Bill Cahill
U.S. Department of Energy
Rick Ferguson
Jacobs Environmental Management (EM)
Team/United Science Industries
Marshall Davenport
Jacobs EM Team/Jacobs Engineering
Group Inc.
ABSTRACT
Alternatives for disposal of wastes generated by remediation of the Oak Ridge Reservation (ORR) are being evaluated under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). One alternative being considered in the feasibility study (FS) is the construction and operation of a waste management facility (the Environmental Management Waste Management Facility, or EMWMF) on ORR. The EMWMF would include a disposal cell, engineered and authorized to accept low-level radioactive waste, Resource Conservation and Recovery Act (RCRA) hazardous waste, Toxic Substance Control Act (TSCA) waste, and mixed waste (consisting of combinations of the previously mentioned categories).
The proposed EMWMF will cover approximately 40-49 hectares (100-120 acres) and consist of an earthen disposal cell with necessary support facilities and additional area for potential future location of treatment, storage, and disposal facilities. The disposal cell is envisioned as a 1.1-million-cubic meter (1.4-million-cubic yard) capacity, above-grade, RCRA-compliant earthen structure with a robust, multicomponent cap.
The U.S. Department of Energy is developing a comprehensive strategy for remediation of ORR. Effort is being made to ensure this evaluation is integrated into this strategy. Should the evaluation determine that on-site disposal is preferred, several issues regarding on-site disposal must be resolved before regulatory approval is received and construction could begin.
This paper presents an overview of the CERCLA evaluation and its incorporation into the remediation strategy for ORR as well as discussion of the key issues associated with on-site disposal. It also briefly describes the conceptual EMWMF design and operations and concludes with several expected benefits of consolidated disposal of waste at ORR.
INTRODUCTION
Development of an on-site waste management facility [the Environmental Waste Management Facility (EMWMF)] in Oak Ridge, Tennessee, is one of three alternatives being considered in a Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) feasibility study (FS) scheduled for submittal to the regulators in the summer of 1997. The FS will address disposal of waste generated during remediation of the Oak Ridge Reservation (ORR) under its Ten Year Plan. This FS, which will also consider no action and off-site disposal alternatives, is necessitated by the limited ability of existing waste management facilities at ORR to indefinitely accommodate large volumes of waste.
Upon conclusion of the evaluation of alternatives in the FS, the preferred alternative will be presented in the proposed plan, which is scheduled to be submitted for public comment in early 1998. A record of decision (ROD) will be prepared that addresses comments received from the public on the proposed plan. The ROD is scheduled to be signed by the U.S. Department of Energy (DOE), U.S. Environmental Protection Agency, and the state of Tennessee in the summer of 1998. Milestones for the submittal of the remedial investigation/FS, proposed plan and ROD to the regulators for review have been established in the Federal Facility Agreement (FFA), which outlines remediation of ORR. Additionally, DOE has set July of 2000 as its goal for the start of operations for the facility (if on-site disposal is the selected alternative in the ROD). Schedule slips have cost ramifications. With aggressive remediation of ORR due to start in 1997, additional storage facilities for the cleanup waste must be constructed if no disposal options are available.
REMEDIATION OF ORR
The remediation strategy for ORR is being developed through two parallel, but integrated initiatives: the ORR Ten Year Plan and the ORR End-Use Working Group. The Ten Year Plan will present planning assumptions regarding remediation scenarios, schedules, required funding, and estimates of the amount and types of waste that will be generated. The End-Use Working Group will define the postremediation ORR. This community-based group will provide recommendations to DOE on the Ten Year Plan, cleanup assumptions and goals, and the return of portions of ORR to the public (footprint reduction). The End-Use Working Group is also expected to assess the need for a centralized disposal facility on ORR. The results of these initiatives, an ORR Ten Year Plan and a definition of the "end state" of ORR, should be available in the fall of 1997. DOE will use these to revise the FFA, schedule and structure future CERCLA evaluations, and subsequently implement remediation.
The ORR Ten Year Plan is recognized as a living document that will be updated as major cleanup decisions for the reservation are documented under the CERCLA process. Five large watershed FSs are currently being written for ORR and will define the remediation strategy for ORR. These watershed evaluations address hundreds of source areas where final cleanup decisions will be made. The RODs for these watershed areas are expected in 1999 and 2000. The Ten Year Plan will then be revised to reflect these decisions.
Like the approach to the remediation reflected in the watershed FSs, DOE has chosen to assess a site-wide approach to the management of the cleanup waste. Under CERCLA, DOE is evaluating the alternatives capable of managing and/or dispositioning waste generated by ORR remediation.
THE CERCLA EVALUATION
The CERCLA evaluation employs a methodology similar to that used to evaluate on-site disposal of cleanup waste at the DOE Hanford site. This approach is consistent with CERCLA, which allows an evaluation of alternatives to remedy a site-wide problem. Like Hanford and in accordance with DOE policy, National Environmental Policy Act (NEPA) values are being incorporated in the CERCLA documentation. DOE will incorporate these values at the environmental impact statement level-of-detail and conduct an expanded community relations program consisting of information sessions and workshops, fact sheets, and development of a crosswalk to identify NEPA values in the CERCLA documentation. The expanded community relations program will also be the link to the development of the ORR end use recommendations.
DOE maintains a comprehensive forecast of waste types and volumes that will be generated during remediation of ORR. Estimates of remediation waste volumes suitable for land disposal were derived from this estimate and include low-level waste (LLW), Resource Conservation and Recovery Act (RCRA) hazardous waste, Toxic Substance Control Act (TSCA) waste, and mixed waste (consisting of combinations of these waste types). Liquid, transuranic, special LLW, and TSCA waste that cannot be treated to meet the RCRA land disposal restrictions (LDR) were not included in this estimate. Also not included were metals, which were assumed to be recycled. This waste is composed of soils, debris (such as construction debris, roofing material, wood, and asbestos/transite), miscellaneous solids (such as treatment residues), personal protective equipment, trash, and sediments/sludges.
Since cleanup assumptions and RODs from the watershed evaluations are not finalized, a waste volume estimate that reflects a high confidence cannot be developed. For this reason, a range of waste volumes has been developed for evaluation in the FS. This waste volume estimate ranges from a minimum volume of approximately 170,000 cubic meters (approximately 223,000 cubic yards) to a maximum volume of approximately 869,000 cubic meters (approximately 1.136 million cubic yards). The current Ten Year Plan is the source of the minimum volume in the range. The maximum volume assumes a more aggressive ORR remediation scenario.
Three alternatives have been developed for the evaluation. The no action alternative, which is required under CERCLA and NEPA, proposes no site-wide alternative for managing waste. It places waste management responsibility at the individual source area. The off-site disposal option proposes appropriately segregating and shipping waste to commercial disposal facilities licensed and/or permitted to accept that waste. This alternative includes actions to implement a large-scale waste shipping campaign such as any required capital improvements to existing waste shipping facilities at ORR or capital expenses such as waste containers and cranes to lift containers from trucks to rail cars.
The on-site disposal alternative proposes the consolidated disposal of most future-generated DOE waste from environmental restoration and decontamination and decommissioning activities. Waste that cannot be treated to meet LDRs or the proposed facility's waste acceptance criteria (WAC) are not considered candidate waste streams for the facility.
The envisioned EMWMF consists of a disposal cell with ancillary facilities to support initial operations and an area for the potential development for future treatment, storage, and disposal facilities. The disposal cell would consist of a 1.1-million-cubic meter (1.4-million-cubic yard) capacity, above-grade, RCRA-compliant earthen structure with a robust, multicomponent cap. Support facilities required for initial operations include those needed for waste staging, temporary storage, and equipment decontamination. An area reserved for future potential expansion would accommodate future facility needs not fully defined at this time. For example, while waste generators will be responsible for treatment to satisfy RCRA LDRs and the facility's WAC, treatment facilities could be located at the EMWMF in the future to enhance overall efficiency of operations. Based on projected waste volumes and cell design assumptions, the disposal cell is estimated to require 24-28 hectares (60-70 acres), with a total EMWMF footprint of 40-49 hectares (100-120 acres), including initial support facilities and an area reserved for future expansion.
The expected economic viability of on-site disposal is one of the key considerations for conducting the evaluation. Preliminary cost comparisons between on-site and off-site disposal indicate a cost savings for on-site disposal of large volumes of waste.
On-site disposal costs were estimated using the life cycle for a disposal facility appropriately sized to accommodate a range of waste volumes from remedial actions. The disposal facility is assumed to be a self-supporting facility with a leachate collection system, equipment decontamination facilities, a waste staging area, truck scales, etc., with the exception of leachate treatment, utilities, and fire and safety services, which are assumed to be provided by existing DOE facilities. The life cycle of the facility includes design, construction, operations, and post-closure maintenance and monitoring. Operations costs were estimated using the operations contract for the Hanford Environment Restoration Disposal Facility. A unit cost was derived by plotting the life cycle cost of the facility against the range of volumes being considered for disposal.
Off-site disposal costs were estimated by considering volumes of waste which could meet the WACs for appropriate commercial disposal facilities. LLW and mixed waste (soil and debris) would be shipped to Envirocare of Utah, and RCRA hazardous and TSCA waste would be shipped to the Chemical Waste Management Emelle, Alabama, disposal facility. Unit costs for disposal (as reflected in existing contracts accessible to DOE) were combined with an estimate for packaging and transportation costs (also based on vendor quotes, contracts, and actual costs) to arrive at a unit cost.
This economic viability analysis will be updated using revised waste types and volumes and more detailed cost information to support the FS evaluations.
ON-SITE DISPOSAL ISSUES
Should the evaluation determine that on-site disposal is preferred, several issues regarding on-site disposal must be resolved before regulatory approval is received and construction could begin. The first issue pertains to permitting the facility under RCRA and TSCA.
These permits could be required if ORR is not considered by the regulators as a single "site" under CERCLA. Under this definition, RCRA and TSCA permits would be required to dispose of remediation waste from "off-site" sources. For example, if the disposal facility is located at the Oak Ridge National Laboratory, wastes from the K-25 Site and Y-12 Plant would be interpreted as "off-site" waste, and the facility would have to be permitted to accept waste from these "off-site" sources.
