NL-25-0197, Unit 4, Emergency License Amendment Request: One-Time Allowance to Repair Ves Bottled Air System Valve Leakage - Response to Request for Additional Information

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Unit 4, Emergency License Amendment Request: One-Time Allowance to Repair Ves Bottled Air System Valve Leakage - Response to Request for Additional Information
ML25137A002
Person / Time
Site: Vogtle Southern Nuclear icon.png
Issue date: 05/17/2025
From: Coleman J
Southern Nuclear Operating Co
To:
Office of Nuclear Reactor Regulation, Document Control Desk
References
NL-25-0197
Download: ML25137A002 (1)
v • d • e


Text

A Southern Nuclear May 17, 2025 Docket Nos.: 52-026 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Regulatory Affairs Southern Nuclear Operating Company Vogtle Electric Generating Plant - Unit 4 3535 Colonnade Parkway Birmingham, AL 35243 205 992 5000 NL-25-0197 10 CFR 50.90 Emergency License Amendment Request: One-Time Allowance to Repair VES Bottled Air System Valve Leakage - Response to Request for Additional Information Pursuant to 10 CFR 52.98(c) and in accordance with 10 CFR 50.90, Southern Nuclear Operating Company (SNC) requested an emergency amendment to the Combined License (COL) for Vogtle Electric Generating Plant (VEGP) Unit 4 (License Number NPF-92) on May 16, 2025. The license amendment request (LAR) proposed to revise COL Appendix A, Technical Specifications (TS) 3.7.6, Main Control Room Emergency Habitability System (VES) to add a one-time allowance to provide time to repair VES bottled air system valve leakage (ML25136A392). The request supplemented the SNC LAR submitted May 1, 2025 (ML25121A336).

On May 17, 2025, the NRC provided a request for additional information (RAI) to support their review of the request. Response to the RAI is provided in the Enclosure.

The response to the RAI does not impact the technical evaluation, regulatory evaluation (including the Significant Hazards Consideration), and environmental considerations for the proposed changes as provided in the requested license amendment.

This letter contains no regulatory commitments. This letter has been reviewed and determined not to contain security-related information.

In accordance with 10 CFR 50.91, SNC is notifying the State of Georgia by transmitting a copy of this letter and its enclosure to the designated State Official.

U. S. Nuclear Regulatory Commission NL-25-0197 Page 2 If you have any questions, please contact Ryan Joyce at (205) 992-6468.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 1 ?h of May, 2025.

Respectfully submitted,

Q~m~MM\\

Director, Regulatory Affairs Southern Nuclear Operating Company

Enclosure:

Response to Request for Additional Information cc:

NRC Regional Administrator, Region II NRR Project Manager - Vogtle 3 & 4 Senior Resident Inspector - Vogtle 3 & 4 Director, Environmental Protection Division - State of Georgia Document Services RTYPE: VND.LI.L00

Attachments:

Enclosure to NL-25-0197 Response to Request for Additional Information

1.

Revised Technical Specification Changes Marked-up Pages

2.

Revised Technical Specification Pages

3.

Revised Technical Specification Bases Marked-up Pages (for information only)

Enclosure to NL-25-0197 Response to Request for Additional Information NRC REQUEST The LAR states that the proposed change to TS 3.7.6 is based on design provisions that continue to support the MCR habitability during design basis events while crediting non-safety VBS and standby diesel generators. The proposed TS note does not include a requirement to ensure VBS is available during the one-time completion time extension, when VES has a complete loss of function. Without an explicit requirement in the TS for VBS to be available during the one-time completion time extension, the remedial actions permitted by the technical specifications are inadequate to ensure sufficient safety margins are maintained. Provide additional justification for not including VBS in the proposed note or update the note to include VBS.

SNC RESPONSE SNC agrees that explicit discussion would be clearer and proposes the revised NOTE to read:

For one-time use on Unit 4, initiation of Required Actions F.1 and F.2 Completion Times may be delayed for 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> from discovery of Condition F entry when Condition F entry is a result of VES air system leakage repair(s) 1 provided VBS is providing ventilation to the main control room envelope. This provision expires 124 hours0.00144 days <br />0.0344 hours <br />2.050265e-4 weeks <br />4.7182e-5 months <br /> following NRC approval.

E-1 Technical Specification Changes Marked-up Pages Revised Technical Specification Changes Marked-up Pages Insertions Denoted by underlined Blue text

ACTIONS (continued)

CONDITION F.

Required Action and associated Completion Time of Condition A, B, C, D, or E not met in MODE 1, 2, 3, or 4.

OR VES inoperable for reasons other than Condition A, B, C, D, or E in MODE 1, 2, 3, or 4.

G.

Required Action and associated Completion Time of Condition A, B, C, or E not met during movement of irradiated fuel.

OR VES inoperable for reasons other than Condition A, B, C, or E during movement of irradiated fuel.

