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Sample records for groundwater soil washing

  1. Soil washing treatability study

    Energy Technology Data Exchange (ETDEWEB)

    Krstich, M.

    1995-12-01

    Soil washing was identified as a viable treatment process option for remediating soil at the FEMP Environmental Management Project (FEMP). Little information relative to the specific application and potential effectiveness of the soil washing process exists that applies to the types of soil at the FEMP. To properly evaluate this process option in conjunction with the ongoing FEMP Remedial Investigation/Feasibility Study (RI/FS), a treatability testing program was necessary to provide a foundation for a detailed technical evaluation of the viability of the process. In August 1991, efforts were initiated to develop a work plan and experimental design for investigating the effectiveness of soil washing on FEMP soil. In August 1992, the final Treatability Study Work Plan for Operable Unit 5: Soil Washing (DOE 1992) was issued. This document shall be referenced throughout the remainder of this report as the Treatability Study Work Plan (TSWP). The purpose of this treatability study was to generate data to support initial screening and the detailed analysis of alternatives for the Operable Unit 5 FS.

  2. SOIL-WASHING TECHNOLOGY AND PRACTICE

    Science.gov (United States)

    Soil washing in the United States has been studied and evaluated with increasing thoroughness during the last 15 to 20 years. It is now entering a phase of actual use and acceptance as its applicability and economics become clearer. This paper reviews the principles behind soil...

  3. SOIL-WASHING TECHNOLOGY AND PRACTICE

    Science.gov (United States)

    Soil washing in the United States has been studied and evaluated with increasing thoroughness during the last 15 to 20 years. It is now entering a phase of actual use and acceptance as its applicability and economics become clearer. This paper reviews the principles behind soil...

  4. Effect of different soil washing solutions on bioavailability of residual arsenic in soils and soil properties.

    Science.gov (United States)

    Im, Jinwoo; Yang, Kyung; Jho, Eun Hea; Nam, Kyoungphile

    2015-11-01

    The effect of soil washing used for arsenic (As)-contaminated soil remediation on soil properties and bioavailability of residual As in soil is receiving increasing attention due to increasing interest in conserving soil qualities after remediation. This study investigates the effect of different washing solutions on bioavailability of residual As in soils and soil properties after soil washing. Regardless of washing solutions, the sequential extraction revealed that the residual As concentrations and the amount of readily labile As in soils were reduced after soil washing. However, the bioassay tests showed that the washed soils exhibited ecotoxicological effects - lower seed germination, shoot growth, and enzyme activities - and this could largely be attributed to the acidic pH and/or excessive nutrient contents of the washed soils depending on washing solutions. Overall, this study showed that treated soils having lower levels of contaminants could still exhibit toxic effects due to changes in soil properties, which highly depended on washing solutions. This study also emphasizes that data on the As concentrations, the soil properties, and the ecotoxicological effects are necessary to properly manage the washed soils for reuses. The results of this study can, thus, be utilized to select proper post-treatment techniques for the washed soils. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Evaluation of soil washing for radiologically contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Gombert, D. II

    1994-03-01

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

  6. Use of green washing fluids in a washing process for dioxin contaminated soils

    Directory of Open Access Journals (Sweden)

    Siwalee Yotapukdee

    2017-09-01

    Full Text Available High levels of dioxin contamination in soil have significant environmental challenges. Soil washing is a successful remediation process that is primarily used to treat coarse soils. Several literature studies have used various kinds of chemical washing liquids to remove dioxins from soils, though there are secondary environmental effects. This study intends to develop environmentally friendly soil washing methods that are effective in dioxin removal at an acceptable cost. Sugarcane wine, compost leachate, and ground fish broth were chosen as potential washing liquids. Each washing liquid was analyzed to determine its content of semivolatile organic compounds (SVOCs and volatile organic compounds (VOCs. These compounds are related to their bio-surfactant content. Several of the identified compounds had properties to help remove dioxins from contaminated soil. In the experiments, high removal efficiencies were observed, up to 70%~95% after five to six washes. Although effective removal was observed, a significant amount of wastewater was produced and the problems were not completely resolved. Thus, the optimal washing conditions are necessary to minimize the overall costs, while improving the process effectiveness. Moreover, an appropriate treatment method is required for wastewater containing dioxins.

  7. Chelant soil-washing technology for metal-contaminated soil.

    Science.gov (United States)

    Voglar, David; Lestan, Domen

    2014-01-01

    We demonstrate here, in a pilot-scale experiment, the feasibility of ethylenediaminetetraacetate (EDTA)based washing technology for soils contaminated with potentially toxic metals. Acid precipitation coupled to initial alkaline toxic metal removal and an electrochemical advanced oxidation process were used for average recovery of 76 +/- 2% of EDTA per batch and total recycle of water in a closed process loop. No waste water was generated; solid wastes were efficiently bitumen-stabilized before disposal. The technology embodiment, using conventional process equipment, such as a mixer for soil extraction, screen for soil/gravel separation, filter chamber presses for soil/liquid and recycled EDTA separation and soil rinsing, continuous centrifuge separator for removal of precipitated metals and electrolytic cells for process water cleansing, removed up to 72%, 25% and 66% of Pb, Zn and Cd from garden soil contaminated with up to 6960, 3797 and 32.6 mg kg(-1) of Pb, Zn and Cd, respectively, in nine 60kg soil batches. Concentrations of Pb and Zn remaining in the remediated soil and bioaccessible from the simulated human intestinal phase soil were reduced by 97% and 96% and were brought under the level of determination for Cd. In the most cost-effective operation mode, the material and energy costs of remediation amounted to 50.5 Euros ton(-1) soil and the total cost to 299 Euros ton(-1).

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

    Directory of Open Access Journals (Sweden)

    N.Karthika

    2016-01-01

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

  9. 100 Area soil washing bench-scale test procedures

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Gerber, M.A.; Mattigod, S.V.; Serne, R.J.

    1993-03-01

    This document describes methodologies and procedures for conducting soil washing treatability tests in accordance with the 100 Area Soil Washing Treatability Test Plan (DOE-RL 1992, Draft A). The objective of this treatability study is to evaluate the use of physical separation systems and chemical extraction methods as a means of separating chemically and radioactively contaminated soil fractions from uncontaminated soil fractions. These data will be primarily used for determining feasibility of the individual unit operations and defining the requirements for a system, or systems, for pilot-scale testing.

  10. Estimated ground-water recharge from streamflow in Fortymile Wash near Yucca Mountain, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Savard, C.S.

    1998-10-01

    The two purposes of this report are to qualitatively document ground-water recharge from stream-flow in Fortymile Wash during the period 1969--95 from previously unpublished ground-water levels in boreholes in Fortymile Canyon during 1982--91 and 1995, and to quantitatively estimate the long-term ground-water recharge rate from streamflow in Fortymile Wash for four reaches of Fortymile Wash (Fortymile Canyon, upper Jackass Flats, lower Jackass Flats, and Amargosa Desert). The long-term groundwater recharge rate was estimated from estimates of the volume of water available for infiltration, the volume of infiltration losses from streamflow, the ground-water recharge volume from infiltration losses, and an analysis of the different periods of data availability. The volume of water available for infiltration and ground-water recharge in the four reaches was estimated from known streamflow in ephemeral Fortymile Wash, which was measured at several gaging station locations. The volume of infiltration losses from streamflow for the four reaches was estimated from a streamflow volume loss factor applied to the estimated streamflows. the ground-water recharge volume was estimated from a linear relation between infiltration loss volume and ground-water recharge volume for each of the four reaches. Ground-water recharge rates were estimated for three different periods of data availability (1969--95, 1983--95, and 1992--95) and a long-term ground-water recharge rate estimated for each of the four reaches.

  11. Effect of soil washing with only chelators or combining with ferric chloride on soil heavy metal removal and phytoavailability: Field experiments.

    Science.gov (United States)

    Guo, Xiaofang; Wei, Zebin; Wu, Qitang; Li, Chunping; Qian, Tianwei; Zheng, Wei

    2016-03-01

    In a field experiment on multi-metal contaminated soil, we investigated the efficiency of Cd, Pb, Zn, and Cu removal by only mixture of chelators (MC) or combining with FeCl3. After washing treatment, a co-cropping system was performed for heavy metals to be extracted by Sedum alfredii and to produce safe food from Zea mays. We analyzed the concentration of heavy metals in groundwater to evaluate the leashing risk of soil washing with FeCl3 and MC. Results showed that addition of FeCl3 was favorable to the removal of heavy metals in the topsoil. Metal leaching occurred mainly in rain season during the first co-cropping. The removal rates of Cd, Zn, Pb, and Cu in topsoil were 28%, 53%, 41%, and 21% with washing by FeCl3+MC after first harvest. The application of FeCl3 reduced the yield of S. alfredii and increased the metals concentration of Z. mays in first harvest. However, after amending soil, the metals concentration of Z. mays in FeCl3+MC treatment were similar to that only washing by MC. The grains and shoots of Z. mays were safe for use in feed production. Soil washing did not worsen groundwater contamination during the study period. But the concentration of Cd in groundwater was higher than the limit value of Standard concentrations for Groundwater IV. This study suggests that soil washing using FeCl3 and MC for the remediation of multi-metal contaminated soil is potential feasibility. However, the subsequent measure to improve the washed soil environment for planting crop is considered.

  12. Changes in soil toxicity by phosphate-aided soil washing: effect of soil characteristics, chemical forms of arsenic, and cations in washing solutions.

    Science.gov (United States)

    Jho, Eun Hea; Im, Jinwoo; Yang, Kyung; Kim, Young-Jin; Nam, Kyoungphile

    2015-01-01

    This study was set to investigate the changes in the toxicity of arsenic (As)-contaminated soils after washing with phosphate solutions. The soil samples collected from two locations (A: rice paddy and B: forest land) of a former smelter site were contaminated with a similar level of As. Soil washing (0.5 M phosphate solution for 2 h) removed 24.5% As, on average, in soil from both locations. Regardless of soil washing, Location A soil toxicities, determined using Microtox, were greater than that of Location B and this could be largely attributed to different soil particle size distribution. With soils from both locations, the changes in As chemical forms resulted in either similar or greater toxicities after washing. This emphasizes the importance of considering ecotoxicological aspects, which are likely to differ depending on soil particle size distribution and changes in As chemical forms, in addition to the total concentration based remedial goals, in producing ecotoxicologically-sound soils for reuse. In addition, calcium phosphate used as the washing solution seemed to contribute more on the toxic effects of the washed soils than potassium phosphate and ammonium phosphate. Therefore, it would be more appropriate to use potassium or ammonium phosphate than calcium phosphate for phosphate-aided soil washing of the As-contaminated soils.

  13. Removal of arsenic from Janghang smelter site and energy crops-grown soil with soil washing using magnetic iron oxide

    Science.gov (United States)

    Han, Jaemaro; Zhao, Xin; Lee, Jong Keun; Kim, Jae Young

    2014-05-01

    Arsenic compounds are considered carcinogen and easily enter drinking water supplies with their natural abundance. US Environmental Protection Agency is finalizing a regulation to reduce the public health risks from arsenic in drinking water by revising the current drinking water standard for arsenic from 50 ppb to 10 ppb in 2001 (USEPA, 2001). Therefore, soil remediation is also growing field to prevent contamination of groundwater as well as crop cultivation. Soil washing is adjusted as ex-situ soil remediation technique which reduces volume of the contaminated soil. The technique is composed of physical separation and chemical extraction to extract target metal contamination in the soil. Chemical extraction methods have been developed solubilizing contaminants containing reagents such as acids or chelating agents. And acid extraction is proven as the most commonly used technology to treat heavy metals in soil, sediment, and sludge (FRTR, 2007). Due to the unique physical and chemical properties, magnetic iron oxide have been used in diverse areas including information technology and biomedicine. Magnetic iron oxides also can be used as adsorbent to heavy metal enhancing removal efficiency of arsenic concentration. In this study, magnetite is used as the washing agent with acid extraction condition so that the injected oxide can be separated by magnetic field. Soil samples were collected from three separate areas in the Janghang smelter site and energy crops-grown soil to have synergy effect with phytoremediation. Each sample was air-dried and sieved (2mm). Soil washing condition was adjusted on pH in the range of 0-12 with hydrogen chloride and sodium hydroxide. After performing soil washing procedure, arsenic-extracted samples were analyzed for arsenic concentration by inductively coupled plasma optical emission spectrometer (ICP-OES). All the soils have exceeded worrisome level of soil contamination for region 1 (25mg/kg) so the soil remediation techniques are

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

    Science.gov (United States)

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

    2017-04-01

    Soil washing is a promising way to remediate arsenic-contaminated soils. Most research has mostly focused on seeking efficient extractants for removing arsenic, but not concerned with any changes in soil properties when using this technique. In this study, the removal of arsenic from a heavily contaminated soil employing different washing solutions including H3PO4, NaOH and dithionite in EDTA was conducted. Subsequently, the changes in soil physicochemical properties and phytotoxicity of each washing technique were evaluated. After washing with 2 M H3PO4, 2 M NaOH or 0.1 M dithionite in 0.1 M EDTA, the soil samples' arsenic content met the clean-up levels stipulated in China's environmental regulations. H3PO4 washing decreased soil pH, Ca, Mg, Al, Fe, and Mn concentrations but increased TN and TP contents. NaOH washing increased soil pH but decreased soil TOC, TN and TP contents. Dithionite in EDTA washing reduced soil TOC, Ca, Mg, Al, Fe, Mn and TP contents. A drastic color change was observed when the soil sample was washed with H3PO4 or 0.1 M dithionite in 0.1 M EDTA. After adjusting the soil pH to neutral, wheat planted in the soil sample washed by NaOH evidenced the best growth of all three treated soil samples. These results will help with selecting the best washing solution when remediating arsenic-contaminated soils in future engineering applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Particle size separation via soil washing to obtain volume reduction.

    Science.gov (United States)

    Anderson, R; Rasor, E; Van Ryn, F

    1999-04-23

    A pilot-plant study was performed using a soil washing pilot plant originally designed by the Environmental Protection Agency (EPA) to demonstrate scale-up and potential full-scale remediation. This pilot plant named VORCE (Volume Reduction/Chemical Extraction) was modified to meet the specific requirements for treatment of the Formerly Utilized Sites Remedial Action Program (FUSRAP) and a Department of Energy site soils. After a series of tests on clean soils to develop operating parameters and system performance, the machine was used to treat soils, one contaminated with Thorium-232 and the other with Cesium-137. All indicate that soil washing is very promising for volume reduction treatment. In addition, cost data was generated and is given herein.

  16. Removal of uranium from gravel using soil washing method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ilgook; Kim, Kye-Nam; Kim, Seung-Soo; Choi, Jong-Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The development of nuclear technology has led to increasing radioactive waste containing uranium being released and disposed in the nuclear sites. Fine grained soils with a size of less than 4 mm are normally decontaminated using soil washing and electro-kinetic technologies. However, there have been few studies on the decontamination of gravels with a size of more than 4 mm. Therefore, it is necessary to study the decontamination of gravel contaminated with radionuclides. The main objective of the present study on soil washing was to define the optimal condition for acid treatment of uranium-polluted gravel. In this study, soil washing method was applied to remove uranium from gravel. The gravel was crushed and classified as particle sizes. The gravel particles were treated with sulfuric acid in a shaking incubator at 60 .deg. C and 150 rpm for 3 h. The optimal particle size of gravel for soil washing in removal of uranium was between 0.45 and 2.0 mm.

  17. WASHING STUDIES FOR PCP AND CREOSOTE-CONTAMINATED SOIL

    Science.gov (United States)

    The Environmental Protection Agency has conducted a series of bench-scale and pilot-scale studies to evaluate the feasibility of washing pentachlorophenol (PCP) and creosote from the soil at an abandoned wood-treatment Superfund site in Pensacola, FL. The high sand content and lo...

  18. Combined soil washing and CDEO for the removal of atrazine from soils

    OpenAIRE

    Vieira Santos, Elisama; Saez, C.; Martínez-Huitle, Carlos A.; Cañizares Cañizares, Pablo; Rodrigo Rodrigo, Manuel Andrés

    2015-01-01

    In this work, it is studied the removal of atrazine from spiked soils by soil washing using surfactant fluids, followed by the treatment of the resulting washing waste by electrolysis with boron doped diamond anode. Results confirm that combination of both technologies is efficient for the removal and total mineralization of atrazine. Ratio surfactant/soil is a key parameter for the removal of atrazine from soil and influences significantly in the characteristic of the wastewater produced, af...

  19. Ground-water recharge in Fortymile Wash near Yucca Mountain, Nevada, 1992--1993

    Energy Technology Data Exchange (ETDEWEB)

    Savard, C.S.

    1994-12-31

    Quantification of the ground-water recharge from streamflow in the Fortymile Wash watershed will contribute to regional ground-water studies. Regional ground-water studies are an important component in the studies evaluating the ground-water flow system as a barrier to the potential migration of radionuclides from the potential underground high-level nuclear waste repository. Knowledge gained in understanding the ground-water recharge mechanisms and pathways in the Pah Canyon area, which is 10 km to the northeast of Yucca Mountain, may transfer to Yucca site specific studies. The current data collection network in Fortymile Canyon does not permit quantification of ground-water recharge, however a qualitative understanding of ground-water recharge was developed from these data.

  20. Combined soil washing and CDEO for the removal of atrazine from soils

    Energy Technology Data Exchange (ETDEWEB)

    Vieira dos Santos, Elisama [Institute of Chemistry, Federal University of Rio Grande do Norte, Lagoa Nova CEP 59078-970, Natal, RN (Brazil); Sáez, Cristina [Department of Chemical Engineering, Universidad de Castilla – La Mancha, Enrique Costa Building, Campus Universitario s/n, 13071 Ciudad Real (Spain); Martínez-Huitle, Carlos Alberto [Institute of Chemistry, Federal University of Rio Grande do Norte, Lagoa Nova CEP 59078-970, Natal, RN (Brazil); Cañizares, Pablo; Rodrigo, Manuel Andres [Department of Chemical Engineering, Universidad de Castilla – La Mancha, Enrique Costa Building, Campus Universitario s/n, 13071 Ciudad Real (Spain)

    2015-12-30

    Highlights: • Sequential soil washing-waste electrolysis is an efficient treatment for removing atrazine. • Ratio surfactant/soil influences on the size of micelles and organic load. • Electrolysis with diamond anodes oxidizes pollutants from soils washing wastes. • Electrolysis of soil washing fluids promotes the reduction in size of micelles. • Sulphate ions release from the oxidation of SDS participates in the oxidation process. - Abstract: In this work, it is studied the removal of atrazine from spiked soils by soil washing using surfactant fluids, followed by the treatment of the resulting washing waste by electrolysis with boron doped diamond (BDD) anode. Results confirm that combination of both technologies is efficient for the removal and total mineralization of atrazine. Ratio surfactant/soil is a key parameter for the removal of atrazine from soil and influences significantly in the characteristic of the wastewater produced, affecting not only to the total organic load but also to the mean size of micelles. The higher the ratio surfactant soil, the lower is the size of the particles. Electrolyses of this type of waste attain the complete mineralization. TOC and COD are removed from the start of the treatment but the key of the treatment is the reduction in size of the micelles, which lead to a higher negative charge in the surface and to the faster depletion of the surfactant as compared with the pesticide.

  1. Physical separations soil washing system cold test results

    Energy Technology Data Exchange (ETDEWEB)

    McGuire, J.P.

    1993-07-28

    This test summary describes the objectives, methodology, and results of a physical separations soil-washing system setup and shakedown test using uncontaminated soil. The test is being conducted in preparation for a treatability test to be conducted in the North Pond of the 300-FF-1 Operable Unit. It will be used to assess the feasibility of using a physical separations process to reduce the volume of contaminated soils in the 300-FF-1 Operable Unit. The test is described in DOE-RL (1993). The setup test was conducted at an uncontrolled area located approximately 3.2 km northwest of the 300-FF-1 Operable Unit. The material processed was free of contamination. The physical separation equipment to be used in the test was transferred to the US Department of Energy (DOE) by the US Environmental Protection Agency (EPA) Risk Reduction Engineering Laboratory. On May 13, 1993, soil-washing equipment was moved to the cold test location. Design assistance and recommendation for operation was provided by the EPA.

  2. Effect of Soil Washing for Lead and Zinc Removal on Soil Hydraulic Properties

    Science.gov (United States)

    Kammerer, Gerhard; Zupanc, Vesna; Gluhar, Simon; Lestan, Domen

    2017-04-01

    Soil washing as a metal pollution remediation process, especially part with intensive mixing of the soil slurry and soil compression after de-watering, significantly deteriorates physical properties of soil compared to those of non-remediated soil. Furthermore, changed physical characteristics of remediated soil influence interaction of plant roots with soil system and affect soil water regime. Remediated soils showed significant differences to their original state in water retention properties and changed structure due to the influence of artificial structure created during remediation process. Disturbed and undisturbed soil samples of remediated and original soils were analyzed. We evaluated soil hydraulic properties as a possible constraint for re-establishing soil structure and soil fertility after the remediation procedure.

  3. 100 Area soil washing: Bench scale tests on 116-F-4 pluto crib soil

    Energy Technology Data Exchange (ETDEWEB)

    Field, J.G.

    1994-06-10

    The Pacific Northwest Laboratory conducted a bench-scale treatability study on a pluto crib soil sample from 100 Area of the Hanford Site. The objective of this study was to evaluate the use of physical separation (wet sieving), treatment processes (attrition scrubbing, and autogenous surface grinding), and chemical extraction methods as a means of separating radioactively-contaminated soil fractions from uncontaminated soil fractions. The soil washing treatability study was conducted on a soil sample from the 116-F-4 Pluto Crib that had been dug up as part of an excavation treatability study. Trace element analyses of this soil showed no elevated concentrations above typically uncontaminated soil background levels. Data on the distribution of radionuclide in various size fractions indicated that the soil-washing tests should be focused on the gravel and sand fractions of the 116-F-4 soil. The radionuclide data also showed that {sup 137}Cs was the only contaminant in this soil that exceeded the test performance goal (TPG). Therefore, the effectiveness of subsequent soil-washing tests for 116-F-4 soil was evaluated on the basis of activity attenuation of {sup 137}Cs in the gravel- and sand-size fractions.

  4. Evaluation of biosurfactants for crude oil contaminated soil washing.

    Science.gov (United States)

    Urum, Kingsley; Pekdemir, Turgay

    2004-12-01

    An evaluation of the ability of aqueous biosurfactant solutions (aescin, lecithin, rhamnolipid, saponin and tannin) for possible applications in washing crude oil contaminated soil was carried out. The biosurfactants behaviour in soil-water, water-oil and oil-soil systems (such as foaming, solubilization, sorption to soil, emulsification, surface and interfacial tension) was measured and compared with a well-known chemical surfactant (sodium dodecyl sulphate, SDS) at varying concentrations. Results showed that the biosurfactants were able to remove significant amount of crude oil from the contaminated soil at different solution concentrations for instance rhamnolipid and SDS removed up to 80% oil and lecithin about 42%. The performance of water alone in crude oil removal was equally as good as those of the other biosurfactants. Oil removal was due to mobilization, caused by the reduction of surface and interfacial tensions. Solubilization and emulsification effects in oil removal were negligible due to the low crude oil solubilization of 0.11%. Therefore, these studies suggest that knowledge of surfactants' behaviour across different systems is paramount before their use in the practical application of oil removal.

  5. [Strengthening Effects of Sodium Salts on Washing Kerosene Contaminated Soil with Surfactants].

    Science.gov (United States)

    Huang, Zhao-lu; Chen, Quan-yuan; Zhou, Juan; Xie, Mo-han

    2015-05-01

    The impact of sodium salt on kerosene contaminated soil washing with surfactants was investigated. The results indicated that sodium silicate greatly enhanced the washing efficiency of SDS. Sodium tartrate can largely enhance the washing efficiency of SDBS and Brij35. Sodium salts can enhance the washing efficiency on kerosene contaminated with TX-100. No significant differences were observed between different sodium salts. Sodium salt of humic acid and sodium silicate had similar enhancement on kerosene contaminated soil washing with saponin. Sodium humate can be a better choice since its application can also improve soil quality. The enhancement of sodium silicate on kerosene contaminated soil washing with Tw-80 increased with the increase of Tw-80 dosage. However, the impact of sodium chloride and sodium tartrate was opposite to sodium silicate. Sodium salts can reduce surface tension and critical micelle concentration of ionic surfactants to enhance the washing. Sodium salts can also reduce re-adsorption of oil to soil with nonionic surfactants to enhance the washing. Kerosene contamination can increase the contact angle of soil, which indicated the increase of hydrophilicity of soil. Washing with surfactants can reduce the hydrophilicitiy of soil according to contact angle measurement, which indicated that kerosene contaminated soil remediation with surfactant can also benefit nutrient and water transportation in the contaminated soil.

  6. Ultrasonic and mechanical soil washing processes for the remediation of heavy-metal-contaminated soil

    Science.gov (United States)

    Kim, Seulgi; Lee, Wontae; Son, Younggyu

    2016-07-01

    Ultrasonic/mechanical soil washing process was investigated and compared with ultrasonic process and mechanical process using a relatively large lab-scale sonoreactor. It was found that higher removal efficiencies were observed in the combined processes for 0.1 and 0.3 M HCl washing liquids. It was due to the combination effects of macroscale removal for the overall range of slurry by mechanical mixing and microscale removal for the limited zone of slurry by cavitational actions.

  7. Extraction agents for the removal of polycyclic aromatic hydrocarbons (PAHs) from soil in soil washing technologies.

    Science.gov (United States)

    Lau, Ee Von; Gan, Suyin; Ng, Hoon Kiat; Poh, Phaik Eong

    2014-01-01

    Polycyclic aromatic hydrocarbons (PAHs) in soil have been recognised as a serious health and environmental issue due to their carcinogenic, mutagenic and teratogenic properties. One of the commonly employed soil remediation techniques to clean up such contamination is soil washing or solvent extraction. The main factor which governs the efficiency of this process is the solubility of PAHs in the extraction agent. Past field-scale soil washing treatments for PAH-contaminated soil have mainly employed organic solvents or water which is either toxic and costly or inefficient in removing higher molecular weight PAHs. Thus, the present article aims to provide a review and discussion of the alternative extraction agents that have been studied, including surfactants, biosurfactants, microemulsions, natural surfactants, cyclodextrins, vegetable oil and solution with solid phase particles. These extraction agents have been found to remove PAHs from soil at percentages ranging from 47 to 100% for various PAHs.

  8. Ground-water recharge in Fortymile Wash near Yucca Mountain, Nevada, 1992-93

    Energy Technology Data Exchange (ETDEWEB)

    Savard, C.S. [Geological Survey, Mercury, NV (United States)

    1994-12-31

    Ground-water recharge occurred after five separate streamflow event periods in the Pah Canyon area of Fortymile Wash approximately 10 kilometers from Yucca Mountain, Nevada during 1992-93. Ground-water levels rose in two wells, UE-29 a No.1 and UE-29 a No.2, and one neutron-access borehole, UE-29 UZN-91, after each streamflow event period. A maximum rise of 2.9 meters occurred at UE-29 a No.1 thirteen days after the largest streamflow event where depth to water changed from 27.3 to 24.4 meters. Water levels fluctuated 3.89 meters in UE-29 a No.1, 2.92 meters in UE-29 a No.2, and 2.10 meters in UE-29 UZN-91 during the period January, 1992 to September, 1993. During two of the streamflow event periods, one in 1992 and one in 1993, there was flow around the neutron-access borehole located in the Fortymile Wash channel. Three other streamflow event periods were documented in Pah Canyon Wash but the streamflow infiltrated prior to reaching the neutron-access borehole location. Volumetric-water-content profiles were measured periodically in the neutron-access borehole. After the 1992 streamflow event period, water content increased in the upper six meters of the unsaturated zone. After the 1993 streamflow event period, water content increased in the entire unsaturated section, approximately 16 meters thick at the neutron-access borehole. Water levels in the neutron-access borehole rose even when there was no apparent water movement through the unsaturated zone as inferred by changes in the volumetric-water contents. This rise is attributed to ground-water recharge from nearby infiltration of Pah Canyon Wash streamflow. A groundwater mound probably formed beneath Pah Canyon Wash and spread laterally as evidence by larger rises in water levels in UE-29 a No.1 and UE-29 a No.2, which are closer to Pah Canyon Wash than UE-29 UZN-91.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-05-20

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

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

    Directory of Open Access Journals (Sweden)

    Jingchun Yan

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

  11. Ultrasonic and mechanical soil washing processes for the removal of heavy metals from soils.

    Science.gov (United States)

    Park, Beomguk; Son, Younggyu

    2017-03-01

    In order to determine the optimal operating conditions of full-scale soil washing processes for the removal of heavy metals, the effect of high-power ultrasound on the conventional mechanical soil washing process was investigated in a large lab-scale 28kHz sonoreactor. The soil samples were obtained from an abandoned railway station site in Seoul, Korea, which was contaminated with Cu (242.7±40.0mg/kg), Pb (441.3±49.8mg/kg), and Zn (358.0±35.7mg/kg). The treated concentrations of three heavy metal species in each process were compared with the regulation levels. It was found that higher performance, satisfying the regulation levels, was obtained in the ultrasonic/mechanical process due to the combined effects of macroscale mixing and microscale sonophysical effects. Moreover ultrasound played a more important role in less favorable conditions for the mechanical washing process (less acidic or less washing liquid conditions). Considering the application of the ultrasonic/mechanical soil washing process in real contaminated sites, the optimal conditions for the reactor with the bottom area of 15×15cm(2) and the input ultrasound power of 250W were determined as follows: (1) the amount of soil per an operation was a 300g; (2) the ratio of soil and liquid was 1:3; (3) the concentration of acidic washing liquid was 0.5M HCl. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. The source of groundwater and solutes to Many Devils Wash at a former uranium mill site in Shiprock, New Mexico

    Science.gov (United States)

    Robertson, Andrew J.; Ranalli, Anthony J.; Austin, Stephen A.; Lawlis, Bryan R.

    2016-04-21

    The Shiprock Disposal Site is the location of the former Navajo Mill (Mill), a uranium ore-processing facility, located on a terrace overlooking the San Juan River in the town of Shiprock, New Mexico. Following the closure of the Mill, all tailings and associated materials were encapsulated in a disposal cell built on top of the former Mill and tailings piles. The milling operations, conducted at the site from 1954 to 1968, created radioactive tailings and process-related wastes that are now found in the groundwater. Elevated concentrations of constituents of concern—ammonium, manganese, nitrate, selenium, strontium, sulfate, and uranium—have also been measured in groundwater seeps in the nearby Many Devils Wash arroyo, leading to the inference that these constituents originated from the Mill. These constituents have also been reported in groundwater that is associated with Mancos Shale, the bedrock that underlies the site. The objective of this report is to increase understanding of the source of water and solutes to the groundwater beneath Many Devils Wash and to establish the background concentrations for groundwater that is in contact with the Mancos Shale at the site. This report presents evidence on three working hypotheses: (1) the water and solutes in Many Devils Wash originated from the operations at the former Mill, (2) groundwater in deep aquifers is upwelling under artesian pressure to recharge the shallow groundwater beneath Many Devils Wash, and (3) the groundwater beneath Many Devils Wash originates as precipitation that infiltrates into the shallow aquifer system and discharges to Many Devils Wash in a series of springs on the east side of the wash. The solute concentrations in the shallow groundwater of Many Devils Wash would result from the interaction of the water and the Mancos Shale if the source of water was upwelling from deep aquifers or precipitation.In order to compare the groundwater from various wells to groundwater that has been

  13. The integration of innovative technologies into a physical-separation-based soil washing system

    Energy Technology Data Exchange (ETDEWEB)

    Krstich, M.A.

    1995-11-01

    An innovative system`s approach to the treatment of soils at the Fernald Environmental Management Project (FEMP) has been proposed to effectively and cost competitively treat a significant mass of soil. The use of an integrated soil treatment system to decontaminate FEMP soils is a unique application of the soil washing technology. Due to the unfavorable soil particle size distribution and the ubiquitous distribution of uranium among these particle size fractions, conventional soil washing processes commonly used on predominantly sandy soils alone may not achieve the desirable waste minimization level without the inclusion of innovative technologies. This objective of this paper is to briefly describe the physical separation and chemical extraction process commonly used in soil washing operation and to present the baseline soil washing approach used on FEMP soils. Noting the successful and not-so-successful processes within the soil washing operation at the FEMP, a proposed innovative system`s approach to treating FEMP soils will be described. This system`s approach will integrate a conventional soil washing operation with proposed innovative technologies.

  14. Study on optimal application of the ex-situ soil washing method to remove metals from polluted soils

    Directory of Open Access Journals (Sweden)

    Maria Szanto

    2011-08-01

    Full Text Available Overcoming the concentration of heavy metals in soil due to various polluting activitiesbecomes a major problem. Soil washing is a remediation method that uses water, inorganic or organicacids and chelating agents, becoming increasingly used for soil rehabilitation. Determination of the site`scharacteristics is the most important factor which depends on the soil washing method. Extraction ofheavy metals with the soil washing method is influenced by geological and hydrological characteristics,soil type and composition, pH, organic matter content, distribution of pollutants in soil, soil physical andchemical characteristics and pollution source. The present paper is a study on the conditions in which theextraction of metals from soil may be applied to obtain the best results and propose a suitable alternativesite remediation method by washing for heavily contaminated soils with heavy metals existing in ourcountry.

  15. Coagulation-flocculation process applied to wastewaters generated in hydrocarbon-contaminated soil washing

    Energy Technology Data Exchange (ETDEWEB)

    Torres, L. g.; Belloc, C.; Iturbe, R.; Bandala, E.

    2009-07-01

    A wastewater produced in the contaminated soil washing was treated by means of coagulation-flocculation (CF) process. the wastewater treatment in this work continued petroleum hydrocarbons, a surfactant, i. e., sodium dodecyl sulphate (SDS) as well as salts, humic acids and other constituents that were lixiviated rom the soil during the washing process. The aim of this work was to develop a process for treating the wastewaters generated when washing hydrocarbon-contaminated soils in such a way that it could be recycled to the washing process, and at the end of the cleaning up, the waters could be disposed properly. (Author)

  16. Removal of hydrophobic organic pollutants from soil washing/flushing solutions: A critical review.

    Science.gov (United States)

    Trellu, Clément; Mousset, Emmanuel; Pechaud, Yoan; Huguenot, David; van Hullebusch, Eric D; Esposito, Giovanni; Oturan, Mehmet A

    2016-04-01

    The release of hydrophobic organoxenobiotics such as polycyclic aromatic hydrocarbons, petroleum hydrocarbons or polychlorobiphenyls results in long-term contamination of soils and groundwaters. This constitutes a common concern as these compounds have high potential toxicological impact. Therefore, the development of cost-effective processes with high pollutant removal efficiency is a major challenge for researchers and soil remediation companies. Soil washing (SW) and soil flushing (SF) processes enhanced by the use of extracting agents (surfactants, biosurfactants, cyclodextrins etc.) are conceivable and efficient approaches. However, this generates high strength effluents containing large amount of extracting agent. For the treatment of these SW/SF solutions, the goal is to remove target pollutants and to recover extracting agents for further SW/SF steps. Heterogeneous photocatalysis, technologies based on Fenton reaction chemistry (including homogeneous photocatalysis such as photo-Fenton), ozonation, electrochemical processes and biological treatments have been investigated. Main advantages and drawbacks as well as target pollutant removal mechanisms are reviewed and compared. Promising integrated treatments, particularly the use of a selective adsorption step of target pollutants and the combination of advanced oxidation processes with biological treatments, are also discussed.

  17. Bench Scale Treatability Studies of Contaminated Soil Using Soil Washing Technique

    Directory of Open Access Journals (Sweden)

    M. K. Gupta

    2010-01-01

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

  18. Influence of EDTA washing on the species and mobility of heavy metals residual in soils.

    Science.gov (United States)

    Zhang, Weihua; Huang, Hao; Tan, Fenfang; Wang, Hong; Qiu, Rongliang

    2010-01-15

    Aiming to estimate the potential risk of ethylenediaminetetraacetic acid (EDTA)-enhanced soil washing, the heavy metal species and their mobility in the washed soil under different combinations were investigated by batch leaching tests and the sequential extraction procedure. Results demonstrate that the metal removal efficiency was rather low (less than 12%), partially due to the significant Ca dissolution and strong bonding between metals and the soil as well as the insufficient EDTA dosage. The washing combination of 0.0005 M EDTA and half-an-hour washing can enhance the instant mobility of Ni, Zn and Pb possibly owing to the slow detachment of EDTA-destabilized metals. Metal fractionation also exhibits the corresponding increase in their labile exchangeable fractions. Therefore, a more concentrated EDTA solution for a longer duration often decreased their mobility. The increase in some fractions of a curtain metal implies the redistribution of this metal during the EDTA soil washing. The pathway of such a redistribution may vary for different metals, but the redistribution to organic matter is often a slow process, while that to carbonates or Fe/Mn oxides is a faster one and even may occur in a half hour washing with 0.0005 M EDTA solution. These redistribution processes may also increase the metal chemical availability. Therefore, we should prudently control the chelating reagent concentration and washing duration to finally minimize the mobility and availability of the remaining heavy metals when designing the soil washing for the remediation of metal-contaminated soils.

  19. Chelant-enhanced washing of CCA-contaminated soil: Coupled with selective dissolution or soil stabilization.

    Science.gov (United States)

    Beiyuan, Jingzi; Lau, Abbe Y T; Tsang, Daniel C W; Zhang, Weihua; Kao, Chih-Ming; Baek, Kitae; Ok, Yong Sik; Li, Xiang-Dong

    2017-09-09

    Remediation of CCA-contaminated soil (Cr, Cu, and As) by biodegradable chelant-enhanced washing (EDDS, S,S-ethylene-diamine-disuccinic-acid) needs further enhancement. This study investigated the effectiveness of coupling with pre-treatment by selective dissolution and post-treatment by soil amendments, respectively. Three groups of reagents (reductants, alkaline solvents, and organic ligands) were adopted in the pre-treatment to dissolve the oxide minerals before EDDS extraction. In the post-treatment, soil amendments (coal fly ash (CFA), acid mine drainage sludge (AMDS), green waste compost (GWC)), and their mixtures) were used for a 2-month stabilization after 2-h EDDS washing. Multi-endpoint evaluation was performed by assessing the chemical state, leachability, mobility, bioaccessibility, and plant-availability of residual metal(loid)s as well as the cytotoxicity, enzyme activities, and available nutrients of the treated soils. Pre-treatment by dithionite-citrate-bicarbonate significantly enhanced extraction efficiency, but also increased the leachability of As and Cr and bioaccessibility of Cr in the treated soils. While sodium hydroxide removed the majority of As without increasing its leachability and bioaccessibility, it increased the cytotoxicity and inhibited the acid phosphatase activity. Post-treatment with AMDS and CFA effectively controlled the mobility and leachability of residual As and Cr after EDDS washing. However, destabilized Cu was only marginally immobilized by GWC due to strong Cu-EDDS complexation. The bioaccessibility and phytoavailability of Cu was primarily reduced by EDDS washing, while those of As and Cr could be attenuated by AMDS and CFA. This study indicates that coupling chemical extraction with subsequent soil amendment plays complementary roles in mitigating effects of residual metal(loid)s and improving environmental quality. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Evaluation of radiocaesium wash-off by soil erosion from various land uses using USLE plots.

    Science.gov (United States)

    Yoshimura, Kazuya; Onda, Yuichi; Kato, Hiroaki

    2015-01-01

    Radiocaesium wash-off associated with soil erosion in different land use was monitored using USLE plots in Kawamata, Fukushima Prefecture, Japan after the Fukushima Dai-ichi Nuclear Power Plant accident. Parameters and factors relating to soil erosion and (137)Cs concentration in the eroded soil were evaluated based on the field monitoring and presented. The erosion of fine soil, which is defined as the fraction of soil overflowed along with discharged water from a sediment-trap tank, constituted a large proportion of the discharged radiocaesium. This indicated that the quantitative monitoring of fine soil erosion is greatly important for the accurate evaluation of radiocaesium wash-off. An exponential relationship was found between vegetation cover and the amount of eroded soil. Moreover, the radiocaesium concentrations in the discharged soil were greatly affected by the land use. These results indicate that radiocaesium wash-off related to vegetation cover and land use is crucially important in modelling radiocaesium migration.

  1. The source of groundwater and solutes to Many Devils Wash at a former uranium mill site in Shiprock, New Mexico

    Science.gov (United States)

    Robertson, Andrew J.; Ranalli, Anthony J.; Austin, Stephen A.; Lawlis, Bryan R.

    2016-04-21

    The Shiprock Disposal Site is the location of the former Navajo Mill (Mill), a uranium ore-processing facility, located on a terrace overlooking the San Juan River in the town of Shiprock, New Mexico. Following the closure of the Mill, all tailings and associated materials were encapsulated in a disposal cell built on top of the former Mill and tailings piles. The milling operations, conducted at the site from 1954 to 1968, created radioactive tailings and process-related wastes that are now found in the groundwater. Elevated concentrations of constituents of concern—ammonium, manganese, nitrate, selenium, strontium, sulfate, and uranium—have also been measured in groundwater seeps in the nearby Many Devils Wash arroyo, leading to the inference that these constituents originated from the Mill. These constituents have also been reported in groundwater that is associated with Mancos Shale, the bedrock that underlies the site. The objective of this report is to increase understanding of the source of water and solutes to the groundwater beneath Many Devils Wash and to establish the background concentrations for groundwater that is in contact with the Mancos Shale at the site. This report presents evidence on three working hypotheses: (1) the water and solutes in Many Devils Wash originated from the operations at the former Mill, (2) groundwater in deep aquifers is upwelling under artesian pressure to recharge the shallow groundwater beneath Many Devils Wash, and (3) the groundwater beneath Many Devils Wash originates as precipitation that infiltrates into the shallow aquifer system and discharges to Many Devils Wash in a series of springs on the east side of the wash. The solute concentrations in the shallow groundwater of Many Devils Wash would result from the interaction of the water and the Mancos Shale if the source of water was upwelling from deep aquifers or precipitation.In order to compare the groundwater from various wells to groundwater that has been

  2. Vulnerability to diffuse pollution of European soils and groundwater

    NARCIS (Netherlands)

    Meinardi CR; Beusen AHW; Bollen MJS; Klepper O; LBG; CWM

    1994-01-01

    From the Atlantic Ocean to the Ural Mountains, European soils and groundwater are threatened by diffuse pollution derived from various chemicals used in modern agriculture and by increased atmospheric deposition of pollutants. The investigated vulnerability of soils (including groundwater) to

  3. Remediation of contaminated soil using soil washing and biopile methodologies at a field level

    Energy Technology Data Exchange (ETDEWEB)

    Iturbe, R.; Flores, C.; Chavez, C.; Bautista, G.; Torres, L.G. [Inst. de Ingenieria, Univ. Nacional Autonoma de Mexico, Coordinacion de Ingenieria Ambiental, Grupo Saneamiento de Suelos y Acuiferos, Coyoacn, Mexico, D.F. (Mexico)

    2004-07-01

    Background, aims and scope. An out-of-service oil distribution and storage station (ODSS), which operated from 1966 to 2000 in Mexico, is contaminated mainly by gasoline and diesel, showing the presence of methyl-tert-butyl-ether, benzene, toluene, ethyl benzene, and xylenes. Nine of the 16 polycyclic aromatic hydrocarbons were found, as well as Fe, Pb, V, and Zn. The health risk assessment suggested the necessity of reducing of three PAHs [benzo(a)anthracene, benzo(a)pyrene, and benzo(b)fluoranthene], and vanadium. The aim of this work is to show that soil washing (on-site) and biopiles are excellent remediation methodologies to treat soils contaminated with petroleum derivates and metals. Applying them, it is possible to reach the goal value of 2,000 mg TPH/kg in a few months, as requested by Mexican legislation. Methods. More than 140 m{sup 3} were excavated from the ODSS. Three soil-washing dishes were built. 1540 m{sup 3} were treated by soil washing using a nonionic surfactant. A 100 m{sup 3} biopile was built to study the system capabilities in the biodegradation of around 4,500 mg/kg of TPH using the autochthonous microflora. Results and discussion. The soil washing, average TPH-removal value was 83%, but values up to ca. 93% were observed. Removal values resulted in a function of the TPH initial values. Biopile (100 m{sup 3}) worked during 66 days, reaching a TPH-removal value of 85%. At the end of the processes, no PAHs were detected. The contaminated soil was treated successfully, reaching the legislation limits (TPH values under 2,000 mg/kg, and a significant reduction in PAH concentrations). Conclusion and recommendation. Both systems are suitable for remediation purposes, achieving high removal efficiencies at short and medium stages. It is highly recommended to proceed with soil washing studies, identifying new products, and mixtures, which could reduce costs and assure optimum operation. (orig.)

  4. Heavy metal removal by GLDA washing: Optimization, redistribution, recycling, and changes in soil fertility.

    Science.gov (United States)

    Wang, Guiyin; Zhang, Shirong; Xu, Xiaoxun; Zhong, Qinmei; Zhang, Chuer; Jia, Yongxia; Li, Ting; Deng, Ouping; Li, Yun

    2016-11-01

    Soil washing, an emerging method for treating soils contaminated by heavy metals, requires an evaluation of its efficiency in simultaneously removing different metals, the quality of the soil following remediation, and the reusability of the recycled washing agent. In this study, we employed N,N-bis (carboxymethyl)-l-glutamic acid (GLDA), a novel and readily biodegradable chelator to remove Cd, Pb, and Zn from polluted soils. We investigated the influence of washing conditions, including GLDA concentration, pH, and contact time on their removal efficiencies. The single factor experiments showed that Cd, Pb, and Zn removal efficiencies reached 70.62, 74.45, and 34.43% in mine soil at a GLDA concentration of 75mM, a pH of 4.0, and a contact time of 60min, and in polluted farmland soil, removal efficiencies were 69.12, 78.30, and 39.50%, respectively. We then employed response surface methodology to optimize the washing parameters. The optimization process showed that the removal efficiencies were 69.50, 88.09, and 40.45% in mine soil and 71.34, 81.02, and 50.95% in polluted farmland soil for Cd, Pb, and Zn, respectively. Moreover, the overall highly effective removal of Cd and Pb was connected mainly to their highly effective removal from the water-soluble, exchangeable, and carbonate fractions. GLDA-washing eliminated the same amount of metals as EDTA-washing, while simultaneously retaining most of the soil nutrients. Removal efficiencies of recycled GLDA were no >5% lower than those of the fresh GLDA. Therefore, GLDA could potentially be used for the rehabilitation of soil contaminated by heavy metals.

  5. Washing of Petroleum and Arsenic Contaminated Soil with Ultrasound and Alkali Phosphate Solution

    Science.gov (United States)

    Lee, Jung Hwa; Kim, Jae Gon; Cho, Yong-chan; Chon, Chul-Min; Nam, In-Hyun; Keum, Mi Jung

    2015-04-01

    Soil washing of fine textured soil has been a challenging remedial strategy due to its low remediation efficiency. We adapted ultrasound and dispersion solution to increase the remediation efficiency of the soil washing. The ultrasound and dispersion agent may enhance the dispersion of the aggregate into individual particles and may enhance release of contaminants from the aggregate. We collected the arsenic (As) contaminated silt loam soil from a smelting site, spiked with 1% of diesel and incubated for 6 months. We tested the dispersion rate and the release of diesel with the incubated soil at various pH and concentrations of orthophosphate, pyrophosphate and hexametaphosphate with or without the ultrasound of 28 kHz and 400 W. The As concentrations of coarse (> medium silt) and fine (soil washing was turned out to be pH 11_10 mM Na-hexametaphosphate with the ultrasound. The concentration of total petroleum hydrocarbon of the incubated soil reduced from 3101.3 mg kg-1 to 14.0 mg kg-1 after 10 minute washing at the optimum condition. The fine fraction had much higher As concentration than the coarse fraction: 44.4 mg kg-1 for the fine fraction and 14.4 mg kg-1 for the coarse fraction. The results of this study indicate that the ultrasound and alkali phosphate solution increase the soil washing efficiency and can be a promising technology for the remediation of fine textured contaminated soils. Key Words : Ultrasound, Phosphate solution, Soil washing, Mixed contaminants

  6. Comparison of energy consumptions between ultrasonic, mechanical, and combined soil washing processes.

    Science.gov (United States)

    Son, Younggyu; Nam, Sanggeon; Ashokkumar, Muthupandian; Khim, Jeehyeong

    2012-05-01

    Vigorous physical effects including micro-jet and micro-streaming can be induced in heterogeneous systems by acoustic cavitation. This can be useful for the removal of pollutants from contaminated soil particles. In this study, the diesel removal efficiencies in ultrasonic, mechanical, and combined soil washing processes have been compared considering the electrical energy consumptions for these processes. The combined process showed synergistic effects for both removal efficiency and effective volume also has the advantage of a short operation time compared to the sequential processes. Thus the ultrasonic soil washing process with mechanical mixing is considered a promising technology for industrial use. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Electrodialytic versus acid extraction of heavy metals from soil washing residue

    DEFF Research Database (Denmark)

    Jensen, Pernille E.; Ottosen, Lisbeth M.; Allard, Bert

    2012-01-01

    The feasibility of electrodialytic remediation (EDR) for treatment of suspended sludge after soil washing is in focus in the present paper. Five industrially contaminated soils were treated in laboratory scale remediation experiments, and the toxic elements of the investigation were: As, Cd, Cu, Cr...

  8. Acid washing and stabilization of an artificial arsenic-contaminated soil.

    Science.gov (United States)

    Tokunaga, Shuzo; Hakuta, Toshikatsu

    2002-01-01

    An acid-washing process was studied on a laboratory scale to extract the bulk of arsenic(V) from a highly contaminated Kuroboku soil (Andosol) so as to minimize the risk of arsenic to human health and the environment. The sorption and desorption behavior of arsenic in the soil suggested the possibility of arsenic leaching under acidic conditions. Artificially contaminated Kuroboku soil (2830 mg As/kg soil) was washed with different concentrations of hydrogen fluoride, phosphoric acid, sulfuric acid, hydrogen chloride, nitric acid, perchloric acid, hydrogen bromide, acetic acid, hydrogen peroxide, 3:1 hydrogen chloride-nitric acid, or 2:1 nitric acid-perchloric acid. Phosphoric acid proved to be most promising as an extractant, attaining 99.9% arsenic extraction at 9.4% acid concentration in 6 h. Sulfuric acid also attained high percentage extraction. The arsenic extraction by these acids reached equilibrium within 2 h. Elovich-type equation best described most of the kinetic data for dissolution of soil components as well as for extraction of arsenic. Dissolution of the soil components could be minimized by ceasing acid washing in 2 h. The acid-washed soil was further stabilized by the addition of lanthanum, cerium, and iron(III) salts or their oxides or hydroxides which form insoluble complex with arsenic. Both salts and oxides of lanthanum and cerium were effective in immobilizing arsenic in the soil attaining less than 0.01 mg/l As in the leaching test.

  9. Remediation of metal polluted hotspot areas through enhanced soil washing--evaluation of leaching methods.

    Science.gov (United States)

    Fedje, Karin Karlfeldt; Yillin, Li; Strömvall, Ann-Margret

    2013-10-15

    Soil washing offers a permanent remediation alternative for metal polluted sites. In addition, the washed out metals can be recovered from the leachate and re-introduced into the social material cycle instead of landfilled. In this paper, soil, bark and bark-ash washing was tested on four different metal polluted soil and bark samples from hotspots at former industrial sites. Six different leaching agents; HCl, NH4Cl, lactic acid, EDDS and two acidic process waters from solid waste incineration, were tested, discussed and evaluated. For the soil washing processes, the final pH in the leachate strongly influences the metal leachability. The results show that a pH leaching yield, while metals were leached when the pH was higher than 2 or below 10. The acidic process waste waters were generally the most efficient at leaching metals from all the samples studied, and as much as 90-100 w% of the Cu was released from some samples. Initial experiments show that from one of these un-purified leachates, Cu metal (>99% purity) could be recovered. After a single leaching step, the metal contents of the soil residues still exceed the maximum limits according to the Swedish guidelines. An additional washing step is needed to reduce the contents of easy soluble metal compounds in the soil residues. The overall results from this study show that soil and bark-ash washing followed by metal recovery is a promising on-site permanent alternative to remediate metal polluted soils and to utilize non-used metal resources.

  10. Remediation of polychlorinated biphenyl-contaminated soil by soil washing and subsequent TiO{sub 2} photocatalytic degradation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xiangdong; Fang, Guodong; Fan, Jianxin [Chinese Academy of Sciences, Nanjing (China). Key Laboratory of Soil Environment and Pollution Remediation; Graduate School of Chinese Academy of Sciences, Beijing (China); Zhou, Dongmei; Wang, Yujun; Cang, Long [Chinese Academy of Sciences, Nanjing (China). Key Laboratory of Soil Environment and Pollution Remediation

    2012-10-15

    An efficient method was developed for treating polychlorinated biphenyl (PCB)-contaminated soil by soil washing and subsequent TiO{sub 2} photocatalytic degradation, and the photocatalytic degradation mechanism of PCBs was explored. Hydroxypropyl-{beta}-cyclodextrin (HP{Beta}CD) and polyoxyethylene lauryl ether (Brij35) were used to extract PCBs from contaminated soil at first, and then the degradation of PCBs in the soil extracts was performed by TiO{sub 2} photocatalysis under UV irradiation. Washing conditions including washing time, the concentration of HP{Beta}CD/Brij35, and the ratio of soil mass to solution volume for extracting 2,4,4'-trichlorobiphenyl (PCB28) from a PCB28-spiked soil were investigated at first. The results indicated that both HP{Beta}CD and Brij35 exhibited good performance. The intermediates of photocatalytic degradation of PCB28 were from its dechlorination and hydroxylation in the HPCD and aqueous solutions, respectively. A field PCB-contaminated soil from e-waste recycling sites was treated by this method. The results showed that the extracting percentage was significantly affected by the chlorination degree of PCBs, and HP{Beta}CD slowed down the photocatalytic degradation efficiency of overall PCBs. Soil washing and subsequent TiO{sub 2} photocatalytic degradation was successfully applied for treating PCB-contaminated soil, and HP{Beta}CD strongly altered the pathways of the photocatalytic degradation of PCBs.

  11. General soil map Lower Pantano wash area, Pima County, Arizona

    Science.gov (United States)

    Richardson, M. L.

    1972-01-01

    High altitude color photography was used to determine soil type variation over large areas at a contact print scale of 1:125,000. It was found that color variation and land form could be used as a basis for assigning seven soil mapping units to the area as depicted on stereoscopic pairs of the color photography. A unit is assigned by soil scientists on the basis of similarity of soil features in the area to predetermined physical and chemical characteristics of the same soil type.

  12. Advances in the Coupled Soil Water and Groundwater Models

    Institute of Scientific and Technical Information of China (English)

    杨玉峥; 王志敏

    2014-01-01

    Models simulating the reciprocal transformation between the soil water and groundwater are of great practical importance to the development and utilization of water resources and prevention and remedy of water pollution. In this paper, popular coupled models of soil water and groundwater will be analyzed. Besides, advantages and disadvantages of different models will be summarized as a reference for the numerical model of soil water and groundwater.

  13. The Mechanism of Nitrate Pollution in Soil and Groundwater

    Institute of Scientific and Technical Information of China (English)

    王志敏; 诸葛敏; 杨玉峥

    2013-01-01

    Soil and groundwater which are important natural resources are closely related with human health.It will be hard to recover,if it is polluted.Nitrate has become one of the most serious harmful substances contaminated in soil and groundwater.A large number of studies have shown that high fertilizer and irrigation was the main reason of soil and groundwater pollution.Pollution is mainly concentrated in agricultural developed area.

  14. Mathematical evaluation of activated carbon adsorption for surfactant recovery in a soil washing process.

    Science.gov (United States)

    Ahn, Chi K; Lee, Min W; Lee, Dae S; Woo, Seung H; Park, Jong M

    2008-12-15

    The performances of various soil washing processes, including surfactant recovery by selective adsorption, were evaluated using a mathematical model for partitioning a target compound and surfactant in water/sorbent system. Phenanthrene was selected as a representative hazardous organic compound and Triton X-100 as a surfactant. Two activated carbons that differed in size (Darco 20-40 mesh and >100 mesh sizes) were used in adsorption experiments. The adsorption isotherms of the chemicals were used in model simulations for various washing scenarios. The optimal process conditions were suggested to minimize the dosage of activated carbon and surfactant and the number of washings. We estimated that the requirement of surfactant could be reduced to 33% of surfactant requirements (from 265 to 86.6g) with a reuse step using 9.1g activated carbon (>100 mesh) to achieve 90% removal of phenanthrene (initially 100mg kg-soil(-1)) with a water/soil ratio of 10.

  15. Removal of Pb and MDF from contaminated soils by EDTA- and SDS-enhanced washing.

    Science.gov (United States)

    Zhang, Weihua; Tsang, Daniel C W; Lo, Irene M C

    2007-02-01

    Heavy metal- and organic-contaminated sites are ubiquitous, but few studies have been conducted to address such an issue. EDTA- and SDS-enhanced washing was studied for remediation of Pb- and/or marine diesel fuel (MDF)-contaminated soils. The feasibility of recovery and reuse of EDTA and SDS, as well as the physicochemical interactions among the chemical agents, contaminants and soils were extensively investigated using batch experiments. The optimal washing sequence was then determined. The experimental results showed that EDTA could be recovered and reused for four cycles without significant loss of its chelating capacity, while the extraction capability of SDS was noticeably reduced after each reuse cycle. The free phase of marine diesel fuel (MDF) in soils physically isolated the sorbed Pb on soils and thus reducing its extraction by EDTA. The presence of SDS alone or together with low concentration of EDTA was found to enhance Pb removal probably via electrostatic interaction and dissolution of soil organic matter. However, it hindered Pb extraction by high concentration of EDTA, because of the potential formation of complexes between some strongly-bound Pb and SDS, that are more resistant to desorption. Therefore, EDTA washing followed by SDS achieved the highest Pb removal efficiency. On the other hand, MDF removal by SDS was significantly hindered by coexisting Pb in soils, probably because the formation of Pb-dodecyl sulfate (DS) complex would decrease the effective amount of SDS available for forming micelles in solution and enhance MDF sorption. EDTA alone or together with SDS could enhance MDF removal, but the residual MDF after EDTA-washing became more resistant to SDS removal. Consequently, SDS washing followed by EDTA is considered as the optimal washing sequence for MDF removal.

  16. Removal of oxyfluorfen from ex-situ soil washing fluids using electrolysis with diamond anodes.

    Science.gov (United States)

    dos Santos, Elisama Vieira; Sáez, Cristina; Martínez-Huitle, Carlos Alberto; Cañizares, Pablo; Rodrigo, Manuel Andres

    2016-04-15

    In this research, firstly, the treatment of soil spiked with oxyfluorfen was studied using a surfactant-aided soil-washing (SASW) process. After that, the electrochemical treatment of the washing liquid using boron doped diamond (BDD) anodes was performed. Results clearly demonstrate that SASW is a very efficient approach in the treatment of soil, removing the pesticide completely by using dosages below 5 g of sodium dodecyl sulfate (SDS) per Kg of soil. After that, complete mineralization of organic matter (oxyflourfen, SDS and by-products) was attained (100% of total organic carbon and chemical oxygen demand removals) when the washing liquids were electrolyzed using BDD anodes, but the removal rate depends on the size of the particles in solution. Electrolysis of soil washing fluids occurs via the reduction in size of micelles until their complete depletion. Lower concentrations of intermediates are produced (sulfate, chlorine, 4-(trifluoromethyl)-phenol and ortho-nitrophenol) during BDD-electrolyzes. Finally, it is important to indicate that, sulfate (coming from SDS) and chlorine (coming from oxyfluorfen) ions play an important role during the electrochemical organic matter removal.

  17. Copper Recovery from Polluted Soils Using Acidic Washing and Bioelectrochemical Systems

    Directory of Open Access Journals (Sweden)

    Karin Karlfeldt Fedje

    2015-07-01

    Full Text Available Excavation followed by landfilling is the most common method for treating soils contaminated by metals. However, as this solution is not sustainable, alternative techniques are required. Chemical soil washing is one such alternative. The aim of this experimental lab-scale study is to develop a remediation and metal recovery method for Cu contaminated sites. The method is based on the washing of soil or ash (combusted soil/bark with acidic waste liquids followed by electrolytic Cu recovery by means of bioelectrochemical systems (BES. The results demonstrate that a one- or two-step acidic leaching process followed by water washing removes >80 wt. % of the Cu. Copper with 99.7–99.9 wt. % purity was recovered from the acidic leachates using BES. In all experiments, electrical power was generated during the reduction of Cu. This clearly indicates that Cu can also be recovered from dilute solutions. Additionally, the method has the potential to wash co-pollutants such as polycyclic aromatic hydrocarbons (PAHs and oxy-PAHs.

  18. Vulnerability to diffuse pollution of European soils and groundwater

    NARCIS (Netherlands)

    Meinardi CR; Beusen AHW; Bollen MJS; Klepper O; LBG; CWM

    1994-01-01

    From the Atlantic Ocean to the Ural Mountains, European soils and groundwater are threatened by diffuse pollution derived from various chemicals used in modern agriculture and by increased atmospheric deposition of pollutants. The investigated vulnerability of soils (including groundwater) to diffus

  19. In-situ remediation system for groundwater and soils

    Science.gov (United States)

    Corey, J.C.; Kaback, D.S.; Looney, B.B.

    1991-01-01

    The present invention relates to a system for in-situ remediation of contaminated groundwater and soil. In particular the present invention relates to stabilizing toxic metals in groundwater and soil. The United States Government has rights in this invention pursuant to Contract No. DE-AC09-89SR18035 between the US Department of Energy and Westinghouse Savannah River Company.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-03-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-01-01

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

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

    Science.gov (United States)

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

    2016-02-01

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

  3. Arsenic bioavailability in soils before and after soil washing: the use of Escherichia coli whole-cell bioreporters.

    Science.gov (United States)

    Yoon, Youngdae; Kang, Yerin; Chae, Yooeun; Kim, Sunghoon; Lee, Youngshim; Jeong, Seung-Woo; An, Youn-Joo

    2016-02-01

    We investigated the quantification of bioavailable arsenic in contaminated soils and evaluation of soil-washing processes in the aspect of bioavailability using a novel bacterial bioreporter developed in present study. The whole-cell bioreporter (WCB) was genetically engineered by fusing the promoter of nik operon from Escherichia coli and green fluorescent protein as a sensing domain and reporter domain. Among eight well-known hazardous heavy metals and metalloid, this system responded specifically to arsenic, thereby inferring association of As(III) with NikR inhibits the repression. Moreover, the response was proportional to the concentration of As(III), thereby it was capable to determine the amount of bioavailable arsenic quantitatively in contaminated soils. The bioavailable portion of arsenic was 5.9 (3.46-10.96) and 0.9 (0.27-1.74) % of total from amended and site soils, respectively, suggesting the bioavailability of arsenic in soils was related to the soil properties and duration of aging. On the other hand, only 1.37 (0.21-2.97) % of total arsenic was extracted into soil solutions and 19.88 (11.86-28.27) % of arsenic in soil solution was bioavailable. This result showed that the soluble arsenic is not all bioavailable and most of bioavailable arsenic in soils is water non-extractable. In addition, the bioavailable arsenic was increased after soil-washing while total amount was decreased, thereby suggesting the soil-washing processes release arsenic associated with soil materials to be bioavailable. Therefore, it would be valuable to have a tool to assess bioavailability and the bioavailability should be taken into consideration for soil remediation plans.

  4. Effect of OSE(II)-Enhanced Soil Washing(OESW) for TPH -Contaminated Soil Remediation

    Science.gov (United States)

    Hwang, J. H.; Lee, D. H.; Woo, N. C.

    2015-12-01

    The objectives of this study were to perform potentially suitable active agent that solubilize total petroleum hydrocarbon (TPH) present as contaminants and to evaluate the optimal range of process parameters that can increase the removal efficiency in OSE(II)-enhanced soil washing (OESW) pilot tests. Used experimental method for solubilisation of TPH by using OSE(II) was batch experiments. The active agent solution parameters for OESW pilot tests were solution concentration, solution pH in the OESW pilot tests. Based on the batch experiments, OSE(II) was proved as a suitable active agent that solubilizes TPH present as contaminants. The highest recovery (92-95 %) of the contaminants was obtained using a OSE(II) in the batch experiments. The pilot test results revealed that the optimum conditions were achieved with a OSE(II) surfactant solution concentration of 10 % (v/v), a OSE(II) surfactant solution pH of 6.5-7.5 of OSE(II) active agent solution. The maximum removal of contaminants (88 %) was obtained when optimum conditions were simultaneously met in pilot-scale OESW operations. These results confirm the viability of OESW for treating TPH-contaminated soil.

  5. Using poly-glutamic acid as soil-washing agent to remediate heavy metal-contaminated soils.

    Science.gov (United States)

    Yang, Zong-Han; Dong, Cheng-Di; Chen, Chiu-Wen; Sheu, Yih-Terng; Kao, Chih-Ming

    2017-05-20

    The extraction efficiency of heavy metals from soils using three forms of gamma poly-glutamic acid (γ-PGA) as the washing agents was investigated. Controlling factors including agent concentrations, extraction time, pH, and liquid to soil ratio were evaluated to determine the optimum operational conditions. The distribution of heavy metal species in soils before and after extraction processes was analyzed. Up to 46 and 74% of heavy metal removal efficiencies were achieved with one round and a sequential extraction process using H-bonding form of γ-PGA (200 mM) with washing time of 40 min, liquid to solid ratio of 10 to 1, and pH of 6. Major heavy metal removal mechanisms were (1) γ-PGA-promoted dissolution and (2) complexation of heavy metal with free carboxyl groups in γ-PGA, which resulted in heavy metal desorption from soils. Metal species on soils were redistributed after washing, and soils were remediated without destruction of soil structures and productivity.

  6. Soil washing physical separations test procedure - 300-FF-1 operable unit

    Energy Technology Data Exchange (ETDEWEB)

    Belden, R.D.

    1993-10-08

    This procedure provides the operations approach, a field sampling plan, and laboratory procedures for a soil washing test to be conducted by Alternative Remedial Technologies, Inc. (ART) in the 300-FF-1 area at the Hanford site. The {open_quotes}Quality Assurance Project Plan for the Soil Washing Physical Separations Test, 300-FF-1 Operable Unit,{close_quotes} Hanford, Washington, Alternative Remedial Technologies, Inc., February 1994 (QAPP) is provided in a separate document that presents the procedural and organizational guidelines for this test. This document describes specifications, responsibilities, and general procedures to be followed to conduct physical separation soil treatability tests in the North Process Pond of the 300-FF-1 Operable Unit (OU) at the Hanford Site. These procedures are based on the {open_quotes}300-FF-1 Physical Separations CERCLA Treatability Test Plan, DOE/RL 92-2l,{close_quotes} (DOE-RL 1993).

  7. Soil moisture data as a constraint for groundwater recharge estimation

    Science.gov (United States)

    Mathias, Simon A.; Sorensen, James P. R.; Butler, Adrian P.

    2017-09-01

    Estimating groundwater recharge rates is important for water resource management studies. Modeling approaches to forecast groundwater recharge typically require observed historic data to assist calibration. It is generally not possible to observe groundwater recharge rates directly. Therefore, in the past, much effort has been invested to record soil moisture content (SMC) data, which can be used in a water balance calculation to estimate groundwater recharge. In this context, SMC data is measured at different depths and then typically integrated with respect to depth to obtain a single set of aggregated SMC values, which are used as an estimate of the total water stored within a given soil profile. This article seeks to investigate the value of such aggregated SMC data for conditioning groundwater recharge models in this respect. A simple modeling approach is adopted, which utilizes an emulation of Richards' equation in conjunction with a soil texture pedotransfer function. The only unknown parameters are soil texture. Monte Carlo simulation is performed for four different SMC monitoring sites. The model is used to estimate both aggregated SMC and groundwater recharge. The impact of conditioning the model to the aggregated SMC data is then explored in terms of its ability to reduce the uncertainty associated with recharge estimation. Whilst uncertainty in soil texture can lead to significant uncertainty in groundwater recharge estimation, it is found that aggregated SMC is virtually insensitive to soil texture.

  8. Humic substances from sewage sludge compost as washing agent effectively remove Cu and Cd from soil.

    Science.gov (United States)

    Kulikowska, Dorota; Gusiatin, Zygmunt Mariusz; Bułkowska, Katarzyna; Kierklo, Katarzyna

    2015-10-01

    Although commercially available biosurfactants are environmentally friendly and effectively remove heavy metals from soil, they are costly. Therefore, this study investigated whether inexpensive humic substances (HS) from sewage sludge compost could effectively remove copper (Cu) and cadmium (Cd) from highly contaminated sandy clay loam (S1) and clay (S2). The optimum HS concentration and pH were determined, as well process kinetics. Under optimum conditions, a single washing removed 80.7% of Cu and 69.1% of Cd from S1, and 53.2% and 36.5%, respectively, from S2. Triple washing increased removal from S1 to almost 100% for both metals, and to 83.2% of Cu and 88.9% of Cd from S2. Triple washing lowered the potential ecological risk (Er(i)) of the soils, especially the risk from Cd. HS substances show potential for treating soils highly contaminated with heavy metals, and HS from other sources should be tested with these and other contaminants.

  9. Use of Additives in Bioremediation of Contaminated Groundwater and Soil

    Science.gov (United States)

    This chapter reviews application of additives used in bioremediation of chlorinated solvents and fuels for groundwater and soil remediation. Soluble carbon substrates are applicable to most site conditions except aquifers with very high or very low groundwater flow. Slow-release ...

