Text

License Amendment Request to Increase Flexibility in Mode Restraints
	ML24354A169
Person / Time
Site:	Vogtle
Issue date:	12/19/2024
From:	Coleman J; Southern Nuclear Operating Co
To:	; Office of Nuclear Reactor Regulation, Document Control Desk
References
	NL-24-0412
	Download: ML24354A169 (1)
	v • d • e

A Southern Nuclear December 19, 2024 Docket Nos.: 52-025 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 Units 3 and 4 3535 Colonnade Parkway Birmingham, AL 35243 Tel. 205.992.5000 NL-24-0412 10 CFR 50.90 License Amendment Request to Increase Flexibility in Mode Restraints Ladies and Gentlemen:

Pursuant to 10 CFR 52.98(c) and in accordance with 10 CFR 50.90, Southern Nuclear Operating Company (SNC) requests an amendment to the combined licenses (COLs) for Vogtle Electric Generating Plant (VEGP) Unit 3 (License No. NPF-91) and Unit 4 (License No.

NPF-92). The license amendment request (LAR) proposes changes to the COLs' Appendix A, Technical Specifications (TS), to increase flexibility in mode restraints.

The proposed changes are similar to those described in Technical Specification Task Force (TSTF) 359, Revision 9, "Increased Flexibility in Mode Restraints," with enhancements similar to those identified in TSTF-529, Revision 4, "Clarify Use and Application Rules," for Limiting Condition for Operation (LCO) 3.0.4.

These changes were previously discussed with the NRC Staff during a public conference call on October 16, 2024 (see ADAMS Accession Numbers ML24283A202 and ML24292A002). SNC has incorporated information into the request to address topics discussed during the above call.

The Enclosure provides the description, technical evaluation, regulatory evaluation (including the Significant Hazards Consideration Determination) and environmental considerations for the proposed changes.

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

SNC requests approval of the proposed LAR no later than twelve months from acceptance.

SNC expects to implement the proposed amendment within 90 days of issuance.

In accordance with 10 CFR 50.91, a copy of this application, with enclosures, is being provided to the designated State of Georgia official.

U. S. Nuclear Regulatory Commission NL-24-0412 Page 2 If you have any questions, please contact Mr. Ryan Joyce at (205) 992-6468.

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

Executed on the 19th day of December 2024.

Respectfully submitted, Jamie M. Coleman Regulatory Affairs Director

Enclosure:

Evaluation of Proposed Changes 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

ENCLOSURE to NL-24-0412 Evaluation of Proposed Changes License Amendment Request to Increase Flexibility in Mode Restraints 1.0

SUMMARY

DESCRIPTION 2.0 DETAILED DESCRIPTION 2.1. Background Information 2.2. Current Requirements 2.3. Reason for the Proposed Changes 2.4. Description of the Proposed Changes

3.0 TECHNICAL EVALUATION

4.0 REGULATORY EVALUATION

4.1. Applicable Regulatory Requirements/Criteria 4.2. Precedent 4.3. Significant Hazards Consideration 4.4. Conclusions

5.0 ENVIRONMENTAL CONSIDERATION

6.0 REFERENCES

Attachments 1. Proposed Technical Specification Changes (Mark-ups)

2. Clean Revised Technical Specification Pages

3. Associated Technical Specification Bases Changes (for information only)

4. Assessment for Precluding Use of LCO 3.0.4.b

Enclosure to NL-24-0412 Evaluation of Proposed Changes 1.0

SUMMARY

DESCRIPTION Southern Nuclear Operating Company (SNC) requests an amendment to the Combined License (COL) for Vogtle Electric Generating Plant (VEGP), Units 3 and 4 (License Nos. NPF-91 and NPF-92, respectively). The proposed amendment would revise Appendix A, Technical Specifications (TS), of the COL to increase flexibility in mode restraints. The proposed changes adopt concepts similar to those that are described in Technical Specification Task Force (TSTF) 359, Revision 9, "Increased Flexibility in Mode Restraints," with enhancements similar to those identified in TSTF-529, Revision 4, "Clarify Use and Application Rules," for Limiting Condition for Operation (LCO) 3.0.4.

2.0 DETAILED DESCRIPTION 2.1 Background Information The proposed changes revise TS requirements for mode change limitations in LCO 3.0.4 and Surveillance Requirement (SR) 3.0.4 similar to the changes that are described in TSTF-359, Revision 9 (TSTF-359), "Increase Flexibility in Mode Restraints" (Reference 1 ). The availability of TSTF-359 was announced in the Federal Register on April 4, 2003 (68 FR 16579) as part of the Consolidated Line-Item Improvement Process (CLIIP), which included a Model Safety Evaluation (SE). TSTF-359 was one of the industry's initiatives implemented under the risk-informed TS program. These initiatives were intended to maintain or improve safety while reducing unnecessary burden and to make TS requirements consistent with the other U.S.

Nuclear Regulatory Commission (NRC) risk-informed regulatory requirements, in particular, the Maintenance Rule.

By letter dated February 29, 2016, TSTF-529, Revision 4 (TSTF-529), "Clarify Use and Application Rules," was transmitted to the NRC and proposed changes to clarify and expand the use and application of the Standard TS usage rules. TSTF-529 proposed enhancements to LCO 3.0.4 and SR 3.0.3, among other changes (Reference 2). The NRC issued its Final SE of TSTF-529 on April 21, 2016 (Reference 3). On April 26, 2023, the NRC issued Amendment Nos. 191 and 188 to COL Nos. NPF-91 and NPF-92 for the VEGP, Units 3 and 4 (VEGP 3&4),

respectively, which authorized changes to SR 3.0.3 consistent with TSTF-529. This is relevant since LCO 3.0.4 enhancements were included in the same traveler, but they were not adopted as part of Amendment Nos. 191 and 188.

For this license amendment request, SNC is proposing changes reflecting the LCO 3.0.4 topic from the NRC approved changes identified in TSTF-529, "Clarify Use and Application Rules";

and associated Bases changes. The remaining topics in TSTF-529 are under review for further changes to the licensing basis.

In summary, this license amendment request (LAR) proposes a change to the VEGP 3&4 TS to increase flexibility in mode restraints, similar to the concepts described in TSTF-359. The proposed changes also include minor enhancements to LCO 3.0.4, which were included as part of TSTF-529.

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Enclosure to NL-24-0412 Evaluation of Proposed Changes 2.2 Current Requirements Appendix A of the VEGP 3&4 COL establishes general requirements in Section 3.0 that are applicable to all Specifications and apply at all times, unless otherwise stated. Included in these general requirements is LCO 3.0.4, which establishes limitations on changes in MODES or other specified conditions in the Applicability when an LCO is not met. It precludes placing the unit in a MODE or other specified condition stated in that Applicability (e.g., Applicability desired to be entered) when the following exist:

a. Unit conditions are such that the requirements of the LCO would not be met in the Applicability desired to be entered; and

b. Continued noncompliance with the LCO requirements, if the Applicability were entered, would result in the unit being required to exit the Applicability desired to be entered to comply with the Required Actions.

LCO 3.0.4 states:

When an LCO is not met, entry into a MODE or other specified condition in the Applicability shall not be made except when the associated ACTIONS to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time. This Specification shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or are part of a shutdown of the unit.

Exceptions to this Specification are stated in the individual Specifications.

LCO 3.0.4 is only applicable for entry into a MODE or other specified condition in the Applicability in MODES 1, 2, 3, and 4.

Compliance with Required Actions that permit continued operation of the unit for an unlimited period of time in a MODE or other specified condition provides an acceptable level of safety for continued operation. This is without regard to the status of the unit before or after the MODE change. Therefore, in such cases, entry into a MODE or other specified condition in the Applicability may be made in accordance with the provisions of the Required Actions.

There are exceptions to LCO 3.0.4, which are stated in the individual Specifications. These exceptions allow entry into MODES or other specified conditions in the Applicability when the associated ACTIONS to be entered do not provide for continued operation for an unlimited period of time. Exceptions may apply to all the ACTIONS or to a specific Required Action of a Specification. The following VEGP 3&4 Specifications currently include an exception to LCO 3.0.4:

TS 3.3.17 - Post Accident Monitoring (PAM) Instrumentation TS 3.3.18 - Remote Shutdown Workstation (RSW)

TS 3.4.9 - Reactor Coolant System (RCS) Leakage Detection Instrumentation TS 3.4.10 - RCS Specific Activity E-3

Enclosure to NL-24-0412 Evaluation of Proposed Changes LCO 3.0.4 is applicable when entering MODE 4 from MODE 5, MODE 3 from MODE 4 or 5, MODE 2 from MODE 3 or 4 or 5, or MODE 1 from MODE 2. Furthermore, LCO 3.0.4 is applicable when entering any other specified condition in the Applicability only while operating in MODE 1, 2, 3, or 4. The requirements of LCO 3.0.4 do not apply in MODES 5 and 6, or in other specified conditions of the Applicability (unless in MODE 1, 2, 3, or 4) because the ACTIONS of individual Specifications sufficiently define the remedial measures to be taken.

Surveillances do not have to be performed on the associated inoperable equipment (or on variables outside the specified limits), as permitted by SR 3.0.1. Therefore, changing MODES or other specified conditions while in an ACTIONS Condition, in compliance with LCO 3.0.4 or where an exception to LCO 3.0.4 is stated, is not a violation of SR 3.0.1 or SR 3.0.4 for those Surveillances that do not have to be performed due to the associated inoperable equipment.

However, SRs must be met to ensure OPERABILITY prior to declaring the associated equipment OPERABLE (or variable within limits) and restoring compliance with the affected LCO.

SR 3.0.4 is also a general requirement of the TS and establishes that all applicable SRs must be met before entry into a MODE or other specified condition in the Applicability. This Specification ensures that system and component OPERABILITY requirements and variable limits are met before entry into MODES or other specified conditions in the Applicability for which these systems and components ensure safe operation of the unit.

SR 3.0.4 states:

Entry into a MODE or other specified condition in the Applicability of a LCO shall not be made unless the LCO's Surveillances have been met within their specified Frequency. This provision shall not prevent entry into MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

SR 3.0.4 is only applicable for entry into a MODE or other specified condition in the Applicability in MODES 1, 2, 3, and 4.

2.3 Reasons for the Proposed Changes VEGP 3&4 LCO 3.0.4 and SR 3.0.4 are overly restrictive, and the startup of a unit could be unnecessarily delayed due to the current restrictions of LCO 3.0.4. For example, a single maintenance activity that is nearly complete could result in delays and changes in the previously well-thought-out plan for returning the unit to service. In such situations, allowing the unit to enter the MODE or other specified condition in the Applicability would allow the work to be completed while reducing the likelihood of human error caused by expediting the completion of required Surveillances and maintenance activities.

The proposed changes adopt concepts that are described in TSTF-359 (Reference 1 ), which were previously approved by the NRC for Farley Nuclear Plant (Reference 5), Hatch Nuclear Plant (Reference 6), and VEGP, Units 1 and 2 (References 7 and 8). These requests were previously submitted by SNC and were approved using the CLIIP. Since TSTF-359 does not directly address the AP1000 design, the request for VEGP 3&4 is being submitted as a normal LAR. The proposed changes include the enhancements to LCO 3.0.4 from TSTF-529, which were previously adopted at Farley, Hatch, and VEGP 1 &2 (Reference 15). Allowing increased E-4

Enclosure to NL-24-0412 Evaluation of Proposed Changes flexibility in mode restraints at VEGP 3&4 would provide consistent application of LCO 3.0.4 and SR 3.0.4 across SNC's operating fleet.

2.4 Description of the Proposed Changes The TS mark-ups are provided in Attachment 1 and the revised TS pages are provided in. The TS Bases mark-ups are provided, for information only, in Attachment 3.

The proposed changes to LCO 3.0.4 incorporates the markups provided in TSTF-359, and it also includes the LCO 3.0.4 enhancements in TSTF-529. Specifically, TSTF-529 clarified LCO 3.0.4.b by placing the statement regarding exceptions in parenthesis and replacing the ending comma with a semicolon. One change (add "that") is included that is consistent with the Standard Technical Specification NUREG-1431 for Westinghouse plants. In addition, an editorial preference to add "or" to end of LCO 3.0.4.a is proposed to reduce potential confusion.

Proposed changes to LCO 3.0.4:

When an LCO is not met, entry into a MODE or other specified condition in the Applicability shall only be made:

a. When the associated ACTIONS to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time; or

b. After performance of a risk assessment addressing inoperable systems and components, consideration of the results, determination of the acceptability of entering the MODE or other specified condition in the Applicability, and establishment of risk management actions, if appropriate (exceptions to this Specification are stated in the individual Specifications); or

c. When an allowance is stated in the individual value, parameter, or other Specification.

This Specification shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

The current LCO 3.0.4 allowance is retained as LCO 3.0.4.a without the need for risk assessment because the Required Actions allow indefinite operation, which satisfies the safety function.

The current LCO 3.0.4 exceptions contained in Specifications 3.3.17, 3.3.18, and 3.4.9 are removed in the proposed changes. Also, the Note associated with Required Action A.1 and A.2 in TS 3.4.10, RCS Activity, is revised from "LCO 3.0.4 is not applicable" to "LCO 3.0.4.c is applicable."

A Note is added to TS 3.4.14, Low Temperature Overpressure Protection (L TOP), to prohibit application of LCO 3.0.4.b.

In addition to the changes described above, SR 3.0.4 is modified to state that SR 3.0.4 prohibits entry into a MODE or other specified condition in the Applicability of an LCO unless the LCO's E-5

Enclosure to NL-24-0412 Evaluation of Proposed Changes Surveillances have been met with in their specified Frequency, "except as provided by SR 3.0.3."

Currently, LCO 3.0.4 and SR 3.0.4 state that their provisions are only applicable for entry into a MODE or other specified condition in the Applicability in MODES 1, 2, 3, and 4. These applicability restrictions are deleted in the proposed changes. The provisions of LCO 3.0.4.b may be used to change MODES or other specified conditions in the Applicability while relying on ACTIONS in all MODES (unless otherwise explicitly restricted). This applies a consistent, risk-informed basis in all conditions when changing MODES or other specified conditions in the Applicability while relying on ACTIONS, except when applying LCO 3.0.4.a or LCO 3.0.4.c.

