[Federal Register Volume 60, Number 186 (Tuesday, September 26, 1995)] [Proposed Rules] [Pages 49537-49539] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 95-23840] ----------------------------------------------------------------------- [[Page 49538]] ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 264, 265, 270, and 271 [FRL-5303-3] Corrective Action for Solid Waste Management Units (SWMUs) at Hazardous Waste Management Facilities AGENCY: Environmental Protection Agency. ACTION: Notice of Response to Comments. ----------------------------------------------------------------------- SUMMARY: On June 2, 1994, the Environmental Protection Agency (EPA) published a Notice of Data Availability (NODA) and request for comment in the Federal Register, which announced the availability of a revised draft Regulatory Impact Analysis (RIA) prepared by the Agency for the proposed Resource Conservation and Recovery Act (RCRA) requirements for corrective action for solid waste management units at hazardous waste management facilities. The information included data in support of the proposed Subpart S rule relating to corrective action, published on July 27, 1990, and the final rule for Corrective Action Management Units (CAMUs) and Temporary Units (TUs), promulgated on February 16, 1993. This notice constitutes a response to comments received on that NODA. ADDRESSES: Copies of the comments may be obtained by calling or visiting the RCRA Information Center. The RCRA Information Center is located in Room M2616 at EPA Headquarters and is available for viewing from 9 a.m. to 4 p.m., Monday through Friday, excluding Federal holidays. Requests for obtaining the document by telephone may be made by calling (202) 260-9327. Copies cost $0.15 per page. FOR FURTHER INFORMATION CONTACT: For general information, contact the RCRA/Superfund Hotline, Office of Solid Waste, U.S. Environmental Protection Agency, 401 M Street, SW, Washington, DC 20460, telephone (800) 424-9346; in the Washington, DC metropolitan area the number is (703) 412-9810, TDD (703) 412-3323. SUPPLEMENTARY INFORMATION: I. July 27, 1990 Proposal On July 27, 1990 EPA proposed a comprehensive rule (Subpart S, 55 FR 30798) specifying corrective action requirements for facilities regulated under Subtitle C of the Resource Conservation and Recovery Act (RCRA) as amended by the Hazardous and Solid Waste Amendments (HWSA) of 1984. The proposed rule was developed to provide both the technical (e.g., action levels, investigation aspects, remedy selection criteria, etc.) and procedural aspects (e.g., definitions, reporting and permitting requirements, etc.) of corrective action. A Regulatory Impact Analysis (RIA) to estimate the costs and benefits of the Subpart S proposed rule was developed to support the proposed rule. In that proposal, the EPA explained that it would continue to refine its estimates and make the results available to the public. In the June 2, 1994 Federal Register Notice of Data Availability and request for comments, EPA made available the revised draft Subpart S RIA that includes supporting data regarding studies conducted by EPA concerning the use of CAMUs in RCRA corrective actions. EPA used these supporting data in a rulemaking authorizing the establishment of CAMUs (58 FR 8658, February 16, 1993). Although the CAMU rulemaking included a supplemental notice (57 FR 48195, October 22, 1992) as well as a separate RIA and a summary report, some commenters requested additional information on the data supporting that analysis. EPA believes the summary report provided sufficient detail for purposes of the CAMU rulemaking. However, because the results of the CAMU RIA will be relevant to the regulatory options analysis in the final Subpart S RIA, as well as a related RCRA rulemaking initiative known as the Hazardous Waste Identification Rule (HWIR) for contaminated media, a more detailed breakdown of the CAMU data was included in the supporting data made available through the June 2, 1994 Federal Register notice. EPA believes the data made available through the June 2, 1994 Federal Register notice satisfy the outstanding requests for additional information on the data supporting the CAMU rulemaking. To date, EPA has received ten (10) sets of public comments on these data. EPA has evaluated these comments and believes that none of the issues raised by the commenters indicate a need for EPA to re-visit the impact analysis done in support of the CAMU rulemaking. However, because of the potential relevance of these comments to EPA's ongoing rulemaking efforts, EPA will continue to evaluate and respond to comments within the context of the Subpart S RIA and HWIR rulemaking for contaminated media. II. Summary of Public Comments As of the July 18, 1994 deadline, ten (10) commenters had submitted letters with comments regarding the data made available through the June 2, 1994 Federal Register notice. A number of commenters stated that the Subpart S proposal is likely to be affected by the HWIR rulemaking for contaminated media, and recommended that the impact of the HWIR rulemaking be reflected in the Subpart S rulemaking. In addition, commenters raised a number of issues regarding the methodology and assumptions used for the draft RIA. EPA agrees that events that have occurred since the Subpart S proposal was issued, including the development of HWIR, should be taken into account in the Subpart S rulemaking. Because EPA is now considering how to proceed with the Subpart S rulemaking, the Agency is not providing a detailed response to these comments at this time. However, EPA will take these comments into account when deciding whether to finalize or repropose portions of the Subpart S proposal. One commenter, in addition to addressing the RIA methodology as it applies to the Subpart S proposal, also addressed its applicability to the final CAMU rule. The commenter first argued that EPA's failure to conduct sensitivity analyses on the effects of parameter uncertainty undermined many of the draft RIA's conclusions. In response to this comment, EPA conducted an analysis in the Draft RIA for the Final Rulemaking on Corrective Action for Solid Waste Management Units in which OSW identified and evaluated the sources, magnitude, and consequences of uncertainty in predictions of chemical concentrations and exposures in the multimedia fate and transport modelling component of the RIA. The scope of the analysis of uncertainty focused on predictions of concentrations and exposures from unremediated sites using a Monte Carlo version of MMSOILS (a multimedia contaminant fate, transport, and exposure model) at two sample facilities (one facility and environmental