Approaches for assessing hazards and risks to workers and the public from contaminated land

Many public agencies and private entities are faced with assessing the risks to humans from contamination on their lands. The United States Department of Energy (US DOE) and Department of Defense are responsible for large holdings of contaminated land and face a long‐term and costly challenge to assure sustainable protectiveness. With increasing interest in the conversion of brownfields to productive uses, many former industrial properties must also be assessed to determine compatible future land uses. In the United States, many cleanup plans or actions are based on the Comprehensive Environmental Responsibility, Compensation, and Liability Act, which provides important but incomplete coverage of these issues, although many applications have tried to involve stakeholders at multiple steps. Where there is the potential for exposure to workers, the public, and the environment from either cleanup or leaving residual contamination in place, there is a need for a more comprehensive approach to evaluate and balance the present and future risk(s) from existing contamination, from remediation actions, as well as from postremediation residual contamination. This article focuses on the US DOE, the agency with the largest hazardous waste remediation task in the world. Presented is a framework extending from preliminary assessment, risk assessment and balancing, epidemiology, monitoring, communication, and stakeholder involvement useful for assessing risk to workers and site neighbors. Provided are examples of those who eat fish, meat, or fruit from contaminated habitats. The US DOE's contaminated sites are unique in a number of ways: (1) huge physical footprint size, (2) types of waste (mixed radiation/chemical), and (3) quantities of waste. Proposed future land uses provide goals for remediation, but since some contamination is of a type or magnitude that cannot be cleaned up with existing technology, this in turn constrains future land use options, requiring an iterative approach. The risk approaches must fit a range of future land uses and end‐states from leave‐in‐place to complete cleanup. This will include not only traditional risk methodologies, but also the assessment and surveillance necessary for stewards for long‐term monitoring of risk from historic and future exposure to maintain sustainable protectiveness. Because of the distinctiveness of DOE sites, application of the methodologies developed here to other waste site situations requires site‐specific evaluation © 2007 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 and review: Developing groundwater strategy at the hanford site

The U.S. Department of Energy's (US DOE's) environmental challenges include remediation of the Hanford Site in Washington State. The site's legacy from nuclear weapons “production” activities includes approximately 80 square miles of contaminated groundwater, containing radioactive and other hazardous substances at levels above drinking water standards. In 1998, the U.S. General Accounting Office (US GAO), the auditing arm of Congress, concluded that groundwater remediation at Hanford should be integrated with a comprehensive understanding of the “vadose zone,” the soil region between the ground surface and groundwater. The US DOE's Richland Operations Office adjusted its program in response, and groundwater/vadose‐zone efforts at Hanford have continued to develop since that time. Hanford provides an example of how a federal remediation program can be influenced by reviews from the US GAO and other organizations, including the US DOE itself. © 2008 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.     

Comparison of LLW Disposal Facilities at Major Department of Energy Sites

Near surface disposal facility design and management are examined and compared using a systems approach that defines facility performance as a function of three components (or subsystems): the disposal facility design (cover systems and bottom liners); the properties of the waste (waste composition, waste form and waste package); and the site‐specific environmental features (climate, geology, and hydrology). We report an evaluation of five DOE near surface disposal facility case studies, selected to provide a “representative” sample that included disposal sites with a range of waste and environmental characteristics across the DOE. The facilities selected were the Savannah River E‐Area Engineered Trenches, Hanford Integrated Disposal Facility, Idaho Radioactive Waste Management Complex, Oak Ridge Environmental Management Waste Management Facility, and Nevada National Security Site Area 5. ©2015 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.     

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.     

Choosing remediation and waste management options at hazardous and radioactive waste sites

This article discusses a process for finding insights that will allow federal agencies and environmental professionals to more effectively manage contaminated sites. The process is built around what Etzioni (1968) called mixed‐scanning, that is, perpetually doing both comprehensive and detailed analyses and periodically re‐scanning for new circumstances that change the decision‐making environment. The article offers a checklist of 127 items, which is one part of the multiple‐stage scanning process. The checklist includes questions about technology; public, worker, and ecological health; economic cost and benefits; social impacts; and legal issues. While developed for a DOE high‐level radioactive waste application, the decision‐making framework and specific questions can be used for other large‐scale remediation and management projects. © 2002 Wiley Periodicals, Inc.     

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.     

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.     

Environmental cleanup of the nation's former nuclear weapons sites: Unprecedented public‐private challenges at the largest facilities

In 1994, the U.S. Department of Energy (DOE) initiated a contract reform program intended to strengthen oversight capabilities and encourage the creation of contract and incentive structures, which would effectively facilitate the treatment of onsite contamination and waste. The remedia‐tion and disposal of these legacy wastes is the core of the Department's environmental manage‐ment mission (Government Accountability Office [GAO], 2003). Despite a concerted effort toward achieving the goals of the reform, progress has been slow. Many projects continue to necessitate cost and time extensions above those originally agreed upon. Although the Department insti‐tuted an accelerated cleanup program in 2002, promising to shave some $50 billion and 35 years from its earlier cost and schedule projections, there have been delays in critical project areas that call into question the attainability of the proposed reductions (GAO, 2005). Numerous explana‐tions have been offered as to why achieving these goals has proven so difficult, many of which have concluded that flawed contracting practices are to blame. This article concludes that the root of the problem is much deeper and that the organizational criticisms aimed at DOE are as much a legacy as the waste itself. Although the focus of this article is on large former nuclear weapons sites, these types of contracting and organizational issues are often found at other gov‐ernment and private complex hazardous waste sites. © 2006 Wiley Periodicals, Inc.     

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.     

Stabilization and a multimedia cap for a doe mixed waste site

Closure often of the eleven waste management units covering almost seventy-five acres at the U.S. Department of Energy's Oak Ridge Y-12 Plant has been completed. Costing about $47 million, DOE's accelerated Closure and Post Closure Program (CAPCA) has involved structural waste stabilization and installation of a multimedia cap to contain ferrous metals, salts, uranium, solvents, ethylenediamine tetraacetic acid (EDTA), oils and coolants, asbestos, and material contaminated with radioisotopes. Designs for closure of the remaining waste unit—used for disposing depleted uranium chips, metals, oxides, organic and caustic chemicals, aged ethers, and more—are being prepared now; they will address the potentially explosive and pyrophoric nature of these wastes. This article describes CAPCA's innovative design and construction methods, as well as how its management coordinated the tight schedules mandated by agreements with federal and state regulatory agencies.     

End‐state land uses,sustainably protective systems,and risk management: A challenge for remediation and multigenerational stewardship

This article discusses creating a sustainably protective engineered and human management system in perpetuity for sites with long‐lived radiological and chemical hazards. This is essential at this time because the federal government is evaluating its property as assets and attempting to reduce its holdings, while seeking to assure that health and ecosystems are not put at risk. To assist those who have a stake in the remediation, management, and stewardship of these and analogous privately owned sites, this article discusses current end‐state planning by reviewing the federal government's accelerated efforts to reduce its footprint and how those efforts relate to sustainability. The article also provides a list of questions organized around six elements of risk management and primary, secondary, and tertiary disease and injury prevention. Throughout the article, the U.S. Department of Energy (DOE) is used as an example of an organization that seeks to reduce its footprint, manage its budget, and be a steward of the sites that it is responsible for. However, the approach and questions are appropriate for land controlled by the Department of Defense (DOD), the General Services Administration (GSA), and other public and private owners of sites with residual contamination. © 2005 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.     

