ML23326A136

Safety Evaluation for Amendment 195 & 192 for TS 3.1.9 More Restrictive Action

ML23326A136
Person / Time
Site:	Vogtle
Issue date:	11/28/2023
From:	Gleaves W NRC/NRR/VPOB
To:	Coleman J City of Dalton, GA, Georgia Power Co, MEAG Power, Oglethorpe Power Corp, Southern Nuclear Operating Co
Shared Package
ML23326A154	List: ML23289A163 ML23326A136
References
EPID L-2023-LLA-0072
Download: ML23326A136 (15)

Text

Enclosure 3 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 195 TO COMBINED LICENSE NO. NPF-91 AND AMENDMENT NO. 192 TO COMBINED LICENSE NO. NPF-92 SOUTHERN NUCLEAR OPERATING COMPANY, INC.

GEORGIA POWER COMPANY OGLETHORPE POWER CORPORATION MEAG POWER SPVM, LLC MEAG POWER SPVJ, LLC MEAG POWER SPVP, LLC CITY OF DALTON, GEORGIA VOGTLE ELECTRIC GENERATING PLANT, UNITS 3 AND 4 DOCKET NOS.52-025 AND 52-026

1.0 INTRODUCTION

By letter dated May 17, 2023 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML23137A285), Southern Nuclear Operating Company (SNC, the licensee) submitted a license amendment request (LAR) proposing changes to the Technical Specifications for the Vogtle Electric Generating Plant (Vogtle), Units 3 and 4, Combined License (COL) Numbers NPF-91 and NPF-92, respectively. The Nuclear Regulatory Commission (NRC or the Commission) staff accepted this LAR for review on June 5, 2023 (ML23156A464).

2.0 REGULATORY EVALUATION

The staff considered the following regulatory requirements in reviewing the LAR:

Title 10 of the Code of Federal Regulations (10 CFR) 10 CFR 52.98(f) provides that any modification to, addition to, or deletion from the terms and conditions of a COL is a proposed license amendment. These activities involve a change to COL, Appendix A, technical specification (TS) information; therefore, a license amendment is required prior to making these plant-specific proposed changes.

Regulation in 10 CFR Part 52, Appendix D, VIII.C.6, states that after issuance of a license, Changes to the plant-specific TS will be treated as license amendments under 10 CFR 50.90.

Regulations in 10 CFR 50.90 address the application for amendment of a license, including a combined license. The licensee is requesting changes in the TSs; therefore, a LAR is required to be submitted for NRC approval.

In 10 CFR 50.36, the Commission established its regulatory requirements related to the content of TSs. Pursuant to 10 CFR 50.36, TSs are required to include items in the following five specific categories related to station operation: (1) safety limits, limiting safety system settings, and limiting control settings; (2) limiting conditions for operation (LCO); (3) surveillance requirements (SR); (4) design features; and (5) administrative controls. The regulation also states, in part, that [a] summary statement of the bases or reasons for such specifications, other than those covering administrative controls, shall also be included in the application, but shall not become part of the technical specifications.

Regulation in 10 CFR 50.36(b) states that TSs will be derived from the analyses and evaluation included in the safety analysis report, and amendments thereto, submitted pursuant to § 50.34.

The categories of items required to be in the TSs are provided in 10 CFR 50.36(c). As required by 10 CFR 50.36(c)(2)(i), the TSs will include LCOs, which are the lowest functional capability or performance levels of equipment required for safe operation of the facility. The regulation at 10 CFR 50.36(c)(2)(i) requires that when an LCO of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the TSs until the condition can be met. These remedial actions are referred to as Required Actions in the TSs.

10 CFR 50.92(a) states when determining whether to issue a license amendment, the Commission will be guided by the considerations which govern the issuance of initial licenses to the extent applicable and appropriate. In determining whether the proposed TS remedial actions should be granted, the NRC staff typically applies the reasonable assurance standard derived from the requirements of 10 CFR 50.40(a) and 50.57(a)(3). The regulation at 10 CFR 50.40(a) states that in determining whether to grant the licensing request, the Commission will be guided by, among other things, consideration about whether the processes to be performed, the operating procedures, the facility and equipment, the use of the facility, and other technical specifications, or the proposals, in regard to any of the foregoing collectively provide reasonable assurance that the applicant will comply with the regulations in this chapter, including the regulations in Part 20 of this chapter, and that the health and safety of the public will not be endangered. The regulation at 10 CFR 50.57(a)(3) states that the Commission may issue an operating license when, in part, there is reasonable assurance that the activities authorized by the operating license can be conducted without endangering the health and safety of the public.

The TS 1.3, Completion Times establishes the Completion Time convention and provides guidance for its use through several examples. While the TS 1.3 examples are not regulations, they constitute license requirements imposed on plant operation by informing the implementation of the TS usage rules.

