Hanford remediation at 20 years: A glass half‐empty

The U.S. Department of Energy's (US DOE's) responsibilities for its former national nuclear weapons complex include remediation of the Hanford Site in Washington State. In 1989, the site's primary mission shifted from nuclear weapons material production to cleanup of the extensive radioactive and chemical contamination that represented the production legacy. Cleanup is governed by the Tri‐Party Agreement (TPA), between the US DOE, as responsible party, and the U.S. Environmental Protection Agency and Washington State Department of Ecology, as joint regulators. Nearly 20 years have passed since the TPA was signed, but the Hanford remediation is expected to require decades longer. This article covers the cleanup progress to date and challenges that remain, particularly from millions of gallons of highly radioactive liquid wastes and proposals to bring new wastes to Hanford. © 2008 Wiley Periodicals, Inc.     

Remediation,land use,and risk at Rocky Flats,and a comparison with Hanford

US Department of Energy (US DOE) responsibilities for its former national atomic weapons complex include remediation of the Rocky Flats facility near Denver, Colorado. In 1993, the site's primary mission shifted from “production'' of plutonium components for atomic weapons to cleanup of extensive radioactive and chemical contamination representing the legacy of production activities. Remediation was governed by the agreements between the US DOE as the responsible party and the US Environmental Protection Agency and the state of Colorado as joint regulators. In 1995, the Rocky Flats Future Use Working Group issued its final report, recommending among other features that long‐term cleanup reduce contamination levels to background. This article describes the circumstances that led the US DOE to complete the Rocky Flats cleanup more quickly and makes comparisons to the situation at the US DOE's Hanford site. © 2011 Wiley Periodicals, Inc.     

Remediation,land use,and risk at Hanford

U.S. Department of Energy (US DOE) remediation responsibilities include the Hanford site in Washington State. Cleanup is governed by the Tri‐Party Agreement (TPA) between the US DOE as the responsible party and the U.S. Environmental Protection Agency and Washington State Department of Ecology as joint regulators. In 2003, the US DOE desired to implement a “Risk‐Based End State” (RBES) policy at Hanford, with remediation measures driven by acceptable risk standards using exposure scenarios based on the 1999 Hanford Comprehensive Land‐Use Plan. Facing resistance from regulators and stakeholders, the US DOE solicited public input on its policy. This led to a Hanford Site End State Vision in 2005 and a commitment that the TPA would continue to control remediation. This article describes how regulator and public participation modified RBES to an end‐state vision. © 2010 Wiley Periodicals, Inc.     

Evaluation of a vertical frozen soil barrier at oak ridge national laboratory

Arctic Foundations, Inc. (AFI), of Anchorage, Alaska, has developed a freeze barrier system designed to hydraulically isolate a contaminant source area. The system can be used for long‐term or temporary containment of groundwater until appropriate remediation techniques can be applied. The technology was evaluated under the United States Environmental Protection Agency's (EPA's) Superfund Innovative Technology Evaluation (SITE) program at the United States Department of Energy's (DOE's) Oak Ridge National Laboratory (ORNL) facility in Oak Ridge, Tennessee. For the demonstration, an array of freeze pipes called “thermoprobes” was installed to a depth of 30 feet below ground surface around a former waste collection pond and keyed into bedrock. The system was used to establish an impermeable frozen soil barrier to hydraulically isolate the pond. Demonstration personnel collected independent data to evaluate the technology's performance. A variety of evaluation tools were used—including a groundwater dye tracing investigation, groundwater elevation measurements, and subsurface soil temperature data—to determine the effectiveness of the freeze barrier system in preventing horizontal groundwater flow beyond the limits of the frozen soil barrier. Data collected during the demonstration provided evidence that the frozen soil barrier was effective in hydraulically isolating the pond.     

Rocky Flats,plutonium, and controversy: Citizen activists provide institutional memory

The U.S. Atomic Energy Commission (AEC) selected Rocky Flats, east of the Rocky Mountains, as the site to fabricate “plutonium pits,” triggers for H‐bombs, and operations began in 1952. Press reports revealed the plant's connection to atomic weapons in 1956. Denver is downwind and “downslope” by about 16 miles. As western suburbs moved closer to Rocky Flats over time, plant accidents sent plutonium and other contaminants offsite. In 1989, armed agents of the U.S. Environmental Protection Agency (EPA) and Federal Bureau of Investigation raided the facility, and the plant operator, Rockwell International, subsequently pleaded guilty to criminal environmental violations. By this time, the U.S. Department of Energy had inherited responsibility for Rocky Flats and atomic weapons production. In 1993, the primary mission at Rocky Flats became cleanup of contamination from plutonium and other hazardous substances. Under Energy's “Accelerated Cleanup” plan, remediation was certified complete in 2005 by the Department's cleanup regulators, EPA, and the Colorado Department of Public Health. But planned uses for the “buffer zone” around the facility's central industrial area, and for off‐site areas continued to generate public controversy. This article examines the controversy and reports on general “stewardship” concepts for long‐term waste management.     