  10. Regional scale assessment of soil predictors of groundwater phosphate (P) levels in acidic sandy agricultural soils

    Science.gov (United States)

    Mabilde, Lisa

    2016-04-01

    Possible factors affecting the leaching of P to the groundwater in the Belgian sandy area are examined via regression analysis. The main objective is to investigate the dependency of phreatic groundwater phosphate concentrations (Flemish VMM monitoring net, monitoring period 2010-2013) on soil phosphate saturation degree (PSD) (1994-1997 mapping for Flemish Land Agency) (n = 1032). Additionally explored parameters include: depth distributions of Fe- and Al-oxides, sorbed P and phosphate sorption capacity (PSC) and soil pH. Interpolated data of these soil parameters in 3 depth layers (0-30, 30-60, 60-90 cm) were generated by ordinary kriging. Secondly, we assessed the significance of other edaphic factors potentially controlling the groundwater P: topsoil organic carbon content (OC %), soil clay content and fluctuation of the groundwater table. Overall, the mean PSD halved with each 30 cm depth layer (56 > 24 > 13 %) and was correlated to groundwater PO43- level. The statistical significance of the correlation with groundwater PO43- concentrations increased with depth layer. The poor correlation (R2 = 0.01) between PSD and groundwater phosphate concentration indicates that many factors, other than soil P status, control the transport of P from soil solution to the groundwater in Belgian sandy soils. A significant (PStructural equation modeling for example could be used to understand the practical importance of individual soil, management and hydrological potential predictors of groundwater PO4.

  11. Feed Forward Artificial Neural Network Model to Estimate the TPH Removal Efficiency in Soil Washing Process

    Directory of Open Access Journals (Sweden)

    Hossein Jafari Mansoorian

    2017-01-01

    Full Text Available Background & Aims of the Study: A feed forward artificial neural network (FFANN was developed to predict the efficiency of total petroleum hydrocarbon (TPH removal from a contaminated soil, using soil washing process with Tween 80. The main objective of this study was to assess the performance of developed FFANN model for the estimation of   TPH removal. Materials and Methods: Several independent repressors including pH, shaking speed, surfactant concentration and contact time were used to describe the removal of TPH as a dependent variable in a FFANN model. 85% of data set observations were used for training the model and remaining 15% were used for model testing, approximately. The performance of the model was compared with linear regression and assessed, using Root of Mean Square Error (RMSE as goodness-of-fit measure Results: For the prediction of TPH removal efficiency, a FANN model with a three-hidden-layer structure of 4-3-1 and a learning rate of 0.01 showed the best predictive results. The RMSE and R2 for the training and testing steps of the model were obtained to be 2.596, 0.966, 10.70 and 0.78, respectively. Conclusion: For about 80% of the TPH removal efficiency can be described by the assessed regressors the developed model. Thus, focusing on the optimization of soil washing process regarding to shaking speed, contact time, surfactant concentration and pH can improve the TPH removal performance from polluted soils. The results of this study could be the basis for the application of FANN for the assessment of soil washing process and the control of petroleum hydrocarbon emission into the environments.

  12. Selective Removal of Uranium from the Washing Solution of Uranium-Contaminated Soil

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Soo; Han, G. S.; Kim, G. N.; Koo, D. S.; Jeong, J. W.; Choi, J. W. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    This study examined selective removal methods of uranium from the waste solution by ion exchange resins or solvent extraction methods to reduce amount of the 2{sup nd} waste. Alamine-336, known as an excellent extraction reagent of uranium from the leaching solution of uranium ore, did not remove uranium from the acidic washing solution of soil. Uranyl ions in the acidic waste solution were sorbed on ampholyte resin with a high sorption efficiency, and desorbed from the resin by a washing with 0.5 M Na{sub 2}CO{sub 3} solution at 60 .deg. C. However, the uranium dissolved in the sulfuric acid solution was not sorbed onto the strong anion exchanger resins. A great amount of uranium-contaminated (U-contaminated) soil had been generated from the decommissioning of a uranium conversion plant. Our group has developed a decontamination process with washing and electrokinetic methods to decrease the amount of waste to be disposed of. However, this process generates a large amount of waste solution containing various metal ions.

  13. Sequential soil washing techniques using hydrochloric acid and sodium hydroxide for remediating arsenic-contaminated soils in abandoned iron-ore mines.

    Science.gov (United States)

    Jang, Min; Hwang, Jung Sung; Choi, Sang Il

    2007-01-01

    Sequential washing techniques using single or dual agents [sodium hydroxide (NaOH) and hydrochloric acid (HCl) solutions] were applied to arsenic-contaminated soils in an abandoned iron-ore mine area. We investigated the best remediation strategies to maximize arsenic removal efficiency for both soils and arsenic-containing washing solution through conducting a series of batch experiments. Based on the results of a sequential extraction procedure, most arsenic prevails in Fe-As precipitates or coprecipitates, and iron exists mostly in the crystalline forms of iron oxide. Soil washing by use of a single agent was not effective in remediating arsenic-contaminated soils because arsenic extractions determined by the Korean standard test (KST) methods for washed soils were not lower than 6mg kg(-1) in all experimental conditions. The results of X-ray diffraction (XRD) indicated that iron-ore fines produced mobile colloids through coagulation and flocculation in water contacting the soils, containing dissolved arsenic and fine particles of ferric arsenate-coprecipitated silicate. The first washing step using 0.2M HCl was mostly effective in increasing the cationic hydrolysis of amorphous ferrihydrite, inducing high removal of arsenic. Thus, the removal step of arsenic-containing flocs can lower arsenic extractions (KST methods) of washed soils. Among several washing trials, alternative sequential washing using 0.2M HCl followed by 1M HCl (second step) and 1M NaOH solution (third step) showed reliable and lower values of arsenic extractions (KST methods) of washed soils. This washing method can satisfy the arsenic regulation of washed soil for reuse or safe disposal application. The kinetic data of washing tests revealed that dissolved arsenic was easily readsorbed into remaining soils at a low pH. This result might have occurred due to dominant species of positively charged crystalline iron oxides characterized through the sequential extraction procedure. However

  14. Simulative models for the analysis of ground-water flow in Vekol Valley, the Waterman Wash area, and the Bosque area, Maricopa and Pina counties, Arizona

    Science.gov (United States)

    Matlock, D.T.

    1981-01-01

    Simulative ground-water flow models for Vekol Valley, the Waterman Wash area, and the Bosque area were developed for use in evaluating alternatives for developing a ground-water supply for the Ak-Chin Indian Community. The hydraulic properties of the basin-fill deposits used in the models were estimated primarily from aquifer tests made by the U.S. Geological Survey. Annual recharge to Vekol Valley and the Waterman Wash area is negligible in comparison to the quantity of water in storage and the quantity proposed to be pumped. The models are based on a three-dimensional, block-centered, finite-difference scheme. The Vekol Valley model was calibrated for steady-state onditions, and the Waterman Wash area model was calibrated for steady-state and transient conditions. The sensitivity of calibrated heads to changes in transmissivity was also investigated. An uncalibrated storage-depletion model was developed for the Bosque area. Simulated water levels for steady-state conditions average within 5 feet of measured values for Vekoi Valley and within 6 feet for the Waterman Wash area. Simulated water levels for transient conditions in the Waterman Wash area average within 8 feet of measured values for 15 years of analysis and within 15 feet for 24 years. Water-level declines simulated by the Waterman Wash area model average within 17 feet of those measured during the 24-year period, 1951-75.

  15. Sustainable Soil Washing: Shredded Card Filtration of Potentially Toxic Elements after Leaching from Soil Using Organic Acid Solutions.

    Directory of Open Access Journals (Sweden)

    Christopher Ash

    Full Text Available Shredded card (SC was assessed for use as a sorbent of potentially toxic elements (PTE carried from contaminated soil in various leachates (oxalic acid, formic acid, CaCl2, water. We further assessed SC for retention of PTE, using acidified water (pH 3.4. Vertical columns and a peristaltic pump were used to leach PTE from soils (O and A/B horizons before passing through SC. Sorption onto SC was studied by comparing leachates, and by monitoring total PTE contents on SC before and after leaching. SC buffers against acidic soil conditions that promote metals solubility; considerable increases in solution pH (+4.49 were observed. Greatest differences in solution PTE content after leaching with/without SC occurred for Pb. In oxalic acid, As, Cd, Pb showed a high level of sorption (25, 15, and 58x more of the respective PTE in leachates without SC. In formic acid, Pb sorption was highly efficient (219x more Pb in leachate without SC. In water, only Pb showed high sorption (191x more Pb in leachate without SC. In desorption experiments, release of PTE from SC varied according to the source of PTE (organic/mineral soil, and type of solvent used. Arsenic was the PTE most readily leached in desorption experiments. Low As sorption from water was followed by fast release (70% As released from SC. A high rate of Cd sorption from organic acid solutions was followed by strong retention (~12% Cd desorption. SC also retained Pb after sorption from water, with subsequent losses of ≤8.5% of total bound Pb. The proposed use of this material is for the filtration of PTE from extract solution following soil washing. Low-molecular-mass organic acids offer a less destructive, biodegradable alternative to strong inorganic acids for soil washing.

  16. Assessing soil and groundwater contamination in a metropolitan redevelopment project.

    Science.gov (United States)

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

    2013-08-01

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

  17. Study of electroflotation method for treatment of wastewater from washing soil contaminated by heavy metals

    Directory of Open Access Journals (Sweden)

    Izabel de Oliveira da Mota

    2015-04-01

    Full Text Available Electroflotation method (EFM for treatment of synthetic solutions simulating wastewater from washing soil contaminated by drilling fluids from oil wells was investigated in this paper. Experiments were carried out to examine the effects of the operating conditions on the removal of lead, barium and zinc from solutions containing 15 mg dm−3 for each metal representing a typical concentration of wastewater generated in the washing soil in this treatment. The experimental results showed that it is possible to remove these heavy metals by electrocoagulation/electroflotation (ECF attaining 97% of removal using stainless steel mesh electrodes with a power consumption of 14 kWh m−3. The optimal conditions of treatment were sodium dodecyl sulfate (SDS in a molar ratio 3:1, current density around 350 A m−2, ionic strength 3.2 × 10−3 M, pH = 10.0 and 20 min of ECF. This study newly indicated that the proposed method is adequate to simultaneously treat the common heavy metals found in the drilling fluids oil wells.

  18. Remediation trials for hydrocarbon-contaminated sludge from a soil washing process: evaluation of bioremediation technologies.

    Science.gov (United States)

    Frutos, F J García; Pérez, R; Escolano, O; Rubio, A; Gimeno, A; Fernandez, M D; Carbonell, G; Perucha, C; Laguna, J

    2012-01-15

    The usual fate of highly contaminated fine products (silt-clay fractions) from soil washing plants is disposal in a dump or thermal destruction (organic contaminants), with consequent environmental impacts. Alternative treatments for these fractions with the aim of on-site reuse are needed. Therefore, the feasibility of two technologies, slurry bioremediation and landfarming, has been studied for the treatment of sludge samples with a total petroleum hydrocarbon (TPH) content of 2243 mg/kg collected from a soil washing plant. The treatability studies were performed at the laboratory and pilot-real scales. The bioslurry assays yielded a TPH reduction efficiency of 57% and 65% in 28 days at the laboratory and pilot scale, respectively. In the landfarming assays, a TPH reduction of 85% in six months was obtained at laboratory scale and 42% in three months for the bioremediation performed in the full-scale. The efficiency of these processes was evaluated by ecotoxicity assessments. The toxic effects in the initial sludge sample were very low for most measured parameters. After the remediation treatments, a decrease in toxic effects was observed in earthworm survival and in carbon mineralisation. The results showed the applicability of two well known bioremediation technologies on these residues, this being a novelty.

  19. Removal of As, Cd, Cu, Ni, Pb, and Zn from a highly contaminated industrial soil using surfactant enhanced soil washing

    Science.gov (United States)

    Torres, Luis G.; Lopez, Rosario B.; Beltran, Margarita

    Surfactant enhanced soil washing (SESW) was applied to an industrial contaminated soil. A preliminary characterization of the soil regarding the alkaline-earth metals, Na, K, Ca and Mg took values of 2866, 2036, 2783 and 4149 mg/kg. The heavy metals As, Cd, Cu, Pb, Ni and Zn, had values of 4019, 14, 35582, 70, 2603, and 261 mg/kg, respectively. When using different surfactants, high removal of Cu, Ni and Zn were found, and medium removals for Pb, As and Cd. In the case of these three metals, tap water removed more than the surfactant solutions, except for the case of As. There were surfactants with average removals (this is, the removal for all the metals studied) of 67.1% (Tween 80), 64.9% (Surfacpol 14104) and 61.2% (Emulgin W600). There were exceptional removals using Texapon N-40 (83.2%, 82.8% and 86.6% for Cu, Ni and Zn), Tween 80 (85.9, 85.4 and 81.5 for Cd, Zn and Cu), Polafix CAPB (79%, 83.2% and 49.7% for Ni, Zn and As). The worst results were obtained with POLAFIX LO with a global removal of 45%, well below of the average removal with tap water (50.2%).All removal efficiencies are reported for a one step washing using 0.5% surfactant solutions, except for the case of mezquite gum, where a 0.1% solution was employed.

  20. Assessment and optimization of an ultrasound-assisted washing process using organic solvents for polychlorinated biphenyl-contaminated soil.

    Science.gov (United States)

    Bezama, Alberto; Flores, Alejandra; Araneda, Alberto; Barra, Ricardo; Pereira, Eduardo; Hernández, Víctor; Moya, Heriberto; Konrad, Odorico; Quiroz, Roberto

    2013-10-01

    The goal of this work was to evaluate a washing process that uses organic solutions for polychlorinated biphenyl (PCB)-contaminated soil, and includes an ultrasound pre-treatment step to reduce operational times and organic solvent losses. In a preliminary trial, the suitability of 10 washing solutions of different polarities were tested, from which three n-hexane-based solutions were selected for further evaluation. A second set of experiments was designed using a three-level Taguchi L27 orthogonal array to model the desorption processes of seven different PCB congeners in terms of the variability of their PCB concentration levels, polarity of the washing solution, sonication time, the ratio washing solution/soil, number of extraction steps and total washing time. Linear models were developed for the desorption processes of all congeners. These models provide a good fit with the results obtained. Moreover, statistically significant outcomes were achieved from the analysis of variance tests carried out. It was determined that sonication time and ratio of washing solution/soil were the most influential process parameters. For this reason they were studied in a third set of experiments, constructed as a full factorial design. The process was eventually optimized, achieving desorption rates of more than 90% for all congeners, thus obtaining concentrations lower than 5 ppb in all cases. The use of an ultrasound-assisted soil washing process for PCB-contaminated soils that uses organic solvents seems therefore to be a viable option, especially with the incorporation of an extra step in the sonication process relating to temperature control, which is intended to prevent the loss of the lighter congeners.

  1. Ultrasonic washing of textiles.

    Science.gov (United States)

    Choi, Junhee; Kim, Tae-Hong; Kim, Ho-Young; Kim, Wonjung

    2016-03-01

    We present the results of experimental investigation of ultrasonic washing of textiles. The results demonstrate that cavitation bubbles oscillating in acoustic fields are capable of removing soils from textiles. Since the washing performance is mitigated in a large washing bath when using an ultrasonic transducer, we propose a novel washing scheme by combining the ultrasonic vibration with a conventional washing method utilizing kinetic energy of textiles. It is shown that the hybrid washing scheme achieves a markedly enhanced performance up to 15% in comparison with the conventional washing machine. This work can contribute to developing a novel laundry machine with reduced washing time and waste water.

  2. Spatial Variations of Soil Microbial Activities in Saline Groundwater-Irrigated Soil Ecosystem.

    Science.gov (United States)

    Chen, Li-Juan; Feng, Qi; Li, Chang-Sheng; Song, You-Xi; Liu, Wei; Si, Jian-Hua; Zhang, Bao-Gui

    2016-05-01

    Spatial variations of soil microbial activities and its relationship with environmental factors are very important for estimating regional soil ecosystem function. Based on field samplings in a typical saline groundwater-irrigated region, spatial variations of soil microbial metabolic activities were investigated. Combined with groundwater quality analysis, the relationship between microbial activities and water salinity was also studied. The results demonstrated that moderate spatial heterogeneity of soil microbial activities presented under the total dissolved solids (TDS) of groundwater ranging from 0.23 to 12.24 g L(-1). Groundwater salinity and microbial activities had almost opposite distribution characteristics: slight saline water was mainly distributed in west Baqu and south Quanshan, while severe saline and briny water were dominant in east Baqu and west Huqu; however, total AWCD was higher in the east-center and southwest of Baqu and east Huqu, while it was lower in east Baqu and northwest Huqu. The results of correlation analyses demonstrated that high-salinity groundwater irrigation had significantly adverse effects on soil microbial activities. Major ions Ca(2+), Mg(2+), Cl(-), and SO4(2-) in groundwater decisively influenced the results. Three carbon sources, carbohydrates, amines, and phenols, which had minor utilization rates in all irrigation districts, were extremely significantly affected by high-salinity groundwater irrigation. The results presented here offer an approach for diagnosing regional soil ecosystem function changes under saline water irrigation.

  3. GROUNDWATER AND SOIL REMEDIATION USING ELECTRICAL FIELD

    Science.gov (United States)

    Enhancements of contaminants removal and degradation in low permeability soils by electrical fields are achieved by the processes of electrical heating, electrokinetics, and electrochemical reactions. Electrical heating increases soil temperature resulting in the increase of cont...

  4. Record of Decision Tank Farm Soil and INTEC Groundwater

    Energy Technology Data Exchange (ETDEWEB)

    L. S. Cahn

    2007-05-01

    This decision document presents the selected remedy for Operable Unit (OU) 3-14 tank farm soil and groundwater at the Idaho Nuclear Technology and Engineering Center (INTEC), which is located on the Idaho National Laboratory (INL) Site. The tank farm was initially evaluated in the OU 3-13 Record of Decision (ROD), and it was determined that additional information was needed to make a final decision. Additional information has been obtained on the nature and extent of contamination in the tank farm and on the impact of groundwater. The selected remedy was chosen in accordance with the Comprehensive Environmental Response, Liability and Compensation Act of 1980 (CERCLA) (42 USC 9601 et seq.), as amended by the Superfund Amendments and Reauthorization Act of 1986 (Public Law 99-499) and the National Oil and Hazardous Substances Pollution Contingency Plan (40 CFR 300). The selected remedy is intended to be the final action for tank far soil and groundwater at INTEC.

  5. Feasibility of phyto remediation of common soil and groundwater pollutants

    DEFF Research Database (Denmark)

    Trapp, Stefan; Rein, Arno; Clausen, Lauge Peter Westergaard

    his report is the D eliverable D 4.3 and was done within the Timbre project WP4. It introduces into the various clean - up techniques that apply plants, evaluates the feasibility of phytoremediation of common soil and groundwater pollutants, and the knowle dge collected for this purpose was applied...

  6. Feasibility of phytoremediation of common soil and groundwater pollutants

    DEFF Research Database (Denmark)

    Trapp, Stefan; Rein, Arno; Clause, Lauge

    2014-01-01

    This report is the D eliverable D 4.3 and was done within the Timbre project WP4. It introduces into the various clean - up techniques that apply plants, evaluates the feasibility of phytoremediation of common soil and groundwater pollutants, and the knowle dge collected for this purpose...

  7. The impact of groundwater level on soil seed bank survival

    NARCIS (Netherlands)

    Bekker, RM; Oomes, MJM; Bakker, JP

    Seed longevity of plant species is an important topic in restoration management, and little is known about the effects of environmental conditions on seed survival and longevity under natural conditions. Therefore, the effect of groundwater level on the survival of seeds in the soil seed bank of a

  8. Metal ions removal from wastewater or washing water from contaminated soil by ultrafiltration-complexation.

    Science.gov (United States)

    Molinari, Raffaele; Gallo, Saverio; Argurio, Pietro

    2004-02-01

    In the present paper a process for removal of ions from wastewater or from washing water of contaminated soil by using the weakly basic water-soluble polymer polyethylenimine (PEI) as chelating agent and the Cu(2+) ion as model in combination with an ultrafiltration process was investigated. The complexing agent was preliminarily tested to establish the best operative conditions of the process. Next, ultrafiltration tests by using five different membranes were realised to check membrane performance like flux and rejection. Finally, the possibility for recovering and recycling the polymer was tested in order to obtain an economically sustainable process. Obtained results showed that complexation conditions depends on pH: indeed, at a pH>6 PEI-Cu(2+) complexes are formed, while at pHultrafiltration process (PAUF) very interesting for metal ion removal from waters.

  9. Removal of heavy metals from polluted soil using the citric acid fermentation broth: a promising washing agent.

    Science.gov (United States)

    Zhang, Hongjiao; Gao, Yuntao; Xiong, Huabin

    2017-04-01

    The citric acid fermentation broth was prepared and it was employed to washing remediation of heavy metal-polluted soil. A well-defined washing effect was obtained, the removal percentages using citric acid fermentation broth are that 48.2% for Pb, 30.6% for Cu, 43.7% for Cr, and 58.4% for Cd and higher than that using citric acid solution. The kinetics of heavy metals desorption can be described by the double constant equation and Elovich equation and is a heterogeneous diffusion process. The speciation analysis shows that the citric acid fermentation broth can effectively reduce bioavailability and environmental risk of heavy metals. Spectroscopy characteristics analysis suggests that the washing method has only a small effect on the mineral composition and does not destroy the framework of soil system. Therefore, the citric acid fermentation broth is a promising washing agent and possesses a potential practical application value in the field of remediation of soils with a good washing performance.

  10. Spray washing, absorbent cornstarch powder, and dry time to reduce bacterial numbers on soiled transport cage flooring

    Science.gov (United States)

    Broiler transport cages are often used repeatedly without washing and fecal matter deposited on the floor surface can transfer Campylobacter from one flock to another. Allowing feces to dry is an effective but slow and logistically impractical means to kill Campylobacter in soiled transport cages. ...

  11. Selective dissolution followed by EDDS washing of an e-waste contaminated soil: Extraction efficiency, fate of residual metals, and impact on soil environment.

    Science.gov (United States)

    Beiyuan, Jingzi; Tsang, Daniel C W; Valix, Marjorie; Zhang, Weihua; Yang, Xin; Ok, Yong Sik; Li, Xiang-Dong

    2017-01-01

    To enhance extraction of strongly bound metals from oxide minerals and organic matter, this study examined the sequential use of reductants, oxidants, alkaline solvents and organic acids followed by a biodegradable chelating agent (EDDS, [S,S]-ethylene-diamine-disuccinic-acid) in a two-stage soil washing. The soil was contaminated by Cu, Zn, and Pb at an e-waste recycling site in Qingyuan city, China. In addition to extraction efficiency, this study also examined the fate of residual metals (e.g., leachability, bioaccessibility, and distribution) and the soil quality parameters (i.e., cytotoxicity, enzyme activities, and available nutrients). The reductants (dithionite-citrate-bicarbonate and hydroxylamine hydrochloride) effectively extracted metals by mineral dissolution, but elevated the leachability and bioaccessibility of metals due to the transformation from Fe/Mn oxides to labile fractions. Subsequent EDDS washing was found necessary to mitigate the residual risks. In comparison, prior washing by oxidants (persulphate, hypochlorite, and hydrogen peroxide) was marginally useful because of limited amount of soil organic matter. Prior washing by alkaline solvents (sodium hydroxide and sodium bicarbonate) was also ineffective due to metal precipitation. In contrast, prior washing by low-molecular-weight organic acids (citrate and oxalate) improved the extraction efficiency. Compared to hydroxylamine hydrochloride, citrate and oxalate induced lower cytotoxicity (Microtox) and allowed higher enzyme activities (dehydrogenase, acid phosphatase, and urease) and soil nutrients (available nitrogen and phosphorus), which would facilitate reuse of the treated soil. Therefore, while sequential washing proved to enhance extraction efficacy, the selection of chemical agents besides EDDS should also include the consideration of effects on metal leachability/bioaccessibility and soil quality. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Soil washing of chromium- and cadmium-contaminated sludge using acids and ethylenediaminetetra acetic acid chelating agent.

    Science.gov (United States)

    Gitipour, Saeid; Ahmadi, Soheil; Madadian, Edris; Ardestani, Mojtaba

    2016-01-01

    In this research, the effect of soil washing in the removal of chromium- and cadmium-contaminated sludge samples collected from Pond 2 of the Tehran Oil Refinery was investigated. These metals are considered as hazardous substances for human health and the environment. The carcinogenicity of chromate dust has been established for a long time. Cadmium is also a potential environmental toxicant. This study was carried out by collecting sludge samples from different locations in Pond 2. Soil washing was conducted to treat the samples. Chemical agents, such as acetic acid, ethylenediaminetetra acetic acid (EDTA) and hydrochloric acid, were used as washing solutions to remove chromium and cadmium from sludge samples. The results of this study indicated that the highest removal efficiencies from the sludge samples were achieved using a 0.3 M HCl solution with 82.69% and 74.47% for chromium and cadmium, respectively. EDTA (0.1 M) in the best condition extracted 66.81% of cadmium and 72.52% of chromium from the sludges. The lowest efficiency values for the samples, however, were achieved using 3 M acetic acid with 41.7% and 46.96% removals for cadmium and chromium, respectively. The analysis of washed sludge indicated that the heavy metals removal decreased in the order of 3 M acetic acid acid appears to offer a greater potential as a washing agent in remediating the sludge samples.

  13. Multivariate hydrological data assimilation of soil moisture and groundwater head

    Science.gov (United States)

    Zhang, Donghua; Madsen, Henrik; Ridler, Marc E.; Kidmose, Jacob; Jensen, Karsten H.; Refsgaard, Jens C.

    2016-10-01

    Observed groundwater head and soil moisture profiles are assimilated into an integrated hydrological model. The study uses the ensemble transform Kalman filter (ETKF) data assimilation method with the MIKE SHE hydrological model code. The method was firstly tested on synthetic data in a catchment of less complexity (the Karup catchment in Denmark), and later implemented using data from real observations in a larger and more complex catchment (the Ahlergaarde catchment in Denmark). In the Karup model, several experiments were designed with respect to different observation types, ensemble sizes and localization schemes, to investigate the assimilation performance. The results showed the necessity of using localization, especially when assimilating both groundwater head and soil moisture. The proposed scheme with both distance localization and variable localization was shown to be more robust and provide better results. Using the same assimilation scheme in the Ahlergaarde model, groundwater head and soil moisture were successfully assimilated into the model. The hydrological model with assimilation showed an overall improved performance compared to the model without assimilation.

  14. Removal of heavy metals and arsenic from a co-contaminated soil by sieving combined with washing process.

    Science.gov (United States)

    Liao, Xiaoyong; Li, You; Yan, Xiulan

    2016-03-01

    Batch experiments were conducted with a heavy metals and arsenic co-contaminated soil from an abandoned mine to evaluate the feasibility of a remediation technology that combines sieving with soil washing. Leaching of the arsenic and heavy metals from the different particle size fractions was found to decrease in the order: 2mm. With increased contact time, the concentration of heavy metals in the leachate was significantly decreased for small particles, probably because of adsorption by the clay soil component. For the different particle sizes, the removal efficiencies for Pb and Cd were 75%-87%, and 61%-77% for Zn and Cu, although the extent of removal was decreased for As and Cr at soil particles >2mm, although good metal removal efficiencies were also achieved in the small particle size fractions. Through SEM-EDS observations and correlation analysis, the leaching regularity of the heavy metals and arsenic was found to be closely related to Fe, Mn, and Ca contents of the soil fractions. The remediation of heavy metal-contaminated soil by sieving combined with soil washing was proven to be efficient, and practical remediation parameters were also recommended.

  15. Soil decontamination at the Montevecchio-Levante mine site with experimental washing and leaching techniques

    Energy Technology Data Exchange (ETDEWEB)

    Dessi, R. [Progemisa SpA, Cagliari (Italy); Fadda, S.; Peretti, R.; Zucca, A. [CSGM, Centro Studi Germinerari e Mineralurgici del CNR, Cagliari (Italy); Serci, A. [Digita, Dipt. di Geoingegneria e Tecnologie Ambientali, Cagliari (Italy)

    2000-12-01

    The soils in the neighbourhood of the Rio Montevecchio-Sitzerri, a stream that flows in the valley below the tailings pond of the Montevecchio-Levante mineral processing plant (SW Sardinia, Italy) are severely contaminated by heavy metals, to the extent that traditional land uses are compromised. Consequently urgent measures are needed both to abate the pollution at source and rehabilitate the contaminated land. This paper is concerned with the problem of soil decontamination using washing and leaching techniques. Laboratory experiments have been conducted in mechanically agitated reactors, using citric acid and acetic acid solutions and brine of hydrochloric acid and calcium chloride. The influence of both reagent concentration and solid-to-liquid ratio has been assessed, and in the most significant cases, the attack kinetics has been determined. The tests showed the brine to be the most effective for removing metals from the soils. Based on the findings of the investigations, the possibility of decontamination by heap leaching has been simulated in the laboratory using the column technique. [Italian] I suoi circostanti il Rio Montevecchio-Sitzerri, che scorre a valle del bacino di decantazione degli sterili dell'impianto di trattamento dei minerali di Montevecchio-Levante (Sardegna Centro-Occidentale), sono caratterizzati da un elevato contenuto di metalli pesanti, che ne pregiudicano gli usi tradizionali. Si rende percio' improrogabile sia la necessita' di intervenire sulle cause all'origine della contaminazione, sia di bonificare i suoli in questione al fine di recuperarli a nuovi usi. La memoria intende portare un contributo alle relative problematiche affrontando la possibilita' di decontaminazione mediante tecniche di lavaggio e lisciviazione. La sperimentazione di laboratorio e' stata condotta in reattori ad agitazione meccanica, utilizzando soluzioni con acido citrico, acido acetico ed una salamoia costituita da acido

  16. Soil CO2 Uptake in Deserts and Its Implications to the Groundwater Environment

    Directory of Open Access Journals (Sweden)

    Wenfeng Wang

    2016-09-01

    Full Text Available Recent studies of soil carbon cycle in arid and semi-arid ecosystems demonstrated that there exists an abiotic CO2 absorption by saline-alkali soils (Aa at desert ecosystems and suggested potential contributions of CO2 dissolution beneath deserts to the terrestrial ecosystems carbon balance. However, the overall importance of such soil CO2 uptake is still undetermined and its implications to the groundwater environment remain unaddressed. In this manuscript, a simple method is proposed for the direct computation of Aa from the total soil CO2 flux (Fa as well as for the evaluation of Aa importance to Fa. An artificial soil-groundwater system was employed to investigate the implications to groundwater environment and it was found that soil CO2 uptake in deserts can contribute a possible influence on the evolution of the groundwater environment, providing that the absorbed CO2 largely remained in the soil-groundwater system.

  17. Soil washing in combination with homogeneous Fenton-like oxidation for the removal of 2,4,4'-trichlorodiphenyl from soil contaminated with capacitor oil.

    Science.gov (United States)

    Ma, Xiao-Hong; Zhao, Ling; Lin, Zhi-Rong; Dong, Yuan-Hua

    2016-04-01

    Detoxification by chemical oxidation of polychlorinated biphenyls (PCBs) in contaminated soils is very difficult and inefficient because PCBs typically associate with the solid phase or exist as non-aqueous-phase liquids due to their low solubility and slow desorption rates, and thus, they are difficult to remove from soils by using traditional, water-based elution techniques. Surfactant can enhance washing efficiency of PCBs from contaminated soils. This study used Brij 58, Brij 30, Tween 80, and 2-hydroxypropyl-β-cyclodextrin (HPCD) to solubilize 2,4,4'-trichlorodiphenyl (PCB28) from soil contaminated with capacitor oil into solution. The feasibility of PCB28 oxidation in soil washing wastewater through a Fe(3+)-catalyzed Fenton-like reaction was subsequently examined. Washing with 10 g L(-1) Brij 58 solution showed the highest extraction efficiency (up to 61.5 %) compared with that of the three other surfactants. The total concentration of PCB28 in contaminated soil at 25 °C after 48-h extraction was 286 mg L(-1). In contrast to conditions in which no washing agent was added, addition of the four washing agents decreased the efficiency of PCB28 degradation by the Fenton-like reaction, with the decrease due to addition of 10 g L(-1) Brij 58 solution being the smallest. The optimal concentration of H2O2 for preventing its useless decomposition was found to be 50 mM. The efficiency of PCB28 removal was lower when the initial concentration of PCB28 treated in the Fenton-like reaction was higher. The degradation efficiencies of PCB28 at initial concentrations of 0.1, 10, and 176 mg L(-1) in 10 g L(-1) Brij 58 solution at 25 °C and pH 3.0 and 9 h of reaction using 50 mM H2O2 were 64.1, 42.0, and 34.6 %, respectively. This result indicates that soil washing combined with Fenton-like oxidation may be a practical approach for the remediation of PCB-contaminated soil.

  18. PRIMARY ANALYSIS ON GROUNDWATER, SOIL MOISTURE AND SALINITY IN FUKANG OASIS OF SOUTHERN JUNGGAR BASIN

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Soil salinity is the most important factor affecting vegetation distribution, and the secondary salinizationhas affected the development of oasis agriculture. In arid areas the spatial variation of soil moisture and salt content is marked-ly affected by groundwater, irrational irrigation in artificial oasis. By analyzing the soil moisture, salt content and groundwa-ter table in different areas of old oasis, new oasis and desert in Fukang Oasis, it is shown that topography and land useare main factors affecting the change of groundwater table, the redistribution of soil moisture and salt content. When undis-turbed by human, the groundwater table rises from mountain to belt of ground water spillage, the groundwater table risesmightily in plain because of the artificial irrigation, and the secondary salinization of soil is very serious. In oasis the ground-water table raises compared with that in the natural desert at the same latitude. In old oasis of upper reaches of river salthas not been concentrated too much in rhizosphere because this area is the belt of groundwater drainage, soil texture iscoarse, the groundwater table is very low, and the salt in soil is drained into the groundwater. The new oasis has beenthe areas of salt accumulation because of the artificial irrigation, the salt content in soil is higher than that in old oasis,so some cultivated fields here had to be thrown out because of the serious secondary salinization.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-12-31

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

  20. Using ERS spaceborne microwave soil moisture observations to predict groundwater head in space and time

    NARCIS (Netherlands)

    Sutanudjaja, E.H.; De Jong, S.M.; Van Geer, F.C.; Bierkens, M.F.P.

    2013-01-01

    The study presented in this paper is to investigate the possibility of using spaceborne remote sensing data for groundwater head prediction. Remotely-sensed soil moisture time series of SWI (Soil Water Index) derived from ERS (European Remote Sensing) scatterometers are used to predict groundwater

  1. Using ERS spaceborne microwave soil moisture observations to predict groundwater heads in space and time

    NARCIS (Netherlands)

    Sutanudjaja, E.H.; Jong, S.M. de; Bierkens, M.F.P.; Geer, F.C. van

    2013-01-01

    The study presented in this paper is to investigate the possibility of using spaceborne remote sensing data for groundwater head prediction. Remotely-sensed soil moisture time series of SWI (Soil Water Index) derived from ERS (European Remote Sensing) scatterometers are used to predict groundwater

  2. Flooding forested groundwater recharge areas modifies microbial communities from top soil to groundwater table.

    Science.gov (United States)

    Schütz, Kirsten; Nagel, Peter; Vetter, Walter; Kandeler, Ellen; Ruess, Liliane

    2009-01-01

    Subsurface microorganisms are crucial for contaminant degradation and maintenance of groundwater quality. This study investigates the microbial biomass and community composition [by phospholipid fatty acids (PLFAs)], as well as physical and chemical soil characteristics at woodland flooding sites of an artificial groundwater recharge system used for drinking water production. Vertical soil profiles to c. 4 m at two watered and one nonwatered site were analyzed. The microbial biomass was equal in watered and nonwatered sites, and considerable fractions (25-42%) were located in 40-340 cm depth. The microbial community structure differed significantly between watered and nonwatered sites, predominantly below 100 cm depth. Proportions of the bacterial PLFAs 16:1omega5, 16:1omega7, cy17:0 and 18:1omega9t, and the long-chained PLFAs 22:1omega9 and 24:1omega9 were more prominent at the watered sites, whereas branched, saturated PLFAs (iso/anteiso) dominated at the nonwatered site. PLFA community indices indicated stress response (trans/cis ratio), higher nutrient availability (unsaturation index) and changes in membrane fluidity (iso/anteiso ratio) due to flooding. In conclusion, water recharge processes led to nutrient input and altered environmental conditions, which resulted in a highly active and adapted microbial community residing in the vadose zone that effectively degraded organic compounds.

  3. Remediation of organochlorine pesticides (OCPs) contaminated site by successive methyl-β-cyclodextrin (MCD) and sunflower oil enhanced soil washing - Portulaca oleracea L. cultivation.

    Science.gov (United States)

    Ye, Mao; Sun, Mingming; Hu, Feng; Kengara, Fredrick Orori; Jiang, Xin; Luo, Yongming; Yang, Xinlun

    2014-06-01

    An innovative ex situ soil washing technology was developed in this study to remediate organochlorine pesticides (OCPs)-contaminated site. Elevated temperature (50 °C) combined with ultrasonication (35 kHz, 30 min) at 25 g L(-1) methyl-β-cyclodextrin and 100 mL L(-1) sunflower oil were effective in extracting OCPs from the soil. After four successive washing cycles, the removal efficiency for total OCPs, DDTs, endosulfans, 1,2,3,4,5,6-hexachlorocyclohexanes, heptachlors, and chlordanes were all about 99%. The 4th washed soil with 3 months cultivation of Portulaca oleracea L. and nutrient addition significantly increase (p<0.05) the number, biomass carbon, nitrogen, and functioning diversity of soil microorganisms. This implied that the microbiological functioning of the soil was at least partially restored. This combined cleanup strategy proved to be effective and environmental friendly.

  4. Potential of activated carbon to recover randomly-methylated-β-cyclodextrin solution from washing water originating from in situ soil flushing.

    Science.gov (United States)

    Sniegowski, K; Vanhecke, M; D'Huys, P-J; Braeken, L

    2014-07-01

    Despite the overall high efficacy of cyclodextrins to accelerate the treatment of soil aquifer remediation by in-situ soil flushing, the use in practice remains limited because of the high costs of cyclodextrin and high concentrations needed to significantly reduce the treatment time. The current study tested the potential of activated carbon to treat washing water originating from soil flushing in order to selectively separate hydrocarbon contaminants from washing water containing cyclodextrin and subsequently reuse the cyclodextrin solution for reinfiltration. A high recovery of the cyclodextrin from the washing water would reduce the costs and would make the technique economically feasible for soil remediation. This study aimed to investigate whether cyclodextrin can pass through the activated carbon filter without reducing the cyclodextrin concentration when the contaminated washing water is treated and whether the presence of cyclodextrin negatively affects the purification potential of activated carbon to remove the organic pollutants from the pumped soil water. Lab-scale column experiments showed that with the appropriate activated carbon 100% of cyclodextrin (randomly-methylated-β-cyclodextrin) can be recovered from the washing water and that the effect on the efficiency of activated carbon to remove the hydrocarbon contaminants remains limited. These results show that additional field tests are useful to make in-situ soil flushing with cyclodextrin both a technical and an economical interesting technique. These results might stimulate the application of cyclodextrin in soil treatment technology.

  5. Soil washing/flushing of contaminated soil:A review%污染土壤淋洗修复技术研究进展

    Institute of Scientific and Technical Information of China (English)

    李玉双; 胡晓钧; 孙铁珩; 侯永侠; 宋雪英; 杨继松; 陈红亮

    2011-01-01

    Soil washing/flushing is an efficient technology for rapid remediation of soils or sediments highly contaminated by heavy metals and/or organic pollutants. In this paper, the characteristics, technical processes, and cleaning agents for soil washing/flushing remediation were reviewed. The ex-site soil washing has broad application prospects, due to its stable remediation efficiency, easy control, and waste reduction. Environment-friendly cleaning agents, such as natural chelating agents and bio-surfactants, have gradually replaced artificial chelating agents and chemical surfactants, and become the main cleaning agents for soil washing/flushing. Modern supramolecular chemistry will have significance in the washing/flushing remediation of soils contaminated by combined pollutants.%土壤淋洗修复技术是一种行之有效的污染土壤治理技术,适合干快速修复受高浓度重金属和有机物污染土壤与沉积物.本文综述了土壤淋洗修复技术的特点、技术流程、土壤淋洗剂的研究与应用进展,指出异位土壤淋洗修复技术因修复效果稳定,易于实现系统控制和废弃物减量化等优点而具有更广阔的应用前景,天然螯合剂和生物表面活性剂等环境友好型淋洗剂正逐渐取代人工螯合剂和化学表面活性剂成为土壤淋洗剂研究的主流方向,而现代超分子化学的引入和发展有可能对复合污染土壤的高效淋洗修复研究产生新的影响.

  6. Integrating EDDS-enhanced washing with low-cost stabilization of metal-contaminated soil from an e-waste recycling site.

    Science.gov (United States)

    Beiyuan, Jingzi; Tsang, Daniel C W; Ok, Yong Sik; Zhang, Weihua; Yang, Xin; Baek, Kitae; Li, Xiang-Dong

    2016-09-01

    While chelant-enhanced soil washing has been widely studied for metal extraction from contaminated soils, there are concerns about destabilization and leaching of residual metals after remediation. This study integrated 2-h soil washing enhanced by biodegradable ethylenediaminedisuccinic acid (EDDS) and 2-month stabilization using agricultural waste product (soybean stover biochar pyrolyzed at 300 and 700 °C), industrial by-product (coal fly ash (CFA)), and their mixture. After integration with 2-month stabilization, the leachability and mobility of residual metals (Cu, Zn, and Pb) in the field-contaminated soil were significantly reduced, especially for Cu, in comparison with 2-h EDDS washing alone. This suggested that the metals destabilized by EDDS-washing could be immobilized by subsequent stabilization with biochar and CFA. Moreover, when the remediation performance was evaluated for phytoavailability and bioaccessibility, prior EDDS washing helped to achieve a greater reduction in the bioavailable fraction of metals than sole stabilization treatment. This was probably because the weakly-bound metals were first removed by EDDS washing before stabilization. Both individual and combined applications of biochar and CFA showed comparable effectiveness regardless of the difference in material properties, possibly due to the high level of amendments (150 ton ha(-1)). Based on the mobility and bioaccessibility results, the estimated human health risk (primarily resulting from Pb) could be mitigated to an acceptable level in water consumption pathway or reduced by half in soil ingestion pathway. These results suggest that an integration of EDDS washing with soil stabilization can alleviate post-remediation impacts of residual metals in the treated soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Hydrochemical Analysis and Evaluation of Groundwater Quality and Agriculture Soil of Khairpur Taluka, Sindh, Pakistan

    Directory of Open Access Journals (Sweden)

    Tajnees Pirzada

    2016-06-01

    Full Text Available The inhabitants of Khairpur Taluka mostly consume groundwater for drinking and agriculture purposes. The present study was conducted to monitor the essential quality parameters of groundwater and soil. Both groundwater and soil samples of the area were classified as alkaline. All the major ions except Na and SO4 were found within the permissible limits, while the concentrations of Zn, Fe, Co, Pb, Ni and Mn in studied groundwater samples were found above the specified limit of WHO. However, soil samples were found rich in major and trace elements except Cd, which was low in comparison to world average of agriculture soil. Irrigation character of water samples on SAR vs. Na% plot display fair type with few exceptions. The piper diagram implied mixed water composition with Na-Ca-Mg and HCO3-SO4+Cl as dominate ions. Diverse shapes of Stiff polygons also support the mixed nature of groundwater in the study area.

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

    Science.gov (United States)

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

    2011-11-30

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

  9. Simulation of large-scale soil water systems using groundwater data and satellite based soil moisture

    Science.gov (United States)

    Kreye, Phillip; Meon, Günter

    2016-04-01

    Complex concepts for the physically correct depiction of dominant processes in the hydrosphere are increasingly at the forefront of hydrological modelling. Many scientific issues in hydrological modelling demand for additional system variables besides a simulation of runoff only, such as groundwater recharge or soil moisture conditions. Models that include soil water simulations are either very simplified or require a high number of parameters. Against this backdrop there is a heightened demand of observations to be used to calibrate the model. A reasonable integration of groundwater data or remote sensing data in calibration procedures as well as the identifiability of physically plausible sets of parameters is subject to research in the field of hydrology. Since this data is often combined with conceptual models, the given interfaces are not suitable for such demands. Furthermore, the application of automated optimisation procedures is generally associated with conceptual models, whose (fast) computing times allow many iterations of the optimisation in an acceptable time frame. One of the main aims of this study is to reduce the discrepancy between scientific and practical applications in the field of hydrological modelling. Therefore, the soil model DYVESOM (DYnamic VEgetation SOil Model) was developed as one of the primary components of the hydrological modelling system PANTA RHEI. DYVESOMs structure provides the required interfaces for the calibrations made at runoff, satellite based soil moisture and groundwater level. The model considers spatial and temporal differentiated feedback of the development of the vegetation on the soil system. In addition, small scale heterogeneities of soil properties (subgrid-variability) are parameterized by variation of van Genuchten parameters depending on distribution functions. Different sets of parameters are operated simultaneously while interacting with each other. The developed soil model is innovative regarding concept

  10. 铅蓄电池厂铅污染土壤清洗剂的筛选及清洗结果研究%Washing Agents Selection for Soils Polluted by Lead in Lead Battery Factory and Corresponding Washing Results

    Institute of Scientific and Technical Information of China (English)

    任贝; 苗明升; 黄锦楼

    2012-01-01

    To explore the lead removal of different washing agents for soil polluted by lead in lead battery factory and the lead behavior during washing process in soils with different sized particles, this paper studies the size grading of the soil particles and setting the washing time based on setting different concentration gradient of washing agents. The results show that the optimal lead removal rates of EDTA and EDDS are 107.19% and 96.49% respectively for the soil at site B; and that of hydrochloric acid for soils at point A, B and C are 49.57% , 99.03% and 89.93% ; for soils at the three point, the highest remove rate of citric acid is 39.51% , while all the three removal rates of rhamnolipid are less than 10% ; EDTA and EDDS performances show advantage in soil polluted by high concentration lead; citric acid is suitable for soil with medium or low lead concentration; application of hydrochloric acid should consider the soil situation. The lead removal rates are high for coarse sands and fine sands, but low for the silt soil; the optimum washing time is 240 minutes. In addition, the physical and chemical properties of soil affect the washing performance, and over high washing agent concentration may reduce the efficiency. This study provides scientific basis for the technology of washing soil polluted by lead.%为探索不同清洗剂对铅蓄电池厂区内铅污染土壤的去除效果及铅在不同粒径土壤清洗过程中的行为,本研究通过设定清洗剂的浓度梯度,对土样粒径分级、设定清洗时间等方法进行研究。结果显示EDTA和EDDS对铅具有最佳去除率(B点土107.19%和96.49%);盐酸对A点土最佳铅去除率为49.57%,B点、C点土在99.03%和89.93%;柠檬酸对3点位土的铅去除率最大为39.51%;鼠李糖脂对3份土铅去除率均低于10%。EDTA和EDDS在高浓度铅的去除中表现优势;柠檬酸适合去除中低浓度铅;盐酸的使用需考虑土壤本身

  11. Scientific Opportunity to Reduce Risk in Groundwater and Soil Remediation

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Eric M.; Freshley, Mark D.; Hubbard, Susan S.; Looney, Brian B.; Zachara, John M.; Liang, Liyuan; Lesmes, D.; Chamberlain, G. M.; Skubal, Karen L.; Adams, V.; Denham, Miles E.; Wellman, Dawn M.

    2009-08-25

    In this report, we start by examining previous efforts at linking science and DOE EM research with cleanup activities. Many of these efforts were initiated by creating science and technology roadmaps. A recurring feature of successfully implementing these roadmaps into EM applied research efforts and successful cleanup is the focus on integration. Such integration takes many forms, ranging from combining information generated by various scientific disciplines, to providing technical expertise to facilitate successful application of novel technology, to bringing the resources and creativity of many to address the common goal of moving EM cleanup forward. Successful projects identify and focus research efforts on addressing the problems and challenges that are causing “failure” in actual cleanup activities. In this way, basic and applied science resources are used strategically to address the particular unknowns that are barriers to cleanup. The brief descriptions of the Office of Science basic (Environmental Remediation Science Program [ERSP]) and EM’s applied (Groundwater and Soil Remediation Program) research programs in subsurface science provide context to the five “crosscutting” themes that have been developed in this strategic planning effort. To address these challenges and opportunities, a tiered systematic approach is proposed that leverages basic science investments with new applied research investments from the DOE Office of Engineering and Technology within the framework of the identified basic science and applied research crosscutting themes. These themes are evident in the initial portfolio of initiatives in the EM groundwater and soil cleanup multi-year program plan. As stated in a companion document for tank waste processing (Bredt et al. 2008), in addition to achieving its mission, DOE EM is experiencing a fundamental shift in philosophy from driving to closure to enabling the long-term needs of DOE and the nation.

  12. Contamination valuation of soil and groundwater source at anaerobic municipal solid waste landfill site.

    Science.gov (United States)

    Aziz, Shuokr Qarani; Maulood, Yousif Ismael

    2015-12-01

    The present work aimed to determine the risks that formed landfill leachate from anaerobic Erbil Landfill Site (ELS) poses on groundwater source and to observe the effects of disposed municipal solid waste (MSW) on soil properties. The study further aims to fill the gap in studies on the effects of disposed MSW and produced leachate on the groundwater characteristics and soil quality at ELS, Iraq. Soil, leachate, and groundwater samples were collected from ELS for use as samples in this study. Unpolluted groundwater samples were collected from an area outside of the landfill. Field and laboratory experiments for the soil samples were conducted. Chemical analyses for the soil samples such as organic matter, total salts, and SO4 (=) were also performed. Raw leachate and groundwater samples were analyzed using physical and chemical experiments. The yields for sorptivity, steady-state infiltration rate, and hydraulic conductivity of the soil samples were 0.0006 m/√s, 0.00004 m/s, and 2.17 × 10(-5) m/s, respectively. The soil at ELS was found to be light brown clayey gravel with sand and light brown gravely lean clay layers with low permeability. Unprocessed leachate analysis identified the leachate as stabilized. Findings showed that the soil and groundwater at the anaerobic ELS were contaminated.

  13. Denitrification as an adaptive trait in soil and groundwater bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Bergwall, C.

    1997-09-01

    The focus of this thesis is on selection and adaptation processes in bacteria with emphasis on denitrifying bacteria in groundwater. Other nitrogen transformation processes such as dissimilatory nitrate reduction to ammonium (nitrate ammonification) and nitrification of forest soil bacteria are briefly discussed. Microcosms with sterile sediment and groundwater were inoculated with single denitrifying strains isolated from three groundwater aquifers, two of which are agricultural aquifers (in situ NO{sub 3}{sup -}-N was 24.1 and 35.2 mg1{sup -1}) and the third which is a pristine lake water infiltration aquifer (in situ NO{sub 3}{sup -}-N was 6.3 mg1{sup -1}). The average denitrification activity for strains from the nitrate contaminated sites were twice as high as the activity of the strains from the pristine site. Denitrification were carbon limited and glucose amendment increased the denitrification activity about a 2-fold for all strains. The strain specific differences in denitrification rates increased to a 2.5-fold after carbon addition indicating that the differences in reduction rates cannot be explained by different carbon utilisation rates but rather reflect innate differences in the reductases of the strains. A preliminary identification of the molecular target for adaptation was performed with artificial electron donors and electron acceptors for all enzymatic steps in the denitrification pathway. Nitrous oxide reductase activity was significantly higher in denitrifiers from the nitrate contaminated sites. This suggests that nos genes may be the molecular target, possibly by mutation or gene duplication for adaptation to high nitrate concentrations. Two anaerobic denitrifiers from each of the contaminated sites were capable of aerobic denitrification indicating that high nitrate concentrations may select for strains that denitrifies in the presence of both oxygen and nitrate. Microcosm experiments with fertilized coniferous forest soil showed that the

  14. Evidence for groundwater contamination by heavy metals through soil passage under acidifying conditions

    OpenAIRE

    Wilkens, B. J.

    1995-01-01

    The research reported here is aimed at improving the knowledge of the mobility of the heavy metals cadmium and zinc in vulnerable soil types. We use the term vulnerable with reference to vulnerability of groundwater for contamination by soil leaching. At diffuse soil immissions of heavy metals, accumulation is often supposed to occur mainly in the topsoil. Binding of heavy metals in this soil compartment is relatively strong, because of de presence of soil organic matter, clay-minerals and se...

  15. Application of Photo-Fenton Process for COD Removal from Wastewater Produced from Surfactant-Washed  Oil-Contaminated (TPH Soils

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Mehrasbi

    2012-10-01

    Full Text Available Backgrounds and Objectives: The base structure of total petroleum hydrocarbons (TPH is made of hydrogen and carbon. Widespread use, improper disposal and accidental spills of this compounds lead to long term remaining of contaminations such as organic solvents and poly aromatic hydrocarbons (PAHs in the soil and groundwater resources, resulting in critical environmental issues. In this study, an oil-contaminated soil was washed using Tween 80 surfactant and the application of photo-Fenton process (UV/Fe2+/H2O2 for treatment of the produced wastewater was evaluated. Materials and Methods: Tween 80 is a yellow liquid with high viscosity and soluble in water. In order to determine of the photo-Fenton process efficiency, we studied effective variables including Fe concentration, pH, H2O2 concentration, and irradiation time. The UV irradiation source was a medium-pressure mercury vapor lamp (400 w vertically immersed in the solution within 2L volume glass cylindrical reactor.Results: The results showed that efficiency of COD removal depends on the initial Fe concentration, pH, H2O2 concentration and irradiation time. Under optimum conditions, (Fe: 0.1mM, H2O2: 0.43 mM, pH: 3 and UV light irradiation time: 2 hours the removal efficiency of COD was 67.3%. pH plays a crucial role in the photo-Fenton process such that the removal efficiency increased with decreasing of pH. Conclusion: According to the results of this study, under acidic condition, this process is an efficient method for COD removal from the wastewater studied.

  16. Evidence for groundwater contamination by heavy metals through soil passage under acidifying conditions

    NARCIS (Netherlands)

    Wilkens, B.J.

    1995-01-01

    The research reported here is aimed at improving the knowledge of the mobility of the heavy metals cadmium and zinc in vulnerable soil types. We use the term vulnerable with reference to vulnerability of groundwater for contamination by soil leaching. At diffuse soil immissions of heavy metals, accu

  17. Nitrate leaching to groundwater at experimental farm "De Marke" and other Dutch sandy soils

    NARCIS (Netherlands)

    Hack-ten Broeke, M.J.D.

    2001-01-01

    This study focuses on nitrate leaching to the groundwater as a result of the land use system of experimental farm 'De Marke', translated to other sandy soils in the Netherlands. The land use was extrapolated to five major sandy soil map units, selected from the 1: 50 000 Soil Map of the Netherlands,

  18. Migration of infiltrated NH4 and NO3 in a soil and groundwater system simulated by a soil tank

    Institute of Scientific and Technical Information of China (English)

    WANG Chao; WANG Pei-Fang

    2008-01-01

    The infiltration of water contaminants into soil and groundwater systems can greatly affect the quality of groundwater.A laboratory-designed large soil tank with periodic and continuous infiltration models,respectively,was used to simulate the migration of the contaminants NHa and NO3 in a soil and groundwater system,including unsaturated and saturated zones.The unsaturated soil zone had a significant effect on removing NH4 and NO3 infiltrated from the surface water.The patterns of breakthrough curves of NH4 and NO3 in the unsaturated zone were related to the infiltration time.A short infiltration time resulted in a single sharp peak in the breakthrough curve,while a long infiltration time led to a plateau curve.When NHa and NO3 migrated from the unsaturated zone to the saturated zone,an interfacial retardation was formed,resulting in an increased contaminant concentration on the interface.Under the influence of horizontal groundwater movement,the infiltrated contaminants formed a contamination-prone area downstream.As the contaminants migrated downstream,their concentrations were significantly reduced.Under the same infiltration concentration,the concentration of NO3 was greater than that of NH4 at every corresponding cross-section in the soil and groundwater tank,suggesting that the removal efficiency of NH4 was greater than that of NO3 in the soil and groundwater system.

  19. Phytoremediation of contaminated soils and groundwater: lessons from the field

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-11-01

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

  20. DEPARTMENT OF ENERGY SOIL AND GROUNDWATER SCIENCE AND TECHNOLOGY NEEDS, PLANS AND INITIATIVES

    Energy Technology Data Exchange (ETDEWEB)

    Aylward, B; V. ADAMS, V; G. M. CHAMBERLAIN, G; T. L. STEWART, T

    2007-12-12

    This paper presents the process used by the Department of Energy (DOE) Environmental Management (EM) Program to collect and prioritize DOE soil and groundwater site science and technology needs, develop and document strategic plans within the EM Engineering and Technology Roadmap, and establish specific program and project initiatives for inclusion in the EM Multi-Year Program Plan. The paper also presents brief summaries of the goals and objectives for the established soil and groundwater initiatives.

  1. The Soils and Groundwater – EM-20 S&T Roadmap Quality Assurance Project Plan

    Energy Technology Data Exchange (ETDEWEB)

    Fix, N. J.

    2008-02-11

    The Soils and Groundwater – EM-20 Science and Technology Roadmap Project is a U.S. Department of Energy, Office of Environmental Management-funded initiative designed to develop new methods, strategies and technology for characterizing, modeling, remediating, and monitoring soils and groundwater contaminated with metals, radionuclides, and chlorinated organics. This Quality Assurance Project Plan provides the quality assurance requirements and processes that will be followed by EM-20 Roadmap Project staff.

  2. Removal of Cu, Pb and Zn by foam fractionation and a soil washing process from contaminated industrial soils using soapberry-derived saponin: a comparative effectiveness assessment.

    Science.gov (United States)

    Maity, Jyoti Prakash; Huang, Yuh Ming; Hsu, Chun-Mei; Wu, Ching-I; Chen, Chien-Cheng; Li, Chun-Yi; Jean, Jiin-Shuh; Chang, Young-Fo; Chen, Chen-Yen

    2013-08-01

    The feasibility of using the eco-friendly biodegradable surfactant saponin (a plant-based surfactant) from soapberry and surfactin from Bacillus subtilis (BBK006) for the removal of heavy metals from contaminated industrial soil (6511mgkg(-1) copper, 4955mgkg(-1) lead, and 15090mgkg(-1) zinc) by foam fractionation and a soil flushing process was evaluated under variation of fundamental factors (surfactant concentration, pH, temperature and time). The results of latter process showed that 1-2% Pb, 16-17% Cu and 21-24% Zn was removed by surfactin after 48h, whereas the removal of Pb, Cu and Zn was increased from 40% to 47%, 30% to 36% and 16% to 18% in presence of saponin with an increase from 24 to 72h at room temperature by the soil washing process at pH 4. In the foam fractionation process, the metal removal efficiencies were increased with increases in the saponin concentration (0.075-0.15gL(-1)) and time (24-72h), whereas the efficiency was decreased with increasing pH (4-10) and temperature (>40°C). The removal efficiencies of Pb, Cu and Zn were increased significantly from 57% to 98%, 85% to 95% and 55% to 56% with an increase in the flow rate from 0.2 to 1.0Lmin(-1) at 0.15gL(-1) saponin (pH 4 and 30°C). The present investigation indicated that the foam fractionation process is more efficient for the removal of heavy metal from contaminated industrial soil in comparison to the soil washing process. The plant-based eco-friendly biodegradable biosurfactant saponin can be used for environmental cleanup and pollution management.

  3. Removal of arsenic and cadmium with sequential soil washing techniques using Na2EDTA, oxalic and phosphoric acid: Optimization conditions, removal effectiveness and ecological risks.

    Science.gov (United States)

    Wei, Meng; Chen, Jiajun; Wang, Xingwei

    2016-08-01

    Testing of sequential soil washing in triplicate using typical chelating agent (Na2EDTA), organic acid (oxalic acid) and inorganic weak acid (phosphoric acid) was conducted to remediate soil contaminated by heavy metals close to a mining area. The aim of the testing was to improve removal efficiency and reduce mobility of heavy metals. The sequential extraction procedure and further speciation analysis of heavy metals demonstrated that the primary components of arsenic and cadmium in the soil were residual As (O-As) and exchangeable fraction, which accounted for 60% and 70% of total arsenic and cadmium, respectively. It was determined that soil washing agents and their washing order were critical to removal efficiencies of metal fractions, metal bioavailability and potential mobility due to different levels of dissolution of residual fractions and inter-transformation of metal fractions. The optimal soil washing option for arsenic and cadmium was identified as phosphoric-oxalic acid-Na2EDTA sequence (POE) based on the high removal efficiency (41.9% for arsenic and 89.6% for cadmium) and the minimal harmful effects of the mobility and bioavailability of the remaining heavy metals.

  4. Groundwater.

    Science.gov (United States)

    Braids, Olin C.; Gillies, Nola P.

    1978-01-01

    Presents a literature review of groundwater quality covering publications of 1977. This review includes: (1) sources of groundwater contamination; and (2) management of groundwater. A list of 59 references is also presented. (HM)

  5. Monitoring the Perturbation of Soil and Groundwater Microbial Communities Due to Pig Production Activities

    KAUST Repository

    Hong, Pei-Ying

    2013-02-08

    This study aimed to determine if biotic contaminants originating from pig production farms are disseminated into soil and groundwater microbial communities. A spatial and temporal sampling of soil and groundwater in proximity to pig production farms was conducted, and quantitative PCR (Q-PCR) was utilized to determine the abundances of tetracycline resistance genes (i.e., tetQ and tetZ) and integrase genes (i.e., intI1 and intI2). We observed that the abundances of tetZ, tetQ, intI1, and intI2 in the soils increased at least 6-fold after manure application, and their abundances remained elevated above the background for up to 16 months. Q-PCR further determined total abundances of up to 5.88 × 109 copies/ng DNA for tetZ, tetQ, intI1, and intI2 in some of the groundwater wells that were situated next to the manure lagoon and in the facility well used to supply water for one of the farms. We further utilized 16S rRNA-based pyrosequencing to assess the microbial communities, and our comparative analyses suggest that most of the soil samples collected before and after manure application did not change significantly, sharing a high Bray-Curtis similarity of 78.5%. In contrast, an increase in Bacteroidetes and sulfur-oxidizing bacterial populations was observed in the groundwaters collected from lagoon-associated groundwater wells. Genera associated with opportunistic human and animal pathogens, such as Acinetobacter, Arcobacter, Yersinia, and Coxiella, were detected in some of the manure-treated soils and affected groundwater wells. Feces-associated bacteria such as Streptococcus, Erysipelothrix, and Bacteroides were detected in the manure, soil, and groundwater ecosystems, suggesting a perturbation of the soil and groundwater environments by invader species from pig production activities.

  6. Monitoring of Nitrate and Pesticide Pollution in Mnasra, Morocco Soil and Groundwater.

    Science.gov (United States)

    Marouane, Bouchra; Dahchour, Abdelmalek; Dousset, Sylvie; El Hajjaji, Souad

    2015-06-01

    This study evaluates the levels of nitrates and pesticides occurring in groundwater and agricultural soil in the Mnasra, Morocco area, a zone with intensive agricultural activity. A set of 108 water samples and 68 soil samples were collected from ten selected sites in the area during agricultural seasons, from May 2010 to September 2012. The results reveal that 89.7% of water samples exceeded the standard limit of nitrate concentrations for groundwater (50 mg/L). These results can be explained by the prevailing sandy nature of the soil in the area, the frequency of fertilizer usage, and the shallow level of the water table, which favors the leaching of nitrate from field to groundwater. In contrast, the selected pesticide molecules were not detected in the analysed soil and water samples; levels were below the quantification limit in all samples. This situation could be explained by the probable partial or total transformation of the molecules in soil.

  7. Effects of Soil and Water Conservation Measures on Groundwater Levels and Recharge

    Directory of Open Access Journals (Sweden)

    Hong Wang

    2014-12-01

    Full Text Available Measures of soil and water conservation (SWC could affect the hydrological process. The impacts of typical measures on groundwater recharge, levels and flow were analyzed based on simulated rainfall experiments and a groundwater model. The three-dimensional finite-difference groundwater flow model (MODFLOW was calibrated and verified for bare slope, grassland and straw mulching scenarios based on the experiments. The results of the verification in groundwater balance, levels, runoff and flow field all showed that MODFLOW could be applied to study the impact of SWC measures on groundwater. Meanwhile, the results showed the recharge rate (α and specific yield of the three soil layers (Sy1, Sy2 and Sy3 were the most sensitive parameters to the change in the underlying surface. Then, the impacts of the SWC measures’ construction and destruction on the groundwater regime were studied. The results indicated the measures could strengthen groundwater recharge. The amounts of groundwater recharge, runoff and level were on the order of straw mulching > grassland > bare slope. When the underlying surface was converted from grass and mulching to bare slope, the recharge decreased by 42.2% and 39.1%. It was concluded that SWC measure construction would increase groundwater recharge and the measure destruction would decrease recharge.

  8. Contributions of groundwater conditions to soil and water salinization

    Science.gov (United States)

    Salama, Ramsis B.; Otto, Claus J.; Fitzpatrick, Robert W.

    Salinization is the process whereby the concentration of dissolved salts in water and soil is increased due to natural or human-induced processes. Water is lost through one or any combination of four main mechanisms: evaporation, evapotranspiration, hydrolysis, and leakage between aquifers. Salinity increases from catchment divides to the valley floors and in the direction of groundwater flow. Salinization is explained by two main chemical models developed by the authors: weathering and deposition. These models are in agreement with the weathering and depositional geological processes that have formed soils and overburden in the catchments. Five soil-change processes in arid and semi-arid climates are associated with waterlogging and water. In all represented cases, groundwater is the main geological agent for transmitting, accumulating, and discharging salt. At a small catchment scale in South and Western Australia, water is lost through evapotranspiration and hydrolysis. Saline groundwater flows along the beds of the streams and is accumulated in paleochannels, which act as a salt repository, and finally discharges in lakes, where most of the saline groundwater is concentrated. In the hummocky terrains of the Northern Great Plains Region, Canada and USA, the localized recharge and discharge scenarios cause salinization to occur mainly in depressions, in conjunction with the formation of saline soils and seepages. On a regional scale within closed basins, this process can create playas or saline lakes. In the continental aquifers of the rift basins of Sudan, salinity increases along the groundwater flow path and forms a saline zone at the distal end. The saline zone in each rift forms a closed ridge, which coincides with the closed trough of the groundwater-level map. The saline body or bodies were formed by evaporation coupled with alkaline-earth carbonate precipitation and dissolution of capillary salts. Résumé La salinisation est le processus par lequel la

  9. Relationships between basic soils-engineering equations and basic ground-water flow equations

    Science.gov (United States)

    Jorgensen, Donald G.

    1980-01-01

    The many varied though related terms developed by ground-water hydrologists and by soils engineers are useful to each discipline, but their differences in terminology hinder the use of related information in interdisciplinary studies. Equations for the Terzaghi theory of consolidation and equations for ground-water flow are identical under specific conditions. A combination of the two sets of equations relates porosity to void ratio and relates the modulus of elasticity to the coefficient of compressibility, coefficient of volume compressibility, compression index, coefficient of consolidation, specific storage, and ultimate compaction. Also, transient ground-water flow is related to coefficient of consolidation, rate of soil compaction, and hydraulic conductivity. Examples show that soils-engineering data and concepts are useful to solution of problems in ground-water hydrology.

  10. Total petroleum hydrocarbon distribution in soils and groundwater in Songyuan oilfield, Northeast China.

    Science.gov (United States)

    Teng, Yanguo; Feng, Dan; Song, Liuting; Wang, Jinsheng; Li, Jian

    2013-11-01

    In order to investigate the distribution of the total petroleum hydrocarbons (TPH) in groundwater and soil, a total of 71 groundwater samples (26 unconfined groundwater samples, 37 confined groundwater samples, and 8 deeper confined groundwater samples) and 80 soil samples were collected in the Songyuan oilfield, Northeast China, and the vertical variation and spatial variability of TPH in groundwater and soil were assessed. For the groundwater from the unconfined aquifer, petroleum hydrocarbons were not detected in three samples, and for the other 23 samples, concentrations were in the range 0.01-1.74 mg/l. In the groundwater from the confined aquifer, petroleum hydrocarbons were not detected in two samples, and in the other 35 samples, the concentrations were 0.04-0.82 mg/l. The TPH concentration in unconfined aquifer may be influenced by polluted surface water and polluted soil; for confined aquifer, the injection wells leakage and left open hole wells may be mainly responsible for the pollution. For soils, the concentrations of TPH varied with sampling depth and were 0-15 cm (average concentration, 0.63 mg/g), >40-55 cm (average concentration, 0.36 mg/g), >100-115 cm (average concentration, 0.29 mg/g), and >500-515 cm (average concentration, 0.26 mg/g). The results showed that oil spillage and losses were possibly the main sources of TPH in soil. The consequences concluded here suggested that counter measures such as remediation and long-term monitoring should be commenced in the near future, and effective measures should be taken to assure that the oilfields area would not be a threat to human health.

  11. Greenhouse gas emission and groundwater pollution potentials of soils amended with different swine biochars

    Science.gov (United States)

    The objective of this research was to study the greenhouse gas emission and groundwater pollution potentials of the soils amended with various biochars using different biomass feedstocks and thermal processing conditions. Triplicate sets of small pots were designed; control soil consisting of Histi...

  12. Greenhouse gas emission and groundwater pollution potentials of soils amended with raw and carbonized swine solids

    Science.gov (United States)

    The objective of this research is to study the greenhouse gas emission and groundwater pollution potentials of the soils amended with raw swine solids and swine biochars made from different thermochemical conditions. Triplicate sets of small pots were designed: 1) control soil with a 50/50 mixture o...

  13. APPLICATION STRATEGIES AND DESIGN CRITERIA FOR IN SITU BIOREMEDIATION OF SOIL AND GROUNDWATER IMPACTED BY PAHS

    Science.gov (United States)

    Biotreatability studies conducted in our laboratory used soils from two former wood-treatment facilities to evaluate the use of in situ bioventing and biosparging applications for their potential ability to remediate soil and groundwater containing creosote. The combination of ph...

  14. SUPERFUND TREATABILITY CLEARINGHOUSE: CERCLA BDAT SARM PREPARATION AND RESULTS OF PHYSICAL SOILS WASHING EXPERIMENTS (FINAL REPORT)

    Science.gov (United States)

    This study reports on the results of work preparing 30,000 Ibs of SARM or synthetic analytical reference matrix, a surrogate Superfund soil containing a vide range of contaminants. It also reports the results ©f bench scale treatability experiments designed to simulate the EP...