The Bases of LCO 3.0.4 and SR 3.0.4 are revised to explain the use of the new LCO 3.0.4 consistent with the TS changes. Additional complementary changes are made to the TS Bases, as shown in Attachment 3.

3.0 TECHNICAL EVALUATION

The addition of LCO 3.0.4.b, which allows entry into a MODE or other specified condition in the Applicability while relying on ACTIONS based on a risk assessment, is reasonable based on many factors. The licensee, and particularly the licensee management, is responsible for maintaining overall plant configuration and safety. Developments in the Maintenance Rule and other industry/NRC initiatives (configuration risk management, risk-informed completion time programs, etc.) enhance the tools available to licensees to assess the risk associated with various plant configurations.

The risk assessment may consider a variety of factors but will focus on managing plant risk. Consideration would be given to the probability of completing restoration such that the requirements of the LCO would be met prior to the ACTIONS requiring that the Applicability be exited. The assessment may also establish appropriate compensatory measures to enhance safe and effective operations until restoration of compliance with the LCO. The proposed changes would provide the flexibility of not restricting which MODES can be entered while relying on the ACTIONS, as do the current LCO 3.0.4 exceptions, but would add the requirement to assess the risks prior to making the MODE change when using LCO 3.0.4.b. The change will also require risk to be considered when utilizing LCO 3.0.4.b to change any MODE or other specified condition in the Applicability, not just the startup and operating MODES. These assessments are not currently required by LCO 3.0.4. In addition, the Completion Times provide a limit to how long a licensee could be in a MODE or specified condition of the Applicability without meeting the LCO requirements.

When an LCO is not met, the licensee must restore compliance with the LCO consistent with the requirements of the TS. This restoration may include corrective maintenance. The Maintenance Rule, under 10 CFR 50.65, requires that licensees assess the effect equipment maintenance will have on the plant's capability to perform safety functions before beginning any maintenance activity on structures, systems, or components (SSCs) within the scope of the rule. The final rule clarifies that these requirements apply under all conditions of operation, including shutdown, and that the assessments are to be used so that the increase in risk that may result from the maintenance activity will be managed to E-6

Enclosure to NL-24-0412 Evaluation of Proposed Changes avoid inadvertently placing the plant in a condition of significant risk. NRC Regulatory Guide 1.160, "Monitoring the Effectiveness of Maintenance at Nuclear Power Plants" (Reference 9) endorses the guidance of NUMARC 93-01, "Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants" (Reference 10),

Section 11, as an acceptable approach to meet 10 CFR 50.65(a)(4). Section 11 of NUMARC 93-01 addresses assessing and managing risk in both the operating MODES and during shutdown conditions. The risk assessments described by NUMARC 93-01 for shutdown conditions reference the guidance in NUMARC 91-06, "Guidelines for Industry Actions to Assess Shutdown Management" (Reference 11 ).

Section 11.3.1 of NUMARC 93-01 addresses assessment process, control, and responsibilities, as follows:

The process for conducting the assessment and using the result of the assessment in plant decision-making should be proceduralized. The procedures should denote responsibilities for conduct and use of the assessment, and should specify the plant functional organizations and personnel involved, including, as appropriate, operations, engineering, and risk assessment [PRA] personnel. The procedures should denote responsibilities and process for conducting the assessment for cases when the plant configuration is not covered by the normal assessment tool.

SNC utilizes a fleet process that implements 10 CFR 50.65(a)(4) and addresses a situation where entering a MODE or other specified condition in the Applicability is contemplated with plant equipment inoperable. SNC's process includes guidelines for performing the risk assessment and for establishing risk management actions prior to making a MODE change in accordance with LCO 3.0.4.b. The guidelines require that previously performed 10 CFR 50.65(a)(4) evaluations in support of a MODE change be reevaluated in the event of an unplanned condition (e.g., configuration changes, additional SSCs out of service, changes to external conditions such as weather). Final approval of the evaluation and permission to make the MODE change is granted by a senior manager.

SNC's guideline is consistent with Section 11.3.2 of NUMARC 93-01, which discusses the need to treat plant MODE changes as an emergent condition that may affect a previously performed risk assessment and would require reperformance of the assessment. When contemplating a MODE change in accordance with LCO 3.0.4.b, SNC's process utilizes the at-power configuration risk management program (CRMP) model to assess plant configurations while in MODE 1, MODE 2, or MODE 3. The VEGP 3&4 CRMP model follows the endorsed guidance in NUMARC 93-01. When the plant is in a shutdown MODE, risk assessments are conducted using the shutdown defense-in-depth model, which is based upon NUMARC 91-06.

LCO 3.0.4.b is not used unless there is a reasonable probability of completing restoration such that the requirements of the LCO would be met prior to the expiration of the ACTIONS Completion Times that would require exiting the Applicability. The NRC's oversight process monitors unplanned power changes as a performance indicator that could lead to increased oversight through inspection. Thus, the reactor oversight process provides a disincentive to entering the MODE of Applicability of an LCO, and moving up in power, when there was likelihood that the MODE of applicability would have to be subsequently exited due to failure to restore the unavailable system or component to service within the Completion Time.

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Enclosure to NL-24-0412 Evaluation of Proposed Changes An "or" is added to the end of LCO 3.0.4.a to clarify that LCO 3.0.4.b is an option, similar to the "or" at the end of LCO 3.0.4.b. This edit does not change the requirements but provides clear intention of the use and application.

The VEGP 3&4 design uses extensively analyzed and tested passive safety systems to improve the safety of the plant. These passive safety systems require no operator actions to mitigate design-basis accidents and use only natural forces such as gravity, natural circulation and compressed gas to achieve their safety function. No pumps, fans, diesels, chillers or other active machinery are used, except for a few simple valves that automatically align and actuate the passive safety systems. A review of the VEGP 3&4 safety systems was conducted to evaluate whether LCO 3.0.4.b should be prohibited for certain systems' Specifications. As a result of this review, it was determined that LCO 3.0.4.b should be prohibited for the L TOP System. Therefore, a Note is added to the TS 3.4.14 to prohibit the application of LCO 3.0.4.b. Additional details are provided in to this Enclosure.

The LCO 3.0.4.b enhancements included in TSTF-529 (i.e., placing the statement regarding exceptions in parenthesis and replacing the ending comma with a semicolon) are editorial and do not change the requirements in the TS. In Section 3.1.2 of the NRC's Final SE of TSTF-529 (Reference 3), the NRC staff found this change to be acceptable as it removes the potential for misapplication of LCO 3.0.4 allowances, and therefore provides clear and objective application of the TS Required Actions.

The current LCO 3.0.4 exceptions are deleted from TS 3.3.17, TS 3.3.18, and TS 3.4.9.

Under the proposed changes, if the LCO is not met, entry into a MODE or other specified condition in the Applicability could be made if continued operation is allowed, following the performance of a risk assessment, or if a specific allowance is stated in the Specification.

Therefore, these exceptions are no longer needed.

LCO 3.0.4.c provides for NRC approved allowances for value, parameter, and other Specifications. In the proposed changes, an allowance to use LCO 3.0.4.c is stated in TS 3.4.10, RCS Activity. The allowance is justified due to the significant conservatism incorporated into the specific activity limit, the low probably of an event which is limiting due to exceeding this limit, and the ability to restore transient specific activity excursions while the plant remains at or proceeds to power operation.

This change in LCO 3.0.4 philosophy requires a change to SR 3.0.4. If an LCO is not met, often the associated SRs are not met. If a SR is not met prior to entering the MODE or specified condition in the Applicability, SR 3.0.4 prohibits entry into the MODES and other specified conditions in the Applicability. Under SR 3.0.1, when a surveillance is not met, the LCO is declared not met and LCO 3.0.4 would also apply. Therefore, the LCO 3.0.4 allowances also need to appear in SR 3.0.4.

If it is discovered that a Surveillance has not been performed within its specified Frequency, SR 3.0.3 provides an allowance to defer declaring the affected equipment inoperable or an affected variable outside the specified limits. A 24-hour delay period is provided, to allow completion of the SR that was missed, before complying with Required Actions. The requirement to declare the LCO not met may be delayed, from the time of discovery, up to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months or up to the limit of the specified Frequency, whichever is E-8

Enclosure to NL-24-0412 Evaluation of Proposed Changes greater. A risk evaluation is required for any Surveillance delayed greater than 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , and the risk impact is managed.

If a Surveillance is missed and the delay period allowed by SR 3.0.3 is used, LCO 3.0.4 would not apply because the affected equipment is OPERABLE. However, SR 3.0.4 requires Surveillances to be met within their specified Frequency prior to entry into a MODE or other specified condition in the Applicability. If SR 3.0.3 is applied to a missed Surveillance and the requirement to declare the LCO not met is delayed, then the existing SR 3.0.4 only allows the delay to be applied in the MODE or other specified condition in the Applicability in which the plant is operating at the time of discovery of the missed Surveillance. While this provision does not prevent a shutdown, the existing SR 3.0.4 would prevent entry into a higher MODE of operation with a Surveillance that had not been performed within its specified Frequency.

To address this situation, SR 3.0.4 is modified to prohibit entry into a MODE or other specified condition in the Applicability of an LCO unless the associated Surveillances have been met within their specified Frequency, except as provided by SR 3.0.3. The Bases for SR 3.0.4 are modified to provide the flexibility for entry into higher MODES, with a missed Surveillance, since the equipment remains OPERABLE during the SR 3.0.3 delay period.

The revised SR 3.0.4 Bases state, "SR 3.0.4 does not restrict changing MODES or other specified conditions of the Applicability when a Surveillance has not been performed within the specified Frequency, provided the requirement to declare the LCO not met has been delayed in accordance with SR 3.0.3."

Complementary changes to these TS Sections changes are made to the Bases of LCO 3.0.4 and SR 3.0.4 as shown in Attachment 3.

These proposed changes provide greater consistency with other Standard Technical Specifications and provide improved flexibility consistent with maintaining safe plant operations.

On November 19, 2024 (see ADAMS Accession Numbers ML24312A248 and ML24317A223).

SNC has expressed its intent to request TS changes to revise unnecessarily restrictive and potentially conflicting Required Actions that may also restrict mode changes while shutdown (i.e., during MODES 5 and 6). An assessment of impacts of the proposed changes to the shutdown TS did not identify any impacts to the proposed changes in this request.

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements/Criteria In 10 CFR 50.36, the NRC established its regulatory requirements related to the content of TS.

Pursuant to 10 CFR 50.36, TS 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 (LCOs);

(3) surveillance requirements (SRs);

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Enclosure to NL-24-0412 Evaluation of Proposed Changes (4) design features; and (5) administrative controls.

The rule does not specify the particular requirements to be included in a plant's TS. As stated in 10 CFR 50.36(c)(2)(i), the "[LCOs] are the lowest functional capability or performance levels of equipment required for safe operation of the facility. When a [LCO] of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the [TS]

.... " The LCOs are contained in Sections 3.1 through 3.9 of the VEGP 3&4 TS. TS Section 3.0, on LCO and SR Applicability, provides details or ground rules for complying with the LCOs.

LCO 3.0.4 and SR 3.0.4 address requirements for LCO compliance when transitioning between modes of operation.

Proposed LCO 3.0.4.a retains the current LCO 3.0.4 allowance without the need for risk assessment because the Required Actions allow indefinite operation, which satisfies the safety function. Proposed LCO 3.0.4.b allows for the performance of a risk assessment to determine the acceptability of entering a MODE or other specified condition in the Applicability, and through the establishment of risk management actions, if appropriate. LCO 3.0.4.c provides for NRC approved allowances for value, parameter, and other Specifications.

The proposed changes are consistent with the requirements of 10 CFR 50.36.

Use of the proposed LCO 3.0.4.b to enter a MODE or other specified condition in the Applicability relies on risk assessment approaches and tools that are also used to comply with 10 CFR 50.65(a)(4), which requires licensees to assess and manage the risk increase that may result from performing maintenance activities. The proposed changes do not impact compliance with the Maintenance Rule.

4.2 Precedent On April 6, 2022, Dominion Energy submitted a request to revise the TS for Millstone Power Station, Units 2 and 3 (Reference 12). The amendment (Reference 13) revised the TS requirements for mode change limitations to adopt the provisions of TSTF-359, "Increased Flexibility in Mode Restraints." The availability of TSTF-359 for adoption by licensees was announced in the Federal Register on April 4, 2003 (68 FR 16579) as part of the CLIIP. The proposed changes to the VEGP 3&4 TS are similar to the change requested for Millstone; however, this request is being processed as a normal license amendment since TSTF-359 does not directly address the AP1000 design (e.g., does not include TS markups for AP1000).

On June 27, 2017, the NRC approved SNC's request to adopt TSTF-529, "Clarify Use and Application Rules" (References 14 and 15). Note that the broader scope of changes in TSTF-529 (i.e., those not associated with LCO 3.0.4) are not included in this request. SNC determined that it would be prudent to adopt the LCO 3.0.4 enhancements from TSTF-529, in conjunction with the proposed changes, to limit the potential for misapplication of LCO 3.0.4, as documented in References 2 and 3.

4.3 Significant Hazards Evaluation Southern Nuclear Operating Company (SNC) requests an amendment to the Combined License (COL) for Vogtle Electric Generating Plant (VEGP), Units 3 and 4 (License Nos. NPF-91 and NPF-92, respectively). The proposed amendment would revise Appendix A, Technical E-10

Enclosure to NL-24-0412 Evaluation of Proposed Changes Specifications (TS), of the COL to increase flexibility in mode restraints. The proposed changes adopt concepts similar to those described in Technical Specification Task Force (TSTF) 359, Revision 9, "Increased Flexibility in Mode Restraints," with enhancements similar to those identified in TSTF-529, Revision 4, "Clarify Use and Application Rules," for Limiting Condition for Operation (LCO) 3.0.4.

An evaluation to determine whether or not a significant hazards consideration is involved with the proposed amendment was completed by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:

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

Response: No The proposed changes allow entry into a mode or other specified condition in the applicability of a TS, while in a TS condition statement and the associated required actions of the TS. Being in a TS condition and the associated required actions is not an initiator of any accident previously evaluated. Therefore, the probability of an accident previously evaluated is not significantly increased. The consequences of an accident while relying on required actions as allowed by proposed LCO 3.0.4, are no different than the consequences of an accident while entering and relying on the required actions while starting in a condition of applicability of the TS. Therefore, the consequences of an accident previously evaluated are not significantly affected by this change. The addition of a requirement to assess and manage the risk introduced by this change will further minimize possible concerns.

