ML010650229
| ML010650229 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee  |
| Issue date: | 04/02/2001 |
| From: | Pulsifer R NRC/NRR/DLPM/LPD1 |
| To: | Balduzzi M Vermont Yankee |
| Pulsifer R M, NRR/DLPM, 415-3016 | |
| References | |
| TAC MB0763 | |
| Download: ML010650229 (8) | |
Text
April 2, 2001 Mr. Michael A. Balduzzi Vice President, Operations Vermont Yankee Nuclear Power Corporation 185 Old Ferry Road P.O. Box 7002 Brattleboro, VT 05302-7002
SUBJECT:
VERMONT YANKEE NUCLEAR POWER STATION - ENVIRONMENTAL ASSESSMENT AND FINDING OF NO SIGNIFICANT IMPACT FOR AN EXEMPTION FROM THE REQUIREMENTS OF 10 CFR PART 50, APPENDIX G (TAC NO. MB0763)
Dear Mr. Balduzzi:
Enclosed is a copy of the Environmental Assessment and Finding of No Significant Impact related to your application for an exemption from the requirements of Title 10 of the Code of Federal Regulations, (10 CFR) Part 50, Appendix G for the Vermont Yankee Nuclear Power Station (Vermont Yankee). This action is in response to your letter dated December 19, 2000, that submitted new pressure-temperature (P-T) limits for Vermont Yankee. The new P-T limits were developed using the methodologies in the American Society of Mechanical Engineers (ASME) Code Case N-640, Alternative Reference Fracture Toughness for Development of P-T Limit Curves for ASME Section XI, Division 1, instead of the methodologies in 10 CFR Part 50, Appendix G.
An exemption request for Code Case N-588, Alternative to Reference Flaw Orientation of Appendix G for Circumferential Welds in the Reactor Vessels, was also submitted in a letter dated December 19, 2000; however, it was subsequently withdrawn by a letter dated February 13, 2001.
The assessment is being forwarded to the Office of the Federal Register for publication.
Sincerely,
/RA/
Robert M. Pulsifer, Project Manager, Section 2 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-271
Enclosure:
Environmental Assessment cc w/encl: See next page
April 2, 2001 Mr. Michael A. Balduzzi Vice President, Operations Vermont Yankee Nuclear Power Corporation 185 Old Ferry Road P.O. Box 7002 Brattleboro, VT 05302-7002
SUBJECT:
VERMONT YANKEE NUCLEAR POWER STATION - ENVIRONMENTAL ASSESSMENT AND FINDING OF NO SIGNIFICANT IMPACT FOR AN EXEMPTION FROM THE REQUIREMENTS OF 10 CFR PART 50, APPENDIX G (TAC NO. MB0763)
Dear Mr. Balduzzi:
Enclosed is a copy of the Environmental Assessment and Finding of No Significant Impact related to your application for an exemption from the requirements of Title 10 of the Code of Federal Regulations, (10 CFR) Part 50, Appendix G for the Vermont Yankee Nuclear Power Station (Vermont Yankee). This action is in response to your letter dated December 19, 2000, that submitted new pressure-temperature (P-T) limits for Vermont Yankee. The new P-T limits were developed using the methodologies in the American Society of Mechanical Engineers (ASME) Code Case N-640, Alternative Reference Fracture Toughness for Development of P-T Limit Curves for ASME Section XI, Division 1, instead of the methodologies in 10 CFR Part 50, Appendix G.
An exemption request for Code Case N-588, Alternative to Reference Flaw Orientation of Appendix G for Circumferential Welds in the Reactor Vessels, was also submitted in a letter dated December 19, 2000; however, it was subsequently withdrawn by a letter dated February 13, 2001.
The assessment is being forwarded to the Office of the Federal Register for publication.
Sincerely,
/RA/
Robert M. Pulsifer, Project Manager, Section 2 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-271
Enclosure:
Environmental Assessment cc w/encl: See next page DISTRIBUTION:
PUBLIC PDI-2 R/F OGC ACRS C. Carpenter E. Adensam T. Clark G. Meyer, RI J. Clifford R. Pulsifer Accession Number: ML010650229 OFFICE PM:LPD1 LA:LPD1 RGEB OGC SC:LPD1 NAME RPulsifer MO'Brien for BZalcman for RHoefling JClifford TClark CCarpenter DATE 3/19/01 03/15/01 3/15/01 3/28/01 3/29/01 OFFICIAL RECORD COPY
Vermont Yankee Nuclear Power Station cc:
Regional Administrator, Region I Mr. Raymond N. McCandless U. S. Nuclear Regulatory Commission Vermont Department of Health 475 Allendale Road Division of Occupational King of Prussia, PA 19406 and Radiological Health 108 Cherry Street Mr. David R. Lewis Burlington, VT 05402 Shaw, Pittman, Potts & Trowbridge 2300 N Street, N.W. Mr. Gautam Sen Washington, DC 20037-1128 Licensing Manager Vermont Yankee Nuclear Power Ms. Christine S. Salembier, Commissioner Corporation Vermont Department of Public Service 185 Old Ferry Road 112 State Street P.O. Box 7002 Montpelier, VT 05620-2601 Brattleboro, VT 05302-7002 Mr. Michael H. Dworkin, Chairman Resident Inspector Public Service Board Vermont Yankee Nuclear Power Station State of Vermont U. S. Nuclear Regulatory Commission 112 State Street P.O. Box 176 Montpelier, VT 05620-2701 Vernon, VT 05354 Chairman, Board of Selectmen Director, Massachusetts Emergency Town of Vernon Management Agency P.O. Box 116 ATTN: James Muckerheide Vernon, VT 05354-0116 400 Worcester Rd.
