defined selection criteria, acceptable risk levels, and that satisfy specific regulatory concerns. Environmental remediation technology is necessarily evolving toward less expensive, less intrusive, long-term solutions. Natural attenuation may be a legitimate and sensible alternative to other remediation methods if appropriate evidence of protection for potential contaminant receptors is documented. A recent study by the US Army Engineer Waterways Experiment Station (WES) verified a regulatory attitude of potential acceptance of natural attenuation for explosives-contaminated sites. This study confirmed that most regulatory agencies would accept natural attenuation given appropriate scientific, engineering, and risk assessment data.

  19. Natural attenuation of organic contaminants at the interface between groundwater and surface water

    Energy Technology Data Exchange (ETDEWEB)

    Middeldorp, P.; Staps, S.; Rijnaarts, H. [TNO-MEP Environment, Energy and Process Innovation, Apeldoorn (Netherlands); Roelofsen, F.; Valstar, J. [TNO-NITG, Apeldoorn (Netherlands); Smits, J. [WL/Delf Hydraulics (Netherlands)

    2003-07-01

    There are strong indications that the interface between groundwater and surface water plays an important role in the natural degradation of organic contaminants (NA-interface). This is especially the case for mobile contaminants that are relatively persistent in an anaerobic (subsurface) environment, and are mineralised relatively easy under more oxidized environmental conditions (e.g. benzene, chlorobenzene, vinyl chloride, the light aliphatic fraction of mineral oil, etc.). These compounds are often also present as degradation products of natural or stimulated in situ biodegradation processes. Previous investigations have indicated indirectly that NA-interface processes contribute to a reduction of contaminant flux into surface water systems. Until now, no straightforward assessment and quantification of NA-interface has been performed. Moreover, limit values for allowable influx of contamination from a site into a surface water system do not exist. This prevents a possible beneficial use of NA-interface processes as a part of a cost-effective and integrated soil and water quality management. This project aims to gain more understanding of the occurrence of NA-interface processes, to quantify their contribution to emission reduction towards the surface water system and, in case of substantial contribution, to promote application of NA-interface as a part of a cost-effective integrated environmental management of contaminated sites and surrounding water bodies. The project's starting point is that the surface water is regarded as an object of risk and not as a reactor. Thus, effective degradation in the interface does not move environmental problems to surface water systems, but eliminates contaminants by natural occurring processes, thus protecting the aquatic ecosystem. (orig.)

  20. Assessment of nitrate contamination risk: The Italian experience

    OpenAIRE

    Capri, E.; Delgado Huertas, Antonio; VASSALLO, M

    2009-01-01

    The purpose of this study is to show the results of the Italian research project of national interest (PRIN) launched in 2006 and finished in 2008, concerning the “assessment of groundwater contamination risk by nitrates assessment”. The project verified the IPNOA method for nitrate groundwater contamination risk assessment in four test-sites of Italy. The IPNOA is a parametric index which assesses the potential hazard of nitrate contamination originating from agriculture on a regional scale....

  1. Comparison of monitored natural attenuation with other alternatives for remediation of contaminated groundwater at Naval Air Station (NAS) Fallon, USA

    International Nuclear Information System (INIS)

    Monitored natural attenuation (MNA) and several other potential alternatives were evaluated for remediation of dissolved-phase groundwater contamination at Site 1, the former crash crew training area at NAS Fallon. The contaminants of concern at the site are petroleum hydrocarbon constituents and chlorinated ethenes. Remedial action objectives were developed using a conceptual model for the site, applicable regulatory action levels, site contaminants, and a point-of-compliance. A field evaluation of MNA was conducted at Site 1. Monitored natural attenuation was compared to other potential remedial alternatives for achieving the RAOs including: plume containment using pumping wells, interceptor drain, or slurry wall; and active restoration with enhanced in situ bioremediation, pump and treat using wells, or pump and treat using an interceptor drain. Alternatives were comparatively evaluated using three criteria, effectiveness, ability to implement and cost. The evaluation indicates that MNA is a viable and cost-effective remedial alternative for Site 1

  2. Salt contamination assessment and remediation guidelines

    International Nuclear Information System (INIS)

    Environmental impacts associated with excess salt in oil and surface water or groundwater (a frequent occurrence in oil and gas production) may be manifested as degradation of soil chemical or physical properties, impaired vegetable growth and degraded surface or groundwater quality. Spill prevention is by far the most effective and most efficient way of avoiding these adverse effects and the attendant remediation costs. However, when spills do occur effective response, based on a comprehensive understanding of impacts, salt movements and remediation procedures can mitigate the adverse environmental effects. This guide is designed to assist those involved in the prevention, assessment, remediation and management of salt-contaminated sites. It summarizes the regulatory requirements in Alberta, including salt remediation objectives, and provides an overview of salt spill problems and effective site assessment and remediation procedures. Background information on the sources of salt, the movement of salt in soil and groundwater, and the adverse effects of salt on soil, vegetation and groundwater is provided in an appendix attached to the Guide. A selected bibliography and a glossary of terms are also included. 42 refs., tabs., figs

  3. Contamination assessment for OSSA space station IOC payloads

    Science.gov (United States)

    Chinn, S.; Gordon, T.; Rantanen, R.

    1987-01-01

    The results are presented from a study for the Space Station Planners Group of the Office of Space Sciences and Applications. The objectives of the study are: (1) the development of contamination protection requirements for protection of Space Station attached payloads, serviced payloads and platforms; and (2) the determination of unknowns or major impacts requiring further assessment. The nature, sources, and quantitative properties of the external contaminants to be encountered on the Station are summarized. The OSSA payload contamination protection requirements provided by the payload program managers are reviewed and the level of contamination awareness among them is discussed. Preparation of revisions to the contamination protection requirements are detailed. The comparative impact of flying the Station at constant atmospheric density rather than constant altitude is assessed. The impact of the transverse boom configuration of the Station on contamination is also assessed. The contamination protection guidelines which OSSA should enforce during their development of payloads are summarized.

  4. Metal speciation and attenuation in stream waters and sediments contaminated by landfill leachate

    Science.gov (United States)

    Ettler, Vojtěch; Matura, Marek; Mihaljevič, Martin; Bezdička, Petr

    2006-02-01

    The degree of metal contamination (Zn, Pb, Cu, Ni, Cd) has been investigated in the vicinity of an old unmonitored municipal landfill in Prague, Czech Republic, where the leachate is directly drained into a surface stream. The water chemistry was coupled with investigation of the stream sediment ( aqua regia extract, sequential extraction, voltammetry of microparticles) and newly formed products (SEM/EDS, XRD). The MINTEQA2 speciation-solubility calculation showed that the metals (Zn, Pb, Cu, Ni) are mainly present as carbonate complexes in leachate-polluted surface waters. These waters were oversaturated with respect to Fe(III) oxyhydroxides, calcite (CaCO3) and other carbonate phases. Three metal attenuation mechanisms were identified in leachate-polluted surface waters: (i) spontaneous precipitation of metal-bearing calcite exhibiting significant concentrations of trace elements (Fe, Mn, Mg, Sr, Ba, Pb, Zn, Ni); (ii) binding to Fe(III) oxyhydroxides (mainly goethite, FeOOH) (Pb, Zn, Cu, Ni); and (iii) preferential bonding to sediment organic matter (Cu). These processes act as the key scavenging mechanisms and significantly decrease the metal concentrations in leachate-polluted water within 200 m from the direct leachate outflow into the stream. Under the near-neutral conditions governing the sediment/water interface in the landfill environment, metals are strongly bound in the stream sediment and remain relatively immobile.

  5. Oak Ridge Integrated Field-Scale Research Challenge ERKP686: Multi-scale Investigations on the Rates and Mechanisms of Targeted Immobilization and Natural Attenuation of Metal, Radionuclide and Co-Contaminants in the Subsurface (project overview)

    International Nuclear Information System (INIS)

    Historical disposal of wastes from the operation of three industrial plant sites on the Oak Ridge Reservation (ORR) has created extensive areas of subsurface inorganic, organic, and radioactive contamination (thousands of unlined trenches, pits, ponds). These wastes have resulted in approximately 1,500 acres of contaminated groundwater on the ORR. Much of the original contamination is now present as secondary sources within the soil-rock matrix outside of the original disposal sites. The secondary source areas are extensive and encompass regions on the watershed scale (tens of km). A significant limitation in assessing remediation needs of the secondary contaminant sources is the lack of information on the rates and mechanisms of coupled hydrological, geochemical, and microbial processes that control contaminant migration. Contaminant fluxes emanating from the secondary sources are often so high as to prevent complete attenuation of the groundwater plumes. Interventions such as source actions may be a prerequisite for effective and rapid natural attenuation (source actions such as: reduction of the soluble contaminant concentration at the source or controlling the flux from the source to groundwater by decreasing recharge). The goals are to advance the understanding and predictive capability of coupled hydrological, geochemical, and microbiological processes that control in situ transport, remediation and natural attenuation of metals, radionuclides, and co-contaminants (i.e. U, Tc, NO3) across multiple scales ranging from molecular to watershed levels. Provide multi-process, multi-scale predictive monitoring and modeling tools that can be used at sites throughout the DOE complex to: (1) inform and improve the technical basis for decision making, and (2) assess which sites are amenable to natural attenuation and which would benefit from source zone remedial intervention. The objectives are: (1) quantify recharge and other hydraulic drivers for groundwater flow and

  6. Attenuation of contaminant plumes in homogeneous aquifers: Sensitivity to source function at moderate to large peclet numbers

    International Nuclear Information System (INIS)

    A groundwater mass transfer calculation is an essential part of the performance assessment for radioactive waste disposal facilities. AECL's IRUS (Intrusion Resistant Underground Structure) facility, which is designed for the near-surface disposal of low-level radioactive waste (LLRW), is to be situated in the sandy overburden at AECL's Chalk River Laboratories. Flow in the sandy aquifers at the proposed IRUS site is relatively homogeneous and advection-dominated (large Peclet numbers). Mass transfer along the mean direction of flow from the IRUS site may be described using the one-dimensional advection-dispersion equation, for which a Green's function representation of downstream radionuclide flux is convenient. This report shows that in advection-dominated aquifers, dispersive attenuation of initial contaminant releases depends principally on two time scales: the source duration and the pulse breakthrough time. Numerical investigation shows further that the maximum downstream flux or concentration depends on these time scales in a simple characteristic way that is minimally sensitive to the shape of the initial source pulse. (author). 11 refs., 2 tabs., 3 figs

  7. Assessment of Microbial Process Potential for Natural Attenuation of Contaminants in the Thick Vadose Zone beneath the Wastewater-irrigated Area of Southern Shijiazhuang City, Hebei Province%河北省石家庄市南部污灌区厚层包气带污染物自然衰减的微生物作用潜力评价

    Institute of Scientific and Technical Information of China (English)

    张翠云; 张胜; 何泽; 殷密英; 宁卓

    2014-01-01

    本次研究的目的是利用传统的培养技术和现代的磷脂脂肪酸 PLFA(Phosphor Lipid Fatty Acid)技术、Biolog技术、16 S rRNA基因变性梯度凝胶电泳DGGE(Denaturing Gradient Gel Electrophoresis)及测序技术,调查石家庄市南部污灌区厚近30 m包气带微生物含量、分布、活性和多样性,评价污灌区厚层包气带污染物自然衰减的微生物作用潜力。包气带沉积物样品通过岩芯钻探获得,用于物理、化学和微生物分析。结果显示,土壤层(5~20 cm)微生物含量高,活性高,代谢类型多,可培养的异养菌与自养菌、好氧异养菌、兼性厌氧异氧菌和专性厌氧异养菌共存;土壤层下伏包气带微生物含量较低,活性降低,代谢类型减少,可培养的细菌主要是好氧性异养菌、兼性厌氧异养菌和好氧自养菌,而且随岩性而变化,在砂层和重粘土层含量低,活性低,而在亚粘土层含量和活性大。研究结果指示土壤层具有很高的污染物生物自然衰减潜力,而且下伏包气带仍有这种潜力,特别是下部溶解有机碳 DOC(Dissolved Organic Carbon)含量高的层位潜力更大。%The purpose of this study is to investigate the abundance, distribution, activity and diversity of microbes in nearly 30 m thick vadose zone beneath the wastewater-irrigated area of southern Shijiazhuang to assess microbial process potential for natural attenuation of contaminants of the thick vadose zone using traditional cultivation technique and modern phosphor lipid fatty acid (PLFA), Biolog and 16 S rRNA gene denaturing gradient gel electrophoresis (DGGE) techniques. Sediment samples were collected by core drilling for analysis of physical, chemical and microbial properties. The results show that the top soil layer (5~20 cm) is characterized by high content of bacteria, high activity, plenty of metabolizable types and coexistence of culturable heterotrophic bacteria and autotrophic

  8. Quinoline and derivatives at a tar oil contaminated site: hydroxylated products as indicator for natural attenuation?

    Energy Technology Data Exchange (ETDEWEB)

    Anne-Kirsten Reineke; Thomas Goeen; Alfred Preiss; Juliane Hollender [RWTH Aachen, Aachen (Germany). Institute of Hygiene and Environmental Medicine

    2007-08-01

    LC-MS-MS analysis of groundwater of a tar oil contaminated site (a former coal mine and coking plant in Castrop-Rauxel, Germany) showed the occurrence of the N-heterocycles quinoline and isoquinoline as well as their hydroxylated and hydrogenated metabolites. The concentrations of the hydroxylated compounds, 2(1H)-quinolinone and 1(2H)-isoquinolinone, were significantly higher than those of the nonsubstituted parent compounds. Therefore, exclusive quantification of the parent compounds leads to an underestimation of the amount of N-heterocycles present in the groundwater. Microbial degradation experiments of quinoline and isoquinoline with aquifer material of the site as inocculum showed the formation of hydroxylated and hydrogenated products under sulfate-reducing conditions, the prevailing conditions in the field. However, since analyses of seven tar products showed that these compounds are also primary constituents, their detection in groundwater is found to be a nonsufficient indicator for the occurrence of biological natural attenuation processes. Instead, the ratio of hydroxylated to parent compound (R{sub metabolite}) is proposed as a useful indicator. We found that 65-83% of all groundwater samples showed R{sub metabolite} for 2(1H)-quinolinone, 1(2H)-isoquinolinone, 3,4-dihydro-2(1H)-quinolinone, and 3,4-dihydro-1(2H)-isoquinolinone, which was higher than the highest ratio found in tar products. With respect to the observed partition coefficient between tar oil and water of 3.5 for quinoline and isoquinoline and 0.3 for 2(1H)-quinolinone and 1(2H)-isoquinolinone, the ratio in groundwater would be approximately 10 times higher than the ratio in tar oil. When paying attention to these two parameters, 19-31% of groundwater samples exceed the highest tar oil ratio. This indicates that biological processes take place in the aquifer of the site and R{sub metabolite} is an applicable indicator for natural attenuation. 42 refs., 6 figs., 2 tabs.

  9. Radiological Risk Assessment and Survey of Radioactive Contamination for Foodstuffs

    Energy Technology Data Exchange (ETDEWEB)

    Lee, W.R.; Lee, C.W.; Choi, K.S.; and others

    2007-11-15

    After the Chernobyl nuclear accident in 1986, a radiological dose assessment and a survey of a radioactive contamination for foodstuffs have been investigated by many countries such as EU, Japan, USA. In the case of Japan which is similar to our country for the imported regions of foodstuffs, there were some instances of the excess for regulation on the maximum permitted levels of radioactive contamination among some imported foodstuffs. Concerns about the radioactive contamination of foodstuffs are increased because of the recently special situation (Nuclear test of North Korea). The purpose of this study is a radiological dose assessment and a survey of a radioactive contamination for foodstuffs in order to reduce the probability of intake of contaminated foodstuffs. Analytical results of the collected samples are below MDA. In this project, the model of radiological dose assessment via the food chain was also developed and radiological dose assessment was conducted based on surveys results of a radioactive contamination for foodstuffs in the Korean open markets since 2002. The results of radiological dose assessment are far below international reference level. It shows that public radiation exposure via food chain is well controlled within the international guide level. However, the radioactive contamination research of imported foodstuffs should be continuous considering the special situation(nuclear test of North Korea). These results are used to manage the radioactive contamination of the imported foodstuffs and also amend the regulation on the maximum permitted levels of radioactive contamination of foodstuffs.

  10. Radiological Risk Assessment and Survey of Radioactive Contamination for Foodstuffs

    International Nuclear Information System (INIS)

    After the Chernobyl nuclear accident in 1986, a radiological dose assessment and a survey of a radioactive contamination for foodstuffs have been investigated by many countries such as EU, Japan, USA. In the case of Japan which is similar to our country for the imported regions of foodstuffs, there were some instances of the excess for regulation on the maximum permitted levels of radioactive contamination among some imported foodstuffs. Concerns about the radioactive contamination of foodstuffs are increased because of the recently special situation (Nuclear test of North Korea). The purpose of this study is a radiological dose assessment and a survey of a radioactive contamination for foodstuffs in order to reduce the probability of intake of contaminated foodstuffs. Analytical results of the collected samples are below MDA. In this project, the model of radiological dose assessment via the food chain was also developed and radiological dose assessment was conducted based on surveys results of a radioactive contamination for foodstuffs in the Korean open markets since 2002. The results of radiological dose assessment are far below international reference level. It shows that public radiation exposure via food chain is well controlled within the international guide level. However, the radioactive contamination research of imported foodstuffs should be continuous considering the special situation(nuclear test of North Korea). These results are used to manage the radioactive contamination of the imported foodstuffs and also amend the regulation on the maximum permitted levels of radioactive contamination of foodstuffs

  11. A risk assessment tool for contaminated sites in low-permeability fractured media

    DEFF Research Database (Denmark)

    Chambon, Julie Claire Claudia; Binning, Philip John; Jørgensen, Peter R.;

    2011-01-01

    A risk assessment tool for contaminated sites in low-permeability fractured media is developed, based on simple transient and steady-state analytical solutions. The discrete fracture (DF) tool, which explicitly accounts for the transport along fractures, covers different source geometries and......, chlorinated solvents, benzene and MTBE. The model is compared with field data and with results from a simpler approach based on an Equivalent Porous Media (EPM). Risk assessment conclusions of the DF and EPM approaches are very different due to the early breakthrough, long term tailing, and lower attenuation...

  12. Groundwater contamination in coastal urban areas: Anthropogenic pressure and natural attenuation processes. Example of Recife (PE State, NE Brazil)

    Science.gov (United States)

    Bertrand, G.; Hirata, R.; Pauwels, H.; Cary, L.; Petelet-Giraud, E.; Chatton, E.; Aquilina, L.; Labasque, T.; Martins, V.; Montenegro, S.; Batista, J.; Aurouet, A.; Santos, J.; Bertolo, R.; Picot, G.; Franzen, M.; Hochreutener, R.; Braibant, G.

    2016-09-01

    In a context of increasing land use pressure (over-exploitation, surface-water contamination) and repeated droughts, identifying the processes affecting groundwater quality in coastal megacities of the tropical and arid countries will condition their long-term social and environmental sustainability. The present study focuses on the Brazilian Recife Metropolitan Region (RMR), which is a highly urbanized area (3,743,854 inhabitants in 2010) on the Atlantic coast located next to an estuarial zone and overlying a multi-layered sedimentary system featured by a variable sediment texture and organic content. It investigates the contamination and redox status patterns conditioning potential attenuation within the shallow aquifers that constitute the interface between the city and the strategic deeper semi-confined aquifers. These latter are increasingly exploited, leading to high drawdown in potenciometric levels of 20-30 m and up to 70 m in some high well density places, and potentially connected to the surface through leakage. From a multi-tracer approach (major ions, major gases, δ11B, δ18O-SO4, δ34S-SO4) carried out during two field campaigns in September 2012 and March 2013 (sampling of 19 wells and 3 surface waters), it has been possible to assess the contamination sources and the redox processes. The increasing trend for mineralization from inland to coastal and estuarial wells (from 119 to around 10,000 μS/cm) is at first attributed to water-rock interactions combined with natural and human-induced potentiometric gradients. Secondly, along with this trend, one finds an environmental pressure gradient related to sewage and/or surface-channel network impacts (typically depleted δ11B within the range of 10-15‰) that are purveyors of chloride, nitrate, ammonium and sulfate. Nitrate, ammonium and sulfate (ranging from 0 to 1.70 mmol/L, from 0 to 0,65 mmol/L, from 0.03 to 3.91 mmol/L respectively are also potentially produced or consumed through various redox

  13. Groundwater contamination in coastal urban areas: Anthropogenic pressure and natural attenuation processes. Example of Recife (PE State, NE Brazil).

    Science.gov (United States)

    Bertrand, G; Hirata, R; Pauwels, H; Cary, L; Petelet-Giraud, E; Chatton, E; Aquilina, L; Labasque, T; Martins, V; Montenegro, S; Batista, J; Aurouet, A; Santos, J; Bertolo, R; Picot, G; Franzen, M; Hochreutener, R; Braibant, G

    2016-09-01

    In a context of increasing land use pressure (over-exploitation, surface-water contamination) and repeated droughts, identifying the processes affecting groundwater quality in coastal megacities of the tropical and arid countries will condition their long-term social and environmental sustainability. The present study focuses on the Brazilian Recife Metropolitan Region (RMR), which is a highly urbanized area (3,743,854 inhabitants in 2010) on the Atlantic coast located next to an estuarial zone and overlying a multi-layered sedimentary system featured by a variable sediment texture and organic content. It investigates the contamination and redox status patterns conditioning potential attenuation within the shallow aquifers that constitute the interface between the city and the strategic deeper semi-confined aquifers. These latter are increasingly exploited, leading to high drawdown in potenciometric levels of 20-30m and up to 70m in some high well density places, and potentially connected to the surface through leakage. From a multi-tracer approach (major ions, major gases, δ(11)B, δ(18)O-SO4, δ(34)S-SO4) carried out during two field campaigns in September 2012 and March 2013 (sampling of 19 wells and 3 surface waters), it has been possible to assess the contamination sources and the redox processes. The increasing trend for mineralization from inland to coastal and estuarial wells (from 119 to around 10,000μS/cm) is at first attributed to water-rock interactions combined with natural and human-induced potentiometric gradients. Secondly, along with this trend, one finds an environmental pressure gradient related to sewage and/or surface-channel network impacts (typically depleted δ(11)B within the range of 10-15‰) that are purveyors of chloride, nitrate, ammonium and sulfate. Nitrate, ammonium and sulfate (ranging from 0 to 1.70mmol/L, from 0 to 0,65mmol/L, from 0.03 to 3.91mmol/L respectively are also potentially produced or consumed through various redox

  14. Assessment of photon attenuation characteristics of commercial lead bricks

    International Nuclear Information System (INIS)

    Lead is often used as a shielding material due to its high density and atomic number. Although photon attenuation data are available in literature, it is necessary to test the commercially fabricated lead shielding material experimentally for its radiation shielding efficiency and compare with theoretically computed values of pure lead before putting in to regular use. In the present work, attenuation characteristics of lead supplied by a manufacturing firm was studied for five energy lines

  15. Assessment and evaluation of surface contamination: where is the problem?

    International Nuclear Information System (INIS)

    Starting from the discussions and misunderstandings about contamination values found recently on transport casks, the problems are pointed out that result from the rigid definition of 'limit values' for surface contamination in the Federal Republic of Germany in connection with the measurement uncertainty by smear and wipe tests on complex surfaces like transport casks. This is compared with the methods and experiences from our Swiss colleagues. Moreover, a survey is given on today's measuring practices and instruments for assessment of surface contamination. (orig.)

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

    Science.gov (United States)

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

    2013-04-01

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

  17. A biogeochemical transport model to simulate the attenuation of chlorinated hydrocarbon contaminant fluxes across the groundwater-surface water interface

    DEFF Research Database (Denmark)

    Malaguerra, Flavio; Binning, Philip John; Albrechtsen, Hans-Jørgen

    2009-01-01

    Chlorinated hydrocarbons originating from point sources are amongst the most prevalent contaminants of ground water and surface water resources. Riparian zones may play an important role in the attenuation of contaminant concentrations when contaminant plumes flow from groundwater to surface water...... because of the occurrence of redox gradients, strongly reductive conditions and high biological activity. In order to meet the expectations of the EU Water Framework Directive, an evaluation of the impact of such plumes on surface water is needed. The aim of this work is to develop a groundwater transport...... and biogeochemical transformation model of the discharge of a TCE plume into a stream, and to determine which parameters most strongly affect pollutant discharge concentrations. Here biological kinetics and the interaction with the soil matrix are implemented in PHREEQC. The ability of PHREEQC to deal...

  18. Assessment of contamination in the Shuttle bay

    Science.gov (United States)

    Jeffery, J. A.; Maag, C. R.; Seastrom, J. W.; Weber, M. F.

    1982-01-01

    The results of an analytical study to determine the contamination potential of the Galileo probe instruments while in the STS bay are presented. The study covered conditions wherein the instruments weren't covered, covers were used with vent paths of varying sizes, and if the instruments were sealed and a nitrogen purge was employed. The contamination limits for each of the Galileo instruments are considered. Analytic approximations are devised for the diffusion of particles from surfaces and materials in the Shuttle bay during the ascent phase, using Fick's second law of diffusion. It is recommended that an instrument purge be implemented during the first 15 min of Shuttle flight in order to carry the contaminants from both the bay fixtures and from the instruments into space. Covers are suggested as necessary for the most sensitive instruments.

  19. Preliminary Assessment Of SIRE's Potential For Contamination

    Science.gov (United States)

    Mah, D. L.; Muscari, J. A.

    1981-07-01

    This paper presents the results of a contamination analysis and computer modeling study performed for the Space Infrared Experiment (SIRE) using the Space Transport System (STS) Shuttle Orbiter as the launch vehicle for the proposed seven-day sortie mission. These results will provide an accurate description of the deposition levels on the telescope primary mirror and of the molecular number column density (NCD) along the telescope line-of-sight. The planned Helium Purge System was assumed not to be operating. The contri-bution to the contamination environment of any cargo element, other than SIRE and its pallet, was not considered in this study. The study considers five potential contamination sources, including the flash evaporator vent effluents and the vernier reaction control system (VCS) engines plume constituents.

  20. SURROGATE SPECIES IN ASSESSING CONTAMINANT RISK FOR ENDANGERED FISHES

    Science.gov (United States)

    Rainbow trout, fathead minnows, and sheepshead minnows were tested as surrogate species to assess contaminant risk for 17 endangered fishes and one toad species. Acute toxicity tests were conducted with carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin in accord...

  1. Attenuation of Metal Bioavailability in Acidic Multi-Metal Contaminated Soil Treated with Fly Ash and Steel Slag

    Institute of Scientific and Technical Information of China (English)

    QIU Hao; GU Hai-Hong; HE Er-Kai; WANG Shi-Zhong; QIU Rong-Liang

    2012-01-01

    A pot experiment was conducted with multi-metal (Pb,Cd,Cu,and Zn) contaminated acidic soil to investigate changes in available metal burden resulting from the application of industrial wastes (fly ash and steel slag).The efficiency of amendmentsinduced metal stabilization was evaluated by diffusive gradients in thin films (DGT),sequential extraction,and plant uptake.The stability of remediation was assessed by an acidification test and by chemical equilibrium modeling.Addition of fly ash (20 g kg-1) and steel slag (3 g kg-1 ) resulted in similar increase in soil pH.Both amendments significantly decreased the concentrations of metals measured with DGT (CDGT) and the metal uptake by Oryza sativa L.Significant correlations were found between CDGT and the concentration of a combination of metal fractions (exchangeable,bound to carbonates,and bound to Fe/Mn oxides),unraveling the labile species that participate in the flux of metal resupply.The capability of metal resupply,as reflected by the R (ratio of CDGT to pore water metal concentration) values,significantly decreased in the amended soils.The CDGT correlated well with the plant uptake,suggesting that DGT is a good indicator for bioavailability.Acidification raised the extractable metal concentration in amended soil but the concentration did not return to the pre-amendment level.Equilibrium modeling indicated that the soil amendments induced the precipitation of several Fe,Al and Ca minerals,which may play a positive role in metal stabilization.Chemical stabilization with alkaline amendments could be an effective and stable soil remediation strategy for attenuating metal bioavailability and reducing plant metal uptake.

  2. Natural attenuation assessment of multiple VOCs in a deep vadose zone

    International Nuclear Information System (INIS)

    The fate of six volatile organic compounds (VOC) in a 150-meter deep vadose zone was examined in support of a RCRA Corrective Measures Study of the Chemical Waste Landfill at Sandia National Laboratories, Albuquerque, New Mexico. The study focused on the modeling of potential future transport of the VOCs to exposure media upon the completion of two separate voluntary corrective measures--soil vapor extraction and landfill excavation--designed to significantly reduce contaminant levels in subsurface soils. modeling was performed with R-UNSAT, a finite-difference simulator that was developed by the U.S. Geological Survey. R-UNSAT facilitated a relatively unique and comprehensive assessment of vapor transport because it (1) simulated the simultaneous movement of all six VOCs, taking into account each constituent's diffusion coefficient as affected by its mole fraction within a mixture of chemicals, and (2) permitted simultaneous assessment of risk to human health via volatilization (air) and drinking water (groundwater) pathways. Modeling results suggested that monitored natural attenuation would represent a viable remedial alternative at the landfill after both voluntary corrective measures were completed

  3. Ultrasound attenuation computed tomography assessment of PAGAT gel dose

    International Nuclear Information System (INIS)

    Ultrasound has been previously investigated as an alternative readout method for irradiated polymer gel dosimeters, with authors reporting varying dose responses. We extend previous work utilizing a new computed tomography ultrasound scanner comprising of two identical 5 MHz, 128-element linear-array ultrasound transducers, co-axially aligned and submerged in water as a coupling agent, with rotational of the gel dosimeter between the transducers facilitated by a robotic arm. We have investigated the dose-dependence of both ultrasound bulk attenuation and broadband ultrasound attenuation (BUA) for the PAGAT gel dosimeter. The ultrasound bulk attenuation dose sensitivity was found to be 1.46  ±  0.04 dB m −1 Gy −1, being in agreement with previously published results for PAG and MAGIC gels. BUA was also found to be dose dependent and was measured to be 0.024  ±  0.003 dB MHz −1 Gy −1; the advantage of BUA being its insensitivity to frequency-independent attenuation mechanisms including reflection and refraction, thereby minimizing image reconstruction artefacts. (note)

  4. Agricultural soils potentially contaminated: risk assessment procedure case studies

    Directory of Open Access Journals (Sweden)

    Eleonora Beccaloni

    2010-01-01

    Full Text Available At the moment, the health-environmental risk analysis is used to decision-making targets in the contaminated sites management; this procedure allows to assess the quantitative health risk related to the pollutants presence in environmental compartments, as soil and waters. As regards potentially contaminated agricultural soils, the ingestion of food from vegetable and/or animal source, produced inside the contaminated area, is the most suitable way to assess the health risk. As an official procedure to this assessment is not available, the National Institute for Health (Istituto Superiore di Sanità, ISS has worked out an operating procedure, organized into several phases, depending on the available specific-site know-how. In this document, agricultural soils potentially contaminated in two sites have been studied; the sites are the following: Brescia Caffaro and Torviscosa.

  5. A remediation strategy based on active phytoremediation followed by natural attenuation in a soil contaminated by pyrite waste

    International Nuclear Information System (INIS)

    Phytoremediation of metal-polluted soils can be promoted by the proper use of soil amendments and agricultural practices. A 4-year phytoremediation programme was applied to a site affected by the toxic spill of pyrite residue at Aznalcollar (Spain) in 1998, contaminated with heavy metals (Zn, Cu, Pb, Cd) and arsenic. This consisted of active phytoremediation, using organic amendments (cow manure and compost) and lime and growing two successive crops of Brassica juncea (L.) Czern., followed by natural attenuation without further intervention. Changes in soil pH, extractable metal and As concentrations, organic carbon content and microbial biomass was evaluated. The initial oxidation of metal sulphides from pyrite residues released soluble metals and reduced soil pH to extremely acidic values (mean 4.1, range 2.0-7.0). The addition of lime (up to 64 t ha-1) increased soil pH to adequate values for plant growth, resulting in a significant decrease in DTPA-extractable metal concentrations in all plots. Natural attenuation phase showed also a decrease in extractable metals. Organic treatments increased the soil total organic carbon, which led to higher values of microbial biomass (11.6, 15.2 and 14.9 g kg-1 TOC and 123, 170 and 275 μg g-1 biomass-C in control, compost and manure plots, respectively). Active phytoremediation followed by natural attenuation, was effective for remediation of this pyrite-polluted soil. - The addition of lime and organic amendments decreased heavy metal solubility and promoted Natural attenuation of a recently-contaminated soil

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

    Directory of Open Access Journals (Sweden)

    McCafferty P. B.

    2013-04-01

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

  7. Tier 1 Ecological Risk Assessment of a Contaminated Rail Corridor

    OpenAIRE

    Steer, Scott

    2004-01-01

    A screening level ecological risk assessment (ERA) was conducted for a contaminated rail corridor in British Columbia. The purpose of the ERA was to demonstrate the utility of British Columbia Tier 1 ERA methodology for identifying contaminated sites with unacceptable ecological risks requiring remediation andor risk management. The methodology applies a weight of evidence approach to characterize ecological risks with risk quotients and site observations serving as the two lines of evidence....

  8. Life cycle assessment of Polychlorinated Biphenyl contaminated soil remediation processes

    OpenAIRE

    Busset, Guillaume; Sangely, Matthieu; Montréjaud-Vignoles, Mireille; Thannberger, Laurent; Sablayrolles, Caroline

    2012-01-01

    Goal and scope. A life-cycle assessment (LCA) was performed to evaluate the environmental impacts of the remediation of industrial soils contaminated by polychlorobiphenyl (PCB). Two new bioremediation treatment options were compared with the usual incineration process. In this attributional LCA, only secondary impacts were considered. The contaminated soil used for the experiments contained 200 mg of PCB per kg. Methods. Three off-site treatments scenarios were studied: 1) bioremediation...

  9. Passive sampling methods for contaminated sediments: Risk assessment and management

    OpenAIRE

    Greenberg, Marc S; Chapman, Peter M.; Allan, Ian J.; Anderson, Kim A.; Apitz, Sabine E.; Beegan, Chris; Bridges, Todd S; Brown, Steve S; Cargill, John G; McCulloch, Megan C; Menzie, Charles A; Shine, James P.; Parkerton, Thomas F

    2014-01-01

    This paper details how activity-based passive sampling methods (PSMs), which provide information on bioavailability in terms of freely dissolved contaminant concentrations (C free), can be used to better inform risk management decision making at multiple points in the process of assessing and managing contaminated sediment sites. PSMs can increase certainty in site investigation and management, because C free is a better predictor of bioavailability than total bulk sediment concentration (C t...

  10. Using diatom taxonomic diversity to assess herbicide contamination in rivers

    OpenAIRE

    Marcel, Rémy; Bouchez, Agnes; Rimet, Frédéric,

    2011-01-01

    The increasing contamination by micropollutants in freshwater systems has become a major problem in modern societies, giving rise to toxicological, sanitary and economical concerns. In 2010 the French government adopted a plan for a 50% reduction over 10 years in the use of pesticides which promotes research on contamination monitoring. Diatom bio-indication tools in rivers have been standardized and normalized (AFNOR NFT 90 354 ; CEN – EN 13946 & EN 14407) and are adapted to assess nutrient ...

  11. Assessment of human skin decontamination from radioactive contamination

    International Nuclear Information System (INIS)

    A suitable and practicable means for assessing skin decontamination and percutaneous adsorption of radioactive skin contaminants is developed by comparing the streams of beta-particles and gamma-quanta characterizing the penetration and distribution of radioactive skin contaminants. The principal requirements which a preparation for human skin decontaminants should meet are: effectiveness of the preparation, minimal percutaneous absorption, broad activity spectrum on compounds and radionuclides, preservation of integrity of the treated skin and a simple method of use of the decontaminant. (author)

  12. Integrated modelling for assessing the risk of TCE groundwater contamination to human and surface water ecosystems

    DEFF Research Database (Denmark)

    McKnight, Ursula S.; Funder, Simon Goltermann; Finkel, Michael;

    2009-01-01

    management tools designed to work with sparse data sets from preliminary site assessments are needed which can explicitly link contaminant point sources with groundwater, surface water and ecological impacts. Here, a novel integrated modelling approach was employed for evaluating the impact of a TCE....... The model is tested on a Danish case study involving a 750 m long TCE groundwater plume discharging into a stream. Although little data exists regarding the source zone, measured TCE concentrations (in the mgL-1 range) reveal the presence of separate phase of contaminant and show that the source will...... not be depleted for many decades. However, measured and future predicted TCE concentrations in surface water were found to be below human health risk management targets. Volatilization was found to rapidly attenuate TCE concentrations in the surface water. Thus, only a 300 m stream reach failed to...

  13. Towards the assessment and management of contaminated dredged materials.

    Science.gov (United States)

    Agius, Suzanne J; Porebski, Linda

    2008-04-01

    Environment Canada's Disposal at Sea Programme hosted the Contaminated Dredged Material Management Decisions Workshop in Montreal, Quebec, Canada, on 28-30 November 2006. The workshop brought together over 50 sediment assessment and management experts from academic, industrial, and regulatory backgrounds and charged them with drafting a potential framework to assess contaminated dredged materials and compare the risks of various disposal alternatives. This article summarizes the recommendations made during the workshop concerning the development of sediment assessment tools, the interpretation of these tools, and the essential attributes of a comparative risk assessment process. The major outcomes of the workshop include a strong recommendation to develop a national dredging or sediment management strategy, a potential decision-making framework for the assessment of dredged materials and comparative risk assessment of disposal options, and the expansion of minimum sediment characterization requirements for nonroutine disposal permit applications. PMID:17994915

  14. Recurrent and sporadic Listeria monocytogenes contamination in alheiras represents considerable diversity, including virulence-attenuated isolates

    OpenAIRE

    Felício, M. T. S.; Hogg, T.; GIBBS, P.; Teixeira, P; Wiedmann, M.

    2007-01-01

    Microbiological characterization of alheiras, traditional smoked meat sausages produced in northern Portugal, had previously shown that more than 60% of the lots analyzed were contaminated with Listeria monocytogenes at levels higher than 100 CFU/g. In order to better understand L. monocytogenes contamination patterns in alheiras, we characterized 128 L. monocytogenes isolates from alheiras using a variety of subtyping techniques (i.e., molecular serotyping; arsenic, cadmium, and tetracycline...

  15. 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.

  16. Assessment of low levels of radioactive contamination

    International Nuclear Information System (INIS)

    This report describes a general methodology for the verification and clearance of sites contaminated with radioactive materials; general expressions for the risk or health detriment are derived. Techniques are developed, using Bayesian decision theory, to optimize the resources allocated to a site monitoring procedure, and to construct the probability distribution of the spatial distribution of specific activity within a site. A technique is also developed to determine the probability that a localized source of specified characteristics will not be detected by the monitoring procedure employed. The application of these techniques is illustrated by means of simple examples. This report confirms that a very large number of measurements are needed if a source of localized activity is to be detected with a high probability, and demonstrates how prior information about past radiological practices might be used to increase the probability of detection. Proposals are made for a programme of research to determine whether or not representative sites can be verified using current measuring techniques. (author)

  17. Assessing sediment contamination using six toxicity assays

    Directory of Open Access Journals (Sweden)

    Allen G. BURTON Jr.

    2001-08-01

    Full Text Available An evaluation of sediment toxicity at Lake Orta, Italy was conducted to compare a toxicity test battery of 6 assays and to evaluate the extent of sediment contamination at various sediment depths. Lake Orta received excessive loadings of copper and ammonia during the 1900’s until a large remediation effort was conducted in 1989-90 using lime addition. Since that time, the lake has shown signs of a steady recovery of biological communities. The study results showed acute toxicity still exists in sediments at a depth of 5 cm and greater. Assays that detected the highest levels of toxicity were two whole sediment exposures (7 d using Hyalella azteca and Ceriodaphnia dubia. The MicrotoxR assay using pore water was the third most sensitive assay. The Thamnotox, Rototox, Microtox solid phase, and Seed Germination-Root Elongation (pore and solid phase assays showed occasional to no toxicity. Based on similarity of responses and assay sensitivity, the two most useful assays were the C. dubia (or H. azteca and Microtox pore water. These assays were effective at describing sediment toxicity in a weight-of-evidence approach.

  18. Assessment of sediment contamination in Casco Bay, Maine, USA

    International Nuclear Information System (INIS)

    The current status of contaminant concentrations in Casco Bay, decadal trends of these contaminants and changes in their geographical distribution are assessed using sediment samples collected approximately 10 years apart. In general, regulated contaminants appeared to be decreasing in concentration. Total PAH and dioxins/furans concentrations did not significantly change over this period. Total organochlorine pesticides, 4,4-DDE, 4,4-DDD, total DDT, PCB, tributyltin and total butyltin decreased in concentration. Trace element concentrations in sediments decreased at the majority of the sampling sites for chromium, nickel, and selenium while arsenic, cadmium, copper, lead, mercury, silver, and zinc remained relatively constant. None of the contaminants measured has increased by more than a factor of 2. Selected sites located in the Inner Bay, where concentrations are higher and new inputs were more likely, showed increased concentrations of contaminants. Most contaminants were not found at concentrations expected to adversely affect sediment biota based on ERL/ERM guidelines. - Sediment studies indicate decadal decreases for many chemical contaminants in Casco Bay

  19. Using ultrasonic attenuation for assessing the fatigue damage of concrete

    International Nuclear Information System (INIS)

    The results from cyclic loading tests indicate that damage accumulation as measured by pulse attenuation during cyclic loading is not linear, particularly during the initial cycles. The crack growth results obtained may be used for ascertaining the extent of damage in a in-situ structure using the following procedure: The ultrasonic waveforms obtained from a damaged region can first be compared with that obtained from the same region initially to yield a damage coefficient. Then the calibration charts obtained from laboratory specimens may be used to predict the extent of damage due to cyclic loading. The proposed method can also easily be extended to predict the deterioration due to shrinkage, creep and other environmental effects as long as their effect is to produce cracking in the concrete. (orig./HP)

  20. Incorporating Contaminant Bioavailability into Sediment Quality Assessment Frameworks

    Science.gov (United States)

    The recently adopted sediment quality assessment framework for evaluating bay and estuarine sediments in the State of California incorporates bulk sediment chemistry as a key line of evidence(LOE) but does not address the bioavailability of measured contaminants. Thus, the chemis...

  1. Nitrate contamination risk assessment in groundwater at regional scale

    Science.gov (United States)

    Daniela, Ducci

    2016-04-01

    Nitrate groundwater contamination is widespread in the world, due to the intensive use of fertilizers, to the leaking from the sewage network and to the presence of old septic systems. This research presents a methodology for groundwater contamination risk assessment using thematic maps derived mainly from the land-use map and from statistical data available at the national institutes of statistic (especially demographic and environmental data). The potential nitrate contamination is considered as deriving from three sources: agricultural, urban and periurban. The first one is related to the use of fertilizers. For this reason the land-use map is re-classified on the basis of the crop requirements in terms of fertilizers. The urban source is the possibility of leaks from the sewage network and, consequently, is linked to the anthropogenic pressure, expressed by the population density, weighted on the basis of the mapped urbanized areas of the municipality. The periurban sources include the un-sewered areas, especially present in the periurban context, where illegal sewage connections coexist with on-site sewage disposal (cesspools, septic tanks and pit latrines). The potential nitrate contamination map is produced by overlaying the agricultural, urban and periurban maps. The map combination process is very easy, being an algebraic combination: the output values are the arithmetic average of the input values. The groundwater vulnerability to contamination can be assessed using parametric methods, like DRASTIC or easier, like AVI (that involves a limited numbers of parameters). In most of cases, previous documents produced at regional level can be used. The pollution risk map is obtained by combining the thematic maps of the potential nitrate contamination map and the groundwater contamination vulnerability map. The criterion for the linkages of the different GIS layers is very easy, corresponding to an algebraic combination. The methodology has been successfully

  2. An integrated model for assessing the risk of TCE groundwater contamination to human receptors and surface water ecosystems

    DEFF Research Database (Denmark)

    McKnight, Ursula S.; Funder, S.G.; Rasmussen, J.J.;

    2010-01-01

    accomplished by coupling the system dynamics-based decision support system CARO-PLUS to the aquatic ecosystem model AQUATOX using an analytical volatilization model for the stream. The model was applied to a case study where a TCE contaminated groundwater plume is discharging to a stream. The TCE source will...... not be depleted for many decades, however measured and predicted TCE concentrations in surface water were found to be below human health risk management targets. Volatilization rapidly attenuates TCE concentrations in surface water. Thus, only a 300 m stream reach fails to meet surface water quality...... criteria. An ecological risk assessment found that the TCE contamination did not impact the stream ecosystem. Uncertainty assessment revealed hydraulic conductivity to be the most important site-specific parameter. These results indicate that contaminant plumes with μgL-1 concentrations of TCE entering...

  3. Application of natural attenuation to ground water contaminated by phenoxy acid herbicides at an old landfill in Sjoelund

    DEFF Research Database (Denmark)

    Tuxen, Nina; Ejlskov, P.; Albrechtsen, Hans-Jørgen; Ask Reitzel, Lotte; Pedersen, J.K.; Bjerg, Poul Løgstrup

    2003-01-01

    Investigations of geology, hydrogeology, and ground water chemistry in the aquifer downgradient from Sjoelund Landfill, Denmark, formed the basis for an evaluation of natural attenuation as a remediation technology for phenoxy acid herbicides at the site. Concentrations of phenoxy acids were up to...... 65 mug/L in the ground water, primarily 4-chlor-2-methylphenoxypropionic acid (MCPP) and 2,4-dichlorophenoxypropionic acid (dichlorprop). Mass removal of the phenoxy acids was shown within 50 to 100 m of the landfill by calculation of contaminant fluxes passing transects at three distances. There was...... accordance between increasing oxygen concentrations and decreasing phenoxy acid concentrations with distance from the landfill, indicating that aerobic degradation was a major mass removal process. Presence of high concentrations of putative anaerobic phenoxy acid metabolites suggested that anaerobic...

  4. Monitored natural attenuation (MNA) of contaminated soils: state of the art in Europe--a critical evaluation.

    Science.gov (United States)

    Declercq, I; Cappuyns, V; Duclos, Y

    2012-06-01

    The use of natural attenuation (NA) processes for contaminated site cleanup and remediation has been gaining more attention over the last few years. However, the need for an inventory of the existing information concerning monitored natural attenuation (MNA), including the existing return on experience, has been sounding increasingly louder over recent years as well. This paper will focus on the application of MNA throughout Europe. First, a literature study and a survey were performed in order to collect all available data on both qualitative and quantitative aspects of MNA. Secondly, a questionnaire was created and sent out to experts in the field of regulation and research from six countries, including Finland, Spain, and the UK. Thirdly, further contributions from a SNOWMAN workshop concerning MNA (November 7th, 2011, Paris) were included in this paper. The result is a state of the art concerning MNA for several countries, including the legal framework and existing protocols, a comparison between different countries, and an overview of some existing MNA cases throughout Europe combined with a discussion on relevant aspects related to "return on experience". The results demonstrate that MNA is now considered to be a conventional remediation technique in most countries that were included in this study. Although MNA is currently being applied for the remediation of contaminated sites, some countries still don't recognise it as an official remediation technique (e.g. Finland). This study also confirms and illustrates the differences concerning the MNA approach that exists between different countries, as well as the differences in application levels. However, it is important to note that at the same time a certain level of coherence exists concerning the MNA approach, e.g. with regard to the importance of biodegradation processes. Furthermore, the main outcome of this study emphasises the clear need to systematically collect and share information concerning existing

  5. Benzene-contaminated groundwaters - Transport parameters and isotopic evidence for natural attenuation

    International Nuclear Information System (INIS)

    The area of investigation is located on the site of a former hydrogenation plant in Zeitz (Saxonia-Anhalt, Germany). The plant was founded in 1938 to produce gasoline and lubricants originally for the German war industry and was subject of severe bomb strikes in 1944 and 1945 spilling about 250 m3 hydrocarbons into soil. In 1946 it was rebuilt and in the beginning of the 1960's upgraded with a benzene production plant in the eastern part of hydrogenation plant. From 1963 till 1990 the latter produced more than 750,000 t of benzene with maximum production rate in 1979 (79,000 t per year). Leaks and production accidents contaminated groundwater. Contaminations were found in two aquifers

  6. Assisted attenuation of a soil contaminated by diuron using hydroxypropyl-β-cyclodextrin and organic amendments

    OpenAIRE

    Rubio Bellido, Marina; Madrid Díaz, Fernando; Morillo González, Esmeralda; Villaverde Capellán, J.

    2014-01-01

    Diuron desorption and mineralisation were studied on an amended and artificially contaminated soil. The amendments used comprised two different composted organic residues i.e., sewage sludge (SS) mixed with pruning wastes, and urban solid residues (USR), and two different solutions (with inorganic salts as the micronutrients and hydroxypropyl-β-cyclodextrin (HPBCD)). After applying micronutrients to activate the soil flora, 15.5% mineralisation could be reached after 150 days, indicating that...

  7. Ecological aspects of environmental assessment of contaminated areas

    International Nuclear Information System (INIS)

    When large landscapes are contaminated by radionuclides released from nuclear activities, physical processes, such as atmospheric and hydrological transport may move the radioactive materials over large distances resulting in direct external exposure of man and organisms. Of equal concern are ecological processes that may result in internal exposure when contaminated drinking water or foodstuffs are ingested. This paper provides an overview of the modeling of radionuclide movement through defined ecological pathways, describes some ecological problems at remediated sites, and briefly reviews effects of environmental radiation on terrestrial and aquatic biota. This paper also descries pathways that should be considered when conducting environmental dose assessments for radionuclides released to the environment

  8. A Contamination Vulnerability Assessment for the Sacramento Area Groundwater Basin

    Energy Technology Data Exchange (ETDEWEB)

    Moran, J E; Hudson, G B; Eaton, G F; Leif, R

    2004-03-10

    In response to concerns expressed by the California Legislature and the citizenry of the State of California, the State Water Resources Control Board (SWRCB), implemented a program to assess groundwater quality, and provide a predictive capability for identifying areas that are vulnerable to contamination. The program was initiated in response to concern over public supply well closures due to contamination by chemicals such as MtBE from gasoline, and solvents from industrial operations. As a result of this increased awareness regarding groundwater quality, the Supplemental Report of the 1999 Budget Act mandated the SWRCB to develop a comprehensive ambient groundwater-monitoring plan, and led to the initiation of the Ambient Groundwater Monitoring and Assessment (GAMA) Program. The primary objective of the GAMA Program is to assess the water quality and to predict the relative susceptibility to contamination of groundwater resources throughout the state of California. Under the GAMA program, scientists from Lawrence Livermore National Laboratory (LLNL) collaborate with the SWRCB, the U.S. Geological Survey, the California Department of Health Services (DHS), and the California Department of Water Resources (DWR) to implement the groundwater assessment program in cooperation with local water purveyors. In 2001 and 2002, LLNL carried out this vulnerability study in the groundwater basin of Sacramento suburban area, located to the north of the American River and to the east of the Sacramento River. The goal of the study is to provide a probabilistic assessment of the relative vulnerability of groundwater used for the public water supply to contamination from surface sources. This assessment of relative contamination vulnerability is made based on the results of two types of analyses that are not routinely carried out at public water supply wells: ultra low-level measurement of volatile organic compounds (VOCs), and groundwater age dating (using the tritium-helium-3

  9. Identification of contaminants of concern Columbia River Comprehensive Impact Assessment

    International Nuclear Information System (INIS)

    The Columbia River Comprehensive Impact Assessment (CRCIA) Project at the Pacific Northwest Laboratory (PNL) is evaluating the current human and ecological risks from contaminants in the Columbia River. The risks to be studied are those attributable to past and present activities on the Hanford Site. The Hanford Site is located in southcentral Washington State near the town of Richland. Human risk from exposure to radioactive and hazardous materials will be addressed for a range of river use options. Ecological risk will be evaluated relative to the health of the current river ecosystem. The overall purpose of the project is to determine if enough contamination exists in the Columbia River to warrant cleanup actions under applicable environmental regulations. This report documents an initial review, from a risk perspective, of the wealth of historical data concerning current or potential contamination in the Columbia River. Sampling data were examined for over 600 contaminants. A screening analysis was performed to identify those substances present in such quantities that they may pose a significant human or ecological risk. These substances will require a more detailed analysis to assess their impact on humans or the river ecosystem

  10. Quantitative assessment of in vivo breast masses using ultrasound attenuation and backscatter.

    Science.gov (United States)

    Nam, Kibo; Zagzebski, James A; Hall, Timothy J

    2013-04-01

    Clinical analysis of breast ultrasound imaging is done qualitatively, facilitated with the ultrasound breast imaging-reporting and data system (US BI-RADS) lexicon, which helps to standardize imaging assessments. Two descriptors in that lexicon, "posterior acoustic features" and the "echo pattern" within a mass, are directly related to quantitative ultrasound (QUS) parameters, namely, ultrasound attenuation and the average backscatter coefficient (BSC). The purpose of this study was to quantify ultrasound attenuation and backscatter in breast masses and to investigate these QUS properties as potential differential diagnostic markers. Radio frequency (RF) echo signals were from patients with breast masses during a special ultrasound imaging session prior to core biopsy. Data were also obtained from a well characterized phantom using identical system settings. Masses include 14 fibroadenomas and 10 carcinomas. Attenuation for the acoustic path lying proximal to the tumor was estimated offline using a least squares method with constraints. BSCs were estimated using a reference phantom method (RPM). The attenuation coefficient within each mass was assessed using both the RPM and a hybrid method, and effective scatterer diameters (ESDs) were estimated using a Gaussian form factor model. Attenuation estimates obtained with the RPM were consistent with estimates done using the hybrid method in all cases except for two masses. The mean slope of the attenuation coefficient versus frequency for carcinomas was 20% greater than the mean slope value for the fibroadenomas. The product of the attenuation coefficient and anteroposterior dimension of the mass was computed to estimate the total attenuation for each mass. That value correlated well with the BI-RADS assessment of "posterior acoustic features" judged qualitatively from gray scale images. Nearly all masses were described as "hypoechoic," so no strong statements could be made about the correlation of echo pattern

  11. Assessment of atmospheric microbial contamination in a mobile dental unit

    OpenAIRE

    Shivakumar K; Prashant G; Madhu Shankari G; Subba Reddy V; Chandu G

    2007-01-01

    Introduction: Bioaerosols are important considerations in infection control as well as in occupational health. Bioaerosols may carry potentially hazardous microbes, viruses, fungi, allergens, and other toxic substances that may harm the dental operator, patient, and the dental assistant by causing nosocomial infections. Objective: To assess the level of atmospheric microbial contamination before, during, and after dental treatment procedures in the dental operatory of a mobile dental unit...

  12. Laboratory measurements of contaminant attenuation of uranium mill tailings leachates by sediments and clay liners

    International Nuclear Information System (INIS)

    We discuss FY82 progress on the development of laboratory tools to aid in the prediction of migration potential of contaminants present in acidic uranium mill tailings leachate. Further, empirical data on trace metal and radionuclide migration through a clay liner are presented. Acidic uranium mill tailings solution from a Wyoming mill was percolated through a composite sediment called Morton Ranch Clay liner. These laboratory columns and subsequent sediment extraction data show: (1) As, Cr, Pb, Ag, Th and V migrate very slowly; (2) U, Cd, Ni, Zn, Fe, Mn and similar transition metals are initially immobilized during acid neutralization but later are remobilized as the tailings solution exhausts the clay liner's acid buffering capacity. Such metals remain immobilized as long as the effluent pH remains above a pH value of 4 to 4.5, but they become mobile once the effluent pH drops below this range; and (3) fractions of the Se and Mo present in the influent tailings solution are very mobile. Possible controlling mechanisms for the pH-dependent immobilization-mobilization of the trace metals are discussed. More study is required to understand the controlling mechanisms for Se and Mo and Ra for which data were not successfully collected. Using several column lengths (from 4.5 to 65 cm) and pore volume residence times (from 0.8 to 40 days) we found no significant differences in contaminant migration rates or types and extent of controlling processes. Thus, we conclude that the laboratory results may be capable of extrapolation to actual disposal site conditions

  13. Laboratory measurements of contaminant attenuation of uranium mill tailings leachates by sediments and clay liners

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R.J.; Peterson, S.R.; Gee, G.W.

    1983-04-01

    We discuss FY82 progress on the development of laboratory tools to aid in the prediction of migration potential of contaminants present in acidic uranium mill tailings leachate. Further, empirical data on trace metal and radionuclide migration through a clay liner are presented. Acidic uranium mill tailings solution from a Wyoming mill was percolated through a composite sediment called Morton Ranch Clay liner. These laboratory columns and subsequent sediment extraction data show: (1) As, Cr, Pb, Ag, Th and V migrate very slowly; (2) U, Cd, Ni, Zn, Fe, Mn and similar transition metals are initially immobilized during acid neutralization but later are remobilized as the tailings solution exhausts the clay liner's acid buffering capacity. Such metals remain immobilized as long as the effluent pH remains above a pH value of 4 to 4.5, but they become mobile once the effluent pH drops below this range; and (3) fractions of the Se and Mo present in the influent tailings solution are very mobile. Possible controlling mechanisms for the pH-dependent immobilization-mobilization of the trace metals are discussed. More study is required to understand the controlling mechanisms for Se and Mo and Ra for which data were not successfully collected. Using several column lengths (from 4.5 to 65 cm) and pore volume residence times (from 0.8 to 40 days) we found no significant differences in contaminant migration rates or types and extent of controlling processes. Thus, we conclude that the laboratory results may be capable of extrapolation to actual disposal site conditions.

  14. Contaminants in milk and impact of heating: An assessment study

    Directory of Open Access Journals (Sweden)

    Vandana Awasthi

    2012-01-01

    Full Text Available Background: The major contaminants usually encountered in milk and milk products include pesticide residues, heavy metals, and aflatoxin M1 (AFM1. Primarily, milk get contaminated before milching, from the cattle feed, from sources/materials used during the processing of milk as well as improper handling of the milk during the pre- and postprocessing period. Objective: The purpose of this study was to evaluate the effect of household practices on milk contaminants. Materials and Methods: Samples of pasteurized as well as unpasteurized milk (Vendor′s milk were analyzed for AFM1, pesticide residues, and heavy metals. Simulating the household practices, the impact of boiling on these contaminants was assessed. Results: The contaminant Aflatoxin M1 (AFM1 was detected at a concentration ranging from 0.071-0.075 ppb in unpasteurized as well as pasteurized milk samples analyzed during the course of study. Moreover, boiling had no impact on the quantity of AFM1 present in the milk. Pesticides and heavy metal contents were found to be within acceptable limits in all the milk samples tested. Conclusion: Mycotoxins especially aflatoxins in cattle feed and their consequential presence in milk and milk products is a serious concern world over as they are reported carcinogens. These fungal toxins are resistant to high temperatures and may lead to various health hazards. Preventive steps must be taken at each stage to ensure good quality of milk and milk products free from these contaminants. Awareness programs and education for the dairy farmers and milk processors may be helpful in this regard.

  15. A national-scale assessment of micro-organic contaminants in groundwater of England and Wales.

    Science.gov (United States)

    Manamsa, Katya; Crane, Emily; Stuart, Marianne; Talbot, John; Lapworth, Dan; Hart, Alwyn

    2016-10-15

    A large variety of micro-organic (MO) compounds is used in huge quantities for a range of purposes (e.g. manufacturing, food production, healthcare) and is now being frequently detected in the aquatic environment. Interest in the occurrence of MO contaminants in the terrestrial and aquatic environments continues to grow, as well as in their environmental fate and potential toxicity. However, the contamination of groundwater resources by MOs has a limited evidence base compared to other freshwater resources. Of particular concern are newly 'emerging contaminants' such as pharmaceuticals and lifestyle compounds, particularly those with potential endocrine disrupting properties. While groundwater often has a high degree of protection from pollution due to physical, chemical and biological attenuation processes in the subsurface compared to surface aquatic environments, trace concentrations of a large range of compounds are still detected in groundwater and in some cases may persist for decades due to the long residence times of groundwater systems. This study provides the first national-scale assessment of micro-organic compounds in groundwater in England and Wales. A large set of monitoring data was analysed to determine the relative occurrence and detected concentrations of different groups of compounds and to determine relationships with land-use, aquifer type and groundwater vulnerability. MOs detected including emerging compounds such as caffeine, DEET, bisphenol A, anti-microbial agents and pharmaceuticals as well as a range of legacy contaminants including chlorinated solvents and THMs, petroleum hydrocarbons, pesticides and other industrial compounds. There are clear differences in MOs between land-use types, particularly for urban-industrial and natural land-use. Temporal trends of MO occurrence are assessed but establishing long-term trends is not yet possible. PMID:27073165

  16. Assessment of sites concerning radioactive contamination during preparation of a Contamination Site Register

    International Nuclear Information System (INIS)

    Experience gained since 1990 in the new, but also old German Federal States has shown that there are radioactive contaminated sites beside the legacies of uranium mining in Germany which caused exposures exceeding the radiation protection limits for members of the public. The reason for this situation is that radioactivity has been excluded in the compilation of the register for potentially hazardous sites that are prepared routinely in the context of soil protection assessments. Moreover, the information contained in these registers is not yet evaluated regarding aspects of radioactivity. In many cases, the information existing at the soil protection authorities needs only to be additionally filtered in order to identify potentially hazardous sites for radioactive contamination. For that reason, the working group ''Natural radioactivity'' (AKNAT) of the German-Swiss Radiation Protection Association developed a specific catalogue of business branches that provides indications for radioactive legacies.

  17. HUMAN HEALTH RISK ASSESSMENT OF CONTAMINATED SOILS WITH CARGINOGEN POLLUTANTS

    Directory of Open Access Journals (Sweden)

    Cristina Dumitrescu

    2012-10-01

    Full Text Available Human health risk assessment of contaminated soils with carcinogenic pollutants is a multidisciplinary and participative procedure. For this reason, the opportunities of involving the beneficiaries and theentire community in considering human health for environmental assessment have to be improved. The present paper shows how to use the risk assessment as a method for investigation and evaluation of contaminated soils. The case study used to illustrate the functionality of the risk assessment model is related to an areacontaminated mainly with heavy metals. The area is located in CentralRomania, close to a specific pollution source–non-ferrous industry.Twenty four soil samples tak en from two depth layers of: 0–0.2 m,respectively 0.2-0.4 m from an area of 4.000 m2 were analyzed.Results of the chemical analysis indicated relatively high concentrations of As, Be, Cd, Cr VI, and Pb, which is matching with the existing pollution levels. Also, in the soil a pollution of organic nature, respectively contamination with polychlorinated biphenyls (PCBs was identified, its concentration exceeding the intervention threshold established by the Romanian regulation for sensitive uses. Results of the risk assessment revealed a risk factor of contaminated soils of 10-4, with two orders of magnitude above the acceptable risk of 10-6 suggested by the World Health Organization (WHO. Moreover, the contribution of the categories of pollutants(organic/inorganic to the estimated risk for each exposure pathwayconsidered was illustrated. Therefore, the paper, through the case study presented, represents an example of an approach that should be considered by the decision-making factors in approving cert ain projects, but also by environmental specialists when performing the health risk assessment in relation to certain objectives. This aspect is especially important as the experience of those performing the human health risk assessments at the planning stage of

  18. Chemical Reactivity Probes for Assessing Abiotic Natural Attenuation by Reducing Iron Minerals.

    Science.gov (United States)

    Fan, Dimin; Bradley, Miranda J; Hinkle, Adrian W; Johnson, Richard L; Tratnyek, Paul G

    2016-02-16

    Increasing recognition that abiotic natural attenuation (NA) of chlorinated solvents can be important has created demand for improved methods to characterize the redox properties of the aquifer materials that are responsible for abiotic NA. This study explores one promising approach: using chemical reactivity probes (CRPs) to characterize the thermodynamic and kinetic aspects of contaminant reduction by reducing iron minerals. Assays of thermodynamic CRPs were developed to determine the reduction potentials (ECRP) of suspended minerals by spectrophotometric determination of equilibrium CRP speciation and calculations using the Nernst equation. ECRP varied as expected with mineral type, mineral loading, and Fe(II) concentration. Comparison of ECRP with reduction potentials measured potentiometrically using a Pt electrode (EPt) showed that ECRP was 100-150 mV more negative than EPt. When EPt was measured with small additions of CRPs, the systematic difference between EPt and ECRP was eliminated, suggesting that these CRPs are effective mediators of electron transfer between mineral and electrode surfaces. Model contaminants (4-chloronitrobenzene, 2-chloroacetophenone, and carbon tetrachloride) were used as kinetic CRPs. The reduction rate constants of kinetic CRPs correlated well with the ECRP for mineral suspensions. Using the rate constants compiled from literature for contaminants and relative mineral reduction potentials based on ECRP measurements, qualitatively consistent trends were obtained, suggesting that CRP-based assays may be useful for estimating abiotic NA rates of contaminants in groundwater. PMID:26814150

  19. Assessing the correlation between anaerobic toluene degradation activity and bssA concentrations in hydrocarbon-contaminated aquifer material.