3.0 TECHNICAL EVALUATION

The LAR proposed changes to TS 3.1.9, Chemical and Volume Control System (CVS)

Demineralized Water Isolation Valves and Makeup Line Isolation Valves. The CVS is designed to (1) make up for minor leakage from the reactor coolant system; (2) make up for thermal expansion during heatup from cold shutdown; (3) let down from contraction during cooldown; (4) support the water chemistry and chemical shim requirements of the reactor coolant system; and (5) meet TS requirements for isolation. This inventory and chemistry control is provided by letdown and makeup connections to the CVS purification loop.

The safety related purpose of the demineralized water isolation valves and the makeup line isolation valves in the CVS is to provide isolation as necessary to support the reactor coolant system inventory and chemistry. The safety related functions provided by the CVS include containment isolation of CVS lines penetrating containment, termination of inadvertent boron dilution, and preservation of the reactor coolant system (RCS) pressure boundary, including isolation of CVS letdown from the RCS. The CVS demineralized water isolation valves function to isolate to prevent an inadvertent boron dilution event. Another of the safety related functions provided by the CVS is the termination of RCS makeup to prevent overfilling of the pressurizer during non-loss of coolant accident (non-LOCA) transients or to prevent the steam generator from overfilling during a steam generator tube rupture. The CVS makeup line isolation valves provide this RCS makeup isolation function.

2.1 DESCRIPTION

OF REQUESTED CHANGES The LAR proposed changes to TS 3.1.9, Chemical and Volume Control System (CVS)

Demineralized Water Isolation Valves and Makeup Line Isolation Valves. The licensees proposed changes include a new NOTE to the ACTIONS table allowing separate Condition entry. The proposed changes also include deletion of the third Condition description in Condition A and revisions to Required Actions A.1 and B.1. The proposed changes to Condition A and Required Actions A.1 align those portions of the ACTIONS table with the allowance of a separate Condition entry. The deletion/revision to Required Action B.1 expands the Required Action to encompass any valve that would be in a flow path to the RCS as described in Condition B. The licensee stated the NOTE allowing separate Condition entry and the changes to Condition A would avoid unnecessary entries into LCO 3.0.3. The licensee stated that the changes to Required Action B.1 would address an existing non-conservative action.

The licensee did not propose changes to the LCO and APPLICABILITY statement for TS 3.1.9.

The current LCO states: Two CVS Demineralized Water Isolation Valves and two CVS Makeup Line Isolation Valves shall be OPERABLE. The APPLICABILITY for TS 3.1.9 is stated as:

MODES 1, 2, 3, 4, and 5. To illustrate the proposed changes, the text of the licensees proposed additions is double underlined, and the text of the proposed deletions appears in strikethrough text below.

ACTIONS

- NOTES -

1.

Flow path(s) may be unisolated intermittently under administrative controls.

2.

Separate Condition entry is allowed for each valve.

CONDITION REQUIRED ACTION COMPLETION TIME A.

One CVS demineralized water isolation valve inoperable.

A.1 Restore two CVS demineralized water isolation valves and two CVS makeup line isolation valves to OPERABLE status.

72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> OR One CVS makeup line isolation valve inoperable.

OR One CVS demineralized water isolation valve and one CVS makeup line isolation valve inoperable B. Required Action and associated Completion Time of Condition A not met.

OR Two CVS demineralized water isolation valves inoperable.

OR Two CVS makeup line isolation valves inoperable.

B.1 Isolate the affected flow path(s) from the demineralized water storage tank to the Reactor Coolant System by use of at least one closed manual or one closed and de-activated automatic valve.

1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> 3.2 EVALUATION OF THE REQUESTED CHANGES The staff reviewed the current TS 3.1.9 requirements, the proposed changes, and the licensees evaluation of the proposed changes to determine if the regulatory requirements for TSs would be met by the proposed changes.

The LCO 3.1.9 requirement that at least two CVS demineralized water isolation valves and two CVS makeup line isolation valves be OPERABLE assures that: (1) there will be redundant means available to terminate or prevent an inadvertent boron dilution event; and (2) there will be redundant means available to terminate CVS makeup to the RCS during a non-LOCA event or steam generator tube rupture accident, should that become necessary to provide protection from overfilling the pressurizer or steam generator.

In sections 2.3 and 3.2 of the LAR, the licensee provided the reason for and evaluated the changes to TS 3.1.9 to add an allowance for separate Condition entry. In sections 2.3 and 3.3 of the LAR, the licensee provided the reason for and evaluated the changes to TS 3.1.9 to address the non-conservative aspect of TS 3.1.9.

