Download or read book Zero Valent Iron Permeable Reactive Barriers written by and published by . This book was released on 2001 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report briefly reviews issues regarding the implementation of the zero-valent iron permeable reactive barrier (PRB) technology at sites managed by the U.S. Department of Energy (DOE). Initially, the PRB technology, using zero-valent iron for the reactive media, was received with great enthusiasm, and DOE invested millions of dollars testing and implementing PRBs. Recently, a negative perception of the technology has been building. This perception is based on the failure of some deployments to satisfy goals for treatment and operating expenses. The purpose of this report, therefore, is to suggest reasons for the problems that have been encountered and to recommend whether DOE should invest in additional research and deployments. The principal conclusion of this review is that the most significant problems have been the result of insufficient characterization, which resulted in poor engineering implementation. Although there are legitimate concerns regarding the longevity of the reactive media, the ability of zero-valent iron to reduce certain chlorinated hydrocarbons and to immobilize certain metals and radionuclides is well documented. The primary problem encountered at some DOE full-scale deployments has been an inadequate assessment of site hydrology, which resulted in misapplication of the technology. The result is PRBs with higher than expected flow velocities and/or incomplete plume capture. A review of the literature reveals that cautions regarding subsurface heterogeneity were published several years prior to the full-scale implementations. Nevertheless, design and construction have typically been undertaken as if the subsurface was homogeneous. More recently published literature has demonstrated that hydraulic heterogeneity can cause so much uncertainty in performance that use of a passive PRB is precluded. Thus, the primary conclusion of this review is that more attention must be given to site-specific issues. Indeed, the use of a passive PRB requires an unusually comprehensive hydrologic characterization so that the design can be based on a thorough understanding of subsurface heterogeneity rather than on average values for hydraulic parameters. Scientists and engineers are capable of conducting the level of investigation required. However, design costs will increase, and the pre-design field work may demonstrate that a passive PRB is not suitable for a particular site. In such cases, an option to consider is hydraulic augmentation, such as pumping (in which the system is no longer passive) or gravity flow from drains. In these circumstances, operation of the treatment media is under known hydraulic conditions. These systems typically contain the treatment media in a vault or in drums. Most of the media problems in such systems have been related to the exclusion of air and can be addressed by better engineering design or by frequent maintenance. Finally, a number of outstanding issues require resolution for further application of this technology. Of particular interest to DOE is resolving the removal mechanisms for uranium and technetium. Few data are available for the latter, and for the former, the technical literature is contradictory. Determining the mechanisms has long-term cost implications; engineers must consider whether it is appropriate to remove or simply abandon a barrier that is no longer functioning. Other issues that are unresolved include determining how hydraulic performance is affected by the emplacement method and quantifying the effects of varying groundwater types on barrier longevity.
Download or read book The Long term Viability of a Zero valent Iron Permeable Reactive Barrier written by Stuart Cowburn and published by . This book was released on 2000 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Permeable Reactive Barriers written by Genevieve A. Boshoff and published by . This book was released on 2005 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Long term Performance of Permeable Reactive Barriers Using Zero valent Iron written by Richard T. Wilkin and published by . This book was released on 2002 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research described in this research brief explores the geochemical and microbiological processes occurring within zero-valent iron treatment zones in permeable reactive barriers that may contribute to decreases in iron reactivity and decreases in reaction zone permeability that, in turn, may eventually lead to system plugging and failure. Using advanced surface analytical techniques together with detailed coring and water sampling programs at two geographically, hydrogeologically, and geochemically distinct iron barrier installation sites, specific objectives of this research project were to: 1) Characterize the type and nature of surface precipitates forming over time at the upgradient aquifer/iron interface, within the iron zone, and at the downgradient/iron interface. 2) Develop conceptual models that predict the type and rate of precipitate formation based on iron characteristics and water chemistry. 3) Identify type and extent of microbiological activity upgradient, within and downgradient in at least one of the chosen sites to evaluate microbiological response or effects from emplaced iron into an aquifer system. 4) Develop practical and cost-effective protocols for long-term performance assessments at permeable reactive barrier installations.
