ML25316A170

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Application to Revise Technical Specifications to Adopt TSTF-567-A, Rev. 1, Add Containment Sump TS to Address GSI-191 Issues
ML25316A170
Person / Time
Site: North Anna  Dominion icon.png
Issue date: 11/07/2025
From: James Holloway
Dominion Energy Virginia, Virginia Electric & Power Co (VEPCO)
To:
Office of Nuclear Reactor Regulation, Document Control Desk
References
24-031
Download: ML25316A170 (1)
v • d • e


Text

Dominion Energy Virginia 5000 Dominion Boulevard, Glen Allen, VA 23060 DominionEnergy.com 10 CFR 50.90 September 9, 2021 U. S. Nuclear Regulatory Commission Serial No.:

24-031 ATTN: Document Control Desk NRA/JHH:

R0 Washington, DC 20555-0001 Docket Nos.:

50-338 50-339 License Nos.: NPF-4 NPF-7 VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION ENERGY VIRGINIA)

NORTH ANNA POWER STATION UNITS 1 AND 2 APPLICATION TO REVISE TECHNICAL SPECIFICATIONS TO ADOPT TSTF-567-A, REV 1, "ADD CONTAINMENT SUMP TS TO ADDRESS GSI-191 ISSUES Pursuant to 10 CFR 50.90, Virginia Electric and Power Company (Dominion Energy Virginia) is submitting a request for an amendment to the Technical Specifications (TS) for North Anna Power Station (NAPS), Units 1 and 2.

Dominion Energy Virginia requests adoption of Technical Specification Task Force (TSTF) Traveler TSTF-567-A, Revision 1, Add Containment Sump TS to Address GSI-191 Issues, which is an approved change to the Improved Standard Technical Specifications (ISTS), into the NAPS Unit 1 and Unit 2 TS. The proposed amendment adds a new TS 3.6.9, Containment Sump, and adds an Action to address the condition of the containment sump made inoperable due to containment accident generated and transported debris exceeding the analyzed limits. The Action provides time to correct or evaluate the condition in lieu of an immediate plant shutdown.

The enclosure provides a description and assessment of the proposed changes. provides the existing NAPS Units 1 and 2 TS pages marked to show the proposed changes. Attachment 2 provides revised (clean) TS changes. Attachment 3 provides existing TS Bases pages marked to show the proposed changes for information only. The Facility Safety Review Committee has reviewed and concurred with the determinations herein.

Serial No.: 24-031 Docket Nos.: 50-338/50-339 Page 2 of 3 Dominion Energy Virginia requests that the amendment be reviewed under the Consolidated Line Item Improvement Process (CLIIP). Approval of the amendment is requested within six months of completion of the NRCs acceptance review. Once approved, the amendment shall be implemented within 60 days.

In accordance with 10 CFR 50.91, a copy of this application, with attachments, is being provided to the designated Virginia Official.

Should you have any questions or require additional information, please contact Julie Hough at 804-273-3586.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on.

Sincerely, James E. Holloway Vice President - Nuclear Engineering & Fleet Support

Enclosure:

Description and Assessment of Proposed Change Attachments:

1. Proposed Technical Specification Changes (Mark-Ups)
2. Revised Technical Specification Pages
3. Proposed Technical Specification Bases Changes (Mark-Ups) For Information Only Commitments made by this letter: None cc: See next page

Serial No.: 24-031 Docket Nos.: 50-338/50-339 Page 3 of 3 cc: Regional Administrator, Region II U. S. Nuclear Regulatory Commission Mr. G. E. Miller Senior Project Manager - North Anna Power Station U. S. Nuclear Regulatory Commission NRC Senior Resident Inspector North Anna Power Station Old Dominion Electric Cooperative R-North-Anna-Correspondence@odec.com State Health Commissioner Virginia Department of Health James Madison Building - 7th floor 109 Governor Street, Suite 730 Richmond, Virginia 23219

Serial No.: 24-031 Docket Nos.: 50-338/339 ENCLOSURE Description and Assessment of Proposed Change Virginia Electric and Power Company (Dominion Energy Virginia)

North Anna Power Station Unit 1 and Unit 2

Serial No.: 24-031 Docket Nos.: 50-338/339, Page 1 of 5 DESCRIPTION AND ASSESSMENT

1.0 DESCRIPTION

Virginia Electric and Power Company (Dominion Energy Virginia) requests adoption of Technical Specification Task Force (TSTF) Traveler 567-A, Revision 1, Add Containment Sump TS to address GSI-191 Issues, which is an approved change to the Improved Standard Technical Specifications (ISTS), into the North Anna Power Station (NAPS) Unit 1 and 2 Technical Specifications (TSs).

The proposed change adds a new Technical Specification (TS) 3.6.9, Containment Sump, which includes an Action to address the condition of the containment sump made inoperable due to containment generated and transported debris exceeding the analyzed limits. The Action provides time to correct or evaluate the condition in lieu of an immediate plant shutdown. This Action is placed in a new specification on the containment sump that otherwise retains the existing Technical Specification requirements. Two existing Surveillance Requirements (SRs) are moved from TS 3.5.2, ECCS [Emergency Core Cooling System] - Operating, and TS 3.6.7, Recirculation (RS) Spray, to the new specification. The requirement to perform SR 3.5.2.8 in TS 3.5.3, ECCS - Shutdown, is deleted.

2.0 ASSESSMENT

2.1 Applicability of Safety Evaluation Dominion Energy Virginia has reviewed the safety evaluation for TSTF-567-A, Revision 1, provided to the TSTF in a letter dated July 3, 2018. This included a review of the NRCs staff evaluation, as well as the information provided in TSTF-567-A, Revision 1. Dominion Energy Virginia has concluded that the justifications presented in TSTF-567-A, Revision 1 and the safety evaluation prepared by the NRC staff are applicable to NAPS Units 1 and 2 and justify this amendment for the incorporation of the changes into NAPS Units 1 and 2 TSs.

2.2 Variations Dominion Energy Virginia is requesting the following variations from the TS changes described in TSTF-567 or the applicable parts of the NRC staff safety evaluation.

These variations do not affect the applicability of TSTF-567 or the NRC staff safety evaluation.

The NAPS Units 1 and 2 TS use different TS numbering than the ISTS on which TSTF-567-A, Revision 1, was based. Specifically, TSTF-567-A, Revision 1, identifies the new sump TS as 3.6.19. For NAPS Units 1 and 2, this new TS is numbered 3.6.9. This difference is administrative and does not affect the applicability of TSTF-567-A, Revision 1, to NAPS Units 1 and 2.