  15. Scaling-up parameters for site restoration process using surfactant-enhanced soil washing coupled with wastewater treatment by Fenton and Fenton-like processes.

    Science.gov (United States)

    Bandala, Erick R; Cossio, Horacio; Sánchez-Lopez, Adriana D; Córdova, Felipe; Peralta-Herández, Juan M; Torres, Luis G

    2013-01-01

    Estimation of scaling-up parameters for a site restoration process using a surfactant-enhanced soil washing (SESW) process followed by the application of advanced oxidation processes (Fenton and photo-Fenton) was performed. For the SESW, different parameters were varied and the soil washing efficiency for pesticide (2,4-D) removal assessed. The resulting wastewater was treated using the Fenton reaction in the absence and presence of ultraviolet (UV) radiation for pesticide removal. Results showed that agitation speed of 1550 rpm was preferable for the best pesticide removal from contaminated soil. It was possible to wash contaminated soils with different soil concentrations; however the power drawn was higher as the soil concentration increased. Complete removal of the pesticide and the remaining surfactant was achieved using different reaction conditions. The best degradation conditions were for the photo-Fenton process using [Fe(II)] = 0.3 mM; [H2O2] = 4.0 mM where complete 2,4-D and sodium dodecylsulfate (SDS) removal was observed after 8 and 10 minutes of reaction, respectively. Further increase in the hydrogen peroxide or iron salt concentration did not show any improvement in the reaction rate. Kinetic parameters, i.e. reaction rate constant and scaling-up parameters, were determined. It was shown that, by coupling both processes (SESW and AOPs), it is possible the restoration of contaminated sites.

  16. Evaluation of soil washing process with carboxymethyl-β-cyclodextrin and carboxymethyl chitosan for recovery of PAHs/heavy metals/fluorine from metallurgic plant site.

    Science.gov (United States)

    Ye, Mao; Sun, Mingming; Kengara, Fredrick Orori; Wang, Jingting; Ni, Ni; Wang, Li; Song, Yang; Yang, Xinglun; Li, Huixin; Hu, Feng; Jiang, Xin

    2014-08-01

    Polycyclic aromatic hydrocarbons (PAHs)/heavy metals/fluorine (F) mixed-contaminated sites caused by abandoned metallurgic plants are receiving wide attention. To address the associated environmental problems, this study was initiated to investigate the feasibility of using carboxymethyl-β-cyclodextrin (CMCD) and carboxymethyl chitosan (CMC) solution to enhance ex situ soil washing for extracting mixed contaminants. Further, Tenax extraction method was combined with a first-three-compartment model to evaluate the environmental risk of residual PAHs in washed soil. In addition, the redistribution of heavy metals/F after decontamination was also estimated using a sequential extraction procedure. Three successive washing cycles using 50 g/L CMCD and 5 g/L CMC solution were effective to remove 94.3% of total PAHs, 93.2% of Pb, 85.8% of Cd, 93.4% of Cr, 83.2% of Ni and 97.3% of F simultaneously. After the 3rd washing, the residual PAHs mainly existed as very slowly desorbing fractions, which were in the form of well-aged, well-sequestered compounds; while the remaining Pb, Cd, Cr, Ni and F mainly existed as Fe-Mn oxide and residual fractions, which were always present in stable mineral forms or bound to non-labile soil fractions. Therefore, this combined cleanup strategy proved to be effective and environmentally friendly. Copyright © 2014. Published by Elsevier B.V.

  17. Daytime and nighttime groundwater contributions to soils with different surface conditions

    Science.gov (United States)

    Xing, Xuguang; Ma, Xiaoyi; Shi, Wenjuan

    2015-12-01

    Contributions of groundwater to the soil-water balance play an important role in areas with shallow water tables. The characteristics of daytime and nighttime water flux using non-weighing lysimeters were studied from June to September 2012 and 2013 in the extremely arid Xinjiang Uyghur Autonomous Region in northwestern China. The study consisted of nine treatments: three surface conditions, bare soil and cotton plants, each with water tables at depths of 1.0, 1.5, and 2.0 m; and plastic mulch with a water table at 1.5 m but with three percentages of open areas (POAs) in the plastic. The groundwater supply coefficient (SC) and the groundwater contribution (GC) generally varied with surface conditions. Both SC and GC decreased in the bare-soil and cotton treatments with increasing depth of the groundwater. Both SC and GC increased in the plastic-mulch treatment with increasing POA. Average nighttime GCs in the bare-soil treatments in July and August (the midsummer months) were 50.8-60.8 and 53.2-65.3 %, respectively, of the total daily contributions. Average nighttime GCs in the cotton treatments in July and August were 51.4-60.2 and 51.5-58.1 %, respectively, of the total daily contributions. The average GCs in June and September, however, were lower at night than during the daytime. Soil temperature may thus play a more important role than air temperature in the upflow of groundwater.

  18. The role of soil air composition for noble gas tracer applications in tropical groundwater

    Science.gov (United States)

    Mayer, Simon; Jenner, Florian; Aeschbach, Werner; Weissbach, Therese; Peregovich, Bernhard; Machado, Carlos

    2016-04-01

    Dissolved noble gases (NGs) in groundwater provide a well-established tool for paleo temperature reconstruction. However, reliable noble gas temperature (NGT) determination needs appropriate assumptions or rather an exact knowledge of soil air composition. Deviations of soil air NG partial pressures from atmospheric values have already been found in mid latitudes during summer time as a consequence of subsurface oxygen depletion. This effect depends on ambient temperature and humidity and is thus expected to be especially strong in humid tropical soils, which was not investigated so far. We therefore studied NGs in soil air and shallow groundwater near Santarém (Pará, Brazil) at the end of the rainy and dry seasons, respectively. Soil air data confirms a correlation between NG partial pressures, the sum value of O2+CO2 and soil moisture contents. During the rainy season, we find significant NG enhancements in soil air by up to 7% with respect to the atmosphere. This is twice as much as observed during the dry season. Groundwater samples show neon excess values between 15% and 120%. Nearly all wells show no seasonal variations of excess air, even though the local river level seasonally fluctuates by about 8 m. Assuming atmospheric NG contents in soil air, fitted NGTs underestimate the measured groundwater temperature by about 1-2° C. However, including enhanced soil air NG contents as observed during the rainy season, resulting NGTs are in good agreement with local groundwater temperatures. Our presented data allows for a better understanding of subsurface NG variations. This is essential with regard to NG tracer applications in humid tropical areas, for which reliable paleoclimate data is of major importance for modern climate research.

  19. Comparison of soil solution sampling techniques to assess metal fluxes from contaminated soil to groundwater.

    Science.gov (United States)

    Coutelot, F; Sappin-Didier, V; Keller, C; Atteia, O

    2014-12-01

    The unsaturated zone plays a major role in elemental fluxes in terrestrial ecosystems. A representative chemical analysis of soil pore water is required for the interpretation of soil chemical phenomena and particularly to assess Trace Elements (TEs) mobility. This requires an optimal sampling system to avoid modification of the extracted soil water chemistry and allow for an accurate estimation of solute fluxes. In this paper, the chemical composition of soil solutions sampled by Rhizon® samplers connected to a standard syringe was compared to two other types of suction probes (Rhizon® + vacuum tube and Rhizon® + diverted flow system). We investigated the effects of different vacuum application procedures on concentrations of spiked elements (Cr, As, Zn) mixed as powder into the first 20 cm of 100-cm columns and non-spiked elements (Ca, Na, Mg) concentrations in two types of columns (SiO2 sand and a mixture of kaolinite + SiO2 sand substrates). Rhizon® was installed at different depths. The metals concentrations showed that (i) in sand, peak concentrations cannot be correctly sampled, thus the flux cannot be estimated, and the errors can easily reach a factor 2; (ii) in sand + clay columns, peak concentrations were larger, indicating that they could be sampled but, due to sorption on clay, it was not possible to compare fluxes at different depths. The different samplers tested were not able to reflect the elemental flux to groundwater and, although the Rhizon® + syringe device was more accurate, the best solution remains to be the use of a lysimeter, whose bottom is kept continuously at a suction close to the one existing in the soil.

  20. Influence of long-term sewage irrigation on the distribution of organochlorine pesticides in soil-groundwater systems.

    Science.gov (United States)

    Zhang, Caixiang; Liao, Xiaoping; Li, Jiale; Xu, Liang; Liu, Ming; Du, Bin; Wang, Yanxin

    2013-07-01

    Serious shortage of water resources is one of the major factors restricting the sustainable development of cropland and pasture land in northern and northwestern China. Although the reuse of wastewater for agricultural irrigation becomes a well established practice in these regions, many contaminants have been also introduced into the soil-groundwater systems such as persistent organochlorine pesticides (OCPs). To study the influence of long-term sewage irrigation on the distribution of OCPs in soil-groundwater systems, the groundwater flow field was investigated and 31 topsoil samples, 9 boreholes, 11 sewage effluents and 34 groundwater samples were collected in Xiaodian, Taiyuan city, one of the largest sewage irrigation districts, China. During sampling, three representative types of regions were considered including effluent-irrigated area, groundwater-irrigated area served as the control field and no-irrigated area as reference "background". The results showed over-exploitation of groundwater had changed the flow field of groundwater and wherever in soil or in groundwater, the concentration of OCPs in effluent-irrigation area presented the highest value, which indicated that the sewage irrigation had a strong influence on the distribution of OCPs in soil-groundwater systems. Principal component analysis for OCPs content in groundwater showed that the major influence factors on the occurrence and distribution of OCPs in groundwater systems attribute to the flow field of groundwater and to the current pesticide use.

  1. Distribution of atrazine in a crop-soil-groundwater system at Baiyangdian Lake area in China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this paper, the concentration distribution and environmentalfate of atrazine in a crop-soil-groundwater system at Baiyangdian Lake area of North China were studied. The concentration of the herbicide in spatial and vertical soils, and in roots, stem, leaf, corncob and kernel of corn, and in groundwater were measured by HPLC. The results showed that the variation of spatial concentration of atrazine in soil can be described by first-order kinetics equation which has a half-life of 360 days and a rate constant of 0.0019d-1. The vertical variation of atrazine concentration with soil depth follows the exponential decay law. After 120 days following atrazine application, the mass distributions of this herbicide in crop-soil-groundwater system are 71% in soil, 20% in groundwater and 1% in crop respectively, and 8% due to loss by degradation or often removal processes. The order of atrazine concentration in every part of corn crop is in roots>in corncob>in kernel of corn>in leaf.

  2. An easily installable groundwater lysimeter to determine waterbalance components and hydraulic properties of peat soils

    Directory of Open Access Journals (Sweden)

    K. Schwaerzel

    2003-01-01

    Full Text Available A simple method for the installation of groundwater lysimeters in peat soils was developed which reduces both time and financial effort significantly. The method was applied on several sites in the Rhinluch, a fen peat land 60 km northwest of Berlin, Germany. Over a two-year period, upward capillary flow and evapotranspiration rates under grassland with different groundwater levels were measured. The installation of tensiometers and TDR probes additionally allowed the in situ determination of the soil hydraulic properties (water retention and unsaturated hydraulic conductivity. The results of the measurements of the unsaturated hydraulic conductivity demonstrate that more than one single method has to be applied if the whole range of the conductivity function from saturation to highly unsaturated is to be covered. Measuring the unsaturated conductivity can be done only in the lab for an adequately wide range of soil moisture conditions. Keywords: peat soils, soil hydraulic properties, evapotranspiration, capillary flow, root distribution, unsaturated zone

  3. Soil water, salt, and groundwater characteristics in shelterbelts with no irrigation for several years in an extremely arid area.

    Science.gov (United States)

    Zhao, Xinfeng; Xu, Hailiang; Zhang, Peng; Fu, Jinyi; Bai, Yuan

    2013-12-01

    This paper is based on long-term monitoring data for soil water, salt content, and groundwater characteristics taken from shelterbelts where there has been no irrigation for at least 5 years. This study investigated the distribution characteristics of soil water and salt content in soils with different textures. The relationships between soil moisture, soil salinity, and groundwater level were analyzed using 3 years of monitoring data from a typical oasis located in an extremely arid area in northwest China. The results showed that (1) the variation trend in soil moisture with soil depth in the shelterbelts varied depending on soil texture. The soil moisture was lower in sandy and loamy shelterbelts and higher in clay shelterbelts. (2) Salinity was higher (about 3.0 mS cm(-1)) in clay shelterbelts and lower (about 0.8 mS cm(-1)) in sandy shelterbelts. (3) There was a negative correlation between soil moisture in the shelterbelts and groundwater level. Soil moisture decreased gradually as the depth of groundwater table declined. (4) There was a positive correlation between soil salinity in the shelterbelts and the depth of groundwater table. Salinity increased gradually as groundwater levels declined.

  4. Influence of multi-step washing using Na2EDTA, oxalic acid and phosphoric acid on metal fractionation and spectroscopy characteristics from contaminated soil.

    Science.gov (United States)

    Wei, Meng; Chen, Jiajun

    2016-11-01

    A multi-step soil washing test using a typical chelating agent (Na2EDTA), organic acid (oxalic acid), and inorganic weak acid (phosphoric acid) was conducted to remediate soil contaminated with heavy metals near an arsenic mining area. The aim of the test was to improve the heavy metal removal efficiency and investigate its influence on metal fractionation and the spectroscopy characteristics of contaminated soil. The results indicated that the orders of the multi-step washing were critical for the removal efficiencies of the metal fractions, bioavailability, and potential mobility due to the different dissolution levels of mineral fractions and the inter-transformation of metal fractions by XRD and FT-IR spectral analyses. The optimal soil washing options were identified as the Na2EDTA-phosphoric-oxalic acid (EPO) and phosphoric-oxalic acid-Na2EDTA (POE) sequences because of their high removal efficiencies (approximately 45 % for arsenic and 88 % for cadmium) and the minimal harmful effects that were determined by the mobility and bioavailability of the remaining heavy metals based on the metal stability (I R ) and modified redistribution index ([Formula: see text]).

  5. Methodology of determining soil structure in important groundwater areas: case studies in Kauvonkangas, Finnish Lapland

    Science.gov (United States)

    Kupila, Juho

    2016-04-01

    Finland is fully self-sufficient in clean groundwater and even has a capacity of exportation. There are approx. 6000 groundwater areas with a total yield of 5.4 million m3/day. Currently only 10% of this groundwater resource is in use. For the efficient and safe exploitation of these areas in the future, detailed modeling of soil structure is an important method in groundwater surveys. 3D -models improve the general knowledge of linkage between land use planning and groundwater protection. Results can be used as a base information in water supply service development and when performing the measures needed in case of environmental accidents. Also, when creating the groundwater flow models the collected information is utilized and is usually the main data source. Geological Survey of Finland has carried out soil structure studies in co-operation with authorities, municipalities and the local water suppliers. The main objectives of these projects are to determine the geological structure of groundwater area for estimating the validity of the present exclusion area, the quantity of ground water volume and recharge capability and possible risks to the groundwater. Research areas are usually under an active water supply service. Kauvonkangas groundwater area is located in the municipality of Tervola, in Southern part of Finnish Lapland. Extent of the area is 7.9 km2 and it is an important water source for the local and nearby population centers. There are two active water supply companies in the area. Field studies in the project will include general geological and hydrological mapping, soil drilling with observation pipe installation, test pumping and water sampling. Geophysical measures will play a key-role, including ground penetrating radar (GPR) and gravimetric measurements. Studies will be carried out in spring and summer 2016. The main results will be the models of the bedrock and groundwater level and main characteristics of the soil layers in the area. Results

  6. Relations of As concentrations among groundwater, soil, and bedrock in Chungnam, Korea: implications for As mobilization in groundwater according to the As-hosting mineral change.

    Science.gov (United States)

    Kim, Kangjoo; Kim, Seok-Hwi; Jeong, Gi Young; Kim, Rak-Hyeon

    2012-01-15

    Arsenic (As) concentrations and As-bearing minerals in bedrock and soil, and their relations with groundwater concentrations were investigated in a small agricultural area of Korea. The As concentration of the bedrock shows a wide variation (<0.5-3990 mg/kg) and is well correlated with that in the contacting groundwaters (23-178 μg/L). Soils, the weathering product of bedrock, show the lower and more dispersed As concentrations (8.8-387 mg/kg) than the bedrock. But the soil As concentrations are very high relative to those reported from other areas. The As concentrations in the shallow groundwaters are comparatively low (<20 μg/L) and are independent of the soil concentration. Arsenopyrite is the major As-bearing mineral in the bedrock and its oxidation controls the As levels in deep groundwater. In contrast, As mostly resides in soil as Fe-(hydr)oxide-bound forms. Due to low pH and oxidizing redox condition, the release of As from Fe-(hydr)oxides is largely suppressed, and the shallow groundwater shows low As concentrations generally satisfying the drinking water limit. However, it is suggested that the disturbance of soil geochemical conditions by land use changes would cause a serious As contamination of the shallow groundwaters.

  7. Assessment of Soil Water Content in Field with Antecedent Precipitation Index and Groundwater Depth in the Yangtze River Estuary

    Institute of Scientific and Technical Information of China (English)

    XIE Wen-ping; YANG Jing-song

    2013-01-01

    To better understand soil moisture dynamics in the Yangtze River Estuary (YRE) and predict its variation in a simple way, a field monitoring experiment was carried out along the north branch of the Yangtze River, where seawater intrusion was strong and salt-water variation is one of the limiting factors of local agriculture. In present paper, relation between antecedent precipitation index (API) and soil water content is studied, and effects of groundwater depth on soil water content was analyzed. A relatively accurate prediction result of soil water content was reached using a neural network model. The impact analysis result showed that the variation of the API was consistent with soil water content and it displayed significant correlations with soil water content in both 20 and 50 cm soil layer, and higher correlation was observed in the layer of 20 cm. Groundwater impact analysis suggested that soil moisture was affected by the depth of groundwater, and was affected more greatly by groundwater at depth of 50 cm than that at 20 cm layer. By introducing API, groundwater depth and temperature together, a BP artificial network model was established to predict soil water content and an acceptable agreement was achieved. The model can be used for supplementing monitoring data of soil water content and predicting soil water content in shallow groundwater areas, and can provide favorable support for the research of water and salt transport in estuary area.

  8. Soil, Groundwater, Surface Water, and Sediments of Kennedy Space Center, Florida: Background Chemical and Physical Characteristics

    Science.gov (United States)

    Shmalzer, Paul A.; Hensley, Melissa A.; Mota, Mario; Hall, Carlton R.; Dunlevy, Colleen A.

    2000-01-01

    This study documented background chemical composition of soils, groundwater, surface; water, and sediments of Kennedy Space Center. Two hundred soil samples were collected, 20 each in 10 soil classes. Fifty-one groundwater wells were installed in 4 subaquifers of the Surficial Aquifer and sampled; there were 24 shallow, 16 intermediate, and 11 deep wells. Forty surface water and sediment samples were collected in major watershed basins. All samples were away from sites of known contamination. Samples were analyzed for organochlorine pesticides, aroclors, chlorinated herbicides, polycyclic aromatic hydrocarbons (PAH), total metals, and other parameters. All aroclors (6) were below detection in all media. Some organochlorine pesticides were detected at very low frequencies in soil, sediment, and surface water. Chlorinated herbicides were detected at very low frequencies in soil and sediments. PAH occurred in low frequencies in soiL, shallow groundwater, surface water, and sediments. Concentrations of some metals differed among soil classes, with subaquifers and depths, and among watershed basins for surface water but not sediments. Most of the variation in metal concentrations was natural, but agriculture had increased Cr, Cu, Mn, and Zn.

  9. Evaluation of soil temperature effect on herbicide leaching potential into groundwater in the Brazilian Cerrado.

    Science.gov (United States)

    Paraíba, Lourival Costa; Cerdeira, Antonio Luiz; da Silva, Enio Fraga; Martins, João Souza; Coutinho, Heitor Luiz da Costa

    2003-12-01

    The effect of annual variations in the daily average soil temperatures, at different depths, on the calculation of pesticide leaching potential indices is presented. This index can be applied to assess the risk of groundwater contamination by a pesticide. It considers the effects of water table depth, daily recharge net rate, pesticide sorption coefficient, and degradation rate of the pesticide in the soil. The leaching potential index is frequently used as a screening indicator in pesticide groundwater contamination studies, and the temperature effect involved in its calculation is usually not considered. It is well known that soil temperature affects pesticide degradation rates, air-water partition coefficient, and water-soil partition coefficient. These three parameters are components of the attenuation and retardation factors, as well as the leaching potential index, and contribute to determine pesticide behavior in the environment. The Arrhenius, van't Hoff, and Clausius-Clapeyron equations were used in this work to estimate the soil temperature effect on pesticide degradation rate, air-water partition coefficient, and water-soil partition coefficient, respectively. The relationship between leaching potential index and soil temperature at different depths is presented and aids in the understanding of how potential pesticide groundwater contamination varies on different climatic conditions. Numerical results will be presented for 31 herbicides known to be used in corn and soybean crops grown on the municipality of São Gabriel do Oeste, Mato Grosso do Sul State, Brazil.

  10. Exoenzyme activity in contaminated soils before and after soil washing: ß-glucosidase activity as a biological indicator of soil health.

    Science.gov (United States)

    Chae, Yooeun; Cui, Rongxue; Woong Kim, Shin; An, Gyeonghyeon; Jeong, Seung-Woo; An, Youn-Joo

    2017-01-01

    It is essential to remediate or amend soils contaminated with various heavy metals or pollutants so that the soils may be used again safely. Verifying that the remediated or amended soils meet soil quality standards is an important part of the process. We estimated the activity levels of eight soil exoenzymes (acid phosphatase, arylsulfatase, catalase, dehydrogenase, fluorescein diacetate hydrolase, protease, urease, and ß-glucosidase) in contaminated and remediated soils from two sites near a non-ferrous metal smelter, using colorimetric and titrimetric determination methods. Our results provided the levels of activity of soil exoenzymes that indicate soil health. Most enzymes showed lower activity levels in remediated soils than in contaminated soils, with the exception of protease and urease, which showed higher activity after remediation in some soils, perhaps due to the limited nutrients available in remediated soils. Soil exoenzymes showed significantly higher activity in soils from one of the sites than from the other, due to improper conditions at the second site, including high pH, poor nutrient levels, and a high proportion of sand in the latter soil. Principal component analysis revealed that ß-glucosidase was the best indicator of soil ecosystem health, among the enzymes evaluated. We recommend using ß-glucosidase enzyme activity as a prior indicator in estimating soil ecosystem health.

  11. Groundwater or floodwater? Assessing the pathways of metal exports from a coastal acid sulfate soil catchment.

    Science.gov (United States)

    Santos, Isaac R; de Weys, Jason; Eyre, Bradley D

    2011-11-15

    Daily observations of dissolved aluminum, iron, and manganese in an estuary downstream of a coastal acid sulfate soil (CASS) catchment provided insights into how floods and submarine groundwater discharge drive wetland metal exports. Extremely high Al, Fe, and Mn concentrations (up to 40, 374, and 8 mg L(-1), respectively) were found in shallow acidic groundwaters from the Tuckean Swamp, Australia. Significant correlations between radon (a natural groundwater tracer) and metals in surface waters revealed that metal loads were driven primarily by groundwater discharge. Dissolved Fe, Mn, and Al loads during a 16-day flood triggered by a 213 mm rain event were respectively 80, 35, and 14% of the total surface water exports during the four months of observations. Counter clockwise hysteresis was observed for Fe and Mn in surface waters during the flood due to delayed groundwater inputs. Groundwater-derived Fe fluxes into artificial drains were 1 order of magnitude higher than total surface water exports, which is consistent with the known accumulation of monosulfidic black ooze within the wetland drains. Upscaling the Tuckean catchment export estimates yielded dissolved Fe fluxes from global acid sulfate soil catchments on the same order of magnitude of global river inputs into estuaries.

  12. Characteristics and controls of variability in soil moisture and groundwater in a headwater catchment

    Science.gov (United States)

    McMillan, H. K.; Srinivasan, M. S.

    2015-04-01

    Hydrological processes, including runoff generation, depend on the distribution of water in a catchment, which varies in space and time. This paper presents experimental results from a headwater research catchment in New Zealand, where we made distributed measurements of streamflow, soil moisture and groundwater levels, sampling across a range of aspects, hillslope positions, distances from stream and depths. Our aim was to assess the controls, types and implications of spatial and temporal variability in soil moisture and groundwater tables. We found that temporal variability in soil moisture and water table is strongly controlled by the seasonal cycle in potential evapotranspiration, for both the mean and extremes of their distributions. Groundwater is a larger water storage component than soil moisture, and this general difference increases even more with increasing catchment wetness. The spatial standard deviation of both soil moisture and groundwater is larger in winter than in summer. It peaks during rainfall events due to partial saturation of the catchment, and also rises in spring as different locations dry out at different rates. The most important controls on spatial variability in storage are aspect and distance from the stream. South-facing and near-stream locations have higher water tables and showed soil moisture responses for more events. Typical hydrological models do not explicitly account for aspect, but our results suggest that it is an important factor in hillslope runoff generation. Co-measurement of soil moisture and water table level allowed us to identify relationships between the two. Locations where water tables peaked closer to the surface had consistently wetter soils and higher water tables. These wetter sites were the same across seasons. However, patterns of strong soil moisture responses to summer storms did not correspond to the wetter sites. Total catchment spatial variability is composed of multiple variability sources, and the

  13. Transient Soil Moisture Characteristics Below Different Land Cover Types: Implications for Quantifying Groundwater Recharge

    Science.gov (United States)

    Jayawickreme, D. H.; van Dam, R. L.; Hyndman, D. W.

    2006-12-01

    Statistical analysis of temporal water budgets in Michigan watersheds shows a significant link between land covers and streamflow characteristics. The observed differences in water budgets between the investigated watersheds are largely attributed to spatial heterogeneity and temporal variability of vegetation characteristics. Our findings suggest that management of regional groundwater resources should consider the effects of spatial and temporal vegetation changes. However, due to inadequate information, vegetation dynamics are not considered in most hydrologic models. By instrumenting suitable field sites in Michigan with different land cover types to monitor spatial and temporal variations in subsurface soil moisture , we investigate the interdependence of land cover, climate, soil moisture, and groundwater recharge in regional watersheds. Our approach involves resistivity and ground penetrating radar surveys, in-situ continuous moisture/temperature monitoring at field sites, and computer modeling of evapotranspiration and groundwater recharge. The results of this research are expected to improve our understanding of the impact of vegetation on soil moisture and groundwater recharge from site to regional scales and demonstrate the importance of incorporating land cover types and vegetation dynamics in regional groundwater resource assessment models.

  14. Screening Approach to the Activation of Soil and Contamination of Groundwater at Linear Proton Accelerator Sites

    CERN Document Server

    Otto, Thomas

    The activation of soil and the contamination of groundwater at proton accelerator sites with the radionuclides 3H and 22Na are estimated with a Monte-Carlo calculation and a conservative soil- and ground water model. The obtained radionuclide concentrations show that the underground environment of future accelerators must be adequately protected against a migration of activation products. This study is of particular importance for the proton driver accelerator in the planned EURISOL facility.

  15. Pore Pressure Response to Groundwater Fluctuations in Saturated Double-Layered Soil

    Directory of Open Access Journals (Sweden)

    Hongwei Ying

    2015-01-01

    Full Text Available Analytical solutions are developed for one-dimensional consolidation of double-layered saturated soil subjected to groundwater fluctuations. The solutions are derived by an explicit mathematical procedure using Duhamel’s theorem in conjunction with a Fourier series, when groundwater fluctuation is described by a general time-dependent function and assumed to be the pore water pressure variations at the upper boundary. Taking as an example the harmonic groundwater fluctuation, the relevant response of the excess pore water pressure is discussed in detail, and the main influencing factors of the excess pore pressure distribution are analyzed. A dimensionless parameter θ has been introduced because it significantly affects the phase and the amplitude of excess pore pressures. The influences of the coefficients of permeability and compressibility of soil on the excess pore pressure distribution are different and cannot be incorporated into the coefficient of consolidation in double-layered soil. The relative permeability ratio of two clayey soils also plays an important role on the curves of the distributions of the excess pore pressures. The effects of the thickness of the soil layer on the excess pore pressure distribution should be considered together with the dimensionless parameter θ and the permeability and compressibility of the double-layered soil system.

  16. Use of arsenic contaminated irrigation water for lettuce cropping: effects on soil, groundwater, and vegetal.

    Science.gov (United States)

    Beni, Claudio; Marconi, Simona; Boccia, Priscilla; Ciampa, Alessandra; Diana, Giampietro; Aromolo, Rita; Sturchio, Elena; Neri, Ulderico; Sequi, Paolo; Valentini, Massimiliano

    2011-10-01

    The present study investigated the effects of using arsenic (As) contaminated irrigation water in Lactuca sativa L. cropping. Two different arsenic concentrations, i.e., 25 and 85 μg L(-1) and two different soils, i.e., sandy and clay loam, were taken into account. We determined the arsenic mobility in the different soil fractions, its amount in groundwater, and the phytotoxicity and genotoxicity. Nuclear magnetic resonance (NMR) and inductively coupled plasma (ICP) were used to assess the lettuce metabolic profile changes and the arsenic uptake by the plant, respectively, as a function of the various conditions studied, i.e., As content and type of soil. Data indicated that at both concentrations in sandy soil, arsenic is in part quickly leached and thus present in groundwater and in part absorbed by the vegetable, being therefore readily available for assimilation by consumption. NMR results reported a large modification of the metabolic pattern, which was depending on the pollutant amount. In clay loam soil, the groundwater had a low As content with respect to sandy soil, and NMR and ICP performed on the lettuce did not reveal severe changes related to As, most likely because the metalloid is bound to the colloidal fraction.

  17. Groundwater recharge on east side soils of the Salinas Valley

    Science.gov (United States)

    After four years of drought, groundwater levels in the Salinas Valley are at historically low levels which threaten to adversely affect farming in the Salinas Valley. Given the prospect of a strong El Niño this coming winter, it seems prudent to plan to capture as much of the rainfall as possible to...

  18. 2-Phase groundwater and soil vapor extraction site test at McClellan AFB

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, C.; Kingsley, G.B.; Lawrence J. [Radian Corp., Sacramento, CA (United States)] [and others

    1995-09-01

    The innovative 2-phase extraction technique is a method recently patented by Xerox Corporation for simultaneously extracting contaminated groundwater and soil vapor from the subsurface. The 2-phase technique is primarily applicable to those sites with semipermeable soils containing volatile organic compound (VOC) contamination in both soils and groundwater. This technique has several distinct advantages over either conventional soil vapor extraction or groundwater extraction, because it can: cut the dollar per-contaminant-pound cleanup costs by an order of magnitude; simplify the extraction and treatment of both contaminated water and vapor; and shorten remediation times. The U.S. EPA and the Air Force elected to conduct an EPA Site test of the 2-phase Extraction technology at McClellan results indicate: The groundwater flow rate is twice that of the pump-and-treat system. The mass of contaminants from a single well removed increased from 130 lbs/year to more than 5,000 lbs/year, over 30 times more than the pump-and treat rate, with potential for even higher removal rates: 5,000 to 8,000 pounds of contaminants per year. Up to 95% of the contamination was extracted in the vapor phase, where it could be treated more easily and efficiently.

  19. Effect of harsh or mild extraction of soil on pesticide leaching to groundwater

    NARCIS (Netherlands)

    Boesten, Jos J.T.I.

    2016-01-01

    Assessment of leaching to groundwater is an important aspect of pesticide risk assessment. The first leaching tier usually consists of simulations with leaching scenarios based on pesticide- soil properties derived from laboratory studies. Because the extractability of pesticide residues in such

  20. Estimating groundwater evapotranspiration from irrigated cropland incorporating root zone soil texture and moisture dynamics

    Science.gov (United States)

    Wang, Xingwang; Huo, Zailin; Feng, Shaoyuan; Guo, Ping; Guan, Huade

    2016-12-01

    Estimating evapotranspiration from groundwater (ETg) is of importance to understanding water cycle and agricultural water management. Traditional ETg estimation was developed for regional steady condition and is difficult to be used for cropland where ETg changes with crop growth and irrigation schemes. In the present study, a new method estimating daily ETg during the crop growing season was developed. In this model, the effects of crop growth stage, climate condition, groundwater depth and soil moisture are considered. The method was tested with controlled lysimeter experiments of winter wheat including five controlled water table depths and four soil profiles of different textures. The simulated ETg is in good agreement with the measured data for four soil profiles and different depths to groundwater table. Coefficient of determination (R2) and coefficient of efficiency (NSE) are mostly larger than 0.85 and 0.70, respectively. This result suggests that the new method incorporating both soil texture and moisture dynamics can be used to estimate average daily groundwater evapotranspiration in cropland and contribute to quantifying the field water cycle.

  1. Groundwater pollution potential and greenhouse gas emission from soils amended with different swine biochars

    Science.gov (United States)

    Although there exist numerous research studies in the literature on greenhouse gas emission and groundwater pollution potentials of soils amended with plant-based biochar made from traditional dry pyrolysis (hereafter referred as pyrochar), a very few such studies exist for hydrochar made from hydro...

  2. Rapid nutrient leaching to groundwater and surface water in clay soil areas

    NARCIS (Netherlands)

    Bronswijk, J.J.B.; Hamminga, W.; Oostindie, K.

    1995-01-01

    The mechanism and magnitude of nitrate leaching from grassland on a heavy clay soil were investigated by measuring nitrogen input, and nitrate concentrations in groundwater and drain discharge for two years. A bromide tracer was applied to study solute transport mechanisms. Nitrate transport in the

  3. 羟基乙叉二膦酸对镉污染土壤的修复效果%Remediation of Cd Contaminated Soil by Washing with HEDP

    Institute of Scientific and Technical Information of China (English)

    孙秀菊; 崔爽; 李萍; 商丽艳; 张起凯; 陈建军; 刘艺芸

    2014-01-01

    为了探明 HEDP(羟基乙叉二膦酸)淋洗修复镉污染土壤的可行性,采用振荡提取和柱实验的方法,研究了 HEDP 不同浓度、土液比、淋洗时间和淋洗次数对土壤镉去除率的影响。结果表明:HEDP 浓度为3%、土液比为1∶3、淋洗时间为180 min、1次淋洗为镉污染土壤修复的最佳条件。可利用 HEDP 作为淋洗剂修复镉污染土壤。%In order to explore the washing feasibility of HEDP on remediation of Cd contaminated soil, batch and column experiments were conducted to investigate the removal rate of Cd in soil under various operating conditions,including HEDP concentration,ratio of soil to solution,leaching time and times. The results showed that the optimum conditions were as follows:HEDP concentration was 3%,the ratio of soil to solution was 1:3,leaching time was 180 min and leaching once can achieve the best removal rate of Cd,HEDP could be used in washing remediation of Cd contaminated soil.

  4. Compounding of a Combinable Surfactant for Oil-Contaminated Soil Washing%石油污染土壤淋洗配方的比选

    Institute of Scientific and Technical Information of China (English)

    李诗殷; 宁小兵; 蔡信德; 詹重贵

    2011-01-01

    This paper reports a lab-scaled experiment intended to develop an efficient surfactant for oil-contaminated soil remediation, focusing on selecting an optimal combinable surfactant formula. The washing of contaminated-soil packed in PVC colunms is conducted by solutions containing the suffactants, and an empirical model is employed to describe the oil desorption from the soil. The experiment indicates that the best compounding of suffactant as 5% of triton, 10% of sodium lignosulfonate, 42% sodium silicate, 43% of sodium carbonate, and oil-washing rate attains to 29.3% under the condition of continuous 96 hour washing and 0.4 mL/min of washing rate.%以广州市某废弃工业场地的石油污染土壤为研究对象,采用室内模拟试验的方法,考察了不同的pH、淋洗液配方、淋洗时间、以及土柱淋洗流量等因素对石油污染土壤淋洗修复效果的影响;并利用一级反应动力学模型对试验数据进行拟合.结果表明pH=8时水溶液对油的解吸量最大;最优淋洗液配方为5(曲拉通):10(本素钠):42(硅酸钠):43(碳酸钠).土柱淋洗效果与淋洗液使用量有较大关系,在0.40 mL/min用量时,96 h的除油率为29.3%,土壤中石油的含量由32 273 mg/kg下降至22 820 mg/kg.

  5. Assessment of groundwater and soil quality for agricultural purposes in Kopruoren basin, Kutahya, Turkey

    Science.gov (United States)

    Arslan, Sebnem

    2017-07-01

    This research evaluated the irrigation water and agricultural soil quality in the Kopruoren Basin by using hierarchical cluster analysis. Physico-chemical properties and major ion chemistry of 19 groundwater samples were used to determine the irrigation water quality indices. The results revealed out that the groundwaters are in general suitable for irrigation and have low sodium hazard, although they are very hard in nature due to the dominant presence of Ca+2, Mg+2 and HCO3- ions. Water samples contain arsenic in concentrations below the recommended guidelines for irrigation (59.7 ± 14.7 μg/l), however, arsenic concentrations in 89% of the 9 soil samples exceed the maximum allowable concentrations set for agricultural soils (81 ± 24.3 mg/kg). Nickel element, albeit not present in high concentrations in water samples, is enriched in all of the agricultural soil samples (390 ± 118.2 mg/kg). Hierarchical cluster analysis studies conducted to identify the sources of chemical constituents in water and soil samples elicited that the chemistry of the soils in the study area are highly impacted by the soil parent material and both geogenic and anthropogenic pollution sources are responsible for the metal contents of the soil samples. On the other hand, water chemistry in the area is affected by water-rock interactions, anthropogenic and agricultural pollution.

  6. Evaluation of B. subtilis SPB1 biosurfactants' potency for diesel-contaminated soil washing: optimization of oil desorption using Taguchi design.

    Science.gov (United States)

    Mnif, Inès; Sahnoun, Rihab; Ellouze-Chaabouni, Semia; Ghribi, Dhouha

    2014-01-01

    Low solubility of certain hydrophobic soil contaminants limits remediation process. Surface-active compounds can improve the solubility and removal of hydrophobic compounds from contaminated soils and, consequently, their biodegradation. Hence, this paper aims to study desorption efficiency of oil from soil of SPB1 lipopeptide biosurfactant. The effect of different physicochemical parameters on desorption potency was assessed. Taguchi experimental design method was applied in order to enhance the desorption capacity and establish the best washing parameters. Mobilization potency was compared to those of chemical surfactants under the newly defined conditions. Better desorption capacity was obtained using 0.1% biosurfacatnt solution and the mobilization potency shows great tolerance to acidic and alkaline pH values and salinity. Results show an optimum value of oil removal from diesel-contaminated soil of about 87%. The optimum washing conditions for surfactant solution volume, biosurfactant concentration, agitation speed, temperature, and time were found to be 12 ml/g of soil, 0.1% biosurfactant, 200 rpm, 30 °C, and 24 h, respectively. The obtained results were compared to those of SDS and Tween 80 at the optimal conditions described above, and the study reveals an effectiveness of SPB1 biosurfactant comparable to the reported chemical emulsifiers. (1) The obtained findings suggest (a) the competence of Bacillus subtilis biosurfactant in promoting diesel desorption from soil towards chemical surfactants and (b) the applicability of this method in decontaminating crude oil-contaminated soil and, therefore, improving bioavailability of hydrophobic compounds. (2) The obtained findings also suggest the adequacy of Taguchi design in promoting process efficiency. Our findings suggest that preoptimized desorption process using microbial-derived emulsifier can contribute significantly to enhancement of hydrophobic pollutants' bioavailability. This study can be

  7. Influence of soil on groundwater geochemistry in a carbonate aquifer, southern Italy

    Directory of Open Access Journals (Sweden)

    Tiziano Boschetti

    2014-01-01

    Full Text Available The role of soil compositions in influencing groundwater geochemistry in carbonate aquifers is still little known. Nothing is known regarding the influence of pyroclastic soils (andisol within the carbonate Apennines in central-southern Italy, despite their wide distribution. In this study we analyze some physical and chemical properties of pyroclastic soil at the Acqua dei Faggi experimental site (southern Italy, to assess its influence on groundwater geochemistry. Chemical analyses were carried out on saturated paste extracts and a physical analogue model was developed through two column experiments. Physico-chemical properties of rainwater and spring water, and some microbiological features of the soil medium were also taken into consideration. The studied soil has a great influence in modifying rainwater chemistry during percolation. About the 50% of HCO3- and Ca2+ in spring water is due to interaction between percolation water and soil medium, and equilibrium with calcite is reached at this stage. The Na+/K+ ratio is buffered by clay minerals in the soil by primary silicates in the pyroclastic cover and then buffered. Cl- and SO42- concentrations in spring water are very close to that of soil infiltration water during short-term interaction with soil, but a decline is showed during long-term cause to the anions adsorption effect in the andisol. Chemical and microbiological investigations show the existence of a soil microbial community that allows denitrification and nitrate reduction. Infiltration processes cause anoxic conditions within the soil medium, therefore the absence of NH4+ in spring water throughout the observation period should be due to anammox processes. These findings suggest that hydrochemistry and spring chemographs may be significantly influenced by several factors, such as relationships between soil and rainwater, vegetation, and microbial communities, which are not necessarily correlated with lithological and structural

  8. Radon occurrence in soil-gas and groundwater around an active landslide

    Energy Technology Data Exchange (ETDEWEB)

    Ramola, R.C. [Department of Physics, H.N.B. Garhwal University, Badshahi Thaul Campus, Tehri Garhwal -249 199 (India)], E-mail: rcramola@gmail.com; Choubey, V.M. [Wadia Institute of Himalayan Geology, Dehradun 248 001 (India); Negi, M.S.; Prasad, Yogesh; Prasad, Ganesh [Department of Physics, H.N.B. Garhwal University, Badshahi Thaul Campus, Tehri Garhwal -249 199 (India)

    2008-01-15

    This paper presents the results of investigation of radon levels in the soil-gas and groundwater of Uttarkashi, India within the distance of 5 km in vertical and horizontal directions from the landslide of Varunawat hill. Radon release from the soil and groundwater was found higher than the normal values. Radon concentration in groundwater over and around the landslide was found to vary from 0.51 to 86kBqm{sup -3}. The soil-gas radon concentration was found to vary from 219 to 3kBqm{sup -3} along the slope of landslide. Radon exhalation rate in collected soil samples was found to vary from 2.28x10{sup -5} to 9.01x10{sup -5}Bqkg{sup -1}h{sup -1}. Radon values were not found correlated with major and trace element contents in the upper soil of the area, which indicate that the migration of radon from deeper part of the earth along with landslide contribute to the surface radon concentration. Recorded values show a close association with local geology and Varunawat eruptions.

  9. Characterization and assessment of contaminated soil and groundwater at an organic chemical plant site in Chongqing, Southwest China.

    Science.gov (United States)

    Liu, Geng; Niu, Junjie; Zhang, Chao; Guo, Guanlin

    2016-04-01

    Contamination from organic chemical plants can cause serious pollution of soil and groundwater ecosystems. To characterize soil contamination and to evaluate the health risk posed by groundwater at a typical organic chemical plant site in Chongqing, China, 91 soil samples and seven groundwater samples were collected. The concentrations of different contaminants and their three-dimensional distribution were determined based on the 3D-krige method. Groundwater chemistry risk index (Chem RI) and cancer risk were calculated based on TRIAD and RBCA models. The chemistry risk indices of groundwater points SW5, SW18, SW22, SW39, SW52, SW80, and SW82 were 0.4209, 0.9972, 0.9324, 0.9990, 0.9991, 1.0000, and 1.0000, respectively, indicating that the groundwater has poor environmental status. By contrast, the reference Yangtse River water sample showed no pollution with a Chem RI of 0.1301. Benzene and 1,2-dichloroethane were the main contaminants in the groundwater and were responsible for the elevated cancer risk. The cumulative health risk of groundwater points (except SW5 and SW18) were all higher than the acceptable baselines of 10(-6), which indicates that the groundwater poses high cancer risk. Action is urgently required to control and remediate the risk for human health and groundwater ecosystems.

  10. Quantifying effects of soil heterogeneity on groundwater pollution at four sites in USA

    Institute of Scientific and Technical Information of China (English)

    Saskia Vuurens; Frank Stagnitti; Gerrit de Rooij; Jan Boll; LI Ling; Marc LeBlanc; Daniel lerodiaconou; Vince Versace; Scott Salzman

    2005-01-01

    Four sites located in the north-eastern region of the United States of America have been chosen to investigate the impacts of soil heterogeneity in the transport of solutes (bromide and chloride) through the vadose zone (the zone in the soil that lies below the root zone and above the permanent saturated groundwater). A recently proposed mathematical model based on the cumulative beta distribution has been deployed to compare and contrast the regions' heterogeneity from multiple sample percolation experiments. Significant differences in patterns of solute leaching were observed even over a small spatial scale, indicating that traditional sampling methods for solute transport, for example the gravity pan or suction lysimeters, or more recent inventions such as the multiple sample percolation systems may not be effective in estimating solute fluxes in soils when a significant degree of soil heterogeneity is present. Consequently, ignoring soil heterogeneity in solute transport studies will likely result in under- or overprediction of leached fluxes and potentially lead to serious pollution of soils and/or groundwater.The cumulative beta distribution technique is found to be a versatile and simple technique of gaining valuable information regarding soil heterogeneity effects on solute transport. It is also an excellent tool for guiding future decisions of experimental designs particularly in regard to the number of samples within one site and the number of sampling locations between sites required to obtain a representative estimate of field solute or drainage flux.

  11. Interactions among Climate Forcing, Soil Water, and Groundwater for Enhanced Water Management Practices in Nebraska

    Science.gov (United States)

    You, J.; Hubbard, K. G.; Chen, X.

    2009-12-01

    Water is one of the most valuable and vulnerable resources. The varying precipitation regimes together with the varying land use and land cover types over the state of Nebraska necessitate continuous monitoring and modeling of soil water, particularly in the root zone. Underlying the irrigated lands is the High Plains Aquifer, one of the largest in the world. The Ogallala Aquifer is hydrologically connected with streams in numerous river valleys and with rainfall/soil water at the surface. To sustain water reserves the net effect of groundwater pumping for irrigation and recharging the ground water system by precipitation/irrigation. If the net effect is zero or positive the reserves will not shrink. The Automated Weather Data Network (AWDN) of Nebraska has intensive soil water observation and critical weather measurements. Nebraska also has ground water wells, co-located with or near some of the AWDN stations. This work was conducted to continuously monitor the soil water and groundwater table and to model the surface and subsurface hydrologic processes as an integrated/linked system. The further task is to quantify the recharge under different initial conditions, land use practices, and to combine the new information with a surface hydrology model over various sites in Nebraska. To accomplish these objectives two weather stations were installed and enhanced at Shelton and Kearney and soil probes were buried directly under the crop lands. The newly installed soil water probes are co-located with the nearby weather stations and ground water wells. All the data recorded from the atmosphere, soil and aquifer will be incorporated into AWDN data archives and will be analyzed to examine the interactions between precipitation, soil moisture and groundwater.

  12. PIMS:Remediation of Soil and Groundwater Contaminated With Metals

    Science.gov (United States)

    2006-06-01

    covering the amended soils with a layer of uncontaminated surface soil, and seeding with native grasses and wildflowers . Shallow lysimeter monitoring... wildflowers and grasses. Shallow lysimeter wells were installed at three positions around the site to collect leachate leaving the treatment zone...Priority Pollutants Laboratory, Inc. (APPL) in Fresno, California . This page left blank intentionally. 17 4.0 PERFORMANCE ASSESSMENT 4.1

  13. A new separation and treatment method for soil and groundwater restoration

    Energy Technology Data Exchange (ETDEWEB)

    Hitchens, G.D. [Lynntech, Inc., College Station, TX (United States)

    1997-10-01

    Soil and groundwater contamination by organic compounds is a widespread environmental pollution problem. In many cases, contaminated soil is excavated and transported to a landfill or is incinerated to remove contaminants. These remediation practices are expensive, environmentally disruptive, require extensive permitting, and only move contamination from one location to another. Onsite and in situ treatment techniques offer a safer, more cost-effective, and permanent solution. Many soil and groundwater contaminants are highly volatile, enabling the use of methods such as in situ vacuum extraction and air injection for their removal. However, these methods are often difficult to use because of slow volatilization rates and the lack of effective methods to treat the extracted hazardous material. This Phase I Small Business Innovation Research program focuses on developing an in situ soil and groundwater remediation technique that is effective against volatile as well as nonvolatile compounds and that will shorten treatment times. The technique forms the basis of a new catalytic process to degrade extracted contaminants onsite. Key hardware elements on which the new technique is based have been proven in preliminary research. The method has a high potential for public and regulatory acceptance because of its low environment impact.

  14. Monitoring the risk of nitrate and pesticides Pollution in Mnasra groundwater and soil under Field Condition-Morocco

    Science.gov (United States)

    El hajjaji, Souad; Dahchour, abdelmalek

    2017-04-01

    Agricultural activities are probably the most significant anthropogenic sources of nitrate an pesticides contamination in groundwater and soil. Irrigation system is among the causes behind leaching of nitrate and pesticides from soil surface to groundwater. Gharb plain is the largest agriculture irrigated zone in northwest of Morocco, well known for its intensive agricultural activities. The excessive use of fertilizers and manure under gravity irrigation system, presents a huge risk to groundwater quality especially for sandy-loam soils similar to those of the area. The purpose of the present study was the evaluation of the level of nitrate and pesticides contamination in groundwater and soil, and the attempt to relate it to the irrigation system adopted in Gharb area. A set of 108 water samples and 60 soil samples were collected from ten selected sites located in the area during agricultural seasons, from May 2010 to September 2012. The results reveal that 89.7% of water samples exceeded the standard limit of nitrate concentrations for groundwater (50 mg/L). These results could be explained by the prevailing sandy nature of the soil in the area, the frequency of fertilizer usage, and the shallow level of the water table, which favors the leaching of nitrate from field to groundwater. In contrast, the selected pesticide molecules were not detected in the analyzed soil and water samples; levels were below the quantification limit in all samples.). Attempts to focus on the main physical and chemical factors behind the magnitude of contamination are discussed

  15. Monitoring the Remediation of Salt-Affected Soils and Groundwater

    Science.gov (United States)

    Bentley, L. R.; Callaghan, M. V.; Cey, E. E.

    2008-12-01

    Salt-affected soil is one of the most common environmental issues facing the petroleum hydrocarbon industry. Large quantities of brines are often co-produced with gas and oil and have been introduced into the environment through, for example, flare pits, drilling operations and pipe line breaks. Salt must be flushed from the soil and tile drain systems can be used to collect salt water which is then be routed for disposal. A flushing experiment over a 2 m deep tile drain system is being monitored by arrays of tensiometers, repeated soil coring, direct push electrical conductivity profiles (PTC), electromagnetic surveys and electrical resistivity tomography (ERT) surveys. Water table elevation is monitored with pressure transducers. Thermocouple arrays provide temperature profiles that are used to adjust electrical conductivity data to standard temperature equivalents. A 20 m by 20 m plot was deep tilled and treated with soil amendments. Numerous infiltration tests were conducted inside and outside the plot area using both a tension infiltrometer and Guelph permeameter to establish changes in soil hydraulic properties and macroporosity as a result of deep tillage. The results show that till greatly diminished the shallow macroporosity and increased the matrix saturated hydraulic conductivity. A header system is used to evenly flood the plot with 10 m3 of water on each of three consecutive days for an approximate total of 7.5 cm of water. The flood event is being repeated four times over a period of 6 weeks. Baseline PTC and ERT surveys show that the salt is concentrated in the upper 2 to 3 m of soil. Tensiometer data show that the soil at 30 cm depth responds within 2 to 3 hours to flooding events once the soil is wetted and begins to dry again after one week. Soil suction at 1.5 m does not show immediate response to the daily flooding events, but is steadily decreasing in response to the flooding and rainfall events. An ERT survey in October will provide the first

  16. Fiscal Year 2009 Annual Report for Operable Unit 3-14, Tank Farm Soil and INTEC Groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Forsythe, Howard S.

    2010-04-10

    This annual report summarizes maintenance, monitoring, and inspection activities performed to implement the selected remedy for Waste Area Group 3, Operable Unit 3-14, Tank Farm soil and groundwater at the Idaho Nuclear Technology and Engineering Center located within the Idaho National Laboratory Site. Results from monitoring perched water and groundwater at the Idaho Nuclear Technology and Engineering Center are also presented.

  17. Shallow groundwater effect on land surface temperature and surface energy balance under bare soil conditions: modeling and description

    Directory of Open Access Journals (Sweden)

    F. Alkhaier

    2012-07-01

    Full Text Available Understanding when and how groundwater affects surface temperature and energy fluxes is significant for utilizing remote sensing in groundwater studies and for integrating aquifers within land surface models. To investigate the shallow groundwater effect under bare soil conditions, we numerically exposed two soil profiles to identical metrological forcing. One of the profiles had shallow groundwater. The different responses that the two profiles manifested were inspected regarding soil moisture, temperature and energy balance at the land surface. The findings showed that the two profiles differed in three aspects: the absorbed and emitted amounts of energy, the portioning out of the available energy and the heat fluency in the soil. We concluded that due to their lower albedo, shallow groundwater areas reflect less shortwave radiation and consequently get a higher magnitude of net radiation. When potential evaporation demand is sufficiently high, a large portion of the energy received by these areas is consumed for evaporation. This increases the latent heat flux and reduces the energy that could have heated the soil. Consequently, lower magnitudes of both sensible and ground heat fluxes are caused to occur. The higher soil thermal conductivity in shallow groundwater areas facilitates heat transfer between the top soil and the subsurface, i.e. soil subsurface is more thermally connected to the atmosphere. For the reliability of remote sensors in detecting shallow groundwater effect, it was concluded that this effect can be sufficiently clear to be detected if at least one of the following conditions occurs: high potential evaporation and high contrast between day and night temperatures. Under these conditions, most day and night hours are suitable for shallow groundwater depth detection.

  18. Assessing soil and groundwater contamination from biofuel spills.

    Science.gov (United States)

    Chen, Colin S; Shu, Youn-Yuen; Wu, Suh-Huey; Tien, Chien-Jung

    2015-03-01

    Future modifications of fuels should include evaluation of the proposed constituents for their potential to damage environmental resources such as the subsurface environment. Batch and column experiments were designed to simulate biofuel spills in the subsurface environment and to evaluate the sorption and desorption behavior of target fuel constituents (i.e., monoaromatic and polyaromatic hydrocarbons) in soil. The extent and reversibility of the sorption of aromatic biofuel constituents onto soil were determined. When the ethanol content in ethanol-blended gasoline exceeded 25%, enhanced desorption of the aromatic constituents to water was observed. However, when biodiesel was added to diesel fuel, the sorption of target compounds was not affected. In addition, when the organic carbon content of the soil was higher, the desorption of target compounds into water was lower. The empirical relationships between the organic-carbon normalized sorption coefficient (Koc) and water solubility and between Koc and the octanol-water partition coefficient (Kow) were established. Column experiments were carried out for the comparison of column effluent concentration/mass from biofuel-contaminated soil. The dissolution of target components depended on chemical properties such as the hydrophobicity and total mass of biofuel. This study provides a basis for predicting the fate and transport of hydrophobic organic compounds in the event of a biofuel spill. The spill scenarios generated can assist in the assessment of biofuel-contaminated sites.

  19. Assessment of environmental degradation of soil and groundwater ...

    African Journals Online (AJOL)

    Guest

    Moat, case of environmental toxicity. ... 36′ 00″) E in Egor-Oredo local government area of Benin City, covering an ... present work and those of Akujieze (2004) and Akujieze and Oteze. (2007) ..... and the redox status of contaminated soils.

  20. Biodegradation of cyanide in groundwater and soils from gasworks sites in south-eastern Australia

    Energy Technology Data Exchange (ETDEWEB)

    Meehan, S.M.E.; Weaver, T.R.; Lawrence, C.R. [University of Melbourne, Parkvills, Vic. (Australia). School of Earth Sciences

    1999-07-01

    Groundwater from a gasworks site in south-eastern Australia has been found to contain high concentrations of cyanide (total), sulphate, and ammonia (1400 mg L{sup -1}, 6500 mg L{sup -1}, and 580 mg L{sup -1} respectively). Soil from another gasworks site has been found to contain 587 mg kg{sup -1} of cyanide (total), with concentrations of cyanide in the groundwater at this site being relatively low ({lt} 21 mgL{sup -1} CN(Total)). Experiments were conducted to determine the biodegradation rates of cyanide in groundwater and soils using samples from both sites. Column experiments and bioreactors were constructed to produce both aerobic and anaerobic conditions for the groundwater containing high concentrations of cyanide. Samples of water were taken periodically to analyse the pH, redox potential, temperature, and concentrations of cyanide (free and total), sulphate, ammonia, nitrate and dissolved organic carbon (DOC). Initial results indicate that concentrations of cyanide are declining in both aerobic and anaerobic conditions, with biodegradation one process producing degradation. 9 refs., 4 figs., 2 tabs.

  1. Endosulfan sulfate mobility in soil columns and pesticide pollution of groundwater in Northwest Morocco.

    Science.gov (United States)

    El Bakouri, Hicham; Ouassini, Abdelhamid; Morillo Aguado, José; Usero García, José

    2007-12-01

    Groundwater pollution from agricultural practices is a serious environmental and health problem. In this work, stir bar sorptive extraction (SBSE) and gas chromatography (GC) with mass spectrometry (MS) detection were used to determine phytosanitary products in groundwater samples from the Loukkos perimeter in Northwest Morocco. Some pesticides--in particular, endosulfan and its metabolites--were found in water destined for human consumption. Analyses of soil samples were also carried out, and the results showed endosulfan sulfate and endosulfan ether in abundance. Endosulfan sulfate leaching was also performed in undisturbed soil columns to obtain more information on the vertical migration of pesticides used in the perimeter. The kinetic study showed a high recovery rate (73%) after 10 days of experimental work.

  2. Spray washing, absorbent corn starch powder and dry time to reduce bacterial numbers on soiled boiler transport cage flooring

    Science.gov (United States)

    Most broilers in the U.S. are transported live to slaughter facilities in cages with fiberglass floors. Cages are often used repeatedly without washing and fecal matter deposited on the floor surface can transfer Campylobacter from one flock to another. Drying feces out between uses is an effectiv...

  3. Screening-Level Risk Assessment for Styrene-Acrylonitrile (SAN) Trimer Detected in Soil and Groundwater

    OpenAIRE

    Kirman, C. R.; Gargas, M L; Collins, J. J.; Rowlands, J. C.

    2012-01-01

    A screening-level risk assessment was conducted for styrene-acrylonitrile (SAN) Trimer detected at the Reich Farm Superfund site in Toms River, NJ. Consistent with a screening-level approach, on-site and off-site exposure scenarios were evaluated using assumptions that are expected to overestimate actual exposures and hazards at the site. Environmental sampling data collected for soil and groundwater were used to estimate exposure point concentrations. Several exposure scenarios were evaluate...

  4. groundwater contribution to crop water requirement groundwater ...

    African Journals Online (AJOL)

    eobe

    Keywords: Groundwater, water table, capillary rise, soil type, waterleaf, ... GROUNDWATER CONTRIBUTION TO WATERLEAF (TALINUM TRIANGULARE) IN OXISOLS, I. J. ... Nutritionally, ... information to facilitate increased crop production,.

  5. Uncertainty of Coupled Soil-Vegetation-Atmosphere Modelling Methods for Estimating Groundwater Recharge

    Science.gov (United States)

    Xie, Y.; Cook, P. G.; Simmons, C. T.; Partington, D.; Crosbie, R.; Batelaan, O.

    2016-12-01

    Coupled soil-vegetation-atmosphere models have become increasingly popular for estimating groundwater recharge, because of the integration of carbon, energy and water balances. The carbon and energy balances act to constrain the water balance and as a result should reduce the uncertainty of groundwater recharge estimates. However, the addition of carbon and energy balances also introduces a large number of plant physiological parameters which complicates the estimation of groundwater recharge. Moreover, this method often relies on existing pedotransfer functions to derive soil water retention curve parameters and saturated hydraulic conductivity from soil attribute data. The choice of a pedotransfer function is usually subjective and several pedotransfer functions may be fit for the purpose. These different pedotransfer functions (and thus the uncertainty of soil water retention curve parameters and saturated hydraulic conductivity) are likely to increase the prediction uncertainty of recharge estimates. In this study, we aim to assess the potential uncertainty of groundwater recharge when using a coupled soil-vegetation-atmosphere modelling method. The widely used WAter Vegetation Energy and Solute (WAVES) modelling code was used to perform simulations of different water balances in order to estimate groundwater recharge in the Campaspe catchment in southeast Australia. We carefully determined the ranges of the vegetation parameters based upon a literature review. We also assessed a number of existing pedotransfer functions and selected the four most appropriate. Then the Monte Carlo analysis approach was employed to examine potential uncertainties introduced by different types of errors. Preliminary results suggest that for a mean rainfall of about 500 mm/y and annual pasture vegetation, the estimated recharge may range from 10 to 150 mm/y due to the uncertainty in vegetation parameters. This upper bound of the recharge range may double to 300 mm/y if different

  6. Contamination of soils and groundwater with new organic micropollutants: A review

    Science.gov (United States)

    Vodyanitskii, Yu. N.; Yakovlev, A. S.

    2016-05-01

    The input of organic micro- and nanopollutants to the environment has grown in recent years. This vast class of substances is referred to as emerging micropollutants, and includes organic chemicals of industrial, agricultural, and municipal provenance. There are three main sources of emerging pollutants coming to the environment, i.e., (1) upon soil fertilization with sewage and sewage sludge; (2) soil irrigation with reclaimed wastewater and (3) due to filtration from municipal landfills of solid wastes. These pollutants contaminate soil, affect its inhabitants; they are also consumed by plants and penetrate to the groundwater. The pharmaceuticals most strongly affect the biota (microorganisms, earthworms, etc.). The response of microorganisms in the contaminated soil is controlled not only by the composition and the number of emerging pollutants but also by the geochemical environment.

  7. Random Boundary Simulation of Pumping Groundwater on Two-layer Soft Soil Structure with Porous Media

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Based on random theory,fluid dynamics,porous media and soil mechanics,the porosity and random characteristic of the two-layer soft soil in Wuhan region were studied in this paper.The random seepage coefficient on the two-layer soft soil was analyzed,and the seepage model and its random distribution function were given.The groundwater flow differential equations related to the two layer soft soil structure were also established.The evaluation procedure of effect boundary on the pumping water in deep foundation pit was put forward.Moreover,with an engineering example,the probability distribution on random boundary prediction for pumping water of foundation pit was computed.

  8. Groundwater Availability Alters Soil-plant Nutrient Cycling in a Stand of Invasive, N-fixing Phreatophytes

    Science.gov (United States)

    Dudley, B. D.; Miyazawa, Y.; Hughes, F.; Ostertag, R.; Kettwich, S. K.; MacKenzie, R.; Dulaiova, H.; Waters, C. A.; Bishop, J.; Giambelluca, T. W.

    2013-12-01

    N-fixing phreatophytic trees are common in arid and semi-arid regions worldwide, and can play significant roles in modifying hydrology and soil-plant nutrient cycling where they are present. In light of reductions in groundwater levels in many arid regions we estimated annual transpiration rates at a stand level, and alterations to C, N and P accretion in soils as a function of groundwater depth in a ca.120 year old stand of Prosopis pallida along an elevation gradient in coastal leeward Hawaii. We measured sapflow and stand level sapwood area to quantify transpiration, and calculated groundwater transpiration rates using P. pallida stem water δ18O values. By measuring soil resistivity, we were able to compare the volume of groundwater transpired by these trees to groundwater depth across the stand. We examined nutrient deposition and accretion in soils in lowland areas of the stand with accessible shallow groundwater, compared to upland areas with no groundwater access, as indicated by stem water δ18O values. Resistivity results suggested that groundwater was at a height close to sea level throughout the stand. Transpiration was around 1900 m3 ha-1 year-1 in the areas of the stand closest to the sea (where groundwater was at around 1-4 m below ground level) and decreased to around a tenth of that volume where groundwater was not accessible. Litterfall rates over the course of the year studied were 17 times greater at lowland sites, but this litterfall contributed ca. 24 times the N, and 35 times the P of upland sites. Thus, groundwater access contributed to the total mass of nitrogen and phosphorus deposited in the form of litter through higher litter quantity and quality. Total N content of soils was 4.7 times greater and inorganic N pools were eight times higher at lowland plots. These results suggest that groundwater depth can have strong effects on soil-plant nutrient cycling, so that reductions in the availability of shallow groundwater are likely to impact

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

    Science.gov (United States)

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

    2014-03-01

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

  10. Shallow groundwater effect on land surface temperature and surface energy balance under bare soil conditions: modeling and description

    Directory of Open Access Journals (Sweden)

    F. Alkhaier

    2011-09-01

    Full Text Available Appreciating when and how groundwater affects surface temperature and energy fluxes is important for utilizing remote sensing in groundwater studies and for integrating aquifers within land surface models. To explore the shallow groundwater effect, we numerically exposed two soil profiles – one having shallow groundwater – to the same meteorological forcing, and inspected their different responses regarding surface soil moisture, temperature and energy balance. We found that the two profiles differed in the absorbed and emitted amounts of energy, in portioning out the available energy and in heat fluency within the soil. We conclude that shallow groundwater areas reflect less shortwave radiation due to their lower albedo and therefore they get higher magnitude of net radiation. When potential evaporation demand is high enough, a large portion of the energy received by these areas is spent on evaporation. This makes the latent heat flux predominant, and leaves less energy to heat the soil. Consequently, this induces lower magnitudes of both sensible and ground heat fluxes. The higher soil thermal conductivity in shallow groundwater areas facilitates heat transfer between the top soil and the subsurface, i.e. soil subsurface is more thermally connected to the atmosphere. In view of remote sensors' capability of detecting shallow groundwater effect, we conclude that this effect can be sufficiently clear to be sensed if at least one of two conditions is met: high potential evaporation and big contrast in air temperature between day and night. Under these conditions, most day and night hours are suitable for shallow groundwater depth detection.

  11. Biosolids and distillery effluent amendment to Irish Miscanthus ×giganteus plantations: impacts on groundwater and soil.

    Science.gov (United States)

    Galbally, P; Fagan, C; Ryan, D; Finnan, J; Grant, J; McDonnell, K

    2012-01-01

    It is necessary to determine the risk of water pollution arising from amendment of organic by-products (OBs) to energy crops under Irish conditions. Therefore, the impact of landspreading two OBs on the quality of groundwater underlying plantations of Miscanthus X giganteus was assessed. Municipal biosolids and distillery effluent (DE) were spread annually (for 4 yr) on six 0.117-ha treatment plots at rates of 100, 50, and 0%. The 100% rate represented a maximum P load of 15 t ha(-1) as per Irish EPA regulation. Groundwater was sampled for 25 mo and tested for pH, electrical conductivity, NO(3)(-), orthophosphate (PO(4)(3-)), total soluble P, K(+), Cu, Cd, Cr, Pb, Ni, and Zn. Assessment of quality was based on comparison with Irish groundwater threshold values (GTVs). The study was limited to within-plot using a "well bottom" approach and did not investigate movement of groundwater plumes or vectors of percolation through the soil profile. Mean groundwater concentrations did not exceed GTVs during the sampling period for any species, with the exception of groundwater PO(4)(3-) in the 100% DE plot, which was almost double the GTV of 0.035 mg L(-1). There was no significant build-up of nutrients or heavy metals in groundwater (or soil) for any plot. Excessive PO(4)(3-) in the 100% DE plot groundwater is likely due to high background soil P, soil characteristics, and the occurrence of macropore/soil pore flow. These factors (particularly background soil P) should be assessed when determining suitable sites for land-spreading OBs. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. Arsenic contamination in shallow groundwater and agricultural soil of Chakdaha Block, West Bengal, India

    Directory of Open Access Journals (Sweden)

    Anamika eShrivastava

    2014-11-01

    Full Text Available The study area comes in one of the eight districts of West Bengal where groundwater contains arsenic above the prescribed limit by WHO (10μg/l. Each day groundwater is being withdrawn by the village people for the fulfillment of their basic needs and for agricultural purposes. With the groundwater along with high concentration of arsenic (As, many other heavy metals are also getting introduced in the environment. In the areas with a long history of use of such groundwater, the agricultural lands have been affected severely. The extent of contamination has increased to a level where the crops grown in those lands are becoming a major source for arsenic and other heavy metals poisoning and subsequently transfer to different trophic levels. Based on this concern a somewhat detailed study was carried out to obtain an idea about the magnitude of soil and water contamination in the area. The mean concentrations (mg/kg of As (9.67, Fe (9275.58, Mn (190.04, Cu (26.53 and Zn (36.04 in the control land soils were found within the normal range. Whereas the mean As (54.40, Fe (15745.50, Mn (307.90, Cu (69.33 and Zn (44.56 were found to be in higher, mainly arsenic which is at an alarming point. In case of water samples, the pond water was having the mean concentration (μg/l of As (32.63, Fe (57.21, Mn (30.25, Cu (0.82. Whereas in case of shallow groundwater there was more increase in the case of As (76.43, Fe (5493.22, Mn (253.63, and Cu (1.825. It was also observed that Zn although present in soil samples, it was below detection limits in case of water samples. The As concentration in soil and water showed a positive correlation. Also the correlation analyses between soil arsenic and other heavy metals shows a positive co-relation with all of them.

  13. Limiting nitrogen and veterinary pharmaceutical input into groundwater: combining hydrogeophysics and soil science

    Science.gov (United States)

    Noell, Ursula; Stadler, Susanne

    2017-04-01

    The EU Interreg project TOPSOIL investigates opportunities to improve surface and groundwater quality as well as water management strategies under the consideration of climate adaptation challenges. Within the framework of the project, we investigate the transport behavior of percolation water in the unsaturated zone, the migration of nitrogen and veterinary pharmaceuticals in soils, and - together with different stakeholders (e.g. farmers, water supply companies) - develop common strategies to minimize the migration of these substances into the groundwater. In our study we focus on distinguishing preferential and diffuse flow using soil scientific and geophysical methods. During the first investigation campaign, we combined soil sampling with radiometry and electrical conductivity overview measurements on the typical sandy soil of the studied area south of Oldenburg, Germany. We used the CMD explorer for the electromagnetic mapping (horizontal and vertical dipoles, intercoil spacing of 1.48/2.82/4.49 m, investigations depths of appr. 0 - 6 m) and the radiometry detector comprised five sodium-iodide crystals each with a volume of 4 litres. The spectral data are evaluated for potassium (1.37 - 1.57 MeV), uranium (Bi-214) (1.66 - 1.86MeV) and thorium (T-208) (2.41 - 2.81MeV) and total counts (0.41-2.81MeV). A total of 292 soil samples were taken from 46 ram coring profiles (depth range: 0 to 3 m) and analyzed for soil chemical parameters and water content. The first evaluation showed a good correlation between conductivity and radiometry measurements. While the uranium and thorium values are generally low, the potassium values possibly reflect higher clay contents as do the higher conductivity values. The geophysical overview measurements were used to select the locations for soil sampling and we specifically targeted presumably clay-rich as well as clay-poor areas for sampling.

  14. Evaluation of short-term tracer fluctuations in groundwater and soil air in a two year study

    Science.gov (United States)

    Jenner, Florian; Mayer, Simon; Aeschbach, Werner; Weissbach, Therese

    2016-04-01

    The application of gas tracers like noble gases (NGs), SF6 or CFCs in groundwater studies such as paleo temperature determination requires a detailed understanding of the dynamics of reactive and inert gases in the soil air with which the infiltrating water equilibrates. Due to microbial gas consumption and production, NG partial pressures in soil air can deviate from atmospheric air, an effect that could bias noble gas temperatures estimates if not taken into account. So far, such an impact on NG contents in groundwater has not been directly demonstrated. We provide the first long-term study of the above mentioned gas tracers and physical parameters in both the saturated and unsaturated soil zone, sampled continuously for more than two years near Mannheim (Germany). NG partial pressures in soil air correlate with soil moisture and the sum value of O2+CO2, with a maximal significant enhancement of 3-6% with respect to atmospheric air during summer time. Observed seasonal fluctuations result in a mass dependent fractionation of NGs in soil air. Concentrations of SF6 and CFCs in soil air are determined by corresponding fluctuations in local atmospheric air, caused by industrial emissions. Arising concentration peaks are damped with increasing soil depth. Shallow groundwater shows short-term NG fluctuations which are smoothed within a few meters below the water table. A correlation between NG contents of soil air and of groundwater is observable during strong recharge events. However, there is no evidence for a permanent influence of seasonal variations of soil air composition on shallow groundwater. Fluctuating NG contents in shallow groundwater are rather determined by variations of soil temperature and water table level. Our data gives evidence for a further temperature driven equilibration of groundwater with entrapped air bubbles within the topmost saturated zone, which permanently occurs even some years after recharge. Local subsurface temperature fluctuations

  15. Tools based on multivariate statistical analysis for classification of soil and groundwater in Apulian agricultural sites.

    Science.gov (United States)

    Ielpo, Pierina; Leardi, Riccardo; Pappagallo, Giuseppe; Uricchio, Vito Felice

    2017-06-01

    In this paper, the results obtained from multivariate statistical techniques such as PCA (Principal component analysis) and LDA (Linear discriminant analysis) applied to a wide soil data set are presented. The results have been compared with those obtained on a groundwater data set, whose samples were collected together with soil ones, within the project "Improvement of the Regional Agro-meteorological Monitoring Network (2004-2007)". LDA, applied to soil data, has allowed to distinguish the geographical origin of the sample from either one of the two macroaeras: Bari and Foggia provinces vs Brindisi, Lecce e Taranto provinces, with a percentage of correct prediction in cross validation of 87%. In the case of the groundwater data set, the best classification was obtained when the samples were grouped into three macroareas: Foggia province, Bari province and Brindisi, Lecce and Taranto provinces, by reaching a percentage of correct predictions in cross validation of 84%. The obtained information can be very useful in supporting soil and water resource management, such as the reduction of water consumption and the reduction of energy and chemical (nutrients and pesticides) inputs in agriculture.

  16. 持久性有机污染场地土壤淋洗法修复研究进展%REVIEW OF REMEDIATION OF POPs CONTAMINATED SITES WITH SOIL WASHING METHOD

    Institute of Scientific and Technical Information of China (English)

    叶茂; 杨兴伦; 魏海江; 卞永荣; 王芳; 谷成刚; 蒋新

    2012-01-01

    持久性有机污染场地土壤淋洗法是污染场地土壤物化修复方法中一种常用的技术.淋洗法是指运用特定淋洗剂对污染土壤进行深度洗涤,通过分离净化淋洗剂,实现回用集成,达到去除土壤中污染物的目的,并最终安全化处置污染物和修复土壤的过程.本文根据污染场地土壤处理位置、淋洗剂种类和淋洗剂施用方式的差异,将持久性有机污染场地土壤淋洗法划分为不同的种类;总结了为达到高效去除土壤中污染物质,可运用多级淋洗方式、超声方式、电动力方式和化学氧化等方式实现强化修复效率;阐述了污染场地土壤质地、污染物性质、淋洗剂性质、淋洗条件优化以及淋洗剂回用效率等因素对淋洗修复整体效用的显著影响;同时指出了目前持久性有机污染场地土壤淋洗法存在的问题和今后国内外研究和应用的方向.综合考虑土壤淋洗修复技术适用范围和成本因素,认为淋洗法是一种较符合我国持久性有机污染场地土壤实情的修复技术,具有较强的针对性和较广泛的运用前景.%Soil washing is one of the most used physical and chemical methods in remediation of POPs contaminated sites. This method refers to the process of washing the contaminated soil in depth with an object-specific kind of washing solution; pooling the solution for separation of the pollutants; recycling the purified solution for reuse; and safely disposing the pollutants. Owing to differences in position of soil washing at the contaminated site, type of the washing solution and way of the washing, soil washing varies in type, like multi-step washing, washing aided with ultrasound waves, electricity-powered washing, chemical washing, etc. , which can be selected for use site-specifically to enhance effectiveness of the washing. Efficiency of the remediation is obviously affected by a number of factors, such as soil texture, properties of

  17. Greenhouse gas emission and groundwater pollution potential of soils amended with raw swine manure, dry and wet pyrolyzed swine biochars

    Science.gov (United States)

    The objective of this research is to study the greenhouse gas emission and groundwater pollution potentials of the soils amended with raw swine solid and swine biochars made from different thermochemical conditions. Triplicate sets of small pots were designed: 1) control soil with a 50/50 mixture of...

  18. Organizing groundwater regimes and response thresholds by soils: A framework for understanding runoff generation in a headwater catchment

    Science.gov (United States)

    John P. Gannon; Scott W. Bailey; Kevin J. McGuire

    2014-01-01

    A network of shallow groundwater wells in a headwater catchment at the Hubbard Brook Experimental Forest in New Hampshire, U.S. was used to investigate the hydrologic behavior of five distinct soil morphological units. The soil morphological units were hypothesized to be indicative of distinct water table regimes. Water table fluctuations in the wells were...

  19. Groundwater-soil-crop relationship with respect to arsenic contamination in farming villages of Bangladesh - A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Kurosawa, Kiyoshi [Institute of Tropical Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi -Ku, Fukuoka 812 8581 (Japan)], E-mail: kurosawa@agr.kyushu-u.ac.jp; Egashira, Kazuhiko [Faculty of Agriculture, Kyushu University, Fukuoka 812 8581 (Japan); Tani, Masakazu [Faculty of Design, Kyushu University, Fukuoka 815 8540 (Japan); Jahiruddin, M.; Moslehuddin, Abu Zofar Md. [Department of Soil Science, Bangladesh Agricultural University, Mymensingh 2202 (Bangladesh); Rahman, Zulfikar Md. [Department of Agricultural Extension Education, Bangladesh Agricultural University, Mymensingh 2202 (Bangladesh)

    2008-11-15

    To clarify the groundwater-soil-crop relationship with respect to arsenic (As) contamination, As concentration was measured in tubewell (TW) water, surface soil from farmyards and paddy fields, and fresh taro (Colocasia esculenta) leaves from farmyards in the farming villages of Bangladesh. The As concentration in TW water from farmyards was at least four times higher than the Bangladesh drinking water standard, and the concentration in fresh taro leaves was equal to or higher than those reported previously for leafy vegetables in Bangladesh. As concentration of surface soils in both farmyards and paddy fields was positively correlated with that of the TW water. Further, the concentration in surface soil was positively correlated with levels in fresh taro leaves in the farmyard. This study, therefore, clarified the groundwater-soil-crop relationship in farmyards and the relationship between groundwater-soil in paddy fields to assess the extent of As contamination in Bangladeshi villages. - By extracting arsenic contaminated groundwater from a well, surface soil surrounding the well and crops planted in the surface soil became contaminated with arsenic.

  20. PHYSICO-CHEMICAL ASSESSMENT OF AGRICULTURAL POLLUTION ON GROUNDWATER AND SOIL QUALITY IN AN AGRICULTURAL FARM (NORTH EASTERN MOROCCO

    Directory of Open Access Journals (Sweden)

    S. Fetouani

    2013-11-01

    Full Text Available To ensure sustainable food security, Morocco gives priority to agricultural and rural development by promoting investment in agricultural sector and use of intensification factors to improve incomes in rural areas. The Triffa irrigated perimeter is one of the oldest and the most productive in the country thanks to the Mohammed the V dam activity and the beginning of agricultural development intensification. Although this intensification has a positive effect on agricultural yields, it has negative impacts on soil and generatesgroundwater quality degradation. Indeed, recent studies performed in this area by us and Bendra (Fetouani et al., 2008; Bendra et al, 2012 have mentioned the existence of salinity problems, nitric groundwater pollution and soils salinization. This degradation is caused essentially by intensive use of agrochemicals, including nitrogen fertilizers and pesticides, and non-control of irrigation and cultivated plots drainage. However, a degradation of groundwater and soil quality is not without risk to Human health. Having a global vision about situation of groundwater and soil quality in the Triffa plain we have decided to deepen this theme to a local scale and to study in details the impact of intensive agriculture on groundwater and soil quality in a farm, located in the centre of the Triffa plain.To sum up the results of this study the state of soil quality in the farm is not alarming. However, the groundwater quality is mainly dramatic, because it is a receptacle of all the nutrients applied on the surface, especially nitrates.

  1. Heterogeneity of soil organic matter composition and its fate across ecosystem boundaries, or does it all come out in the wash?

    Science.gov (United States)

    Marin-Spiotta, E.; Berhe, A. A.; Barnes, R.

    2015-12-01

    A grand challenge in our understanding of the global carbon cycle is the vulnerability of large organic carbon pools at the land-water interface to changes in climate and to landscape disturbance. The expectation that terrestrial organic matter (OM) should be dominated by lignified (aromatic) plant-derived material or nitrogen-poor, complex soil OM with old radiocarbon ages has contributed to predictions of low bioavailability or chemical recalcitrance for terrigenous OM. Recent shifts in our understanding of the source of OM in soils and the mechanisms contributing to its persistence or loss have refocused attention on environmental parameters influencing the fate of OM and its role as a source of C to the atmosphere. On land, climate, soil mineralogy, topography, drainage, vegetation, disturbance (e.g., fire) and human land use influence the quantity and biochemical composition of organic matter accumulating in soils and available for lateral transfer to aquatic systems in dissolved or particulate form. Growing research indicates that local site conditions and disturbance history are important for predicting the response of soil OM to environmental change, often more so than OM chemical composition, contradicting traditional models that tie reactivity to structure. Soils are a large source of C entering waterways, yet how much landscape heterogeneity within the watershed matters for understanding the fate of C downstream is unknown: does all this heterogeneity come out in the wash? Here we follow up on recent discussions about environmental controls on the composition and age of OM in soil, what type and age of C is mobilized during landscape disturbance, and how its source on land can help predict its fate downstream. To further improve understanding of how landscape alterations affect transfers from land to water and fill some of the gaps in the global C cycle, we identify areas of research where collaborations between aquatic and terrestrial scientists would

  2. Multimedia model of atrazine in plant-soil-groundwater system with a fugacity approach.

    Science.gov (United States)

    Ye, C M; Lei, Z F; Wang, X J; Gong, A J; Zheng, H H

    2001-10-01

    The application of atrazine in China during the last ten years has led to some environmental problems. In this paper, the multimedia model of atrazine in soil-plant-groundwater system at Baiyangdian Lake area in Northern China was established using a fugacity approach, and verified with observed values. The model involved 7 environmental compartments which are air, groundwater, soil, corn roots, corn stem, corn leaf and kernel of corn. The results showed that the relative errors between calculated and observed values have a mean value of 24.7%, the highest value is 48% and the lowest value is 1.4%. All these values indicated that this multimedia model can be used to simulate the environmental fate of atrazine. Both the calculated and observed values of concentrations of atrazine in plant compartments are in the following order: in corn roots > in corn stem > in kernel of corn > in corn leaf, it exhibited a good regularity. The prediction results indicated that concentrations of atrazine in the groundwater and kernel of corn will override the limitation of 3 micrograms/L and 0.05 mg/kg respectively.

  3. Modelling water flow and seasonal soil moisture dynamics in analluvial groundwater-fed wetland

    Directory of Open Access Journals (Sweden)

    I. Joris

    2003-01-01

    Full Text Available Complex interactions occur in riparian wetlands between groundwater, surface water and climatic conditions. Knowledge of the hydrology of these systems is necessary to understand their functioning and their value and models are a useful and probably essential tool to capture their hydrological complexity. In this study, a 2D-model describing saturated-unsaturated water flow is applied to a transect through a groundwater-fed riparian wetland located along the middle reach of the river Dijle. The transect has high levees close to the river and a depression further into the floodplain. Scaling factors are introduced to describe the variability of soil hydraulic properties along the transect. Preliminary model calculations for one year show a good agreement between model calculations and measurements and demonstrate the capability of the model to capture the internal groundwater dynamics. Seasonal variations in soil moisture are reproduced well by the model thus translating external hydrological boundary conditions to root zone conditions. The model proves to be a promising tool for assessing effects of changes in hydrological boundary conditions on vegetation type distribution and to gain more insight in the highly variable internal flow processes of riparian wetlands. Keywords: riparian wetland,eco-hydrology, upward seepage, floodplain hydrology

  4. Pollution of soil and groundwater from infiltration of highly contaminated stormwater - a case study

    DEFF Research Database (Denmark)

    Mikkelsen, P.S.; Häfliger, M.; Ochs, M.

    1997-01-01

    A surface and a sub-surface infiltration system that received runoff water from trafficked roads for several decades was dug up and the contamination with heavy metals, PAH and AOX was investigated. Most measured solid phase concentrations exceeded background concentrations in nearby surface soils...... and subsurface sediments and some even exceeded guidelines fixed to preserve the fertility of soil. However, the contamination decreased rapidly with depth. None of the measured metal concentrations in simulated soil solutions exceeded defined drinking water quality standards. Surprisingly, the surface...... and the sub-surface infiltration system seemed to be equally good at retaining pollution. This indicates that the runoff sludge found in such infiltration systems plays an important role both as a source and a sorbent for stormwater contaminants. The study does not point at a considerable risk for groundwater...

  5. The use of ultrasound-assisted anaerobic compost tea washing to remove poly-chlorinated dibenzo-p-dioxins (PCDDs), dibenzo-furans (PCDFs) from highly contaminated field soils.

    Science.gov (United States)

    Hung, Weiteng; Huang, Wen-Yen; Lin, Chitsan; Vu, Chi Thanh; Yotapukdee, Siwalee; Kaewlaoyoong, Acharee; Chen, Jenq-Renn; Shen, Yun-Hwei

    2017-06-27

    The remediation of dioxin-contaminated soil of a specific coastal area previously employed for the manufacture of pentachlorophenol (PCP) in southern Taiwan's Tainan City has attracted much attention of researchers there. This work addresses the possibility of providing an effective and environmentally friendly option for removing PCDD/Fs from soil in that field. Soil screening/sieving was first conducted to assess particle distribution. Fine sand was observed to be the major component of the soil, accounting for more than 60% of the total mass. A combination of ultrasonification and mechanical double-blade agitation was used to facilitate the washing of the soil using the biosurfactant anaerobic compost tea. More than 85 and 95% of total removal efficiencies were achieved for moderately and highly contaminated soils after 6 and 10 washing cycles, respectively, under ambient temperature, a soil/liquid ratio 1:2.5, 700 rpm, and over a relatively short duration. These results were achieved through the collision and penetration effects of this combined treatment as well as PCDD/F partitioning between the particles and anaerobic compost tea. This study represents the first to report the use of anaerobic compost tea solvent to wash soil highly contaminated by dioxin. It was concluded that anaerobic compost tea, rich in non-toxic bio-surfactants (e.g., alcohols, humic acids), can be used to improve bioavailability and bioactivity of the soil making bio-attenuation and full remediation more efficient.

  6. Enhanced soil washing process for the remediation of PBDEs/Pb/Cd-contaminated electronic waste site with carboxymethyl chitosan in a sunflower oil-water solvent system and microbial augmentation.

    Science.gov (United States)

    Ye, Mao; Sun, Mingming; Wan, Jinzhong; Fang, Guodong; Li, Huixin; Hu, Feng; Jiang, Xin; Kengara, Fredrick Orori

    2015-02-01

    An innovative ex situ soil washing technology was developed to remediate polybrominated diphenyl ethers (PBDEs) and heavy metals in an electronic waste site. Elevated temperature (50 °C) in combination with ultrasonication (40 kHz, 20 min) at 5.0 mL L(-1) sunflower oil and 2.5 g L(-1) carboxymethyl chitosan were found to be effective in extracting mixed pollutants from soil. After two successive washing cycles, the removal efficiency rates for total PBDEs, BDE28, BDE47, BDE209, Pb, and Cd were approximately 94.1, 93.4, 94.3, 99.1, 89.3, and 92.7 %, respectively. Treating the second washed soil with PBDE-degrading bacteria (Rhodococcus sp. strain RHA1) inoculation and nutrient addition for 3 months led to maximum biodegradation rates of 37.3, 52.6, 23.9, and 1.3 % of the remaining total PBDEs, BDE28, BDE47, BDE209, respectively. After the combined treatment, the microbiological functions of washed soil was partially restored, as indicated by a significant increase in the counts, biomass C, N, and functioning diversity of soil microorganisms (p remediated soil was limited. Therefore, the proposed combined cleanup strategy is an environment-friendly technology that is important for risk assessment and management in mixed-contaminated sites.

  7. Characterization and fingerprinting of soil and groundwater contamination sources around a fuel distribution station in Galicia (NW Spain).

    Science.gov (United States)

    Balseiro-Romero, María; Macías, Felipe; Monterroso, Carmen

    2016-05-01

    Soil and groundwater contamination around a fuel distribution station in Tomiño (NW Spain) was evaluated. For this purpose, top and subsoil (up to 6.4 m) and groundwater were sampled around the station, approximately in a 60-m radius. Samples were analysed by HS-SPME-GC-MS to identify and quantify volatile fuel organic compounds (VFOC) (MTBE, ETBE and BTEX) and diesel range organics (DRO). Analysis and fingerprinting data suggested that the contamination of soil and groundwater was provoked by a fuel leak from underground storage tanks. This was reflected by hydrocarbon indices and principal component analysis, which discriminated a direct source of contamination of the subsoil samples around the station. The contaminants probably migrated from tank nearby soils to surrounding soils and leached to groundwater, following a SW direction. Irrigation with contaminated groundwater provoked a severe contamination of topsoils, which were enriched with the lightest components of gasoline and diesel. Fingerprinting also revealed the continuity of the leak, reflected by the presence of volatiles in some samples, which principally appeared in fresh leaks. MTBE was detected in a very high concentration in groundwater samples (up to 690 μg L(-1)), but it was not detected in fresh gasoline. This also evidenced an old source of contamination, probably starting in the mid-1990s, when the use of MTBE in gasoline was regulated.

  8. Surfactant enhanced washing of heavily oil-contaminated soil%表面活性剂清洗处理重度石油污染土壤

    Institute of Scientific and Technical Information of China (English)

    卢媛; 马小东; 孙红文; 张闻

    2009-01-01

    Four kinds of anionic-nonionic mixed surfaetant were used in surfactant enhanced washing of oilcontaminated soil samples from Shengli Oilfield,in Dongying City of Shandong Province.The effects of different systems with variOUS mass ratios of anionic and nonionic surfactants.total surfaetant concentrations,temperatures and assistant washing agents on oil removal efficiency were studied.The optimum conditions are:mixed surfactants of LAS and T×100 with a mass ratio of 8:2.total surfactant concentrations of 3 g/L,assistant washing agents concentration of 5 s/L.and a temperature of 75℃.After washing,the oil content of sample reduces from 20%to 4.6%.achieves an oil removal of 76.9%.The resuhs from wash water reusing experiments show that reusing from 30% to 100% of the wash water can remove more than 55% of oil contaminants in the first reusing process.In wash water's second time reusing.it can still achieve an oil removal of 18.8%.%为了优化表面活性剂清洗处理重度石油污染土壤的方法和具体洗脱条件参数,采集山东省东营市胜利油田污染土壤,研究了阴离子-非离子混合表面活性剂对该土壤中石油类污染物的去除效果.应用化学热洗原理,主要考查了表面活性剂配比、投加量、清洗温度及清洗助剂对去除效果的影响.实验得到的清洗处理最佳条件为:使用LAS与TX-100质量比为8:2的组合表面活性剂,总表面活性剂浓度为3 g/L,助剂硅酸钠浓度为5 g/L,75℃条件下搅拌1 h.清洗后土壤含油量从20%下降到4.6%,去除率达到76.9%.废水回用实验表明,清洗处理的废水对土壤中石油烃类物质仍有一定的去除效果.废水回用比从30%到100%时,对土壤中石油烃的去除率都可达到55%以上.对废水进行二次回用时仍能去除18.8%的污染物.

  9. Assessment of metal contamination in groundwater and soils in the Ahangaran mining district, west of Iran.

    Science.gov (United States)

    Mehrabi, Behzad; Mehrabani, Shiva; Rafiei, Behrouz; Yaghoubi, Behrouz

    2015-12-01

    In this study, 28 groundwater and 13 soil samples from Ahangaran mining district in Hamedan Province, west of Iran were collected to evaluate the level of contamination. Average concentrations of As, Cu, Pb, Zn, Mn, Sb, and Ni in groundwater samples were 1.39, 3.73, 2.18, 9.37, 2.35, 4.44, and 5.50 μg/L (wet season), and 11.64, 4.92, 4.32, 14.77, 5.43, 4.12, and 0.98 μg/L (dry season), respectively. Results of groundwater samples analysis showed that the average of analyzed metals in the wet and dry seasons were below the permissible limits, except As in the dry season which displays concentrations that exceed US EPA water quality criteria recommended for drinking water. Also, the heavy metal pollution index (HPI) values in each sampling station were less than the critical index limit and were suitable for drinking. Factor analysis revealed that variables influential to groundwater quality in one season may not be as important in another season. Average concentrations of Ag, As, Cd, Cu, Pb, Sb, and Zn in soil samples were 2.61, 31.44, 0.51, 55.90, 1284.9, 21.26, and 156.04 mg kg(-1), respectively. The results of the geoaccumulation index (I geo) showed the following decreasing order: Pb > Zn > Cu > As > Sb > Cd > Ag. Potential ecological risk index (RI) suggests that the contamination in the investigated area is moderate to very high risk and the ranking of the contaminants in decreasing order is Ag > Sb > Pb > Cd > As > Cu > Zn.

  10. 表面活性剂对土壤中多氯联苯的洗脱研究%Washing Polychlorinated Biphenyls from Contaminated Soils by Surfactants

    Institute of Scientific and Technical Information of China (English)

    陈涛; 王斯佳; 马慧; 杨晓瑛; 朱宝余

    2012-01-01

    Experiment was done in laboratory to wash polychlorinated biphenyls (PCBs) contaminated soil using 4 kinds of surfactants such as Triton X-100, Tween-80, sodium dodecyl sulfate (SDS) and sodium dodecylbenene sulfate(SDBS). Results showed that washing efficiency of SDS was the best in experimental conditions when single anionic surfactant was applied. The best solid-liquid ratio was 1 : 20, and two or three time elution was necessary to get better elution efficiency, but elution time didn't affect elution effect obviously. Anionic -nonionic mixed surfactants not only increased the solubilization of PCBs, but also reduced the sorption onto soils. When SDS-Tween-80 mixed surfactants were applied at 7 000 mg/L, in the best mass ratio conditions of 5 '. 5,97.89% PCBs was washed out from the laboratory contaminated soil after 3 times elution.%采用实验室配置的PCBs污染土壤,以曲拉通X-100、吐温-80、SDS、SDBS 4种表面活性剂进行洗脱试验研究.结果表明:对于单一表面活性剂,SDS对污染土壤中多氯联苯的洗脱效果最好;采用1∶20的固液比,进行2~3次洗脱,洗脱率可达50%以上;洗脱时间对洗脱效果影响不大;SDS-吐温-80混合表面活性剂对多氯联苯有协同增溶作用,且在土壤上的吸附损失较小,SDS和吐温-80的最佳质量比为5∶5,在此条件下,浓度为7 000 mg/L的混合表面活性剂对多氯联苯污染土壤进行3次洗脱,洗脱率可高达97.89%.

  11. Experimental and numerical investigations of soil water balance at the hinterland of the Badain Jaran Desert for groundwater recharge estimation

    Science.gov (United States)

    Hou, Lizhu; Wang, Xu-Sheng; Hu, Bill X.; Shang, Jie; Wan, Li

    2016-09-01

    Quantification of groundwater recharge from precipitation in the huge sand dunes is an issue in accounting for regional water balance in the Badain Jaran Desert (BJD) where about 100 lakes exist between dunes. In this study, field observations were conducted on a sand dune near a large saline lake in the BJD to investigate soil water movement through a thick vadose zone for groundwater estimation. The hydraulic properties of the soils at the site were determined using in situ experiments and laboratory measurements. A HYDRUS-1D model was built up for simulating the coupling processes of vertical water-vapor movement and heat transport in the desert soil. The model was well calibrated and validated using the site measurements of the soil water and temperature at various depths. Then, the model was applied to simulate the vertical flow across a 3-m-depth soil during a 53-year period under variable climate conditions. The simulated flow rate at the depth is an approximate estimation of groundwater recharge from the precipitation in the desert. It was found that the annual groundwater recharge would be 11-30 mm during 1983-2012, while the annual precipitation varied from 68 to 172 mm in the same period. The recharge rates are significantly higher than those estimated from the previous studies using chemical information. The modeling results highlight the role of the local precipitation as an essential source of groundwater in the BJD.

  12. Radioactivity in rocks and soil and interaction with groundwater in an arid region

    Science.gov (United States)

    Alshamsi, Dalal; Murad, Ahmed; Aldahan, Ala; Hou, Xiaolin; El Saiy, Ayman

    2014-05-01

    Interaction of groundwater with soil and rocks changes the chemical composition of the water both spatially and temporally. In arid regions, surficial recharge of groundwater is generally limited to sporadic rainfall events which may cause rapid interaction between the recharge water and the aquifers materials. Among the elements that commonly increase in concentration as groundwater interact with the aquifer materials are the radioactive elements such as uranium and thorium and their decay chain products. Here, we present data on 235U, 238U, 232Th as well as 137Cs in some sediments and rock aquifers located in the United Arab Emirates (UAE) in southeastern Arabian Peninsula. The Quaternary sediments are composed of silt, sand and gravel with varying proportions of quartz, carbonates, feldspars, evaporites, while the carbonates are mainly limestones, dolomitic limestones, dolomite and calcareous mudstones. These carbonate rocks cover ages extending from 10-230 Myr. After complete digestion using fluoric and nitric acids and chemical separation, the isotopes were measured using ICP-MS. The 235U, 238U and 232Th concentrations ranges are 2.66-32.5 ng/g, 354.7-4453 ng/g and 13.2-1367 ng/g respectively in the carbonate rocks. In the sediments the concentrations are 4.6-17.5 ng/g for 235U, 631.7-2406 ng/g for 238U and 25.6-799.6 ng/g for 232Th. Although it is difficult to quantify the amounts of uranium isotopes that enter the hydrological system from the aquifers, it seems that in the presence of carboxyl ions, uranium forms highly soluble complexes which can be transported to large distances in groundwater. The variations in 232Th concentrations are probably controlled by the availability of sulfate salt rocks (like gypsum) interacting with thorium and forming soluble thorium compounds which can also explain the highly variable concentrations in groundwater.

  13. Groundwater influence on soil moisture memory, ET fluxes and the seasonal cycle of streamflow in the Iberian Peninsula

    Science.gov (United States)

    Martinez-de la Torre, Alberto; Miguez-Macho, Gonzalo

    2014-05-01

    In this work we investigate the memory induced in soil moisture fields by groundwater long timescales of variation in the Iberian Peninsula with the LEAFHYDRO soil-vegetation-hydrology model, which includes a fully coupled water table to soil moisture and river flow via 2-way fluxes. We select a 10-year period (1989-2000) with transitions from wet to dry to again wet long lasting conditions and we carry out simulations at 2.5 km spatial resolution forced by ERA-Interim and a high-resolution precipitation analysis over Spain and Portugal. The model produces a realistic water table that we validate with hundreds of time series (ranging from 4 to 10 years) of observations over the Iberian Peninsula. Modeled river flow is also compared to observations. Over shallow water table regions, results highlight the groundwater buffering effect on soil moisture fields over dry spells and long-term droughts, as well as the slow recovery of pre-drought soil wetness once climatic conditions turn wetter. Groundwater sustains river flow during the dry summers and in turn, particularly in the south of Spain where the summer drought is more pronounced, river seepage feeds groundwater in wide valleys, keeping the water table shallow. The longer lasting wet conditions in the soil when groundwater is considered increases ET, especially in the summer, when it is mostly water-limited. Our results suggest that groundwater interaction with soil moisture should be considered for climate seasonal forecasting and climate studies in general over water-limited regions where shallow water tables are significantly present.

  14. Soil and groundwater contamination with heavy metals at two scrap iron and metal recycling facilities

    DEFF Research Database (Denmark)

    Jensen, Dorthe Lærke; Holm, P. E.; Christensen, Thomas Højlund

    2000-01-01

    Field studies were performed at two actual scrap iron and metal recycling facilities in order to evaluate the extent of heavy metal migration into subsoil and groundwater caused by more than 25 years of handling scrap directly on the ground without any measures to prevent leaching. Surface soil...... samples, called `scrap dirt', representing the different activities on the two recycling facilities, all showed very high concentrations of lead (Pb), copper (Cu) and zinc (Zn), high concentrations of cadmium (Cd) , chromium (Cr) and nickel (Ni) and somewhat elevated concentrations of many other metals...

  15. In Situ Chemical Oxidation of Contaminated Soil and Groundwater Using Persulfate

    DEFF Research Database (Denmark)

    Tsitonaki, Aikaterini; Petri, B.; Crimi, M.

    2010-01-01

    Persulfate is the newest oxidant that is being used for in situ chemical oxidation (ISCO) in the remediation of soil and groundwater. In this review, the fundamental reactions and governing factors of persulfate relevant to ISCO are discussed. The latest experiences for ISCO with persulfate...... are presented, with a focus on the different activation methods, the amenable contaminants, and the reactions of persulfate with porous media, based primarily on a critical review of the peer-reviewed scientific literature and to a lesser extent on non-reviewed professional journals and conference proceedings...

  16. [Groundwater].

    Science.gov (United States)

    González De Posada, Francisco

    2012-01-01

    From the perspective of Hydrogeology, the concept and an introductory general typology of groundwater are established. From the perspective of Geotechnical Engineering works, the physical and mathematical equations of the hydraulics of permeable materials, which are implemented, by electric analogical simulation, to two unique cases of global importance, are considered: the bailing during the construction of the dry dock of the "new shipyard of the Bahia de Cádiz" and the waterproofing of the "Hatillo dam" in the Dominican Republic. From a physical fundamental perspective, the theories which are the subset of "analogical physical theories of Fourier type transport" are related, among which the one constituted by the laws of Adolf Fick in physiology occupies a historic role of some relevance. And finally, as a philosophical abstraction of so much useful mathematical process, the one which is called "the Galilean principle of the mathematical design of the Nature" is dealt with.

  17. Characterization of contaminated soil and groundwater surrounding an illegal landfill (S. Giuliano, Venice, Italy) by principal component analysis and kriging

    Energy Technology Data Exchange (ETDEWEB)

    Critto, Andrea; Carlon, Claudio; Marcomini, Antonio

    2003-04-01

    Information on soil and groundwater contamination was used to develop a site conceptual model and to identify exposure scenarios. - The characterization of a hydrologically complex contaminated site bordering the lagoon of Venice (Italy) was undertaken by investigating soils and groundwaters affected by the chemical contaminants originated by the wastes dumped into an illegal landfill. Statistical tools such as principal components analysis and geostatistical techniques were applied to obtain the spatial distribution of chemical contaminants. Dissolved organic carbon (DOC), SO{sub 4}{sup 2-} and Cl{sup -} were used to trace the migration of the contaminants from the top soil to the underlying groundwaters. The chemical and hydrogeological available information was assembled to obtain the schematic of the conceptual model of the contaminated site capable to support the formulation of major exposure scenarios, which are also provided.

  18. Rare earth elements and titanium in plants, soils and groundwaters in the alkaline-ultramafic complex of Salitre, MG Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Ceccantini, G. [Instituto de Biociencias, Sao Paulo, (Brazil). Dept. de Botanica; Figueiredo, A.M.G. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Div. de Radioquimica; Sondag, F.; Soubies, F. [ORSTOM, 93 - Bondy (France); Soubies, F. [Universite Paul Sabatier, 31 - Toulouse (France)

    1997-12-31

    The contents of rare earth elements (REE) and titanium in various plant species, in groundwaters and in soils from the alkaline-ultramafic complex of Salitre, have been determined. Due to the the particular mineralogy of the bedrock, REE and Ti exhibit high concentrations in the soils. Despite this, plants generally present REE concentrations within the ranges usually found in plants, and the transfer factor from soil to plant is at least ten times below the range reported in the literature, confirming that the concentrations of REE in the plants are widely independent of the soil content. All species present normalized patterns similar to those of the soils, characterized by an enrichment in light REE. Several plants show Ti concentrations about three times higher than the reference values. It is suggested that in the studied ecosystem, the plant metabolism affect the REE distribution in the groundwaters, leading to an enrichment of the superficial waters in heavy REE

  19. Batch washing of saturated hydrocarbons and polycyclic aromatic hydrocarbons from crude oil contaminated soils using bio-surfactant

    Institute of Scientific and Technical Information of China (English)

    张文

    2015-01-01

    Desorption of total saturated fractions (i.e. SAT, defined for this study as the summation of the concentrations of the saturated hydrocarbon from n-C10 to n-C26) and polycyclic aromatic fractions (i.e. PAH, defined as the summation of the concentrations of all polycyclic aromatic fractions including the 16 EPA priority PAH) in two types of soils subjected to the changes of pH and salinity and different bio-surfactant concentrations were investigated. In general, compared with the experiments without bio-surfactant addition, adding rhamnolipid to crude oil−water systems at concentrations above its critical micelle concentration (CMC) values benefits SAT and PAH desorption. The results indicate that the change of pH could have distinct effects on rhamnolipid performance concerning its own micelle structure and soil properties. For loam soil, the adsorption of non-aqueous phase liquid (NAPL) and rhamnolipid would be the principle limiting factors during the NAPL removal procedure. For sand soil, less amount of rhamnolipid is adsorbed onto soil. Thus, with the increase of salinity, the solubilization and desorption of rhamnolipid solution are more significant. In summary, the pH and salt sensitivity of the bio-surfactant will vary according to the specific structure of the surfactant characteristics and soil properties.

  20. Promising approaches to the purification of soils and groundwater from hydrocarbons (A Review)

    Science.gov (United States)

    Vodyanitskii, Yu. N.; Trofimov, S. Ya.; Shoba, S. A.

    2016-06-01

    Soils and waters are affected by oil spills in the course of oil production and hydrocarbon leakages because of the corrosion of underground reservoirs, as well as the filtration of hydrocarbons from the tailing ponds formed during the extraction of oil from oil sands. The conventional technology for the withdrawal of contaminated water and its purification on the surface is low-efficient and expensive. New approaches are proposed for the in situ purification of soils and groundwater. To accelerate the oxidation, active substances atypical for the supergenesis zone are used: peroxides of metals and hydrogen. The efficiency of hydrogen peroxide significantly increases when the oxidation is catalyzed by Fe2+ or Fe3+ (Fenton reaction). The effects of Fe(III), sulfates, and carbon dioxide as electron acceptors are studied under anaerobic conditions (with oxygen deficit).

  1. Impact of Climate Change on Soil and Groundwater Chemistry Subject to Process Waste Land Application

    Science.gov (United States)

    McNab, W. W.

    2013-12-01

    Nonhazardous aqueous process waste streams from food and beverage industry operations are often discharged via managed land application in a manner designed to minimize impacts to underlying groundwater. Process waste streams are typically characterized by elevated concentrations of solutes such as ammonium, organic nitrogen, potassium, sodium, and organic acids. Land application involves the mixing of process waste streams with irrigation water which is subsequently applied to crops. The combination of evapotranspiration and crop salt uptake reduces the downward mass fluxes of percolation water and salts. By carefully managing application schedules in the context of annual climatological cycles, growing seasons, and process requirements, potential adverse environmental impacts to groundwater can be mitigated. However, climate change poses challenges to future process waste land application efforts because the key factors that determine loading rates - temperature, evapotranspiration, seasonal changes in the quality and quantity of applied water, and various crop factors - are all likely to deviate from current averages. To assess the potential impact of future climate change on the practice of land application, coupled process modeling entailing transient unsaturated fluid flow, evapotranspiration, crop salt uptake, and multispecies reactive chemical transport was used to predict changes in salt loading if current practices are maintained in a warmer, drier setting. As a first step, a coupled process model (Hydrus-1D, combined with PHREEQC) was calibrated to existing data sets which summarize land application loading rates, soil water chemistry, and crop salt uptake for land disposal of process wastes from a food industry facility in the northern San Joaquin Valley of California. Model results quantify, for example, the impacts of evapotranspiration on both fluid flow and soil water chemistry at shallow depths, with secondary effects including carbonate mineral

  2. Multimedia model of atrazine in plant-soil-groundwater system with a fugacity approach

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The application of atrazine in China during the last ten years has led to some environmental problems. In this paper, the multimedia model of atrazine in soil-plant-groundwater system atBaiyangdian Lake area in Northern China was established using a fugacity approach, and verified with observed values. The model involved 7 environmental compartments which are air, groundwater, soil, corn roots, corn stem, corn leaf and kernel of corn. Theresults showed that the relative errors between calculated and observed values have a mean value of 24.7%, the highest value is 48% and the lowest value is 1.4%. All these values indicated thatthis multimedia model can be used to simulate the environmental fate of atrazine. Both the calculated and observed values of conce ntrations of atrazine in plant compartments are in the ollowing order: in corn roots > in corn stem > in kernel of corn > in corn leaf, it exhibited a good regularity. The prediction results indicated that concentrations of atrazine in the roundwater and kernel of corn will override the limitation of 3L and 0.05 mg/kg respectively.

  3. Untangling the effects of shallow groundwater and soil texture as drivers of subfield-scale yield variability

    Science.gov (United States)

    Zipper, Samuel C.; Soylu, Mehmet Evren; Booth, Eric G.; Loheide, Steven P.

    2015-08-01

    Water table depth (WTD), soil texture, and growing season weather conditions all play critical roles in determining agricultural yield; however, the interactions among these three variables have never been explored in a systematic way. Using a combination of field observations and biophysical modeling, we answer two questions: (1) under what conditions can a shallow water table provide a groundwater yield subsidy and/or penalty to corn production?; and (2) how do soil texture and growing season weather conditions influence the relationship between WTD and corn yield?. Subfield-scale yield patterns during a dry (2012) and wet (2013) growing season are used to identify sensitivity to weather. Areas of the field that are negatively impacted by wet growing seasons have the shallowest observed WTD (perform consistently poorly are characterized by deep WTD (>3 m) and coarse soil textures. Modeling results find that beneficial impacts of shallow groundwater are more common than negative impacts under the conditions studied, and that the optimum WTD is shallower in coarser soils. While groundwater yield subsidies have a higher frequency and magnitude in coarse-grained soils, the optimum WTD responds to growing season weather at a relatively constant rate across soil types. We conclude that soil texture defines a baseline upon which WTD and weather interact to determine overall yield. Our work has implications for water resource management, climate/land use change impacts on agricultural production, and precision agriculture.

  4. Polar metabolites of polycyclic aromatic compounds from fungi are potential soil and groundwater contaminants.

    Science.gov (United States)

    Boll, Esther S; Johnsen, Anders R; Christensen, Jan H

    2015-01-01

    This study investigated the sorption to soil of water-soluble metabolites from polycyclic aromatic compounds (PACs). The soil fungus Cunninghamella elegans was used to produce PAC metabolites from two un-substituted PACs (phenanthrene, pyrene), three alkyl-substituted PACs (2-methylnaphthalene, 1-methylphenanthrene, 1-methylpyrene), and one sulfur-containing heterocyclic PAC (dibenzothiophene). Fifty-eight metabolites were tentatively identified; metabolites from the un-substituted PACs were hydroxylated and sulfate conjugated, whereas metabolites from alkyl-substituted PACs were sulfate conjugated and either hydroxylated or oxidized to carboxylic acids at the methyl group. The metabolism of the sulfur-containing heterocyclic PAC resulted in sulfate conjugates. The sorption of the PAC metabolites to three soils was determined using a batch equilibrium method, and partition coefficients (Kd's) were calculated for fourteen representative metabolites. Sulfate conjugated metabolites displayed Kd's below 70 whereas the metabolites with both a sulfate and a carboxylic acid group had Kd's below 2.8. The low Kd's of water-soluble PAC metabolites indicate high mobility in soil and a potential for leaching to surface- and groundwaters.

  5. Glyphosate and AMPA in U.S. streams, groundwater, precipitation and soils

    Science.gov (United States)

    Battaglin, William A.; Meyer, Michael T.; Kuivila, Kathryn; Dietze, Julie E.

    2014-01-01

    Herbicides containing glyphosate are used in more than 130 countries on more than 100 crops. In the United States (U.S.), agricultural use of glyphosate [N-(phosphonomethyl)glycine] has increased from less than 10,000 metric tons per year (active ingredient) in 1993 to more than 70,000 metric tons per year in 2006. In 2006, glyphosate accounted for about 20 percent of all herbicide use (by weight of active ingredient). Glyphosate formulations such as Roundup® are used in homes and in agriculture. Part of the reason for the popularity of glyphosate is the perception that it is an “environmentally benign” herbicide that has low toxicity and little mobility or persistence in the environment. The U.S. Geological Survey developed an analytical method using liquid chromatography/tandem mass spectrometry that can detect small amounts of glyphosate and its primary degradation product aminomethylphosphonic acid (AMPA) in water and sediment. Results from more than 2,000 samples collected from locations distributed across the U.S. indicate that glyphosate is more mobile and occurs more widely in the environment than was previously thought. Glyphosate and AMPA were detected (reporting limits between 0.1 and 0.02 micrograms per liter) in samples collected from surface water, groundwater, rainfall, soil water, and soil, at concentrations from less than 0.1 to more than 100 micrograms per liter. Glyphosate was detected more frequently in rain (86%), ditches and drains (71%), and soil (63%); and less frequently in groundwater (3%) and large rivers (18%). AMPA was detected more frequently in rain (86%), soil (82%), and large rivers (78%); and less frequently in groundwater (8%) and wetlands or vernal pools (37%). Most observed concentrations of glyphosate were well below levels of concern for humans or wildlife, and none exceeded the U.S. Environmental Protection Agency’s Maximum Contaminant Level of 700 micrograms per liter. However, the ecosystem effects of chronic low

  6. Record of Decision for Tank Farm Soil and INTEC Groundwater, Operable Unit 3-14

    Energy Technology Data Exchange (ETDEWEB)

    L. S. Cahn

    2007-05-16

    This decision document presents the selected remedy for Operable Unit (OU) 3-14 tank farm soil and groundwater at the Idaho Nuclear Technology and Engineering Center (INTEC), which is located on the Idaho National Laboratory (INL) Site. The tank farm was initially evaluated in the OU 3-13 Record of Decision (ROD), and it was determined that additional information was needed to make a final decision. Additional information has been obtained on the nature and extent of contamination in the tank farm and on the impact to groundwater. The selected remedy was chosen in accordance with the Comprehensive Environmental Response, Liability and Compensation Act of 1980 (CERCLA) (42 USC 9601 et seq.), as amended by the Superfund Amendments and Reauthorization Act of 1986 (Public Law 99-499) and the National Oil and Hazardous Substances Pollution Contingency Plan (40 CFR 300). The selected remedy is intended to be the final action for tank farm soil and groundwater at INTEC. The response action selected in this ROD is necessary to protect the public health, welfare, or the environment from actual or threatened releases of hazardous substances into the environment. Such a release or threat of release may present an imminent and substantial endangerment to public health, welfare, or the environment. The remedial actions selected in this ROD are designed to reduce the potential threats to human health and the environment to acceptable levels. In addition, DOE-ID, EPA, and DEQ (the Agencies) have determined that no action is necessary under CERCLA to protect public health, welfare, or the environment at 16 sites located outside the tank farm boundary. The purposes of the selected remedy are to (1) contain contaminated soil as the radionuclides decay in place, (2) isolate current and future workers and biological receptors from contact with contaminated soil, and (3) restore the portion of Snake River Plain Aquifer contaminated by INTEC releases to Idaho Ground Water Quality

  7. Streamflow forecasting and data assimilation: bias in precipitation, soil moisture states, and groundwater fluxes.

    Science.gov (United States)

    McCreight, J. L.; Gochis, D. J.; Hoar, T.; Dugger, A. L.; Yu, W.

    2014-12-01

    Uncertainty in precipitation forcing, soil moisture states, and model groundwater fluxes are first-order sources of error in streamflow forecasting. While near-surface estimates of soil moisture are now available from satellite, very few soil moisture observations below 5 cm depth or groundwater discharge estimates are available for operational forecasting. Radar precipitation estimates are subject to large biases, particularly during extreme events (e.g. Steiner et al., 2010) and their correction is not typically available in real-time. Streamflow data, however, are readily available in near-real-time and can be assimilated operationally to help constrain uncertainty in these uncertain states and improve streamflow forecasts. We examine the ability of streamflow observations to diagnose bias in the three most uncertain variables: precipitation forcing, soil moisture states, and groundwater fluxes. We investigate strategies for their subsequent bias correction. These include spinup and calibration strategies with and without the use of data assimilation and the determination of the proper spinup timescales. Global and spatially distributed multipliers on the uncertain states included in the assimilation state vector (e.g. Seo et al., 2003) will also be evaluated. We examine real cases and observing system simulation experiments for both normal and extreme rainfall events. One of our test cases considers the Colorado Front Range flood of September 2013 where the range of disagreement amongst five precipitation estimates spanned a factor of five with only one exhibiting appreciable positive bias (Gochis et al, submitted). Our experiments are conducted using the WRF-Hydro model with the NoahMP land surface component and the data assimilation research testbed (DART). A variety of ensemble data assimilation approaches (filters) are considered. ReferencesGochis, DJ, et al. "The Great Colorado Flood of September 2013" BAMS (Submitted 4-7-14). Seo, DJ, V Koren, and N

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

    Science.gov (United States)

    Lee, R.W.

    1991-01-01

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

  9. Study on Washing Aeolian Sandy Soil Contaminated by Crude Oil Using Orthogonal Experiment%正交试验法洗涤原油污染风砂土的初步研究

    Institute of Scientific and Technical Information of China (English)

    谢绿武; 郭亮; 石海良; 蒋小川; 赵红艳

    2011-01-01

    Self-made sodium humate, sodium hydroxide and commercial sodium humate were taken as the detergents to wash aeolian sandy soil polluted by crude oil. The orthogonal experiment was designed to obtain the optimal tern- perature, washing times and detergent types. The results showed that the most significant factor was washing times, the second one was detergent type, and the effect of wash temperature was the smallest. The best technics was using commercial sodium humate as detergent to wash polluted soil for 3 times under the condition of 60℃.%利用正交试验设计,选用市售腐植酸钠、自制腐植酸钠和碱水作为洗涤剂,在不同温度和洗涤次数的条件下对落地原油中度污染的土壤进行洗涤,分析洗涤剂种类、洗涤温度和洗涤次数3个因素对洗涤效果的影响。结果表明:洗涤次数对洗涤效果影响最为显著,洗涤剂种类次之,洗涤温度影响最小。试验最优方案为选用市售腐植酸钠,在60℃下洗涤3次(即A3B1C3)。

  10. 洗衣机净洗能力检测用血渍污染布的制备及性能评价%Preparation of blood soiled strips for the test of washing machine and evaluation of its washing performance

    Institute of Scientific and Technical Information of China (English)

    蒋黎; 王赢; 朱小雷; 王强; 范雪荣

    2014-01-01

    As one of the standard stain test strips in the international standard IEC 60456 , blood soiled strip was used to test the performance of washing protein pigment on clothes of washing machines .Blood soiled strips were prepared, and the effects of rolling over rate , drying temperature and aging time on the colour of the strips were discussed .The self-made blood soiled strips were compared with EMPA blood soiled strips by colour , evenness and washing performance .The results show that rolling over rate , drying temperature and aging time have great influence on strips’ colour, and the self-made blood soiled strips have similar colour , evenness and washing performance with those of EMPA .%血渍污染布(血污布)作为国际标准IEC 60456中检测洗衣机洗涤性能的标准污染布之一,目前国内研究较少。制备血污布,探讨轧余率、烘干温度与老化时间对血污布色度的影响,对比分析自制血污布与EMPA血污布色度、均匀性及净洗性能。结果表明:轧余率、烘干温度以及老化时间对血污布的颜色影响较大,自制血污布与EMPA血污布色度相近,均匀性良好,净洗性能相当。

  11. Using soil and Quaternary geological information to assess the intrinsic groundwater vulnerability of shallow aquifers: an example from Lithuania

    Science.gov (United States)

    Holman, I.; Palmer, R.; Leonavičiūtė, N.

    2000-12-01

    Lithuania, in the Baltic region of northern Europe, is heavily dependent on groundwater resources for its public water supply, with a large proportion, especially in rural areas, derived from shallow Quaternary aquifers. A national groundwater-vulnerability methodology, based upon the UK approach, has been developed on behalf of the Lithuanian Ministry of Environmental Protection as a possible basis for the future protection of shallow groundwater resources for the rural inhabitants. Some modifications to the UK methodology were required to enable archive data to be used. The four aquifer classes depicted on the final groundwater vulnerability map are based upon the assessed relative permeabilities of the uppermost Quaternary deposits. The derivation of the classification of soil-leaching potential required a reassessment of Soviet-based soil wetness and particle-size classes and a calculation of subsoil-saturated hydraulic conductivity. A preliminary validation of the final maps against available shallow groundwater samples suggests that the methodology satisfactorily predicts the intrinsic groundwater vulnerability. The final methodology, based upon its low-cost approach using archive data, is relevant to the current needs of Lithuania and can be applied in other regions of similar geology and climate.

  12. [Effect of soil texture in unsaturated zone on soil nitrate accumulation and groundwater nitrate contamination in a marginal oasis in the middle of Heihe River basin].

    Science.gov (United States)

    Su, Yong-Zhong; Yang, Xiao; Yang, Rong

    2014-10-01

    In irrigated agricultural ecosystems, the accumulation, distribution and transfer of nitrate nitrogen (NO(3-)-N) in soil profile and groundwater nitrate pollution were influenced by irrigation and fertilization, and were closely related to soil textural characteristics. In this study, a monitoring section with 10 groundwater observation wells along Heihe River flood land-old oasis croplands-newly cultivated sandy croplands-fixed sandy land outside oasis was established in Pingchuan desert-oasis in Linze county in the middle of Heihe river basin, and groundwater NO(3-)-N concentration was continuously monitored. Soil texture and NO(3-)-N concentration in the unsaturated zone at different landscape locations were determined. The NO(3-)-N transfer change in soil profile, nitrate leaching of soils with different texture and fertility levels in the 0-100 cm layer were analyzed. The results indicated that the vertical distribution of soil texture was sandy loam in the 0-130 cm depth, loam in the 130-190 cm and clay loam in the 190-300 cm for the old oasis croplands. For newly cultivated sandy croplands, sand content was more than 80% in each soil layer of the 0-300 cm profile, although a thin clay layer occurred in the 140-160 cm depth. The clay layer occurred 160 cm below the sand-fixing zone outside oasis. There were significant correlations between soil NO(3-)-N concentration and silt + clay content, and the order of significant degree was the natural soils of sandy lands > the newly cultivated sandy croplands > the old oasis croplands. The loss of N leaching was closely correlated to the silt + caly content in the 0-100 cm soil depth. The groundwater NO(3-)-N concentration varied from 1.01 to 5.17 mg · L(-1), with a mean value of 2.65 mg · L(-1) and from 6.6 to 29.5 mg · L(-1), with an average of 20.8 mg · L(-1) in the area of old oasis croplands and the newly cultivated croplands, respectively. The averaged groundwater NO(3-)-N concentration in the area of newly

  13. Method for the Preparation of Hazard Map in Urban Area Using Soil Depth and Groundwater Level

    Science.gov (United States)

    Kim, Sung-Wook; Choi, Eun-Kyeong; Cho, Jin Woo; Lee, Ju-Hyoung

    2017-04-01

    The hazard maps for predicting collapse on natural slopes consists of a combination of topographic, hydrological, and geological factors. Topographic factors are extracted from DEM, including aspect, slope, curvature, and topographic index. Hydrological factors, such as distance to drainage, drainage density, stream-power index, and wetness index are most important factors for slope instability. However, most of the urban areas are located on the plains and it is difficult to apply the hazard map using the topography and hydrological factors. In order to evaluate the risk of collapse of flat and low slope areas, soil depth and groundwater level data were collected and used as a factor for interpretation. In addition, the reliability of the hazard map was compared with the disaster history of the study area (Gangnam-gu and Yeouido district). In the disaster map of the disaster prevention agency, the urban area was mostly classified as the stable area and did not reflect the collapse history. Soil depth, drainage conditions and groundwater level obtained from boreholes were added as input data of hazard map, and disaster vulnerability increased at the location where the actual collapse points. In the study area where damage occurred, the moderate and low grades of the vulnerability of previous hazard map were 12% and 88%, respectively. While, the improved map showed 2% high grade, moderate grade 29%, low grade 66% and very low grade 2%. These results were similar to actual damage. Keywords: hazard map, urban area, soil depth, ground water level Acknowledgement This research was supported by a Grant from a Strategic Research Project (Horizontal Drilling and Stabilization Technologies for Urban Search and Rescue (US&R) Operation) funded by the Korea Institute of Civil Engineering and Building Technology.

  14. Phosphate-Based Mineralization of Arsenic in Contaminated Soil: A Potential Remediation Method for Soil and Groundwater

    Science.gov (United States)

    Neupane, G.; Donahoe, R. J.

    2009-12-01

    Soil arsenic contamination resulting from the use of arsenical compounds is a widespread environmental problem. A phosphate-based remediation method which has the potential to immobilize arsenic in both oxidizing and reducing subsurface systems is under laboratory investigation. Although phosphate treatments have been reported to be effective in removal of arsenic from contaminated water, its use in contaminated soils has not been tested. This study aims to (1) determine the competitive adsorption/desorption of arsenate and phosphate at surfaces of ferric hydroxide coated sand in the absence or presence of calcium ions, and (2) develop a method of arsenic fixation which involves phosphoric acid flushing of arsenic from contaminated soil and precipitation of arsenic as apatite-like phases. Ferric hydroxide is a significant arsenic sequestering constituent in soil. Phosphate competes with arsenate for adsorption sites on the ferric hydroxide surface. Batch adsorption experiments conducted using ferric hydroxide coated sand have indicated similar pH-controlled adsorption mechanisms for both arsenate and phosphate. The data obtained from the adsorption experiments is being used to guide the development of a phosphate-based method for soil and groundwater arsenic remediation. Batch experiments were performed using 3g of contaminated soil in contact with 45 ml of treatment fluid (a dilute phosphoric acid and calcium hydroxide solution). Solution samples were collected at 24, 72, 144, 312, and 384 hours, with continuous agitation at 200 rpm. Solution concentrations of phosphorus and calcium generally decreased with time and were primarily controlled by pH. It has been experimentally demonstrated that solution arsenic concentrations can be lowered by maintaining high pH with adequate calcium supply. A batch experiment conducted at pH > 11, using 1 kg of soil in contact with 1 liter of 0.25% H3PO4, precipitated a white material giving an XRD signature indicative of brushite

  15. Application of ultrasound to textiles washing in aqueous solutions.

    Science.gov (United States)

    Gotoh, Keiko; Harayama, Kokoro

    2013-03-01

    The ultrasound was applied to textile washing as a mechanical action for soil removal. The polyester fabric was soiled with carbon black or oleic acid as a model contaminant, and washed with the original fabric in aqueous solutions without and with alkali or surfactant by applying ultrasound, shaking or stirring action. The detergency and soil redeposition were evaluated from the change in the surface reflectance of artificially soiled fabrics and the original fabric due to washing. In comparison with shaking and stirring actions, ultrasound was found to remove the particulate and oily soils efficiently in a short time and at low bath ratio. With increasing ultrasound power, the detergency of both soils increased and exceeded that obtained with Wascator, a horizontal axis drum type washer. Using three standard fabrics for determining mechanical action during washing, it was shown that ultrasound washing caused little mechanical damage to the fabric. However, the soil redeposition was frequently observed for ultrasonic washing, especially at low bath ratio.

  16. Estimating the Impact of Vadose Zone Sources on Groundwater to Support Performance Assessment of Soil Vapor Extraction

    Energy Technology Data Exchange (ETDEWEB)

    Oostrom, Martinus [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Truex, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rice, Amy K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Christian D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carroll, Kenneth C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Becker, Dave [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Simon, Michelle A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-03-13

    Soil vapor extraction (SVE) is a prevalent remediation approach for volatile contaminants in the vadose zone. To support selection of an appropriate endpoint for the SVE remedy, an evaluation is needed to determine whether vadose zone contamination has been diminished sufficiently to protect groundwater. When vapor-phase transport is an important component of the overall contaminant fate and transport from a vadose zone source, the contaminant concentration expected in groundwater is controlled by a limited set of parameters, including specific site dimensions, vadose zone properties, and source characteristics. An approach was developed for estimating the contaminant concentration in groundwater resulting from a contaminant source in the vadose zone based on pre-modeling contaminant transport for a matrix of parameter value combinations covering a range of potential site conditions. An interpolation and scaling process are then applied to estimate groundwater impact for site-specific conditions.

  17. Nitrate dynamics in the soil and unconfined aquifer in arid groundwater coupled ecosystems of the Monte desert, Argentina

    Science.gov (United States)

    Aranibar, J. N.; Villagra, P. E.; Gomez, M. L.; JobbáGy, E.; Quiroga, M.; Wuilloud, R. G.; Monasterio, R. P.; Guevara, A.

    2011-12-01

    In arid ecosystems, vegetation controls water and nitrate movement in the soil, reducing solute transport to aquifers. Here we analyzed nitrate distribution and transport throughout the soil profile and to the groundwater under different ecologic (vegetation type) and topographic (upland/lowland) situations across sand dune ecosystems with shallow water tables, subject to domestic grazing in the Monte desert. Based on vertical nitrate distributions in deep soil profiles we found that dune uplands (deep groundwater, low productivity) lost relatively more nitrogen than lowlands (shallow groundwater, high productivity), likely reinforcing productivity contrasts along these topographic positions. The traditional practice of nighttime animal concentration in corrals may affect nitrogen transport, with poorly vegetated interdunes at livestock posts showing higher subsoil nitrate concentrations than a well-vegetated nonsettled interdune. Vegetation left its imprint on the vertical distribution of nitrate, as suggested by the presence of a depletion zone that matched the depth of maximum root densities, followed by an underlying zone of accumulation. To explore how nitrogen exports to groundwater could affect water quality and nutrient supply to phreatophyte plants, we characterized groundwater flow patterns based on a potentiometric map and sediment characteristics, and measured groundwater electric conductivity, nitrate and arsenic concentration, and stable isotopes across 29 wells (5.8-12 m deep). Under the present land use and climate conditions, nitrate leaching does not seem to have an important and widespread effect on water quality. Nitrate concentration exceeded established limits for human consumption (45 mg L-1) in only one well, while arsenic concentration exceeded the established limits (10 μg L-1) in all but one well, reaching extreme values of 629 μg L-1. Yet, our analysis suggests that nitrate exports from corrals can reach the aquifer in localized areas

  18. The impact on climate of groundwater induced soil moisture memory : a study with a fully coupled WRF-LEAFHYDRO system

    Science.gov (United States)

    Miguez-Macho, Gonzalo; Gómez, Breogán; Martínez-de la Torre, Alberto

    2014-05-01

    Groundwater dynamics and its interactions with the land-atmosphere system are increasingly being taking into consideration in climate and ecosystem modeling studies. A shallow water table slows down drainage and affects soil moisture and potentially evapotranspiration (ET) and climate, particularly in water-limited environments. Our area of interest, the Iberian Peninsula, with a typical Mediterranean climate of dry growing season, is one of such regions where ET is largely constrained by water availability. We investigate how the induced memory on soil moisture by groundwater affects spring precipitation and summer temperatures there using a fully coupled WRF-LEAFHYDRO system. The LEAFHYDRO Land Surface Model includes groundwater dynamics with a realistic water table validated with hundreds of observations over Spain and Portugal. We perform two sets of long-term offline simulations, with and without groundwater forced by ERA-Interim and detailed precipitation analyses for the Iberian Peninsula. The corresponding fully coupled simulations with the Weather Research and Forecasting model (WRF), using exactly the same grid, take initial conditions from the off-line simulations at the end of the winter and are run for spring and summer, when we expect the impact of ET on climate to be largest. After a dry winter, in the run with groundwater soils are considerably wetter in regions with shallow water table and WRF results indicate that during spring the impact on precipitation can be sizeable when synoptic conditions are favorable for convection. Increased ET in the summer due also to more moisture availability in the run with groundwater leads in general to cooler temperatures. These preliminary results highlight the important role of groundwater on climate and the advantages of a fully coupled hydrology-atmospheric modeling system.

  19. Strengthening Effects of Sodium Salts on Washing Kerosene Contaminated Soil with Surfactants%钠盐类型对表面活性剂清洗煤油污染土壤的强化效应

    Institute of Scientific and Technical Information of China (English)

    黄昭露; 陈泉源; 周娟; 谢墨函

    2015-01-01

    采用表面活性剂清洗煤油污染土壤,考察添加钠盐对洗脱率的影响,并用 Zeta 电位仪、表面张力仪对溶液及用接触角仪对清洗前后的土壤进行表征。结果表明,硅酸钠对十二烷基硫酸钠(SDS)清洗的增效作用最明显;酒石酸钠对十二烷基苯磺酸钠(SDBS)及聚氧乙烯月桂醚(Brij35)清洗的增效作用最明显;不同类型钠盐对曲拉通 X-100(TX-100)清洗均有一定的增效作用但差别不明显;腐殖酸钠及硅酸钠对皂苷溶液清洗的增效程度相当,但就改良土质而言选用腐殖酸钠作助剂更为合适;硅酸钠对 Tw-80清洗的增效作用随着 Tw-80浓度的增大而增强,氯化钠和酒石酸钠则相反。钠盐增效清洗的作用机制是降低离子型表面活性剂的表面张力和临界胶束浓度;而非离子型表面活性剂的增效作用则是利用钠盐防止煤油“重吸附”及抗表面活性剂“沉淀”,增大胶团体积来实现。接触角测量表明,煤油污染后的土壤亲水性减弱,清洗后接触角变小,亲水性增强,且随着表面活性剂浓度的增大接触角减小,对恢复土壤运输水分和养料正常功能有利。%The impact of sodium salt on kerosene contaminated soil washing with surfactants was investigated. The results indicated that sodium silicate greatly enhanced the washing efficiency of SDS. Sodium tartrate can largely enhance the washing efficiency of SDBS and Brij35. Sodium salts can enhance the washing efficiency on kerosene contaminated with TX- 100. No significant differences were observed between different sodium salts. Sodium salt of humic acid and sodium silicate had similar enhancement on kerosene contaminated soil washing with saponin. Sodium humate can be a better choice since its application can also improve soil quality. The enhancement of sodium silicate on kerosene contaminated soil washing with Tw- 80 increased with the increase of Tw- 80 dosage

  20. Performance of in-situ soil and groundwater treatment systems at McClellan Air Force Base

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, T.E. [BDM Federal, McClellan AFB, CA (United States); Mook, P.H. Jr.; Wong, K.B. [Sm-ALC/EMR, McClellan AFB, CA (United States)

    1997-12-31

    McClellan Air Force Base (AFB), located near Sacramento, California, is one of the Strategic Environmental Research and Development Program`s National Environmental Technology Test Sites. The US Air Force has evaluated, as part of the on-going environmental clean-up of McClellan AFB, several innovative and conventional in situ soil and groundwater technologies for the treatment of volatile organic compounds. This paper presents an overview and comparison of the performance and cost of three innovative technologies tested at McClellan AFB. Conventional groundwater extraction systems are effective but costly. Operation and maintenance (O and M) costs for treatment systems are increasingly becoming a major component of the environmental clean-up budget. The performance, limitations, costs, and lessons learned from the implementation of conventional soil vapor and groundwater extraction systems are compared with those of two innovative dual phase extraction systems. Both the Xerox 2-Phase{trademark} Extraction system and a standard dual phase extraction system are more effective than their conventional counterparts, but only over a discrete range of soil permeabilities. Discussions on McClellan AFB`s experiences with cometabolic bioremediation of groundwater and thermally enhanced soil vapor extraction systems are also included.

  1. Calibrating a large-extent high-resolution coupled groundwater-land surface model using soil moisture and discharge data

    NARCIS (Netherlands)

    Sutanudjaja, E.H.; Beek, L.P.H. van; Jong, S.M. de; Geer, F.C. van; Bierkens, M.F.P.

    2014-01-01

    We explore the possibility of using remotely sensed soil moisture data and in situ discharge observations to calibrate a large-extent hydrological model. The model used is PCR-GLOBWB-MOD, which is a physically based and fully coupled groundwater-land surface model operating at a daily basis and havi

  2. Contamination of soils and groundwater by hydrocarbons release. Contaminacion de suelos y aguas subterraneas por fugas de hidrocarburos

    Energy Technology Data Exchange (ETDEWEB)

    Muzikar, R.; Rogel Quesada, J.M.

    1993-01-01

    The article describes the fundamentals driving the transfer of hydrocarbons at the geological media, the state of the art on contamination R and D and decontamination technologies for both soils and groundwater. A real example is given located at the Slovnaft Refinery in Bratislava (Slovakia). (Author)

  3. Landscape structure, groundwater dynamics, and soil water content influence soil respiration across riparian-hillslope transitions in the Tenderfoot Creek Experimental Forest, Montana

    Science.gov (United States)

    Vincent J. Pacific; Brian L. McGlynn; Diego A. Riveros-Iregui; Daniel L. Welsch; Howard E. Epstein

    2011-01-01

    Variability in soil respiration at various spatial and temporal scales has been the focus of much research over the last decade aimed to improve our understanding and parameterization of physical and environmental controls on this flux. However, few studies have assessed the control of landscape position and groundwater table dynamics on the spatiotemporal variability...

  4. In situ denitrification and DNRA rates in soils and underlying groundwater of an integrated constructed wetland

    Science.gov (United States)

    Mofizur Rahman Jahangir, Mohammad; Fenton, Owen; McAleer, Eoin; Carroll, Paul; Harrington, Rory; Johnston, Paul; Müller, Christoph; Richards, Karl

    2015-04-01

    Nitrogen (N) removal efficiency in constructed wetlands (CW) is low and again it does not in itself explain whether the removed N species are reactive or benign. Evaluation of environmental benefits of CW necessitates knowing N removal mechanisms and the fate of the removed N in such system. In situ denitrification and DNRA (dissimilatory nitrate reduction to ammonium) rates were measured in an earthen lined 5-cell integrated CW using 15N-enriched nitrate (NO3--N) push-pull method. Measurements were conducted in 2 groundwater depths (shallow- soils in CW bed; and deep- 4 m below CW soils) in 2 contrasting cells (high vs. low nutrient loads) of the CW. Denitrification (N¬2O-N + N2-N) and DNRA were the major NO3--N removal processes accounting together for 54-79% of the total biochemical removal of the applied NO3--N. Of which 14-17 and 40-68% were removed by denitrification and DNRA, respectively. Both the processes significantly differed with CW cells indicating that N transformations depend on the rate of nutrient loads in different cells. They were significantly higher in shallow than deep groundwater. Environmental conditions were favourable for both the processes (i.e. low dissolved oxygen and low redox potential, high dissolved organic carbon, high total carbon and high dissolved organic N) but DNRA rate was favoured over denitrification by high ambient NH4+ concentrations, reduced sulphide and low pH (5.9 - 7.0). Low pH might have limited denitrification to some extent to an incomplete state, being evident by a high N2O-N/(N2O-N+N2-N) ratio (0.35 ± 0.17, SE). Relatively higher N2O-N/(N2O-N+N2-N) ratio and higher DNRA rate over denitrification suggest that the end products of N transformations are reactive. This N2O can be consumed to N2 and/or emit to atmosphere directly and indirectly. The DNRA rate and accumulation of NH4+ indicated that CW is a net source of NH4+ in groundwater. Ammonium produced by DNRA can be fixed in soils and, when exchange sites are

  5. Nitrate Remediation of Soil and Groundwater Using Phytoremediation: Transfer of Nitrogen Containing Compounds from the Subsurface to Surface Vegetation

    Science.gov (United States)

    Nelson, Sheldon

    2013-04-01

    Nitrate Remediation of Soil and Groundwater Using Phytoremediation: Transfer of Nitrogen Containing Compounds from the Subsurface to Surface Vegetation Sheldon Nelson Chevron Energy Technology Company 6001 Bollinger Canyon Road San Ramon, California 94583 snne@chevron.com The basic concept of using a plant-based remedial approach (phytoremediation) for nitrogen containing compounds is the incorporation and transformation of the inorganic nitrogen from the soil and/or groundwater (nitrate, ammonium) into plant biomass, thereby removing the constituent from the subsurface. There is a general preference in many plants for the ammonium nitrogen form during the early growth stage, with the uptake and accumulation of nitrate often increasing as the plant matures. The synthesis process refers to the variety of biochemical mechanisms that use ammonium or nitrate compounds to primarily form plant proteins, and to a lesser extent other nitrogen containing organic compounds. The shallow soil at the former warehouse facility test site is impacted primarily by elevated concentrations of nitrate, with a minimal presence of ammonium. Dissolved nitrate (NO3-) is the primary dissolved nitrogen compound in on-site groundwater, historically reaching concentrations of 1000 mg/L. The initial phases of the project consisted of the installation of approximately 1750 trees, planted in 10-foot centers in the areas impacted by nitrate and ammonia in the shallow soil and groundwater. As of the most recent groundwater analytical data, dissolved nitrate reductions of 40% to 96% have been observed in monitor wells located both within, and immediately downgradient of the planted area. In summary, an evaluation of time series groundwater analytical data from the initial planted groves suggests that the trees are an effective means of transfering nitrogen compounds from the subsurface to overlying vegetation. The mechanism of concentration reduction may be the uptake of residual nitrate from the

  6. Uranium geochemistry in soil and groundwater at the F and H seepage basins

    Energy Technology Data Exchange (ETDEWEB)

    Serkiz, S.M.; Johnson, W.H.

