Chlorinated ethenes (CEs) are widespread ground water contaminants, apparently due to their extensive migration from numerous contamination source points. In this study, a long-term field investigation and aquifer microcosm experiments were combined to evaluate the effectiveness of electron donor materials used to create and maintain subsurface permeable reactive barriers (PRBs) for the enhanced in-situ biodegradation of CEs. The laboratory component includes the first side-by-side comparison of electron donor materials dairy whey, lactate syrup, and Hydrogen Release Compound [Registered] (HRC), in which dechlorination rates, fermentation product distributions, and H[subscript 2] production were monitored as measures of substrate efficiency. Field study allowed the first investigation of the long-term efficacy of a full-scale (~300 ft.) when PRB designed to dechlorinate high concentrations of CEs (10[superscript 2]-10[superscript 3] [micro]g/L) migrating from a source zone. The effects of altering substrate loading volume, loading frequency, and injection method on CE distributions are examined. In donor-amended aquifer microcosms, substrate fermentation to slow-degrading organic acids maintained low H[subscript 2] partial pressures that, as previous studies suggest, may give competitive advantage to dechlorinators over hydrogenotrophic methanogens. Whey-amended and lactate-amended microcosms exhibited faster complete dechlorination. Whey-amended microcosms contained the highest percentage of organic acid carbon upon complete dechlorination. Whey's efficiency improved in microcosms prepared with whey-treatment-zone sediment and ground water, due apparently to the growth of native dechlorinators (e.g. Dehalococcoides) and microbial adaptation to whey within the PRB. In the field study, CEs decreased to low ([less than or equal to]10 [micro]g/L) or undetected levels within the PRB, while trichloroethene and cis-dichloroethene treatment-period average concentrations decreased significantly at downgradient points. Improved and sustained dechlorination was observed following injection of 300 kg whey, as a 750 mg/L slurry, with the use of extraction-injection loops. Results indicate whey loading values of 0.2 kg/m[superscript 3] are appropriate under sufficiently reducing conditions. Comparison of whey fermentation product, chemical oxygen demand (COD), and CE trends indicate whey's lifetime was 4-5 months. Based on the longevity of whey and its 2006 average market price, the estimated material cost of a 300-ft whey PRB is $700/year. Cost comparison, based on determinations of carbon flow in donor-amended microcosms, suggests whey is by far the more cost-efficient PRB material.

This book presents a comprehensive, up-to-date review of technologies for cleaning up contaminants in groundwater and soil. It provides a special focus on three classes of contaminants that have proven very difficult to treat once released to the subsurface: metals, radionuclides, and dense nonaqueous-phase liquids such as chlorinated solvents. Groundwater and Soil Cleanup was commissioned by the Department of Energy (DOE) as part of its program to clean up contamination in the nuclear weapons production complex. In addition to a review of remediation technologies, the book describes new trends in regulation of contaminated sites and assesses DOE's program for developing new subsurface cleanup technologies.

​This volume provides a review of the past 10 to 15 years of intensive research, development and demonstrations that have been on the forefront of developing bioaugmentation into a viable remedial technology. This volume provides both a primer on the basic microbial processes involved in bioaugmentation, as well as a thorough summary of the methodology for implementing the technology. This reference volume will serve as a valuable resource for environmental remediation professionals who seek to understand, evaluate, and implement bioaugmentation.

At hundreds of thousands of commercial, industrial, and military sites across the country, subsurface materials including groundwater are contaminated with chemical waste. The last decade has seen growing interest in using aggressive source remediation technologies to remove contaminants from the subsurface, but there is limited understanding of (1) the effectiveness of these technologies and (2) the overall effect of mass removal on groundwater quality. This report reviews the suite of technologies available for source remediation and their ability to reach a variety of cleanup goals, from meeting regulatory standards for groundwater to reducing costs. The report proposes elements of a protocol for accomplishing source remediation that should enable project managers to decide whether and how to pursue source remediation at their sites.

In the late 1970s and early 1980s, our nation began to grapple with the legacy of past disposal practices for toxic chemicals. With the passage in 1980 of the Comprehensive Envir- mental Response, Compensation, and Liability Act (CERCLA), commonly known as Sup- fund, it became the law of the land to remediate these sites. The U. S. Department of Defense (DoD), the nation’s largest industrial organization, also recognized that it too had a legacy of contaminated sites. Historic operations at Army, Navy, Air Force, and Marine Corps facilities, ranges, manufacturing sites, shipyards, and depots had resulted in widespread contamination of soil, groundwater, and sediment. While Superfund began in 1980 to focus on remediation of heavily contaminated sites largely abandoned or neglected by the private sector, the DoD had already initiated its Installation Restoration Program in the mid-1970s. In 1984, the DoD began the Defense Environmental Restoration Program (DERP) for contaminated site assessment and remediation. Two years later, the U. S. Congress codified the DERP and directed the Secretary of Defense to carry out a concurrent program of research, development, and demonstration of innovative remediation technologies. As chronicled in the 1994 National Research Council report, “Ranking Hazardous-Waste Sites for Remedial Action,” our early estimates on the cost and suitability of existing techn- ogies for cleaning up contaminated sites were wildly optimistic. Original estimates, in 1980, projected an average Superfund cleanup cost of a mere $3.

Across the United States, thousands of hazardous waste sites are contaminated with chemicals that prevent the underlying groundwater from meeting drinking water standards. These include Superfund sites and other facilities that handle and dispose of hazardous waste, active and inactive dry cleaners, and leaking underground storage tanks; many are at federal facilities such as military installations. While many sites have been closed over the past 30 years through cleanup programs run by the U.S. Department of Defense, the U.S. EPA, and other state and federal agencies, the remaining caseload is much more difficult to address because the nature of the contamination and subsurface conditions make it difficult to achieve drinking water standards in the affected groundwater. Alternatives for Managing the Nation's Complex Contaminated Groundwater Sites estimates that at least 126,000 sites across the U.S. still have contaminated groundwater, and their closure is expected to cost at least $110 billion to $127 billion. About 10 percent of these sites are considered "complex," meaning restoration is unlikely to be achieved in the next 50 to 100 years due to technological limitations. At sites where contaminant concentrations have plateaued at levels above cleanup goals despite active efforts, the report recommends evaluating whether the sites should transition to long-term management, where risks would be monitored and harmful exposures prevented, but at reduced costs.

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.