ML26008A311

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Supplement to License Amendment Request to Revise Technical Specifications to Adopt TSTF-505-A, Revision 2, Provide Risk-Informed Extended Completion Times – RITSTF Initiative 4b
ML26008A311
Person / Time
Site: Wolf Creek 
Issue date: 01/08/2026
From: Bayer R
Wolf Creek
To:
Office of Nuclear Reactor Regulation, Document Control Desk
References
001167
Download: ML26008A311 (0)
v • d • e


Text

P.O. Box 411 l Burlington, KS 66839 l 620-364-8831 Robert J. Bayer Vice President Engineering January 8, 2026 001167 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

References:

1)

Letter 000670, dated December 17, 2024, from M. T. Boyce, WCNOC, to USNRC, License Amendment Request to Revise Technical Specifications to Adopt TSTF-505-A, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b, (ADAMS ML24352A438)

2)

Letter dated April 2, 2025, S. Lee, USNRC, to C. Reasoner, WCNOC, Wolf Creek Generating Station, Unit 1 - Regulatory Audit Plan in Support of License Amendment Requests to Adopt TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times -

RITSTF Initiative 4B, and 10 CFR 50.69 Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors (EPID L-2024-LLA-0170 AND EPID L-2025-LLA-0017), (ADAMS ML25090A217)

3)

Email dated June 12, 2025, from S. Lee, USNRC, to N. Lee, WCNOC, Wolf Creek TSTF-505 audit questions (APLB, EEEB, EICB) dated June 12, 2025 (EPID: L-2024-LLA-0170), (ADAMS ML25163A010)

4)

Email dated June 20, 2025, from S. Lee, USNRC, to N. Lee, WCNOC, Wolf Creek TSTF-505 audit questions (APLC, SCPB) dated June 20, 2025 (EPID: L-2024-LLA-0170), (ADAMS ML25171A175)

5)

Email dated July 18, 2025, from S. Lee, USNRC, to N. Lee, WCNOC, Wolf Creek TSTF-505 Audit Questions (APLA, STSB) Dated July 18, 2025 (EPID: L-2024-LLA-0170), (ADAMS ML25202A063)

6)

Email dated August 22, 2025, from S. Lee, USNRC, to N. Lee, WCNOC, Wolf Creek TSTF-505 audit question (APLC-01 follow up) dated August 22, 2025 (EPID: L-2024-LLA-0170), (ADAMS ML25234A100)

7)

Email dated September 8, 2025, from S. Lee, USNRC, to N. Lee, WCNOC, Wolf Creek TSTF-505 audit question (APLC-01 follow up, correction dated September 8, 2025) (EPID: L-2024-LLA-0170),

(ADAMS ML25252A205)

001167 Page 2 of 3

8) Email dated November 18, 2025, from S. Lee, USNRC, to N. Lee, WCNOC, Wolf Creek TSTF-505 draft audit question response EEEB-01 - staff comments dated November 18, 2025 (EPID: L-2024-LLA-0170), (ADAMS ML253233A156)
9)

Email dated November 20, 2025, from S. Lee, USNRC, to N. Lee, WCNOC, Wolf Creek TSTF-505 draft audit question response EEEB-01 - staff comments dated November 19, 2025 (EPID:L-2024-LLA-0170), (ADAMS ML25324A074)

Subject:

Docket No. 50-482: Supplement to License Amendment Request to Revise Technical Specifications to Adopt TSTF-505-A, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b Commissioners and Staff:

In accordance with the provisions of Section 50.90 of Title 10 of the Code of Federal Regulations (10 CFR), by letter dated December 17, 2024 (Reference 1), Wolf Creek Nuclear Operating Corporation (WCNOC) submitted a license amendment request (LAR) for the Wolf Creek Generating Station (WCGS) to revise Technical Specifications (TS) by allowing the use of Risk-Informed Completion Times per Technical Specification Task Force (TSTF) traveler TSTF-505-A, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b.

By letter dated April 2, 2025 (Reference 2), the Nuclear Regulatory Commission (NRC) scheduled a regulatory audit with WCNOC staff. During the audit process, the NRC issued questions (References 3 through 7) seeking clarification. After reopening of NRC offices following the October 1 to November 12, 2025 U.S. Government shutdown, additional audit question correspondence followed as noted by References 8 and 9. Through the audit process for the mentioned references, the NRC reviewers noted some items were sufficiently addressed, with no further response required on the docket, while others required additional information be provided on the docket.

While the audit is still in process, in the interest of supporting the NRCs review and enhancing schedule efficiency, WCNOC is submitting this voluntary supplement to the original LAR (Reference 1).

The supplement includes the following attachments and enclosure.

Attachment I provides responses to NRC audit questions requiring docketed information.

Attachment II provides proposed TS 3.8.1 changes (Mark-Up) for audit question EEEB-01.

This change replaces the markup for TS 3.8.1 in the original LAR (Reference 1).

Attachment III provides proposed TS 3.8.1 clean pages for audit question EEEB-01. This replaces the clean pages for TS 3.8.1 in the original LAR (Reference 1).

Attachment IV provides proposed TS Bases changes with TS 3.8.1 for audit question EEEB-

01. This replaces the bases changes for TS 3.8.1 in the original LAR (Reference 1).

Enclosure I provides revisions to select pages from the original LAR (Reference 1).

001167 Page 3 of 3 Per Reference 6, dated August 22, 2025, and Reference 7, dated September 8, 2025, WCNOC is performing additional work for open audit item APLC-01. Based on discussions with the NRC and communication from WCNOC contractor support, WCNOC plans to submit probabilistic risk assessment information to the portal in January 2026, accounting for resource availability during the WCGS fall refueling outage. WCNOC acknowledges this may impact the NRCs review timeline and is submitting this supplement now to mitigate potential delays. A follow-up supplement may be provided upon audit completion if needed.