    Science.gov (United States)

    Kazy, Sufia K; Monier, Amy L; Alvarez, Pedro J J

    2010-09-01

    The assessment of biodegradation activity in contaminated aquifers is critical to demonstrate the performance of bioremediation and natural attenuation and to parameterize models of contaminant plume dynamics. Real time quantitative PCR (qPCR) was used to target the catabolic bssA gene (coding for benzylsuccinate synthase) and a 16S rDNA phylogenetic gene (for total Bacteria) as potential biomarkers to infer on anaerobic toluene degradation rates. A significant correlation (P = 0.0003) was found over a wide range of initial toluene concentrations (1-100 mg/l) between toluene degradation rates and bssA concentrations in anaerobic microcosms prepared with aquifer material from a hydrocarbon contaminated site. In contrast, the correlation between toluene degradation activity and total Bacteria concentrations was not significant (P = 0.1125). This suggests that qPCR targeting of functional genes might offer a simple approach to estimate in situ biodegradation activity, which would enhance site investigation and modeling of natural attenuation at hydrocarbon-contaminated sites. PMID:20204467

  20. Regional risk assessment of environmental contamination from oil pipelines

    International Nuclear Information System (INIS)

    This paper presents a methodology for assessing the risk of environmental contamination from oil pipeline leaks due to earthquakes. Risk is measured both as volume of oil released and remediation cost. The methodology was developed for use on a regional scale and thus relies on a limited amount of input data. Monte Carlo techniques are used to simulate earthquake events, while a deterministic model is used to estimate the volume of oil released at a particular site. A library of cost models is used to estimate the contamination and resulting remediation cost based on the volume of oil released and the general site conditions. This methodology has been implemented in a computer program, OILOSS, and the results are presented as annual frequency of exceedence curves for volume of oil released and cost of remediation

  1. Natural attenuation in contaminated soils with hydrocarbons; Atenuacion natural en suelos contaminados con hidrocarburos

    Energy Technology Data Exchange (ETDEWEB)

    Corona Ramirez, L.; Iturbide Arguelles, R. [Facultad de Ingenieria, UNAM, Mexico, D.F. (Mexico)

    2005-06-01

    A contaminated soil experiment was performed using simples from a refinery, containing oil derivative hydrocarbons, specifically those with high concentrations of polyaromathic hydrocarbons (PAH). The testing consisted in 7 pans with 7 kg of soil, the preparation of 6 pans under specific conditions and one as a blank, the conditions were: water content (15 y 30%), addition a non-ionic surfactant. The process consisted in the daily aeration and water control of the samples. The PAH were analyzed: anthracene, benzo(a) pyrene, chrysene, phenanthrene and naphthalene. The results after 8 weeks showed a gradual degradation of PAH, indicating a better removal obtained when the water content was 30% with nutrients addition. [Spanish] Se realizo un experimento con suelo contaminado proveniente de una refineria, el cual contaba con hidrocarburos derivados de petroleo, especificamente con concentraciones elevadas de hidrocarburos poliaromaticos (HAP). El estudio consistio en preparar 7 cajones con 7 kg de suelo, cada uno con las siguientes condiciones: S1suelo contaminado con hidrocarburos y 15% de contenido de agua. S2 suelo contaminado con hidrocarburo y adicion de Nitrogeno y Fosforo (N y P) con 15% de contenido de agua. S3 suelo contaminado con hidrocarburo y adicion de N y P mas un surfactante no ionico, Emulgin W600, con 15% de contenido de agua. S4 igual a S1 pero con 30% de contenido de agua. S5 igual a S2, con 30% de contenido de agua. S6 igual S3 con 30% de contenido de agua. S7 suelo contaminado testigo, sin control de humedad y sin aireacion. La experimentacion consistio en airear el suelo diariamente y controlar el contenido de agua de manera que este fuera constante. Los resultados, indican que la mejor remocion se obtuvo para el contenido de agua de 30%, con adicion de nutrientes y surfactante. Los compuestos con mayor eficiencia de remocion para todas las opciones son naftaleno y antraceno. Por lo tanto, de acuerdo con los resultados, los compuestos

  2. Bioremediation of petroleum hydrocarbons in contaminated soils: comparison of biosolids addition, carbon supplementation, and monitored natural attenuation

    International Nuclear Information System (INIS)

    Two methods of biostimulation were compared in a laboratory incubation study with monitored natural attenuation (MNA) for total petroleum hydrocarbon (TPH) degradation in diesel-contaminated Tarpley clay soil with low carbon content. One method utilized rapid-release inorganic fertilizers rich in N and P, and the other used sterilized, slow-release biosolids, which added C in addition to N and P. After 8 weeks of incubation, both biostimulation methods degraded approximately 96% of TPH compared to MNA, which degraded 93.8%. However, in the first week of incubation, biosolids-amended soils showed a linear two orders of magnitude increase in microbial population compared to MNA, whereas, in the fertilizer-amended soils, only a one order of magnitude increase was noted. In the following weeks, microbial population in the fertilizer-amended soils dropped appreciably, suggesting a toxic effect owing to fertilizer-induced acidity and/or NH3 overdosing. Results suggest that biosolids addition is a more effective soil amendment method for biostimulation than the commonly practiced inorganic fertilizer application, because of the abilities of biosolids to supplement carbon. No statistically significant difference was observed between the biostimulation methods and MNA, suggesting that MNA can be a viable remediation strategy in certain soils with high native microbial population. - Addition of biosolids is a potentially effective method of biostimulation for degradation of petroleum hydrocarbons in soils

  3. Natural attenuation in a slag heap contaminated with cadmium: The role of plants and arbuscular mycorrhizal fungi

    International Nuclear Information System (INIS)

    A field study of the natural attenuation occurring in a slag heap contaminated with high available cadmium was carried out. The aims of this research were: to determine plants colonizing this slag heap; to analyze colonization and morphological biodiversity of spores of arbuscular mycorrhizal fungi (AMF); to determine spore distribution in undisturbed samples; to know mycelium and glomalin abundance in the rhizosphere of these plants, and to investigate glomalin participation in Cd-stabilization. Forming vegetal islands, 22 different pioneering plant species from 11 families were colonizing the slag heap. The most common plants were species of Fabaceae, Asteraceae and Poaceae. Almost all plants were hosting AMF in their roots, and spores belonging to Gigaspora, Glomus, Scutellospora and Acaulospora species were observed. Micromorphological analysis showed that spores were related to decomposing vegetal residues and excrements, which means that mesofauna is contributing to their dispersion in the groundmass. Mycelium mass ranged from 0.11 to 26.3 mg/g, which contained between 13 and 75 mg of glomalin/g. Slag-extracted total glomalin was between 0.36 and 4.74 mg/g. Cadmium sequestered by glomalin extracted from either slag or mycelium was 0.028 mg/g. The ecological implication of these results is that organisms occupying vegetal patches are modifying mine residues, which contribute to soil formation

  4. A chronic plant test for the assessment of contaminated soils. Part 2. Testing of contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Junker, T.; Roembke, J. [ECT Oekotoxikologie GmbH, Floersheim (Germany); Kalsch, W.

    2006-06-15

    Background and scope. A new chronic plant test system which is based on experiences with various acute plant tests (e.g. published by OECD or ISO) and existing north American plant-life-cycle bioassays was standardised in a project sponsored by the German government. Characteristic properties of the test system, which can be performed either with Brassica rapa (turnip rape) or Avena sativa (oat), are described in part 1 of this mini-series. Methods. This new test was used to assess the effects of natural soil samples contaminated with TNT (2,4,6-Trinitrotoluene) or PAHs (poly-aromatic hydrocarbons). The soils were tested after taken from the field as well as after being remediated. Different control and reference soils were used to evaluate the test results. In addition, they were compared with the results of tests in which either TNT or Pyrene were spiked to field and standard soils (see part 1 of this mini-series). Results. All contaminated soils showed clear effects in the chronic plant test (usually B. rapa was more sensitive than A. sativa). LUFA 2.2 standard soil and OECD artificial soil are well-suited as control and mixture substrates, while reference soils collected at uncontaminated sites were several times as phytotoxic. In most of the latter cases, soil properties could be identified as the main cause of these effects (e.g. the pH value). While the sensitivity of the reproduction and biomass endpoints did not differ much in general, it is recommended to measure different endpoints (i.e. biomass and reproduction) due to the different mode-of-action of contaminants. In the case of TNT, a good agreement between the results of single chemical tests and tests with TNT-contaminated soils was found (due to the minimal effects of Pyrene, the same statement is not possible for PAHs). (orig.)

  5. The uses of bioindicators in radionuclide contamination assessment

    International Nuclear Information System (INIS)

    This paper is a brief review and discussion of some approaches to sampling using bioindicators that have been employed in the assessment of radionuclide contamination in Ireland. Studies by other researchers are also referred to and the fields of research in radioecology where the use of bioindicators could be further developed are discussed. The review includes a discussion of the important attributes of bioindicators and how they can best be used in the development of effective but economical sampling strategies that yield the maximum amount of information. (author)

  6. Ecological risk assessment of a site contaminated with petroleum hydrocarbons

    International Nuclear Information System (INIS)

    The aquatic and terrestrial health risks associated with petroleum contamination on a decommissioned military base, contaminated with products ranging from Bunker C oil to aviation fuel, were assessed using a methodology whereby an analytical measurement of total petroleum hydrocarbons (TPH) could be correlated with compositional characterization and thus with toxicity. The constituents of petroleum hydrocarbon contamination represent wide ranges of physical-chemical properties, environmental fate, and toxicity. The composition of TPH can vary greatly, dependent on the sources or fuel types and the interaction of age as well as site- and chemical-specific characteristics in determining the impact of weathering processes. Therefore, a bulk sum analysis of TPH cannot be related to toxicity without characterization of its composition and association of the constituents, and therefore composition, with actual toxicity data. To address this need, the constituents of TPH were represented by surrogate chemicals, with selection based on structure-activity relationships and available toxicity data. Toxicological profiles were developed from governmental regulations and on the published literature for both the aquatic and terrestrial media. Risk characterization consisted of a comparison of water concentration limits and exposure limits, developed for each surrogate, to estimated surrogate concentrations throughout the site. The concentrations of surrogates were extrapolated from TPH composition characterization analyses, conducted at a select number of sampling locations, to bulk sum analyses of TPH at related sampling locations

  7. Inorganic contaminants attenuation in acid mine drainage by fly ash and fly ash-ordinary Portland cement (OPC) blends : column experiments

    International Nuclear Information System (INIS)

    The infiltration of acid mine drainage (AMD) material into mine voids is one of the environmental impacts of underground coal mining. In this study, the mitigation of AMD in a mine void was simulated in laboratory conditions. Various mixtures of fly ash, solid residues, and Portland cement were added to packed columns over a 6-month period. The fly ash additions generated near-neutral to alkaline pH levels, which in turn induced precipitation, co-precipitation, and adsorption contaminant attenuation mechanisms. A modelling study demonstrated that the precipitation of ferrihydrite, Al-hydroxides, Al-oxyhydroxysulphates, gypsum, ettringite, manganite, and rhodochrosite lowered contaminant levels. Results of the study indicated that the pH regime and acidity level of the AMD strongly influenced both the leaching of the toxic trace elements as well as the attenuation of the AMD. 3 refs., 2 figs.

  8. Contamination

    OpenAIRE

    Cundill, A.; J. Bacon; Dale, P; Fordyce, F.M.; Fowler, D; Hedmark, A.; Hern, A.; Skiba, U.

    2011-01-01

    Soil contamination occurs when substances are added to soil, resulting in increases in concentrations above background or reference levels. Pollution may follow from contamination when contaminants are present in amounts that are detrimental to soil quality and become harmful to the environment or human health. Contamination can occur via a range of pathways including direct application to land and indirect application from atmospheric deposition. Contamination was identified b...

  9. Reliability of computed tomography measurements in assessment of thigh muscle cross-sectional area and attenuation

    International Nuclear Information System (INIS)

    Advancement in technology of computer tomography (CT) and introduction of new medical imaging softwares enables easy and rapid assessment of muscle cross-sectional area (CSA) and attenuation. Before using these techniques in clinical studies there is a need for evaluation of the reliability of the measurements. The purpose of the study was to evaluate the inter- and intra-observer reliability of ImageJ in measuring thigh muscles CSA and attenuation in patients with anterior cruciate ligament (ACL) injury by computer tomography. 31 patients from an ongoing study of rehabilitation and muscle atrophy after ACL reconstruction were included in the study. Axial CT images with slice thickness of 10 mm at the level of 150 mm above the knee joint were analyzed by two investigators independently at two times with a minimum of 3 weeks between the two readings using NIH ImageJ. CSA and the mean attenuation of individual thigh muscles were analyzed for both legs. Mean CSA and mean attenuation values were in good agreement both when comparing the two observers and the two replicates. The inter- and intraclass correlation (ICC) was generally very high with values from 0.98 to 1.00 for all comparisons except for the area of semimembranosus. All the ICC values were significant (p < 0,001). Pearson correlation coefficients were also generally very high with values from 0.98 to 1.00 for all comparisons except for the area of semimembranosus (0.95 for intraobserver and 0.92 for interobserver). This study has presented ImageJ as a method to monitor and evaluate CSA and attenuation of different muscles in the thigh using CT-imaging. The method shows an overall excellent reliability with respect to both observer and replicate

  10. Assessment of in situ biodegradation of monochlorobenzene in contaminated groundwater treated in a constructed wetland

    International Nuclear Information System (INIS)

    The degradation of monochlorobenzene (MCB) was assessed in a constructed wetland treating MCB contaminated groundwater using a detailed geochemical characterisation, stable isotope composition analysis and in situ microcosm experiments. A correlation between ferrous iron mobilisation, decreasing MCB concentration and enrichment in carbon isotope composition was visible at increasing distance from the inflow point, indicating biodegradation of MCB in the wetland. Additionally, in situ microcosm systems loaded with 13C-labelled MCB were deployed for the first time in sediments to investigate the biotransformation of MCB. Incorporation of 13C-labelled carbon derived from the MCB into bacterial fatty acids substantiated in situ degradation of MCB. The detection of 13C-labelled benzene indicated reductive dehalogenation of MCB. This integrated approach indicated the natural attenuation of the MCB in a wetland system. Further investigations are required to document and optimise the in situ biodegradation of MCB in constructed and natural wetland systems treating contaminated groundwater. - An integrated approach including isotope composition analysis and in situ microcosm experiments provided evidences for in situ biodegradation of MCB in a wetland system

  11. Assessment of in situ biodegradation of monochlorobenzene in contaminated groundwater treated in a constructed wetland

    Energy Technology Data Exchange (ETDEWEB)

    Braeckevelt, Mareike [Departments of Bioremediation, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, Leipzig D-04318, Saxonia (Germany); Rokadia, Hemal [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, Leipzig D-04318, Saxonia (Germany); Imfeld, Gwenael [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, Leipzig D-04318, Saxonia (Germany)]. E-mail: gwenael.imfeld@ufz.de; Stelzer, Nicole [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, Leipzig D-04318, Saxonia (Germany); Paschke, Heidrun [Department of Analytical Chemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, Leipzig D-04318, Saxonia (Germany); Kuschk, Peter [Departments of Bioremediation, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, Leipzig D-04318, Saxonia (Germany); Kaestner, Matthias [Departments of Bioremediation, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, Leipzig D-04318, Saxonia (Germany); Richnow, Hans-H. [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, Leipzig D-04318, Saxonia (Germany); Weber, Stefanie [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, Leipzig D-04318, Saxonia (Germany)

    2007-07-15

    The degradation of monochlorobenzene (MCB) was assessed in a constructed wetland treating MCB contaminated groundwater using a detailed geochemical characterisation, stable isotope composition analysis and in situ microcosm experiments. A correlation between ferrous iron mobilisation, decreasing MCB concentration and enrichment in carbon isotope composition was visible at increasing distance from the inflow point, indicating biodegradation of MCB in the wetland. Additionally, in situ microcosm systems loaded with {sup 13}C-labelled MCB were deployed for the first time in sediments to investigate the biotransformation of MCB. Incorporation of {sup 13}C-labelled carbon derived from the MCB into bacterial fatty acids substantiated in situ degradation of MCB. The detection of {sup 13}C-labelled benzene indicated reductive dehalogenation of MCB. This integrated approach indicated the natural attenuation of the MCB in a wetland system. Further investigations are required to document and optimise the in situ biodegradation of MCB in constructed and natural wetland systems treating contaminated groundwater. - An integrated approach including isotope composition analysis and in situ microcosm experiments provided evidences for in situ biodegradation of MCB in a wetland system.

  12. Comparative bioremediation of heavy metals and petroleum hydrocarbons co-contaminated soil by natural attenuation, phytoremediation, bioaugmentation and bioaugmentation-assisted phytoremediation.

    Science.gov (United States)

    Agnello, A C; Bagard, M; van Hullebusch, E D; Esposito, G; Huguenot, D

    2016-09-01

    Biological remediation technologies are an environmentally friendly approach for the treatment of polluted soils. This study evaluated through a pot experiment four bioremediation strategies: a) natural attenuation, b) phytoremediation with alfalfa (Medicago sativa L.), c) bioaugmentation with Pseudomonas aeruginosa and d) bioaugmentation-assisted phytoremediation, for the treatment of a co-contaminated soil presenting moderate levels of heavy metals (Cu, Pb and Zn at 87, 100 and 110mgkg(-1) DW, respectively) and petroleum hydrocarbons (3800mgkg(-1) DW). As demonstrated by plant biomass and selected physiological parameters alfalfa plants were able to tolerate and grow in the co-contaminated soil, especially when soil was inoculated with P. aeruginosa, which promoted plant growth (56% and 105% increase for shoots and roots, respectively) and appeared to alleviate plant stress. The content of heavy metals in alfalfa plants was limited and followed the order: Zn>Cu>Pb. Heavy metals were mainly concentrated in plant roots and were poorly translocated, favouring their stabilization in the root zone. Bioaugmentation of planted soil with P. aeruginosa generally led to a decrease of plant metal concentration and translocation. The highest degree of total petroleum hydrocarbon removal was obtained for bioaugmentation-assisted phytoremediation treatment (68%), followed by bioaugmentation (59%), phytoremediation (47%) and natural attenuation (37%). The results of this study demonstrated that the combined use of plant and bacteria was the most advantageous option for the treatment of the present co-contaminated soil, as compared to natural attenuation, bioaugmentation or phytoremediation applied alone. PMID:26524994

  13. Updating computed tomography of bladder carcinoma in assessing response to immunotherapy and attenuated irradiation

    International Nuclear Information System (INIS)

    Computed tomography was utilized as part of the surgical-pathological-radiological evaluation of 21 patients who were treated for bladder carcinoma with attenuated irradiation and immunotherapy. Fifteen patients had moderately infiltrative (Stage Tsub(2a-b) or less) disease and it was found that a routine high resolution CT technique using a modern fast scanner delineated the tumor in most cases. More accurate assessment of tumor response to therapy and evaluation of tumor progression was facilitated using a gas insufflation technique combined with intravenous contrast infusion. This was followed in selected cases by quantitative measurements of CT attenuation values using a recently introduced CT software program. Using this program, individual pixel values were obtained in selected areas and evaluation of the resulting numerical data and pixel histograms aided in the differentiation of tumor tissue from adjacent bladder wall and mapped out areas of tumor necrosis. Our preliminary observations suggest that quantitative CT studies incorporating assessment of printouts of attenuation values of adjacent pixels within a region of interest will improve the delineation of smaller (Tsub(2a)/Tsub(2b)) lesions and will aid objective characterization of tumor tissue during and following therapy. (orig.)

  14. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site in Lakeview, Oregon

    International Nuclear Information System (INIS)

    This Baseline Risk Assessment of Ground Water Contamination at the Uranium Mill Tailings Site in Lake view, Oregon evaluates potential impacts to public health or the environment resulting from ground water contamination at the former uranium mill processing site

  15. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site in Lakeview, Oregon

    Energy Technology Data Exchange (ETDEWEB)

    1994-10-01

    This Baseline Risk Assessment of Ground Water Contamination at the Uranium Mill Tailings Site in Lake view, Oregon evaluates potential impacts to public health or the environment resulting from ground water contamination at the former uranium mill processing site.

  16. MRI-guided attenuation correction in whole-body PET/MR : assessment of the effect of bone attenuation

    NARCIS (Netherlands)

    Akbarzadeh, A.; Ay, M. R.; Ahmadian, A.; Alam, N. Riahi; Zaidi, H.

    2013-01-01

    Hybrid PET/MRI presents many advantages in comparison with its counterpart PET/CT in terms of improved soft-tissue contrast, decrease in radiation exposure, and truly simultaneous and multi-parametric imaging capabilities. However, the lack of well-established methodology for MR-based attenuation co

  17. Application of a contaminant mass balance method at an old landfill to assess the impact on water resources.

    Science.gov (United States)

    Thomsen, Nanna I; Milosevic, Nemanja; Bjerg, Poul L

    2012-12-01

    Old and unlined landfill sites pose a risk to groundwater and surface water resources. While landfill leachate plumes in sandy aquifers have been studied, landfills in clay till settings and their impact on receiving water bodies are not well understood. In addition, methods for quantitatively linking soil and groundwater contamination to surface water pollution are required. This paper presents a method which provides an estimate of the contaminant mass discharge, using a combination of a historical investigation and contaminant mass balance approach. The method works at the screening level and could be part of a risk assessment. The study site was Risby Landfill, an old unlined landfill located in a clay till setting on central Zealand, Denmark. The contaminant mass discharge was determined for three common leachate indicators: chloride, dissolved organic carbon and ammonium. For instance, the mass discharge of chloride from the landfill was 9.4 ton/year and the mass discharge of chloride to the deep limestone aquifer was 1.4 ton/year. This resulted in elevated concentrations of leachate indicators (chloride, dissolved organic carbon and ammonium) in the groundwater. The mass discharge of chloride to the small Risby Stream down gradient of the landfill was approximately 31 kg/year. The contaminant mass balance method worked well for chloride and dissolved organic carbon, but the uncertainties were elevated for ammonium due to substantial spatial variability in the source composition and attenuation processes in the underlying clay till. PMID:22868040

  18. Assessment of produced water contaminated soils to determine remediation requirements

    International Nuclear Information System (INIS)

    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

  19. Quantitative assessment of historical coastal landfill contamination using in-situ field portable XRF (FPXRF)

    Science.gov (United States)

    O'Shea, Francis; Spencer, Kate; Brasington, James

    2014-05-01

    Historically, waste was deposited on low value, easily accessible coastal land (e.g. marsh land). Within England and Wales alone, there are over 5000 historical landfills situated within coastal areas at risk of flooding at a 1 in 100 year return period (Environment Agency, 2012). Historical sites were constructed prior to relevant legislation, and have no basal or side wall engineering, and the waste constituents are mostly unknown. In theory, contaminant concentrations should be reduced through natural attenuation as the leachate plume migrates through surrounding fine-grained inter-tidal sediments before reaching receptor waters. However, erosion resulting from rising sea level and increased storm intensity may re-distribute these sediments and release associated contaminants into the estuarine and coastal environment. The diffuse discharge from these sites has not been quantified and this presents a problem for those landfill managers who are required to complete EIAs. An earlier detailed field campaign at Newlands landfill site, on the Thames Estuary, UK identified a sub-surface (~2m depth) contaminant plume extending c. 20 m from the landfill boundary into surrounding fine-grained saltmarsh sediments. These saltmarsh sediments are risk of being eroded releasing their contaminant load to the Thames Estuary. The aims of this work were to; 1) assess whether this plume is representative of other historical landfills with similar characteristics and 2) to develop a rapid screening methodology using field portable XRF that could be used to identify potential risk of other coastal landfill sites. GIS was used to select landfill sites of similar age, hydrological regime and sedimentary setting in the UK, for comparison. Collection of sediment samples and analysis by ICP OES is expensive and time-consuming, therefore cores were extracted and analysed with a Niton Goldd XRF in-situ. Contaminant data were available immediately and the sampling strategy could be adapted

  20. The attenuation of concentrations model: a new method for assessing mercury mobility in sediments

    Directory of Open Access Journals (Sweden)

    Julio C. Wasserman

    2004-02-01

    Full Text Available In this work we propose a new approach for the determination of the mobility of mercury in sediments based on spatial distribution of concentrations. We chose the Tainheiros Cove, located in the Todos os Santos Bay, Brazil, as the study area, for it has a history of mercury contamination due to a chloro-alkali plant that was active during 12 years. Twenty-six surface sediment samples were collected from the area and mercury concentrations were measured by cold vapour atomic absorption spectrophotometry. A contour map was constructed from the results, indicating that mercury accumulated in a "hot spot" where concentrations reach more than 1 µg g-1. The model is able to estimate mobility of mercury in the sediments based on the distances between iso-concentration contours that determines an attenuation of concentrations factor. Values of attenuation ranged between 0.0729 (East of the hot spot, indicating higher mobility to 0.7727 (North of the hot spot, indicating lower mobility.

  1. Assessment of endothelial function and myocardial flow reserve using {sup 15}O-water PET without attenuation correction

    Energy Technology Data Exchange (ETDEWEB)

    Tuffier, Stephane; Joubert, Michael; Bailliez, Alban [EA 4650, Normandie Universite, Caen (France); Legallois, Damien [EA 4650, Normandie Universite, Caen (France); Caen University Hospital, Department of Cardiology, Caen (France); Belin, Annette [Caen University Hospital, Department of Cardiac Surgery, Caen (France); Redonnet, Michel [Rouen University Hospital, Department of Cardiac Surgery, Rouen (France); Agostini, Denis [EA 4650, Normandie Universite, Caen (France); Caen University Hospital, Department of Nuclear Medicine, Caen (France); Manrique, Alain [EA 4650, Normandie Universite, Caen (France); Caen University Hospital, Department of Nuclear Medicine, Caen (France); Cyceron PET Centre, Caen (France)

    2016-02-15

    Myocardial blood flow (MBF) measurement using positron emission tomography (PET) from the washout rate of {sup 15}O-water is theoretically independent of tissue attenuation. The aim of this study was to evaluate the impact of not using attenuation correction in the assessment of coronary endothelial function and myocardial flow reserve (MFR) using {sup 15}O-water PET. We retrospectively processed 70 consecutive {sup 15}O-water PET examinations obtained at rest and during cold pressor testing (CPT) in patients with dilated cardiomyopathy (n = 58), or at rest and during adenosine infusion in heart transplant recipients (n = 12). Data were reconstructed with attenuation correction (AC) and without attenuation correction (NAC) using filtered backprojection, and MBF was quantified using a single compartmental model. The agreement between AC and NAC data was assessed using Lin's concordance correlation coefficient followed by Bland-Altman plot analysis. Regarding endothelial function, NAC PET showed poor reproducibility and poor agreement with AC PET data. Conversely, NAC PET demonstrated high reproducibility and a strong agreement with AC PET for the assessment of MFR. Non-attenuation-corrected {sup 15}O-water PET provided an accurate measurement of MFR compared to attenuation-corrected PET. However, non-attenuation-corrected PET data were less effective for the assessment of endothelial function using CPT in this population. (orig.)

  2. Assessment of endothelial function and myocardial flow reserve using 15O-water PET without attenuation correction

    International Nuclear Information System (INIS)

    Myocardial blood flow (MBF) measurement using positron emission tomography (PET) from the washout rate of 15O-water is theoretically independent of tissue attenuation. The aim of this study was to evaluate the impact of not using attenuation correction in the assessment of coronary endothelial function and myocardial flow reserve (MFR) using 15O-water PET. We retrospectively processed 70 consecutive 15O-water PET examinations obtained at rest and during cold pressor testing (CPT) in patients with dilated cardiomyopathy (n = 58), or at rest and during adenosine infusion in heart transplant recipients (n = 12). Data were reconstructed with attenuation correction (AC) and without attenuation correction (NAC) using filtered backprojection, and MBF was quantified using a single compartmental model. The agreement between AC and NAC data was assessed using Lin's concordance correlation coefficient followed by Bland-Altman plot analysis. Regarding endothelial function, NAC PET showed poor reproducibility and poor agreement with AC PET data. Conversely, NAC PET demonstrated high reproducibility and a strong agreement with AC PET for the assessment of MFR. Non-attenuation-corrected 15O-water PET provided an accurate measurement of MFR compared to attenuation-corrected PET. However, non-attenuation-corrected PET data were less effective for the assessment of endothelial function using CPT in this population. (orig.)

  3. Chemometric assessment of enhanced bioremediation of oil contaminated soils.

    Science.gov (United States)

    Soleimani, Mohsen; Farhoudi, Majid; Christensen, Jan H

    2013-06-15

    Bioremediation is a promising technique for reclamation of oil polluted soils. In this study, six methods for enhancing bioremediation were tested on oil contaminated soils from three refinery areas in Iran (Isfahan, Arak, and Tehran). The methods included bacterial enrichment, planting, and addition of nitrogen and phosphorous, molasses, hydrogen peroxide, and a surfactant (Tween 80). Total petroleum hydrocarbon (TPH) concentrations and CHEMometric analysis of Selected Ion Chromatograms (SIC) termed CHEMSIC method of petroleum biomarkers including terpanes, regular, diaromatic and triaromatic steranes were used for determining the level and type of hydrocarbon contamination. The same methods were used to study oil weathering of 2 to 6 ring polycyclic aromatic compounds (PACs). Results demonstrated that bacterial enrichment and addition of nutrients were most efficient with 50% to 62% removal of TPH. Furthermore, the CHEMSIC results demonstrated that the bacterial enrichment was more efficient in degradation of n-alkanes and low molecular weight PACs as well as alkylated PACs (e.g. C₃-C₄ naphthalenes, C₂ phenanthrenes and C₂-C₃ dibenzothiophenes), while nutrient addition led to a larger relative removal of isoprenoids (e.g. norpristane, pristane and phytane). It is concluded that the CHEMSIC method is a valuable tool for assessing bioremediation efficiency. PMID:23644688

  4. Assessment of atmospheric microbial contamination in a mobile dental unit

    Directory of Open Access Journals (Sweden)

    Shivakumar K

    2007-01-01

    Full Text Available Introduction: Bioaerosols are important considerations in infection control as well as in occupational health. Bioaerosols may carry potentially hazardous microbes, viruses, fungi, allergens, and other toxic substances that may harm the dental operator, patient, and the dental assistant by causing nosocomial infections. Objective: To assess the level of atmospheric microbial contamination before, during, and after dental treatment procedures in the dental operatory of a mobile dental unit (MDU. Materials and Methods: The study included three treatment sessions on different working days, with an interval of one month. The MDU was fumigated before the start of the study. Brain Heart Infusion Agar with 5% sheep blood was used to collect the gravitometric settling of aerosols produced before, during, and after dental treatment procedures. The agar plates were sent for aerobic and anaerobic culture. Results: The results showed that atmospheric microbial contamination (CFUs/plate was 4 times higher during working sessions as compared to the levels before the working sessions. At the end of the working day, aerosols decreased by almost 3 times that seen during work. Conclusion: The aerosols increased during and after work sessions. This shows the increased risk of transmission of infectious agents to the dentists who work in the MDU. Hence, all necessary preventive measures should be advised and need to be followed strictly.

  5. Problems of the assessment of contaminated mining sites

    Energy Technology Data Exchange (ETDEWEB)

    Wichterey, K.; Gehrcke, K.; Kuemmel, M. [Bundesamt fuer Strahlenschutz, Berlin (Germany)

    1999-12-01

    In Germany there are numerous relics of former mining activities with enhanced levels of radionuclides of the uranium/radium series. Of special importance are the relics of uranium and other non-ferrous ore mining in the three Federal States of Saxony, Thuringia and Saxony-Anhalt. The majority of these relics is situated in densely populated areas. This gives rise to the question whether measures have to be taken to protect the population from detrimental health impacts. Public concern often concentrates on radioactivity. Health impacts may, however, originate from chemically hazardous substances, too. Such substances like, for instance, arsenic, often accompany radioactive contamination in mining relics. Also, mining safety, landscape conservation and other aspects may play a significant role in the decision-making process, especially for large and complex mining sites. This is, however, outside the scope of the present paper, which is confined to the discussion of problems associated with the assessment of mining sites contaminated with both enhanced levels of naturally occurring radionuclides and chemically toxic/carcinogenic substances. Sites with mixed contaminants like mining relics may cause special problems in the assessment of hazards to human health. Different scientific approaches and historic developments led to considerable differences in existing regulations. Both, on the national and international scale efforts are made towards a harmonization. Having reviewed studies carried out in Germany we arrived at the conclusion that generation of a common risk scale for all kinds of hazards seems to be a too challenging problem to be solved within a foreseeable time scale. It is reasonable, at least in principle, to define a unified metric for carcinogenic effects of ionizing radiation and harmful chemicals. Even this needs a lot of research work as a basis for adaptations in the legal systems. What seems to be reasonable and in our opinion is much more

  6. Problems of the assessment of contaminated mining sites

    International Nuclear Information System (INIS)

    In Germany there are numerous relics of former mining activities with enhanced levels of radionuclides of the uranium/radium series. Of special importance are the relics of uranium and other non-ferrous ore mining in the three Federal States of Saxony, Thuringia and Saxony-Anhalt. The majority of these relics is situated in densely populated areas. This gives rise to the question whether measures have to be taken to protect the population from detrimental health impacts. Public concern often concentrates on radioactivity. Health impacts may, however, originate from chemically hazardous substances, too. Such substances like, for instance, arsenic, often accompany radioactive contamination in mining relics. Also, mining safety, landscape conservation and other aspects may play a significant role in the decision-making process, especially for large and complex mining sites. This is, however, outside the scope of the present paper, which is confined to the discussion of problems associated with the assessment of mining sites contaminated with both enhanced levels of naturally occurring radionuclides and chemically toxic/carcinogenic substances. Sites with mixed contaminants like mining relics may cause special problems in the assessment of hazards to human health. Different scientific approaches and historic developments led to considerable differences in existing regulations. Both, on the national and international scale efforts are made towards a harmonization. Having reviewed studies carried out in Germany we arrived at the conclusion that generation of a common risk scale for all kinds of hazards seems to be a too challenging problem to be solved within a foreseeable time scale. It is reasonable, at least in principle, to define a unified metric for carcinogenic effects of ionizing radiation and harmful chemicals. Even this needs a lot of research work as a basis for adaptations in the legal systems. What seems to be reasonable and in our opinion is much more

  7. Extraction procedure compared to attenuation model to assess heavy metals mobility in sediments from Sepetiba Bay, Rio de Janeiro

    International Nuclear Information System (INIS)

    Sepetiba bay, located about 60 km west of the metropolitan region of Rio de Janeiro city, has undergone notable development in the last decades, with the establishment of about 400 industrial plants in its basin, basically metallurgical, which release its industrial waste either straight into the bay or through local rivers. The Sepetiba harbor also brought up a lot of industrial investment in that area. This urban and industrial expansion caused several environmental impacts, mainly due to the presence of heavy metals and other potentially toxic substances present in the effluents discharged into the bay. This work aimed to assess heavy metal (Cd, Cu, Ni, Pb e Zn) contamination and mobility in sediments from Sepetiba bay. The acid-volatile sulfides (AVS) and the concentration of simultaneously extracted metals (SIGMA[SEM) were determined in 65 sediment samples from Sepetiba bay, representing the whole area. The results obtained showed that Cd, Cu, Pb and Zn presented higher concentrations in the northeastern area (mainly in the mouth of Guandu and Canal de Sao Francisco rivers), while the highest concentration of Ni were observed in the western region of the bay. The comparison between SEM concentrations with the Canadian Sediment Quality Guidelines (TEL and PEL) indicated that Cd and Zn presented values which may hazard to aquatic organisms (concentration levels above PEL); the elements Cu, Pb and Ni presented concentration levels below PEL, suggesting low probability of toxicological effects to the aquatic organisms. On the other hand, the ratio Σ[SEM]/[AVS] was below 1 in the northeastern region, indicating that, in spite of the high concentration of the analyzed metals in this area, they are trapped in the sediment, as sulfides. The total metal concentrations in the sediments were also determined and the same distribution pattern obtained for the SEM were observed, with high concentrations in the northeastern region of the bay, classifying the area as level 2

  8. PBT assessment and prioritization of contaminants of emerging concern: Pharmaceuticals.

    Science.gov (United States)

    Sangion, Alessandro; Gramatica, Paola

    2016-05-01

    The strong and widespread use of pharmaceuticals, together with incorrect disposal procedures, has recently made these products contaminants of emerging concern (CEC). Unfortunately, little is known about pharmaceuticals' environmental behaviour and ecotoxicity, so that EMEA (European Medicines Agency) released guidelines for the pharmaceuticals' environmental risk assessment. In particular, there is a severe lack of information about persistence, bioaccumulation and toxicity (PBT) of the majority of the thousands of substances on the market. Computational tools, like QSAR (Quantitative Structure Activity Relationship) models, are the only way to screen large sets of chemicals in short time, with the aim of ranking, highlighting and prioritizing the most environmentally hazardous for focusing further experimental studies. In this work we propose a screening method to assess the potential persistence, bioaccumulation and toxicity of more than 1200 pharmaceutical ingredients, based on the application of two different QSAR models. We applied the Insubria-PBT Index, a MLR (Multiple Linear Regression) QSAR model based on four simple molecular descriptors, implemented in QSARINS software, and able to synthesize the PBT potential in a unique cumulative value and the US-EPA PBT Profiler that assesses the PBT behaviour evaluating separately P, B and T. Particular attention was given to the study of Applicability Domain in order to provide reliable predictions. An agreement of 86% was found between the two models and a priority list of 35 pharmaceuticals, highlighted as potential PBTs by consensus, was proposed for further experimental validation. Moreover, the results of this computational screening are in agreement with preliminary experimental data in the literature. This study shows how in silico models can be applied in the hazard assessment to perform preliminary screening and prioritization of chemicals, and how the identification of the structural features, mainly

  9. Assessment of natural attenuation of aromatic hydrocarbons in groundwater near a former manufactured-gas plant, South Carolina, USA

    Science.gov (United States)

    Landmeyer, J.E.; Chapelle, F.H.; Petkewich, M.D.; Bradley, P.M.

    1998-01-01

    Shallow, anaerobic groundwater near a former manufactured-gas plant (MGP) in Charleston, South Carolina, USA, contains mono- and polycyclic aromatic hydrocarbons (MAHs and PAHs, respectively). Between 1994 and 1997, a combination of field, laboratory, and numerical-flow and transport-model investigations were made to assess natural attenuation processes affecting MAH and PAH distributions. This assessment included determination of adsorption coefficients (K(ad)) and first-order biodegradation rate constants (K(bio)) using aquifer material from the MGP site and adjacent properties. Naphthalene adsorption (K(ad) = 1.35 x 10-7 m3/mg) to aquifer sediments was higher than toluene adsorption (K(ad) = 9.34 x 10-10 m3/mg), suggesting preferential toluene transport relative to naphthalene. However, toluene and benzene distributions measured in January 1994 were smaller than the naphthalene distribution. This scenario can be explained, in part, by the differences between biodegradation rates of the compounds. Aerobic first-order rate constants of 14C-toluene, 14C-benzene, and 14C-naphthalene degradation were similar (-0.84, -0.03, and 0.88 day-1, respectively), but anaerobic rate constants were higher for toluene and benzene (-0.002 and -0.00014 day-1, respectively) than for naphthalene (-0.000046 day-1). Both areal and cross-sectional numerical simulations were used to test the hypothesis suggested by these rate differences that MAH compounds will be contained relative to PAHs. Predictive simulations indicated that the distributions of toluene and benzene reach steady-state conditions before groundwater flow lines discharge to an adjacent surface-water body, but do discharge low concentrations of naphthalene. Numerical predictions were 'audited' by measuring concentrations of naphthalene, toluene, and benzene at the site in early 1997. Measured naphthalene and toluene concentrations were substantially reduced and the areal extent of contamination smaller than was both

  10. Molecular contamination assessments on Hinode X-ray telescope

    International Nuclear Information System (INIS)

    The Hinode (Solar-B) was launched by M-V rocket on 22 September 2006 UT. The telemetry data of the Hinode X-ray Telescope (XRT) showed that the X-ray count rate detected with the XRT had decreased rapidly since the operational heaters on the XRT telescope tube were turned on. This is attributed to the fact that molecular contaminants accumulated onto the CCD with the temperature of -60degC resulting in the degradation of the XRT sensitivity. We baked the CCD at the temperature of 35degC in order to remove the contaminants from the CCD surface. However many contaminant spots appeared on the surface. We found that major contaminant source existed in the telescope tube, and identified the contaminants as diethylhexyl phthalate (DEHP) or DEHP-like organics. The mechanisms to yield the contaminant spots were discussed. (author)

  11. Methods for assessing the environmental risks from the resistant pesticide contamination

    OpenAIRE

    T. Moklyachuk

    2014-01-01

    Methods of assessing environmental risk has been considered in order to identify and then apply an optimal recovery method of remediation of soils contaminated with persistent pesticides. Value of risk from contamination in two different models — the situational risk and CalTOX has been counted and compared. A mathematical model that describes a distribution of the site contamination by persistent pesticides depending on the distance from the depot, and gives an opportunity to assess the si...

  12. Toxicity Assessment of Contaminated Soils of Solid Domestic Waste Landfill

    International Nuclear Information System (INIS)

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

  13. Analysis And Assessment Of The Security Method Against Incidental Contamination In The Collective Water Supply System

    Directory of Open Access Journals (Sweden)

    Szpak Dawid

    2015-09-01

    Full Text Available The paper presents the main types of surface water incidental contaminations and the security method against incidental contamination in water sources. Analysis and assessment the collective water supply system (CWSS protection against incidental contamination was conducted. Failure Mode and Effects Analysis (FMEA was used. The FMEA method allow to use the product or process analysis, identification of weak points, and implementation the corrections and new solutions for eliminating the source of undesirable events. The developed methodology was shown in application case. It was found that the risk of water contamination in water-pipe network of the analyzed CWSS caused by water source incidental contamination is at controlled level.

  14. Baseline risk assessment of groundwater contamination at the Uranium Mill Tailings Site near Gunnison, Colorado

    International Nuclear Information System (INIS)

    This report evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy's (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells to determine the potential for immediate human health and environmental impacts. This risk assessment evaluates the most contaminated groundwater that flows beneath the processing site towards the Gunnison River. The monitor wells that have consistently shown the highest concentration of most contaminants are used in this risk assessment. This risk assessment will be used in conjunction with additional activities and documents to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the groundwater are cadmium, cobalt, iron, manganese, sulfate, uranium, and some of the products of radioactive decay of uranium

  15. Health Risk-Based Assessment and Management of Heavy Metals-Contaminated Soil Sites in Taiwan

    Directory of Open Access Journals (Sweden)

    Zueng-Sang Chen

    2010-10-01

    Full Text Available Risk-based assessment is a way to evaluate the potential hazards of contaminated sites and is based on considering linkages between pollution sources, pathways, and receptors. These linkages can be broken by source reduction, pathway management, and modifying exposure of the receptors. In Taiwan, the Soil and Groundwater Pollution Remediation Act (SGWPR Act uses one target regulation to evaluate the contamination status of soil and groundwater pollution. More than 600 sites contaminated with heavy metals (HMs have been remediated and the costs of this process are always high. Besides using soil remediation techniques to remove contaminants from these sites, the selection of possible remediation methods to obtain rapid risk reduction is permissible and of increasing interest. This paper discusses previous soil remediation techniques applied to different sites in Taiwan and also clarified the differences of risk assessment before and after soil remediation obtained by applying different risk assessment models. This paper also includes many case studies on: (1 food safety risk assessment for brown rice growing in a HMs-contaminated site; (2 a tiered approach to health risk assessment for a contaminated site; (3 risk assessment for phytoremediation techniques applied in HMs-contaminated sites; and (4 soil remediation cost analysis for contaminated sites in Taiwan.

  16. Radiological assessment of radioactive contamination on private clothing

    International Nuclear Information System (INIS)

    In the very rare, cases where private clothing of persons working in a nuclear installation are inadvertently contaminated and this contamination is not detected when leaving the facility, there may be radiological consequences for this person as well as for members of his or her family. The VGB (Technische Vereinigung der Grosskraftwerksbetreiber) in Germany has investigated in detail the spread of contamination in nuclear power plants. Part of this evaluation programme was a radiological analysis which has been carried out by Brenk Systemplanung GmbH (Aachen/Germany). The radiological analysis started with the definition of the source term. It is highly unlikely that activities of more than 5 kBq 60Co could leave a plant undetected on the body or the clothes. Nevertheless activities up to 50 kBq and different nuclide vectors were regarded. It has been found that 60Co is the most important contaminant. The radiological analysis focusses on two types of contamination: particles and surface contamination. The pathways by which such a contamination can lead to an exposure by external irradiation or by ingestion depend on the type of contamination and are analysed in detail. For example, a particle could be retained in pockets or other parts of clothing and may lead to prolonged external irradiation until the piece of clothing is washed. The analysis is performed on the basis of conservative to realistic assumptions. In conclusion, the analysis has shown that especially particle contamination needs to be focussed on. However, by the advanced detection equipment in German plants doses which may pose a health hazard can safely be excluded. (authors)

  17. Assessment and treatment of external and internal radionuclide contamination

    International Nuclear Information System (INIS)

    The most serious problems arise from accidents involving radionuclide contamination. This was demonstrated by experience from the Chernobyl and Goiania accidents, where large groups of people were externally and internally contaminated and which demanded significant management efforts from the health and other authorities. It is important that radionuclide contamination be minimized, not only by preventive measures, but also by good medical management when an exposure has occurred. This is an updated Technical Document based upon the IAEA Safety Series No. 88 ''Medical Handling of Accidentally Exposed Individuals'' and IAEA-TECDOC-366 ''What the General Practitioner (MD) Should Know about Medical Handling of Overexposed Individuals''. 26 refs, 3 figs, 2 tabs

  18. Parker River National Wildlife Refuge Contaminant Assessment Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — IInformation presented in this report is final documentation of the 1992 environmental contaminants evaluation of water and sediments in the Parker River National...

  19. Assessment of SRS radiological liquid and airborne contaminants and pathways

    Energy Technology Data Exchange (ETDEWEB)

    Jannik, G.T.

    1997-04-01

    This report compiles and documents the radiological critical-contaminant/critical-pathway analysis performed for SRS. The analysis covers radiological releases to the atmosphere and to surface water, which are the principal media that carry contaminants off site. During routine operations at SRS, limited amounts of radionuclides are released to the environment through atmospheric and/or liquid pathways. These releases potentially result in exposure to offsite people. Though the groundwater beneath an estimated 5 to 10 percent of SRS has been contaminated by radionuclides, there is no evidence that groundwater contaminated with these constituents has migrated offsite (Arnett, 1996). Therefore, with the notable exception of radiological source terms originating from shallow surface water migration into site streams, onsite groundwater was not considered as a potential exposure pathway to offsite people.

  20. Reconnaissance assessment of contaminants in Pahranagat Valley, Lincoln County, Nevada

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 1995, U.S. Fish and Wildlife Service personnel initiated a study to identify and quantify potential human-induced environmental contaminant impacts to endangered...

  1. Assessment of SRS radiological liquid and airborne contaminants and pathways

    International Nuclear Information System (INIS)

    This report compiles and documents the radiological critical-contaminant/critical-pathway analysis performed for SRS. The analysis covers radiological releases to the atmosphere and to surface water, which are the principal media that carry contaminants off site. During routine operations at SRS, limited amounts of radionuclides are released to the environment through atmospheric and/or liquid pathways. These releases potentially result in exposure to offsite people. Though the groundwater beneath an estimated 5 to 10 percent of SRS has been contaminated by radionuclides, there is no evidence that groundwater contaminated with these constituents has migrated offsite (Arnett, 1996). Therefore, with the notable exception of radiological source terms originating from shallow surface water migration into site streams, onsite groundwater was not considered as a potential exposure pathway to offsite people

  2. Parker River National Wildlife Refuge Contaminant Assessment Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Information presented in this report is final documentation of the 1990 environmental contaminants evaluation of water, sediments, and fish in the Parker River...

  3. Assessment of potential contaminant threats to Iroquois National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The primary purpose of the NBS Manual is to provide a standardized and systematic approach for identifying existing or potential contaminant problems on National...

  4. Simulation and assessment of subsurface contamination caused by spill and leakage of petroleum products - a multiphase multicomponent modelling approach

    International Nuclear Information System (INIS)

    Leakage, spillage and failure of petroleum storage tanks and transport systems often lead to contamination of subsurface soil and groundwater. A method for an integrated approach to environmental risk assessment of subsurface contamination is introduced that can reflect uncertanties associated with simulation results, environmental guidelines and the resulting risks to human health. The reported research deals with: (1) the fate and transport of a pollutant in porous media under uncertainty; (2) the distribution of pollutant concentrations under natural attenuation; (3) relationships between drinking water and health risk guidelines; and (4) probabilistic quantification of health injury risks. The methodology is applied to a site contaminated by leaking underground storage tanks, and the probabilities of violating drinking water standards and excess lifetime cancer risk for benzene under conservative, medium and optimistic considerations were determined. Reasonable results were generated, which are useful for clarifying the potential health effects of using groundwater for domestic purposes, as well as providing support for the related risk management and remediation decision making. 27 refs., 8 figs., 4 tabs

  5. Baseline risk assessment of groundwater contamination at the Uranium Mill Tailings Site near Gunnison, Colorado

    International Nuclear Information System (INIS)

    This Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy's (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells. This risk assessment evaluates the most contaminated monitor wells at the processing site. It will be used to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the groundwater are cadmium, cobalt, iron, manganese, sulfate, uranium, and some of the products of radioactive decay of uranium

  6. Baseline risk assessment of ground water contamination at the uranium mill tailings site near Durango, Colorado

    International Nuclear Information System (INIS)

    This risk assessment evaluates the possibility of health and environmental risks from contaminated ground water at the uranium mill tailings site near Durango, Colorado. The former uranium processing site's contaminated soil and material were removed and placed at a disposal site located in Body Canyon, Colorado, during 1986--1991 by the US Departments of Energy's Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating the nature and extent of ground water contamination at the site. This risk assessment follows an approach similar to that used by the US Environmental Protection Agency. The first step is to determine what site-related contaminants are found in ground water samples. The next step in the risk assessment is to determine how much of these contaminants people might ingest if they got their drinking water from a well on the site. In accordance with standard practice for this type of risk assessment, the highest contaminant concentrations from the most contaminated wells are used. The risk assessment then explains the possible health problems that could result from this amount of contamination

  7. Baseline risk assessment of groundwater contamination at the Uranium Mill Tailings Site near Gunnison, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-01

    This Baseline Risk Assessment of Groundwater Contamination at the Uranium Mill Tailings Site Near Gunnison, Colorado evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells. This risk assessment evaluates the most contaminated monitor wells at the processing site. It will be used to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the groundwater are cadmium, cobalt, iron, manganese, sulfate, uranium, and some of the products of radioactive decay of uranium.

  8. Baseline risk assessment of ground water contamination at the uranium mill tailings site near Durango, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    1995-02-01

    This risk assessment evaluates the possibility of health and environmental risks from contaminated ground water at the uranium mill tailings site near Durango, Colorado. The former uranium processing site`s contaminated soil and material were removed and placed at a disposal site located in Body Canyon, Colorado, during 1986--1991 by the US Departments of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating the nature and extent of ground water contamination at the site. This risk assessment follows an approach similar to that used by the US Environmental Protection Agency. The first step is to determine what site-related contaminants are found in ground water samples. The next step in the risk assessment is to determine how much of these contaminants people might ingest if they got their drinking water from a well on the site. In accordance with standard practice for this type of risk assessment, the highest contaminant concentrations from the most contaminated wells are used. The risk assessment then explains the possible health problems that could result from this amount of contamination.

  9. Assessment of natural radioactivity and mass attenuation coefficients of brick and roofing tile used in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Damla, N., E-mail: nevzat.damla@batman.edu.tr [Batman University, Department of Physics, 72060 Batman (Turkey); Cevik, U.; Kobya, A.I. [Karadeniz Technical University, Department of Physics, 61080 Trabzon (Turkey); Celik, A. [Giresun University, Department of Physics, 28049 Giresun (Turkey); Celik, N. [Guemueshane University, Department of Physics Engineering, 29100 Guemueshane Turkey (Turkey); Yildirim, I. [Karadeniz Technical University, Department of Forest Industry, 61080 Tranzon (Turkey)

    2011-08-15

    In this study the distribution of natural radionuclides ({sup 226}Ra, {sup 232}Th, {sup 40}K) in brick and roofing tile samples commonly used as building materials in Turkey was measured by using gamma spectrometry. The activity concentrations, radium equivalent activities (Ra{sub eq}), representative level index, indoor absorbed dose rate in air values and annual effective dose due to the intake of the above-mentioned radionuclides in the brick and roofing tile samples were estimated to assess the radiation hazard for people living in dwellings made of the materials studied. The measured average activity concentrations of {sup 226}Ra, {sup 232}Th and {sup 40}K were 34 {+-} 14, 34 {+-} 13 and 462 {+-} 175 Bq.kg{sup -1}, respectively, for brick samples. For roofing tile, the average activity concentrations of {sup 226}Ra, {sup 232}Th and {sup 40}K were measured to be 34 {+-} 14, 33 {+-} 12 and 429 {+-} 161 Bq.kg{sup -1}, respectively. The concentrations for these natural radionuclides were compared with the reported data of other countries. The Ra{sub eq} values of all samples were lower than the limit of 370 Bq.kg{sup -1}, equivalent to a gamma dose of 1.5 mSv.a{sup -1} recommended by OECD. This study shows that the measured brick and roofing tile samples do not pose any significant source of radiation hazard and are safe to be used as building materials. Moreover, the experimental mass attenuation coefficients ({mu}/{rho}) of brick and roofing tile samples were determined in the energy range 80-1332 keV using the gamma ray transmission method. The experimental mass attenuation coefficients were compared with theoretical values obtained using XCOM. It was found that the computed values and the experimental results of this work are in good agreement with those reported in the literature. The chemical compositions and structural analysis (XRD) of the brick and roofing tile samples are also presented. - Highlights: > In this study, the distribution of natural

  10. Assessment of natural radioactivity and mass attenuation coefficients of brick and roofing tile used in Turkey

    International Nuclear Information System (INIS)

    In this study the distribution of natural radionuclides (226Ra, 232Th, 40K) in brick and roofing tile samples commonly used as building materials in Turkey was measured by using gamma spectrometry. The activity concentrations, radium equivalent activities (Raeq), representative level index, indoor absorbed dose rate in air values and annual effective dose due to the intake of the above-mentioned radionuclides in the brick and roofing tile samples were estimated to assess the radiation hazard for people living in dwellings made of the materials studied. The measured average activity concentrations of 226Ra, 232Th and 40K were 34 ± 14, 34 ± 13 and 462 ± 175 Bq.kg-1, respectively, for brick samples. For roofing tile, the average activity concentrations of 226Ra, 232Th and 40K were measured to be 34 ± 14, 33 ± 12 and 429 ± 161 Bq.kg-1, respectively. The concentrations for these natural radionuclides were compared with the reported data of other countries. The Raeq values of all samples were lower than the limit of 370 Bq.kg-1, equivalent to a gamma dose of 1.5 mSv.a-1 recommended by OECD. This study shows that the measured brick and roofing tile samples do not pose any significant source of radiation hazard and are safe to be used as building materials. Moreover, the experimental mass attenuation coefficients (μ/ρ) of brick and roofing tile samples were determined in the energy range 80-1332 keV using the gamma ray transmission method. The experimental mass attenuation coefficients were compared with theoretical values obtained using XCOM. It was found that the computed values and the experimental results of this work are in good agreement with those reported in the literature. The chemical compositions and structural analysis (XRD) of the brick and roofing tile samples are also presented. - Highlights: → In this study, the distribution of natural radionuclides in brick and roofing tile samples used in Turkey were studied. → Associated potential

  11. Analysis And Assessment Of The Security Method Against Incidental Contamination In The Collective Water Supply System

    OpenAIRE

    Szpak Dawid; Tchórzewska – Cieślak Barbara

    2015-01-01

    The paper presents the main types of surface water incidental contaminations and the security method against incidental contamination in water sources. Analysis and assessment the collective water supply system (CWSS) protection against incidental contamination was conducted. Failure Mode and Effects Analysis (FMEA) was used. The FMEA method allow to use the product or process analysis, identification of weak points, and implementation the corrections and new solutions for eliminating the sou...

  12. Assessing depleted uranium (DU) contamination of soil, plants and earthworms at UK weapons testing sites

    OpenAIRE

    Oliver, I.W.; Graham, M C; Mackenzie, A. B.; Ellam, R.M.; Farmer, J.G.

    2007-01-01

    Depleted uranium (DU) weapons testing programmes have been conducted at two locations within the UK. An investigation was therefore carried out to assess the extent of any environmental contamination arising from these test programmes using both alpha spectrometry and mass spectrometry techniques. Uranium isotopic signatures indicative of DU contamination were observed in soil, plant and earthworm samples collected in the immediate vicinity of test firing points and targets, but contamination...

  13. Bioremediation (Natural Attenuation and Biostimulation) of Diesel-Oil-Contaminated Soil in an Alpine Glacier Skiing Area

    OpenAIRE

    Margesin, R.; Schinner, F.

    2001-01-01

    We investigated the feasibility of bioremediation as a treatment option for a chronically diesel-oil-polluted soil in an alpine glacier area at an altitude of 2,875 m above sea level. To examine the efficiencies of natural attenuation and biostimulation, we used field-incubated lysimeters (mesocosms) with unfertilized and fertilized (N-P-K) soil. For three summer seasons (July 1997 to September 1999), we monitored changes in hydrocarbon concentrations in soil and soil leachate and the accompa...

  14. Ecological Risk Assessment of a Metal-Contaminated Area in the Tropics. Tier II: Detailed Assessment

    OpenAIRE

    Júlia Carina Niemeyer; Matilde Moreira-Santos; Rui Ribeiro; Michiel Rutgers; Marco Antonio Nogueira; Eduardo Mendes da Silva; José Paulo Sousa

    2015-01-01

    This study presents data on the detailed evaluation (tier 2) of a site-specific ecological risk assessment (ssERA) in a former smelter area contaminated with metals (Santo Amaro, Bahia, Brazil). Combining information from three lines of evidence (LoE), chemical (ChemLoE), ecotoxicological (EcotoxLoE) and ecological (EcoLoE), in the Triad approach, integrated risk values were calculated to rank sites and confirm the potential risk disclosed with tier 1. Risk values were calculated for the habi...

  15. Surfactant-Enhanced Phytoremediation of Soils Contaminated with Hydrophobic Organic Contaminants: Potential and Assessment

    Institute of Scientific and Technical Information of China (English)

    GAO Yan-Zheng; LING Wan-Ting; ZHU Li-Zhong; ZHAO Bao-Wei; ZHENG Qing-Song

    2007-01-01

    Phytoremediation is becoming a cost-effective technology for the in-situ clean up of sites polluted with hydrophobic organic contaminants (HOCs). The major factors limiting phytoremediation are the mass transfer, rate of plant uptake, and microbial biodegradation of HOCs. This article discusses the potential of surfactants to enhance desorption, plant uptake, and biodegradation of HOCs in the contaminated sites. Positive effects of surfactants on phytoremediation have been recently observed in greenhouse studies. The presence of some nonionic surfactants including polyoxyethylene sorbitan monooleate (Tween 80) and polyoxyethylene(23)dodecanol (Brij35) at relatively low concentrations resulted in significant positive effects on phytoremediation for pyrene-contaminated soil. However, the anionic surfactant (sodium dodecyl sulfate, SDS) and the cationic surfactant (cetyltrimethylammonium bromide, CTMAB) were not useful because of their phytotoxicity or low efficiency for surfactant-enhanced phytoremediation (SEPR). The mechanisms of SEPR for HOC-contaminated sites were evaluated by considering experimental observations. In view of concerns about the cost effectiveness and toxicity of surfactants to plants, more research is needed to enhance the use of SEPR technology.

  16. Assessing Contaminant Migration and Risk through Passive Interstitial Water Samplers

    International Nuclear Information System (INIS)

    Soils and sediments account for a large proportion of the contaminated materials being managed under cleanup programs across the country, including at sites addressed by the U.S. Department of Energy and U.S. Army Corps of Engineers. Costs for managing a single sediment site can approach $1 billion, and overall program costs could exceed the trillion-dollar mark. Thus, using realistic information for contaminant levels in the risk calculations used to guide cleanup decisions for these sites is crucial. The risk-based decisions for contaminated soils and sediments are typically based on bulk solid concentrations. The reason for using that metric in the equations applied to estimate exposure and risk to biota and humans is that it is relatively easy to measure. However, the bulk concentration does not address the actual bio-accessibility or bioavailability of the contaminants. This can result in a substantial overestimate of risk, leading to cleanup decisions that are much more conservative than warranted. Such decisions can translate to unnecessary excavation or dredging that causes significant environmental damage to those natural systems, thus having the opposite effect intended by health and environmental protection programs. More realistic values that represent the bioavailable fraction of contaminants in soil and sediment are clearly needed to guide more effective cleanup decisions. Passive interstitial water samplers have emerged as a practical way to address this need. (authors)

  17. Environmental and economic assessment of the agricultural land management state on the contaminated areas

    OpenAIRE

    O. Grynyk

    2013-01-01

    Ecological and economic assessment of the agricultural land management state in the contaminated areas has been given in the article. Directions for an agricultural production rehabilitation and agricultural land sustainable management in areas contaminated owing to Chernobyl accident have been offered

  18. Emerging contaminants: Presentations at the 2009 Toxicology and Risk Assessment Conference

    International Nuclear Information System (INIS)

    A session entitled 'Emerging Contaminants' was held in April 2009 in Cincinnati, OH at the 2009 Toxicology and Risk Assessment Conference. The purpose of the session was to share information on both programmatic and technical aspects associated with emerging contaminants. Emerging contaminants are chemicals or materials that are characterized by a perceived or real threat to human health or environment, a lack of published health standards or an evolving standard. A contaminant may also be 'emerging' because of the discovery of a new source, a new pathway to humans, or a new detection method or technology. The session included five speakers representing the Department of Defense (DoD), the Environmental Protection Agency (EPA), and each of the military services. The DoD created the Emerging Contaminant Directorate to proactively address environmental, health, and safety concerns associated with emerging contaminants. This session described the scan-watch-action list process, impact assessment methodology, and integrated risk management concept that DoD has implemented to manage emerging contaminants. EPA presented emerging trends in health risk assessment. Researchers made technical presentations on the status of some emerging contaminates in the assessment process (i.e. manganese, RDX, and naphthalene).

