ML083300210

Request for Additional Information Related to License Amendment Request for Technical Specifications Changes to Allow Use of Westinghouse 0.422-Inch OD 14X14 Vantage + Fuel (TAC Nos. MD9142/9143)

ML083300210
Person / Time
Site:	Prairie Island
Issue date:	12/15/2008
From:	Thomas Wengert Plant Licensing Branch III
To:	Wadley M Northern States Power Co
Wengert, Thomas
References
TAC MD9142, TAC MD9143
Download: ML083300210 (4)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 December 15, 2008 Mr. Michael D. Wadley Site Vice President Prairie Island Nuclear Generating Plant Northern States Power Company - Minnesota 1717 Wakonade Drive East Welch, MN 55089

SUBJECT:

PRAIRIE ISLAND NUCLEAR GENERATING PLANT, UNITS 1 AND 2 REQUEST FOR ADDITIONAL INFORMATION RELATED TO LICENSE AMENDMENT REQUEST FOR TECHNICAL SPECIFICATIONS CHANGES TO ALLOW USE OF WESTINGHOUSE 0.422-INCH OD 14X14 VANTAGE+ FUEL (TAC NOS. MD9142 AND MD9143)

Dear Mr. Wadley:

By letter to the U.S. Nuclear Regulatory Commission (NRC) dated June 26, 2008, as supplemented by letters dated August 4, August 26, and November 14, 2008, Nuclear Management Company, LLC, a predecessor license holder to the Northern States Power Company, a Minnesota corporation, submitted a request for Technical Specification changes to allow the use of Westinghouse 0.422-inch outside diameter 14X14 VANTAGE+ fuel for Prairie Island Nuclear Generating Plant, Units 1 and 2.

The NRC staff is reviewing your submittal and has determined that additional information is required to complete the review. The specific information requested is addressed in the enclosure to this letter. During a discussion with your staff on November 13, 2008, it was agreed that you would provide a response by January 30, 2009.

The NRC staff considers that timely responses to requests for additional information help ensure sufficient time is available for staff review and contribute toward the NRC's goal of efficient and effective use of staff resources. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-4037.

Sincerely, Thomas J. Wengert, Senior Project Manager Plant Licensing Branch 111-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-282 and 50-306

Enclosure:

Request for Additional Information cc w/encl: Distribution via ListServ

REQUEST FOR ADDITIONAL INFORMATION PRAIRIE ISLAND NUCLEAR GENERATING PLANT, UNITS 1 AND 2 DOCKET NOS. 50-282 AND 50-306 In reviewing the Nuclear Management Company, LLC*, submittal dated June 26, 2008 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML081821037), as supplemented by letters dated August 4 (ADAMS Accession No. ML082210260), August 26 (ADAMS Accession No. ML082400518), and November 14,2008 (ADAMS Accession No. ML083190820), which requested technical specification (TS) changes related to a change in fuel type from Westinghouse OAOO-inch outside diameter (00) Vantage+

(400V+) fuel to Westinghouse OA22-inch 00 Vantage+ (422V+) fuel for Prairie Island Nuclear Generating Plant, Units 1 and 2 (PINGP), the U.S. Nuclear Regulatory Commission (NRC) staff has determined that the following information is needed in order to complete its review:

The license amendment request included a revisitation of the accident and transient analyses, some of which were re-analyzed, and the loss-of-coolant accident (LOCA) analyses, which were affected by the requested fuel transition.

1. The TS changes requested to support the fuel upgrade include a change to TS 2.1.1.2, Reactor Core Safety Limits. The peak fuel centerline temperature for non-gadolinia bearing fuel is requested to increase. Three points of justification are provided; two are repeated in this request:

(i). The fuel centerline temperature melting limits are referenced in WCAP 8720, Addendum 3. These melting limits are integrated into the peak fuel centerline temperature evaluation methodology used to confirm that the fuel centerline melt design criteria are met.

(ii). The request is justified based on WCAP-12488-A, "Westinghouse Fuel Criteria Evaluation Process," October 1994.

a. For Item (i), confirm that the fuel centerline temperature melting limits correspond acceptably to the requested TS change, that is, that the TS limit matches or is conservative with respect to the referenced fuel centerline temperature melting limit.

b. Also for Item (i), confirm that the referenced centerline temperature melting limits are specifically applicable to all fuel designs planned for incorporation in the 422V+ transition cycles.

c. Regarding Item (ii), is there a specific Fuel Criteria Evaluation Process (FCEP) notification letter referencing this change to fuel centerline melting temperature?