Transuranic waste remediation in Idaho: Pit 9, failed contracts,and lawsuits

The U.S. Department of Energy (US DOE) remediation responsibilities include its Idaho National Laboratory. In 1989, the U.S. Environmental Protection Agency placed the Idaho site on its National Priority List for environmental cleanup. The site's contamination legacy from operations included inactive reactors and other structures, spent nuclear fuel, high‐level liquid radioactive wastes, calcined radioactive wastes, and transuranic wastes. Documents governing cleanup include a 1995 Settlement Agreement between the US DOE and the US Navy as responsible parties, and the State of Idaho. The Subsurface Disposal Area contains buried transuranic wastes, lies above the East Snake River Plain Aquifer, and could be the “site's most nettlesome cleanup issue,” according to an outside observer. This article describes the technical and legal difficulties that have been encountered in remediating this area. © 2010 Wiley Periodicals, Inc.     

Demonstration of MicroBlower™ technology for sustainable soil vapor extraction: Case studies at the Savannah River Site,South Carolina

The MicroBlower Sustainable Soil Vapor Extraction System is a cost‐effective device specifically designed for remediation of organic compounds in the vadose zone. The system is applicable for remediating sites with low levels of contamination and for transitioning sites from active source technologies such as active soil vapor extraction to natural attenuation. It can also be a better choice for remediating small source zones that are often found in “tight zones” that are controlled by diffusion rate. The MicroBlower was developed by the Savannah River National Laboratory at the US Department of Energy's Savannah River Site to address residual volatile organic compound (VOC) contamination after shutdown of active soil vapor extraction systems. In addition, the system has been deployed to control recalcitrant sources that are controlled by diffusion rates. © 2012 Wiley Periodicals, Inc.     

Rethinking groundwater monitoring at the Hanford Site

Groundwater monitoring at Department of Energy's (DOE's) Hanford Site is a large, expensive undertaking serving multiple purposes, including compliance with regulations and DOE orders, remediation efforts under CERCLA, and sitewide risk evaluations. Like most large Federal facilities, the monitoring program currently in place has evolved and grown overtime as new requirements were established and groups were assigned to address them. DOE and its regulators simultaneously awakened to the fact that there was a need to reevaluate the monitoring activities at Hanford, to better integrate the program, to avoid duplicative sampling, to improve everyone's understanding of the performance of the network, and to evaluate whether adequate data could be collected for lower cost. This paper describes the approch that was developed to guide the rethinking effort with direct and extensive involvement of DOE, EPA, Washington Department of Ecology, Indian Tribes, and DOE Contractors, and how this approach was applied to a large portion of the site. Both the human element of the process (cultural change), as well as some of the technical details associated with the effort, including a flexible application of EPA's data quality objectives process, are discussed.     

SITE Program Success: Cost Savings to Government and Increased Revenue for Technology Vendors

The Superfund Innovative Technology Evaluation (SITE) program is a program mandated by Congress through the 1986 Superfund Amendments and Reauthorization Act (SARA). The original Superfund allowed no provisions for research and development of needed remediation technologies. Problems arose when the demand for involved, complex treatment could not be met by the traditional contain, haul, and dispose process that hazardous waste handlers had become familiar with. In response to the increasing complexity of hazardous waste site remediation, SARA called for an “Alternative or Innovative Treatment Technology Research and Demonstration Program.” As a result, EPA's Office of Solid Waste and Emergency Response and the Office of Research and Development established the SITE program. This article is a historical analysis of the unique cost savings of the SITE program.     

Formerly utilized sites remedial action program “completed” sites: Lessons for long‐term stewardship

The Formerly Utilized Sites Remedial Action Program (FUSRAP) covers inactive commercial, federal, and university facilities that once supported activities of the Manhattan Project or Atomic Energy Commission. Current responsibilities, established by a Memorandum of Understanding (MOU), are split between the U.S. Department of Energy (US DOE) and the U.S. Army Corps of Engineers. The MOU distinguishes between facilities remediated before 1997 (“completed” sites) and those where remediation remained to be completed at that time. This article evaluates activities conducted at completed sites with regard to considerations for long‐term stewardship, which is defined by the US DOE as all activities necessary to protect human health and the environment after remediation is considered complete. Experience with these FUSRAP sites provides “lessons learned” for the requirements of satisfactory long‐term stewardship. © 2007 Wiley Periodicals, Inc.     