This supplemental information does not alter the conclusions of the No Significant Hazards Consideration provided in Reference 1. In accordance with 10 CFR 50.91, Notice for public comment; State consultation, a copy of this supplement is being provided to the designated Kansas State official.

This letter contains no commitments. If you have any questions concerning this matter, please contact me at (620) 364-4015, or Dustin Hamman at (620) 364-4204.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 8th of January 2026.

Sincerely, Robert J. Bayer RJB/nwl Attachments I: Responses to NRC Audit Questions Requiring Docketed Information II: Proposed Technical Specification 3.8.1 Changes (Mark-Up) for Audit Question EEEB-01 III: Proposed Technical Specification 3.8.1 Clean Pages for Audit Question EEEB-01 IV: Proposed Technical Specification Bases Changes with TS 3.8.1 for Audit Question EEEB-01 Enclosure I: Revisions to select pages from License Amendment Request 000670 cc:

A. N. Agrawal (NRC), w/a, w/e S. S. Lee (NRC), w/a, w/e J. Meinholdt (KDHE), w/a, w/e J. D. Monninger (NRC), w/a, w/e Senior Resident Inspector (NRC), w/a, w/e WCNOC Licensing Correspondence ET 26-001167, w/a, w/e

Attachment I to 001167 Page 1 of 31 Responses to NRC Audit Questions Requiring Docketed Information

Attachment I to 001167 Page 2 of 31 RESPONSES TO NRC AUDIT QUESTIONS REQUIRING DOCKETED INFORMATION NOTE: The U.S. Nuclear Regulatory Commission (NRC) staffs audit questions are in italics throughout this attachment to distinguish from the Wolf Creek Nuclear Operating Corporation (WCNOC) responses for Wolf Creek Generating Station (WCGS).

Attachment I Table of Contents NRC Question APLB-03............................................................................................................. 3 NRC Question APLC-03............................................................................................................ 5 NRC Question APLC-06............................................................................................................ 6 NRC Question EEEB-01............................................................................................................ 7 NRC Question EEEB-02............................................................................................................ 9 NRC Question EEEB-03...........................................................................................................10 NRC Question EEEB-04...........................................................................................................11 NRC Question EICB-01............................................................................................................12 NRC Question STSB-01...........................................................................................................29 NRC Question STSB-02...........................................................................................................30 NRC Question STSB-03...........................................................................................................31

Attachment I to 001167 Page 3 of 31 NRC Question APLB-03 NUREG-1792, Good Practices for Implementing Human Reliability Analysis (HRA)

(ML051160213), recommends that joint human error probability (HEP) values should not be below 1E-5. The licensee stated that the configuration risk management (CRM) probabilistic risk assessment (PRA) model that will be used to support the RICT calculations will apply a 1E-06 minimum joint human failure event probability (MJHEP), and a sensitivity study was performed to characterize the risk impact from applying this MJHEP value.

a) Please provide additional discussion and justification such as the RICT sensitivity study results, to support the conclusion that the MJHEP value has no impact on the remaining technical specification limiting conditions for operation (LCOs) proposed for the RICT application.

b) If, in response to part (a), it cannot be justified that the MJHEP value has no impact on the application, then provide the following:

i.

Confirm that each joint HEP value below 1E-5 includes its own justification that demonstrates the inapplicability of the NUREG-1792 lower value guideline (i.e.,

using such criteria as the dependency factors identified in NUREG-1921 to assess level of dependence). Provide an estimate of the number of these joint HEP values below 1.0E-5, discuss the range of values, and provide at least two different examples where this justification is applied.

ii.

If joint HEP values used is below 1E-5 and cannot be justified, consider adding an implementation item to set these joint HEPs to 1E-5 in the PRA model prior to the implementation of the RICT program.

WNCOC Response Section 6.2 of NUREG-1921 [1] clarifies that the Minimum Joint Human Error Probability (MJHEP) value of 1E-05 from NUREG 1792 is a suggestion and is not necessarily a prescriptive requirement for the PRA. The NUREG also notes that application of a MJHEP value of 1E-05 has led to an improper overestimation of risk impacts in applications such as the Significance Determination Process. EPRI Report 3002003150 [2] also provides support for this conclusion.

Therefore, following a thorough comparison of the results using MJHEP values of 1E-06 and 1E-05, WCNOC concludes that 1E-06 is a justifiable MJHEP value for the WCGS PRA.

The WCGS PRA model contains approximately 15,000 total dependent events, with 1,403 of these dependent events having joint HEPs smaller than 1E-05. Of these dependent events whose HEPs would be impacted by using different MJHEP values, eleven (11) are identified as candidates for improper overestimation of risk impacts when applying a MJHEP of 1E-05 during quantification as opposed to a MJHEP of 1E-06. That is, these are candidates for further review because they are the only dependent events that are sensitive to the MJHEP choice. The remaining 1,392 dependent events were found to have an insignificant contribution to risk, meaning the WCGS PRA model is insensitive to an adjustment of the MJHEP between 1E-06 and 1E-05 for these dependent events. This set of eleven dependent events was reviewed following the process described in EPRI Report 3002003150 [2] to determine which is a more justifiable MJHEP value to use, given the specific accident sequences involved.

All of the reviewed dependent events feature a loss of Service Water (SW) initiating event where operators fail to align standby Service Water pumps to supply flow, and subsequent failure to supply water using Essential Service Water. The dependent events feature several different accident progressions following loss of all SW flow, such as failure to establish secondary side

Attachment I to 001167 Page 4 of 31 heat removal, consequential RCP seal LOCA resulting from failure to trip the reactor coolant pumps, failure to initiate long term cooling using the RHR system, failure to cooldown and depressurize the reactor using available Main or Auxiliary Feedwater pumps, or, given loss of all secondary side heat removal capability, failure to initiate Feed and Bleed.

Three Time Critical Actions (TCA) are present in some of the dependent events; these are actions to:

Align High Pressure Safety Injection (HPSI) to recirculation mode in response to a low-low RWST level signal, Initiate cooldown and depressurization following loss of HPSI and align the RHR system for shutdown cooling.

The dependency levels between the TCAs and preceding and subsequent HFEs in the dependent events were reviewed and determined to be appropriate based on the specific accident sequences. Also note that these TCAs are late-term actions, with significant lead times and prerequisites before they become critical. TCAs are actions that are well-understood to be important by operators, are clearly identified in WCNOC operating procedure (AI 21-016, Operator Time Critical Actions [4]), and are well-trained with monitoring to confirm operators are able to complete them within the specified time frame. In general, their presence in a dependent event would not be expected to require an increased level of dependency and may actually contribute to a lower level of dependency given their higher level of scrutiny by plant operations.

Moreover, each of the reviewed dependent events feature at least one instance where the dependency between actions is assessed at zero dependency, either due to an intervening success, or due to sufficiently long-time separation between the actions and multiple redundant cues. Other dependency and timing overrides were applied to each of these dependent events indicating that they had been reviewed in detail following cutset reviews during the PRA development. Additionally, loss of Service Water scenarios are well-trained by the operators, represent an uncomplicated sequence of events, span a significant time interval (approximately two hours until RWST depletion or until low pressure recirculation is required [3]) and feature multiple opportunities for recovery of equipment or operator failures.

The review of dependent events that result in risk overestimation when applying a MJHEP value of 1E-05 confirmed that a MJHEP value of 1E-06 is the more technically justifiable MJHEP value for the WCGS PRA. Retaining these dependent events with a MJHEP value of 1E-05 in the PRA model cutset results would distort the importance calculations, overestimate risk metrics, and potentially mask valuable risk insights. Therefore, the use of a 1E-06 minimum joint HEP in the WCGS PRA model is more appropriate for risk applications.

References

1. NUREG-1921, EPRI/NRC-RES Fire Human Reliability Analysis Guidelines, July 2012.
2. EPRI 3002003150, A Process for HRA Dependency Analysis and Considerations on Use of Minimum Values for Joint Human Error Probabilities, August 2016.
3. WCNOC-PSA-005, Success Criteria Development, Revision 2.
4. AI 21-016, Operator Time Critical Actions Validation, Revision 25.

Attachment I to 001167 Page 5 of 31 NRC Question APLC-03 of the LAR does not address the incremental risk associated with seismic-induced loss of offsite power (LOOP) that may follow a design basis seismic event. While accident scenarios involving unrecovered LOOP may be partially accounted for in the internal events PRA, demonstrate that the impact of seismic-induced LOOP on the RICT calculations is negligible.

WCNOC Response:

The potential impact of seismic-induced LOOP is explicitly discussed in Section 5.2 of Reference 1 and is summarized here below.

The approach taken in the estimation of the WCGS S-CDF outlined in Reference 1 assumes that the S-CDF can be based on the likelihood that a single seismic-induced failure leads to core damage. This approach implicitly relies on the assumption that seismic-induced failures of similar equipment show a high degree of correlation (i.e., if one SSC fails, all similar SSCs will also fail).

This assumption is conservative, but direct use of this assumption in evaluating the risk increase from out of service equipment could lead to an underestimation of the change in risk. However, if no correlation at all is assumed in the seismic failures, then the seismic risk would be lower than the risk predicted by a model that incorporates a higher level of seismic correlation, but the change in risk using the un-correlated model with a redundant piece of important equipment out of service would be bounded to the level predicted by the correlated model.

In a S-PRA, seismic impacts to similar components (e.g., all the emergency diesel generators) are typically assumed to be correlated unless there are reasons to justify otherwise. Correlation has the effect of introducing common cause impacts. So, if one train of emergency AC power fails seismically, both trains are modeled to fail given the same seismic event. In general, most seismic impacts would effectively be equivalent to Technical Specification loss of function. The assumption of full correlation is less conservative at low g level; for low magnitude earthquakes, a single train seismic-induced failure is more realistic than a fully correlated failure of both trains.

This approach therefore cannot fully capture the added risk increase of a configuration change during a very low magnitude earthquake. On the other hand, the scenarios with very low magnitude seismic events are essentially captured by the internal events risk scenarios. At very low seismic events, the more realistic event is a seismic-induced LOOP. If no other seismic failures are experienced, the additional risk resulting from a seismic induced LOOP can be estimated by simply comparing the Initiating Event Frequency (IEF). The total IEF for a seismic-induced LOOP can be estimated by a simple integration of the plant hazard curve with the generic fragility for LOOP (Am =0.3g, R = 0.3, U = 0.45) from EPRI guidance (Reference 2), resulting in a total IEF of 8.90E-05. This is approximately 0.35% of the total IEF of the internal events LOOP (Reference 3). On this basis, the potentially underestimated risk is judged to be non-significant.

References

1. SAP-SMAN-TM-TM-RA-000002, Revision 1, Seismic Hazard Analysis to Support Wolf Creek RICT LAR.
2. EPRI 3002015993, Loss of Offsite Power Seismic Fragility Guidance, Electric Power Research Institute (EPRI), August 2019.
3. WCNOC-PSA-001, Revision 7, "At-Power Internal Events PRA, Initiating Events Analysis," (archived via Westinghouse document SAP-RAGN-NR-RX-000006, Revision 0).