  19. Chemometric assessment of enhanced bioremediation of oil contaminated soils

    DEFF Research Database (Denmark)

    Soleimani, Mohsen; Farhoudi, Majid; Christensen, Jan H.

    2013-01-01

    Bioremediation is a promising technique for reclamation of oil polluted soils. In this study, six methods for enhancing bioremediation were tested on oil contaminated soils from three refinery areas in Iran (Isfahan, Arak, and Tehran). The methods included bacterial enrichment, planting, and addi......Bioremediation is a promising technique for reclamation of oil polluted soils. In this study, six methods for enhancing bioremediation were tested on oil contaminated soils from three refinery areas in Iran (Isfahan, Arak, and Tehran). The methods included bacterial enrichment, planting...... steranes were used for determining the level and type of hydrocarbon contamination. The same methods were used to study oil weathering of 2 to 6 ring polycyclic aromatic compounds (PACs). Results demonstrated that bacterial enrichment and addition of nutrients were most efficient with 50% to 62% removal...

  20. Preliminary Assessment Of Space Infrared Experiment's (SIRE) Potential For Contamination

    Science.gov (United States)

    Mah, D. L.; Muscari, J. A.

    1982-02-01

    This paper presents the results of a contamination analysis and computer modeling study performed for the Space Infrared Experiment (SIRE) using the Space Transport System (STS) Shuttle Orbiter as the launch vehicle for the proposed seven-day sortie mission. These results will provide an accurate description of the deposition levels on the telescope primary mirror and of the molecular number column density (NCD) along the telescope line-of-sight. The planned Helium Purge System was assumed not to be operating. The contribution to the contamination environment of any cargo element, other than SIRE and its pallet, was not considered in this study. The study considers five potential contamination sources, including the flash evaporator vent effluents and the vernier reaction control system (VCS) engines plume constituents.

  1. Assessment of contaminants in Dubai coastal region, United Arab Emirates

    Science.gov (United States)

    Al-Darwish, H. A.; Abd El-Gawad, E. A.; Mohammed, F. H.; Lotfy, M. M.

    2005-12-01

    Coastal uses and other human activities have inevitably impinged on the Gulf environment; therefore, these regions require continuous monitoring. The investigated area covered the maximum fragments of Dubai coastal region in the Arabian Gulf. The determination of major oxides and trace metal concentrations in Dubai sediments revealed three heavily and moderately contaminated regions. One is in the far northeastern part at Al-Hamriya Sts 1 3 and contaminated by Fe, Cu, Pb, and Zn; the second is in the mid-northeastern part at Dry Docks and contaminated by Cu, Ni, Pb, and Zn; and finally, the third is in the near southwestern part at Dubal and contaminated by Fe, Mg, Cr, Ni, and Zn. Al-Hamriya St 3 represented the highest values of Cu, Pb, and Zn, whereas Dubal exhibited the maximum values of Fe, Mg, Ba, Cr, Mn, Ni, and V. The anthropogenic discharge and natural deposits are the main sources of contamination. In general, all trace and major elements showed the minimal levels at Jebel Ali Sanctuary (Sts 11, 12, 13) except for Sr and Ca, which showed their maximum values. The highest concentrations of Ca and Sr are mainly attributed to carbonate gravel sands and sands, which cover most stations. Each of V and Ni showed negative correlation with TPH, which may be indicated that the source of oil contamination in the region is not related to crude oil but mostly attributable to anthropogenic sources. The significant positive correlation, which was found between trace metals and TOC indicates that organic matter plays an important role in the accumulation of trace metals in case of Cu, Zn, and Pb.

  2. The assessment of site contamination using mobile gamma ray spectrometry

    International Nuclear Information System (INIS)

    3,700 measurements were made on a site of area in excess of 10 Ha using 'LARCH', the Large Area Radioactive Characterisation system. LARCH is a mobile system that combines the use of high resolution gamma spectroscopy with automated mapping techniques to generate a radiation contamination map of the surveyed area. The advantages of using high resolution gamma spectrometry, the means of correcting for contributions from radioactive plant, and the interpretation of results are presented. The techniques used permit a rapid and cost-effective location, identification and quantification of radioactive contamination or demonstration of compliance with clearance criteria. Possible applications of LARCH to other situations in site restoration are discussed. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-02-27

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

  4. Contaminants assessment of the Corpus Christi Bay Complex, Texas, 1988-1989

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The U.S. Fish & Wildlife Service-Ecological Services, Corpus Christi Field Office conducted baseline contaminants assessments of sediments and biota from the...

  5. SURROGATE SPECIES IN ASSESSING CONTAMINANT RISK FOR ENDANGERED FISHES, INCLUDING INTERSPECIES TOXICITY CORRELATIONS

    Science.gov (United States)

    Rainbow trout, fathead minnows, and sheepshead minnows were tested as surrogate species to assess contaminant risk for 17 endangered fishes and one toad species. Acute toxicity tests were conducted with carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin in accorda...

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

    DEFF Research Database (Denmark)

    Lemming, Gitte

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

  7. Detection of occult vertebral fractures by quantitative assessment of bone marrow attenuation values at MDCT

    International Nuclear Information System (INIS)

    Objectives: To determine a cut-off value of Hounsfield attenuation units (HU) at multidetector computed tomography (MDCT) for valid and reliable detection of bone marrow oedema (BME) related to occult vertebral fractures. Methods: 36 patients underwent both MDCT and Magnetic Resonance Imaging (MRI) for evaluation of vertebral fractures of the thoracolumbar spine and were included in this retrospective study. Two readers independently assessed HU values at MDCT in a total of 196 vertebrae. Reliability was assessed by intraclass correlation coefficient and Bland–Altman analysis. For each patient we determined the vertebra with the lowest HU value and calculated the HU-difference to each other vertebral body. HU-differences were subjected to receiver operating characteristic (ROC) curve analysis to determine the diagnostic accuracy for detection of BME as determined by MRI, which served as the reference standard. Results of HU-measurements were compared with standard visual evaluation of MDCT. Results: HU measurements demonstrated a high interrater reliability (ICC = 0.984). ROC curve analysis (AUC = 0.978) exhibited an ideal cut-off value of 29.6 HU for detection of BME associated with vertebral fractures with an accuracy of 97.4% as compared to 93.4% accuracy of visual evaluation. Particularly, HU-measurements increased the sensitivity for detection of vertebral fractures from 78.0% to 92.7% due to the detection of 7 of 9 occult fractures that were missed by visual evaluation alone. Conclusions: Assessing bone marrow density by HU measurements using the cut-off of 29.6 HU is a valid and reliable tool for detection of BME related to occult vertebral fractures in MDCT. The introduced technique may allow more accurate treatment decisions and may make further diagnostic work-up with MRI unnecessary

  8. Detection of occult vertebral fractures by quantitative assessment of bone marrow attenuation values at MDCT

    Energy Technology Data Exchange (ETDEWEB)

    Henes, Frank Oliver, E-mail: f.henes@uke.de [Department of Diagnostic and Interventional Radiology, Center for Radiology and Endoscopy, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Groth, Michael [Department of Diagnostic and Interventional Neuroradiology, Center for Radiology and Endoscopy, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Kramer, Harald [Department of Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistr. 15, 81377 Munich (Germany); Department of Radiology, University of Wisconsin – Madison, Clinical Science Center, 600 Highland Avenue, Madison, WI 53792 (United States); Schaefer, Christian [Department of Trauma-, Hand- and Reconstructive Surgery, Spine Center, Center for Surgical Sciences, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246 Hamburg (Germany); Regier, Marc; Derlin, Thorsten; Adam, Gerhard; Bannas, Peter [Department of Diagnostic and Interventional Radiology, Center for Radiology and Endoscopy, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany)

    2014-01-15

    Objectives: To determine a cut-off value of Hounsfield attenuation units (HU) at multidetector computed tomography (MDCT) for valid and reliable detection of bone marrow oedema (BME) related to occult vertebral fractures. Methods: 36 patients underwent both MDCT and Magnetic Resonance Imaging (MRI) for evaluation of vertebral fractures of the thoracolumbar spine and were included in this retrospective study. Two readers independently assessed HU values at MDCT in a total of 196 vertebrae. Reliability was assessed by intraclass correlation coefficient and Bland–Altman analysis. For each patient we determined the vertebra with the lowest HU value and calculated the HU-difference to each other vertebral body. HU-differences were subjected to receiver operating characteristic (ROC) curve analysis to determine the diagnostic accuracy for detection of BME as determined by MRI, which served as the reference standard. Results of HU-measurements were compared with standard visual evaluation of MDCT. Results: HU measurements demonstrated a high interrater reliability (ICC = 0.984). ROC curve analysis (AUC = 0.978) exhibited an ideal cut-off value of 29.6 HU for detection of BME associated with vertebral fractures with an accuracy of 97.4% as compared to 93.4% accuracy of visual evaluation. Particularly, HU-measurements increased the sensitivity for detection of vertebral fractures from 78.0% to 92.7% due to the detection of 7 of 9 occult fractures that were missed by visual evaluation alone. Conclusions: Assessing bone marrow density by HU measurements using the cut-off of 29.6 HU is a valid and reliable tool for detection of BME related to occult vertebral fractures in MDCT. The introduced technique may allow more accurate treatment decisions and may make further diagnostic work-up with MRI unnecessary.

  9. Control and assessment of the hydrocarbon contamination of Ukrainian soils

    Science.gov (United States)

    Miroshnichenko, N. N.

    2008-05-01

    Regularities governing the self-purification of soils from oil hydrocarbons, as well as migration of hydrocarbons, and the effect on the water-physical properties and fertility of soils were revealed in a series of experiments. A system of ecological, economic, and reclamation standards was proposed for regulating economic activities in the case of soil contamination with hydrocarbons.

  10. Assessment of exposures to fecally-contaminated recreational water

    Science.gov (United States)

    Exposure to fecally-contaminated recreational waters can pose a health risk to swimmers and other recreators. Since 2003, we have interviewed nearly 27,000 respondents at seven beaches impacted by treated sewage discharge. Information was collected about the duration and exposure...

  11. Assessment of the radiological impact of contaminated discharges

    Energy Technology Data Exchange (ETDEWEB)

    Sweeck, L.; Zeevaert, T.

    1996-09-18

    A biosphere model has been used to calculate the release of radionuclides from contaminated soils and their dose impact on critical individuals in the environment. Normal evolution and accidental scenarios are considered. The objective of the model is to provide an indication of the radiological risk rather than to predict its future impact.

  12. Formation of secondary hematite and its role in attenuation of contaminants at mine tailings: review and comparison of sites in Zambia and Namibia

    Directory of Open Access Journals (Sweden)

    Sracek eOndra

    2015-01-01

    Full Text Available Mine tailings in African countries Zambia and Namibia have been investigated with an objective to determine the role of secondary hematite in immobilization of contaminants. Two sites, Chambishi and Mindolo, are located in the Copperbelt in Zambia with relatively humid climates and two sites, Berg Aukas and Kombat, are in Namibia, where the climate is semiarid. At the Chambishi site which is about 40 years old, a hardpan composed of hematite and gypsum has formed at a depth of about 60 cm and large amounts of Cu and Co have been deposited. At the much younger Mindolo site (30 years old, but most V remains in primary descloizite, embedded in a carbonate matrix while a relatively small amount of released V is incorporated into hematite. In contrast, released Zn and Pb are incorporated mainly into smithsonite and cerussite, which are less stable from an environmental viewpoint. Finally, at the Kombat mine tailings (< 5 years old, As released from pyrite is also incorporated into hematite, but Cu released by dissolution of chalcopyrite and bornite has precipitated as malachite, which is less stable than hematite. Water-leached concentrations of contaminants such as Cu, Zn, and Pb (also present in some carbonate phases are an order of magnitude higher than water-leached concentrations of V and As which are bound to crystalline ferric minerals such as hematite and soluble only in the aqua regia fraction of sequential extraction. It seems that rapid formation of hematite under tropical climate conditions and incorporation of contaminants into this mineral phase is favourable for attenuation of released contaminants. These findings have implications at other mining sites with similar climates in Africa, South America and Asia.

  13. ASSESSMENT OF SURFACE WATER QUALITY IN AN ARSENIC CONTAMINATED VILLAGE

    Directory of Open Access Journals (Sweden)

    Kumud C. Saikia

    2012-01-01

    Full Text Available Arsenic contamination of ground water has occurred in various parts of the world, becoming a menace in the Ganga-Meghna-Brahmaputra basin (West Bengal and Assam in India and Bangladesh. Recently arsenic has been detected in Cachar and Karimganj districts of barak valley, Assam, bordering Bangladesh. In this area coli form contamination comprises the major constraint towards utilization of its otherwise ample surface water resources. The local water management exploited ground water sources using a centralized piped water delivery scheme without taking into account the geologically arsenic-prone nature of the sediments and aquifers in this area. Thus surface water was the suggestive alternative for drinking water in this area. The present study investigated surface water quality and availability in a village of Karimganj district, Assam, India contaminated with arsenic for identifying the potential problems of surface water quality maintenance so that with effective management safe drinking water could be provided. The study revealed that the area was rich in freshwater ecosystems which had all physico-chemical variables such as water temperature, pH, DO, total alkalinity, free CO2, heavy metals like lead, chromium and cadmium within WHO standards. In contrast, coli form bacteria count was found far beyond permissible limit in all the sources. Around 60% people of the village preferred ground water for drinking and only 6% were aware of arsenic related problems. The problem of bacterial contamination could be controlled by implementing some ameliorative measures so that people can safely use surface water. Inhabitants of the two districts should be given proper education regarding arsenic contamination and associated health risk. Effluents should be treated to acceptable levels and standards before discharging them into natural streams.

  14. Assessment of water use for estimating exposure to tap water contaminants.

    OpenAIRE

    Shimokura, G H; Savitz, D. A.; Symanski, E

    1998-01-01

    Epidemiological studies examining the association between exposure to tap water contaminants (such as chlorination by-products) and disease outcomes (such as cancer and adverse reproductive outcomes) have been limited by inaccurate exposure assessment. Failure to take into account the variation in beverage and tap water consumption and exposure to volatile contaminants through inhalation and dermal absorption can introduce misclassification in assessing the association between exposure to tap...

  15. Assessing Anthracene and Arsenic Contamination within Buffalo River Sediments

    OpenAIRE

    Adrian Gawedzki; K. Wayne Forsythe

    2012-01-01

    Anthracene and arsenic contamination concentrations at various depths in the Buffalo River were analyzed in this study. Anthracene is known to cause damage to human skin and arsenic has been linked to lung and liver cancer. The Buffalo River is labelled as an Area of Concern defined by the Great Lakes Water Quality Agreement between Canada and the United States. It has a long history of industrial activity located in its near vicinity that has contributed to its pollution. An ordinary kriging...

  16. Emerging contaminants in groundwater: occurrence and risk assessment

    OpenAIRE

    Stuart, Marianne; Lapworth, Dan

    2012-01-01

    Emerging groundwater contaminants (EGCs) are compounds previously not considered or known to be significant (in terms of distribution and/or concentration) but now being more widely detected. As analytical techniques improve, previously undetected micropollutants are observed. There is a paucity of information regarding EGC occurrence in groundwaters compared to surface waters. The types of organic micropollutants which can be found include, pesticides, pharmaceuticals, caffeine and nicotin...

  17. Assessment of Metal Contaminants in River Kubanni Zaria, Nigeria

    Directory of Open Access Journals (Sweden)

    A.W. Butu

    2012-10-01

    Full Text Available This study examines the levels of concentration of metal pollutants in river Kubanni and the health implications of these metal contaminants. The main sources of data for the study were sediments from long profile of the river and WHO guidelines for drinking water that were obtained from relevant literatures and internet. The samples were prepared and Instrumental Nitrogen Activation Analysis (INAA was adopted in the analysis of the data using Nigerian Research Reactor - 1 (NIRR-1. Twenty nine metal contaminants (Mg, Al, Ca, Ti, V, Mn, Dy, Na, K, As, Br, La, Sm, Yb, U, Sc, Cr, Zn, Fe, Co, Rb, Cs, Ba, Eu, Lu, Hg, Ta, Sb and Th were identified in the river. The safety levels of the metal contaminants were examined by comparing the obtained values with WHO guidelines for domestic water and it was observed that the river is getting polluted by Al, Mn, As, U, Cr, Fe, Co, Zn, Ba, Na and Sb with severe health implications on the consumers of the river Kubanni water. The levels of concentration of Mg, Ca, Ti, V, Dy, K, Br, La, Sm, Yb, Sc, Hg, Ta, Rb, Cs, Eu, Lu and Th are also high, although there is no WHO standard for comparison, some of these metals are suspected to be harmful to humans when consumed in excess quantity.

  18. Environmental isotopes (N, S, C, O, D) to determine natural attenuation processes in nitrate contaminated waters: Example of Osona (NE Spain)

    International Nuclear Information System (INIS)

    Nitrate-contaminated groundwater from an aquifer in the Osona region (NE Spain) was chemically and isotopically (δ15NNO3,δ18ONO3,δ34SSO4,δ18OSO4, δD, δ18OH2O and δ13CDIC) characterized. Diffuse- NO3- contamination reached values of 366 mg/L. Nearly 75% of the 37 sampled sites had higher concentrations than the 50 mg/L in NO3- limit for drinking water. To identify the source of pollution δ15NNO3 and δ18ONO3 were used with results, for most samples, in the range of pig manure NO3-. Nitrification processes were evaluated by means of the δ18O of NO3- and water. Isotopic data suggested that natural attenuation of NO3- was taking place. This process was confirmed using the δ18ONO3 coupled with the NO3-/Cl- ratio, avoiding the influence of continuous NO3- inputs. A further insight on denitrification processes was obtained by analyzing the ions involved in denitrification reactions. Although the role of organic matter oxidation could neither be confirmed nor discarded, this approach showed a link between denitrification and pyrite oxidation. Therefore, in areas with no adequate infrastructure (e.g. multipiezometers), such as the one studied, this approach could be useful for implementing better water management

  19. Problems in assessing the risks of mixtures of contaminants in drinking water

    International Nuclear Information System (INIS)

    In conducting risk assessments on drinking water contaminants, the U.S. Environmental Protection Agency (EPA) attempts to evaluate all available toxicity data to develop Health Advisory (HA) and Maximum Contaminant Level Goal (MCLG) values. The EPA often has grappled with the issues surrounding the toxicity of chemical mixtures, including radioactive contaminants, nitrate/nitrite, and trihalomethanes (THMs). In evaluating the toxicity of chemical mixtures, the EPA's immediate concern is whether the individual HA values and MCLGs are protecting public health when multiple contaminants are present in drinking water. Potential toxic interactions between drinking water contaminants are difficult to predict because experimental studies are generally performed only at high doses relative to environmental levels. Although the contamination of drinking water involves mixtures of contaminants, drinking water regulations are generally based on an assessment of the risks of individual contaminants. This paper discusses three issues of major concern to the EPA: the synergistic effects of solvent mixtures, vehicle effects in laboratory studies, and setting standards for essential trace nutrients where the absorption and/or toxicity are affected by an individual's nutritional status or other dietary components. 12 references

  20. Heavy Metal Contamination Assessment and Partition for Industrial and Mining Gathering Areas

    Directory of Open Access Journals (Sweden)

    Yang Guan

    2014-07-01

    Full Text Available Industrial and mining activities have been recognized as the major sources of soil heavy metal contamination. This study introduced an improved Nemerow index method based on the Nemerow and geo-accumulation index. Taking a typical industrial and mining gathering area in Tianjin (China as example, this study then analyzed the contamination sources as well as the ecological and integrated risks. The spatial distribution of the contamination level and ecological risk were determined using Geographic Information Systems. The results are as follows: (1 Zinc showed the highest contaminant level in the study area; the contamination levels of the other seven heavy metals assessed were relatively lower. (2 The combustion of fossil fuels and emissions from industrial and mining activities were the main sources of contamination in the study area. (3 The overall contamination level of heavy metals in the study area ranged from heavily contaminated to extremely contaminated and showed an uneven distribution. (4 The potential ecological risk showed an uneven distribution, and the overall ecological risk level ranged from low to moderate. This study also emphasized the importance of partition in industrial and mining areas, the extensive application of spatial analysis methods, and the consideration of human health risks in future studies.

  1. Assessing Anthracene and Arsenic Contamination within Buffalo River Sediments

    Directory of Open Access Journals (Sweden)

    Adrian Gawedzki

    2012-01-01

    Full Text Available Anthracene and arsenic contamination concentrations at various depths in the Buffalo River were analyzed in this study. Anthracene is known to cause damage to human skin and arsenic has been linked to lung and liver cancer. The Buffalo River is labelled as an Area of Concern defined by the Great Lakes Water Quality Agreement between Canada and the United States. It has a long history of industrial activity located in its near vicinity that has contributed to its pollution. An ordinary kriging spatial interpolation technique was used to calculate estimates between sample locations for anthracene and arsenic at various depths. The results show that both anthracene and arsenic surface sediment (0–30 cm is less contaminated than all subsurface depths. There is variability of pollution within the different subsurface levels (30–60 cm, 60–90 cm, 90–120 cm, 120–150 cm and along the river course, but major clusters are identified throughout all depths for both anthracene and arsenic.

  2. MERCURY CONTAMINATED MATERIAL DECONTAMINATION METHODS: INVESTIGATION AND ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    M.A. Ebadian, Ph.D.

    2001-01-01

    Over the years mercury has been recognized as having serious impacts on human health and the environment. This recognition has led to numerous studies that deal with the properties of various mercury forms, the development of methods to quantify and speciate the forms, fate and transport, toxicology studies, and the development of site remediation and decontamination technologies. This report reviews several critical areas that will be used in developing technologies for cleaning mercury from mercury-contaminated surfaces of metals and porous materials found in many DOE facilities. The technologies used for decontamination of water and mixed wastes (solid) are specifically discussed. Many technologies that have recently appeared in the literature are included in the report. Current surface decontamination processes have been reviewed, and the limitations of these technologies for mercury decontamination are discussed. Based on the currently available technologies and the processes published recently in the literature, several processes, including strippable coatings, chemical cleaning with iodine/iodide lixiviant, chemisorbing surface wipes with forager sponge and grafted cotton, and surface/pore fixation through amalgamation or stabilization, have been identified as potential techniques for decontamination of mercury-contaminated metal and porous surfaces. Their potential merits and applicability are discussed. Finally, two processes, strippable coatings and chemical cleaning with iodine/iodide lixiviant, were experimentally investigated in Phase II of this project.

  3. Assessment of combined electro-nanoremediation of molinate contaminated soil.

    Science.gov (United States)

    Gomes, Helena I; Fan, Guangping; Mateus, Eduardo P; Dias-Ferreira, Celia; Ribeiro, Alexandra B

    2014-09-15

    Molinate is a pesticide widely used, both in space and time, for weed control in rice paddies. Due to its water solubility and affinity to organic matter, it is a contaminant of concern in ground and surface waters, soils and sediments. Previous works have showed that molinate can be removed from soils through electrokinetic (EK) remediation. In this work, molinate degradation by zero valent iron nanoparticles (nZVI) was tested in soils for the first time. Soil is a highly complex matrix, and pollutant partitioning between soil and water and its degradation rates in different matrices is quite challenging. A system combining nZVI and EK was also set up in order to study the nanoparticles and molinate transport, as well as molinate degradation. Results showed that molinate could be degraded by nZVI in soils, even though the process is more time demanding and degradation percentages are lower than in an aqueous solution. This shows the importance of testing contaminant degradation, not only in aqueous solutions, but also in the soil-sorbed fraction. It was also found that soil type was the most significant factor influencing iron and molinate transport. The main advantage of the simultaneous use of both methods is the molinate degradation instead of its accumulation in the catholyte. PMID:24946031

  4. Establishing indices for groundwater contamination risk assessment in the vicinity of hazardous waste landfills in China

    International Nuclear Information System (INIS)

    Groundwater contamination by leachate is the most damaging environmental impact over the entire life of a hazardous waste landfill (HWL). With the number of HWL facilities in China rapidly increasing, and considering the poor status of environmental risk management, it is imperative that effective environmental risk management methods be implemented. A risk assessment indices system for HWL groundwater contamination is here proposed, which can simplify the risk assessment procedure and make it more user-friendly. The assessment framework and indices were drawn from five aspects: source term, underground media, leachate properties, risk receptors and landfill management quality, and a risk assessment indices system consisting of 38 cardinal indicators was established. Comparison with multimedia models revealed that the proposed indices system was integrated and quantitative, that input data for it could be easily collected, and that it could be widely used for environmental risk assessment (ERA) in China. - Highlights: ► No comprehensive environmental risk assessment method for hazardous waste management is proposed in China. ► An assessment indices system is established for groundwater contamination in the vicinity of hazardous waste landfill. ► All indicators are quantitative and applicable in China. - Capsule: This research identified critical indices and established a system for environmental risk assessment for groundwater contamination in the vicinity of HWLs in China.

  5. Influence of Carbon and Microbial Community Priming on the Attenuation of Uranium in a Contaminated Floodplain Aquifer

    Energy Technology Data Exchange (ETDEWEB)

    Mouser, Paula J.; N' Guessan, A. Lucie; Qafoku, Nikolla; Sinha, M.; Williams, K. H.; Dangelmayr, M.; Resch, Charles T.; Peacock, Aaron D.; Wang, Zheming; Figueroa, Linda A.; Long, P. E.

    2015-07-01

    The capacity for subsurface sediments to sequester metal contaminants, such as uranium (U), and retain them after bioremediation efforts are completed is critical to site stewardship. Sediments enriched in natural organic matter are capable of sequestering significant quantities of U, but may also serve as sources to the aquifer, contributing to plume persistence. Two types of sediments were compared to better understand the mechanisms contributing to the sequestration and release of U in the presence of organic matter. Artificially bioreduced sediments were retrieved from a field experimental plot previously stimulated with acetate while naturally bioreduced sediments were collected from a location enriched in organic matter but never subject to acetate amendment. Batch incubations demonstrated that the artificially bioreduced sediments were primed to rapidly remove uranium from the groundwater whereas naturally bioreduced sediments initially released a sizeable portion of sediment U before U(VI)-removal commenced. Column experiments confirmed that U release persisted for 65 pore volumes in naturally bioreduced sediments, demonstrating the sink-source behavior of this sediment. Acetate addition to artificially bioreduced sediments shifted the microbial community from one dominated by sulfate-reducing bacteria within Desulfobacteraceae to the iron-reducing family Geobacteraceae and Firmicutes during U(VI) reduction. In contrast, initial Geobacteraceae communities innaturally reduced sediments were replaced by clone sequences with similarity to opportunistic Pseudomonas spp. during U release, while U(VI) removal occurred concurrent with enrichment of Firmicutes. These investigations stress the importance of characterizing zones with heterogeneous carbon pools at U contaminated sites prior to the determination of a remedial strategy.

  6. Baseline risk assessment of groundwater contamination at the uranium mill tailings site near Shiprock, New Mexico

    International Nuclear Information System (INIS)

    This report evaluates potential impact to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site were placed in a disposal cell on the site in 1986 by the US Department of Energy's (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This risk assessment is the first document specific to this site for the Groundwater Project. This risk assessment follows the approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the floodplain groundwater are arsenic, magnesium, manganese, nitrate, sodium, sulfate, and uranium. The complete list of contaminants associated with the terrace groundwater could not be determined due to the lack of the background groundwater quality data. However, uranium, nitrate, and sulfate are evaluated since these chemicals are clearly associated with uranium processing and are highly elevated compared to regional waters. It also could not be determined if the groundwater occurring in the terrace is a usable water resource, since it appears to have originated largely from past milling operations. The next step in the risk assessment is to estimate how much of these contaminants people would be exposed to if a drinking well were installed in the contaminated groundwater or if there were exposure to surface expressions of contaminated water. Potential exposures to surface water include incidental contact with contaminated water or sediments by children playing on the floodplain and consumption of meat and milk from domestic animals grazed and watered on the floodplain

  7. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Riverton, Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    This Risk Assessment evaluated potential impacts to public health or the environment caused by ground water contamination at the former uranium mill processing site. In the first phase of the U.S. Department of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Project, the tailing and other contaminated material at this site were placed in a disposal cell near the Gas Hills Plant in 1990. The second phase of the UMTRA Project is to evaluate ground water contamination. This risk assessment is the first site-specific document to evaluate potential health and environmental risks for the Riverton site under the Ground Water Project; it will help determine whether remedial actions are needed for contaminated ground water at the site.

  8. Alpha contamination assessment for D ampersand D activities: Monitoring pipe interiors

    International Nuclear Information System (INIS)

    We have developed a prototype instrument capable of assessing alpha-emitting contamination on interior surfaces of ducts, pipes, tanks, and other enclosed volumes without inserting a probe. Air is drawn through the potentially contaminated volume and then through a detection grid, where ions created in the air by alpha particles are collected and the resulting charge measured with a sensitive electrometer. A filter at the intake end of the contaminated volume excludes externally created ions, so only ions generated inside the volume are detected. We have studied the response of this prototype in initial experiments using calibrated alpha sources with various pipe diameters and configurations, air flows, and source locations in the pipes. The results of these experiments indicate that this method can be an effective approach to assessing internal contamination

  9. Baseline risk assessment for groundwater contamination at the uranium mill tailings site near Monument Valley, Arizona

    International Nuclear Information System (INIS)

    This baseline risk assessment evaluates potential impact to public health or the environment resulting from groundwater contamination at the former uranium mill processing site near Monument Valley, Arizona. The tailings and other contaminated material at this site are being relocated and stabilized in a disposal cell at Mexican Hat, Utah, through the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. The tailings removal is planned for completion by spring 1994. After the tailings are removed, groundwater contamination at the site will continue to be evaluated. This risk assessment is the first document specific to this site for the Groundwater Project. It will be used to assist in determining what remedial action is needed for contaminated groundwater at the site

  10. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Riverton, Wyoming

    International Nuclear Information System (INIS)

    This Risk Assessment evaluated potential impacts to public health or the environment caused by ground water contamination at the former uranium mill processing site. In the first phase of the U.S. Department of Energy's Uranium Mill Tailings Remedial Action (UMTRA) Project, the tailing and other contaminated material at this site were placed in a disposal cell near the Gas Hills Plant in 1990. The second phase of the UMTRA Project is to evaluate ground water contamination. This risk assessment is the first site-specific document to evaluate potential health and environmental risks for the Riverton site under the Ground Water Project; it will help determine whether remedial actions are needed for contaminated ground water at the site

  11. Assessment of the implications of radium contamination of Dalgety Bay beach and foreshore

    International Nuclear Information System (INIS)

    This report describes the research work undertaken for the Scottish Office Environment Department to assess the implications of radium-226 contamination at Dalgety Bay in the Firth of Forth. The research involved a detailed profile of beach usage and type of users of the area; a field survey and sampling programme to identify the current extent and distribution of radioactive contamination in some areas round Dalgety Bay; laboratory studies to determine the chemical content of samples taken from the area, and leaching studies to establish how long it would take for the radioactive components to dissolve out of the particles found when exposed to sea water and hydrochloric acid. In the light of this data, an assessment was made of the maximum risk members of the local community were exposed to should they inhale or swallow a contaminated particle. These have been compared to the target risks used for environmental contamination situations. (UK)

  12. Supplementary guidance for the investigation and risk-assessment of potentially contaminated sediments

    Energy Technology Data Exchange (ETDEWEB)

    Baker, K.; Spadaro, P.; Starr, J.; Thomas, J. [Arcadis, Arnhem (Netherlands); Hildenbrand, B. [Energy Institute, London (United Kingdom); Smith, J.W.N.; Dunk, M.; Grosjean, T.; De Ibarra, M.; Medve, A.; Den Haan, K.

    2013-11-15

    This report provides guidance on the investigation and assessment of potentially contaminated sediments, focusing on the inland, estuarine and coastal environments. It is designed as a complementary, technical companion document to Energy Institute and CONCAWE (2013) report 'Guidance on characterising, assessing and managing risks associated with potentially contaminated sediments' (Report E1001). It highlights a number of significant challenges associated with assessing the aquatic and water bottom environment, which means that a sediment assessment should not be undertaken lightly. Where a decision is taken to undertake a site assessment, this report promotes the use of an iterative process of Conceptual Site Model (CSM) development, data collection, data evaluation and a continuous CSM refinement, taking into account the results obtained. Risk-based assessment is described throughout the report, entailing four tiers of assessment, which progress from a qualitative assessment (Tier 0) through to a detailed cause-attribution assessment (Tier 3), in which the decrease in uncertainty in the assessment process is balanced against the increased costs and timescales with progress to a higher tier assessment. The application of this evidence-driven risk-based approach to sediment site management, including remedial control measures, should help to overcome at least some of the challenges associated with contaminants in sediment sites in Europe, and promote a sustainable approach to sediment management on a case-by-case basis.

  13. Assessment of human burn scars with optical coherence tomography by imaging the attenuation coefficient of tissue after vascular masking.

    Science.gov (United States)

    Gong, Peijun; McLaughlin, Robert A; Liew, Yih Miin; Munro, Peter R T; Wood, Fiona M; Sampson, David D

    2014-02-01

    The formation of burn-scar tissue in human skin profoundly alters, among other things, the structure of the dermis. We present a method to characterize dermal scar tissue by the measurement of the near-infrared attenuation coefficient using optical coherence tomography (OCT). To generate accurate en face parametric images of attenuation, we found it critical to first identify (using speckle decorrelation) and mask the tissue vasculature from the three-dimensional OCT data. The resulting attenuation coefficients in the vasculature-masked regions of the dermis of human burn-scar patients are lower in hypertrophic (3.8±0.4  mm(-1)) and normotrophic (4.2±0.9  mm(-1)) scars than in contralateral or adjacent normal skin (6.3±0.5  mm(-1)). Our results suggest that the attenuation coefficient of vasculature-masked tissue could be used as an objective means to assess human burn scars. PMID:24192908

  14. Baseline risk assessment of ground water contamination at the uranium mill tailings site near Canonsburg, Pennsylvania

    International Nuclear Information System (INIS)

    This baseline risk assessment evaluates potential impacts to public health and the environment resulting from ground water contamination from past activities at the former uranium processing site in Canonsburg, Pennsylvania. The US Department of Energy Uranium Mill Tailings Remedial Action (UMTRA) Project has placed contaminated material from this site in an on-site disposal cell. Currently, the UMTRA Project is evaluating ground water contamination. This risk assessment is the first document specific to this site for the UMTRA Ground Water Project. Currently, no domestic or drinking water well tap into contaminated ground water of the two distinct ground water units: the unconsolidated materials and the bedrock. Because there is no access, no current health or environmental risks are associated with the direct use of the contaminated ground water. However, humans and ecological organisms could be exposed to contaminated ground water if a domestic well were to be installed in the unconsolidated materials in that part of the site being considered for public use (Area C). The first step is evaluating ground water data collected from monitor wells at the site. For the Canonsburg site, this evaluation showed the contaminants in ground water exceeding background in the unconsolidated materials in Area C are ammonia, boron, calcium, manganese, molybdenum, potassium, strontium, and uranium

  15. Baseline risk assessment of ground water contamination at the uranium mill tailings site near Canonsburg, Pennsylvania

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    This baseline risk assessment evaluates potential impacts to public health and the environment resulting from ground water contamination from past activities at the former uranium processing site in Canonsburg, Pennsylvania. The US Department of Energy Uranium Mill Tailings Remedial Action (UMTRA) Project has placed contaminated material from this site in an on-site disposal cell. Currently, the UMTRA Project is evaluating ground water contamination. This risk assessment is the first document specific to this site for the UMTRA Ground Water Project. Currently, no domestic or drinking water well tap into contaminated ground water of the two distinct ground water units: the unconsolidated materials and the bedrock. Because there is no access, no current health or environmental risks are associated with the direct use of the contaminated ground water. However, humans and ecological organisms could be exposed to contaminated ground water if a domestic well were to be installed in the unconsolidated materials in that part of the site being considered for public use (Area C). The first step is evaluating ground water data collected from monitor wells at the site. For the Canonsburg site, this evaluation showed the contaminants in ground water exceeding background in the unconsolidated materials in Area C are ammonia, boron, calcium, manganese, molybdenum, potassium, strontium, and uranium.

  16. Fungal Peptaibiotics: Assessing Potential Meteoritic Amino Acid Contamination

    Science.gov (United States)

    Elsila, J. E.; Callahan, M. P.; Glavin, D. P.; Dworkin, J. P.; Bruckner, H.

    2010-01-01

    The presence of non-protein alpha-dialkyl-amino acids such as alpha-aminoisobutyric acid (alpha-A1B) and isovaline (Iva), which are relatively rare in the terrestrial biosphere, has long been used as an indication of the indigeneity of meteoritic amino acids, however, the discovery of alpha-AIB in peptides producers by a widespread group of filamentous fungi indicates the possibility of a terrestrial biotic source for the alpha-AIB observed in some meteorites. The alpha-AIB-containing peptides produced by these fungi are dubbed peptaibiotics. We measured the molecular distribution and stable carbon and nitrogen isotopic ratios for amino acids found in the total hydrolysates of four biologically synthesized peptaibiotics. We compared these aneasurenetts with those from the CM2 carbonaceous chondrite Murchison and from three Antarctic CR2 carbonaceous chondrites in order to understand the peptaibiotics as a potential source of meteoritic contamination.

  17. An assessment of metal contamination in Caspian Sea sediments

    International Nuclear Information System (INIS)

    Full text: The Caspian is the largest inland body of water in the world, containing some 44 % of the globe's inland waters. The Caspian Sea occupies a deep depression on the boundary between Asia and Europe with a water level at present 27 m below sea level. The main sources of pollution to the Caspian Sea have generally been considered to be offshore oil production and land-based sources, notably the Volga River. In this study heavy metal concentration and relationships between sedimentary components and metal concentration and relationships between different (various) heavy metal concentrations in sediment samples of Caspian sea were investigated to obtain information about the sources and degree of metal contamination Sediments samples from the stations were collected by Van Veen Grab fitted with stainless-steel jaws

  18. Unsaturated zone leaching models for assessing risk to groundwater of contaminated sites

    DEFF Research Database (Denmark)

    Troldborg, Mads; Binning, Philip John; Nielsen, Signe;

    2009-01-01

    , lateral gas diffusion, sorption and degradation; a simple one-dimensional screening model, and two one-dimensional radial gas diffusion models for use in simulating volatile organic contaminant diffusion in unsaturated soils with an impermeable cover. The models show that both degradation and diffusion......Risk assessments of sites contaminated with organic contaminants are typically conducted using models that ignore gas phase transport in the unsaturated zone. Here a general approach to developing analytical solutions to multiphase transport is presented. The approach is based on a combined gas and...

  19. A Bayesian belief network approach for assessing uncertainty in conceptual site models at contaminated sites

    DEFF Research Database (Denmark)

    Thomsen, Nanna Isbak; Binning, Philip John; McKnight, Ursula S.; Tuxen, Nina; Bjerg, Poul Løgstrup; Troldborg, Mads

    2016-01-01

    A key component in risk assessment of contaminated sites is in the formulation of a conceptual site model (CSM). A CSM is a simplified representation of reality and forms the basis for the mathematical modeling of contaminant fate and transport at the site. The CSM should therefore identify the...... most important site-specific features and processes that may affect the contaminant transport behavior at the site. However, the development of a CSM will always be associated with uncertainties due to limited data and lack of understanding of the site conditions. CSM uncertainty is often found to be a...

  20. Modeling and preliminary assessment of crude oil contaminated soil in Ogoni (Nigeria)

    Energy Technology Data Exchange (ETDEWEB)

    Thiergaertner, Hannes [Free Univ. Berlin (Germany). Faculty of Geosciences; Holtzmann, Kay

    2014-07-01

    In 2010, a severe contamination of soil and groundwater caused by the production and transportation of crude oil were detected in the Ogoni area, Federal Republic of Nigeria. A linear correlation between aliphatics and aromatics and the missing link between the degree of contamination and the depth of the soil samples indicate incomplete earlier remediation activities. 665 analyzed samples were mathematically reduced to 28 contamination patterns that can be distinguished by type and degree of pollution, environmentally assessed and visualized by a quasi 3-D model. Case studies taken from the Local Government Areas Eleme, Gokana, Khana, and Tai show the methodology and results.

  1. Modeling and preliminary assessment of crude oil contaminated soil in Ogoni (Nigeria)

    International Nuclear Information System (INIS)

    In 2010, a severe contamination of soil and groundwater caused by the production and transportation of crude oil were detected in the Ogoni area, Federal Republic of Nigeria. A linear correlation between aliphatics and aromatics and the missing link between the degree of contamination and the depth of the soil samples indicate incomplete earlier remediation activities. 665 analyzed samples were mathematically reduced to 28 contamination patterns that can be distinguished by type and degree of pollution, environmentally assessed and visualized by a quasi 3-D model. Case studies taken from the Local Government Areas Eleme, Gokana, Khana, and Tai show the methodology and results.

  2. Contamination and risk assessment of heavy metals in bottom sediments from Lake Valencia, Venezuela

    OpenAIRE

    González A; Palma M. G.; Ziegler K.; González E.; Álvarez M. A.

    2013-01-01

    The contamination and risk assessment of heavy metals in the bottom sediments of the Lake Valencia, Venezuela, was performed by determining the Enrichment Factor (EF), the Geoaccumulation Factor (Igeo), the availability of metals and the Risk Index Code (RAC). The sediments were anthropogenic ally enriched with Pb, Zn, Cu and Cr and classified as uncontaminated to moderately contaminated, with a medium risk of Zn, Co, Ni and Cr, and low risk of Cu, Pb and Cd. Analysis of correlations and PCA ...

  3. Assessment of combined electro–nanoremediation of molinate contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Helena I., E-mail: hrg@campus.fct.unl.pt [CENSE, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); CERNAS — Research Center for Natural Resources, Environment and Society, Escola Superior Agraria de Coimbra, Instituto Politecnico de Coimbra, Bencanta, 3045-601 Coimbra (Portugal); Fan, Guangping [CENSE, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences (ISSCAS), East Beijing Road, Nanjing 210008 (China); Mateus, Eduardo P. [CENSE, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Dias-Ferreira, Celia [CERNAS — Research Center for Natural Resources, Environment and Society, Escola Superior Agraria de Coimbra, Instituto Politecnico de Coimbra, Bencanta, 3045-601 Coimbra (Portugal); Ribeiro, Alexandra B. [CENSE, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2014-09-15

    Molinate is a pesticide widely used, both in space and time, for weed control in rice paddies. Due to its water solubility and affinity to organic matter, it is a contaminant of concern in ground and surface waters, soils and sediments. Previous works have showed that molinate can be removed from soils through electrokinetic (EK) remediation. In this work, molinate degradation by zero valent iron nanoparticles (nZVI) was tested in soils for the first time. Soil is a highly complex matrix, and pollutant partitioning between soil and water and its degradation rates in different matrices is quite challenging. A system combining nZVI and EK was also set up in order to study the nanoparticles and molinate transport, as well as molinate degradation. Results showed that molinate could be degraded by nZVI in soils, even though the process is more time demanding and degradation percentages are lower than in an aqueous solution. This shows the importance of testing contaminant degradation, not only in aqueous solutions, but also in the soil-sorbed fraction. It was also found that soil type was the most significant factor influencing iron and molinate transport. The main advantage of the simultaneous use of both methods is the molinate degradation instead of its accumulation in the catholyte. - Highlights: • Molinate is degraded in soil by zero valent iron nanoparticles (nZVI). • Higher contact time of nZVI with soil facilitates molinate degradation. • Soil type was the most significant factor influencing iron and molinate transport. • When using nZVI and EK molinate is not only transported to catholyte, but also degraded.

  4. Contaminants in the Greenland terrestrial and freshwater environment. National assessment

    International Nuclear Information System (INIS)

    The present report reviews the available information on heavy metals, persistent organic pollutants and radioactivity in the Greenland freshwater and terrestrial environments. Levels in lake sediments, soil, humus and organisms are presented, spatial and temporal trends are discussed and where possible also biological effects. Many of the contaminants that occur in the Greenland environment originate from distant sources outside of the region, and are transported to the Arctic via three major pathways - atmospheric, terrestrial/freshwater and marine. The main sources of pollution in Greenland is considered to be the industrialization of Eurasia. Pollutants are mainly. The organochlorine levels in Greenland char are typically in the low range compared to values reported from Canada. The Greenland sediment samples showed all organochlorine values below the detection limits of 0.1 μg/kg dry weight, thus being among the lowest contaminated sediments within the Arctic. The total content of PAH in the Greenland sediment samples ranged between 78-635 μ3 g/kg dry wight, with a geometric mean of 178 μg/kg, comparable to or lower than reported values from other arctic countries. The lowest concentrations of anthropogenic radionuclides in the Greenland terrestrial and freshwater environment are found in the northern parts of Greenland and the highest in the south western parts. The main source of anthropogenic radioactivity is nuclear weapons testing in the atmosphere and the fallout from this activity is closely related to the amounts of precipitation. The predominant foodchain in the Arctic with regard to transport of radiocaesium to man is: Lichen-reindeer-man. Although the doses from the terrestrial foodchain are 20 times higher than those received from the marine foodchain, they are not considered to be of any relevance for the human health in Greenland. 4 appendices contain experimental results. (EG)

  5. Assessment of combined electro–nanoremediation of molinate contaminated soil

    International Nuclear Information System (INIS)

    Molinate is a pesticide widely used, both in space and time, for weed control in rice paddies. Due to its water solubility and affinity to organic matter, it is a contaminant of concern in ground and surface waters, soils and sediments. Previous works have showed that molinate can be removed from soils through electrokinetic (EK) remediation. In this work, molinate degradation by zero valent iron nanoparticles (nZVI) was tested in soils for the first time. Soil is a highly complex matrix, and pollutant partitioning between soil and water and its degradation rates in different matrices is quite challenging. A system combining nZVI and EK was also set up in order to study the nanoparticles and molinate transport, as well as molinate degradation. Results showed that molinate could be degraded by nZVI in soils, even though the process is more time demanding and degradation percentages are lower than in an aqueous solution. This shows the importance of testing contaminant degradation, not only in aqueous solutions, but also in the soil-sorbed fraction. It was also found that soil type was the most significant factor influencing iron and molinate transport. The main advantage of the simultaneous use of both methods is the molinate degradation instead of its accumulation in the catholyte. - Highlights: • Molinate is degraded in soil by zero valent iron nanoparticles (nZVI). • Higher contact time of nZVI with soil facilitates molinate degradation. • Soil type was the most significant factor influencing iron and molinate transport. • When using nZVI and EK molinate is not only transported to catholyte, but also degraded

  6. Ecological Risk Assessment of a Metal-Contaminated Area in the Tropics. Tier II: Detailed Assessment.

    Science.gov (United States)

    Niemeyer, Júlia Carina; Moreira-Santos, Matilde; Ribeiro, Rui; Rutgers, Michiel; Nogueira, Marco Antonio; da Silva, Eduardo Mendes; Sousa, José Paulo

    2015-01-01

    This study presents data on the detailed evaluation (tier 2) of a site-specific ecological risk assessment (ssERA) in a former smelter area contaminated with metals (Santo Amaro, Bahia, Brazil). Combining information from three lines of evidence (LoE), chemical (ChemLoE), ecotoxicological (EcotoxLoE) and ecological (EcoLoE), in the Triad approach, integrated risk values were calculated to rank sites and confirm the potential risk disclosed with tier 1. Risk values were calculated for the habitat and for the retention functions in each sampling point. Habitat function included the ChemLoE calculated from total metal concentrations. The EcotoxLoE was based on reproduction tests with terrestrial invertebrates (Folsomia candida, Enchytraeus crypticus, Eisenia andrei), shoot length and plant biomass (Avena sativa, Brassica rapa). For the EcoLoE, ecological parameters (microbial parameters, soil invertebrate community, litter breakdown) were used to derive risk values. Retention function included the ChemLoE, calculated from extractable metal concentrations, and the EcotoxLoE based on eluate tests with aquatic organisms (Daphnia magna reproduction and Pseudokirchneriella subcapitata growth). Results related to the habitat function indicated that the metal residues are sufficient to cause risk to biota, while the low metal levels in extracts and the general lack of toxicity in aquatic tests indicated a high soil retention capacity in most sampling points. Integrated risk of tier 2 showed the same trend of tier 1, suggesting the need to proceed with remediation actions. The high risk levels were related to direct toxicity to organisms and indirect effects, such as failure in the establishment of vegetation and the consequent loss of habitat quality for microorganisms and soil fauna. This study shed some light on the selection of tools for the tier 2 of an ssERA in tropical metal-contaminated sites, focusing on ecological receptors at risk and using available chemical

  7. Ecological Risk Assessment of a Metal-Contaminated Area in the Tropics. Tier II: Detailed Assessment.

    Directory of Open Access Journals (Sweden)

    Júlia Carina Niemeyer

    Full Text Available This study presents data on the detailed evaluation (tier 2 of a site-specific ecological risk assessment (ssERA in a former smelter area contaminated with metals (Santo Amaro, Bahia, Brazil. Combining information from three lines of evidence (LoE, chemical (ChemLoE, ecotoxicological (EcotoxLoE and ecological (EcoLoE, in the Triad approach, integrated risk values were calculated to rank sites and confirm the potential risk disclosed with tier 1. Risk values were calculated for the habitat and for the retention functions in each sampling point. Habitat function included the ChemLoE calculated from total metal concentrations. The EcotoxLoE was based on reproduction tests with terrestrial invertebrates (Folsomia candida, Enchytraeus crypticus, Eisenia andrei, shoot length and plant biomass (Avena sativa, Brassica rapa. For the EcoLoE, ecological parameters (microbial parameters, soil invertebrate community, litter breakdown were used to derive risk values. Retention function included the ChemLoE, calculated from extractable metal concentrations, and the EcotoxLoE based on eluate tests with aquatic organisms (Daphnia magna reproduction and Pseudokirchneriella subcapitata growth. Results related to the habitat function indicated that the metal residues are sufficient to cause risk to biota, while the low metal levels in extracts and the general lack of toxicity in aquatic tests indicated a high soil retention capacity in most sampling points. Integrated risk of tier 2 showed the same trend of tier 1, suggesting the need to proceed with remediation actions. The high risk levels were related to direct toxicity to organisms and indirect effects, such as failure in the establishment of vegetation and the consequent loss of habitat quality for microorganisms and soil fauna. This study shed some light on the selection of tools for the tier 2 of an ssERA in tropical metal-contaminated sites, focusing on ecological receptors at risk and using available

  8. On-line sensor monitoring for chemical contaminant attenuation during UV/H2O2 advanced oxidation process.

    Science.gov (United States)

    Yu, Hye-Weon; Anumol, Tarun; Park, Minkyu; Pepper, Ian; Scheideler, Jens; Snyder, Shane A

    2015-09-15

    A combination of surrogate parameters and indicator compounds were measured to predict the removal efficiency of trace organic compounds (TOrCs) using low pressure (LP)-UV/H2O2 advanced oxidation process (AOP), engaged with online sensor-based monitoring system. Thirty-nine TOrCs were evaluated in two distinct secondary wastewater effluents in terms of estimated photochemical reactivity, as a function of the rate constants of UV direct photolysis (kUV) and hydroxyl radical (OH) oxidation (kOH). The selected eighteen TOrCs were classified into three groups that served as indicator compounds: Group 1 for photo-susceptible TOrCs but with minor degradation by OH oxidation (diclofenac, fluoxetine, iohexol, iopamidol, iopromide, simazine and sulfamethoxazole); Group 2 for TOrCs susceptible to both direct photolysis and OH oxidation (benzotriazole, diphenhydramine, ibuprofen, naproxen and sucralose); and Group 3 for photo-resistant TOrCs showing dominant degradation by OH oxidation (atenolol, carbamazepine, DEET, gemfibrozil, primidone and trimethoprim). The results indicate that TOC (optical-based measurement), UVA254 or UVT254 (UV absorbance or transmittance at 254 nm), and total fluorescence can all be used as suitable on-line organic surrogate parameters to predict the attenuation of TOrCs. Furthermore, the automated real-time monitoring via on-line surrogate sensors and equipped with the developed degradation profiles between sensor response and a group of TOrCs removal can provide a diagnostic tool for process control during advanced treatment of reclaimed waters. PMID:26074188

  9. Radiological risk assessment for radioactive contamination at landfill site

    International Nuclear Information System (INIS)

    A limited-scope preliminary assessment of radiological risk has been conducted for a landfill site where radioactive residues resulting from past uranium ore processing operations are present. Potential radiation doses to an individual under different scenarios have been predicted using the RESRAD computer code. The assessment provides useful input to the remedial action planning for the site that is currently underway. 7 refs., 6 figs., 3 tabs

  10. Guidance for treatment of variability and uncertainty in ecological risk assessments of contaminated sites

    International Nuclear Information System (INIS)

    Uncertainty is a seemingly simple concept that has caused great confusion and conflict in the field of risk assessment. This report offers guidance for the analysis and presentation of variability and uncertainty in ecological risk assessments, an important issue in the remedial investigation and feasibility study processes. This report discusses concepts of probability in terms of variance and uncertainty, describes how these concepts differ in ecological risk assessment from human health risk assessment, and describes probabilistic aspects of specific ecological risk assessment techniques. The report ends with 17 points to consider in performing an uncertainty analysis for an ecological risk assessment of a contaminated site

  11. Guidance for treatment of variability and uncertainty in ecological risk assessments of contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-06-01

    Uncertainty is a seemingly simple concept that has caused great confusion and conflict in the field of risk assessment. This report offers guidance for the analysis and presentation of variability and uncertainty in ecological risk assessments, an important issue in the remedial investigation and feasibility study processes. This report discusses concepts of probability in terms of variance and uncertainty, describes how these concepts differ in ecological risk assessment from human health risk assessment, and describes probabilistic aspects of specific ecological risk assessment techniques. The report ends with 17 points to consider in performing an uncertainty analysis for an ecological risk assessment of a contaminated site.

  12. A Bayesian belief network approach for assessing uncertainty in conceptual site models at contaminated sites

    Science.gov (United States)

    Thomsen, Nanna I.; Binning, Philip J.; McKnight, Ursula S.; Tuxen, Nina; Bjerg, Poul L.; Troldborg, Mads

    2016-05-01

    A key component in risk assessment of contaminated sites is in the formulation of a conceptual site model (CSM). A CSM is a simplified representation of reality and forms the basis for the mathematical modeling of contaminant fate and transport at the site. The CSM should therefore identify the most important site-specific features and processes that may affect the contaminant transport behavior at the site. However, the development of a CSM will always be associated with uncertainties due to limited data and lack of understanding of the site conditions. CSM uncertainty is often found to be a major source of model error and it should therefore be accounted for when evaluating uncertainties in risk assessments. We present a Bayesian belief network (BBN) approach for constructing CSMs and assessing their uncertainty at contaminated sites. BBNs are graphical probabilistic models that are effective for integrating quantitative and qualitative information, and thus can strengthen decisions when empirical data are lacking. The proposed BBN approach facilitates a systematic construction of multiple CSMs, and then determines the belief in each CSM using a variety of data types and/or expert opinion at different knowledge levels. The developed BBNs combine data from desktop studies and initial site investigations with expert opinion to assess which of the CSMs are more likely to reflect the actual site conditions. The method is demonstrated on a Danish field site, contaminated with chlorinated ethenes. Four different CSMs are developed by combining two contaminant source zone interpretations (presence or absence of a separate phase contamination) and two geological interpretations (fractured or unfractured clay till). The beliefs in each of the CSMs are assessed sequentially based on data from three investigation stages (a screening investigation, a more detailed investigation, and an expert consultation) to demonstrate that the belief can be updated as more information

  13. Dispersal and attenuation of trace contaminants downstream of the Ajka bauxite residue (red mud) depository failure, Hungary.

    Science.gov (United States)

    Mayes, William M; Jarvis, Adam P; Burke, Ian T; Walton, Melanie; Feigl, Viktória; Klebercz, Orsolya; Gruiz, Katalin

    2011-06-15

    This paper identifies the spatial extent of bauxite processing residue (red mud)-derived contaminants and modes of transport within the Marcal and Rába river systems after the dike failure at Ajka, western Hungary. The geochemical signature of the red mud is apparent throughout the 3076 km² Marcal system principally with elevated Al, V, As, and Mo. Elevated concentrations of Cr, Ga, and Ni are also observed within 2 km of the source areas in aqueous and particulate phases where hyperalkalinity (pH waters (e.g., V, As) and fluvial sediments (As, Cr, Ni, V), the spatial extent of these is limited to the Torna Creek and part of the upper Marcal. Source samples show a bimodal particle size distribution (peaks at 0.7 and 1.3 μm) which lends the material to ready fluvial transport. Where elevated concentrations are found in fluvial sediments, sequential extraction suggests the bulk of the As, Cr, Ni, and V are associated with residual (aqua-regia/HF digest) phases and unlikely to be mobile in the environment. However, at some depositional hotspots, association of As, Cr, and V with weak acid-extractable phases is observed. PMID:21591764

  14. Assessment of Hexavalent Chromium Natural Attenuation for the Hanford Site 100 Area

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Szecsody, James E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, Nikolla P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sahajpal, Rahul [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhong, Lirong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lawter, Amanda R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lee, Brady D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-09-01

    Hexavalent chromium (Cr(VI)) plumes are present in the 100 Area at the Hanford Site. Remediation efforts are under way with objectives of restoring the groundwater to meet the drinking-water standard (48 µg/L) and protecting the Columbia River by ensuring that discharge of groundwater to the river is below the surface-water quality standard (10 µg/L). Current remedies include application of Pump-and-Treat (P&T) at the 100-D, 100-H, and 100-K Areas and Monitored Natural Attenuation (MNA) at the 100-F/IU Area. Remedy selection is still under way at the other 100 Areas. Additional information about the natural attenuation processes for Cr(VI) is important in all of these cases. In this study, laboratory experiments were conducted to demonstrate and quantify natural attenuation mechanisms using 100 Area sediments and groundwater conditions.

  15. The treatment of sorption and retardation in the assessment of geological barriers to contaminant transport

    International Nuclear Information System (INIS)

    The approaches used in long-term performance assessments to determine the impact of sorption in the geosphere on retarding the movement of radioactive contaminants have been reviewed. A comparison is made between the approaches used in the 1994 assessment of the Whiteshell Research Area in Canada and in similar assessments conducted in other countries. The long-term performance assessments reviewed were the AECL-EIS, the TVO-92 assessment conducted in Finland, the PNC-H3 project from Japan , the SKI Project-90 and SKB-91 assessments performed in Sweden, the Kristallin-1 assessment done in Switzerland, and the NIREX-95 assessment performed in the United Kingdom. In each of these assessments, the effect of sorption in the geosphere on contaminant transport was assessed using the 'Kd concept'. The sorption data were selected to reflect the anticipated effects of the reference geochemical conditions of the site being assessed. A number of approaches were taken to account for the uncertainty in the values selected for the sorption coefficients. Contaminant transport was modelled using a continuous porous medium approach or a dual-porosity approach, with the latter being more widely used. In both approaches, the retardation of contaminant transport due to sorption on the host solid is described by a retardation factor. In the present report, sorption values used in the assessments were compared and differences between the values selected for similar materials and geochemical conditions were noted, particularly for the redoxsensitive elements. A comparison of retardation factors required the introduction of a 'utilization factor' into the retardation equation to account for the effects of matrix diffusion on retardation. The comparison illustrated the impact of time dependence on retardation in the matrix diffusion approach vis-a-vis the time-independent retardation approach used in the AECL-EIS. (author)

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

    DEFF Research Database (Denmark)

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

    2011-01-01

    -generic assessments poorly reflect the fate of frequent soil contaminants such as chloroethenes as they exclude the groundwater compartment and assume that the main part escapes to the atmosphere. Another important limitation of the generic impact assessment models is that they do not include the formation of......The environmental impacts from remediation can be divided into primary and secondary impacts. Primary impacts cover the local impacts associated with the on-site contamination, whereas the secondary impacts are impacts on the local, regional and global scale generated by the remediation activities...... impacts have typically been assessed using site-generic characterization models representing a continental scale and excluding the groundwater compartment. Soil contaminants have therefore generally been assigned as emissions to surface soil or surface water compartments. However, such site...

  17. Geophysical assessment of salt and hydrocarbon contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Bentley, L.R.; Hayley, K.; Gharibi, M.; Forte, S.A.; MacDonald, J. [Calgary Univ., AB (Canada). Dept. of Geoscience; Headley, J. [Environment Canada, Saskatoon, SK (Canada). Water Science and Technology Directorate

    2007-07-01

    This presentation described a 3 year study at an active remediation site where a pipeline had leaked hydrocarbons. The objective was to develop practical protocols for evaluating the distribution and evolution of salt and hydrocarbons in soils and groundwater. The geometry of the contaminated area was determined in detail in order to improve the remediation design and to monitor the remediation process. Problem areas were identified for early intervention. Two-dimensional resistivity imaging was used to estimate salt concentrations. The changing environmental conditions required corrections for differences in temperature and soil moisture conditions. This presentation summarized the field acquisition campaigns from July 2004 to Oct 2006. The redistribution of salt was observed using time-lapse electric resistivity imaging. It was determined that auxiliary data and corrections for varying environmental conditions are necessary and that 3-D surveys are often needed for quantitative estimates. It was concluded that the uneven leaching distributions beneath depressions may indicate a need for occasional recontouring. tabs., figs.

  18. Assessment Of Depleted Uranium Contamination In Selective IRAQI Soils

    International Nuclear Information System (INIS)

    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

  19. Preventing intentional food contamination: a survey to assess restaurant preparedness.

    Science.gov (United States)

    Xirasagar, Sudha; Kanwat, C P; Qu, Haiyan; Smith, Lillian U; Patterson, Nathaniel J; Shewchuk, Richard M

    2010-01-01

    In the age of preparedness, public health agencies are concerned with intentional acts of food contamination in restaurants, in addition to food safety. Food safety consists of applying standard norms of practice and infrastructure, which, if violated, cause food-borne illness. In contrast, food defense requires an institutionalized mindset of informed alertness to unusual variations from the norms, combined with preemptive practices best suited to each restaurant. Therefore, while food safety lends itself to regulation to ensure standard practices, food defense is best served by advisory guidelines for autonomous application, preserving the restaurant industry's core values of hospitality and customer service. To address this challenge, public health agencies need survey tools that can yield action-relevant data on the knowledge and practice gaps in food defense preparedness and on educational messages and support services to be developed for maximum impact potential. This article presents a mail survey instrument, developed using qualitative research to ensure content and face validity. Instrument development involved drafting the survey on the basis of expert consultations, validating its content by using focus groups (representing all restaurant categories and geographic regions), and ensuring face validity through cognitive interviews. The resulting survey remains sensitive to the hospitality industry while encompassing all vulnerable points. PMID:20520363

  20. Economic assessment of losses caused by contamination of soil resources within effective their use

    Directory of Open Access Journals (Sweden)

    Anatoliy Kucher

    2015-05-01

    Full Text Available The article analyzes the current state of soil contamination in Ukraine and valid method of determining loss from contamination. Losses from soil contamination can be direct and indirect ones. Direct losses, on the total, characterize reduction of consumer’s cost of land as a tool and object of labour. Indirect losses are predefined by decline in yield of agricultural crops on contaminated soils, worsened quality of products, increase in unit-cost of contaminated produce through increased per cent of semi-fixed expenditures due to reduced crop productivity. A scientific and methodical approach to the assessment of internal ecological and economic losses of agricultural enterprises from soil contamination isgrounded. Basic criteria to determinate internal ecological and economical losses from soils’ contamination are losses of profit whose obtaining is the main goal of the enterprise performance in marketing conditions. Major constituents of internal ecological and economical loss incurred by an agrarian enterprise are: losses of profit due to obtaining less products than expected, because of shortage of crop yield through contamination of soils; losses of profit due to deteriorated qualityof agricultural produce through contamination of soils; losses of enterprise profits due to increase of product unit-cost through declined labour productivity, predefined by reduction of crop-yield productivity at the same rates of semi-fixed expenditures. Such complex science & methodical approach to determination of loss on microeconomical level can help one completely identify losses of agricultural production, caused bycontamination of soils and strengthening one’s attention hereto, possibly, increasing responsibility of contaminants for quality of soils and products obtained hereof.

  1. Natural arsenic attenuation via metal arsenate precipitation in soils contaminated with metallurgical wastes: III. Adsorption versus precipitation in clean As(V)/goethite/Pb(II)/carbonate systems

    International Nuclear Information System (INIS)

    Soil contamination with As and potentially harmful metals is a widespread problem around the world especially from mining and metallurgical wastes, which release substantial amounts of these elements to the environment in potentially mobile species. Recently, it has been found that in various Mexican soils contaminated with these types of wastes, arsenate is not in the form of sorbed species on Fe oxides present in the soils, as generally reported in the literature, but in the form of very insoluble compounds such as Pb, Cu and Ca arsenates. Here a thermodynamic model is applied and validated with the results from wet chemical experiments to determine the fundamental geochemical conditions governing the mobility of As in the presence of Pb. For this purpose, a relatively simple but fundamental system of goethite (α-FeOOH)/As(V)/Pb(II)/carbonate was defined as a function of the As(V)/Fe(III) ratio, in a pH range of 5–10. The speciation model included the simultaneous inclusion of triple layer surface complexation and arsenate precipitation equilibria. The model predicts that from very low total As(V)/Fe(III) molar ratios (0.012 at pH 7) the precipitation mechanism significantly influences the attenuation of As(V), and rapidly becomes the dominant process over the adsorption mechanism. Model results identify the quantitative conditions of predominance for each mechanism and describe the transition conditions in which relatively large fractions of adsorbed, precipitated and dissolved As(V) species prevail. Experimental measurements at selected As(V)/Fe(III) ratios and pH confirmed the predictions and validated the coupled thermodynamic model utilized.

  2. Validation of an integrative methodology to assess and monitor reductive dechlorination of chlorinated ethenes in contaminated aquifers

    Directory of Open Access Journals (Sweden)

    Sonia-Estelle eTarnawski

    2016-02-01

    Full Text Available Bioremediation of tetra-and trichloroethene-contaminated aquifers is frequently hampered due to incomplete dechlorination to the more toxic dichloroethene (DCE and vinyl chloride (VC, indicating insufficient knowledge about the biological mechanisms related to aquifer functioning. A methodology based on the joint analysis of geochemical and microbiological datasets was developed to assess the presence of the biochemical potential for complete reductive dechlorination to harmless ethene and to explain the reasons for which degradation often stalls at the more toxic intermediates. This methodology is composed of three successive steps, with i the acquisition of geochemical data including chlorinated ethenes, ii the detailed analysis of the bacterial community structures as well as the biochemical potential for complete dechlorination using microcosms and molecular detection of organohalide-respiring bacteria and key reductive dehalogenases, and iii a statistical Multiple Factor Analysis combining the above mentioned abiotic and biotic variables in a functional modelling of the contaminated aquifer. The methodology was validated by analyzing two chlorinated ethenes-contaminated sites. Results from the first site showed that the full biochemical potential for ethene production was present in situ. However, redox potential was overall too high and locally manganese reduction out-competed chlorinated ethenes reduction, explaining the reasons for the local accumulation of DCE and VC to a lesser extent. The second contaminated aquifer was under bioremediation by successive cheese whey injections. Analysis demonstrated that cheese whey additions led to increasingly reduced redox conditions and that hampered reductive dechlorination was not due to competition with other anaerobic respiration processes. Complete reductive dechlorination to ethene was preferentially occurring under methanogenic conditions. DCE and VC accumulation was probably induced first

  3. A tiered assessment framework to evaluate human health risk of contaminated sediment.

    Science.gov (United States)

    Greenfield, Ben K; Melwani, Aroon R; Bay, Steven M

    2015-07-01

    For sediment contaminated with bioaccumulative pollutants (e.g., PCBs and organochorine pesticides), human consumption of seafood that contain bioaccumulated sediment-derived contaminants is a well-established exposure pathway. Historically, regulation and management of this bioaccumulation pathway has focused on site-specific risk assessment. The state of California (United States) is supporting the development of a consistent and quantitative sediment assessment framework to aid in interpreting a narrative objective to protect human health. The conceptual basis of this framework focuses on 2 key questions: 1) do observed pollutant concentrations in seafood from a given site pose unacceptable health risks to human consumers? and 2) is sediment contamination at a site a significant contributor to seafood contamination? The first question is evaluated by interpreting seafood tissue concentrations at the site, based on health risk calculations. The second question is evaluated by interpreting site-specific sediment chemistry data using a food web bioaccumulation model. The assessment framework includes 3 tiers (screening assessment, site assessment, and refined site assessment), which enables the assessment to match variations in data availability, site complexity, and study objectives. The second and third tiers use a stochastic simulation approach, incorporating information on variability and uncertainty of key parameters, such as seafood contaminant concentration and consumption rate by humans. The framework incorporates site-specific values for sensitive parameters and statewide values for difficult to obtain or less sensitive parameters. The proposed approach advances risk assessment policy by incorporating local data into a consistent region-wide problem formulation, applying best available science in a streamlined fashion. PMID:25641876

  4. Equilibrium sampling for a thermodynamic assessment of contaminated sediments

    DEFF Research Database (Denmark)

    of the biota relative to the sediment. Furthermore, concentrations in lipid at thermodynamic equilibrium with sediment (Clip?Sed) can be calculated via lipid/silicone partition ratios CSil × KLip:Sil, which has been done in studies with limnic, river and marine sediments. The data can then be......) govern diffusive uptake and partitioning. Equilibrium sampling of sediment was introduced 15 years ago to measure Cfree, and it has since developed into a straightforward, precise and sensitive approach for determining Cfree and other exposure parameters that allow for thermodynamic assessment of......) toxicity. This overview lecture will focus at the latest developments in equilibrium sampling concepts and methods. Further, we will explain how these approaches can provide a new basis for a thermodynamic assessment of polluted sediments....

  5. ASSESSMENT OF MICROBIAL CONTAMINATION IN COMMERCIAL HERBAL ORAL MEDICINAL LIQUIDS.

    OpenAIRE

    Chitrarekha Kulkarni

    2010-01-01

    Worldwide demand for therapeutic herbal and neutraceutical preparations has increased greatly in past few years. In India, like other pharmaceutical preparations, there is a need to put strict regulations over the microbial quality of such preparations since they are consumed internally and safety is of prime concern. In this work we have focused on assessing the microbial quality of few marketed herbal liquid oral preparations. These preparations were procured from retail pharmacy outlets an...

  6. Assessment of phytoremediation as an in-situ technique for cleaning oil-contaminated sites

    International Nuclear Information System (INIS)

    Literature on examples of phytoremediation techniques used in the in-situ remediation of soils contaminated by petroleum hydrocarbons is reviewed. The review includes discussion of the key mechanisms involved in each case, benefits, limitations and costs compared to alternative approaches, including natural attenuation, engineering and bioremediation. Review of the literature led to the conclusion that phytoremediation is an effective method for degrading and containing petroleum hydrocarbons in soil, and confirmed the ability of plants to transfer volatile petroleum hydrocarbons, such as napthalene, from the soil to the atmosphere via transpiration. The primary loss mechanism for the degradation of petroleum hydrocarbons appears to be microorganisms in the rhizosphere of plants. The available information also suggests that plants may degrade petroleum hydrocarbons directly, although the indirect role played by plants is far more common. These roles include supplying root exudates for microbial use, releasing root-associated enzymes that degrade contaminants in the soil, and altering soil to promote phytoremediation. BTEX compounds are most easily amenable to phytoremediation; large and lipophilic compounds such as four or five-ring polyaromatic hydrocarbons are more difficult to remediate. The limited information available suggests that phytoremediation is slightly less expensive than bioremediation, and several order of magnitude less than engineering techniques. In general, phytoremediation is faster than natural attenuation, but typically slower than engineering and bioremediation. On the other hand, it is less disruptive to the site than ex-situ engineering and bioremediation that involve excavation efforts. Phytoremediation is most effective with shallow contamination. Preliminary screenings indicate that there are several plant species, native and introduced, that may be used with some success for phytoremediation in the Prairie and Boreal Plains ecozones

  7. Assessment of the implications of radium contamination of Dalgety Bay beach and foreshore

    International Nuclear Information System (INIS)

    Radium 226 contamination was identified at Dalgety Bay in Scotland in 1990 as a consequence of routine surveying. It is assumed that the contamination originated from the disposal of luminised instruments from a former wartime airbase. This report describes work carried out to assess the implications of the contamination. It covers: a survey of beach use; a field survey of the extent of the contamination, laboratory studies of the chemical content of samples from the area and the leaching of radioactive components; physical and biological perturbation of the sediment; the potential risk to humans. The survey showed there to be only a low risk to the public and that access to the beach does not need to be restricted. It is recommended, however, that an intensive survey/decontamination exercise should be mounted with subsequent systematic monitoring. (U.K.)

  8. Baseline ecological risk assessment and remediation alternatives for a hydrocarbon-contaminated estuarine wetland

    International Nuclear Information System (INIS)

    Prior to a property transaction, the groundwater at an industrial refinery site in New Jersey was found to be contaminated with a variety of petroleum-based organic compounds. The highly built-up site included an on-site estuarine wetland and was located in a developed, industrialized area near ecologically important estuarine marshes. A preliminary ecological risk assessment was developed on the basis of available data on site contamination and ecological resources. The onsite wetland and its user fauna were identified as the sensitive receptors of concern and the primary contaminant pathways wee identified. The ecological significance of the contamination was assessed with regard to the onsite wetland and in the context of its position within the landscape and surrounding land uses. The wetland exhibited a combination of impact and vitality, i.e., there were clearly visible signs of contaminant impact as well as a relatively complex and abundant food web. Because of its position within the developed landscape, the onsite wetland appeared to function as a refugium for wildlife despite the level of disturbance. The feasibility of achieving regulatory compliance through natural remediation was also examined with respect to the findings of the risk assessment and the resultant conclusions are discussed

  9. Assessing exposures and risks in heterogeneously contaminated areas: A simulation approach

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) is responsible for cleanup activities at a number of facilities under its Environmental Restoration and Waste Management Program. The major goals of this program are to eliminate potential hazards to human health and the environment that are associated with contamination of these sites and, to the extent possible, make surplus real property available for other uses. The assessment of potential baseline health risks and ecological impacts associated with a contaminated site is an important component of the remedial investigation/feasibility study (RI/FS) process required at all Superfund sites. The purpose of this paper is to describe one phase of the baseline assessment, i.e., the characterization of human health risks associated with exposure to chemical contaminants in air and on interior building surfaces at a contaminated site. The model combines data on human activity patterns in a particular microenvironment within a building with contaminant concentrations in that microenvironment to calculate personal exposure profiles and risks within the building. The results of the building assessment are presented as probability distributions functions and cumulative distribution functions, which show the variability and uncertainty in the risk estimates. 23 refs., 2 figs., 1 tab

  10. Multimedia contaminant environmental exposure assessment methodology as applied to Los Alamos, New Mexico

    International Nuclear Information System (INIS)

    The MCEA (Multimedia Contaminant Environmental Exposure Assessment) methodology assesses exposures to air, water, soil, and plants from contaminants released into the environment by simulating dominant mechanisms of contaminant migration and fate. The methodology encompasses five different pathways (i.e., atmospheric, terrestrial, overland, subsurface, and surface water) and combines them into a highly flexible tool. The flexibility of the MCEA methodology is demonstrated by encompassing two of the pathways (i.e., overland and surface water) into an effective tool for simulating the migration and fate of radionuclides released into the Los Alamos, New Mexico region. The study revealed that: (a) the 239Pu inventory in lower Los Alamos Canyon increased by approximately 1.1 times for the 50-y flood event; (b) the average contaminant 239Pu concentrations (i.e., weighted according to the depth of the respective bed layer) in lower Los Alamos Canyon for the 50-y flood event decreased by 5.4%; (c) approx. 27% of the total 239Pu contamination resuspended from the entire bed (based on the assumed cross sections) for the 50-y flood event originated from lower Pueblo Canyon; (d) an increase in the 239Pu contamination of the bed followed the general deposition patterns experienced by the sediment in Pueblo-lower Los Alamos Canyon; likewise, a decrease in the 239Pu contamination of the bed followed general sediment resuspension patterns in the canyon; (e) 55% of the 239Pu reaching the San Ildefonso Pueblo in lower Los Alamos Canyon originated from lower Los Alamos Canyon; and (f) 56% of the 239Pu contamination reaching the San Ildefonso Pueblo in lower Los Alamos Canyon was carried through towards the Rio Grande. 47 references, 41 figures, 29 tables

  11. Assessment of contaminant fate in catchments using a novel integrated hydrobiogeochemical-multimedia fate model.

    Science.gov (United States)

    Nizzetto, Luca; Butterfield, Dan; Futter, Martyn; Lin, Yan; Allan, Ian; Larssen, Thorjørn

    2016-02-15

    Models for pollution exposure assessment typically adopt an overly simplistic representation of geography, climate and biogeochemical processes. This strategy is unsatisfactory when high temporal resolution simulations for sub-regional spatial domains are performed, in which parameters defining scenarios can vary interdependently in space and time. This is, for example, the case when assessing the influence of biogeochemical processing on contaminant fate. Here we present INCA-Contaminants, the Integrated Catchments model for Contaminants; a new model that simultaneously and realistically solves mass balances of water, carbon, sediments and contaminants in the soil-stream-sediment system of catchments and their river networks as a function of climate, land use/management and contaminant properties. When forced with realistic climate and contaminant input data, the model was able to predict polychlorinated biphenyls (PCBs) concentrations in multiple segments of a river network in a complex landscape. We analyzed model output sensitivity to a number of hydro-biogeochemical parameters. The rate of soil organic matter mineralization was the most sensitive parameter controlling PCBs levels in river water, supporting the hypothesis that organic matter turnover rates will influence re-mobilization of previously deposited PCBs which had accumulated in soil organic matrix. The model was also used to project the long term fate of PCB 101 under two climate scenarios. Catchment diffuse run-off and riverine transport were the major pathways of contaminant re-mobilization. Simulations show that during the next decade the investigated boreal catchment will shift from being a net atmospheric PCB sink to a net source for air and water, with future climate perturbation having little influence on this trend. Our results highlight the importance of using credible hydro-biogeochemical simulations when modeling the fate of hydrophobic contaminants. PMID:26674684

  12. Opportunities and challenges of integrating ecological restoration into assessment and management of contaminated ecosystems.

    Science.gov (United States)

    Hull, Ruth N; Luoma, Samuel N; Bayne, Bruce A; Iliff, John; Larkin, Daniel J; Paschke, Mark W; Victor, Sasha L; Ward, Sara E

    2016-04-01

    Ecosystem restoration planning near the beginning of the site assessment and management process ("early integration") involves consideration of restoration goals from the outset in developing solutions for contaminated ecosystems. There are limitations to integration that stem from institutional barriers, few successful precedents, and limited availability of guidance. Challenges occur in integrating expertise from various disciplines and multiple, sometimes divergent interests and goals. The more complex process can result in timing, capacity, communication, and collaboration challenges. On the other hand, integrating the 2 approaches presents new and creative opportunities. For example, integration allows early planning for expanding ecosystem services on or near contaminated lands or waters that might otherwise have been unaddressed by remediation alone. Integrated plans can explicitly pursue ecosystem services that have market value, which can add to funds for long-term monitoring and management. Early integration presents opportunities for improved and productive collaboration and coordination between ecosystem restoration and contaminant assessment and management. Examples exist where early integration facilitates liability resolution and generates positive public relations. Restoration planning and implementation before the completion of the contaminated site assessment, remediation, or management process ("early restoration") can facilitate coordination with offsite restoration options and a regional approach to restoration of contaminated environments. Integration of performance monitoring, for both remedial and restoration actions, can save resources and expand the interpretive power of results. Early integration may aid experimentation, which may be more feasible on contaminated lands than in many other situations. The potential application of concepts and tools from adaptive management is discussed as a way of avoiding pitfalls and achieving benefits in

  13. Levels and risk assessment of chemical contaminants in byproducts for animal feed in Denmark.

    Science.gov (United States)

    Mortensen, Alicja; Granby, Kit; Eriksen, Folmer D; Cederberg, Tommy Licht; Friis-Wandall, Søren; Simonsen, Yvonne; Broesbøl-Jensen, Birgitte; Bonnichsen, Rikke

    2014-01-01

    With aim to provide information on chemical contaminants in byproducts in animal feed, the data from an official control by the Danish Plant Directorate during 1998-2009, were reviewed and several samples of citrus pulp and dried distillers grains with solubles (DDGS) were additionally collected for analysis and risk assessment. The levels of contaminants in the samples from the official control were below maximum limits from EU regulations with only a few exceptions in the following groups; dioxins and dioxin-like polychlorobiphenyls (PCBs) in fish-containing byproducts and dioxins in vegetable and animal fat, hydrogen cyanide in linseed, and cadmium in sunflowers. The levels of pesticides and mycotoxins in the additionally collected samples were below maximum limits. Enniatin B (ENN B) was present in all DDGS samples. The hypothetical cases of carry-over of contamination from these byproducts were designed assuming total absorption and accumulation of the ingested contaminant in meat and milk and high exposure (a byproduct formed 15-20% of the feed ration depending on the species). The risk assessment was refined based on literature data on metabolism in relevant animal species. Risk assessment of contaminants in byproducts is generally based on a worst-case approach, as data on carry-over of a contaminant are sparse. This may lead to erroneous estimation of health hazards. The presence of ENN B in all samples of DDGS indicates that potential impact of this emerging mycotoxin on feed and food safety deserves attention. A challenge for the future is to fill up gaps in toxicological databases and improve models for carry-over of contaminants. PMID:25190554

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

    International Nuclear Information System (INIS)

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

  15. Assessing the Impact of Source-Zone Remediation Efforts at the Contaminant-Plume Scale Through Analysis of Contaminant Mass Discharge

    OpenAIRE

    Brusseau, M.L.; Hatton, J.; DiGuiseppi, W.

    2011-01-01

    The long-term impact of source-zone remediation efforts was assessed for a large site contaminated by trichloroethene. The impact of the remediation efforts (soil vapor extraction and in-situ chemical oxidation) was assessed through analysis of plume-scale contaminant mass discharge, which was measured using a high-resolution data set obtained from 23 years of operation of a large pump-and-treat system. The initial contaminant mass discharge peaked at approximately 7 kg/d, and then declined t...

  16. The rationale for simple approaches for sustainability assessment and management in contaminated land practice.

    Science.gov (United States)

    Bardos, R Paul; Bone, Brian D; Boyle, Richard; Evans, Frank; Harries, Nicola D; Howard, Trevor; Smith, Jonathan W N

    2016-09-01

    The scale of land-contamination problems, and of the responses to them, makes achieving sustainability in contaminated land remediation an important objective. The Sustainable Remediation Forum in the UK (SuRF-UK) was established in 2007 to support more sustainable remediation practice in the UK. The current international interest in 'sustainable remediation' has achieved a fairly rapid consensus on concepts, descriptions and definitions for sustainable remediation, which are now being incorporated into an ISO standard. However the sustainability assessment methods being used remain diverse with a range of (mainly) semi-quantitative and quantitative approaches and tools developed, or in development. Sustainability assessment is site specific and subjective. It depends on the inclusion of a wide range of considerations across different stakeholder perspectives. Taking a tiered approach to sustainability assessment offers important advantages, starting from a qualitative assessment and moving through to semi-quantitative and quantitative assessments on an 'as required' basis only. It is also clear that there are a number of 'easy wins' that could improve performance against sustainability criteria right across the site management process. SuRF-UK has provided a checklist of 'sustainable management practices' that describes some of these. This paper provides the rationale for, and an outline of, and recently published SuRF-UK guidance on preparing for and framing sustainability assessments; carrying out qualitative sustainability assessment; and simple good management practices to improve sustainability across contaminated land management activities. PMID:26765509

  17. Contaminated site risk and uncertainty assessment for impacts on surface and groundwater

    DEFF Research Database (Denmark)

    Thomsen, Nanna Isbak

    sites. In a conventional risk assessment of a contaminated site, risk is evaluated by assessing whether a concentration guideline is exceeded at a specific point of compliance in the water resource of interest. If the guideline is exceeded, it is concluded that the site poses a risk. However...... and samples collected in traditional groundwater boreholes. The detailed investigation revealed considerable variation in source composition, source strength and redox parameters. The variation was caused by the complex clay till geology and the heterogeneous nature of the landfill source. The impact on Risby......). This demonstrates that the method is flexible and that the beliefs can be assessed based on different types and levels of detail in the data. This work has addressed some important challenges in contaminated sites risk assessment and made great advances. These advances are now being applied by regulatory...

  18. Sensory Attenuation Assessed by Sensory Evoked Potentials in Functional Movement Disorders

    OpenAIRE

    Macerollo, A.; Chen, J. C.; Pareés, I.; Kassavetis, P; Kilner, J. M.; Edwards, M.J.

    2015-01-01

    Background Functional (psychogenic) movement disorders (FMD) have features associated with voluntary movement (e.g. distractibility) but patients report movements to be out of their control. One explanation for this phenomenon is that sense of agency for movement is impaired. The phenomenon of reduction in the intensity of sensory experience when movement is self-generated and a reduction in sensory evoked potentials (SEPs) amplitude at the onset of self-paced movement (sensory attenuation) h...

  19. Can Bayesian Belief Networks help tackling conceptual model uncertainties in contaminated site risk assessment?

    DEFF Research Database (Denmark)

    Troldborg, Mads; Thomsen, Nanna Isbak; McKnight, Ursula S.; Binning, Philip John; Bjerg, Poul Løgstrup

    models that are effective for integrating quantitative and qualitative information, and thus can strengthen decisions when empirical data are lacking. The developed BBN combines data from desk studies and initial site investigations with expert opinion to assess which of the conceptual models are more...... help inform future investigations at a contaminated site....

  20. Accumulation of Heavy Metals in Vegetable Species Planted in Contaminated Soils and the Health Risk Assessment

    OpenAIRE

    Hang Zhou; Wen-Tao Yang; Xin Zhou; Li Liu; Jiao-Feng Gu; Wen-Lei Wang; Jia-Ling Zou; Tao Tian; Pei-Qin Peng; Bo-Han Liao

    2016-01-01

    The objectives of the present study were to investigate heavy metal accumulation in 22 vegetable species and to assess the human health risks of vegetable consumption. Six vegetable types were cultivated on farmland contaminated with heavy metals (Pb, Cd, Cu, Zn, and As). The target hazard quotient (THQ) method was used to assess the human health risks posed by heavy metals through vegetable consumption. Clear differences were found in the concentrations of heavy metals in edible parts of the...

  1. Assessment of Regional Human Health Risks from Lead Contamination in Yunnan Province, Southwestern China

    OpenAIRE

    Lu, Lu; Cheng, Hongguang; Liu, XueLian; Xie, Jing; Li, Qian; Zhou, Tan

    2015-01-01

    Identification and management the 'critical risk areas' where hotspot lead exposures are a potential risk to human health, become a major focus of public health efforts in China. But the knowledge of health risk assessment of lead pollution at regional and national scales is still limited in China. In this paper, under the guidance of 'sources-pathways-receptors' framework, regional human health risk assessment model for lead contamination was developed to calculate the population health risk...

  2. Assessment of Soil Contamination in Patancheru Industrial Area, Hyderabad, Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    B. Dasaram

    2011-04-01

    Full Text Available Toxic trace metals concentrations in soil exert a decisive impact on soil quality and its use in food production particularly in an industrial area. An attempt is made here to study toxic metals such as Cr, Cu, Ni, Pb, Zn, including Ba, Co and V in representative soil samples from Patancheru industrial area near Hyderabad, Andhra Pradesh. It is a known polluted area and is one of the most contaminated regions where about 260 small and large-scale manufacturers of pharmaceuticals, paints, pesticides, chemicals, steel and metallic products have been functioning for over several decades. Toxic trace metal geochemical studies were carried out in fifteen representative soil samples collected from residential and agricultural area, to understand the spatial distribution and to assess the level of contamination on the basis of index of geoaccummulation, enrichment factor, contamination factor and degree of contamination. The various indices show that residential soils are contaminated with Cr, Ni and Pb (Cu to some extent. The agricultural area, although were invariably enriched in these toxic metals, showed comparatively less contamination possibly due to uptake by plants.

  3. Use of aqueous and solvent extraction to assess risk and bioavailability of contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Bordelon, N.; Huebner, H.; Washburn, K.; Donnelly, K.C.

    1995-12-31

    Contaminated media at Superfund sites typically consist of complex mixtures of organic and inorganic chemicals. These mixtures are difficult to characterize, both analytically and toxicologically, especially the complex mixtures of polycyclic aromatic hydrocarbons. The current approach to risk assessment assumes that all contaminants in the soil are available for human exposure. EPA protocol uses solvent extraction to remove chemicals from the soil as a basis for estimating risk to the human population. However, contaminants that can be recovered with a solvent extract may not represent chemicals that are available for exposure. A system using aqueous extraction provides a more realistic picture of what chemicals are bioavailable through leaching and ingestion. A study was conducted with coal tar contaminated soil spiked with benzo(a)pyrene, and trinitrotoluene. Samples were extracted with hexane:acetone and water titrated to pH 2 and pH 7. HPLC analysis demonstrated up to 35% and 29% recovery of contaminants from aqueous extracts with an estimated cancer risk one order of magnitude less than that for solvent extracts. Analysis using the Salmonella/microsome assay showed that solvent extracts were genotoxic with metabolic activation while aqueous extracts showed no genotoxicity. These results suggest that aqueous extraction may be useful in determining what contaminants are available for human exposure, as well as what compounds may pose a risk to human health.

  4. Use of aqueous and solvent extraction to assess risk and bioavailability of contaminated soil

    International Nuclear Information System (INIS)

    Contaminated media at Superfund sites typically consist of complex mixtures of organic and inorganic chemicals. These mixtures are difficult to characterize, both analytically and toxicologically, especially the complex mixtures of polycyclic aromatic hydrocarbons. The current approach to risk assessment assumes that all contaminants in the soil are available for human exposure. EPA protocol uses solvent extraction to remove chemicals from the soil as a basis for estimating risk to the human population. However, contaminants that can be recovered with a solvent extract may not represent chemicals that are available for exposure. A system using aqueous extraction provides a more realistic picture of what chemicals are bioavailable through leaching and ingestion. A study was conducted with coal tar contaminated soil spiked with benzo(a)pyrene, and trinitrotoluene. Samples were extracted with hexane:acetone and water titrated to pH 2 and pH 7. HPLC analysis demonstrated up to 35% and 29% recovery of contaminants from aqueous extracts with an estimated cancer risk one order of magnitude less than that for solvent extracts. Analysis using the Salmonella/microsome assay showed that solvent extracts were genotoxic with metabolic activation while aqueous extracts showed no genotoxicity. These results suggest that aqueous extraction may be useful in determining what contaminants are available for human exposure, as well as what compounds may pose a risk to human health

  5. Assessment of chemical and radioactive contaminants in coastal zones of Morocco

    International Nuclear Information System (INIS)

    Full text: The aim of this study is the assessment of levels of chemical and radioactive contaminants along the Moroccan coast from Ttouan to Dakhla. For the chemical contaminants, the study was focused on the determination of heavy metal concentrations (Pb, Cd, Hg), organochlorine pesticides and polychlorobipheny (PCB) in bivalve molluscs and sediment cores. Concerning the radioactive contaminants, a special attention was devoted to natural radionuclides especially 210Po and 210Pb concentrations in mollusc samples and anthropogenic radionuclides, particularly 137Cs in mollusc and sediment samples. The preliminary results didn't indicate any alarming contamination. Heavy metal concentrations didn't exceed 2.98, 0.87 and 0.01 mg/kg for Pb, Cd and Hg respectively. 210Po activities varied from 275 to 7780 Bq/kg. Therefore, the concentration values are generally lower than the admissible norms for the consumption of bivalve molluscs. However, significant variations of 210Po and 210Pb concentrations as well as heavy metals in mollusc samples were observed among the investigated stations reflecting the impact of industrial activities along the littoral. On the other hand, the study of the trend of contaminants during the last three years showed a reduction of the contaminant concentrations in 2011 compared to 2010. This project conducted by CNESTEN and INRH is undertaken within the Regional Project RAF7009 of IAEA on Integrated Approach for Marine Pollution Monitoring Using Nuclear Analytical Techniques

  6. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site at Grand Junction, Colorado. Revision 1

    International Nuclear Information System (INIS)

    This risk assessment evaluates potential impacts to public health or the environment resulting from ground water contamination at the former uranium mill processing site. The tailings and other contaminated material at this site were placed in an off-site disposal cell by the US Department of Energy's (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. The remedial activities at the site were conducted from 1989 to 1993. Currently, the UMTRA Project is evaluating ground water contamination. This risk assessment evaluates the most contaminated ground water that flows beneath the processing site toward the Colorado River. The monitor wells that have consistently shown the highest concentrations of most contaminants are used to assess risk. This risk assessment will be used in conjunction with additional activities and documents to determine what remedial action may be needed for contaminated ground water at the site

  7. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site at Grand Junction, Colorado. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    This risk assessment evaluates potential impacts to public health or the environment resulting from ground water contamination at the former uranium mill processing site. The tailings and other contaminated material at this site were placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. The remedial activities at the site were conducted from 1989 to 1993. Currently, the UMTRA Project is evaluating ground water contamination. This risk assessment evaluates the most contaminated ground water that flows beneath the processing site toward the Colorado River. The monitor wells that have consistently shown the highest concentrations of most contaminants are used to assess risk. This risk assessment will be used in conjunction with additional activities and documents to determine what remedial action may be needed for contaminated ground water at the site.

  8. PARATI: A program for radiological assessment after radioactive contamination of urban areas

    International Nuclear Information System (INIS)

    A dynamic model aimed on the assessment of the long-term consequences of an accidental contamination of urban environments has been developed. The model was designed to assess the radiation exposure, as a function of time, of the different kinds of people that uses the contaminated environment, the relative contribution of each exposure pathway to simulate the application of countermeasures and its effects on the reduction of surfaces contamination and on the exposure of the individuals and of the population. The model is an empirical one, mainly based on environmental data gathered after the Chernobyl and Goiania accidents, and takes into account climatic and population habits characteristics of tropical areas. The model was applied here to a contamination with the radionuclide 137Cs but can be easily adapted to other nuclides by changes on parameter values. An analysis of the variabilities associated to the model outputs regarding population habits, different kinds of urban environment and parameters uncertainty has shown that the main source of uncertainty on model predictions is associated to a correct knowledge of population characteristics, its habits and uses of the contaminated environment. (author)

  9. An assessment of soybeans and other vegetable proteins as source of salmonella contamination in pig production

    Directory of Open Access Journals (Sweden)

    Häggblom Per

    2010-02-01

    Full Text Available Abstract Background The impact of salmonella contaminated feed ingredients on the risk for spreading salmonella to pigs was assessed in response to two incidences when salmonella was spread by feed from two feed mills to 78 swine producing herds. Methods The assessment was based on results from the salmonella surveillance of feed ingredients before introduction to feed mills and from HACCP - based surveillance of the feed mills. Results from the mills of the Company (A that produced the salmonella contaminated feed, were by the Chi. Square test compared to the results from all the other (B - E feed producers registered in Sweden. Isolated serovars were compared to serovars from human cases of salmonellosis. Results Salmonella (28 serovars was frequently isolated from imported consignments of soybean meal (14.6% and rape seed meal (10.0%. Company A largely imported soybean meal from crushing plants with a history of unknown or frequent salmonella contamination. The risk for consignments of vegetable proteins to be salmonella contaminated was 2.4 times (P Conclusions Salmonella contaminated feed ingredients are an important source for introducing salmonella into the feed and food chain. Effective HACCP-based control and associated corrective actions are required to prevent salmonella contamination of feed. Efforts should be taken to prevent salmonella contamination already at the crushing plants. This is challenge for the EU - feed industry due to the fact that 98% of the use of soybean/meal, an essential feed ingredient, is imported from crushing plants of third countries usually with an unknown salmonella status.

  10. Use of life cycle assessments to evaluate the environmental footprint of contaminated sediment remediation.

    Science.gov (United States)

    Sparrevik, Magnus; Saloranta, Tuomo; Cornelissen, Gerard; Eek, Espen; Fet, Annik Magerholm; Breedveld, Gijs D; Linkov, Igor

    2011-05-15

    Ecological and human risks often drive the selection of remedial alternatives for contaminated sediments. Traditional human and ecological risk assessment (HERA) includes assessing risk for benthic organisms and aquatic fauna associated with exposure to contaminated sediments before and after remediation as well as risk for human exposure but does not consider the environmental footprint associated with implementing remedial alternatives. Assessment of environmental effects over the whole life cycle (i.e., Life Cycle Assessment, LCA) could complement HERA and help in selecting the most appropriate sediment management alternative. Even though LCA has been developed and applied in multiple environmental management cases, applications to contaminated sediments and marine ecosystems are in general less frequent. This paper implements LCA methodology for the case of the polychlorinated dibenzo-p-dioxins and -furans (PCDD/F)-contaminated Grenland fjord in Norway. LCA was applied to investigate the environmental footprint of different active and passive thin-layer capping alternatives as compared to natural recovery. The results showed that capping was preferable to natural recovery when analysis is limited to effects related to the site contamination. Incorporation of impacts related to the use of resources and energy during the implementation of a thin layer cap increase the environmental footprint by over 1 order of magnitude, making capping inferior to the natural recovery alternative. Use of biomass-derived activated carbon, where carbon dioxide is sequestered during the production process, reduces the overall environmental impact to that of natural recovery. The results from this study show that LCA may be a valuable tool for assessing the environmental footprint of sediment remediation projects and for sustainable sediment management. PMID:21520943

  11. Logistic regression modeling to assess groundwater vulnerability to contamination in Hawaii, USA

    Science.gov (United States)

    Mair, Alan; El-Kadi, Aly I.

    2013-10-01

    Capture zone analysis combined with a subjective susceptibility index is currently used in Hawaii to assess vulnerability to contamination of drinking water sources derived from groundwater. In this study, we developed an alternative objective approach that combines well capture zones with multiple-variable logistic regression (LR) modeling and applied it to the highly-utilized Pearl Harbor and Honolulu aquifers on the island of Oahu, Hawaii. Input for the LR models utilized explanatory variables based on hydrogeology, land use, and well geometry/location. A suite of 11 target contaminants detected in the region, including elevated nitrate (> 1 mg/L), four chlorinated solvents, four agricultural fumigants, and two pesticides, was used to develop the models. We then tested the ability of the new approach to accurately separate groups of wells with low and high vulnerability, and the suitability of nitrate as an indicator of other types of contamination. Our results produced contaminant-specific LR models that accurately identified groups of wells with the lowest/highest reported detections and the lowest/highest nitrate concentrations. Current and former agricultural land uses were identified as significant explanatory variables for eight of the 11 target contaminants, while elevated nitrate was a significant variable for five contaminants. The utility of the combined approach is contingent on the availability of hydrologic and chemical monitoring data for calibrating groundwater and LR models. Application of the approach using a reference site with sufficient data could help identify key variables in areas with similar hydrogeology and land use but limited data. In addition, elevated nitrate may also be a suitable indicator of groundwater contamination in areas with limited data. The objective LR modeling approach developed in this study is flexible enough to address a wide range of contaminants and represents a suitable addition to the current subjective approach.

  12. The development of assessment and remediation guidelines for contaminated soils, a review of the science

    International Nuclear Information System (INIS)

    Soil contamination is no longer restricted to isolated incidents and locations; it is a general and contentious problem. However, the problem is complex, starting with the very definition of what level and type of contamination is unacceptable. A myriad of regulatory and de facto guidelines have emerged, and they are extremely fragmented, inconsistent and incomplete. This review attempts to summarize the historical development of assessment and remediation guidelines, to highlight the unique difficulties of the problem, and then to discuss the scientific information that exists and that is needed to improve guidelines. This is an unlimited scope for research on this subject. (author)

  13. Assessing TNT and DNT groundwater contamination by compound-specific isotope analysis and 3H-3He groundwater dating: a case study in Portugal.

    Science.gov (United States)

    Amaral, Helena I F; Fernandes, Judite; Berg, Michael; Schwarzenbach, René P; Kipfer, Rolf

    2009-10-01

    Trinitrotoluene (TNT) and dinitrotoluene (DNT) originating from 50 years of explosives production have heavily contaminated two stacked aquifers in the vicinity of Lisboa, Portugal. To assess if these poly-nitroaromatic compounds (P-NACs) are being degraded in the subsurface, tracer-based groundwater dating techniques combined with compound-specific isotope analyses (CSIA) were applied. The groundwater residence times were distinctly different in the two aerobic aquifers, as determined by the tritium ((3)H)-(3)He method. In the contaminated zones, the upper aquifer exhibited groundwater ages of 25 years, whereas the lower (presumably confined) aquifer contained hardly any tritium which indicates water ages >55 years. P-NACs-containing waste waters are known to have leaked into the upper, unconfined aquifer. However, P-NACs were present in both aquifers in high concentrations (up to 33000 microg L(-1) TNT), which implies a hydraulic connection, although tritium concentrations and chemical data suggest two separated aquifers. Based on the (3)H-(3)He groundwater dating and the presence of very high P-NAC concentrations, the contamination of the lower aquifer must have happened during the early stage of the explosive production, i.e. >50 years ago. Despite this 'old' contamination, TNT and DNT have not been transformed until to date as is demonstrated by the negligible changes in their carbon isotopic signatures (delta(13)C). Thus, P-NACs are very recalcitrant to degradation at the investigated site. If the aquifers remain aerobic, TNT and DNT are expected to persist in the subsurface for many decades to centuries. The presented approach of assessing time scales of natural attenuation at the field scale by the combination of CSIA and (3)H-(3)He water dating has the potential to be applied to any other groundwater contaminants, such as chlorinated hydrocarbons, gasoline components, heterocyclic carbenes, or polyaromatic hydrocarbons. PMID:19740509

  14. Sensory Attenuation Assessed by Sensory Evoked Potentials in Functional Movement Disorders.

    Directory of Open Access Journals (Sweden)

    Antonella Macerollo

    Full Text Available Functional (psychogenic movement disorders (FMD have features associated with voluntary movement (e.g. distractibility but patients report movements to be out of their control. One explanation for this phenomenon is that sense of agency for movement is impaired. The phenomenon of reduction in the intensity of sensory experience when movement is self-generated and a reduction in sensory evoked potentials (SEPs amplitude at the onset of self-paced movement (sensory attenuation have been linked to sense of agency for movement.We compared amplitude of SEPs from median nerve stimulation at rest and at the onset of a self-paced movement of the thumb in 17 patients with FMD and 17 healthy controls.Patients showed lack of attenuation of SEPs at the onset of movement compared to reduction in amplitude of SEPs in controls. FMD patients had significantly different ratios of movement onset to rest SEPs than did healthy controls at each electrode: 0.79 in healthy controls and 1.35 in patients at F3 (t = -4.22, p<0.001, 0.78 in healthy controls and 1.12 at patients C3 (t = -3.15, p = 0.004 and 0.77 in healthy controls and 1.05 at patients P3 (t = -2.88, p = 0.007.Patients with FMD have reduced sensory attenuation as measured by SEPs at onset of self-paced movement. This finding can be plausibly linked to impairment of sense of agency for movement in these patients.

  15. Stochastic simulation experiment to assess radar rainfall retrieval uncertainties associated with attenuation and its correction

    Directory of Open Access Journals (Sweden)

    R. Uijlenhoet

    2008-03-01

    Full Text Available As rainfall constitutes the main source of water for the terrestrial hydrological processes, accurate and reliable measurement and prediction of its spatial and temporal distribution over a wide range of scales is an important goal for hydrology. We investigate the potential of ground-based weather radar to provide such measurements through a theoretical analysis of some of the associated observation uncertainties. A stochastic model of range profiles of raindrop size distributions is employed in a Monte Carlo simulation experiment to investigate the rainfall retrieval uncertainties associated with weather radars operating at X-, C-, and S-band. We focus in particular on the errors and uncertainties associated with rain-induced signal attenuation and its correction for incoherent, non-polarimetric, single-frequency, operational weather radars. The performance of two attenuation correction schemes, the (forward Hitschfeld-Bordan algorithm and the (backward Marzoug-Amayenc algorithm, is analyzed for both moderate (assuming a 50 km path length and intense Mediterranean rainfall (for a 30 km path. A comparison shows that the backward correction algorithm is more stable and accurate than the forward algorithm (with a bias in the order of a few percent for the former, compared to tens of percent for the latter, provided reliable estimates of the total path-integrated attenuation are available. Moreover, the bias and root mean square error associated with each algorithm are quantified as a function of path-averaged rain rate and distance from the radar in order to provide a plausible order of magnitude for the uncertainty in radar-retrieved rain rates for hydrological applications.

  16. Rapid Analysis of Eukaryotic Bioluminescence to Assess Potential Groundwater Contamination Events

    Directory of Open Access Journals (Sweden)

    Zacariah L. Hildenbrand

    2015-01-01

    Full Text Available Here we present data using a bioluminescent dinoflagellate, Pyrocystis lunula, in a toxicological bioassay to rapidly assess potential instances of groundwater contamination associated with natural gas extraction. P. lunula bioluminescence can be quantified using spectrophotometry as a measurement of organismal viability, with normal bioluminescent output declining with increasing concentration(s of aqueous toxicants. Glutaraldehyde and hydrochloric acid (HCl, components used in hydraulic fracturing and shale acidization, triggered significant toxicological responses in as little as 4 h. Conversely, P. lunula was not affected by the presence of arsenic, selenium, barium, and strontium, naturally occurring heavy metal ions potentially associated with unconventional drilling activities. If exogenous compounds, such as glutaraldehyde and HCl, are thought to have been introduced into groundwater, quantification of P. lunula bioluminescence after exposure to water samples can serve as a cost-effective detection and risk assessment tool to rapidly assess the impact of putative contamination events attributed to unconventional drilling activity.

  17. A risk assessment tool for contaminated sites in low-permeability fractured media

    DEFF Research Database (Denmark)

    Chambon, Julie Claire Claudia; Binning, Philip John; Jørgensen, P.R.; Bjerg, Poul Løgstrup

    2010-01-01

    A risk assessment tool for contaminated sites in low-permeability fractured media is developed, based on simple transient and steady-state analytical solutions. The tool, which explicitly takes into account the transport along fractures, covers different source geometries and can be applied to a...... wide range of compounds (conservative, sorbing, degradable). The superiority of this risk assessment tool compared to an Equivalent Porous Media (EPM) model is clearly demonstrated on experimental data. The use of the model for risk assessment is illustrated for diffuse pesticide sources in a Danish...... catchment. The model simulates well the presence of pesticides in drinking water wells and predicts the contamination duration, however, the early breakthrough and long term tailing cannot be validated due to lack of long term monitoring data....

  18. Metal uptake by homegrown vegetables - the relative importance in human health risk assessments at contaminated sites.

    Science.gov (United States)

    Augustsson, Anna L M; Uddh-Söderberg, Terese E; Hogmalm, K Johan; Filipsson, Monika E M

    2015-04-01

    Risk assessments of contaminated land often involve the use of generic bioconcentration factors (BCFs), which express contaminant concentrations in edible plant parts as a function of the concentration in soil, in order to assess the risks associated with consumption of homegrown vegetables. This study aimed to quantify variability in BCFs and evaluate the implications of this variability for human exposure assessments, focusing on cadmium (Cd) and lead (Pb) in lettuce and potatoes sampled around 22 contaminated glassworks sites. In addition, risks associated with measured Cd and Pb concentrations in soil and vegetable samples were characterized and a probabilistic exposure assessment was conducted to estimate the likelihood of local residents exceeding tolerable daily intakes. The results show that concentrations in vegetables were only moderately elevated despite high concentrations in soil, and most samples complied with applicable foodstuff legislation. Still, the daily intake of Cd (but not Pb) was assessed to exceed toxicological thresholds for about a fifth of the study population. Bioconcentration factors were found to vary more than indicated by previous studies, but decreasing BCFs with increasing metal concentrations in the soil can explain why the calculated exposure is only moderately affected by the choice of BCF value when generic soil guideline values are exceeded and the risk may be unacceptable. PMID:25723126

  19. Risk assessment of urban soils contamination: The particular case of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Cachada, A; da Silva, E Ferreira; Duarte, A C; Pereira, R

    2016-05-01

    The assessment of soil quality and characterization of potential risks to the environment and human health can be a very difficult task due to the heterogeneity and complexity of the matrix, the poor understanding about the fate of contaminants in the soil matrix, scarcity of toxicological/ecotoxicological data and variability of guidelines. In urban soils these difficulties are enhanced by the patchy nature of urban areas and the presence of complex mixtures of organic and inorganic contaminants resulting from diffuse pollution caused by urban activities (e.g. traffic, industrial activity, and burning of carbon sources for heating). Yet, several tools are available which may help to assess the risks of soil contamination in a simpler, cost effective and reliable way. Within these tools, a tiered risk assessment (RA) approach, first based on a chemical screening in combination with geostatistical tools, may be very useful in urban areas. However, there is still much to improve and a long way to go in order to obtain a reliable RA, especially in the case of hydrophobic organic compounds such as polycyclic aromatic hydrocarbons (PAHs). This paper aims at proposing a RA framework to assess the environmental and human health risks of PAHs present in urban soils, based on existing models. In addition, a review on ecotoxicological, toxicological, and exposure assessment data was made, as well as of the existing soil quality guidelines for PAHs that can be used in the RA process. PMID:26878639

  20. The Thule accident: Assessment of radiation doses from terrestrial radioactive contamination

    Energy Technology Data Exchange (ETDEWEB)

    Ulbak, K. (National Institute of Radiation Protection, Herlev (Denmark))

    2011-12-15

    Risoe DTU has carried out research on the terrestrial contamination in the Thule area after the radioactive contents of four nuclear weapons were dispersed following the crash of an American B-52 bomber in 1968. The results of Risoe DTU's studies are described in the report Thule-2007 - Investigation of radioactive pollution on land, which covers all measurements that were carried out on land in Thule in the years 2003, 2006, 2007 and 2008. The present report uses Risoe DTU's report as a basis for assessing radiation doses and consequently the risk for individuals as a result of terrestrial radioactive contamination in the Thule area. The assessment of radiation doses involves a number of conservative assumptions, estimates, and measurements, all of which are subject to considerable uncertainty. In some cases, models have been used based on experiences from other contaminated areas elsewhere in the world, which are subject to climatic and other conditions that diverge from those in the Thule area. The calculated doses are thus associated with considerable uncertainty, which must be taken into account when the results are used for comparison and when the risks of staying in the Thule area are assessed. It has therefore been chosen to provide the assessed radiation doses in the form of indicative orders of magnitude, which are applicable to everyone who might stay in the area, across various age groups. If the estimated doses in this report are combined with the National Institute of Radiation Protection's recommended reference level for contamination as a result of the Thule Accident of 1 mSv/year, the assessed magnitudes of radiation doses for inhalation and ingestion as exposure pathways are many orders of magnitude below the reference level (10,000-10 million times smaller). The wound contamination exposure pathway has a magnitude of radiation dose that is smaller than the reference level by a factor of 10-1000, and it should be recalled that the

  1. Risk assessment of contaminated sites - an international status report; Saastuneiden maiden riskinarviointi - kansanvaelinen tilanne

    Energy Technology Data Exchange (ETDEWEB)

    Mroueh, U.-M. [VTT Chemical Technology, Espoo (Finland)

    2000-07-01

    The aim of the study was to collect the existing experiences with the use of risk assessment in the remedial decision making of contaminated sites in some European countries and North America, and to weigh up the exploitability of these experiences in Finland. The study is focused on health and environmental risk assessment in the following countries: the United States, Canada, the Netherlands, Germany, and the United Kingdom. Also the situation in Nordic countries is discussed. Most of the experience with risk assessment based remedial decision making comes from the USA and from some Canadian provinces. In the Netherlands the development of health and ecological risk assessment methodologies and procedures was started in the beginning of nineties. The principal application has, however, been in the determination of the urgency of the clean up. Also in other countries concerned in this study the opportunity of using site-specific risk assessment is included into the recent contaminated soil regulations. The experience about practical applications is still very limited. Site specific risk assessment was first introduced in the USA in the eighties. The health risk assessment models and procedures developed in other countries are still mainly based on U.S. health risk assessment models. In the USA, the basic principle was to make all the remedial decisions on the basis of site specific health and environmental risk assessment. EPA, the Environmental Protection Agency, did not deem the use of soil target values necessary or even acceptable. Some states developed; however, own guide values. It was assumed that there are only some hundreds of severely contaminated hazardous waste sites to be remedied. When the extent of the contaminated site problem and the need to remediate sites containing various levels of contamination became evident, tiered systems for regulation of contaminated sites have been more and more accepted. Earlier in most European countries, and partly

  2. Contaminant fluxes through site containment barriers: Performance assessment and illustrative results

    International Nuclear Information System (INIS)

    Contaminant mass flux by advective and diffusive transport is predicted for five containment barriers that use one or more clay liners, flexible membrane liners (FMLs), or liquid collection and removal systems (LCRS)s. Barriers are engineered systems intended to contain and isolate site contaminants from the environment. Barriers include liners, caps, and cutoff walls. Barriers may be used in contaminated-site cleanups (including CERCLA and RCRA), RCRA landfills, or other RCRA TSDFs. Concepts are provided for barrier performance assessment, including analysis and optimization, for meeting performance requirements and controlling risk at minimum cost. Concepts and results can help in planning, designing, or evaluating and communicating, the use or effectiveness of proposed or existing barriers for site cleanups or waste containment. 15 refs., 6 figs., 5 tabs

  3. Development and application of bioassays for a site-specific risk assessment of contaminated soil

    OpenAIRE

    Rila, J.-P.

    2008-01-01

    Soil risk assessment based on generic approaches is accompanied by a large number of uncertainties. In site-specific risk assessment aimed at identifying the actual effects on the ecosystem by using e.g. bioassays in soil elutriates and taking into account land-use these uncertainties can be largely reduced. In this thesis the application and development of bioassays for a site-specific risk assessment of contaminated soil has been discussed. The first part of this thesis deals with the influ...

  4. Assessment Of Coronary Artery Aneurysms Using Transluminal Attenuation Gradient And Computational Modeling In Kawasaki Disease Patients

    Science.gov (United States)

    Grande Gutierrez, Noelia; Kahn, Andrew; Shirinsky, Olga; Gagarina, Nina; Lyskina, Galina; Fukazawa, Ryuji; Owaga, Shunichi; Burns, Jane; Marsden, Alison

    2015-11-01

    Kawasaki Disease (KD) can result in coronary artery aneurysms (CAA) in up to 25% of patients, putting them at risk of thrombus formation, myocardial infarction and sudden death. Clinical guidelines recommend CAA diameter >8 mm as the arbitrary criterion for initiating systemic anticoagulation. KD patient specific modeling and flow simulations suggest that hemodynamic data can predict regions at increased risk of thrombosis. Transluminal Attenuation Gradient (TAG) is determined from the change in radiological attenuation per vessel length and has been proposed as a non-invasive method for characterizing coronary stenosis from CT Angiography. We hypothesized that CAA abnormal flow could be quantified using TAG. We computed hemodynamics for patient specific coronary models using a stabilized finite element method, coupled numerically to a lumped parameter network to model the heart and vascular boundary conditions. TAG was quantified in the major coronary arteries. We compared TAG for aneurysmal and normal arteries and we analyzed TAG correlation with hemodynamic and geometrical parameters. Our results suggest that TAG may provide hemodynamic data not available from anatomy alone. TAG represents a possible extension to standard CTA that could help to better evaluate the risk of thrombus formation in KD.

  5. Transluminal Attenuation Gradient for Thrombotic Risk Assessment in Kawasaki Disease Patients with Coronary Artery Aneurysms

    Science.gov (United States)

    Grande Gutierrez, Noelia; Kahn, Andrew; Burns, Jane; Marsden, Alison

    2014-11-01

    Kawasaki Disease (KD) can result in coronary aneurysms in up to 25% of patients if not treated early putting patients at risk of thrombus formation, myocardial infarction and sudden death. Clinical guidelines for administering anti-coagulation therapy currently rely on anatomy alone. Previous studies including patient specific modeling and computer simulations in KD patients have suggested that hemodynamic data can predict regions susceptible to thrombus formation. In particular, high Particle Residence Time gradient (PRTg) regions have shown to correlate with regions of thrombus formation. Transluminal Attenuation Gradient (TAG) is determined from the change in radiological attenuation per vessel length. TAG has been used for characterizing coronary artery stenoses, however this approach has not yet been used in aneurysmal vessels. The aim of this study is to analyze the correlation between TAG and PRTg in KD patients with aneurysms and evaluate the use of TAG as an index to quantify thrombotic risk. Patient specific anatomic models for fluids simulations were constructed from CT angiographic image data from 3 KD aneurysm patients and one normal control. TAG values for the aneurysm patients were markedly lower than for the non-aneurysmal patient (mean -18.38 vs. -2). In addition, TAG values were compared to PRTg obtained for each patient. Thrombotic risk stratification for KD aneurysms may be improved by incorporating TAG and should be evaluated in future prospective studies.

  6. Using sequential indicator simulation to assess the uncertainty of delineating heavy-metal contaminated soils

    International Nuclear Information System (INIS)

    Mapping the spatial distribution of soil pollutants is essential for delineating contaminated areas. Currently, geostatistical interpolation, kriging, is increasingly used to estimate pollutant concentrations in soils. The kriging-based approach, indicator kriging (IK), may be used to model the uncertainty of mapping. However, a smoothing effect is usually produced when using kriging in pollutant mapping. The detailed spatial patterns of pollutants could, therefore, be lost. The local uncertainty of mapping pollutants derived by the IK technique is referred to as the conditional cumulative distribution function (ccdf) for one specific location (i.e. single-location uncertainty). The local uncertainty information obtained by IK is not sufficient as the uncertainty of mapping at several locations simultaneously (i.e. multi-location uncertainty or spatial uncertainty) is required to assess the reliability of the delineation of contaminated areas. The simulation approach, sequential indicator simulation (SIS), which has the ability to model not only single, but also multi-location uncertainties, was used, in this study, to assess the uncertainty of the delineation of heavy metal contaminated soils. To illustrate this, a data set of Cu concentrations in soil from Taiwan was used. The results show that contour maps of Cu concentrations generated by the SIS realizations exhausted all the spatial patterns of Cu concentrations without the smoothing effect found when using the kriging method. Based on the SIS realizations, the local uncertainty of Cu concentrations at a specific location of x', refers to the probability of the Cu concentration z(x') being higher than the defined threshold level of contamination (zc). This can be written as ProbSIS[z(x')>zc], representing the probability of contamination. The probability map of ProbSIS[z(x')>zc] can then be used for delineating contaminated areas. In addition, the multi-location uncertainty of an area A,delineated as

  7. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Naturita, Colorado

    International Nuclear Information System (INIS)

    The Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (phase I), and the Ground Water Project (phase II). For the UMTRA Project site located near Naturita, Colorado (the Naturita site), phase I involves the removal of radioactively contaminated soils and materials and their transportation to a disposal site at Union Carbide Corporation's Upper Burbank Repository at Uravan, Colorado, about 13 road miles (mi) (21 kilometers [km]) to the northwest. No uranium mill tailings are involved because the tailings were removed from the Naturita site and placed at Coke Oven, Colorado, during 1977 to 1979. Phase II of the project will evaluate the nature and extent of ground water contamination resulting from uranium processing and its effect on human health or the environment; and will determine site-specific ground water compliance strategies in accordance with the US Environmental Protection Agency (EPA) ground water standards established for the UMTRA Project. Human health risks could occur from drinking water pumped from a hypothetical well drilled in the contaminated ground water area. Environmental risks may result if plants or animals are exposed to contaminated ground water, or surface water that has received contaminated ground water. Therefore, a risk assessment is conducted for the Naturita site. This risk assessment report is the first site-specific document prepared for the Ground Water Project at the Naturita site. What follows is an evaluation of current and possible future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will be used to determine whether any action is needed to protect human health or the environment

  8. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Naturita, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    The Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (phase I), and the Ground Water Project (phase II). For the UMTRA Project site located near Naturita, Colorado (the Naturita site), phase I involves the removal of radioactively contaminated soils and materials and their transportation to a disposal site at Union Carbide Corporation`s Upper Burbank Repository at Uravan, Colorado, about 13 road miles (mi) (21 kilometers [km]) to the northwest. No uranium mill tailings are involved because the tailings were removed from the Naturita site and placed at Coke Oven, Colorado, during 1977 to 1979. Phase II of the project will evaluate the nature and extent of ground water contamination resulting from uranium processing and its effect on human health or the environment; and will determine site-specific ground water compliance strategies in accordance with the US Environmental Protection Agency (EPA) ground water standards established for the UMTRA Project. Human health risks could occur from drinking water pumped from a hypothetical well drilled in the contaminated ground water area. Environmental risks may result if plants or animals are exposed to contaminated ground water, or surface water that has received contaminated ground water. Therefore, a risk assessment is conducted for the Naturita site. This risk assessment report is the first site-specific document prepared for the Ground Water Project at the Naturita site. What follows is an evaluation of current and possible future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will be used to determine whether any action is needed to protect human health or the environment.

  9. Assessing the fate of biodegradable volatile organic contaminants in unsaturated soil filter systems

    Science.gov (United States)

    Thullner, Martin; de Biase, Cecilia; Hanzel, Joanna; Reger, Daniel; Wick, Lukas; Oswald, Sascha; van Afferden, Manfred; Schmidt, Axel; Reiche, Nils; Jechalke, Sven

    2010-05-01

    The assessment of contaminant biodegradation in the subsurface is challenged by various abiotic processes leading to a reduction of contaminant concentration without a destructive mass removal of the contaminant. In unsaturated porous media, this interplay of processes is further complicated by volatilization. Many organic contaminants are sufficiently volatile to allow for significant fluxes from the water phase into the soil air, which can eventually lead to an emission of contaminants into the atmosphere. Knowledge of the magnitude of these emissions is thus required to evaluate the efficiency of bioremediation in such porous media and to estimate potential risks due to these emissions. In the present study, vertical flow constructed wetlands were investigated at the pilot scale as part of the SAFIRA II project. The investigated wetland system is intermittently irrigated by contaminated groundwater containing the volatile compounds benzene and MTBE. Measured concentration at the in- and outflow of the system demonstrate a high mass removal rate, but the highly transient flow and transport processes in the system challenge the quantification of biodegradation and volatilization and their contribution to the observed mass removal. By a combination of conservative solute tracer tests, stable isotope fractionation and measurements of natural radon concentration is the treated groundwater is was possible to determine the contribution of biodegradation and volatilization to total mass removal. The results suggest that for the investigated volatile compounds biodegradation is the dominating mass removal process with volatilization contributing only to minor or negligible amounts. These results can be confirmed by reactive transport simulations and were further supported by laboratory studies showing that also gas phase gradients of volatile compounds can be affected by biodegradation suggesting the unsaturated zone to act as a biofilter for contaminants in the soil air.

  10. Groundwater Nitrate Contamination Risk Assessment: A Comparison of Parametric Systems and Simulation Modelling

    Directory of Open Access Journals (Sweden)

    Dario Sacco

    2007-01-01

    Full Text Available Groundwater nitrate contamination is a source of rising concern that has been faced through the introduction of several regulations in different countries. However the methodologies used in the definition of Nitrate Vulnerable Zones are not included in the regulations. The aim of this work was to compare different methodologies, used to asses groundwater nitrate contamination risks, based on parametric systems or simulation modelling. The work was carried out in Piedmont, Italy, in an area characterised by intensive animal husbandry, high N load, a shallow water table and a coarse type of sub-soil sediments. Only N loads from agricultural non-point sources were considered. Different methodologies with different level of information have been compared to determine the groundwater nitrate contamination risk assessment: N load, IPNOA index, the intrinsic contamination risk from nitrates, leached N and N concentration of the soil solution estimated by the simulation model. The good correlation between the IPNOA index and the intrinsic nitrate contamination risk revealed that the parameters that describe the soil in this area did not lead to a different classification of the parcels. The intrinsic nitrate contamination risk was greatly influenced by N fertilisation, however the effect of the soils increased the variability in comparison to the IPNOA index. The leached N and N concentration in the leaching were closely correlated. The dilution effect of percolated water was almost negligible. Both methodologies were slightly correlated to the N fertilisation and the two indexes. The correlations related to the intrinsic nitrate contamination risk was higher than those related to IPNOA, and this means that the effect of taking into account soil parameters increases the correlation to the prediction of the simulation model.

  11. Baseline risk assessment of ground water contamination at the inactive uriniferous lignite ashing site near Belfield, North Dakota

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-08-01

    This Baseline Risk Assessment of Ground Water Contamination at the Inactive Uraniferous Lignite Ashing Site Near Belfield, North Dakota, evaluates potential impacts to public health or the environment resulting from ground water contamination at the site where coal containing uranium was burned to produce uranium. The US Department of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Project is evaluating plans to remedy soil and ground water contamination at the site. Phase I of the UMTRA Project consists of determining the extent of soil contamination. Phase II of the UMTRA Project consists of evaluating ground water contamination. Under Phase II, results of this risk assessment will help determine what remedial actions may be necessary for contaminated ground water at the site. This risk assessment evaluates the potential risks to human health and the environment resulting from exposure to contaminated ground water as it relates to historic processing activities at the site. Potential risk is quantified for constituents introduced from the processing activities, and not for those constituents naturally occurring in water quality in the site vicinity. Background ground water quality has the potential to cause adverse health effects from exposure through drinking. Any risks associated with contaminants attributable to site activities are incremental to these risks from background ground water quality. This incremental risk from site-related contaminants is quantified in this risk assessment. The baseline risk from background water quality is incorporated only into the assessment of potential chemical interactions and the definition of the overall site condition.

