NL-15-0680, Annual Report for 2014 and Significant Change/Error Report

Annual Report for 2014 and Significant Change/Error Report

ML15098A514
Person / Time
Site:	Hatch
Issue date:	04/08/2015
From:	Pierce C Southern Co, Southern Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NL-15-0680
Download: ML15098A514 (6)

Text

Charles R. Pierce Southern Nuclear Regulatory Affairs Director Operating Company, Inc.

40 Inverness Center Parkway Post Office Box 1295 Birmingham, AL 35201 Tel 205.992.7872 Fax 205.992.7601 SOUTHERN A COMPANY April 8, 2015 Docket Nos.: 50-321 NL-15-0680 50-366 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Edwin I. Hatch Nuclear Plant Units 1 and 2 10 CFR 50.46 ECCS Evaluation Model Annual Report for 2014 and Significant Change I Error Report Ladies and Gentlemen:

In accordance with the requirements of 10 CFR 50.46(a)(3)(ii), Southern Nuclear Operating Company (SNC) is submitting the enclosed Edwin I. Hatch Nuclear Plant (HNP) Units 1 & 2 emergency core cooling system (ECCS) evaluation model annual report for 2014. In addition, as a result of the use of GNF2 fuel for the HNP Unit 2 Cycle 24 core load, SNC is submitting a HNP Unit 2 significant change/error report.

HN P Unit 2 Cycle 24 is the first HNP cycle with a reload of GNF2 fuel. Cycle 24 went critical on March 10, 2015. The new fuel introduction required re-analysis of ECCS-LOCA performance evaluation of the limiting large break LOCA and small break LOCA. The re-analysis resulted in an increase in the calculated peak cladding temperature (PCT) increase of 180°F for the GNF2 fuel as compared to the previous fuel design (GE14). The analysis also incorporated a methodology change to SAFER/PRIME-LOCA from the previous SAFER/GESTR-LOCA. The analysis meets the NRC Safety Evaluation Report (SER) requirements on the SAFER/ PRIME-LOCA application, and demonstrates that the 10 CFR 50.46 PCT and maximum cladding oxidation acceptance criteria are satisfied.

There were no changes or errors to the GE14 ECCS-LOCA evaluation model for 2014 other than those reported in SNC letter dated June 20, 2014 (ML14171A627).

The GNF2 ECCS-LOCA evaluation incorporates all previous code error notices and provides a new baseline for HNP Unit 2 with GNF2 fuel. This re-analysis was performed for both units and will serve as a baseline for Unit 1 next spring after its first reload of GNF2 fuel is installed. However, until then, Unit 1 continues to be licensed using the existing GE14 ECCS-LOCA evaluation.

U. S. Nuclear Regulatory Commission NL-15-0680 Page 2 This letter contains no NRC commitments. If you have any questions, please contact Ken McElroy at (205) 992-7369.

Respectfully submitted, C.71-C. R. Pierce Regulatory Affairs Director CRP/RMJ

Enclosure:

Hatch Nuclear Plant 10 CFR 50.46 ECCS Evaluation Model Annual Report for 2014 & Significant Change/Error Report cc: Southern Nuclear Operating Company Mr. S. E. Kuczynski, Chairman, President & CEO Mr. D. G. Bost, Executive Vice President & Chief Nuclear Officer Mr. D. R. Vineyard, Vice President- Hatch Mr. M. D. Meier, Vice President- Regulatory Affairs Mr. D. R. Madison, Vice President- Fleet Operations Mr. 8. J. Adams, Vice President- Engineering Mr. G. L. Johnson, Regulatory Affairs Manager - Hatch RTYPE: C HA02.004 U.S. Nuclear Regulatory Commission Mr. V. M. McCree, Regional Administrator Mr. R. E. Martin, NRR Senior Project Manager - Hatch Mr. D. H. Hardage, Senior Resident Inspector- Hatch

Edwin I. Hatch Nuclear Plant 10 CFR 50.46 ECCS Evaluation Model Annual Report for 2014 and Significant Change/Error Report Enclosure Hatch Nuclear Plant 10 CFR 50.46 ECCS Evaluation Model Annual Report for 2014 & Significant Change/Error Report

Enclosure to NL-15-0680 Hatch Nuclear Plant 10 CFR 50.46 ECCS Evaluation Model Annual Report for 20 14 & Significant Change/Error Report Edwin I. Hatch Nuclear Plant Unit 1 SAFERIGESTR-LOCA Analysis Model Table 1-1a- SAFERIGESTR-LOCA Summary of Changes I Errors (2014)

Estimated Description Effect

( P CT)

None affecting PCT1 N/A Table 1-1b- Cumulative Impact of Changes I Errors GE14 Description IPCTI (oF)

• Changes/Errors Previously Reported (Reference 1) 01

• Summary of Changes/Errors (2014) 01 Cumulative Total 0 1 On June 20, 2014, a Significant Change I Error report was submitted (Reference 1). This "reset the baseline PCT for reporting purposes. There were no additional changes I errors in 20 14 other than those reported in Reference 1.

E 1- 1

Enclosure to NL-15-0680 Hatch Nuclear Plant 10 CFR 50.46 ECCS Evaluation Model Annual Report for 2014 & Significant Change/Error Report Edwin I. Hatch Nuclear Plant Unit 2 Table 1-2a- SAFER/GESTR-LOCA Summary of Changes I Errors (2014) (GE14)

Estimated Description Effect

( PCT)

None affecting PCT1 N/A Table 1-2b- SAFER/PRIME-LOCA Summary of Changes I Errors (2014) (GNF2)

Estimated Description Effect

( PCT)

N/A (Not used in 2014) N/A Table 1-2c- Current Changes I Errors GE14 GNF2 Estimated Estimated Description Effect Effect

( PCT) ( PCT)

None affecting PCT2 0 03 Table 1-2d- Cumulative Impact of Changes /Errors GE14 GNF2 Description IPCTI IPCTI (oF) (oF)

• Changes/Errors Previously Reported (Reference 1) 01 N/A

• Current Changes I Errors 0 03

• Summary of Changes/Errors (2014) 01 N/A Cumulative Total 0 0 E1-2

Enclosure to NL- 15-0680 Hatch Nuclear Plant 1 0 CFR 50.46 ECCS Evaluation Model Annual Report for 20 14 & Significant Change/Error Report 1 On June 20, 20 14, a Significant Change I Error report was submitted (Reference 1) This "reset" the baseline PCT for reporting purposes. There were no additional changes I errors in 2014 other than those reported in Reference 1.

2 The GNF2 fuel has a licensing basis PCT that is 250°F greater than the GE14 licensing basis PCT, or 180°F greater than the GE 14 error-corrected PCT. All previous code error notices have been included in the new GNF2 licensing basis PCT, while code error notices from 20 1 1 -20 14 are not included in the GE14 licensing basis PCT. This explains why the difference in licensing basis PCT between GE 14 and GNF2 is 70°F greater than the error-corrected PCT difference.

3 There have been no changes to the GNF2 "baseline" PCT.

Reference:

1. Letter from C. R. Pierce to USNRC (NL- 14-0900), "Edwin I. Hatch Nuclear Plant Units 1 and 2 10 CFR 50.46 ECCS Evaluation Model Annual Report for 2013 and Significant Change/Error Report," dated June 20, 2014 E 1-3