ML17277A205

Email - Ginna: Request for Additional Information (RAI) for NFPA-805 LAR

ML17277A205
Person / Time
Site:	Ginna
Issue date:	10/02/2017
From:	V Sreenivas Plant Licensing Branch 1
To:	David Helker, Tom Loomis Exelon Generation Co, Ginna
Sreenivas V, NRR/DORL/LPL1, 415-2596
References
Download: ML17277A205 (3)

Text

From: Sreenivas, V To: Loomis, Thomas R:(GenCo-Nuc) (thomas.loomis@exeloncorp.com); Helker, David P:(GenCo-Nuc)

Cc: Robinson, Jay; Hyslop, JS; Casto, Greg; Danna, James

Subject:

Ginna: Request for Additional Information (RAI) for NFPA-805 LAR that proposed to not complete modification, remove overcurrent protection for its emergency diesel generators Date: Monday, October 02, 2017 5:31:00 PM In its letter dated June 30, 2017, the licensee submitted a license amendment request (LAR) that proposed to not complete the modification to install overcurrent protection for its emergency diesel generators as required by its current fire protection license condition issued through amendment 119 on November 23, 2015 (ADAMS Accession No. ML15271A101). In order to complete its review, the U.S. Nuclear Regulatory Commission staff requests the following additional information:

RAI 1

The NRC staff found that the licensee proposed several additional changes unrelated to the proposed change to not install the overcurrent protection. The NRC staff is requesting that the licensee:

1. Clarify each of the proposed changes identified below in regards to whether NRC approval is being requested and provide additional justification/explanation for each proposed change.

2. Indicate whether each of the proposed changes identified below resulted in changes to the probabilistic risk assessment, and if so, provide the overall impact on risk for all changes in the LAR, and the impact on safety margin and defense-in-depth (DID) for each change to the plant leading to a change in the PRA, including changes to procedures. Indicate if the new risk results meet the acceptance guidelines of Regulatory Guide (RG) 1.174, An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant Specific Changes to the Licensing Basis, (ADAMS Accession No. ML100910006), and discuss the adequacy of the resulting safety margin and DID.

A. Enclosure C, Attachment C, Table C-1, Page C-2: The change from new charging system and standby charging pump to alternate RCS injection system and alternate RCS injection pump.

B. Enclosure C, Attachment G, Table G-1, Pages G-7 through G-12: The change in several recovery actions from new charging system new RCS injection system. In addition, this change does not align with the change described in A above.

C. Enclosure C, Attachment S, Tables S-1, S-2, and S-3:

a. The change that moved modifications 7 and 13 from Table S-2 to Table S-1.

b. The change from pressurizer to Reactor Coolant System in Modification 2 in Table S-2.

c. The change in ESR number in Modification 3 in Table S-2.

d. The change in ESR number and additional new text in Modification 4 in Table S-2.

e. The changed text in Modification 8 in Table S-2.

f. The changed text in Modification 9 in Table S-2.

g. The change that added implementation items 10, 11, 12, 13, 14, 23, and 24 to the list of implementation items that will be completed after modifications are

complete in Table S-3.

h. The changed text in Implementation Items 5, 20, and 24 in Table S-3.

RAI 2

In Enclosure 2, Attachment M, of its letter dated June 30, 2017, the licensee submitted its proposed changes to its fire protection license condition. The NRC staff identified the following errors:

A. The first paragraph used R.E. Ginna Nuclear Power Plant instead of Exelon Generation.

B. Transition license conditions 2 and 3 used CENG instead of Exelon Generation.

C. The June 30, 2017 LAR was not added to the first paragraph of the license condition.

D. A placeholder for the additional safety evaluation generated from June 30, 2017 LAR was not added to the first paragraph of the license condition.

The NRC staff requests that the licensee correct the identified errors and resubmit Attachment M.

RAI 3

The letter dated March 2, 2016 from Joseph G. Giitter, and Anne Boland, NRC, to Michael D. Tschiltz, Nuclear Energy Institute (NEI) (ADAMS Accession No. ML16015A416),

provided guidance for licensees to follow when seeking changes to license conditions established in amendments to adopt 10 CFR 50.48(c) (NFPA 805). In the letter, three options were provided. The licensees LAR dated June 30, 2017 did not indicate which option the licensee used in its submittal. However, Section 3.3 of this LAR does indicate those changes that have been made to the PRA model.

Aside from the changes identified in Section 3.3, please confirm that the LAR conforms to the criteria to meet Option A. If methods beyond those accepted in the Ginna NFPA 805 SE and beyond those in Section 3.3 were used, specify whether option B or C is appropriate for these additional methods.

RAI 4

In its LAR dated June 30, 2017, the licensee indicated that the heat release rates (HRRs) have been incorporated consistent with NUREG-2178, "Refining and Characterizing Heat Release Rates From Electrical Enclosures During Fire (RACHELLE-FIRE) - Volume 1:

Peak Heat Release Rates and Effect of Obstructed Plume, Final Report," April 2016, (ADAMS Accession No. ML16110A140), and that the data in NUREG-2178 offsets the risk increase associated with electrical cabinets.

The NRC staff requests that the licensee indicate if any electrical cabinets to which the obstructed plume model of NUREG-2178 is applied have the fire placed at an elevation of less than one-half of the cabinet. According to NUREG-2178, the obstructed plume model is not applicable to cabinets in which the fire is placed at elevations of less than one-half of the cabinet. Justify any cases where the obstructed plume model is credited where the fire is located at less than one half of the cabinets height, or remove credit for the obstructed plume model and recalculate the risk and compare it with RG 1.174 acceptance guidelines.

Please provide your response to these RAI by November 2, 2017. If you have any questions, please contact me at 301-415-2597.

V. Sreenivas, Ph.D., C.P.M.

Licensing Project Manager Limerick and Ginna, Plant Licensing Branch I Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation