ML15056A121

NRR E-mail Capture - Diablo Canyon, Unit 1 - RAIs for ASME Section XI ISI Program Request for Alternative RPV-U1- Extension to Allow Use of Alternate Reactor Inspection Interval Requirements

ML15056A121
Person / Time
Site:	Diablo Canyon
Issue date:	02/24/2015
From:	Siva Lingam Plant Licensing Branch IV
To:	Richardson M Pacific Gas & Electric Co
References
TAC MF4678
Download: ML15056A121 (2)

Text

NRR-PMDAPEm Resource From: Lingam, Siva Sent: Tuesday, February 24, 2015 4:10 PM To: mjrm@pge.com Cc: Oesterle, Eric; Young, Austin; Sheng, Simon; Soenen, Philippe R (PNS3@pge.com);

Schrader, Kenneth (KJSe@pge.com); cjm2@pge.com; adh6@pge.com

Subject:

Diablo Canyon, Unit 1 - RAIs for ASME Section XI ISI Program Request for Alternative RPV-U1- Extension to Allow Use of Alternate Reactor Inspection Interval Requirements (TAC No.

MF4678)

By letter dated August 18, 2014 (ADAMS Accession No. ML14230A618), Pacific Gas and Electric Company (PG&E, the licensee) requested approval from the Nuclear Regulatory Commission (NRC) to extend the Diablo Canyon Power Plant (DCPP) Unit 1 reactor vessel inspection interval from 10 to 20 years in accordance with WCAP-16168-NP-A, Revision 3, Risk-Informed Extension of the Reactor Vessel In-Service Inspection Interval. The proposed extension would be an alternative to the revised implementation plan, Pressurized-Water Reactor Owners Group (PWROG) Letter OG-10-238 (ADAMS Accession No. ML11153A033).

The NRC staff has reviewed the licensees proposal and determined that additional information is needed.

Please note the following official requests for additional information (RAIs), and provide your responses within 45 days or earlier from the date of this e-mail.

In accordance with Title 10 of the Code of Federal Regulations, Part 50, Section 50.55a(a)(3)(i) and the NRC safety evaluation approving the use of Westinghouse commercial atomic power (WCAP) 16168-NP-A, Revision 2, the NRC staff needs the following information to complete the review:

RAI - 1 Table 1, Critical Parameters for the Application of Bounding Analysis for DCPP Unit 1, states that DCPP Unit 1 is bounded by 7 heatup/cooldown cycles per year. Please cite the plant design basis for heatup/cooldown cycles per year.

RAI - 2 In Table 3, the licensees calculated T30, RTMAX-XX, and TWCF95-XX values were inconsistent with the calculations performed by the NRC staff. Please provide further detail on how T30 was calculated. In particular, please provide the Reactor Coolant System Temperature, Phosphorus [wt%], and Manganese [wt%]

values used to perform the calculations.

Please note that draft RAIs were sent to you on January 26, 2015, and you notified us that no clarification call is required.

Siva P. Lingam U.S. Nuclear Regulatory Commission Project Manager (NRR/DORL/LPL4-1)

Cooper Nuclear Station Diablo Canyon Nuclear Power Plant Location: O8-D5; Mail Stop: O8-B3 Telephone: 301-415-1564; Fax: 301-415-1222 E-mail address: siva.lingam@nrc.gov 1

Hearing Identifier: NRR_PMDA Email Number: 1897 Mail Envelope Properties (Siva.Lingam@nrc.gov20150224160900)

Subject:

Diablo Canyon, Unit 1 - RAIs for ASME Section XI ISI Program Request for Alternative RPV-U1- Extension to Allow Use of Alternate Reactor Inspection Interval Requirements (TAC No. MF4678)

Sent Date: 2/24/2015 4:09:41 PM Received Date: 2/24/2015 4:09:00 PM From: Lingam, Siva Created By: Siva.Lingam@nrc.gov Recipients:

"Oesterle, Eric" <Eric.Oesterle@nrc.gov>

Tracking Status: None "Young, Austin" <Austin.Young@nrc.gov>

Tracking Status: None "Sheng, Simon" <Simon.Sheng@nrc.gov>

Tracking Status: None "Soenen, Philippe R (PNS3@pge.com)" <PNS3@pge.com>

Tracking Status: None "Schrader, Kenneth (KJSe@pge.com)" <KJSe@pge.com>

Tracking Status: None "cjm2@pge.com" <cjm2@pge.com>

Tracking Status: None "adh6@pge.com" <adh6@pge.com>

Tracking Status: None "mjrm@pge.com" <mjrm@pge.com>

Tracking Status: None Post Office:

Files Size Date & Time MESSAGE 2277 2/24/2015 4:09:00 PM Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received: