L-PI-09-035, Supplemental Information Regarding Application for Renewed Operating Licenses
| ML090690684 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 03/04/2009 |
| From: | Wadley M Northern States Power Co, Xcel Energy |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-PI-09-035 | |
| Download: ML090690684 (3) | |
Text
41 XcelEnergy-March 4, 2009 L-PI-09-035 10 CFR 54 U S Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Prairie Island Nuclear Generating Plant Units 1 and 2 Dockets 50-282 and 50-306 License Nos. DPR-42 and DPR-60 Supplemental Information Regarding Application for Renewed Operating Licenses By letter dated April 11, 2008, Northern States Power Company, a Minnesota Corporation, (NSPM) submitted an Application for Renewed Operating Licenses (LRA) for the Prairie Island Nuclear Generating Plant (PINGP) Units 1 and 2. In a letter dated January 23, 2009, NSPM responded to several NRC Requests for Additional Information (RAIs) regarding the Severe Accident Management Alternatives (SAMA) analyses in the Environmental Report included in the LRA. In a telephone conference on February 26, 2009, NSPM agreed to supplement certain of the RAI responses. of this letter provides the requested supplemental information.
If there are any questions or if additional information is needed, please contact Mr. Eugene Eckholt, License Renewal Project Manager.
Summary of Commitments This letter contains no new commitments or changes to existing commitments.
I declare under penalty of perjury that the foregoing is true and correct.
Executed on March 4, 2009.
Michael D. Wadley Site Vice President, Prairie Island Nuclear Generating Plant Units 1 and 2 Northern States Power Company - Minnesota 1717 Wakonade Drive East
- Welch, Minnesota 55089-9642 Telephone: 651.388.1121
Document Control Desk Page 2 Enclosure (1) cc:
Administrator, Region III, USNRC License Renewal Environmental Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN: Phil Mahowald Minnesota Department of Commerce Supplemental Information Regarding SAMA Analyses RAI 2b Supplemental Information In the January 23, 2009, response to RAI 2b, Tables 2b-3 and 2b-4 on page 13 showed that SAMA 3 became potentially cost-beneficial if a conditional probability of.25 were assumed for a temperature-induced steam generator tube rupture during core damage sequences involving high primary side and low secondary side steam generator pressures, and a dry steam generator secondary side. The response indicated that this NRC-requested assumption was not considered valid for PINGP, and that no further evaluation was planned for SAMA 3.
In the 2/26/03 telephone conference, NSPM agreed to reconsider this conclusion and evaluate SAMA 3 as potentially cost beneficial. Accordingly, NSPM has entered SAMA 3 into the Corrective Action Program for further evaluation.
RAI 5b Supplemental Information Environmental Report section F.5.1.5 on page F.5-5 provided a list of potential enhancements that had been developed during the IPE, and reexamined those enhancements in the context of the License Renewal SAMA analyses. Potential Enhancements 2 and 3 had been dispositioned as not cost beneficial based, in part, on a deterministic assessment of the consequences of pipe breaks that result in internal flooding. During the 1/26/09 telephone conference, NSPM agreed that this modeling limitation could have caused the value of Enhancements 2 and 3 to be understated.
Accordingly, NSPM has entered IPE Potential Enhancements 2 and 3 into the Corrective Action Program for further evaluation after the PRA has been updated with improved methodology for modeling pipe breaks.