3.2.1 CORRECTION OF NON-CONSERVATIVE TECHNICAL SPECIFICATION The licensee also explained that current Required Action B.1 was non-conservative, stating:

TS 3.1.9 Action B requirement to isolate from the demineralized water storage tank to the Reactor Coolant System reflects a non-conservative TS action in that it only protects the boron dilution mitigation safety function for the CVS demineralized water isolation valves, and does not require protecting the boron dilution mitigation and pressurizer overfill safety functions for the CVS makeup line isolation valves, since the makeup line flow path is not specifically isolated if the isolation is made at the demineralized water storage tank. Therefore, to address the non-conservative action, VEGP has imposed a more restrictive administrative requirement in accordance with the guidance in NRC Administrative Letter (AL) 98-10, Dispositioning of Technical Specifications That Are Insufficient to Assure Plant Safety. For inoperabilities of CVS makeup isolation valves, isolating the affected flow path must prevent flow from the CVS makeup pumps to the RCS in order to provide protection from overfilling. Isolation can be accomplished by manually closing the CVS makeup isolation MOVs [motor-operated valves] or alternatively, manual valve(s) in the makeup line between the makeup pumps and the RCS.

In Section 3.3 of the LAR, the licensee stated, in part:

The proposed change to eliminate from the demineralized water storage tank, leaving the broader requirement for isolating the affected flow path(s) to the RCS, imposes a more restrictive action for the MODE 5 application to the CVS makeup line isolation valves. To meet the proposed Required Action B.1 for inoperable CVS makeup isolation valves, the affected flow path to the RCS would provide the required protection to preclude make up flow that could challenge boron dilution and/or pressurizer overfill, thereby protecting the safety function(s).

The staff reviewed the licensees explanation and determined that the current Required Action B.1 is non-conservative because it does not address all of the CVS safety functions (i.e., it does not require isolation of the makeup line flow path to the RCS, which could be a source of water during a boron dilution or pressurizer overfill event). To address this issue, the licensee proposed to remove from the demineralized water storage tank from the Required Action. The staff determined that the proposed change to the Required Actions would ensure that appropriate remedial actions would be required in Condition B. The staff further determined that the Required Actions meet the regulatory requirement in 10 CFR 50.36(c)(2)(i) for remedial actions permitted while the LCO is not met. Therefore, this change is acceptable.

3.2.2 SEPARATE CONDITION ENTRY In Section 2.3 of the LAR the licensee explained the reason for the proposed allowance for separate condition entry and stated:

TS 3.1.9 Actions do not include an allowance for separate Condition entry for each inoperable valve, which is typical for TS that address multiple valves and have an Action provision to isolate the affected flow path and continue operations (e.g., TS 3.6.3, Containment Isolation Valves). As such, if demineralized water isolation valve inoperability has had its flow path isolated to meet Required Action B.1, a subsequent makeup line isolation valve inoperability requiring flow path isolation in accordance with Required Action B.1 would not be allowed a separate Completion Time to complete the isolation, which would require an undesired entry into LCO 3.0.3. By including an Actions Note providing Separate Condition entry is allowed for each inoperable valve would avoid the unnecessary LCO 3.0.3 entry. That Actions Note would also allow clarification to Condition A by eliminating the third Condition for the combination of both one CVS demineralized water isolation valve and one CVS makeup line isolation valve inoperable.

The current TS LCO 3.0.3 requires that when an LCO is not met and the associated ACTIONS are not met, an associated ACTION is not provided, or if directed by the associated ACTIONS, the unit shall be placed in a MODE or other specified condition in which the LCO is not applicable. LCO 3.0.3 also provides the specific times in which the unit must be placed into the other MODE. The licensee justified the separate condition entry allowance in Section 3.2 of the LAR, stating that rather than the current requirement of an LCO 3.0.3 entry for the situation where, after entering Condition B, one or both valves of the other type is determined to be inoperable, the proposed change would allow 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to address the second valve inoperability, which is the existing Completion Time for Required Action B.1. The staff agrees with the licensees justification for the separate Completion Time allowance to continue plant operation during these types of situations because, by isolating the affected flow path(s) within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, systems and components are placed in the assumed post - accident position.

The licensee also cited TS Section 1.3, Example 1.3-5, to support the proposed change. The explanation for TS 1.3, Example 1.3-5, on TS page 1.3-8 states:

The Note above the ACTIONS Table is a method of modifying how the Completion Time is tracked. If this method of modifying how the Completion Time is tracked was only applicable to a specific Condition, the Note would appear in that Condition rather than at the top of the ACTIONS Table.

The Note allows Condition A to be entered separately for each inoperable valve, and Completion Times tracked on a per valve basis. When a valve is declared inoperable, Condition A is entered, and its Completion Time starts. If subsequent valves are declared inoperable, Condition A is entered for each valve and separate Completion Times start and are tracked for each valve.

If the Completion Time associated with a valve in Condition A expires, Condition B is entered for that valve. If the Completion Times associated with subsequent valves in Condition A expire, Condition B is entered separately for each valve and separate Completion Times start and are tracked for each valve.

If a valve which caused entry into Condition B is restored to OPERABLE status, Condition B is exited for that valve. Since the Note in this example allows multiple Condition entry and tracking of separate Completion Times, Completion Time extensions do not apply.

The staff determined the cited example aligns with the licensees justification for the proposed change and that example 1.3-5 states that Completion Time extensions do not apply. The staff noted the proposed revisions to Required Action A.1 would appropriately reflect the allowance for separate condition entry.

The staff reviewed SNCs basis for allowing separate condition entry for the CVS demineralized water isolation valves and makeup line isolation valves. The staff noted that, SNCs explanation of avoiding LCO 3.0.3 entry notwithstanding, in general, the rationale for allowing separate Condition entry in TSs is that the Required Actions provide appropriate compensatory actions for each inoperable component. Complying with the Required Actions may allow for continued operation, and subsequent inoperable components are governed by subsequent Condition entries and application of associated Required Actions. The staff reviewed the proposed changes to the ACTIONS table. The staff determined that the Required Actions for Condition A and Condition B would provide appropriate compensatory actions for each inoperable valve, continued operation would be allowed after timely completion of Required Actions for each valve, and subsequent inoperable valves would be governed by subsequent Condition entry and application of associated Required Actions. The staff further determined that the Required Actions meet the regulatory requirement in 10 CFR 50.36(c)(2)(i) for remedial actions permitted while the LCO is not met. Therefore, this change is acceptable.

3.3

SUMMARY

The staff reviewed the information provided in Section 2.3 and 3.2 of the LAR, and based on the evaluation above, determined that the TS, as amended by the proposed allowance for separate condition entry, along with associated changes to the description of Condition A, will continue to require appropriate remedial measures when the LCO is not met and will address the non-conservative TS.

The staff determined that the TS, as amended, will continue to meet the regulatory requirements of 10 CFR 50.36(b) because the TS will continue to be derived from the analyses and evaluation included in the safety analysis report, and amendments thereto, submitted pursuant to § 50.34. The staff also determined that the regulatory requirements of 10 CFR 50.36(c)(2)(i) will continue to be met because the TS, as amended by the proposed changes, will continue to require the licensee to shut down the reactor or follow permitted remedial measures when the LCO is not met. The NRC staff finds that the required actions as revised remain acceptable since the licensee has demonstrated, through evaluations and analyses presented in the LAR, that there is reasonable assurance of adequate protection of the public health and safety.

Therefore, the staff determined the changes are acceptable.

4.0 STATE CONSULTATION

In accordance with the Commissions regulations in 10 CFR 50.91(b), the Georgia State official was notified of the proposed issuance of the amendment. In accordance with the Commissions regulations in 10 CFR 50.91(b), on October 16, 2023, the Commission consulted the State official. The State of Georgia had no comment.

5.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding Federal Register (88 FR 44162) July 11, 2023. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.

6.0 CONCLUSION

The Commission has concluded, based on the considerations discussed above that:

(1) there is reasonable assurance that the health and safety of the public will not be endangered by the operation in the proposed manner, (2) there is reasonable assurance that 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. Therefore, the staff finds the changes proposed in this license amendment acceptable.

REFERENCES

1.

Southern Nuclear Operating Company, Vogtle Electric Generating Plant, Units 3 and 4, More Restrictive Action for Technical Specification 3.1.9 (LAR-23-006R1), May 17, 2023 (ML23137A285).

2.

Southern Nuclear Operating Company, Vogtle Electric Generating Plant, Units 3 and 4, Acceptance of LAR 23-006, Rev. 1, More Restrictive Action for Technical Specification 3.1.9, June 5, 2023 (ML23156A464).

3.

Combined License NPF-91 for Vogtle Electric Generating Plant, Unit 3, Appendix A, Vogtle Electric Generating Plant Units 3 and 4 Technical Specifications, Southern Nuclear Operating Company, February 10, 2012 (ML14100A106).

4.

Combined License NPF-92 for Vogtle Electric Generating Plant, Unit 4, Appendix A, Vogtle Electric Generating Plant Units 3 and 4 Technical Specifications, Southern Nuclear Operating Company, February 10, 2012 (ML14100A135).

5.

Vogtle Electric Generating Plant Units 3 and 4, Updated Final Safety Analysis Report, Revision 12, June 13, 2023 (ML23165A228).

Principal Contributor: M. Hamm, NRR Date: November 28, 2023