The U.S. Nuclear Regulatory Commission (NRC) is considering issuing an amendment to Source Materials License No. SMB-1408, held by Molycorp, Inc. (Molycorp or licensee), to authorize decommissioning of its facility in York, Pennsylvania. The objective of the decommissioning is to remediate the areas contaminated with thorium, uranium, and their daughter products, to allow the NRC to release Molycorp's York property for unrestricted use and to terminate the NRC radioactive materials license.
Environmental Assessment Summary
In connection with the decontamination and decommissioning of its York facility, the licensee proposed the following activities: Decontamination and removal of buildings and other above-grade structures, with the exception of an office building and a warehouse, removal of concrete slabs and associated drains and sumps, excavation of the contaminated material exceeding the Site Decommissioning Management Plan (SDMP) Action Plan unrestricted use criteria (46 FR 52061), restoration of excavated areas with clean overburden, and transportation of the radioactively contaminated materials to an NRC approved interim storage or disposal facility. Further details are provided in the Environmental Assessment (EA).
Based on the NRC staff evaluation of the Molycorp's final Decommissioning Plan (DP), it was determined that the proposed decommissioning can be accomplished in compliance with the NRC public and occupational dose limits, effluent release limits, and residual radioactive material limits. In addition, the approval of the proposed action (i.e., decommissioning of Molycorp's, York, Pennsylvania, facility in accordance with the commitments in the NRC license SMB-1408 and the final DP) will not result in a significant adverse impact on the environment.
Need for Proposed Action
The proposed action is necessary to remove the radioactive material attributable to licensed operations at the site to levels that permit unrestricted use of the site and termination of the radioactive source materials license SMB-1408.
Environmental Impacts of the Proposed Action
NRC staff reviewed the levels of contamination, the proposed remediation and decommissioning methods, and the radiological release criteria that will be used during the remediation and decommissioning. The radiological criteria are specified so that decommissioning activities will meet the 10 CFR part 20 radiation protection requirements. Worker and public doses will be limited so that exposures will not exceed Part 20 requirements and are as low as is reasonably achievable (ALARA).
The licensee will perform remediation in accordance with NRC's Action Plan to ensure timely cleanup of SDMP sites (57 FR 13385) and transportation of the excavated materials to an NRC approved interim storage or disposal facility.
The information for the York DP includes additional analyses of worker exposures from normal operations and an assessment of the potential for accidents. Because of the limited nature of activities planned for the York facility, potential worker exposures will most likely result from inhalation of airborne dust and shine from direct radiation. Potential public exposures are limited to inhalation of contaminated airborne dusts.
Information provided by the licensee indicates that past activities resulted in no measurable internal or external dose to any workers. The past activities included radiological characterization and building decontamination similar to the proposed activities. Therefore, radiation doses to workers from these activities are expected to be well within the limits of Part 20. Separate dose calculations to assess the impacts indicated that the excavator at the York site will receive an estimated maximum annual dose of 10.6 millirem (mrem) (predominantly from external exposure). The Part 20 annual worker dose limit is 5 rem (5000 mrem). As the estimated dose is well below the limit, no adverse impacts are expected based on the exposure calculations.
NRC staff analyzed the radiological impacts to the public from the planned decommissioning activities. Potential radiological impacts to the public from the decommissioning operations at the York facility are limited to similar release mechanisms pertaining to worker exposures (decontamination and excavation dusts), but require transport over greater distances to reach potential receptors. Therefore, much lower concentrations and doses are expected for members of the public in comparison to workers. The licensee estimated the public exposure at the York site boundary due to excavation to be about 0.059 mrem/yr. This dose is well below the NRC public dose limit (Part 20) of 100 mrem/yr, providing confidence that the potential for adverse environmental impacts is low. The licensee has included in its DP, further groundwater sampling and characterization to reduce uncertainty in current estimates and to assure that mitigative measures are not warranted. Therefore, NRC staff concludes that the licensee has provided adequate plans to ensure that potential radiological impacts to members of the public from the proposed decommissioning activities will not exceed NRC limits and are unlikely to result in adverse environmental impacts.