  12. Baseline risk assessment of ground water contamination at the inactive uraniferous lignite ashing site near Belfield, North Dakota

    International Nuclear Information System (INIS)

    This Baseline Risk Assessment of Ground Water Contamination at the Inactive Uraniferous Lignite Ashing Site Near Belfield, North Dakota, evaluates potential impacts to public health or the environment resulting from ground water contamination at the site where coal containing uranium was burned to produce uranium. The US Department of Energy's Uranium Mill Tailings Remedial Action (UMTRA) Project is evaluating plans to remedy soil and ground water contamination at the site. Phase I of the UMTRA Project consists of determining the extent of soil contamination. Phase II of the UMTRA Project consists of evaluating ground water contamination. Under Phase II, results of this risk assessment will help determine what remedial actions may be necessary for contaminated ground water at the site. This risk assessment evaluates the potential risks to human health and the environment resulting from exposure to contaminated ground water as it relates to historic processing activities at the site. Potential risk is quantified for constituents introduced from the processing activities, and not for those constituents naturally occurring in water quality in the site vicinity. Background ground water quality has the potential to cause adverse health effects from exposure through drinking. Any risks associated with contaminants attributable to site activities are incremental to these risks from background ground water quality. This incremental risk from site-related contaminants is quantified in this risk assessment. The baseline risk from background water quality is incorporated only into the assessment of potential chemical interactions and the definition of the overall site condition

  13. A Contamination Vulnerability Assessment for the Santa Clara and San Mateo County Groundwater Basins

    International Nuclear Information System (INIS)

    In response to concerns expressed by the California Legislature and the citizenry of the State of California, the State Water Resources Control Board (SWRCB), implemented a program to assess groundwater quality, and provide a predictive capability for identifying areas that are vulnerable to contamination. The program was initiated in response to concern over public supply well closures due to contamination by chemicals such as MtBE from gasoline, and solvents from industrial operations. As a result of this increased awareness regarding groundwater quality, the Supplemental Report of the 1999 Budget Act mandated the SWRCB to develop a comprehensive ambient groundwater-monitoring plan, and led to the initiation of the Ambient Groundwater Monitoring and Assessment (GAMA) Program. The primary objective of the GAMA Program is to assess the water quality and to predict the relative susceptibility to contamination of groundwater resources throughout the state of California. Under the GAMA program, scientists from Lawrence Livermore National Laboratory (LLNL) collaborate with the SWRCB, the U.S. Geological Survey, the California Department of Health Services (DHS), and the California Department of Water Resources (DWR) to implement this groundwater assessment program. In 2001 and 2002, LLNL carried out this vulnerability study in the groundwater basins of Santa Clara County and San Mateo County, located to the south of the city of San Francisco. The goal of the study is to provide a probabilistic assessment of the relative vulnerability of groundwater used for the public water supply to contamination from surface sources. This assessment of relative contamination vulnerability is made based on the results of two types of analyses that are not routinely carried out at public water supply wells: ultra low-level measurement of volatile organic compounds (VOCs), and groundwater age dating (using the tritium-helium-3 method). In addition, stable oxygen isotope measurements

  14. A Contamination Vulnerability Assessment for the Santa Clara and San Mateo County Groundwater Basins

    Energy Technology Data Exchange (ETDEWEB)

    Moran, J E; Hudson, G B; Eaton, G F; Leif, R

    2004-01-06

    In response to concerns expressed by the California Legislature and the citizenry of the State of California, the State Water Resources Control Board (SWRCB), implemented a program to assess groundwater quality, and provide a predictive capability for identifying areas that are vulnerable to contamination. The program was initiated in response to concern over public supply well closures due to contamination by chemicals such as MtBE from gasoline, and solvents from industrial operations. As a result of this increased awareness regarding groundwater quality, the Supplemental Report of the 1999 Budget Act mandated the SWRCB to develop a comprehensive ambient groundwater-monitoring plan, and led to the initiation of the Ambient Groundwater Monitoring and Assessment (GAMA) Program. The primary objective of the GAMA Program is to assess the water quality and to predict the relative susceptibility to contamination of groundwater resources throughout the state of California. Under the GAMA program, scientists from Lawrence Livermore National Laboratory (LLNL) collaborate with the SWRCB, the U.S. Geological Survey, the California Department of Health Services (DHS), and the California Department of Water Resources (DWR) to implement this groundwater assessment program. In 2001 and 2002, LLNL carried out this vulnerability study in the groundwater basins of Santa Clara County and San Mateo County, located to the south of the city of San Francisco. The goal of the study is to provide a probabilistic assessment of the relative vulnerability of groundwater used for the public water supply to contamination from surface sources. This assessment of relative contamination vulnerability is made based on the results of two types of analyses that are not routinely carried out at public water supply wells: ultra low-level measurement of volatile organic compounds (VOCs), and groundwater age dating (using the tritium-helium-3 method). In addition, stable oxygen isotope measurements

  15. California GAMA Program: A Contamination Vulnerability Assessment for the Bakersfield Area

    Energy Technology Data Exchange (ETDEWEB)

    Moran, J E; Hudson, G B; Eaton, G F; Leif, R

    2004-11-01

    In response to concerns expressed by the California Legislature and the citizenry of the State of California, the State Water Resources Control Board (SWRCB), implemented a program to assess groundwater quality, and provide a predictive capability for identifying areas that are vulnerable to contamination. The program was initiated in response to concern over public supply well closures due to contamination by chemicals such as MTBE from gasoline, and solvents from industrial operations. As a result of this increased awareness regarding groundwater quality, the Supplemental Report of the 1999 Budget Act mandated the SWRCB to develop a comprehensive ambient groundwater-monitoring plan, and led to the initiation of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The primary objective of the GAMA Program is to assess the water quality and to predict the relative susceptibility to contamination of groundwater resources throughout the state of California. Under the GAMA program, scientists from Lawrence Livermore National Laboratory (LLNL) collaborate with the SWRCB, the U.S. Geological Survey (USGS), the California Department of Health Services (DHS), and the California Department of Water Resources (DWR) to implement this groundwater assessment program. In 2003, LLNL carried out this vulnerability study in the groundwater basin that underlies Bakersfield, in the southern San Joaquin Valley. The goal of the study is to provide a probabilistic assessment of the relative vulnerability of groundwater used for the public water supply to contamination from surface sources. This assessment of relative contamination vulnerability is made based on the results of two types of analyses that are not routinely carried out at public water supply wells: ultra low-level measurement of volatile organic compounds (VOCs), and groundwater age dating (using the tritium-helium-3 method). In addition, stable oxygen isotope measurements help determine the recharge water

  16. California GAMA Program: A Contamination Vulnerability Assessment for the Bakersfield Area

    International Nuclear Information System (INIS)

    In response to concerns expressed by the California Legislature and the citizenry of the State of California, the State Water Resources Control Board (SWRCB), implemented a program to assess groundwater quality, and provide a predictive capability for identifying areas that are vulnerable to contamination. The program was initiated in response to concern over public supply well closures due to contamination by chemicals such as MTBE from gasoline, and solvents from industrial operations. As a result of this increased awareness regarding groundwater quality, the Supplemental Report of the 1999 Budget Act mandated the SWRCB to develop a comprehensive ambient groundwater-monitoring plan, and led to the initiation of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The primary objective of the GAMA Program is to assess the water quality and to predict the relative susceptibility to contamination of groundwater resources throughout the state of California. Under the GAMA program, scientists from Lawrence Livermore National Laboratory (LLNL) collaborate with the SWRCB, the U.S. Geological Survey (USGS), the California Department of Health Services (DHS), and the California Department of Water Resources (DWR) to implement this groundwater assessment program. In 2003, LLNL carried out this vulnerability study in the groundwater basin that underlies Bakersfield, in the southern San Joaquin Valley. The goal of the study is to provide a probabilistic assessment of the relative vulnerability of groundwater used for the public water supply to contamination from surface sources. This assessment of relative contamination vulnerability is made based on the results of two types of analyses that are not routinely carried out at public water supply wells: ultra low-level measurement of volatile organic compounds (VOCs), and groundwater age dating (using the tritium-helium-3 method). In addition, stable oxygen isotope measurements help determine the recharge water

  17. Assessment of potential indigenous plant species for the phytoremediation of arsenic-contaminated areas of Bangladesh.

    Science.gov (United States)

    Mahmud, Rezwanul; Inoue, Naoto; Kasajima, Shin-Ya; Shaheen, Riffat

    2008-01-01

    Soil and water contaminated with arsenic (As) pose a major environmental and human health problem in Bangladesh. Phytoremediation, a plant-based technology, may provide an economically viable solution for remediating the As-polluted sites. The use of indigenous plants with a high tolerance and accumulation capacity for As may be a very convenient approach for phytoremediation. To assess the potential of native plant species for phytoremediation, plant and soil samples were collected from four As-contaminated (groundwater) districts in Bangladesh. The main criteria used for selecting plants for phytoremediation were high bioconcentration factors (BCFs) and translocation factors (TFs) of As. From the results of a screening of 49 plant species belonging to 29 families, only one species of fern (Dryopteris filix-mas), three herbs (Blumea lacera, Mikania cordata, and Ageratum conyzoides), and two shrubs (Clerodendrum trichotomum and Ricinus communis) were found to be suitable for phytoremediation. Arsenic bioconcentration and translocation factors > 1 suggest that these plants are As-tolerant accumulators with potential use in phytoextraction. Three floating plants (Eichhornia crassipes, Spirodela polyrhiza, and Azolla pinnata) and a common wetland weed (Monochoria vaginalis) also showed high BCF and TF values; therefore, these plants may be promising candidates for cleaningup As-contaminated surface water and wetland areas. The BCF of Oryza sativa, obtained from As-contaminated districts was > 1, which highlights possible food-chain transfer issues for As-contaminated areas in Bangladesh. PMID:18709925

  18. Biological assessment of contaminated land using earthworm biomarkers in support of chemical analysis

    International Nuclear Information System (INIS)

    Biological indicators can be used to assess polluted sites but their success depends on the availability of suitable assays. The aim of this study was to investigate the performance of two earthworm biomarkers, lysosomal membrane stability measured using the neutral red retention assay (NRR-T) and the total immune activity (TIA) assay, that have previously been established as responsive to chemical exposure. Responses of the two assays were measured following in situ exposure to complexly contaminated field soils at three industrial sites as well as urban and rural controls. The industrial sites were contaminated with a range of metal (cadmium, copper, lead, zinc, nickel and cobalt) and organic (including polycyclic aromatic hydrocarbons) contaminants, but at concentrations below the 'New Dutch List' Intervention concentrations. Exposed earthworms accumulated both metals and organic compounds at the contaminated sites, indicating that there was significant exposure. No effect on earthworm survival was found at any of the sites. Biomarker measurements, however, indicated significant effects, with lower NRR-T and TIA found in the contaminated soils when compared to the two controls. The results demonstrate that a comparison of soil pollutant concentrations with guideline values would not have unequivocally identified chemical exposure and toxic effect for soil organisms living in these soils. However, the earthworm biomarkers successfully identified significant exposure and biological effects caused by the mixture of chemicals present

  19. Chemical contamination assessment of Gulf of Mexico oysters in response to hurricanes Katrina and Rita.

    Science.gov (United States)

    Johnson, W E; Kimbrough, K L; Lauenstein, G G; Christensen, J

    2009-03-01

    Hurricane Katrina made landfall on August 29, 2005 and caused widespread devastation along the central Gulf Coast states. Less than a month later Hurricane Rita followed a similar track slightly west of Katrina's. A coordinated multi-agency response followed to collect water, sediment and tissue samples for a variety of chemical, biological and toxicological indicators. The National Oceanic and Atmospheric Administration's National Status and Trends Program (NS&T) participated in this effort by measuring chemical contamination in sediment and oyster tissue as part of the Mussel Watch Program, a long-term monitoring program to assess spatial and temporal trends in a wide range of coastal pollutants. This paper describes results for contaminants measured in oyster tissue collected between September 29 and October 10, 2005 and discusses the results in the context of Mussel Watch and its 20-year record of chemical contamination in the region and the nation. In general, levels of metals in oyster tissue were higher then pre- hurricane levels while organic contaminants were at or near record lows. No contaminant reported here exceeded the FDA action level for food safety. PMID:19051046

  20. Assessing microbial activities in metal contaminated agricultural volcanic soils - An integrative approach.

    Science.gov (United States)

    Parelho, C; Rodrigues, A S; Barreto, M C; Ferreira, N G C; Garcia, P

    2016-07-01

    Volcanic soils are unique naturally fertile resources, extensively used for agricultural purposes and with particular physicochemical properties that may result in accumulation of toxic substances, such as trace metals. Trace metal contaminated soils have significant effects on soil microbial activities and hence on soil quality. The aim of this study is to determine the soil microbial responses to metal contamination in volcanic soils under different agricultural land use practices (conventional, traditional and organic), based on a three-tier approach: Tier 1 - assess soil microbial activities, Tier 2 - link the microbial activity to soil trace metal contamination and, Tier 3 - integrate the microbial activity in an effect-based soil index (Integrative Biological Response) to score soil health status in metal contaminated agricultural soils. Our results showed that microbial biomass C levels and soil enzymes activities were decreased in all agricultural soils. Dehydrogenase and β-glucosidase activities, soil basal respiration and microbial biomass C were the most sensitive responses to trace metal soil contamination. The Integrative Biological Response value indicated that soil health was ranked as: organic>traditional>conventional, highlighting the importance of integrative biomarker-based strategies for the development of the trace metal "footprint" in Andosols. PMID:27057992

  1. Liver Steatosis Assessed by Controlled Attenuation Parameter (CAP) Measured with the XL Probe of the FibroScan: A Pilot Study Assessing Diagnostic Accuracy.

    Science.gov (United States)

    Sasso, Magali; Audière, Stéphane; Kemgang, Astrid; Gaouar, Farid; Corpechot, Christophe; Chazouillères, Olivier; Fournier, Céline; Golsztejn, Olivier; Prince, Stéphane; Menu, Yves; Sandrin, Laurent; Miette, Véronique

    2016-01-01

    To assess liver steatosis, the controlled attenuation parameter (CAP; giving an estimate of ultrasound attenuation ∼3.5 MHz) is available with the M probe of the FibroScan. We report on the adaptation of the CAP for the FibroScan XL probe (center frequency 2.5 MHz) without modifying the range of values (100-400 dB/m). CAP validation was successfully performed on Field II simulations and on tissue-mimicking phantoms. In vivo performance was assessed in a cohort of 59 patients spanning the range of steatosis. In vivo reproducibility was good and similar with both probes. The area under receiver operative characteristic curve was equal to 0.83/0.84 and 0.92/0.91 for the M/XL probes to detect >2% and >16% liver fat, respectively, as assessed by magnetic resonance imaging. Patients can now be assessed simultaneously for steatosis and fibrosis using the FibroScan, regardless of their morphology. PMID:26386476

  2. A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach for contaminated sites management

    International Nuclear Information System (INIS)

    Highlights: • Using interval mathematics to describe spatial and temporal variability and parameter uncertainty. • Using fuzzy theory to quantify variability of environmental guideline values. • Using probabilistic approach to integrate interval concentrations and fuzzy environmental guideline. • Establishment of dynamic multimedia environmental integrated risk assessment framework. -- Abstract: A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach was developed for contaminated sites management. The contaminant concentrations were simulated by a validated interval dynamic multimedia fugacity model, and different guideline values for the same contaminant were represented as a fuzzy environmental guideline. Then, the probability of violating environmental guideline (Pv) can be determined by comparison between the modeled concentrations and the fuzzy environmental guideline, and the constructed relationship between the Pvs and environmental risk levels was used to assess the environmental risk level. The developed approach was applied to assess the integrated environmental risk at a case study site in China, simulated from 1985 to 2020. Four scenarios were analyzed, including “residential land” and “industrial land” environmental guidelines under “strict” and “loose” strictness. It was found that PAH concentrations will increase steadily over time, with soil found to be the dominant sink. Source emission in soil was the leading input and atmospheric sedimentation was the dominant transfer process. The integrated environmental risks primarily resulted from petroleum spills and coke ovens, while the soil environmental risks came from coal combustion. The developed approach offers an effective tool for quantifying variability and uncertainty in the dynamic multimedia integrated environmental risk assessment and the contaminated site management

  3. A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach for contaminated sites management

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yan; Wen, Jing-ya; Li, Xiao-li; Wang, Da-zhou; Li, Yu, E-mail: liyuxx8@hotmail.com

    2013-10-15

    Highlights: • Using interval mathematics to describe spatial and temporal variability and parameter uncertainty. • Using fuzzy theory to quantify variability of environmental guideline values. • Using probabilistic approach to integrate interval concentrations and fuzzy environmental guideline. • Establishment of dynamic multimedia environmental integrated risk assessment framework. -- Abstract: A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach was developed for contaminated sites management. The contaminant concentrations were simulated by a validated interval dynamic multimedia fugacity model, and different guideline values for the same contaminant were represented as a fuzzy environmental guideline. Then, the probability of violating environmental guideline (Pv) can be determined by comparison between the modeled concentrations and the fuzzy environmental guideline, and the constructed relationship between the Pvs and environmental risk levels was used to assess the environmental risk level. The developed approach was applied to assess the integrated environmental risk at a case study site in China, simulated from 1985 to 2020. Four scenarios were analyzed, including “residential land” and “industrial land” environmental guidelines under “strict” and “loose” strictness. It was found that PAH concentrations will increase steadily over time, with soil found to be the dominant sink. Source emission in soil was the leading input and atmospheric sedimentation was the dominant transfer process. The integrated environmental risks primarily resulted from petroleum spills and coke ovens, while the soil environmental risks came from coal combustion. The developed approach offers an effective tool for quantifying variability and uncertainty in the dynamic multimedia integrated environmental risk assessment and the contaminated site management.

  4. Risk assessment for furan contamination through the food chain in Belgian children.

    Science.gov (United States)

    Scholl, Georges; Huybrechts, Inge; Humblet, Marie-France; Scippo, Marie-Louise; De Pauw, Edwin; Eppe, Gauthier; Saegerman, Claude

    2012-08-01

    Young, old, pregnant and immuno-compromised persons are of great concern for risk assessors as they represent the sub-populations most at risk. The present paper focuses on risk assessment linked to furan exposure in children. Only the Belgian population was considered because individual contamination and consumption data that are required for accurate risk assessment were available for Belgian children only. Two risk assessment approaches, the so-called deterministic and probabilistic, were applied and the results were compared for the estimation of daily intake. A significant difference between the average Estimated Daily Intake (EDI) was underlined between the deterministic (419 ng kg⁻¹ body weight (bw) day⁻¹) and the probabilistic (583 ng kg⁻¹ bw day⁻¹) approaches, which results from the mathematical treatment of the null consumption and contamination data. The risk was characterised by two ways: (1) the classical approach by comparison of the EDI to a reference dose (RfD(chronic-oral)) and (2) the most recent approach, namely the Margin of Exposure (MoE) approach. Both reached similar conclusions: the risk level is not of a major concern, but is neither negligible. In the first approach, only 2.7 or 6.6% (respectively in the deterministic and in the probabilistic way) of the studied population presented an EDI above the RfD(chronic-oral). In the second approach, the percentage of children displaying a MoE above 10,000 and below 100 is 3-0% and 20-0.01% in the deterministic and probabilistic modes, respectively. In addition, children were compared to adults and significant differences between the contamination patterns were highlighted. While major contamination was linked to coffee consumption in adults (55%), no item predominantly contributed to the contamination in children. The most important were soups (19%), dairy products (17%), pasta and rice (11%), fruit and potatoes (9% each). PMID:22632631

  5. Comparison of solid and liquid-phase bioassays using ecoscores to assess contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Lors, Christine [Universite Lille Nord de France, 1bis rue Georges Lefevre, 59044 Lille Cedex (France); Ecole des Mines de Douai, LGCgE-MPE-GCE, 941 rue Charles-Bourseul, 59500 Douai (France); Centre National de Recherche sur les Sites et Sols Pollues, 930 Boulevard Lahure, BP 537, 59505 Douai Cedex (France); Ponge, Jean-Francois, E-mail: ponge@mnhn.fr [Museum National d' Histoire Naturelle, Departement Ecologie et Gestion de la Biodiversite, CNRS UMR 7179, 4 Avenue du Petit-Chateau, 91800 Brunoy (France); Martinez Aldaya, Maite [Museum National d' Histoire Naturelle, Departement Ecologie et Gestion de la Biodiversite, CNRS UMR 7179, 4 Avenue du Petit-Chateau, 91800 Brunoy (France); Damidot, Denis [Universite Lille Nord de France, 1bis rue Georges Lefevre, 59044 Lille Cedex (France); Ecole des Mines de Douai, LGCgE-MPE-GCE, 941 rue Charles-Bourseul, 59500 Douai (France)

    2011-10-15

    Bioassays on aqueous and solid phases of contaminated soils were compared, belonging to a wide array of trophic and response levels and using ecoscores for evaluating ecotoxicological and genotoxicological endpoints. The method was applied to four coke factory soils contaminated mainly with PAHs, but also to a lesser extent by heavy metals and cyanides. Aquatic bioassays do not differ from terrestrial bioassays when scaling soils according to toxicity but they are complementary from the viewpoint of ecological relevance. Both aquatic and terrestrial endpoints are strongly correlated with concentrations of 3-ring PAHs. This evaluation procedure allows us to propose a cost-effective battery which embraces a wide array of test organisms and response levels: it includes two rapid bioassays (Microtox) and springtail avoidance), a micronucleus test and three bioassays of a longer duration (algal growth, lettuce germination and springtail reproduction). This battery can be recommended for a cost-effective assessment of polluted/remediated soils. - Highlights: > Comparison of liquid- and solid-phase bioassays on contaminated soils, using ecoscores. > Complementarity of liquid- and solid-phase bioassays for the evaluation of environmental hazards. > Proposal for a restricted battery of 5 most sensitive tests. > Use of this restricted battery for a cost-effective assessment of polluted/remediated soils. - Aqueous and solid phases of contaminated soils give similar results in terms of toxicity but are complementary for the evaluation of environmental hazards by ecoscores.

  6. Baseline risk assessment of groundwater contamination at the Uranium Mill Tailings Site near Gunnison, Colorado. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-01

    This report evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells to determine the potential for immediate human health and environmental impacts. This risk assessment evaluates the most contaminated groundwater that flows beneath the processing site towards the Gunnison River. The monitor wells that have consistently shown the highest concentration of most contaminants are used in this risk assessment. This risk assessment will be used in conjunction with additional activities and documents to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the groundwater are cadmium, cobalt, iron, manganese, sulfate, uranium, and some of the products of radioactive decay of uranium.

  7. Assessing potential impacts associated with contamination events in water distribution systems : a sensitivity analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Davis, M. J.; Janke, R.; Taxon, T. N. (Decision and Information Sciences); ( EVS); (EPA)

    2010-11-01

    An understanding of the nature of the adverse effects that could be associated with contamination events in water distribution systems is necessary for carrying out vulnerability analyses and designing contamination warning systems. This study examines the adverse effects of contamination events using models for 12 actual water systems that serve populations ranging from about 104 to over 106 persons. The measure of adverse effects that we use is the number of people who are exposed to a contaminant above some dose level due to ingestion of contaminated tap water. For this study the number of such people defines the impact associated with an event. We consider a wide range of dose levels in order to accommodate a wide range of potential contaminants. For a particular contaminant, dose level can be related to a health effects level. For example, a dose level could correspond to the median lethal dose, i.e., the dose that would be fatal to 50% of the exposed population. Highly toxic contaminants may be associated with a particular response at a very low dose level, whereas contaminants with low toxicity may only be associated with the same response at a much higher dose level. This report focuses on the sensitivity of impacts to five factors that either define the nature of a contamination event or involve assumptions that are used in assessing exposure to the contaminant: (1) duration of contaminant injection, (2) time of contaminant injection, (3) quantity or mass of contaminant injected, (4) population distribution in the water distribution system, and (5) the ingestion pattern of the potentially exposed population. For each of these factors, the sensitivities of impacts to injection location and contaminant toxicity are also examined. For all the factors considered, sensitivity tends to increase with dose level (i.e., decreasing toxicity) of the contaminant, with considerable inter-network variability. With the exception of the population distribution (factor 4

  8. Integrated modelling for assessing the risk of TCE groundwater contamination to human and surface water ecosystems

    DEFF Research Database (Denmark)

    McKnight, Ursula S.; Funder, Simon Goltermann; Finkel, Michael; Binning, Philip John; Bjerg, Poul Løgstrup

    2009-01-01

    The practical implementation of the European Water Framework Directive has resulted in an increased focus on the groundwater-surface water interaction zone. Due to increasing global exploitation of both stream water and groundwater resources, a better awareness of the connections between these two...... management tools designed to work with sparse data sets from preliminary site assessments are needed which can explicitly link contaminant point sources with groundwater, surface water and ecological impacts. Here, a novel integrated modelling approach was employed for evaluating the impact of a TCE...... systems and the roles they play in maintaining water quality is essential, as well as on how human activities may impair them. A gap exists with respect to preliminary assessment methodologies that are capable of evaluating and prioritising point sources of contamination. In particular, adaptive...

  9. Feathers as a Tool to Assess Mercury Contamination in Gentoo Penguins: Variations at the Individual Level

    OpenAIRE

    Sara Pedro; Xavier, José C.; Sílvia Tavares; Trathan, Phil N.; Norman Ratcliffe; Paiva, Vitor H.; Renata Medeiros; Eduarda Pereira; Pardal, Miguel A.

    2015-01-01

    Feathers have been widely used to assess mercury contamination in birds as they reflect metal concentrations accumulated between successive moult periods: they are also easy to sample and have minimum impact on the study birds. Moult is considered the major pathway for mercury excretion in seabirds. Penguins are widely believed to undergo a complete, annual moult during which they do not feed. As penguins lose all their feathers, they are expected to have a low individual-variability in feath...

  10. Assessing the human health risks posed by industrially contaminated urban soil : chromium in Glasgow.

    OpenAIRE

    Broadway, A.; Farmer, J G; Ngwenya, B. T.; Cave, M.R.; Fordyce, F.M.

    2005-01-01

    Many cities throughout the UK have a long history of both urbanisation and industrialisation, resulting in elevated concentrations of potentially harmful elements (PHEs) in soils. A recent survey by the British Geological Survey (BGS) of the Glasgow urban environment has highlighted numerous sites with PHE concentrations exceeding guideline values generated by the Contaminated Land Exposure Assessment (CLEA) model. Whether or not these sites pose a hazard to human health depend...

  11. Assessment of water use for estimating exposure to tap water contaminants.

    Science.gov (United States)

    Shimokura, G H; Savitz, D A; Symanski, E

    1998-02-01

    Epidemiological studies examining the association between exposure to tap water contaminants (such as chlorination by-products) and disease outcomes (such as cancer and adverse reproductive outcomes) have been limited by inaccurate exposure assessment. Failure to take into account the variation in beverage and tap water consumption and exposure to volatile contaminants through inhalation and dermal absorption can introduce misclassification in assessing the association between exposure to tap water contaminants and health. To refine exposure assessment of tap water contaminants, we describe in detail the tap water consumption, showering, and bathing habits of pregnant women and their male partners as assessed by a questionnaire and a 3-day water diary. We found good agreement between questionnaire and 3-day water diary values for drinking water intake (Pearson's r = 0.78) and for time spent showering(r = 0.68) and bathing (r = 0.78). Half of the participants consumed tap water on a regular basis with an overall mean +/- 1 standard deviation (SD) of 0. 78 +/- 0.51 l/day. Our results further suggest that full-time employees, compared to women working part-time or less, have more heterogeneous consumption patterns over time. Seventy-nine percent of women and 94% of men took showers for an average of 11.6 +/-4.0 min and 10.4 +/- 4.8 min, respectively. Baths were taken more frequently by women than men (21% vs. 3%) for an average of 22.9 +/-10.1 min and 21.3 +/- 12.4 min, respectively. Thus, these patterns of tap water use should be considered in the design and interpretation of environmental epidemiology studies. PMID:9432970

  12. Assessment of Environmental Contamination and Environmental Decontamination Practices within an Ebola Holding Unit, Freetown, Sierra Leone

    OpenAIRE

    Youkee, Daniel; Brown, Colin S; Lilburn, Paul; Shetty, Nandini; Brooks, Tim; Simpson, Andrew; Bentley, Neil; Lado, Marta; Kamara, Thaim B; Walker, Naomi F.; Johnson, Oliver

    2015-01-01

    Evidence to inform decontamination practices at Ebola holding units (EHUs) and treatment centres is lacking. We conducted an audit of decontamination procedures inside Connaught Hospital EHU in Freetown, Sierra Leone, by assessing environmental swab specimens for evidence of contamination with Ebola virus by RT-PCR. Swabs were collected following discharge of Ebola Virus Disease (EVD) patients before and after routine decontamination. Prior to decontamination, Ebola virus RNA was detected wit...

  13. Contaminants assessment in the coral reefs of Virgin Islands National Park and Virgin Islands Coral Reef National Monument

    Science.gov (United States)

    Bargar, Timothy A.; Garrison, Virginia H.; Alvarez, David A.; Echols, Kathy

    2013-01-01

    Coral, fish, plankton, and detritus samples were collected from coral reefs in Virgin Islands National Park (VIIS) and Virgin Islands Coral Reef National Monument (VICR) to assess existing contamination levels. Passive water sampling using polar organic chemical integrative samplers (POCIS) and semi-permeable membrane devices found a few emerging pollutants of concern (DEET and galaxolide) and polynuclear aromatic hydrocarbons. Very little persistent organic chemical contamination was detected in the tissue or detritus samples. Detected contaminants were at concentrations below those reported to be harmful to aquatic organisms. Extracts from the POCIS were subjected to the yeast estrogen screen (YES) to assess potential estrogenicity of the contaminant mixture. Results of the YES (estrogen equivalency of 0.17–0.31 ng/L 17-β-estradiol) indicated a low estrogenicity likelihood for contaminants extracted from water. Findings point to low levels of polar and non-polar organic contaminants in the bays sampled within VICR and VIIS.

  14. Improving Modeling of Iodine-129 Groundwater Contamination Plumes Using the System Assessment Capability

    International Nuclear Information System (INIS)

    Years of production of radioactive materials at the Hanford Site in southeastern Washington State has resulted in contamination of surface, subsurface, and surface water environments. Cleanup of the site has been aided by various tools, including computer software used to predict contaminant migration in the future and estimate subsequent impacts. The System Assessment Capability (SAC) is a total systems tool designed to simulate the movement of contaminants from all waste sites at Hanford through the vadose zone, the unconfined aquifer, and the Columbia River. Except for iodine-129, most of the contaminants modeled by SAC have acceptably matched field measurements. The two most likely reasons for the inconsistency between the measured field data and SAC modeled predictions are an underestimated inventory and an overestimated sorption value (Kd). Field data tend to be point measurements taken from near the surface of the unconfined aquifer. Thus, the depth of the iodine-129 contamination plume on the site is not well characterized. Geostatistical analyses of the measured data were conducted to determine the mass of iodine-129 for four assumed plume depths within the unconfined aquifer. Several simulations for two different Kd's using the initial SAC inventory were run to determine the effect of an overestimated sorption value on SAC modeled predictions. The initial SAC inventory was then increased for the two different Kd's to determine the influence of an underestimated inventory on SAC modeled predictions. It was found that evidence for both an underestimated inventory and for an overestimated sorption value for iodine-129 exist. These results suggest that the Kd for iodine-129 should be reevaluated and that a more complete inventory must be generated in order to more accurately model iodine-129 groundwater contamination plumes that match available field data

  15. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Grand Junction, Colorado

    International Nuclear Information System (INIS)

    This Baseline Risk Assessment of Ground Water Contamination at the Uranium Mill Tailings Site Near Grand Junction, Colorado evaluates potential impacts to public health or the environment resulting from ground water contamination at the former uranium mill processing site. The tailings and other contaminated material at this site were placed in an off-site disposal cell by the US Department of Energy's (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. The remedial activities at the site were conducted from 1989 to 1993. Currently, the UMTRA Project is evaluating ground water contamination. This risk assessment is the first document specific to this site for the Ground Water Project. This risk assessment evaluates the most contaminated ground water that flows beneath the processing site toward the Colorado River. The monitor wells that have consistently shown the highest concentrations of most contaminants are used to assess risk. This risk assessment will be used in conjunction with additional activities and documents to determine what remedial action may be needed for contaminated ground water at the site. This risk assessment follows an approach outlined by the EPA. the first step is to evaluate ground water data collected from monitor wells at the site. Evaluation of these data showed that the contaminants of potential concern in the ground water are arsenic, cadmium, cobalt, fluoride, iron, manganese, molybdenum, nickel, sulfate, uranium, vanadium, zinc, and radium-226. The next step in the risk assessment is to estimate how much of these contaminants people would be exposed to if they drank from a well installed in the contaminated ground water at the former processing site

  16. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Grand Junction, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    This Baseline Risk Assessment of Ground Water Contamination at the Uranium Mill Tailings Site Near Grand Junction, Colorado evaluates potential impacts to public health or the environment resulting from ground water contamination at the former uranium mill processing site. The tailings and other contaminated material at this site were placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. The remedial activities at the site were conducted from 1989 to 1993. Currently, the UMTRA Project is evaluating ground water contamination. This risk assessment is the first document specific to this site for the Ground Water Project. This risk assessment evaluates the most contaminated ground water that flows beneath the processing site toward the Colorado River. The monitor wells that have consistently shown the highest concentrations of most contaminants are used to assess risk. This risk assessment will be used in conjunction with additional activities and documents to determine what remedial action may be needed for contaminated ground water at the site. This risk assessment follows an approach outlined by the EPA. the first step is to evaluate ground water data collected from monitor wells at the site. Evaluation of these data showed that the contaminants of potential concern in the ground water are arsenic, cadmium, cobalt, fluoride, iron, manganese, molybdenum, nickel, sulfate, uranium, vanadium, zinc, and radium-226. The next step in the risk assessment is to estimate how much of these contaminants people would be exposed to if they drank from a well installed in the contaminated ground water at the former processing site.

  17. A System Dynamics Approach for the Integrative Assessment of Contaminated Land Management Options

    DEFF Research Database (Denmark)

    McKnight, Ursula S.; Finkel, Michael

    Remediation Options) designed to facilitate the establishment of appropriate, cost-effective management schemes for achieving site-specific remediation objectives within reasonable timeframes. Preliminary assessment shall quickly provide reasonable estimates of current and future risks, as well as of the...... contamination extent, boundary conditions/limitations, stakeholders, etc.) has led to the proposal of tiered frameworks for site investigation, risk assessment and management, e.g. in the United Kingdom and in the USA. Recent policies request an increased emphasis on modelling (e.g. EU Water Framework Directive...... costs of possible remediation (risk reduction) strategies....

  18. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Green River, Utah

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    This document evaluates potential impacts to public health and the environment resulting from ground water contamination at the former uranium mill processing site. The tailings and other contaminated material at this site were placed in a disposal cell on the site in 1989 by the US DOE`s Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, UMTRA Project is evaluating ground water contamination in this risk assessment.

  19. Incorporation of Socio-Cultural Values in Damage Assessment Valuations of Contaminated Lands in the Niger Delta

    OpenAIRE

    Victor A. Akujuru; Les Ruddock

    2014-01-01

    Damages on contaminated land have been mostly assessed for developments subsisting on the land, neglecting the goods and services derived from the land which possess only socio-cultural values. This paper aims to ascertain the importance of socio-cultural values in the total economic value of contaminated land, drawing from the experience of a coastal community oil spillage in the Niger Delta. The paper examines what constitutes a valuable interest on contaminated land and how socio-cultural...

  20. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Sites near Slick Rock, Colorado. Revision 1

    International Nuclear Information System (INIS)

    Two UMTRA (Uranium Mill Tailings Remedial Action) Project sites are near Slick Rock, Colorado: the North Continent site and the Union Carbide site. Currently, no one uses the contaminated ground water at either site for domestic or agricultural purposes. However, there may be future land development. This risk assessment evaluates possible future health problems associated with exposure to contaminated ground water. Since some health problems could occur, it is recommended that the contaminated ground water not be used as drinking water

  1. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Green River, Utah

    International Nuclear Information System (INIS)

    This document evaluates potential impacts to public health and the environment resulting from ground water contamination at the former uranium mill processing site. The tailings and other contaminated material at this site were placed in a disposal cell on the site in 1989 by the US DOE's Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, UMTRA Project is evaluating ground water contamination in this risk assessment

  2. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Sites near Slick Rock, Colorado. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    Two UMTRA (Uranium Mill Tailings Remedial Action) Project sites are near Slick Rock, Colorado: the North Continent site and the Union Carbide site. Currently, no one uses the contaminated ground water at either site for domestic or agricultural purposes. However, there may be future land development. This risk assessment evaluates possible future health problems associated with exposure to contaminated ground water. Since some health problems could occur, it is recommended that the contaminated ground water not be used as drinking water.

  3. Bacterial Community Diversity of Oil-Contaminated Soils Assessed by High Throughput Sequencing of 16S rRNA Genes

    OpenAIRE

    Mu Peng; Xiaoxue Zi; Qiuyu Wang

    2015-01-01

    Soil bacteria play a major role in ecological and biodegradable function processes in oil-contaminated soils. Here, we assessed the bacterial diversity and changes therein in oil-contaminated soils exposed to different periods of oil pollution using 454 pyrosequencing of 16S rRNA genes. No less than 24,953 valid reads and 6246 operational taxonomic units (OTUs) were obtained from all five studied samples. OTU richness was relatively higher in contaminated soils than clean samples. Acidobacte...

  4. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Shiprock, New Mexico. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-01

    This baseline risk assessment at the former uranium mill tailings site near Shiprock, New Mexico, evaluates the potential impact to public health or the environment resulting from ground water contamination at the former uranium mill processing site. The tailings and other contaminated material at this site were placed in an on-site disposal cell in 1986 through the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating ground water contamination. This risk assessment is the first document specific to this site for the Ground Water Project. There are no domestic or drinking water wells in the contaminated ground water of the two distinct ground water units: the contaminated ground water in the San Juan River floodplain alluvium below the site and the contaminated ground water in the terrace alluvium area where the disposal cell is located. Because no one is drinking the affected ground water, there are currently no health or environmental risks directly associated with the contaminated ground water. However, there is a potential for humans, domestic animals, and wildlife to the exposed to surface expressions of ground water in the seeps and pools in the area of the San Juan River floodplain below the site. For these reasons, this risk assessment evaluates potential exposure to contaminated surface water and seeps as well as potential future use of contaminated ground water.

  5. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Shiprock, New Mexico

    International Nuclear Information System (INIS)

    This baseline risk assessment at the former uranium mill tailings site near Shiprock, New Mexico, evaluates the potential impact to public health or the environment resulting from ground water contamination at the former uranium mill processing site. The tailings and other contaminated material at this site were placed in an on-site disposal cell in 1986 through the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating ground water contamination. This risk assessment is the first document specific to this site for the Ground Water Project. There are no domestic or drinking water wells in the contaminated ground water of the two distinct ground water units: the contaminated ground water in the San Juan River floodplain alluvium below the site and the contaminated ground water in the terrace alluvium area where the disposal cell is located. Because no one is drinking the affected ground water, there are currently no health or environmental risks directly associated with the contaminated ground water. However, there is a potential for humans, domestic animals, and wildlife to the exposed to surface expressions of ground water in the seeps and pools in the area of the San Juan River floodplain below the site. For these reasons, this risk assessment evaluates potential exposure to contaminated surface water and seeps as well as potential future use of contaminated ground water

  6. Characterization and Remediation of Contaminated Sites:Modeling, Measurement and Assessment

    Science.gov (United States)

    Basu, N. B.; Rao, P. C.; Poyer, I. C.; Christ, J. A.; Zhang, C. Y.; Jawitz, J. W.; Werth, C. J.; Annable, M. D.; Hatfield, K.

    2008-05-01

    small computation time and their inclusion of spatially integrated parameters that can be measured in the field using tracer tests. Analytical models that couple source depletion to plume transport were used for optimization of source and plume treatment. These models are being used for the development of decision and management tools (for DNAPL sites) that consider uncertainty assessments as an integral part of the decision-making process for contaminated site remediation.

  7. Assessing the potential of brachiaria decumbens as remediation agent for soil contaminated wit oil sludge

    International Nuclear Information System (INIS)

    Bioremediation is a method of treatment of soil or water contaminated with toxic materials, involving the use of living organisms. Oil or petroleum sludge is a waste product of the petroleum refining industry, and is now accumulating at a fast rate at petroleum refinery sites in the country. Common components of oil sludge are mud and sand, containing toxic materials from hydrocarbons, heavy metals and radioactive elements from the seabed. In the present study, the oil sludge samples were obtained from barrels of the materials stored at the Radioactive Waste Treatment Centre, MINT. The samples were analysed of their compounds, elemental and radioactive contents. Trials on microbial degradation of the sludge materials were ongoing. This paper discusses the potential of a grass to remediate soils contaminated with petroleum sludge. Remediation of soils contaminated with organic compounds and heavy metals using plants, including grasses, including Vetiver, Lolium and Agrostis have been carried out in many countries. A greenhouse pot trial was conducted to assess the suitability of the pasture grass Brachiaria decumbens Stapf. and its mutant Brachiaria decumbens KLUANG Comel as a remediation agent for oil sludge contaminated soil. Samples of grasses and soils before planting, during growth stage and at end of experiment were analysed for the different toxicity. Although the grasses were promoted for use in pasture, and KLUANG Comel has good potential as an ornamental plant, too, their other potentials, including as phytoremediation agents need to be explored. (Author)

  8. Assessing spatial variability of soil petroleum contamination using visible near-infrared diffuse reflectance spectroscopy.

    Science.gov (United States)

    Chakraborty, Somsubhra; Weindorf, David C; Zhu, Yuanda; Li, Bin; Morgan, Cristine L S; Ge, Yufeng; Galbraith, John

    2012-11-01

    Visible near-infrared (VisNIR) diffuse reflectance spectroscopy (DRS) is a rapid, non-destructive method for sensing the presence and amount of total petroleum hydrocarbon (TPH) contamination in soil. This study demonstrates the feasibility of VisNIR DRS to be used in the field to proximally sense and then map the areal extent of TPH contamination in soil. More specifically, we evaluated whether a combination of two methods, penalized spline regression and geostatistics could provide an efficient approach to assess spatial variability of soil TPH using VisNIR DRS data from soils collected from an 80 ha crude oil spill in central Louisiana, USA. Initially, a penalized spline model was calibrated to predict TPH contamination in soil by combining lab TPH values of 46 contaminated and uncontaminated soil samples and the first-derivative of VisNIR reflectance spectra of these samples. The r(2), RMSE, and bias of the calibrated penalized spline model were 0.81, 0.289 log(10) mg kg(-1), and 0.010 log(10) mg kg(-1), respectively. Subsequently, the penalized spline model was used to predict soil TPH content for 128 soil samples collected over the 80 ha study site. When assessed with a randomly chosen validation subset (n = 10) from the 128 samples, the penalized spline model performed satisfactorily (r(2) = 0.70; residual prediction deviation = 2.0). The same validation subset was used to assess point kriging interpolation after the remaining 118 predictions were used to produce an experimental semivariogram and map. The experimental semivariogram was fitted with an exponential model which revealed strong spatial dependence among soil TPH [r(2) = 0.76, nugget = 0.001 (log(10) mg kg(-1))(2), and sill 1.044 (log(10) mg kg(-1))(2)]. Kriging interpolation adequately interpolated TPH with r(2) and RMSE values of 0.88 and 0.312 log(10) mg kg(-1), respectively. Furthermore, in the kriged map, TPH distribution matched with the expected TPH variability of the study site. Since the

  9. Human health risk assessment in restoring safe and productive use of abandoned contaminated sites.

    Science.gov (United States)

    Wcisło, Eleonora; Bronder, Joachim; Bubak, Anicenta; Rodríguez-Valdés, Eduardo; Gallego, José Luis R

    2016-09-01

    In Europe soil contamination has been recognized as a serious problem. The needs to remediate contaminated sites are not questionable, although the remediation actions are often hindered by their very high financial costs. On the other hand, the abandoned contaminated sites may have the potential for redevelopment and creating conditions appropriate for their productive reuse bringing social, economic and environmental benefits. The main concern associated with the contaminated sites is their potential adverse health impact. Therefore, in the process of contaminated site redevelopment the risk assessment and the subsequent risk management decisions will play a crucial role. The main objective of this study was to illustrate the role of the human health risk assessment (HRA) in supporting site remediation and reuse decisions. To exemplify the significance of the HRA process in this field the Nitrastur site, located in Asturias, Spain was used. Risks resulting from soil contamination with arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), mercury (Hg), zinc (Zn) and lead (Pb) were assessed under three potential future land use patterns: industrial, residential and recreational. The results of the study indicated that soil at the Nitrastur site might pose non-cancer and cancer risks to potential future receptors - industrial workers, residents and recreational users. Arsenic and lead are the main substances responsible for the health risk and the primary drivers of remedial decisions at the site. The highest total cancer risks were observed under the residential scenario, followed in descending order by the recreational and industrial ones. The remedial maps illustrate in which areas remediation activities are required, depending on a given land use pattern. The obtained results may be used to develop, analyse, compare and select the remedial options within the intended land use pattern. They may also be used to support the decisions concerning the

  10. Cancer and non-cancer health effects from food contaminant exposures for children and adults in California: a risk assessment

    OpenAIRE

    Vogt Rainbow; Bennett Deborah; Cassady Diana; Frost Joshua; Ritz Beate; Hertz-Picciotto Irva

    2012-01-01

    Abstract Background In the absence of current cumulative dietary exposure assessments, this analysis was conducted to estimate exposure to multiple dietary contaminants for children, who are more vulnerable to toxic exposure than adults. Methods We estimated exposure to multiple food contaminants based on dietary data from preschool-age children (2–4 years, n=207), school-age children (5–7 years, ...

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

    Science.gov (United States)

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

    2010-12-01

    The environmental impacts of remediation of a chloroethene-contaminated site were evaluated using life cycle assessment (LCA). The compared remediation options are (i) in situ bioremediation by enhanced reductive dechlorination (ERD), (ii) in situ thermal desorption (ISTD), and (iii) excavation of the contaminated soil followed by off-site treatment and disposal. The results showed that choosing the ERD option will reduce the life-cycle impacts of remediation remarkably compared to choosing either ISTD or excavation, which are more energy-demanding. In addition to the secondary impacts of remediation, this study includes assessment of local toxic impacts (the primary impact) related to the on-site contaminant leaching to groundwater and subsequent human exposure via drinking water. The primary human toxic impacts were high for ERD due to the formation and leaching of chlorinated degradation products, especially vinyl chloride during remediation. However, the secondary human toxic impacts of ISTD and excavation are likely to be even higher, particularly due to upstream impacts from steel production. The newly launched model, USEtox, was applied for characterization of primary and secondary toxic impacts and combined with a site-dependent fate model of the leaching of chlorinated ethenes from the fractured clay till site. PMID:21053954

  12. Assessment of metals contamination and ecological risk in ait Ammar abandoned iron mine soil, Morocco

    Directory of Open Access Journals (Sweden)

    Nouri Mohamed

    2016-03-01

    Full Text Available The present study is an attempt to assess the pollution intensity and corresponding ecological risk of phosphorus and metals including Cd, Cr, Cu, Zn, Pb and Fe using various indices like geo-accumulation index, enrichment factor, pollution and ecological risk index. In all, 20 surface soil samples were collected from the Ait Ammar iron mine of Oued Zem city, province of Khouribga, in central Morocco. The concentrations of heavy metals in soil samples were used to assess their potential ecological risks. According to the results of potential ecological risk index (RI, pollution index (PI, geo-accumulation index (Igeo, enrichment factor (EF, potential contamination index (Cp, contaminant factor (Cf and degree of contamination (Cd, based on the averages, considerable pollution of metals in soils of study area was observed. The consequence of the correlation matrix and principal component analysis (PCA indicated that Fe, Cu, Zn, Cr and P mainly originated from natural sources and Cd and Pb are mostly derived from anthropogenic sources. The results showed that these metals in soil were ranked by severity of ecological risk as Pb > Cd > Cu > Cr > Zn, based on their single-element indexes. In view of the potential ecological risk (RI, soils from all soil samples showed a potential ecological risk. These results will provide basic information for the improvement of soil environment management and heavy metal pollution prevention in Ait Ammar.

  13. Terrestrial avoidance behaviour tests as screening tool to assess soil contamination

    International Nuclear Information System (INIS)

    To assess soil quality and risk assessment, bioassays can be useful tools to gauge the potential toxicity of contaminants focusing on their bioavailable fraction. A rapid and sublethal avoidance behaviour test was used as a screening tool with the earthworm Eisenia andrei and the isopod Porcellionides pruinosus, where organisms were exposed during 48 h to several chemicals (lindane, dimethoate and copper sulphate, for isopods and carbendazim, benomyl, dimethoate and copper sulphate for earthworms). Both species were also exposed to soils from an abandoned mine. For all bioassays a statistical approach was used to derive EC50 values. Isopods and earthworms were able to perceive the presence of toxic compounds and escaping from contaminated to clean soil. Furthermore the behaviour parameter was equally or more sensitive then other sublethal parameters (e.g. reproduction or growth), expressing the advantages of Avoidance Behaviour Tests as screening tools in ERA. - Avoidance Behaviour Tests with earthworms and isopods can be used as screening tools in the evaluation of soil contamination

  14. A Stochastic Approach To Human Health Risk Assessment Due To Groundwater Contamination

    Science.gov (United States)

    de Barros, F. P.; Rubin, Y.

    2006-12-01

    We present a probabilistic framework to addressing adverse human health effects due to groundwater contamination. One of the main challenges in health risk assessment is in relating it to subsurface data acquisition and to improvement in our understanding of human physiological responses to contamination. In this paper we propose to investigate this problem through an approach that integrates flow, transport and human health risk models with hydrogeological characterization. A human health risk cumulative distribution function is analytically developed to account for both uncertainty and variability in hydrogeological as well as human physiological parameters. With our proposed approach, we investigate under which conditions the reduction of uncertainties from flow physics, human physiology and exposure related parameters might contribute to a better understanding of human health risk assessment. Results indicate that the human health risk cumulative distribution function is sensitive to physiological parameters at low risk values associated with longer travel times. The results show that the worth of hydrogeological characterization in human health risk is dependent on the residence time of the contaminant plume in the aquifer and on the exposure duration of the population to certain chemicals.

  15. Terrestrial avoidance behaviour tests as screening tool to assess soil contamination

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, Susana [Department of Biology, University of Aveiro, 3810-193 Aveiro (Portugal)]. E-mail: sloureiro@bio.ua.pt; Soares, Amadeu M.V.M. [Department of Biology, University of Aveiro, 3810-193 Aveiro (Portugal); Nogueira, Antonio J.A. [Department of Biology, University of Aveiro, 3810-193 Aveiro (Portugal)

    2005-11-15

    To assess soil quality and risk assessment, bioassays can be useful tools to gauge the potential toxicity of contaminants focusing on their bioavailable fraction. A rapid and sublethal avoidance behaviour test was used as a screening tool with the earthworm Eisenia andrei and the isopod Porcellionides pruinosus, where organisms were exposed during 48 h to several chemicals (lindane, dimethoate and copper sulphate, for isopods and carbendazim, benomyl, dimethoate and copper sulphate for earthworms). Both species were also exposed to soils from an abandoned mine. For all bioassays a statistical approach was used to derive EC{sub 50} values. Isopods and earthworms were able to perceive the presence of toxic compounds and escaping from contaminated to clean soil. Furthermore the behaviour parameter was equally or more sensitive then other sublethal parameters (e.g. reproduction or growth), expressing the advantages of Avoidance Behaviour Tests as screening tools in ERA. - Avoidance Behaviour Tests with earthworms and isopods can be used as screening tools in the evaluation of soil contamination.

  16. Radon as a naturally occurring tracer for the assessment of residual NAPL contamination of aquifers

    International Nuclear Information System (INIS)

    The noble gas radon has a strong affinity to non-aqueous phase-liquids (NAPLs). That property makes it applicable as naturally occurring partitioning tracer for assessing residual NAPL contamination of aquifers. In a NAPL contaminated aquifer, radon dissolved in the groundwater partitions preferably into the NAPL. The magnitude of the resulting radon deficit in the groundwater depends on the NAPL-specific radon partition coefficient and on the NAPL saturation of the pore space. Hence, if the partition coefficient is known, the NAPL saturation is attainable by determination of the radon deficit. After a concise discussion of theoretical aspects regarding radon partitioning into NAPL, related experimental data and results of a field investigation are presented. Aim of the laboratory experiments was the determination of radon partition coefficients of multi-component NAPLs of environmental concern. The on-site activities were carried out in order to confirm the applicability of the 'radon method' under field conditions. - The paper presents the theoretical concept and experimental results which confirm the applicability of naturally occurring radon for assessing residual NAPL contamination of aquifers

  17. Radon as a naturally occurring tracer for the assessment of residual NAPL contamination of aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, Michael [UFZ Centre for Environmental Research, Permoserstrasse 15, 04318 Leipzig (Germany)]. E-mail: michael.schubert@ufz.de; Paschke, Albrecht [UFZ Centre for Environmental Research, Permoserstrasse 15, 04318 Leipzig (Germany); Lau, Steffen [UFZ Centre for Environmental Research, Permoserstrasse 15, 04318 Leipzig (Germany); Geyer, Wolfgang [UFZ Centre for Environmental Research, Permoserstrasse 15, 04318 Leipzig (Germany); Knoeller, Kay [UFZ Centre for Environmental Research, Permoserstrasse 15, 04318 Leipzig (Germany)

    2007-02-15

    The noble gas radon has a strong affinity to non-aqueous phase-liquids (NAPLs). That property makes it applicable as naturally occurring partitioning tracer for assessing residual NAPL contamination of aquifers. In a NAPL contaminated aquifer, radon dissolved in the groundwater partitions preferably into the NAPL. The magnitude of the resulting radon deficit in the groundwater depends on the NAPL-specific radon partition coefficient and on the NAPL saturation of the pore space. Hence, if the partition coefficient is known, the NAPL saturation is attainable by determination of the radon deficit. After a concise discussion of theoretical aspects regarding radon partitioning into NAPL, related experimental data and results of a field investigation are presented. Aim of the laboratory experiments was the determination of radon partition coefficients of multi-component NAPLs of environmental concern. The on-site activities were carried out in order to confirm the applicability of the 'radon method' under field conditions. - The paper presents the theoretical concept and experimental results which confirm the applicability of naturally occurring radon for assessing residual NAPL contamination of aquifers.

  18. Environmental impact assessment: Classification of ecosystems with respect to vulnerability for radioactive contamination

    International Nuclear Information System (INIS)

    This presentation recommends that an environmental impact assessment should be made ahead of any major action plan in the environment. The final document should point out to the authorities and public that expertise has been systematised in order to predict the effects of an action plan on the environment. This should be done for different scenarios and time scales. A useful tool for an environmental impact assessment is GIS, Geographic Information Systems. It can be used to identify areas and ecosystems that are vulnerable to radioactive contamination. To predict the radiation dose to humans and biota, a vulnerability assessment considers population density, land use, economic resources and the chemical and biological pathways of radionuclides in different ecosystems. Supplemented with knowledge of consumption and dietary habits a vulnerability assessment can be used to identify critical groups and to calculate doses to these groups. For ecosystems, vulnerability can be quantified by using critical loads for radioactive contamination or flux of radionuclides from an area. One criterion for critical load can be that intervention limits for food products should not be exceeded. If the critical load is low, this indicates a high vulnerability. The flux from an area can also identify vulnerability and it can be used to calculate collective dose. The vulnerability approach is a methodology that can be used to select areas that are suitable for treatment, transport and disposal of radioactive waste

  19. Long-term assessment of contaminated articles from the Chernobyl reactor

    International Nuclear Information System (INIS)

    The Chernobyl accident caused a release of radioactive materials from the reactor into the environment. This event contaminated people, their surroundings and their personal property, especially in the zone around the reactor. Among the affected individuals were British students who were studying in Minsk and Kiev at the time of the Chernobyl accident. These students were exposed to external and internal radiation, and the individuals' articles of clothing were contaminated. The primary objective of this study was to analyze a sample of this contaminated clothing 20 years after the accident using three different detectors, namely, a BP4/4C scintillation detector, a Min-Con Geiger-Müller tube detector and a high-purity germanium (HPGe) detector. The clothing articles were initially assessed and found not to be significantly contaminated. However, there were several hot spots of contamination in various regions of the articles. The net count rates for these hot spots were in the range of 10.00 ± 3.16 c/s to 41.00 ± 6.40 c/s when the BP4/4C scintillation detector was used. The HPGe detector was used to identify the radionuclides present in the clothing, and the results indicated that the only active radionuclide was 137Cs because of this isotope's long half-life. - Highlights: • The study highlights the effect of radionuclide half-life on the uncertainty of the pollution measurement. • Most of the observed radionuclides 20 years ago have now disappeared due the decay effect. • The study shows improvements in radiation detectors by detecting very low activities of isotopes not measured 20 years ago

  20. Risk assessment of coccidostatics during feed cross-contamination: Animal and human health aspects

    International Nuclear Information System (INIS)

    Coccidiosis, an intestinal plasmodium infection, is a major infectious disease in poultry and rabbits. Eleven different coccidiostats are licensed in the EU for the prevention of coccidiosis in these animal species. According to their chemical nature and main biological activity, these compounds can be grouped as ionophoric (monensin, lasalocid sodium, salinomycin, narasin, maduramicin and semduramicin) or non-ionophoric (robenidine, decoquinate, nicarbazin, diclazuril, and halofuginone) substances. Coccidiostats are used as feed additives, mixed upon request into the compounded feed. During the technical process of commercial feed production, cross-contamination of feed batches can result in the exposure of non-target animals and induce adverse health effects in these animals due to a specific sensitivity of mammalian species as compared to poultry. Residue formation in edible tissues of non-target species may result in unexpected human exposure through the consumption of animal products. This review presents recent risk assessments performed by the Scientific Panel on Contaminants in the Food Chain (CONTAM) of the European Food Safety Authority (EFSA). The health risk to non-target species that would result from the consumption of cross-contaminated feed with coccidostats at levels of 2, 5 or 10% was found to be negligible for most animal species with the exception of salinomycin and monensin in horses because of the particular sensitivity for which toxicity may occur when cross-contamination exceeds 2% and 5% respectively. Kinetic data and tissue analyses showed that residues of coccidiostats may occur in the liver and eggs in some cases. However, the level of residues of each coccidiostat in edible animal tissues remained sufficiently low that the aggregate exposure of consumers would not exceed the established acceptable daily intake (ADI) of each coccidiostat. It could be concluded that technical cross-contamination of animal feeds would not be expected to

  1. Risk assessment of coccidostatics during feed cross-contamination: Animal and human health aspects

    Energy Technology Data Exchange (ETDEWEB)

    Dorne, J.L.C.M., E-mail: jean-lou.dorne@efsa.europa.eu [European Food Safety Authority, Unit on Contaminants in the Food Chain, Parma (Italy); Fernández-Cruz, M.L. [Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid (Spain); Bertelsen, U. [European Food Safety Authority, Unit on Contaminants in the Food Chain, Parma (Italy); Renshaw, D.W. [Food Standards Agency, London (United Kingdom); Peltonen, K. [Finnish Food Safety Authority, EVIRA, Helsinki (Finland); Anadon, A. [Universidad Complutense de Madrid, Facultad de Veterinaria, Madrid (Spain); Feil, A. [ForschungsinstitutFuttermitteltechnik, Braunschweig (Germany); Sanders, P. [AFSSA, LERMVD, Fougères (France); Wester, P. [RIVM, Food and Consumer Safety, Bilthoven (Netherlands); Fink-Gremmels, J. [Utrecht University, Veterinary Medicine, Utrecht (Netherlands)

    2013-08-01

    Coccidiosis, an intestinal plasmodium infection, is a major infectious disease in poultry and rabbits. Eleven different coccidiostats are licensed in the EU for the prevention of coccidiosis in these animal species. According to their chemical nature and main biological activity, these compounds can be grouped as ionophoric (monensin, lasalocid sodium, salinomycin, narasin, maduramicin and semduramicin) or non-ionophoric (robenidine, decoquinate, nicarbazin, diclazuril, and halofuginone) substances. Coccidiostats are used as feed additives, mixed upon request into the compounded feed. During the technical process of commercial feed production, cross-contamination of feed batches can result in the exposure of non-target animals and induce adverse health effects in these animals due to a specific sensitivity of mammalian species as compared to poultry. Residue formation in edible tissues of non-target species may result in unexpected human exposure through the consumption of animal products. This review presents recent risk assessments performed by the Scientific Panel on Contaminants in the Food Chain (CONTAM) of the European Food Safety Authority (EFSA). The health risk to non-target species that would result from the consumption of cross-contaminated feed with coccidostats at levels of 2, 5 or 10% was found to be negligible for most animal species with the exception of salinomycin and monensin in horses because of the particular sensitivity for which toxicity may occur when cross-contamination exceeds 2% and 5% respectively. Kinetic data and tissue analyses showed that residues of coccidiostats may occur in the liver and eggs in some cases. However, the level of residues of each coccidiostat in edible animal tissues remained sufficiently low that the aggregate exposure of consumers would not exceed the established acceptable daily intake (ADI) of each coccidiostat. It could be concluded that technical cross-contamination of animal feeds would not be expected to

  2. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Tuba City, Arizona

    International Nuclear Information System (INIS)

    This document evaluates potential public health or environmental impacts resulting from ground water contamination at the former uranium mill site. The tailings and other contaminated material at this site were placed in a disposal cell on the site in 1990 by the US Department of Energy's Uranium Mill Tailings Remedial Action (UMTRA) Project. The second phase of the UMTRA Project is to evaluate ground water contamination. This risk assessment is the first site-specific document under the Ground Water Project. It will help determine what remedial actions are necessary for contaminated ground water at the site

  3. Risk assessment of contaminated soil by radionuclides with consideration of foods

    International Nuclear Information System (INIS)

    Risk assessment of soil contaminated with radionuclides due to the accident of Fukushima nuclear power plant after the earthquake on March 11, 2011, carried out by considering the contaminated food. The exposure routes are set as (1) food intake, (2) ingestion and inhalation of soil particles, and (3) external radiation from the ground. As a result, exposures by ingestion and inhalation of soil particles were negligible, and exposure by food intake and external exposure from the ground were large. On the other hand, five food products, whose criteria were set using an acceptable radiation of 5 mSv/yr. In this study, 1 mSv/yr, which is equivalent to 5 x 10-5 of excess cancer risk, was calculated equivalent to 0.2 μSv/hr in air dose in considers of infants; therefore, the value is recommended as the standard. (author)

  4. State of the art of contaminated site management in The Netherlands: Policy framework and risk assessment tools

    Energy Technology Data Exchange (ETDEWEB)

    Swartjes, F.A., E-mail: frank.swartjes@rivm.nl; Rutgers, M.; Lijzen, J.P.A.; Janssen, P.J.C.M.; Otte, P.F.; Wintersen, A.; Brand, E.; Posthuma, L.

    2012-06-15

    This paper presents the policy framework of contaminated site management in The Netherlands and the corresponding risk assessment tools, including innovations that have taken place since an overview was published in 1999. According to the Dutch Soil Protection Act assessment framework, soils are subdivided into three quality classes: clean, slightly contaminated and seriously contaminated. Historic cases of slightly contaminated soils are managed in a sustainable way by re-use of soil material within a region on the basis of risk-based and land use specific Maximal Values and Background Values. In case of serious soil contamination remediation is in principle necessary and the urgency of remediation has to be determined based on site-specific risks for human health, the ecosystem and groundwater. The major risk assessment tools in The Netherlands are the CSOIL exposure model (human health risks and food safety), Species Sensitivity Distributions and the Soil Quality Triad (ecological risks), along with a procedure to assess the risks due to contaminant spreading to and in the groundwater. Following the principle 'simple if possible, complex when necessary', tiered approaches are used. Contaminated site practices are supported with web-based decision support systems. - Highlights: Black-Right-Pointing-Pointer The Dutch Soil Protection Act distinguishes three quality classes: clean, slightly contaminated and seriously contaminated. Black-Right-Pointing-Pointer Serious soil contamination in principle compels remediation and the determination of the urgency of remediation. Black-Right-Pointing-Pointer The relevant protection targets in The Netherlands are human health, ecosystems, groundwater and food safety. Black-Right-Pointing-Pointer Important risk assessment tools are the CSOIL and VOLASOIL exposure models, SSDs and the TRIAD approach. Black-Right-Pointing-Pointer Under the principle 'simple when possible, complex when necessary' tiered

  5. State of the art of contaminated site management in The Netherlands: Policy framework and risk assessment tools

    International Nuclear Information System (INIS)

    This paper presents the policy framework of contaminated site management in The Netherlands and the corresponding risk assessment tools, including innovations that have taken place since an overview was published in 1999. According to the Dutch Soil Protection Act assessment framework, soils are subdivided into three quality classes: clean, slightly contaminated and seriously contaminated. Historic cases of slightly contaminated soils are managed in a sustainable way by re-use of soil material within a region on the basis of risk-based and land use specific Maximal Values and Background Values. In case of serious soil contamination remediation is in principle necessary and the urgency of remediation has to be determined based on site-specific risks for human health, the ecosystem and groundwater. The major risk assessment tools in The Netherlands are the CSOIL exposure model (human health risks and food safety), Species Sensitivity Distributions and the Soil Quality Triad (ecological risks), along with a procedure to assess the risks due to contaminant spreading to and in the groundwater. Following the principle ‘simple if possible, complex when necessary’, tiered approaches are used. Contaminated site practices are supported with web-based decision support systems. - Highlights: ► The Dutch Soil Protection Act distinguishes three quality classes: clean, slightly contaminated and seriously contaminated. ► Serious soil contamination in principle compels remediation and the determination of the urgency of remediation. ► The relevant protection targets in The Netherlands are human health, ecosystems, groundwater and food safety. ► Important risk assessment tools are the CSOIL and VOLASOIL exposure models, SSDs and the TRIAD approach. ► Under the principle ‘simple when possible, complex when necessary’ tiered approaches are used.