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

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

Response: No The proposed changes do not involve a physical alteration of the plant (no new or different type of equipment will be installed). Entering into a mode or other specified condition in the applicability of a TS, while in a TS condition statement and the associated required actions of the TS, will not introduce new failure modes or effects and will not, in the absence of other unrelated failures, lead to an accident whose consequences exceed the consequences of accidents previously evaluated. The addition of a requirement to assess and manage the risk introduced by this change will further minimize possible concerns.

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

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No E-11

Enclosure to NL-24-0412 Evaluation of Proposed Changes The proposed changes allow entry into a mode or other specified condition in the applicability of a TS, while in a TS condition statement and the associated required actions of the TS. The TS allow operation of the plant without the full complement of equipment through the conditions for not meeting the TS LCOs. The risk associated with this allowance is managed by the imposition of required actions that must be performed within the prescribed completion times. The net effect of being in a TS condition on the margin of safety is not considered significant. The proposed changes do not alter the required actions or completion times of the TS. The proposed changes allow TS conditions to be entered, and the associated required actions and completion times to be used in new circumstances. This use is predicated upon the performance of a risk assessment and the management of plant risk. The change also eliminates current allowances for utilizing required actions and completion times in similar circumstances, without assessing and managing risk. The net change to the margin of safety is insignificant.

Therefore, the proposed changes do not involve a significant reduction in a margin of safety.

Based upon the reasoning presented above, it is concluded that the requested changes involve no significant hazards consideration under the standards set forth in 10 CFR 50.92(c),

"Issuance of Amendment," and, accordingly, a finding of "no significant hazards consideration" is justified.

4.4 Conclusions In conclusion, based on 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 Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or the health and safety of the public.

5.0 ENVIRONMENTAL CONSIDERATION

The proposed changes to the Technical Specifications (TS) are described in Section 2 of this Enclosure, which require a license amendment. SNC has evaluated this license amendment request against the criteria for identification of licensing and regulatory actions requiring environmental assessment in accordance with 10 CFR 51.21.

The requested amendment would change the TS; however, meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9), in that the amendment would not involve (i) a significant hazards consideration, (ii) a significant change in the types or 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 criteria 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.

E-12

Enclosure to NL-24-0412 Evaluation of Proposed Changes

6.0 REFERENCES

1. NEI Letter to NRC transmitting TSTF-359, Revision 9, "Increased Flexibility in Mode Restraints," April 28, 2003 (ML031190607)

2. TSTF Letter to NRC transmitting TSTF-529, Revision 4, "Clarify Use and Application Rules," February 29, 2016 (ML16062A271)

3. NRC Final Safety Evaluation of Traveler TSTF-529, Revision 4, "Clarify Use and Application Rules," April 21, 2016 (ML16060A440)

4. NRC Letter to SNC, "Vogtle Electric Generating Plant, Units 3 and 4 - Issuance of Amendments: Technical Specification Surveillance Requirement 3.0.3 for Never-Performed Surveillance," April 26, 2023 (ML23072A271)

5. NRC Letter to SNC, "Joseph M. Farley Nuclear Plant, Units 1 and 2 - Issuance of Amendment Re: Increasing Flexibility in Mode Restraints," February 22, 2006 (ML060310207)

6. NRC Letter to SNC, "Edwin I. Hatch Nuclear Plant, Units 1 and 2 - Issuance of Amendments Re: Increasing Flexibility in Mode Restraints," December 13, 2005 (ML053110117)

7. NRC Letter to SNC, "Vogtle Electric Generating Plant, Units 1 and 2 - Issuance of Amendment Re: Increasing Flexibility in Mode Restraints," June 24, 2005 (ML051710090)

8. NRC Letter to SNC, "Vogtle Electric Generating Plant, Units 1 and 2, Issuance of Amendments Regarding Increasing Flexibility in Mode Restraints for Auxiliary Feedwater System," June 14, 2006 (ML061840495)

9. NRC Regulatory Guide 1.160, "Monitoring the Effectiveness of Maintenance at Nuclear Power Plants", Revision 4, August 2018 (ML18220B281)

10. NU MARC 93-01, "Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants," Revision 4F, April 2018 (ML18120A069)

11. NUMARC 91-06, "Guidelines for Industry Actions to Assess Shutdown Management,"

December 1991 (ML14365A203)

12. Dominion Energy Letter to NRC, "Dominion Energy Nuclear Connecticut, Inc. Millstone Power Station Units 2 and 3 Application for Technical Specification Change Regarding Mode Change Limitations Using the Consolidated Line Item Improvement Process," April 6, 2022 (ML22096A221)

13. NRC Letter to Dominion, "Millstone Power Station, Unit Nos. 2 and 3 - Issuance of Amendment Nos. 345 and 285 Regarding Adoption of Technical Specification Task Force-359, "Increased Flexibility in Mode Restraints," March 16, 2023 (ML23058A454)

14. SNC (Farley, Hatch, and Vogtle 1 &2) Letter to NRC, "License Amendment Request to Revise Technical Specifications to Adopt TSTF-529, Revision 4, "Clarify Use and Application Rules," December 1, 2016 (ML16340A005)

15. NRC Letter to SNC, "Joseph M. Farley Nuclear Plant, Units 1 and 2; Vogtle Electric Generating Plant, Units 1 and 2; and Edwin I. Hatch Nuclear Plant, Unit Nos. 1 and 2 -

Issuance of Amendments Regarding the Adoption of TSTF-529, Revision 4, "Clarify Use and Application Rules", June 27, 2017 (ML17137A041)

E-13

ATTACHMENT 1 to NL-24-0412 Proposed Technical Specification Change (Mark-ups)

License Amendment Request to Increase Flexibility in Mode Restraints Red line deletion and blue underlined additions based on TSTF-359.

Green additions based on TSTF-529 where identified in the margins.

Purple additions based on NUREG-1431 standard language where identified in the margins.

Technical Specifications LCO Applicability 3.0 3.0 LIMITING CONDITIONS FOR OPERATION (LCO) APPLICABILITY LCO 3.0.1 LCO 3.0.2 LCO 3.0.3 LCO 3.0.4 INSERT LCO 3.0.4 VEGP Units 3 and 4 LCOs shall be met during the MODES or other specified conditions in the Applicability, except as provided in LCO 3.0.2 and LCO 3.0.7.

Upon discovery of a failure to meet an LCO, the Required Actions of the associated Conditions shall be met, except as provided in LCO 3.0.5 and 3.0.6.

If the LCO is met, or is no longer applicable prior to expiration of the specified Completion Time(s), completion of the Required Action(s) is not required, unless otherwise stated.

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. Action shall be initiated within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months to place the unit, as applicable, in:

a.

MODE 3 within 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months ; and

b.

MODE 4 within 13 hours1.50463e-4 days 0.00361 hours 2.149471e-5 weeks 4.9465e-6 months ; and

c.

MODE 5 within 37 hours4.282407e-4 days 0.0103 hours 6.117725e-5 weeks 1.40785e-5 months .

Exceptions to this Specification are stated in the individual Specifications.

Where corrective measures are completed that permit operation in accordance with the LCO or ACTIONS, completion of the actions required by LCO 3.0.3 is not required.

LCO 3.0.3 is only applicable in MODES 1, 2, 3, and 4.

3.0 - 1 Amendment No.

~ (Unit 3)

Amendment No.

~ (Unit 4)

edit INSERT for LCO 3.0.4 When an LCO is not met, entry into a MODE or other specified condition in the Applicability shall Ret--0....oJ.y_be made mwept 1,vhen~

a. When the associated ACTIONS to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time;.,. or

b. After performance of a risk assessment addressing inoperable systems and components. consideration of the results. determination of the acceptability of entering the MODE or other specified condition in the Applicability. and establishment of risk management actions. if appropriate (exceptions to this Specification are stated in the individual Specifications): or

c. When an allowance is stated in the individual value. parameter. or other Specification.

This Specification shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

Exceptions to this Specification are stated in the individual Specifications.

LCO 3.0.4 is only applicable for entry into a MODE or other specified condition in the Applicability in MODES 1, 2, 3, and 4.

3.0 SR Applicability SR 3.0.4 INSERT SR 3.0.4 VEGP Units 3 and 4 Technical Specifications 3.0 - 4 SR Applicability 3.0 Amendment No.

~ (Unit 3)

Amendment No.

~ (Unit 4)

INSERT for SR 3.0.4 Entry into a MODE or other specified condition in the Applicability of a-an LCO shall mt-Q.!J!y_be made unless when the LCO's Surveillances have been met within their specified Frequencv. except as provided by SR 3.0.3. When an LCO is not met due to Surveillances not having been met. entry into a MODE or other specified condition in the Applicability shall only be made in accordance with LCO 3.0.4.

This provision shall not prevent entry into MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

SR 3.0.4 is only applicable for entry into a MODE or other specified condition in the Applicability in MODES 1, 2, 3, and 4.

Technical Specifications 3.3 INSTRUMENTATION 3.3.17 Post Accident Monitoring (PAM) Instrumentation PAM Instrumentation 3.3.17 LCO 3.3.17 The PAM instrumentation for each Function in Table 3.3.17-1 shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, and 3.

ACTIONS

- NOTES -

Separate Condition entry is allowed for each Function.

CONDITION REQUIRED ACTION COMPLETION TIME A.

One or more Functions A.1 Restore required channel 30 days with one required channel inoperable.

B.

Required Action and B.1 associated Completion Time of Condition A not met.

C.

One or more Functions C.1 with two required channels inoperable.

D.

Required Action and 0.1 associated Completion Time of Condition C not met.

E.

As required by Required E.1 Action 0.1 and referenced in AND Table 3.3.17-1.

E.2 VEGP Units 3 and 4 to OPERABLE status.

Initiate action in accordance with Specification 5.6.5.

Restore one channel to OPERABLE status.

Enter the Condition referenced in Table 3. 3.17 -1 for the channel.

Be in MODE 3.

Be in MODE 4.

3.3.17 - 1 Immediately 7 days Immediately 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months 12 hours Amendment No.

~ (Unit 3)

Amendment No.

~ (Unit 4)

Technical Specifications 3.3 INSTRUMENTATION 3.3.18 Remote Shutdown Workstation (RSW)

LCO 3.3.18 The RSW shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, and 3.

RSW 3.3.18 MODE 4 with Reactor Coolant System (RCS) average temperature (T avg )

~ 350°F.

~~ B=!,..,.

CONDITION A.

RSW inoperable.

B.

Required Action and associated Completion Time not met.

A.1 B.1 AND B.2 REQUIRED ACTION Restore to OPERABLE status.

Be in MODE 3.

Be in MODE 4 with T avg < 350°F.

SURVEILLANCE REQUIREMENTS SURVEILLANCE COMPLETION TIME 30 days 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months 12 hours FREQUENCY SR 3.3.18.1 Verify each required transfer switch is capable of 24 months SR 3.3.18.2 SR 3.3.18.3 performing the required function.

Verify the RSW communicates indication and controls 24 months with Division A, B, C and D of the Protection and Safety Monitoring System (PMS).

Verify the OPERABILITY of the RSW hardware and 24 months software.

VEGP Units 3 and 4 3.3.18 - 1 Amendment No.

~ (Unit 3)

Amendment No.

~ (Unit 4)

Technical Specifications RCS Leakage Detection Instrumentation 3.4.9

==-"""'-=' -- n

_ 1'W 1,1., ___,/-,----------- l -? -~-------------/ -;------------.!--.-------

CONDITION REQUIRED ACTION COMPLETION TIME A.

One required A.1 Restore two containment 14 days containment sump sump channels to channel inoperable.

OPERABLE status.

B.

Two required 8.1 containment sump

- NOTE -

channels inoperable.

Not required until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after establishment of steady state operation.

Perform SR 3.4. 7.1.

Once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months AND 8.2 Restore one containment 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months sump channel to OPERABLE status.

C.

Containment C.1.1 Analyze grab samples of Once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months atmosphere F18 containment atmosphere.

particulate monitor inoperable.

OR C.1.2

- NOTE -

Not required until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after establishment of steady state operation.

Perform SR 3.4. 7.1.

Once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months AND C.2 Restore containment 30 days atmosphere F18 particulate monitor to OPERABLE status.

VEGP Units 3 and 4 3.4.9 - 2 Amendment No.

1 (Unit 3)

Amendment No.

.:1 (Unit 4)

Technical Specifications RCS Specific Activity 3.4.10 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.10 RCS Specific Activity LCO 3.4.10 The specific activity of the reactor coolant shall be within limits.

APPLICABILITY:

MODES 1 and 2.

MODE 3 with RCS average temperature (T avg ) ~ 500°F.

ACTIONS CONDITION A.

DOSE EQUIVALENT 1-131 > 1.0 µCi/gm.

B.

DOSE EQUIVALENT XE-133 > 280 µCi/gm.

C.

Required Action and associated Completion Time of Condition A not met.

OR DOSE EQUIVALENT 1-131 > 60 µCi/gm.

VEGP Units 3 and 4 LCO 3.0.4.c is applicable I REQUIRED ACTlgN COMPLETION TIME J ------------

- NOTE -

~C:'.:: :.~.,1 ;:

~ ~~ ::~sagj-..._

A.1 Verify DOSE EQUIVALENT 1-131

60 µCi/gm.

AND A.2 Restore DOSE EQUIVALENT 1-131 to within limit.

B.1 Be in MODE 3 with T avg

< 500°F.

C.1 Be in MODE 3 with T avg

< 500°F.

3.4.10-1 Once per 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months 48 hours 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months 6 hours Amendment No.

~ (Unit 3)

Amendment No.

~ (Unit 4)

Technical Specifications LTOP 3.4.14 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.14 Low Temperature Overpressure Protection (LTOP)

LCO 3.4.14 APPLICABILITY:

At least one of the following overpressure protection methods shall be OPERABLE, with the accumulators isolated:

a.

Two Normal Residual Heat Removal System (RNS) suction relief valves and Chemical and Volume Control System (CVS) makeup line containment isolation valve, CVS-PL-V091, closed; or

b.

