ML20212H140
| ML20212H140 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 09/21/1999 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20212H136 | List: |
| References | |
| NUDOCS 9909300221 | |
| Download: ML20212H140 (2) | |
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UNITED STATES
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NUCLEAR REGULATORY COMMISSION "E
WASHINGTON, D.C. 20555-0001
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.176 TO FACILITY OPERATING LICENSE NO. DPR-28 VERMONT YANKEE NUCLEAR POWER CORPORATION VERMONT YANKEE NUCLEAR POWER STATION DOCKET NO. 50-271
1.0 INTRODUCTION
By letter dated July 12,1999, the Vermont Yankee Nuclear Power Corporation (the licensee) submitted a request to amend the Vermont Yankee Nuclear Power Station (VY) Technical l
Specifications (TSs). The proposed amendment would revise the value for the minimum critical power ratio safety limit and delete the wording specifying the limit as cycle 20 values.
2.0 EVALUATION The licensee proposes changes to the value of the safety limit MCPR (SLMCPR) in TS 1.1.A.1 from 1.11 to 1.10 for two recirculation loop operation and from 1.13 to 1.12 for single recirculation loop operation when the reactor steam pressure is greater than 800 psia and core flow greater than 10 percent rated core flow. The removal of cycle-specific statements, "For the Cycle 20 core loading, the existence of " and " Core loading subsequent to Cycle 20 will require recalculation of the MCPR" are also proposed.
The licensee described the methodology used to calculate the SLMCPR value for the TS in the submittal. The Cycle 21 SLMCPR analysis was performed by GE Nuclear Energy (GENE) using the plant-specific and cycle-specific fuel and core parameters and NRC approved methodologies described in GESTAR-II (NEDE-24011-P-A-11, Sections 1.1.5 and 1.2.5),
NEDO-10958-A, January 1977 and Amendment 25 to GESTAR-II.
The staff has reviewed the justification fu U c SLMCPR value of 1.10 for two recirculation loop operation and 1.12 for single loop operation for Cycle 21 using the approach stated in Amendment 25 to GESTAR-11, NEDE-24011 and in NEDO-32601.
Based on our review of the submittal and the detailed summary results of the analysis for the Cycles 20 and 21 operation, the staff has concluded that the Cycle 21 SLMCPR analysis for VY using the plant-specific and cycle-specific calculation in conjunction with the approved method is recetable for VY. The Cycle 21 SLMCPR will ensure that 99.9 percent of the fuel rods in the core will not experience boiling transition which satisfies tne requirements of General i
Design Criterion 10 of Appendix A to 10 CFR Part 50 regarding acceptable fuel design limits.
The staff has concluded that the justification for the SLMCPR value of 1.10 for two loop and 1.12 for single loop for VY Cycle 21 operation is acceptable because approved methodologies l.
were used. The proposed removal of cycle-specific statements is also acceptable because the i
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, analysis is already performed using plant specific and cycle-specific parameters in accordance with the procedures specified in Amendment 25 to GESTAR-il, NEDE-2401-P-A.
3.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Vermont State official was notified of the proposed issuance of the amendment. The State official had no comments.
450 ENVIRONMENTAL CONSIDERATION The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no significant increase in amounts, and no significant change in the types of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (64 FR 40910).
Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
5.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the p. posed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor: T. Huang
. Date: September 21, 1999