Serial No.: 24-031 Docket Nos.: 50-338/339, Page 2 of 5 Section 3.3.4 of the Final Safety Evaluation for TSTF-567, Revision 1, notes that the Completion Time for required action B.1 for the new Containment Sump TS should be the same as the TS 3.6.6 Completion Time for a single inoperable Containment Spray and Cooling System (CSS) train (typically 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or 7 days), since the ECCS and CSS TS Actions should control the licensees response. Because NAPS Units 1 and 2 have subatmospheric containments, the NAPS TSs do not contain a CSS TS and instead contain Quench Spray and RS TSs. The equivalent TS to identify the Completion Time for required action B.1 is TS 3.6.7, Recirculation Spray, as the RS system takes suction from the containment sump. Therefore, the proposed Completion Time for TS 3.6.9, Action B.1 is 7 days, the same as the Limiting Condition for Operation (LCO) 3.6.7 Completion Time for a single inoperable RS train.

The NAPS TS contain a Surveillance Frequency Control Program. Therefore, the Frequency for SR 3.6.9.1 will be In accordance with the Surveillance Frequency Control Program.

NAPS Units 1 and 2 both have a single sump with two strainers; 1) a lower strainer that is attached to the containment basement floor from which both trains of the RS system take suction, and 2) an upper strainer that is attached on top of the RS strainer, from which both trains of the ECCS Low Head Safety Injection (LHSI) pumps take suction during the recirculation phase (i.e.,

recirculation mode transfer or sump switchover). The single sump is common to both strainers in each unit. NAPS Units 1 and 2 TS SR 3.5.2.8 requires inspection of the ECCS strainers, and SR 3.6.7.7 requires inspection of the RS system strainers. TSTF-567 does not contain the SR 3.6.7.7 inspection requirement, which is unique to NAPS and differs from the ISTS on which TSTF-567 was based. This difference does not alter the conclusion that the proposed change is applicable to NAPS, as both the RS system and ECCS sump components will be inspected though performance of new SR 3.6.9.1.

A reference to pump suction trash racks in the TSTF-567 model application section for the TS Bases, B 3.6.19, LCO is omitted from the NAPS TS 3.6.9 Bases. The NAPS Units 1 and 2 containment sumps do not have pump suction trash racks. This difference does not alter the conclusion that TSTF-567 is applicable to NAPS.

NAPS Units 1 and 2 have adopted TSTF-575, Revise TS 3.5.3, ECCS -

Shutdown Bases, which revised the TS 3.5.3 Bases to be consistent with the licensing and design bases as described in the Final Safety Analysis Report. As a part of this change, the TS 3.5.2 Bases Background statement that the accumulators and refueling water storage tank are part of the ECCS, but not considered a part of the ECCS flow path as described by the LCO, was copied from the TS 3.5.2 Bases Background section to the TS 3.5.3 Bases Background section. This statement is revised in the Background of the TS 3.5.2 and TS 3.5.3 Bases to clarify that the Containment Sump is also a part of the ECCS but not described by the ECCS flow path as described in TS 3.5.2 and TS 3.5.3.

Serial No.: 24-031 Docket Nos.: 50-338/339, Page 3 of 5 The TS 3.5.3 Bases Background is also revised to clarify that the ECCS flowpath includes containment sump recirculation, if needed.

3.0 REGULATORY ANALYSIS

3.1 No Significant Hazards Consideration Analysis The proposed amendment adds a new Technical Specification (TS) 3.6.9, Containment Sump, and adds an Action to address the condition of the containment sump made inoperable due to containment accident generated and transported debris exceeding the analyzed limits. The Action provides time to correct or evaluate the condition in lieu of an immediate plant shutdown. This Action is placed in a new specification on the containment sump that otherwise retains the existing Technical Specifications requirements. Two existing SRs are moved from TS 3.5.2 and TS 3.6.7 to the new specification. The requirement to perform SR 3.5.2.8 in TS 3.5.3 is deleted.

Dominion Energy Virginia has evaluated whether a significant hazards consideration is involved with the proposed amendment(s) by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:

1.

Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No The proposed change adds a new specification to the TS for the containment sump. Two existing SRs on the containment sump are moved from TS 3.5.2 and TS 3.6.7 to the new specification and a duplicative requirement to perform the SR 3.5.2.8 in T.S. 3.5.3 is removed. The new specification retains the existing requirements on the containment sump and the actions to be taken when the containment sump is inoperable with the exception of adding new actions to be taken when the containment sump is inoperable due to containment accident generated and transported debris exceeding the analyzed limits. The new action provides time to evaluate and correct the condition instead of requiring an immediate plant shutdown.

The containment sump is not an initiator of any accident previously evaluated. The containment sump is a passive component, and the proposed change does not increase the likelihood of a malfunction. As a result, the probability of an accident is unaffected by the proposed change.

The containment sump is used to mitigate accidents previously evaluated by providing a borated water source for the ECCS and RS systems. The design of the containment sump and the capability of the containment sump assumed in the accident analysis is not changed. The proposed action requires implementation of mitigating actions while the containment sump is inoperable and more frequent monitoring of reactor coolant leakage to detect any increased potential for an accident that would require the containment sump. The consequences of an

Serial No.: 24-031 Docket Nos.: 50-338/339, Page 4 of 5 accident during the proposed action are no different than the current consequences of an accident if the containment sump is inoperable.

Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2)

Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No.

The proposed change adds a new specification to the TS for the containment sump. Two existing SRs on the containment sump are moved from TS 3.5.2 and TS 3.6.7 to the new specification and a duplicative requirement to perform SR 3.5.2.8 in TS 3.5.3 is removed. The new specification retains the existing requirements on the containment sump and the actions to be taken when the containment sump is inoperable with the exception of adding new actions to be taken when the containment sump is inoperable due to containment accident generated and transported debris exceeding the analyzed limits. The new action provides time to evaluate and correct the condition instead of requiring an immediate plant shutdown.

The proposed change does not alter the design or design function of the containment sump or the plant. No new systems are installed or removed as part of the proposed change. The containment sump is a passive component and cannot initiate a malfunction or accident. No new credible accident is created that is not encompassed by the existing accident analyses that assume the function of the containment sump.

Therefore, the proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.

3)

Does the proposed amendment involve a significant reduction in a margin of safety?

Response: No.