A Cost Comparison of Organic versus Inorganic Ion Exchange Resin for Remediation of High-Level Waste

Ion exchange (IX) can be used to aid in the remediation of underground storage tank (UST) radioactive waste at the U.S. Department of Energy's Hanford site in the state of Washington. In particular, IX can be used to concentrate the radionuclides in liquid-based waste prior to immobilization for final disposal. Concentration of the radionuclides can significantly reduce the final immobilized high-level waste volume and consequent overall remediation cost. Organic and inorganic IX resins each have unique advantages and disadvantages regarding the remediation process. This study presents a comparison of the remediation cost for UST waste at Hanford for a phenol-formaldehyde type organic resin versus crystalline silico-titanate inorganic resin. It was determined that with optimum processing conditions such as waste blending and sludge washing, remediation with the inorganic resin would be less expensive than the organic resin. Assuming baseline remediation conditions, the use of inorganic rather than organic IX resin for UST remediation at Hanford can save approximately $383 million. A limited sensitivity analysis was performed as pan of this study and is reported in the following. © 1999 John Wiley & Sons, Inc.     

In-situ bioremediation of hanford groundwater

The U.S. Department of Energy has generated liquid wastes containing radioactive and hazardous chemicals throughout the more than forty years of operation at its Hanford site in Washington State. Many of the waste components, including nitrate and carbon tetrachloride (CCl₄), have been detected in the Hanford groundwater. In-situ bioremediation of CCl₄ and nitrate is being considered to clean the aquifer. Preliminary estimates indicate that this technology should cost significantly less than ex-situ bioremediation and about the same as air stripping/granular activated carbon. In-situ bioremediation has the advantage of providing ultimate destruction of the contaminant and requires significantly less remediation time. Currently, a test site is under development. A computer-aided design tool is being used to design optimal remediation conditions by linking subsurface transport predictions, site characterization data, and microbial growth and contaminant destruction kinetics.     

Treatment technologies for 1,4‐Dioxane: Fundamentals and field applications

1,4‐Dioxane is a synthetic industrial chemical frequently found at contaminated sites where 1,1,1‐trichloroethane was used for degreasing. It is a probable human carcinogen and has been found in groundwater at sites throughout the United States. The physical and chemical properties and behavior of 1,4‐dioxane create challenges for its characterization and treatment. It is highly mobile and has not been shown to readily biodegrade in the environment. In December 2006, the U.S. Environmental Protection Agency's Office of Superfund Remediation and Technology Innovation (OSRTI) prepared a report titled “Treatment Technologies for 1,4‐Dioxane: Fundamentals and Field Applications.” The report provides information about the chemistry of dioxane, cleanup goals, analytical methods, available treatment technologies, and site‐specific treatment performance data. The information may be useful to project managers, technology providers, consulting engineers, and members of academia faced with addressing dioxane at cleanup sites or in drinking water supplies. This article provides a synopsis of the US EPA report, which is available at http://cluin.org/542R06009 . © 2007 Wiley Periodicals, Inc.     

National monument locations and remediation of World War II battle sites

In December 2008, George W. Bush established the World War II Valor in the Pacific National Monument, including eight locations connected with World War II fighting. The executive proclamation designating the monument briefly described the individual sites, mentioning remaining battlefield debris. World War II battle locations in Hawaii and Alaska are currently designated for remediation under different programs of the U.S. Environmental Protection Agency or Department of Defense (DOD). The Pearl Harbor Naval Complex is a “Superfund” National Priority List site. Former military locations in the Aleutian Islands, involved in Japanese occupation and the U.S. offensive to regain control, are included in DOD's Formerly Used Defense Sites (FUDS) remediation program. These monument sites, the regulatory frameworks of the applicable programs, and the current cleanup status are described. © 2009 Wiley Periodicals, Inc.     

Citizen board issues and local newspaper coverage of risk,remediation, and environmental management: Six U.S. nuclear weapons facilities

We examined site‐specific advisory board (SSAB) minutes and local newspaper coverage of the Fernald, Hanford, Idaho, Oak Ridge, Rocky Flats, and Savannah River sites of the U.S. Department of Energy (US DOE) in order to determine the importance of risk‐related issues related to remediation and other forms of environmental management. About one‐third of SSAB issues were risk‐related, and these were disproportionately major issues at meetings. The media focused on risks associated with remediation and other forms of waste management. The analysis implies that contractors and government officials need to establish and maintain communications with advisory panels and accentuate these contacts well in advance of contemplated new actions. © 2008 Wiley Periodicals, Inc.     