  6. Incorporation of Socio-Cultural Values in Damage Assessment Valuations of Contaminated Lands in the Niger Delta

    Directory of Open Access Journals (Sweden)

    Victor A. Akujuru

    2014-07-01

    Full Text Available Damages on contaminated land have been mostly assessed for developments subsisting on the land, neglecting the goods and services derived from the land which possess only socio-cultural values. This paper aims to ascertain the importance of socio-cultural values in the total economic value of contaminated land, drawing from the experience of a coastal community oil spillage in the Niger Delta. The paper examines what constitutes a valuable interest on contaminated land and how socio-cultural factors are valued in the damage assessment process. After reviewing the literature and decided cases, a questionnaire survey was conducted and a sample valuation report was analysed. It is concluded that there exists a socio-cultural interest on contaminated land which professional valuers do not reflect in damage assessment claims. It is recommended that any comprehensive damage assessment requires the incorporation of socio-cultural values in the valuations.

  7. Assessment of Contaminants in the Wetlands and Open Waters of the Great Salt Lake, Utah, 1996-2000

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 1996 and 1997, the United States Fish and Wildlife Service (Service) Utah Field Office undertook a comprehensive assessment of contaminants at over 30 wetland...

  8. Assessment of the contaminants level in recycled aggregates and alternative new technologies for contaminants recognition and removal

    OpenAIRE

    S. Lotfi; Di Maio, F.; Xia, H; Serranti, S.; Palmieri, R.; Bonifazi, G.

    2015-01-01

    One of the main challenging problems associated with the use of Recycled Aggregates (RA) is the level of mixed contaminants. For utilizing RA in high-grade applications, it is essential to monitor and minimise the content of the pollutants. To this extent the C2CA concrete recycling process investigates a combination of smart demolition, followed by new innovative technologies to produce high-grade secondary aggregates with low amount of contaminants. This paper firstly reports the level of co...

  9. Model testing for the remediation assessment of a radium contaminated site in Olen, Belgium

    International Nuclear Information System (INIS)

    Environmental assessment models are used as decision-aiding tools in the selection of remediation options for radioactively contaminated sites. In most cases, the effectiveness of the remedial actions in terms of dose savings cannot be demonstrated directly, but can be established with the help of environmental assessment models, through the assessment of future radiological impacts. It should be emphasized that, given the complexity of the processes involved and our current understanding of how they operate, these models are simplified descriptions of the behaviour of radionuclides in the environment and therefore imperfect. One way of testing and improving the reliability of the models is to compare their predictions with real data and/or the predictions of other models. Within the framework of the Remediation Assessment Working Group (RAWG) of the BIOMASS (BIOsphere Modelling and ASSessment) programme coordinated by IAEA, two scenarios were constructed and applied to test the reliability of environmental assessment models when remedial actions are involved. As a test site, an area of approximately 100 ha contaminated by the discharges of an old radium extraction plant in Olen (Belgium) has been considered. In the first scenario, a real situation was evaluated and model predictions were compared with measured data. In the second scenario the model predictions for specific hypothetical but realistic situations were compared. Most of the biosphere models were not developed to assess the performance of remedial actions and had to be modified for this purpose. It was demonstrated clearly that the modeller's experience and familiarity with the mathematical model, the site and with the scenario play a very important role in the outcome of the model calculations. More model testing studies, preferably for real situations, are needed in order to improve the models and modelling methods and to expand the areas in which the models are applicable

  10. Assessment of PCDD/Fs levels in soil at a contaminated sawmill site in Sweden – A GIS and PCA approach to interpret the contamination pattern and distribution

    International Nuclear Information System (INIS)

    Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans (PCDD/Fs) were analysed in soil from a Swedish sawmill site where chlorophenols (CPs) had been used more than 40 years ago. The most contaminated area at the site was the preservation subarea where the PCDD/F WHO2005-TEQ level was 3450 times higher than the current Swedish guideline value of 200 ng TEQ/kg soil for land for industrial use. It was also shown that a fire which destroyed the sawmill might have affected the congener distribution at the concerned areas. To get a broader picture of the contamination both GIS (spatial interpolation analysis) and multivariate data analysis (PCA) were applied to visualize and compare PCDD/F levels as well as congener distributions at different areas at the site. It is shown that GIS and PCA are powerful tools in decisions on future investigations, risk assessments and remediation of contaminated sites. -- Highlights: •GIS and PCA visualize and compare site levels and congener patterns of dioxins. •Subareas were separated by differences in contamination levels and congener patterns. •Fire had a significant effect on the congener distribution at the site. -- The use of geostatistical and multivariate statistical methods are powerful tools to visualize the contamination pattern and distribution at a highly PCDD/Fs-contaminated site

  11. Risk assessment of cadmium-contaminated soil on plant DNA damage using RAPD and physiological indices

    International Nuclear Information System (INIS)

    Impact assessment of contaminants in soil is an important issue in environmental quality study and remediation of contaminated land. A random amplified polymorphic DNA (RAPD) 'fingerprinting' technique was exhibited to detect genotoxin-induced DNA damage of plants from heavy metal contaminated soil. This study compared the effects occurring at molecular and population levels in barley seedlings exposed to cadmium (Cd) contamination in soil. Results indicate that reduction of root growth and increase of total soluble protein level in the root tips of barley seedlings occurred with the ascending Cd concentrations. For the RAPD analyses, nine 10-base pair (bp) random RAPD primers (decamers) with 60-70% GC content were found to produce unique polymorphic band patterns and subsequently were used to produce a total of 129 RAPD fragments of 144-2639 base pair in molecular size in the root tips of control seedlings. Results produced from nine primers indicate that the changes occurring in RAPD profiles of the root tips following Cd treatment included alterations in band intensity as well as gain or loss of bands compared with the control seedlings. New amplified fragments at molecular size from approximately 154 to 2245 bp appeared almost for 10, 20 and 40 mg L-1 Cd with 9 primers (one-four new polymerase chain reaction, (PCR) products), and the number of missing bands enhanced with the increasing Cd concentration for nine primers. These results suggest that genomic template stability reflecting changes in RAPD profiles were significantly affected and it compared favourably with the traditional indices such as growth and soluble protein level at the above Cd concentrations. The DNA polymorphisms detected by RAPD can be applied as a suitable biomarker assay for detection of the genotoxic effects of Cd stress in soil on plants. As a tool in risk assessment the RAPD assay can be used in characterisation of Cd hazard in soil

  12. Assessment of heavy metal contamination, levels in topsoil at selected auto-workshops in Accra, Ghana

    International Nuclear Information System (INIS)

    The research was conducted to assess the levels of contamination of heavy metals in the topsoil at selected auto-workshops in Accra to determine the anthropogenic and crustal contributions and the human heath risk associated with them. Soil samples collected from four auto-workshops were analysed using Atomic Absorption Spectrometer. Eleven (11) elements: Co, Fe, Cu, Mn, Cr, As, Hg, Zn, Pb, Ni, and Cd were identified in each sample collected from the auto-workshops. Pollution indices; contamintion factor (Cf) index of geoaccumulation (Igeo) and pollution load index (PLI) were used to assess the contamination levels. It revealed the extent of contamination at the auto-workshops for most of the elements which range from low to considerate contamintion. Lead (Pb) recorded the greatest contamination levels at the auto-electrical location. The results from the index of geoccumulation showed no pollution to highly pollution indicting high variations of pollution levels at different locations. The results of the PLI in almost all locations ranged from moderately to extremely polluted. Noncancer effect on children and adults due to exposure to the topsoil were also estimated with some selected metal elements. The hazard quotient (HQ) evaluation, showed ingestion to be the route of exposure to soil dust that results in a higher risk for heavy metals, followed by dermal contact. The effect due to inhalation of resuspended dust particles through the mouth and nose is relatively low. It was observed that, the auto-workshops are generally polluted with heavy metals and therefore posing ill-health effect to the humans and the environment. (au)

  13. Assessing sediment connectivity to understand dynamics of contaminated sediment within coastal catchments of Fukushima Prefecture (Japan)

    Science.gov (United States)

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

    2013-04-01

    The Fukushima Dai-ichi Nuclear Power Plant accident has led to the release of large radionuclide quantities (e.g., about 20 PBq of Cs-137 and 200 PBq of I-131) into the atmosphere. About 80% of the release was blown out and over the Pacific Ocean. The remaining 20% of emissions were deposited as wet and dry deposits on soils of Fukushima Prefecture, mainly between 15-16 March. As most radionuclides are strongly sorbed by fine particles, they are likely to be redistributed within the landscape in association with soil and sediment particles transported by runoff and erosion processes. A spatial analysis of Ag-110m:Cs-137 ratio in soils and river sediments provided a way to trace those transfers. This fingerprinting study showed that particles eroded from inland mountain ranges exposed to the highest initial radionuclide fallout were already dispersed along coastal rivers, most likely during summer typhoons and spring snowmelt. Those results suggest that hillslopes and rivers have become a perennial source of radioactive contaminants to the Pacific Ocean off Fukushima Prefecture. This study aims to specify the location and nature of the preferential sources supplying contaminated material to the main rivers draining the Fukushima contamination plume. To this end, important parameters controlling soil erosion and sediment transfers within catchments, i.e. landscape morphology and land use characteristics, were preliminary derived from DEM data and satellite images for the River Mano, Nitta and Ota catchments (ca. 525 km²) draining the most radioactive part of the contamination plume that formed across Fukushima Prefecture. Then, those data were used to compute indices assessing the potential sediment connectivity (i) between hillslopes and rivers and (ii) between hillslopes and catchment outlets. Finally, spatially-distributed values of connectivity indices were confronted to gamma-emitting radionuclide activities (Cs-134, Cs-137 and Ag-110m) measured in riverbed

  14. Baseline risk assessment of ground water contamination at the inactive uraniferous lignite ashing site near Bowman, North Dakota

    Energy Technology Data Exchange (ETDEWEB)

    1994-11-01

    This baseline risk assessment of ground water contamination at the inactive uraniferous lignite ashing site near Bowman, North Dakota, evaluates the potential impacts to public health or the environment from contaminated ground water at this site. This contamination is a result of the uraniferous lignite ashing process, when coal containing uranium was burned to produce uranium. Potential risk is quantified only for constituents introduced by the processing activities and not for the constituents naturally occurring in background ground water in the site vicinity. Background ground water, separate from any site-related contamination, imposes a percentage of the overall risk from ground water ingestion in the Bowman site vicinity. The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project is developing plans to address soil and ground water contamination at the site. The UMTRA Surface Project involves the determination of the extent of soil contamination and design of an engineered disposal cell for long-term storage of contaminated materials. The UMTRA Ground Water Project evaluates ground water contamination. Based on results from future site monitoring activities as defined in the site observational work plan and results from this risk assessment, the DOE will propose an approach for managing contaminated ground water at the Bowman site.

  15. Baseline risk assessment of ground water contamination at the inactive uraniferous lignite ashing site near Bowman, North Dakota

    International Nuclear Information System (INIS)

    This baseline risk assessment of ground water contamination at the inactive uraniferous lignite ashing site near Bowman, North Dakota, evaluates the potential impacts to public health or the environment from contaminated ground water at this site. This contamination is a result of the uraniferous lignite ashing process, when coal containing uranium was burned to produce uranium. Potential risk is quantified only for constituents introduced by the processing activities and not for the constituents naturally occurring in background ground water in the site vicinity. Background ground water, separate from any site-related contamination, imposes a percentage of the overall risk from ground water ingestion in the Bowman site vicinity. The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project is developing plans to address soil and ground water contamination at the site. The UMTRA Surface Project involves the determination of the extent of soil contamination and design of an engineered disposal cell for long-term storage of contaminated materials. The UMTRA Ground Water Project evaluates ground water contamination. Based on results from future site monitoring activities as defined in the site observational work plan and results from this risk assessment, the DOE will propose an approach for managing contaminated ground water at the Bowman site

  16. Analysis of risk assessment and risk management processes in the derivation of maximum levels for environmental contaminants in food

    OpenAIRE

    Schneider, Klaus; Ollroge, Inga; Clauberg, Martin; Schuhmacher-Wolz, Ulrike

    2007-01-01

    Abstract Environmental contaminants are substances that originate from diffuse sources and may appear in foods based on their ubiquitous presence in the environment. This paper analyses how maximum levels for environmental contaminants in food were derived by the Codex Alimentarius Commission, by the European Union and by national authorities (USA, Germany). Both the risk assessment process (derivation of tolerable intake values and intake assessment by scientific bodies) and the r...

  17. Baseline risk assessment of ground water contamination at the uranium mill tailings site Salt Lake City, Utah

    International Nuclear Information System (INIS)

    This baseline risk assessment of groundwater contamination at the uranium mill tailings site near Salt Lake City, Utah, evaluates potential public health or environmental impacts resulting from ground water contamination at the former uranium ore processing site. The tailings and other contaminated material at this site were placed in a disposal cell located at Clive, Utah, in 1987 by the US Department of Energy's Uranium Mill Tailings Remedial Action (UMTRA) Project. The second phase of the UMTRA Project is to evaluate residual ground water contamination at the former uranium processing site, known as the Vitro processing site. This risk assessment is the first site-specific document under the Ground Water Project. It will help determine the appropriate remedial action for contaminated ground water at the site

  18. Baseline risk assessment of ground water contamination at the uranium mill tailings site Salt Lake City, Utah

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    This baseline risk assessment of groundwater contamination at the uranium mill tailings site near Salt Lake City, Utah, evaluates potential public health or environmental impacts resulting from ground water contamination at the former uranium ore processing site. The tailings and other contaminated material at this site were placed in a disposal cell located at Clive, Utah, in 1987 by the US Department of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Project. The second phase of the UMTRA Project is to evaluate residual ground water contamination at the former uranium processing site, known as the Vitro processing site. This risk assessment is the first site-specific document under the Ground Water Project. It will help determine the appropriate remedial action for contaminated ground water at the site.

  19. In situ radiometric mapping as a proxy of sediment contamination: assessment of the underlying geochemical and -physical principles.

    Science.gov (United States)

    van der Graaf, E R; Koomans, R L; Limburg, J; de Vries, K

    2007-05-01

    Correlations between sediment contaminants like heavy metals or organic micro-compounds and natural or anthropogenic radionuclides ((40)K, (238)U, (232)Th, (137)Cs) facilitates in situ mapping of the contaminated sediment using gamma-ray detectors. These maps can be made quickly and economically using surveys with towed underwater gamma-ray detectors and based on the fundamental correlation of contaminants with radioactivity. This paper aims at an assessment of the geochemical and -physical principles underlying these correlations. This assessment uses multivariate analysis of a data base containing information on radionuclides and contaminants for a large number of sediment samples used to derive radionuclide-contaminant correlations in radiometric mapping projects in freshwater bodies of the Netherlands. More specifically, the aims of this study are to test if these correlations are valid for the entire Dutch freshwater environment and to investigate the validity of the thesis that these correlations are mainly due to the presence of clay. PMID:17258466

  20. Dismantling of the PETRA glove box: tritium contamination and inventory assessment

    International Nuclear Information System (INIS)

    The PETRA facility is the first installation in which experiments with tritium were carried out at the Tritium Laboratory Karlsruhe. After completion of two main experimental programs, the decommissioning of PETRA was initiated with the aim to reuse the glove box and its main still valuable components. A decommissioning plan was engaged to: -) identify the source of tritium release in the glove box, -) clarify the status of the main components, -) assess residual tritium inventories, and -) de-tritiate the components to be disposed of as waste. Several analytical techniques - calorimetry on small solid samples, wipe test followed by liquid scintillation counting for surface contamination assessment, gas chromatography on gaseous samples - were deployed and cross-checked to assess the remaining tritium inventories and initiate the decommissioning process. The methodology and the main outcomes of the numerous different tritium measurements are presented and discussed. (authors)

  1. A study regarding the exposure scenario and key points for the risk assessment of the radioactive cesium contaminated soil

    International Nuclear Information System (INIS)

    The main purpose of this study is to figure out the exposure scenario and clarify the key points for conducting the accurate risk assessment for the soil which is contaminated with a radioactive substance. As a first step, we figured out all conceivable exposure passages which are caused by the radioactive cesium contaminated soil and found that making consideration regarding the kind of exposed subjects, the length of time, the land usage and the distance from the ground zero etc are needed when conducting the accurate risk assessment for the soil which is contaminated with a radioactive substance. (author)

  2. State of the art of contaminated site management in The Netherlands: policy framework and risk assessment tools.

    Science.gov (United States)

    Swartjes, F A; Rutgers, M; Lijzen, J P A; Janssen, P J C M; Otte, P F; Wintersen, A; Brand, E; Posthuma, L

    2012-06-15

    This paper presents the policy framework of contaminated site management in The Netherlands and the corresponding risk assessment tools, including innovations that have taken place since an overview was published in 1999. According to the Dutch Soil Protection Act assessment framework, soils are subdivided into three quality classes: clean, slightly contaminated and seriously contaminated. Historic cases of slightly contaminated soils are managed in a sustainable way by re-use of soil material within a region on the basis of risk-based and land use specific Maximal Values and Background Values. In case of serious soil contamination remediation is in principle necessary and the urgency of remediation has to be determined based on site-specific risks for human health, the ecosystem and groundwater. The major risk assessment tools in The Netherlands are the CSOIL exposure model (human health risks and food safety), Species Sensitivity Distributions and the Soil Quality Triad (ecological risks), along with a procedure to assess the risks due to contaminant spreading to and in the groundwater. Following the principle 'simple if possible, complex when necessary', tiered approaches are used. Contaminated site practices are supported with web-based decision support systems. PMID:22578694

  3. Baseline risk assessment of ground water contamination at the inactive uraniferous lignite ashing site near Belfield, North Dakota. Revision 1

    International Nuclear Information System (INIS)

    This risk assessment evaluates the potential for impacts to public health or the environment from contaminated ground water at this site caused by the burning of coal containing uranium to produce uranium. Potential risk is quantified for constituents introduced from the processing activities and not for those constituents naturally occurring in background ground water in the site vicinity. Because background ground water quality has the potential to cause adverse health effects from exposure through drinking, any risks associated with contaminants attributable to site activities are incremental to these risks from background. The incremental risk from site-related contaminants is quantified in this risk assessment. The baseline risk from background water quality is incorporated only into the assessment of potential chemical interactions and the definition of the overall site condition. The US Department of Energy's (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project is developing plans to remedy soil and ground water contamination at the site. The UMTRA Surface Project consists of determining the extent of soil contamination and disposing of the contaminated soils in an engineered disposal cell. The UMTRA Ground Water Project consists of evaluating ground water contamination. Under the UMTRA Ground Water Project, results of this risk assessment will help determine what ground water compliance strategy may be applied at the site

  4. Radiological risk assessment for an urban area: Focusing on a drinking water contamination

    International Nuclear Information System (INIS)

    This paper specifically discusses a water quality modeling and health risk assessment for cesium-137 to assess the potential and actual effects on human health from drinking water contaminated by a radiological terrorist attack in the Seoul metropolitan area, Korea. With respect to the source term caused by a terrorist attack, it was assumed that 50 TBq of cesium-137 was introduced into the Paldang Lake which is a single water resource for the Seoul metropolitan area. EFDC (Environmental Fluid Dynamics Code) model was used to calculate the hydrodynamic and water quality for the model domain, Paldang Lake. Mortality risk and morbid risk coefficients caused by the ingestion of tap water were used to assess a human health risk due to cesium-137. The transport of cesium-137 in the Paldang water system was mainly dependent on the flow streamlines and the effect of the dilution from the other branches. The mortality and morbidity risks due to the drinking water contamination by cesium-137 were 4.77 x 10-7 and 6.92 x 10-7, respectively. Accordingly, it is very important to take appropriate countermeasures when radiological terrorist attacks have occurred at water resources to prevent radiological risks by radionuclides.

  5. Assessment of regional human health risks from lead contamination in Yunnan province, southwestern China.

    Science.gov (United States)

    Lu, Lu; Cheng, Hongguang; Liu, Xuelian; Xie, Jing; Li, Qian; Zhou, Tan

    2015-01-01

    Identification and management the 'critical risk areas' where hotspot lead exposures are a potential risk to human health, become a major focus of public health efforts in China. But the knowledge of health risk assessment of lead pollution at regional and national scales is still limited in China. In this paper, under the guidance of 'sources-pathways-receptors' framework, regional human health risk assessment model for lead contamination was developed to calculate the population health risk in Yunnan province. And the cluster and AHP (analytic hierarchy process) analysis was taken to classify and calculate regional health risk and the decomposition of the regional health risk in the greatest health risk region, respectively. The results showed that Yunnan province can be divided into three areas. The highest health risk levels, located in northeastern Yunnan, including Kunming, Qujing, Zhaotong region. In those regions, lead is present at high levels in air, food, water and soil, and high population density which pose a high potential population risk to the public. The current study also reveals that most regional health risk was derived from the child receptors (age above 3 years) 4.3 times than the child receptors (age under 3 years), and ingestion of lead-contaminated rice was found to be the most significant contributor to the health risk (accounting for more than 49% health risk of total). This study can provide a framework for regional risk assessment in China and highlighted some indicators and uncertainties. PMID:25893826

  6. Granulometric determinations and inhalation dose assessment for atmospheric aerosol contaminated by 137Cs

    International Nuclear Information System (INIS)

    During the redevelopment of Brescia freight-yard a measurement campaign of atmospheric aerosol was carried out: in fact a 137Cs ground contamination, caused by the permanence of wagons carrying iron materials contaminated by this radionuclide, had been found out. During the redevelopment phases of excavation and can filling the workers were exposed to the danger of radioactive aerosol inhalation. The aim of the measurement campaign was to test the aerosol sampling and granulometric analysis methodologies with their sensitivity related to the inhalation dose assessments. The results of both aerosuspended mass and activity, evaluated by means of a portable cascade impactor, are presented. The granulometries have been interpolated with a log normal distribution using an iterative routine minimizing the square deviation between the calculated and experimental data. The results related to the dose assessments are also presented. These evaluations have been carried out using both the granulometric information obtained and the more recent models (ICRP 66) both the total concentration data and the dose coefficients referring to the standard conditions of ICRP 68 and of the Italian law (D.Lgs. 230/95). Furthermore the significance and the reliability of the dose assessments referring to the different methodologies are discussed, also in relation to the possibility of using this sampling methodologies for other radionuclides and different exposure conditions

  7. Bioeffects Assessment in Kvichak and Nushagak Bay, Alaska: Characterization of Soft Bottom Benthic Habitats, Animal Body Burdens and Contaminant Baseline Assessment

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of this project is to assess habitat conditions that influence biodiversity and distribution of benthic infaunal communities, contaminants, and chemical...

  8. Bioeffects Assessment in Kvichak and Nushagak Bay, Alaska: Characterization of Soft Bottom Benthic Habitats, Fish Body Burdens and Contaminant Baseline Assessment

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of this project is to assess habitat conditions that influence biodiversity and distribution of benthic infaunal communities, contaminants, and chemical...

  9. Long-term safety assessment of live attenuated tetravalent dengue vaccines: deliberations from a WHO technical consultation.

    Science.gov (United States)

    Bentsi-Enchill, Adwoa D; Schmitz, Julia; Edelman, Robert; Durbin, Anna; Roehrig, John T; Smith, Peter G; Hombach, Joachim; Farrar, Jeremy

    2013-05-28

    Dengue is a rapidly growing public health threat with approximately 2.5 billion people estimated to be at risk. Several vaccine candidates are at various stages of pre-clinical and clinical development. Thus far, live dengue vaccine candidates have been administered to several thousands of volunteers and were well-tolerated, with minimal short-term safety effects reported in Phase I and Phase II clinical trials. Based on the natural history of dengue, a theoretical possibility of an increased risk of severe dengue as a consequence of vaccination has been hypothesized but not yet observed. In October 2011, the World Health Organization (WHO) convened a consultation of experts in dengue, vaccine regulation and vaccine safety to review the current scientific evidence regarding safety concerns associated with live attenuated dengue vaccines and, in particular, to consider methodological approaches for their long-term evaluation. In this paper we summarize the scientific background and methodological considerations relevant to the safety assessment of these vaccines. Careful planning and a coordinated approach to safety assessment are recommended to ensure adequate long-term evaluation of dengue vaccines that will support their introduction and continued use. PMID:23570986

  10. Assessment of endocrine-disrupting chemicals attenuation in a coastal plain stream prior to wastewater treatment plant closure

    Science.gov (United States)

    Bradley, Paul M.; Journey, Celeste A.

    2014-01-01

    The U.S. Geological Survey is conducting a combined pre/post-closure assessment at a long-term wastewater treatment plant (WWTP) site at Fort Gordon near Augusta, Georgia. Here, we assess select endocrine-active chemicals and benthic macroinvertebrate community structure prior to closure of the WWTP. Substantial downstream transport and limited instream attenuation of endocrine-disrupting chemicals (EDCs) was observed in Spirit Creek over a 2.2-km stream segment downstream of the WWTP outfall. A modest decline (less than 20% in all cases) in surface water detections was observed with increasing distance downstream of the WWTP and attributed to partitioning to the sediment. Estrogens detected in surface water in this study included estrone (E1), 17β-estradiol (E2), and estriol (E3). The 5 ng/l and higher mean estrogen concentrations observed in downstream locations indicated that the potential for endocrine disruption was substantial. Concentrations of alkylphenol ethoxylate (APE) metabolite EDCs also remained statistically elevated above levels observed at the upstream control site. Wastewater-derived pharmaceutical and APE metabolites were detected in the outflow of Spirit Lake, indicating the potential for EDC transport to aquatic ecosystems downstream of Fort Gordon. The results indicate substantial EDC occurrence, downstream transport, and persistence under continuous supply conditions and provide a baseline for a rare evaluation of ecosystem response to WWTP closure.

  11. Immunochemical assessment of mycotoxins in 1989 grain foods: evidence for deoxynivalenol (vomitoxin) contamination.

    OpenAIRE

    Abouzied, M M; Azcona, J I; W.E. Braselton; Pestka, J J

    1991-01-01

    To assess the potential for mycotoxin contamination of the human food supply following the 1988 U.S. drought, 92 grain food samples were purchased from retail outlets in the summer of 1989 and surveyed for aflatoxin B1, zearalenone, and deoxynivalenol (DON [vomitoxin]) by monoclonal antibody-based competitive enzyme-linked immunosorbent assay (ELISA). Only one sample (buckwheat flour) was found to contain aflatoxin B1 (12 ng/g), whereas zearalenone was found in 26% of the samples at a mean co...

  12. Risk assessment of lead contamination for small mammal food chains (case studyfor shooting ranges)

    OpenAIRE

    Al Sayegh-Petkovšek, Samar; Tome, Davorin; Pokorny, Boštjan

    2010-01-01

    Pb levels were measured in tissues of small mammals (Microtus agrestis, Apodemus flavicollis, Sorex araneus and Crocidura leucodon), inhabiting shooting ranges of the Slovenian Army (Apače, Bač, Bloška polica, Crngrob, Mačkovec, Poček); in addition, Pb content was analysed in their diet as well. The present research was performed with the aim to confirm the use of small mammals as bioindicators of Pb contamination of shooting ranges and to performthe risk assessment of military shooting range...

  13. Assessment of Ecological Risk of Heavy Metal Contamination in Coastal Municipalities of Montenegro

    Directory of Open Access Journals (Sweden)

    Boban Mugoša

    2016-03-01

    Full Text Available Assessment of heavy metal concentrations in the soil samples of urban parks and playgrounds is very important for the evaluation of potential risks for residents, especially children. Until recently, there has been very little data about urban parks pollution in Montenegro. To evaluate the sources of potential contamination and concentration of heavy metals, soil samples from coastal urban parks and kindergartens of Montenegro were collected. Based on the heavy metal concentrations, multivariate analysis combined with geochemical approaches showed that soil samples in coastal areas of Montenegro had mean Pb and Cd concentrations that were over two times higher than the background values, respectively. Based on principal component analysis (PCA, soil pollution with Pb, Cd, Cu, and Zn is contributed by anthropogenic sources. Results for Cr in the surface soils were primarily derived from natural sources. Calculation of different ecological contamination factors showed that Cd is the primary contribution to ecological risk index (RI origins from anthropogenic, industry, and urbanization sources. This data provides evidence about soil pollution in coastal municipalities of Montenegro. Special attention should be paid to this problem in order to continue further research and to consider possible ways of remediation of the sites where contamination has been observed.

  14. Characterization and risk assessment of sites contaminated by natural series radionuclides

    International Nuclear Information System (INIS)

    Radioactive isotopes are widespread in the environment. In addition to the nuclear industry, oil and gas extraction, the mining of ores, ore processing, fertilizer and abrasives production, military activities and power generation from coal, all contribute to the annual radiological dose received by members of the public. However, whereas routine discharges from nuclear licensed sites are carefully monitored, the fate of natural series radionuclides concentrated by industrial processes is less well known. The nature of these activities dictates that radioactive contamination is often dispersed over large areas and accompanied by elevated concentrations of organic contaminants, heavy metals or both. This presents a severe challenge to regulators and those tasked with implementing a remediation strategy for such complex sites. Assessing the risk associated with ingestion or inhalation of radioactive contaminants relies on detailed characterization of the transport medium and potential source sinks for pollutants along the transport pathway. Currently, reliance is placed on empirical sorption or transfer coefficients to account for retardation and uptake, respectively. Models of this type are difficult to justify. They fail to describe the processes occurring and it can be shown that the outcome of such risk calculations is not necessarily conservative. It is essential to differentiate pollutants in terms of their mineralogy, chemistry, morphology, solubility and isotopic composition, as only this provides an adequate basis for future decision making. Procedures used to devise remediation strategies are illustrated by reference to recent case studies. (author)

  15. Assessment and management of contaminated sediments in Italian marine coastal waters

    International Nuclear Information System (INIS)

    The Water Framework Directive (WFD) obliges Member State to achieve a good chemical and ecological status of all surface water bodies within a specific deadline; in particular the good chemical status is a condition in which the concentrations of priority substances do not exceed the environmental quality standards (EQS) in order to protect human health and the environment; the WFD states that EQS have to be derived for water, sediment or biota. The good chemical status could be difficult to achieve in the historical marine contaminated water bodies due to the presence of high concentrations of toxic, bio accumulative and persistent substances in the sediments. In these specific highly contaminated sites there is a need to apply an ecosystem approach in which, as a first step, less stringent sediment EQS are defined in order to take the appropriate measures for the protection of aquatic ecosystems and human health; the long-term goal for these sites is the achievement of the good chemical status foreseen by the WFD. The methodology applied in Italy for the sediment quality assessment of marine contaminated sites is explained in this paper

  16. Contamination and risk assessment of heavy metals in bottom sediments from Lake Valencia, Venezuela

    Directory of Open Access Journals (Sweden)

    González A.

    2013-04-01

    Full Text Available The contamination and risk assessment of heavy metals in the bottom sediments of the Lake Valencia, Venezuela, was performed by determining the Enrichment Factor (EF, the Geoaccumulation Factor (Igeo, the availability of metals and the Risk Index Code (RAC. The sediments were anthropogenic ally enriched with Pb, Zn, Cu and Cr and classified as uncontaminated to moderately contaminated, with a medium risk of Zn, Co, Ni and Cr, and low risk of Cu, Pb and Cd. Analysis of correlations and PCA showed temporal variations in the concentration of metals in the sediments during the rainy season, and spatial variations, where the depth and anthropogenic inputs are the main variables. The contamination of sediments was located on the axis connecting the mouths of the river Guayos, which crosses the city of Valencia, and the river Güey which crosses the city of Maracay, both highly industrialized. Although the concentration of dissolved heavy metals into the waters was within the regulations, important concentrations of Pb and Hg and the bioaccumulation of Hg and Cr, determined by the Bioconcentration Factor (BCF, were found in the fish tissues which indicate that the metal enrichment of the lake sediments is affecting the biota.

  17. Assessment of groundwater contamination from a hazardous dump site in Ranipet, Tamil Nadu, India

    Science.gov (United States)

    Rao, G. Tamma; Rao, V. V. S. Gurunadha; Ranganathan, K.; Surinaidu, L.; Mahesh, J.; Ramesh, G.

    2011-12-01

    Tanneries located in an industrial development area of Ranipet (India) manufactured chromate chemicals during 1976-1996. A large quantity of associated hazardous solid wastes has been stacked about 5-m high above ground level, spread over 3.5 ha inside one of the factory premises. The study area receives an average annual rainfall of 1,100 mm. The granitic formation in the northern part of Palar River catchment has high infiltration rates and has resulted in fast migration of the contamination to the water table. Chromium levels in the groundwater were found up to 275 mg/l. The available hydrogeological, geophysical and groundwater quality data bases have been used to construct a groundwater flow and mass transport model for assessing the groundwater contamination and it has been calibrated for the next 30 years. The migration has been found to be very slow, with a groundwater velocity of 10 m/year. This is the first field-scale study of its kind in this industrial area. The findings are of relevance to addressing the groundwater pollution due to indiscriminate disposal practices of hazardous waste in areas located on the phreatic aquifer. Further, it has been reported that the untreated effluent discharge adjacent to the chromium dump site is most influential in the migration of contaminants.

  18. Assessing the State of Contamination in a Historic Mining Town Using Sediment Chemistry.

    Science.gov (United States)

    Gutiérrez, Mélida; Wu, Shuo-Sheng; Rodriguez, Jameelah R; Jones, Ashton D; Lockwood, Benjamin E

    2016-05-01

    The United States town of Aurora, Missouri, USA, stockpiled lead (Pb) and zinc (Zn) mining wastes from the early to mid-1900s in the form of chat piles. Clean-up actions were undertaken at intervals in subsequent years including land leveling and removal of chat. This study assessed the current state of contamination by identifying areas where metals are present at toxic levels. For this purpose, stream sediment samples (N = 100) were collected over a 9 × 12 km area in and around Aurora. Their content of cadmium (Cd), Pb, and Zn were measured, and concentration maps were generated using ArcGIS to categorize affected areas. Metal concentrations varied over a wide range of values with the overall highest values observed in the north-northeast part of Aurora where abundant chat piles had been present. Comparison between observed concentrations and sediment-quality guidelines put the contaminated areas mentioned are above-toxic levels for Cd, Pb and Zn. In contrast, levels in rural areas and the southern part of Aurora were at background levels, thus posing no threat to aquatic habitats. The fact that contamination is constrained to a relatively small area can be advantageously used to implement further remediation and, by doing so, to help protect the underlying karst aquifer. PMID:26847833

  19. Assessing risk to human health from tropical leafy vegetables grown on contaminated urban soils

    Energy Technology Data Exchange (ETDEWEB)

    Nabulo, G.; Young, S.D.; Black, C.R., E-mail: colin.black@nottingham.ac.uk [School of Biosciences, University of Nottingham, Nottingham, NG7 2RD (United Kingdom)

    2010-10-15

    Fifteen tropical leafy vegetable types were sampled from farmers' gardens situated on nine contaminated sites used to grow vegetables for commercial or subsistence consumption in and around Kampala City, Uganda. Trace metal concentrations in soils were highly variable and originated from irrigation with wastewater, effluent discharge from industry and dumping of solid waste. Metal concentrations in the edible shoots of vegetables also differed greatly between, and within, sites. Gynandropsis gynandra consistently accumulated the highest Cd, Pb and Cu concentrations, while Amaranthus dubius accumulated the highest Zn concentration. Cadmium uptake from soils with contrasting sources and severity of contamination was consistently lowest in Cucurbita maxima and Vigna unguiculata, suggesting these species were most able to restrict Cd uptake from contaminated soil. Concentrations of Pb and Cr were consistently greater in unwashed, than in washed, vegetables, in marked contrast to Cd, Ni and Zn. The risk to human health, expressed as a 'hazard quotient' (HQ{sub M}), was generally greatest for Cd, followed successively by Pb, Zn, Ni and Cu. Nevertheless, it was apparent that urban cultivation of leafy vegetables could be safely pursued on most sites, subject to site-specific assessment of soil metal burden, judicious choice of vegetable types and adoption of washing in clean water prior to cooking.

  20. Assessing risk to human health from tropical leafy vegetables grown on contaminated urban soils

    International Nuclear Information System (INIS)

    Fifteen tropical leafy vegetable types were sampled from farmers' gardens situated on nine contaminated sites used to grow vegetables for commercial or subsistence consumption in and around Kampala City, Uganda. Trace metal concentrations in soils were highly variable and originated from irrigation with wastewater, effluent discharge from industry and dumping of solid waste. Metal concentrations in the edible shoots of vegetables also differed greatly between, and within, sites. Gynandropsis gynandra consistently accumulated the highest Cd, Pb and Cu concentrations, while Amaranthus dubius accumulated the highest Zn concentration. Cadmium uptake from soils with contrasting sources and severity of contamination was consistently lowest in Cucurbita maxima and Vigna unguiculata, suggesting these species were most able to restrict Cd uptake from contaminated soil. Concentrations of Pb and Cr were consistently greater in unwashed, than in washed, vegetables, in marked contrast to Cd, Ni and Zn. The risk to human health, expressed as a 'hazard quotient' (HQM), was generally greatest for Cd, followed successively by Pb, Zn, Ni and Cu. Nevertheless, it was apparent that urban cultivation of leafy vegetables could be safely pursued on most sites, subject to site-specific assessment of soil metal burden, judicious choice of vegetable types and adoption of washing in clean water prior to cooking.

  1. Assessment of Ecological Risk of Heavy Metal Contamination in Coastal Municipalities of Montenegro

    Science.gov (United States)

    Mugoša, Boban; Đurović, Dijana; Nedović-Vuković, Mirjana; Barjaktarović-Labović, Snežana; Vrvić, Miroslav

    2016-01-01

    Assessment of heavy metal concentrations in the soil samples of urban parks and playgrounds is very important for the evaluation of potential risks for residents, especially children. Until recently, there has been very little data about urban parks pollution in Montenegro. To evaluate the sources of potential contamination and concentration of heavy metals, soil samples from coastal urban parks and kindergartens of Montenegro were collected. Based on the heavy metal concentrations, multivariate analysis combined with geochemical approaches showed that soil samples in coastal areas of Montenegro had mean Pb and Cd concentrations that were over two times higher than the background values, respectively. Based on principal component analysis (PCA), soil pollution with Pb, Cd, Cu, and Zn is contributed by anthropogenic sources. Results for Cr in the surface soils were primarily derived from natural sources. Calculation of different ecological contamination factors showed that Cd is the primary contribution to ecological risk index (RI) origins from anthropogenic, industry, and urbanization sources. This data provides evidence about soil pollution in coastal municipalities of Montenegro. Special attention should be paid to this problem in order to continue further research and to consider possible ways of remediation of the sites where contamination has been observed. PMID:27043601

  2. Assessment of photoinduced toxicity of crude oil-contaminated sediments on aquatic invertebrates

    International Nuclear Information System (INIS)

    Accidental crude oil releases resulting in environmental contamination are becoming increasingly widespread and frequent occurrences. Investigations of impacts to aquatic ecosystems following crude oil spills have often uncovered alterations in invertebrate community diversity and species abundance. Crude oil is partially composed of aromatic hydrocarbons, including some phototoxic polycyclic aromatic hydrocarbons (PAHs). To assess organism phototoxic response to PAHs present in crude oil, laboratory toxicity tests were conducted with porewater extracts from crude oil-contaminated sediments and reference sediments using Ceriodaphnia dubia and Hyalella azteca. Test organisms were exposed to porewater samples under artificial near-ultraviolet (UV) radiation and normal laboratory white fluorescent lighting. Controls under both lighting exposures included: culture water controls, anthracene controls (representing a known phototoxic PAH), and solvent controls. Following acute exposure periods, C. dubia mortality under near-UV light in crude oil porewater was significantly different from corresponding mortality under fluorescent light. C. dubia experienced 100% mortality in crude oil sediment porewater under near-UV light, 0% mortality in reference sediment porewater under near-UV light, and 0% mortality across corresponding treatments under fluorescent light exposures. H. azteca mortality under near-UV light in crude oil porewater was also significantly different from corresponding treatments under fluorescent light. Laboratory results suggest that PAHs in crude oil-contaminated sediments in the aquatic environment have the potential to substantially adversely affect survival of UV-exposed aquatic invertebrates

  3. Demilitarization of conventional ordnance: Priorities for data-base assessments of environmental contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Layton, D.W.; McKone, T.E.; Hall, C.H.; Nelson, M.A.; Ricker, Y.E.

    1986-02-01

    The primary goal of this study has been to identify a set of environmental by-products from the demilitarization of conventional ordnance that should be the subject of more detailed data-base assessments. In order to rank the by-products according to their potential health risks, estimates were made of the contaminant releases associated with destructive techniques (e.g., open burning, open detonation, and incineration) and nondestructive techniques (e.g., filler recovery and reuse). Estimates of the types and quantities of propellants, explosives, and pyrotechnics in the demilitarization inventories of various installations in the US were made. To calculate hypothetical doses to man from contaminant releases, a multimedia compartmental model was used to calculate the concentrations of contaminants in water, soils, air, and biota. Based on an analysis of the doses and toxicity data for the compounds, several substances were recommended for further analysis, including DNT, TNT, and RDX and their degradation products in the environment. Other compounds are dibutyl phthalate, diphenylamine, HMX, and tetryl.

  4. Incorporating biomarkers in ecological risk assessment of chemical contaminants of soils

    Directory of Open Access Journals (Sweden)

    A. J. Reinecke

    2007-09-01

    Full Text Available Soil is an important but complex natural resource which is increasingly used as sink for chemicals. The monitoring of soil quality and the assessment of risks posed by contaminants have become crucial. This study deals with the potential use of biomarkers in the monitoring of soils and the assessment of risk resulting from contamination. Apart from an overview of the existing literature on biomarkers, the results of various of our field experiments in South African soils are discussed. Biomarkers may have potential in the assessment of risk because they can indicate at an early stage that exposure has taken place and that a toxic response has been initiated. It is therefore expected that early biomarkers will play an increasing role as diagnostic tools for determining exposure to chemicals and the resulting effects. They may have predictive value that can assist in the prevention or minimising of risks. The aim of this study was to investigate the possibilities of using our results on biomarker responses of soil dwelling organisms to predict changes at higher organisational levels (which may have ecological implications. Our recent experimental results on the evaluation of various biomarkers in both the laboratory and the field are interpreted and placed in perspective within the broader framework of response biology. The aim was further to contribute to the development and application of biomarkers in regulatory risk assessment schemes of soils. This critical review of our own and recent literature on biomarkers in ecotoxicology leads to the conclusion that biomarkers can, under certain conditions, be useful tools in risk assessment. Clear relationships between contamination loads in soil organisms and certain biomarker responses were determined in woodlice, earthworms and terrestrial snails. Clear correlations were also established in field experiments between biomarker responses and changes at the population level. This indicated that, in

  5. Preliminary risk assessment of Power Plant Plomin site contaminated by radioactive slag and ash

    International Nuclear Information System (INIS)

    There is a certain number of radioactively contaminated sites in the Republic of Croatia, one of them being known as Power Plant Plomin site, which contains radioactive slag and ash. Due to a relatively high quantity of the deposited material, as well as relatively high population density of the neighbouring area, it is very important to assess the impact of the site on human health and environment. Using RESRAD computer code and PATHRAE method a preliminary assessment of doses and radiation risks for the workers who spend most of their working day at the pile has been performed. PATHRAE method has also been used for the assessment of radiation risks for the neighbouring population. The assessment is preliminary in its character due to the lack of input data. On the basis of assessment results, recommendations are being given comprising measurements to be taken with a view to coming up with the final risk assessment, as well as protective measures which should be undertaken in the meantime. (author)

  6. ENHANCEMENTS TO NATURAL ATTENUATION: SELECTED CASE STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K; W. H. Albright, W; E. S. Becvar, E; C. H. Benson, C; T. O. Early, T; E. Hood, E; P. M. Jardine, P; M. Lorah, M; E. Majche, E; D. Major, D; W. J. Waugh, W; G. Wein, G; O. R. West, O

    2007-05-15

    In 2003 the US Department of Energy (DOE) embarked on a project to explore an innovative approach to remediation of subsurface contaminant plumes that focused on introducing mechanisms for augmenting natural attenuation to achieve site closure. Termed enhanced attenuation (EA), this approach has drawn its inspiration from the concept of monitored natural attenuation (MNA).

  7. Baseline risk assessment for exposure to contaminants at the St. Louis Site, St. Louis, Missouri

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    The St. Louis Site comprises three noncontiguous areas in and near St. Louis, Missouri: the St. Louis Downtown Site (SLDS), the St. Louis Airport Storage Site (SLAPS), and the Latty Avenue Properties. The main site of the Latty Avenue Properties includes the Hazelwood Interim Storage Site (HISS) and the Futura Coatings property, which are located at 9200 Latty Avenue. Contamination at the St. Louis Site is the result of uranium processing and disposal activities that took place from the 1940s through the 1970s. Uranium processing took place at the SLDS from 1942 through 1957. From the 1940s through the 1960s, SLAPS was used as a storage area for residues from the manufacturing operations at SLDS. The materials stored at SLAPS were bought by Continental Mining and Milling Company of Chicago, Illinois, in 1966, and moved to the HISS/Futura Coatings property at 9200 Latty Avenue. Vicinity properties became contaminated as a result of transport and movement of the contaminated material among SLDS, SLAPS, and the 9200 Latty Avenue property. This contamination led to the SLAPS, HISS, and Futura Coatings properties being placed on the National Priorities List (NPL) of the US Environmental Protection Agency (EPA). The US Department of Energy (DOE) is responsible for cleanup activities at the St. Louis Site under its Formerly Utilized Sites Remedial Action Program (FUSRAP). The primary goal of FUSRAP is the elimination of potential hazards to human health and the environment at former Manhattan Engineer District/Atomic Energy Commission (MED/AEC) sites so that, to the extent possible, these properties can be released for use without restrictions. To determine and establish cleanup goals for the St. Louis Site, DOE is currently preparing a remedial investigation/feasibility study-environmental impact statement (RI/FS-EIS). This baseline risk assessment (BRA) is a component of the process; it addresses potential risk to human health and the environment associated wi

  8. Baseline risk assessment for exposure to contaminants at the St. Louis Site, St. Louis, Missouri

    International Nuclear Information System (INIS)

    The St. Louis Site comprises three noncontiguous areas in and near St. Louis, Missouri: the St. Louis Downtown Site (SLDS), the St. Louis Airport Storage Site (SLAPS), and the Latty Avenue Properties. The main site of the Latty Avenue Properties includes the Hazelwood Interim Storage Site (HISS) and the Futura Coatings property, which are located at 9200 Latty Avenue. Contamination at the St. Louis Site is the result of uranium processing and disposal activities that took place from the 1940s through the 1970s. Uranium processing took place at the SLDS from 1942 through 1957. From the 1940s through the 1960s, SLAPS was used as a storage area for residues from the manufacturing operations at SLDS. The materials stored at SLAPS were bought by Continental Mining and Milling Company of Chicago, Illinois, in 1966, and moved to the HISS/Futura Coatings property at 9200 Latty Avenue. Vicinity properties became contaminated as a result of transport and movement of the contaminated material among SLDS, SLAPS, and the 9200 Latty Avenue property. This contamination led to the SLAPS, HISS, and Futura Coatings properties being placed on the National Priorities List (NPL) of the US Environmental Protection Agency (EPA). The US Department of Energy (DOE) is responsible for cleanup activities at the St. Louis Site under its Formerly Utilized Sites Remedial Action Program (FUSRAP). The primary goal of FUSRAP is the elimination of potential hazards to human health and the environment at former Manhattan Engineer District/Atomic Energy Commission (MED/AEC) sites so that, to the extent possible, these properties can be released for use without restrictions. To determine and establish cleanup goals for the St. Louis Site, DOE is currently preparing a remedial investigation/feasibility study-environmental impact statement (RI/FS-EIS). This baseline risk assessment (BRA) is a component of the process; it addresses potential risk to human health and the environment associated wi

  9. Assessment of contamination in water and soil surrounding a chlor-alkali plant: a case study

    International Nuclear Information System (INIS)

    As a consequence of increasing industrialization without environmental governance, Pakistan is seriously confronted by many complex and difficult environmental challenges related to water and soil pollution. Among these pollution types, pollution due to heavy metals is of serious concern due to their harmful effects on living organisms. In Pakistan, a mercury-cell chlor-alkali plant (MCCAP), installed at Kala Shah Kaku industrial zone, is causing serious environmental degradation in nearby areas due to the direct discharge of its wastewater in the fresh water of Nullah Daik. The production capacity of the MCCAP is, approximately, 33 thousand metric tons per year. Furthermore, due to monsoon flomercuryoding every year, agricultural fields around the Nullah Daik are also suspected to significant contamination. Theefore, assessment of contamination in the waters of Nullah Daik as well as nearby agriculture fields is an important task to study. This study was conducted to analyse the mercury level in both water and soil samples surrounding MCCAP using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Results confirm the presence of heterogeneous Hg contamination with concentrations ranging between 0.1 to 6.71 mu g L-1 in the water samples. Furthermore, significant Hg concentration, ranging between 0.1 - 14.8 mg kg-1, was also observed in the soil samples collected along the banks of Nullah Daik. However, water and soil samples collected from the upstream, from point of convergence of the MCCAP wastewater to the Nullah, do not show any Hg contamination. Hence, the study suggests the development of specific legislative instruments in Pakistan concerning with the surface and soil water pollution and application of treatment strategies in highly polluted areas in order to avoid potential health concern on communities dwelling banks of Nullah Daik and River Ravi. (author)

  10. Assessment of the mobility and bioavailability of 60 Co and 137 Cs in contaminated soils

    International Nuclear Information System (INIS)

    Results of a classical sequential chemical extraction procedure for 137 Cs in an acid Oxisol showed that after 3 years of contamination radiocesium remains potentially available for transfer processes: 40% bio-available, 20% mobile under oxidizing conditions and 40% bound to Fe and Mn oxides (available under reducing conditions). At this time, the transfer factor obtained in this soil was higher than values obtained in basic Oxisol and was higher than values obtained in soils from temperate climate areas. Seven years after the contamination, the 137 Cs distribution in this acid Oxisol have been changed as consequence of changes in soil properties: 8% bioavailable, 16% mobile under oxidizing conditions, 43% bound to Fe and Mn oxides and 33% strongly bound to soil compounds. Changes in the 137 Cs distribution in this soil were followed by reductions in soil to plant transfer factor. Between 1996 and 2000, the 137 Cs distribution, 137 Cs soil to plant transfer factor and soil properties in the basic Oxisol remained almost the same. The 60 Co distribution showed that Mn oxides is the main sink for this element and four years after contamination no 60 Co was detected as bioavailable or detectable in plants. In this study the use of an alternative sequential chemical extraction protocol to evaluate 60 Co and 137 Cs mobility under a large range of physico-chemical soil properties has shown to be very consistent with soil to plant transfer factors data for maize. The knowledge of bio-geochemical behavior of radionuclides in soil system can be used for the risk assessment in the case of nuclear accident or contamination scenarios. (author)

  11. Baseline risk assessment of ground water contamination at the uranium mill tailings site near Lakeview, Oregon. Revision 1

    International Nuclear Information System (INIS)

    Surface cleanup at the Uranium Mill Tailings Remedial Action (UMTRA) Project site near Lakeview, Oregon was completed in 1989. The Ground Water Project evaluates the nature and extent of ground water contamination that resulted from the uranium ore processing activities. The Ground Water Project is in its beginning stages. Human health may be at risk from exposure to ground water contaminated by uranium ore processing. Exposure could occur by drinking water pumped out of a hypothetical well drilled in the contaminated areas. Ecological risks to plants or animals may result from exposure to surface water and sediment that have received contaminated ground water. A risk assessment describes a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the ecological environment may be exposed, and the health or ecological effects that could result from that exposure. This risk assessment is a site-specific document that will be used to evaluate current and potential future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will determine whether any action is needed to protect human health or the ecological environment

  12. Baseline risk assessment of ground water contamination at the uranium mill tailings site near Lakeview, Oregon. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    Surface cleanup at the Uranium Mill Tailings Remedial Action (UMTRA) Project site near Lakeview, Oregon was completed in 1989. The Ground Water Project evaluates the nature and extent of ground water contamination that resulted from the uranium ore processing activities. The Ground Water Project is in its beginning stages. Human health may be at risk from exposure to ground water contaminated by uranium ore processing. Exposure could occur by drinking water pumped out of a hypothetical well drilled in the contaminated areas. Ecological risks to plants or animals may result from exposure to surface water and sediment that have received contaminated ground water. A risk assessment describes a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the ecological environment may be exposed, and the health or ecological effects that could result from that exposure. This risk assessment is a site-specific document that will be used to evaluate current and potential future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will determine whether any action is needed to protect human health or the ecological environment.

  13. Baseline risk assessment of ground water contamination at the Monument Valley uranium mill tailings site Cane Valley, Arizona

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (Phase I) and the Ground Water Project (Phase II). Under the UMTRA Surface Project, tailings, radioactive contaminated soil, equipment, and materials associated with the former uranium ore processing at UMTRA Project sites are placed into disposal cells. The cells are designed to reduce radon and other radiation emissions and to minimize further contamination of ground water. Surface cleanup at the Monument Valley UMTRA Project site near Cane Valley, Arizona, was completed in 1994. The Ground Water Project evaluates the nature and extent of ground water contamination that resulted from the uranium ore processing activities. The Ground Water Project is in its beginning stages. Human health may be at risk from exposure to ground water contaminated by uranium ore processing. Exposure could occur by drinking water pumped out of a hypothetical well drilled in the contaminated areas. Adverse ecological and agricultural effects may also result from exposure to contaminated ground water. For example, livestock should not be watered with contaminated ground water. A risk assessment describes a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the ecological environment may be exposed, and the health or ecological effects that could result from that exposure. This risk assessment is a site-specific document that will be used to evaluate current and potential future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site investigations will be used to determine a compliance strategy to comply with the UMTRA ground water standards

  14. Baseline risk assessment of ground water contamination at the Monument Valley uranium mill tailings site Cane Valley, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    The U.S. Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (Phase I) and the Ground Water Project (Phase II). Under the UMTRA Surface Project, tailings, radioactive contaminated soil, equipment, and materials associated with the former uranium ore processing at UMTRA Project sites are placed into disposal cells. The cells are designed to reduce radon and other radiation emissions and to minimize further contamination of ground water. Surface cleanup at the Monument Valley UMTRA Project site near Cane Valley, Arizona, was completed in 1994. The Ground Water Project evaluates the nature and extent of ground water contamination that resulted from the uranium ore processing activities. The Ground Water Project is in its beginning stages. Human health may be at risk from exposure to ground water contaminated by uranium ore processing. Exposure could occur by drinking water pumped out of a hypothetical well drilled in the contaminated areas. Adverse ecological and agricultural effects may also result from exposure to contaminated ground water. For example, livestock should not be watered with contaminated ground water. A risk assessment describes a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the ecological environment may be exposed, and the health or ecological effects that could result from that exposure. This risk assessment is a site-specific document that will be used to evaluate current and potential future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site investigations will be used to determine a compliance strategy to comply with the UMTRA ground water standards.

  15. Assessment of the contaminants level in recycled aggregates and alternative new technologies for contaminants recognition and removal

    NARCIS (Netherlands)

    Lotfi, S.; Di Maio, F.; Xia, H.; Serranti, S.; Palmieri, R.; Bonifazi, G.

    2015-01-01

    One of the main challenging problems associated with the use of Recycled Aggregates (RA) is the level of mixed contaminants. For utilizing RA in high-grade applications, it is essential to monitor and minimise the content of the pollutants. To this extent the C2CA concrete recycling process investig

  16. Multi-criteria decision analysis with probabilistic risk assessment for the management of contaminated ground water

    International Nuclear Information System (INIS)

    Traditionally, environmental decision analysis in subsurface contamination scenarios is performed using cost-benefit analysis. In this paper, we discuss some of the limitations associated with cost-benefit analysis, especially its definition of risk, its definition of cost of risk, and its poor ability to communicate risk-related information. This paper presents an integrated approach for management of contaminated ground water resources using health risk assessment and economic analysis through a multi-criteria decision analysis framework. The methodology introduces several important concepts and definitions in decision analysis related to subsurface contamination. These are the trade-off between population risk and individual risk, the trade-off between the residual risk and the cost of risk reduction, and cost-effectiveness as a justification for remediation. The proposed decision analysis framework integrates probabilistic health risk assessment into a comprehensive, yet simple, cost-based multi-criteria decision analysis framework. The methodology focuses on developing decision criteria that provide insight into the common questions of the decision-maker that involve a number of remedial alternatives. The paper then explores three potential approaches for alternative ranking, a structured explicit decision analysis, a heuristic approach of importance of the order of criteria, and a fuzzy logic approach based on fuzzy dominance and similarity analysis. Using formal alternative ranking procedures, the methodology seeks to present a structured decision analysis framework that can be applied consistently across many different and complex remediation settings. A simple numerical example is presented to demonstrate the proposed methodology. The results showed the importance of using an integrated approach for decision-making considering both costs and risks. Future work should focus on the application of the methodology to a variety of complex field conditions to

  17. A tiered approach for probabilistic ecological risk assessment of contaminated sites

    International Nuclear Information System (INIS)

    This paper presents a tiered methodology for probabilistic ecological risk assessment. The proposed approach starts from deterministic comparison (ratio) of single exposure concentration and threshold or safe level calculated from a dose-response relationship, goes through comparison of probabilistic distributions that describe exposure values and toxicological responses of organisms to the chemical of concern, and finally determines the so called distribution-based quotients (DBQs). In order to illustrate the proposed approach, soil concentrations of 1,2,4-trichlorobenzene (1,2,4- TCB) measured in an industrial contaminated site were used for site-specific probabilistic ecological risks assessment. By using probabilistic distributions, the risk, which exceeds a level of concern for soil organisms with the deterministic approach, is associated to the presence of hot spots reaching concentrations able to affect acutely more than 50% of the soil species, while the large majority of the area presents 1,2,4- TCB concentrations below those reported as toxic

  18. Preliminary assessment of contaminants in the sediment and organisms of the Swartkops Estuary, South Africa.

    Science.gov (United States)

    Nel, L; Strydom, N A; Bouwman, H

    2015-12-30

    Urban estuaries are susceptible to metal and organic pollution, yet most remain understudied in South Africa with respect to the presence, concentrations and distribution of contaminants. Metal and organic chemical concentrations were assessed in sediment and organisms from different trophic levels in the lower reaches of the Swartkops Estuary. Species sampled included Upogebia africana (Malacostraca: Upogebiidae), Gilchristella aestuaria (Clupeidae), Psammogobius knysnaensis (Gobiidae), Mugil cephalus (Mugilidae), Lichia amia (Carangidae), Argyrosomus japonicus (Sciaenidae), Pomadasys commersonnii (Haemulidae) and Larus dominicanus (Avis: Laridae). This study is one of the most comprehensive studies to date assessing pollution levels in a food web in estuaries in South Africa. Due to biomagnification, higher concentrations of Arsenic, Lead, Mercury and Cadmium were found in the juveniles stages of popular angling fishes. High concentrations of Cadmium and Arsenic were recorded in the liver of L. amia, A. japonicus and P. commersonnii which exceed international quality food guidelines. Eggs from the gull, L. dominicanus, showed detectable concentrations of PCBs. PMID:26593278

  19. EVALUATION OF DEMONSTRATED AND EMERGING TECHNOLOGIES FOR THE TREATMENT OF CONTAMINATED LAND AND GROUNDWATER (PHASE III) - 1999 SPECIAL SESSION ON MONITORED NATURAL ATTENUATION

    Science.gov (United States)

    This report includes the papers presented at the NATO/CCMS Pilot Study Meeting in Angers, France, May 9-14, 1999, for the special session on Monitored Natural Attenuation (MNA). This is the Phase III of the Evaluation of Demonstrated and Emerging Technologies for the Treatment a...

  20. Assessing ongoing sources of dissolved-phase polychlorinated biphenyls in a contaminated stream.

    Science.gov (United States)

    Dang, Viet D; Walters, David M; Lee, Cindy M

    2013-03-01

    Few studies assess the potential of ongoing sources of "fresh" polychlorinated biphenyls (PCBs) to aquatic systems when direct discharge to the environment has been eliminated. In the present study, the authors used single-layered, low-density polyethylene samplers (PEs) to measure total PCB concentrations, congener profiles, and enantiomeric fractions (EFs) in a contaminated stream and to provide multiple lines of evidence for assessing ongoing inputs of PCB. Concentrations were well above background levels that have been monitored for years. Concentrations significantly increased with distance, the farthest downstream PE concentrations being almost five times greater than those at 79 m downstream of a historical point source. The PCBs in the PEs at 79 m downstream of the contamination source were dominated by low K(OW) congeners, similar to those in the mixture of Aroclors 1016 and 1254 (4:1 v/v) historically released from the former capacitor manufacturer. The only two chiral congeners detected in the PEs downstream were PCBs 91 and 95. The EF values were nonracemic for PCB 91, while the values were either racemic or near racemic for PCB 95. Increased PCB concentrations with distance and a congener composition of predominantly low-weight congeners in the PEs at 79 m downstream of the plant site suggested an ongoing PCB source from the plant site. Chiral signatures suggested aerobic biotransformation of dissolved PCBs but did not shed any light on possible ongoing PCB inputs. PMID:23258773

  1. Assessing ongoing sources of dissolved-phase polychlorinated biphenyls in a contaminated stream

    Science.gov (United States)

    Dang, Viet D.; Walters, David M.; Lee, Cindy M.

    2013-01-01

    Few studies assess the potential of ongoing sources of “fresh” polychlorinated biphenyls (PCBs) to aquatic systems when direct discharge to the environment has been eliminated. In the present study, the authors used single-layered, low-density polyethylene samplers (PEs) to measure total PCB concentrations, congener profiles, and enantiomeric fractions (EFs) in a contaminated stream and to provide multiple lines of evidence for assessing ongoing inputs of PCB. Concentrations were well above background levels that have been monitored for years. Concentrations significantly increased with distance, the farthest downstream PE concentrations being almost five times greater than those at 79 m downstream of a historical point source. The PCBs in the PEs at 79 m downstream of the contamination source were dominated by low KOW congeners, similar to those in the mixture of Aroclors 1016 and 1254 (4:1 v/v) historically released from the former capacitor manufacturer. The only two chiral congeners detected in the PEs downstream were PCBs 91 and 95. The EF values were nonracemic for PCB 91, while the values were either racemic or near racemic for PCB 95. Increased PCB concentrations with distance and a congener composition of predominantly low-weight congeners in the PEs at 79 m downstream of the plant site suggested an ongoing PCB source from the plant site. Chiral signatures suggested aerobic biotransformation of dissolved PCBs but did not shed any light on possible ongoing PCB inputs.