Attachment I to 001167 Page 6 of 31 NRC Question APLC-06 Include the following in enclosure 4 of the LAR, with appropriate explanation, to support the staffs review of the licensees seismic and high wind penalty factors:

a. Information included in Table 3-1 of the audit document Seismic Hazard Analysis to Support Wolf Creek RICT LAR, or its updated version.

Condensed tables from the audit documents Att1_WCGS HW RICT Pnlty CDF.pdf and Att1_WCGS HW RICT Pnlty LERF.pdf, presented so that the following are clearly included:

Baseline sequence conditional CDF (CCDP) and conditional LERF (CLERP)

Baseline bounding CDF and LERF Relevant values from the high winds model WNCOC Response in the WCNOC license amendment request, Correspondence 000670 (NRC ADAMS ML24352A438), contains a summary table with information discussed in the question. Refer to Table E5 Total Baseline CDF/LERF on page 3 of 3 within Enclosure 5.

References

1. Letter 000670, dated December 17, 2024, from M. T. Boyce, WCNOC, to USNRC, License Amendment Request to Revise Technical Specifications to Adopt TSTF-505-A, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b, (ADAMS ML24352A438).

Attachment I to 001167 Page 7 of 31 NRC Question EEEB-01 License amendment request (LAR) Section 2.3.2, Technical Variations, Item 7 states, in part WCGS RAs [Required Actions] C.3 and C.4 refer to restoring the SBO DGs [station backout diesel generators] to available status. While the TSTF-505-A [Technical Specification Task Force traveler] acceptance criteria does not specifically address availability versus operability, availability is the premise of PRA modeling. Therefore, it is technically justified to apply RICT to these Completion Times for SBO DG unavailability.

However, the proposed RICT for TS 3.8.1, Required Actions C.3 and C.4 appears inconsistent with the requirements of TSTF-505, Revision 2.

As stated in the exclusion criteria listed in TSTF-505, the traveler will only modify Required Actions that specify that a system be restored to OPERABLE status, that require an instrument channel to be placed in trip, or that require isolating an inoperable isolation valve. Accordingly, TSTF-505 does not authorize applying a RICT to a Required Action that specifies that a system be restored to a status other than OPERABLE (e.g., available).

The proposed changes, as currently structured, would apply RICT to Required Actions C.3 and C.4, which specify, in part, that a system (in this case, station blackout diesel generators) be restored to available status. Therefore, it does not meet the criteria of TSTF-505. Please address this variation from the traveler, including the corresponding technical specification Bases and Action Item in Table E1-1.

Original WCNOC Response The last paragraph of the Technical Variation addresses this. The crux of the argument is that "availability" has already been accepted in the CLB with Amendment 234. The differences between the attributes of "operability" versus "availability" do not preclude application of RICT. In fact, "available" is less restrictive than "operable," and "availability" is the premise of the PRA and generally allows for credit in the RICT calculation.

License amendment request (LAR) Section 1.0 indicates that the methodology for using the RICT Program is described in Nuclear Energy Institute (NEI) 06 09-A, Risk Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines, Revision 0, which was approved by the Nuclear Regulatory Commission (NRC) on May 17, 2007.

Adherence to NEI 06-09-A is required by the RICT Program. Section 2.3.1, Process Requirement 11, and Section 3.2.3 of NEI-06-09-A provide the basis of using availability of RICT applications.

In a RMTS program, the conventional Technical Specification definition of equipment operability applies, just as it does under existing Technical Specifications. Thus, equipment operability is applied by station operating staffs to evaluate whether SSC LCOs are met and whether to enter or exit Technical Specifications actions. If a degraded or nonconforming condition existing on a component can be explicitly modeled by the stations PRA, then a situation specific RICT can be calculated.

NRC Response The response to the staffs question is not adequate because TSTF-505 only allows RICT for TS actions to restore TS equipment to OPERABLE status. The SBO DGs are not the TS equipment (not required by the LCO). SBO DG restoration to available status does not meet the LCO requirements whereas the restoration of the DG to OPERABLE status does meet the LCO

Attachment I to 001167 Page 8 of 31 requirements. OPERABLE and available are not the same thing. Revise the LAR to ensure that the RICT can only be applied to restoration of the inoperable DG. That is, remove the RICT from the TS 3.8.1, Required Actions C.3 and C.4, where the LAR has proposed to add it.

(Additional discussion and explanation were provided during an audit call.)

WCNOC Final Response With further understanding of the NRC audit question, a revised version of Technical Specification (TS) 3.8.1 is included with this supplement. The revised version deletes the RICT wording from the SBO related actions C.3 and C.4 for SBO unavailability. In addition to the revised TS, TS bases page 3.8.1-12 was updated to reflect removal of RICT wording from C.3 and C.4. No changes were made to page 3.8.1-13. The page was included to show the continuation of the last sentence from page 3.8.1-12 which states, Utilization of Required Actions C.2 and C.4 are typically applicable 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> after entry into Condition B (i.e., when the extended 14-day Completion Time is utilized). After review of the changes, WCNOC did not locate information requiring update in Table E1-1 for TS Condition 3.8.1.C based on this topic.

For clarity, the SBOs are still used to support the 14-day EDG allowed single train outage time as previously approved by License Amendment 234.

While updating the RICT related wording for TS 3.8.1, per feedback from Operations staff, B.5 was revised into B.5.1 and B.5.2 to make implementation of the RICT front stops more straightforward for the operating crews. B.5.1 is for traditional 72-hour completion time, and B.5.2 is for 14-day allowed outage time. RICT can be applied to either B.5.1 or B.5.2. This clarification allows the operating crews to track planned 72-hr maintenance by entering Action B.5.1 during a traditional 72-hour completion time window separate from tracking situations involving either 14-day emergent maintenance or the once-per-cycle (per train) 14-day planned maintenance allowed outage time. If emergent work is discovered during the 72-hour maintenance window, the station can enter the B.5.2 action for 14-day emergent work. This change only aids with implementation and is still in alignment with the previously approved License Amendment 234 as related to Branch Technical Position 8-8.

