ML18023A715

Residual Heat Removal Suction Weld Joint Flaw Evaluation (CAC No. MG0140; EPID L-2017-LRO-0026)

ML18023A715
Person / Time
Site:	Diablo Canyon
Issue date:	01/26/2018
From:	Balwant Singal Plant Licensing Branch IV
To:	Welsch J Pacific Gas & Electric Co
Singal B, 301-415-3016
References
CAC MG0140, EPID L-2017-LRO-0026
Download: ML18023A715 (3)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, O.C. 20555-0001 January 26, 2018 Mr. James M. Welsch Vice President, Nuclear Generation and Chief Nuclear Officer Pacific Gas and Electric Company Diablo Canyon Power Plant P.O. Box 56, Mail Code 104/6 Avila Beach, CA 93424

SUBJECT:

DIABLO CANYON POWER PLANT, UNIT 1 -RESIDUAL HEAT REMOVAL SUCTION WELD JOINT FLAW EVALUATION (CAC NO. MG0140; EPID L-2017-LR0-0026)

Dear Mr. Welsch:

By letter dated August 17, 2017 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML17229B617), Pacific Gas and Electric Company (PG&E, the licensee), submitted a flaw evaluation of the Diablo Canyon Power Plant (DCPP), Unit 1, residual heat removal (RHR) suction weld joint, WIB-228. The submittal was made in accordance with subparagraph IWB-3134(b) of the American Society of Mechanical Engineer's Boiler and Pressure Vessel Code (ASME Code),Section XI, 2007 Edition through 2008 Addenda.

Section XI of the ASME Code has requirements for evaluation of flaws identified during inservice inspections. Specifically, flaws that exceed the applicable acceptance criteria are acceptable for continued service without a repair/replacement activity if an analytical evaluation, as described in paragraph IWB-3600, is performed and found acceptable. Furthermore, subparagraph IWB-3134(b) requires that analytical evaluation of examination results, as required by subparagraph IWB-3132.3, shall be submitted to the regulatory authority having jurisdiction at the plant (i.e., U.S. Nuclear Regulatory Commission (NRC)).

The NRC staff reviewed the flaw evaluation report for weld joint WIB-228 for DCPP, Unit 1, and did not identify any questions or concerns.

J. Welsch If you have any questions, please contact me at 301-415-3016 or via e-mail at Balwant. Singal@nrc.gov.

Sincerely, ES~.,- la-81~~

Balwant K. Singal, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-275 cc: Listserv

ML18023A715 OFFICE NRR/DORL/LPL4/PM NRR/DORL/LPL4/LA NRR/DMLR/MPHB/BC NAME BSingal PBlechman DAIiey DATE 01/23/2018 01/23/2018 01/23/2018 OFFICE NRR/DORL/LPL4/BC NRR/DORL/LPL4/PM NAME RPascarelli BSingal DATE 01/26/2018 01/26/2018