EPA WATCH Dioxin sources, levels to be revised A more thorough characterization and better data on dioxin deposition, emission sources, and levels in food are expected in the final EPA dioxin risk assessment document. The changes will reflect information EPA has received in public comments or is collecting, according to John Schaum, chief of the Exposure Assessment Methods Branch. The new data likely will result in modified industry dioxin emissions figures in the final risk assessment, scheduled to be released late this year, Schaum said. The result, he predicted, will lower EPA's dioxin emissions figures for medical waste incinerators. Medical incinerators were considered the top dioxin source in the draft dioxin assessment, released in September 1994. The medical waste revisions, Schaum said, resulted primarily from American Hospital Association comments demonstrating that the amount of waste hospitals incinerate is lower than EPA's estimates. He would not say whether medical incinerators would still be considered a major source. Additional emissions data are being collected for coal power plants, mobile diesel engines, and the ferrous and nonferrous metals industry, Schaum said, and will be contained in the final risk assessment. Many of these emitters had been suspected sources, and although their emissions had been measured in other countries, they had not been characterized in the United States, Schaum said. The Agency is using computer models that couple emissions rates of known dioxin generators with large-scale atmospheric models to determine and predict U.S. dioxin deposition, Schaum said. EPA is planning to expand its system of dioxin monitors at several locations across the country. This effort will attempt to measure vapor deposition into plant life as well as wet and 348
dry deposition. Vapors holding dioxin are considered to be the dominant pathway to plants, which are the entryway to the human food chain. With the Department of Agriculture, EPA also plans to begin a program to measure dioxin in pork, milk, and poultry, Schaum said.
Superfund reforms announced Through a series of internal Superfund-related reforms, EPA hopes to spur faster cleanup and redevelopment of contaminated and abandoned industrial sites. The changes were released as a guidance in the July 3 Federal Register. The reforms include: • Two new enforcement policies intended to cut liability for prospective purchasers of contaminated properties in return for site development; • An internal directive to ensure that EPA considers potential future use of Superfund sites when planning site-specific cleanups; • Administrative modifications that allow deferment of national listing for Superfund sites if states or tribes step in to oversee cleanups; and • Modifications to encourage a wider range of choices to allocate costs among potentially responsible parties and greater use of alternative dispute resolution techniques when allocating costs. According to EPA, its intention is to speed cleanup of abandoned contaminated urban sites or brownfields, in part by helping to assure potential developers that they will not be held liable for past contamination. For instance, under one guideline, the EPA Office of Enforcement and Compliance Assurance would allow developers who took on a contaminated property to avoid liability as long as their actions did not result in further contamination. Through another of the reforms, site owners and communities would be offered a way to avoid the stigma
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and legal obligations of a Superfund site listing if the state oversees the cleanup and finds someone to pay for it.
New hazardous waste baselines proposed Forced by a 1991 court decision to revise its rules on handling and disposal of treated hazardous wastes, EPA is working to develop new baseline concentrations for nearly 400 hazardous constituents listed under the Resource Conservation and Recovery Act (RCRA). These baseline levels will be used to define when a listed waste must be handled under rigorous hazardous waste provisions of RCRA Subtitle C. EPA is under a more recent court order to release the proposal, called the Hazardous Waste Identification Rule, in August. The 1991 court decision overturned the "mixture and derived from" rule that was written to close a loophole that allowed waste generators to dilute hazardous chemicals into a mixture and thereby remove them from Subtitle C, according to Gregory Helms of the Office of Solid Waste. Until it was overturned, the mixture and derived-from rule called for these wastes to be handled as hazardous waste, despite dilution. Waste treaters such as Doug MacMillan, executive director of the Environmental Technology Council, worry that the proposed revision may give too much leeway to waste generators. The council brought suit to force the August release of the proposal. MacMillan said EPA's proposal relies too much on a "self-implementing system for generators" that would allow the substitution of "generator knowledge" for sampling to determine the constituents in a waste stream. MacMillan also warned of "unpredictable outcomes" for the rule because regulatory authority for delisted wastes will fall to the states. He said several states lack standards for industrial nonhazardous waste disposal.