NRC staff also assessed the radiological impacts from transportation of contaminated soil and other wastes from the York site to an NRC approved interim storage or disposal facility. The most significant exposure pathway for the truck driver was estimated to be from direct exposure. The total radiation dose to the truck driver was estimated to be from direct exposure. The total radiation dose to the truck driver was estimated at 5.42 mrem for all shipments and 3.33 mrem during transport only (for comparison, the Part 20 occupational dose limit is 5000 mrem/yr). Other scenarios, such as transporting the wastes to another storage facility (example: Envirocare waste facility in Clive, Utah), were also considered and the resulting dose to the worker was found to be well below the NRC occupational dose limit. Also, the public dose from transport would be far less than that for the driver. NRC staff reviewed the calculations and found the doses and intakes are well within Part 20 limits.
NRC staff evaluated the radiological impacts from potential accidents. The information in the York facility DP states that potential site accident scenarios are unlikely to lead to doses that exceed 1 percent of the Part 20 dose limits. Potential accident scenarios considered include fire and loading or transfer mishaps. Considering the low potential for fire or explosion in existing building structures, the low quantities of material used during transfer operations, and the lack of highly concentrated radioactive materials at the site, NRC staff concludes that accidental releases of radioactive materials in quantities that could affect public health and safety are unlikely. The licensee has a procedure in place for emergency Start Printed Page 30141response and notifications that provides additional safety assurance and, therefore, NRC staff concludes that the licensee has adequately addressed the potential for radiological accidents.
NRC staff also considered nonradiological impacts, such as transportation accidents, air quality and noise, chemicals and hazardous materials, and concluded that such impacts are negligible and will not result in adverse impacts. NRC staff also concludes that there are no environmental justice issues associated with the decommissioning of the York site, because there are no disproportionately high minority or low-income populations near the site. The licensee contacted the Pennsylvania Field Office of the U.S. Fish and Wildlife Service and determined that there are no endangered species on the York site.
Alternatives to the Proposed Action
The following alternatives, and the associated impacts and conclusions are described in the EA.
—Cleanup for Unrestricted Use and Shipment to an Approved Disposal Site;
—On-Site Storage at the York site; and,
—On-Site Disposal at the York site.
Based on NRC staff evaluation of the final DP for the York site, it was determined that the proposed decommissioning can be accomplished in compliance with NRC's public and occupational dose limits, effluent release limits, and residual radioactive material limits. In addition, the approval of the proposed decommissioning of the York site will not result in a significant adverse impact on the public health and the environment.
NRC staff concludes that there are no reasonably available alternatives to the licensee's preferred action that are obviously superior.
Agencies and Individuals Consulted
NRC staff consulted with the Pennsylvania Department of Environmental Protection (PADEP) in the preparation of this EA. PADEP provided comments and questions on the draft EA. Appropriate comments and responses to the questions were incorporated into the final EA.
Finding of No Significant Impact
Based upon the EA, the Commission concludes that the proposed action will not have a significant impact on the quality of the human environment. Accordingly, the Commission has determined not to prepare an Environmental Impact Statement for the proposed action.
For further details with respect to the proposed action, see: (1) Molycorp's license amendment application dated August 14, 1995, and Molycorp's supplemental information and responses to NRC comments dated November 24, 1999; and (2) the complete EA. These documents are available for public inspection at web site http://www.nrc.gov/NRC/ADAMS/index.html.Start Signature
Dated at Rockville, Maryland, this 3rd day of May 2000.
For the Nuclear Regulatory Commission.
Larry W. Camper,
Chief, Decommissioning Branch, Division of Waste Management, Office of Nuclear Material Safety and Safeguards.
[FR Doc. 00-11663 Filed 5-9-00; 8:45 am]
BILLING CODE 7590-01-P