A separate mark-up for page 1.3-1 has been included to make a minor administrative correction to the example using LCO 3.8.1. For clarity to readers, the reference using B.2 in the example is being updated to B.3 to match the change made to TS 3.8.1 with License Amendment 234. Based on an observation from the NRC reviewers, a minor grammatical change was incorporated to more closely match the wording in TS 3.8.1.

References

1. License Amendment 234 Safety Evaluation by Letter dated November 4, 2022, Wolf Creek Generating Station, Unit 1 - Issuance of Amendment No. 234 Re: Diesel Generator Completion Time Extension for Technical Specification 3.8.1, AC Sources - Operating (EPID L-2021-LLA-0173), (ADAMS ML22252A151).
2. NUREG-0800 U.S. NRC Standard Review Plan, Branch Technical Position 8-8, Onsite (Emergency Diesel Generators) and Offsite Power Sources Allowed Outage Time Extensions, dated February 2012 (ADAMS ML113640138).

Attachment I to 001167 Page 9 of 31 NRC Question EEEB-02 LAR Enclosure 1, Table E1-1 (page 19 of 33), the design success criteria (DSC) for TS 3.8.1, Condition D - Two offsite circuits inoperable states, One qualified circuit between the offsite transmission network and the onsite 1E AC Electrical Power Distribution System.

With both offsite circuits inoperable, please explain how one inoperable offsite circuit satisfies the DSC.

WCNOC Response The DSC is relative to the offsite circuits. With two offsite circuits inoperable, the offsite circuit DSC is not met. However, as noted in the right-most column, the availability of onsite AC sources will fulfill the credited safety function. This concept has been accepted by numerous prior precedents.

Table E1-1 in LAR Enclosure 1 is amended by stating the design success criteria is one qualified circuit between onsite AC power sources and the onsite 1E AC electrical power system. The excerpt from Table E1-1 is shown below with the change highlighted in yellow below. See also Enclosure I of this document, which shows the revised table entry for TS Condition 3.8.1.D.

TS Condition TS Condition Description SSCs Covered by TS LCO Condition SSCs Modeled in PRA Function Required by TS LCO Condition Design Success Criteria PRA Success Criteria Other Comments 3.8.1.D AC Sources

- Operating

- Two offsite circuits inoperable Two qualified circuits between the offsite transmission network and the onsite Class 1E AC Electrical Power Distribution System Yes Provide power from offsite transmission network to onsite Class 1E buses One qualified circuit between onsite AC power sources the offsite transmission network and the onsite 1E AC Electrical Power Distribution System The 4160V Class 1E Buses are modeled to automatically isolate from offsite power and align to the applicable onsite power (DGs) upon a loss of offsite power.

Emergency Power (DGs),

SBO DG

System, Normal or Alternate Offsite power paths, and Crosstie Power are all credited in model.

With both offsite circuits inoperable, sufficient onsite AC sources are available to maintain the unit in a safe shutdown condition in the event of a design basis accident or transient.

Attachment I to 001167 Page 10 of 31 NRC Question EEEB-03 In the LAR Enclosure 1, Table E1-1, the PRA success criteria for TS 3.8.1.A and 3.8.4.A states, As needed to supply AC [alternating current] power to supported functions and As needed to supply [DC [direct current] power - see Note 1] to supported functions, respectively. However, there is no description of what the PRA success criteria are. Please explain.

Note 1: Original text stated AC power. Based on TS 3.8.4.A, WCNOC believes this is DC power.

WCNOC Response Consistent with the other TS 3.8.1.A Conditions, redundant offsite sources through XNB01 and XNB02 are explicitly modeled, as well as the redundant onsite power sources. The success criteria are consistent with the design success criteria (one qualified circuit). Similarly, for TS 3.8.4.A, redundant DC sources are explicitly modeled and the success criteria are consistent with the design success criteria (one DC electrical power subsystem available).

The PRA success criteria are consistent with the design success criteria.

Table E1-1 in LAR Enclosure 1 is amended to state that the PRA success criteria are the same as the design criteria. See the excerpt from Table E1-1 with the changes to the dispositions for TS 3.8.1.A and TS 3.8.4.A highlighted in yellow below. See also Enclosure I of this document, which shows the revised table entry for TS Condition 3.8.1.A and 3.8.4.A.

TS Condition TS Condition Description SSCs Covered by TS LCO Condition SSCs Modeled in PRA Function Required by TS LCO Condition Design Success Criteria PRA Success Criteria Other Comments 3.8.1.A AC Sources

- Operating

- One offsite circuit inoperable Two qualified circuits between the offsite transmission network and the onsite Class 1E AC Electrical Power Distribution System Yes Provide power from offsite transmission network to onsite Class 1E buses One qualified circuit between the offsite transmission network and the onsite Class 1E AC Electrical Power Distribution System Same as design criteria.

None 3.8.4.A DC Sources

- Operating

- One DC electrical power subsystem inoperable The Train A and Train B DC electrical power subsystems Yes Ensure availability of required DC power to shut down the reactor and maintain it in a safe condition One DC electrical power subsystem available Same as design criteria.

None

Attachment I to 001167 Page 11 of 31 NRC Question EEEB-04 LAR Attachment 1, Section 2.3.1, Administrative Variations, and Section 2.3.2, Technical Variations, describe the variations from TSTF-505. However, these sections do not identify and provide the variation descriptions of the following Wolf Creek technical specifications:

TS 3.8.1, Condition B, Required Action B.2 TS 3.8.1, Condition G, Required Action G.1 TS 3.8.1, Condition H TS 3.8.4 does not include technical specification Conditions and associated Required Actions for battery chargers and batteries TS 3.8.9, Conditions A, E, and F and associated Required Actions Please explain.

WCNOC Response A RICT is not being proposed for TS 3.8.1, Condition B, Required Action B.2.

o Required action B.2 Verify the required Station Blackout (SBOs) DGs are available is a WCGS specific Technical Specification Required Action added by License Amendment No. 234. The Amendment 234 Safety Evaluation was issued on 11/4/2022 and can be found in NRC ADAMS Accession No. ML22252A151.

A RICT is not being proposed for TS 3.8.1, Condition G, Required Action G.1.

A RICT is not being proposed for any Required Action contained in TS 3.8.1 Condition H.

As stated in Attachment IV, TS 3.8.4 describes applying a RICT to RA A.1, and is described as an administrative variation from Standard Technical Specification (STS) 3.8.4, Condition C, RA C.1.

RICTs are not being proposed for any RAs associated with TS 3.8.9 Conditions A, E, or F.

References

1. Letter dated November 4, 2022, from USNRC to C. Reasoner, WCNOC, Wolf Creek Generating Station, Unit 1 - Issuance of Amendment No. 234 RE: Diesel Generator Completion Time Extension for Technical Specification 3.8.1, AC Sources - Operating (EPID L-2021-LLA-0173), ADAMS Accession No. ML22252A151.

Attachment I to 001167 Page 12 of 31 NRC Question EICB-01 TSTF-505 Rev. 2 (ML18183A493) PDF page 113 of 850 states:

The description of proposed changes to the protective instrumentation and control features in TS Section 3.3, "Instrumentation," should confirm that at least one redundant or diverse means (other automatic features or manual action) to accomplish the safety functions (for example, reactor trip, SI [safety injection], containment isolation, etc.)

remains available during use of the RICT, consistent with the defense-in-depth philosophy as specified in RG 1.174. (Note that for each application, the staff may selectively audit the licensing basis of the most risk-significant functions with proposed RICTs to verify that such diverse means exist.)

The LAR (ML24352A438) - See LAR PDF page 194 of 264 (a.k.a. LAR Enclosure 1 page 20 [see Note] of 33) Section 3. Evaluation of Instrumentation and Control - includes an evaluation to address the above; however, this evaluation is missing the table (typically supplied in TSTF-505 applications), which systematically demonstrates, for each event in Chapter 15 (that is mitigated by instrumentation and control (I&C) subject to RICT), the credited means and the diverse means to initiate the protective function. Please provide this table for discussion during the audit.

Note: For clarity, the information is on page 30 of LAR Enclosure 1.

WCNOC Response Below is a table which systematically demonstrates, for each event in Chapter 15 (that is mitigated by instrumentation and control (I&C) subject to RICT), the credited means and the diverse means to initiate the protective function.

RICT Function USAR Chapter 15 Event Diverse Functions Reference RTS Instrumentation (Note 1)

1. Manual Reactor Trip Available for all accidents
  • N/A USAR Table 7.2-4 2.a Power Range Neutron Flux - High Feedwater System Malfunction that Results in a Decrease in Feedwater Temperature
  • Overtemperature T
  • Overpower T
  • SG Water Level -

Low-Low

  • Source Range Neutron Flux -

High

  • Intermediate Range Neutron Flux - High

Attachment I to 001167 Page 13 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference 2.a Power Range Neutron Flux -- High (continued)

Uncontrolled Rod Cluster Control Assembly Bank Withdrawal From a Subcritical or Low Power Startup Condition

  • Power Range Neutron Flux -

Low

  • Intermediate Range Neutron Flux
  • Source Range Neutron Flux
  • Power Range Neutron Flux Rate - High Positive Rate USAR Table 7.2-4 USAR Figure 15.0-16 Uncontrolled Rod Cluster Control Assembly Bank Withdrawal at Power
  • Power Range Neutron Flux Rate - High Positive Rate
  • Overtemperature T
  • Overpower T
  • Pressurizer Pressure - High
  • Pressurizer Water Level -

High

  • Overtemperature T
  • Overpower T
  • Overpower T
  • Overpower T

Attachment I to 001167 Page 14 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference 2.a Power Range Neutron Flux -- High (continued)

Spectrum of Rod Cluster Control Assembly Ejection Accidents

  • Power Range Neutron Flux -

Low

  • Power Range Neutron Flux Rate - High Positive Rate
  • Intermediate Range Neutron Flux
  • Source Range Neutron Flux
  • Power Range Neutron - High
  • Overtemperature T
  • Overpower T
  • High Pressurizer Pressure
  • High Pressurizer Level USAR Figure 15.0-20 2.b Power Range Neutron Flux - Low Uncontrolled Rod Cluster Control Assembly Bank Withdrawal From a Subcritical or Low Power Startup Condition
  • Power Range Neutron Flux -

High

  • Intermediate Range Neutron Flux
  • Source Range Neutron Flux
  • Power Range Neutron Flux Rate - High Positive Rate

Attachment I to 001167 Page 15 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference 2.b Power Range Neutron Flux - Low (continued)

Feedwater System Malfunction that Results in a Decrease in Feedwater Temperature

  • Overtemperature T
  • Overpower T
  • SG Water Level

- Low-Low

  • Source Range Neutron Flux -

High

  • Intermediate Range Neutron Flux - High
  • Power Range Neutron Flux -

High

  • Power Range Neutron Flux Rate - High Positive Rate
  • Intermediate Range Neutron Flux
  • Source Range Neutron Flux
3. Power Range Neutron Flux Rate -

High Positive Rate Spectrum of Rod Cluster Control Assembly Ejection Accidents

  • Power Range Neutron Flux -

High

  • Power Range neutron Flux -

Low

  • Intermediate Range Neutron Flux
  • Source Range Neutron Flux

Attachment I to 001167 Page 16 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference

4. Intermediate Range Neutron Flux Uncontrolled Rod Cluster Control Assembly Bank Withdrawal From a Subcritical or Low Power Startup Condition
  • Power Range Neutron Flux -

High

  • Power Range Neutron Flux -

Low

  • Source Range Neutron Flux
  • Power Range Neutron Flux Rate - High Positive Rate
6. Overtemperature T

Uncontrolled Rod Cluster Control Assembly Bank Withdrawal at Power

  • Power Range Neutron Flux Rate - High Positive Rate
  • Power Range Neutron Flux -

High

  • Overpower T
  • Pressurizer Pressure - High
  • Pressurizer Water Level -

High

  • Power Range Neutron - High
  • Overtemperature T
  • Overpower T
  • High Pressurizer Pressure
  • High Pressurizer Level

Attachment I to 001167 Page 17 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference

6. Overtemperature T

(continued)

Loss of External Electrical Load

  • Pressurizer Pressure - High
  • Pressurizer Water Level -

High

  • Low-Low SG Level
  • Pressurizer Pressure - High
  • Pressurizer Water Level -

High

  • Power Range Neutron Flux -

High

  • Power Range Neutron Flux -

Low

  • Overtemperature T Overpower T
  • SG Water Level

- Low-Low

  • Source Range Neutron Flux -

High

  • Intermediate Range Neutron Flux - High
  • Power Range Neutron Flux -

High

  • Overpower T
  • Pressurizer Pressure - Low

Attachment I to 001167 Page 18 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference

6. Overtemperature T

(continued)

Inadvertent Opening of a Steam Generator Atmospheric Relief or Safety Valve

  • Power Range Neutron Flux -

High

  • Overpower T
  • Pressurizer Pressure - Low
  • Overtemperature T
  • SG Water Level

- Low-Low

7. Overpower T Uncontrolled Rod Cluster Control Assembly Bank Withdrawal at Power
  • Power Range Neutron Flux Rate - High Positive Rate
  • Overtemperature T
  • Power Range Neutron Flux -

High

  • Pressurizer Pressure - High
  • Pressurizer Water Level -

High

Attachment I to 001167 Page 19 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference

7. Overpower T (continued)

Feedwater System Malfunction that Results in a Decrease in Feedwater Temperature

  • Power Range Neutron Flux -

Low

  • Overtemperature T Power Range Neutron Flux - High
  • SG Water Level

- Low-Low

  • Source Range Neutron Flux -

High

  • Intermediate Range Neutron Flux - High
  • Overtemperature T
  • Power Range Nuclear Flux -

High

  • Power Range Neutron Flux -

High

  • Power Range Neutron Flux -

High

  • Power Range Neutron - High
  • Overtemperature T
  • Overpower T
  • High Pressurizer Pressure
  • High Pressurizer Level USAR Figure 15.0-20

Attachment I to 001167 Page 20 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference 8.a Pressurizer Pressure - Low Inadvertent Opening of a Pressurizer Safety or Relief Valve

  • Overtemperature T
  • Overtemperature T
  • Overtemperature T
  • Manual Reactor Trip USAR Table 7.2-4 USAR Figure 15.0-24 8.b Pressurizer Pressure - High Uncontrolled Rod Cluster Control Assembly Bank Withdrawal at Power
  • Power Range Neutron Flux Rate - High Positive Rate
  • Overtemperature T
  • Overpower T
  • Power Range Neutron Flux -

High

  • Pressurizer Water Level -

High

  • Pressurizer Water Level -

High

  • Low-Low SG Level
  • Overtemperature T
  • Pressurizer Water Level -

High

Attachment I to 001167 Page 21 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference 8.b Pressurizer Pressure - High (continued)

CVCS Malfunction that Results in a Decrease in the Boron Concentration in the Reactor Coolant.

  • Power Range Neutron - High
  • Overtemperature T
  • Overpower T
  • High Pressurizer Pressure
  • High Pressurizer Level USAR Figure 15.0-20 Feedwater System Pipe Break
  • Overtemperature T
  • SG Water Level

- Low-Low

9. Pressurizer Water Level - High Uncontrolled Rod Cluster Control Assembly Bank Withdrawal at Power
  • Power Range Neutron Flux Rate - High Positive Rate
  • Overtemperature T
  • Overpower T
  • Power Range Neutron Flux -

High

  • Pressurizer Pressure - High
  • Pressurizer Pressure - High
  • Low-Low SG Level
  • Overtemperature T
  • Pressurizer Pressure - High

Attachment I to 001167 Page 22 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference

9. Pressurizer Water Level - High (continued)

CVCS Malfunction that Results in a Decrease in the Boron Concentration in the Reactor Coolant.

  • Power Range Neutron - High
  • Overtemperature T
  • Overpower T
  • High Pressurizer Pressure
  • High Pressurizer Level USAR Figure 15.0-20
10. Reactor Coolant Flow - Low Partial Loss of Forced Reactor Coolant Flow

Low-Low

12. Undervoltage RCPs Complete Loss of Forced Reactor Coolant Flow
13. Underfrequency RCPs Complete Loss of Forced Reactor Coolant Flow
14. SG Water Level -

Low-Low Loss of Normal Feedwater Flow

  • Overtemperature T

Attachment I to 001167 Page 23 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference

14. SG Water Level -

Low-Low (continued)

Feedwater System Malfunction that Results in a Decrease in Feedwater Temperature

  • Power Range Neutron Flux -

Low

  • Overtemperature T Overpower T
  • Power Range Neutron Flux -

High

  • Source Range Neutron Flux -

High

  • Intermediate Range Neutron Flux - High
  • High Pressurizer Pressure
  • Overtemperature T
  • SG Water Level

