DCL-15-075, Relief Request REP-SI - Supplement

Relief Request REP-SI - Supplement

ML15169A368
Person / Time
Site:	Diablo Canyon
Issue date:	06/18/2015
From:	Allen B Pacific Gas & Electric Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
DCL-15-075
Download: ML15169A368 (4)

Text

Pacific Gas and Electric Company Barry S. Allen Diablo Canyon Power Plant Vice President, Nuclear Services Mail Code 104/6 P. 0. Box 56 Avila Beach, CA 93424 June 18, 2015 805.545.4888 Internal: 691.4888 PG&E Letter DCL-15-075 Fax: 805.545.6445 U.S. Nuclear Regulatory Commission 10 CFR 50.55a ATTN: Document Control Desk Washington, DC 20555-0001 Docket No. 50-275, OL-DPR-80 Docket No. 50-323, OL-DPR-82 Diablo Canyon Power Plant Unit 1 and Unit 2 Relief Request REP-SI - Supplement

References:

1. PG&E Letter DCL-14-060, "ASME Section Xllnservice Inspection Program Request for Alternative REP-SI: Proposed Alternative to Requirements for Repair/Replacement Activities for Certain Safety Injection Pump Welded Attachments," dated July 21, 2014 (ML14202A613)

2. NRC Letter, "Diablo Canyon Power Plant, Units 1 and 2 - lnservice Inspection Program Request for Alternative REP-SI: Proposed Alternative to Requirements for Repair and Replacement Activities for Certain Safety Injection Pump Welded Attachments (TAC Nos. MF4476 and MF4477)," dated December 23, 2014

3. PG&E Letter DCL-15-021, "Response to NRC Request for Additional Information Regarding Relief Request REP-SI," dated February 5, 2015 (ML15036A606)

4. PG&E Letter DCL-15-038, "Response to NRC Request for Additional Information Regarding Relief Request REP-SI- Part 2," dated March 30, 2015 (ML15089A594)

5. Teleconference with NRC, "Diablo Canyon RR REP-SI, Sl Pump Welded Attachments - Discussion of Making Commitments versus Alternative Requests (TAC Nos. MF4476 and MF4477)," dated June 4, 2015

Dear Commissioners and Staff:

In Reference 1, Pacific Gas and Electric Company (PG&E) submitted a Relief A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway

• Diablo Canyon

• Palo Verde

• Wolf Creek

Document Control Desk PG&E Letter DCL-15-075 June 18, 2015 Page2 Request for alternative REP-SI for Diablo Canyon Power Plant Units 1 and 2 for NRC approval.

In Reference 2, the NRC Staff provided a request for additional information (RAI) via letter dated December 23, 2014. In References 3 and 4, PG&E submitted responses to the RAI. In addition, PG&E submitted Revision 2 of the Relief Request for NRC approval, in Reference 4.

On June 4, 2015, PG&E discussed with NRC Staff (Reference 5), revising Section 5.6, "Commitments for Visual Examination and Nondestructive Examination," of the proposed Relief Request from Reference 4. A revised Section 5.6, "Proposed Alternative Visual and Nondestructive Examinations,"

converts the previously proposed regulatory commitments into proposed alternative examinations. The proposed revision also makes it clear that approval for proposed alternatives is being requested. The revised version of Section 5.6 is included in the Enclosure to this letter.

This communication does not contain regulatory commitments (as defined by NEI 99-04).

If you have any questions or require additional information, please contact Mr. Hossein Hamzehee at (805) 545-4720.

Sincerely, Ba~~n 5. ;fa-Vice President, Nuclear Services rntt/4231/50600119 Enclosure cc: Diablo Distribution cc/enc: Marc L. Dapas, NRC Region IV Administrator Thomas R. Hipschman, NRC Senior Resident Inspector Siva P. Lingam, NRC Project Manager Gonzalo L. Perez, Branch Chief, California Department of Public Health State of California, Pressure Vessel Unit A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway

• Diablo Canyon

• Palo Verde

• Wolf Creek

Enclosure PG&E Letter DCL-15-075 Revised Section 5.6 of Relief Request REP-SI, Revision 2 Proposed Alternative In Accordance with 10 CFR 50.55a(z)(2)

-Compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety-

Reference:

1. PG&E Letter DCL-15-038, "Response to NRC Request for Additional Information Regarding Relief Request REP-SI - Part 2," dated March 30, 2015 (ML15089A594)

In Reference 1, Pacific Gas and Electric Company (PG&E) submitted, "Relief Request REP-S I, Revision 2," for NRC approval. Section 5.6 of the Relief Request has been revised to make it clear that approval for proposed alternatives is being requested. The revised Section 5.6, "Proposed Alternative Visual and Nondestructive Examinations," that is presented in this Enclosure replaces the previous Section 5.6, "Commitments for Visual Examination and Nondestructive Examination," in Reference 1, in its entirety.

5.6 Proposed Alternative Visual and Nondestructive Examinations To provide continued assurance of the integrity of the affected safety injection (SI) pump welds, the following alternative surveillance tests and nondestructive examinations (NDE) are proposed.

5.6.1 Alternative Visual Examinations for Leakage Surveillance test procedures (STPs) for quarterly testing of Sl pumps 1-1, 1-2, and 2-1 will be revised (within 90 days after NRC approval) to require the test performer to visually examine the subject vent and drain connections for evidence of external leakage during all future tests.

Leakage at these locations would be readily detectable due to accumulation of boric acid crystals at the leak site.

5.6.2 Alternative Periodic Surface Nondestructive Examinations Liquid penetrant examinations conducted in December 2013 demonstrated absence of pre-existing outer-diameter (OD) surface flaws in support of the OD flaw growth analysis. The lnservice Inspection (lSI)

Program Plan for the fourth lSI Interval is being prepared to require NDE 1 of 2

Enclosure PG&E Letter DCL-15-075 surface examination (liquid penetrant method) of the Sl pump vent and drain connection welds where the carbon content of the 41 OSS base metal exceeds 0.08 percent or is not measurable due to insufficient access for Arc-Met testing. The alternative liquid penetrant examinations will be performed on an lSI periodic basis (once every 40 months), with the interval starting May 7, 2015, for Unit 1 and March 13, 2016, for Unit 2. The alternative liquid penetrant NDE examinations on an lSI periodic basis will provide continued assurance that no flaws exist at these locations. These alternative examinations will be included in all future lSI interval Program Plans for the subject pumps.

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