Download or read book Low Frequency Electrical Properties of Zero Valent Iron Implications for Performance Monitoring of Permeable Reactive Barriers PRBs written by Yuxin Wu and published by . This book was released on 2007 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: The permeable reactive barrier is an in-situ remediation technology for groundwater contaminants. Long term performance monitoring of PRB is critical to the estimation of barrier efficiency.
Download or read book Remediation of Explosives in Groundwater Using a Zero Valent Iron Permeable Reactive Barrier written by and published by . This book was released on 2008 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: This final technical report documents the demonstration of a zero-valent iron (ZVI) permeable reactive barrier (PRB) for the removal of explosives from groundwater. The demonstration was conducted at the Cornhusker Army Ammunition Plant (CAAP) near Grand Island, Nebraska. The primary objective of this project was to evaluate the cost and performance of the ZVI PRB Performance of the PRB was evaluated by monitoring groundwater concentrations of explosives downgradient of the PRB. Data obtained during the demonstration were used to assess the costeffectiveness of this approach for long-term removal of explosives from groundwater. The primary advantages of ZVI PRBs for groundwater remediation are: 1. No aboveground remediation equipment is required 2. Rapid conversion of groundwater to reducing conditions 3. Low operation and maintenance costs 4. Long-lasting (>20 years) in situ treatment 5. Cost-effective. The cost-effective use of ZVI PRBs may be limited by the depth to groundwater and the ability to install the PRB in some geologic media. However, at sites without these physical constraints, the approach can be highly effective.
Download or read book Permeable Barriers for Groundwater Remediation written by Arun R. Gavaskar and published by . This book was released on 1998 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Because of the limitations of conventional pump-and-treat systems in treating groundwater contaminants, permeable barriers are potentially more cost-effective than pump-and-treat systems for treating dissolved chlorinated solvent plumes, which may persist in the saturated zone for several decades. Other contaminants, such as chromium or other soluble heavy metals, can also be treated with this technology. Permeable Barriers for Groundwater Remediation discusses the types of permeable barriers, their design and construction, and how they can be monitored to evaluate compliance. It provides practical guidance on reactive media selection, treatability testing, hydrogeologic and geochemical modeling, and innovative installation techniques for the evaluation and application of this promising new technology. The types of permeable barriers discussed include: trench-type and caisson-based reactive cells; innovative emplacements, such as horizontal trenching and jetting; and continuous reactive barriers versus funnel-and-gate systems.
Download or read book Handbook of Groundwater Remediation using Permeable Reactive Barriers written by David Naftz and published by Academic Press. This book was released on 2002-10-17 with total page 569 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last century and a half, groundwaters have become contaminated by a growing number of organic and inorganic substances ranging from petroleum-derived hydrocarbons to radioactive compounds, to cancer-causing hexavalent chromium. The importance of uncontaminated groundwater for agriculture, human consumption, and the environmental health of ecosystems is paramount to the health and productivity of industrial society. Water scientists and managers are focused on developing cost-effective methods to reverse this trend.Several methodologies have been developed, however few are as cost-effective as the use of readily available materials, such as iron and organic compost, for absorbing and isolating contaminants within the matrix of a permeable barrier. The Handbook of Groundwater Remediation using Permeable Reactive Barriers presents readers with this latest technology and developments within four main sections:1. Innovations in Design, Construction, and Evaluation of PRBs2. Development of Reactive Materials3. Evaluations of Chemical and Biological Processes4. Case Studies of Permeable Reactive Barrier InstallationsThe Handbook is one of the first references specifically on this topic. It is an excellent fit for graduate students entering this emerging field as well as professionals conducting research or implementing this technology.