Because permitting would be have to be performed in parallel with the evaluation to maintain schedule, a potential for permitting requirements to contradict the intent of the CERCLA process exists. For example, an application for a Part B RCRA permit for a disposal facility usually includes a near-complete (90-100 percent) design package and plans for operations, closure, and post-closure monitoring. Performing this work before a ROD is approved is discouraged under CERCLA because such an effort could prejudice the outcome of the alternatives evaluation. This issue could be avoided by sequencing these activities. However, this would delay the scheduled opening of the disposal facility.
DOE is working with the state of Tennessee and EPA to define the EMWMF as on-site for all CERCLA response actions that will take place on ORR. It is DOE's position that the EMWMF and all areas of contamination on ORR are cumulatively one CERCLA site. To date, reactions from the regulators have been positive. If successful, permitting will be removed from the critical path, possible contradictions will be avoided, and money will be saved.
Two DOE programmatic issues have been identified. The first concerns the dual sources of requirements for the management of DOE LLW--CERCLA and DOE Order 5820.2A. DOE-Oak Ridge Operations (ORO) will address the duplication of requirements and integrate them into a single set of requirements for this evaluation.
CERCLA requires that remedial alternatives being evaluated include an estimate of the long-term risk associated with their implementation. Risk estimates for the implementation must fall with a target risk range of 1 x 10-4 to 1 x 10-6. DOE Order 5820.2A requires a performance assessment for DOE's waste management facilities. Future doses to the public are estimated in this assessment and cannot exceed performance objectives prescribed in the Order. Direction and guidance for the development of risk assessments and performance assessments accompany the two requirements.
DOE-ORO has developed a strategy for satisfying the requirements of DOE Order 5820.2A. The requirements will be incorporated into the evaluation using a DOE policy statement issued May 31, 1996, which states that "the CERCLA process shall be used to demonstrate compliance with the requirements and intent of DOE Order 5820.2A with regard to the safe management and disposal of onsite environmental restoration LLW." The policy includes an example crosswalk developed at the Fernald Environmental Management Project, which addresses integrating both CERCLA and DOE Order 5820.2A requirements.
While the intent of both requirements is protection of human health, methodologies outlined and assumptions contained in the requirements and guidance differ. Three points of divergence exist between the requirements: the period of time being assessed, the period of time credit can be taken for institutional control and the related requirement in the DOE Order for an assessment of exposure to an "intruder" who gains permanent access to the facility once institutional control is assumed to be discontinued.
DOE Order 5820.2A is being revised by DOE-Headquarters in response to comments from the Defense Nuclear Facilities Safety Board. DOE-ORO is participating with DOE-Headquarters working groups to revise the Order. The revised Order will defer to 10 CFR 834, which will technically substantiate 1,000 years or less period of assessment; institutional control beyond 100 years; and a credible intruder assessment scenario(s).
DOE-ORO intends to cite the CERCLA requirements for 5-year reviews and land use decisions developed by the End-Use Planning Group as rationale for departure from the DOE Order. The revision to the Order will most likely result in the interpretation and implementation of institutional controls in a manner similar to that being considered by DOE-ORO for this evaluation.
Funding is the second programmatic issue. In an era of budgetary restrictions and budget cuts, approximately $85 million is required during the next 4 years to bring the EMWMF online. To fund this facility at the expense of the remediation of ORR would be counterproductive. DOE-ORR has developed a funding approach that can make the EMWMF a reality on schedule without impacting the remediation it is intended to support.
DOE is pursuing privatization of the facility. Under this scenario, DOE develops design and performance specifications for the EMWMF and commits to obtaining the necessary permits. Following contract award, a private-sector vendor designs, constructs, and operates the facility. Capital cost for the facility is recouped through the operator's unit cost disposal fee negotiated in the contract. The design and performance specifications will minimize design, construction, and operational unknowns and avoid unnecessary constraints. This will result in less risk to the vendor, which should be reflected in a lower unit cost proposal during the procurement.
POTENTIAL BENEFITS OF THE EMWMF
DOE expects the EMWMF to offer several benefits to stakeholders. On-site disposal capacity will streamline ongoing evaluations and expedite cleanup activities. Large volumes of waste from the cleanup of ORR are expected to make off-site transportation and disposal costs significantly higher than on-site disposal costs. This savings would result in additional funding available for remediation of ORR. Removal of additional waste sources would reduce the total risk of the reservation. Finally, consolidating waste management and disposal activities as opposed to capping multiple, discrete waste units in place with continued maintenance and institutional controls would reduce the future mortgage for ORR and allow for greater reduction in the ORR footprint.
CONCLUSION
The CERCLA evaluation of alternatives capable of managing and/or dispositioning waste generated by ORR remediation is scheduled to conclude with a ROD in mid-1998. Resolution strategies for all issues are developed and are being implemented. If the results of the evaluation confirm assumptions, DOE could construct a disposal facility on ORR.
An on-site disposal facility could result in more land being returned to the public for beneficial use and less risk associated with portions of the reservation that remain under federal control.
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