ET 14-0003, Operating Corporation - Response to Request for Additional Information Regarding License Amendment Request for the Transition to Westinghouse Core Design and Safety Analysis

Operating Corporation - Response to Request for Additional Information Regarding License Amendment Request for the Transition to Westinghouse Core Design and Safety Analysis

ML14035A224
Person / Time
Site:	Wolf Creek
Issue date:	01/28/2014
From:	Broschak J Wolf Creek
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
ET 14-0003
Download: ML14035A224 (5)

Text

WLFCREEK NUCLEAR OPERATING CORPORATION John P. Broschak Vice President Engineering January 28, 2014 ET 14-0003 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555

Reference:

1)

Letter ET 13-0023, dated August 13, 2013, from J. P. Broschak, WCNOC, to USNRC

2)

Letter dated December 13, 2013, from C. F. Lyon, USNRC, to M. W.

Sunseri, WCNOC, "Wolf Creek Generating Station - Request for Additional Information Re: Transition to Westinghouse Core Design and Safety Analysis (TAC NO. MF2574)"

Subject:

Docket No. 50-482:

Response to Request for Additional Information Regarding License Amendment Request for the Transition to Westinghouse Core Design and Safety Analysis Gentlemen:

Reference 1 provided the Wolf Creek Nuclear Operating Corporation (WCNOC) application to revise the Technical Specifications to support transition to the Westinghouse core design and safety analysis methodologies.

The amendment request included revising the Wolf Creek Generating Station (WCGS) licensing basis by adopting the Alternative Source Term radiological analysis methodology in accordance with 10 CFR 50.67, "Accident source term."

Reference 2 provided a Nuclear Regulatory Commission (NRC) request for additional information related to the application. The questions in Reference 2 were provided by electronic mail on December 11, 2013. By subsequent electronic mail on December 23, 2013, the original ESGB-RAI-1 and ESGB-RAI-2 were replaced with a single request. The Attachment provides WCNOC's response to the request for additional information and reflects the December 23, 2013 agreed upon requested information.

The additional information does not expand the scope of the application and does not impact the no significant hazards consideration determination presented in Reference 1.

In accordance with 10 CFR 50.91, "Notice for public comment; State consultation," a copy of this submittal is being provided to the designated Kansas State official.

P.O. Box 411 / Burlington, KS 66839 / Phone: (620) 364-8831 An Equal Opportunity Employer M/F/HC/VET

ET 14-0003 Page 2 of 3 This letter contains no commitments. If you have any questions concerning this matter, please contact me at (620) 364-4085, or Mr. Michael J. Westman at (620) 364-4009.

Sincerely 6 o P. Broschak JPB/rlt Attachment cc:

T. A. Conley (KDHE), w/a M. L. Dapas (NRC), w/a C. F. Lyon (NRC), w/a N. F. O'Keefe (NRC), w/a Senior Resident Inspector (NRC), w/a

ET 14-0003 Page 3 of 3 STATE OF KANSAS COUNTY OF COFFEY

)

)

John P. Broschak, of lawful age, being first duly sworn upon oath says that he is Vice President Engineering of Wolf Creek Nuclear Operating Corporation; that he has read the foregoing document and knows the contents thereof; that he has executed the same for and on behalf of said Corporation with full power and authority to do so; and that the facts therein stated are true and correct to the best of his knowledge, information and belief.

By y

.7 JoJ41P. Broschak V (-e President Engineering SUBSCRIBED and sworn to before A GAYLESHEPHEARD Ch Notary Pubfii9.

Stata of Kansas My Appt. Expires lA+d me this 2L8 day of I rLuLL*CQ

,2014.

Notary Expiration Date

Attachment to ET 14-0003 Page 1 of 2 Response to Request for Additional Information Reference 1 provided Wolf Creek Nuclear Operating Corporation's (WCNOC) application to revise the Technical Specifications to support transition to the Westinghouse core design and safety analysis methodologies.

The amendment request included revising the Wolf Creek Generating Station (WCGS) licensing basis by adopting the Alternative Source Term radiological analysis methodology in accordance with 10 CFR 50.67, "Accident source term."

Reference 2 provided a Nuclear Regulatory Commission (NRC) request for additional information related to the application. The questions in Reference 2 were provided by electronic mail on December 11, 2013. By subsequent electronic mail on December 23, 2013 (Reference 3), the original ESGB-RAI-1 and ESGB-RAI-2 were replaced with a single request. The specific NRC question is provided in italics.

