ML20211J646

Forwards Response to NRC 990625 RAI Re NMPC Responses to GL 92-01,rev 1,supplement 1, Reactor Vessel Structural Integrity

ML20211J646
Person / Time
Site:	Nine Mile Point
Issue date:	08/30/1999
From:	Abbott R NIAGARA MOHAWK POWER CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-92-01, NMP1L-1460, TAC-MA1200, TAC-MA1201, NUDOCS 9909030218
Download: ML20211J646 (2)

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Richard B. Abbott Phone: 315.349.1812 Vice President Fax: 315.349.4417 NuclearEngineering August 30, 1999 NMPIL 1460 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 RE: Nine Mile Point Unit 1 Nine Mile Point Unit 2 Docket No. 50-220 Docket No. 50-410 DPR-63 NPF-69

Subject:

Response to Requestfor AdditionalInfonnation Regarding Generic Letter 92-01, Revision 1, Supplernent 1, " Reactor Vessel StructuralIntegrity"(TAC NOS. MA1200 and MA 1201)

Gentlemen:

On May 19,1995, the U. S. Nuclear Regulatory Commission (NRC) issued Generic Letter (GL) 92-01, Revision 1, Supplement 1, " Reactor Vessel Structural Integrity," to holders of nuclear power plant operating licenses. In that GL, the NRC staff requested that licensees review their reactor pressure vessel (RPV) structural integrity assessments in order to identify, l collect, and report any new data pertinent to the analysis of the structural integrity of their ,

RPVs. Also, the GL requested that licensees assess the impact of that data upon their RPV i integrity analyses relative to the requirements of Section 50.60 to Part 50 of Title 10 of the Code of Federal Regnhtions (10 CFR 50.60),10 CFR 50.61, Appendices G and H to 10 CFR Part 50 (which encompass pressurized thermal shock and upper shelf energy (USE) evaluations), and any potential impact on low temperature overpressure limits or pressure-temperature (P-T) limits.

l Niagara Mohawk Power Corporation (NMPC) has provided responses to GL 92-01, Revision 1, Supplement 1, and provided additional information requested by the NRC on May 29, 1998. The NRC acknowledged these correspondences on June 25,1999, and requested that;

1) NMPC should reconcile the difference between information contained in NMPC report NMEL-90001 and Combustion Engineering (CE) reports CE NPSD-1039, Revision 2, and CE NPSD-1119, Revision 1, and reassess the current P-T limits evaluation; and 2) NMPC should g review the data in the RPV Integrity Database (RVID) relative to Nine Mile Point (NMP1) and NMP2. This letter provides, pPC'3sponse to those requests.

The identity of the NMP1 surveillance program weld has been investigated and reconciled with the Combustion Engineering Owners Group (CEOG) reports. The result of an investigation, completed in January 1999, and coordinated with ABB Combustion Engineering and General Electric, confirms that the surveillance program weld was fabricated using weld wire heat W5214. This information was transmitted to the CEOG Reactor Vessel Working Group members by ABB Combustion Engineering in a letter dated February 26,1999. Accordingly, 9909030218 990830 PDR ADOCK 05000220 P PDR x 63, Lycoming. New York 13093 0063

• www.nimo.com

Pagc2o the best estimate values of 0.214 wt% Cu and 0.076 wt% Ni for the NMP1 vessel beltline weld fabricated with weld wire heat 1248 (Weld 1248) from NMPC's letter dated September 4,1998 should be reflected in the RVID. Since NMPC's P-T limits evaluation was correctly performed as reflected in our September 4,1998 submittal, there is no impact.

NMPC has reviewed the information in the RVID for NMP1 and NMP2. The following discrepancies are noted:

1) In the P-T Limits Summary Report for NMP1, the Chemistry Factor for Plate G-8-1 is listed as 225.94. The correct Chemistry Factor is 228.35 which is listed on Table 4-4 of NMPC's submittal (NMPIL 1377) dated November 6,1998,

2) The following Phosphorous and Sulfur percentages were provided by NMPC on July 2, 1992 (NMP2L 1347) which are not reflected in the P-T Limits Survey Report for NMP2.-

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l 4P7216(S) 0.011 0.011 4P7216(T) 0.011 0.012 4P7465(S) 0.010 0.013 4P7465(T) 0.012 0.014 SP5657(S) 0.015 0.021 4 5P5657(T) 0.016 0.020 SP6214B(S) 0.013 0.017 SP6214B(T) 0.011 0.014 Very truly yours, blbbY Richard B. Abbott ..

Vice President Nuclear Engineering L RBA/JMT/jb l

.xc: Mr. H. J. Miller, NRC Regional Administrator Mr. S. S. Bajwa, Section Chief PD-I, Section 1, NRR ,

Mr. G. K. Hunegs, NRC Senior Resident Inspector i Mr. D. S. Hood, Senior Project Manager, NRR Records Management