NOC-AE-14003157, CFR50.46 Thirty-Day Report of Significant ECCS Model Changes

CFR50.46 Thirty-Day Report of Significant ECCS Model Changes

ML14205A014
Person / Time
Site:	South Texas
Issue date:	07/07/2014
From:	Dunn R South Texas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
G25, NOC-AE-14003157, STI: 33897028
Download: ML14205A014 (2)

Text

Nuclear Operating Company South Texas Pro/ect Electric Generating Station PO.Box 289 Wadsworth, Texas 77483 -

July 7, 2014 NOC-AE-14003157 File No.: G25 10CFR50.46 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001 South Texas Project Unit 1 Docket No. STN 50-498 10CFR50.46 Thirty-Day Report of Siqnificant ECCS Model Chanqes

Reference:

Letter from R.F. Dunn to NRC Document Control Desk, "10CFR 50.46 ECCS Evaluation Model Significant Change/Error Report," dated October 17, 2012, NOC-AE-12002912 (ML12310A383)

In accordance with the requirements of 10 CFR 50.46(a)(3)(ii),STP Nuclear Operating Company (STPNOC) is submitting a 30 day report for a significant change in the South Texas Unit 1 Emergency Core Cooling Model.

The value for the hot assembly average rod Gamma Energy Deposition Model for Unit 1 Cycle 19, increased 0.0041 above the analyzed value of 0.984. This resulted in an estimated increase in Peak Clad Temperature (PCT) of 3°F to the value of 2117°F reported in the Reference letter.

The new PCT value for Unit 1 Cycle 19 is 2120°F. Since the absolute value of PCT changes to the Analysis of Record exceeds 50'F, the change is considered significant in accordance with 10CFR50.46(a)(3)(i).

No schedule for reanalysis is proposed since the Unit 1 Cycle 19 PCT remains below the 10CFR50.46(b)(1) limit of 2200°F.

There are no commitments in this letter.

If there are any questions please contact Charlie Albury at (361) 972-8901.

Roland F. Dunn Manager Nuclear Fuel and Analysis cra STI: 33897028

NOC-AE-14003157 Page 2 of 2 cc:

(paper copy) (electronic copy)

Regional Administrator, Region IV A. H. Gutterman, Esquire U. S. Nuclear Regulatory Commission Morgan, Lewis & Bockius LLP 1600 East Lamar Boulevard Arlington, TX 76011-4511 Balwant K. Singal U. S. Nuclear Regulatory Commission Balwant K. Singal John Ragan Senior Project Manager Chris O'Hara U.S. Nuclear Regulatory Commission Jim von Suskil One White Flint North (MS 8 B1) NRG South Texas LP 11555 Rockville Pike Rockville, MD 20852 Kevin Polio NRC Resident Inspector Cris Eugster U. S. Nuclear Regulatory Commission L. D. Blaylock P. 0. Box 289, Mail Code: MNl 16 CPS Energy Wadsworth, TX 77483 Peter Nemeth Crain Caton & James, P.C.

C. Mele John Wester City of Austin Richard A. Ratliff Texas Department of State Health Services Robert Free Texas Department of State Health Services