RS-15-086, Partial Withdrawal of Request for Exemption from 10 CFR 50, Appendix a, GDC-56 - Penetration Z-48 (Drywell)

Partial Withdrawal of Request for Exemption from 10 CFR 50, Appendix a, GDC-56 - Penetration Z-48 (Drywell)

ML15093A226
Person / Time
Site:	Nine Mile Point
Issue date:	03/30/2015
From:	Korsnick M Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RS-15-086
Download: ML15093A226 (2)

Text

Adno

• Maria Korsnick Exel on Generationl

" Senior Vice President, Northeast Operations Chief Nuclear Officer. CENG 100 Constellation Way ii,-'Suite 500P Constellation Energy Nuclear Group, LLC Suime5OOP Baltimore, MD 21202 410-470-5133 Office 443-213-6739 Fax www.exeloncorp.com maria.korsnick@exeloncorp.com RS-15-086 March 30, 2015 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike Rockville, MD 20852 Nine Mile Point Nuclear Station, Unit 2 Renewed Facility Operating License No. NPF-69 Docket No. 50-410

Subject:

Partial Withdrawal of Request for Exemption from 10 CFR 50, Appendix A, GDC Penetration Z-48 (Drywell)

References:

(1) NRC Order Number EA-13-109, Order Modifying Licenses with Regard to Reliable Hardened Containment Vents Capable of Operation Under Severe Accident Conditions, dated June 6, 2013 (ML13143A321)

(2) Letter from M. G. Korsnick (Exelon) to Document Control Desk (NRC),

Nine Mile Point Nuclear Station, Unit 2, Request for Exemption from 10 CFR 50, Appendix A, GDC-56, dated June 27, 2014 (ML14184B342)

On June 6, 2013, the Nuclear Regulatory Commission (NRC) issued Order EA-13-109 (Reference 1) to all licensees that operate boiling-water reactors (BWRs) with Mark I and Mark II containments to take certain actions to ensure the functionality of reliable hardened containment vent systems (HCVS) to remove decay heat and maintain control of containment pressure following events that result in loss of active containment heat removal capability or Extended Loss of AC Power (ELAP), and ensure that containment venting functions are also available during severe accident conditions.

In Reference (2), Exelon Generation Company, LLC (EGC) submitted a request for exemption from the requirements of 10 CFR 50, Appendix A, General Design Criterion (GDC) 56, Primary Containment Isolation, to permit an alternative containment isolation valve configuration for Nine Mile Point Unit 2 (NMP2) Penetrations Z-48 (Drywell) and Z-51 (Wetwell) in order to meet the requirements of Reference (1) regarding implementation of a HCVS.

On February 27, 2015, EGC and the NRC discussed the uncertainty regarding the need to modify the drywell vent. As a result, via this letter, EGC withdraws the portion of the exemption request submitted in Reference (2) regarding an alternative configuration for NMP2 Penetration Z-48 (Drywell). In the future, if EGC determines that a modification of the drywell penetration is required, a new exemption request will be submitted.

U. S. Nuclear Regulatory Commission March 30, 2015 Page 2 There are no regulatory commitments contained in this letter.

If there are any questions regarding this letter, please contact Mr. Terry Syrell, Regulatory Assurance Manager, at (315) 349-5245.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 3 0 th day of March 2015.

Respectfully, Mary G. orsnick MGK/STD cc: Regional Administrator, Region I, USNRC NRC Project Manager, NRR - Nine Mile Point Nuclear Station NRC Senior Resident Inspector - Nine Mile Point Nuclear Station