The RCS depressurized and an RCS vent of~ 4.15 square inches.

- NOTE -

Accumulator isolation is only required when accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature allowed by the PIT limit curves provided in the PTLR.

MODE 4 when any cold leg temperature is ::; 275°F, MODE 5, MODE 6 when the reactor vessel head is on.

INSERT LCO 3.4.14 CONDITION A.

An accumulator not isolated when the accumulator pressure is greater than or equal to the maximum RCS pressure for existing cold leg temperature allowed in the PTLR.

VEGP Units 3 and 4 A.1 REQUIRED ACTION Isolate affected accumulator.

3.4.14 - 1 COMPLETION TIME 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Amendment No. ~

(Unit 3)

Amendment No. ~

(Unit 4)

INSERT for LCO 3.4.14 ACTIONS ACTIONS

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

LCO 3.0.4.b is not applicable.

ATTACHMENT 2 to NL-24-0412 Clean Revised Technical Specification Pages License Amendment Request to Increase Flexibility in Mode Restraints

Technical Specifications LCO Applicability 3.0 3.0 LIMITING CONDITIONS FOR OPERATION (LCO) APPLICABILITY LCO 3.0.1 LCO 3.0.2 LCO 3.0.3 LCO 3.0.4 VEGP Units 3 and 4 LCOs shall be met during the MODES or other specified conditions in the Applicability, except as provided in LCO 3.0.2 and LCO 3.0.7.

Upon discovery of a failure to meet an LCO, the Required Actions of the associated Conditions shall be met, except as provided in LCO 3.0.5 and 3.0.6.

If the LCO is met, or is no longer applicable prior to expiration of the specified Completion Time(s), completion of the Required Action(s) is not required, unless otherwise stated.

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. Action shall be initiated within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months to place the unit, as applicable, in:

a.

MODE 3 within 7 hours8.101852e-5 days 0.00194 hours 1.157407e-5 weeks 2.6635e-6 months ; and

b.

MODE 4 within 13 hours1.50463e-4 days 0.00361 hours 2.149471e-5 weeks 4.9465e-6 months ; and

c.

MODE 5 within 37 hours4.282407e-4 days 0.0103 hours 6.117725e-5 weeks 1.40785e-5 months .

Exceptions to this Specification are stated in the individual Specifications.

Where corrective measures are completed that permit operation in accordance with the LCO or ACTIONS, completion of the actions required by LCO 3.0.3 is not required.

LCO 3.0.3 is only applicable in MODES 1, 2, 3, and 4.

When an LCO is not met, entry into a MODE or other specified condition in the Applicability shall only be made:

a.

When the associated Actions to be entered permit continued operation in the MODE or other specified condition in the Applicability for an unlimited period of time; or

b. After performance of a risk assessment addressing inoperable systems and components, consideration of the results, determination of the acceptability of entering the MODE or other specified condition in the Applicability, and establishment of risk management actions, if appropriate (exceptions to this Specification are stated in the individual Specification); or 3.0 - 1 Amendment No.

Amendment No.

(Unit 3)

(Unit 4)

3.0 LCO Applicability LCO 3.0.4

( continued)

LCO 3.0.5 LCO 3.0.6 LCO 3.0.7 VEGP Units 3 and 4 Technical Specifications LCO Applicability 3.0

c.

When an allowance is stated in the individual value, parameter, or other Specification.

This Specification shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

Equipment removed from service or declared inoperable to comply with ACTIONS may be returned to service under administrative control solely to perform testing required to demonstrate its OPERABILITY or the OPERABILITY of other equipment. This is an exception to LCO 3.0.2 for the system returned to service under administrative control to perform the test required to demonstrate OPERABILITY.

When a supported system LCO is not met solely due to a support system LCO not being met, the Conditions and Required Actions associated with this supported system are not required to be entered. Only the support system LCO ACTIONS are required to be entered. This is an exception to LCO 3.0.2 for the supported system. In this event, additional evaluations and limitations may be required in accordance with Specification 5.5.7, "Safety Function Determination Program (SFDP)." If a loss of safety function is determined to exist by this program, the appropriate Conditions and Required Actions of the LCO in which the loss of safety function exists are required to be entered.

When a support system's Required Action directs a supported system to be declared inoperable or directs entry into Conditions and Required Actions for a supported system, the applicable Conditions and Required Actions shall be entered in accordance with LCO 3.0.2.

Test Exception LCOs 3.1.8 and 3.1.10 allow specified Technical Specification (TS) requirements to be changed to permit performance of special tests and operations. Unless otherwise specified, all other TS requirements remain unchanged. Compliance with Test Exception LCOs is optional. When a Test Exception LCO is desired to be met but is not met, the ACTIONS of the Test Exception LCO shall be met. When a Test Exception LCO is not desired to be met, entry into a MODE or other specified condition in the Applicability shall be made in accordance with the other applicable Specifications.

3.0 - 2 Amendment No.

Amendment No.

(Unit 3)

(Unit 4)

3.0 LCO Applicability LCO 3.0.7

( continued)

VEGP Units 3 and 4 Technical Specifications LCO Applicability 3.0 Additionally, for Unit 4 only, Combined License Condition 2.0(9) provides temporary exclusions for specified TS requirements prior to becoming permanently effective at initial criticality of the reactor core. Compliance with TS requirements that are excluded from becoming effective while operating in MODES 4, 5, and 6 in accordance with the COL Condition is optional.

3.0 - 2a Amendment No.

Amendment No.

(Unit 3)

(Unit 4)

3.0 SR Applicability SR 3.0.4 VEGP Units 3 and 4 Technical Specifications SR Applicability 3.0 Entry into a MODE or other specified condition in the Applicability of an LCO shall only be made when the LCO's Surveillances have been met within their specified Frequency, except as provided by SR 3.0.3. When an LCO is not met due to Surveillances not having been met, entry into a MODE or other specified condition in the Applicability shall only be made in accordance with LCO 3.0.4.

This provision shall not prevent entry into MODES or other specified conditions in the Applicability that are required to comply with ACTIONS or that are part of a shutdown of the unit.

3.0 - 4 Amendment No.

Amendment No.

(Unit 3)

(Unit 4)

Technical Specifications 3.3 INSTRUMENTATION 3.3.17 Post Accident Monitoring (PAM) Instrumentation PAM Instrumentation 3.3.17 LCO 3.3.17 The PAM instrumentation for each Function in Table 3.3.17-1 shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, and 3.

ACTIONS

- NOTE -

Separate Condition entry is allowed for each Function.

CONDITION REQUIRED ACTION COMPLETION TIME A.

One or more Functions A.1 Restore required channel 30 days with one required channel inoperable.

B.

Required Action and B.1 associated Completion Time of Condition A not met.

C.

One or more Functions C.1 with two required channels inoperable.

D.

Required Action and D.1 associated Completion Time of Condition C not met.

E.

As required by Required E.1 Action D.1 and referenced in AND Table 3.3.17-1.

E.2 VEGP Units 3 and 4 to OPERABLE status.

Initiate action in accordance with Specification 5.6.5.

Restore one channel to OPERABLE status.

Enter the Condition referenced in Table 3.3.17-1 for the channel.

Be in MODE 3.

Be in MODE 4.

3.3.17 - 1 Immediately 7 days Immediately 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months 12 hours Amendment No.

Amendment No.

(Unit 3)

(Unit 4)

Technical Specifications 3.3 INSTRUMENTATION 3.3.18 Remote Shutdown Workstation (RSW)

LCO 3.3.18 The RSW shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, and 3.

RSW 3.3.18 MODE 4 with Reactor Coolant System (RCS) average temperature (Tav9)

~ 350°F.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

RSW inoperable.

A.1 Restore to OPERABLE 30 days status.

B.

Required Action B.1 Be in MODE 3.

6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and associated Completion Time not AND met.

B.2 Be in MODE 4 with 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months Tavg < 350°F.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.3.18.1 SR 3.3.18.2 SR 3.3.18.3 Verify each required transfer switch is capable of 24 months performing the required function.

Verify the RSW communicates indication and controls 24 months with Division A, B, C and D of the Protection and Safety Monitoring System (PMS).

Verify the OPERABILITY of the RSW hardware and 24 months software.

VEGP Units 3 and 4 3.3.18 - 1 Amendment No.

Amendment No.

(Unit 3)

(Unit 4)

ACTIONS CONDITION A.

One required containment sump channel inoperable.

B.

Two required containment sump channels inoperable.

C.

Containment atmosphere F18 particulate monitor inoperable.

VEGP Units 3 and 4 Technical Specifications RCS Leakage Detection Instrumentation 3.4.9 A.1 B.1 AND B.2 C.1.1 OR C.1.2 AND C.2 REQUIRED ACTION COMPLETION TIME Restore two containment 14 days sump channels to OPERABLE status.

- NOTE -

Not required until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after establishment of steady state operation.

Perform SR 3.4.7.1.

Once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months Restore one containment 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months sump channel to OPERABLE status.

Analyze grab samples of Once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months containment atmosphere.

- NOTE -

Not required until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after establishment of steady state operation.

Perform SR 3.4.7.1.

Once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months Restore containment 30 days atmosphere F18 particulate monitor to OPERABLE status.

3.4.9 - 2 Amendment No.

Amendment No.

(Unit 3)

(Unit 4)

Technical Specifications 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.10 RCS Specific Activity RCS Specific Activity 3.4.10 LCO 3.4.10 The specific activity of the reactor coolant shall be within limits.

APPLICABILITY:

MODES 1 and 2.

MODE 3 with RCS average temperature (Tav9) ~ 500°F.

ACTIONS CONDITION A.

DOSE EQUIVALENT 1-131 > 1.0 µCi/gm.

B.

DOSE EQUIVALENT XE-133 > 280 µCi/gm.

C.

Required Action and associated Completion Time of Condition A not met.

OR DOSE EQUIVALENT 1-131 > 60 µCi/gm.

VEGP Units 3 and 4 REQUIRED ACTION COMPLETION TIME

- NOTE -

LCO 3.0.4.c is applicable.

A.1 Verify DOSE EQUIVALENT 1-131

60 µCi/gm.

AND A.2 Restore DOSE EQUIVALENT 1-131 to within limit.

B.1 Be in MODE 3 with Tavg

< 500°F.

C.1 Be in MODE 3 with Tav9

< 500°F.

3.4.10 - 1 Once per 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months 48 hours 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months 6 hours Amendment No.

Amendment No.

(Unit 3)

(Unit 4)

Technical Specifications LTOP 3.4.14 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.14 Low Temperature Overpressure Protection (LTOP)

LCO 3.4.14 APPLICABILITY:

ACTIONS At least one of the following overpressure protection methods shall be OPERABLE, with the accumulators isolated:

a.

Two Normal Residual Heat Removal System (RNS) suction relief valves and Chemical and Volume Control System (CVS) makeup line containment isolation valve, CVS-PL-V091, closed; or

b.

The RCS depressurized and an RCS vent of ~ 4.15 square inches.

- NOTE -

Accumulator isolation is only required when accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature allowed by the PIT limit curves provided in the PTLR.

MODE 4 when any cold leg temperature is ::; 275°F, MODE 5, MODE 6 when the reactor vessel head is on.

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

LCO 3.0.4.b is not applicable.

CONDITION A.

An accumulator not isolated when the accumulator pressure is greater than or equal to the maximum RCS pressure for existing cold leg temperature allowed in the PTLR.

VEGP Units 3 and 4 A.1 REQUIRED ACTION Isolate affected accumulator.

3.4.14 - 1 COMPLETION TIME 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months Amendment No.

Amendment No.

(Unit 3)

(Unit 4)

ATTACHMENT 3 to NL-24-0412 Associated Technical Specification Bases Changes

{for information only)

License Amendment Request to Increase Flexibility in Mode Restraints Red deletion and blue underlined additions based on TSTF-359.

Light blue deletion and Green underlined additions based on TSTF-529 where identified in the margins.

Purple deletions and purple underlined additions based on NUREG-1431 standard language where identified in the margins.

Technical Specifications Bases BASES LCO Applicability B 3.0 LCO 3.0.3 (continued)

LCO 3.0.4 INSERT for LCO 3.0.4 BASES The time limits of Specification 3.0.3 allow 37 hours4.282407e-4 days 0.0103 hours 6.117725e-5 weeks 1.40785e-5 months for the unit to be in MODE 5 when a shutdown is required during MODE 1 operation. If the unit is in a lower MODE of operation when a shutdown is required, the time limit for reaching the next lower MODE applies. If a lower MODE is reached in less time than allowed, however, the total allowable time to reach MODE 5, or other applicable MODE is not reduced. For example, if MODE 3 is reached in 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months , then the time allowed for reaching MODE 4 is the next 11 hours1.273148e-4 days 0.00306 hours 1.818783e-5 weeks 4.1855e-6 months , because the total time for reaching MODE 4 is not reduced from the allowable limit of 13 hours1.50463e-4 days 0.00361 hours 2.149471e-5 weeks 4.9465e-6 months . Therefore, if remedial measures are completed that would permit a return to MODE 1, a penalty is not incurred by having to reach a lower MODE of operation in less than the total time allowed.

Compliance with the time limits of Specification 3.0.3 rely on the use of nonsafety-related systems, which are not governed by Technical Specification LCOs.

In MODES 1, 2, 3, and 4, LCO 3.0.3 provides actions for Conditions not covered in other Specifications. The requirements of LCO 3.0.3 do not apply in other specified conditions of the Applicability (unless in MODE 1, 2, 3, or 4) because the ACTIONS of individual Specifications sufficiently define the remedial measures to be taken. The requirements of LCO 3.0.3 do not apply in MODES 5 and 6 because the unit is already in the most restrictive condition required by LCO 3.0.3.

Exceptions to 3.0.3 are provided in instances where requiring a unit shutdown in accordance with LCO 3.0.3, would not provide appropriate remedial measures for the associated condition of the unit. An example of this is in LCO 3.7.5, Spent Fuel Pool Water Level. This Specification has an Applicability of "At all times." Therefore, this LCO can be applicable in any or all MODES. If the LCO and the Required Actions of LCO 3.7.5 are not met while in MODE 1, 2, or 3, there is no safety benefit to be gained by placing the unit in a shutdown condition. The Required Action of LCO 3.7.5 of "Suspend movement of irradiated fuel assemblies in the spent fuel pool" is the appropriate Required Action to complete in lieu of the actions of LCO 3.0.3. These exceptions are addressed in the individual Specifications.

LGO 3.0.4 establishes lin=iitations on ohanges in MODe£ or other speei~ied eonditions in the Applieability when an LGO is not n=iet It preoludes plaoing the unit in a MODe or other speoi~ied oondition stated

--> that l\\pplioability (e.g., l\\pplioability desired to be entered) when the

~allowing mcist VEGP Units 3 and 4 B 3.0 - 4 Revision +4

Technical Specifications Bases BASES LCO Applicability B 3.0 LCO 3.0.4 (continued)

VEGP Units 3 and 4 GoR1plianoe with Reqc1iFed 11\\otions that pen=i=iit oontinc1ed opemtion of the c1nit foF an c1nlin=iited period of tiR1e in a MODE: or other speeified eondition prn1o1ides an aooeptable le1o1el of safety foF oontinc1ed opemtion. This is withoc1t FegaFd to the statc1s of the c1nit beforn OF afteF the MODE ohange.

Therefore, in sc1eh eases, entry into a MODE: or other speeified eondition in the 11\\pplioability n=iay be R1ade in aoooFdanoe with the prn1o1isions of the Reqc1iFed 11\\otions. The pF01o1isions of this £peoifioation shoc1ld not be inteFpFeted as endoFsing the failc1Fe to m<eFoise the good pFaotioe of rnstoFing systen=is OF oon=iponents to OPERI\\BLE statc1s beforn enteFing an assooiated MODE OF otheF speoified oondition in the 11\\pplioability.

The pF01o1isions of LGO d.0.4 shall not pFe1o1ent ohanges in MODE£ OF other speeified eonditions in the /\\pplieability that are reqc1ired to eoR1ply with 11\\GTION£. In addition, the prn1o1isions of LGO d.0.4 shall not prn1o1ent ohanges in MODE£ OF otheF speoified oonditions in the 11\\pplioability that rnsc1lts fFon=i any c1nit shc1tdown.

l in

~-ti~R e-Rst

£c1FVeillanoes do not ha1o1e to be peFfoFn=ied on the assooiated inopeFable eqc1ipn=ient (oF on 1o1aFiables oc1tside the speoified lin=iits), as peFn=iitted by SR d.0.1. Therefore, ehanging MODE:£ or other speeified eonditions while in an 11\\GTIO~Jg Condition, in GOR1plianoe with LGO d.0.4 OF whern an mcoeption to LGO d.0.4 is stated, is not a 1o1iolation of £R d.0.1 OF B 3.0 - 5 Revision +4

INSERT for LCO 3.0.4 BASES LCO 3.0.4 establishes limitations on changes in MODES or other specified conditions in the Applicability when an LCO is not met. It allows precludes placing the unit in a MODE or other specified condition stated i.o_that Applicability (e.g., the Applicability desired to be entered) when unit conditions are such that the requirements of the LCO would not be met. in accordance with either LCO 3.0.4.a, LCO 3.0.4.b, or LCO 3.0.4.c. tRe following exist:

a. Unit conditions are such that the requirements of the LCO 1,vould not be met in the Applicability desired to be entered; and

b. Continued noncompliance with the LCO requirements, if the Applicability were entered, would result in the unit being required to exit the Applicability desired to be entered to comply 1,vith the Required Actions.

LCO 3.0.4.a allows entry into a MODE or other specified condition in the Applicability with the LCO not met when the associated ACTIONS to be entered following entry into the MODE or other specified condition in the Applicability will permit continued operation within the MODE or other specified condition for an unlimited period of time. Compliance with ACTIONS Required Actions that permit continued operation of the unit for an unlimited period of time in a MODE or other specified condition provides an acceptable level of safety for continued operation. This is without regard to the status of the unit before or after the MODE change.

Therefore, in such cases, entry into a MODE or other specified condition in the Applicability may be made in accordance with the provisions of and the Required Actions followed after entry into the Applicability.

For example, LCO 3.0.4.a may be used when the Required Action to be entered states that an inoperable instrument channel must be placed in the trip condition within the Completion Time. Transition into a MODE or other specified condition in the Applicability may be made in accordance with LCO 3.0.4 and the channel is subsequently placed in the tripped condition within the Completion Time, which begins when the Applicability is entered. If the instrument channel cannot be placed in the tripped condition and the subsequent default ACTION ("Required Action and associated Completion Time not met") allows the OPERABLE train to be placed in operation, use of LCO 3.0.4.a is acceptable because the subsequent ACTIONS to be entered following entry into the MODE include ACTIONS (place the OPERABLE train in operation) that permit safe plant operation for an unlimited period of time in the MODE or other specified condition to be entered.

LCO 3.0.4.b allows entry into a MODE or other specified condition in the Applicability with the LCO not met after performance of a risk assessment addressing inoperable systems and components. consideration of the results, determination of the acceptability of entering the MODE or other

INSERT for LCO 3.0.4 BASES (continued) specified condition in the Applicability. and establishment of risk management actions. if appropriate.

The risk assessment may use quantitative. qualitative. or blended approaches. and the risk assessment will be conducted using the plant program. procedures. and criteria in place to implement 10 CFR 50.65(a)(4). which requires that risk impacts of maintenance activities to be assessed and managed. The risk assessment. for the purposes of LCO 3.0.4.b. must take into account all inoperable Technical Specification equipment regardless of whether the equipment is included in the normal 10 CFR 50.65(a)( 4) risk assessment scope. The risk assessments will be conducted using the procedures and guidance endorsed by Regulatory Guide 1.160. "Monitoring the Effectiveness of Maintenance at Nuclear Power Plants." Regulatory Guide 1.160 endorses the guidance in Section 11 of NUMARC 93-01. "Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants." These documents address general guidance for conduct of the risk assessment.

quantitative and qualitative guidelines for establishing risk management actions. and example risk management actions. These include actions to plan and conduct other activities in a manner that controls overall risk.

increased risk awareness by shift and management personnel. actions to reduce the duration of the condition. actions to minimize the magnitude of risk increases (establishment of backup success paths or compensatory measures). and determination that the proposed MODE change is acceptable. Consideration should also be given to the probability of completing restoration such that the requirements of the LCO would be met prior to the expiration of ACTIONS Completion Times that would require exiting the Applicability.

LCO 3.0.4.b may be used with single. or multiple systems and components unavailable. NUMARC 93-01 provides guidance relative to consideration of simultaneous unavailability of multiple systems and components.

The results of the risk assessment shall be considered in determining the acceptability of entering the MODE or other specified condition in the Applicability. and any corresponding risk management actions. The LCO 3.0.4.b risk assessments do not have to be documented.

The Technical Specifications allow continued operation with equipment unavailable in MODE 1 for the duration of the Completion Time. Since this is allowable. and since in general the risk impact in that particular MODE bounds the risk of transitioning into and through the applicable MODES or other specified conditions in the Applicability of the LCO. the use of the LCO 3.0.4.b allowance should be generally acceptable. as long as the risk is assessed and managed as stated above. However. there is a small subset of systems and components that have been determined to be more important to risk and use of the LCO 3.0.4.b allowance is prohibited. The LCOs governing these systems and components contain

INSERT for LCO 3.0.4 BASES (continued)

Notes prohibiting the use of LCO 3.0.4.b by stating that LCO 3.0.4.b is not applicable.

LCO 3.0.4.c allows entry into a MODE or other specified condition in the Applicability with the LCO not met based on a Note in the Specification which states LCO 3.0.4.c is applicable. These specific allowances permit entry into MODES or other specified conditions in the Applicability when the associated ACTIONS to be entered do not provide for continued operation for an unlimited period of time and a risk assessment has not been performed. This allowance may apply to all the ACTIONS or to a specific Required Action of a Specification. The risk assessments performed to justify the use of LCO 3.0.4.b usually only consider systems and components. For this reason. LCO 3.0.4.c is typically applied to Specifications which describe values and parameters (e.g.* RCS Specific Activity). and may be applied to other Specifications based on NRC plant specific approval.

The provisions of this Specification should not be interpreted as endorsing the failure to exercise the good practice of restoring systems or components to OPERABLE status before entering an associated MODE or other specified condition in the Applicability.

The provisions of LCO 3.0.4 shall not prevent changes in MODES or other specified conditions in the Applicability that are required to comply with ACTIONS. In addition, the provisions of LCO 3.0.4 shall not prevent changes in MODES or other specified conditions in the Applicability that results result from any unit shutdown. In this context. a unit shutdown is defined as a change in MODE or other specified condition in the Applicability associated with transitioning from MODE 1 to MODE 2.

MODE 2 to MODE 3. MODE 3 to MODE 4. and MODE 4 to MODE 5.

Upon entry into a MODE or other specified condition in the Applicability with the LCO not met. LCO 3.0.1 and LCO 3.0.2 require entry into the applicable Conditions and Required Actions until the Condition is resolved. until the LCO is met. or until the unit is not within the Applicability of the Technical Specification.

Exceptions to LCO 3.0.4 are stated in the individual Specifications.

These exceptions allow entry into MODES or other specified conditions in the Applicability 1,vhen the associated ACTIONS to be entered do not provide for continued operation for an unlimited period of time. Exceptions may apply to all the ACTIONS or to a specific Required Action of a Specification.

LCO 3.0.4 is only applicable when entering MODE 4 from MODE 5, MODE 3 from MODE 4 or 5, MODE 2 from MODE 3 or 4 or 5, or MODE 1 from MODE 2. Furthermore, LCO 3.0.4 is applicable when entering any other specified condition in the Applicability only 1,¥hile operating in MODE 1, 2, 3, or 4. The requirements of LCO 3.0.4 do not apply in

INSERT for LCO 3.0.4 BASES (continued)

MODES 5 and 6, or in other specified conditions of the Applicability (unless in MODE 1, 2, 3, or 4) because the ACTIONS of individual Specifications sufficiently define the remedial measures to be taken.

Surveillances do not have to be performed on the associated inoperable equipment (or on variables outside the specified limits), as permitted by SR 3.0.1. Therefore, utilizing changing MODES or other specified conditions while in an ACTIONS Condition, in compliance with LCO 3.0.4 or 1,vhere an m<Geption to LCO 3.0.4 is stated, is not a violation of SR 3.0.1 or SR 3.0.4 for fillYJ hose Surveillances that do not have te-ee not been performed on due to the associated inoperable equipment.

However, SRs must be met to ensure OPERABILITY prior to declaring the associated equipment OPERABLE (or variable within limits) and restoring compliance with the affected LCO.

Technical Specifications Bases BASES LCO Applicability B 3.0 LCO 3.0.4 (continued)

LCO 3.0.5 LCO 3.0.6 VEGP Units 3 and 4 SR a.0.4 ~or U:iose Surveillanees that do not have to be pertorn:ied due to the assooiated inoperable equipn:ient. l=lowe1;er, SRs n:iust be n:iet to ensure OPeRl\\BILITY prior to deolaring the assooiated equipn:ient OPeRl\\BLe (or 1.iariable within lin:iits) and restoring oon:iplianoe with the affeeted LGO.

LCO 3.0.5 establishes the allowance of restoring equipment to service under administrative controls when it has been removed from service or declared inoperable to comply with ACTIONS. The sole purpose of this Specification is to provide an exception to LCO 3.0.2 (e.g., to not comply with the applicable Required Action(s)) to allow the performance of Surveillance Requirements to demonstrate:

a.

The OPERABILITY of the equipment being returned to service; or

b.

The OPERABILITY of other equipment.

The administrative controls ensure the time the equipment is returned to service in conflict with the requirements of the ACTIONS is limited to the time absolutely necessary to perform the required testing to demonstrate OPERABILITY. This specification does not provide time to perform any other preventive or corrective maintenance.

An example of demonstrating the OPERABILITY of the equipment being returned to service is reopening a containment isolation valve that has been closed to comply with Required Actions and must be reopened to perform the SRs.

An example of demonstrating the OPERABILITY of other equipment is taking an inoperable channel or trip system out of the tripped condition to prevent the trip function from occurring during the performance of an SR on another channel in the other trip system. A similar example of demonstrating the OPERABILITY of other equipment is taking an inoperable channel or trip system out of the tripped condition to permit the logic to function and indicate the appropriate response during the performance of an SR on another channel in the same trip system.

LCO 3.0.6 establishes an exception to LCO 3.0.2 for supported systems that have a support system LCO specified in the Technical Specifications (TS). This exception is provided because LCO 3.0.2 would require that the Conditions and Required Actions of the associated inoperable supported system LCO be entered solely due to the inoperability of the support system. This exception is justified because the actions that are B 3.0 - 6 Revision +4

Technical Specifications Bases BASES SR Applicability B 3.0 SR 3.0.3 (continued)

SR 3.0.4 INSERT for SR 3.0.4 BASES When a Section 5.5, "Programs and Manuals," specification states that the provisions of SR 3.0.3 are applicable, it permits the flexibility to defer declaring the testing requirement not met in accordance with SR 3.0.3 when the testing has not been completed within the testing interval (including the allowance of SR 3.0.2 if invoked by the Section 5.5 specification).

SR 3.0.4 establishes the requirement that all applicable SRs must be met before entry into a MODE or other specified condition in the Applicability.

This Specification ensures that system and component OPERABILITY requirements and variable limits are met before entry into MODES or other specified conditions in the Applicability for which these systems and components ensure safe operation of the unit.

i----~~ The prm1isions of this £peoifioation should not be interpreted as endorsing the failure to mEereise the good praetiee of restoring syste1T1s or 001T1ponent to OPeR/\\BU: status before entering an assooiated MODe or other speoified oondition in the Applioability.

Howe>v<er, in eertain eireu1T1stanees, failing to 1T1eet an SR will not result in

£R d.0.4 restrioting a MODe ohange or other speoified oondition ohange.

When a systelTl, subsystelTl, dh1ision, 001T1ponent, de1o1ioe, or 1o1ariable is inoperable or outside its speoified lilTlits, the assooiated £R(s) are not required to be perfor1T1ed, per SR d.0.1, whieh states that suFYeillanees do not ha1o1e to be perfor1T1ed on inoperable equiplTlent. When equiplTlent is inoperable, £R d.0.4 does not apply to the assoeiated £R(s) sinee the require1T1ent for the SR(s) to be perfor1T1ed is relTlo>v<ed. Therefore, failing to perforlTl the £urio1eillanoe(s) within the speoified P:requeno;c does not result in an £R d.0.4 restriotion to ohanging MOD6£ or other speoified eonditions of the Applieability. Howe>o<er, sinee the LGO is not 1T1et in this instanoe, LGO d.0.4 will go1o1ern any restriotions that 1T1ay (or 1T1ay not) apply to MODe or other speoified oondition ohanges.

The pro>o<isions of £R d.0.4 shall not pre>o<ent ehanges in MOD6£ or other speeified eonditions in the Applieability that are required to eolTlply with

/\\GTIO~Jg _ In addition, the pro1o1isions of LGO d.0.4 shall not pre1o1ent ehanges in MOD6£ or other speeified eonditions in the Applieability that result frolTl any unit shutdown.

VEGP Units 3 and 4 B 3.0 - 15 Revision +4

INSERT for SR 3.0.4 BASES The provisions of this Specification should not be interpreted as endorsing the failure to exercise the good practice of restoring systems or component components to OPERABLE status before entering an associated MODE or other specified condition in the Applicability.

A provision is included to allow entry into a MODE or other specified condition in the Applicability when an LCO is not met due to a Surveillance not being met in accordance with LCO 3.0.4.

However, in certain circumstances, failing to meet an SR will not result in SR 3.0.4 restricting a MODE change or other specified condition change.

When a system, subsystem, division, component, device, or variable is inoperable or outside its specified limits, the associated SR(s) are not required to be performed, per SR 3.0.1, which states that surveillances do not have to be performed on inoperable equipment. When equipment is inoperable, SR 3.0.4 does not apply to the associated SR(s) since the requirement for the SR(s) to be performed is removed. Therefore, failing to perform the Surveillance(s) within the specified Frequency does not result in an SR 3.0.4 restriction to changing MODES or other specified conditions of the Applicability. However, since the LCO is not met in this instance, LCO 3.0.4 will govern any restrictions that may (or may not) apply to MODE or other specified condition changes. SR 3.0.4 does not restrict changing MODES or other specified conditions of the Applicability when a Surveillance has not been performed within the specified Frequency, provided the requirement to declare the LCO not met has been delayed in accordance with SR 3.0.3.

The provisions of SR 3.0.4 shall not prevent changes in entry into MODES or other specified conditions in the Applicability that are required to comply with ACTIONS. In addition, the provisions of h-GG--SR 3.0.4 shall not prevent changes in MODES or other specified conditions in the Applicability that result from any unit shutdown. In this context, a unit shutdown is defined as a change in MODE or other specified condition in the Applicability associated with transitioning from MODE 1 to MODE 2, MODE 2 to MODE 3, MODE 3 to MODE 4, and MODE 4 to MODE 5.

The precise requirements for performance of SRs are specified such that exceptions to SR 3.0.4 are not necessary. The specific time frames and conditions necessary for meeting the SRs are specified in the Frequency, in the Surveillance, or both. This allows performance of Surveillances when the prerequisite condition(s) specified in a Surveillance procedure require entry into a-the MODE or other specified condition in the Applicability of the associated LCO prior to the performance or completion of a Surveillance. A Surveillance, that could not be performed until after entering the h-GG--LCO's Applicability, would have its Frequency specified such that it is not "due" until the specific conditions needed are met.

Alternately, the Surveillance may be stated in the form of a Note,. as not required (to be met or performed) until a particular event, condition, or

INSERT for SR 3.0.4 BASES (continued) time has been reached. Further discussion of the specific formats of ~

SRs' annotation is found in Section 1.4, Frequency.

SR 3.0.4 is only applicable when entering MODE 4 from MODE 5, MODE 3 from MODE 4, MODE 2 from MODE 3 or 4, or MODE 1 from MODE 2. Furthermore, SR 3.0.4 is applicable 1,¥hen entering any other specified condition in the Applicability only while operating in MODE 1, 2, 3, or 4. The requirements of SR 3.0.4 do not apply in MODES 5 and 6, or in other specified conditions of the Applicability (unless in MODE 1, 2, 3, or 4) because the ACTIO~JS of individual Specifications sufficiently define the remedial measures to be taken.

BASES SR 3.0.4 (continued)

VEGP Units 3 and 4 Technical Specifications Bases SR Applicability B 3.0 The preeise require1T1ents for perlor1T1anee of SRs are speeified sueh that mcoeptions to SR 3.0.4 are not neoessary. The speoifio tilTle fra1T1es and oonditions neoessary for 1T1eeting the SRs are speoified in the rrequeno;i, in the SuFYeillanoe, or both. This allows perlor1T1anoe of SuFYeillanoes when the prerequisite oondition(s) speoified in a SuFYeillanoe prooedure require entry into a MODe or other speoified oondition in the /\\pplioabilit;i of the assooiated LGO prior to the perlor1T1anoe or 001T1pletion of a Surveillanee. A Surveillanee, that eould not be perlor1T1ed until after entering the LGO /\\pplioabilit;i, would ha*;e its rrequeno;i speoified suoh that it is not "due" until the speoifio oonditions needed are IT'IOt.

/\\lternatel;i, the Surveillanee 1T1a;' be stated in the forlTl of a ~Joto as not required (to be 1T1et or perlor1T1ed) until a partioular e*;ent, oondition, or ti1T10 has been reaohed. rurther disoussion of the speoifio for1T1ats of SR's annotation is found in Seotion 1.4, rrequeno;i.

B 3.0 - 16 Revision +4

BASES ACTIONS VEGP Units 3 and 4 Technical Specifications Bases PAM Instrumentation B 3.3.17 a Note that The ACTIONS Table has been modified by two ~dotes. The first ~Joto mceludes the MODE: ehange restrietion of LGO a.0.1. This mceeption allows entry into an applioable MODe while relying on the l\\GTIONS 01o1en though the l\\GTIO~JS may 01o1entually require a plant shutdown. This mcoeption is aooeptable due to the passi1o10 funotion of the instrun=ients, the operator's ability to respond to an aooident using alternate instrun=ients and methods, and low probability of an 01o1ent requiring these instrun=ients.

The seeond ~Joto in the l',GTIO~JS clarifies the application of Completion Time rules. The Conditions of this Specification may be entered independently for each Function listed on Table 3.3.17-1. The Completion Time(s) of the inoperable channel(s) of a Function will be tracked separately for each Function starting from the time the Condition was entered for that function.

A.1 When one or more Functions have one required channel which is inoperable, the required inoperable channel must be restored to OPERABLE status within 30 days. The 30 day Completion Time is based on operating experience and takes into account the remaining OPERABLE channel (or in the case of a Function that has only one required channel, other non-Regulatory Guide 1.97 instrument channels to monitor the Function), the passive nature of the instrument (no critical automatic action is assumed to occur from these instruments), and the low probability of an event requiring PAM instrumentation during this interval.

B.1 The Required Action directs actions to be taken in accordance with Specification 5.6.5 immediately. Each time an inoperable channel has not met Required Action A.1, and the associated Completion Time has expired, Condition B is entered.

C.1 When one or more Functions have two required channels which are inoperable, (two channels inoperable in the same Function), one channel in the Function should be restored to OPERABLE status within 7 days.

The Completion Time of 7 days is based on the relatively low probability of an event requiring PAM instrument operation and the availability of alternate means to obtain the required information.

B 3.3.17 - 8 Revision +4

BASES LCO (continued)

APPLICABILITY ACTIONS VEGP Units 3 and 4 Technical Specifications Bases RSW B 3.3.18 The RSW covered by this LCO does not need to be energized to be considered OPERABLE. This LCO is intended to ensure the RSW will be OPERABLE if unit conditions require that the RSW be placed in operation.

The RSW LCO is applicable in MODES 1, 2, and 3 and in MODE 4 with Tavg ~ 350°F. This is required so that the facility can be placed and maintained in MODE 4 for an extended period of time from a location other than the control room.

This LCO is not applicable in MODE 4 with Tavg < 350°F or in MODE 5 or 6. In these MODES, the unit is already subcritical and in a condition of reduced Reactor Coolant System (RCS) energy. Under these conditions, considerable time is available to restore necessary instrument control functions if control room instruments or controls become unavailable.

A.1 Condition A addresses the situation where the RSW is inoperable. The Required Action is to restore the RSW to OPERABLE status within 30 days. The Completion Time is based on operating experience and the low probability of an event that would require evacuation of the control room.

B.1 and B.2 If the Required Action and associated Completion Time of Condition A is not met, the unit must be brought to a MODE in which the LCO does not apply. To achieve this status, the unit must be brought to at least MODE 3 within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and to MODE 4 with Tavg < 350°F within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

The allowed Completion Times are reasonable, based on operating experience, to reach the required unit conditions from full power conditions in an orderly manner and without challenging unit systems.

B 3.3.18 - 2 Revision 4e

Technical Specifications Bases BASES RCS Leakage Detection Instrumentation B 3.4.9 APPLICABILITY (continued)

ACTIONS VEGP Units 3 and 4 IRWST gutter drain isolation for testing or maintenance (during which closure of valves PXS-PL-130A/B redirects potential LEAKAGE to the IRWST) and containment purge operations during which none of the RCS LEAKAGE detection instrumentation is required to be OPERABLE.

As provided by Note 1, when plant evolutions that affect the RCS LEAKAGE detection instrumentation occur, the instrumentation is not required to be OPERABLE as long as the RCS water inventory balance prescribed in SR 3.4.7.1 of LCO 3.4.7, "RCS Operational LEAKAGE," is performed once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months after 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months of steady state operation (stable RCS pressure, temperature, power level, pressurizer level, and reactor coolant drain tank (RCDT) and IRWST levels). The 12 hour1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months allowance provides sufficient time to collect and process all necessary data after stable plant conditions are established. The 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months Frequency required by Applicability Note 1 also applies during a 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months normalization period following the reopening of the IRWST gutter drain isolation valves and after closure of the containment purge flow path.

Applicability Note 2 states that the containment atmosphere F18 particulate radioactivity LEAKAGE measurement during MODE 1 is only required when THERMAL POWER is > 20% RTP.

A.1 With one of the two required containment sump level channels inoperable, the one remaining required OPERABLE channel is sufficient for RCS leakage monitoring since the containment radiation provides a method to monitor RCS leakage. The remaining required OPERABLE containment sump level monitor is adequate for steam line leakage monitoring. The containment sump level instruments are capable of detecting a volume change of less than 2 gallons.

Restoration of two containment sump level channels to OPERABLE status is required to regain the function in a Completion Time of 14 days after the monitor's failure. This time is acceptable, considering the frequency of SR 3.4.9.1 and the available required channel.

B 3.4.9 - 4 Revision e4

Technical Specifications Bases BASES RCS Specific Activity B 3.4.10 ACTIONS (continued)

A Note permits the use of the provisions of LCO 3.0.4.c. This allowance permits entry into the applicable MODE(S),

relying on Required Actions A.1 and A.2 while the DOSE EQUIVALENT 1-131 LCO limit is not met.

NUREG

-1431 SURVEILLANCE REQUIREMENTS VEGP Units 3 and 4 The DOSE EQUIVALENT 1-131 must be restored to normal within 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months . If the concentration cannot be restored to within the LCO limit in 48 hours5.555556e-4 days 0.0133 hours 7.936508e-5 weeks 1.8264e-5 months , it is assumed that the LCO violation is not the result of normal iodine spiking.

RS' ~

RS~:rt-t1~""'&-H_...

1e,*~"l'tt!'

. This mEeeptioA is acceptable due to the significant conservatism incorporated int he specific activity limit, the low probability of an event which is limiting due o exceeding this limit, and the ability to restore traAsieAt speei~ie activit excursions while the plant remains at, or proceeds to powe peration.

B.1 linsert comma ~

allowance transient-specific With DOSE EQUIVALENT XE-133 in excess of the allowed limit, the plant must be placed in a MODE or condition in which the LCO requirements are not applicable. This is done by placing the plant in at least MODE 3 with RCS average temperature < S00'F within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

The change to MODE 3 and RCS average temperature< 500°F lowers the saturation pressure of the reactor coolant below the set points of the main steam safety valves, and prevents venting the SG to the environment in a SGTR event. The allowed Completion Time of 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months is reasonable, based on operating experience to reach MODE 3 from full power conditions in an orderly manner, without challenging plant systems.

C.1 If a Required Action and the associated Completion Time of Condition A is not met or if the DOSE EQUIVALENT 1-131 is> 60 µCi/gm, the reactor must be brought to MODE 3 with RCS average temperature< 500°F within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months . The Completion Time of 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months is reasonable, based on operation experience, to reach MODE 3 below 500°F from full power conditions in an orderly manner and without challenging plant systems.

SR 3.4.10.1 SR 3.4.10.1 requires performing a measure of the noble gas specific activity of the reactor coolant at least once every 7 days. This is a quantitative measure of radionuclides with half lives longer than B 3.4.10 - 3 Revision ~

BASES ACTIONS VEGP Units 3 and 4 Technical Specifications Bases

~

INSERT LCO 3.4.14 BASES k!.

A.1 LTOP B 3.4.14 An unisolated accumulator requires isolation within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months . This is only required when the accumulator pressure is at or more than the maximum RCS pressure for the existing temperature allowed by the PIT limit curves.

The Completion Time is based on operating experience that this activity can be accomplished in this time period and on engineering evaluations indicating that an event requiring LTOP is not likely in the allowed time.

B.1 CVS makeup line containment isolation valve, CVS-PL-V091, requires closure within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months . Condition B is modified by a Note stating that the Action is only applicable when an RCS vent of~ 4.15 square inches is not established.

The Completion Time is based on operating experience that this activity can be accomplished in this time period and on engineering evaluations indicating that an event requiring LTOP is not likely in the allowed time.

C.1 and C.2 If isolation is needed and cannot be accomplished in 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months , Required Action C.1 and Required Action C.2 provide two options, either of which must be performed in the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . By increasing the RCS temperature to > 275°F, the accumulator pressure cannot exceed the LTOP limits if the accumulators are fully injected. Depressurizing the accumulators below the LTOP limit from the PTLR also gives this protection.

The Completion Times are based on operating experience that these activities can be accomplished in these time periods and on engineering evaluations indicating that an event requiring LTOP is not likely in the allowed times.

B3.4.14-6 Revision +4

INSERT for LCO 3.4.14 BASES A Note prohibits the application of LCO 3.0.4.b to an inoperable L TOP System. Due to the increased risk associated with the L TOP system being inoperable, the provisions of LCO 3.0.4.b, which allow entry into a MODE or other specified condition in the Applicability with the LCO not met after performance of a risk assessment addressing inoperable systems and components, should not be applied in this circumstance.

ATTACHMENT 4 to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b License Amendment Request to Increase Flexibility in Mode Restraints to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Purpose The purpose of this qualitative assessment is to identify any AP1000 systems and components for which the Vogtle Units 3 and 4 Technical Specifications (TS) should preclude the use of Limiting Condition for Operation (LCO) 3.0.4.b (by addition of a Note), due to the potential for the 10 CFR 50.65(a)(4) assessment to not adequately assess risk significant systems or components for transition to a MODE or other specified condition in the Applicability when returning to power.

Only changes to the mode of applicability, or other specified condition in the applicability, when returning to power are considered as LCO 3.0.4 is not applicable to changes to lower modes that are part of the shutdown of the unit.

For context, 10 CFR 50.65(a)(4) assessments, when not precluded, involve the following:

For transition to Modes 1, 2, and 3 or other specified conditions in the Applicability within those Modes, a potential use of LCO 3.0.4.b involves an assessment using the at-power Probabilistic Risk Assessment (PRA) models (internal events, internal flood, fire) in accordance with station procedures, consistent with implementation of 10 CFR 50.65(a)(4) and NUMARC 93-01. The assessment will account for unavailable equipment and plant conditions. If the instantaneous Core Damage Frequency (CDF) is ~ 1 E-3 or instantaneous Large Early Release Frequency (LERF) is ~ 1 E-4, voluntary entry into the configuration is not permitted and the mode change is not allowed. If the instantaneous risk and duration of the condition will result in an Incremental Core Damage Probability (ICDP) ~ 1 E-6 or Incremental Large Early Release Probability (ILERP) ~ 1 E-7, then the mode change is allowed, provided appropriate risk management actions are implemented prior to exceeding the threshold. If the instantaneous risk and duration of the condition will result in an ICDP < 1 E-6 and ILERP < 1 E-7, then the mode change is allowed without the need for risk management actions.

For transition to Modes 4, 5, and 6 or other specified conditions in the Applicability within those Modes, a potential use of LCO 3.0.4.b involves an assessment using the shutdown defense-in-depth tool in accordance with station procedures, consistent with implementation of 10 CFR § 50.65(a)(4) and NU MARC 91-06. The assessment will account for unavailable equipment and plant conditions. If the assessment determines a key safety function (KSF) will have no available defense-in-depth (Red condition),

voluntary entry into the configuration is not permitted and the mode change is not allowed.

If the assessment determines the KSFs have at least one set of structures, systems and components (SSCs), including supports, (Orange or Yellow condition), then the mode change is allowed provided risk is managed with implementation of appropriate contingency actions. If the assessment determines the KSFs have three or more sets of SSCs, including supports, (Green condition) then the mode change is allowed without the need for risk management actions. Station procedures contain guidance to avoid elevated risk when possible (Orange or Yellow condition) and to minimize time at reduced RCS inventory.

1 to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Acronyms ADS ATWS CCF CDF CT CVS DAS DC ESFAS FWS ICDP IDS ILERP IRWST ISLOCA KSF LCO LERF LOCA LPSD LTOP PRA RCS RCP RNS SFS SG SSC TS Automatic Depressurization System Anticipated Transient Without Scram Common Cause Failure Core Damage Frequency Completion Time Chemical and Volume Control System Diverse Actuation System Direct Current Engineered Safety Feature Actuation System Feedwater System Incremental Core Damage Probability Class 1 E DC and UPS System Incremental Large Early Release Probability In-containment Refueling Water Storage Tank Interfacing System Loss Of Coolant Accident Key Safety Function Limiting Condition for Operation Large Early Release Frequency Loss Of Coolant Accident Low-Power Shutdown Low Temperature Overpressure Protection Probabilistic Risk Assessment Reactor Coolant System Reactor Coolant Pump Normal Residual Heat Removal System Spent Fuel Pool Cooling System Steam Generator Structure, System, or Component Technical Specifications 2

to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Approach TSTF-359 revision 9 (ML031190607) included (as Attachment 4) a qualitative assessment identifying equipment required to be available prior to specific mode transitions for the legacy Westinghouse pressurized water reactors. The assessment approach was described as follows:

The risk from at-power operation is well understood and generally associated with the highest level of plant risk, therefore, operation in the lower modes with equipment unavailable should not be more limiting than operation in Mode 1 unless:

There are unique events to the mode of interest, The typical events in the mode of interest have an increased probability of occurrence, or The mode of interest has a reduced mitigation system capability.

For this assessment, it is necessary to understand the key plant changes that occur during the mode changes so it is possible to identify the initiating events that can occur and systems available for event detection, actuation, and mitigation.

Each of the three bulleted considerations above are addressed in the AP1000 probabilistic risk assessment (PRA) developed to support the application for Design Certification (ML042230497),

because it included a low-power and shutdown risk assessment. The assessment of low-power operation encompassed operation when the reactor is in a subcritical state or is in transition between subcriticality and power operation up to 5% of rated power. Therefore, the first approach taken in this qualitative assessment is to use results and insights from the assessment of low-power and shutdown (LPSD) risk to identify any systems or components that are potentially risk significant during shutdown modes (Modes 4, 5, 6), hot standby (Mode 3), or startup (Mode 2).

The second approach taken in this qualitative assessment is to consider key activities occurring during mode changes, initiating events that can occur, and the systems available for event detection, actuation, and mitigation. Based on those details, qualitative assessments are made to determine any prudent limitations on use of LCO 3.0.4.b For the first approach, the process detailed in Figure 1 is followed to review each TS. If the Conditions allow continued operation in the Applicability for an unlimited period of time per LCO 3.0.4.a, or the specification involves values or parameters, LCO 3.0.4.b would not apply; therefore, further review is not necessary. If LCO 3.0.4.b would apply, the next considerations are whether the TS equipment is identified as risk significant based on insights from the LPSD risk assessment and what are the modes and conditions for which the equipment is risk significant based on insights from the LPSD risk assessment. The final consideration is whether the equipment, if inoperable, can be adequately assessed by the applicable method(s) of risk assessment employed for a potential use of LCO 3.0.4.b. If the inoperable equipment's impact would not be adequately assessed, then use of LCO 3.0.4.b will be precluded for the equipment.

3 to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Figure 1 - Assessment Flowchart Conditions allow for continued operation per LCO Yes 3.0.4.a; or Further review is not necessary the spec involves values or parameters No TS on risk significant LPSD No equipment?

Yes Equipment significant for No the modes/conditions in Use of 3.0.4.b is reasonable the TS Applicability?

Yes MR A4 tool(s) is adequate Yes to assess?

No

. C Preclude use of 3.0.4.b

)

4 to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Assessment First Approach:

This approach uses results and insights from the assessment of low-power and shutdown risk included in the AP1000 design certification PRA, referred to hereafter as the LPSD PRA. LPSD PRA results are summarize in VEGP Units 3 and 4 UFSAR Subsections 19.19.1, 19.19.2, and 19.19.3.

The insight that independent component failures are not in dominant cutsets produced by the LPSD PRA (i.e. low risk achievement worth), indicates that no equipment/systems should be required to be available prior to changing modes during plant startup. Conservatively, by review of CCF events appearing in dominant cutsets and having a corresponding high risk achievement worth, the following potentially risk significant components are identified from the LPSD PRA for use in this risk assessment:

ADS stage 4 squib valves IRWST IRWST high pressure (injection) squib valves IRWST low pressure (recirculation) squib valves IRWST tank strainers IRWST recirculation sump strainers Class 1 E DC and UPS System (IDS) batteries IDS inverters Since initiating events during RCS drained conditions (one foot below the vessel flange or lower) contribute approximately 95% of the total shutdown CDF, common cause failure of the above components are significant only for drained conditions. Drained conditions occur in:

Mode 5 with the RCS open (vented) and RCS level at the flange or lower, or Mode 6 with the RCS level at the flange or lower.

Allowance for LCO 3.0.4.b is reasonable for Modes 1, 2, 3, and 4 and for Mode 5 with the RCS pressure boundary intact and pressurizer level ~ 20% because there are no components/systems with a significant contribution to LPSD CDF for those modes/conditions.

For the TS applicable to Modes 5 or 6 and that require operability of IRWST components, ADS stage 4 squib valves, IDS batteries, IDS inverters, or systems that support their operation, the results of the review are summarized:

For the following TS, LCO 3.0.4.a would apply since the associated Required Actions permit continued operation in the Applicability for an unlimited period of time; therefore, further review is not necessary.

o TS 3.3.8 - Engineered Safety Feature Actuation System (ESFAS) Instrumentation o

TS 3.3.14 - ESFAS IRWST and Spent Fuel Pool Level Instrumentation o

TS 3.3.16 - ESFAS Actuation Logic - Shutdown o

TS 3.3.19 - DAS Manual Controls o

TS 3.3.20 - ADS and IRWST Injection Blocking Device o

TS 3.5.7 - IRWST - Shutdown (Mode 5) o TS 3.5.8 - IRWST - Shutdown (Mode 6) o TS 3.8.2 - DC Sources - Shutdown o

TS 3.8.4 - Inverters - Shutdown o

TS 3.8.6 - Distribution Systems - Shutdown 5

to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b TS 3.3.9 - For Mode 5 and Mode 6 with upper internals installed, 2 switch sets are required for ADS Stage 4 Actuation (Manual Initiation) (Table 3.3.9-1 Function 7). For Mode 5, if the required channel(s) is not restored per B.1 within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , then per C.1 condition H is entered. Condition H does not require exiting the Applicability, so LCO 3.0.4.a would apply in Mode 5 and further review is not necessary. For Mode 6 with upper internals installed, if the required channel(s) is not restored per B.1 within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , then per C.1 condition I is entered. Condition I requires exiting the Applicability by initiating action to remove the upper internals. Since the TS Applicability includes a condition for which the equipment is potentially risk significant based on insights from the LPSD risk assessment, the final consideration is whether the inoperable channels can be adequately assessed by the shutdown defense-in-depth risk assessment. ADS stage 4 flow paths are evaluated in the shutdown defense-in-depth risk assessment tool for their role to support IRWST gravity injection. Based on the limited impact of an inoperable switch set, the ability to assess potential reductions in mitigating system capability, and the potential for adequate remaining defense-in-depth, use of LCO 3.0.4.b is reasonable.

TS 3.4.12 - For Mode 5 with RCS pressure boundary intact and pressurizer level ~ 20%,

TS 3.4.12 requires either 3 or 4 flow paths in ADS stage 4, depending on the time the reactor has been subcritical. The LPSD PRA concluded that a very small contribution to shutdown CDF is from the conditions of RCS pressure boundary intact and pressurizer level ~ 20%; therefore, the equipment is not risk significant for the TS 3.4.12 Applicability and use of LCO 3.0.4.b is reasonable.

TS 3.4.13 - For Mode 6 with upper internals in place, Mode 5 with RCS pressure boundary open, and Mode 5 with pressurizer level < 20%, TS 3.4.13 requires either 3 or 4 flow paths in ADS stage 4, depending on the time the reactor has been subcritical. LCO 3.0.4.a could be used to transition into the TS 3.4.13 Applicability with Condition B by completing Required Action B.2, which opens an alternative flow path to ensure sufficient vent area to support IRWST injection. LCO 3.0.4.b could also apply with the intention of restoring the required ADS stage 4 flow path to operable status within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months . The TS Applicability includes modes/conditions for which the equipment is risk significant based on insights from the LPSD risk assessment, so the final consideration is whether inoperable flow paths in ADS stage 4 can be adequately assessed by the shutdown defense-in-depth risk assessment. ADS stage 4 flow paths are evaluated in the shutdown defense-in-depth risk assessment tool for their role to support IRWST gravity injection. Based on the ability to assess reductions in mitigating system capability and the potential for adequate remaining defense-in-depth, use of LCO 3.0.4.b is reasonable.

TS 3.8.7 - For Modes 5 and 6, TS 3.8.7 requires restoring battery parameters to within TS limits. If not met within the specified Completion Time (CT), the battery must be declared inoperable, which is a TS 3.8.2 condition B entry in Modes 5 and 6. TS 3.8.2 allows for continued operation in the TS 3.8.2 Applicability for an unlimited period of time or declaring the required features inoperable. The latter option could involve a use of LCO 3.0.4.b otherwise addressed by this assessment.

Second Approach:

This approach considers key activities occurring during mode changes, initiating events that can occur, and the systems available for event detection, actuation, and mitigation.

Typical key activities in progress for mode transitions when returning to power are as follows:

6 to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Mode 6 to Mode 5 RCS cooling by RNS Install reactor vessel head (Mode 5 is reached when all vessel head closure bolts fully tensioned)

Lower RCS level to drained conditions (one foot below the vessel flange or lower)

Establish low temperature overpressure protection Mode 5 to Mode 4 RCS cooling by RNS (until transition to cooling by steam generators)

Establish intact RCS RCS fill and vent Start RCPs Increase RCS temperature from ~100°F to 350°F (Mode 4 is reached when RCS temperature exceeds 200°F)

Establish pressurizer bubble Increase RCS pressure to> 400 psig Establish RCS cooling to steam generators from feedwater through startup feedwater control valves (at RCS temperature of ~295°F)

Mode 4 to Mode 3 RCS cooling by steam generators Dilute RCS to pre-critical boron condition Increase RCS temperature from 350°F to 557°F (Mode 3 is reached when RCS temperature exceeds 420°F)

Secure low temperature overpressure protection (when cold leg temperatures exceed 275°F)

Increase RCS pressure to ~2235 psig Mode 3 to Mode 2 Close reactor trip breakers Reactor startup (Mode 2 is reached when Keff ~ 0.99)

Increase power to< 5% rated thermal power Mode 2 to Mode 1 Increase reactor power to> 5% rated thermal power (Mode 1)

Transfer from startup feedwater control valves to main feedwater control valves for feedwater flow to steam generators Bring turbine online Increase reactor power to 100% rated thermal power Initiating events to consider are as follows:

Loss of Coolant Accidents (LOCAs): Large and medium LOCAs involve RCS pipe breaks. Small LOCAs involve RCS pipe breaks or stuck open safety valves. LOCAs are likely when the RCS is at normal operating temperature and pressure which occurs in Modes 1, 2, and 3. The frequency of occurrence is expected to be the same for Modes 1, 2, and 3. The RCP seal LOCA event has been eliminated since Vogtle Unite 3 and 4 use sealless reactor coolant pumps.

7 to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Interfacing System LOCA (ISLOCA): ISLOCA involves a failure of the pressure boundary of a system interfacing with the RCS. ISLOCA is of concern in Modes 4, 5, and 6 with RCS cooling by the RNS system.

Loss of Decay Heat Removal: Loss of decay heat removal is applicable to Modes 2-6. Decay heat is removed by the RNS system in Modes 4, 5, & 6. In Mode 4, RCS cooling is transitioned from the RNS system to the FWS system via steam generators.

Loss of Offsite Power: This event is applicable to all modes of operation. Work in the switchyard occurs more often during shutdown modes than in Mode 1. Loss of offsite power frequency may be higher for shutdown modes.

Steam Generator Tube Ruptures: Steam generator tube ruptures are of concern when there is a high pressure difference across the steam generator tubes, which occurs in Modes 1, 2, and 3.

The frequency of occurrence is expected to be the same for each mode.

Secondary Side Breaks: Secondary side breaks are of concern when the secondary side is at normal operating pressure which is in Modes 1, 2, 3, and 4. The frequency of occurrence is expected to be the same for each mode.

Low Temperature Over-pressurization: This event is of concern when RCS cold leg temperature is less than 275°F, which occurs during Modes 4, 5, & 6.

Anticipated Transient Without Scram (A TWS): This event involves a reactor trip demand and failure of control rod insertion. ATWS is only of concern when the reactor is at power.

Rod Withdrawal: Rod withdrawal events can occur when the rods are partially or fully inserted in the core and the reactor trip breakers are closed. This can only occur in Modes 1, 2, and 3. The frequency of occurrence is expected to be the same for each mode.

Boron Dilution: Boron dilution can occur in all modes of operation and results primarily from lower boron concentration makeup from CVS to the RCS. The frequency of occurrence is very low and is expected to be the same for each mode.

Loss of Feedwater: Loss of feedwater (startup feedwater or main feedwater) is applicable to Modes 1, 2, 3, and 4. The frequency of occurrence is expected to be the same for each mode.

Turbine Trip: Turbine trip can only occur at a power level greater than 5% in Mode 1.

Table 1 provides a summary of important reactor coolant system (RCS) parameters for the different mode transitions when returning to power. Table 2 provides the status of systems performing key safety functions for the different mode transitions when returning to power. It is not intended to be a comprehensive list of plant systems and it does not list necessary support systems.

Based on the key activities occurring during mode changes, initiating events that can occur, and the systems available for event detection, actuation, and mitigation, qualitative assessments are made to determine any prudent limitations on use of LCO 3.0.4.b as follows:

8 to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Modes 5 and 6 The events of interest in Mode 5 and 6 are loss of RCS heat removal, loss of RCS inventory, loss of offsite power, and low temperature over-pressurization. On initial entry into Mode 6, the refueling cavity is at the filled level. Later operation in Mode 6 involves lowering RCS level to 1 foot below the reactor vessel flange during installation of the reactor vessel head. On initial entry into Mode 5, RCS level is 1 foot below the reactor vessel flange. Operation in Mode 5 can also involve lowering RCS level to midloop. Loss of RCS heat removal and loss of RCS inventory are of greatest concern during drained conditions (i.e., 1 foot below flange or lower). Loss of RCS heat removal can be mitigated by one of two trains of RNS, gravity injection from RNS, or gravity injection from the IRWST. RCS inventory makeup can be accomplished by CVS, RNS gravity injection, or gravity injection from the IRWST. Based on redundancy and diversity in the AP1000 design, including passive means of event mitigation that do not rely on offsite power, no systems or components are proposed to be precluded from use of LCO 3.0.4.b for Modes 5 and 6 for mitigation of loss of RCS heat removal, loss of RCS inventory, and loss of offsite power. Low temperature over-pressurization is of concern in Mode 6 with the head on and in Mode 5. It is prudent to preclude compromising the integrity of the RCS pressure boundary; therefore, low temperature overpressure protection (L TOP) is proposed to be required for Mode 5 and for Mode 6 when the reactor vessel head is on.

Limitation: LCO 3.0.4.b is proposed to be precluded for TS 3.4.14 (L TOP), as applicable in Modes 5 and 6.

Mode 4 The events of interest in Mode 4 are loss of RCS heat removal, loss of RCS inventory, loss of offsite power, and low temperature over-pressurization. The key activities in Mode 4 are to increase RCS pressure and temperature and to transition RCS cooling from the RNS system to steam generators from the feedwater system. Loss of RCS heat removal can be mitigated by the feedwater system, passive residual heat removal heat exchanger operation, gravity injection from the IRWST, or RNS operation, either in the normal shutdown cooling alignment in the lower part of Mode 4 or taking suction from the IRWST after establishing RCS cooling via steam generators.

RCS inventory makeup can be accomplished by CVS, CMT injection, or gravity injection from the IRWST. Additionally, after establishing RCS cooling via steam generators, RCS inventory makeup can be accomplished from RNS taking suction from the IRWST. Based on redundancy and diversity in the AP1000 design, including passive means of event mitigation that do not require offsite power, no systems or components are proposed to be precluded from use of LCO 3.0.4.b for Mode 4 for mitigation of loss of RCS heat removal, loss of RCS inventory, and loss of offsite power. Low temperature over-pressurization protection is important in the lower end of Mode 4. It is prudent to preclude compromising the integrity of the RCS pressure boundary; therefore, low temperature overpressure protection (L TOP) is proposed to be required for Mode 4.

Limitation: LCO 3.0.4.b is proposed to be precluded for TS 3.4.14 (L TOP), as applicable in Mode 4.

Modes 2 and 3 The events of interest in Modes 2 and 3 are loss of loss of RCS inventory, loss of offsite power, loss of feedwater, SG tube rupture, secondary side breaks, and rod withdrawal events. The key 9

to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b activity in Mode 3 is to increase RCS temperature and pressure to normal operating pressure and temperature. The key activities in Mode 2 are to withdraw shutdown rods and achieve criticality by control rod withdrawal or boron dilution. The likelihood and risk associated with the events of interest in Modes 2 and 3 is the same as or less than for at-power operation. No components or systems are considered more important in Modes 2 and 3 than at full power.

Limitation: None Mode 1 The events of interest for Mode 1 are the same events as for Modes 2 & 3, as well as turbine trip and ATWS. The key activities are to increase reactor power, to transfer from startup feedwater control valves to main feedwater control valves for feedwater flow to steam generators, and to bring the turbine online. Due to these activities, the frequency of loss of feedwater and turbine trip is potentially higher than at full power. A potential use of LCO 3.0.4.b requires an assessment in accordance with station procedures, which require consideration that initiating event frequencies may be higher than during full power operation. The at-power configuration risk management program can numerically account for an increase to the frequency of loss of feedwater and turbine trip. No components or systems are considered more important in the lower portions of Mode 1 than at full power.

Limitation: None Conclusions Using qualitative approaches, this assessment sought to identify any systems/components for which the Vogtle 3 & 4 Technical Specifications should preclude the use of LCO 3.0.4.b, due to the potential for 1 0CFR50.65(a)(4) assessments to not adequately assess risk significant systems/components for mode changes when returning to power.

The first approach involved use of results and insights from the AP1000 PRA developed to support the application for Design Certification. It was noteworthy that the LPSD PRA reflects approximately 95% of the small LPSD CDF is associated with drained conditions (RCS level at 1 foot below flange or lower), which occurs only during Modes 5 and 6. It was also noteworthy that the LPSD PRA reflects individual components are not risk significant during low-power and shutdown conditions. The assessment conservatively identified potentially significant components based on the significance of their common cause failure. TS associated with those components and having Mode 5 or Mode 6 applicability were reviewed. In each case where LCO 3.0.4.b can apply, the shutdown defense-in-depth assessment used to meet 10 CFR § 50.65(a)(4) is adequate for assessment of a potential use of LCO 3.0.4.b. Also, an overall conclusion is the assessments meeting 10 CFR § 50.65(a)(4) are adequate for assessing a potential use of LCO 3.0.4.b.

The second approach involved summarizing key activities occurring during mode changes, initiating events that can occur, and the systems available for event detection, actuation, and mitigation. Those details were then considered in assessments to determine any prudent limitations on use of LCO 3.0.4.b. A single limitation was identified. Use of LCO 3.0.4.b is proposed to be precluded for a transition into the Applicability of TS 3.4.14, which requires one low temperature over-pressure protection method for Mode 4 when any cold leg temperature is

275°F, Mode 5, and Mode 6 when the reactor vessel head is on.

10 to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Table 1-Key Plant Parameters by Mode and Operating State Mode6 Mode6 Modes Modes Modes Mode4 Mode4 Parameter Cavity Flange Midloop Flange RCS RNS SGS Mode3 Mode2 Model Filled Intact Rx Power 0o/oRTP 0o/oRTP 0o/oRTP 0o/oRTP 0o/oRTP 0o/oRTP 0% RTP 0% RTP

S: 5% RTP

> 5% RTP RCS

~100°F

~100°F 100-200°F 200-295°F 295-420°F 557°F 557°F 557°F Temperature RCS Atmosphere Atmosphere Atmosphere Atmosphere

< 400 psig

> 400 psig

> 400 psig 2235 psig 2235 psig 2235 psig Pressure Cavity Full Cavity Full 1 ft below 1 ft below Pressurizer Flange to flange to Pressurizer Pressurizer Pressurizer Pressurizer Pressurizer RCS Level (26ft above to 1 ft below Hot Leg Pressurizer Midscale Midscale Midscale Midscale Midscale Midscale flange)

Flange Midscale Midscale to Full Secondary 0 psig 0 psig 0 psig 0 psig 0 psig 0 psig Normal Normal Normal Normal Pressure Operating Operating Operating Operating 11 to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Table 2 - System Status by Technical Specification Mode System Mode6 Modes Mode4 Mode3 Mode2 Model RCS Makeup and Letdown Standby Standby Standby Standby Standby Standby Reactor Coolant Pumps Not Running As Needed As Needed or Running Running Running Running Reactor Trip Breakers Open Open Open Open or Closed Closed Closed Startup Feedwater Out of Service Out of Service Standby Standby Standby Standby Main Feedwater Out of Service Out of Service Standby or In In Service In Service In Service Service Normal Residual Heat In Service In Service In Service or Standby Standby Standby Removal (RNS)

Standby RCS cooling by Spent Fuel Standby when Not Available Not Available Not Available Not Available Not Available Pool Cooling cavity flooded RNS gravity injection Standby Standby Standby Standby Standby Standby Passive Residual Heat Not Required Standby when Standby Standby Standby Standby Removal (PRHR)

RCS intact Core Makeup Tanks Not Required Standby when Standby Standby Standby Standby RCS intact Accumulators Not Required Not Required Standby for RCS Standby Standby Standby

> 1000 psig IRWST gravity injection Standby Standby Standby Standby Standby Standby Automatic Depressurization Stages 1, Required Open Required Required Required Required Required 2, and 3 Automatic 3 paths required 1 3 paths required Required Required Required Required Depressurization Stage 4 12 to NL-24-0412 Assessment for Precluding Use of LCO 3.0.4.b Table 2 - System Status by Technical Specification Mode System Mode6 Modes Mode4 Mode3 Mode2 Model Passive Containment Standby Standby Standby Standby Standby Standby Cooling Low Temperature In Service2 In Service In Service3 Not Required Not Required Not Required Overpressure Protection Reactor Trip System Required4 or Required4 or Required4 or Automatic and Manual Not Required Not Required Not Required Not Required Required Required Initiation ES FAS Automatic and Required Required Required Required Required Required Manual Initiation Source Range Not Required 4 channels in 4 channels in 4 channels in 4 channels in Not Required service4 service4 service4 service below P-6 Intermediate Range Not Required Not Required Not Required Not Required 4 channels in 4 channels in service service below P-10 Power Range Not Required Not Required Not Required Not Required Required Required DC Sources As Needed5 As Needed5 Required Required Required Required Standby Diesel Generators Available Available Available Available Available Available Notes:

1. With upper internals in place

2. When reactor vessel head is on

3. When any cold leg temperature is~ 275°F

4. With Plant Control System capable of rod withdrawal or one or more rods not fully inserted

5. For support of equipment required to be operable 13

v t e Letter Sequence Request
EPID:L-2024-LLA-0171, (Approved, Closed) EPID:L-2025-LLA-0011, (Approved, Closed)
Initiation Acceptance... Administration Questions 30 September 2025 Answers Results Approval, Approval, Approval, Approval Other: ML25077A233, ML25269A087
MONTHYEAR2025-07-02 [Table View]

NL-24-0412, License Amendment Request to Increase Flexibility in Mode Restraints

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Enclosure:

SUMMARY

3.0 TECHNICAL EVALUATION

4.0 REGULATORY EVALUATION

5.0 ENVIRONMENTAL CONSIDERATION

6.0 REFERENCES

SUMMARY

3.0 TECHNICAL EVALUATION

4.0 REGULATORY EVALUATION

5.0 ENVIRONMENTAL CONSIDERATION

6.0 REFERENCES

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NL-24-0412, License Amendment Request to Increase Flexibility in Mode Restraints

Text

Enclosure:

SUMMARY

3.0 TECHNICAL EVALUATION

4.0 REGULATORY EVALUATION

5.0 ENVIRONMENTAL CONSIDERATION

6.0 REFERENCES

SUMMARY

3.0 TECHNICAL EVALUATION

4.0 REGULATORY EVALUATION

5.0 ENVIRONMENTAL CONSIDERATION

6.0 REFERENCES

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