ML20044G152
| ML20044G152 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 05/21/1993 |
| From: | Link B WISCONSIN ELECTRIC POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| CON-NRC-93-67 GL-92-01, GL-92-1, VPNPD-93-108, NUDOCS 9306020092 | |
| Download: ML20044G152 (2) | |
Text
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!Bectnc POWER COMPANY 231 w Megm Po w 2045. Mawaukee. wi 53201
[41412202345 VPNPD-93-108 NRC-93-67 May 21, 1993 Document Control Desk U.S.
NUCLEAR REGULATORY COMMISSION Mail Station F1-137 Washington, DC 20555 Gentlemen, DOCKETS 50-266 AND 50-301 REACTOR VESSEL LOW UPPER-SHELF TOUGHNESS FRACTURE MECHANICS ANALYSIS LEVEL C AND D SERVICE LOADL POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 Nuclear Regulatory Commission (NRC) Generic Letter (GL) 92-01,
" Reactor Vessel Structural Integrity," dated March 6, 1992, was issued to obtain information from licensees to enable the NRC to assess compliance with regulatory requirements and commitments regarding reactor vessel integrity.
Our response to Generic Letter 92-01 was provided to the NRC on June 25, 1992 In that response, Wisconsin Electric Power Company stated that an analysis' would be conducted by the end of 1993 for the Point Beach Nuclear Plants to demonstrate adequate margins of safety with respect to that required in 10 CFR 50 Appendix G,
" Fracture Toughness Requirements."
This submittal discusses'the results of this analysis for level C and D service loads.
The B&W Owners Group Reactor Vessel Working Group, under the direction of Wisconsin Electric and other member utilities, developed Report BAW-2178P, " Low Upper-Shelf Toughness Fracture' Mechanics Analysis of Reactor Vessels of B&W Owners Reactor Vessel
. Working Group for Level C & D Service Loads."
This report was submitted to the NRC by B&W Nuclear Service Company on March 9, 1993.
For analysis convenience, BAW-2178P performed a bounding analysis of low upper-shelf toughness reactor vessels.
After examining all the design basis transients for Level C and D service loads for all-member utilities, the limiting. transient was. selected for each level of service load, and was'used for the fracture mechanics evaluation.
Additionally, bounding material properties were used
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Document Control Desk May 21, 1993 Page 2 in the analysis.
We have reviewed data contained in BAW-2178P with respect to Point Beach Huclear Plant, Units 1 and 2, and find it r
acceptable.
As reported in BAW-2178P, this bounding analysis demonstrates the adequacy of the margin of safety for continued operation of the Point Beach reactor vessels beyond the end of the existing license.
For Level A and B service loads, the B&W Owners Group Reactor Vessel Working Group selected two lead plants to perform the fracture mechanics evaluation.
The results from these analyses are reported in BAW-2118P, " Low Upper-Shelf Toughness Fracture Analysis of Reactor Vessels of Turkey Point Units 3 and 4 for Load Level A &
l B Conditions," and BAW-2148P, " Low Upper-Shelf Toughness Fracture Analysis of Reactor Vessels of Zion Units 1 and-2 for Load Level A
& B Conditions."
These reports were submitted to the NRC-in November 1991 and September 1992, respectively.
Both of-these analyses indicate that adequate margins of safety exist for. Level A and B service loads for their respective plants.
We have. reviewed BAW-2118P and BAW-2148P and believe that both Point-Beach reactor vessels are bounded by the analyses.
Furthermore, on September 10, 1992, the B&W Owners Group Reactor Vessel Working Group sent a letter to the Materials and Chemical' Engineering Branch of the NRC in which it stated that an assessment was performed indicating that the two lead plant analyses bound the rest of the owners group's reactor vessels.
We believe that based on the analysis presented in BAW-2178P, Point Beach Nuclear Plant Units 1 and 2 have adequate margins of safety for Level C and D service load conditions.
Additionally, based on the result from the analyses reported in BAW-2118P and BAW-2148P, we believe that adequate margins of safety exist for Level A & B service load conditions for Point Beach Nuclear Plant Units 1 and 2.
If you have any questions or require additional information, please contact us.
Sincerely, j77_[ue LvL, i
[N./.
Bob k
Vice President Nuclear Power GLM/jg nc:
NRC Regional Administrator, Rerion III NRC Resident Inspector
.