The proposed change adds a new specification to the TS for the containment sump. Two existing SRs on the containment sump are moved from TS 3.5.2 and TS 3.6.7 to the new specification and a duplicative requirement to perform SR 3.5.2.8 in TS 3.5.3 is removed. The new specification retains the existing requirements on the containment sump and the actions to be taken when the containment sump is inoperable with the exception of adding new actions to be taken when the containment sump is inoperable due to containment accident generated and transported debris exceeding the analyzed limits. The new action provides time to evaluate and correct the condition instead of requiring an immediate plant shutdown.

Serial No.: 24-031 Docket Nos.: 50-338/339, Page 5 of 5 The proposed change does not affect the controlling values of parameters used to avoid exceeding regulatory or licensing limits. No Safety Limits are affected by the proposed change. The proposed change does not affect any assumptions in the accident analyses that demonstrate compliance with regulatory and licensing requirements.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above, Dominion Energy Virginia concludes that the proposed amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.

3.2 Conclusion In conclusion, based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

4.0 ENVIRONMENTAL CONSIDERATION

A review has determined that the proposed amendment would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement.

However, the proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or a significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9).

Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

Serial No.: 24-031 Docket Nos.: 50-338/339 ATTACHMENT 1 Proposed Technical Specification Changes (Mark-Ups)

Virginia Electric and Power Company (Dominion Energy Virginia)

North Anna Power Station Unit 1 and Unit 2

North Anna Units 1 and 2 ii Amendments 255/236 TECHNICAL SPECIFICATIONS TABLE OF CONTENTS 3.4 REACTOR COOLANT SYSTEM (RCS) (continued) 3.4.7 RCS Loops³MODE 5, Loops Filled........... 3.4.7-1 3.4.8 RCS Loops³MODE 5, Loops Not Filled......... 3.4.8-1 3.4.9 Pressurizer..................... 3.4.9-1 3.4.10 Pressurizer Safety Valves..............3.4.10-1 3.4.11 Pressurizer Power Operated Relief Valves (PORVs).....................3.4.11-1 3.4.12 Low Temperature Overpressure Protection (LTOP)

System.....................3.4.12-1 3.4.13 RCS Operational LEAKAGE...............3.4.13-1 3.4.14 RCS Pressure Isolation Valve (PIV) Leakage.....3.4.14-1 3.4.15 RCS Leakage Detection Instrumentation........3.4.15-1 3.4.16 RCS Specific Activity................3.4.16-1 3.4.17 RCS Loop Isolation Valves..............3.4.17-1 3.4.18 RCS Isolated Loop Startup..............3.4.18-1 3.4.19 RCS Loops³Test Exceptions..............3.4.19-1 3.4.20 Steam Generator (SG) Tube Integrity.........3.4.20-1 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS).......... 3.5.1-1 3.5.1 Accumulators.................... 3.5.1-1 3.5.2 ECCS³Operating................... 3.5.2-1 3.5.3 ECCS³Shutdown.................... 3.5.3-1 3.5.4 Refueling Water Storage Tank (RWST)......... 3.5.4-1 3.5.5 Seal Injection Flow................. 3.5.5-1 3.5.6 Boron Injection Tank (BIT)............. 3.5.6-1 3.6 CONTAINMENT SYSTEMS................... 3.6.1-1 3.6.1 Containment..................... 3.6.1-1 3.6.2 Containment Air Locks................ 3.6.2-1 3.6.3 Containment Isolation Valves............ 3.6.3-1 3.6.4 Containment Pressure................ 3.6.4-1 3.6.5 Containment Air Temperature............. 3.6.5-1 3.6.6 Quench Spray (QS) System.............. 3.6.6-1 3.6.7 Recirculation Spray (RS) System........... 3.6.7-1 3.6.8 Chemical Addition System.............. 3.6.8-1 3.7 PLANT SYSTEMS...................... 3.7.1-1 3.7.1 Main Steam Safety Valves (MSSVs).......... 3.7.1-1 3.7.2 Main Steam Trip Valves (MSTVs)........... 3.7.2-1 3.7.3 Main Feedwater Isolation Valves (MFIVs), Main Feedwater Pump Discharge Valves (MFPDVs),

Main Feedwater Regulating Valves (MFRVs),

and Main Feedwater Regulating Bypass Valves (MFRBVs).................... 3.7.3-1 3.7.4 Steam Generator Power Operated Relief Valves (SG PORVs)................... 3.7.4-1 3.7.5 Auxiliary Feedwater (AFW) System.......... 3.7.5-1 3.7.6 Emergency Condensate Storage Tank (ECST)...... 3.7.6-1 3.7.7 Secondary Specific Activity............. 3.7.7-1 3.7.8 Service Water (SW) System.............. 3.7.8-1 Serial No.24-031 Docket Nos: 50-338/339

, Page 1 of 8

ECCS³Operating 3.5.2 North Anna Units 1 and 2 3.5.2-3 Amendments 262/243 SURVEILLANCE FREQUENCY SR 3.5.2.5 Verify each ECCS automatic valve in the flow path that is not locked, sealed, or otherwise secured in position, actuates to the correct position on an actual or simulated actuation signal.

In accordance with the Surveillance Frequency Control Program SR 3.5.2.6 Verify each ECCS pump capable of starting automatically starts automatically on an actual or simulated actuation signal.

In accordance with the Surveillance Frequency Control Program SR 3.5.2.7 Verify each ECCS throttle valve listed below is secured in the correct position.

Unit 1 Valve Number Unit 2 Valve Number 1-SI-188 2-SI-89 1-SI-191 2-SI-97 1-SI-193 2-SI-103 1-SI-203 2-SI-116 1-SI-204 2-SI-111 1-SI-205 2-SI-123 In accordance with the Surveillance Frequency Control Program SR 3.5.2.8 Verify, by visual inspection, each ECCS train containment sump component is not restricted by debris and shows no evidence of structural distress or abnormal corrosion.

In accordance with the Surveillance Frequency Control Program SURVEILLANCE REQUIREMENTS Serial No.24-031 Docket Nos: 50-338/339

, Page 2 of 8

ECCS³Shutdown 3.5.3 North Anna Units 1 and 2 3.5.3-1 Amendments 231/212 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) 3.5.3 ECCS³Shutdown LCO 3.5.3 One ECCS train shall be OPERABLE.

APPLICABILITY:

MODE 4.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

Required ECCS train inoperable.

A.1 Restore required ECCS train to OPERABLE status.

1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> B.

Required Action and associated Completion Time not met.

B.1 Be in MODE 5.

24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.3.1 The following SRs are applicable for all equipment required to be OPERABLE:

SR 3.5.2.1 SR 3.5.2.7 SR 3.5.2.3 SR 3.5.2.8 SR 3.5.2.4 In accordance with applicable SRs Serial No.24-031 Docket Nos: 50-338/339

, Page 3 of 8

RS System 3.6.7 North Anna Units 1 and 2 3.6.7-3 Amendments 262/243 SURVEILLANCE FREQUENCY SR 3.6.7.4 Verify each RS and casing cooling manual, power operated, and automatic valve in the flow path that is not locked, sealed, or otherwise secured in position is in the correct position.

In accordance with the Surveillance Frequency Control Program SR 3.6.7.5 Verify each RS and casing cooling pump's developed head at the flow test point is greater than or equal to the required developed head.

In accordance with the Inservice Testing Program SR 3.6.7.6 Verify on an actual or simulated actuation signal(s):

a. Each RS automatic valve in the flow path that is not locked, sealed, or otherwise secured in position, actuates to the correct position;
b. Each RS pump starts automatically; and
c. Each casing cooling pump starts automatically.

In accordance with the Surveillance Frequency Control Program SR 3.6.7.7 Verify, by visual inspection, each RS train containment sump component is not restricted by debris and shows no evidence of structural distress or abnormal corrosion.

In accordance with the Surveillance Frequency Control Program SR 3.6.7.8 Verify each spray nozzle is unobstructed.

Following maintenance which could cause nozzle blockage SURVEILLANCE REQUIREMENTS 7

Serial No. 24-03 Docket Nos: 50-338/339

, Page 4 of 8

Chemical Addition System 3.6.8 North Anna Units 1 and 2 3.6.8-2 Amendments 295/278 SURVEILLANCE FREQUENCY SR 3.6.8.2 Verify that the sodium tetraborate baskets collectively contain 16,013 lbm and 22,192 lbm of sodium tetraborate decahydrate.

In accordance with the Surveillance Frequency Control Program SR 3.6.8.3 Verify that a sample from the sodium tetraborate decahydrate baskets provides adequate pH adjustment of borated water.

In accordance with the Surveillance Frequency Control Program SURVEILLANCE REQUIREMENTS Serial No.24-031 Docket Nos: 50-338/339

, Page 5 of 8

Containment Sump 3.6.9 North Anna Units 1 and 2 3.6.9-1 Amendments /

Serial No.24-031 Docket Nos. 50-338/339 Attachment, Page 6 of 8 3.6 CONTAINMENT SYSTEMS 3.6.9 Containment Sump LCO 3.6.9 The containment sump shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, 3, and 4.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. Containment sump inoperable due to containment accident generated and transported debris exceeding the analyzed limits.

A.1 Initiate action to mitigate containment accident generated and transported debris.

AND A.2 Perform SR 3.4.13.1.

AND A.3 Restore the containment sump to OPERABLE status.

Immediately Once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 90 days

Containment Sump 3.6.9 North Anna Units 1 and 2 3.6.9-2 Amendments /

Serial No.24-031 Docket Nos. 50-338/339 Attachment, Page 7 of 8 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B. Containment sump inoperable for reasons other than Condition A.

B.1

NOTES------------

1.

Enter applicable Conditions and Required Actions of LCO 3.5.2, "ECCS -

Operating," and LCO 3.5.3, "ECCS -

Shutdown," for emergency core cooling trains made inoperable by the containment sump.

2.

Enter applicable Conditions and Required Actions of LCO 3.6.7, Recirculation Spray (RS)," for recirculation spray trains made inoperable by the containment sump.

Restore the containment sump to OPERABLE status.

7 days C. Required Action and associated Completion Time not met.

C.1 Be in MODE 3.

AND C.2 Be in MODE 5.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 36 hours

Containment Sump 3.6.9 North Anna Units 1 and 2 3.6.9-3 Amendments /

Serial No.24-031 Docket Nos. 50-338/339 Attachment, Page 8 of 8 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.9.1 Verify, by visual inspection, the containment sump does not show structural damage, abnormal corrosion, or debris blockage.

In accordance with the Surveillance Frequency Control Program

Serial No.: 24-031 Docket Nos.: 50-338/339 ATTACHMENT 2 Revised Technical Specification Pages Virginia Electric and Power Company (Dominion Energy Virginia)

North Anna Power Station Unit 1 and Unit 2

North Anna Units 1 and 2 ii Amendments TECHNICAL SPECIFICATIONS TABLE OF CONTENTS 3.4 REACTOR COOLANT SYSTEM (RCS) (continued) 3.4.7 RCS Loops³MODE 5, Loops Filled........... 3.4.7-1 3.4.8 RCS Loops³MODE 5, Loops Not Filled......... 3.4.8-1 3.4.9 Pressurizer..................... 3.4.9-1 3.4.10 Pressurizer Safety Valves..............3.4.10-1 3.4.11 Pressurizer Power Operated Relief Valves (PORVs).....................3.4.11-1 3.4.12 Low Temperature Overpressure Protection (LTOP)

System.....................3.4.12-1 3.4.13 RCS Operational LEAKAGE...............3.4.13-1 3.4.14 RCS Pressure Isolation Valve (PIV) Leakage.....3.4.14-1 3.4.15 RCS Leakage Detection Instrumentation........3.4.15-1 3.4.16 RCS Specific Activity................3.4.16-1 3.4.17 RCS Loop Isolation Valves..............3.4.17-1 3.4.18 RCS Isolated Loop Startup..............3.4.18-1 3.4.19 RCS Loops³Test Exceptions..............3.4.19-1 3.4.20 Steam Generator (SG) Tube Integrity.........3.4.20-1 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS).......... 3.5.1-1 3.5.1 Accumulators.................... 3.5.1-1 3.5.2 ECCS³Operating................... 3.5.2-1 3.5.3 ECCS³Shutdown.................... 3.5.3-1 3.5.4 Refueling Water Storage Tank (RWST)......... 3.5.4-1 3.5.5 Seal Injection Flow................. 3.5.5-1 3.5.6 Boron Injection Tank (BIT)............. 3.5.6-1 3.6 CONTAINMENT SYSTEMS................... 3.6.1-1 3.6.1 Containment..................... 3.6.1-1 3.6.2 Containment Air Locks................ 3.6.2-1 3.6.3 Containment Isolation Valves............ 3.6.3-1 3.6.4 Containment Pressure................ 3.6.4-1 3.6.5 Containment Air Temperature............. 3.6.5-1 3.6.6 Quench Spray (QS) System.............. 3.6.6-1 3.6.7 Recirculation Spray (RS) System........... 3.6.7-1 3.6.8 Chemical Addition System.............. 3.6.8-1 3.6.9 Containment Sump.................. 3.6.9-1 3.7 PLANT SYSTEMS...................... 3.7.1-1 3.7.1 Main Steam Safety Valves (MSSVs).......... 3.7.1-1 3.7.2 Main Steam Trip Valves (MSTVs)........... 3.7.2-1 3.7.3 Main Feedwater Isolation Valves (MFIVs), Main Feedwater Pump Discharge Valves (MFPDVs),