    1994-09-01

    For 33 years, low activity liquid wastes from the chemical separation areas at the U.S. Department of Energy`s Savannah River Site were disposed of in unlined seepage basins. Soil and associated pore water samples of widely varying groundwater chemistries and contaminant concentrations were collected from the region downgradient of these basins using cone penetrometer technology. Analysis of samples using inductively coupled plasma - mass spectrometry has allowed the investigation of uranium partitioning between the aqueous phase and soil surfaces at this site. The distribution of uranium was examined with respect to the solution and soil chemistry (e.g., pH, redox potential, cation and contaminant concentration) and aqueous-phase chemical speciation modeling. The uranium soil source term at the F- and H-Area Seepage Basins (FHSB) is much smaller than has been used in previous modeling efforts. This should result in a much shorter remediation time and a greater effectiveness of a pump-and-treat design than previously predicted. Distribution coefficients at the (FHSB) were found to vary between 1.2 to 34,000 1 kg{sup {minus}1} for uranium. Differences in sorption of these elements can be explained primarily by changes in aqueous pH and the associated change in soil surface charge. Sorption models were fit directly to sorption isotherms from field samples. All models underestimated the fraction of uranium bound at low aqueous uranium concentrations. Linear models overestimated bound uranium at locations where the aqueous concentration was greater than 500 ppb. Mechanistic models provided a much better estimate of the bound uranium concentrations, especially at high aqueous concentrations. Since a large fraction of the uranium at the site is associated with the low-pH portion of the plume, consideration should be given to pumping water from the lowest pH portions of the plume in the F-Area.

  7. China's soil and groundwater management challenges: Lessons from the UK's experience and opportunities for China.

    Science.gov (United States)

    Coulon, Frédéric; Jones, Kevin; Li, Hong; Hu, Qing; Gao, Jingyang; Li, Fasheng; Chen, Mengfang; Zhu, Yong-Guan; Liu, Rongxia; Liu, Ming; Canning, Kate; Harries, Nicola; Bardos, Paul; Nathanail, Paul; Sweeney, Rob; Middleton, David; Charnley, Maggie; Randall, Jeremy; Richell, Martin; Howard, Trevor; Martin, Ian; Spooner, Simon; Weeks, Jason; Cave, Mark; Yu, Fang; Zhang, Fang; Jiang, Ying; Longhurst, Phil; Prpich, George; Bewley, Richard; Abra, Jonathan; Pollard, Simon

    2016-05-01

    There are a number of specific opportunities for UK and China to work together on contaminated land management issues as China lacks comprehensive and systematic planning for sustainable risk based land management, encompassing both contaminated soil and groundwater and recycling and reuse of soil. It also lacks comprehensive risk assessment systems, structures to support risk management decision making, processes for verification of remediation outcome, systems for record keeping and preservation and integration of contamination issues into land use planning, along with procedures for ensuring effective health and safety considerations during remediation projects, and effective evaluation of costs versus benefits and overall sustainability. A consequence of the absence of these overarching frameworks has been that remediation takes place on an ad hoc basis. At a specific site management level, China lacks capabilities in site investigation and consequent risk assessment systems, in particular related to conceptual modelling and risk evaluation. There is also a lack of shared experience of practical deployment of remediation technologies in China, analogous to the situation before the establishment of the independent, non-profit organisation CL:AIRE (Contaminated Land: Applications In Real Environments) in 1999 in the UK. Many local technology developments are at lab-scale or pilot-scale stage without being widely put into use. Therefore, a shared endeavour is needed to promote the development of technically and scientifically sound land management as well as soil and human health protection to improve the sustainability of the rapid urbanisation in China.

  8. Jet grouting for a groundwater cutoff wall in difficult glacial soil deposits

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, R.F.; Pepe, F. Jr. [Parsons Brinckerhoff Quade & Douglas, New York, NY (United States)

    1997-12-31

    Jet grouting is being used as part of a groundwater cutoff wall system in a major New York City subway construction project to limit drawdowns in an adjacent PCB contamination plume. A circular test shaft of jet grout columns was conducted during the design phase to obtain wall installation parameters. The test program also included shaft wall mapping, and measurements of; inflows, piezometric levels, ground heave and temperature, and jet grout hydraulic conductivity. An axisymmetric finite element method groundwater model was established to back calculate the in-situ hydraulic conductivities of both the surrounding glacial soils and the jet grout walls by matching observed inflows and piezometric levels. The model also verified the use of packer permeability test as a tool in the field to evaluate the hydraulic conductivities of jet grout columns. Both the test program and analytic studies indicated that adjustments to the construction procedures would be required to obtain lower hydraulic conductivities of the jet grout walls for construction. A comparison is made with the conductivities estimated from the test program/analytic studies with those from the present construction.

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

    Energy Technology Data Exchange (ETDEWEB)

    Paul Fallgren

    2009-02-10

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

  10. Soil and groundwater VOCs contamination: How can electrical geophysical measurements help assess post-bioremediation state?

    Science.gov (United States)

    Kessouri, P.; Johnson, T. C.; Day-Lewis, F. D.; Slater, L. D.; Ntarlagiannis, D.; Johnson, C. D.

    2016-12-01

    The former Brandywine MD (Maryland, USA) Defense Reutilization and Marketing Office (DRMO) was designated a hazardous waste Superfund site in 1999. The site was used as a storage area for waste and excess government equipment generated by several U.S. Navy and U.S. Air Force installations, leading to soil and groundwater contamination by volatile organic compounds (VOCs). Active bioremediation through anaerobic reductive dehalogenation was used to treat the groundwater and the aquifer unconsolidated materials in 2008, with electrical geophysical measurements employed to track amendment injections. Eight years later, we used spectral induced polarization (SIP) and time domain induced polarization (TDIP) on 2D surface lines and borehole electrical arrays to assess the long term impact of active remediation on physicochemical properties of the subsurface. Within the aquifer, the treated zone is more electrically conductive, and the phase shift describing the polarization effects is higher than in the untreated zone. Bulk conductivity and phase shift are also locally elevated close to the treatment injection well, possibly due to biogeochemical transformations associated with prolonged bacterial activity. Observed SIP variations could be explained by the presence of biofilms coating the pore space and/or by-products of the chemical reactions catalyzed by the bacterial activity (e.g. iron sulfide precipitation). To investigate these possibilities, we conducted complementary well logging measurements (magnetic susceptibility [MS], nuclear magnetic resonance [NMR], gamma-ray) using 5 boreholes installed at both treated and untreated locations of the site. We also collected water and soil samples on which we conducted microbiological and chemical analyses, along with geophysical observations (SIP, MS and NMR), in the laboratory. These measurements provide further insights into the physicochemical transformations in the subsurface resulting from the treatment and highlight

  11. Environmental impacts on soil and groundwater at airports: origin, contaminants of concern and environmental risks.

    Science.gov (United States)

    Nunes, L M; Zhu, Y-G; Stigter, T Y; Monteiro, J P; Teixeira, M R

    2011-11-01

    Environmental impacts of airports are similar to those of many industries, though their operations expand over a very large area. Most international impact assessment studies and environmental management programmes have been giving less focus on the impacts to soil and groundwater than desirable. This may be the result of the large attention given to air and noise pollution, relegating other environmental descriptors to a second role, even when the first are comparatively less relevant. One reason that contributes to such "biased" evaluation is the lack of systematic information about impacts to soil and groundwater from airport activities, something the present study intends to help correct. Results presented here include the review of over seven hundred documents and online databases, with the objective of obtaining the following information to support environmental studies: (i) which operations are responsible for chemical releases?; (ii) where are these releases located?; (iii) which contaminants of concern are released?; (iv) what are the associated environmental risks? Results showed that the main impacts occur as a result of fuel storage, stormwater runoff and drainage systems, fuel hydrant systems, fuel transport and refuelling, atmospheric deposition, rescue and fire fighting training areas, winter operations, electrical substations, storage of chemical products by airport owners or tenants, and maintenance of green areas. A new method for ranking environmental risks of organic substances, based on chemical properties, is proposed and applied. Results show that the contaminants with the highest risks are the perfluorochemicals, benzene, trichloroethylene and CCl(4). The obtained information provides a basis for establishing the planning and checking phases of environmental management systems, and may also help in the best design of pollution prevention measures in order to avoid or reduce significant environmental impacts from airports.

  12. Screening-level risk assessment for styrene-acrylonitrile (SAN) trimer detected in soil and groundwater.

    Science.gov (United States)

    Kirman, C R; Gargas, M L; Collins, J J; Rowlands, J C

    2012-01-01

    A screening-level risk assessment was conducted for styrene-acrylonitrile (SAN) Trimer detected at the Reich Farm Superfund site in Toms River, NJ. Consistent with a screening-level approach, on-site and off-site exposure scenarios were evaluated using assumptions that are expected to overestimate actual exposures and hazards at the site. Environmental sampling data collected for soil and groundwater were used to estimate exposure point concentrations. Several exposure scenarios were evaluated to assess potential on-site and off-site exposures, using parameter values for exposures to soil (oral, inhalation of particulates, and dermal contact) and groundwater (oral, dermal contact) to reflect central tendency exposure (CTE) and reasonable maximum exposure (RME) conditions. Three reference dose (RfD) values were derived for SAN Trimer for short-term, subchronic, and chronic exposures, based upon its effects on the liver in exposed rats. Benchmark (BMD) methods were used to assess the relationship between exposure and response, and to characterize appropriate points of departure (POD) for each RfD. An uncertainty factor of 300 was applied to each POD to yield RfD values of 0.1, 0.04, and 0.03 mg/kg-d for short-term, subchronic, and chronic exposures, respectively. Because a chronic cancer bioassay for SAN Trimer in rats (NTP 2011a) does not provide evidence of carcinogenicity, a cancer risk assessment is not appropriate for this chemical. Potential health hazards to human health were assessed using a hazard index (HI) approach, which considers the ratio of exposure dose (i.e., average daily dose, mg/kg-d) to toxicity dose (RfD, mg/kg-d) for each scenario. All CTE and RME HI values are well below 1 (where the average daily dose is equivalent to the RfD), indicating that there is no concern for potential noncancer effects in exposed populations even under the conservative assumptions of this screening-level assessment.

  13. Potential groundwater recharge for the State of Minnesota using the Soil-Water-Balance model, 1996-2010

    Science.gov (United States)

    Smith, Erik A.; Westenbroek, Stephen M.

    2015-01-01

    Groundwater recharge is one of the most difficult components of a water budget to ascertain, yet is an important boundary condition necessary for the quantification of water resources. In Minnesota, improved estimates of recharge are necessary because approximately 75 percent of drinking water and 90 percent of agricultural irrigation water in Minnesota are supplied from groundwater. The water that is withdrawn must be supplied by some combination of (1) increased recharge, (2) decreased discharge to streams, lakes, and other surface-water bodies, and (3) removal of water that was stored in the system. Recent pressure on groundwater resources has highlighted the need to provide more accurate recharge estimates for various tools that can assess the sustainability of long-term water use. As part of this effort, the U.S. Geological Survey, in cooperation with the Minnesota Pollution Control Agency, used the Soil-Water-Balance model to calculate gridded estimates of potential groundwater recharge across Minnesota for 1996‒2010 at a 1-kilometer (0.621-mile) resolution. The potential groundwater recharge estimates calculated for Minnesota from the Soil-Water Balance model included gridded values (1-kilometer resolution) of annual mean estimates (that is, the means for individual years from 1996 through 2010) and mean annual estimates (that is, the mean for the 15-year period 1996−2010).

  14. Linking soil moisture balance and source-responsive preferential flow models for estimating groundwater recharge

    Science.gov (United States)

    Cuthbert, M. O.; Mackay, R.; Nimmo, J. R.

    2012-04-01

    Results are presented of a detailed study into the vadose zone and shallow water table hydrodynamics of a fieldsite in Shropshire, UK. Tensiometry reveals that the loamy sand topsoil wets up via macropore flow and subsequent redistribution of moisture into the soil matrix. However, recharge does not occur until near-positive pressures are achieved at the top of the glaciofluvial outwash material that underlies the topsoil, about 1 m above the water table. Once this occurs, very rapid water table rises follow. This threshold behaviour is attributed to the vertical discontinuity in the macropore system due to seasonal ploughing of the topsoil, and a lower permeability plough/iron pan restricting matrix flow between the topsoil and the lower outwash deposits. Thus, although the wetting process in the topsoil is highly complex, a soil moisture balance model (SMBM) is shown to be skilful in predicting the initiation of preferential flow from the base of the topsoil into the lower outwash horizon. The rapidity of the response at the water table suggests that Stokes type film flow rather than Richards type capillarity dominated flow is occurring and this conjecture is tested using a range of numerical models. A variation of the source-responsive model proposed by Nimmo (2010) is shown to reproduce the observed water table dynamics well, when linked to a SMBM as the source of recharge from the topsoil. The results reveal new insights into preferential flow processes in cultivated soils. If the conceptual and numerical models can be shown to be transferable to other ploughed soils, it promises to be a very useful and practical approach to accounting for preferential flow in studies of groundwater recharge estimation. Nimmo, J. R. (2010). Theory for Source-Responsive and Free-Surface Film Modeling of Unsaturated Flow. Vadose Zone Journal, 9, 295-306.

  15. Preparation of soil stained strips for the evaluation of washing machine performance%洗衣机净洗能力检测用泥渍污染布的制备及性能评价

    Institute of Scientific and Technical Information of China (English)

    蒋黎; 朱小雷; 王强; 范雪荣

    2015-01-01

    Soil stained test strips for the test of washing performance of washing machine were prepared with carbon black/clay.The effect of dosage of Peregal O on the stability of carbon black solution and that of sodium hexametaphosphate ( SHMP) on the stability of clay dispersion solution were analyzed respectively. The stability of soil stained solution was studied after that.Furthermore, the evenness, storage stability and washing performance of the soil stained strips were all evaluated.The results indicate that stable carbon black solution and clay dispersion solution are obtained when the dosage of Peregal O and SHMP are both 1 .6%.The stability of homogeneous soil stained solution can be kept for at least 8 h. The self-made soil stained strips show excellent evenness, storage stability and washing performance.%采用炭黑/黏土制备泥渍污染布。分别探讨平平加O及六偏磷酸钠( SHMP)用量对炭黑、黏土分散液稳定性的影响;研究泥渍污液的稳定性,评价所制备的泥渍污染布的均匀性、贮存稳定性及洗涤性能。结果表明,当平平加O与SHMP质量分数均为1.6%时,炭黑分散液与黏土分散液最稳定,泥渍污液静置8h后依然稳定性良好。所制备的泥渍污染布表面沾污均匀,具有良好的贮存稳定性和适当的净洗性能。

  16. The comparative photodegradation activities of pentachlorophenol (PCP and polychlorinated biphenyls (PCBs using UV alone and TiO2-derived photocatalysts in methanol soil washing solution.

    Directory of Open Access Journals (Sweden)

    Zeyu Zhou

    Full Text Available Photochemical treatment is increasingly being applied to remedy environmental problems. TiO2-derived catalysts are efficiently and widely used in photodegradation applications. The efficiency of various photochemical treatments, namely, the use of UV irradiation without catalyst or with TiO2/graphene-TiO2 photodegradation methods was determined by comparing the photodegadation of two main types of hydrophobic chlorinated aromatic pollutants, namely, pentachlorophenol (PCP and polychlorinated biphenyls (PCBs. Results show that photodegradation in methanol solution under pure UV irradiation was more efficient than that with either one of the catalysts tested, contrary to previous results in which photodegradation rates were enhanced using TiO2-derived catalysts. The effects of various factors, such as UV light illumination, addition of methanol to the solution, catalyst dosage, and the pH of the reaction mixture, were examined. The degradation pathway was deduced. The photochemical treatment in methanol soil washing solution did not benefit from the use of the catalysts tested. Pure UV irradiation was sufficient for the dechlorination and degradation of the PCP and PCBs.

  17. The comparative photodegradation activities of pentachlorophenol (PCP) and polychlorinated biphenyls (PCBs) using UV alone and TiO2-derived photocatalysts in methanol soil washing solution.

    Science.gov (United States)

    Zhou, Zeyu; Zhang, Yaxin; Wang, Hongtao; Chen, Tan; Lu, Wenjing

    2014-01-01

    Photochemical treatment is increasingly being applied to remedy environmental problems. TiO2-derived catalysts are efficiently and widely used in photodegradation applications. The efficiency of various photochemical treatments, namely, the use of UV irradiation without catalyst or with TiO2/graphene-TiO2 photodegradation methods was determined by comparing the photodegadation of two main types of hydrophobic chlorinated aromatic pollutants, namely, pentachlorophenol (PCP) and polychlorinated biphenyls (PCBs). Results show that photodegradation in methanol solution under pure UV irradiation was more efficient than that with either one of the catalysts tested, contrary to previous results in which photodegradation rates were enhanced using TiO2-derived catalysts. The effects of various factors, such as UV light illumination, addition of methanol to the solution, catalyst dosage, and the pH of the reaction mixture, were examined. The degradation pathway was deduced. The photochemical treatment in methanol soil washing solution did not benefit from the use of the catalysts tested. Pure UV irradiation was sufficient for the dechlorination and degradation of the PCP and PCBs.

  18. Granular activated carbon adsorption and microwave regeneration for the treatment of 2,4,5-trichlorobiphenyl in simulated soil-washing solution

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xitao [Persistent Organic Pollutants Research Centre, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China); Yu Gang [Persistent Organic Pollutants Research Centre, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China)]. E-mail: yg-den@tsinghua.edu.cn; Han Wenya [Persistent Organic Pollutants Research Centre, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2007-08-25

    The treatment of 2,4,5-trichlorobiphenyl (PCB29) in simulated soil-washing solution by granular activated carbon (GAC) adsorption and microwave (MW) regeneration was investigated in this study. The PCB29 adsorption process was carried out in a continuous flow adsorption column. After adsorption, the PCB29-loaded GAC was dried at 103 deg. C, and regenerated in a quartz reactor by 2450 MHz MW irradiation at 700 W for 5 min. The efficacy of this procedure was analyzed by determining the rates and amounts of PCB29 adsorbed in successive adsorption/MW regeneration cycles. Effects of the regeneration on the textural properties and the PCB29 adsorption capacity of GAC were examined. It was found that after several adsorption/MW regeneration cycles, the adsorption rate of GAC increased, whereas, the adsorption capacity decreased, which could be explained according to the change of textural properties. Most of the PCB29 adsorbed on GAC was degraded within 3 min under MW irradiation, and the analysis of degradation products by GC-MS demonstrated that PCB29 experienced dechlorination during this treatment.

  19. Groundwater dynamics in wetland soils control the production and transfer mechanisms of dissolved reactive phosphorus in an agricultural landscape

    Science.gov (United States)

    Dupas, Rémi; Gu, Sen; Gruau, Gérard; Gascuel-Odoux, Chantal

    2015-04-01

    Because of its high sorption affinity on soils solid phase, mitigation options to reduce diffuse P transfer usually focus on trapping particulate P forms delivered via surface flowpaths. Therefore, vegetated buffer zones placed between croplands and watercourses have been promoted worldwide, sometimes in wetland areas. To investigate the risk of such P trapping riparian wetlands (RWs) releasing dissolved P to rivers, we monitored molybdate reactive P (MRP) in the free soil solution of two RWs in an intensively farmed catchment. Two main mechanisms causing MRP release were identified in light of the geochemical and hydrological conditions in the RWs, controlled by groundwater dynamics. First, soil rewetting after the dry summer was associated with the presence of a pool of mobile P, limited in size. Its mobilization started under conditions of water saturation caused by groundwater uprise in RW organo-mineral soil horizons. Second, the establishment of anoxic conditions in the end of the winter caused reductive solubilization of Fe oxide-hydroxide, along with release of P. Comparison between sites revealed that the first MRP release occurred only in a RW with P enriched soils, whereas the second was recorded even in a RW with a low soil P status. Seasonal variations in MRP concentrations in the stream were synchronized with those in RW soils. Hence, enriched and/or periodically anoxic RWs can act as a key component of the P transfer continuum in agricultural landscapes by converting particulate P from croplands into MRP released to rivers.

  20. Occurrence and treatment of arsenic in groundwater and soil in northern Mexico and southwestern USA.

    Science.gov (United States)

    Camacho, Lucy Mar; Gutiérrez, Mélida; Alarcón-Herrera, Maria Teresa; Villalba, Maria de Lourdes; Deng, Shuguang

    2011-04-01

    This review focuses on the occurrence and treatment of arsenic (As) in the arid region of northern Mexico (states of Chihuahua and Coahuila) and bordering states of the southwestern US (New Mexico, Arizona, and Texas), an area known for having high As concentrations. Information assembled and assessed includes the content and probable source of As in water, soil, and sediments and treatment methods that have been applied in the area. High As concentrations were found mainly in groundwater, their source being mostly from natural origin related to volcanic processes with significant anthropogenic contributions near mining and smelting of ores containing arsenic. The affinity of As for solid phases in alkaline conditions common to arid areas precludes it from being present in surface waters, accumulating instead in sediments and shifting its threat to its potential remobilization in reservoir sediments and irrigation waterways. Factors such as oxidation and pH that affect the mobility of As in the subsurface environment are mentioned. Independent of socio-demographic variables, nutritional status, and levels of blood lead, cognitive development in children is being affected when exposed to As. Treatments known to effectively reduce As content to safe drinking water levels as well as those that are capable of reducing As content in soils are discussed. Besides conventional methods, emergent technologies, such as phytoremediation, offer a viable solution to As contamination in drinking water.

  1. Uncertainty in 14C model ages of groundwater: The influence of soil gas in terranes dominated by C3 plants

    Science.gov (United States)

    Nelson, S.; Hart, R.; Eggett, D.

    2009-12-01

    Groundwater is the largest source of fresh water readily available to humanity and aquifers with long residence times are particularly susceptible to overuse. Thus, it is important to have quantitative estimates of the residence time of water in such aquifers. Many models used to calculate 14C ages of groundwater depend on an estimate of the δ13C value of carbon dioxide in soil at the time of recharge, a value that must be estimated. Other work has suggested that for terranes dominated by C3 plants, -23‰ is an appropriate value, and sensitivity calculations show that the apparent age of a groundwater is strongly dependent on the choice of this parameter. This is especially true where the measured values of δ13C of dissolved inorganic carbon (DIC) are used to estimate the contribution of “dead” carbon to the DIC load via the dissolution of calcite in the aquifer and soil zones. To better understand the temporal and spatial isotopic and abundance variability of soil carbon dioxide, we established soil gas sampling sites that encompassed a wide variety of settings in terms of season, elevation, climate, and plant community that were sampled monthly throughout regions of the state of Utah where C3 flora dominate. Direct measurements of soil gas suggest a value of -21.8 ± 1.4‰ (1σ) is a good input variable as long as: a) C3 vegetation dominates, and b) extreme aridity does not prevail such that plant densities and soil microbial activities are minimized. If recharge is envisaged to occur during spring and early summer in highly vegetated uplands, a value of -24.0 ± 0.6‰ may be more appropriate as statistical analysis reveals that seasonality and plant density are most clearly correlated to the carbon isotope composition of carbon dioxide in soil gas. Although the two values and ranges cited above values do not diverge strongly from other published estimates, they place fairly narrow limits on the uncertainty of ±500 and ±200 yr., respectively, in

  2. Documentation of input datasets for the soil-water balance groundwater recharge model of the Upper Colorado River Basin

    Science.gov (United States)

    Tillman, Fred D

    2015-01-01

    The Colorado River and its tributaries supply water to more than 35 million people in the United States and 3 million people in Mexico, irrigating more than 4.5 million acres of farmland, and generating about 12 billion kilowatt hours of hydroelectric power annually. The Upper Colorado River Basin, encompassing more than 110,000 square miles (mi2), contains the headwaters of the Colorado River (also known as the River) and is an important source of snowmelt runoff to the River. Groundwater discharge also is an important source of water in the River and its tributaries, with estimates ranging from 21 to 58 percent of streamflow in the upper basin. Planning for the sustainable management of the Colorado River in future climates requires an understanding of the Upper Colorado River Basin groundwater system. This report documents input datasets for a Soil-Water Balance groundwater recharge model that was developed for the Upper Colorado River Basin.

  3. 曝气强化非离子表面活性剂洗涤法修复柴油污染土壤%Remediation of diesel-contaminated soil by aeration enhanced washing with nonionic surfactant

    Institute of Scientific and Technical Information of China (English)

    汤志涛; 陈泉源

    2016-01-01

    The diesel-contaminated soil was remediated by ex-situ aeration enhanced washing method with nonionic surfactant. The factors affecting the washing effect were investigated,and the washing mechanism was studied by determination of surface tension and contact angle. The experimental results show that:The washing effect of diesel oil from diesel-contaminated soil can be enhanced by aeration and the removal rate of diesel oil is increased by 10%-20%;The order of washing effect by 3 kinds of nonionic surfactants is Brij-35>TX-100>Tw-80;Under the optimum conditions of Brij-35 concentration one time of CMC,aeration rate 7.5 L/min,washing time 60 mine and washing solution pH 11.0,the removal rate of diesel oil is 77.4%,the oil content of the diesel-contaminated soil is decreased from 7.0%to 1.6%,the contact angle is decreased from 24.12° to 6.65°,and the hydrophily of the soil can be recovered after washing;The surface tension of the washing solution is decreased with the increase of surfactant concentration,but not affected by washing solution pH.%采用异位修复法,利用非离子表面活性剂洗涤柴油污染土壤,并在洗涤过程中曝气强化。考察了洗涤效果的影响因素,并通过表面张力和接触角的测定探讨了洗涤机理。实验结果表明:曝气对污染土壤中柴油的洗脱有强化作用,可提高洗脱率10%~20%;3种非离子表面活性剂的洗脱效果优劣次序为聚氧乙烯月桂醚(Brij-35)>曲拉通X-100(TX-100)>吐温-80(Tw-80);在表面活性剂浓度为1倍临界胶束浓度、曝气量为7.5 L/min、洗涤时间为60 min、洗涤液pH为11.0的优化条件下,Brij-35对柴油的洗脱率达77.4%,污染土样的含油率从7.0%降至1.6%,接触角从24.12°降至6.65°,可基本恢复土壤的亲水性;洗涤液的表面张力随表面活性剂浓度的增加而降低,但不受洗涤液pH的影响。

  4. Modelling Urban diffuse pollution in groundwater

    Science.gov (United States)

    Jato, Musa; Smith, Martin; Cundy, Andrew

    2017-04-01

    Diffuse urban pollution of surface and ground waters is a growing concern in many cities and towns. Traffic-derived pollutants such as salts, heavy metals and polycyclic aromatic hydrocarbons (PAHs) may wash off road surfaces in soluble or particulate forms which later drain through soils and drainage systems into surface waters and groundwater. In Brighton, about 90% of drinking water supply comes from groundwater (derived from the Brighton Chalk block). In common with many groundwater sources the Chalk aquifer has been relatively extensively monitored and assessed for diffuse rural contaminants such as nitrate, but knowledge on the extent of contamination from road run-off is currently lacking. This project examines the transfer of traffic-derived contaminants from the road surface to the Chalk aquifer, via urban drainage systems. A transect of five boreholes have been sampled on a monthly basis and groundwater samples analysed to examine the concentrations of key, mainly road run-off derived, hydrocarbon and heavy metal contaminants in groundwater across the Brighton area. Trace concentrations of heavy metals and phenols have been observed in groundwater. Electrical conductivity changes in groundwater have also been used to assess local changes in ionic strength which may be associated with road-derived contaminants. This has been supplemented by systematic water and sediment sampling from urban gully pots, with further sampling planned from drainage and settlement ponds adjacent to major roads, to examine initial road to drainage system transport of major contaminants.

  5. 重金属污染土壤修复及其对作物效应%The Remediation of Heavy Metals Polluted Soil by Washing with Chemicals and its Effects on Crops

    Institute of Scientific and Technical Information of China (English)

    莫良玉; 范稚莲; 梁俊; 范业赓

    2011-01-01

    为了探讨不同的淋洗剂修复重金属污染的土壤效果,笔者研究利用水、石灰水、EDTA溶液、水+石灰水(即先用水淋洗后,再用石灰水淋洗)、水+石灰水+EDTA溶液(即先用水淋洗后,再用石灰水淋洗,最后用EDTA溶液淋洗)等5种淋洗方法处理尾矿重金属严重污染的土壤.结果表明:水、石灰水以及EDTA溶液等均能提取污染土壤中的重金属,其中EDTA提取的能力最强,水其次,而石灰水最弱;水稻、玉米、大豆和南瓜等4种作物在不经过修复的污染土壤上不能正常发芽生长,而在修复后的土壤上都能正常发芽,但水处理和EDTA溶液处理的土壤,种子发芽后很快死亡,而其他处理的作物仍可继续生长;石灰水或水+石灰水处理的土壤,作物生物量较高;在污染土壤上生长的作物均能吸收重金属,其中大豆和水稻吸收能力较强.这些结果表明,可以利用石灰来修复重金属尾矿污染的土壤,在修复的土壤上生长的大豆和水稻重金属含量较高,在作物布局上要尽量避免种植这2种作物.%In order to research the effects of remedying heavy metal polluted soil with washing chemicals, the heavy metal polluted soil, on where plants were not able to grow, was remedied by chemical washing. The washing chemicals of water, lime solution and EDTA solution were used single or combinational to sequential wash soil. Four crops of rice, soybean, corn and pumpkin were planted on treated soil in order to assess effects of chemical. The results indicated that water, lime solution and EDTA solution could extract heavy metals from soil, but their ability were different, with EDTA solution>water>lime solution. The four crops were able to germinate on treated soils, but all crops were all phytotoxic and died after germination on the soil washed by water or EDTA solution. The biomass of plants grown on the soils washed by lime solution or water +lime solution was higher than that

  6. Prepration of carbon black/oil soiled strips and the evaluation of its washing performance%炭黑油污布的制备及洗涤性能评价

    Institute of Scientific and Technical Information of China (English)

    王赢; 王平; 王强; 袁久刚; 陈黎明; 范雪荣

    2012-01-01

    As one of the standard soiled test strips, carbon black/oil soiled strips were widely used for measuring the washing performance of clothes washing machines. The preparation of novel carbon black/oil soiled strips based on aqueous systems were discussed. The effects of the dosage of Arabic gum powder, Peregal O, oil additive and emulsifying condition (rate and time) on the stability of carbon black/oil soiled solution were analyzed. The dyeing evenness and washing performance for the self-made carbon black/oil soiled strips were also evaluated. The results indicated that stable carbon black/oil soiled solution was obtained, when the dosage of Arabic gum powder and Peregal 0 were both 1.5%, using castor oil as additive with an emulsifying rate of 700 r/min for 50 min. Compared with the standard carbon black/oil soiled strips based on oil system (GB/T 4288-2008), the preparation method discussed in the paper was much easier, and the dyeing result and washing performance of achieved soiled strips were similar as the standard, which had potential application prospect.%炭黑油污布是检测洗衣机洗涤性能的常用标准污染布之一.探讨了水性体系中新型炭黑油污布的制备方法,分析了阿拉伯胶、平平加0、添加油剂及乳化条件(速度、时间)对污液稳定性的影响,评价了炭黑油污布的着色均匀性和洗涤性能.结果表明,以蓖麻油为添加油剂,阿拉伯胶、平平加0用量均为1.5%,经700 r/min乳化分散50 min,制得的污液稳定性较好.与油性体系中制备的标准炭黑油污布(GB/T 4288-2008)相比,炭黑油污布制备方法简单,污布色外观和洗涤性能与标准炭黑油污布相近,具有潜在的应用前景.

  7. U-ages in soils and groundwater evidencing wet periods 400-600 kyr ago in southeast Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Bonotto, D.M. [Departamento de Petrologia e Metalogenia, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil)]. E-mail: dbonotto@rc.unesp.br; Jimenez-Rueda, J.R. [Departamento de Petrologia e Metalogenia, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil)

    2007-07-15

    {sup 238}U and its radiogenic daughter {sup 234}U have been utilized for dating soil formation and groundwater residence time during the last 1.5 million years, in this case based on the U-dissolution/precipitation occurring during modifications of the oxidation-reduction conditions. In this paper, we report a 400-600 kyr proxy of wet periods from sediments occurring in a soil profile developed over rocks outcropping at the Parana sedimentary basin in Brazil, and from groundwater exploited of Guarani aquifer at the same basin. The approaches indicated successful use of the U-modeled ages for suggesting wet periods exceeding the past 116-210 kyr from previous studies.

  8. Evaluation of enhanced soil washing process and phytoremediation with maize oil, carboxymethyl-β-cyclodextrin, and vetiver grass for the recovery of organochlorine pesticides and heavy metals from a pesticide factory site.

    Science.gov (United States)

    Ye, Mao; Sun, Mingming; Liu, Zongtang; Ni, Ni; Chen, Yinwen; Gu, Chengang; Kengara, Fredrick Orori; Li, Huixin; Jiang, Xin

    2014-08-01

    An innovative ex situ soil washing technology was developed in this study to remediate organochlorine pesticides (OCPs) and heavy metals in a mixed contaminated site. Elevated temperature (60 °C) combined with ultrasonication (40 kHz, 20 min) at 50 mL L(-1) maize oil and 45 g L(-1) carboxylmethyl-β-cyclodextrin were effective in extracting pollutants from the soil. After two successive washing cycles, the removal efficiency rates for total OCPs, mirex, endosulfans, chlordanes, Cd, and Pb were approximately 94.7%, 87.2%, 98.5%, 92.3%, 91.6%, and 87.3%, respectively. Cultivation of vetiver grass and addition of nutrients for 3 months further degraded 34.7% of the residual total OCPs and partially restored the microbiological functions of the soil. This result was indicated by the significant increase in the number, biomass C, N, and functioning diversity of soil microorganisms (p < 0.05). After the treatment, the residual OCPs and heavy metals existed as very slowly desorbing fraction and residual fraction, as evaluated by Tenax extraction combined with a first-three-compartment model and sequential extraction. Moreover, the secondary environmental risk of residual pollutants in the remediated soil was at an acceptable level. The proposed combined cleanup strategy proved to be effective and environmentally friendly. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Correlation between geology and radon levels in groundwater, soil and indoor air in Bhilangana Valley, Garhwal Himalaya, India

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, V.M. [Wadia Inst. of Himalayan Geology, Dehra Dun (India); Ramola, R.C. [Dept. of Physics, H.N.B. Garhwal Univ. Campus, Tehri Garhwal (India)

    1997-11-01

    Radon concentrations were measured in soil, air and groundwater in Bhilangana Valley, Garhwal Himalaya, India by using an LR-115 plastic track detector and radon emanometer. Radon concentrations were found to vary from 1 KBq/m{sup 3} to 57 KBq/m{sup 3} in soil, 5 Bq/l to 887 Bq/l in water and 95 Bq/m{sup 3} to 208 Bq/m{sup 3} in air. The recorded values are quite high due to associated uranium mineralization in the area. Radon concentration was also found to depend on the tectonic structure and geology of the area. (orig.)

  10. Washing Phenanthrene and Pyrene Contaminated Soil Using Surfactant Solutions%表面活性剂对菲/芘模拟污染黄土的洗脱作用

    Institute of Scientific and Technical Information of China (English)

    刘婷; 钟金魁; 赵保卫; 冉婧媛; 石夏颖

    2013-01-01

    采用聚乙二醇辛基酚基醚(TX100)、聚氧乙烯失水山梨醇单油酸酯(TW80)、十二烷基苯磺酸钠(SDBS)和十二烷基硫酸钠(SDS)4种表面活性剂对菲、芘及其混合物模拟污染黄土进行洗脱实验,研究4种表面活性剂对菲、芘的洗脱作用.结果表明:随着表面活性剂浓度的提高,4种表面活性剂对菲、芘的去除作用均增强.对于单一的菲污染土壤,表面活性剂对菲去除率最大值的大小顺序为TW80>TX100>SDS>SDBS,最高可达92%.表面活性剂条件一定时,100 mg/L菲污染土壤的去除率高于1000 mg/L.对于单一的芘污染土壤,当表面活性剂浓度低于5000 mg/L时,TX100和TW80对芘的去除率高于SDS和SDBS,但浓度高于5000 mg/L时效果截然相反,最高可达66%.菲和芘混合污染土壤中,菲的去除率明显高于单一菲污染土壤,而芘的去除率却低于单一芘污染土壤.芘清洗1h后达到平衡,菲为4h.土水比越小表面活性剂对土壤中菲、芘的洗脱效果越好.%The batch equilibrium washing of phenanthrene and pyrene in the loess soil matrix by four surfactants, octylphenoxypolyethoxyethanol(TX100), ethoxylated anhydrosorbitol esters (TW80), sodium dode-cylbenzyl sulfonate (SDBS)and sodium dodecyl sulfate(SDS) was studied and compared. The influences of surfactant concentrations, shaking time and the ratio of soil to water were investigated. It was shown that the washing efficiency of phenanthrene and pyrene increased sharply with the increase of surfactant concentrations. The maximum washing efficiency of phenanthrene can be found following the order of TW80> TX100>SDS>SDBS, and the efficiency was up to 92 %. For pyrene, when surfactant concentrations were lower than 5000 mg/L, the efficiency by TW80 and TX100 were higher than that by SDS and SDBS. However, when surfactant concentrations were higher than 5000 mg/L, the result was opposite, and the washing efficiency was up to 66 %. Given the surfactant

  11. Coupling ANIMO and MT3DMS for 3D regional-scale modeling of nutrient transport in soil and groundwater

    Science.gov (United States)

    Janssen, G.; Del Val Alonso, L.; Groenendijk, P.; Griffioen, J.

    2012-12-01

    We developed an on-line coupling between the 1D/quasi-2D nutrient transport model ANIMO and the 3D groundwater transport model code MT3DMS. ANIMO is a detailed, process-oriented model code for the simulation of nitrate leaching to groundwater, N- and P-loads on surface waters and emissions of greenhouse gasses. It is the leading nutrient fate and transport code in the Netherlands where it is used primarily for the evaluation of fertilization related legislation. In addition, the code is applied frequently in international research projects. MT3DMS is probably the most commonly used groundwater solute transport package worldwide. The on-line model coupling ANIMO-MT3DMS combines the state-of-the-art descriptions of the biogeochemical cycles in ANIMO with the advantages of using a 3D approach for the transport through the saturated domain. These advantages include accounting for regional lateral transport, considering groundwater-surface water interactions more explicitly, and the possibility of using MODFLOW to obtain the flow fields. An additional merit of the on-line coupling concept is that it preserves feedbacks between the saturated and unsaturated zone. We tested ANIMO-MT3DMS by simulating nutrient transport for the period 1970-2007 in a Dutch agricultural polder catchment covering an area of 118 km2. The transient groundwater flow field had a temporal resolution of one day and was calculated with MODFLOW-MetaSWAP. The horizontal resolution of the model grid was 100x100m and consisted of 25 layers of varying thickness. To keep computation times manageable, we prepared MT3DMS for parallel computing, which in itself is a relevant development for a large community of groundwater transport modelers. For the parameterization of the soil, we applied a standard classification approach, representing the area by 60 units with unique combinations of soil type, land use and geohydrological setting. For the geochemical parameterization of the deeper subsurface, however, we

  12. 有机酸土柱淋洗法修复重金属污染土壤%Remediation of heavy metal-polluted soils using organic acid washing

    Institute of Scientific and Technical Information of China (English)

    梁金利; 蔡焕兴; 段雪梅; 戴玄吏; 余益军

    2012-01-01

    通过室内模拟实验,采用土柱淋洗方法,研究草酸、柠檬酸、乙酸和酒石酸溶液对某电镀厂附近土壤中重金属的去除效果。探讨了淋洗剂浓度、淋洗次数和淋洗时间等对淋洗效果的影响,研究草酸淋洗前后土壤中重金属形态的变化。结果表明,淋洗过程中铬的去除效果明显滞后于铜、锌和镍3种重金属离子。1 mol/L的草酸在土水比为1∶1,淋洗5h,淋洗4次的条件下可以达到最佳淋洗效果,Cu、Zn、Ni和Cr的去除率分别是99.6%、66.98%、88.7%和18.23%。%Laboratory simulation tests were conducted to examine the effects of different washing reagents(oxalic acid,citric acid,acetic acid and tartaric acid) in extracting the heavy metals from contaminated soils by galvanization factory.The effects of reagent concentration,reaction time,and washing time on the washing efficiency were investigated,and the form variation of test heavy metals was determined before and after oxalic acid washing.The experimental result shows that removal efficiency of chromium was lower than that of other three heavy metals.The highest washing efficiency was obtained under the optimal conditions,soil∶ liquid ratio was 1∶ 1,reaction time was 5 hours,and the soils were washed four times by oxalic acid solution.The removal rates of Cu,Zn,Ni,and Cr from test soils were 99.6%,66.98%,88.7% and 18.23%,respectively.

  13. Technical evaluation of the Intervention Values for Soil/sediment and Groundwater. Human and ecotoxicological risk assessment and derivation of risk limits for soil, aquatic sediment and groundwater

    NARCIS (Netherlands)

    Lijzen JPA; Baars AJ; Otte PF; Rikken M; Swartjes FA; Verbruggen EMJ; Wezel AP van; ECO

    2001-01-01

    Intervention Values are generic soil quality standards used to classify historically contaminated soils (i.e. before 1987) as seriously contaminated in the framework of the Dutch Soil Protection Act. In 1994 Intervention Values were published for 70 (groups of) compounds. These values, based on pote

  14. Substance-related environmental monitoring strategies regarding soil, groundwater and surface water - an overview.

    Science.gov (United States)

    Kördel, Werner; Garelick, Hemda; Gawlik, Bernd M; Kandile, Nadia G; Peijnenburg, Willie J G M; Rüdel, Heinz

    2013-05-01

    Substance-related monitoring is an essential tool within environmental risk assessment processes. The soundness of policy decisions including risk management measures is often directly related to the reliability of the environmental monitoring programs. In addition, monitoring programs are required for identifying new and less-investigated pollutants of concern in different environmental media. Scientifically sound and feasible monitoring concepts strongly depend on the aim of the study. The proper definition of questions to be answered is thus of pivotal importance. Decisions on sample handling, storage and the analysis of the samples are important steps for the elaboration of problem-oriented monitoring strategies. The same applies to the selection of the sampling sites as being representative for scenarios to be investigated. These steps may become critical to handle for larger international monitoring programs and thus trigger the quality of their results. This study based on the work of an IUPAC (International Union of Pure and Applied Chemistry) task group addresses different kinds and approaches of substance-related monitoring of different compartments of soil, groundwater and surface water, and discusses their advantages and limitations. Further important aspects are the monitoring across policies and the monitoring data management using information systems.

  15. SAFETY IMPROVES DRAMATICALLY IN FLUOR HANFORD SOIL AND GROUNDWATER REMEDIATION PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    GERBER MS

    2007-12-05

    This paper describes dramatic improvements in the safety record of the Soil and Groundwater Remediation Project (SGRP) at the Hanford Site in southeast Washington state over the past four years. During a period of enormous growth in project work and scope, contractor Fluor Hanford reduced injuries, accidents, and other safety-related incidents and enhanced a safety culture that earned the SGRP Star Status in the Department of Energy's (DOE's) Voluntary Protection Program (VPP) in 2007. This paper outlines the complex and multi-faceted work of Fluor Hanford's SGRP and details the steps taken by the project's Field Operations and Safety organizations to improve safety. Holding field safety meetings and walkdowns, broadening safety inspections, organizing employee safety councils, intensively flowing down safety requirements to subcontractors, and adopting other methods to achieve remarkable improvement in safety are discussed. The roles of management, labor and subcontractors are detailed. Finally, SGRP's safety improvements are discussed within the context of overall safety enhancements made by Fluor Hanford in the company's 11 years of managing nuclear waste cleanup at the Hanford Site.

  16. Radionuclide content of Las Vegas wash sediments

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, M.J.; Johnson, W.H.; Meyers, A.M. [University of Nevada-Las Vegas (United States). Dept. of Health Physics

    1997-12-31

    The Las Vegas Wash is an excavated waterway channel which drains all surface water and effluent discharge from sewage-treatment facilitates from the greater Las Vegas Metropolitan Area to Lake Mead. Fine and coarse sediment samples were collected at 100-m intervals and analyzed to determine the distribution of gamma-emitting radionuclides in the lower 5,500 m of the Las Vegas Wash. Results indicate depletion of long-lived fission products in upstream Wash sediments. However, trace levels of {sup 137}Cs measured in downstream sediments suggest the resuspension and transport of radioactive fallout within the Wash. Levels of {sup 40}K, {sup 232}Th, {sup 235}U, and {sup 238}U found in Wash sediments were consistent with levels typically found in southeast Nevada soils. (author).

  17. Effects of irrigated agroecosystems: 2. Quality of soil water and groundwater in the southern High Plains, Texas

    Science.gov (United States)

    Scanlon, B. R.; Gates, J. B.; Reedy, R. C.; Jackson, W. A.; Bordovsky, J. P.

    2010-09-01

    Trade-offs between water-resource depletion and salinization need to be understood when promoting water-conservative irrigation practices. This companion paper assesses impacts of groundwater-fed irrigation on soil water and groundwater quality using data from the southern High Plains (SHP). Unsaturated zone soil samples from 13 boreholes beneath irrigated agroecosystems were analyzed for water-extractable anions. Salt accumulation in soils varies with irrigation water quality, which ranges from low salinity in the north (median Cl: 21 mg/L) to higher salinity in the south (median Cl: 180 mg/L). Large Cl bulges under irrigated agroecosystems in the south are similar to those under natural ecosystems, but they accumulated over decades rather than millennia typical of natural ecosystems. Profile peak Cl concentrations (1200-6400 mg/L) correspond to irrigation efficiencies of 92-98% with respect to drainage and are attributed to deficit irrigation with minimal flushing. Perchlorate (ClO4) also accumulates under irrigated agroecosystems, primarily from irrigation water, and behaves similarly to Cl. Most NO3-N accumulation is below the root zone. Groundwater total dissolved solids (TDS) have increased by ≤960 mg/L and NO3-N by ≤9.4 mg/L since the early 1960s. Mobilization of salts that have accumulated under irrigated agroecosystems is projected to degrade groundwater much more in the future because of the essentially closed-basin status of the aquifer, with discharge occurring primarily through irrigation pumpage. TDS are projected to increase by an additional 2200 mg/L (median), ClO4 by 21 μg/L, and NO3-N by 52 mg/L. Water and salt balances should be considered in irrigation management in order to minimize salinization issues.

  18. Effects of Soil Moisture Content on Groundwater Electrical Resistivity Values in Irrigation Paddy Scheme, Tanjong Karang, Malaysia

    Directory of Open Access Journals (Sweden)

    Nurmala Sari

    2014-01-01

    Full Text Available Electrical Resistivity Tomography (ERT analyses have been conducted in Irrigation Paddy Scheme, Tanjong Karang, Malaysia as part of investigation on groundwater potential aquifer to provide an alternative water resource for paddy irrigation. Based on recent studies on groundwater resistivity in paddy field, irrigation system mentioned as soil moisture content was observed to affect the value of electrical resistivity and subsurface geological profile resulted from ERT analysis. The objective of this study was to proof any correlation between soil moisture content and electrical resistivity values and to determine at what level of soil moisture content which will be the best condition to conduct ERT survey. ERT analysis was conducted by using ABEM Terrameter SAS 4000 of Wenner-Schlumberger array with 5.0 meter and 10.0 meter for minimum and maximum electrode spacing. Visually, based on subsurface geological profile resulted from ERT analysis soil moisture content affected (changed electrical resistivity values. With all different treatments of soil moisture ranged from 16.96% to 27.50%, electrical resistivity values decreased in certain points and in certain depth along with the increase of soil moisture content. This was proofed by ANOVA and Duncan’s multiple range tests showing that Pr > F value was less than 0.0001. Further on Chi-square test showed that at soil moisture level of 22.54%, it was the best condition which gave more correct counts of electrical resistivity values compared to well lithology. This was assumed to be the best condition to conduct ERT survey.

  19. Preliminary development of a GIS-tool to assess threats to shallow groundwater quality from soil pollutants in Glasgow, UK (GRASP).

    Science.gov (United States)

    Dochartaigh, B. É. Ó.; Fordyce, F. M.; Ander, E. L.; Bonsor, H. C.

    2009-04-01

    The protection of groundwater and related surface water quality is a key aspect of the European Union Water Framework Directive and environmental legislation in many countries worldwide. Globally, the protection of urban groundwater resources and related ecosystem services is of growing concern as urbanisation increases. Although urban areas are often where groundwater resources are most in need of protection, there is frequently a lack of information about threats to groundwater quality. Most studies of soil and groundwater contamination, although detailed, are site-specific, and city-wide overviews are generally lacking. The British Geological Survey (BGS) is currently undertaking the Clyde Urban Super-Project (CUSP), delivering multi-disciplinary geoscience products for the Glasgow conurbation. Under this project, a GIS-based prioritisation tool known as GRASP (GRoundwater And Soil Pollutants) has been trialled to aid urban planning and sustainable development by providing a broad-scale assessment of threats to groundwater quality across the conurbation. GRASP identifies areas where shallow groundwater quality is at greatest threat from the leaching and downward movement of potentially harmful metals in the soil. Metal contamination is a known problem in many urban centres including Glasgow, which has a long industrial heritage and associated contamination legacy, notably with respect to Cr. GRASP is based primarily upon an existing British Standard - International Standards Organisation methodology to determine the leaching potential of metals from soils, which has been validated for 11 metals: Al, Fe, Cd, Co, Cr, Cu, Hg, Ni, Mn, Pb and Zn (BS-ISO 15175:2004). However, the GRASP tool is innovative as it combines assessments of soil leaching potential with soil metal content data to highlight threats to shallow groundwater quality. The input parameters required for GRASP (soil pH, clay, organic matter, sesquioxide and metal content) are based upon a systematic

  20. The groundwater-land-surface-atmosphere connection: soil moisture effects on the atmospheric boundary layer in fully-coupled simulations

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, R M; Chow, F K; Kollet, S J

    2007-02-02

    This study combines a variably-saturated groundwater flow model and a mesoscale atmospheric model to examine the effects of soil moisture heterogeneity on atmospheric boundary layer processes. This parallel, integrated model can represent spatial variations in land-surface forcing driven by three-dimensional (3D) atmospheric and subsurface components. The development of atmospheric flow is studied in a series of idealized test cases with different initial soil moisture distributions generated by an offline spin-up procedure or interpolated from a coarse-resolution dataset. These test cases are performed with both the fully-coupled model (which includes 3D groundwater flow and surface water routing) and the uncoupled atmospheric model. The effects of the different soil moisture initializations and lateral subsurface and surface water flow are seen in the differences in atmospheric evolution over a 36-hour period. The fully-coupled model maintains a realistic topographically-driven soil moisture distribution, while the uncoupled atmospheric model does not. Furthermore, the coupled model shows spatial and temporal correlations between surface and lower atmospheric variables and water table depth. These correlations are particularly strong during times when the land surface temperatures trigger shifts in wind behavior, such as during early morning surface heating.

  1. Arsenic contamination of the soil-wheat system irrigated with high arsenic groundwater in the Hetao Basin, Inner Mongolia, China.

    Science.gov (United States)

    Tong, Junting; Guo, Huaming; Wei, Chao

    2014-10-15

    As one of the most important crop in the world, wheat (Triticum aestivum L.) was irrigated with low As water and high As water. However, little is known about As cycling in the soil-wheat-water system. Two wheat fields (site G and site Y), irrigated with high dissolved As (178 μg L(-1)) groundwater and low dissolved As (8.2 μg L(-1)) surface water, respectively, were systematically sampled in the Hetao Basin, including irrigation water, soils and plants. The annual As (including dissolved As and suspended As) input per m(2) was estimated at 140 and 36.7 mg in site G and site Y, respectively. Topsoils of site G contained relatively higher As content (average 18.8 mg kg(-1)) than those of site Y (13.8 mg kg(-1)). Arsenic content of wheat grains in site G is systematically higher than in the site Y, which were positively correlated with non-specifically sorbed-As and amorphous Fe/Al oxide-bound As in topsoils. Arsenic-contaminated groundwater led to As accumulation in irrigated soils and the increase in As bioavailability, and subsequently resulted in the increase in As content of wheat grain. It suggested that less problematic water resources should be used for wheat irrigation in order to avoid As accumulation in the soil-plant system. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Arsenic species in broiler (Gallus gallus domesticus) litter, soils, maize (Zea mays L.), and groundwater from litter-amended fields.

    Science.gov (United States)

    D'Angelo, Elisa; Zeigler, Georgia; Beck, E Glenn; Grove, John; Sikora, Frank

    2012-11-01

    Manure and bedding material (litter) generated by the broiler industry (Gallus gallus domesticus) often contain high levels of arsenic (As) when organoarsenical roxarsone and p-arsanilic acid are included in feed to combat disease and improve weight gain of the birds. This study was conducted to determine As levels and species in litter from three major broiler producing companies, and As levels in soils, corn tissue (Zea mays L.), and groundwater in fields where litter was applied. Total As in litter from the three different integrators ranged between bioavailable As (extractable with Mehlich 3 solution and taken up by corn leaves). Arsenic concentrations in plant tissue and groundwater, however, were below the World Health Organization thresholds, which was attributed to strong sorption/precipitation of arsenate in Fe- and Al-rich soils. Ecological impacts of amending soils with As-laden litter depend on the As species in the litter, and chemical and physical properties of soil that strongly affect As mobility and bioavailability in the environment. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. The Method and Efifciency of Washing Crude Oil Using Sodium Humate in a Sandy Soil%腐植酸钠淋洗原油污染砂土方法与效果

    Institute of Scientific and Technical Information of China (English)

    张思鹏; 石海良; 蒋小川; 郭亮; 赵红艳

    2013-01-01

    The sandy soil samples that are moderately contaminated by ground crude oil are washed under different tem-perature, washing times and different reagents in this paper. The results show that the most effective washing order for removing the residual crude oil is reagents>washing times>temperature on the whole. All three reagents can wash crude oil out, but the removal efifciency is not considerably different. Alkaline solution, humic acid and self-made sodium hu-mate reach their maximum removal efifciency which are separately 24.89%, 22.28%and 21.83%.%  以原油污染的砂土为试验对象,研究市售腐植酸、自制腐植酸钠和碱水在不同洗涤次数和洗涤温度条件下,淋洗除去原油的效果。试验结果表明,整体上,各因素对砂土平均除油率的显著性依次为洗涤剂>洗涤次数>温度,其中洗涤剂种类和洗涤次数对清洗土壤的平均除油率影响都达到显著水平。从洗涤剂单一因素来看,3种洗涤剂对污染土样都有一定的洗涤效果,但除油率相差不大,自制的腐植酸钠、碱水和市售腐植酸的最大除油率分别是21.83%、24.89%、22.28%。

  4. 柠檬酸对铬污染不同质地土壤萃取与淋洗的研究%Study of Citric Acid on Extraction and Washing from Different Soil Polluted by Cr

    Institute of Scientific and Technical Information of China (English)

    姜晓琪; 李旭霖; 张娇; 吕姜宁; 昌晶; 崔德杰

    2012-01-01

    In order to explore extraction conditions and soil column washing about the citric acid to extract chromium (Cr) from different textures soils, the author took different concentrations, the liquid-solid ratios and the times and washing tests. The results showed that the analytical ability of the citric acid on 3 soils were sand soil>loam>clay. Sandy soil and loam needed big extraction conditions, clay needed smaller extraction conditions. Different concentrations effected extraction, when the concentration of citric acid was 0.05 mol/L, it was good to all the soils. The best liquid-solid ratio and time to soils were clay 1/14, 32 h; sandy soil 1/6, 16 h; loam 1/10, 28 h. The heavy metals contents of clay between 10 cm and 20 cm layer were bigger than other soil layers. The heavy metals contents of sand soil and loam between 30 cm and 40 cm layer were bigger than other soil layers. This research provided the technical support for removing chrome from soil.%为了探索柠檬酸对不同质地铬(Cr)污染土壤的萃取条件及淋洗效率,进行了不同浓度、固液比、时间的萃取和土柱淋洗试验.结果表明:柠檬酸对铬污染不同质地土壤修复效果为:砂土>壤土>粘土;砂土、壤土所需萃取条件较小,粘土较大.不同萃取条件对铬污染土壤萃取效果影响较大:柠檬酸浓度为0.05 mol/L时,3种土壤萃取效果较好.3种质地土壤最佳固液比和时间分别为:粘土1/14,32 h;砂土1/6,16h;壤土1/10,28 h.通过柠檬酸淋洗,粘土在10~20 cm土层发生再吸附,砂土与壤土在30~40 cm土层发生再吸附.本研究为铬污染土壤修复了提供技术支持.

  5. 液固比对土壤洗涤去除多环芳烃效果的影响%Influence of Operating Parameters on Surfactant-enhanced Washing to Remedy PAHs Contaminated Soil

    Institute of Scientific and Technical Information of China (English)

    吴威; 姜林; 陈家军; 彭胜

    2012-01-01

    液固比是影响土壤洗涤污染物去除率的重要因素.以Triton X-100和Tween-80为洗涤剂,采用洗涤去除率(R)、吸附损失率(Vs)和新定义的指标增溶百分比(SP)分析液固比对土壤洗涤去除目标多环芳烃效果的影响.结果表明,液固比对土壤洗涤去除多环芳烃效果影响显著.R随液固比增加呈非线性形式增大,液固比10∶1后R增长变缓.同一液固比时,洗涤去除率Triton X-100〉Tween-80.Vs随液固比增加显著减少,液固比10∶1后逐渐变缓.同一液固比时,吸附损失率Triton X-100%Liquid/solid ratio(L/S) is an important influencing factor on contaminant removal in soil washing.The impact of different liquid/solid ratio on washing performance with Triton X-100 and Tween-80 was studied respectively and evaluated through removal ratio(R),surfactant adsorption loss ratio(Vs) and solubilization percent(SP).The results presented that the performance of washing to remove PAHs in soil was significantly affected by liquid/solid ratio.PAH removal ratio was gradually increased with liquid/solid ratio increasing in the non-linear form,R presented nonlinear increasing until L/S=10∶1.Surfactant adsorption loss ratio was insignificantly decreased.At the same liquid/solid ratio,removal ratio of Triton X-100 is more than that of Tween-80.Vs presented drastic decreasing until L/S=10∶1,adsorption loss ratio of Triton X-100 is less than that of Tween-80.SP was decreased after maximum value is occurred at L/S=10∶1.Combining with R,Vsand SP,L/S=10∶1 should be an effective washing point,Triton X-100 should be a reasonable washing solution and SP is a more effective index to chose liquid/solid ratio.When Triton X-100 is as washing solution and L/S=10∶1,R,Vsand SP is 74.7%,23.47% and 48.99%,respectively.

  6. Geotechnology for groundwater and salinisation soil using geophysical prospecting; Butsuri tansa wo mochiita chikasui enrui dojo no tansa gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Chiba, A. [Sumitomo Metal Industries, Ltd., Osaka (Japan); Imaizumi, M.; Takeuchi, M. [National Research Institute of Agricultural Engineering, Tsukuba (Japan)

    1997-12-01

    This paper takes a general view of geophysical prospecting on groundwater and salinisation soil. It also explains the following examples of prospecting: an example of pursuing movement of saline water lump charged with a tracer by using a specific resistance monitor, as a monitoring survey being a representative example of `visualization of movement` expected as a direction to which physical prospecting should proceed in the future, an example of elucidating distribution of soil salts vertically and two-dimensionally by using the electromagnetic exploration method, and an example of surveying distribution of three-dimensional water permeation coefficients by utilizing geophysical prospecting systems, as an example of estimating property values from geophysical prospecting. Electrical prospecting has been used as an exploration method related to groundwater, whereas its method has been increasing the diversity, such as from vertical exploration to high-density horizontal exploration and tomography. Noticeable progress can also be seen in electromagnetic exploration and logging techniques. In addition, what is demanded in application of physical prospecting to groundwater field may include visualization of ground water flow, more precise estimation of hydraulic constants, and complement of their distribution. 22 refs., 21 figs., 3 tabs.

  7. Geothermal energy plants. Technologies and risk of soil and groundwater pollution; Jordvarmeanlaeg. Teknologier og risiko for jord- og grundvandsforurening

    Energy Technology Data Exchange (ETDEWEB)

    Villumsen, B. (COWI A/S, Kgs. Lyngby (Denmark))

    2008-07-01

    Ground source heat systems utilise the natural heat in the ground to heat houses and domestic hot water. The technology is energy-saving and can therefore contribute to the targets of reducing Denmark's CO{sub 2} emissions. All else being equal, a ground source heat system containing chemicals poses a potential contamination risk to soil and groundwater. Therefore a permit is required when installing a ground source heat system, and the general regulations for implementing the system etc. combined with the municipality's administrative procedures for the area must ensure sufficient protection of the groundwater. This project only deals with the heat exchanging system, which is the part of the ground source heat system which involves risk of soil and groundwater contamination. The aim of the project is to procure an overall updated knowledge base about the different types of ground source heat systems and the contamination risk associated with them. The project also reviews how disadvantages can be managed or minimized. (au)

  8. Chemistry of groundwater of Al-Ahsa Oasis eastern region Saudi Arabia and its predictive effects on soil properties.

    Science.gov (United States)

    Al-Zarah, Abdullah I

    2008-02-01

    Saudi Arabia is an arid and the largest country in the middle east with a total land area of 2.253 x 10(6) km2. Recent urban and rural expansion has shown manifold increases in water use in various sectors. Water resources are limited and non-renewable coupled with unpredicted scanty rainfall. In order to meet the rising water needs, evaluation of water quality is important for allocation to various uses. A total of 101 well water samples were collected from Al-Ahsa Oasis. Water samples were analyzed for total salt concentration, pH, Ca, Mg, Na, K, HCO3, Cl, SO4, NO3, F and B contents. Soil Salinity Development (SSD), adjusted sodium adsorption ratio (adj.SAR), adjusted sodium adsorption ratio (adj. R(Na)) and Exchangeable Sodium Percentage (ESP) were calculated. The EC of groundwater ranged between 1.23 and 5.05 dS m(-1). Sodium was the most abundant cation followed by Ca, Mg and K in descending order. Chloride was the most abundant anion followed by SO4 and HCO3 in groundwater of Al-Ahsa Oasis. A significant correlation was found between Na and Cl (R2 = 0.936). Thermodynamics calculation revealed that an appreciable amount of Ca and Mg is associated with Cl and SO4 ions. The SAR and ESP values are within the permissible limits according to Ayers and Westcot, 1985. The NO3 concentration is within safe limits for drinking purpose according to WHO (1998) standards. The Saturation Indices (SI) indicated that groundwater is under-saturated (negative SI) with respect to certain minerals (for example: calcite, dolomite, gypsum, anhydrite, halite, pyrite, fluorite and aragonite) and oversaturated (positive SI) with respect to some other minerals (For example: Goethite, Siderite and hematite). The negative saturation index (SI) reveals that most of minerals are in un-saturated state and will dissolve more Ca and Mg into the soil solution after irrigation. A good relationship exists between Cl and other ions (Na, Ca and Mg) as well as between SO4 and Ca and Mg ion of

  9. Groundwater recharge assessment at local and episodic scale in a soil mantled perched karst aquifer in southern Italy

    Science.gov (United States)

    Allocca, V.; De Vita, P.; Manna, F.; Nimmo, J. R.

    2015-10-01

    Groundwater recharge assessment of karst aquifers, at various spatial and temporal scales, is a major scientific topic of current importance, since these aquifers play an essential role for both socio-economic development and fluvial ecosystems. In this study, groundwater recharge was estimated at local and episodic scales in a representative perched karst aquifer in a region of southern Italy with a Mediterranean climate. The research utilized measurements of precipitation, air temperature, soil water content, and water-table depth, obtained in 2008 at the Acqua della Madonna test area (Terminio Mount karst aquifer, Campania region). At this location the aquifer is overlain by ash-fall pyroclastic soils. The Episodic Master Recession (EMR) method, an improved version of the Water Table Fluctuation (WTF) method, was applied to estimate the amount of recharge generated episodically by individual rainfall events. The method also quantifies the amount of precipitation generating each recharge episode, thus permitting calculation of the Recharge to the Precipitation Ratio (RPR) on a storm-by-storm basis. Depending on the seasonally varying air temperature, evapotranspiration, and precipitation patterns, calculated values of RPR varied between 35% and 97% among the individual episodes. A multiple linear correlation of the RPR with both the average intensity of recharging rainfall events and the antecedent soil water content was calculated. Given the relatively easy measurability of precipitation and soil water content, such an empirical model would have great hydrogeological and practical utility. It would facilitate short-term forecasting of recharge in karst aquifers of the Mediterranean region and other aquifers with similar hydrogeological characteristics. By establishing relationships between the RPR and climate-dependent variables such as average storm intensity, it would facilitate prediction of climate-change effects on groundwater recharge. The EMR methodology

  10. Influence of operating parameters on surfactant-enhanced washing to remedy PAHs contaminated soil%工艺参数对表面活性剂洗涤修复PAHs污染土壤的影响

    Institute of Scientific and Technical Information of China (English)

    吴威; 陈家军; 彭胜

    2012-01-01

    Surfactant-enhanced(TritonX-100 and Tween-80) soil washing technology was applied to investigate the influence of stirring speed,washing time,surfactant concentration,liquid/solid ratio,temperature,and on-and-off mode on the final removal of PAHs from contaminated soil.The optimum operating parameters were gained through a series of beaker experiments.The optimum washing time is 30 and 60 min respectively with TritonX-100 and Tween-80 as surfactant.As far other process parameters,the optimum value is the same with TritonX-100 or Tween-80.The optimum values of stirring speed,surfactant concentration,liquid/solid ratio,temperature,and on-and-off mode are 250 r/min,5 g/L,room temperature and continuous stirring,respectively.The overall residual ratio is less than 10 % under the conditions of above obtained optimum parameter values,which is basically in compliance with the remediation goals for five target PAHs.Therefore,it is very reasonable and feasible to apply surfactant-enhanced soil washing to remedy PAHs contaminated soil.%采用土壤洗涤(soil-washing)技术,分别用TritonX-100和Tween-80为强化洗涤剂研究了搅拌强度、洗涤时间、表面活性剂浓度、液固比、温度和间歇搅拌6个工艺参数对PAHs污染土壤洗涤效果的影响。通过一系列烧杯搅拌实验得到最佳洗涤工艺参数。TritonX-100和Tween-80的最佳洗涤时间分别是30 min和60 min,其他工艺参数最佳条件均相同。分别是搅拌强度为250 r/min,表面活性剂浓度为5 g/L,液固比为10∶1,温度为室温和连续搅拌。在此最佳工艺参数条件下,污染土中PAHs的残留率〈10%,基本上满足目标污染物的修复目标。应用表面活性剂强化洗涤技术修复PAHs污染土壤是合理和可行的。

  11. Remediation of a Lead Smelting Polluted Alkaline Soil with Washed Honeycomb Briquette Combustion Residue%不同洗涤蜂窝煤灰渣对铅冶炼污染石灰性土壤的修复研究

    Institute of Scientific and Technical Information of China (English)

    历琳; 邢维芹; 向国强; 王亚利; 吴洪敏; 王静; 李立平

    2012-01-01

    Honeycomb briquette combustion residue ( HBCR) is the solid combustion waste of honeycomb briquette, which is widely used for cooking in rural China. Investigations have confirmed that the HBCR can be used to immobilize lead(Pb) in soil spiked with soluble Pb. The purpose of this study was to evaluate the immobilization of Pb and Cd in alkaline lead smelting polluted soils with different HBCR. A polluted soil with 2337 mg·kg-1 Pb and 21.4 mg·kg-1 Cd was amended with un-washed HBCR, water-washed HBCR or dilute hydrochloric acid-washed HBCR at the rates of 1%, 2% or 4%, respectively. The soil was theri incubated for 60 days before being analyzed for DTPA-Cd, DT-PA-Pb, pH, electrical conductivity (EC) and Olsen-P. The results showed that, for the un-washed HBCR amended soil, increasing the rates of HBCR lead to the decreasing of Cd availability, and the DTPA-Cd contents was 13.1% lower than the control(P0.05). For the acid-washed HBCR amended soil, increasing the rates of HBCR lead to the increasing of Cd availability, and the effect was significant at the rate of 4%(P (P0.05), except that the un-washed HBCR increased the pH of the soil(P<0.05 ). The EC of soil amended with un-washed HBCR at the rates of 2% or 4%, and water-washed HBCR at rate of 4% were significantly higher than the control (P< 0.05). The results suggest that the water-washed HBCR can be used to immobilize Pb and Cd in lead-smelting polluted alkaline soil, adsorption of Pb2+ on the HBCR may be the primary mechanism of Pb immobilization by water-washed HBCR.%摘 要:为了探讨不同洗涤蜂窝煤灰渣对铅冶炼污染石灰性土壤中铅和镉的稳定效果,在铅冶炼污染石灰性土壤(Pb和Cd含量分别为2337、21.4 mg· kg-1)上分别施1%、2%和4%用量的原灰渣、水洗灰渣或酸洗灰渣,培养60 d后,测定土壤DTPA-Cd、DTPA-Pb、pH、电导率(EC)和Olsen-P.结果表明:对于原灰渣,土壤镉有效性随灰渣用量的增加而降低,在4%的用量下,土

  12. Inorganic carbon cycle in soil-rock-groundwater system in karst and fissured aquifers

    Directory of Open Access Journals (Sweden)

    Ajda Koceli

    2013-12-01

    Full Text Available The paper presents a systematic analysis of the isotopic composition of carbon (δ13CCaCO3 in carbonate rocks in central Slovenia, representing karst and fissured aquifers, and share of carbon contributions from carbonate dissolution and degradation of organic matter in aquifers, calculated from the mass balance equation. 59 samples of rocks (mainly dolomites from Upper Permian to Upper Triassic age were analyzed. Samples of carbonate rocks were pulverized and ground to fraction of 45 μm and for determination of δ13CCaCO3 analyzed with mass spectrometer for analyses of stable isotopes of light elements-IRMS. The same method was used for determination of isotopic composition of dissolved inorganic carbon (δ13CDIC in groundwater for 54 of 59 locations. Values of δ13CCaCO3 are in the range from -2.0 ‰ to +4.1 ‰, with an average δ13CCaCO3 value of +2.2 ‰. These values are typical for marine carbonates with δ13CCaCO3 around 0 ‰, although δ13CCaCO3 values differ between groups depending on the origin and age. Early diagenetic dolomites have relatively higher values of δ13CCaCO3 compared to other analyzed samples. The lowest values of δ13CCaCO3 were observed in Cordevolian and Bača dolomite, probably due to late diagenesis, during which meteoric water with lower isotopic carbon composition circulated in the process of sedimentation. Values of δ13CDIC range from -14.6 ‰ to -8.2 ‰. Higher δ13CDIC values (-8.2 ‰ indicate a low proportion of soil CO2 in the aquifer and rapid infiltration, while lower values (-14.6 ‰ indicate higher proportion of soil CO2 in the aquifer and slower infiltration. Calculated contributions of carbon from organic matter / dissolution of carbonates in the karstic and fissured aquifers s how a similar proportion (50 % : 50 %.