setting was well characterized, the other was limited.) The two sample facilities were subjected to quantitative (sensitivity) analyses of the effects of parameter uncertainty on chemical concentration, with the Monte Carlo results used to estimate the cumulative distribution frequency of the chemical concentration in ground water, surface water, air, agricultural and food products, and biota. In addition, Monte Carlo parameter sensitivity methods were used to evaluate model sensitivity to parameter uncertainty. Further, the commenter argued that, because no sensitivity analyses were performed on sample selection, facility characterization, contaminant releases, remedy selection, remedy effectiveness, human health and ecological benefits, averted water use costs, residential [[Page 49539]] property value changes, and cost/ benefit comparisons, results may not be reliable in predicting decision-making during actual corrective actions. EPA does not believe that this type of analysis was necessary here, since the RIA did take account of potential uncertainty. In the draft RIA, EPA conducted a stratified random sampling procedure developed to maximize the precision of the population estimator in extrapolating the sample findings to the corrective action population. In addition, EPA used information collected from EPA Regional files and state regulatory agency files with regard to facility operations and history, environmental setting, SWMU characteristics, extent of existing contamination, and potential receptors to substantially increase the reliability of the draft RIAs conclusions. All of these factors reduce the need for additional uncertainty analysis. Therefore, EPA believes that the scope of the uncertainty analysis was adequate and further sensitivity analyses were not required. However, EPA will continue to assess this issue as the Agency moves forward with the Subpart S rulemaking. The commenter also argued that the draft RIA's conclusions, which are based on the proposed Subpart S rule, do not apply to corrective actions performed under the final CAMU rule, which differs from the proposal. Another commenter also suggested that the draft RIA should be revised to reflect the promulgation of the CAMU rule. The commenters are correct that the draft RIA incorporates the proposed CAMU rather than the final version. However, as indicated above, EPA in its June 2, 1994 Federal Register notice made available a more detailed breakdown of data supporting the final CAMU RIA so that commenters would have additional information on the data supporting the final version of the CAMU rule. EPA believes that this supplemental material, along with the information provided in the CAMU RIA, provides sufficient support for the final rule. The final CAMU rule expanded the CAMU concept from the July 27, 1990 proposed rule to increase flexibility in selection of more cost-effective remedies, increase treatment of waste and contaminated media, and speed implementation of the program. According to the supplemental data and analyses, remedy selections based upon the more flexible expanded CAMU provisions, using facility-specific data on actual contamination (where available) and modelling data to estimate the extent of contamination, allow for consolidation of contaminated media prior to treatment and result in more treatment of waste that otherwise would not be treated. The commenter also stated that the remedy selection process was flawed because the technical panels did not fairly represent real-world facilities and time frames. EPA disagrees; the process contained a number of safeguards to assure that it was representative of actual decision-making. In order to account for the complexity of the decision-making process when simulating the selection of remedies, EPA developed an approach that relied on panels of experts to select remedies at the sample facilities. In order to capture the interactions between EPA and the facility, EPA convened policy and technical expert panels. Policy panels were identified and selected by officials in EPA's Office of Solid Waste to represent the role of the regulatory agency in setting remedial objectives, assess technical information on the performance of potential remedies, and make final remedy selection decisions. The policy panels consisted of experienced Regional EPA and State regulatory staff with expertise in a variety of technical areas including geology, engineering, and risk assessment. Technical panels consisting of national remediation experts were identified through a selective search across many well-recognized firms in the U.S., representing the hydrogeology, geology, geochemistry, soil science, civil, chemical, or environmental engineering, and chemistry disciplines. The technical panels developed the technical remedies for each facility based on guidance from the policy panel, then estimated the costs of the remedies. Because sample facility scenarios were based upon actual facilities, actual owner/operators were not employed in determining remedy selections at the sample facilities in order to ensure the confidentiality of sample facility deliberations and remedy selections determined by the expert panels. However, the qualifications of the selected experts made them well-suited to take on the decision- making role of owner/ operators. Time constraints imposed upon the expert panels reflected the simplified decision making process specified in the ground rules for the expert panel process as described on page 4-4 of the RIA. The CAMU provisions specified five decision factors for selecting remedies: long-term reliability and effectiveness; reduction of toxicity, mobility, or volume of wastes; short-term effectiveness; implementability; and, cost. Agency officials were present throughout the expert panel process to resolve specific questions concerning the interpretation/applicability of current Agency policy and to ensure that remedial objectives were consistent with the CAMU provisions. Accordingly, the expert panel process, though somewhat simplified compared to the actual decision-making process, involved a consideration of relevant factors by qualified experts. As such, it adequately represented real-world decisions for purposes of this rulemaking. Based upon results of the impact analysis done in support of the CAMU rulemaking, as well as the above discussion in response to public comments, EPA believes it is not necessary to re-visit the regulatory impact analysis for the CAMU rulemaking. Dated: August 24, 1995. Elliott P. Laws, Assistant Administrator, Office of Solid Waste and Emergency Response. [FR Doc. 95-23840 Filed 9-25-95; 8:45 am] BILLING CODE 6560-50-P