• On September 22, 2008, Nuclear Management Company, LLC (NMC), transferred its operating authority to Northern States Power Company, a Minnesota Corporation (NSPM). By letter dated September 3, 2008, NSPM stated that it would assume responsibility for actions and commitments submitted by NMC.

ENCLOSURE

-2 What specific aspect of the FCEP provides justification for the requested TS change?

Please explain.

2. In a post-LOCA scenario, when analyzing boric acid precipitation, it is generally accepted as conservative to assume that no boric acid carries over into the coolant loops from the core. Please consider the opposite of this - that boric acid could carry, through entrained liquid or due to volatility in water vapor, into the reactor coolant loops - and discuss whether it would be possible to precipitate boric acid in steam generator tubes and cause excessive tube plugging. Available analyses do not appear to account for this possibility.

How susceptible is PINGP to such a scenario?

3. The NRC staff reviewed documents during an October 1-2, 2008, audit at the Westinghouse Energy Center in support of the NRC staff's review of the requested fuel upgrade. During its audit, the NRC staff identified potentially non-conservative assumptions made regarding the PINGP capability for post-LOCA, long-term core cooling. Please re-evaluate the post-LOCA, long-term core cooling at PINGP, and demonstrate acceptable safety injection capability. The re-evaluation should at feast consider the following:

a. The acceptance criteria set forth in 10 CFR 50.46(b).

b. The 10 CFR Part 50, Appendix K, decay heat requirements.

c. Differences in lattice pitch over generically studied plants referenced in the analysis (Westinghouse Proprietary Calculation CN-LiS-O?-126, "Prairie Island Units 1 and 2 (NSP/NRP) Post-LOCA Long-Term Cooling Analysis in Support of the 422V+ Fuel Transition Program").

d. Differences in post-LOCA decay power shape compared to the power shape evaluated in CN-LlS-0?-126 (Westinghouse Proprietary) and the effect that this difference could have on core boiloff.

Mr. Michael D. Wadley December 15, 2008 Site Vice President Prairie Island Nuclear Generating Plant Northern States Power Company - Minnesota 1717 Wakonade Drive East Welch, MN 55089

SUBJECT:

PRAIRIE ISLAND NUCLEAR GENERATING PLANT, UNITS 1 AND 2 REQUEST FOR ADDITIONAL INFORMATION RELATED TO LICENSE AMENDMENT REQUEST FOR TECHNICAL SPECIFICATIONS CHANGES TO ALLOW USE OF WESTINGHOUSE 0.422-INCH OD 14X14 VANTAGE+ FUEL (TAC NOS. MD9142 AND MD9143)

Dear Mr. Wadley:

By letter to the U.S. Nuclear Regulatory Commission (NRC) dated June 26, 2008, as supplemented by letters dated August 4, August 26, and November 14, 2008, Nuclear Management Company, LLC, a predecessor license holder to the Northern States Power Company, a Minnesota corporation, submitted a request for Technical Specification changes to allow the use of Westinghouse 0.422-inch outside diameter 14X14 VANTAGE+ fuel for Prairie Island Nuclear Generating Plant, Units 1 and 2.

The NRC staff is reviewing your submittal and has determined that additional information is required to complete the review. The specific information requested is addressed in the enclosure to this letter. During a discussion with your staff on November 13, 2008, it was agreed that you would provide a response by January 30, 2009.

The NRC staff considers that timely responses to requests for additional information help ensure sufficient time is available for staff review and contribute toward the NRC's goal of efficient and effective use of staff resources. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-4037.

Sincerely, IRAJ Thomas J. Wengert, Senior Project Manager Plant Licensing Branch 111-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-282 and 50-306

Enclosure:

Request for Additional Information cc w/encl: Distribution via ListServ DISTRIBUTION:

PUBLIC LPL3-1 RIF RidsNrrDorlLpl3-1 Resource RidsNRRPMTWengert Resource RidsNrrLATHarris Resource RidsNrrDssSrxb Resource RidsAcrsAcnw_MailCTR Resource RidsOgcRp Resource B. Parks, NRR RidsRgn3MailCenter Resource RidsNrrDorlDpr Resource ADAMS Accession Number' ML083300210 OFFICE LPL3-1/PM LPL3-1/LA NRRIDSS/SRXB/BC LPL3-1/BC NAME TWengert THarris GCranston* LJames DATE 12/08/08 12/05/08 10/24/08 12/15/08

• via memo dated 10/24/2008 OFFICIAL RECORD COpy