Nanotechnology for site remediation

As a remediation tool, nanotechnology holds promise for cleaning up hazardous waste sites cost‐effectively and addressing challenging site conditions, such as the presence of dense nonaqueous phase liquids (DNAPLs). Some nanoparticles, such as nanoscale zero‐valent iron (nZVI) are already in use in full‐scale projects with encouraging success. Ongoing research at the bench and pilot scale is investigating particles such as self‐assembled monolayers on mesoporous supports (SAMMS™), dendrimers, carbon nanotubes, and metalloporphyrinogens to determine how to apply their unique chemical and physical properties for full‐scale remediation. There are many unanswered questions regarding nanotechnology. Further research is needed to understand the fate and transport of free nanoparticles in the environment, whether they are persistent, and whether they have toxicological effects on biological systems. In October 2008, the U.S. Environmental Protection Agency's Office of Superfund Remediation and Technology Innovation (OSRTI) prepared a fact sheet entitled “Nanotechnology for Site Remediation,” and an accompanying list of contaminated sites where nanotechnology has been tested. The fact sheet contains information that may assist site project managers in understanding the potential applications of this group of technologies. This article provides a synopsis of the US EPA fact sheet, available at http://clu‐in.org/542F08009 , and includes background information on nanotechnology; its use in site remediation; issues related to fate, transport, and toxicity; and a discussion of performance and cost data for field tests. The site list is available at http://clu‐in.org/products/nanozvi . © 2008 Wiley Periodicals, Inc.     

Look at groundwater quality to set VOC cleanup levels

In 1981, the Arizona Department of Health Services (ADHS) discovered groundwater contamination by solvents and chromium at the Phoenix Goodyear Airport (PGA), just outside the city of Phoenix. ADHS and the U.S. EPA sampled the site for the next two years, finding that eighteen of their wells were contaminated with trichloroethene (TCE), six exceeding ADHS's action level of five micrograms per liter (μg/l). In 1983, the PGA site was added to the National Priorities List, and, in 1984, EPA began a $3 million remedial investigation, focusing on soils and groundwater. This article discusses how that investigation inspired the authors to develop a stream-lined evaluation method for PGA's volatile organic compounds (VOCs), the process for establishing VOC cleanup levels, and the $26 million of remediation work needed to be done at the site. The heart of this effort is a computer program called VLEACH, loosely standing for VOC-LEACHing, which anticipates the influence of VOCs on PGA's groundwater, even as remediation proceeds.     

Environmental assessment and remediation: Estimating the costs of uncertainty

Current cost estimates for the assessment and remediation of environmental contamination at facilities operated by the U.S. Department of Energy (DOE) are based largely on assumptions, with a resulting high level of uncertainty. Therefore, consistent and reliable methods for estimating the uncertainty inherent in the estimates are of vital importance. This article presents an approach and format for estimating contingency in DOE's Environmental Restoration Program. The method involves an analysis of risk factors having a potential to affect the cost of the major elements in the estimate. Application of the contingency analysis to a project site is included in the discussion.     

Superfund site remediation by landfilling—overview of landfill design,operation, closure,and postclosure issues

This article discusses the appropriateness of using landfills as part of remediating hazardous chemical and Superfund sites, with particular emphasis on providing for true long‐term public health and environmental protection from the wastes and contaminated soils that are placed in the landfills. On‐site landfilling or capping of existing wastes is typically the least expensive approach for gaining some remediation of existing hazardous chemical/Superfund sites. The issues of the deficiencies in US EPA and state landfilling approaches discussed herein are also applicable to the landfilling of municipal and industrial solid “nonhazardous” wastes. These deficiencies were presented in part as “Problems with Landfills for Superfund Site Remediation” at the US EPA National Superfund Technical Assistance Grant Workshop held in Albuquerque, New Mexico, in February 2003. They are based on the author's experience in investigating the properties of landfill liners and the characteristics of today's landfills, relative to their ability to prevent groundwater pollution and to cause other environmental impacts. Discussed are issues related to both solid and hazardous waste landfills and approaches for improving the ability of landfills to contain wastes and monitor for leachate escape from the landfill for as long as the wastes in the landfill will be a threat. © 2004 Wiley Periodicals, Inc.     

Recent developments in cleanup technologies

A recent draft report from the U.S. Environmental Protection Agency's Robert S. Kerr Environmental Research Laboratory in Ada, Oklahoma, entitled ?General Methods for Remedial Operation Perforrmance Evaluation,”? establishes protocols for evaluating and optimizaing the performance of groundwater pump-and-treat systems (EPA 1992). For the first time, EPA proposes guidelines for determining when these systems can be terminated, regardless of whether a site's remediation goals are met. This column reviews the chemical and physical limits of pump-and-treat technology and discusses how these protocols can improve pump-and-treat performance and determine when it may be time to pull the plug.