ML20087K933
| ML20087K933 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 08/17/1995 |
| From: | Olivier L BOSTON EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| BECO-LTR-#95-08, BECO-LTR-#95-8, GL-92-01, GL-92-1, NUDOCS 9508240259 | |
| Download: ML20087K933 (4) | |
Text
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GL 92-02, R;v.1, Supp.1 Boston Edison Pdgrim Nuclear Power station Rocky Hdi Road Plymouth, Massachusetts 02300 August 17. 1995 L J. Olivier BECo Ltr. #95-082 Vice Pres 4ent Nuclear Operations and Station Director U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Docket No. 50-293 License No. DPR-35 l
Generic Letter 92-01. Rev.1. Supp.1
" Reactor Vessel Structural Intearity".
l Enclosed is the Boston Edison Company (BECo) response to the NRC request for information j'
contained in Generic Letter 92-01, Revision 1, Supplement 1, " Reactor Vessel Structural Integrity",
dated May 19,1995.
The supplement required all addressees to:"...... identify, collect, and report any new data pertinent to analeris of structural integrity of their reactor pressure vessels (RPVs) and to assess the impact of that (s.a on their RPV integrity analysis relative to the requirements of section 50.60 of Title 10 of the Code of Federal Regulations (10 CFR 50.60),10 CFR 50.61, Appendices G and H to 10 CFR Part 50, which encompass pressurized thermai shock (PTS) and upper shelf energy (USE) evaluations and any potential impact on low temperature overpressure (LTOP) limits or pressure-temperature (P-T) limits."
l BECo's Pilgrim Nuclear Power Plant (PNPS) is a boiling water reactor (BWR) and, as referenced in l:
the generic letter, is not subject to either PTS or LTOP limits.
l In addition to the enclosed response, BECo endorses the Boiling Water Reactor Vessel & Internals Project (BWRVIP) Action Plan for RPV Integrity Data as described in their response letter to the NRC, dated August 10,1995.
Oh
. J. Olivier
Enclosure:
BECo Response to GL 92-01, Rev.1, Supp.1 Commonwealth of Massachusetts)
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County of Plymouth
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i Then personally appeared before me, L. J. Olivier, who being duly swom, did state that he is Vice President - Nuclear Operations and Station Director of Boston Edison Company and that he is duly,,7,
authorized to execute and file the submittal contained herein in the name and on behalf of Bostorra.hy.
Edison Company and that the statements in said submittal are true to the best of his knowl f
belief 5
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'.[Y My commission expires: MAR 4 - 1999 6
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9500240259 950817 GERALD G. WHITNEY, Notary Public i-u DR ADOCK 0500 3
My C0mmiSsion Expiros Much 4,1999 h. MY
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- Mr. R Eaton, Project Manager -
1 Division of Recctor Projects - 1/11 Mail Stop: 1401.
U. S. Nuclear Regulatory Commission -
i 1 White Flint North-11555 Rockville Pike Rockville, MD 20852
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U.S. Nuclear Regulatory Commission
-i Region 1 475 Allendale Road King of Prussia, PA 19406 -
Senior Resident inspector Pilgrim Nuclear Power Station t
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t Bo: tin Edison C mpany Response to Generic Letter 92-01. Revision 1, Supplement 1 Addressees of this generic letter are required to provide the following information within 90 days of the publication date of the generic letter:
(1)
Provide a description of those actions taken or planned to locate all data relevant to the determination of RPV integrity, or an explanation of why the existing data base is considered complete as previously submitted.
Addressees of this generic letter are also required to provide the following information within 6 months of the publication date of the genericletter:
(2)
Provide an assessment of any change in best estimate chemistry based on consideration of all relevant data.
(3)
Provide a determination of the need for use of the ratio procedure in accordance with the established Position 2.1 of Regulatory Guide 1.99, Revision 2, for those licensees that use surveillance data to provide a basis for the RPV integrity evaluation.
(4)
Provide a written report providing any newly acquired data as specified above and (1) the results of any necessary revisions to the evaluation of RPV integrity in accordance with the requirements of 10 CFR 50.60,10 CFR 50.61, Appendices G and H to 10 CFR Part 50, and any potential impact on the LTOP or P-T limits in the technical specifications or (2) a certification that previously submitted evaluations remain valid. Revised evaluations and certifications should include consideration of Position 2.1 of Regulatory Guide 1.99, Revision 2, as applicable, and any new data.
Boston Edison Company (BECo) provides the following response to Question 1:
BECo has participated in the Combustion Engineering Owners Group (CEOG) since its inception in 1992 and has been active in gathering Pilgrim RPV plate and weld chemical and physical property data for the past three years. Both BECo and CE conducted a search of their records and retrieved the known documentation that references the Pilgrim RPV beltline plate and weld material. This search continues through our participation in the CEOG.
The BWRVIP letter, dated August 10, 1995, provided the "BWRVIP Action Plan for RPV Integrity Data", We endorse this action plan and, in parallel, will focus on obtaining data regarding the Pilgrim RPV deposited beltline weld chemistries. The ideal would be to find surveillance capsule data relevant to the Pilgrim RPV.
BECo will continue to work with the CEOG to determine the weld deposit data for the beltline welds. Other data bases (such as EPRI, ORNL, and GE) that are not part of the CEOG effort are also being reviewed by BECo to gather and verify chemical and physical data for the Pilgrim RPV.
BECo representatives attended the NRC / NEl Workshop on RPV Integrity issues held on July 11 to 13,1995. Subsequent to that workshop, BECo obtained the NRC reactor vessel integrity data base (RVID) in digital format for review. This review is currently incomplete. A preliminary review of the RVlD indicates inconsistencies exist among Pilgrim's " sister plant" data regarding identified chemistry factors. We will monitor the BWRVIP effort to resolve these inconsistencies.
The existing CEOG data base for Pilgrim does not have weld deposit data for the limiting weld in the Pilgrim reactor pressure vessel. Calculations performed for BECo, using Regulatory
Guide (RG) 1.99, R; vision 2 guidelines, conservctiv;ly used th) upper bound chemistry f;ctor o
(CF) of 272. This CF corresponds to 0.35 % Cu and 1.0 %Ni. A review of data for welds similar tg limiting weld, [(1338 A, B, C, Filler 27204/12008 (Tandem Arc), wire type B-4 (Mod), flux type Linde 1092, flux lot 3774)), shows the CF of 272 is bounding and conservative.
BECo is providing the following preliminary response to Questions 2,3, and 4 of the Generic Letter.
- (2, 3, & 4)
The Boiling Water Reactor Vessel & Intemals Project (BWRVIP) response to GL 92-01, Rev.1, Supp.1, dated 8/10/95, indicates in the "BWRVIP Action Plan for RPV Integrity Data" it will take 24 months to gather all remaining known data that is relevant for Pilgrim. BECo supports the BWRVIP action plan as stated. The data search, supporting the BWRVIP action plan, is expected to provide confirmation of the conservative upper bound assumption discussed above. If any valid information is found during the data search that invalidates the upper bound assumption, the NRC will be informed immediately.
BECo would like to take this opportunity to correct an inconsistency found in the Reactor Vessel Integrity Database (RVID) as it pertains to the Pilgrim RPV.
BECo does not concur with the RVID data for Pilgrim Weld initial Reference Nil Ductility Temperature (Rtndt) value of 0 Deg. F. BECo. believes the correct temperature is -48 Deg. F.
BECo. provided the NRC with documentation that supports this position ( see Teledyne Technical Report # TR-7407, dated April 16,1991) which states:
"Charpy data obtained subsequently from Combustion Engineering Weld Data Report for the Pilgrim RPV beltline welds indicate an initial Rtndt as low as -50 Deg. F. This value
( 50 Deg. F = Tcv-60 Deg F) is based on Charpy energies obtained for the 10 Deg F (Tcv) tests ranging from 49 to 63 foot-pounds with and average of 59 foot-pounds."
The value of -48 Deg F is obtained by using the GE method that requires the Rtndt value must be increased by 2 Deg F. for every foot-pound of Charpy energy measured less than the 50 foot-pound reference value.
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