01-20235. Dominion Nuclear Connecticut, Inc., et al.; Millstone Nuclear Power Station, Unit No. 3 Environmental Assessment and Finding of No Significant Impact

The U.S. Nuclear Regulatory Commission (NRC) is considering issuance of an exemption from certain requirements of Appendix G to Part 50 of Title 10 of the Code of Federal Regulations (10 CFR part 50) for Facility Operating License No. NPF-49, issued to Dominion Nuclear Connecticut, Inc. (the licensee), for operation of the Millstone Nuclear Power Station, Unit No. 3 (MP3), located in Waterford, Connecticut. Therefore, as required by 10 CFR 50.21, the NRC is issuing this environmental assessment and finding of no significant impact.

Environmental Assessment

Identification of the Proposed Action

The proposed action would exempt the licensee from certain requirements of Appendix G to 10 CFR part 50 to allow the application of the methodology approved for determining the pressure-temperature (P-T) limit curves in the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code), Section XI, Code Case N-640 entitled, “Alternate Reference Fracture Toughness for Development of P-T Curves for ASME Section XI, Division I.”

The proposed action is in accordance with the licensee's application for an exemption dated April 23, 2001, as supplemented by letter dated June 25, 2001.

The Need for the Proposed Action

The proposed action would modify the currently approved methodology for P-T limit calculations to incorporate the methodology approved for use in Code Case N-640. Code Case N-640 allows the use of the K_IC fracture toughness curve instead of the K_IA fracture toughness curve, as required by Appendix G to Section XI, for determining P-T limits for reactor pressure vessel (RPV) materials. The exemption is needed because Code Case N-640 uses this modification in the approved methodology in Appendix G of Section XI in determining P-T limits. The proposed action also supports the licensee's application for a license amendment, dated April 23, 2001, to revise the Technical Specifications (TSs) P-T limits.

The staff has determined that, pursuant to 10 CFR 50.12(a)(2)(ii), the underlying purpose of the regulation to protect the integrity of the reactor coolant pressure boundary will continue to be served by the implementation of the code case.

Environmental Impacts of the Proposed Action

The NRC has completed its evaluation of the proposed action and concludes that the exemption and implementation of the proposed alternative described above would provide an adequate margin of safety against brittle failure of the RPV at MP3.

The proposed action will not significantly increase the probability or consequences of accidents, no changes are being made in the types of any effluents that may be released off site, and there is no significant increase in occupational or public radiation exposure. Therefore, there are no significant radiological environmental impacts associated with the proposed action.

With regard to potential non-radiological impacts, the proposed action does not have a potential to affect any historic sites. It does not affect non-radiological plant effluents and has no other environmental impact. Therefore, there are no significant non-radiological environmental impacts associated with the proposed action.

Accordingly, the NRC concludes that there are no significant environmental impacts associated with the proposed action.

Alternatives to the Proposed Action

As an alternative to the proposed action, the staff considered denial of the proposed action (i.e., the “no-action” alternative). Denial of the application would result in no change in current environmental impacts. The environmental impacts of the proposed action and the alternative action are similar.

Alternative Use of Resources

The action does not involve the use of any different resources than those previously considered in the Final Environmental Statement for MP3, dated December 1984.

Agencies and Persons Consulted

In accordance with its stated policy, on June 20, 2001, the staff consulted with the Connecticut State official, Michael Firsick of the Department of Environmental Protection, regarding the environmental impact of the proposed action. The State official had no comments.

Finding of No Significant Impact

On the basis of the environmental assessment, the NRC concludes that the proposed action will not have a significant effect on the quality of the human environment. Accordingly, the NRC has determined not to prepare an environmental impact statement for the proposed action.

For further details with respect to the proposed action, see the licensee's letter dated April 23, 2001, as supplemented by letter dated June 25, 2001. Documents may be examined, and/or copied for a fee, at the NRC's Public Document Room, located at One White Flint North, 11555 Rockville Pike (first floor), Rockville, Maryland. Publicly available records will be accessible electronically from the ADAMS Public Library component on the NRC Web site, http: /www.nrc.gov (the Electronic Reading Room). If you do not have access to ADAMS or if there are problems in accessing the documents located in ADAMS, contact the NRC Public Document Room (PDR) Reference staff at 1-800-397-4209, or 301-415-4737, or by e-mail at [e-mail].

Dated at Rockville, Maryland, this 8th day of August 2001.

For the Nuclear Regulatory Commission.

Victor Nerses, Sr.,

Project Manager, Section 2, Project Directorate I, Division of Licensing Project Management, Office of Nuclear Reactor Regulation.