ML033440288

MB6821, RP-06, Rev. 1, Draft RAIs on 9-19-2003 Submission

ML033440288
Person / Time
Site:	Cooper
Issue date:	10/06/2003
From:	Bhalchandra Vaidya NRC/NRR/DLPM/LPD4
To:	Nebraska Public Power District (NPPD)
vaidya B, NRR/DLPM, 415-3308
References
TAC MB6821
Download: ML033440288 (4)

Text

i CATEMP\GW)00001.TMP Page 1ii 1 Pane I C:\TEMP\GW]OOOO1 .TMP Mail Envelope Properties (3F815B60.12D: 21: 21146)

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MB6821, RP-06, Rev.1, Draft RAIs on 9-19-2003 submission Creation Date: 10/6/03 8:09AM From: Bhalchandra Vaidya Created By: BKV@nrc.gov Recipients Action Date & Time nppd.com Transferred 10/06/03 08:09AM reroger (Reroger@nppd.com) nrc.gov owf4_po.OWFNDO Delivered 10/06/03 08:09AM MCH3 CC (Michelle Honcharik) Opened 10/06/03 08: 12AM Post Office Delivered Route nppd.com owf4_po.OWFNDO 10/06/03 08:09AM nrc.gov Files Size Date & Time MB6821-Cooper-Draft RAIs on 91903 submission-cooperdraft ira.wpd 6792 10/06/03 07:37AM MESSAGE 1928 10/06/03 08:09AM Options Auto Delete: No Expiration Date: None Notify Recipients: Yes Priority: Standard Reply Requested: No Return Notification: None Concealed

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No Security: Standard To Be Delivered: Immediate Status Tracking: Delivered & Opened

I-I Bhalchandra Vaidya - MB6821, RP-06, Rev.1, Draft RAls on 9-19-2003 submission Page ii From: Bhalchandra Vaidya To: Reroger~nppd.com Date: 10/6/03 8:09AM

Subject:

MB6821, RP-06, Rev.1, Draft RAls on 9-19-2003 submission Attached are the Draft RAls I just received from the John Huang. They have been okayed by his Section Chief.

Can we still talk tommorrow, AM or PM?, PM, Michelle Honcharik is not in on Wed. and she has requested that she would like to be in on the call.

Please let me know time, phone no. for me to call , and the list of your attendees ASAP. I would be inviting Bob Gramm (My Section Chief), Michelle (PM for Cooper), John Huang (Staff Reviewer), and His Section Chief, Dave Tarao. I do not know exactly will be present depending on their availability.

I do not think we can wait for everybody to be available as long as key people are present to get rsponsefinformation/explainations to John Huang. John is going on Vacation fro 10-14 to 10-30 and I am going on vacation from 10-30 to 12-1. John and myself will be there this week for the call.

Thanks.

Bhalchandra Vaidya NRRIDLPM Licensing Project Manager, PDIV-1 Grand Gulf Nuclear Station, Unit 1 301-415-3308 M/S: 0-7D1 CC: Honcharik, Michelle

I Bhalchandra Vaidya - MB6821-Cooper-Draft RAls on 91903 submission-cooperdraft ira.wpd Paae 1 11I I Bhalchandra Vaidya MB6821-Cooper-Draft RAts on 91903 submission-cooperdraft ira.wpd Paae Request for Additional Information (RAI)

Relief Request RP-06 Cooper Nuclear Station (TAC No. MB6821)

RAI #1 The licensee and its pump experts have concluded that since initial installation of the core spray pump, the pump tests using the full-flow capabilities of the test line have not caused any damage to the pump, and the pump is operable. The staff finds that although no significant damage may have occurred based on the cumulative pump operating time during the quarterly tests (approximately 40 to 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />), the core spray pump is required to perform a safety function for an extended period of time following a LOCA. Therefore, the data collected from the pump tests are not sufficient to justify the long-term operability of the pump.

With regard to the long term operability of the pump, the licensee states that the pump vendor (Byron-Jackson), in a letter dated February 16, 1973, indicated that such low acceleration levels, along with the system acting as a rigid structure (between motor and pump), means that the motor and pump can operate with these levels of vibration with absolutely no impairment of operating life." (Ref. page 7 of Attachment 2).

The above statement, however, did not provide an adequate basis for its conclusion. In order to justify the long-term operability of the affected pump, the conclusion should be substantiated by analyses, operating history of similar pumps, or other technical bases appropriate to the pump. The staff requests that further justification or relevant documents demonstrating the pump's long-term operability at these low-frequency vibration levels be submitted for staff review.

The licensee further argues that its alternative is similar or more conservative than that provided by the Sequoyah Nuclear Plant (SNP) in its alternative that was authorized by the staff. In the case of SNP, the licensee requested relief from the vibration that occurred only during the quarterly pump test using a mini-flow test line. During refueling outages, the pump test at SNP uses the normal post-LOCA flow path (full-flow line) and did not experience vibration problems.

Consequently, SNP did not have to address the issue related to long-term operability of the affected pumps. SNP was requested only to justify that the mini-flow test had not caused damage or degradation to the pump, which in turn could be verified every two years by a full-flow test.

RAI #2 In lieu of meeting the Code requirements, the licensee proposes to filter out the low frequency vibration data at points 1H and 5H, and monitor them administratively for any anomaly or trend of high vibration. However, before the staff can evaluate the acceptability of monitoring low-frequency vibration administratively, (i.e., not in conjunction with ASME Code inservice testing requirements), the licensee is requested to demonstrate (1) that the excluded low-frequency vibration has no significant impact on the pump's long-term operability (see RAI

1. 1) and (2) the excluded vibration can be verified to stay within acceptable limits. To ensure that the vibration remains within acceptable levels, the proposed alternative should be revised to include an acceptable vibration limit for points 1H and 5H and required actions to be taken if the these limits are exceeded. Any proposed alternative must be part of the IST program, and

I Bhalchandra Vaidya - MB6821-Cooper-Draft RAls on 91903 submission-cooperdraft ira.wpd Page 21 administrative monitoring of the affected vibration parameters without specific acceptance criteria and corrective action will not be accepted.

RAI #3 The licensee states (Ref. page 5 of Attachment 2) that the forcing function in this case is caused by flow turbulence attributed in large part to the S-curve in the piping just off the pump discharge. The licensee is requested to address what actions have been taken to modify this portion of the piping in order to reduce vibration, especially when it became clear to the licensee that the primary source of high vibration was the flow turbulence in and around these areas.