Main Feedwater Regulating Valves (MFRVs),

and Main Feedwater Regulating Bypass Valves (MFRBVs).................... 3.7.3-1 3.7.4 Steam Generator Power Operated Relief Valves (SG PORVs)................... 3.7.4-1 3.7.5 Auxiliary Feedwater (AFW) System.......... 3.7.5-1 3.7.6 Emergency Condensate Storage Tank (ECST)...... 3.7.6-1 3.7.7 Secondary Specific Activity............. 3.7.7-1 Serial No.24-031 Docket Nos: 50-338/339, Page 1 of 7

ECCS³Operating 3.5.2 North Anna Units 1 and 2 3.5.2-3 Amendments SURVEILLANCE FREQUENCY SR 3.5.2.5 Verify each ECCS automatic valve in the flow path that is not locked, sealed, or otherwise secured in position, actuates to the correct position on an actual or simulated actuation signal.

In accordance with the Surveillance Frequency Control Program SR 3.5.2.6 Verify each ECCS pump capable of starting automatically starts automatically on an actual or simulated actuation signal.

In accordance with the Surveillance Frequency Control Program SR 3.5.2.7 Verify each ECCS throttle valve listed below is secured in the correct position.

Unit 1 Valve Number Unit 2 Valve Number 1-SI-188 2-SI-89 1-SI-191 2-SI-97 1-SI-193 2-SI-103 1-SI-203 2-SI-116 1-SI-204 2-SI-111 1-SI-205 2-SI-123 In accordance with the Surveillance Frequency Control Program SURVEILLANCE REQUIREMENTS Serial No.24-031 Docket Nos: 50-338/339, Page 2 of 7

ECCS³Shutdown 3.5.3 North Anna Units 1 and 2 3.5.3-1 Amendments 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) 3.5.3 ECCS³Shutdown LCO 3.5.3 One ECCS train shall be OPERABLE.

APPLICABILITY:

MODE 4.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

Required ECCS train inoperable.

A.1 Restore required ECCS train to OPERABLE status.

1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> B.

Required Action and associated Completion Time not met.

B.1 Be in MODE 5.

24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.3.1 The following SRs are applicable for all equipment required to be OPERABLE:

SR 3.5.2.1 SR 3.5.2.7 SR 3.5.2.3 SR 3.5.2.4 In accordance with applicable SRs Serial No.24-031 Docket Nos: 50-338/339, Page 3 of 7

RS System 3.6.7 North Anna Units 1 and 2 3.6.7-3 Amendments SURVEILLANCE FREQUENCY SR 3.6.7.4 Verify each RS and casing cooling manual, power operated, and automatic valve in the flow path that is not locked, sealed, or otherwise secured in position is in the correct position.

In accordance with the Surveillance Frequency Control Program SR 3.6.7.5 Verify each RS and casing cooling pump's developed head at the flow test point is greater than or equal to the required developed head.

In accordance with the Inservice Testing Program SR 3.6.7.6 Verify on an actual or simulated actuation signal(s):

a. Each RS automatic valve in the flow path that is not locked, sealed, or otherwise secured in position, actuates to the correct position;
b. Each RS pump starts automatically; and
c. Each casing cooling pump starts automatically.

In accordance with the Surveillance Frequency Control Program SR 3.6.7.7 Verify each spray nozzle is unobstructed.

Following maintenance which could cause nozzle blockage SURVEILLANCE REQUIREMENTS Serial No.24-031 Docket Nos: 50-338/339, Page 4 of 7

Containment Sump 3.6.9 North Anna Units 1 and 2 3.6.9-1 Amendments 3.6 CONTAINMENT SYSTEMS 3.6.9 Containment Sump LCO 3.6.9 The Containment Sump shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, 3, and 4.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

Containment sump inoperable due to containment accident generated and transported debris exceeding the analyzed limits.

A.1 Initiate action to mitigate containment accident generated and transported debris.

AND A.2 Perform SR 3.4.13.1.

AND A.3 Restore the containment sump to OPERABLE status.

Immediately Once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 90 days Serial No.24-031 Docket Nos: 50-338/339, Page 5 of 7

Containment Sump 3.6.9 North Anna Units 1 and 2 3.6.9-2 Amendments CONDITION REQUIRED ACTION COMPLETION TIME B.

Containment sump inoperable for reasons other than Condition A.

B.1 ---------NOTES-----------

1. Enter applicable Conditions and Required Actons of LCO 3,5,2, 'ECCS -

Operating,µ and LCO 3.5.3, 'ECCS -

Shutdown,µ for emergency core cooling trains made inoperable by the containment sump.

2. Enter applicable Conditions and Required Actions of LCO 3.6.7,

'Recirculation Spray(RS),µ for recirculation spray trains made inoperable by the containment sump.

Restore the containment sump to OPERABLE status.

7 days C.

Required Action and associated Completion Time not met.

C.1 Be in MODE 3.

AND C.2 Be in MODE 5.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 36 hours ACTIONS (continued)

Serial No.24-031 Docket Nos:50-338/339, Page 6 of 7

Containment Sump 3.6.9 North Anna Units 1 and 2 3.6.9-3 Amendments SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.9.1 Verify, by visual inspection, the containment sump does not show structural damage, abnormal corrosion, or debris blockage.

In accordance with the Surveillance Frequency Control Program Serial No.24-031 Docket Nos: 50-338/339, Page 7 of 7

Serial No.: 24-031 Docket Nos.: 50-338/339 ATTACHMENT 3 Proposed Technical Specification Bases Changes (Mark-Ups)

For Information Only Virginia Electric and Power Company (Dominion Energy Virginia)

North Anna Power Station Unit 1 and Unit 2

North Anna Units 1 and 2 ii Revision 39 TECHNICAL SPECIFICATIONS BASES TABLE OF CONTENTS B 3.4 REACTOR COOLANT SYSTEM (RCS) (continued)

B 3.4.10 Pressurizer Safety Valves.............B 3.4.10-1 B 3.4.11 Pressurizer Power Operated Relief Valves (PORVs)....................B 3.4.11-1 B 3.4.12 Low Temperature Overpressure Protection (LTOP) System.................B 3.4.12-1 B 3.4.13 RCS Operational LEAKAGE..............B 3.4.13-1 B 3.4.14 RCS Pressure Isolation Valve (PIV) Leakage....B 3.4.14-1 B 3.4.15 RCS Leakage Detection Instrumentation.......B 3.4.15-1 B 3.4.16 RCS Specific Activity...............B 3.4.16-1 B 3.4.17 RCS Loop Isolation Valves.............B 3.4.17-1 B 3.4.18 RCS Isolated Loop Startup.............B 3.4.18-1 B 3.4.19 RCS Loops³Test Exceptions.............B 3.4.19-1 B 3.4.20 Steam Generator (SG) Tube Integrity........B 3.4.20-1 B 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS)......... B 3.5.1-1 B 3.5.1 Accumulators................... B 3.5.1-1 B 3.5.2 ECCS³Operating.................. B 3.5.2-1 B 3.5.3 ECCS³Shutdown................... B 3.5.3-1 B 3.5.4 Refueling Water Storage Tank (RWST)........ B 3.5.4-1 B 3.5.5 Seal Injection Flow................ B 3.5.5-1 B 3.5.6 Boron Injection Tank (BIT)............ B 3.5.6-1 B 3.6 CONTAINMENT SYSTEMS.................. B 3.6.1-1 B 3.6.1 Containment.................... B 3.6.1-1 B 3.6.2 Containment Air Locks............... B 3.6.2-1 B 3.6.3 Containment Isolation Valves........... B 3.6.3-1 B 3.6.4 Containment Pressure............... B 3.6.4-1 B 3.6.5 Containment Air Temperature............ B 3.6.5-1 B 3.6.6 Quench Spray (QS) System............. B 3.6.6-1 B 3.6.7 Recirculation Spray (RS) System.......... B 3.6.7-1 B 3.6.8 Chemical Addition System............. B 3.6.8-1 B 3.7 PLANT SYSTEMS..................... B 3.7.1-1 B 3.7.1 Main Steam Safety Valves (MSSVs)......... B 3.7.1-1 B 3.7.2 Main Steam Trip Valves (MSTVs).......... B 3.7.2-1 B 3.7.3 Main Feedwater Isolation Valves (MFIVs), Main Feedwater Pump Discharge Valves (MFPDVs),

Main Feedwater Regulating Valves (MFRVs),

and Main Feedwater Regulating Bypass Valves (MFRBVs)................ B 3.7.3-1 B 3.7.4 Steam Generator Power Operated Relief Valves (SG PORVs).................. B 3.7.4-1 B 3.7.5 Auxiliary Feedwater (AFW) System......... B 3.7.5-1 B 3.7.6 Emergency Condensate Storage Tank (ECST)..... B 3.7.6-1 B 3.7.7 Secondary Specific Activity............ B 3.7.7-1 B 3.7.8 Service Water (SW) System............. B 3.7.8-1 B 3.7.9 Ultimate Heat Sink (UHS)............. B 3.7.9-1 Serial No.24-031 Docket Nos: 50-338/339, Page 1 of 12 FOR INFORMATION ONLY

North Anna Units 1 and 2 B 3.5.2-1 Revision 0 ECCS³Operating B 3.5.2 B 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS)

B 3.5.2 ECCS³Operating BASES BACKGROUND The function of the ECCS is to provide core cooling and negative reactivity to ensure that the reactor core is protected after any of the following accidents:

a. Loss of coolant accident (LOCA), coolant leakage greater than the capability of the normal charging system;
b. Rupture of a control rod drive mechanism-control rod assembly ejection accident;
c. Loss of secondary coolant accident, including uncontrolled steam release or loss of feedwater; and
d. Steam generator tube rupture (SGTR).

The addition of negative reactivity is designed primarily for the MSLB where primary cooldown could add enough positive reactivity to achieve criticality and return to significant power.

There are three phases of ECCS operation: injection, cold leg recirculation, and hot leg recirculation. In the injection phase, water is taken from the refueling water storage tank (RWST) and injected into the Reactor Coolant System (RCS) through the cold legs. When sufficient water is removed from the RWST to ensure that enough boron has been added to maintain the reactor subcritical and the containment sumps have enough water to supply the required net positive suction head to the ECCS pumps, suction is switched to the containment sump for cold leg recirculation.

Within approximately 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />, the ECCS flow is shifted to the hot leg recirculation phase to provide a backflush, which would reduce the boiling in the top of the core and any resulting boron precipitation.

The ECCS consists of two separate subsystems: High Head Safety Injection (HHSI) and Low Head Safety Injection (LHSI). Each subsystem consists of two redundant, 100%

capacity trains. The ECCS accumulators and the RWST are also part of the ECCS, but are not considered part of an ECCS flow path as described by this LCO.

(continued)

Serial No.24-031 Docket Nos: 50-338/339, Page 2 of 12 FOR INFORMATION ONLY

ECCS³Operating B 3.5.2 BASES North Anna Units 1 and 2 B 3.5.2-3 Revision 0 BACKGROUND (continued)

The HHSI subsystem of the ECCS also functions to supply borated water to the reactor core following increased heat removal events, such as an MSLB. The limiting design conditions occur when the negative moderator temperature coefficient is highly negative, such as at the end of each cycle.

HHSI pumps A and B are capable of being automatically started and are powered from separate emergency buses. HHSI pump C can only be manually started, but can be powered from either of the emergency buses that HHSI pumps A and B are powered from. An interlock prevents HHSI pump C from being powered from both emergency buses simultaneously. For HHSI pump C to be OPERABLE, it must be running since it does not start automatically. In the event of a Safety Injection signal coincident with a loss of offsite power, interlocks prevent automatic operation of two HHSI pumps on the same emergency bus to prevent overloading the emergency diesel generators.

HHSI pump C is normally either running, or available but not running. HHSI pump C is normally running if either HHSI pump A or B is inoperable or both are otherwise preferred to not be in operation. HHSI pump C is normally available but not running when either HHSI pump A or B is running.

The ECCS subsystems are actuated upon receipt of an SI signal. The actuation of safeguard loads is accomplished in a programmed time sequence. If offsite power is available, the safeguard loads start immediately in the programmed sequence. If offsite power is not available, the Engineered Safety Feature (ESF) buses shed normal operating loads and are connected to the emergency diesel generators (EDGs).

Safeguard loads are then actuated in the programmed time sequence. The time delay associated with diesel starting and pump starting determines the time required before pumped flow is available to the core following a LOCA.

The active ECCS components, along with the passive accumulators and the RWST covered in LCO 3.5.1, "Accumulators," and LCO 3.5.4, "Refueling Water Storage Tank (RWST)," provide the cooling water necessary to meet Reference 1.

Serial No.24-031 Docket Nos: 50-338/339, Page 3 of 12 FOR INFORMATION ONLY

North Anna Units 1 and 2 B 3.5.2-10 Revision 46 ECCS³Operating B 3.5.2 BASES SURVEILLANCE REQUIREMENTS SR 3.5.2.4 (continued) which encompasses the ASME Code. The ASME Code provides the activities and Frequencies necessary to satisfy the requirements.

SR 3.5.2.5 and SR 3.5.2.6 These Surveillances demonstrate that each automatic ECCS valve actuates to the required position on an actual or simulated SI signal and that each ECCS pump capable of starting automatically starts on receipt of an actual or simulated SI signal. This Surveillance is not required for valves that are locked, sealed, or otherwise secured in the required position under administrative controls. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.5.2.7 Proper throttle valve position is necessary for proper ECCS performance and to prevent pump runout and subsequent component damage. The Surveillance verifies each listed ECCS throttle valve is secured in the correct position. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.5.2.8 Periodic inspections of the containment sump components ensure that they are unrestricted and stay in proper operating condition. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

Serial No.24-031 Docket Nos: 50-338/339, Page 4 of 12 FOR INFORMATION ONLY

North Anna Units 1 and 2 B 3.5.3-1 Revision 67 ECCS³Shutdown B 3.5.3 B 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS)

B 3.5.3 ECCS³Shutdown BASES BACKGROUND In MODE 4, ECCS is available to be manually started to provide water and negative reactivity to the reactor core, if needed. The required ECCS train consists of two separate subsystems: High Head Safety Injection (HHSI) and Low Head Safety Injection (LHSI).

The ECCS flow paths consist of piping, valves and pumps such that water from the refueling water storage tank (RWST) can be injected into the Reactor Coolant System (RCS). The accumulators and the RWST are also part of the ECCS, but are not considered part of an ECCS flow path as described by this LCO.

APPLICABLE SAFETY ANALYSES Based on the stable reactivity conditions and reduced core cooling requirements while in the Applicability, sufficient time exists for manual actuation of the required ECCS, if needed, and automatic initiation is not required.

Only one train of ECCS is required. This requirement dictates that single failures are not considered during this MODE of operation.

The ECCS-Shutdown satisfies Criterion 4 of 10 CFR 50.36(c)(2)(ii).

LCO In MODE 4, one ECCS train is required to be OPERABLE to ensure that ECCS flow is available to the core, if needed.

In MODE 4, an ECCS train consists of an HHSI subsystem and an LHSI subsystem. Each train includes the piping, instruments, and controls to ensure an OPERABLE flow path capable of (continued)

Serial No.24-031 Docket Nos: 50-338/339, Page 5 of 12 FOR INFORMATION ONLY

RS System B 3.6.7 BASES North Anna Units 1 and 2 B 3.6.7-9 Revision 73 SURVEILLANCE REQUIREMENTS (continued)

The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.6.7.5 Verifying that each RS and casing cooling pump's developed head at the flow test point is greater than or equal to the required developed head ensures that these pumps' performance has not degraded during the cycle. Flow and differential head are normal tests of centrifugal pump performance required by the ASME Code (Ref. 5). Since the RS System pumps cannot be tested with flow through the spray headers, they are tested on recirculation flow. This test confirms one point on the pump design curve and is indicative of overall performance. Such inservice tests confirm component OPERABILITY, trend performance, and detect incipient failures by indicating abnormal performance. The Frequency of this SR is in accordance with the Inservice Testing Program.

SR 3.6.7.6 These SRs ensure that each automatic valve actuates and that the casing cooling pumps start upon receipt of an actual or simulated High-High containment pressure signal. The RS pumps are verified to start with an actual or simulated RWST Level²Low signal coincident with a Containment Pressure²High High signal. The start delay times for the inside RS pumps are also verified. This Surveillance is not required for valves that are locked, sealed, or otherwise secured in the required position under administrative controls. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

SR 3.6.7.7 Periodic inspections of the containment sump components ensure that they are unrestricted and stay in proper operating condition. The Surveillance Frequency is based on operating experience, equipment reliability, and plant risk and is controlled under the Surveillance Frequency Control Program.

(continued)

Serial No.24-031 Docket Nos: 50-338/339, Page 6 of 12 FOR INFORMATION ONLY

North Anna Units 1 and 2 B 3.6.7-10 Revision 73 RS System B 3.6.7 BASES SURVEILLANCE REQUIREMENTS (continued)

SR 3.6.7.8 This SR ensures that each spray nozzle is unobstructed and that spray coverage of the containment will meet its design bases objective. Either an inspection of the nozzles or an air or smoke test is performed through each spray header. Due to the passive design of the spray header and its normally dry state, a test performed following maintenance which could result in nozzle blockage is considered adequate for detecting obstruction of the nozzles.

REFERENCES

1. UFSAR, Section 6.2.
2. 10 CFR 50.49.
3. 10 CFR 50.46.
4. UFSAR, Section 15.4.1.7.
5. ASME Code for Operation and Maintenance of Nuclear Power Plants.

Serial No.24-031 Docket Nos: 50-338/339, Page 7 of 12 FOR INFORMATION ONLY

B 3.6 CONTAINMENT SYSTEMS B 3.6.9 Containment Sump BASES BACKGROUND The containment sump provides a borated water source to support recirculation of coolant from the containment sump for residual heat removal, emergency core cooling, containment cooling, and containment atmosphere cleanup during accident conditions.

The containment sump supplies both trains of the Emergency Core Cooling System (ECCS) and Recirculation Spray (RS) System during any accident that requires recirculation of coolant from the containment sump.

The recirculation mode is initiated when the pump suction is transferred to the containment sump on low Refueling Water Storage Tank (RWST) level, which ensures the containment sump has enough water to supply the net positive suction head to the ECCS and RS System pumps. The use of a single containment sump to supply both trains of the ECCS and RS System is acceptable since the containment sump is a passive component, and passive failures are not required to be assumed to occur coincident with Design Basis Events.

The containment sump contains strainers to limit the quantity of the debris materials from entering the sump suction piping. Debris accumulation on the strainers can lead to undesirable hydraulic effects including air ingestion through vortexing or deaeration, and reduced net positive suction head (NPSH) at pump suction piping.

