ML050250435
| ML050250435 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 01/19/2005 |
| From: | Mahesh Chawla NRC/NRR/DLPM/LPD3 |
| To: | Vincent D - No Known Affiliation |
| Chawla M, NRR/.DLPM, 415-8371 | |
| References | |
| TAC MC3043, TAC MC3044 | |
| Download: ML050250435 (3) | |
Text
From:
Mahesh Chawla To:
Dale Vincent Date:
1/19/05 1:27PM
Subject:
Prairie Island - LAR - MC3043/MC3044 - Unresolved Items related to Methods of Evaluation of CL For the above referenced LAR, request for additional informaiton was sent to you via e-mail on 12/8/04. A follow-up telephone conference was held between Prairie Island representatives and the NRC staff, during which this amendment request was discussed in more detail. As a result of this discussion, it was decided that the licensee will provide response to the following NRC staff questions. Please provide your response to the following by February 11, 2005.
Request for Additional Information
- 1) You indicated that the evaluation applies acceptance criteria from American Society of Mechanical Engineers (ASME)Section III, Subsection ND, Service Level D when performing stress analyses of the cooling water (CL) system non-Class I piping with design basis seismic loads. The proposed methodology and acceptance criteria provide a conservative approach for demonstrating that the CL system will perform its safety function following a design basis seismic event. Provide a description of analysis including the methodology, loss of coolant accident (LOCA) loads for the faulted condition, load combinations, input response spectra to the seismic analysis, modeling and computer code used, assumptions and resulting stresses in comparison against the code allowable limits.
- 2) Though NRC is reviewing the criteria for analyzing cooling water system non-seismic piping, confirm that the piping will continue to be protected from the failure of non-seismic structures, systems and components (SSCs) in accordance with the existing plant licensing basis. Please explain any exceptions.
- 3) The licensee proposes to credit automatic isolation valves for excluding cooling water system non-seismic piping from consideration. Confirm that these valves are seismic Category I, safety-related valves, which will automatically actuate to close during a seismic event, and that the single-failure criterion will be satisfied.
- 4) Explain in detail specific operator actions that are being relied upon for postulated pipe break conditions for NRC assessment of human factors considerations.
CC:
Cheng-Ih Wu; David Muller; James Tatum; Ron Young Mail Envelope Properties (41EEA679.E4D : 15 : 21352)
Subject:
Prairie Island - LAR - MC3043/MC3044 - Unresolved Items related to Methods of Evaluation of CL Creation Date:
1/19/05 1:27PM From:
Mahesh Chawla Created By:
MLC@nrc.gov Recipients Action Date & Time TWGWPO01.HQGWDO01 Delivered 01/19/05 01:27PM DSM3 CC (David Muller) owf2_po.OWFN_DO Delivered 01/19/05 01:27PM CIW1 CC (Cheng-Ih Wu)
Opened 01/19/05 02:17PM JET1 CC (James Tatum)
Opened 01/19/05 01:44PM
RMY CC (Ron Young) nmcco.com Transferred 01/19/05 01:27PM dale.vincent (Dale Vincent)
Post Office Delivered Route TWGWPO01.HQGWDO01 01/19/05 01:27PM owf2_po.OWFN_DO 01/19/05 01:27PM nmcco.com Files Size Date & Time MESSAGE 3039 01/19/05 01:27PM Options Auto Delete:
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Delivered & Opened ADAMS Accession No.: ML050250435