Framingham, MA 01702-5399 Mr. Richard E. McCullough Operating Experience Coordinator Jonathan M. Block, Esq.
Vermont Yankee Nuclear Power Station Main Street P.O. Box 157 P. O. Box 566 Governor Hunt Road Putney, VT 05346-0566 Vernon, VT 05354 G. Dana Bisbee, Esq.
Deputy Attorney General 33 Capitol Street Concord, NH 03301-6937 Chief, Safety Unit Office of the Attorney General One Ashburton Place, 19th Floor Boston, MA 02108 Ms. Deborah B. Katz Box 83 Shelburne Falls, MA 01370
7590-01-P UNITED STATES NUCLEAR REGULATORY COMMISSION VERMONT YANKEE NUCLEAR POWER CORPORATION DOCKET NO. 50-271 VERMONT YANKEE NUCLEAR POWER STATION 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 Title 10 of the Code of Federal Regulations (10 CFR)
Part 50, Appendix G for Facility Operating License No. DPR-28, issued to Vermont Yankee Nuclear Power Corporation (VYNPC, or the licensee) for operation of the Vermont Yankee Nuclear Power Station (Vermont Yankee), located in Windham County, Vermont.
ENVIRONMENTAL ASSESSMENT Identification of the Proposed Action:
Title 10 of the Code of Federal Regulations, Part 50, Appendix G, requires that pressure-temperature (P-T) limits be established for reactor pressure vessels (RPVs) during normal operating and hydrostatic or leak rate testing conditions. Specifically, 10 CFR Part 50, Appendix G, states, The appropriate requirements on both the pressure-temperature limits and the minimum permissible temperature must be met for all conditions. Appendix G of 10 CFR Part 50 specifies that the requirements for these limits are the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code),Section XI, Appendix G Limits.
The proposed action would exempt Vermont Yankee from application of specific requirements of 10 CFR Part 50, Appendix G, and substitute use of ASME Code Case N-640.
Code Case N-640 permits the use of an alternate reference fracture toughness (KIC fracture toughness curve instead of KIa fracture toughness curve) for reactor vessel materials in determining the P-T limits. Since the KIC fracture toughness curve shown in ASME Section XI, Appendix A, Figure A-2200-1 (the KIC fracture toughness curve) provides greater allowable fracture toughness than the corresponding KIa fracture toughness curve of ASME Section XI, Appendix G, Figure G-2210-1 (the KIa fracture toughness curve), using Code Case N-640 for establishing the P-T limits would be less conservative than the methodology currently endorsed by 10 CFR Part 50, Appendix G, and an exemption to apply the Code Case would be required by 10 CFR 50.60.
The proposed action is in accordance with the licensee's application for exemption dated December 19, 2000.
The Need for the Proposed Action:
ASME Code Case N-640 is needed to revise the method used to determine the reactor coolant system (RCS) P-T limits, since continued use of the present curves unnecessarily restricts the P-T operating window. Since the RCS P-T operating window is defined by the P-T operating and test limit curves developed in accordance with the ASME Section XI, Appendix G procedure, continued operation of Vermont Yankee with these P-T curves without the relief provided by ASME Code Case N-640 would unnecessarily require the RPV to maintain a high temperature during the pressure tests. Consequently, steam leak hazards would continue to be one of the safety concerns for personnel conducting inspections in the primary containment.
Implementation of the proposed P-T curves, as allowed by ASME Code Case N-640, does not
significantly reduce the margin of safety and would eliminate steam vapor hazards by allowing inspections in primary containment to be conducted at lower coolant temperature.
In the associated exemption, the staff has determined that, pursuant to 10 CFR 50.12(a)(2)(ii), the underlying purpose of the regulation will continue to be served by the implementation of this Code Case.
Environmental Impacts of the Proposed Action:
The NRC has completed its evaluation of the proposed action and concludes that the exemption described above would provide an adequate margin of safety against brittle failure of the Vermont Yankee reactor vessel.
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 nonradiological environmental impacts, the proposed action does not involve any historic sites. It does not affect nonradiological plant effluents and has no other environmental impacts. Therefore, there are no significant nonradiological 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:
This action does not involve the use of any resources not previously considered in the Final Environmental Statement for the Vermont Yankee Nuclear Power Station dated December 1974.
Agencies and Persons Consulted:
In accordance with its stated policy, on March 3, 2001, the staff consulted with the Vermont State official, William K. Sherman of the Department of Public Service, 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 December 19, 2000. Documents may be examined, and/or copied for a fee, at the NRCs 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).
Dated at Rockville, Maryland, this 2nd day of April 2001.
FOR THE NUCLEAR REGULATORY COMMISSION
/RA/
Robert Pulsifer, Project Manager, Section 2 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation