Author: R. Brent Nielsen
Publisher:
ISBN:
Category : Bioremediation
Languages : en
Pages : 66

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Book Description

Author:
Publisher:
ISBN:
Category : Chlorohydrocarbons
Languages : en
Pages : 104

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Book Description

Author: Robert D. Norris
Publisher: DIANE Publishing
ISBN: 9780788122507
Category :
Languages : en
Pages : 264

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Book Description
Provides a detailed background of the technologies available for the bioremediation of contaminated soil & ground water. Prepared for scientists, consultants, regulatory personnel, & others who are associated in some way with the restoration of soil & ground water at hazardous waste sites. Also provides insights to emerging technologies which are at the research level of formation, ranging from theoretical concepts, through bench scale inquiries, to limited field-scale investigations. 95 tables & figures.

Author: Annamarie F. Therrien
Publisher:
ISBN:
Category : Biogeochemistry
Languages : en
Pages : 77

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Book Description
Constructed wetlands are an efficient and cost effective means for chlorinated aliphatic hydrocarbon remediation, and will therefore continue to gain momentum as an accepted treatment by the US EPA (U.S. EPA, 1995; Amarante, 2000; Lien, 2001; WETPOL, 2009). The treatment options for chlorinated aliphatic hydrocarbons (CAHs), including wetlands, capitalize on aerobic/anaerobic interfaces in which bacterially mediated reduction-oxidation reactions degrade pollutants (Li, 1997; Bradley, 1998; Lorah and Voytek, 2004; Amon, 2007; Imfeld, 2008). In August 2000, researchers at Wright State University (WSU) combined efforts with the United States Air Force Institute of Technology (AFIT) to construct a pilot-scale upward-flow treatment wetland on Wright-Patterson Air Force Base with parameters that could remediate perchloroethene (PCE) found in a nearby aquifer (Amon et al., 2007). Eleven studies of short duration have since documented the existance of anerobic and aerobic interfaces by measuring various terminal electron acceptors (sulfate, nitrate, methane, iron) and numerous other parameters. The studies evaluated PCE degradation rates, geochemical profiles, hydraulic conductivity and chlorinated ethene concentrations. (Bugg, 2002; Opperman, 2002; Clemmer, 2003; Kovacic, 2003; BonDurant, 2004; Sobolewski, 2004; Lach, 2004; Schlater, 2006; Mohamud, 2007; Waldron, 2007, Corbin, 2008). The present research has attempted to compile, organize, and re-analyze the data collected by AFIT and WSU researchers during 2001-2006. Data was analyzed using Jenks Optimization (goodness of variance fit) method to identify and remove outliers. Meta analysis of CAH concentrations and redox parameters was performed by creating data subsets of individual piezometer and depths, influent to effluent transect data and ArcGIS maps. The present analysis concludes that a fully functioning wetland with strongly reducing geochemical conditions and flow patterns capable of PCE destruction developed at this site within 18-24 months. Dechlorination of CAHs was observed at every depth and at 63 of 66 sampled locations despite significant differences in hydraulic conductivity and available electron acceptors. Rate of dechlorination varied with depth and hydraulic conductivity. Strongest reducing conditions developed at Middle layer (0.69 m) and demonstrated the highest rates of PCE dechlorination. Maximum degradation of vinyl chloride (VC) and 1,2 dichloroethenes (DCE) occurred in Upper layer (0.23m) where conditions may have been more oxidizing. The size of the pilot-scale treatment wetland generally allowed adequate residence time despite short circuits. However, two exceptions were observed: (i) near the effluent, increases in head pressure, due to laminar flow bring higher concentrations from gravel layer to surface quickly, and (ii) CAHs re transmitted quickly along the wetland’s outer boundary, possibly along the soil-PVC liner. Despite these effects, with the exception of one researcher’s results, the effluent concentrations for all CAH species remained below their respective MCLs after January 2003. The study suggests that the construction of wetland for the treatment PCE-contaminated groundwater include establishing and employing a grid monitoring system to ascertain geographical boundaries for problem areas, frequent sampling in initial 24 months and establishing controls on influent pumping system to adjust residence time as needed.