Download or read book Field Applications of in Situ Remediation Technologies written by and published by DIANE Publishing. This book was released on 1999 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Long Term Performance of Permeable Reactive Barriers written by K.E. Roehl and published by Gulf Professional Publishing. This book was released on 2005-04-27 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt: While extensive research has been performed on many technological aspects of permeable reactive barriers and a number of contaminants have so far been successfully treated by PRB systems, long-term performance has not been extensively considered and little is known about the processes influencing long-term behaviour. This gap in our knowledge is all the more disadvantageous as design life has a decisive influence on the economic viability of PRBs. The book describes methods for evaluation and enhancement of the long-term performance of PRB systems, especially of those targeting heavy metals, specifically uranium, and organic contaminants by sorption and/or precipitation mechanisms. Major topics in the book are: Selection and characterisation of suitable reactive materials Characterisation of the relevant contaminant attenuation processes Developing new contaminant-binding chemical compounds ("ligands") Accelerated testing methods to assess the long-term performance of the attenuation mechanisms in PRBs Evaluation of the influence of site characteristics on PRB performance Monitoring of existing and new field installations Coupling of electrokinetic techniques and PRB systems Large-scale laboratory and field tests and their results It addresses the long-term performance of PRBs, an important feature of this novel remediation technology, systematically. It deals extensively with heavy metal removal, with special emphasis on uranium. A number of case studies, experiences with large-scale modelling and test site experiments provide insight into the practical application of the results. This volume will contribute to the science underpinning groundwater remediation, and this will result in the improvement of quality of life and health and safety. * A systematic approach to investigating the long-term performance of permeable reactive barriers * Development of new contaminant-binding chemical compounds ("ligands"), accelerated testing methods to assess the long-term performance, and efficiency enhancing electrokinetic techniques * Extensive data and information on a Hungarian uranium mining facility; once a carefully kept secret of the Soviet Union
Download or read book Groundwater Geochemistry written by Sughosh Madhav and published by John Wiley & Sons. This book was released on 2021-06-14 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains both practical and theoretical aspects of groundwater resources relating to geochemistry. Focusing on recent research in groundwater resources, this book helps readers to understand the hydrogeochemistry of groundwater resources. Dealing primarily with the sources of ions in groundwater, the book describes geogenic and anthropogenic input of ions into water. Different organic, inorganic and emerging contamination and salinity problems are described, along with pollution-related issues affecting groundwater. New trends in groundwater contamination remediation measures are included, which will be particularly useful to researchers working in the field of water conservation. The book also contains diverse groundwater modelling examples, enabling a better understanding of water-related issues and their management. Groundwater Geochemistry: Pollution and Remediation offers the reader: An understanding of the quantitative and qualitative challenges of groundwater resources An introduction to the environmental geochemistry of groundwater resources A survey of groundwater pollution-related issues Recent trends in groundwater conservation and remediation Mathematical and statistical modeling related to groundwater resources Students, lecturers and researchers working in the fields of hydrogeochemistry, water pollution and groundwater will find Groundwater Geochemistry an essential companion.
Download or read book Quantification of Morphological Changes in Zero Valent Iron ZVI written by Ping Luo and published by . This book was released on 2009 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laboratory and Numerical Investigation of Implementing Temperature Control on Zero valent Iron Permeable Reactive Barriers for Treating Trichlorethene contaminated Groundwater written by Farshid Fatemi and published by . This book was released on 2008 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Permeable Reactive Barrier written by Ravi Naidu and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Remediation of ground water is complex and often challenging. The passive remediation technology, currently in vogue, is based on permeable reactive barriers (PRB) that allow water to pass through while the fence/barrier made of reactive materials remediates the contaminants. Although PRB has been in operation for over a decade there are limited published books available. This book covers in one single volume all the information needed to plan, design/model and apply a successful, cost-effective and sustainable PRB technology.
Download or read book Capstone report on the application monitoring and performance of permeable reactive barriers for groundwater remediation Volume 1 Performance evaluations at two sites written by and published by DIANE Publishing. This book was released on 2003 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Permeable Reactive Barrier Technology written by P. D'Andrea and published by . This book was released on 2002 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Permeable Reactive Barrier Performance written by and published by . This book was released on 2002 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Permeable reactive barriers (PRB) are developing into an entire new class of technologies for groundwater remediation. A permeable barrier is a porous "barrier" that is placed in the path of a groundwater plume, in various configurations. The barrier, or at least the permeable portion of the barrier, contains a reactive or adsorptive medium that helps remove the contaminants from the plume, as the groundwater flows through the barrier. The primary advantage of permeable barriers is their passive operation and the resulting potential for long-term cost savings. The technology emerged in the mid-1990s with the use of granular zero-valent iron as a reactive medium for treatment of groundwater contaminated with chlorinated volatile organic compounds (CVOCs), such as trichloroethylene (TCE) and perchloroethylene (PCE). More recently, there is interest in developing other treatment media and methods of construction to address a broader variety of contaminants and sites.