  13. 洗涤剂组合两步洗涤修复重金属污染土壤研究%Remediation of heavy metal contaminated soil by using two-step sequential washing with different reagents

    Institute of Scientific and Technical Information of China (English)

    尹雪; 陈家军; 吕策

    2014-01-01

    Washing performance of soil polluted by As, Cd, Cu, and Pb was studied to reveal the optimal parameters for remediation of heavy metal contaminated soil. Three reagents, namely citric acid, rhamnolipid, and oxalic acid, were selected and combined with EDTA, respectively. Compared with one-step washing, the two-step sequential washing with different reagents increased the removal efficiencies of As, Cd, Cu, and Pb by 8.45%~36.81%. The removal of As and Cu could reach 24.85% and 29.25%, respectively, when applying the two-step sequential washing with the combination of EDTA and oxalic acid, 47.83%of Cd and 30.59%of Pb in the soil could be eluted by washing with the combination of EDTA and rhamnolipid. After washing with the combination of EDTA and citric acid, the available contents of As, Cd, Cu and Pb in the soil decreased by 8.61%, 9.37%, 14.12%, and 25.16%, respectively. From practical perspective, the application of combining different reagents and adopting multi-step sequential washing require further process optimization, with special attention to the removal of both total metal amount and the available contents. The stability of heavy metal residues after remediation can thus be ensured, and subsequent impacts to the environment can be mitigated.%本文以某化工厂受As、Cd、Cu和Pb污染场地土壤为研究对象,将EDTA分别与柠檬酸、鼠李糖脂和草酸组合进行2轮搅拌洗涤修复,考察实验室条件下不同洗涤剂组合对重金属提取能力差异和形态分布的影响,研究多金属污染土壤的最佳洗涤方式.结果表明,与单轮洗涤相比,两轮洗涤处理明显提高了As、Cd、Cu和Pb的去除率,增幅范围在8.45%~36.81%.经过EDTA+草酸组合的洗涤,As和Cu的去除率分别可达24.04%和29.25%;EDTA+鼠李糖脂和鼠李糖脂+EDTA组合对Cd和Pb的去除效果显著,洗脱率分别为47.83%和30.59%.柠檬酸和EDTA组合能有效削减4种重金属有效态比例,使As、Cd、Cu

  14. Perennial filter strips reduce nitrate levels in soil and shallow groundwater after grassland-to-cropland conversion.

    Science.gov (United States)

    Zhou, Xiaobo; Helmers, Matthew J; Asbjornsen, Heidi; Kolka, Randy; Tomer, Mark D

    2010-01-01

    Many croplands planted to perennial grasses under the Conservation Reserve Program are being returned to crop production, and with potential consequences for water quality. The objective of this study was to quantify the impact of grassland-to-cropland conversion on nitrate-nitrogen (NO3-N) concentrations in soil and shallow groundwater and to assess the potential for perennial filter strips (PFS) to mitigate increases in NO3-N levels. The study, conducted at the Neal Smith National Wildlife Refuge (NSNWR) in central Iowa, consisted of a balanced incomplete block design with 12 watersheds and four watershed-scale treatments having different proportions and topographic positions of PFS planted in native prairie grasses: 100% rowcrop, 10% PFS (toeslope position), 10% PFS (distributed on toe and as contour strips), and 20 PFS (distributed on toe and as contour strips). All treatments were established in fall 2006 on watersheds that were under bromegrass (Bromus L.) cover for at least 10 yr. Nonperennial areas were maintained under a no-till 2-yr corn (Zea mays L.)--soybean [Glycine max. (L.) Merr.] rotation since spring 2007. Suction lysimeter and shallow groundwater wells located at upslope and toeslope positions were sampled monthly during the growing season to determine NO3-N concentration from 2005 to 2008. The results indicated significant increases in NO3-N concentration in soil and groundwater following grassland-to-cropland conversion. Nitrate-nitrogen levels in the vadose zone and groundwater under PFS were lower compared with 100% cropland, with the most significant differences occurring at the toeslope position. During the years following conversion, PFS mitigated increases in subsurface nitrate, but long-term monitoring is needed to observe and understand the full response to land-use conversion.

  15. Eco-efficient risk management of contaminated soil and groundwater (PIRRE); Pilaantuneen maaperaen ja pohjaveden riskienhallintaratkaisujen ekotehokkuus (PIRRE)

    Energy Technology Data Exchange (ETDEWEB)

    Sorvari, J.; Antikainen, R.; Gustafsson, J.; Haavisto, T.; Kivimaeki, A.L.; Kosola, M.L.; Ruuska, S. [Finnish Environmet Institute, Helsinki (Finland); Ollikainen, M.; Utriainen, E. [Helsinki Univ. (Finland); Hokkanen, P. [Tampere Univ. (Finland)

    2004-07-01

    'Eco-efficient risk management of contaminated soil and groundwater' (PIRRE) is an ongoing project, which aims for constructing a system to support decision making on risk management of contaminated sites. On the basis of our preliminary survey, the decisions are currently based on relatively few criteria. Methods to assess risks and costs are unestablished and documentation of the assessments often inadequate. The overall environmental impacts are seldom considered when selecting rehabilitation techniques. Excavation and disposal is still the most common method to manage contaminated soil. In many previous cases, cleaning of groundwater has been problematic and costly commonly due to insufficient data on the scope and manageability of contamination. These deficiencies along with the poor adoption of alternative remediation techniques, lack of economic instruments, and minimal exploitation of slightly contaminated soil have led to a situation where the management of contamination can seldom be considered as ecoefficient. The conceptual decision support system to be created within PIRRE will consist of decision criteria as well as recommended tools and data, which can be used to define their value qualitatively or quantitatively. (orig.)

  16. 不同洗涤蜂窝煤灰渣对污染土壤中铅的稳定作用研究%Immobilization of Lead in Soil with Washed Honeycomb Briquette Combustion Residue

    Institute of Scientific and Technical Information of China (English)

    李立平; 席欢; 邢维芹; 向国强; 张科; 胡昌乾

    2012-01-01

    Phosphate has been widely used as the most effective amendment for lead(Pb) in soil. Due to the limited phosphate rock resource, people are trying wastes or by-products as alternatives for phosphate. Honeycomb briquette combustion residue (HBCR) is a common solid waste in rural China. Our earlier work observed that HBCR could be used to immobilize Pb in soil, however, application of HBCR in soil resulted in elevated pH and electric conductivity( EC). In order to decrease its negative effect on the pH and EC of soil, HBCR was washed with water or dilute hydrochloric acid ( HC1) before being applied to a soil spiked with 1 000 mg · kg-1 Pb. The water- or dilute HCl-washing decreased pH( 1.94 and 3.70 pH unit, respectively, compared with the un-washed HBCR) and EC(0.785 and 0.890 mS·cm-1) of the HBCR greatly, and the availability and the total content of heavy metals slightly. Application of the water- or dilute HCl-washed HBCR resulted in higher availability of phosphorus in the soil. The concentrations of DTPA-extractable Pb in the soils amended with un-washed, water-washed and dilute HCl-washed HBCR decreased 67.2 mg·kg-1, 195 mg·kg-1 and 117 mg·kg-1, while these values were 102 mg·kg-1, 91.8 mg·kg-1 and 86.8 mg·kg-1, when amended with additional amendment of phosphate. The differences between the amended soils and the control were statistically significant at 0.05 level. Sequential extraction of the soil Pb indicated that the effect of different amendments on the Pb speciation was not robust. These results suggested that both water-and dilute HC1 -washings were effective in reducing the pH and EC of the HBCR, while water-washing was more effective in improving or maintaining the immobilization effect of Pb of HBCR.%蜂窝煤灰渣具有稳定污染土壤中铅的作用,但可增大土壤pH和电导率(EC).将蜂窝煤灰渣经过水洗和稀盐酸酸洗后加入铅污染土壤(1000mg.kg-1Pb),研究了不同处理灰渣对铅有效

  17. An investigation of groundwater organics, soil minerals, and activated carbon on the complexation, adsorption, and separation of technetium-99

    Energy Technology Data Exchange (ETDEWEB)

    Gu, B. [Oak Ridge National Lab., TN (United States). Environmental Sciences Div.; Dowlen, K.E. [Oak Ridge Associated Universities, TN (United States)

    1996-01-01

    This report summarizes studies on the interactions of technetium-99 (Tc) with different organic compounds and soil minerals under both oxidizing and reducing conditions. The report is divided into four parts and includes (1) effect of natural organic matter (NOM) on the complexation and solubility of Tc, (2) complexation between Tc and trichloroethylene (TCE) in aqueous solutions, (3) adsorption of Tc on soil samples from Paducah Gaseous Diffusion Plant (PGDP), and (4) adsorption and separation of Tc on activated carbon. Various experimental techniques were applied to characterize and identify Tc complexation with organic compounds and TCE, including liquid-liquid extraction, membrane filtration, size exclusion, and gel chromatography. Results indicate, within the experimental error, Tc (as pertechnetate, TcO{sub 4}) did not appear to form complexes with groundwater or natural organic matter under both atmospheric and reducing conditions. However, Tc can form complexes with certain organic compounds or specific functional groups such as salicylate. Tc did not appear to form complexes with TCE in aqueous solution.Both liquid-liquid extraction and high performance liquid chromatography (HPLC) gave no indication Tc was complexed with TCE. The correlations between Tc and TCE concentrations in monitoring wells at PGDP may be a coincidence because TCE was commonly used as a decontamination reagent. Once TCE and Tc entered the groundwater, they behaved similarly because both TcO{sub 4}{sup {minus}} and TCE are poorly adsorbed by soils. An effective remediation technique to remove TcO{sub 4}{sup {minus}} from PGDP contaminated groundwater is needed. One possibility is the use of an activated carbon adsorption technique developed in this study.

  18. Colonization and community structure of root-associated microorganisms of Sabina vulgaris with soil depth in a semiarid desert ecosystem with shallow groundwater.

    Science.gov (United States)

    Taniguchi, Takeshi; Usuki, Hiroyuki; Kikuchi, Junichi; Hirobe, Muneto; Miki, Naoko; Fukuda, Kenji; Zhang, Guosheng; Wang, Linhe; Yoshikawa, Ken; Yamanaka, Norikazu

    2012-08-01

    Arbuscular mycorrhizal fungi (AMF) have been observed in deep soil layers in arid lands. However, change in AMF community structure with soil depth and vertical distributions of the other root-associated microorganisms are unclear. Here, we examined colonization by AMF and dark septate fungi (DSF), as well as the community structure of AMF and endophytic fungi (EF) and endophytic bacteria (EB) in association with soil depth in a semiarid desert with shallow groundwater. Roots of Sabina vulgaris and soils were collected from surface to groundwater level at 20-cm intervals. Soil chemistry (water content, total N, and available P) and colonization of AMF and DSF were measured. Community structures of AMF, EF, and EB were examined by terminal restriction fragment length polymorphism analysis. AMF colonization decreased with soil depth, although it was mostly higher than 50%. Number of AMF phylotypes decreased with soil depth, but more than five phylotypes were observed at depths up to 100 cm. Number of AMF phylotypes had a significant and positive relationship with soil moisture level within 0-15% of soil water content. DSF colonization was high but limited to soil surface. Number of phylotypes of EF and EB were diverse even in deep soil layers, and the community composition was associated with the colonization and community composition of AMF. This study indicates that AMF species richness in roots decreases but is maintained in deep soil layers in semiarid regions, and change in AMF colonization and community structure associates with community structure of the other root-associated microorganisms.

  19. Assessment of groundwater, soil-gas, and soil contamination at the Vietnam Armor Training Facility, Fort Gordon, Georgia, 2009-2010

    Science.gov (United States)

    Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the groundwater, soil gas, and soil for contaminants at the Vietnam Armor Training Facility (VATF) at Fort Gordon, from October 2009 to September 2010. The assessment included the detection of organic compounds in the groundwater and soil gas, and inorganic compounds in the soil. In addition, organic contaminant assessment included organic compounds classified as explosives and chemical agents in selected areas. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Four passive samplers were deployed in groundwater wells at the VATF in Fort Gordon. Total petroleum hydrocarbons were detected above the method detection level at all four wells. The only other volatile organic compounds detected above their method detection level were undecane and pentadecane, which were detected in two of the four wells sampled. Soil-gas samplers were deployed at 72 locations in a grid pattern across the VATF. Total petroleum hydrocarbons were detected in 71 of the 72 samplers (one sampler was destroyed in the field and not analyzed) at levels above the method detection level, and the combined mass of benzene, toluene, ethylbenzene, and total xylene was detected above the detection level in 31 of the 71 samplers that were analyzed. Other volatile organic compounds detected above their respective method detection levels were naphthalene, 2-methyl-naphthalene, tridecane, 1,2,4-trimethylbenzene, and perchloroethene. Subsequent to the soil-gas survey, four areas determined to have elevated contaminant mass were selected and sampled for explosives and chemical agents. No detections of explosives or chemical agents above their

  20. Remediation of Chlordane and Mirex-contaminated Soil by Combined Soil Washing and Photodegradation Technique%土壤洗脱与光降解技术联合修复氯丹和灭蚁灵污染场地土壤的研究

    Institute of Scientific and Technical Information of China (English)

    徐君君; 郑冠宇; 徐峙晖; 占新华; 周立祥

    2015-01-01

    Organochlorine pesticides(OCPs)in soil have posed severe risks to the environment and human health. In this paper, the use of soil washing coupled with photodegradation for the remediation of soil contaminated with chlordane and mirex was investigated. In the soil washing experiment, sixteen solubilizing agents were tested for their washing efficiencies. It was found that Triton X-100, Tween 80 and HPCD had good washing efficiencies for chlordane and mirex. Since the chromophoric aryl group in Triton X-100 could absorb ultraviolet light, which might promote the photodegradation of chlordane and mirex, Triton X-100 was selected for optimizing parameters for washing chlordane and mirex from soil. The optimum parameters for Triton X-100 were 10 mmol·L-1 of concentration, 60 min of washing period, 1:10 of soil to washing agent ratio, and three successive washings. Under the optimum conditions, the removal efficiencies of chlordane and mirex from contaminated soil were 98.7%and 45.3%, respectively. The eluate obtained was then subjected to photodegradation. Under the irradiation of Hg lamp, chlordane was completely degraded within only 3 h and nearly 100%of mirex was degraded in only 1 h. The present results suggest that soil washing combined with photodegradation could be a useful option for the remediation of soil contaminated with chlordane and mirex.%探讨土壤洗脱与光降解技术联合修复有机污染土壤的可行性,对于有效控制土壤中的有机污染物有重要意义。针对氯丹和灭蚁灵生产企业场地污染土壤,选取16种洗脱剂对其中的氯丹和灭蚁灵进行增效洗脱,优化了Triton X-100洗脱污染土壤的工艺条件,并进一步研究了采用光降解技术降解洗脱液中氯丹和灭蚁灵的可行性。结果表明,Triton X-100、Tween 80和HPCD对复合污染土壤中氯丹和灭蚁灵均有较好的洗脱效果,由于Triton X-100中的发色芳基可吸收紫外光,促进污

  1. Health risk estimates for groundwater and soil contamination in the Slovak Republic: a convenient tool for identification and mapping of risk areas.

    Science.gov (United States)

    Fajčíková, K; Cvečková, V; Stewart, A; Rapant, S

    2014-10-01

    We undertook a quantitative estimation of health risks to residents living in the Slovak Republic and exposed to contaminated groundwater (ingestion by adult population) and/or soils (ingestion by adult and child population). Potential risk areas were mapped to give a visual presentation at basic administrative units of the country (municipalities, districts, regions) for easy discussion with policy and decision-makers. The health risk estimates were calculated by US EPA methods, applying threshold values for chronic risk and non-threshold values for cancer risk. The potential health risk was evaluated for As, Ba, Cd, Cu, F, Hg, Mn, NO3 (-), Pb, Sb, Se and Zn for groundwater and As, B, Ba, Be, Cd, Cu, F, Hg, Mn, Mo, Ni, Pb, Sb, Se and Zn for soils. An increased health risk was identified mainly in historical mining areas highly contaminated by geogenic-anthropogenic sources (ore deposit occurrence, mining, metallurgy). Arsenic and antimony were the most significant elements in relation to health risks from groundwater and soil contamination in the Slovak Republic contributing a significant part of total chronic risk levels. Health risk estimation for soil contamination has highlighted the significance of exposure through soil ingestion in children. Increased cancer risks from groundwater and soil contamination by arsenic were noted in several municipalities and districts throughout the country in areas with significantly high arsenic levels in the environment. This approach to health risk estimations and visualization represents a fast, clear and convenient tool for delineation of risk areas at national and local levels.

  2. Pollution Characteristics of Heavy Metals in Agricultural Soils near an E-waste Acid Washing Treatment Site%电子废物酸浴处置区附近农田土壤重金属污染特征

    Institute of Scientific and Technical Information of China (English)

    郭莹莹; 黄泽春; 王琪; 黄启飞; 张增强

    2011-01-01

    分析了我国南方某典型电子废物酸浴提取贵重金属场地周围农田土壤剖面 pH,重金属含量以及重金属的形态分布特征.结果表明:酸浴提取贵重金属场地周围土壤酸化现象明显,随着距酸浴源距离的增大以及土层深度的增加,酸化程度均减弱;底层土壤酸污染范围较小,仅限于距离污染场地很近的范围内.调查区土壤 Cu和Ni 2 种重金属的污染较为严重,Cd和Pb 污染相对较轻.与酸污染相似,土壤中 Cu和Ni 的污染随着距酸浴源距离的增大以及土层深度的增加而减弱,表层最高分别超过对照点 6 倍和 4 倍.酸浴污染土壤中重金属活性态比例普遍较高,活性态比例随距酸浴场地距离和土层深度的变化趋势与土壤酸污染相似.%The distribution characteristics of pH and the contents and species of heavy metals were investigated in agricultural soil profiles near a typical e-waste acid washing treatment site in southern China. The results showed that obvious acidification was found in the soil profiles around the e-waste acid washing site. Soil acidification decreased along with increased distance away from the site and increased depth of the soil profile. Serious acidification was constrained to soil close to the site. Cu, Ni, Cd and Pb contamination were found in this area. Among them, the contamination of Cu and Ni were relatively serious. The trend of soil acidification was that the contamination of Cu and Ni also decreased with increased distance from the site and increased depth of the soil profile. The concentrations of Cu and Ni in the surface soils were over six and four times higher, respectively, than those in the background soils.Relatively high ratios of active forms of heavy metals were found in the soils contaminated by e-waste acid washing treatment. The distribution of the percentage of active forms in the soil was similar to the trends of soil acidification.

  3. Evaluation of Phytoremediation for Management of Chlorinated Solvents in Soil and Groundwater

    Science.gov (United States)

    This document is intended to aid regulators, site owners, consultants, neighbors, and other stakeholders in understanding the proper application of planted systems to remediate groundwater contaminated with halogenated solvents.

  4. RELATIONSHIP AMONG EVAPORATION FLUX OF GROUNDWATER, DEPTH OF WATER TABLE AND NEGATIVE PRESSURE HEAD IN BARE SOIL

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Evaporation of ground water is a part of moisture circulation in the field.And it is a main natural form in which water transmits from the ground water to the soil water and atmosphere water.According to the simulated experiments, we study the relationship among the evaporation, depth of groundwater table and negative pressure.By theoretical analysis of the experimental results, the main conclusions are drawn as follows.There are two abrupt points in every Q-H curve.The locations of the abrupt points are separately in step with the height of top of the capillary fringe and the height of maximal capillary rise in the soil section.When the depth of ground water table H is small, the evaporation flux of ground water is large.While the depth of water table exceeds the maximal capillary rise of media in vadose zone, the capillary rise breaks up and evaporation flux of groundwater is small.The water content ratio in ground surface tends to be zero and the surface of soil tends to be drought.These conclusions show that the maximal capillary rise of media in vadose zone is an important value in regulating rational depth of ground water to reduce the evaporation of ground water and to increase effective quantity of water resources.In the meantime, these conclusions are of important theoretical and practical significance to reduce the evaporation of ground water, to prevent and cure the salinization of soil, and to make full use of and protect water resources in the northern plains in China.

  5. Irrigated greywater in an urban sub-division as a potential source of metals to soil, groundwater and surface water.

    Science.gov (United States)

    Turner, Ryan D R; Warne, Michael St J; Dawes, Les A; Vardy, Suzanne; Will, Geoffrey D

    2016-12-01

    Increased water demands in dry countries such as Australia, have led to increased adoption of various water reuse practices. Irrigation of greywater (all water discharged from the bathrooms, laundry and kitchen apart from toilet waste) is seen as a potential means of easing water demands; however, there is limited knowledge of how greywater irrigation impacts terrestrial and aquatic environments. This study compared four greywater irrigated residential lots to adjacent non-irrigated lots that acted as controls. Accumulation and potential impacts of metals in soil, groundwater and surface water, as a result of greywater irrigation, were assessed by comparing measured concentrations to national and international guidelines. Greywater increased concentrations of some metals in irrigated soil and resulted in As, B, Cr and Cu exceeding guidelines after only four years of irrigation. Movement of metals from the irrigation areas resulted in metal concentrations in groundwater (Al, As, Cr, Cu, Fe, Mn, Ni and Zn) and surface water (Cu, Fe and Zn) exceeding environmental quality guidelines again within four years. These results are unlikely to be universally applicable but indicate the need to consider metals in greywater in order to minimize potential adverse environmental effects from greywater irrigation.

  6. Identifying groundwater recharge connections in the Moscow (USA) sub-basin using isotopic tracers and a soil moisture routing model

    Science.gov (United States)

    Candel, Jasper; Brooks, Erin; Sánchez-Murillo, Ricardo; Grader, George; Dijksma, Roel

    2016-06-01

    Globally, aquifers are suffering from large abstractions resulting in groundwater level declines. These declines can be caused by excessive abstraction for drinking water, irrigation purposes or industrial use. Basaltic aquifers also face these conflicts. A large flood basalt area (1.1 × 105 km2) can be found in the Northwest of the USA. This Columbia River Basalt Group (CRBG) consists of a thick series of basalt flows of Miocene age. The two major hydrogeological units (Wanapum and Grand Ronde formations) are widely used for water abstraction. The mean decline over recent decades has been 0.6 m year-1. At present day, abstraction wells are drying up, and base flow of rivers is reduced. At the eastern part of CRBG, the Moscow sub-basin on the Idaho/Washington State border can be found. Although a thick poorly permeable clay layer exists on top of the basalt aquifer, groundwater level dynamics suggest that groundwater recharge occurs at certain locations. A set of wells and springs has been monitored bi-weekly for 9 months for δ18O and δ2H. Large isotopic fluctuations and d-excess values close to the meteoric water line in some wells are indicating that recharge occurs at the granite/basalt interface through lateral flow paths in and below the clay. A soil moisture routing (SMR) model showed that most recharge occurs on the granitic mountains. The basaltic aquifer receives recharge from these sedimentary zones around the granite/basalt interface. The identification of these types of areas is of major importance for future managed-aquifer recharge solutions to solve problems of groundwater depletion.

  7. Identifying groundwater recharge connections in the Moscow (USA) sub-basin using isotopic tracers and a soil moisture routing model

    Science.gov (United States)

    Candel, Jasper; Brooks, Erin; Sánchez-Murillo, Ricardo; Grader, George; Dijksma, Roel

    2016-11-01

    Globally, aquifers are suffering from large abstractions resulting in groundwater level declines. These declines can be caused by excessive abstraction for drinking water, irrigation purposes or industrial use. Basaltic aquifers also face these conflicts. A large flood basalt area (1.1 × 105 km2) can be found in the Northwest of the USA. This Columbia River Basalt Group (CRBG) consists of a thick series of basalt flows of Miocene age. The two major hydrogeological units (Wanapum and Grand Ronde formations) are widely used for water abstraction. The mean decline over recent decades has been 0.6 m year-1. At present day, abstraction wells are drying up, and base flow of rivers is reduced. At the eastern part of CRBG, the Moscow sub-basin on the Idaho/Washington State border can be found. Although a thick poorly permeable clay layer exists on top of the basalt aquifer, groundwater level dynamics suggest that groundwater recharge occurs at certain locations. A set of wells and springs has been monitored bi-weekly for 9 months for δ18O and δ2H. Large isotopic fluctuations and d-excess values close to the meteoric water line in some wells are indicating that recharge occurs at the granite/basalt interface through lateral flow paths in and below the clay. A soil moisture routing (SMR) model showed that most recharge occurs on the granitic mountains. The basaltic aquifer receives recharge from these sedimentary zones around the granite/basalt interface. The identification of these types of areas is of major importance for future managed-aquifer recharge solutions to solve problems of groundwater depletion.

  8. Long-term (1930-2010) trends in groundwater levels in Texas: influences of soils, landcover and water use.

    Science.gov (United States)

    Chaudhuri, Sriroop; Ale, Srinivasulu

    2014-08-15

    Rapid groundwater depletion has raised grave concerns about sustainable development in many parts of Texas, as well as in other parts of the world. Previous hydrologic investigations on groundwater levels in Texas were conducted mostly on aquifer-specific basis, and hence lacked state-wide panoramic view. The aim of this study was to present a qualitative overview of long-term (1930-2010) trends in groundwater levels in Texas and identify spatial patterns by applying different statistical (boxplots, correlation-regression, hierarchical cluster analysis) and geospatial techniques (Moran's I, Local Indicators of Spatial Association) on 136,930 groundwater level observations from Texas Water Development Board's database. State-wide decadal median water-levels declined from about 14 m from land surface in the 1930s to about 36 m in the 2000s. Number of counties with deeper median water-levels (water-level depth>100 m) increased from 2 to 13 between 1930s and 2000s, accompanied by a decrease in number of counties having shallower median water-levels (water-level depthlandcover, geology and soil properties distinguished Texas Panhandle from GMA 8. Irrigated agriculture is the major cause of depletion in the Texas Panhandle as compared to increasing urbanization in GMA 8. Overall our study indicated that use of robust spatial and statistical methods can reveal important details about the trends in water-level changes and shed lights on the associated factors. Due to very generic nature, techniques used in this study can also be applied to other areas with similar eco-hydrologic issues to identify regions that warrant future management actions.

  9. Application of Surfactants in Washing of Diesel-oil-contaminated Soil%表面活性剂在柴油污染土壤洗涤中的应用

    Institute of Scientific and Technical Information of China (English)

    吕璠璠; 陈泉源

    2015-01-01

    采用表面活性剂十二烷基硫酸钠( SDS)、十二烷基苯磺酸钠( LAS)、辛基酚聚氧乙烯醚( TX-100)和聚氧乙烯失水山梨醇单油酸酯( Tween-80)洗涤柴油污染土壤,研究了表面活性剂浓度、pH值、助剂硅酸钠浓度、液固比、洗涤时间、搅拌强度和温度对污染土壤洗涤效果的影响。研究结果表明,SDS、LAS、TX-100和Tween-80最佳浓度分别为3,4,0.8和0.06 g/L;助剂硅酸钠浓度对阴离子表面活性剂( SDS、LAS)洗涤基本没有影响,但较高的硅酸钠浓度(大于5 g/L)对非离子表面活性剂( TX-100、Tween-80)洗涤有强化作用;在pH>6、搅拌强度200 r/min、液固比20∶1、常温搅拌30 min条件下,LAS的洗涤效果显著,柴油去除率可达90%以上。%Surfactants including SDS, LAS, TX-100 and Tween-80 were used as detergents for washing diesel⁃oil⁃contaminated soil. The influences of surfactant concentration, pH value, sodium silicate concentration, liquid/solid ratio, washing time, stirring speed and temperature on the washing effect were studied. It was demonstrated that the optimum surfactant concentration was 3 g/L, 4 g/L, 0.8 g/L and 0.06 g/L for SDS, LAS, TX-100 and Tween-80, respectively. Sodium silicate exhibited no effect on the washing performance of anion surfactants ( SDS or LAS ) , but relatively higher concentration of sodium silicate (>5 g/L) enhanced the washing effects of non⁃ionic surfactants ( TX-100 or Tween-80) on diesel⁃oil⁃contaminated soil. Under the conditions of pH>6, stirring speed at 200 r/min, liquid/solid ratio as 20∶1, washing at room temperature for 30 min showed an evident washing efficiency of LAS, resulting in removing rate of diesel oil up to 90%.

  10. Extreme environments in the critical zone: Linking acidification hazard of acid sulfate soils in mound spring discharge zones to groundwater evolution and mantle degassing.

    Science.gov (United States)

    Shand, Paul; Gotch, Travis; Love, Andrew; Raven, Mark; Priestley, Stacey; Grocke, Sonia

    2016-10-15

    A decrease in flow from the iconic travertine mound springs of the Great Artesian Basin in South Australia has led to the oxidation of hypersulfidic soils and extreme soil acidification, impacting their unique groundwater dependent ecosystems. The build-up of pyrite in these systems occurred over millennia by the discharge of deep artesian sulfate-containing groundwaters through organic-rich subaqueous soils. Rare iron and aluminium hydroxysulfate minerals form thick efflorescences due to high evaporation rates in this arid zone environment, and the oxidised soils pose a significant risk to local aquatic and terrestrial ecosystems. The distribution of extreme acidification hazard is controlled by regional variations in the hydrochemistry of groundwater. Geochemical processes fractionate acidity and alkalinity into separate parts of the discharge zone allowing potentially extreme environments to form locally. Differences in groundwater chemistry in the aquifer along flow pathways towards the spring discharge zone are related to a range of processes including mineral dissolution and redox reactions, which in turn are strongly influenced by degassing of the mantle along deep crustal fractures. There is thus a connection between shallow critical zone ecosystems and deep crustal/mantle processes which ultimately control the formation of hypersulfidic soils and the potential for extreme geochemical environments.

  11. Influences of soil hydraulic and mechanical parameters on land subsidence and ground fissures caused by groundwater exploitation

    Institute of Scientific and Technical Information of China (English)

    陈兴贤; 骆祖江; 周世玲

    2014-01-01

    In order to study the influences of hydraulic and mechanical parameters on land subsidence and ground fissure caused by groundwater exploitation, based on the Biot’s consolidation theory and combined with the nonlinear rheological theory of soil, the constitutive relation in Biot’s consolidation theory is extended to include the viscoelastic plasticity, and the dynamic relationship among the porosity, the hydraulic conductivity, the parameters of soil deformation and effective stress is also considered, a three-dimensional full coupling mathematical model is established and applied to the study of land subsidence and ground fissures of Cangzhou in Hebei Province, through the analysis of parameter sensitivity, the influences of soil hydraulic and mechanical parame-ters on land subsidence and ground fissure are revealed. It is shown that the elastic modulus E , the Poisson ratio, the specific yield m and the soil cohesion c have a great influence on the land subsidence and the ground fissures. In addition, the vertical hydraulic conductivity zk and the horizontal hydraulic conductivity ks also have a great influence on the land subsidence and the ground fissures.

  12. Natural and Enhanced Attenuation of Soil and Groundwater at the Monument Valley, Arizona, DOE Legacy Waste Site—10281

    Energy Technology Data Exchange (ETDEWEB)

    Waugh, W.J. [S.M. Stoller Corporation, Grand Junction, CO; Miller, D.E. [S.M. Stoller Corporation, Grand Junction, CO; Morris, S.A. [S.M. Stoller Corporation, Grand Junction, CO; Sheader, L.R. [S.M. Stoller Corporation, Grand Junction, CO; Glenn, E.P. [University of Arizona, Tucson, AZ; Moore, D. [University of Arizona, Tucson, AZ; Carroll, K.C. [University of Arizona, Tucson, AZ; Benally, L. [Navajo Nation, Window Rock, AZ; Roanhorse, M. [Navajo Nation, Window Rock, AZ; Bush, R.P. [U.S. Department of Energy, Grand Junction, CO; none,

    2010-03-07

    The U.S. Department of Energy (DOE), the Navajo Nation, and the University of Arizona are exploring natural and enhanced attenuation remedies for groundwater contamination at a former uranium-ore processing site near Monument Valley, Arizona. DOE removed radioactive tailings from the Monument Valley site in 1994. Nitrate and ammonium, waste products of the milling process, remain in an alluvial groundwater plume spreading from the soil source where tailings were removed. Planting and irrigating two native shrubs, fourwing saltbush and black greasewood, markedly reduced both nitrate and ammonium in the source area over an 8-year period. Total nitrogen dropped from 350 mg/kg in 2000 to less than 200 mg/kg in 2008. Most of the reduction is attributable to irrigation-enhanced microbial denitrification rather than plant uptake. However, soil moisture and percolation flux monitoring show that the plantings control the soil water balance in the source area, preventing additional leaching of nitrogen compounds. Enhanced denitrification and phytoremediation also look promising for plume remediation. Microcosm experiments, nitrogen isotopic fractionation analysis, and solute transport modeling results suggest that (1) up to 70 percent of nitrate in the plume has been lost through natural denitrification since the mill was closed in 1968, and (2) injection of ethanol may accelerate microbial denitrification in plume hot spots. A field-scale ethanol injection pilot study is underway. Landscape-scale remote sensing methods developed for the project suggest that transpiration from restored native phreatophyte populations rooted in the aquifer could limit further expansion of the plume. An evaluation of landfarm phytoremediation, the irrigation of native shrub plantings with high nitrate water pumped from the alluvial aquifer, is also underway.

  13. Linking soil moisture balance and source-responsive models to estimate diffuse and preferential components of groundwater recharge

    Science.gov (United States)

    Cuthbert, M.O.; Mackay, R.; Nimmo, J.R.

    2012-01-01

    Results are presented of a detailed study into the vadose zone and shallow water table hydrodynamics of a field site in Shropshire, UK. A conceptual model is developed and tested using a range of numerical models, including a modified soil moisture balance model (SMBM) for estimating groundwater recharge in the presence of both diffuse and preferential flow components. Tensiometry reveals that the loamy sand topsoil wets up via macropore flow and subsequent redistribution of moisture into the soil matrix. Recharge does not occur until near-positive pressures are achieved at the top of the sandy glaciofluvial outwash material that underlies the topsoil, about 1 m above the water table. Once this occurs, very rapid water table rises follow. This threshold behaviour is attributed to the vertical discontinuity in the macropore system due to seasonal ploughing of the topsoil, and a lower permeability plough/iron pan restricting matrix flow between the topsoil and the lower outwash deposits. Although the wetting process in the topsoil is complex, a SMBM is shown to be effective in predicting the initiation of preferential flow from the base of the topsoil into the lower outwash horizon. The rapidity of the response at the water table and a water table rise during the summer period while flow gradients in the unsaturated profile were upward suggest that preferential flow is also occurring within the outwash deposits below the topsoil. A variation of the source-responsive model proposed by Nimmo (2010) is shown to reproduce the observed water table dynamics well in the lower outwash horizon when linked to a SMBM that quantifies the potential recharge from the topsoil. The results reveal new insights into preferential flow processes in cultivated soils and provide a useful and practical approach to accounting for preferential flow in studies of groundwater recharge estimation.

  14. Linking soil moisture balance and source-responsive models to estimate diffuse and preferential components of groundwater recharge

    Directory of Open Access Journals (Sweden)

    M. O. Cuthbert

    2013-03-01

    Full Text Available Results are presented of a detailed study into the vadose zone and shallow water table hydrodynamics of a field site in Shropshire, UK. A conceptual model is presented and tested using a range of numerical models, including a modified soil moisture balance model (SMBM for estimating groundwater recharge in the presence of both diffuse and preferential flow components. Tensiometry reveals that the loamy sand topsoil wets up via preferential flow and subsequent redistribution of moisture into the soil matrix. Recharge does not occur until near-positive pressures are achieved at the top of the sandy glaciofluvial outwash material that underlies the topsoil, about 1 m above the water table. Once this occurs, very rapid water table rises follow. This threshold behaviour is attributed to the vertical discontinuity in preferential flow pathways due to seasonal ploughing of the topsoil and to a lower permeability plough/iron pan restricting matrix flow between the topsoil and the lower outwash deposits. Although the wetting process in the topsoil is complex, a SMBM is shown to be effective in predicting the initiation of preferential flow from the base of the topsoil into the lower outwash horizon. The rapidity of the response at the water table and a water table rise during the summer period while flow gradients in the unsaturated profile were upward suggest that preferential flow is also occurring within the outwash deposits below the topsoil. A variation of the source-responsive model proposed by Nimmo (2010 is shown to reproduce the observed water table dynamics well in the lower outwash horizon when linked to a SMBM that quantifies the potential recharge from the topsoil. The results reveal new insights into preferential flow processes in cultivated soils and provide a useful and practical approach to accounting for preferential flow in studies of groundwater recharge estimation.

  15. Radionuclide content of Las Vegas wash sediments

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, M.J.; Meyers, A.M.; Johnson, W.H. [Univ. of Nevada, Las Vegas, NV (United States)

    1996-06-01

    The Las Vegas Wash is an excavated waterway channel which drains all surface water and effluent discharge from sewage-treatment facilities from the greater Las Vegas Metropolitan Area to Lake Mead. Runoff and erosion processes are expected to transport man-made radioactivity that was deposited over the past several decades in the Las Vegas Valley. Additionally, radionuclides disposed of via the city`s sanitary system are expected to accumulate in the Wash sediments. Fine and coarse sediment samples were collected at 100 m intervals and analyzed to determine the distribution of alpha- and gamma-emitting radionuclides in the lower 5,500 in of the Las Vegas Wash. Results indicate little accumulation of long-lived fission products in upstream Wash sediments. However, trace amounts of fission products measured in downstream sediments suggest the resuspension and transport of radioactive particulate matter within the Wash. Levels of naturally-occurring radionuclides found in Wash sediments were found to be consistent with levels typically found in southeast Nevada soils.

  16. Accumulation of Metals in Soils, Groundwater and Edible Parts of Crops Grown Under Long-Term Irrigation with Sewage Mixed Industrial Effluents.

    Science.gov (United States)

    Yadav, R K; Minhas, P S; Lal, Khajanchi; Chaturvedi, R K; Yadav, Gajender; Verma, T P

    2015-08-01

    Farmers in developing countries irrigate crops using raw urban and industrial effluents with consequent risks from metal contamination. Therefore, soils, crops and groundwater from an effluent irrigation use site were assessed for Cd, Cr, Ni and Pb. Total and available contents of metals in soil followed the order Pb>Ni>Cr>Cd. Crops accumulated more Pb, followed by Cd, Ni and Cr. Pb exceeded the permissible limit with wastewater irrigation only, but Cd exceeded the limit even with combined irrigations of wastewater and groundwater. Among crops, sugar beet assimilated highest Cd (3.14 μg g(-1)) and Pb (6.42 μg g(-1)) concentrations. Legumes accumulated more metals than cereals. Long-term use of wastewater and its conjunctive use with groundwater led to toxic accumulations of Cd, Pb, Ni and Cr. Cd with higher availability and mobility indices and lower toxicity limit, posed the maximum risk of food-chain contamination.

  17. Preliminary Soil and Groundwater Characterization Study at the CFAD Dundurn Explosives Facility (Saskatchewan)

    Science.gov (United States)

    1996-10-01

    circulation and transformation in groundwater we propose also to install two succion lysimeters in the vadose zone in the main burning area. The...aquifer classification should also be better known. More wells and a few succion Iysimeters must be installed to better understand the behavior of

  18. Sorption, degradation and mobility of microcystins in Chinese agriculture soils: risk assessment for groundwater protection

    Energy Technology Data Exchange (ETDEWEB)

    Chen Wei [State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Donghu Nanlu No 7, Wuhan 430072 (China); Graduate School of Chinese Academy of Sciences, Beijing 100049 (China); Song Lirong [State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Donghu Nanlu No 7, Wuhan 430072 (China)]. E-mail: lrsong@ihb.ac.cn; Gan Nanqin [State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Donghu Nanlu No 7, Wuhan 430072 (China); Li Lin [State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Donghu Nanlu No 7, Wuhan 430072 (China)

    2006-12-15

    In the present paper, sorption, persistence, and leaching behavior of three microcystin variants in Chinese agriculture soils were examined. Based on this study, the values of capacity factor and slope for three MCs variants in three soils ranged from 0.69 to 6.00, and 1.01 to 1.54, respectively. The adsorption of MCs in the soils decreased in the following order: RR>Dha{sup 7} LR>LR. Furthermore, for each MC variant in the three soils, the adsorption rate in the soils decreased in the following order: soil A>soil C>soil B. The calculated half-time ranged between 7.9 and 17.8 days for MC-RR, 6.0-17.1 days for MC-LR, and 7.1-10.2 days for MC-Dha{sup 7} LR. Results from leaching experiments demonstrated that recoveries of toxins in leachates ranged from 0-16.7% for RR, 73.2-88.9% for LR, and 8.9-73.1% for Dha{sup 7} LR. The GUS value ranged from 1.48 to 2.06 for RR, 1.82-2.88 for LR, and 1.76-2.09 for Dha{sup 7} LR. Results demonstrated the use of cyanobacterial collections as plant fertilizer is likely to be unsafe in soils. - The use of cyanobacterial blooms as plant fertilizer is likely to be unsafe in soils.

  19. 不同灌溉方式下枣树根区土壤洗盐效果试验%Soil Salt-washing Effect of Different Irrigation Modes in the Oasis Agriculture Region of Desert with Red Jujube

    Institute of Scientific and Technical Information of China (English)

    王兴鹏; 严晓燕; 李宁; 张军

    2011-01-01

    在不同的灌溉方式及灌水量条件下,对红枣根区的洗盐效果开展了试验研究,研究结果表明,当灌水量分别为30 L和40 L时,滴灌和坑灌的洗盐效果最佳区城在1040 cm土层内,但同时增加了4060 cm红枣根系层土壤盐分的累积程度,会对红枣的生长发育产生不利.而注灌对红枣根系层4060 cm的洗盐优势较为明显,洗盐效果最佳的注灌水量为2530 L.在相同的淋洗水童条件下,红枣根系区的洗盐效果大小依次为注灌、坑灌、滴灌.但当达到最佳的根系层洗盐效果时,注灌所用的淋洗水量要远远小于其他2种方式.%This paper studied on the salt-washing effect of the Red Jujube by different irrigation modes and different amount of water. The results showed that, when the amount of irrigation water was respectively 30 L and 40 L, the optimal area of drip-irrigation and pit irrigation was 10~40 cm in soil layer. But at the same time, would increase the accumulation of the soil-salt around the 40~60 cm fruit tree root, which would engender disadvantage for the development of the red jujube. But the advantage of injection irrigation was more obvious, especially in the soil of 40~60 cm, the best amount of the water was 25~30 L.On the same washing condition, the best irrigation was injection-irrigation, and than pit-irrigation, drip-irrigation at the last. But when reached to the best effect of salt-washing, the amount of the water using of injection-irrigation was less than others.

  20. Assessment of groundwater, soil-gas, and soil contamination at the Vietnam Armor Training Facility, Fort Gordon, Georgia, 2009-2011

    Science.gov (United States)

    Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2012-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the groundwater, soil gas, and soil for contaminants at the Vietnam Armor Training Facility (VATF) at Fort Gordon, from October 2009 to September 2011. The assessment included the detection of organic compounds in the groundwater and soil gas, and inorganic compounds in the soil. In addition, organic contaminant assessment included organic compounds classified as explosives and chemical agents in selected areas. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. This report is a revision of "Assessment of soil-gas, surface-water, and soil contamination at the Vietnam Armor Training Facility, Fort Gordon, Georgia, 2009-2010," Open-File Report 2011-1200, and supersedes that report to include results of additional samples collected in July 2011. Four passive samplers were deployed in groundwater wells at the VATF in Fort Gordon. Total petroleum hydrocarbons and benzene and octane were detected above the method detection level at all four wells. The only other volatile organic compounds detected above their method detection level were undecane and pentadecane, which were detected in two of the four wells. Soil-gas samplers were deployed at 72 locations in a grid pattern across the VATF on June 3, 2010, and then later retrieved on June 9, 2010. Total petroleum hydrocarbons were detected in 71 of the 72 samplers (one sampler was destroyed in the field and not analyzed) at levels above the method detection level, and the combined mass of benzene, toluene, ethylbenzene, and total xylene (BTEX) was detected above the detection level in 31 of the 71 samplers that were analyzed. Other volatile organic compounds

  1. Adsorptive properties of alluvial soil for arsenic(V) and its potential for protection of the shallow groundwater among Changsha, Zhuzhou, and Xiangtan cities, China.

    Science.gov (United States)

    Chen, Hongwei; Mei, Jinhua; Luo, Yueping; Qiu, Anni; Wang, Huan

    2017-02-01

    The study area is among Changsha, Zhuzhou, and Xiangtan cities, which was under agricultural use and natural conditions about 10 years ago and now is becoming part of the metropolis because of the urban expansion. This study aims to investigate the mechanisms and capabilities of the local alluvial soil layer for protecting the local shallow groundwater from arsenic pollution by field surveys and batch experiments. The field surveys showed that there was an acidic tendency of the groundwater, and phosphate, nitrate, and arsenic in the groundwater significantly increased comparing to their reference values. It indicates that the disturbance of the former agricultural land due to the change of land use may be responsible for these changes. From the experimental results, the maximum adsorption capacity of the soil for As(V) was as low as 0.334 mg/g, and lower As(V) adsorption capacities were obtained at higher As(V) concentration, higher pH, and lower temperature. The presence of H2PO4(-) and SiO3(2-) posed negative, while HCO3(-) slight positive, and SO4(2-), NO3(-) and Cl(-) negligible influences on the As(V) adsorption. The surface-derived organic matter played a negative role in the adsorption process, and low specific surface area influenced adsorption capacity of the soil. The study reveals that the local soil layer shows poor potential for protection of the local shallow groundwater from As(V) pollution, and the change trends of the groundwater environments due to more intensive anthropogenic activities will further weaken this potential and increase the risk of the groundwater contamination.

  2. Optimization of Technological Conditions for Remediation of Heavy Metal Contaminated Soil by Rhamnolipid Washing%鼠李糖脂淋洗修复重金属污染土壤的工艺条件优化研究

    Institute of Scientific and Technical Information of China (English)

    李尤; 廖晓勇; 阎秀兰; 龚雪刚

    2015-01-01

    以湖南某冶炼厂周边重金属-砷复合污染土壤为对象,应用表面活性剂鼠李糖脂为主要淋洗剂,研究了不同pH值、温度和淋洗次数等工艺条件对重金属及砷淋洗效果的影响。结果表明:Zn、Cd、As在淋洗剂pH为2时提取能力最高,分别可达397、30、21 mg·kg-1,但Cu的洗脱能力随着pH值的升高而增加;淋洗剂对Cd、Zn、Cu、As的洗脱能力在40℃时达到最大值,在30℃时淋洗液中Pb浓度最高,为54 mg·kg-1;多次淋洗有助于土壤中重金属及砷的洗脱,Pb、Cd、Zn、Cu、As的3次淋洗效率分别可达23.1%、53.8%、44.7%、63.2%和34.4%;淋洗后土壤中重金属的酸可提取态、氧化物结合态及有机物结合态浓度大幅降低,砷的残渣态和氧化物结合态浓度明显下降。试验研究确定的最优淋洗条件为污染土壤淋洗修复工程应用提供了可借鉴的工艺参数。%Rhamnolipid biosurfactant has showed to be effective in removing heavy metals from soils. Here a study was initiated to optimize pH, temperature and washing time for removal of heavy metals and arsenic by rhamnolipid from contaminated soil collected from a smeltery in Hunan. At solution pH 2, the extraction of Zn, Cd, and As was the greatest, which was 397, 30, and 21 mg·kg-1, respectively. However, the washing rates of Cu increased with increasing pH values. At the temperature of 40℃, the maximum elution for Cd, Zn, Cu, and As was obtained, which was 36, 438, 33, and 29 mg·kg-1, respectively, whereas the highest leaching concentration of Pb(54 mg·kg-1)was obtained at 30℃. Three successive washing cycles with the mixture solutions of rahmnolipid and HCl were shown to remove 23.10%of Pb, 53.78%of Cd, 44.74%of Zn, 63.19%of Cu, and 34.37%of As. Successive washing resulted in significant declines in acid extractable, oxides bound and organic bound heavy metals, while in residual and oxides bound arsenic. The present results

  3. Occurrence and source analysis of typical veterinary antibiotics in manure, soil, vegetables and groundwater from organic vegetable bases, northern China

    Energy Technology Data Exchange (ETDEWEB)

    Hu Xiangang [Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China); Zhou Qixing, E-mail: huxiangang@mail.nankai.edu.c [Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China); Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Luo Yi [Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China)

    2010-09-15

    The residue of antibiotics is becoming an intractable environmental problem in many organic vegetable bases. However, their residual levels and distribution are still obscure. This work systematically analyzed the occurrence and migration of typical veterinary antibiotics in organic vegetable bases, northern China. The results showed that there was no obvious geographical difference in antibiotic distribution between soil and manure. A simple migration model can be easy and quick to predict the accumulation of antibiotics in soil. Antibiotics were mainly taken up through water transport and passive absorption in vegetables. The distribution of antibiotics in a plant was in the sequence leaf > stem > root, and performed biological accumulation. The residues of antibiotics in all samples in winter were significantly higher than those in summer. Overall, this work can lay the foundation for understanding ecological risk of antibiotics and their potential adverse effects on human health by food chain. - The residues of typical veterinary antibiotics from manure were detected and migrated in soil, vegetables and groundwater of organic vegetable bases.

  4. Ecotoxicological assessment of the potential impact on soil porewater, surface and groundwater from the use of organic wastes as soil amendments.

    Science.gov (United States)

    Alvarenga, Paula; Mourinha, Clarisse; Farto, Márcia; Palma, Patrícia; Sengo, Joana; Morais, Marie-Christine; Cunha-Queda, Cristina

    2016-04-01

    This study aimed to assess the potential impact on soil porewater, surface and groundwater from the beneficial application of organic wastes to soil, using their eluates and acute bioassays with aquatic organisms and plants: luminescence inhibition of Vibrio fischeri (15 and 30 min), Daphnia magna immobilization (48 h), Thamnocephalus platyurus survival (24 h), and seed germination of Lolium perenne (7 d) and Lactuca sativa (5 d). Some organic wastes' eluates promoted high toxic responses, but that toxicity could not be predicted by their chemical characterization, which is compulsory by regulatory documents. In fact, when organisms were exposed to the water-extractable chemical compounds of the organic wastes, the toxic responses were more connected to the degree of stabilization of the organic wastes, or to the treatment used to achieve that stabilization, than to their contaminant load. That is why the environmental risk assessment of the use of organic wastes as soil amendments should integrate bioassays with eluates, in order to correctly evaluate the effects of the most bioavailable fraction of all the chemical compounds, which can be difficult to predict from the characterization required in regulatory documents. According to our results, some rapid and standardized acute bioassays can be suggested to integrate a Tier 1 ecotoxicological evaluation of organic wastes with potential to be land applied, namely luminescence inhibition of V. fischeri, D. magna immobilization, and the germination of L. perenne and L. sativa.

  5. In situ bioremediation of nitrate and perchlorate in vadose zone soil for groundwater protection using gaseous electron donor injection technology.

    Science.gov (United States)

    Evans, Patrick J; Trute, Mary M

    2006-12-01

    When present in the vadose zone, potentially toxic nitrate and perchlorate anions can be persistent sources of groundwater contamination. Gaseous electron donor injection technology (GEDIT), an anaerobic variation of petroleum hydrocarbon bioventing, involves injecting electron donor gases, such as hydrogen or ethyl acetate, into the vadose zone, to stimulate biodegradation of nitrate and perchlorate. Laboratory microcosm studies demonstrated that hydrogen and ethanol promoted nitrate and perchlorate reduction in vadose zone soil and that moisture content was an important factor. Column studies demonstrated that transport of particular electron donors varied significantly; ethyl acetate and butyraldehyde were transported more rapidly than butyl acetate and ethanol. Nitrate removal in the column studies, up to 100%, was best promoted by ethyl acetate. Up to 39% perchlorate removal was achieved with ethanol and was limited by insufficient incubation time. The results demonstrate that GEDIT is a promising remediation technology warranting further validation.

  6. Geochemical characterisation of pyrite oxidation and environmental problems related to release and transport of metals from a coal washing low-grade waste dump, Shahrood, northeast Iran.

    Science.gov (United States)

    Doulati Ardejani, Faramarz; Jodieri Shokri, Behshad; Moradzadeh, Ali; Shafaei, Seyed Ziadin; Kakaei, Reza

    2011-12-01

    Pyrite oxidation and release of the oxidation products from a low-grade coal waste dump to stream, groundwater and soil was investigated by geochemical and hydrogeochemical techniques at Alborz Sharghi coal washing plant, Shahrood, northeast Iran. Hydrogeochemical analysis of water samples indicates that the metal concentrations in the stream waters were low. Moreover, the pH of the water showed no considerable change. The analysis of the stream water samples shows that except the physical changes, pyrite oxidation process within the coal washing waste dump has not affected the quality of the stream water. Water type was determined to be calcium sulphate. The results of the analysis of groundwater samples indicate that the pH varies from 7.41 to 7.51. The concentrations of the toxic metals were low. The concentration of SO4 is slightly above than its standard concentration in potable water. It seems that the groundwater less affected by the coal washing operation in the study area. Geochemical analysis of the sediment samples shows that Fe concentration decreases gradually downstream the waste dump with pH rising. SO(4) decreases rapidly downstream direction. Copper, Zn and Co concentrations decrease with distance from the waste dump due to a dilution effect by the mixing of uncontaminated sediments. These elements, in particular, Zn are considerably elevated in sediment sample collected at the nearest distance to the waste dump. There is no doubt that such investigations can help to develop an appropriate water remediation plan.

  7. Overview of Research on Remediation of Oil-contaminated Soil by Surfactant Ex-situ Washing Method%表面活性剂异位淋洗法修复石油污染土壤

    Institute of Scientific and Technical Information of China (English)

    冉德钦; 程建安; 于佳宏; 张伟娜; 殷永泉; 崔兆杰

    2012-01-01

    综述了表面活性剂在石油污染土壤修复中的应用情况,介绍了表面活性剂的卷缩和增溶作用机理,分析了在异位淋洗修复中的表面活性剂浓度、复配等影响因素,并对表面活性剂在石油污染土壤修复领域的研究和应用前景进行了展望.%The application status of surfactant in remediation of oil-contaminated soil is reviewed. The mechanisms of rolling-up and solubilization by surfactant are introduced. The affecting factors such as surfactant concentration and compounded system in ex-situ washing remediation are analyzed. Finally, the prospects of further research are presented.

  8. Treatment of sediments from soil washing plants. Investigation of the suitability of a gas/solids fluidized bed bioreactor for the decontamination; Bodenwaschanlagen-Sedimente behandeln. Untersuchungen der Eignung des Gas/Feststoff-Wirbelschicht-Bioreaktors zur Dekontaminierung

    Energy Technology Data Exchange (ETDEWEB)

    Behns, W.; Haida, H. [Magdeburg Univ. (Germany). Inst. fuer Apparate- und Umwelttechnik; Friedrich, C. [Allgaier-Werke, Uhingen (Germany)

    1997-09-01

    This article deals with the possibility of microbiological decontamination of sediments from soil washing plants in gas/solids fluidized bed bioreactors. The sediments are pressed to granulates. The pollutants which are removed are mineral oil hydrocarbons. The degradation results of this process are presented, the process seems to be an alternative to common waste treatment processes. (SR) [Deutsch] Die mikrobiologische Dekontaminierung sandiger Boeden in einem Gas/Feststoff-Wirbelschicht-Bioreaktor ist eine erfolgversprechende Alternative zu anderen biologischen Reinigungsverfahren. Die biologische Dekontaminierung von Schlufffraktionen oder von Bodenwaschanlagensedimenten (BWS) ist deutlich schwieriger. In der Literatur werden vor allem Verfahren unter Einsatz von Suspensionsreaktoren verwendet, um fuer Feinkorn-Fraktionen eine biologische Reinigung zu ermoeglichen. Hier soll ueber Untersuchungen berichtet werden, mit denen die Eignung des Gas/Feststoff-Wirbelschicht-Bioreaktors fuer die Dekontaminierung derartiger Boeden ueberprueft werden sollte. (orig.)

  9. Quantifying effects of soil heteogeneity on groundwater pollution at four sites in USA

    NARCIS (Netherlands)

    Vuurens, S.H.; Stagnitti, F.; Rooij, de G.H.; Boll, J.; Ling, Li; LeBlanc, M.; Ierodiaconou, D.; Versace, V.; Salzman, S.

    2005-01-01

    Four sites located in the north-eastern region of the United States of America have been chosen to investigate the impacts of soil heterogeneity in the transport of solutes (bromide and chloride) through the vadose zone (the zone in the soil that lies below the root zone and above the permanent satu

  10. An Improved GRACE Terrestrial Water Storage Assimilation System For Estimating Large-Scale Soil Moisture and Shallow Groundwater

    Science.gov (United States)

    Girotto, M.; De Lannoy, G. J. M.; Reichle, R. H.; Rodell, M.

    2015-12-01

    The Gravity Recovery And Climate Experiment (GRACE) mission is unique because it provides highly accurate column integrated estimates of terrestrial water storage (TWS) variations. Major limitations of GRACE-based TWS observations are related to their monthly temporal and coarse spatial resolution (around 330 km at the equator), and to the vertical integration of the water storage components. These challenges can be addressed through data assimilation. To date, it is still not obvious how best to assimilate GRACE-TWS observations into a land surface model, in order to improve hydrological variables, and many details have yet to be worked out. This presentation discusses specific recent features of the assimilation of gridded GRACE-TWS data into the NASA Goddard Earth Observing System (GEOS-5) Catchment land surface model to improve soil moisture and shallow groundwater estimates at the continental scale. The major recent advancements introduced by the presented work with respect to earlier systems include: 1) the assimilation of gridded GRACE-TWS data product with scaling factors that are specifically derived for data assimilation purposes only; 2) the assimilation is performed through a 3D assimilation scheme, in which reasonable spatial and temporal error standard deviations and correlations are exploited; 3) the analysis step uses an optimized calculation and application of the analysis increments; 4) a poor-man's adaptive estimation of a spatially variable measurement error. This work shows that even if they are characterized by a coarse spatial and temporal resolution, the observed column integrated GRACE-TWS data have potential for improving our understanding of soil moisture and shallow groundwater variations.

  11. Effects of irrigated agroecosystems: 1. Quantity of soil water and groundwater in the southern High Plains, Texas

    Science.gov (United States)

    Scanlon, B. R.; Reedy, R. C.; Gates, J. B.

    2010-09-01

    Although irrigated agriculture is the primary consumer of global groundwater resources, information on recharge rates and sustainable irrigation is limited. The study objective was to fingerprint irrigation return flow to quantify percolation/recharge and to estimate sustainable irrigation levels. This paper focuses on water quantity; a companion paper addresses water quality. Soil samples from 13 boreholes drilled beneath irrigated agroecosystems in the southern High Plains were analyzed for matric potential and water-extractable Cl and NO3. Unsaturated zone pore water beneath irrigated agroecosystems can be fingerprinted by higher matric potentials (wetter soils, median mp: -40 m) and higher NO3-N (median 71 mg/L) than beneath natural ecosystems (mp -200 m; NO3-N 8.1 mg/L) and by higher Cl (720 mg/L) than beneath rain-fed agroecosystems (8.4 mg/L). The range in percolation/recharge rates beneath irrigated agroecosystems is 18-97 mm/a (median 41 mm/a; 5% of irrigation + precipitation) and occurs primarily in response to extreme precipitation events. Similarity in percolation/recharge rates beneath irrigated and rain-fed (4.8-92 mm/a) agroecosystems was unexpected and is attributed to low irrigation applications (median 300 mm/a) and increased crop yield and evapotranspiration in irrigated areas. Regional water table declines are unsustainably large (≥ 30 m over 10,000 km2) in the north and are much lower in the south. Sustainable irrigation in the south would require reduction of the irrigated area from 23% to 9%. Methods developed for quantifying recharge and sustainable irrigation application rates can be applied to groundwater-fed irrigated areas in semiarid regions globally.

  12. Biotechnology Workgroup for Department of Defense Soil and Groundwater Decontamination Application

    Science.gov (United States)

    1991-06-01

    biotransfor - mation rates. 2.3.5 Develop In-Situ Methods for Assessing Microbiological Activity; Priority 6, a 6.2 and 6.3 Project Background: In order...2.5.6 Heavy Metals Speciation in DERA/Superfund Sites; Priority Level 4 ) Background: Impact, toxicity and degree of bioaccumulation ...groundwater. "* Ability to predict the bioaccumulation /biomagnification of metal species. 0 "* Cost-effective cleanup of hazardous waste sites contaminated

  13. The use of vinasse as an amendment to ex-situ bioremediation of soil and groundwater contaminated with diesel oil

    Directory of Open Access Journals (Sweden)

    Adriano Pinto Mariano

    2009-08-01

    Full Text Available This work investigated the possibility of using vinasse as an amendment in ex-situ bioremediation processes. Groundwater and soil samples were collected at petrol stations. The soil bioremediation was simulated in Bartha biometer flasks, used to measure the microbial CO2 production, during 48 days, where vinasse was added at a concentration of 33 mL.Kg-1of soil. Biodegradation efficiency was also measured by quantifying the total petroleum hydrocarbons (TPH by gas chromatography. The groundwater bioremediation was carried out in laboratory experiments simulating aerated (bioreactors and not aerated (BOD flasks conditions. In both the cases, the concentration of vinasse was 5 % (v/v and different physicochemical parameters were evaluated during 20 days. Although an increase in the soil fertility and microbial population were obtained with the vinasse, it demonstrated not to be adequate to enhance the bioremediation efficiency of diesel oil contaminated soils. The addition of the vinasse in the contaminated groundwaters had negative effects on the biodegradation of the hydrocarbons, since vinasse, as a labile carbon source, was preferentially consumed.Este trabalho investigou a possibilidade de se usar a vinhaça como um agente estimulador de processos de biorremediação ex-situ. Amostras de água subterrânea e solo foram coletadas em três postos de combustíveis. A biorremediação do solo foi simulada em frascos de Bartha, usados para medir a produção de CO2, durante 48 dias, onde a vinhaça foi adicionada a uma concentração de 33 mL.Kg-1 de solo. A eficiência de biodegradação também foi medida pela quantificação de hidrocarbonetos totais de petróleo (TPH por cromatografia gasosa. A biorremediação da água subterrânea foi realizada em experimentos laboratoriais simulando condições aeradas (bioreatores e não aeradas (frascos de DBO. Em ambos os casos, a concentração de vinhaça foi de 5 % (v/v e diferentes parâmetros f

  14. The influence of groundwater flow effect on changes of loess soil strength characteristics

    Directory of Open Access Journals (Sweden)

    Bida S.V.

    2015-09-01

    Full Text Available The problem of stability of slopes - one of the most topical at present. It is proved that the reliability of the slope stability assessment affects the accuracy of the strength characteristics of the soil. One of the most common methods is one-plane shifts method Established that processing of results of soil shift test in logarithmic coordinates can more accurately identify indicators of strength. Discovered that the magnitude of the strength characteristics of soil test results which is obtained on one plane shift depends on the vertical pressure during testing.

  15. Quantifying phosphorus levels in soils, plants, surface water, and shallow groundwater associated with bahiagrass-based pastures.

    Science.gov (United States)

    Sigua, Gilbert C; Hubbard, Robert K; Coleman, Samuel W

    2010-01-01

    Recent assessments of water quality status have identified eutrophication as one of the major causes of water quality 'impairment' not only in the USA but also around the world. In most cases, eutrophication has accelerated by increased inputs of phosphorus due to intensification of crop and animal production systems since the early 1990 s. Despite substantial measurements using both laboratory and field techniques, little is known about the spatial and temporal variability of phosphorus dynamics across landscapes, especially in agricultural landscapes with cow-calf operations. Critical to determining environmental balance and accountability is an understanding of phosphorus excreted by animals, phosphorus removal by plants, acceptable losses of phosphorus within the manure management and crop production systems into soil and waters, and export of phosphorus off-farm. Further research effort on optimizing forage-based cow-calf operations to improve pasture sustainability and protect water quality is therefore warranted. We hypothesized that properly managed cow-calf operations in subtropical agroecosystem would not be major contributors to excess loads of phosphorus in surface and ground water. To verify our hypothesis, we examined the comparative concentrations of total phosphorus among soils, forage, surface water, and groundwater beneath bahiagrass-based pastures with cow-calf operations in central Florida, USA. Soil samples were collected at 0-20; 20-40, 40-60, and 60-100 cm across the landscape (top slope, middle slope, and bottom slope) of 8 ha pasture in the fall and spring of 2004 to 2006. Forage availability and phosphorus uptake of bahiagrass were also measured from the top slope, middle slope, and bottom slope. Bi-weekly (2004-2006) groundwater and surface water samples were taken from wells located at top slope, middle slope, and bottom slope, and from the runoff/seepage area. Concentrations of phosphorus in soils, forage, surface water, and shallow

  16. Cone Penetration Test and Soil Boring at the Bayside Groundwater Project Site in San Lorenzo, Alameda County, California

    Science.gov (United States)

    Bennett, Michael J.; Sneed, Michelle; Noce, Thomas E.; Tinsley, John C.

    2009-01-01

    Aquifer-system deformation associated with ground-water-level changes is being investigated cooperatively by the U.S. Geological Survey (USGS) and the East Bay Municipal Utility District (EBMUD) at the Bayside Groundwater Project (BGP) near the modern San Francisco Bay shore in San Lorenzo, California. As a part of this project, EBMUD has proposed an aquifer storage and recovery (ASR) program to store and recover as much as 3.78x104 m3/d of water. Water will be stored in a 30-m sequence of coarse-grained sediment (the 'Deep Aquifer') underlying the east bay alluvium and the adjacent ground-water basin. Storing and recovering water could cause subsidence and uplift at the ASR site and adjacent areas because the land surface will deform as aquifers and confining units elastically expand and contract with ASR cycles. The Deep Aquifer is overlain by more than 150 m of clayey fine-grained sediments and underlain by comparable units. These sediments are similar to the clayey sediments found in the nearby Santa Clara Valley, where inelastic compaction resulted in about 4.3 m of subsidence near San Jose from 1910 to 1995 due to overdraft of the aquifer. The Deep Aquifer is an important regional resource, and EBMUD is required to demonstrate that ASR activities will not affect nearby ground-water management, salinity levels, or cause permanent land subsidence. Subsidence in the east bay area could induce coastal flooding and create difficulty conveying winter storm runoff from urbanized areas. The objective of the cooperative investigation is to monitor and analyze aquifer-system compaction and expansion, as well as consequent land subsidence and uplift resulting from natural causes and any anthropogenic causes related to ground-water development and ASR activities at the BGP. Therefore, soil properties related to compressibility (and the potential for deformation associated with ground-water-level changes) are of the most concern. To achieve this objective, 3 boreholes

  17. Impact of soil and groundwater corrosion on the Hierakonpolis Temple Town archaeological site, Wadi Abu Sufian, Idfu, Egypt.

