ML19303A005

Revised Response to Application to Adopt 10 CFR 50.69, Risk-informed Categorization and Treatment of Structures, Systems, and Components for Nuclear Power Reactors

ML19303A005
Person / Time
Site:	Calvert Cliffs
Issue date:	10/30/2019
From:	David Gudger Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML19303A005 (2)

Text

200 Exelon Way Exelon Generation !)

Kennett Square. PA 19348 www.exeloncorp.com October 30, 2019 U.S. Nuclear Regulatory Commission A TIN: Document Control Desk Washington, DC 20555-0001 Calvert Cliffs Nuclear Power Plant, Units 1 and 2 Renewed Facility Operating License Nos. DPR-53 and DPR-69 Docket Nos. 50-317 and 50-318 10 CFR 50.90 10 CFR 50.69

Subject:

Revised Response to Application to Adopt 10 CFR 50.69, "Risk-informed categorization and treatment of structures, systems, and components for nuclear power reactors"

Reference:

1. Application to Adopt 10 CFR 50.69, "Risk-informed categorization and treatment of structures, systems, and components for nuclear power reactors," dated November 28, 2018.

By letter dated November 28, 2018 (Reference 1) Exelon Generation Company, LLC (Exelon) submitted its application to allow for the implementation of the provisions of Title 1 O of the Code of Federal Regulations (10 CFR), Part 50.69.

Exelon hereby revises the proposed wording for the License Condition as stated in Section 2.3 "Description of the Proposed Change" of Reference 1.

The new License Condition should read as follows:

"Exelon is approved to implement 10 CFR 50.69 using the processes For categorization of Risk-Informed Safety Class (RISC)-1, RISC-2, RISC-3, and RISC-4 Structures, Systems, and Components (SSCs) using: Probabilistic Risk Assessment (PRA) models to evaluate risk associated with internal events, including internal flooding, and internal fire; the shutdown safety assessment process to assess shutdown risk; the Arkansas Nuclear One, Unit 2 (AN0-2) passive categorization method to assess passive component risk for Class 2 and Class 3 and non-Class SSCs and their associated supports; the results of the non-PRA evaluations that are based on the IPEEE Screening Assessment for External Hazards updated using the external hazard screening significance process identified in ASME/ANS PRA Standard RA-Sa-2009 for other external hazards except seismic; and the alternative seismic approach as described in Exelon's original submittal letter dated November 28, 2018, and all its subsequent associated supplements as specified in License Amendment No. [XXX] elated [DATE]."

Revised Response to Application to Adopt 1 O CFR 50.69 October 30, 2019 Page 2 Exelon has reviewed the information supporting a finding of no significant hazard's consideration provided to the NRC in Reference 1. The additional information provided in this response does not affect the bases for concluding that the proposed license amendment does not involve a significant hazards consideration.

There are no regulatory commitments contained in this letter.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 301h day of October 2019.

If you should have any questions regarding this submittal, please contact Enrique Villar at 610-765-5736.

Respectfully, Pvf{,--j T,J_Jr--

David T. Gudger Senior Manager - Licensing Exelon Generation Company, LLC cc:

Regional Administrator, NRC Region I NRC Senior Resident Inspector NRC Project Manager D. A. Tancabel, State of Maryland