Author: Victor Magar
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 408

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Book Description
The symposium included 600 presentations in 50 sessions on bioremediation and supporting technologies used for a wide range of contaminants already in, or poised to invade, soil, groundwater, and sediment. Three hundred and fifty-two papers were selected and organized into ten volumes. Volume seven's articles examine the use of enhanced anaerobic biotransformation processes for treatment of chlorinated solvents in soil and groundwater. Electron donors used to stimulate reductive dechlorination processes in lab- and field-scale demonstrations are also presented. Articles average eight pages, and contain abstracts and references. Annotation copyrighted by Book News Inc., Portland, OR.

Author: Battelle Memorial In
Publisher: CRC Press
ISBN: 9780873719834
Category : Science
Languages : en
Pages : 548

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Book Description
This timely reference presents the state of the art of the emerging and rapidly changing field of bioremediation of chlorinated solvents, PCBs, and other chlorinated compounds, as well as PAHs, both in situ and on site. This landmark publication reports significant advances in bioremediation, with an emphasis on practical applications and state-of-the-art developments. Laboratory and field-oriented reviews are presented with the objective of tying treatability studies and recent laboratory developments to field applications. No other reference source gives you access to the most current techniques and methods for the bioremediation of chlorinated and polycyclic aromatic hydrocarbon compounds. This book represents the work of leading experts in the fields of in situ and on-site bioremediation from North America, Europe, and Asia. The chapters include current field applications and laboratory studies undertaken, in some cases, in countries with regulatory standards more stringent than those of the United States.

Author: Bruce C. Alleman
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 424

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Book Description
Natural attenuation was first demonstrated at sites with hydrocarbon contamination, but recent studies at sites contaminated by chlorinated compounds have shown that this approach often has merit for these more challenging contamination problems. This volume covers natural attenuation in media ranging from deep aquifers to shallow soils, and for contaminants ranging from fuels to solvents to herbicides, and offers the reader a comprehensive overview of case studies that represent the state of the art in natural attenuation approaches to site remediation.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 457

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Book Description
The Department of Defense (DoD) has identified hundreds of sites where groundwater is contaminated with chlorinated solvents; these represent one of the DoD's largest remediation liabilities. In addition to their use in many industrial processes, chlorinated solvents have historically been used for cleaning and degreasing such diverse products as aircraft engines, automobile parts, electronic components, and clothing in the military and commercial sectors. Chlorinated solvents were often released to the subsurface environment in waste water or in the form of dense non-aqueous phase liquids (DNAPLs). As a result of their physical and chemical properties, DNAPLs are difficult to remediate once they have migrated into groundwater aquifers. Enhanced in situ anaerobic bioremediation can be an effective method of degrading various chlorinated solvents dissolved in groundwater, including chloroethenes, chloroethanes, and chloromethanes. Collectively, these compounds (some of which are degradation products of chlorinated solvents) are referred to as chlorinated aliphatic hydrocarbons (CAHs). Advantages of enhanced anaerobic bioremediation include complete mineralization of the contaminants in situ with little impact on infrastructure and relatively low cost compared to more active engineered remedial systems.

Author:
Publisher: Government Institutes
ISBN:
Category : Nature
Languages : en
Pages : 262

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Book Description

Author: Commission on Geosciences, Environment, and Resources
Publisher: National Academies Press
ISBN: 0309069327
Category : Science
Languages : en
Pages : 289

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Book Description
In the past decade, officials responsible for clean-up of contaminated groundwater have increasingly turned to natural attenuation-essentially allowing naturally occurring processes to reduce the toxic potential of contaminants-versus engineered solutions. This saves both money and headaches. To the people in surrounding communities, though, it can appear that clean-up officials are simply walking away from contaminated sites. When is natural attenuation the appropriate approach to a clean-up? This book presents the consensus of a diverse committee, informed by the views of researchers, regulators, and community activists. The committee reviews the likely effectiveness of natural attenuation with different classes of contaminants-and describes how to evaluate the "footprints" of natural attenuation at a site to determine whether natural processes will provide adequate clean-up. Included are recommendations for regulatory change. The committee emphasizes the importance of the public's belief and attitudes toward remediation and provides guidance on involving community stakeholders throughout the clean-up process. The book explores how contamination occurs, explaining concepts and terms, and includes case studies from the Hanford nuclear site, military bases, as well as other sites. It provides historical background and important data on clean-up processes and goes on to offer critical reviews of 14 published protocols for evaluating natural attenuation.