  2. Applying the risk-based corrective action process to ecological assessment of contaminated sites

    International Nuclear Information System (INIS)

    Risk-Based Corrective Action (RBCA) is a process in which site investigation and corrective action are focused on the goals of minimizing human health and environmental risk. A basic framework for the RBCA process is outlined in the American Society for Testing and Materials (ASTM) Emergency Standard Guide ES 38-94, Risk-Based Corrective Action Applied at Petroleum Release Sites . This presentation will include discussion of the critical features and, framework of the RBCA process, and will introduce a propose or RBCA which is specifically tailored to the problem of evaluating and responding to environmental risks. The RBCA process includes a number of useful features which expedite and streamline the site assessment and corrective action selection process. Of particular interest, with respect to environmental risk, is a tiered approach to site investigation. This new proposal includes a tiered methodology for investigating environmental risk which begins with a simple, generic analysis and progresses to a more detailed, site-specific analysis, if warranted. The discussion will also cover an example RBCA assessment of a site contaminated with weathered crude oil, and will include results from a laboratory investigation of the ecological toxicity of the contaminated site soils

  3. Accumulation of Heavy Metals in Vegetable Species Planted in Contaminated Soils and the Health Risk Assessment

    Science.gov (United States)

    Zhou, Hang; Yang, Wen-Tao; Zhou, Xin; Liu, Li; Gu, Jiao-Feng; Wang, Wen-Lei; Zou, Jia-Ling; Tian, Tao; Peng, Pei-Qin; Liao, Bo-Han

    2016-01-01

    The objectives of the present study were to investigate heavy metal accumulation in 22 vegetable species and to assess the human health risks of vegetable consumption. Six vegetable types were cultivated on farmland contaminated with heavy metals (Pb, Cd, Cu, Zn, and As). The target hazard quotient (THQ) method was used to assess the human health risks posed by heavy metals through vegetable consumption. Clear differences were found in the concentrations of heavy metals in edible parts of the different vegetables. The concentrations of heavy metals decreased in the sequence as leafy vegetables > stalk vegetables/root vegetables/solanaceous vegetables > legume vegetables/melon vegetables. The ability of leafy vegetables to uptake and accumulate heavy metals was the highest, and that of melon vegetables was the lowest. This indicated that the low accumulators (melon vegetables) were suitable for being planted on contaminated soil, while the high accumulators (leafy vegetables) were unsuitable. In Shizhuyuan area, China, the total THQ values of adults and children through consumption of vegetables were 4.12 and 5.41, respectively, suggesting that the residents may be facing health risks due to vegetable consumption, and that children were vulnerable to the adverse effects of heavy metal ingestion. PMID:26959043

  4. Toxicity assessing for chlorpyrifos-contaminated soil with three different earthworm test methods

    Institute of Scientific and Technical Information of China (English)

    ZHOU Shi-ping; DUAN Chang-qun; FU Hui; CHEN Yu-hui; WANG Xue-hua; YU Ze-fen

    2007-01-01

    Earthworm toxicity tests are useful tools for terrestrial risk assessment but require a hierarchy of test designs that differ in effect levels (behavior, sublethal, lethal). In this study, the toxicity of chlorpyrifos contaminated soil on earthworms was assessed. In addition to the acute and chronic tests, an avoidance response test was applied. Earthworms were exposed to sublethal and lethal concentration of chlorpyrifos, and evaluated for acute toxicity, growth, fecundity and avoidance response after a certain exposure period. The test methods covered all important ecological relevant endpoints (acute, chronic, behavioral). Concentration of 78.91 mg/kg, chlorpyrifos caused significant toxic effects in all test methods, but at lower test concentrations, only significant chronic toxic effects could be observed. In the present study, chlorpyrifos had adverse effect on growth and fecundity in earthworm exposed to 5 mg/kg chlorpyrifos after eight weeks. The avoidance response test, however, showed significant repellent effects concentration of 40 mg/kg chlorpyrifos. For chlorpyrifos, concentration affecting avoidance response was far greater than growth and fecundity, it seemed likely that earthworms were not able to escape from pesticide-contaminated soil into the clean soil in field and hence were exposed continuously to elevated concentrations of pesticides.

  5. An assessment of metal contamination along the Irish coast using the seaweed Ascophyllum nodosum (Fucales, Phaeophyceae)

    International Nuclear Information System (INIS)

    The relative abundance and variation of Cr, Co, Cd and Pb in Ascophyllum nodosum and intertidal surface sediments from six locations around the coast were assessed over six seasons. Higher Cd and Pb levels in Galway Docks and Cork Harbour were attributed to localised inputs of these metals from municipal and domestic waste, while at a reference site (Ballyconneely), high algal Cr concentrations were considered a function of geological setting rather than anthropogenic loading. Little seasonal variation was observed, with the exception of higher Co levels in plants in winter, associated with growth dynamics and increased fluvial inputs. In comparison with previously published data for metals in A. nodosum from the North Atlantic, with the exception of localised hot spots, the Irish coastline is still a relatively pristine environment. A. nodosum may be successfully and easily used as a biomonitor of metal contamination in coastal waters. - This paper provides details of an easily applicable, cost-effective and ecologically relevant approach to assessing the degree of metal contamination in coastal environments

  6. Risk Assessment of Heavy Metals in Abandoned Mine Lands as Signifcant Contamination Problem in Romania

    Science.gov (United States)

    Horvath, E.; Jordan, G.; Fugedi, U.; Bartha, A.; Kuti, L.; Heltai, G.; Kalmar, J.; Waldmann, I.; Napradean, I.; Damian, G.

    2009-04-01

    INTRODUCTION Wide-spread environmental contamination associated with historic mining in Europe has triggered social responses to improve related environmental legislation, the environmental assessment and management methods for the mining industry. Pollution by acid mine drainage (AMD) from ore and coal mining is the outstanding and most important source of mining-induced environmental pollution. Younger et al. (2002) estimates that watercourses polluted by coal mine drainage could be in the order of 2,000 to 3,000 km, and 1,000 to 1,500 km polluted by metal mine discharges for the EU 15 Member States (Younger et al. 2002). Significance of contamination risk posed by mining is also highlighted by mine accidents such as those in Baia Mare, Romania in 2002 and in Aznalcollar, Spain in 1999 (Jordan and D'Alessandro 2004). The new EU Mine Waste Directive (Directive 2006/21/EC) requires the risk-based inventory of abandoned mines in the EU. The cost-effective implementation of the inventory is especially demanding in countries with extensive historic mining and great number of abandoned mine sites, like Romania. The problem is further complicated in areas with trans-boundary effects. The objective of this investigation to carry out the risk-based contamination assessment of a mine site with possible trans-boundary effects in Romania. Assessment follows the source-pathway-receptor chain with a special attention to heavy metal leaching from waste dumps as sources and to transport modelling along surface water pathways. STUDY AREA In this paper the Baiut mine catchment located in the Gutai Mts., Romania, close to the Hungarian border is studied. The polymetallic deposites in the Tertiary Inner-Carpathian Volcanic Arc are exposed by a series of abandoned Zn and Pb mines first operated in the 14th century. Elevation in the high relief catchment ranges from 449m to 1044m. Geology is characterised by andesites hosting the ore deposits and paleogene sediments dominating at the

  7. Assessing the risks of nuclear and chemical contamination in the former Soviet Union

    International Nuclear Information System (INIS)

    In the first four chapters the focus is on risk assessment and the role of various segments of the society in defining risk criteria. In Chapter 2, the interface between science, policymaking, and environmental law is addressed. In chapter 3, the importance of including organizational and human factors in risk assessments is discussed. It is noted that risk assessment is also a matter for an informed public. Chapter 4 focuses on the specific application of technology to hazardous waste disposal. The most expensive high-tech equipment may not always be the best to solve a particular disposal problem. In Chapter 5 international efforts to determine the effects of nuclear testing are examined, moving on to question the methods used to define risk criteria. The last four chapters of the book focus on risk assessment and the role of various segments of the society in defining risk criteria. Chapter 6 is an introduction to the work done to assess the environmental and health affects of the 1986 accident at Chernobyl. Also the Ukrainian government's effort to assess additional natural and anthropogenic sources of radioactive contamination is discussed. In chapter 7, the efforts by the International Atomic Energy Agency and other organizations to assess the effects of Chernobyl are examined. The eighth chapter introduces the means by which nongovernmental environmental groups (NGO), e.g. Greenpeace, collect information on environmental threats and the role they play in informing the larger public about them. In this case, the dumping of radioactive waste in the Kara and Barents Seas is examined in detail. In Chapter 9 it is examined how interdisciplinary groups are required to assess the environmental and health effects of the dumping in the Kara and Barents Seas. The issues of reliable data and determining risk in the absence of data are discussed. In the final chapter, the major themes and results of the workshop are summarized, including a set of recommendations for

  8. Assessing the Vulnerability of Public-Supply Wells to Contamination: Floridan Aquifer System Near Tampa, Florida

    Science.gov (United States)

    Jagucki, Martha L.; Katz, Brian G.; Crandall, Christy A.; Eberts, Sandra M.

    2009-01-01

    This fact sheet highlights findings from the vulnerability study of a public-supply well in Temple Terrace, Florida, northeast of Tampa. The well selected for study typically produces water at the rate of 700 gallons per minute from the Upper Floridan aquifer. Water samples were collected at the public-supply well and at monitoring wells installed in or near the simulated zone of contribution to the supply well. Samples of untreated water from the public-supply wellhead contained the undesirable constituents nitrate, arsenic, uranium, radon-222, volatile organic compounds (VOCs), and pesticides, although all were detected at concentrations less than established drinking-water standards, where such standards exist. Overall, study findings point to four primary factors that affect the movement and fate of contaminants and the vulnerability of the public-supply well in Temple Terrace: (1) groundwater age (how long ago water entered, or recharged, the aquifer); (2) short-circuiting of contaminated water through sinkholes; (3) natural geochemical processes within the aquifer; and (4) pumping stress. Although the public-supply well is completed in the Upper Floridan aquifer, it produces water with concentrations of nitrate, VOCs, and the natural contaminant radon that are intermediate between the typical composition of water from the Upper Floridan aquifer and that of the overlying surficial aquifer system. Mixing calculations show that the water produced by the public-supply well could consist of upwards of 50 percent water from the surficial aquifer system mixed with water from the Upper Floridan aquifer. Anthropogenically affected water from the surficial aquifer system travels rapidly to depth through sinkholes that must be directly connected to the cavernous zone intersected by the public-supply well (and several other production wells in the region). Such solution features serve as fast pathways to the well and circumvent the natural attenuation of nitrate and

  9. Quantitative assessment of hydrocarbon contamination in soil using reflectance spectroscopy: a "multipath" approach.

    Science.gov (United States)

    Schwartz, Guy; Ben-Dor, Eyal; Eshel, Gil

    2013-11-01

    Petroleum hydrocarbons are contaminants of great significance. The commonly used analytic method for assessing total petroleum hydrocarbons (TPH) in soil samples is based on extraction with 1,1,2-Trichlorotrifluoroethane (Freon 113), a substance prohibited to use by the Environmental Protection Agency. During the past 20 years, a new quantitative methodology that uses the reflected radiation of solids has been widely adopted. By using this approach, the reflectance radiation across the visible, near infrared-shortwave infrared region (400-2500 nm) is modeled against constituents determined using traditional analytic chemistry methods and then used to predict unknown samples. This technology is environmentally friendly and permits rapid and cost-effective measurements of large numbers of samples. Thus, this method dramatically reduces chemical analytical costs and secondary pollution, enabling a new dimension of environmental monitoring. In this study we adapted this approach and developed effective steps in which hydrocarbon contamination in soils can be determined rapidly, accurately, and cost effectively solely from reflectance spectroscopy. Artificial contaminated samples were analyzed chemically and spectrally to form a database of five soils contaminated with three types of petroleum hydrocarbons (PHCs), creating 15 datasets of 48 samples each at contamination levels of 50-5000 wt% ppm (parts per million). A brute force preprocessing approach was used by combining eight different preprocessing techniques with all possible datasets, resulting in 120 different mutations for each dataset. The brute force was done based on an innovative computing system developed for this study. A new parameter for evaluating model performance scoring (MPS) is proposed based on a combination of several common statistical parameters. The effect of dividing the data into training validation and test sets on modeling accuracy is also discussed. The results of this study clearly show

  10. Methodological guide for risk assessment and management of industrial sites contaminated with radionuclides

    International Nuclear Information System (INIS)

    At the request of the French ministries of health and environment, IPSN was asked to elaborate a methodological guide for risk assessment and management of industrial sites contaminated with radionuclides. This guide is devoted to local administration, technical organisms and more generally to all the relevant stakeholders involved with the choice of a rehabilitation strategy, according to the future use of the site. The methodology to be presented is designed to fit with the different types of 'risk governance', according to circumstances: - when an industrial site is relatively small, with rather restricted zones of contamination, and no specific social concern, management may rely essentially upon radiological expertise, using generic reference levels, - when the site is larger, with spread out contamination, risk assessment and management of the site may become more controversial, namely because uncertainties remain about the effective magnitude of the contamination and no low cost solution appears to exist in view of rehabilitation. In this case, an open procedure is required, which combines technical expertise and involvement of stakeholders, in view of improving the risk assessment process as well as trying to get a better understanding of the benefits and drawbacks of different rehabilitation strategies. The methodology consists of six main steps : - Initiating the process, Pre-diagnosis, Initial diagnosis, Simplified risk assessment, Detailed risk assessment, Decision aiding in view of letting the stakeholders defining the solution appropriate to the local context. The paper will present how the risk assessment and management process can be aportionated to the importance of the problem to be solved. As far as possible, simplified risk assessment should provide information allowing the definition of the appropriate strategy. In this case, stakeholders involvement is mainly devoted to determine: - whether the site can be affected to a given use without

  11. Methodology for the Inventory and Assessment of Americium Contamination Level in 1987 in an Area of Palomares Contaminated with Plutonium Weapon Grade

    International Nuclear Information System (INIS)

    This paper presents a methodology applied for the assessment of the ''241 Am coming from the decay of ''241 Pu isotope content in a contaminated area of Palomares, where the clean-up work done in 1966, given the negligible agricultural importance of such area at the time and its geographical characteristics, was not of the same magnitude as for the rest of the region. (Author) 4 refs

  12. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Lakeview, Oregon. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    The U.S. Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (Phase I) and the Ground Water Project (Phase II). Under the UMTRA Surface Project, tailings, contaminated soil, equipment, and materials associated with the former uranium ore processing at UMTRA Project sites are placed into disposal cells. The cells are designed to reduce radon and other radiation emissions and to minimize further contamination of ground water. Surface cleanup at the UMTRA Project site near Lakeview, Oregon, was completed in 1989. The mill operated from February 1958 to November 1960. The Ground Water Project evaluates the nature and extent of ground water contamination that resulted from the uranium ore processing activities. The Ground Water Project is in its beginning stages. Human health may be at risk from exposure to ground water contaminated by uranium ore processing. Exposure could occur by drinking water pumped out of a hypothetical well drilled in the contaminated areas. Ecological risks to plants or animals may result from exposure to surface water and sediment that have received contaminated ground water. A risk assessment describes a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the ecological environment may be exposed, and the health or ecological effects that could result from that exposure. This risk assessment is a site-specific document that will be used to evaluate current and potential future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will determine whether any action is needed to protect human health or the ecological environment.

  13. Baseline risk assessment of groundwater contamination at the uranium mill tailings site near Shiprock, New Mexico. Draft

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    This report evaluates potential impact to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site were placed in a disposal cell on the site in 1986 by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This risk assessment is the first document specific to this site for the Groundwater Project. This risk assessment follows the approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed that the main contaminants in the floodplain groundwater are arsenic, magnesium, manganese, nitrate, sodium, sulfate, and uranium. The complete list of contaminants associated with the terrace groundwater could not be determined due to the lack of the background groundwater quality data. However, uranium, nitrate, and sulfate are evaluated since these chemicals are clearly associated with uranium processing and are highly elevated compared to regional waters. It also could not be determined if the groundwater occurring in the terrace is a usable water resource, since it appears to have originated largely from past milling operations. The next step in the risk assessment is to estimate how much of these contaminants people would be exposed to if a drinking well were installed in the contaminated groundwater or if there were exposure to surface expressions of contaminated water. Potential exposures to surface water include incidental contact with contaminated water or sediments by children playing on the floodplain and consumption of meat and milk from domestic animals grazed and watered on the floodplain.

  14. Baseline risk assessment of ground water contamination at the Monument Valley Uranium Mill Tailings Site, Cane Valley, Arizona. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-08-01

    This baseline risk assessment evaluates potential impact to public health or the environment from ground water contamination at the former uranium mill processing site in Cane Valley near Monument Valley, Arizona. The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project has relocated and stabilized this site`s tailings and other contaminated material in a disposal cell at Mexican Hat, Utah. The second phase of the UMTRA Project is to evaluate ground water contamination. This risk assessment is the first document specific to this site for the Ground Water Project that evaluates potential health and environmental risks. It will help determine the approach required to address contaminated ground water at the site.

  15. Baseline risk assessment of ground water contamination at the uranium mill tailings sites near Slick Rock, Colorado

    International Nuclear Information System (INIS)

    This baseline risk assessment of ground water contamination at the uranium mill tailings sites near Slick Rock, Colorado, evaluates potential public health and environmental impacts resulting from ground water contamination at the former North Continent (NC) and Union Carbide (UC) uranium mill processing sites. The tailings at these sites will be placed in a disposal cell at the proposed Burro Canyon, Colorado, site. The US Department of Energy (DOE) anticipates the start of the first phase remedial action by the spring of 1995 under the direction of the DOE's Uranium Mill Tailings Remedial Action (UMTRA) Project. The second phase of the UMTRA Project will evaluate ground water contamination. This baseline risk assessment is the first site-specific document for these sites under the Ground Water Project. It will help determine the compliance strategy for contaminated ground water at the site. In addition, surface water and sediment are qualitatively evaluated in this report

  16. Baseline risk assessment of ground water contamination at the Monument Valley Uranium Mill Tailings Site, Cane Valley, Arizona. Revision 1

    International Nuclear Information System (INIS)

    This baseline risk assessment evaluates potential impact to public health or the environment from ground water contamination at the former uranium mill processing site in Cane Valley near Monument Valley, Arizona. The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project has relocated and stabilized this site's tailings and other contaminated material in a disposal cell at Mexican Hat, Utah. The second phase of the UMTRA Project is to evaluate ground water contamination. This risk assessment is the first document specific to this site for the Ground Water Project that evaluates potential health and environmental risks. It will help determine the approach required to address contaminated ground water at the site

  17. Baseline risk assessment of ground water contamination at the uranium mill tailings sites near Slick Rock, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    1994-11-01

    This baseline risk assessment of ground water contamination at the uranium mill tailings sites near Slick Rock, Colorado, evaluates potential public health and environmental impacts resulting from ground water contamination at the former North Continent (NC) and Union Carbide (UC) uranium mill processing sites. The tailings at these sites will be placed in a disposal cell at the proposed Burro Canyon, Colorado, site. The US Department of Energy (DOE) anticipates the start of the first phase remedial action by the spring of 1995 under the direction of the DOE`s Uranium Mill Tailings Remedial Action (UMTRA) Project. The second phase of the UMTRA Project will evaluate ground water contamination. This baseline risk assessment is the first site-specific document for these sites under the Ground Water Project. It will help determine the compliance strategy for contaminated ground water at the site. In addition, surface water and sediment are qualitatively evaluated in this report.

  18. Baseline risk assessment for groundwater contamination at the uranium mill tailings site near Monument Valley, Arizona. Draft

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    This baseline risk assessment evaluates potential impact to public health or the environment resulting from groundwater contamination at the former uranium mill processing site near Monument Valley, Arizona. The tailings and other contaminated material at this site are being relocated and stabilized in a disposal cell at Mexican Hat, Utah, through the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. The tailings removal is planned for completion by spring 1994. After the tailings are removed, groundwater contamination at the site will continue to be evaluated. This risk assessment is the first document specific to this site for the Groundwater Project. It will be used to assist in determining what remedial action is needed for contaminated groundwater at the site.

  19. Development of Triad approach based system for ecological risk assessment for contaminated areas of Kyrgyzstan

    Science.gov (United States)

    Kydralieva, Kamilia; Uzbekov, Beksultan; Khudaibergenova, Bermet; Terekhova, Vera; Jorobekova, Sharipa

    2014-05-01

    This research is aimed to develop a high-effective system of an ecological risk assessment and risk-based decision making for anthropogenic ecosystems, with particular focus on the soils of the Kyrgyz Republic. The study is focused on the integration of Triad data including chemical, biological and ecotoxicological soil markers to estimate the potential risk from soils of highly anthropized areas impacted by deposition of different pollutants from mining operation. We focus on technogenic areas of Kyrgyzstan, the former uranium-producing province. Triad-based ecological risk assessment for technogenic sites are not currently used in Kyrgyzstan. However, the vitality of such research is self-evident. There are about 50 tailing dumps and more than 80 tips of radioactive waste which are formed as a result of uranium and complex ores (mercury, antimony, lead, cadmium and etc) mining around the unfavorable aforementioned places. According to the Mining Wastes' Tailings and Fills Rehabilitation Centre established in 1999 by a special Government's Resolution, one of the most ecologically dangerous uranium tailings resides in Kadzhi-Say. Although uranium processing is no longer practiced in Kadzhi-Say, a large number of open landfills and uranium ore storages still remain abandoned at the vicinity of this settlement. These neglected sites have enormous problems associated with soil erosion known as "technogenic deserts". The upper soil horizons are deprived of humus and vegetation, which favor the formation of low-buffer landscapes in the zones of maximum contamination. As a result, most of these areas are not re-cultivated and remain in critical environmental condition (Bykovchenko, et al., 2005; Tukhvatshin, 2005; Suranova, 2006). Triad data for assessing environmental risk and biological vulnerability at contaminated sites will be integrated. The following Triad-based parameters will be employed: 1) chemical soil analyses (revealing the presence of potentially dangerous

  20. Assessing groundwater surface water interaction and groundwater discharge in a contaminated site in an industrial, sub-urbanized area

    OpenAIRE

    Batlle-Aguilar, Jordi; Brouyère, Serge

    2007-01-01

    A contaminated site related to a former coke factory, located in the alluvial plain of the Meuse River near Liège was investigated to characterize the nature and extend of underground contamination. The major objective of the investigation was to evaluate whether an interaction exists, at the level of this particular site, between groundwater and surface water, despite the existence of river embankment, to assess the dynamics of such interactions and finally to quantify groundwater fluxes as ...

  1. Can Volatile Organic Metabolites Be Used to Simultaneously Assess Microbial and Mite Contamination Level in Cereal Grains and Coffee Beans?

    OpenAIRE

    Angelo C Salvador; Inês Baptista; Barros, António S.; Gomes, Newton C M; Angela Cunha; Adelaide Almeida; Silvia M Rocha

    2013-01-01

    A novel approach based on headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-ToFMS) was developed for the simultaneous screening of microbial and mite contamination level in cereals and coffee beans. The proposed approach emerges as a powerful tool for the rapid assessment of the microbial contamination level (ca. 70 min versus ca. 72 to 120 h for bacteria and fungi, respectively, using convent...

  2. Radiological risk assessment for an urban area: Focusing on an air contamination event

    International Nuclear Information System (INIS)

    This paper specifically discusses an atmospheric dispersion modeling and health risk assessment for Cs-137 to assess the potential and actual effects on human health from an inhalation event due to a radiological terrorist attack in the Seoul metropolitan area, Korea. The source term was assumed to be 5 TBq of Cs-137, introduced into the central part of Seoul's metropolitan area by a terrorist attack. Atmospheric dispersion models can be used to support the decision making and risk assessments when terrorist attacks have happened in an urban area. The concepts of Gaussian plume modeling and computational fluid dynamics modeling were used to calculate the Cs-137 concentration in the air. Mortality risk and morbid risk coefficients for the inhalation of contaminated air were used to assess the human health risk. The mortality and morbidity are 1.12E-2 and 1.64E-2, respectively in case of the Gaussian plume, while 6.23E-3 and 9.13E-3 in case of the computational fluid dynamics model. The results of the modeling are dependent on the terror scenarios and dispersion models. Accordingly, the optimization process is needed for final decision making.

  3. Fumonisin contamination of food: progress in development of biomarkers to better assess human health risks.

    Science.gov (United States)

    Turner, P C; Nikiema, P; Wild, C P

    1999-07-15

    Fumonisins, fungal toxins produced by Fusarium moniliforme, contaminate maize based foods and feeds throughout the world. They cause liver and kidney toxicity in animals in addition to leukoencephalomalacia in horses and pulmonary edema in pigs. Fumonisin B(1) is carcinogenic in rats and mice. Ecological studies have linked consumption of fumonisin contaminated maize with oesophageal cancer in human populations in South Africa and China. This review discusses the potential health risks for people exposed to the fumonisins, and describes how mechanistic studies of toxicity in animal models have allowed the development of putative biomarkers of fumonisin exposure at the individual level. The requirements for an applicable biomarker include sample availability as well as a high specificity and sensitivity for the exposure of interest. Most environmental toxic insults involve complex exposures both to other toxins and to infections; these confounding factors need to be considered in assessing both the validity of the biomarker and the exposure-disease associations. Fumonisins can be detected in the urine of animals in feeding studies but the sensitivity of the current methodology means only highly exposed people could be monitored. Mechanistic studies indicate that ceramide synthase, an enzyme involved in sphingolipid synthesis, is one cellular target for fumonisin toxicity and carcinogenicity, and this disruption to sphingolipid metabolism increases the ratio of two sphingoid precursors, sphinganine and sphingosine. The altered ratio has been observed in tissues, serum and urine for a number of animal models suggesting it as a good candidate marker of fumonisin exposure. Despite development of analytical methods to measure this biomarker there have been no studies to date correlating it to fumonisin intake in people. Given the toxic effects of fumonisins in animals and the widespread human exposure, which has been calculated to reach 440 micrograms kg(-1) body weight

  4. Evaluation and assessment of baseline metal contamination in surface sediments from the Bernam River, Malaysia.

    Science.gov (United States)

    Kadhum, Safaa A; Ishak, Mohd Yusoff; Zulkifli, Syaizwan Zahmir

    2016-04-01

    The Bernam River is one of the most important rivers in Malaysia in that it provides water for industries and agriculture located along its banks. The present study was conducted to assess the level of contamination of heavy metals (Cd, Ni, Cr, Sn, and Fe) in surface sediments in the Bernam River. Nine surface sediment samples were collected from the lower, middle, and upper courses of the river. The results indicated that the concentrations of the metals decreased in the order of Sn > Cr > Ni > Fe > Cd (56.35, 14.90, 5.3, 4.6, and 0.62 μg/g(1) dry weight). Bernam River sediments have moderate to severe enrichment for Sn, moderate for Cd, and no enrichment for Cr, Ni, and Fe. The contamination factor (CF) results demonstrated that Cd and Sn are responsible for the high contamination. The pollution load index (PLI), for all the sampling sites, suggests that the sampling stations were generally unpolluted with the exception of the Bagan Tepi Sungai, Sabak Bernam, and Tanjom Malim stations. Multivariate techniques including Pearson's correlation and hierarchical cluster analysis were used to apportion the various sources of the metals. The results suggested that the sediment samples collected from the upper course of the river had lower metal concentrations, while sediments in the middle and lower courses of the river had higher metal concentrations. Therefore, our results can be useful as a baseline data for government bodies to adopt corrective measure on the issues related to heavy metal pollution in the Bernam River in the future. PMID:26614452

  5. Validating the use of biopsy sampling in contamination assessment studies of small cetaceans.

    Science.gov (United States)

    Méndez-Fernandez, Paula; Galluzzi Polesi, Paola; Taniguchi, Satie; de O Santos, Marcos C; Montone, Rosalinda C

    2016-06-15

    Remote biopsy sampling is the most common technique for acquiring samples from free-ranging marine mammals. However, such techniques may result in variable sampling being sometimes superficial skin and blubber biopsies. For decades, blubber has been used to monitor the exposure of marine mammals to persistent organic pollutants (POPs), but little is known regarding the variability of POPs as a function of blubber depth in small cetaceans and the available literature offers variable results. Thus, the aim of the present study was to validate biopsy sampling for monitoring contaminant concentrations in small, free-ranging cetaceans. Samples from the dorsal blubber of 10 incidentally captured Atlantic spotted dolphins (Stenella frontalis) were separated into two different layers (outer and inner) to investigate the influence of sampling depth on POP concentrations. POP concentrations were compared to those of the full blubber layer. The results revealed no significant differences in lipid content between males and females or among the inner, outer and full blubber layers (p>0.05). Moreover, the wet and lipid weight concentrations of all POP classes analysed [i.e. polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs), polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), chlordanes (CHLs) and mirex] did not differ significantly with blubber depth (p>0.05). POP classes followed the same decreasing order of wet weight concentrations in blubber layers and full blubber: PCBs>DDTs>PBDEs>mirex>HCB>HCHs>CHLs. Moreover, there was a low degree of differentiation in the accumulation of POP congeners. The present findings indicated that the distribution of contaminants was homogenous with blubber depth, which validates the use of biopsy sampling for the assessment of contaminants in small cetaceans. PMID:27113024

  6. PWR circuit contamination assessment tool. Use of OSCAR code for engineering studies at EDF

    Directory of Open Access Journals (Sweden)

    Benfarah Moez

    2016-01-01

    Full Text Available Normal operation of PWR generates corrosion and wear products in the primary circuit which are activated in the core and constitute the major source of the radiation field. In addition, cases of fuel failure and alpha emitter dissemination in the coolant system could represent a significant radiological risk. Radiation field and alpha risks are the main constraints to carry out maintenance and to handle effluents. To minimize these risks and constraints, it is essential to understand the behavior of corrosion products and actinides and to carry out the appropriate measurements in PWR circuits and loop experiments. As a matter of fact, it is more than necessary to develop and use a reactor contamination assessment code in order to take into account the chemical and physical mechanisms in different situations in operating reactors or at design stage. OSCAR code has actually been developed and used for this aim. It is presented in this paper, as well as its use in the engineering studies at EDF. To begin with, the code structure is described, including the physical, chemical and transport phenomena considered for the simulation of the mechanisms regarding PWR contamination. Then, the use of OSCAR is illustrated with two examples from our engineering studies. The first example of OSCAR engineering studies is linked to the behavior of the activated corrosion products. The selected example carefully explores the impact of the restart conditions following a reactor mid-cycle shutdown on circuit contamination. The second example of OSCAR use concerns fission products and disseminated fissile material behavior in the primary coolant. This example is a parametric study of the correlation between the quantity of disseminated fuel and the variation of Iodine 134 in the primary coolant.

  7. Assessment of internal contamination of people returned to Florence after Fukushima accident and dose estimates

    International Nuclear Information System (INIS)

    Document available in abstract form only. Full text of publication follows: In this work, physical and dosimetric considerations used for the definition of the protocol for the assessment of internal contamination of people returned to Florence after Fukushima accident and related dose estimates are summarised. The protocol was developed and implemented by the Health Physics Department of Careggi University Hospital with the support of the ENEA Radiation Protection Institute and Florence Local Health Unit. This work represented the basis for my dissertation work of the Medical Physics Specialization School. On 11 March 2011, eastern Japan was struck by a 9.0-magnitude earthquake and an enormous tsunami, over 13 m in height, which together killed >20500 people and resulted in the evacuation of >320000 people from the devastated areas. The damage of the Fukushima-Daiichi nuclear power plant in consequence of the tsunami caused the release of high amounts of radionuclides, mainly 131I and 137Cs, into the atmosphere. The radioactive material was then spread out by winds reaching places far away from the nuclear power plant, included Tokyo metropolitan area where there were many Italians. Once back to Italy, the Italians who were in Japan in the days of the radioactivity release went to the hospital scared about the possible consequences on their health of the presumed internal contamination. The Maggio Musicale Fiorentino Orchestra was in tour in Japan in those days, thus involving a large number of people in potential contamination. Thus, the Careggi University Hospital of Florence became the most deeply involved centre, and it turned out to be the one that handled the largest number of people in Italy. The cooperation of ENEA Radiation Protection Institute was also given. (author)

  8. Assessment of errors caused by X-ray scatter and use of contrast medium when using CT-based attenuation correction in PET

    Energy Technology Data Exchange (ETDEWEB)

    Ay, Mohammad R. [Geneva University Hospital, Division of Nuclear Medicine, Geneva (Switzerland); Zaidi, Habib

    2006-11-15

    Quantitative image reconstruction in positron emission tomography (PET) requires an accurate attenuation map of the object under study for the purpose of attenuation correction. Current dual-modality PET/CT systems offer significant advantages over stand-alone PET, including decreased overall scanning time and increased accuracy in lesion localisation and detectability. However, the contamination of CT data with scattered radiation and misclassification of contrast medium with high-density bone in CT-based attenuation correction (CTAC) are known to generate artefacts in the attenuation map and thus the resulting PET images. The purpose of this work was to quantitatively measure the impact of scattered radiation and contrast medium on the accuracy of CTAC. Our recently developed MCNP4C-based Monte Carlo X-ray CT simulator for modelling both fan- and cone-beam CT scanners and the Eidolon dedicated 3D PET Monte Carlo simulator were used to generate realigned PET/CT data sets. The impact of X-ray scattered radiation on the accuracy of CTAC was investigated through simulation of a uniform cylindrical water phantom for both a commercial fan-beam multi-slice and a prototype cone-beam flat panel detector-based CT scanner. The influence of contrast medium was studied by simulation of a cylindrical phantom containing different concentrations of contrast medium. Moreover, an experimental study using an anthropomorphic striatal phantom was conducted for quantitative evaluation of errors arising from the presence of contrast medium by calculating the apparent recovery coefficient (ARC) in the presence of different concentrations of contrast medium. The analysis of attenuation correction factors (ACFs) for the simulated cylindrical water phantom in both fan- and cone-beam CT scanners showed that the contamination of CT data with scattered radiation in the absence of scatter removal causes underestimation of the true ACFs, namely by 7.3% and 28.2% in the centre for the two

  9. Decontamination experiment of contaminated soil and its safety assessment by residual radioactivity

    International Nuclear Information System (INIS)

    Decontamination experiment for contaminated soil was performed by using soil washing machine which were composed of soil separator and washer. For the test, the soil was grouped into low and high level and sieved as 2.0 ∼ 0.5 mm, 2.0 mm over. The experiment were done with varying soil size, radiation level, liquid/solid ratio and time. The result showed that the activity was reduced by 50-80% for 2mm soil with initial washing, while reduced to 85% from 50% for 2.0 ∼ 0.5 mm soil with repeated washing. Release criteria for the radionuclide of radioactively contaminated soil was calculated. The release criteria of Co-60, Cs-137 and Sr-90 was calculated based on dose limit of 0.25 mSv/y using D and D code which was used for decommissioning safety calculation by NRC. The results was similar to the release criteria using in USA. Radiation safety of decontaminated soil was assessed using RESRAD code and the cover depth of 10 ∼ 25 cm was required

  10. Heavy-metal-contaminated industrial soil: Uptake assessment in native plant species from Brazilian Cerrado.

    Science.gov (United States)

    Meyer, Sylvia Therese; Castro, Samuel Rodrigues; Fernandes, Marcus Manoel; Soares, Aylton Carlos; de Souza Freitas, Guilherme Augusto; Ribeiro, Edvan

    2016-08-01

    Plants of the Cerrado have shown some potential for restoration and/or phytoremediation projects due to their ability to grow in and tolerate acidic soils rich in metals. The aim of this study is to evaluate the tolerance and accumulation of metals (Cd, Cu, Pb, and Zn) in five native tree species of the Brazilian Cerrado (Copaifera langsdorffii, Eugenia dysenterica, Inga laurina, Cedrela fissilis, Handroanthus impetiginosus) subjected to three experiments with contaminated soils obtained from a zinc processing industry (S1, S2, S3) and control soil (S0). The experimental design was completely randomized (factorial 5 × 4 × 3) and conducted in a greenhouse environment during a 90-day experimentation time. The plant species behavior was assessed by visual symptoms of toxicity, tolerance index (TI), translocation factor (TF), and bioaccumulation factor (BF). C. fissilis has performed as a Zn accumulator by the higher BFs obtained in the experiments, equal to 3.72, 0.88, and 0.41 for S1, S2, and S3 respectively. This species had some ability of uptake control as a defense mechanism in high stress conditions with the best behavior for phytoremediation and high tolerance to contamination. With economical and technical benefits, this study may support a preliminary analysis necessary for using native tree species in environmental projects. PMID:26852633

  11. Assessing atmospheric concentration of polychlorinated biphenyls (PCBs) by evergreen Rhododendron maximum next to a contaminated stream

    Science.gov (United States)

    Dang, Viet D.; Walters, David; Lee, Cindy M.

    2016-01-01

    Conifers are often used as an “air passive sampler”, but few studies have focused on the implication of broadleaf evergreens to monitor atmospheric semivolatile organic compounds such as polychlorinated biphenyls (PCBs). In this study, we used Rhododendron maximum (rhododendron) growing next to a contaminated stream to assess atmospheric PCB concentrations. The study area was located in a rural setting and approximately 2 km downstream of a former Sangamo-Weston (S-W) plant. Leaves from the same mature shrubs were collected in late fall 2010, and winter and spring 2011. PCBs were detected in the collected leaves suggesting that rhododendron can be used as air passive samplers in rural areas where active sampling is impractical. Estimated ΣPCB (47 congeners) concentrations in the atmosphere decreased from fall 2010 to spring 2011 with concentration means at 3990, 2850, and 931 pg m-3 in fall 2010, winter 2011, and spring 2011, respectively. These results indicate that the atmospheric concentrations at this location continue to be high despite termination of active discharge from the former S-W plant. Leaves had a consistent pattern of high concentrations of tetra- and penta-CBs similar to the congener distribution in polyethylene (PE) passive samplers deployed in the water column suggesting that volatilized PCBs from the stream were the primary source of contaminants in rhododendron leaves.

  12. Toxicological and chemical assessment of arsenic-contaminated groundwater after electrochemical and advanced oxidation treatments.

    Science.gov (United States)

    Radić, Sandra; Crnojević, Helena; Vujčić, Valerija; Gajski, Goran; Gerić, Marko; Cvetković, Želimira; Petra, Cvjetko; Garaj-Vrhovac, Vera; Oreščanin, Višnja

    2016-02-01

    Owing to its proven toxicity and mutagenicity, arsenic is regarded a principal pollutant in water used for drinking. The objective of this study was the toxicological and chemical evaluation of groundwater samples obtained from arsenic enriched drinking water wells before and after electrochemical and ozone-UV-H2O2-based advanced oxidation processes (EAOP). For this purpose, acute toxicity test with Daphnia magna and chronic toxicity test with Lemna minor L. were employed as well as in vitro bioassays using human peripheral blood lymphocytes (HPBLs). Several oxidative stress parameters were estimated in L.minor. Physicochemical analysis showed that EAOP treatment was highly efficient in arsenic but also in ammonia and organic compound removal from contaminated groundwater. Untreated groundwater caused only slight toxicity to HPBLs and D. magna in acute experiments. However, 7-day exposure of L. minor to raw groundwater elicited genotoxicity, a significant growth inhibition and oxidative stress injury. The observed genotoxicity and toxicity of raw groundwater samples was almost completely eliminated by EAOP treatment. Generally, the results obtained with L. minor were in agreement with those obtained in the chemical analysis suggesting the sensitivity of the model organism in monitoring of arsenic-contaminated groundwater. In parallel to chemical analysis, the implementation of chronic toxicity bioassays in a battery is recommended in the assessment of the toxic and genotoxic potential of such complex mixtures. PMID:26580737

  13. Contamination assessment of mercury and arsenic in roadway dust from Baoji, China

    Science.gov (United States)

    Lu, Xinwei; Li, Loretta Y.; Wang, Lijun; Lei, Kai; Huang, Jing; Zhai, Yuxiang

    The physicochemical properties and the contamination levels of mercury and arsenic in roadway dust from Baoji, NW China were investigated using an Atomic Fluorescence Spectrophotometer. Contamination levels were assessed based on the geoaccumulation index and the enrichment factor. The results show that magnetic susceptibilities of roadway dust were higher than Holocene loess-soil of central Shaanxi Loess Plateau. The mean contents of organic matter, PM10 and PM100 were 8.8%, 21.8% and 98.6%, respectively. Mercury concentration ranged from 0.48 to 2.32 μg g -1, with a mean value of 1.11 μg g -1, 17.1 times the Chinese soil mercury background value and 37 times the Shaanxi soil mercury background value. Arsenic concentration ranged from 9.0 to 42.8 μg g -1, with a mean value of 19.8 μg g -1, 1.8 times the Chinese and Shaanxi soil arsenic background values. The geoaccumlation index and enrichment factor indicate that mercury in the dust mainly originated from anthropogenic sources with ratings of "strongly polluted" and "strongly to extremely polluted", whereas arsenic in dust originated from both natural and anthropogenic sources, with a ratings of "moderately to strongly polluted" and "strongly polluted". Industrial activities, such as a coal-fired power station, coke-oven plant, and cement manufacturing plant, augmented by vehicular traffic, are the anthropogenic sources of mercury and arsenic in the roadway dust.

  14. Assessment of co-contaminant effects on uranium and thorium speciation in freshwater using geochemical modelling.

    Science.gov (United States)

    Lofts, Stephen; Fevrier, Laureline; Horemans, Nele; Gilbin, Rodolphe; Bruggeman, Christophe; Vandenhove, Hildegarde

    2015-11-01

    Speciation modelling of uranium (as uranyl) and thorium, in four freshwaters impacted by mining activities, was used to evaluate (i) the influence of the co-contaminants present on the predicted speciation, and (ii) the influence of using nine different model/database combinations on the predictions. Generally, co-contaminants were found to have no significant effects on speciation, with the exception of Fe(III) in one system, where formation of hydrous ferric oxide and adsorption of uranyl to its surface impacted the predicted speciation. Model and database choice on the other hand clearly influenced speciation prediction. Complexes with dissolved organic matter, which could be simulated by three of the nine model/database combinations, were predicted to be important in a slightly acidic, soft water. Model prediction of uranyl and thorium speciation needs to take account of database comprehensiveness and cohesiveness, including the capability of the model and database to simulate interactions with dissolved organic matter. Measurement of speciation in natural waters is needed to provide data that may be used to assess and improve model capabilities and to better constrain the type of predictive modelling work presented here. PMID:26225834

  15. Interrenal dysfunction in fish from contaminated sites: In vivo and in vitro assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hontela, A. [Univ. du Quebec, Montreal, Quebec (Canada)

    1998-01-01

    Cortisol, synthesized in the interrenal cells of teleost head kidney, has a major role in the physiologic response to physical and chemical stressors. Plasma levels of cortisol increase in physiologically competent fish acutely exposed to stressors such as cadmium or mercury. The effects of chronic low level exposures are less well understood. The author has diagnosed an endocrine impairment characterized by a reduced capacity to elevate plasma cortisol levels in response to an acute standardized capture stress in yellow perch (Perca flavescens) and in northern pike (Esox lucius) sampled at sites contaminated by mixtures of pollutants (heavy metals, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls), by heavy metals, or by bleached kraft mill effluent. The studies with fish, as well as with amphibians at contaminated sites, demonstrated that low level chronic exposures impair secretion of corticosteroids. The author has developed new tests for assessment of the functional integrity of teleost and amphibian interrenal tissue using an adrenocorticotropic hormone (ACTH) challenge, in vivo and in vitro. The reduced ability to respond to ACTH indicates that the normal neuroendocrine response to stressors may be disrupted and that the ability to cope with biotic and abiotic stressors in the environment may be significantly reduced in the impaired animals.

  16. Avoidance tests with Folsomia candida for the assessment of copper contamination in agricultural soils

    International Nuclear Information System (INIS)

    The feasibility of assessing copper accumulation in agricultural soils using avoidance tests with a Canadian strain of Folsomia candida was investigated under laboratory conditions. The avoidance response to nominal copper sulfate concentrations of 0, 200, 800, 1600 and 3200 mg kg-1 in OECD soil was inconsistent between trials with the standard plastic cup or a modified Petri dish method requiring less soil. However, combined results from three Petri dish trials decreased variability and provided a 75% avoidance level, close to the 80% criterion proposed for avoidance tests. A Copper avoidance EC50s of 18 mg kg-1was obtained using the Petri dish method whether tests were conducted with or without light. While Petri dish tests have potential as a cheap tool to distinguish metal contaminated soils from uncontaminated soils they would be unsuitable for tracking or quantifying changes in metal concentrations. throughout remediation. Advantages and limitations of the method have been presented. - Research highlights: → Avoidance cup test using Folsomia candida detects Cu independently of concentration. → Improved avoidance Petri dish test detects Cu in soil in function of concentration. → Cu voidance tests had similar EC50 values whether conducted with or without light. → Combining Cu avoidance test trials in OECD soil reduced the variability of results. - Improved avoidance tests having an EC50 value similar to the background Cu concentration in uncontaminated agricultural soils can distinguish Cu contaminated and Cu free OECD soil.

  17. Assessment of the intrinsic vulnerability to groundwater contamination in lahore, pakistan

    International Nuclear Information System (INIS)

    This study was intended to map intrinsic vulnerability of groundwater contamination in Lahore using GIS based DRASTIC model. The final output of DRASTIC model was reclassified into three equal interval classes, corresponding to low, moderate and high vulnerability regions. Most of the study area was found to have low to moderate vulnerability, with 27.48% area of low, 66.48% of moderate and only 6.04% area of high vulnerability. Most of the drinking water wells are installed in the residential area of the city, which shows low chances of contamination due to deep water table and almost no recharge. However, an industrial drain is located in the high vulnerable area in the southeastern part of the study area. The previous studies are in agreement with vulnerability zones. Further to remove any doubt in the suitability of assigned weight, map removal sensitivity analysis had been carried out. The assessment of the sensitivity analysis had been made through visual as well as quantitative methods. Priority order for contribution of the parameters in the vulnerability for the study area is D>I>C>R>A>T>S. (author)

  18. Assessing atmospheric concentration of polychlorinated biphenyls by evergreen Rhododendron maximum next to a contaminated stream.

    Science.gov (United States)

    Dang, Viet D; Walters, David M; Lee, Cindy M

    2016-09-01

    Conifers are often used as an air passive sampler, but few studies have focused on the implication of broadleaf evergreens to monitor atmospheric semivolatile organic compounds such as polychlorinated biphenyls (PCBs). In the present study, the authors used Rhododendron maximum (rhododendron) growing next to a contaminated stream to assess atmospheric PCB concentrations. The present study area was located in a rural setting and approximately 2 km downstream of a former capacitor plant. Leaves from the same mature shrubs were collected in late fall 2010 and winter and spring 2011. Polychlorinated biphenyls were detected in the collected leaves, suggesting that rhododendron can be used as air passive samplers in rural areas where active sampling is impractical. Estimated ΣPCB (47 congeners) concentrations in the atmosphere decreased from fall 2010 to spring 2011 with concentration means at 3990 pg m(-3) , 2850 pg m(-3) , and 931 pg m(-3) in fall 2010, winter 2011, and spring 2011, respectively. These results indicate that the atmospheric concentrations at this location continue to be high despite termination of active discharge from the former industrial source. Leaves had a consistent pattern of high concentrations of tetra-CBs and penta-CBs similar to the congener distribution in polyethylene passive samplers deployed in the water column, suggesting that volatilized PCBs from the stream were the primary source of contaminants in rhododendron leaves. Environ Toxicol Chem 2016;35:2192-2198. © 2016 SETAC. PMID:26889751

  19. Concentrations, distribution, sources and risk assessment of organohalogenated contaminants in soils from Kenya, Eastern Africa.

    Science.gov (United States)

    Sun, Hongwei; Qi, Yueling; Zhang, Di; Li, Qing X; Wang, Jun

    2016-02-01

    The organohalogenated contaminants (OCs) including 12 organochlorine pesticides (OCPs), 7 indicator polychlorinated biphenyls (PCBs) and 7 polybrominated diphenyl ethers (PBDEs) were determined in soils collected from Kenya, Eastern Africa. The total OCPs fell in the range of n.d-49.74 μg kg(-1) dry weight (dw), which was dominated by DDTs and endosulfan. Identification of pollution sources indicated new input of DDTs for malaria control in Kenya. The total PCBs ranged from n.d. to 55.49 μg kg(-1) dw, dominated by penta- and hexa-PCBs, probably associated with the leakage of obsolete transformer oil. The soils were less contaminated by PBDEs, ranging from 0.19 to 35.64 μg kg(-1) dw. The predominant PBDE congeners were penta-, tri- or tetra-BDEs, varying among different sampling sites. Risk assessment indicated potential human health risks posed by OCs in soils from Kenya, with PCBs as the most contributing pollutants. The local authorities are recommended to make best efforts on management of OC pollution, particularly from DDTs and PCBs to meet the requirement of Stockholm Convention. PMID:26686059

  20. Contamination monitoring: problems and solutions

    International Nuclear Information System (INIS)

    Contamination monitoring is discussed under the following headings: case for contamination monitoring; regulations, rules, and permissible levels; the new xenon filled detector probe; types of monitors fitted with this probe; assessment of alpha contamination; and assessment of tritium contamination

  1. Attenuation of Upper Body Accelerations during Gait: Piloting an Innovative Assessment Tool for Parkinson’s Disease

    OpenAIRE

    2015-01-01

    The objective of the current investigation was to explore whether upper body accelerations obtained during gait provide sensitive measures of postural control in people with Parkinson's disease (PD). Thirteen people with PD (70 ± 11 years) and nineteen age-matched controls (70 ± 7 years) walked continuously for two minutes while wearing three inertial sensors located on their lower back (L5), shoulder level (C7), and head. Magnitude (root mean square (RMS)), attenuation (attenuation coefficie...

  2. Assessing the measurement of aerosol single scattering albedo by Cavity Attenuated Phase-Shift Single Scattering Monitor (CAPS PMssa)

    Science.gov (United States)

    Perim de Faria, Julia; Bundke, Ulrich; Onasch, Timothy B.; Freedman, Andrew; Petzold, Andreas

    2016-04-01

    The necessity to quantify the direct impact of aerosol particles on climate forcing is already well known; assessing this impact requires continuous and systematic measurements of the aerosol optical properties. Two of the main parameters that need to be accurately measured are the aerosol optical depth and single scattering albedo (SSA, defined as the ratio of particulate scattering to extinction). The measurement of single scattering albedo commonly involves the measurement of two optical parameters, the scattering and the absorption coefficients. Although there are well established technologies to measure both of these parameters, the use of two separate instruments with different principles and uncertainties represents potential sources of significant errors and biases. Based on the recently developed cavity attenuated phase shift particle extinction monitor (CAPS PM_{ex) instrument, the CAPS PM_{ssa instrument combines the CAPS technology to measure particle extinction with an integrating sphere capable of simultaneously measuring the scattering coefficient of the same sample. The scattering channel is calibrated to the extinction channel, such that the accuracy of the single scattering albedo measurement is only a function of the accuracy of the extinction measurement and the nephelometer truncation losses. This gives the instrument an accurate and direct measurement of the single scattering albedo. In this study, we assess the measurements of both the extinction and scattering channels of the CAPS PM_{ssa through intercomparisons with Mie theory, as a fundamental comparison, and with proven technologies, such as integrating nephelometers and filter-based absorption monitors. For comparison, we use two nephelometers, a TSI 3563 and an Aurora 4000, and two measurements of the absorption coefficient, using a Particulate Soot Absorption Photometer (PSAP) and a Multi Angle Absorption Photometer (MAAP). We also assess the indirect absorption coefficient

  3. Assessment of the potential radiological impact of residual contamination in the Maralinga and Emu areas

    International Nuclear Information System (INIS)

    The report presents an assessment of potential doses to future inhabitants of the Maralinga and Emu areas of Southern Australia, where nuclear weapons tests in the 1950s and 1960s resulted in widespread residual radioactive contamination. Annual effective doses of several millisieverts would be expected to result from continual occupancy within contours enclosing areas of several hundred square kilometres. Larger predicted annual effective doses - of the order of 0.5 Sv -would be expected to occur from 100% occupancy in small regions immediately surrounding the test sites, but continual occupancy of such areas is highly unlikely because of their small size. The most significant dose pathways are inhalation of resuspended activity and ingestion of soil by infants. An analysis of the effects of uncertainties in the dose calculation indicated the uncertainty distribution on predicted doses from the inhalation pathway. (author)

  4. Assessment of parasitic contamination of raw vegetables in Mannuthy, Kerala state, India

    Directory of Open Access Journals (Sweden)

    B. Sunil

    2014-04-01

    Full Text Available Aim: To assess the parasitic contamination of raw vegetables retailed at Mannuthy in Thrissur district of Kerala state, India. Materials and Methods: A total of 112 samples, viz. cabbage (17, mint (11, coriander leaves (11, spinach (15, onion (10, carrot (10, potato (10, ginger (15, beet root (7 and tomato (6 were collected from retail market at Mannuthy, Kerala. Collected samples were washed with physiological saline solution. The washings were collected and examined under light microscopy. Results: Helminthic eggs were detected in three (2.7% of 112 samples. Two samples of cabbage (1.8% and one sample of onion (0.9% was positive for ova of Ascaris spp. Conclusion: Vegetables can act as potential source of gastrointestinal parasitic infections. The study emphasizes the need for proper washing of vegetables before they are consumed or cooked.

  5. Biosensor-based diagnostics of contaminated groundwater: assessment and remediation strategy

    International Nuclear Information System (INIS)

    Shallow groundwater beneath a former airfield site in southern England has been heavily contaminated with a wide range of chlorinated solvents. The feasibility of using bacterial biosensors to complement chemical analysis and enable cost-effective, and focussed sampling has been assessed as part of a site evaluation programme. Five different biosensors, three metabolic (Vibrio fischeri, Pseudomonas fluorescens 10568 and Escherichia coli HB101) and two catabolic (Pseudomonas putida TVA8 and E. coli DH5α), were employed to identify areas where the availability and toxicity of pollutants is of most immediate environmental concern. The biosensors used showed different sensitivities to each other and to the groundwater samples tested. There was generally a good agreement with chemical analyses. The potential efficacy of remediation strategies was explored by coupling sample manipulation to biosensor tests. Manipulation involved sparging and charcoal treatment procedures to simulate remediative engineering solutions. Sparging was sufficient at most locations. - Luminescent bacteria complement chemical analysis and support remediation technology

  6. Assessment of toxicity of heavy metal contaminated soils for Collembola in the field and laboratory

    DEFF Research Database (Denmark)

    Xu, Jie; Krogh, Paul Henning; Luo, Yongming;

    2008-01-01

    We present a field and laboratory investigation of effects of increasing levels of heavy metal contamination on the biodiversity and performance of collembolans. A 40 year old pollution with Cu, Zn, Pb and Cd pollution due to Cu smelting over 40 years was investigated in a paddy field area of...... Zhejiang province, Fuyang county. We addressed the questions: 1) how do different collembolan life-forms respond to heavy metals in long-time pollution field site. 2) Are laboratory toxicity testing of field collected polluted soil predictable for the population effects observed in aged heavy metal...... pollutions. Effects of the heavy metals in the soil from the paddy fields were assessed for growth, survival and reproduction under laboratory conditions. For the tests we used two soil arthropod species: the parthenogenetic, Folsomia candida Willem 1902, and the sexually reproducing, Sinella curviseta Brook...

  7. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Sites near Rifle, Colorado. Revision 2

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (Phase I) and the Ground Water Project (Phase II). Under the UMTRA Surface Project, tailings, radioactive contaminated soil, equipment, and materials associated with the former uranium ore processing sites are placed into disposal cells. The cells are designed to reduce radon and other radiation emissions and to prevent further ground water contamination. The Ground Water Project evaluates the nature and extent of ground water contamination resulting from the uranium ore processing activities. Two UMTRA Project sites are near Rifle, Colorado: the Old Rifle site and the New Rifle site. Surface cleanup at the two sites is under way and is scheduled for completion in 1996. The Ground Water Project is in its beginning stages. A risk assessment identifies a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the environment may be exposed, and the health or environmental effects that could result from that exposure. This report is a site-specific document that will be used to evaluate current and future impacts to the public and the environment from exposure to contaminated ground water. This evaluation and further site characterization will be used to determine if action is needed to protect human health or the environment. Human health risk may result from exposure to ground water contaminated from uranium ore processing. Exposure could occur from drinking water obtained from a well placed in the areas of contamination. Furthermore, environmental risk may result from plant or animal exposure to surface water and sediment that have received contaminated ground water

  8. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Sites near Rifle, Colorado. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    The U.S. Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (Phase I) and the Ground Water Project (Phase II). Under the UMTRA Surface Project, tailings, radioactive contaminated soil, equipment, and materials associated with the former uranium ore processing sites are placed into disposal cells. The cells are designed to reduce radon and other radiation emissions and to prevent further ground water contamination. The Ground Water Project evaluates the nature and extent of ground water contamination resulting from the uranium ore processing activities. Two UMTRA Project sites are near Rifle, Colorado: the Old Rifle site and the New Rifle site. Surface cleanup at the two sites is under way and is scheduled for completion in 1996. The Ground Water Project is in its beginning stages. A risk assessment identifies a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the environment may be exposed, and the health or environmental effects that could result from that exposure. This report is a site-specific document that will be used to evaluate current and future impacts to the public and the environment from exposure to contaminated ground water. This evaluation and further site characterization will be used to determine if action is needed to protect human health or the environment. Human health risk may result from exposure to ground water contaminated from uranium ore processing. Exposure could occur from drinking water obtained from a well placed in the areas of contamination. Furthermore, environmental risk may result from plant or animal exposure to surface water and sediment that have received contaminated ground water.

  9. Application of data fusion in human health risk assessment for hydrocarbon mixtures on contaminated sites

    International Nuclear Information System (INIS)

    The exposure and toxicological data used in human health risk assessment are obtained from diverse and heterogeneous sources. Complex mixtures found on contaminated sites can pose a significant challenge to effectively assess the toxicity potential of the combined chemical exposure and to manage the associated risks. A data fusion framework has been proposed to integrate data from disparate sources to estimate potential risk for various public health issues. To demonstrate the effectiveness of the proposed data fusion framework, an illustrative example for a hydrocarbon mixture is presented. The Joint Directors of Laboratories Data Fusion architecture was selected as the data fusion architecture and Dempster–Shafer Theory (DST) was chosen as the technique for data fusion. For neurotoxicity response analysis, neurotoxic metabolites toxicological data were fused with predictive toxicological data and then probability-boxes (p-boxes) were developed to represent the toxicity of each compound. The neurotoxic response was given a rating of “low”, “medium” or “high”. These responses were then weighted by the percent composition in the illustrative F1 hydrocarbon mixture. The resulting p-boxes were fused according to DST's mixture rule of combination. The fused p-boxes were fused again with toxicity data for n-hexane. The case study for F1 hydrocarbons illustrates how data fusion can help in the assessment of the health effects for complex mixtures with limited available data

  10. Application of data fusion in human health risk assessment for hydrocarbon mixtures on contaminated sites.

    Science.gov (United States)

    Dyck, Roberta; Islam, M Shafiqul; Zargar, Amin; Mohapatra, Asish; Sadiq, Rehan

    2013-11-16

    The exposure and toxicological data used in human health risk assessment are obtained from diverse and heterogeneous sources. Complex mixtures found on contaminated sites can pose a significant challenge to effectively assess the toxicity potential of the combined chemical exposure and to manage the associated risks. A data fusion framework has been proposed to integrate data from disparate sources to estimate potential risk for various public health issues. To demonstrate the effectiveness of the proposed data fusion framework, an illustrative example for a hydrocarbon mixture is presented. The Joint Directors of Laboratories Data Fusion architecture was selected as the data fusion architecture and Dempster-Shafer Theory (DST) was chosen as the technique for data fusion. For neurotoxicity response analysis, neurotoxic metabolites toxicological data were fused with predictive toxicological data and then probability-boxes (p-boxes) were developed to represent the toxicity of each compound. The neurotoxic response was given a rating of "low", "medium" or "high". These responses were then weighted by the percent composition in the illustrative F1 hydrocarbon mixture. The resulting p-boxes were fused according to DST's mixture rule of combination. The fused p-boxes were fused again with toxicity data for n-hexane. The case study for F1 hydrocarbons illustrates how data fusion can help in the assessment of the health effects for complex mixtures with limited available data. PMID:23219588

  11. Preliminary contamination hazard assessment of land resources in Central Bekaa plain of Lebanon

    International Nuclear Information System (INIS)

    The Central Bekaa plain constitutes the main region with prime agricultural land in Lebanon. The agricultural sector is the main consumer of available water resources (up to70%). Intensive agriculture, urban expansion and industrial activity have been increasingly stressing the limited soil and water resources. In the Central Bekaa, farmers are enforced to use contaminated water to recompense water shortage during the peak crop demands. Water scarcity and mismanagement increased contagion hazards and pressure on soil and groundwater quality. The objective of this study was to provide a synopsis of the assessment methodologies and analyze the soil-groundwater vulnerability to contamination by heavy metals as based on the risks of metal transfer and the degree of protection offered by the soil cover and soil-metal interaction. The soils of the area are distinguished by a high content of clay and relatively high pH that would reduce the danger of heavy metals transfer and mobility. However, throughout the study area, the perched groundwater table is relatively high with a depth varying between 60 and 500 cm making it highly vulnerable to pollution. Metals might be more mobile under reducing conditions. The area of high, medium and low soil and groundwater table vulnerability were determined and spatially located according to international standards. Referring to the German Concept on soil protection effectiveness, the residence time of percolating water carrying soluble pollutants in the unsaturated soil zone was assessed. It varied between several months and 10 years. Zones of high soil and ground water vulnerability risk require special management to establish pollution prevention programs. Results can help land use planning oriented to the choice of suitable crops, promulgate sustainable use of natural resources and environmental preservation. (author)

  12. Assessing the bioavailability of organic contaminants using a novel bioluminescent biosensor

    International Nuclear Information System (INIS)

    The limited rate and extent of biodegradation in contaminated soils is often attributed to a lack of bioavailability of hydrophobic organic compounds. To date, the majority of studies aimed at assessing bioavailability and modes of bacterial uptake have relied upon quantification of microbial degradation rates in comparison to rates of dissolution or desorption in corresponding abiotic systems. Several studies have indicated the possibility of a direct uptake mechanism for sorbed or separate phase compounds. However, there is a lack of direct evidence to support these claims. To address the need for a direct measurement technique for microbial bioavailability, we have constructed a whole-cell bioluminescent biosensor, Pseudomonas putida F1G4 (PpF1G4), by fusing lux genes that encode for bioluminescence to the solvent efflux pump (sep) promoter element in PpF1G4, which is induced by the presence of target organic compounds. When the biosensor microorganism is exposed to an inducing compound, the bioluminescence system is activated and the cell produces an intensity of visible light (λ = 495 nm) that is directly related to the level of exposure to the contaminant. Batch experiments were carried out to assess whether the biosensor is able to sense the presence of toluene, a representative target compound, contained in a NAPL. Preliminary results show that while PpF1G4 responds to toluene in the aqueous phase, the biosensor does not appear to emit a significant bioluminescence signal in response to the toluene present in the NAPL. Ongoing research is focusing on optimizing the experimental procedure to fully explore this issue. (author)

  13. Evaluating the applicability of regulatory leaching tests for assessing lead leachability in contaminated shooting range soils.