OR VES inoperable due to inoperable MCRE boundary during movement of irradiated fuel.

VEGP Units 3 and 4 Technical Specifications REQUIRED ACTION

NOTE-------------------

For one-time use on Unit 4, initiation of Reguired Actions F.1 and F.2 Com12letion Times may be delayed for 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> from discove[Y of Condition F entrv when Condition F ent[Y is a result of VES air system leakage re12air(s}, 12rovided VBS is 12roviding ventilation to the main control room envelo12e. This 12rovision ex12ires 124 hours0.00144 days <br />0.0344 hours <br />2.050265e-4 weeks <br />4.7182e-5 months <br /> following NRC a1212roval.

F.1 Be in MODE 3.

AND F.2 Be in MODE 5.

G.1 Suspend movement of irradiated fuel assemblies.

VES 3.7.6 COMPLETION TIME 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 36 hours Immediately 3.7.6 - 3 Amendment No. 108 (Unit 3)

Amendment No.1 97G+ (Unit 4)

Revised Technical Specification Pages Revised Technical Specification Pages

ACTIONS (continued)

CONDITION F.

Required Action and associated Completion Time of Condition A, B, C, D, or E not met in MODE 1, 2, 3, or 4.

OR VES inoperable for reasons other than Condition A, B, C, D, or E in MODE 1, 2, 3, or 4.

G.

Required Action and associated Completion Time of Condition A, B, C, or E not met during movement of irradiated fuel.

OR VES inoperable for reasons other than Condition A, B, C, or E during movement of irradiated fuel.

OR VES inoperable due to inoperable MCRE boundary during movement of irradiated fuel.

VEGP Units 3 and 4 Technical Specifications REQUIRED ACTION

NOTE-------------------

For one-time use on Unit 4, initiation of Required Actions F.1 and F.2 Completion Times may be delayed for 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> from discovery of Condition F entry when Condition F entry is a result of VES air system leakage repair(s), provided VBS is providing ventilation to the main control room envelope. This provision expires 124 hours0.00144 days <br />0.0344 hours <br />2.050265e-4 weeks <br />4.7182e-5 months <br /> following NRC approval.

F.1 Be in MODE 3.

AND F.2 Be in MODE 5.

G.1 Suspend movement of irradiated fuel assemblies.

VES 3.7.6 COMPLETION TIME 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 36 hours Immediately 3.7.6 - 3 Amendment No. 108 (Unit 3)

Amendment No. 197 (Unit 4)

Technical Specification Bases Marked-up Pages (For Information Only)

Revised Technical Specification Bases Marked-up Pages (For Information Only)

Insertions Denoted by underlined Blue text

Technical Specifications Bases BASES VES B 3.7.6 ACTIONS (continued)

SURVEILLANCE REQUIREMENTS VEGP Units 3 and 4 F.1 and F.2 In MODE 1, 2, 3, or 4 if the Required Actions and Completion Times of Condition A, B, C, D, or E are not met, or the VES is inoperable for reasons other than Condition A, B, C, D, or E (e.g., with compressed air storage tanks containing ::; 245,680 scf, the equivalent of more than one bank inop), the unit must be placed in a MODE in which the LCO does not apply. To achieve this status, the unit must be placed in at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.

Required Actions F.1 and F.2 are modified by a Note allowing a modified time zero for one-time use on Unit 4, provided VBS is providing ventilation to the main control room envelope. In this event, initiation of the Required Actions F.1 and F. 2 Completion Times may be delayed for 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> from discovery of Condition F entry when Condition F entry is a result of VES air system leakage repair(s). The allowance is also intended to be applicable when Condition F is entered from failure to meet Required Action E.1 in its associated Completion Time due to an unplanned increased air leakage that results in the need to initiate repair(s). This provision expires 124 hours0.00144 days <br />0.0344 hours <br />2.050265e-4 weeks <br />4.7182e-5 months <br /> following NRC approval, i.e., the NRC safety evaluation is issued approving the amendment request that adds this Note. During this allowance one train of VBS and the associated standby diesel generator are "protected."

G.1 During movement of irradiated fuel assemblies, if the Required Actions and Completion Times of Condition A, B, C, or E are not met, or the VES is inoperable for reasons other than Condition A, B, C, or E, or the VES is inoperable due to an inoperable MCRE boundary, action must be taken immediately to suspend the movement of fuel. This does not preclude the movement of fuel to a safe position.

SR 3.7.6.1 Verification every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> that compressed air storage tanks contain

> 327,574 scf of breathable air.

The standard volume is determined using the compressed air storage tank room temperature (VAS-TE-080A/B) and compressed air storage tanks pressure (VES-PT-001A/B) via the plant control system and chart in the system procedures. Verification that the minimum volume of compressed air is contained in the compressed air storage tanks ensures that there will be an adequate supply of breathable air to maintain MCRE B3.7.6-11 Revision 87+:J

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