Treatment technologies for mercury in soil,waste, and water

Mercury occurs naturally in the environment and can be found in elemental (metallic), inorganic, and organic forms. Modern uses for mercury include chemical manufacturing, thermometers, and lighting (mercury vapor and fluorescent lamps). The chemical and allied products industry group is responsible for the largest quantity of mercury used in the United States. Mercury, particularly the organic methylmercury form, is a potent neurotoxin capable of impairing neurological development in fetuses and young children and of damaging the central nervous system of adults. Mercury regulations span multiple federal and state environmental statutes, as well as multiple agency jurisdictions. In August 2007, the U.S. Environmental Protection Agency's (US EPA's) Office of Superfund Remediation and Technology Innovation (OSRTI) published a report titled “Treatment Technologies for Mercury in Soil, Waste, and Water.“ The report identifies eight treatment technologies and 57 projects, 50 of which provide performance data. This information can help managers at sites with mercury‐contaminated media and generators of mercury‐contaminated waste and wastewater to identify proven and effective mercury treatment technologies; screen technologies based on application‐specific goals, characteristics, and costs; and apply experiences from sites with similar treatment challenges. This article provides a synopsis of the US EPA report, which is available at http://clu‐in.org/542R07003 . © 2007 Wiley Periodicals, Inc. *

1 This article is a U.S. Government work and, as such, is in the public domain of the United States of America.

     

Remediation of the Radioactive Waste Landfill and Chemical Disposal Pits Sites at Sandia National Laboratories

Sandia National Laboratories' Environmental Restoration (ER) Project remediated the Radioactive Waste Landfill and Chemical Disposal Pits (RWL/CDPs) sites located in Albuquerque, New Mexico. The remediation was conducted in 1996 using conventional excavation, as well as hybrid remote robotic manipulation technology at a cost of approximately $3 million. Wastes generated included approximately 73 cubic meters (m³) of debris (including thermal batteries, spark gap tubes, radioactive sources, weapons components, and some classified material), 535 m³ of plutonium-contaminated soil, and 2,294 m³ of soil contaminated with thorium, cesium, uranium, and tritium. The remediation was successful since the project goal of risk reduction was accomplished and no injuries or negative occurrences resulted. This cleanup is one example of the Department of Energy's (DOE's) accelerated approach to environmental restoration. The remediation was performed as a voluntary corrective measure to reduce schedule and budget, compared with the traditional approach following Resource Conservation and Recovery Act (RCRA) regulations.     

Comparison of municipal solid waste management systems in Canada and Ghana: A case study of the cities of London, Ontario, and Kumasi, Ghana

Integrated waste management has been accepted as a sustainable approach to solid waste management in any region. It can be applied in both developed and developing countries. The difference is the approach taken to develop the integrated waste management system. This review looks at the integrated waste management system operating in the city of London, Ontario-Canada and how lessons can be drawn from the system’s development and operation that will help implement a sustainable waste management system in the city of Kumasi, Ghana. The waste management system in London is designed such that all waste generated in the city is handled and disposed of appropriately. The responsibility of each sector handling waste is clearly defined and monitored. All major services are provided and delivered by a combination of public and private sector forces.The sustainability of the waste management in the city of London is attributed to the continuous improvement strategy framework adopted by the city based on the principles of integrated waste management. It is perceived that adopting a strategic framework based on the principles of integrated waste management with a strong political and social will, can transform the current waste management in Kumasi and other cities in developing countries in the bid for finding lasting solutions to the problems that have plagued the waste management system in these cities.     

Public preferences for environmental management practices at DOE's nuclear waste sites

Residents who lived within 50 miles of one of six major US Department of Energy nuclear waste sites were asked in 2005 and again in 2010 to rate environmental management options. Respondents expressed strong preference for continuously sampling the air and water, monitoring worker health, and providing training and equipment to local responders. They strongly supported some site restrictions, such as making sure that the federal government owns the site until no more hazards are present, keeping visitors and recreational users off the site, and requiring government officials to report information to community representatives. The public was much more equivocal about other options, such as restricting new nuclear‐related activities and requiring site managers to live near sites. The authors summarize factors that lead to these public preferences and discuss five population types encountered at these and perhaps other waste management sites. © 2011 Wiley Periodicals, Inc.