While the majority of debris accumulates on the strainers, some fraction penetrates the strainers and is transported to downstream components in the ECCS, RS System, and the Reactor Coolant System (RCS). Debris that penetrates the strainer can result in wear to the downstream components, blockages, or reduced heat transfer across the fuel cladding. Excessive debris in the containment sump water source could result in insufficient recirculation of coolant during the accident, or insufficient heat removal from the core during the accident.

APPLICABLE During all accidents that require recirculation, the containment sump SAFETY provides a source of borated water to the ECCS and RS System ANALYSIS pumps. As such, it supports residual heat removal, emergency core cooling, containment cooling, and containment atmosphere cleanup during an accident. It also provides a source of negative reactivity (Ref. 1). The design basis transients and applicable safety analyses concerning each of these systems are discussed in the Applicable Safety Analyses section of B 3.5.2, "ECCS - Operating," B 3.5.3, "ECCS -

Shutdown," and B 3.6.7, "Recirculation Spray (RS) System."

Serial No.24-031 Docket Nos: 50-338/339, Page 8 of 12 FOR INFORMATION ONLY

BASES APPLICABLE FSAR Section 6.2.2 (Ref. 2) describes evaluations that confirm long-term SAFETY ANALYSIS core cooling is assured following any accident that requires recirculation (continued) from the containment sump.

The containment sump satisfies Criterion 3 of 10 CFR 50.36(c)(2)(ii).

LCO The containment sump is required to ensure a source of borated water to support ECCS and RS System OPERABILITY. A containment sump consists of the containment drainage flow paths, the containment sump strainers, and the inlet to the ECCS and RS System piping. An OPERABLE containment sump has no structural damage or abnormal corrosion that could prevent recirculation of coolant and will not be restricted by containment accident generated and transported debris.

Containment accident generated and transported debris consists of the following:

a.

Accident generated debris sources - Insulation, coatings, and other materials which are damaged by the high-energy line break (HELB) and transported to the containment sump. This includes materials within the HELB zone of influence and other materials (e.g.,

unqualified coatings) that fail due to the post-accident containment environment following the accident; b.

Latent debris sources - Pre-existing dirt, dust, paint chips, fines or shards of insulation, and other materials inside containment that do not have to be damaged by the HELB to be transported to the containment sump; and c.

Chemical product debris sources - Aluminum, zinc, carbon steel, copper, and non-metallic materials such as paints, thermal insulation, and concrete that are susceptible to chemical reactions within the post-accident containment environment leading to corrosion products that are generated within the containment sump pool or are generated within containment and transported to the containment sump.

Containment debris limits are defined in calculation ME-780 (Ref. 3).

APPLICABILITY In MODES 1, 2, 3, and 4, containment sump OPERABILITY requirements are dictated by the ECCS and RS System OPERABILITY requirements.

Since both the ECCS and the RS System must be OPERABLE in MODES 1, 2, 3, and 4, the containment sump must also be OPERABLE to support their operation.

In MODES 5 and 6, the probability and consequences of these events are reduced due to the pressure and temperature limitations of these MODES. Thus, the containment sump is not required to be OPERABLE in MODES 5 or 6.

Serial No.24-031 Docket Nos: 50-338/339, Page 9 of 12 FOR INFORMATION ONLY

BASES ACTIONS A.1, A.2, and A.3 Condition A is applicable when there is a condition which results in containment accident generated and transported debris exceeding the analyzed limits. Containment debris limits are defined calculation ME-780 (Ref. 3).

Immediate action must be initiated to mitigate the condition. Examples of mitigating actions are:

Removing the debris source from containment or preventing the debris from being transported to the containment sump; Evaluating the debris source against the assumptions in the analysis; Deferring maintenance that would affect availability of the affected systems and other LOCA mitigating equipment; Deferring maintenance that would affect availability of primary defense-in-depth systems, such as containment coolers; Briefing operators on LOCA debris management actions; or Applying an alternative method to establish new limits.

While in this condition, the RCS water inventory balance, SR 3.4.13.1, must be performed at an increased Frequency of once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. An unexpected increase in RCS leakage could be indicative of an increased potential for an RCS pipe break, which could result in debris being generated and transported to the containment sump. The more frequent monitoring allows operators to act in a timely fashion to minimize the potential for an RCS pipe break while the containment sump is inoperable.

The inoperable containment sump must be restored to OPERABLE status in 90 days. A 90-day Completion Time is reasonable for emergent conditions that involve debris in excess of the analyzed limits that could be generated and transported to the containment sump under accident conditions. The likelihood of an initiating event in the 90-day Completion Time is very small and there is margin in the associated analyses. The mitigating actions of Required Action A.1 provide additional assurance that the effects of debris in excess of the analyzed limits will be mitigated during the Completion Time.

Serial No.24-031 Docket Nos: 50-338/339, Page 10 of 12 FOR INFORMATION ONLY

BASES ACTIONS (continued)

B.1 When the containment sump is inoperable for reasons other than Condition A, such as blockage, structural damage, or abnormal corrosion that could prevent recirculation of coolant, it must be restored to OPERABLE status within 7 days. The 7 day Completion Time takes into account the reasonable time for repairs, and low probability of an accident that requires the containment sump occurring during this period.

Required Action B.1 is modified by two Notes. The first Note indicates that the applicable Conditions and Required Actions of LCO 3.5.2, "ECCS

- Operating," and LCO 3.5.3, "ECCS - Shutdown," should be entered if an inoperable containment sump results in an inoperable ECCS train. The second Note indicates that the applicable Conditions and Required Actions of LCO 3.6.7, Recirculation Spray (RS) System," should be entered if an inoperable containment sump results in an inoperable RS System train. This is an exception to LCO 3.0.6 and ensures the proper actions are taken for these components.

C.1 and C.2 If the containment sump cannot be restored to OPERABLE status within the associated Completion Time, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to 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 to MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

Serial No.24-031 Docket Nos: 50-338/339, Page 11 of 12 FOR INFORMATION ONLY

BASES SURVEILLANCE SR 3.6.9.1 REQUIREMENTS Periodic inspections are performed to verify the containment sump does not show current or potential debris blockage, structural damage, or abnormal corrosion to ensure the operability and structural integrity of the containment sump (Ref. 1).

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

REFERENCES

1. FSAR, Chapter 6 and Chapter 15.

2.

FSAR, Section 6.2.2, Containment Heat Removal Systems -

Containment Depressurization System.

3.

NA-CALC-MEC-ME-0780, Post LOCA Debris Transport to Containment Sump Strainer for Resolution of GSI-191 Serial No.24-031 Docket Nos: 50-338/339, Page 12 of 12 FOR INFORMATION ONLY

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