    Science.gov (United States)

    Cao, Xinde; Dermatas, Dimitris

    2008-04-01

    The toxicity characteristic leaching procedure (TCLP) is the current US-EPA standard protocol to evaluate metal leachability in wastes and contaminated soils. However, application of TCLP to assess lead (Pb) leachability from contaminated shooting range soils may be questionable. This study determined Pb leachability in the range soils using TCLP and another US-EPA regulatory leaching method, synthetic precipitation leaching procedure (SPLP). Possible mechanisms that are responsible for Pb leaching in each leaching protocol were elucidated via X-ray diffraction (XRD). Soil samples were collected from the backstop berms at four shooting ranges, with Pb concentrations ranging from 5,000 to 60,600 mg kg(-1) soil. Lead concentrations in the TCLP leachates were from 3 to 350 mg l(-1), with all but one soil exceeding the USEPA non-hazardous waste disposal limit of 5 mg l(-1). However, continued dissolution of metallic Pb particles from spent Pb bullets and its re-precipitation as cerussite (PbCO(3)) prevented the TCLP extraction from reaching equilibrium at the end of the standard leaching period (18 h). Thus, the standard one-point TCLP test would either over- or under-estimate Pb leachability in shooting range soils. Lead concentration in the SPLP leachates ranged from 0.021 to 2.6 mg l(-1), with all soils above the USEPA regulatory limit of 0.015 mg l(-1). In contrast to TCLP, SPLP leaching had reached equilibrium, with regard to both pH and Pb concentrations, within the standard 18 h leaching period, and the analytical SPLP results were in good agreement with those derived from modeling. Thus, we concluded that SPLP is a more appropriate alternative than TCLP for assessing lead leachability in range soils. PMID:18204911

  14. Groundwater contamination and risk assessment of industrial complex in Busan Metropolitan City, Korea

    Science.gov (United States)

    Hamm, S.-Y.; Ryu, S. M.; Cheong, J.-Y.; Woo, Y.-J.

    2003-04-01

    In Korea, the potential of groundwater contamination in urban areas is increasing by industrial and domestic waste waters, leakage from oil storage tanks and sewage drains, leachate from municipal landfill sites and so on. Nowadays, chlorinated organic compounds such as trichloroethylene (TCE) and tetrachloroethylene (PCE), which are driving residential area as well as industrial area, are recognized as major hazardous contaminants. As well known, TCE is wisely used industrial activities such as degreasing, metal stripping, chemical manufacturing, pesticide production, coal gasification plants, creosote operation, and also used in automobile service centers, photo shops and laundries as cleaning solvent. Thus, groundwater protection in urban areas is important issue in Korea This study is to understand groundwater quality and contamination characteristics and to estimate risk assessment in Sasang industrial complex, Busan Metropolitan City. Busan Metropolitan City is located on southeastern coast of the Korean peninsula and is the second largest city in South Korea with a population of 3.8 millions. The geology of the study area is composed of andesite, andesitic tuff, biotite granite and alluvium (Kim et al., 1998). However, geology cannot be identified on the surface due to pavement and buildings. According to drill logs in the study area, the geologic section consists in landfill, fine sand, clay, gravelly clay, and biotite granite from the surface. Biotite granite appears 5.5- 6 m depth. Groundwater samples were collected at twenty sites in Sasang industrial complex. The groundwater samples are plotted on Piper's trilinear diagram, which indicates Ca-Cl2 type. The groundwater may be influenced by salt water because Sasang industrial complex is located near the mouse of Nakdong river that flows to the South Sea. The Ca-Cl2 water type may be partly influenced by anthropogenic contamination in the study area, since water type in granite area generally belongs Ca

  15. Cumulative risk assessment for plasticizer-contaminated food using the hazard index approach

    International Nuclear Information System (INIS)

    Phthalates strongly and adversely affect reproduction, development and liver function. We did a cumulative risk assessment for simultaneous exposure to nine phthalates using the hazard index (HI) and the levels of nine phthalates in 1200 foodstuff samples. DEHP (di-2-ethylhexyl phthalate) present the highest level (mean: 0.443 mg/kg) in 1200 samples, and the highest average daily dose (ADD) was found in DEHP, ΣDBP(i + n) (the sum of dibutyl phthalate [DBP] isomers [DnBP + DiBP]) posed the highest risk potential of all the phthalates. In seven phthalates, the 95th percentiles of the ADDs for ΣDBP(i + n) in 0–6-yr-old children accounted for 91% (79–107%) of the tolerable daily intake, and the 95th percentiles of the HIs for the anti-androgenic effects of five phthalates in 0–3-yr-old children and 4–6-yr-old girls were >1. We conclude that the health of younger Taiwanese may be adversely affected by overexposure of phthalate-contaminated foods. - Graphical abstract: In seven phthalates, the 95th percentile of the average daily dose (ADD) for ΣDBP(i + n) (the sum of dibutyl phthalate [DBP] isomers [DnBP + DiBP]) in 0–3-yr-old male (0–3 M) and female (0–3 F) children accounted for 97% and 84% of TDIs, respectively. For 4–6-yr-old and 7–12-yr-old males and 7–12-yr-old females, ADDs for ΣDBP(i + n) accounted for 79%, 72%, and 65% of TDIs, respectively. - Highlights: • A cumulative risk assessment of PAEs was used in a severe plasticizer-contaminated food episode. • ΣDBP(i + n) posed the highest risk potential of all the dietary phthalates. • Females 4–6 yr old had the highest risk for anti-androgenic effects. • Beverages, milk and dairy products were the major contributors to average daily dose of phthalate esters. - The health of young Taiwanese may be adversely affected by overexposure of plasticizer-contaminated food

  16. Assessment of sites concerning radioactive contamination during preparation of a Contamination Site Register; Bewertung der radiologischen Altlastenrelevanz von gewerblichen und industriellen Standorten

    Energy Technology Data Exchange (ETDEWEB)

    Gellermann, Rainer [Nuclear Control and Consulting GmbH, Braunschweig (Germany); Flesch, Klaus [Saechsisches Landesamt fuer Umwelt, Landwirtschaft und Geologie (LfULG), Dresden (Germany)

    2014-07-01

    Experience gained since 1990 in the new, but also old German Federal States has shown that there are radioactive contaminated sites beside the legacies of uranium mining in Germany which caused exposures exceeding the radiation protection limits for members of the public. The reason for this situation is that radioactivity has been excluded in the compilation of the register for potentially hazardous sites that are prepared routinely in the context of soil protection assessments. Moreover, the information contained in these registers is not yet evaluated regarding aspects of radioactivity. In many cases, the information existing at the soil protection authorities needs only to be additionally filtered in order to identify potentially hazardous sites for radioactive contamination. For that reason, the working group ''Natural radioactivity'' (AKNAT) of the German-Swiss Radiation Protection Association developed a specific catalogue of business branches that provides indications for radioactive legacies.

  17. Baseline risk assessment of ground water contamination at the uranium mill tailings sites near Rifle, Colorado. Revision 1

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (Phase 1) and the Ground Water Project (Phase 2). Under the UMTRA Surface Project, tailings, radioactive contaminated soil, equipment, and materials associated with the former uranium ore processing sites are placed into disposal cells. The cells are designed to reduce radon and other radiation emissions and to prevent further ground water contamination. The Ground Water Project evaluates the nature and extent of ground water contamination resulting from the uranium ore processing activities. Two UMTRA Project sites are near Rifle, Colorado: the Old Rifle site and the New Rifle site. Surface cleanup at the two sites is under way and is scheduled for completion in 1996. The Ground Water Project is in its beginning stages. A risk assessment identifies a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the environment may be exposed, and the health or environmental effects that could result from that exposure. This report is a site-specific document that will be used to evaluate current and future impacts to the public and the environment from exposure to contaminated ground water. This evaluation and further site characterization will be used to determine if action is needed to protect human health or the environment

  18. Baseline risk assessment of ground water contamination at the uranium mill tailings sites near Rifle, Colorado. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (Phase 1) and the Ground Water Project (Phase 2). Under the UMTRA Surface Project, tailings, radioactive contaminated soil, equipment, and materials associated with the former uranium ore processing sites are placed into disposal cells. The cells are designed to reduce radon and other radiation emissions and to prevent further ground water contamination. The Ground Water Project evaluates the nature and extent of ground water contamination resulting from the uranium ore processing activities. Two UMTRA Project sites are near Rifle, Colorado: the Old Rifle site and the New Rifle site. Surface cleanup at the two sites is under way and is scheduled for completion in 1996. The Ground Water Project is in its beginning stages. A risk assessment identifies a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the environment may be exposed, and the health or environmental effects that could result from that exposure. This report is a site-specific document that will be used to evaluate current and future impacts to the public and the environment from exposure to contaminated ground water. This evaluation and further site characterization will be used to determine if action is needed to protect human health or the environment.

  19. Changes in metal contamination levels in estuarine sediments around India – An assessment

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, P.; Ramteke, D.; Chakraborty, S.; Nath, B.N.

    the west coast. Sediments from those estuaries were found to be more contaminated by metals on which major cities are located. An improvement in estuarine sediment quality (in terms of metal contamination) over time around India was noticed. This study...

  20. Functional Mechanism of Lung Mosaic CT Attenuation: Assessment with Deep-Inspiration Breath-Hold Perfusion SPECT-CT Fusion Imaging and Non-Breath-Hold Technegas SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Suga, K.; Yasuhiko, K. (Dept. of Radiology, St. Hill Hospital, Ube, Yamaguchi (Japan)); Iwanaga, H.; Tokuda, O.; Matsunaga, N. (Dept. of Radiology, Yamaguchi Univ. School of Medicine, Ube, Yamaguchi (Japan))

    2009-01-15

    Background: The functional mechanism of lung mosaic computed tomography attenuation (MCA) in pulmonary vascular disease (PVD) and obstructive airway disease (OAD) has not yet been fully clarified. Purpose: To clarify the mechanism of MCA in these diseases by assessing the relationship between regional lung function and CT attenuation change at MCA sites with the use of automated deep-inspiratory breath-hold (DIBrH) perfusion single-photon emission computed tomography (SPECT)-CT fusion images and non-breath-hold Technegas SPECT. Material and Methods: Subjects were 42 PVD patients (31 pulmonary thromboembolism, four primary/two secondary pulmonary hypertension, and five Takayasu arteritis), 12 OAD patients (five acute asthma, four obliterative bronchiolitis, and three bronchiectasis), and 12 normal controls, all of whom had MCA on DIBrH CT. The relationship between regional lung function and CT attenuation change at the lung slices with MCA was assessed using DIBrH perfusion SPECT-CT fusion images and non-breath-hold Technegas SPECT. The severity of perfusion defects with or without MCA was quantified by regions-of-interest analysis. Results: On DIBrH CT and perfusion SPECT, in contrast to no noticeable CT attenuation abnormality and fairly uniform perfusion in controls, 60 MCA and 274 perfusion defects in PVD patients, and 18 MCA and 61 defects in OAD patients were identified, with a total of 77 ventilation defects on Technegas SPECT in all patients. SPECT-CT correlation showed that, throughout the 78 MCA sites of all patients, lung perfusion was persistently decreased at low CT attenuation and preserved at intervening high CT attenuation, while lung ventilation was poorly correlated with CT attenuation change. The radioactivity ratios of reduced perfusion and the intervening preserved perfusion at the 78 perfusion defects with MCA were significantly lower than those at the remaining 257 defects without MCA (P<0.0001). Conclusion: Although further validation is

  1. Functional Mechanism of Lung Mosaic CT Attenuation: Assessment with Deep-Inspiration Breath-Hold Perfusion SPECT-CT Fusion Imaging and Non-Breath-Hold Technegas SPECT

    International Nuclear Information System (INIS)

    Background: The functional mechanism of lung mosaic computed tomography attenuation (MCA) in pulmonary vascular disease (PVD) and obstructive airway disease (OAD) has not yet been fully clarified. Purpose: To clarify the mechanism of MCA in these diseases by assessing the relationship between regional lung function and CT attenuation change at MCA sites with the use of automated deep-inspiratory breath-hold (DIBrH) perfusion single-photon emission computed tomography (SPECT)-CT fusion images and non-breath-hold Technegas SPECT. Material and Methods: Subjects were 42 PVD patients (31 pulmonary thromboembolism, four primary/two secondary pulmonary hypertension, and five Takayasu arteritis), 12 OAD patients (five acute asthma, four obliterative bronchiolitis, and three bronchiectasis), and 12 normal controls, all of whom had MCA on DIBrH CT. The relationship between regional lung function and CT attenuation change at the lung slices with MCA was assessed using DIBrH perfusion SPECT-CT fusion images and non-breath-hold Technegas SPECT. The severity of perfusion defects with or without MCA was quantified by regions-of-interest analysis. Results: On DIBrH CT and perfusion SPECT, in contrast to no noticeable CT attenuation abnormality and fairly uniform perfusion in controls, 60 MCA and 274 perfusion defects in PVD patients, and 18 MCA and 61 defects in OAD patients were identified, with a total of 77 ventilation defects on Technegas SPECT in all patients. SPECT-CT correlation showed that, throughout the 78 MCA sites of all patients, lung perfusion was persistently decreased at low CT attenuation and preserved at intervening high CT attenuation, while lung ventilation was poorly correlated with CT attenuation change. The radioactivity ratios of reduced perfusion and the intervening preserved perfusion at the 78 perfusion defects with MCA were significantly lower than those at the remaining 257 defects without MCA (P<0.0001). Conclusion: Although further validation is

  2. Ecological Risk Assessment of Metals Contamination in the Sediments of Natural Urban Wetlands in Dry Tropical Climate.

    Science.gov (United States)

    Rana, Vivek; Maiti, Subodh Kumar; Jagadevan, Sheeja

    2016-09-01

    The pollution load due to metal contamination in the sediments of urban wetlands (Dhanbad, India) due to illegal release of domestic and industrial wastewater was studied by using various geochemical indices, such as contamination factor (Cf), degree of contamination (Cd), modified degree of contamination (mCd), pollution load index (PLI) and geoaccumulation index (Igeo) for Cu, Co, Cd, Cr and Mn. Cluster analysis (CA) and Principal component analysis (PCA) of metals present in wetland sediments were carried out to assess their origin and relationship with each other. The Cf values for different metals in the wetlands under investigation indicated low to very high level of pollution (Cf ranged between 0.02 and 14.15) with highest Cf (14.15) for Cd. The wetland receiving both domestic and industrial wastewater had the highest values of Cd, mCd and PLI as 17.48, 3.49 and 1.03 respectively. PMID:27424247

  3. Baseline risk assessment of ground water contamination at the uranium mill tailings site near Durango, Colorado. Revision 1

    International Nuclear Information System (INIS)

    For the UMTRA Project site located near Durango, Colorado (the Durango site), the Surface Project cleanup occurred from 1986 to 1991. An evaluation was made to determine whether exposure to ground water contaminated by uranium processing could affect people's health. Exposure could occur from drinking water pumped from a hypothetical well drilled in the contaminated ground water area. In addition, environmental risks may result if plants or animals are exposed to contaminated ground water, or surface water that has mixed with contaminated ground water. This risk assessment report is the first site-specific document prepared for the UMTRA Ground Water Project at the Durango site. The results of this report and further site characterization of the Durango site will be used to determine what is necessary to protect public health and the environment, and to comply with the EPA standards

  4. Baseline risk assessment of ground water contamination at the uranium mill tailings site near Durango, Colorado. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    For the UMTRA Project site located near Durango, Colorado (the Durango site), the Surface Project cleanup occurred from 1986 to 1991. An evaluation was made to determine whether exposure to ground water contaminated by uranium processing could affect people`s health. Exposure could occur from drinking water pumped from a hypothetical well drilled in the contaminated ground water area. In addition, environmental risks may result if plants or animals are exposed to contaminated ground water, or surface water that has mixed with contaminated ground water. This risk assessment report is the first site-specific document prepared for the UMTRA Ground Water Project at the Durango site. The results of this report and further site characterization of the Durango site will be used to determine what is necessary to protect public health and the environment, and to comply with the EPA standards.

  5. CAirTOX, An inter-media transfer model for assessing indirect exposures to hazardous air contaminants

    International Nuclear Information System (INIS)

    Risk assessment is a quantitative evaluation of information on potential health hazards of environmental contaminants and the extent of human exposure to these contaminants. As applied to toxic chemical emissions to air, risk assessment involves four interrelated steps. These are (1) determination of source concentrations or emission characteristics, (2) exposure assessment, (3) toxicity assessment, and (4) risk characterization. These steps can be carried out with assistance from analytical models in order to estimate the potential risk associated with existing and future releases. CAirTOX has been developed as a spreadsheet model to assist in making these types of calculations. CAirTOX follows an approach that has been incorporated into the CalTOX model, which was developed for the California Department of Toxic Substances Control, With CAirTOX, we can address how contaminants released to an air basin can lead to contamination of soil, food, surface water, and sediments. The modeling effort includes a multimedia transport and transformation model, exposure scenario models, and efforts to quantify uncertainty in multimedia, multiple-pathway exposure assessments. The capacity to explicitly address uncertainty has been incorporated into the model in two ways. First, the spreadsheet form of the model makes it compatible with Monte-Carlo add-on programs that are available for uncertainty analysis. Second, all model inputs are specified in terms of an arithmetic mean and coefficient of variation so that uncertainty analyses can be carried out

  6. Identification of contaminants of concern for the postclosure assessment of the concept for the disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    The concept for the disposal of Canada's nuclear fuel waste involves the isolation of irradiated fuel in corrosion-resistant containers emplaced din din a vault located deep in crystalline rock of the Canadian Shield. To estimate potential impacts on members of a critical group far into the future, a postclosure assessment evaluates the long-term safety of the concept. Although the nuclear fuel waste from CANDU (Canada Deuterium Uranium) power generating stations contains several hundreds of potentially toxic radionuclides and chemical elements (referred to as contaminants), many of these would not lead to significant impacts. This report provides an upper bound on estimated radiation dose and chemical toxicity effects on humans from all potentially toxic contaminants, and it identifies those that require detailed consideration in the postclosure assessment. This report also examines the origins and properties of the contaminants. Properties of interest include radioactive half-life, inventory, mobility in groundwaters and sorption on rock, degree of toxicity, and precursors and progeny (or parents and daughters) for members of a decay chain. The report considers how these properties affect the behaviour of different contaminants in different parts of the disposal system. The discussion leads to suggested methods of treatment of different contaminants when simulating their fate within the disposal system. In particular, recommendations are made on how the actinide decay chains can be simplified for study in the postclosure assessment. (author). 56 refs., 22 tabs., 12 figs

  7. Assessment of heavy metal contamination of dust at some selected fuel filling stations in Accra

    International Nuclear Information System (INIS)

    Heavy metal contaminated dust particles of fuel filling stations can be re-suspended into the ambient air and serve as a source of atmospheric pollution since the fine particles are aerodynamic and have longer life time in ambient air. This can cause ill-health effect on the fuel attendants and residents within the neighbourhood especially infants and the aged who are more vulnerable. In spite of this, not much research has been done on heavy metal contamination of dust at fuel filling stations. In this study, 55 dust samples were collected from six fuel filling stations in the Ga-East district and Accra Metropolitan assembly, both in Accra, in order to assess the levels of contamination of heavy metals; their possible sources and the human health risk associated with them. The dust samples were divided into two parts with one part sieved into four fractions using metric mesh sizes 500 µm, 200µm, 100µm and 45 µm, and pulverised. Total concentrations of heavy metals (Si, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Br, Rb, Sr, Y, Zr and Pb) were determined in the dust samples using energy dispersive X-ray fluorescence analysis. The pollution indices; enrichment factors (EF), index of geoaccumulation (Igeo), contamination factor (CF) and pollution load index (PLI) were used to identify possible levels of pollution from anthropogenic sources. The possible sources of metals were also identified with principal component analysis. Noncancer effect of children and adults due to exposure to dust from these fuel filling stations were also estimated. For the three fuelling areas, the average concentrations of V, Cr, Ni and Cu exceeded the acceptable values in common soil in the <45 µm fraction. The average concentration of Zn however exceeded the acceptable value only at the mixed-fuel fuelling area whereas the average concentration of Pb was within the acceptable value for all three fuelling areas. The dust samples showed moderate to significant enrichments for V, Cu, Br

  8. DIADEME: A computer code to assess in operation defective fuel characteristics and primary circuit contamination

    International Nuclear Information System (INIS)

    DIADEME is a computer code developed within the framework of R and D cooperation between the French Atomic Energy Commission (CEA), Electricite de France (EdF) and FRAMATOME-ANP. Its aim is to assess in operation defective fuel characteristics and primary circuit contamination for actinides and long half-life fission products involved in health physics problems as well as in waste and decommissioning studies. DIADEME has been developed and qualified for the EDF nuclear power plants. For many years, both theoretical and experimental studies have been carried out at the CEA on the release of fission products and actinides out of defective fuel rods in operation, their migration and deposition in PWR primary circuits. These studies have allowed defect characteristic diagnosis methods to be developed, based on radiochemical measurements of the primary coolant. These methods are generally used along with gamma spectrometry measurements on primary water sampling. In order to be completely efficient, these methods can also be used in connection with an on-line primary water gamma spectrometry device. This permits to obtain the most comprehensive data on fission product activity evolutions at steady state and during operation transients, and allows the on-line characterization of the defective fuel assemblies. For long half-life fission products and for actinides, DIADEME is also able to assess the activities of soluble and insoluble forms in the primary water and in the chemical and voluminal control system (CVCS) filters and resins, as well as those activities deposited on primary circuit surfaces. (author)

  9. Pathway analysis and exposure assessment: MEPAS modeling for nonradiological chemical contaminants at the Hanford Site

    International Nuclear Information System (INIS)

    A Chemical Pathway Analysis and Exposure Assessment was performed by the Surface Environmental Surveillance Project (SESP). The SESP monitors air, surface water, sediment, agricultural products, vegetation, soil, and wildlife in order to assess onsite of offsite environmental impacts and offsite human health risk at the Hanford Site. The objectives of this study are (1) determine if a nonradiological chemical monitoring program is warranted for the Hanford Site, (2) ensure that the selection of surveillance parameters such as media, sampling location, and analytes are chosen in a manner that is scientifically sound and cost-efficient, and (3) identify specific nonradiological chemicals of concern (COC) for the Hanford Site. The basis for identification of COC for the Hanford Site was an extensive literature review. The model was also used to predict COC concentrations required onsite to achieve an offsite cancer incidence of 1 E-6 and a hazard quotient of 1.0. This study indicated that nonradiological chemical contamination occurring onsite does not pose a significant offsite human health risk. The highest cancer incidence to the offsite maximally exposed individual from COC was from arsenic (1.76E-1 0); the highest hazard quotient was chromium VI (1.48E-04)

  10. Risk assessment of particle dispersion and trace element contamination from mine-waste dumps.

    Science.gov (United States)

    Romero, Antonio; González, Isabel; Martín, José María; Vázquez, María Auxiliadora; Ortiz, Pilar

    2015-04-01

    In this study, a model to delimit risk zones influenced by atmospheric particle dispersion from mine-waste dumps is developed to assess their influence on the soil and the population according to the concentration of trace elements in the waste. The model is applied to the Riotinto Mine (in SW Spain), which has a long history of mining and heavy land contamination. The waste materials are separated into three clusters according to the mapping, mineralogy, and geochemical classification using cluster analysis. Two of the clusters are composed of slag, fresh pyrite, and roasted pyrite ashes, which may contain high concentrations of trace elements (e.g., >1 % As or >4 % Pb). The average pollution load index (PLI) calculated for As, Cd, Co, Cu, Pb, Tl, and Zn versus the baseline of the regional soil is 19. The other cluster is primarily composed of sterile rocks and ochreous tailings, and the average PLI is 3. The combination of particle dispersion calculated by a Gaussian model, the PLI, the surface area of each waste and the wind direction is used to develop a risk-assessment model with Geographic Information System GIS software. The zone of high risk can affect the agricultural soil and the population in the study area, particularly if mining activity is restarted in the near future. This model can be applied to spatial planning and environmental protection if the information is complemented with atmospheric particulate matter studies. PMID:25190539

  11. Formation of secondary hematite and its role in attenuation of contaminants at mine tailings: review and comparison of sites in Zambia and Namibia

    OpenAIRE

    Sracek, Ondra

    2015-01-01

    Mine tailings in African countries Zambia and Namibia have been investigated with an objective to determine the role of secondary hematite in immobilization of contaminants. Two sites, Chambishi and Mindolo, are located in the Copperbelt in Zambia with relatively humid climates and two sites, Berg Aukas and Kombat, are in Namibia, where the climate is semiarid. At the Chambishi site which is about 40 years old, a hardpan composed of hematite and gypsum has formed at a depth of about 60 cm and...

  12. A review of soil cadmium contamination in China including a health risk assessment.

    Science.gov (United States)

    Wang, Lin; Cui, Xiangfen; Cheng, Hongguang; Chen, Fei; Wang, Jiantong; Zhao, Xinyi; Lin, Chunye; Pu, Xiao

    2015-11-01

    Cadmium (Cd) is one of the most serious soil contaminants in China, and it poses an increasing risk to human health as large amounts of Cd are emitted into the environment. However, knowledge about soil Cd concentrations and the human health risks of these concentrations at a national scale is limited. In this study, we conducted a review of 190 articles about soil Cd concentrations during 2001 to 2010. The study involved 146 cities in China, and we quantified the risks to human health according to different regions. The results showed that elevated Cd levels were present compared to the background value of soil in 1990, and the soil Cd concentrations in the Guangxi province exceeded even the class III Soil Environmental Quality standard, which is the limit for the normal growth of plants. The Chinese soil Cd concentrations ranged from 0.003 mg kg(-1) to 9.57 mg kg(-1). The soil Cd concentrations had the following trend: northwest > southwest > south central > east > northeast > north. The sources of soil Cd are mainly from smelting, mining, waste disposal, fertilizer and pesticide application, and vehicle exhaust, etc. but differentiated in various regions. The soil Cd contamination in urban areas was more serious than contamination in the agricultural areas. Currently, there is no significant non-carcinogenic risk in any of the provinces. Regarding the different exposure pathways, the dermal pathway is the primary source of soil Cd exposure, and the risk associated with this pathway is generally hundreds of times higher than the risk for an ingestion pathway. For most of the provinces, the health risk to the urban population was higher than the risk to the rural population. For each population, the carcinogenic risk was less than 10(-6) in most of the provinces, except for the urban population in the Hunan province. If the other exposure pathways are fully considered, then the people in these areas may have a higher carcinogenic risk. This

  13. Genotoxicity changes in test plot soil: Impact on risk assessment at a contaminated site planning bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Collie, S.L.; Donnelly, K.C. [Texas A and M Univ., College Station, TX (United States)

    1995-12-31

    Soil samples from test plots designed to investigate the suitability of biodegradation to reduce levels of polycyclic aromatic hydrocarbons (PAHs) and pentachlorophenol (PCP) were collected and solvent-extracted throughout a four-month study. Samples were followed for contaminant concentration and genotoxicity. Test plots were constructed to represent four concentrations of contaminated soil. Although the highest PCP concentration plot was negative in the Salmonella/microsome plate incorporation both with and without metabolic activation at the beginning of the treatment period, these soils became cytotoxic by the end of the study when tested without metabolic activation, and chemical analysis indicated no degradation of PCP. The methanol extract from the lowest PCP concentration plot was positive in the plate incorporation assay at the beginning of the study with an average weighted activity of 29 revertants/gram soil without and 32 revertants/g with metabolic activation at the highest dose level. The mutagenic potential of the methanol extract of this soil increased to an average weighted activity of 306 revertants/g without and 291 revertants/g with metabolic activation, despite a reduction from 46 to below 10 {micro}g PCP/g soil. A human health risk assessment employing the current US/EPA method of incorporating chemical concentration data in calculating cancer risk was then compared with the level of risk that can be inferred from the corresponding bioassay data. These findings emphasize the need for careful remediation design as this step will prove critical in achieving both maximum biodegradation and protection of human health.

  14. Performance Assessment and Monitoring of a Permeable Reactive Barrier for the Remediation of a Contaminated Site

    Directory of Open Access Journals (Sweden)

    Valerio Zolla

    2007-01-01

    Full Text Available The present study illustrates the long-term monitoring plan carried out in order to investigate the performance of a zero-valent iron permeable reactive barrier (PRB at a chlorinated solvents’ site. The cleanup intervention has been undertaken at an industrial landfill located near the city of Turin (Italy and represents the first full-scale application of this technology in Italy. The monitoring plan started in November 2005 with the aim to verify the attainment of the cleanup goals and to evaluate the efficiency status of the PRB. Controls focuses not only on contaminant monitoring but also on the hydraulic and chemical conditions created by the barrier, in order to evaluate potential long term effects of secondary biogeochemical processes (e.g. mineral precipitation, microbially-mediated redox transformation, gas accumulation on PRB performance. The monitoring plan provides controls on groundwater chemistry (target contaminants and geochemical indicators and core sampling for mineralogical analysis of zero-valent iron by X-ray diffraction and scanning electron microscopy. The first, partial results of the monitoring activity are illustrated. Monitoring data clearly indicate that the plume is being adequately captured and treated in order to accomplish the clean-up goals with a good safety margin. However, it results that mineral precipitation and gas phase accumulation could determine, over time, a decreasing in hydraulic conductivity and porosity of the barrier, thus modifying the flow field through the reactive cell. Besides the monitoring controls, further investigations will be performed to assess the occurring microbial process and to evaluate their impact on PRB performance.

  15. Mercury contamination in human hair and fish from Cambodia: levels, specific accumulation and risk assessment

    International Nuclear Information System (INIS)

    Mercury (Hg) concentrations in human hair and fish samples from Phnom Penh, Kien Svay, Tomnup Rolork and Batrong, Cambodia, collected in November 1999 and December 2000 were determined to understand the status of contamination, and age- and sex-dependent accumulation in humans and to assess the intake of mercury via fish consumption. Mercury concentrations in human hair ranged from 0.54 to 190 μg/g dry wt. About 3% of the samples contained Hg levels exceeding the no observed adverse effects level (NOAEL) of WHO (50 μg/g) and the levels in some hair samples of women also exceeded the NOAEL (10 μg/g) associated with fetus neurotoxicity. A weak but significant positive correlation was observed between age and Hg levels in hair of residents. Mercury concentrations in muscle of marine and freshwater fish from Cambodia ranged from <0.01 to 0.96 μg/g wet wt. Mercury intake rates were estimated on the basis of the Hg content in fish and daily fish consumption. Three samples of marine fish including sharp-tooth snapper and obtuse barracuda, and one sample of sharp-tooth snapper exceeded the guidelines by US EPA and by Joint FAO/WHO Expert Committee on Food Additives (JECFA), respectively, which indicates that some fish specimens examined (9% and 3% for US EPA and JECFA guidelines, respectively) were hazardous for consumption at the ingestion rate of Cambodian people (32.6 g/day). It is suggested that fish is probably the main source of Hg for Cambodian people. However, extremely high Hg concentrations were observed in some individuals and could not be explained by Hg intake from fish consumption, indicating some other contamination sources of Hg in Cambodia. - A source other than fish may be responsible for high Hg in some Cambodians

  16. Chelating impact assessment of biological ad chemical chelates on metal extraction from contaminated soils

    International Nuclear Information System (INIS)

    Soil contamination is the result of uncontrolled waste dumping and poor practices by humans. Of all the pollutants heavy metals are of particular concern due to their atmospheric deposition, leaching capacity and non-biodegradability. Heavy metal containing effluent is discharged into the agricultural fields and water bodies. This results in the accumulation of heavy metals in soil and the crops grown on that soil. Studies have revealed detrimental impacts on soil fertility and the poor health of animals and humans. Phytoextraction is widely researched for remediation of heavy metal contaminated soil. To enhance the effect of phytoextraction heavy metals have to be available to the plants in soluble form. In this study the potential of different chelating agents was assessed in solubilizing the heavy metals making easy for plants to uptake them. For this purpose efficient chemical and biological chelating agent had to be identified. Along with that an optimum dose and application time for chemical chelating agent was determined. Ethylenediamine tetraacetic acid (EDTA), Diethylene triamine pentaacetic acid (DTPA), Nitriloacetic acid (NTA) were applied to the soil, containing Pb, Cr, Cu and Cd, at different concentrations and application time. Aspergillus niger and Aspergillus flavus were incubated in soil for different time periods. In correspondence with findings of the study, Pb and Cr were best solubilized by 5mM EDTA. For Cd and Cu 5mM DTPA carried out efficient chelation. NTA showed relatively inadequate solubilisation, although for Cr it performed equal to EDTA. A. niger and A. flavus instead of solubilizing adsorbed the metals in their biomass. Adsorption was mainly carried out by A. niger. (author)

  17. Metal uptake by homegrown vegetables – The relative importance in human health risk assessments at contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    Augustsson, Anna L.M., E-mail: anna.augustsson@lnu.se [Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar (Sweden); Uddh-Söderberg, Terese E. [Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar (Sweden); Hogmalm, K. Johan [Department of Earth Sciences, University of Gothenburg, Gothenburg (Sweden); Filipsson, Monika E.M. [Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar (Sweden)

    2015-04-15

    Risk assessments of contaminated land often involve the use of generic bioconcentration factors (BCFs), which express contaminant concentrations in edible plant parts as a function of the concentration in soil, in order to assess the risks associated with consumption of homegrown vegetables. This study aimed to quantify variability in BCFs and evaluate the implications of this variability for human exposure assessments, focusing on cadmium (Cd) and lead (Pb) in lettuce and potatoes sampled around 22 contaminated glassworks sites. In addition, risks associated with measured Cd and Pb concentrations in soil and vegetable samples were characterized and a probabilistic exposure assessment was conducted to estimate the likelihood of local residents exceeding tolerable daily intakes. The results show that concentrations in vegetables were only moderately elevated despite high concentrations in soil, and most samples complied with applicable foodstuff legislation. Still, the daily intake of Cd (but not Pb) was assessed to exceed toxicological thresholds for about a fifth of the study population. Bioconcentration factors were found to vary more than indicated by previous studies, but decreasing BCFs with increasing metal concentrations in the soil can explain why the calculated exposure is only moderately affected by the choice of BCF value when generic soil guideline values are exceeded and the risk may be unacceptable. - Highlights: • Uptake of Cd and Pb by lettuce and potatoes increased with soil contamination. • Consumption of homegrown vegetables may lead to a daily Cd intake above TDIs. • The variability in the calculated BCFs is high when compared to previous studies. • Exposure assessments are most sensitive to the choice of BCFs at low contamination.

  18. Metal uptake by homegrown vegetables – The relative importance in human health risk assessments at contaminated sites

    International Nuclear Information System (INIS)

    Risk assessments of contaminated land often involve the use of generic bioconcentration factors (BCFs), which express contaminant concentrations in edible plant parts as a function of the concentration in soil, in order to assess the risks associated with consumption of homegrown vegetables. This study aimed to quantify variability in BCFs and evaluate the implications of this variability for human exposure assessments, focusing on cadmium (Cd) and lead (Pb) in lettuce and potatoes sampled around 22 contaminated glassworks sites. In addition, risks associated with measured Cd and Pb concentrations in soil and vegetable samples were characterized and a probabilistic exposure assessment was conducted to estimate the likelihood of local residents exceeding tolerable daily intakes. The results show that concentrations in vegetables were only moderately elevated despite high concentrations in soil, and most samples complied with applicable foodstuff legislation. Still, the daily intake of Cd (but not Pb) was assessed to exceed toxicological thresholds for about a fifth of the study population. Bioconcentration factors were found to vary more than indicated by previous studies, but decreasing BCFs with increasing metal concentrations in the soil can explain why the calculated exposure is only moderately affected by the choice of BCF value when generic soil guideline values are exceeded and the risk may be unacceptable. - Highlights: • Uptake of Cd and Pb by lettuce and potatoes increased with soil contamination. • Consumption of homegrown vegetables may lead to a daily Cd intake above TDIs. • The variability in the calculated BCFs is high when compared to previous studies. • Exposure assessments are most sensitive to the choice of BCFs at low contamination

  19. COMPARATIVE ANALYSIS OF APPROACHES TO ECOLOGICAL ASSESSMENT OF POLYELEMENT CONTAMINATION SOIL OF URBAN ECOSYSTEM BY HEAVY METALS

    Directory of Open Access Journals (Sweden)

    YAKOVYSHYNA T. F.

    2016-06-01

    Full Text Available Raising of problem. In modern conditions, anthropogenic impact to the soil urban ecosystems is fairly stable over time and space, is manifested in various forms, as the transformation of the soil profile, the change in direction of the soil-forming processes, contamination of the various pollutants, and, above all, heavy metals (HM – elements of the first class of the danger. Their sources of the income to the urban environment are industrial enterprises, transport, housing and communal services. Determination of the anthropogenic pressure to the urban soil is carried out by the environmental assessment of the HM polyelement contamination, which allows to establish not only the fact of pollution, but also limits of the possible load with considering regional background or sanitary standards – MPC. However, until now discussions arise regarding the index which will be carried out the valuation – the cornerstone of any methodological approach to the environmental assessment of the soil polyelement contamination by the HM of the urban ecosystems, which allows to establish not only the fact of contamination, but also limits the possible load, taking into account the regional background or sanitary norm – MPC. Purpose. Lies in the grounded selection of the environmental assessment indexes of the soil contamination by the HM of the urban ecosystems through a comparative analysis of the existing approaches, such as the determination of the summary contamination index (SCI, the index of the soil contamination (ISC, factor imbalance (Sd, taking into account environmental safety standards and binding to the specific conditions territory. Conclusion. In summary it should be noted that it is necessary to use a set of integrated indexes, including the SCI to determine the violation of the metals content with respect to the geochemical background of zonal soil, ISC – link the contamination level with health indexes of the environmental safety

  20. Risk assessment through drinking water pathway via uncertainty modeling of contaminant transport using soft computing

    International Nuclear Information System (INIS)

    The basic objective of an environmental impact assessment (EIA) is to build guidelines to reduce the associated risk or mitigate the consequences of the reactor accident at its source to prevent deterministic health effects, to reduce the risk of stochastic health effects (eg. cancer and severe hereditary effects) as much as reasonable achievable by implementing protective actions in accordance with IAEA guidance (IAEA Safety Series No. 115, 1996). The measure of exposure being the basic tool to take any appropriate decisions related to risk reduction, EIA is traditionally expressed in terms of radiation exposure to the member of the public. However, models used to estimate the exposure received by the member of the public are governed by parameters some of which are deterministic with relative uncertainty and some of which are stochastic as well as imprecise (insufficient knowledge). In an admixture environment of this type, it is essential to assess the uncertainty of a model to estimate the bounds of the exposure to the public to invoke a decision during an event of nuclear or radiological emergency. With a view to this soft computing technique such as evidence theory based assessment of model parameters is addressed to compute the risk or exposure to the member of the public. The possible pathway of exposure to the member of the public in the aquatic food stream is the drinking of water. Accordingly, this paper presents the uncertainty analysis of exposure via uncertainty analysis of the contaminated water. Evidence theory finally addresses the uncertainty in terms of lower bound as belief measure and upper bound of exposure as plausibility measure. In this work EIA is presented using evidence theory. Data fusion technique is used to aggregate the knowledge on the uncertain information. Uncertainty of concentration and exposure is expressed as an interval of belief, plausibility

  1. Environmental assessment on electrokinetic remediation of multimetal-contaminated site: a case study.

    Science.gov (United States)

    Kim, Do-Hyung; Yoo, Jong-Chan; Hwang, Bo-Ram; Yang, Jung-Seok; Baek, Kitae

    2014-05-01

    In this study, an environmental assessment on an electrokinetic (EK) system for the remediation of a multimetal-contaminated real site was conducted using a green and sustainable remediation (GSR) tool. The entire EK process was classified into major four phases consisting of remedial investigations (RIs), remedial action construction (RAC), remedial action operation (RAO), and long-term monitoring (LTM) for environmental assessment. The environmental footprints, including greenhouse gas (GHG) emissions, total energy used, air emissions of criteria pollutants, such as NOx, SOx, and PM10, and water consumption, were calculated, and the relative contribution in each phase was analyzed in the environmental assessment. In the RAC phase, the relative contribution of the GHG emissions, total energy used, and PM10 emissions were 77.3, 67.6, and 70.4%, respectively, which were higher than those of the other phases because the material consumption and equipment used for system construction were high. In the RAO phase, the relative contributions of water consumption and NOx and SOx emissions were 94.7, 85.2, and 91.0%, respectively, which were higher than those of the other phases, because the water and electricity consumption required for system operation was high. In the RIs and LTM phases, the environmental footprints were negligible because the material and energy consumption was less. In conclusion, the consumable materials and electrical energy consumption might be very important for GSR in the EK remediation process, because the production of consumable materials and electrical energy consumption highly affects the GHG emissions, total energy used, and air emissions such as NOx and SOx. PMID:24515871

  2. Impact of CT based attenuation correction on quantitative assessment of DaTSCAN (123I-Ioflupane) imaging in diagnosis of extrapyramidal diseases

    International Nuclear Information System (INIS)

    The quality of visually and semi-quantitatively assessed DaTSCAN images is crucial for differential diagnostics of extrapyramidal diseases. Neuroimaging with the use of presynaptic tracers of the dopaminergic system provides evidence of nigrostriatal degeneration and may support the clinical diagnosis of Parkinsonism. During the last two years (2007-2008) we tried to elaborate the optimal methodology of SPECT/CT examination with the use of DaTSCAN (123I-Ioflupane), and we sought to evaluate the effect of the reconstruction and attenuation correction method on semi-quantitative measures of relative uptake in the striatum. In a present study, we retrospectively studied DaTSCAN scans of 44 consecutive patients with clinical indications of Parkinson's disease or uncertain Parkinsonian syndromes. The quality of DaTSCAN images reconstructed with the use of ordered-subset expectation maximization reconstruction technique (OSEM) with attenuation correction based on CT maps was found to be superior to that provided by the commonly applied filtered backprojection method (FBP) with Chang attenuation correction. OSEM reconstructed transverse slices were more legible for clinical interpretation because of increased contrast and improved delineation between striatum structures. Semiquantitative assessments of relative striatum uptake for OSEM reconstructed slices secured better intraperator reproducibility than that obtained by FBP method. (authors)

  3. Can Physiological Endpoints Improve the Sensitivity of Assays with Plants in the Risk Assessment of Contaminated Soils?

    OpenAIRE

    Ana Gavina; Antunes, Sara C.; Glória Pinto; Maria Teresa Claro; Conceição Santos; Fernando Gonçalves; Ruth Pereira

    2013-01-01

    Site-specific risk assessment of contaminated areas indicates prior areas for intervention, and provides helpful information for risk managers. This study was conducted in the Ervedosa mine area (Bragança, Portugal), where both underground and open pit exploration of tin and arsenic minerals were performed for about one century (1857 – 1969). We aimed at obtaining ecotoxicological information with terrestrial and aquatic plant species to integrate in the risk assessment of this mine area. Fur...

  4. Model assessment of additional contamination of water bodies as a result of wildfires in the Chernobyl exclusion zone

    International Nuclear Information System (INIS)

    Forest fires and wild fires are recognized as a possible cause of resuspension and redistribution of radioactive substances when occurring on lands contaminated with such materials, and as such are a matter of concern within the regions of Belarus and the Ukraine which were contaminated by the Chernobyl accident in 1986. Modelling the effects of such fires on radioactive contaminants is a complex matter given the number of variables involved. In this paper, a probabilistic model was developed using empirical data drawn from the Polessie State Radiation-Ecological Reserve (PSRER), Belarus, and the Maximum Entropy Method. Using the model, it was possible to derive estimates of the contribution of fire events to overall variability in the levels of 137Cs and 239,240Pu in ground air as well as estimates of the deposition of these radionuclides to specific water bodies within the contaminated areas of Belarus. Results indicate that fire events are potentially significant redistributors of radioactive contaminants within the study area and may result in additional contamination being introduced to water bodies. - Highlights: • The role of fire in redistribution of radionuclides was assessed. • Transfer of radionuclides to water bodies due to fire was estimated. • A maximum entropy method was used for modelling. • Results indicate potential for significant transfer of radionuclides

  5. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Green River, Utah. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    The Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (phase 1) and the Ground Water Project (phase 2). For the UMTRA Project site located near Green River, Utah, the Surface Project cleanup occurred from 1988 to 1989. The tailings and radioactively contaminated soils and materials were removed from their original locations and placed into a disposal cell on the site. The disposal cell is designed to minimize radiation emissions and minimize further contamination of ground water beneath the site. The UMTRA Project`s second phase, the Ground Water Project, evaluates the nature and extent of ground water contamination resulting from uranium processing and determines a strategy for ground water compliance with the Environmental Protection Agency (EPA) ground water standards established for the UMTRA Project. For the Green River site, the risk assessment helps determine whether human health risks result from exposure to ground water contaminated by uranium processing. This risk assessment report is the first site-specific document prepared for the UMTRA Ground Water Project at the Green River site. What follows is an evaluation of current and possible future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will be used to determine what is necessary, if anything, to protect human health and the environment while complying with EPA standards.

  6. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Green River, Utah. Revision 1

    International Nuclear Information System (INIS)

    The Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (phase 1) and the Ground Water Project (phase 2). For the UMTRA Project site located near Green River, Utah, the Surface Project cleanup occurred from 1988 to 1989. The tailings and radioactively contaminated soils and materials were removed from their original locations and placed into a disposal cell on the site. The disposal cell is designed to minimize radiation emissions and minimize further contamination of ground water beneath the site. The UMTRA Project's second phase, the Ground Water Project, evaluates the nature and extent of ground water contamination resulting from uranium processing and determines a strategy for ground water compliance with the Environmental Protection Agency (EPA) ground water standards established for the UMTRA Project. For the Green River site, the risk assessment helps determine whether human health risks result from exposure to ground water contaminated by uranium processing. This risk assessment report is the first site-specific document prepared for the UMTRA Ground Water Project at the Green River site. What follows is an evaluation of current and possible future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will be used to determine what is necessary, if anything, to protect human health and the environment while complying with EPA standards

  7. Environmental impact assessment of biofuel production on contaminated land - Swedish case studies

    Energy Technology Data Exchange (ETDEWEB)

    Andersson-Skoeld, Yvonne; Suer, Pascal (Swedish Geotechnical Institute, Linkoeping (Sweden)); Blom, Sonja (FB Engineering AB, Goeteborg (Sweden)); Bardos, Paul (r3 Environmental Technology Ltd, Reading (United Kingdom)); Track, Thomas; Polland, Marcel (DECHEMA e. V., Frankfurt am Main (Germany))

    2009-07-01

    This report studies the (possible) cultivation of short rotation wood (Salix Vinimalis) on two contaminated sites from an environmental perspective, through a life cycle analysis (LCA) and carbon footprint, with an outlook towards an overarching method for a qualitative or semi-quantitative analysis based on a life cycle framework. Two areas were selected as case studies: a small site where short rotation crop (Salix Vinimalis) cultivation is in progress and a large site where biofuel production is hypothetical. For the selection of suitable sites, the following aspects were considered: Site location and size, so that biofuel cultivation might be economically viable without a remediation bonus, Topography and soil conditions, so that machinery could be used for cultivation, Time, so that the site was not in urgent need of remediation due to environmental or human health risks, or acute exploitation requirements, Contamination degree, which should not be plant-toxic, Contamination depth, Assessment of optimum crop and its use. For doubtful areas, it is especially important to analyse what the most viable option for the contaminated site is, and what bio-product could be used. For a more comprehensive analysis, which also incorporates local economic and social aspects, the decision support matrix, inter alia, described in the main report of the project Rejuvenate, is recommended. The calculation of emissions for the LCA and the carbon footprint used a German software tool for LCA of soil remediation. The software includes equipment emission data published in 1995. The module 'landfarming' has been used in this study to calculate emissions from herbicide application, fertilisation, ploughing and deep-ploughing, Salix harvest, harrowing etc. Since production of herbicide and Salix Vinimalis shoots were not included in the software, they were not included in the study. The conclusions for the two sites were very similar, in spite of the large differences

  8. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Naturita, Colorado. Revision 1

    International Nuclear Information System (INIS)

    The Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project, and the Ground Water Project. For the UMTRA Project site located near Naturita, Colorado, phase I involves the removal of radioactively contaminated soils and materials and their transportation to a disposal site at Union Carbide Corporation's Upper Burbank Repository at Uravan, Colorado. The surface cleanup will reduce radon and other radiation emissions from the former uranium processing site and prevent further site-related contamination of ground water. Phase II of the project will evaluate the nature and extent of ground water contamination resulting from uranium processing and its effect on human health and the environment, and will determine site-specific ground water compliance strategies in accordance with the US Environmental Protection Agency (EPA) ground water standards established for the UMTRA Project. Human health risks could occur from drinking water pumped from a hypothetical well drilled in the contaminated ground water area. Environmental risks may result if plants or animals are exposed to contaminated ground water or surface water that has mixed with contaminated ground water. Therefore, a risk assessment was conducted for the Naturita site. This risk assessment report is the first site-specific document prepared for the Ground Water Project at the Naturita site. What follows is an evaluation of current and possible future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will be used to determine whether any action is needed to protect human health or the environment

  9. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Naturita, Colorado. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    The Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project, and the Ground Water Project. For the UMTRA Project site located near Naturita, Colorado, phase I involves the removal of radioactively contaminated soils and materials and their transportation to a disposal site at Union Carbide Corporation`s Upper Burbank Repository at Uravan, Colorado. The surface cleanup will reduce radon and other radiation emissions from the former uranium processing site and prevent further site-related contamination of ground water. Phase II of the project will evaluate the nature and extent of ground water contamination resulting from uranium processing and its effect on human health and the environment, and will determine site-specific ground water compliance strategies in accordance with the US Environmental Protection Agency (EPA) ground water standards established for the UMTRA Project. Human health risks could occur from drinking water pumped from a hypothetical well drilled in the contaminated ground water area. Environmental risks may result if plants or animals are exposed to contaminated ground water or surface water that has mixed with contaminated ground water. Therefore, a risk assessment was conducted for the Naturita site. This risk assessment report is the first site-specific document prepared for the Ground Water Project at the Naturita site. What follows is an evaluation of current and possible future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will be used to determine whether any action is needed to protect human health or the environment.

  10. Modeling aeolian transport in response to succession, disturbance and future climate: Dynamic long-term risk assessment for contaminant redistribution

    Science.gov (United States)

    Breshears, D.D.; Kirchner, T.B.; Whicker, J.J.; Field, J.P.; Allen, C.D.

    2012-01-01

    Aeolian sediment transport is a fundamental process redistributing sediment, nutrients, and contaminants in dryland ecosystems. Over time frames of centuries or longer, horizontal sediment fluxes and associated rates of contaminant transport are likely to be influenced by succession, disturbances, and changes in climate, yet models of horizontal sediment transport that account for these fundamental factors are lacking, precluding in large part accurate assessment of human health risks associated with persistent soil-bound contaminants. We present a simple model based on empirical measurements of horizontal sediment transport (predominantly saltation) to predict potential contaminant transport rates for recently disturbed sites such as a landfill cover. Omnidirectional transport is estimated within vegetation that changes using a simple Markov model that simulates successional trajectory and considers three types of short-term disturbances (surface fire, crown fire, and drought-induced plant mortality) under current and projected climates. The model results highlight that movement of contaminated soil is sensitive to vegetation dynamics and increases substantially (e.g., > fivefold) when disturbance and/or future climate are considered. The time-dependent responses in horizontal sediment fluxes and associated contaminant fluxes were sensitive to variability in the timing of disturbance, with longer intervals between disturbance allowing woody plants to become dominant and crown fire and drought abruptly reducing woody plant cover. Our results, which have direct implications for contaminant transport and landfill management in the specific context of our assessment, also have general relevance because they highlight the need to more fully account for vegetation dynamics, disturbance, and changing climate in aeolian process studies. ?? 2011.

  11. A simple and inexpensive technique for assessing microbial contamination during drilling operations

    Science.gov (United States)

    Friese, André; Vuillemin, Aurèle; Kallmeyer, Jens; Wagner, Dirk

    2016-04-01

    , the core was cut and the liner fluid collected. From each whole round core (WRC) that was taken for microbiological and biogeochemical analyses, small samples of 1 cc were retrieved with sterile cutoff syringes from the rim, the center and an intermediate position. After dilution and homogenization in 9 mL MilliQ water, 10 μL of the sediment slurry was transferred onto a filter membrane and particles counted via fluorescence microscopy. Additionally, particles in the liner fluid were also quantified. This allows the quantification of the amount of drilling fluid that has entered the sediment sample during drilling. The minimum detectable volume of drilling fluid was in the order of single nanoliters per cc of sediment, which is in the range of established techniques. The presented method requires only a minimum of equipment and allows rapid determination of contamination in the sediment core and an easy to handle on-site analysis at low costs. The sensitivity is in the same range as perfluorocarbon and microsphere tracer applications. Thus, it offers an inexpensive but powerful technique for contamination assessment for future drilling campaigns.

  12. Assessment of the genotoxic potential of contaminated estuarine sediments in fish peripheral blood: Laboratory versus in situ studies

    International Nuclear Information System (INIS)

    Juvenile Senegalese soles (Solea senegalensis) were exposed to estuarine sediments through 28-day laboratory and in situ (field) bioassays. The sediments, collected from three distinct sites (a reference plus two contaminated) of the Sado Estuary (W Portugal) were characterized for total organic matter, redox potential, fine fraction and for the levels of metals, polycyclic aromatic hydrocarbons (PAHs) and organochlorines, namely polychlorinated biphenyls (PCBs) and dichloro diphenyl tricholoethane plus its main metabolites (DDTs). Genotoxicity was determined in whole peripheral blood by the single-cell gel electrophoresis (SCGE or 'comet') assay and by scoring erythrocytic nuclear abnormalities (ENA). Analysis was complemented with the determination of lipid peroxidation in blood plasma by the thiobarbituric acid reactive substances (TBARS) protocol and cell type sorting. The results showed that exposure to contaminated sediments induced DNA fragmentation and clastogenesis. Still, laboratory exposure to the most contaminated sediment revealed a possible antagonistic effect between metallic and organic contaminants that might have been enhanced by increased bioavailability. The laboratory assay caused a more pronounced increase in ENA whereas a very significant increase in DNA fragmentation was observed in field-tested fish exposed to the reference sediment, which is likely linked to increased lipid peroxidation that probably occurred due to impaired access to food. Influence of natural pathogens was ruled out by unaltered leukocyte counts. The statistical integration of data correlated lipid peroxidation with biological variables such as fish length and weight, whereas the genotoxicity biomarkers were more correlated to sediment contamination. It was demonstrated that laboratory and field bioassays for the risk assessment of sediment contamination may yield different genotoxicity profiles although both provided results that are in overall accordance with sediment

  13. Long-term safety assessment for the disposal of radioactive and non-radioactive contaminants found in common low level radioactive waste streams

    International Nuclear Information System (INIS)

    Low level radioactive waste (LLW) can contain non-radioactive as well as radioactive contaminants. However, very few long-term safety assessments of LLW disposal have included quantitative evaluation of the environmental impacts of the non-radioactive contaminants in the wastes since it is commonly assumed that their impacts will be small compared with those of the radioactive contaminants. To test this assumption, QuantiSci Limited has undertaken two studies for the European Commission. The first study investigated the application of safety assessment approaches developed for radioactive contaminants to the assessment of non-radioactive contaminants in LLW. It demonstrated how disposal limits could be derived for a range of non-radioactive contaminants and generic disposal facilities. Generic, acceptable disposal levels were calculated for a variety of nonradioactive contaminants that would allow the presence of the waste streams in the range of disposal facilities considered. The second study used the same approach but undertook more detailed, disposal system specific calculations, assessing the impacts of both the non-radioactive and radioactive contaminants. The more detailed system and waste stream specific calculations generally implied less restrictive disposal limits for the non-radioactive contaminants. The calculations also indicated that it is prudent to consider non-radioactive as well as radioactive contaminants when assessing the impacts of LLW disposal. (author)

  14. A critical assessment of asphalt batching as a viable remedial option for hydrocarbon contaminated soils

    International Nuclear Information System (INIS)

    Hot mix asphalt production equipment has been successfully utilized in the remediation of soils contaminated with petroleum hydrocarbons. This paper reports that there are two major ways in which this equipment can be used to remediate the petroleum contaminated soils; by incorporating the contaminated soil in the hot mix asphalt product or by using the equipment to clean the soil thermally of the contaminant, leaving a clean soil material. Both of these processes have limitations encompassing technical, political, and certainly liability problems. The remediation of contaminated soil in hot mix asphalt facilities is primarily a physical phenomenon relying on laws of heat and mass transfer. Although chemical changes do occur, the primary function of the process is to cause a physical separation of the contaminant from the soils

  15. Assessing the Risk of Secondary Transfer Via Fingerprint Brush Contamination Using Enhanced Sensitivity DNA Analysis Methods.

    Science.gov (United States)

    Bolivar, Paula-Andrea; Tracey, Martin; McCord, Bruce

    2016-01-01

    Experiments were performed to determine the extent of cross-contamination of DNA resulting from secondary transfer due to fingerprint brushes used on multiple items of evidence. Analysis of both standard and low copy number (LCN) STR was performed. Two different procedures were used to enhance sensitivity, post-PCR cleanup and increased cycle number. Under standard STR typing procedures, some additional alleles were produced that were not present in the controls or blanks; however, there was insufficient data to include the contaminant donor as a contributor. Inclusion of the contaminant donor did occur for one sample using post-PCR cleanup. Detection of the contaminant donor occurred for every replicate of the 31 cycle amplifications; however, using LCN interpretation recommendations for consensus profiles, only one sample would include the contaminant donor. Our results indicate that detection of secondary transfer of DNA can occur through fingerprint brush contamination and is enhanced using LCN-DNA methods. PMID:26300550

  16. Assessment of potential risk of environmental radioactive contamination in northern Europe from terrestrial nuclear units in north-west Russia

    International Nuclear Information System (INIS)

    This Technical Report, being part of the INTAS project 96-1802, constitutes a comprehensive presentation - covering basic results from separate contributions as specified below - of work performed during the first period (February 1998- February 1999). The aim of the INTAS project 96-1802: 'Assessment of potential risk of environmental radioactive contamination in northern Europe from terrestrial nuclear units in north-west Russia' is to assess the potential risk of environmental radioactive contamination from nuclear units in north-west Russia and resulting impacts on population and terrestrial ecosystems in the north. The work focuses mainly on airborne radioactive contamination, but some case studies also deal with accidental leakage from terrestrial nuclear sites to soil and coastal waters. The present material comprises in more detail the contributions from participants no.4 and no.5 based on the four internal reports referred to below: (1) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in north-west Russia: 'Determination of the list of typical sources of danger emergency radioactive releases in an environment in connection with military activity in the North of Russia.' Technical report no.1 of the team no.5. St.-Petersburg State Technical University, St.-Petersburg. July 1998. 43 p.; (2) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in North-west Russia: 'Analysis and description of source-term characteristics for accident linked with airborne radioactive releases from Kola Nuclear Power Plant. Establishing a network facility at INEP for communication among the INTAS Project participants.' Technical report no.1 of the team no.4. Kola Science Centre, Apatity. August 1998. 56 p.; (3) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in

  17. Assessment of potential risk of environmental radioactive contamination in northern Europe from terrestrial nuclear units in north-west Russia

    Energy Technology Data Exchange (ETDEWEB)

    Lisovsky, I. [St. Petersburg State Technical Univ. (Russian Federation); Baklanov, A. [Inst. of the Northern Ecology Problems (INEP) (Russian Federation); Jacovlev, V. [St. Petersburg State Technical Univ. (Russian Federation); Prutskov, V. [Ministry of Defence (Russian Federation). First Central Research Inst. of Naval Shipbuilding; Tarasov, I. [Ministry of Defence (Russian Federation). 23 State Marine Project Inst.; Blecher, A. [State Unitary Enterprise (Russian Federation). Research Inst. of Industrial and Marine Medicine; Zvonariev, B.; Kuchin, N.; Rubanov, S.; Sergeiev, I. [State Scientific Centre (Russian Federation). Central Research Inst. of A. Krylov; Morozov, S.; Koshkin, V.; Fedorenko, Yu.; Rigina, O. [Inst. of the Northern Ecology Problems (INEP) (Russian Federation); Bergman, R. [ed.] [Defence Research Establishment, Umeaa (Sweden). Div. of NBC Defence

    1999-05-01

    This Technical Report, being part of the INTAS project 96-1802, constitutes a comprehensive presentation - covering basic results from separate contributions as specified below - of work performed during the first period (February 1998- February 1999). The aim of the INTAS project 96-1802: `Assessment of potential risk of environmental radioactive contamination in northern Europe from terrestrial nuclear units in north-west Russia` is to assess the potential risk of environmental radioactive contamination from nuclear units in north-west Russia and resulting impacts on population and terrestrial ecosystems in the north. The work focuses mainly on airborne radioactive contamination, but some case studies also deal with accidental leakage from terrestrial nuclear sites to soil and coastal waters. The present material comprises in more detail the contributions from participants no.4 and no.5 based on the four internal reports referred to below: (1) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in north-west Russia: `Determination of the list of typical sources of danger emergency radioactive releases in an environment in connection with military activity in the North of Russia.` Technical report no.1 of the team no.5. St.-Petersburg State Technical University, St.-Petersburg. July 1998. 43 p.; (2) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in North-west Russia: `Analysis and description of source-term characteristics for accident linked with airborne radioactive releases from Kola Nuclear Power Plant. Establishing a network facility at INEP for communication among the INTAS Project participants.` Technical report no.1 of the team no.4. Kola Science Centre, Apatity. August 1998. 56 p.; (3) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in

  18. Multi-contrast attenuation map synthesis for PET/MR scanners: assessment on FDG and Florbetapir PET tracers

    Energy Technology Data Exchange (ETDEWEB)

    Burgos, Ninon [University College London, Translational Imaging Group, Centre for Medical Image Computing, London (United Kingdom); Cardoso, M.J.; Modat, Marc; Ourselin, Sebastien [University College London, Translational Imaging Group, Centre for Medical Image Computing, London (United Kingdom); University College London, Dementia Research Centre, Institute of Neurology, London (United Kingdom); Thielemans, Kris; Dickson, John [University College London, Institute of Nuclear Medicine, London (United Kingdom); Schott, Jonathan M. [University College London, Dementia Research Centre, Institute of Neurology, London (United Kingdom); Atkinson, David [University College London, Centre for Medical Imaging, London (United Kingdom); Arridge, Simon R. [University College London, Centre for Medical Image Computing, London (United Kingdom); Hutton, Brian F. [University College London, Institute of Nuclear Medicine, London (United Kingdom); University of Wollongong, Centre for Medical Radiation Physics, Wollongong, NSW (Australia)

    2015-08-15

    Positron Emission Tomography/Magnetic Resonance Imaging (PET/MR) scanners are expected to offer a new range of clinical applications. Attenuation correction is an essential requirement for quantification of PET data but MRI images do not directly provide a patient-specific attenuation map. Methods We further validate and extend a Computed Tomography (CT) and attenuation map (μ-map) synthesis method based on pre-acquired MRI-CT image pairs. The validation consists of comparing the CT images synthesised with the proposed method to the original CT images. PET images were acquired using two different tracers ({sup 18}F-FDG and {sup 18}F-florbetapir). They were then reconstructed and corrected for attenuation using the synthetic μ-maps and compared to the reference PET images corrected with the CT-based μ-maps. During the validation, we observed that the CT synthesis was inaccurate in areas such as the neck and the cerebellum, and propose a refinement to mitigate these problems, as well as an extension of the method to multi-contrast MRI data. Results With the improvements proposed, a significant enhancement in CT synthesis, which results in a reduced absolute error and a decrease in the bias when reconstructing PET images, was observed. For both tracers, on average, the absolute difference between the reference PET images and the PET images corrected with the proposed method was less than 2%, with a bias inferior to 1%. Conclusion With the proposed method, attenuation information can be accurately derived from MRI images by synthesising CT using routine anatomical sequences. MRI sequences, or combination of sequences, can be used to synthesise CT images, as long as they provide sufficient anatomical information. (orig.)

  19. Multi-contrast attenuation map synthesis for PET/MR scanners: assessment on FDG and Florbetapir PET tracers

    International Nuclear Information System (INIS)

    Positron Emission Tomograp