ML22173A038

NRR E-mail Capture - Request for Additional Information (RAI) Regarding Clinton License Amendment Request for Secondary Containment Design Basis (L-2022-LLA-0055)

ML22173A038
Person / Time
Site:	Clinton
Issue date:	06/21/2022
From:	Joel Wiebe NRC/NRR/DORL/LPL3
To:	Nicely K Exelon Generation Co
References
L-2022-LLA-0055
Download: ML22173A038 (3)

Text

From: Wiebe, Joel Sent: Tuesday, June 21, 2022 9:49 AM To: Nicely, Kenneth M:(Constellation Nuclear)

Subject:

Request for Additional Information (RAI) Regarding Clinton License Amendment Request for Secondary Containment Design Basis (L-2022-LLA-0055)

Hi Ken, These are preliminary RAIs. If you want a clarification call, let me know within one week. If a clarification call is not necessary, these RAIs will be considered final RAIs and a response is requested within 30 days.

Joel By application dated April 7, 2022, (Agencywide Documents Access and Management System Accession No. ML22097A208), Constellation Energy Generation, LLC (CEG), the licensee, submitted a license amendment request (LAR) to change the Clinton Power Station (CPS), Unit 1, design basis. Specifically, CEG requested approval for a change to the Updated Safety Analysis Report to support a revision of the CPS secondary containment design basis to credit the Fuel Building Railroad Airlock (FBRA) and FBRA outer door. The LAR Attachment 1, Evaluation of Proposed Change, discusses that no changes are needed to the CPS technical specifications (e.g., secondary containment technical specification) in order to credit the FBRA and the FBRA outer door as part of the secondary containment design basis.

Section 50.36, Technical Specifications, of Title 10 of the Code of Federal Regulations (10 CFR) describes the requirements related to the content of the technical specifications (TS).

Pursuant to 10 CFR 50.36(c), TS are required to include limiting conditions for operation (LCO).

Limiting conditions for operation are the lowest functional capability or performance levels of equipment required for safe operation of the facility.

CPS LCO Applicability requirement, LCO 3.0.9, addresses barriers which cannot perform their related support function for TS systems. For example, barriers are used to protect systems against missiles that are generated by external events. If a barrier cannot perform its related support function due to some type of failure or due to intentional removal to facilitate plant activities, the supported system(s) may be inoperable under the definition of OPERABILITY.

Note that LCO 3.0.9 may be concurrently applied to more than one train or subsystem of a multiple train or subsystem supported system provided at least one train or subsystem of the supported system is OPERABLE and the barriers supporting each of these trains or subsystems provide their related support function(s) for different categories of initiating events.

Based on LAR information described in Attachment 1, the FBRA inner door performs multiple safety functions including as a secondary containment boundary and as a barrier to tornado winds and missiles. While the proposed new boundary of the FBRA and outer door provides the secondary containment function, it does not provide the tornado barrier protection. If the FBRA inner door is unable to perform its barrier function, impacts to the equipment inside the Fuel Building due to lack of tornado protection would be assessed through the licensees Barrier Impairment Program and Corrective Action Program. However, the licensee did not provide information that explains whether or not the FBRA inner door would be subject to the provisions of CPS LCO 3.0.9.

The NRC staff has reviewed the information and determined that additional information is required to complete its review. The specific request is addressed below.

Discuss in detail CPS LCO 3.0.9 applicability to the FBRA inner door, including:

1. Explain whether or not the licensees Barrier Impairment Program cited in the LAR implements CPS LCO 3.0.9.

2. Explain whether or not the FBRA inner door is considered a barrier subject to the provisions of CPS LCO 3.0.9.

3. Explain whether or not CPS LCO 3.0.9 allowance is permitted with the FBRA inner door unable to function as a barrier.

4. If the FBRA inner door is unavailable to function as a barrier, identify the supported TS systems and equipment that would be impacted and identify the supported system LCOs, the applicable TS Conditions that would be entered for the supported systems and the associated Required Actions and Completion Times that would apply.

5. If the FBRA inner door is not considered a barrier subject to the provisions of CPS LCO 3.0.9, describe any programmatic controls or procedures that would limit the amount of time the inner door may remain open.

Hearing Identifier: NRR_DRMA Email Number: 1684 Mail Envelope Properties (MN2PR09MB497164E5C814050DACACF5B48BB39)

Subject:

Request for Additional Information (RAI) Regarding Clinton License Amendment Request for Secondary Containment Design Basis (L-2022-LLA-0055)

Sent Date: 6/21/2022 9:48:44 AM Received Date: 6/21/2022 9:48:00 AM From: Wiebe, Joel Created By: Joel.Wiebe@nrc.gov Recipients:

"Nicely, Kenneth M:(Constellation Nuclear)" <ken.nicely@constellation.com>

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