    Science.gov (United States)

    El-Shishtawy, A M; Atwia, M G; El-Gohary, A; Parizek, R R

    2013-06-01

    Hierakonpolis, Greek for City of the Hawk, nearly 25 km NW of Idfu (Egypt), is an important and extensive archaeological discovery covering a large area. Its richness in archaeological artifacts makes it a valuable site. It has a valid claim to be the first nation state, as indicated by the Palette of Narmer discovered in its main mound. Geological and hydrogeological investigations at the Hierakonpolis Temple Town site documented nearly a 4.0-m water table rise from as early as 1892 to the present. In addition to the rising water levels, the increase of both subsoil water salinity and humidity threatens and damages fragile carvings and paintings within tombs in Kingdom Hill, the foundation stability of the site, and the known and still to be discovered artifact that recent pottery finds dates at least 4,000 BCE. Representative rock and soil samples obtained from drilled cores in the study area were chosen for conducting detailed grain size and X-ray analysis, light and heavy mineral occurrences, distribution of moisture and total organic matter, and scanning electron microscopy investigations. Mineralogical analysis of clays indicated that the soil samples are composed of smectite/illite mixed layers with varying proportions of smectite to illite. Kaolinite is the second dominant clay constituent, besides occasional chlorite. Swelling of the clay portion of the soil, due to the presence of capillary groundwater, in contact with buried mudbrick walls expands and causes severe damage to important exposed and buried mudbrick structures, including the massive ancient "fort" believed to date from the Second Dynasty (from 2,890 to 2,686 BC). The "fort" is 1.0 km south of the Temple Town mounds near to confluence of Wadi Abu Sufian. Groundwater samples from the shallow aquifer close by the intersection of Wadi Abu Sufian and the Nile flood plain were analyzed for chemical composition and stable isotope ratios. The groundwater in the upper zone (subsoil water) within fine

  18. Investigating an Inverted Soil Column in Northern Tanzania: Could Intense Groundwater Weathering be the Culprit?

    Science.gov (United States)

    Little, M. G.; Lee, C. A.

    2004-12-01

    Weathering of silicate rocks permanently sequesters a significant amount CO2 on our planet (Berner et al., 1983; Dessert et al., 2003; Gaillardet et al., 1999). Therefore, the investigation of soils and their conjugate protoliths have implications for a wide range of disciplines from soil to atmospheric sciences. This study investigates soil formed in Northern Tanzania on the southern slope of the dormant volcano Mt. Kilimanjaro. Our sample site is in the Machame region at an elevation of ~1640 m where the phonotephrite to basaltic bedrock has been dated at 0.4 to 0.5 million years (Evernden and Curtis, 1965). We determined bulk elemental concentrations of soil and bedrock samples from this region using an ICP-MS and XRF. From initial investigations into the bulk soil and bedrock chemistry using a novel mass balance method, we were able to investigate the relative mobility of a suite of elements. Relative abundances of Ta, Nb, Hf, and Zr are constant and therefore these elements are immobile. In contrast, Ti, an element commonly thought to be immobile, is clearly not immobile in our samples. The entire soil column appears to be highly depleted in Si and Ca but enriched in Al. These features indicate extensive weathering and indeed some samples approach bauxite compositions. Surprisingly, however, weathering versus depth is reversed. Si and Ca have been removed by 60 and 70 % respectively from the upper 2 meters, but below 2 m, they have been removed by 95 and 99 %. This means that the soil is more weathered at depth than in the shallowest 2 meters. We believe that ground water weathering is responsible for this inverted soil profile and may increase CO2 consumption estimates by 10-30 % for similarly affected basalts.

  19. Investigation of Chromium and Nickel mobility in serpentinite soils and rocks: Impact into groundwaters and influences of carbonation.

    Science.gov (United States)

    Baneschi, Ilaria; Natali, Claudio; Boschi, Chiara; Chiarantini, Laura; Guidi, Massimo

    2013-04-01

    Potentially harmful elements such as Cr and Ni in soils are increasingly drawing the attention of scientists and authorities due to their potential toxicity to humans and ecosystems. In the Tuscany region high levels of Cr in Ni have been reported in ultramafic rocks and soils. Furthermore, concentrations of Cr in groundwater of several aquifer systems of this area can approach the maximum contamination level of 50 µg/l, mainly in the form of Cr (VI). The main mechanism for mobilization Cr (VI) at these sites is the weathering of Cr (III) from ultramafic rock with subsequent oxidation. To characterize the effects of weathering and the accessibility of geologically sourced and potentially toxic Cr and Ni in coastal Tuscany EU and Regione Toscana financed a multidisciplinary project, named RESPIRA. The study of waters, rocks and soils was conducted in the some sites of the coastal area of Tuscany, where concentrations of Cr (VI) in springwaters are around 50 µg/l (like in Querceto and Montecastelli) or below the detection limit, such as in Santa Luce. It has to be noted that at the site of Montecastelli and Querceto carbonation of serpentinite outcrops has been revealed (Boschi, 2011), together with iron rich brucite. Chemical and mineralogical analyses were conducted on rock and soil samples by scanning electron microscopy (SEM), electron microprobe (EMP), X-Ray Fluorescence (XRF) and seven-steps sequential extraction. Extraction analyses were performed to obtain quantitative information on the distribution of trace metals in different mineralogical phases (clay minerals, carbonates, amorphous Fe, Mn oxides, organic matter and other silicates and oxides). The results show that the residual fraction was the predominant form of Cr and Ni in soil and rock samples. However, the concentrations of Ni associated to exchangeable, carbonates, Mn oxides and non cristalline fractions were higher than those of Cr, indicating that Ni was more available than Cr in all samples

  20. Shallow groundwater and soil chemistry response to 3 years of subsurface drip irrigation using coalbed-methane-produced water

    Science.gov (United States)

    Bern, Carleton R.; Boehlke, Adam R.; Engle, Mark A.; Geboy, Nicholas J.; Schroeder, K.T.; Zupancic, J.W.

    2013-01-01

    Disposal of produced waters, pumped to the surface as part of coalbed methane (CBM) development, is a significant environmental issue in the Wyoming portion of the Powder River Basin, USA. High sodium adsorption ratios (SAR) of the waters could degrade agricultural land, especially if directly applied to the soil surface. One method of disposing of CBM water, while deriving beneficial use, is subsurface drip irrigation (SDI), where acidified CBM waters are applied to alfalfa fields year-round via tubing buried 0.92 m deep. Effects of the method were studied on an alluvial terrace with a relatively shallow depth to water table (∼3 m). Excess irrigation water caused the water table to rise, even temporarily reaching the depth of drip tubing. The rise corresponded to increased salinity in some monitoring wells. Three factors appeared to drive increased groundwater salinity: (1) CBM solutes, concentrated by evapotranspiration; (2) gypsum dissolution, apparently enhanced by cation exchange; and (3) dissolution of native Na–Mg–SO4 salts more soluble than gypsum. Irrigation with high SAR (∼24) water has increased soil saturated paste SAR up to 15 near the drip tubing. Importantly though, little change in SAR has occurred at the surface.

  1. A Novel Method for Analyzing Chlorine Isotope Fractionation for Source and Fate Assessment of Organochlorine Soil and Groundwater Pollutants

    Science.gov (United States)

    Aeppli, Christoph; Wiegert, Charline; Holmstrand, Henry; Andersson, Per; Gustafsson, Örjan

    2010-05-01

    We developed a simple and accurate analytical method for compound-specific determination of chlorine isotopic composition (δ37Cl) or organochlorines based on GC/MS analysis and standard isotope bracketing. Good accuracy (comparison with off-line thermal ionization mass spectrometry) and a precision comparable to other on-line δ37Cl-methods (0.6 permil vs SMOC) were achieved. We applied this method to assess biodegradation of polychlorinated phenols used for wood preservation at a former sawmill site in northern Sweden. To come up with a δ37Cl-based estimation of the importance of on-going aerobic microbial degradation, we analyzed 37Cl-enrichment during enzymatic dechlorination of polychlorinated phenols in laboratory experiments. We also investigated δ37Cl fingerprints of chloroperoxidase-mediated chlorinated phenols, which can be used for apportionment of natural and anthropogenic sources of chlorophenols in boreal soils. Furthermore, we investigated natural attenuation of chlorinated ethenes in a contaminated aquifer in the Czech Republic. At this site, the extent of naturally occurring reductive tetrachloroethene (PCE) dechlorination was estimated based on PCE-δ37Cl. Overall, our laboratory and field studies demonstrate the potential of using compound-specific chlorine isotope analysis for assessing the source and fate of organochlorine groundwater and soil contaminants.

  2. Shallow groundwater and soil chemistry response to 3 years of subsurface drip irrigation using coalbed-methane-produced water

    Energy Technology Data Exchange (ETDEWEB)

    Bern, C. R.; Boehlke, A. R.; Engle, M. A.; Geboy, N. J.; Schroeder, K. T.; Zupancic, J. W.

    2013-10-04

    Disposal of produced waters, pumped to the surface as part of coalbed methane (CBM) development, is a significant environmental issue in the Wyoming portion of the Powder River Basin, USA. High sodium adsorption ratios (SAR) of the waters could degrade agricultural land, especially if directly applied to the soil surface. One method of disposing of CBM water, while deriving beneficial use, is subsurface drip irrigation (SDI), where acidified CBM waters are applied to alfalfa fields year-round via tubing buried 0.92 m deep. Effects of the method were studied on an alluvial terrace with a relatively shallow depth to water table (~3 m). Excess irrigation water caused the water table to rise, even temporarily reaching the depth of drip tubing. The rise corresponded to increased salinity in some monitoring wells. Three factors appeared to drive increased groundwater salinity: (1) CBM solutes, concentrated by evapotranspiration; (2) gypsum dissolution, apparently enhanced by cation exchange; and (3) dissolution of native Na–Mg–SO{sub 4} salts more soluble than gypsum. Irrigation with high SAR (24) water has increased soil saturated paste SAR up to 15 near the drip tubing. Importantly though, little change in SAR has occurred at the surface.

  3. Wash Your Hands

    Centers for Disease Control (CDC) Podcasts

    2010-03-08

    This video shows kids how to properly wash their hands, one of the most important steps we can take to avoid getting sick and spreading germs to others.  Created: 3/8/2010 by Centers for Disease Control and Prevention (CDC).   Date Released: 3/8/2010.

  4. Wash Your Hands

    Science.gov (United States)

    ... don't have soap and clean, running water? Washing hands with soap and water is the best way to get rid of germs in most situations. If soap and water are not available, use an alcohol-based hand sanitizer [423 KB] that contains at least 60% alcohol. ...

  5. Hormones, sterols, and fecal indicator bacteria in groundwater, soil, and subsurface drainage following a high single application of municipal biosolids to a field.

    Science.gov (United States)

    Gottschall, N; Topp, E; Edwards, M; Payne, M; Kleywegt, S; Russell, P; Lapen, D R

    2013-04-01

    A land application of dewatered municipal biosolids (DMB) was conducted on an agricultural field in fall 2008 at a rate of 22Mg dry weight (dw) ha(-1). Pre- and post- application, hormone, sterol and fecal indicator bacteria concentrations were measured in tile drainage water, groundwater (2, 4, 6m depth), surface soil cores, and DMB aggregates incorporated in the soil (∼0.2m depth) for a period of roughly 1year post-application. Hormones and sterols were detected up to 1year post-application in soil and in DMB aggregates. Hormone (androsterone, desogestrel, estrone) contamination was detected briefly in tile water samples (22d and ∼2months post-app), at lowngL(-1) concentrations (2-34ngL(-1)). Hormones were not detected in groundwater. Sterols were detected in tile water throughout the study period post-application, and multiple fecal sterol ratios suggested biosolids as the source. Coprostanol concentrations in tile water peaked at >1000ngL(-1) (22d post-app) and were still >100ngL(-1) at 6months post-application. Fecal indicator bacteria were detected throughout the study period in tile water, groundwater (⩽2m depth), soil and DMB aggregate samples. These bacteria were strongly linearly related to coprostanol in tile water (R(2)>0.92, psterols to tile drainage networks may be attributed to a combination of the hydrophobicity of these compounds and limited macroporosity of the field soil. This transitory contamination from hormones and sterols is unlikely to result in any significant pulse exposure risk in subsurface drainage and groundwater. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  6. Elimination of urban wastewater by soil direct infiltration. Impact on soil solution-groundwater system; Eliminacion de aguas residuales urbanas mediante infiltracion directa sobre el terreno. Impacto sobre el sistema solucion del suelo-agua subterranea

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, L.; Murillo, J. M. [Instituto Tecnologico Geominero de Espana, Direccion de Aguas Subterraneas y Geotecnia. Madrid (Spain); Liquinano, M. C. [Universidad Complutense de Madrid (Spain); Rubio, J. C. [Instituto Tecnologico Geominero de Espana. Oficina Regional de Granada (Spain)

    2000-07-01

    Soil direct infiltration is, in small villages with no industrial spills, a viable, effective and low cost alternative to the conventional wastewater purification methods. In this paper, the evolution of soil solution and groundwater after almost one year of infiltration in an experimental plant for wastewater removal is shown. Soil solution has been sampled in great diameter wells with horizontal drains and groundwater is seven monitoring wells. Purification ratios reached in the samples taken at 3 meters depth are remarkable; so the suspended solids removal is over 90%, reduction of turbidity is always greater than 80%, BOD{sub 5} diminishing exceeds 90% and QOD 70% total organic carbon (TOC) average diminishing oscillates between 70% and 80%. Ammonium is effectively removed, between 67% and 88%. Phosphorous removal ratio is less then expected and it oscillates around 60%. (Author) 23 refs.

  7. Assessment of soil-gas and groundwater contamination at the Gibson Road landfill, Fort Gordon, Georgia, 2011

    Science.gov (United States)

    Falls, W. Fred; Caldwell, Andral W.; Guimaraes, Wladmir G.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2012-01-01

    Soil-gas and groundwater assessments were conducted at the Gibson Road landfill in 201 to provide screening-level environmental contamination data to supplement the data collected during previous environmental studies at the landfill. Passive samplers were used in both assessments to detect volatile and semivolatile organic compounds and polycyclic aromatic hydrocarbons in soil gas and groundwater. A total of 56 passive samplers were deployed in the soil in late July and early August for the soil-gas assessment. Total petroleum hydrocarbons (TPH) were detected at masses greater than the method detection level of 0.02 microgram in all samplers and masses greater than 2.0 micrograms in 13 samplers. Three samplers located between the landfill and a nearby wetland had TPH masses greater than 20 micrograms. Diesel was detected in 28 of the 56 soil-gas samplers. Undecane, tridecane, and pentadecane were detected, but undecane was the most common diesel compound with 23 detections. Only five detections exceeded a combined diesel mass of 0.10 microgram, including the highest mass of 0.27 microgram near the wetland. Toluene was detected in only five passive samplers, including masses of 0.65 microgram near the wetland and 0.85 microgram on the southwestern side of the landfill. The only other gasoline-related compound detected was octane in two samplers. Naphthalene was detected in two samplers in the gully near the landfill and two samplers along the southwestern side of the landfill, but had masses less than or equal to 0.02 microgram. Six samplers located southeast of the landfill had detections of chlorinated compounds, including one perchloroethene detections (0.04 microgram) and five chloroform detections (0.05 to0.08 microgram). Passive samplers were deployed and recovered on August 8, 2011, in nine monitoring wells along the southwestern, southeastern and northeastern sides of the landfill and down gradient from the eastern corner of the landfill. Six of the nine

  8. Impact of irrigation with high arsenic burdened groundwater on the soil-plant system: Results from a case study in the Inner Mongolia, China.

    Science.gov (United States)

    Neidhardt, H; Norra, S; Tang, X; Guo, H; Stüben, D

    2012-04-01

    Consequences of irrigation by arsenic (As) enriched groundwater were assigned in the Hetao Plain, part of Chinas' Inner Mongolia Autonomous Region. Examinations followed the As flow path from groundwater to soil and finally plants. A sunflower and a maize field were systematically sampled, each irrigated since three years with saline well water, characterized by elevated As concentrations (154 and 238μgL(-1)). The annual As input per m(2) was estimated as 120 and 186mg, respectively. Compared to the geogenic background, As concentrations increased toward the surface with observed enrichments in topsoil being relatively moderate (up to 21.1mgkg(-1)). Arsenic concentrations in plant parts decreased from roots toward leaves, stems and seeds. It is shown that the bioavailability of As is influenced by a complex interplay of partly counteracting processes. To prevent As enrichment and soil salinization, local farmers were recommended to switch to a less problematic water source.

  9. PREDICTING OF RISKS OF GROUNDWATER AND SURFACE WATER POLLUTION WITH DIFFERENT CLASSES OF HERBICIDES IN SOIL IN EASTERN EUROPE CLIMATE CONDITIONS.

    Science.gov (United States)

    Korshun, M; Dema, O; Kucherenko, O; Korshun, O; Garkavyi, S; Pelio, I; Antonenko, A; Velikaia, N

    2016-11-01

    Application of pesticides in modern agriculture is a powerful permanent risk factor for public health and the natural environment. The aim of the study was a comparative hygienic assessment of the danger of contamination of ground and surface water sources with most widely used herbicides of different chemical classes (sulfonylureas, imidazolinones, pirimidinilkarboksilovye compounds semicarbazones). Field hygienic experiments for studying of the residues dynamics of studied herbicides concentration in agrocenosis objects were made by us in different types of soils: chernozem, sod-podzolic, podzolized forest. Then the half-life periods (DT50) of the substances in the soil were calculated. It was found that according to GUS index there is a high probability of leaching into groundwater of sulfonylureas and imidazolinones; according to LEACH index all investigated substances have a high risk of run-off into groundwater and surface water.

  10. Distribution Patterns of PAHs in Soils from Coking Plant and the Particle-Size Cut Points of Soil Washing%焦化厂土壤中多环芳烃分布特征及淋洗粒级分割点确定

    Institute of Scientific and Technical Information of China (English)

    李合莲; 陈家军; 吴威; 朴雪松; 姜琳; 史震天; 孙添伟

    2011-01-01

    Soil particle size distribution and contaminants distribution patterns in different soil size fractions are the basis of soil treatability using soil washing method. Soil particle-size cut points are important parameters of soil washing process. According to ex situ soil washing technology, soil samples were collected in a former coking plant. The soil particle size distribution and the concentrations of 16 polycyclic aromatic hydrocarbons ( PAHs ) in USEPA priority list were analyzed. Tween 80 and Triton X- 100 solutions were used to clean the polluted soil with different particle size. Results showed that the total concentrations of 16 PAHs ranged from 6. 27 to 40. 18 mg/kg dry weight in the six soil size fractions and present a bimodal distribution. The maximum individual PAH concentration mostly occurred in the 250-500 μm size fraction. The lowest individual PAH concentration was in the 50-75 μ.m size fraction. The removal efficiencies of PAHs in different soil size fractions depended on their initial concentrations and the characteristics of soil. The PAHs removal efficiencies in coarser size fractions were lower than that in the finer size fractions owing to their higher organic carbon content. Based on the removal efficiency of PAHs in each soil size fractions by surfactant solution and the requirements of waste volume reduction, 50 μ.m was determined as the particle-size cut point. Then, 82.95% volume reduction can be achieved.%土壤粒径分布和污染物在不同粒级土壤中的分布特征是污染土壤淋洗可处理性的重要依据,淋洗粒级分割点则是淋洗工艺的重要参数,根据土壤异位淋洗的技术要求,在焦化厂污染场地进行了采样,测定了土样的粒径分布曲线及不同粒级土壤中美国EPA优控的16种多环芳烃(PAHs)的初始浓度,并采用Tween 80和Triton X-100溶液对不同粒级污染土样进行了振荡清洗实验.结果表明,16种PAHs在6个粒级中的总浓度在6.27~40.18 mg

  11. Soil water storage and groundwater behaviour in a catenary sequence beneath forest in central Amazonia: I. Comparisons between plateau, slope and valley floor

    Directory of Open Access Journals (Sweden)

    M. G. Hodnett

    1997-01-01

    Full Text Available Soil water storage was monitored in three landscape elements in the forest (plateau, slope and valley floor over a 3 year period to identify differences in sub-surface hydrological response. Under the plateau and slope, the changes of storage were very similar and there was no indication of surface runoff on the slope. The mean maximum seasonal storage change was 156 mm in the 2 m profile but it was clear that, in the dry season, the forest was able to take up water from below 3.6 m. Soil water availability was low. Soil water storage changes in the valley were dominated by the behaviour of a shallow water table which, in normal years, varied between 0.1 m below the surface at the end of the wet season and 0.8 m at the end of the dry season. Soil water storage changes were small because root uptake was largely replenished by groundwater flow towards the stream. The groundwater behaviour is controlled mainly by the deep drainage from beneath the plateau and slope areas. The groundwater gradient beneath the slope indicated that recharge beneath the plateau and slope commences only after the soil water deficits from the previous dry season have been replenished. Following a wet season with little recharge, the water table fell, ceasing to influence the valley soil water storage, and the stream dried up. The plateau and slope, a zone of very high porosity between 0.4 and 1.1 m, underlain by a less conductive layer, is a probable route for interflow during, and for a few hours after, heavy and prolonged rainfall.

  12. Groundwater discharge by evapotranspiration, flow of water in unsaturated soil, and stable isotope water sourcing in areas of sparse vegetation, Amargosa Desert, Nye County, Nevada

    Science.gov (United States)

    Moreo, Michael T.; Andraski, Brian J.; Garcia, C. Amanda

    2017-08-29

    This report documents methodology and results of a study to evaluate groundwater discharge by evapotranspiration (GWET) in sparsely vegetated areas of Amargosa Desert and improve understanding of hydrologic-continuum processes controlling groundwater discharge. Evapotranspiration and GWET rates were computed and characterized at three sites over 2 years using a combination of micrometeorological, unsaturated zone, and stable-isotope measurements. One site (Amargosa Flat Shallow [AFS]) was in a sparse and isolated area of saltgrass (Distichlis spicata) where the depth to groundwater was 3.8 meters (m). The second site (Amargosa Flat Deep [AFD]) was in a sparse cover of predominantly shadscale (Atriplex confertifolia) where the depth to groundwater was 5.3 m. The third site (Amargosa Desert Research Site [ADRS]), selected as a control site where GWET is assumed to be zero, was located in sparse vegetation dominated by creosote bush (Larrea tridentata) where the depth to groundwater was 110 m.Results indicated that capillary rise brought groundwater to within 0.9 m (at AFS) and 3 m (at AFD) of land surface, and that GWET rates were largely controlled by the slow but relatively persistent upward flow of water through the unsaturated zone in response to atmospheric-evaporative demands. Greater GWET at AFS (50 ± 20 millimeters per year [mm/yr]) than at AFD (16 ± 15 mm/yr) corresponded with its shallower depth to the capillary fringe and constantly higher soil-water content. The stable-isotope dataset for hydrogen (δ2H) and oxygen (δ18O) illustrated a broad range of plant-water-uptake scenarios. The AFS saltgrass and AFD shadscale responded to changing environmental conditions and their opportunistic water use included the time- and depth-variable uptake of unsaturated-zone water derived from a combination of groundwater and precipitation. These results can be used to estimate GWET in other areas of Amargosa Desert where hydrologic conditions are similar.

  13. Investigation of washing and storage strategy on aging Of Mg-aminoclay (MgAC) coated nanoscale zero-valent iron (nZVI) particles

    DEFF Research Database (Denmark)

    Hwang, Yuhoon; Lee, Young-Chul; Mines, Paul D.

    2014-01-01

    The tendency towards agglomeration and oxidation of nanoscale zero-valent iron (nZVI) particles limits its application for in situ groundwater and soil remediation. Although the effect of surface coatings on nanoparticle stabilization has been commonly practiced, the effect of preparation......, reactive iron content measured by H2 generation with acid digestion, and nitrate reduction capacity. All three parameters decrease significantly for post-storage washed nZVI, which corresponds to XRD results that exhibit transformation of Fe(0) to iron oxides. The reactivity tests display high linear...

  14. Please wash your hands often

    OpenAIRE

    2007-01-01

    This poster advises washing hands "before and after using the toilet, handling food, touching animals, eating, drinking, or smoking." It advocates "always use clean water / never wash your hands in used wash water!" The purpose is to protect self and others from diseases. LTRA-2 (An Agricultural Markets Model for Biodiversity Conservation)

  15. The Importance of Hand Washing

    Institute of Scientific and Technical Information of China (English)

    杨昌寿

    2004-01-01

    Medical experts say the most effective way to prevent the spread of diseases is for people to wash their hands with soap and water. The Word Bank and the United Nations carried out a study to urge hand washing around the world. They say programmes to increase hand washing with

  16. Salt overload: How quickly does road salt move from road to groundwater to stream in Baltimore County, MD and what are the effects on soil, groundwater, and stream chemistry?

    Science.gov (United States)

    Moore, J.; Sandosky, B.; McGuire, M.; Casey, R.; Snodgrass, J.; Lev, S. M.

    2013-12-01

    storm events. A persistent groundwater plume of water with high NaCl concentrations is present below the SMBs and downgradient in the shallow groundwater aquifer. Concentrations vary seasonally with the highest concentrations in the winter and early spring. Na+ clearly interacts with the cation exchange complex (CEC) along a flowpath between the SMB and the stream. As a result, the Na:Cl ratio falls from 1:1 in groundwater below the SMBs to as low as ~1:10 and also seems to vary seasonally along the flowpath. Preliminary measurements of the CEC show that the Ca:Na ratio decreases by a factor of 2 - 5 in soil and aquifer materials affected by road salt. Preliminary strontium (Sr) isotope data indicate that groundwater and CEC within the road salt plumes are similar to Sr isotope values for seawater and are isotopically distinct from the relatively radiogenic natural weathering Sr isotope signal. Our findings indicate that SMBs increase the residence time of road salt in groundwater and stream systems with potential negative implications for ecosystems downgradient of SMBs.

  17. Analytical results, database management and quality assurance for analysis of soil and groundwater samples collected by cone penetrometer from the F and H Area seepage basins

    Energy Technology Data Exchange (ETDEWEB)

    Boltz, D.R.; Johnson, W.H.; Serkiz, S.M.

    1994-10-01

    The Quantification of Soil Source Terms and Determination of the Geochemistry Controlling Distribution Coefficients (K{sub d} values) of Contaminants at the F- and H-Area Seepage Basins (FHSB) study was designed to generate site-specific contaminant transport factors for contaminated groundwater downgradient of the Basins. The experimental approach employed in this study was to collect soil and its associated porewater from contaminated areas downgradient of the FHSB. Samples were collected over a wide range of geochemical conditions (e.g., pH, conductivity, and contaminant concentration) and were used to describe the partitioning of contaminants between the aqueous phase and soil surfaces at the site. The partitioning behavior may be used to develop site-specific transport factors. This report summarizes the analytical procedures and results for both soil and porewater samples collected as part of this study and the database management of these data.

  18. Influence of groundwater on the degradation of irrigated soils in a semi-arid region, the inner delta of the Niger River, Mali

    Science.gov (United States)

    Valenza, A.; Grillot, J. C.; Dazy, J.

    2000-08-01

    The problem of soil degradation through alkalinization/salinization in an irrigated area with a semi-arid climate was examined in the inner delta of the Niger River, Mali, by the study of groundwater hydraulics and hydrochemistry in an area recharged by irrigation water. On the basis of data analysis on various scales, it is concluded that the current extent of the surface saline soils is due to a combination of three factors: (1) the existence of ancient saline soils (solonchaks) resulting from the creation of a broad sabkha west of the former course of the Niger River, now called the Fala of Molodo. These saline crusts were gradually deposited during the eastward tilting of the tectonic block that supports the Niger River; (2) the irrigation processes during the recent reflooding of the Fala of Molodo (river diversion in 1950). These used very poorly mineralized surface water but reintroduced into the alluvial groundwater system - generally of a low permeability (K=10-6 m s-1) - salts derived from the ancient solonchaks; and (3) the redeposition of the dissolved salts on the surface due to the intense evapotranspiration linked to the present Sahelian climate. In this context, only efficient artificial draining of subsurface alluvial groundwater can eliminate most of the highly mineralized flow and thus reduce the current saline deposits.

  19. Brominated flame retardants and perfluoroalkyl acids in groundwater, tile drainage, soil, and crop grain following a high application of municipal biosolids to a field.

    Science.gov (United States)

    Gottschall, N; Topp, E; Edwards, M; Payne, M; Kleywegt, S; Lapen, D R

    2017-01-01

    Dewatered municipal biosolids (DMB) were applied at a rate of 22Mgdwha(-1) to an agricultural field in fall 2008. Concentrations of polybrominated diphenyl ethers (PBDEs; BDE-47, -99, -100, -153, -154, -183, -197, -207, -209), other brominated flame retardants (BFRs; HBB, PBEB, DBDPE, BTBPE) and perfluoroalkyl acids (PFAAs; PFHxS, PFOS, PFDS, PFOSA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA, PFTA) were monitored in tile drainage, groundwater (2m, 4m and 6m depth), soil cores (0-0.3m) pre- and post-application, DMB aggregates incorporated into the soil post-application, and in wheat (Triticum spp.) planted post-application. Several compounds were detected in soil and water pre-application and on a reference field plot. PBDEs, other BFRs and PFAAs were detected in tile drainage and 2m groundwater throughout the post-application study period; a few PBDEs were also detected sporadically at lower depths in groundwater. Some of these compounds had not been detected pre-application, while some exceeded reference field plot/pre-application levels (some significantly (p90% in many of them within 1year post-application. Exponential dissipation of other BFRs and PFAAs in DMB aggregates were not significant. No PBDEs, other BFRs, or PFAAs were detected in wheat grain.

  20. Polar metabolites of polycyclic aromatic compounds from fungi are potential soil and groundwater contaminants

    DEFF Research Database (Denmark)

    Boll, Esther Sørensen; Johnsen, Anders R.; Christensen, Jan H.

    2015-01-01

    and either hydroxylated or oxidized to carboxylic acids at the methyl group. The metabolism of the sulfur-containing heterocyclic PAC resulted in sulfate conjugates. The sorption of the PAC metabolites to three soils was determined using a batch equilibrium method, and partition coefficients (Kd's) were......-methylphenanthrene, 1-methylpyrene), and one sulfur-containing heterocyclic PAC (dibenzothiophene). Fifty-eight metabolites were tentatively identified; metabolites from the un-substituted PACs were hydroxylated and sulfate conjugated, whereas metabolites from alkyl-substituted PACs were sulfate conjugated...... calculated for fourteen representative metabolites. Sulfate conjugated metabolites displayed Kd's below 70 whereas the metabolites with both a sulfate and a carboxylic acid group had Kd's below 2.8. The low Kd's of water-soluble PAC metabolites indicate high mobility in soil and a potential for leaching...

  1. The Development of a Sub-Surface Monitoring System for Organic Contamination in Soils and Groundwater

    Directory of Open Access Journals (Sweden)

    Sharon L. Huntley

    2002-01-01

    Full Text Available A major problem when dealing with environmental contamination is the early detection and subsequent surveillance of the contamination. This paper describes the potential of sub-surface sensor technology for the early detection of organic contaminants in contaminated soils, sediments, and landfill sites. Rugged, low-power hydrocarbon sensors have been developed, along with a data-logging system, for the early detection of phase hydrocarbons in soil. Through laboratory-based evaluation, the ability of this system to monitor organic contamination in water-based systems is being evaluated. When used in conjunction with specific immunoassays, this can provide a sensitive and low-cost solution for long-term monitoring and analysis, applicable to a wide range of field applications.

  2. Estimation of radon concentration in soil and groundwater samples of Northern Rajasthan, India

    Directory of Open Access Journals (Sweden)

    Sudhir Mittal

    2016-04-01

    Full Text Available In the present investigation, analysis of radon concentration in 20 water and soil samples collected from different locations of Bikaner and Jhunjhunu districts of Rajasthan, India has been carried out by using RAD7 an electronic Radon detector. The measured radon concentration in water samples lies in the range from 0.50 to 22 Bq l−1 with the mean value of 4.42 Bq l−1, which lies within the safe limit from 4 to 40 Bq l−1 recommended by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2008. The total annual effective dose estimated due to radon concentration in water ranges from 1.37 to 60.06 μSV y−1 with the mean value of 12.08 μSV y−1, which is lower than the safe limit 0.1 mSv y−1 as set by World Health Organization (WHO, 2004 and European Council (EU, 1998. Radon measurement in soil samples varies from 941 to 10,050 Bq m−3 with the mean value of 4561 Bq m−3, which lies within the range reported by other investigators. It was observed that the soil and water of Bikaner and Jhunjhunu districts are suitable for drinking and construction purpose without posing any health hazard.

  3. Responsibility and hand washing behaviour.

    Science.gov (United States)

    Taylor, Jasmine; Purdon, Christine

    2016-06-01

    Recent research suggests that compulsions persist due to a self-perpetuating mechanism of poor memory confidence and repetition. However, most of this work has examined checking compulsions and findings may not generalize well to washing compulsions. This study examined the role of responsibility in the persistence of washing behaviour. Hand washing was examined in undergraduates (n = 80) high and low in contamination fears (CF) under conditions of high or low responsibility (RL). Wash duration and number of visits to objects/locations key to the wash (e.g., soap) were examined. Overvalued responsibility predicted washing duration across groups. Neither wash duration nor number of visits was associated with memory for the wash. Wash duration predicted post-wash certainty that the wash had prevented harm, but only in the high CF group, and that effect varied according to RL: longer wash duration predicted greater certainty under conditions of low RL but predicted less certainty under conditions of high RL. Greater repetition predicted poorer sensory confidence, but only in the high CF group under high RL conditions. The data were collected in an analogue sample of modest size. Replication in a clinical sample is required. Self-perpetuating mechanisms identified in perseverative checking seem to also be present in perseverative washing, but only under conditions of high responsibility. Sensory confidence may be more important to perseverative washing than memory confidence. More research is required to understand self-perpetuating mechanisms at play when washing to under conditions of high responsibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Leaching of Fluoride from Biotite Mica in Soil: Implications for Fluoride in Shallow Groundwater

    OpenAIRE

    Kularatne, K. U. K. S.; Pitawala,H. M. T. G. A.

    2012-01-01

    Leaching of F − from biotite was investigated at room temperature by performing a series of short-term leach tests. The leaching of F − from biotite structure strongly depends on its weathering stage. Results of this study suggest that high concentration of F − is leached from highly weathered biotite, compared to fresh biotite. Results of dissolution experiments confirm that the organic acids in soil promote the leaching of F − from biotite compared to inorganic acids. Citric acid which is a...

  5. Processes affecting soil and groundwater contamination by DNAPL in low-permeability media

    Energy Technology Data Exchange (ETDEWEB)

    McWhorter, D.B. [Colorado State Univ., Fort Collins, CO (United States)

    1996-08-01

    This paper is one of a set of focus papers intended to document the current knowledge relevant to the contamination and remediation of soils and ground water by dense, nonaqueous phase liquids (DNAPL). The emphasis is on low permeability media such as fractured clay and till and unconsolidated, stratified formations. Basic concepts pertaining to immiscible-fluid mixtures are described and used to discuss such aspects as DNAPL transport, dissolved-phase transport, and equilibrium mass distributions. Several implications for remediation are presented. 27 refs., 8 figs., 4 tabs.

  6. Groundwater-soil moisture-climate interactions: lessons from idealized model experiments with forced water table depth

    Science.gov (United States)

    Ducharne, Agnès; Lo, Min-Hui; Decharme, Bertrand; Wang, Fuxing; Cheruy, Frédérique; Ghattas, Josefine; Chien, Rong-You; lan, Chia-Wei; Colin, Jeanne; Tyteca, Sophie

    2016-04-01

    Groundwater (GW) constitutes by far the largest volume of liquid freshwater on Earth. The most active part is soil moisture (SM), recognized as a key variable of land/atmosphere interactions, especially in so-called transition zones, where/when SM varies between wet and dry values. But GW can also be stored in deeper reservoirs than soils, in particular unconfined aquifer systems, in which the saturated part is called the water table (WT). The latter is characterized by slow and mostly horizontal water flows towards the river network, with well-known buffering effects on streamflow variability. Where/when the WT is shallow enough, it can also sustain SM by means of capillary rise, thus increase evapotranspiration (ET), with potential impact on the climate system (including temperatures and precipitation). The large residence time of GW may also increase the Earth system's memory, with consequences on the persistence of extreme events, hydro-climatic predictability, and anthropogenic climate change, particularly the magnitude of regional warming. Here, our main goal is to explore the potential impacts of the water table depth (WTD) on historical climate through idealized model analyses. To this end, we force three state-of-the art land surface models (LSMs), namely CLM, ORCHIDEE, and SURFEX, with prescribed WTDs ranging from 0.5 to 10 m. The LSMs are run either off-line or coupled to their parent climate model, following LMIP/AMIP-like protocols for intercomparability. Within this framework, we want to assess the sensitivity of ET and the simulated climate to the WTD in a systematic way. In particular, we will identify and compare the patterns of the critical WTD, defined as the deepest one to achieve a significant change in ET. To this end, we estimate derivatives of ET with respect to WTD, which tell how the sensitivity of ET to a unit change in WTD evolves with WTD. In each grid-point, these derivatives can be used to define the critical WTD, given a threshold ET

  7. Multi-bioindicators to assess soil microbial activity in the context of an artificial groundwater recharge with treated wastewater: a large-scale pilot experiment.

    Science.gov (United States)

    Michel, Caroline; Joulian, Catherine; Ollivier, Patrick; Nyteij, Audrey; Cote, Rémi; Surdyk, Nicolas; Hellal, Jennifer; Casanova, Joel; Besnard, Katia; Rampnoux, Nicolas; Garrido, Francis

    2014-06-28

    In the context of artificial groundwater recharge, a reactive soil column at pilot-scale (4.5 m depth and 3 m in diameter) fed by treated wastewater was designed to evaluate soil filtration ability. Here, as a part of this project, the impact of treated wastewater filtration on soil bacterial communities and the soil's biological ability for wastewater treatment as well as the relevance of the use of multi-bioindicators were studied as a function of depth and time. Biomass; bacterial 16S rRNA gene diversity fingerprints; potential nitrifying, denitrifying, and sulfate-reducing activities; and functional gene (amo, nir, nar, and dsr) detection were analyzed to highlight the real and potential microbial activity and diversity within the soil column. These bioindicators show that topsoil (0 to 20 cm depth) was the more active and the more impacted by treated wastewater filtration. Nitrification was the main activity in the pilot. No sulfate-reducing activity or dsr genes were detected during the first 6 months of wastewater application. Denitrification was also absent, but genes of denitrifying bacteria were detected, suggesting that the denitrifying process may occur rapidly if adequate chemical conditions are favored within the soil column. Results also underline that a dry period (20 days without any wastewater supply) significantly impacted soil bacterial diversity, leading to a decrease of enzyme activities and biomass. Finally, our work shows that treated wastewater filtration leads to a modification of the bacterial genetic and functional structures in topsoil.

  8. Evaluating the role of soil variability on groundwater pollution and recharge at regional scale by integrating a process-based vadose zone model in a stochastic approach

    Science.gov (United States)

    Coppola, Antonio; Comegna, Alessandro; Dragonetti, Giovanna; Lamaddalena, Nicola; Zdruli, Pandi

    2013-04-01

    Interpreting and predicting the evolution of water resources and soils at regional scale are continuing challenges for natural scientists. Examples include non-point source (NPS) pollution of soil and surface and subsurface water from agricultural chemicals and pathogens, as well as overexploitation of groundwater resources. The presence and build up of NPS pollutants may be harmful for both soil and groundwater resources. The accumulation of salts and trace elements in soils can significantly impact crop productivity, while loading of salts, nitrates, trace elements and pesticides into groundwater supplies can deteriorate a source of drinking and irrigation water. Consequently, predicting the spatial distribution and fate of NPS pollutants in soils at applicative scales is now considered crucial for maintaining the fragile balance between crop productivity and the negative environmental impacts of NPS pollutants, which is a basis of sustainable agriculture. Soil scientists and hydrologists are regularly asked to assist state agencies to understand these critical environmental issues. The most frequent inquiries are related to the development of mathematical models needed for analyzing the impacts of alternative land-use and best management use and management of soil and water resources. Different modelling solutions exist, mainly differing on the role of the vadose zone and its horizontal and vertical variability in the predictive models. The vadose zone (the region from the soil surface to the groundwater surface) is a complex physical, chemical and biological ecosystem that controls the passage of NPS pollutants from the soil surface where they have been deposited or accumulated due to agricultural activities, to groundwater. Physically based distributed hydrological models require the internal variability of the vadose zone be explored at a variety of scales. The equations describing fluxes and storage of water and solutes in the unsaturated zone used in these

  9. Experimental study on the vertical deformation of aquifer soils under conditions of withdrawing and recharging of groundwater in Tongchuan region, China

    Science.gov (United States)

    Wei, Ya-ni; Fan, Wen; Cao, Yanbo

    2017-03-01

    Land subsidence due to aquifer-system compaction accompanying groundwater extraction is a global hazard. Rising urban construction and groundwater demand necessitate increased awareness and better understanding of the geological problem. Motivated by the lack of laboratory-scale studies on this issue, an experimental investigation on the newly developed Tongchuan region, China, is presented. The study addresses the deformation behaviors of three soil samples, with the lithology of silty clay, silt, and fine sand, under the conditions of groundwater withdrawal and recharge using the GDS Consolidation Testing System. Results indicate that all three samples were characterized by elastic-plastic deformation under the conditions of withdrawing and recharging. The vertical deformation of the silty clay in the aquitard above the first confined aquifer was larger than those of the other two samples, and its deformation is a gradual and long process; thus, considerable attention should be paid to deformation in this aquitard due to the apparent creep effect and tiny rebound deformation. However, the settlement of the fine sand in the second confined aquifer cannot be ignored due to the great thickness of the aquifer. For the same soil, as the pore-water pressure declined, the unit rate of vertical deformation decreased gradually, whereas the creep effect of deformation in the later declining stage of pore-water pressure was more apparent than that in the former declining stage. These observations are highly important to the local government, which is developing measures to prevent and control subsidence.

  10. A simple daily soil-water balance model for estimating the spatial and temporal distribution of groundwater recharge in temperate humid areas

    Science.gov (United States)

    Dripps, W.R.; Bradbury, K.R.

    2007-01-01

    Quantifying the spatial and temporal distribution of natural groundwater recharge is usually a prerequisite for effective groundwater modeling and management. As flow models become increasingly utilized for management decisions, there is an increased need for simple, practical methods to delineate recharge zones and quantify recharge rates. Existing models for estimating recharge distributions are data intensive, require extensive parameterization, and take a significant investment of time in order to establish. The Wisconsin Geological and Natural History Survey (WGNHS) has developed a simple daily soil-water balance (SWB) model that uses readily available soil, land cover, topographic, and climatic data in conjunction with a geographic information system (GIS) to estimate the temporal and spatial distribution of groundwater recharge at the watershed scale for temperate humid areas. To demonstrate the methodology and the applicability and performance of the model, two case studies are presented: one for the forested Trout Lake watershed of north central Wisconsin, USA and the other for the urban-agricultural Pheasant Branch Creek watershed of south central Wisconsin, USA. Overall, the SWB model performs well and presents modelers and planners with a practical tool for providing recharge estimates for modeling and water resource planning purposes in humid areas. ?? Springer-Verlag 2007.

  11. Geochemical effects on the behavior of LLW radionuclides in soil/groundwater environments

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, K.M.; Sterne, R.J. [Pacific Northwest Lab., Richland, WA (United States)

    1995-12-31

    Assessing the migration potential of radionuclides leached from low-level radioactive waste (LLW) and decommissioning sites necessitates information on the effects of sorption and precipitation on the concentrations of dissolved radionuclides. Such an assessment requires that the geochemical processes of aqueous speciation, complexation, oxidation/reduction, and ion exchange be taken into account. The Pacific Northwest National Laboratory (PNNL) is providing technical support to the U.S. Nuclear Regulatory Commission (NRC) for defining the solubility and sorption behavior of radionuclides in soil/ground-water environments associated with engineered cementitious LLW disposal systems and decommissioning sites. Geochemical modeling is being used to predict solubility limits for radionuclides under geochemical conditions associated with these environments. The solubility limits are being used as maximum concentration limits in performance assessment calculations describing the release of contaminants from waste sources. Available data were compiled regarding the sorption potential of radionuclides onto {open_quotes}fresh{close_quotes} cement/concrete where the expected pH of the cement pore waters will equal to or exceed 10. Based on information gleaned from the literature, a list of preferred minimum distribution coefficients (Kd`s) was developed for these radionuclides. The K{sub d} values are specific to the chemical environments associated with the evolution of the compositions of cement/concrete pore waters.

  12. Washing technology development for gravel contaminated with uranium

    Energy Technology Data Exchange (ETDEWEB)

    Park, Uk Ryang; Kim, Gye Nam; Kim, Seung Soo; Kim, Wan Suk; Moon, Jai Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The soil washing method has a short decontamination time and is economical. In addition, methods including phytoremediation, solidification/stabilization and bioremediation exist. Phytoremediation and bioremediation are economical, but have low remedial efficiency. In addition, bioremediation causes washing wastewater because it requires a washing process for the separation of microorganisms from the soils. In addition, solidification/stabilization is a commonly used methods, but eventually increases the volume of wastes. As mentioned above, many researches involved in the decontamination of radioactively contaminated soils have been actively processed. On the other hand, researches for decontaminating radioactively contaminated gravels are not being currently processed. In this study, we performed basic experiments using decontamination methods to decontaminate radioactively contaminated gravel. First, we measured the concentration of uranium in gravel included in uranium-contaminated soils and performed a washing experiment to monitor the tendency of uranium removal. In addition, when managing gravel with a low uranium-decontamination rate, we tried to satisfy the radioactivity concentration criteria for self-disposal in the wastes (0.4Bq/g or less) by performing a washing experiment after only a physical crushing process. We performed washing experiments to satisfy the radioactivity concentration criteria for self-disposal (0.4 Bq/g or less) in gravel included in radioactively contaminated soil. We performed washing experiments for gravel whose initial average concentration of uranium was 1.3Bq/g. In addition, the average concentration of uranium was 0.8Bq/g. Too increase the decontamination rate, we crushed the gravel with a jaw crusher and performed the washing experiments. The results were similar to the results without crushing. In addition, it was determined that the smaller the size of the gravel particles, the more efficient the uranium decontamination

  13. Coupling ANIMO and MT3DMS for 3D regional-scale modeling of nutrient transport in soil and groundwater

    NARCIS (Netherlands)

    Jansen, Gijs M.C.; Del Val Alonso, Laura; Griffioen, Jasper; Groenendijk, P.

    2012-01-01

    We developed an on-line coupling between the 1D/quasi-2D nutrient transport model ANIMO and the 3D groundwater transport model code MT3DMS. ANIMO is a detailed, process-oriented simulation model code for the simulation of nitrate leaching to groundwater, N- and P-loads on surface waters and emission

  14. Removal Methods of Benzotriazole from Groundwater-Soil System%地下水-土系统中苯并三唑去除方法研究

    Institute of Scientific and Technical Information of China (English)

    邢辰; 梁静

    2012-01-01

    含苯并三唑的地下水很难用常规的水污染处理方法去除,因此迫切需要探讨它在地下水-土系统中有效的去除方法.详细介绍了吸附法、光激发氧化法和生物法,并且针对这些方法应用到地下水中的可行性进行了分析.结果表明,吸附法受到环境因素的限制,并会发生缓慢的解析过程,需进一步探索和完善;光激发氧化法去除效果较好但仍处于探索阶段,需改善耗费较多人力、物力、财力的缺点.目前的生物法很难对苯并三唑进行降解,尚需要进一步的研究.%It was difficult to remove benzotriazole (BTA) in groundwater with conventional water treatment methods. Therefore, there is an urgent need to assess the effective removal methods in groundwater-soil system. The adsorption methods, UV-O3 methods and biological methods were introduced in this article. The feasibility of applying these methods in groundwater was discussed. The results indicated that the adsorption method is limited by environmental factors and needs to be improved for real application. The removal effect of BTA by UV-03 method is good, however, its application is still in the preliminary stage. The UV-03 technology needs more manpower, material and financial resources. More works need to be carried out in the biological removal of BTA in groundwater-soil system.

  15. Geo-Accumulation Indices of Heavy Metals in Soil and Groundwater of Kanpur, India Under Long Term Irrigation of Tannery Effluent.

    Science.gov (United States)

    Dotaniya, M L; Meena, V D; Rajendiran, S; Coumar, M Vassanda; Saha, J K; Kundu, S; Patra, A K

    2016-11-22

    Soil and groundwater from long-term (>50 years) tannery effluent irrigated areas of Kanpur were analyzed and significant buildup of heavy metals such as Cr, Ni, Cd, Pb, Zn, and As in the range of 252-972, 23-30, 2.3-14.1, 23.7-58.8, 138-338 and 6.8-11 mg kg(-1), respectively in soil was found. Few groundwater samples in the effluent irrigated areas also exhibited high Cr concentration above the permissible limit of United States Environmental Protection Agency. The tannery effluents contained 1.53-57.3 ppm Cr, 0-0.12 ppm Ni, 0-0.02 ppm Cd, 0-0.07 ppm Pb, 0-0.48 ppm Zn and 0-0.03 ppm As. The Geo-accumulation index (Igeo) revealed that soil samples were unpolluted to moderately polluted with Cu, Ni, Zn, Pb and As; moderately polluted in case of Cd; and heavily to extremely polluted by Cr.

  16. Lead isotopes in soils and groundwaters as tracers of the impact of human activities on the surface environment: The Domizio-Flegreo Littoral (Italy) case study

    Science.gov (United States)

    Grezzi, G.; Ayuso, R.A.; de Vivo, B.; Lima, A.; Albanese, S.

    2011-01-01

    The isotopic signature of geogenic and anthropogenic materials, in combination with concentration data for pollutants, can help trace the origin and the extent of contamination in the environment. This approach is particularly effective if naturally occurring and anthropogenically introduced metals have different isotopic ratios. Lead isotope analysis on soils from 7 profiles (1. m depth) and on groundwaters from 8 wells have been used to determine the impact of human activities on the surface environment of Domizio-Flegreo Littoral. Result obtained show that in sub-rural areas the isotopic composition of the samples collected along the soil profiles of Domizio-Flegreo Littoral is likely mostly controlled by the nature of the parent geologic material (natural) while in more urbanized areas (Giugliano) Pb isotopic composition in superficial soils is mostly influenced by anthropic sources such as motor vehicles. Lead isotopic ratios in groundwaters also show that the use of pesticides and, probably, the influence of aerosols and the presence of illegal waste disposal can influence water quality. ?? 2010 Elsevier B.V.

  17. Instrumenting an upland research catchment in Canterbury, New Zealand to study controls on variability of soil moisture, shallow groundwater and streamflow

    Science.gov (United States)

    McMillan, Hilary; Srinivasan, Ms

    2015-04-01

    Hydrologists recognise the importance of vertical drainage and deep flow paths in runoff generation, even in headwater catchments. Both soil and groundwater stores are highly variable over multiple scales, and the distribution of water has a strong control on flow rates and timing. In this study, we instrumented an upland headwater catchment in New Zealand to measure the temporal and spatial variation in unsaturated and saturated-zone responses. In NZ, upland catchments are the source of much of the water used in lowland agriculture, but the hydrology of such catchments and their role in water partitioning, storage and transport is poorly understood. The study area is the Langs Gully catchment in the North Branch of the Waipara River, Canterbury: this catchment was chosen to be representative of the foothills environment, with lightly managed dryland pasture and native Matagouri shrub vegetation cover. Over a period of 16 months we measured continuous soil moisture at 32 locations and near-surface water table (account for aspect, but our results suggest that it is an important factor in hillslope runoff generation. Co-measurement of soil moisture and water table level allowed us to identify interrelationships between the two. Locations where water tables peaked closest to the surface had consistently wetter soils and higher water tables. These wetter sites were the same across seasons. However, temporary patterns of strong soil moisture response to summer storms did not correspond to the wetter sites. Total catchment spatial variability is composed of multiple variability sources, and the dominant type is sensitive to those stores that are close to a threshold such as field capacity or saturation. Therefore, we classified spatial variability as 'summer mode' or 'winter mode'. In summer mode, variability is controlled by shallow processes e.g. interactions of water with soils and vegetation. In winter mode, variability is controlled by deeper processes e

  18. The Effects of Removal of Heavy Metal and Changes of Basic Properties on Contaminated Soils by Composite Washing with Organic Acids and Chlorides%有机酸-氯化物复合浸提去除土壤重金属的效应及对土壤理化性质的影响

    Institute of Scientific and Technical Information of China (English)

    曾嘉强; 吴文成; 戴军; 董长勋

    2015-01-01

    化学淋洗作为一种高效、能彻底去除土壤重金属污染的修复技术而受到广泛关注,其中淋洗剂的选择是淋洗技术的关键,另外淋洗修复后土壤性质的变化一直是限制淋洗技术推广应用的因素之一。以某冶炼厂周边重金属Cd、Pb污染农田土壤为研究对象,采用振荡浸提方法,研究了有机酸(柠檬酸、酒石酸、苹果酸、乙酸和草酸)与氯化物(FeCl3、CaCl2、MgCl2、KCl和NaCl)单独浸提,以及有机酸与氯化物复合浸提对土壤中Cd、Pb的去除效果,并测定了浸提前后土壤理化性质的变化。结果表明,有机酸对土壤中Cd、Pb的去除效率大小顺序为柠檬酸>苹果酸(酒石酸)>草酸>乙酸;氯化物大小顺序为FeCl3>CaCl2>MgCl2>KCl>NaCl。柠檬酸(150 mmol·L-1)和FeCl3(50 mmol·L-1)复合浸提,对Cd、Pb的去除率显著提高,对于老王寨土样,分别达到44.6%和29.0%,而柠檬酸和FeCl3单独浸提分别为36.4%和15.1%、28.0%和10.9%;对于大田湾土样,对Cd、Pb的去除率分别达到64.4%和16.9%,而柠檬酸单独浸提为445.4%和10.8%,FeCl3单独浸提Cd只有5.0%,Pb几乎未洗出。柠檬酸(100 mmol·L-1)与FeCl3(50 mmol·L-1)复合连续浸提3次后,老王寨和大田湾土样土壤pH值下降显著,分别下降2.45和4.03个单位;CEC和速效N、P、K含量下降显著,游离氧化铝显著增加,有机质变化不显著。淋洗修复后的农田土壤重金属含量大幅降低,为后续实施植物修复等技术降低压力和风险,后续耕作,建议施加碱石灰调节土壤pH,并补充N、P、K肥料。%Chemical washing technique has been one of the hot soil remediations because of its high efficiency and complete removal of the heavy metals in soils. The key of washing technique is washing agents, furthermore, the changes of the soil basic properties after washing has been one of the factors that limited to

  19. DETAILED ANALYSIS OF THE MOST PROMISING ALTERNATIVES TO USING GRANULAR ACTIVATED CARBON TO TREAT 200-ZP-1 GROUNDWATER AND 200-PW-1 SOIL VAPOR

    Energy Technology Data Exchange (ETDEWEB)

    BYRNES ME, KALMAR JA

    2007-11-26

    This document presents a detailed evaluation of selected alternative treatment options to granular activated carbon (GAC) for removing carbon tetrachloride generated from the groundwater pump-and-treat system at the 200-ZP-I Operable Unit (OU) in the 200 West Area of the Hanford Site. This evaluation of alternative treatment options to GAC is also applicable to the vadose zone soil vapor extraction (SVE) system at the 200-PW-l OU, which is also located in the Hanford Site's 200 West Area.

  20. Measured and simulated effects of sophisticated drainage techniques on groundwater level and runoff hydrochemistry in areas of boreal acid sulphate soils

    Directory of Open Access Journals (Sweden)

    I. BÄRLUND

    2008-12-01

    Full Text Available To abate the environmental problems caused by the severe acidity and high metal concentrations in rivers draining acid sulphate (AS soils of Western Finland, control drainage (CD and lime filter drainage (LFD, and their combination, were investigated. The effectiveness of these best management practices (BMP’s on drainage water quality was studied on plot scale in two locations. In Ilmajoki, where the sulphidic materials are more than 2 m below the soil surface, CD efficiently reduced the concentrations of sulphate, aluminium, manganese and iron concentrations and to some extent also increased the pH of the drainage waters. LFD, in contrast, effectively reduced the drainage water acidity and raised the pH level. Decrease of the groundwater level owing to strong evapotranspiration in summer could, however, not be properly prevented by CD. In Mustasaari where sulphidic materials were as shallow as 1 m below soil surface, the positive effects of LFD recognised in Ilmajoki were hardly seen. This shows, that the tested BMP’s work properly, and can thus be recommended, for intensively artificially drained AS soils like in Ilmajoki where most of the acidity has already been transported to watercourses. LFD can, however, not be recommended for as yet poorly leached and thus particularly problematic AS soils like in Mustasaari. This is, of course, a drawback of the tested BMP, as it is not effective for the soils which would need it most. The field data were tentatively utilised to test the performance of the HAPSU (Ionic Flow Model for Acid Sulphate Soils simulation model developed to estimate the loads of harmful substances from AS soils.;

  1. Remediation of Soil Co-contaminated with Heavy Metals by Washing with Citric Acid:Batch Experiment and Extraction Mechanism%柠檬酸对重金属复合污染土壤的淋洗修复效果与机理

    Institute of Scientific and Technical Information of China (English)

    李玉双; 胡晓钧; 宋雪英; 侯永侠; 陈红亮; 杨继松

    2012-01-01

    土壤淋洗修复是永久性的污染土壤修复方法之一.以Cd、Cu、Pb复合污染土壤为研究对象,采用振荡淋洗法结合形态分析技术研究了柠檬酸对重金属复合污染土壤的淋洗修复效果及其去除机理.结果表明,柠檬酸对复合污染土壤中的Cd和Cu具有较好的洗脱效果,而Pb的淋洗去除率相对较低.80mmol.L-1的柠檬酸对Cd、Cu、Pb的去除率分别能够达到90.4%、82.5%和38.6%.柠檬酸淋洗去除的重金属在土壤中主要以可交换态、碳酸盐结合态和铁锰氧化物结合态的形式存在.%Soil washing is one of the few permanent treatment alternatives to remove contaminants from soils. Batch experiment was conducted to evaluate the performance of potential capability of citric acid to washing co-contaminated soil with Cd,Cu and Pb. The fraction and distribution of heavy metals in soil were evaluated using the sequential extraction technique to discuss the mechanism of citric acid extraction. Results show that citric acid could effectively remove Cd and Cu from co- contaminated soil, but relatively low removal rate of Pb. The removal of Cd, Cu, and Pb is respectively 90.4%, 82.5%, and 38.6% washing with 80 mmol ·L-1 citric acid solution. The removed heavy metals by citric acid are mainly from the exchangeable, carbonate bound and Fe-Mn oxide fractions.

  2. Bacterial Exchange in Household Washing Machines

    Science.gov (United States)

    Callewaert, Chris; Van Nevel, Sam; Kerckhof, Frederiek-Maarten; Granitsiotis, Michael S.; Boon, Nico

    2015-01-01

    Household washing machines (WMs) launder soiled clothes and textiles, but do not sterilize them. We investigated the microbial exchange occurring in five household WMs. Samples from a new cotton T-shirt were laundered together with a normal laundry load. Analyses were performed on the influent water and the ingoing cotton samples, as well as the greywater and the washed cotton samples. The number of living bacteria was generally not lower in the WM effluent water as compared to the influent water. The laundering process caused a microbial exchange of influent water bacteria, skin-, and clothes-related bacteria and biofilm-related bacteria in the WM. A variety of biofilm-producing bacteria were enriched in the effluent after laundering, although their presence in the cotton sample was low. Nearly all bacterial genera detected on the initial cotton sample were still present in the washed cotton samples. A selection for typical skin- and clothes-related microbial species occurred in the cotton samples after laundering. Accordingly, malodour-causing microbial species might be further distributed to other clothes. The bacteria on the ingoing textiles contributed for a large part to the microbiome found in the textiles after laundering. PMID:26696989

  3. When does the fluazifop-P-butyl degradate, TFMP, leach through an agricultural loamy soil to groundwater?

    DEFF Research Database (Denmark)

    Vendelboe, Anders Lindblad; Norgaard, Trine; Olsen, Preben

    2016-01-01

    In intensely cultivated regions, it is crucial to have knowledge of the leaching potential related to pesticides in agricultural production. This is especially true in countries, like Denmark, that base its drinking water supply on untreated groundwater. Since fluazifop-P-butyl (FPB) is applied...... value for drinking water applies to them, having its leaching potential regulatory assessed based on high quality estimations of their persistence, and be exposed to an assessment of the risk to consumers of drinking contaminated groundwater....

  4. Summary of inorganic compositional data for groundwater, soil-water, and surface-water samples collected at the Headgate Draw subsurface drip irrigation site, Johnson County, Wyoming

    Science.gov (United States)

    Geboy, Nicholas J.; Engle, Mark A.; Schroeder, Karl T.; Zupancic, John W.

    2011-01-01

    As part of a 5-year project on the impact of subsurface drip irrigation (SDI) application of coalbed-methane (CBM) produced waters, water samples were collected from the Headgate Draw SDI site in the Powder River Basin, Wyoming, USA. This research is part of a larger study to understand short- and long-term impacts on both soil and water quality from the beneficial use of CBM waters to grow forage crops through use of SDI. This document provides a summary of the context, sampling methodology, and quality assurance and quality control documentation of samples collected prior to and over the first year of SDI operation at the site (May 2008-October 2009). This report contains an associated database containing inorganic compositional data, water-quality criteria parameters, and calculated geochemical parameters for samples of groundwater, soil water, surface water, treated CBM waters, and as-received CBM waters collected at the Headgate Draw SDI site.

  5. Summary of Inorganic Compositional Data for Groundwater, Soil-Water, and Surface-Water Samples at the Headgate Draw Subsurface Drip Irrigation Site

    Energy Technology Data Exchange (ETDEWEB)

    Geboy, Nicholas J.; Engle, Mark A.; Schroeder, Karl T.; Zupanic, John W.

    2007-01-01

    As part of a 5-year project on the impact of subsurface drip irrigation (SDI) application of coalbed-methane (CBM) produced waters, water samples were collected from the Headgate Draw SDI site in the Powder River Basin, Wyoming, USA. This research is part of a larger study to understand short- and long-term impacts on both soil and water quality from the beneficial use of CBM waters to grow forage crops through use of SDI. This document provides a summary of the context, sampling methodology, and quality assurance and quality control documentation of samples collected prior to and over the first year of SDI operation at the site (May 2008-October 2009). This report contains an associated database containing inorganic compositional data, water-quality criteria parameters, and calculated geochemical parameters for samples of groundwater, soil water, surface water, treated CBM waters, and as-received CBM waters collected at the Headgate Draw SDI site.

  6. 不同地下水埋深污灌硝态氮对土壤-地下水环境影响试验研究%Research on nitrate to negative effect of soil and groundwater environment at different groundwater depth with sewage irrigation

    Institute of Scientific and Technical Information of China (English)

    刘伟佳; 吴军虎; 彭忠福

    2012-01-01

    Groundwater depth is one of main factors affecting the migration of sewage irrigation pollutants in soil and groundwater system.This paper analyzed the transportation characteristic of nitrate in soil and groundwater under different groundwater depth through laboratory experiments with sewage irrigation.The results indicated that the effects of different groundwater depth on soil and groundwater environment,including the distribution of soil water and migration path of nitrate,were significant.Under the lower groundwater depth,although the higher soil moisture potential energy and denitrification restrict the migration tendency of nitrate in sewage from up to down,the higher soil moisture potential energy and shorter migration path make it easy for the nitrate of soil matrix to be pushed from subsoil to groundwater,then the pollution risk of groundwater increased.%地下水埋深是影响污灌污染物在土壤-地下水系统中运移特性的主要因素之一。通过室内污水入渗试验,研究了不同地下水埋深条件下污灌污染物NO3--N在土壤中的运移特性及对地下水环境的影响。研究结果表明:地下水埋深的不同导致了土壤内水分分布和NO3--N迁移路径的差异,从而影响了NO3--N在土壤-地下水系统中的运移特性。埋深浅,高土水势能和反硝化潜势制约了污水携带NO3--N向下层土壤迁移淋失的趋势,但高土水势能和短迁移路径使下层土壤基质中的NO3--N易被挤入至地下水中,NO3--N污染地下水风险较大。

  7. Perfluorinated compounds (PFCs) in groundwater and aqueous soil extracts: using inline SPE-LC-MS/MS for screening and sorption characterisation of perfluorooctane sulphonate and related compounds

    Energy Technology Data Exchange (ETDEWEB)

    Enevoldsen, Rasmus [Geological Survey of Denmark and Greenland (GEUS), Department of Geochemistry, Copenhagen (Denmark); Novo Nordisk A/S, Kalundborg (Denmark); Juhler, Rene K. [Geological Survey of Denmark and Greenland (GEUS), Department of Geochemistry, Copenhagen (Denmark)

    2010-10-15

    Perfluorinated compounds (PFCs) have been recognised as emerging pollutants of global relevance. A fully automated method with inline solid-phase extraction coupled to electrospray ionisation liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS) is presented and used for characterisation of soil adsorption and desorption for six PFCs: perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorobutane sulphonate (PFBS), and perfluorooctane sulphonate (PFOS). The method reduces sample turnaround time and solvent consumption and is suitable for low volume sampling. The only sample preparation necessary for water samples was sedimentation by centrifugation. The method has a total runtime of 21 min including inline sample cleanup (2 min for injection and SPE, 14 min for the chromatographic separation, 5 min for reconditioning). Negative AP-ESI with selective reaction monitoring (SRM) was used and the method was documented for quantification of the six environmentally important PFCs in subsoil matrix and related aqueous matrixes (groundwater and drainage water). Linearity was demonstrated in the range 5 to 2,500 ng/l and the LOD was between 2 and 8 ng/l in groundwater. Adsorption was characterised by linear Freundlich isotherms for all six compounds in two agricultural top soils (A horizon, sandy and clayey soil).Variability in sorption characteristics for soil types as well as compound properties were found, and correlation between the organic carbon normalised sorption coefficient (K{sub OC}) and PFC molecular weight was demonstrated. The K{sub d} values were in the range 0.1 to 33 (l/kg), and 0.3 to 65 (l/kg) for sorption and desorption respectively. (orig.)

  8. Toxic elements in soil and groundwater: short-time study on electrokinetic removal of arsenic in the presence of other ions.

    Science.gov (United States)

    Leszczynska, Danuta; Ahmad, Hafiz

    2006-06-01

    The electrokinetic technique is an emerging technology presently tested in situ to remove dissolved heavy metals from contaminated groundwater. There is a growing interest for using this system to cleanse clayey soil contaminated by toxic metallic ions. Currently, there are very few available non-destructive treatment methods that could be successfully applied in situ on low permeable type of soil matrix. The main objective of presented study was to validate and possibly enhance the overall efficiency of decontamination by the electrokinetic technique of the low permeable soil polluted by the arsenic in combination with chromium and copper ions. The chosen mixture of ions was imitating leak of pesticide well known as chromate copper arsenate (CCA). The chosen technique is showing a big promise to be used in the future as a portable, easy to install and run on sites with spills or leaks hard to reach otherwise; such as in the dense populated and urbanized areas. Laboratory electrokinetic experiments were designed to understand and possibly manipulate main mechanisms involved during forced migration of ions. All tests were conducted on artificially contaminated kaolinite (low permeable clay soil). Electrokinetic migration was inducted by the low voltage dc current applied through soil column. Series of experiments were designed to assess the efficiency of arsenic-chromium-copper remediation by applying (1) only dc current; and (2) by altering the soil environment. Obtained results showed that arsenic could be successfully removed from the soil in one day (25 hours) span. It was significant time reduction, very important during emergency response. Mass recovered at the end of each test depended on initial condition of soil and type of flushing solution. The best results were obtained, when soil was flushed with either NaOH or NaOCl (total removal efficiency 74.4% and 78.1%, respectively). Direct analysis of remained arsenic in soil after these tests confirmed

  9. Toxic Elements in Soil and Groundwater: Short-Time Study on Electrokinetic Removal of Arsenic in the Presence of other Ions

    Directory of Open Access Journals (Sweden)

    Hafiz Ahmad

    2006-06-01

    Full Text Available The electrokinetic technique is an emerging technology presently tested in situ to remove dissolved heavy metals from contaminated groundwater. There is a growing interest for using this system to cleanse clayey soil contaminated by toxic metallic ions. Currently, there are very few available non-destructive treatment methods that could be successfully applied in situ on low permeable type of soil matrix. The main objective of presented study was to validate and possibly enhance the overall efficiency of decontamination by the electrokinetic technique of the low permeable soil polluted by the arsenic in combination with chromium and copper ions. The chosen mixture of ions was imitating leak of pesticide well known as chromate copper arsenate (CCA. The chosen technique is showing a big promise to be used in the future as a portable, easy to install and run on sites with spills or leaks hard to reach otherwise; such as in the dense populated and urbanized areas. Laboratory electrokinetic experiments were designed to understand and possibly manipulate main mechanisms involved during forced migration of ions. All tests were conducted on artificially contaminated kaolinite (low permeable clay soil. Electrokinetic migration was inducted by the low voltage dc current applied through soil column. Series of experiments were designed to assess the efficiency of arsenic-chromium-copper remediation by applying (1 only dc current; and (2 by altering the soil environment. Obtained results showed that arsenic could be successfully removed from the soil in one day (25 hours span. It was significant time reduction, very important during emergency response. Mass recovered at the end of each test depended on initial condition of soil and type of flushing solution. The best results were obtained, when soil was flushed with either NaOH or NaOCl (total removal efficiency 74.4% and 78.1%, respectively. Direct analysis of remained arsenic in soil after these tests

  10. 不同潜水埋深下土壤水盐运移特征及其交互效应%Migration characteristics of soil water and salt and their interaction under different groundwater levels

    Institute of Scientific and Technical Information of China (English)

    夏江宝; 赵西梅; 赵自国; 陈印平; 刘俊华

    2015-01-01

    为探讨盐水矿化度下土壤水盐分布特征对潜水埋深的响应规律及其水盐交互效应,以黄河三角洲建群种柽柳(Tamarix chinensis Lour)栽植的土壤柱体为研究对象,模拟设置0.3、0.6、0.9、1.2、1.5和1.8 m共6种潜水水位,测定分析各水位处理下不同土壤剖面的相对含水率、含盐量及土壤溶液绝对浓度等水盐参数。结果表明:随潜水水位的增加,整个土柱水分均值显著降低,土壤含盐量和溶液绝对浓度均值先升高后降低,1.2 m水位是土壤水盐变化的转折点,此水位下各土壤剖面的含盐量和土壤溶液绝对浓度均达最高。土柱水分和盐分变化幅度最大的水位分别在中水位0.9~1.2 m,浅水位0.6 m,土壤溶液绝对浓度变化最剧烈的是深水位1.5~1.8 m。随土壤深度的增加,土壤水分显著升高,土壤盐分先降低后升高,表土层盐分均值最高达1.36%,但土壤溶液绝对浓度显著减小。土壤含盐量、土壤相对含水率与潜水水位分别呈极显著(P<0.01)和显著(P<0.05)负相关,土壤相对含水率与盐分呈极显著正相关(P<0.01)。地下盐水矿化度下,柽柳幼苗栽植深度应超过20 cm深,适宜潜水水位在1.5~1.8 m,栽植深度以30~40 cm较好。研究结果可为地下盐水作用条件下土壤次生盐渍化的防治和柽柳栽植管理提供参考。%Soil salt and water closely related to groundwater depth mainly affect vegetation distribution pattern and community succession of the Yellow River Delta. Thus,it is important to explain the changing process of water and salt in groundwater and soil and their effects on the occurrence of the secondary salinization. This study aimed to understand the response of soil water-salt distribution characteristics to groundwater depth and their interactive effects under saline groundwater conditions. To achieve the objective, a laboratory experiment was

  11. High-resolution monitoring across the soil-groundwater interface - Revealing small-scale hydrochemical patterns with a novel multi-level well

    Science.gov (United States)

    Gassen, Niklas; Griebler, Christian; Stumpp, Christine

    2016-04-01

    Biogeochemical turnover processes in the subsurface are highly variable both in time and space. In order to capture this variability, high resolution monitoring systems are required. Particular in riparian zones the understanding of small-scale biogeochemical processes is of interest, as they are regarded as important buffer zones for nutrients and contaminants with high turnover rates. To date, riparian research has focused on influences of groundwater-surface water interactions on element cycling, but little is known about processes occurring at the interface between the saturated and the unsaturated zone during dynamic flow conditions. Therefore, we developed a new type of high resolution multi-level well (HR-MLW) that has been installed in the riparian zone of the Selke river. This HR-MLW for the first time enables to derive water samples both from the unsaturated and the saturated zone across one vertical profile with a spatial vertical resolution of 0.05 to 0.5 m to a depth of 4 m b.l.s. Water samples from the unsaturated zone are extracted via suction cup sampling. Samples from the saturated zone are withdrawn through glass filters and steel capillaries. Both, ceramic cups and glass filters, are installed along a 1" HDPE piezometer tube. First high resolution hydrochemical profiles revealed a distinct depth-zonation in the riparian alluvial aquifer. A shallow zone beneath the water table carried a signature isotopically and hydrochemically similar to the nearby river, while layers below 1.5 m were influenced by regional groundwater. This zonation showed temporal dynamics related to groundwater table fluctuations and microbial turnover processes. The HR-MLW delivered new insight into mixing and turnover processes between riverwater and groundwater in riparian zones, both in a temporal and spatial dimension. With these new insights, we are able to improve our understanding of dynamic turnover processes at the soil - groundwater interface and of surface

  12. Technical assistance to Ohio closure sites; Recommendations toaddress contaminated soils, concrete, and corrective action managementunit/groundwater contamination at Ashtabula, Ohio

    Energy Technology Data Exchange (ETDEWEB)

    Charoglu, Emily; Eddy-Dilek, Carol; Gombert, Dirk; Hazen, Terry; Johnson, Bob; Looney, Brian; Krstich, Michael A.; Rautman, Chris; Tripp,Julia; Whitmill, Larry

    2002-08-26

    The Ashtabula Environmental Management Project (AEMP) at Department of Energy-Ohio (DOE-OH) requested technical assistance from the EM-50 Lead Lab to aid in defining new cost and time effective approaches in the following problem areas: soils, concrete, and groundwater/Corrective Action Management Unit (CAMU) at RMIES in Ashtabula, Ohio. Attachment 1 provides the site request for assistance. The technical assistance team assembled for this request is provided in Attachment 2. These individuals reviewed key site information prior to convening with DOE and contractor personnel (RMIES and Earthline) for a three-and-a-half-day meeting to better understand baseline technologies, limitations, and site-specific issues. After listening to presentations about the nature and extent of known contamination, the team broke out into several groups to brainstorm ideas and develop viable solutions. This executive summary details unresolved issues requiring management attention as well as recommendations to address soils, concrete, and groundwater/CAMU. It also provides a summary of additional technical assistance that could be provided to the site. More details are presented in the body of this report.

  13. Integrating soil water and tracer balances, numerical modelling and GIS tools to estimate regional groundwater recharge: Application to the Alcadozo Aquifer System (SE Spain).

    Science.gov (United States)

    Hornero, Jorge; Manzano, Marisol; Ortega, Lucía; Custodio, Emilio

    2016-10-15

    Groundwater recharge is one of the key variables for aquifer management and also one of the most difficult to be evaluated with acceptable accuracy. This is especially relevant in semiarid areas, where the processes involved in recharge are widely variable. Uncertainty should be estimated to know how reliable recharge estimations are. Groundwater recharge has been calculated in the Alcadozo Aquifer System, under steady state conditions, at regional (aquifer) and sub-regional (spring catchment) scales applying different methods. The regional distribution of long-term average recharge values has been estimated with the chloride mass balance method using data from four rain stations and 40 groundwater samples covering almost the whole aquifer surface. A remarkable spatial variability has been found. Average annual recharge rates ranges from 20 to 243mmyear(-1) across the aquifer, with an estimated coefficient of variation between 0.16 and 0.38. The average recharge/precipitation ratio decreases from 34% in the NW to 6% in the SE, following the topographic slope. At spring-catchment scale, recharge has been estimated by modelling the soil water balance with the code Visual Balan 2.0. The results, calibrated with discharge data of the two main springs Liétor and Ayna, are 35.5 and 50mmyear(-1) respectively, with estimated coefficients of variation of 0.49 and 0.36. A sensitivity analysis showed that soil parameters influence the most the uncertainty of recharge estimations. Recharge values estimated with both methods and at two temporal and spatial scales are consistent, considering the regional variability obtained with the chloride method and the respective confidence intervals. Evaluating the uncertainties of each method eased to compare their relative results and to check their agreement, which provided confidence to the values obtained. Thus, the use of independent methods together with their uncertainties is strongly recommended to constrain the magnitude and to

  14. Soil- and groundwater-quality data for petroleum hydrocarbon compounds within Fuels Area C, Ellsworth Air Force Base, South Dakota, 2014

    Science.gov (United States)

    Bender, David A.; Rowe, Barbara L.

    2015-01-01

    Ellsworth Air Force Base is an Air Combat Command located approximately 10 miles northeast of Rapid City, South Dakota. Ellsworth Air Force Base occupies about 6,000 acres within Meade and Pennington Counties, and includes runways, airfield operations, industrial areas, housing, and recreational facilities. Fuels Area C within Ellsworth Air Force Base is a fuels storage area that is used to support the mission of the base. In fall of 2013, the U.S. Geological Survey began a study in cooperation with the U.S. Air Force, Ellsworth Air Force Base, to estimate groundwater-flow direction, select locations for permanent monitoring wells, and install and sample monitoring wells for petroleum hydrocarbon compounds within Fuels Area C. Nine monitoring wells were installed for the study within Fuels Area C during November 4–7, 2014. Soil core samples were collected during installation of eight of the monitoring wells and analyzed for benzene, toluene, ethylbenzene, total xylenes, naphthalene,m- and p-xylene, o-xylene, and gasoline- and diesel-range organic compounds. Groundwater samples were collected from seven of the nine wells (two of the monitoring wells did not contain enough water to sample or were dry) during November 19–21, 2014, and analyzed for select physical properties, benzene, toluene, ethylbenzene, total xylenes, naphthalene, m- and p-xylene, o-xylene, and gasoline- and diesel-range organic compounds. This report describes the nine monitoring well locations and presents the soil- and groundwater-quality data collected in 2014 for this study.

  15. Hydrochemical heterogeneity in an upland catchment: further characterisation of the spatial, temporal and depth variations in soils, streams and groundwaters of the Plynlimon forested catchment, Wales

    Directory of Open Access Journals (Sweden)

    P. Shand

    2005-01-01

    Full Text Available The heterogeneous nature of upland hard-rock catchments in terms of geology, geomorphology, superficial deposits, soil type and land use gives rise to a range of hydrochemical characteristics in stream waters. This is further complicated by the large and often rapid changes in stream flow typical of storm events. The sources of solutes and flow pathways in hard-rock catchments are still poorly understood, in particular the role of bedrock groundwater. Spatial variations in water chemistry are presented for stream waters, soils and groundwaters in the forested Plynlimon catchment of Wales, UK. The results highlight a large degree of spatial heterogeneity in each of these systems. This has major implications for the application of end-member mixing analysis and presents serious problems for modelling in scaling up from study sites to catchment scale. However, such data provide important constraints on sources, flow pathways and residence times within individual catchment compartments, knowledge of which is essential for understanding how such catchments function. The characterisation of sub-surface waters in upland catchments requires a great deal of care during sampling as well as high spatial and temporal resolution of sampling, and further work is required to characterise the Plynlimon catchments fully. Nevertheless, the presence of an active and highly stratified groundwater system is considered important as a source of solutes and water to streams. It also provides a storage medium that is likely to make a major contribution to explaining the strongly damped rainfall Cl and d2H signals measured in the streams.

  16. Measurement of dissolved Cs-137 in stream water, soil water and groundwater at Headwater Forested Catchment in Fukushima after Fukushima Dai-ichi Nuclear Power Plant Accident

    Science.gov (United States)

    Iwagami, Sho; Tsujimura, Maki; Onda, Yuichi; Sakakibara, Koichi; Konuma, Ryohei; Sato, Yutaro

    2016-04-01

    Radiocesium migration from headwater forested catchment is important perception as output from the forest which is also input to the subsequent various land use and downstream rivers after Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident. In this study, dissolved Cs-137 concentration of stream water, soil water and groundwater were measured. Observations were conducted at headwater catchment in Yamakiya district, located 35 km northwest of FDNPP from April 2014 to November 2015. Stream water discharge was monitored and stream water samples were taken at main channel and sub channel. Stream water discharge was monitored by combination of parshallflume and v-notch weir. Stream water was sampled manually at steady state condition in 3-4 month interval and also intense few hours interval sampling were conducted during rainfall events using automated water sampler. Around the sub channel, it is found that there is a regularly saturated area at the bottom of the slope, temporary saturated area which saturate during the rainy season in summer and regularly dry area. 6 interval cameras were installed to monitor the changing situation of saturated area. Suction lysimeters were installed at three areas (regularly saturated area, temporary saturated area and dry area) for sampling soil water in depth of 0.1 m and 0.3 m. Boreholes were installed at three points along the sub channel. Three boreholes with depth of 3 m, 5 m and 10 m were installed at temporary saturated area, 20 m upstream of sub channel weir. Another three boreholes with depth of 3 m, 5 m and 10 m were installed at dry area, 40 m upstream of sub channel weir. And a borehole with depth of 20 m was installed at ridge of sub catchment, 52 m upstream of sub channel weir. Groundwater was sampled by electrically powered pump and groundwater level was monitored. Also suction-free lysimeter was installed at temporary saturated area for sampling the near surface subsurface water. Soil water samples were collected

  17. Lead isotopic compositions of soil and near-surface till profiles from a watershed containing arsenic-enriched groundwater in coastal Maine

    Science.gov (United States)

    Ayuso, Robert; Foley, Nora; Wandless, Gregory; Dillingham, Jeremy; Colvin, Anna

    2005-01-01

    Lead isotope compositions of soils and near-surface tills from an area of coastal Maine known to have groundwater with anomalously high arsenic contents were measured in order to determine the source of the lead and, by inference, possible sources of arsenic. Five soil and till sites were selected for detailed chemical and isotopic analysis. To construct profiles of the soil and till horizons, five samples were collected at 10-cm intervals from the surface to the base of each horizon. Total lead and arsenic concentrations and lead isotopic compositions were measured for 48 leaches and bulk residues. The soils and tills are underlain by sulfidic schists of the Penobscot Formation. Several generations of minerals containing arsenic and lead exist in the regional bedrock, including rock-forming silicates (feldspar and micas), sulfide minerals formed during diagenesis (for example, arsenic-rich pyrite), and sulfide and oxide minerals that formed as a result of Silurian metamorphic and igneous events (for example, arsenopyrite, galena, iron-oxides, and arsenic-sulfides). A young group of secondary minerals (for example, iron-hydroxides, arsenic-hydroxides, lead-sulfate, and arsenic-jarosite) formed from recent weathering and pedogenic processes.

  18. 用酒石酸等有机酸清洗镉锌、镉镍复合污染土壤%Remediation of Soils Co-contaminated with Cd-Zn and Cd-Ni by Washing with Oranic Acids

    Institute of Scientific and Technical Information of China (English)

    吴俭; 潘伟斌; 林瑞聪; 赖彩秀; 詹淑威

    2015-01-01

    针对受镉锌复合污染的A区土壤和受镉镍污染的B区土壤,借鉴BCR分级提取的思路,设计了用醋酸、柠檬酸、酒石酸及琥珀酸四种有机酸与草酸组合两步振荡清洗工艺,去除土壤中环境风险较大的重金属形态,并比较了单独用柠檬酸、酒石酸振荡清洗的效果,探讨了超声波对酒石酸清洗的强化作用。结果表明:先用0.1 mol·L-1柠檬酸或酒石酸振荡清洗16 h,再用0.2 mol·L-1草酸振荡清洗16 h的两步清洗法对2种土壤目标重金属去除率最高;单独用0.1 mol·L-1酒石酸振荡清洗2 h对A区Cd、Zn和Ca的清洗率分别为30.74%、25.59%和15.86%,对B区土壤Cd、Ni和Ca的清洗率分别为47.36%、6.89%和23.92%。酒石酸能有效去除目标重金属,同时洗出的常量元素Ca较柠檬酸少,是较理想的清洗剂。超声波(功率400 W,频率20 kHz)可以强化酒石酸对重金属的清洗效果,超声30 min对2种土壤目标重金属的清洗率与单独用酒石酸振荡清洗2 h相当。%Soil flushing is one of remediation techniques for metals contaminated soils. Here an effective soil washing process was studied in two metal-contaminated sites, namely soil A, which was polluted by Cd and Zn, and soil B, which was polluted by Cd and Ni. A two-step washing method using oxalic acid combined with four different acids, such as acetic acid, citric acid, tartaric acid and succinic acid, was e-valuated in terms of removal of bioavailable portion of heavy metals. In addition, soil washing with citric acid or tartaric acid alone was con-ducted. Enhancing effect of ultrasonic wave on metal washing by tartaric acid was also investigated. Results showed that the removal effi-ciencies of two-step washing process using citric acid or tartaric acid(0.1 mol·L-1, for 16 h)and oxalic acid(0.2 mol·L-1, for 16 h)sequen-tially were the highest. Under tartaric acid alone (0.1 mol·L-1, t=2 h), the removal of Cd, Zn and Ca was

  19. IMPACT OF LEATHER PROCESSING INDUSTRIES ON CHROMIUM CONCENTRATION IN GROUNDWATER SOUTH OF CHENNAI CITY, INDIA

    Science.gov (United States)

    Elango, L.; Brindha, K.; G. Rajesh, V.

    2009-12-01

    The groundwater quality is under threat due to disposal of effluents from a number of industries. Poor practice of treatment of wastes from tanning industries or leather processing industries lead to pollution of groundwater. This study was carried out with the objective of assessing the impact of tanneries on groundwater quality in Chromepet area which is a part of the metropolitan area of Chennai, Tamil Nadu, India. This area serves as the home town for a number of small and large scale tanning industries. People in certain parts of this area depend on the groundwater for their domestic needs as there is no piped drinking water supply system. Topographically this region is generally flat with gentle slope towards east and north east. The charnockite rocks occur as basement at the depth of about 15m from the surface of this area. Weathered charnockite rock occurs at the depth from 7m to 15m from the ground surface. The upper layer consists of loamy soil. Groundwater occurs in the unconfined condition at a depth from 0.5m to 5m. Thirty six groundwater samples were collected during March 2008 and the groundwater samples were analysed for their heavy metal (chromium) content using atomic absorption spectrophotometer. Bureau of Indian Standards (BIS) recommended the maximum permissible limit of chromium in drinking water as 0.05 mg/l. Considering this, it was found that 86% of the groundwater samples possessed concentration of chromium above the maximum permissible limit recommended by BIS. The tanneries use chrome sulphate to strengthen the leather and make it water repellent. The excess of chromium gets washed off and remains in the wastewater. This wastewater is disposed into open uncovered drains either untreated or after partial treatment. Thus the chromium leaches through the soil and reaches the groundwater table. Apart from this, there is also huge quantity of solid waste resulting from the hides and skins which are dumped off without suitable treatment. The

  20. Remedial Measures for Counterbalancing the After Effects of Green Revolution on the Georesources of Groundwater, Land and Soil in Haryana, India

    Science.gov (United States)

    Sharma, A.; Lunkad, S. K.

    2008-05-01

    In Haryana, one of the wheat granaries of India where water resources have depleted to a critical level (1050 m3 /year/person), groundwater alone has 53% share in the irrigation, the remaining 47% comes from canal system of glacier-fed rivers, viz., Yamuna and Satluj originating from Himalayas. The Green Revolution (1971-1990, intensive phase) enabled this small state to become an agro-economic state in northern alluvial plains of India. Though occupying 1.3 % geographical area and containing 2% of the population of India, it produces country's 13% wheat and about 3% quality rice besides other cereals, oil seeds, sugarcane and cotton. However, Haryana paid a heavy price for the impressive agricultural development- one-third of the irrigated land is salinity affected, water level declined by 3-12 m in twelve of its nineteen districts and excessive nitrate levels in the groundwater (114-1800 mg/l) have rendered the groundwater non-potable in many areas. Groundwater in the arid western Haryana is mostly saline (TDS > 4000 mg/l) and irrational canal irrigation has paradoxically raised the water-table by 3-9m in seven districts causing waterlogging over 2346 km2 land of which 251 km2 is fully waterlogged. In the land use pattern 131,000 ha prime cultivable land (about 3% of the total) has been lost to urbanization jeopardizing the FOOD SECURITY. One possible way to arrest the degradation of groundwater and soil, is to switch to dryland farming. This would involve change in the irrigation method as well as proper selection and rotation of food crops like barley, sorghum, maize, different types of beans (pulses) and oil seeds like groundnut, sunflower, mustard, etc. and restricted use of chemical fertilizers and pesticides. Dryland farming could go hand in hand with the plantation of fruit trees, grasses and medicinal plants suitable to this agro-climatic zone, and animal husbandry. The same considerations also hold good to the adjoining eastern Rajasthan.

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

    DEFF Research Database (Denmark)

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

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

  2. Remediation of groundwater contaminated with MTBE and benzene: the potential of vertical-flow soil filter systems

    NARCIS (Netherlands)

    Afferden, M. van; Rahman, K.Z.; Mosig, P.; De Biase, C.; Thullner, M.; Oswald, S.E.; Müller, R.A.

    2011-01-01

    Field investigations on the treatment of MTBE and benzene from contaminated groundwater in pilot or full-scale constructed wetlands are lacking hugely. The aim of this study was to develop a biological treatment technology that can be operated in an economic, reliable and robust mode over a long per

  3. Identifying groundwater recharge connections in the Moscow (USA) sub-basin using isotopic tracers and a soil moisture routing model

    NARCIS (Netherlands)

    Candel, J.H.J.; Brooks, Erin; Sanchez-Murillo, Ricardo; Grader, George; Dijksma, R.

    2016-01-01

    Globally, aquifers are suffering from large abstractions resulting in groundwater level declines. These declines can be caused by excessive abstraction for drinking water, irrigation purposes or industrial use. Basaltic aquifers also face these conflicts. A large flood basalt area (1.1 × 105 km2) ca

  4. Remediation of groundwater contaminated with MTBE and benzene: the potential of vertical-flow soil filter systems

    NARCIS (Netherlands)

    Afferden, M. van; Rahman, K.Z.; Mosig, P.; De Biase, C.; Thullner, M.; Oswald, S.E.; Müller, R.A.

    2011-01-01

    Field investigations on the treatment of MTBE and benzene from contaminated groundwater in pilot or full-scale constructed wetlands are lacking hugely. The aim of this study was to develop a biological treatment technology that can be operated in an economic, reliable and robust mode over a long

  5. 27 CFR 19.328 - Wash water.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Wash water. 19.328 Section... THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Production Chemical By-Products § 19.328 Wash water. Water used in washing chemicals to remove spirits therefrom may be run into a wash tank or a distilling...

  6. Enhanced sludge washing evaluation plan

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, R.D.

    1994-09-01

    The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices.

  7. Contamination of ground water, surface water, and soil, and evaluation of selected ground-water pumping alternatives in the Canal Creek area of Aberdeen Proving Ground, Maryland

    Science.gov (United States)

    Lorah, Michelle M.; Clark, Jeffrey S.

    1996-01-01

    Chemical manufacturing, munitions filling, and other military-support activities have resulted in the contamination of ground water, surface water, and soil in the Canal Creek area of Aberdeen Proving Ground, Maryland. Chlorinated volatile organic compounds, including 1,1,2,2-tetrachloroethane and trichloroethylene, are widespread ground-water contaminants in two aquifers that are composed of unconsolidated sand and gravel. Distribution and fate of chlorinated organic compounds in the ground water has been affected by the movement and dissolution of solvents in their dense immiscible phase and by microbial degradation under anaerobic conditions. Detection of volatile organic contaminants in adjacent surface water indicates that shallow contaminated ground water discharges to surface water. Semivolatile organic compounds, especially polycyclic aromatic hydrocarbons, are the most prevalent organic contaminants in soils. Various trace elements, such as arsenic, cadmium, lead, and zinc, were found in elevated concentrations in ground water, surface water, and soil. Simulations with a ground-water-flow model and particle tracker postprocessor show that, without remedial pumpage, the contaminants will eventually migrate to Canal Creek and Gunpowder River. Simulations indicate that remedial pumpage of 2.0 million gallons per day from existing wells is needed to capture all particles originating in the contaminant plumes. Simulated pumpage from offsite wells screened in a lower confined aquifer does not affect the flow of contaminated ground water in the Canal Creek area.

  8. Presence of Epsilon HCH Together with Four Other HCH Isomers in Drinking Water, Groundwater and Soil in a Former Lindane Production Site.

    Science.gov (United States)

    Fuscoletti, Valentina; Achene, Laura; Gismondi, Fabrizio; Lamarra, Daniela; Lucentini, Luca; Spina, Salvatore; Veschetti, Enrico; Turrio-Baldassarri, Luigi

    2015-07-01

    In the frame of a long-standing action of remediation of industrial soil and prevention of water pollution, a monitoring of the drinking water of the Italian town of Colleferro was performed by the ISS. The town has 22,000 inhabitants and is adjacent to a big industrial site where HCH was produced. Industrial wastes were buried in the site, eventually contaminating superficial aquifers, while a canal serving the industrial plant spread the contamination into the Sacco river and thence to the agricultural soil and to cow milk. The contamination of superficial aquifers engendered fears of pollution of the deep aquifers whence the town draws its drinking water. The results of the monitoring indicate that there is no risk for the population from consumption of the water. In one of the wells the ε-HCH was the main isomer reaching a concentration of 66 ng/L: so far the presence of this isomer in water was never reported. The paper also summarily reports the main features of soil and superficial groundwater pollution in the area and briefly describes the main actions taken by the authorities.

  9. Results of soil, ground-water, surface-water, and streambed-sediment sampling at Air Force Plane 85, Columbus, Ohio, 1996

    Science.gov (United States)

    Parnell, J.M.

    1997-01-01

    The U.S. Geological Survey (USGS), in cooperation with Aeronautical Systems Center, Environmental Management Directorate, Restoration Division, prepared the Surface- and Ground- Water Monitoring Work Plan for Air Force Plant 85 (AFP 85 or Plant), Columbus, Ohio, under the Air Force Installation Restoration Program to characterize any ground-water, surface-water, and soil contamination that may exist at AFP 85. The USGS began the study in November 1996. The Plant was divided into nine sampling areas, which included some previously investi gated study sites. The investigation activities included the collection and presentation of data taken during drilling and water-quality sampling. Data collection focused on the saturated and unsatur ated zones and surface water. Twenty-three soil borings were completed. Ten monitoring wells (six existing wells and four newly constructed monitoring wells) were selected for water-quality sam pling. Surface-water and streambed-sediment sampling locations were chosen to monitor flow onto and off of the Plant. Seven sites were sampled for both surface-water and streambed-sediment quality. This report presents data on the selected inorganic and organic constituents in soil, ground water, surface water, and streambed sediments at AFP 85. The methods of data collection and anal ysis also are included. Knowledge of the geologic and hydrologic setting could aid Aeronautical Systems Center, Environmental Management Directorate, Restoration Division, and its governing regulatory agencies in future remediation studies.

  10. The implications of soil acidification on a future HLW repository. Pt 2. Influence on deep granitic groundwater. The Klipperaas study site as test case.

    Energy Technology Data Exchange (ETDEWEB)

    Wersin, P.; Bruno, J. [MBT Tecnologia Ambiental, Cerdanyola (Spain); Laaksoharju, M. [Geopoint AB, Spaanga (Sweden)

    1994-05-01

    The effect of acidification on deep groundwater is assessed with a geochemical box model based on the STEADYQL code. The application of the model to the Klipperaas study site shows a remarkable agreement between observed and predicted groundwater composition and offers an adequate description of the geochemical evolution of the aquifer. Proton fluxes are shown to be controlled mainly by calcite weathering and organic carbon degradation processes. The impact of increased acidification is evaluated on the basis of various test cases and by including the soil compartment in the model framework. The results indicate that calcite weathering will be increased by a factor of two to three as a result of increased acidification. Furthermore, the calculations suggest that, once the powerful carbonate buffer is depleted, the buffer capacity is provided mainly by anaerobic respiration and ion exchange processes. Further ongoing acidic loading would lead to neutralization of alkalinity fluxes leaving the system with a very low buffering capacity towards fluctuations in proton fluxes. Estimation of time scales of aquifer acidification was assessed under the focus of calcite depletion with aid of two acidification scenarios. These predict a time range of 12400 to 370000 years for calcite depletion to take place down to 500 meters depth. It is suggested from inherent model assumptions that these estimated time scales are conservative. 53 refs.

  11. Experiments on the movement of pesticides in sandy soils to groundwater : prospects of testing preferential transport models

    NARCIS (Netherlands)

    Leistra, M.; Boesten, J.J.T.I.

    2012-01-01

    Many agricultural areas with humic-sandy and loamy-sandy soils are used also for the extraction of water for drinking-water supply. Model concepts have been developed for the fast preferential transport of plant protection products (pesticides) in such soils, e.g. by fingered and funneled flow. An i

  12. NGAWANG JIGME'S MODERN WASH PAINTINGS

    Institute of Scientific and Technical Information of China (English)

    KELZANG; DORJE

    2007-01-01

    Having received a thorough college education.Ngawang Jigme naturally expresses his academic knowledge and skills through his washing paintings.Though he grew up on the plateau cating Tsampa and yak flesh,drinking yak buttered tea,living in the clear atmosphere,sunny sky and mountain scenery,he would hardly be expected to tolerate the monotone world of wash painting,which adopts black and white as its principal theme and acknow ledges"blur impression"as the ultimate aim.He strives for total absorption int...

  13. Delineation of soil and groundwater contamination using geophysical methods at a waste disposal site in Canakkale, Turkey.

    Science.gov (United States)

    Kaya, M Ali; Ozürlan, Gülçin; Sengül, Ebru

    2007-12-01

    Direct current (DC) resistivity, self potential (SP) and very low frequency electromagnetic (VLF-EM) measurements are carried out to detect the spread of groundwater contamination and to locate possible pathways of leachate plumes, that resulted from an open waste disposal site of Canakkale municipality. There is no proper management of the waste disposal site in which industrial and domestic wastes were improperly dumped. Furthermore, because of the dumpsite is being located at the catchment area borders of a small creek and is being topographically at a high elevation relative to the urban area, the groundwater is expected to be hazardously contaminated. Interpretations of DC resistivity geoelectrical data showed a low resistivity zone (geophysical investigations and the results of previously collected geochemical and hydrochemical measurements.

  14. Remediation of Cadmium and Lead Contaminated Farmland Soil by Washing with Combined Organic Acids and FeCl3%有机酸和FeCl3复合浸提修复Cd、Pb污染农田土壤的研究

    Institute of Scientific and Technical Information of China (English)

    李玉姣; 温雅; 郭倩楠; 祝媛; 董长勋; 胡鹏杰

    2014-01-01

    采用振荡浸提方法,研究了有机酸(柠檬酸、酒石酸)与FeCl3复合浸提对Cd、Pb污染农田土壤重金属的去除效果和影响因素,测定了浸提前后土壤中重金属形态和浸提液中常量元素含量。结果表明,柠檬酸(100 mmol·L-1)和FeCl3(20 mmol·L-1)复合浸提,对土壤中Cd、Pb的去除效率分别达到了40.7%和20.9%,酒石酸(100 mmol·L-1)和FeCl3(20 mmol·L-1)复合浸提,对Cd、Pb的去除效率分别达到了42.6%和16.5%,均高于相同浓度有机酸、FeCl3单独浸提的去除效率。有机酸- FeCl3对重金属的去除率随pH值升高而减少。液固质量比为5∶1、浸提时间为24 h、浸提3次比较适宜;有机酸-FeCl3对Cd的去除主要是交换态(77.3%~79.8%)和铁锰氧化态(86.7%~87.0%),有机结合态几乎没有变化;对Pb的去除主要是铁锰氧化态(70.0%~70.8%)和有机结合态(58.8%~66.0%),交换态显著增加至24.2%~24.5%,Cd、Pb碳酸盐结合态几乎消失,残渣态无变化。污染土壤中的Pb经过多次浸提,去除率可显著提高,连续3次浸提达到47.0%~48.2%。%Soil washing is one option to remediate heavy metal contaminated soils. The present study examined the removal efficiency of cad-mium(Cd)and lead(Pb)from a farmland soil by batch extraction with mixture of organic acid(citric acid or tartaric acid)and FeCl3. Metal fractions before and after soil washing were also determined. The Cd and Pb removal efficiency from the soil was up to 40.7%and 20.9%for mixture of citric acid(100 mmol·L-1)and FeCl3(20 mmol·L-1), and up to 42.6%and 16.5%for mixture of tartaric acid(100 mmol·L-1) and FeCl3(20 mmol·L-1), respectively. The metal removal efficiency was higher for mixed reagents than single reagent. Increasing pH of washing solution decreased the removal efficiency of heavy metals. The optimum washing conditions were liquid to solid ratio of 5∶1

  15. Sustainable Irrigation with Brackish Groundwater in Heilonggang Region, China

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Saline groundwater is widely distributed in Heilonggang region. While deep confined water is being mined, saline water has not been used in most part of the region. Extension of saline water irrigation is of significance to resolve water shortage, slow down environmental degradation and support the sustainable development of the local agriculture. Four key points are proposed to be managed by comprehensive measures: (1) adapting salt-resistant ability; (2) reducing salt input; (3) decreasing soil surface evaporation and salt accumulation in the root zone, and (4) washing away salt from the root zone. Experiments and farming practices demonstrated that brackish water with TDS (total dissolved solids) of 2-5 g/l can be used for crop irrigation. For example, winter wheat can be sustainably irrigated by brackish water with a water limitation of 120 mm every year. Irrigation in combination with different comprehensive measures can increase the efficiency of saline water irrigation.

  16. Assessment and remediation of a historical pipeline release : tools, techniques and technologies applied to in-situ/ex-situ soil and groundwater remediation

    Energy Technology Data Exchange (ETDEWEB)

    Reid, N. [EBA Engineering Consultants Ltd., Calgary, AB (Canada); Kohlsmith, B. [Kinder Morgan Canada Inc., Calgary, AB (Canada)

    2008-07-01

    Tools, techniques, and technologies applied to in-situ/ex-situ soil and groundwater remediation were presented as part of an assessment and remediation of a historical pipeline release. The presentation discussed the initial assessment, as well as a discussion of remediation of hydrophobic soils, re-assessment, site specific criteria, a remediation trial involving bioventing and chemical oxidation, and a full scale remediation. The pipeline release occurred in the summer of 1977. The event was followed by a complete surface remediation with a significant amount of topsoil being removed and replaced. In 2004, a landowner complained of poor crop growth in four patches near the area of the historical spill. An initial assessment was undertaken and several photographs were presented. It was concluded that a comprehensive assessment set the base for a careful staged approach to the remediation of the site including the establishment of site specific criteria. The process was made possible with a high level of communication between all stakeholders. In addition, the most appropriate solution for the site was realized. figs.

  17. Recrystallization and stability of Zn and Pb minerals on their migration to groundwater in soils affected by Acid Mine Drainage under CO2 rich atmospheric waters.

    Science.gov (United States)

    Goienaga, N; Carrero, J A; Zuazagoitia, D; Baceta, J I; Murelaga, X; Fernández, L A; Madariaga, J M

    2015-01-01

    The extent of vertical contamination is intimately related to the soil solution and surface chemistry of the soil matrix with reference to the metal and waste matrix in question. The present research demonstrated the impact that the dissolved CO2 of the meteoric waters, which acidify the environment with pH values below 4, has in the increase of the metal mobility. Although under the given conditions the Zn remains mainly dissolved, the initial PbS and ZnS have evolved into newly formed secondary carbonates and sulphates (i.e., hydrozincite, gunningite, hydrocerussite) that can be found in the efflorescences. The chemical simulation done on the weathering of the original sulphide ores for the formation of these secondary minerals has proved the transient storage mainly of Pb. Nonetheless, many of the minerals formed inside the galleries will be easily dissolved in the next rains and release in an ionic form to the groundwater. The analytical procedure exposed has been proved to be useful not only for the characterization of AMD but also for the prediction of the mobility of metals.

  18. Identifying groundwater recharge connections in the Moscow (USA) sub-basin using isotopic tracers and a soil moisture routing model

    OpenAIRE

    2016-01-01

    Globally, aquifers are suffering from large abstractions resulting in groundwater level declines. These declines can be caused by excessive abstraction for drinking water, irrigation purposes or industrial use. Basaltic aquifers also face these conflicts. A large flood basalt area (1.1 × 105 km2) can be found in the Northwest of the USA. This Columbia River Basalt Group (CRBG) consists of a thick series of basalt flows of Miocene age. The two major hydrogeological units (Wanapum and Grand Ron...

  19. Soils

    Science.gov (United States)

    Emily Moghaddas; Ken Hubbert

    2014-01-01

    When managing for resilient forests, each soil’s inherent capacity to resist and recover from changes in soil function should be evaluated relative to the anticipated extent and duration of soil disturbance. Application of several key principles will help ensure healthy, resilient soils: (1) minimize physical disturbance using guidelines tailored to specific soil types...

  20. Changes in chemical composition and engineering properties of gypseous soils through leaching: an example from Mashhad, Iran

    DEFF Research Database (Denmark)

    Asghari, Somaye; Ghafoori, Mohammad; Tabatabai, Salman

    2017-01-01

    Gypseous soils are considered problematic when used as the foundation in civil engineering structures such as roads, buildings and dams, due to their solubility. These soils are resistant and have good engineering properties in their dry state. However, when saturated by rainwater or a rising...... groundwater table, the soluble minerals are washed out, resulting in the subsidence of the structures built on them. In the recent decades, buildings constructed in the Southern Mashhad Metropolitan Area, Iran, have been widely faced with this problem. Since the changes in chemical composition and engineering...

  1. 21 CFR 1250.87 - Wash water.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wash water. 1250.87 Section 1250.87 Food and Drugs... Sanitation Facilities and Conditions on Vessels § 1250.87 Wash water. Where systems installed on vessels for wash water, as defined in § 1250.3(n), do not comply with the requirements of a potable water...

  2. 7 CFR 58.429 - Washing machine.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Washing machine. 58.429 Section 58.429 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....429 Washing machine. When used, the washing machine for cheese cloths and bandages shall be...

  3. Alternative antimicrobial commercial egg washing procedures

    Science.gov (United States)

    Commercial table eggs are washed prior to packaging. Standard wash procedures use an alkaline pH and warm water. If a cool water method could be developed that would still provide a microbiologically safe egg, the industry may save energy costs associated with water heating. Four wash procedures ...

  4. assessment of soil wash and soil erodibility indices on miniature ...

    African Journals Online (AJOL)

    Osondu

    1976-02-03

    Feb 3, 1976 ... and organic matter content were determined in the laboratory by the ... due to human activities can set in motion certain negative geomorphic processes such as accelerated ..... rehabilitation of the sites, organic matter.

  5. Tracey - a simulation model of trace element fluxes in soil-plant system for long-term assessment of a radioactive groundwater contamination

    Energy Technology Data Exchange (ETDEWEB)

    Gaerdenaes, Annemieke (Dept. of Soil and Environment, Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)); Eckersten, Henrik (Dept. of Ecology and Crop Production, Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)); Reinlert, Andre (Dept. of Physical Geography and Ecosystems Analysis, Lund Univ., Lund (Sweden)); Gustafsson, David; Jansson, Per-Erik (Dept. Land and WaterResources, Royal Inst. of Technology, Stockholm (Sweden)); Ekstroem, Per-Anders; Avila, Rodolfo (Facilia AB, Bromma (Sweden)); Greger, Maria (Dept. of Botany, Stockholm Univ., Stockholm (Sweden))

    2009-10-15

    We developed a general trace element model called Tracey to simulate dynamically the possible accumulation of radionuclides as a result of an long-term radioactive contamination of groundwater in terrestrial ecosystems. The overall objectives of the study are to: 1) Develop and evaluate a multi-compartmental model that dynamically simulates the transport and accumulation of a radionuclide in the soil-plant system at a time scale relevant for risk assessment of nuclear fuel waste; and 2) Asses the possible accumulation of radionuclide in terrestrial ecosystems due to an eventual long-term continuous radioactive groundwater contamination. Specific objectives were to assess: - The proportion of the contamination accumulated and where it is stored in the ecosystem. - The importance of the plant uptake approach for accumulation of radionuclides. - The most important radionuclide properties and ecosystem characteristics for accumulation and losses. - The proportion of the contamination lost and how is it lost. - The circumstances which stimulated export of radionuclides to other ecosystems. The model presented here, called Tracey, is a stand-alone version to allow for long simulation periods relevant for the time scale of risk assessment of nuclear waste (i.e. several thousand years) with time steps as short as one day. Tracey is a multi-compartmental model in which fluxes and storage of radionuclide are described for different plant parts and for several soil layers. Each layer includes pools of slowly and quickly decomposing litter, humus, solved and absorbed trace element. The trace element fluxes are assumed to be proportional to either water or carbon fluxes, these fluxes are simulated using the dynamic model CoupModel for fluxes of water, carbon, nitrogen and carbon in terrestrial ecosystems. Two different model approaches were used to describe plant uptake of radionuclides. The one called passive uptake approach is driven by water uptake and the one called active

  6. An evaluation of remote sensing derived soil pH and average spring groundwater table for ecological assessments

    NARCIS (Netherlands)

    Roelofsen, H.D.; Bodegom, van P.M.; Kooistra, L.; Amerongen, van L.; Witte, J.M.

    2015-01-01

    Ecological assessments such as species distribution modelling and benchmarking site quality towards regulations often rely on full spatial coverage information of site factors such as soil acidity, moisture regime or nutrient availability. To determine if remote sensing (RS) is a viable alternative

  7. The Mechanism of Groundwater Salinization and Its Control in the Yaoba Oasis, Inner Mongolia

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The arid area is one of the most concerned areas among the water resources researchers and economists. Northwest China will be an important developing region of China in the 21st century. Yaoba is a well-irrigation oasis within this arid area, which is located in the Alxa area west of the Helan Mountains and next to the Tengger desert in the east. It has contributed greatly to the local stock raising and agriculture since its development in 1970. However, the groundwater which the oasis depends on to survive has been getting salinized gradually and more serious in recent years.A comprehensive study was carried out using the methods of groundwater environment isotope analysis, lithofacies and palaeogeography, calculations of water-rock interaction and the existing form of chemical components in groundwater etc. It has been found that the salinization of groundwater is mainly caused by reinfiltration water solving the salt in soil which is deposited simultaneously with the sediments and accumulated in the vadose zone due to strong evaporation in the arid climate for the running of an irrigation scheme.The saline groundwater in the Taosu Lake area southwest of the oasis is preliminarily regarded as the main source of groundwater salinization. However, it has been found that the groundwater has great differences in the D, 18O, H3 and NO3- concentrations with that in the oasis, that is, the former plays only a limited role in the salinization of groundwater in the oasis.The HST3D model (a computer code for the simulation of heat and solute transport in a three-dimensional groundwater system) was used to simulate the TDS movement in the oasis. A good simulation result has been obtained with the mean simulation error of 4.7% and the simulation trend is reasonable. It is proved that there is 3.0- 4.0′ 105 m3/a of reinfiltrated irrigation water in 3 main spots in the oasis. The oasis irrigation manner, winter irrigation to wash salt, the increase of wheat planting area

  8. Application of the Netherlands Groundwater Model, LGM, for calculating concentration of nitrate and pesticides at abstraction wells in sandy soil areas of the Netherlands

    NARCIS (Netherlands)

    Kovar K; Pastoors MJH; Tiktak A; Gaalen FW van; LBG, LWD

    1998-01-01

    In a study aimed at assessing the impact of historical and future solute leaching into saturated groundwater, the quasi-three-dimensional RIVM groundwater model, LGM (version 2), was used for calculating pathlines, travel times and concentration breakthrough curves at 165 groundwater abstraction loc

  9. The Study on the Mechanism of Improving of P/C Fabric Soil Release Property by Cellulase Washing%纤维素酶洗涤对提高涤棉织物易去污性的作用机理

    Institute of Scientific and Technical Information of China (English)

    吴颖喆; 邵建中; 付国栋

    2012-01-01

    The aim of this article is to explain why soil release property of cotton-containing fabric can be improved after cellulase washing, and characterize the physicochemical properties of P/C fabric like wettability, abrasion resistance, crystalline and hydrophilic group content after cellulase washing by drip method, Martindale friction-SEM, XRD and copper value analysis. The result shows that after cellulase washing, the cotton fiber surface of P/C fabric becomes more brittle, and the external force can remove the brittle fibers of fabric surface easily, also remove the soil on the fibers. Meanwhile, the crystallinity of cotton fiber is decreased by cellulase, and the 1, 4-(3 glycoside bond is cut to form the aldehyde group. It can increase the hydrophilicity of cotton fiber and enhance the wettability of P/C fabric, so that soil release property of P/C fabric is improved.%为探明纤维素酶洗涤提高含棉织物易去污性的机理,采用滴水法、马丁代尔磨擦—扫描电镜联合分析法、XRD分析和铜值法等测试分析技术对涤棉织物经纤维素酶洗涤后的润湿性、耐磨性、表面形态、结晶度、亲水基团含量等理化性能进行分析表征.结果表明:经纤维素酶洗涤后,棉纤维表面发生脆损,涤棉织物的耐磨性下降,在外力作用下易使织物表面的纤维脱落从而带走污垢;同时,纤维素酶洗涤使棉纤维的结晶度有所下降,纤维素大分子的β-1,4-甙键部分切断形成醛基,从而提高了棉纤维的亲水性,增加了涤棉织物的润湿性,进而使涤棉织物的易去污性得以改善.

  10. Wash resistance of insecticide-treated materials.

    Science.gov (United States)

    Ordóñez González, José; Kroeger, Axel; Aviña, Ana Isabel; Pabón, Eulides

    2002-01-01

    The effectiveness of insecticide-treated materials (ITMs) for malaria control is reduced by washing them. This research in Colombia and Bolivia investigated the resistance of different insecticide formulations and, in particular, a commercially available impregnated bednet (PermaNet) which provides chemical protection for the insecticide. The fabrics studied were all polyester; the pyrethroids used for impregnation were deltamethrin (tablet and suspension concentrate both at 25 mg/m2 target dose), lambdacyhalothrin (capsule suspension at 15 mg/m2; laboratory study only), alphacypermethrin (suspension concentrate at 40 mg/m2) and, in the case of PermaNet, deltamethrin (55 mg/m2). The indicator of wash resistance was Anopheles spp. mortality (using the bioassay cone method) before and after different numbers and intensities of washing. When the fabrics were washed under controlled conditions, gently with water and a bar of soap, the wash resistance of all formulations was good (100% Anopheles mortality after 3 washes). However, when the impregnated nets were soaked for 30-60 min and washed with soap powder and tap water by local women in the usual way, the mortality after 4 washes declined considerably (43.5% and 41.3% for deltamethrin tablets and liquid respectively when washing every second day). Alphacypermethrin showed slightly better results after 3 washes every 7th day compared to deltamethrin tablets (63.8% and 43.3% mortality, respectively). The wash resistance offered by PermaNet was much better and longer lasting: Anopheles mortality after 4 washes was 92.6%, after 10 washes 83.7% and after 20 washes 87.1%. The limitations of commercially available wash-resistant nets are, however, their limited accessibility and the difficulty of replacing all existing bednets with a new product.

  11. Subsurface Drip Irrigation As a Methold to Beneficiallly Use Coalbed Methane Produced Water: Initial Impacts to Groundwater, Soil Water, and Surface Water

    Energy Technology Data Exchange (ETDEWEB)

    Engle, M.A.: Bern, C: Healy, R: Sams, J: Zupancic, J.: Schroeder, K.

    2009-10-18

    Coalbed methane (CBM) currently accounts for >8% of US natural gas production. Compared to traditional sources, CBM co-produces large volumes of water. Of particular interest is CBM development in the Powder River Basin of Wyoming and Montana, the 2nd largest CBM production field in the US, where CBM produced waters exhibit low to moderate TDS and relatively high sodium-adsorption ratio (SAR) that could potentially impact the surface environment. Subsurface drip irrigation (SDI) is an emerging technology for beneficial use of pre-treated CBM waters (injectate) which are emitted into the root zone of an agricultural field to aid in irrigation. The method is designed to minimize environmental impacts by storing potentially detrimental salts in the vadose zone. Research objectives include tracking the transport and fate of the water and salts from the injected CBM produced waters at an SDI site on an alluvial terrace, adjacent to the Powder River, Johnson County, Wyoming. This research utilizes soil science, geochemical, and geophysical methods. Initial results from pre-SDI data collection and the first 6-months of post-SDI operation will be presented. Substantial ranges in conductivity (2732-9830 {micro}S/cm) and dominant cation chemistry (Ca-SO{sub 4} to Na-SO{sub 4}) have been identified in pre-SDI analyses of groundwater samples from the site. Ratios of average composition of local ground water to injectate demonstrate that the injectate contains lower concentrations of most constituents except for Cr, Zn, and Tl (all below national water quality standards) but exhibits a higher SAR. Composition of soil water varies markedly with depth and between sites, suggesting large impacts from local controls, including ion exchange and equilibrium with gypsum and carbonates. Changes in chemical composition and specific conductivity along surface water transects adjacent to the site are minimal, suggesting that discharge to the Powder River from groundwater underlying the

  12. evaluation of models for assessing groundwater vulnerability to ...

    African Journals Online (AJOL)

    DR. AMINU

    Key words: Groundwater, Vulnerability, Pollution, Nigeria. INTRODUCTION ... natural groundwater vulnerability: net recharge, soil properties, unsaturated zone ... such as dispersion, oxidation, natural attenuation, sorption etc. A low depth to ...

  13. Response of the microbial community to seasonal groundwater level fluctuations in petroleum hydrocarbon-contaminated groundwater.

    Science.gov (United States)

    Zhou, Ai-xia; Zhang, Yu-ling; Dong, Tian-zi; Lin, Xue-yu; Su, Xiao-si

    2015-07-01

    The effects of seasonal groundwater level fluctuations on the contamination characteristics of total petroleum hydrocarbons (TPH) in soils, groundwater, and the microbial community were investigated at a typical petrochemical site in northern China. The measurements of groundwater and soil at different depths showed that significant TPH residue was present in the soil in this study area, especially in the vicinity of the pollution source, where TPH concentrations were up to 2600 mg kg(-1). The TPH concentration in the groundwater fluctuated seasonally, and the maximum variation was 0.8 mg L(-1). The highest TPH concentrations were detected in the silty clay layer and lied in the groundwater level fluctuation zones. The groundwater could reach previously contaminated areas in the soil, leading to higher groundwater TPH concentrations as TPH leaches into the groundwater. The coincident variation of the electron acceptors and TPH concentration with groundwater-table fluctuations affected the microbial communities in groundwater. The microbial community structure was significantly different between the wet and dry seasons. The canonical correspondence analysis (CCA) results showed that in the wet season, TPH, NO3(-), Fe(2+), TMn, S(2-), and HCO3(-) were the major factors correlating the microbial community. A significant increase in abundance of operational taxonomic unit J1 (97% similar to Dechloromonas aromatica sp.) was also observed in wet season conditions, indicating an intense denitrifying activity in the wet season environment. In the dry season, due to weak groundwater level fluctuations and low temperature of groundwater, the microbial activity was weak. But iron and sulfate-reducing were also detected in dry season at this site. As a whole, groundwater-table fluctuations would affect the distribution, transport, and biodegradation of the contaminants. These results may be valuable for the control and remediation of soil and groundwater pollution at this site

  14. High-fluoride groundwater.

    Science.gov (United States)

    Rao, N Subba

    2011-05-01

    Fluoride (F(-)) is essential for normal bone growth, but its higher concentration in the drinking water poses great health problems and fluorosis is common in many parts of India. The present paper deals with the aim of establishment of facts of the chemical characteristics responsible for the higher concentration of F(-) in the groundwater, after understanding the chemical behavior of F(-) in relation to pH, total alkalinity (TA), total hardness (TH), carbonate hardness (CH), non-carbonate hardness (NCH), and excess alkalinity (EA) in the groundwater observed from the known areas of endemic fluorosis zones of Andhra Pradesh that have abundant sources of F(-)-bearing minerals of the Precambrians. The chemical data of the groundwater shows that the pH increases with increase F(-); the concentration of TH is more than the concentration of TA at low F(-) groundwater, the resulting water is represented by NCH; the TH has less concentration compared to TA at high F(-) groundwater, causing the water that is characterized by EA; and the water of both low and high concentrations of F(-) has CH. As a result, the F(-) has a positive relation with pH and TA, and a negative relation with TH. The operating mechanism derived from these observations is that the F(-) is released from the source into the groundwater by geochemical reactions and that the groundwater in its flowpath is subjected to evapotranspiration due to the influence of dry climate, which accelerates a precipitation of CaCO(3) and a reduction of TH, and thereby a dissolution of F(-). Furthermore, the EA in the water activates the alkalinity in the areas of alkaline soils, leading to enrichment of F(-). Therefore, the alkaline condition, with high pH and EA, and low TH, is a more conducive environment for the higher concentration of F(-) in the groundwater.

  15. Can we monitor groundwater head variation from space? Coupling ERS spaceborne microwave observations to groundwater dynamics

    NARCIS (Netherlands)

    Sutanudjaja, E. H.; de Jong, S. M.; van Geer, F. C.; Bierkens, M. F. P.

    2012-01-01

    The objective of this study is to investigate whether the time series of a remote sensing based soil moisture product, referred as the European Remote Sensing Soil Water Index (ERS SWI), correlates to in-situ observations of groundwater heads; and can thus be used for groundwater head prediction. As

  16. Tracey - a simulation model of trace element fluxes in soil-plant system for long-term assessment of a radioactive groundwater contamination

    Energy Technology Data Exchange (ETDEWEB)

    Gaerdenaes, Annemieke (Dept. of Soil and Environment, Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)); Eckersten, Henrik (Dept. of Ecology and Crop Production, Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)); Reinlert, Andre (Dept. of Physical Geography and Ecosystems Analysis, Lund Univ., Lund (Sweden)); Gustafsson, David; Jansson, Per-Erik (Dept. Land and WaterResources, Royal Inst. of Technology, Stockholm (Sweden)); Ekstroem, Per-Anders; Avila, Rodolfo (Facilia AB, Bromma (Sweden)); Greger, Maria (Dept. of Botany, Stockholm Univ., Stockholm (Sweden))

    2009-10-15

    We developed a general trace element model called Tracey to simulate dynamically the possible accumulation of radionuclides as a result of an long-term radioactive contamination of groundwater in terrestrial ecosystems. The overall objectives of the study are to: 1) Develop and evaluate a multi-compartmental model that dynamically simulates the transport and accumulation of a radionuclide in the soil-plant system at a time scale relevant for risk assessment of nuclear fuel waste; and 2) Asses the possible accumulation of radionuclide in terrestrial ecosystems due to an eventual long-term continuous radioactive groundwater contamination. Specific objectives were to assess: - The proportion of the contamination accumulated and where it is stored in the ecosystem. - The importance of the plant uptake approach for accumulation of radionuclides. - The most important radionuclide properties and ecosystem characteristics for accumulation and losses. - The proportion of the contamination lost and how is it lost. - The circumstances which stimulated export of radionuclides to other ecosystems. The model presented here, called Tracey, is a stand-alone version to allow for long simulation periods relevant for the time scale of risk assessment of nuclear waste (i.e. several thousand years) with time steps as short as one day. Tracey is a multi-compartmental model in which fluxes and storage of radionuclide are described for different plant parts and for several soil layers. Each layer includes pools of slowly and quickly decomposing litter, humus, solved and absorbed trace element. The trace element fluxes are assumed to be proportional to either water or carbon fluxes, these fluxes are simulated using the dynamic model CoupModel for fluxes of water, carbon, nitrogen and carbon in terrestrial ecosystems. Two different model approaches were used to describe plant uptake of radionuclides. The one called passive uptake approach is driven by water uptake and the one called active

  17. Washing and Laundering on Board I.N. Ships with Sea Water

    Directory of Open Access Journals (Sweden)

    Sreenivas Rao

    1956-01-01

    Full Text Available This paper deals with the use of synthetic detergents for washing and laundering on board I.N. Ships using sea water. Soiled clothed were subjected to washing trials using various concentrations of detergents viz., Teepol and Lissapol N with sodium meta-silicate as builder. A sea water washing formula using Teepol as detergent and sodium meta-silicate as builder in equal proportions has been evolved by which fresh water can be economized to the extent of 66% when compared to ordinary soaps and fresh water.

  18. Wastewater washing screens out solids

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, D.G. [Hycor Corp., Lake Bluff, IL (United States)

    1994-09-01

    Screening, as practiced by most municipal wastewater treatment plants, involves the manual or mechanical separation of all undesirable solids that flow into the sewer system. This consists of putresible or rotting material and inert solids such as paper, food, leaves, plastics, rubber, rocks, glass, metal and cigarette butts. These constituents, if not removed, clog downstream equipment and put a heavy load on aeration basins, dissolved air flotation equipment and digesters. Screenings washing is just entering the U.S. market with numerous benefits including increased efficiency, economics, safer work environment, and the ability to meet more stringent regulations.

  19. Sustainability appraisal tools for soil and groundwater remediation: how is the choice of remediation alternative influenced by different sets of sustainability indicators and tool structures?

    Science.gov (United States)

    Beames, Alistair; Broekx, Steven; Lookman, Richard; Touchant, Kaat; Seuntjens, Piet

    2014-02-01

    The state-of-the-science in sustainability assessment of soil and groundwater remediation is evaluated with the application of four decision support systems (DSSs) to a large-scale brownfield revitalization case study. The DSSs were used to perform sustainability appraisals of four technically feasible remediation alternatives proposed for the site. The first stage of the review compares the scope of each tool's sustainability indicators, how these indicators are measured and how the tools differ in terms of standardization and weighting procedures. The second stage of the review compares the outputs from the tools and determines the key factors that result in differing results between tools. The evaluation of indicator sets and tool structures explains why the tools generate differing results. Not all crucial impact areas, as identified by sustainable remediation forums, are thoroughly considered by the tools, particularly with regard to the social and economic aspects of sustainability. Variations in boundary conditions defined between technologies, produce distorted environmental impact results, especially when in-situ and ex-situ technologies are compared. The review draws attention to the need for end users to be aware of which aspects of sustainability are considered, how the aspects are measured and how all aspects are ultimately balanced in the evaluation of potential remediation strategies. Existing tools can be improved by considering different technologies within the same boundary conditions and by expanding indicator sets to include indicators deemed to be relevant by remediation forums. © 2013.

  20. Removal of non aqueous phase liquid liquid (NAPL) from a loam soil monitored by time domain reflectometry (TDR) technique

    Science.gov (United States)

    comegna, alessandro; coppola, Antonio; dragonetti, giovanna; ajeel, ali; saeed, ali; sommella, angelo

    2016-04-01

    Non-aqueous phase liquids (NAPLs) are compounds with low or no solubility with water. These compounds, due to the several human activities, can be accidentally introduced in the soil system and thus constitute a serious geo-environmental problem, given the toxicity level and the high mobility. The remediation of contaminated soil sites requires knowledge of the contaminant distribution in the soil profile and groundwater. Methods commonly used to characterize contaminated sites are coring, soil sampling and the installation of monitoring wells for the collection of groundwater samples. The main objective of the present research is to explore the potential application of time domain reflectometry (TDR) technique in order to evaluate the effect of contaminant removal in a loam soil, initially contaminated with NAPL and then flushed with different washing solutions. The experimental setup consist of: i) a Techtronix cable tester; ii) a three-wire TDR probe with wave guides 14.5 cm long inserted vertically into the soil samples; iii) a testing cell of 8 cm in diameter and 15 cm high; iv) a peristaltic pump for upward injection of washing solution. In laboratory, soil samples were oven dried at 105°C and passed through a 2 mm sieve. Known quantities of soil and NAPL (corn oil, a non-volatile and non-toxic organic compound) were mixed in order to obtain soil samples with different degrees of contamination. Once a soil sample was prepared, it was repacked into a plastic cylinder and then placed into the testing cell. An upward injection of washing solution was supplied to the contaminated sample with a rate q=1.5 cm3/min, which corresponds to a darcian velocity v=6.0 cm/h. The out coming fluid, from the soil column was collected, then the washing solution and oil was separated. Finally both the amount of oil that was remediated and the dielectric permittivity (measured via TDR) of the contaminated soil sample were recorded. Data collected were employed to implement a

  1. When soils become sediments: Large-scale storage of soils in sandpits and lakes and the impact of reduction kinetics on heavy metals and arsenic release to groundwater.

    Science.gov (United States)

    Vink, Jos P M; van Zomeren, Andre; Dijkstra, Joris J; Comans, Rob N J

    2017-08-01

    Simulating the storage of aerobic soils under water, the chemical speciation of heavy metals and arsenic was studied over a long-term reduction period. Time-dynamic and redox-discrete measurements in reactors were used to study geochemical changes. Large kinetic differences in the net-complexation quantities of heavy metals with sulfides was observed, and elevated pore water concentrations remained for a prolonged period (>1 year) specifically for As, B, Ba, Co, Mo, and Ni. Arsenic is associated to the iron phases as a co-precipitate or sorbed fraction to Fe-(hydr)oxides, and it is being released into solution as a consequence of the reduction of iron. The composition of dissolved organic matter (DOM) in reducing pore water was monitored, and relative contributions of fulvic, humic and hydrophylic compounds were measured via analytical batch procedures. Quantitative and qualitative shifts in organic compounds occur during reduction; DOM increased up to a factor 10, while fulvic acids become dominant over humic acids which disappear altogether as reduction progresses. Both the hydrophobic and hydrophilic fractions increase and may even become the dominant fraction. Reactive amorphous and crystalline iron phases, as well as dissolved FeII/FeIII speciation, were measured and used as input for the geochemical model to improve predictions for risk assessment to suboxic and anaerobic environments. The release of arsenic is related to readily reducible iron fractions that may be identified by 1 mM CaCl2 extraction procedure. Including DOM concentration shifts and compositional changes during reduction significantly improved model simulations, enabling the prediction of peak concentrations and identification of soils with increased emission risk. Practical methods are suggested to facilitate the practice of environmentally acceptable soil storage under water. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Soil Flushing Through a Thick Vadose Zone: Perchlorate Removal Documented at Edwards AFB, California

    Science.gov (United States)

    Battey, T. F.; Shepard, A. J.; Tait, R. J.

    2007-12-01

    There are currently few viable alternatives for perchlorate remediation in the vadose zone, particularly for the relatively thick vadose zones that are typical in the arid southwest where many perchlorate sites occur. Perchlorate in the vadose zone occurs in the form of highly soluble salts that may represent a risk to human or ecological receptors, and may also represent a threat to the underlying groundwater. A soil flushing treatability study was conducted at Edwards Air Force Base in the Mojave Desert of southern California at a site with a 129-foot thick vadose zone consisting primarily of clayey sand. This study utilized an infiltration gallery in conjunction with extraction, treatment, and re-injection of groundwater at the site, which contained perchlorate-contaminated soil and groundwater. The study objective was to evaluate the effectiveness of the infiltration gallery to 1) introduce treated groundwater back into the aquifer and 2) wash the perchlorate from the vadose zone soils to the aquifer. The infiltration gallery consisted of slotted PVC pipes within a highly permeable engineered bed of washed gravel. The initial water introduced into the gallery was amended with potassium bromide tracer. A downhole neutron probe was used to track the movement of the wetting front downward and outward from the gallery. Successive neutron measurements in vertical access tubes revealed that the introduced water reached the 125-foot bottom of the access tubes 14 weeks after the water was introduced into the gallery. The bromide tracer was detected in groundwater immediately below the gallery approximately 1 week later. The infiltration gallery was able to sustain an average flow rate of 2.3 gallons per minute. Prior to infiltration, the perchlorate concentration in groundwater below the gallery was 4,500 µg/L. Approximately 18 weeks after the start of infiltration, a perchlorate spike of 72,400 µg/L was detected below the gallery. The increase in perchlorate

  3. Toxicity test of the F-Area seep soils by laboratory lettuce seed germination and seedling growth

    Energy Technology Data Exchange (ETDEWEB)

    Eaton, D.; Murphy, C.E.

    1993-09-01

    This study is a follow-up of a similar study done by Loehle (1990). The objectives of the original study were to: (1) measure the toxicity of groundwater contaminated by the F-Area seepage basins where this water surfaces in a seepline along Fourmile Branch and (2) to evaluate the effectiveness of rainwater for washing contaminants from the soil. Results of seed germination tests show no significant difference between water extracted from one extraction of F-Area seepline soil, soil from a control area, the sixth consecutive extraction from F-Area soil, and a deionized water control. A root-growth assay on the same seeds shows a significant effect with the order of growth, first extraction of F-Area soilsoil at the F-Area seepline, but there is still some evidence of phytotoxicity in this soil. As shown previously, the cause of the toxicity is removed by soil washing, suggesting that continued improvement should be expected.

  4. Modeling soil water-salt dynamics and maize yield responses to groundwater depths and irrigations%土壤水盐与玉米产量对地下水埋深及灌溉响应模拟

    Institute of Scientific and Technical Information of China (English)

    郝远远; 徐旭; 黄权中; 黄冠华

    2014-01-01

    引黄水量的削减将进一步加剧宁夏银北灌区农业用水短缺问题,合理应用地下水进行灌溉对保障作物产量具有重要意义。为探究地下水灌溉条件下土壤水盐与作物生长的互馈机制,该研究修正了HYDRUS-1D的土壤蒸发模块,并嵌入可模拟作物生长与产量的 EPIC 模块,以此提高该模型在农田水文过程模拟中的适用性。采用2008年银北灌区不同水质灌水处理的玉米田间试验数据对模型进行了率定与验证。进一步应用该模型探寻地下水灌溉条件下,土壤水盐动态及玉米产量对地下水埋深变动及灌溉的响应规律。结果表明,玉米产量随地下水埋深增大呈现先增后减趋势,为保障玉米产量应将地下水适宜埋深控制在140~155 cm,且灌水量不宜低于现状灌水量,即玉米生育期内灌3水,每次900 m3/hm2。该研究对干旱银北灌区农业生产具有重要意义。%Reduction of water diversion from the Yellow River will intensify water shortage problems in the Yinbei Irrigation District (YID). Reasonable use of groundwater for irrigation is helpful to maintain the agricultural production. Groundwater exploitation may cause groundwater level declines in local areas. This helps to reduce the salinity accumulation in the root zone but decreases the capillary rise. Thus, it is important to figure out the responses of soil water-salt dynamics and crop yields to groundwater table fluctuations for salinity control and stable yields. In this study, HYDRUS-1D model was modified by coupling with the EPIC (erosion-productivity impact calculator) crop growth module for simulating agro-hydrological processes. The new crop module could simulate crop height, leaf area index (LAI), above-ground biomass and crop yield. The information between HYDRUS-1D and EPIC was exchanged by daily step. Root water uptake under water and salt stress was calculated with HYDRUS-1D and imported to EPIC to

  5. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2012-01-01

    Groundwater is a vital resource and also a dynamic component of the water cycle. Unconfined aquifer storage is less responsive to short term weather conditions than the near surface terrestrial water storage (TWS) components (soil moisture, surface water, and snow). However, save for the permanently frozen regions, it typically exhibits a larger range of variability over multi-annual periods than the other components. Groundwater is poorly monitored at the global scale, but terrestrial water storage (TWS) change data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission are a reasonable proxy for unconfined groundwater at climatic scales.

  6. Contain contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Mutch, R.D. Jr.; Caputi, J.R. [Eckenfelder, Inc., Mahwah, NJ (United States); Ash, R.E. IV [Eckenfelder Inc., Nashville, TN (United States)

    1997-05-01

    Despite recent progress in innovative treatment technologies, many problems with contaminated groundwater still require the use of barrier walls, typically in combination with extraction and treatment systems. New technologies for subsurface barrier walls, mostly based on geomembranes, advancements in self-hardening slurries and permeation grouts with materials such as colloidal silica gel and montan wax emulsions, are being developed at an unprecedented pace. The paper discusses deep soil mixing, jet grouting, slurry trenches, and permeation grouting.

  7. Postoperative washing of sutured wounds

    Directory of Open Access Journals (Sweden)

    Conrad Harrison

    2016-11-01

    Full Text Available A best evidence topic was written according to the structured protocol. The three part question addressed was: [In patients undergoing closure of surgical wounds with sutures] does [keeping the wound dry for the first 48 h after closure] [reduce the incidence of surgical site infections (SSIs]? 4 relevant papers were culled from the literature and appraised. The authors, date, country, population, study type, main outcomes, key results and study weaknesses were tabulated. Current NICE guidelines recommend cleaning surgical wounds with sterile saline only for the first 48 h following skin closure. We found no evidence that washing wounds with tap water during this period increases the incidence of SSIs compared to keeping them dry. Further randomised controlled trials will enable the construction of conclusive systematic reviews and meta-analyses.

  8. Wash water waste pretreatment system

    Science.gov (United States)

    1977-01-01

    Investigations were completed on wash waters based on each candidate personal cleansing agent. Evaluations of coagulants, antifoam agents, and the effect of promising antifoams on the chemical precipitation were included. Based on these evaluations two candidate soaps as well as their companion antifoam agents were selected for further work. Operating parameters included the effect of soap concentration, ferric chloride concentration, duration of mixing, and pore size of depth filters on the degree of soap removal. The effect of pressure on water flow through filter cartridges and on the rate of decline of water flow was also investigated. The culmination of the program was the recommendation of a pretreatment concept based on chemical precipitation followed by pressure filtration.

  9. The groundwater subsidy to vegetation: groundwater exchanges between landcover patches

    Science.gov (United States)

    Steven, L. I.; Gimenez, R.; Jobbagy, E. G.

    2015-12-01

    The Gran Chaco is a hot, dry plain, that spans over 60 million hectares across Bolivia, Paraguay, Brazil and Argentina. It supports high biodiversity in its dry forest and savannahs, but is rapidly being converted to agriculture in response to growing soy demand and technology including genetic modification and zero-till, that has made cultivation in drier landscapes more viable. Under natural conditions, the deep-rooted, native vegetation of the Chaco effectively captured all rainfall for evapotranspiration resulting in near zero groundwater recharge under the dry forest. Conversion to shallower rooted soy and corn, combined with the fallow period prior to the growing season, reduces evapotranspiration and allows some water to percolate through the root zone and recharge the groundwater system. When this groundwater recharge occurs, it creates groundwater mounding and a hydraulic gradient that drives flow to adjacent landcover patches where recharge does not occur. As the watertable rises, groundwater becomes available to the deep-rooted, dry forest vegetation. We develop a soil and groundwater flow model to simulate infiltration, percolation, evaporation, rootwater uptake, groundwater recharge and the lateral transfer of water between adjacent landcover patches to quantify this groundwater subsidy from converted agricultural lands to remnant patches of dry forest.

  10. An integrated anaerobic/aerobic bioprocess for the remediation of chlorinated phenol-contaminated soil and groundwater.

    Science.gov (United States)

    Ehlers, George A; Rose, Peter D

    2006-07-01

    An investigation of biodegradation of chlorinated phenol in an anaerobic/aerobic bioprocess environment was made. The reactor configuration used consisted of linked anaerobic and aerobic reactors, which served as a model for a proposed bioremediation strategy. The proposed strategy was studied in two reactors before linkage. In the anaerobic compartment, the transformation of the model contaminant, 2,4,6-trichlorophenol (2,4,6-TCP), to lesser-chlorinated metabolites was shown to occur during reductive dechlorination under sulfate-reducing conditions. The consortium was also shown to desorb and mobilize 2,4,6-TCP in soils. This was followed, in the aerobic compartment, by biodegradation of the pollutant and metabolites, 2,4-dichlorophenol, 4-chlorophenol, and phenol, by immobilized white-rot fungi. The integrated process achieved elimination of the compound by more than 99% through fungal degradation of metabolites produced in the dechlorination stage. pH correction to the anaerobic reactor was found to be necessary because acidic effluent from the fungal reactor inhibited sulfate reduction and dechlorination.

  11. EFRT M-12 Issue Resolution: Solids Washing

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, David L.; Schonewill, Philip P.; Toth, James J.; Huckaby, James L.; Eslinger, Paul W.; Hanson, Brady D.; Kurath, Dean E.; Minette, Michael J.

    2009-08-14

    Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed, and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes.” The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. Two operating scenarios were evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching pe