The Need for Uniform Soil Cleanup Goals
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critical and often time-consuming component in developing and implementing remediation plans for contaminated land sites in the United States has been the development of remediation goals for groundwater and contaminated soil, particularly the latter. Since the passage of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (Superfund), such goals have been established on a site-by-site basis. The original act contained little guidance on groundwater and soil remediation goals, which resulted in the use of a wide range of methods-mostly negotiation with responsible parties at each site-in early site remediation efforts. The situation is much the same for corrective measures and closures under the Resource Conservation and Recovery Act (RCRA) and many site remediation programs at the state level. In the Superfund Amendments and Reauthorization Act (SARA) of 1986, Congress attempted to bring order to the establishment of remediation goals at Superfund sites by setting up a process for their development. This process involves evaluation of Applicable or Relevant and Appropriate Requirements (ARARs) set by other environmental laws and regulations (e.g., use of Safe Drinking Water Act maximum contaminant levels for groundwater) and, where no ARARs can be identified, performance of a site-specific, humanhealth-focused risk assessment to identify appropriate cleanup levels. Although this process has narrowed the range of methods used to establish groundwater and soil remediation goals, it nevertheless contains a great deal of flexibility to allow for site-specific conditions and thus the optimum use of resources. Although the reasons for a flexible remediationgoal-setting process are laudable, namely, to achieve consistent human-health risk levels at 0013-936)(/93/0927-765$04.00/0 0 1993 American Chemical Society
various sites and to make the best use of resources, this flexibility has slowed remediation decision making and resulted in the establishment of inconsistent remediation goals for similar sites around the country. Inconsistent goals for soil remediation have been particularly troublesome as few ARARs can be identified for this medium. Concerned environmental organizations, industries, and citizens have called for the establishment of uniform soil cleanup goals, perhaps with some consideration of land use. This appeal is also being voiced by “front line” state and federal regulatory personnel who want to be able to defend recommended solutions convincingly and be consistent and equitable, and who usually do not have the time or resources to perform, evaluate, or defend thousands of site-specific risk assessments. Some states, most prominently New Jersey, are responding to the clamor from these parties by proposing specific, concentration-based soil cleanup criteria for a variety of metals and organic compounds found commonly at contaminated sites. These states have followed the lead of several European countries and Canada, where nationally consistent, concentration-based uniform soil guidelines have been or are being established. We believe that there is growing national consensus on the need for uniform soil remediation goals for common contaminants, at least as default values to be used in the absence of a site-specific risk assessment. This consensus was quite evident at the January 1993 Water Environment Federation Specialty Conference, “The Development of Soil, Sediment, and Groundwater Cleanup Standards for Contaminated Sites: How Clean Is Clean?,” in which members from all of the constituencies discussed above participated. Certainly, none of the groups advocates abandoning site-specific flexibility altogether. Rather, there is increasing agreement that a hybrid apEnviron. Sci. Technol., Vol. 27, No. 5,1993 765
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proach may be most desirable. Uniform soil cleanup goals could be developed for use as default values, but at sites where potentially responsible parties or state and federal regulators feel that a predetermined uniform value is inappropriate, an alternative level could be developed by means of a site-specific risk assessment. This would leave the decision to fund a costly sitespecific assessment largely up to the parties responsible for cleanup. They could assess for themselves the trade-off between remediation to a potentially too-stringent level if the default value were used, and the cost of an assessment to determine a more appropriate goal that might result in reduced remediation costs. At the same time, it would reduce the burden on the regulatory agencies because it would decrease the need for detailed site-specific assessments. To avoid having 50 different sets of soil remediation goals, among other reasons, federal leadership is needed and is evolving. EPA and the Department of Energy are working together to investigate the risk assessment and management issues that need to be addressed in the development of a set of uniform goals. We view the growing consensus on the need for such goals as a positive step toward acceleration of site cleanups and more consistency in remediation achievements.
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David A. Dzombok. an assistant professor in the Department of Civil Engineering at Carnegie Mellon University, teaches and conducts research in water and soil quality engineering. He holds a Ph.D. in civil-envhnmentol engineering from the Massachusetts Institute of Technology.
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766 Environ. Sci. Technol.. VoI. 27, No. 5. 1993
Paula A. Labieniec is a doctoral candidate in the departments of Civil Engineering and Engineering and Public Policy at Carnegie Mellon University. She has o fellowship from the US.Department of Energy's Environmental Restoration and Waste Management Pragram.
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Robert L. Siegrist is a research stoff member with the Environmental Sciences Division at Oak Ridge National Loboratory, He has a Ph.D. in environmental engineering from the University of Wiscons i n . His research interests i n c l u d e characterization and remediation of hazardous waste-contaminated sites.