1.

EMCB-RAI-1 Implementation of an Alternate Source Term (AST) in accordance with Section 50.67, "Accident source term," of Title 10 of the Code of Federal Regulations (10 CFR) could affect structures, systems, and components (SSCs) which were not previously evaluated for the consequences of a design-basis accident (DBA) and, as such, may not be seismically qualified. Appendix A to 10 CFR Part 100, "Reactor Site Criteria," requires that SSCs necessary to assure the capability of the plant to mitigate the consequences of accidents, which could result in exposures comparable to the guideline exposures provided in 10 CFR Part 100, be designed to remain functional during and after a safe shutdown earthquake. In accordance with the 10 CFR Part 100 requirements, please identify SSCs which may be affected by the implementation of the proposed AST and address the following:

a)

Indicate whether any non-safety-related SSCs are being credited in the proposed AST license amendment.

b)

For any nonsafety-related SSCs credited in the AST, confirm that the SSCs have been seismically qualified in accordance with the plant licensing basis.

c)

Indicate whether the SSCs are new or existing.

d)

Describe the location of the SSCs and the seismic qualification method employed to demonstrate the seismic ruggedness of these SSCs, such as the plant licensing basis or an NRC-endorsed industry standard.

e)

Summarize the results of the seismic qualification of the equipment, indicating whether any modifications or re-design will be necessary in support of the AST.

Response

The proposed license amendment request included the adoption of Alternative Source Term (AST) radiological analysis methodology consistent with 10 CFR 50.67, "Accident source term." The design basis radiological consequence analyses performed for AST did not credit any non-safety related structures, systems, and components (SSCs). This is consistent with the current licensing basis analysis of record that does not credit any non-safety related SSCs. Additionally, the design basis radiological consequence analyses performed for AST does not result in modifications to existing SSCs or does not require the installation of any new SSCs and therefore no additional seismic qualification was performed.

Attachment to ET 14-0003 Page 2 of 2

2.

ESGB-RAI-1 Describe the analysis methodology used to determine the pH in the sump water during the period of 30 days post-LOCA. Include detailed calculations of time dependent pH values in the sump during a 30 day period post-LOCA to demonstrate that the pH remains basic throughout this time period.

Response: As discussed in Section 4.4.2 of Enclosure VI to Reference 1, the containment sump pH calculation did not include consideration of acid generation (nitric acid produced by the irradiation of water and air or hydrochloric acid produced by the radiolysis of chlorine bearing materials) as they were considered secondary effects.

In Section 4.4.2 of Enclosure VI to Reference 1, WCNOC indicated that it was expected that the effect of acid generation on sump pH would decrease the pH value less than 0.1 pH based on a comparison of Byron Station information and the conclusion reached by the NRC in the safety evaluation for Amendment No.

147 for the Byron Station and Amendment No. 140 for the Braidwood Station (Reference 4).

WCNOC is performing a plant-specific sump pH calculation to determine the effect of the post-LOCA acidic sources. Details and results from this calculation will be provided in a supplement to this request for additional information by March 27, 2014.

References:

1.

WCNOC Letter ET 13-0023, "License Amendment Request for the Transition to Westinghouse Core Design and Safety Analysis," August 13, 2013. ADAMS package Accession No. ML13247A075.

2.

Letter from C. F. Lyon, USNRC, to M. W. Sunseri, WCNOC, "Wolf Creek Generating Station - Request for Additional Information Re: Transition to Westinghouse Core Design and Safety Analysis (TAC NO. MF2574)," December 13, 2013. ADAMS Accession No. ML13345B335.

3.

Electronic mail from C. F. Lyon, USNRC, to S. G. Wideman, WCNOC, "RE: Wolf Creek Generating Station - Request for Additional Information Re: Transition to Westinghouse Core Design and Safety Analysis (TAC NO. MF2574)," December 23, 2013. ADAMS Accession No. ML13357A252.

4.

Letter from R. F. Kuntz, USNRC, to C. M. Crane, Exelon Generation Company, "Byron Station, Unit Nos. 1 and 2, and Braidwood Station, Unit Nos. 1 and 2 -

Issuance of Amendment Re: Alternative Source Term (TAC NOS. MC6221, MC6222, MC6223, and MC6224)," September 8, 2006. ADAMS Accession No. ML062340420.