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EPA has requested that the Science Advisory Board (SAB) address a series of questions concerning the rule's provisions for assessing risks. According to Stephanie Sanzone, SAB staff member, the board is being asked to examine the baseline concentration that would be extrapolated from the de minimis level as an endpoint through fate-and-transport models. Assuming a 10~R cancer risk for an endpoint for carcinogenic constituents, the assessment methodology works backward to determine the concentration of a substance that through transport, degradation, and fate would fall below that risk level, Sanzone said. Levels would be adjusted for noncarcinogenic substances, according to Helms. The methodology does not consider multiple pathways, nor does it account for multiple constituents, according to Sanzone. The final rule is expected to be released in December 1996.
Site classification system pilot planned A citywide environmental classification system intended to speed the cleanup of contaminated urban property is being developed in Oakland, CA, by EPA Region IX and state and local agencies. The program may serve as a model for other inner city settings, according to Martin Rodriguez, EPA Region IX work assignment manager for the project. By late September EPA hopes to have a trial classification system in place that will break the city into environmental zones and provide risk-based "look-up tables" to determine the level of cleanup required based on the contamination at a particular site and the area's physical environment. The site classification plan will be based on the physical sensitivity of the location, Rodriguez said, for instance, its hydrology and geology. Ten sites throughout the city are being examined in detail to develop the classification plan by city zone. The zone data will be used by property owners and potential developers to estimate the cost of cleanup, based on the protection needed for a site's environmental classification, and the risk-based cleanup level, based on contamination present at the site and its intended use. Although a site-specific
assessment will be necessary for an actual cleanup, a "predetermined screening level" study for a class of sites should encourage development by eliminating initial uncertainties, according to EPA. The demonstration project grew out of a meeting two years ago between the EPA administrator and Oakland city officials. EPA has committed $135,000 to prepare the classification scheme, Rodriguez said. The program's goal is to clean up and reuse some 600 leaking underground storage tank sites that dot Oakland, according to EPA. Oakland officials hope the program will encourage property owners and developers to pay for cleanups by providing certainty and removing the many levels of bureaucracy that usually accompany approval of an environmental cleanup, even for non-Superfund projects such as these. Rodriguez noted that it has been very difficult to find developers willing to clean up and use these sites, which are mostly closed gasoline stations and auto repair shops. These uniform procedures must be approved by many agencies, including EPA and several state and local bodies. Oakland is also seeking approval of the program by community groups. Rodriguez estimates that actual site-specific investigations, geared to a use, will begin late this year or early in 1996.
Regulatory cost-benefit analysis to expand Better quantification of benefits from proposed environmental regulations is among changes expected in an internal EPA guidance that is nearing completion by the Office of Policy, Planning, and Evaluation. The guidance will help inform EPA decision makers of net cost and benefits for a proposed regulation. A draft is expected to be released to the EPA Science Advisory Board late this summer. The document is in compliance with Executive Order 12866, issued September 1993, which called for an overhaul of the federal rule-making process. It updates a Reagan-era directive that requested regulatory impact analyses for rules worth more than $100 million. The directive took a traditional economic approach to determining costs. The new guidance, however, will broaden that approach to include other features of
economic analyses, such as valuing benefits and presenting uncertainties in economic calculations. For instance, the guidance will address the cost of illnesses, inequities in the distribution of a rule's impact, a regulation's ecological effect, its impact on future generations, and environmental justice concerns, according to Brett Snyder, chief of the economics analysis and research branch in the policy office. Also considered in the guidance will be a rule's costs and benefits to states and local governments. Snyder emphasized that traditional cost calculations are also discussed in the rule, but in this area there are already substantial data and a history of methodology. On the other hand, emphasis on the murky area of valuing benefits has increased in recent years, and the Executive Order specifically calls for greater consideration of the value of less tangible costs and benefits when developing regulations. The guidance's influence, however, may be limited by congressional action, Snyder said, noting that the House has passed legislation calling for risk-benefit calculations and several bills are pending in the Senate.
ORD drafting strategic research plans The Office of Research and Development (ORD) has begun drafting a long-term strategic research plan that includes a mission statement for the office, research criteria, a series of research goals, and an inventory and assessment of science within ORD laboratories. Speaking to the Science Advisory Board's Research Strategies Advisory Committee in June, ORD head Robert Huggett said that his office would also contract with the National Academy of Sciences to detail a decade-long research strategy. According to Joseph Alexander, ORD's assistant administrator for science, the first draft of the strategic plan should be complete by October and finalized by February 1996. On that schedule the plan will not be incorporated into ORD's budget until fiscal year 1998. Huggett said ORD had received approval under the Federal Advisory Committee Act (FACA) to conduct outside peer review of grants and fellowship applications.
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