- Low-Low

Low Fluid Oil Pressure/Turbine Stop Valve Closure Loss of External Electrical Load

  • Pressurizer Water Level -

High

  • Pressurizer Pressure - High
  • Overtemperature T
  • Low-Low SG Level

Attachment I to 001167 Page 24 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference 16.a/b Turbine Trip -

Low Fluid Oil Pressure/Turbine Stop Valve Closure (continued)

Turbine Trip

  • Overtemperature T
  • Pressurizer Water Level -

High

  • Pressurizer Pressure - High
  • SG Water Level

- Low-Low

17. SI Input from ESFAS Inadvertent Opening of a Steam Generator Atmospheric Relief or Safety Valve
  • Overpower T
  • Power Range neutron Flux -

High

19. Reactor Trip Breakers N/A - This function is a design feature of the RTS system required for operability in support of any trip signal.
  • N/A N/A
20. Reactor Trip Breaker Undervoltage and Shunt Trip Mechanisms N/A - This function is a design feature of the RTS system required for operability in support of any trip signal.
  • N/A N/A
21. Automatic Trip Logic N/A - This function is a design feature of the RTS system required for operability in support of any trip signal.
  • N/A N/A ESFAS Instrumentation (Note 2) 1.a Safety Injection Manual Initiation Available for all accidents where SI is credited.
  • N/A TS Bases B 3.3.2 1.b Safety Injection Automatic Actuation Logic and Actuation Relays Available for all accidents where SI is credited.

Attachment I to 001167 Page 25 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference 1.c Safety Injection Containment Pressure - High 1 Depressurization of Main Steam System

  • Pressurizer Pressure - Low
  • Steam Line Pressure - Low
  • Manual Initiation USAR Figure 15.0-10 Major Rupture of a Main Feedwater Line
  • Steam Line Pressure - Low
  • Manual Initiation USAR Figure 15.0-14 Loss-of-Coolant Accident
  • Pressurizer Pressure - Low
  • Manual Initiation USAR Figure 15.0-25 Rupture of Control Rod Drive Mechanical Housing
  • Containment Pressure - High 3
  • Pressurizer Pressure - Low USAR Figure 15.0-21 1.d Safety Injection Pressurizer Pressure

- Low Depressurization of Main Steam System

  • Containment Pressure High -

1

  • Steam Line Pressure - Low
  • Manual Initiation USAR Figure 15.0-23 SG Tube Rupture
  • Manual Initiation USAR Figure 15.0-24 Loss-of-Coolant Accident
  • Containment Pressure - High 1
  • Manual Initiation USAR Figure 15.0-25 Rupture of Control Rod Drive Mechanical Housing
  • Containment Pressure - High-1, 3
  • Manual Initiation USAR Figure 15.0-21 1.e Safety Injection Steam Line Pressure

- Low Depressurization of Main Steam System

  • Containment Pressure High -

1

  • Pressurizer Pressure - Low
  • Manual Initiation USAR Figure 15.0-10 Major Rupture of a Main Feedwater Line
  • Containment Pressure High -

1

  • Manual Initiation USAR Figure 15.0-14

Attachment I to 001167 Page 26 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference 2.a Containment Spray Manual Initiation Loss-of-Coolant Accident

  • Automatic Actuation Logic and Actuation Relays
  • Containment Pressure High -

3 USAR Figure 15.0-25 2.b Containment Spray Automatic Actuation Logic and Actuation Relays Loss-of-Coolant Accident

  • Containment Pressure High -

3

  • Manual Initiation USAR Figure 15.0-25 3.a/b.(1)

Containment Isolation Phase A/B Isolation - Manual Initiation Loss-of-Coolant Accident

  • Automatic Actuation Logic and Actuation Relays
  • Containment Pressure High -

3 USAR Figure 15.0-25 3.a/b.(2)

Containment Isolation Phase A/B Isolation - Automatic Actuation Logic and Actuation Relays Loss-of-Coolant Accident

  • Manual Initiation USAR Figure 15.0-25 4.a. Steam Line Isolation - Manual Initiation Available for all accidents where Steam Line Isolation is credited.
  • N/A TS Bases B 3.3.2 4.b. Steam Line Isolation - Automatic Actuation Logic and Actuation Relays (SSPS)

Available for all accidents where Steam Line Isolation is credited.

Available for all accidents where Steam Line Isolation is credited.

  • Steam Line Pressure - Low
  • Steam Isolation negative Rate -

High

  • Manual Initiation USAR Figure 15.0-10 4.e.(1) Steam Line Isolation Steam Line Pressure - Low Depressurization of Main Steam System
  • Containment Pressure - High 2
  • Steam Isolation negative Rate -

High

  • Manual Initiation USAR Figure 15.0-10

Attachment I to 001167 Page 27 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference 4.e.(2) Steam Line Isolation Negative Rate - High Depressurization of Main Steam System

  • Steam Line Pressure - Low
  • Containment Pressure - High 2

USAR Figure 15.0-10 5.a Turbine Trip and Feedwater Isolation Automatic Actuation Logic and Actuation Relays (SSPS)

Available for all accidents where Turbine Trip and Feedwater Isolation is credited.

Available for all accidents where Turbine Trip and Feedwater Isolation is credited.

High-High (P-14)

Depressurization of Main Steam System

  • Safety Injection
  • Manual Initiation USAR Figure 15.0-10 6.b Auxiliary Feedwater Automatic Actuation Logic and Actuation Relays (Solid State Protection System)

This is a design feature that is available for all accidents where Auxiliary Feedwater is credited.

This is a design feature that is available for all accidents where Auxiliary Feedwater is credited.

  • Manual Initiation USAR Figure 15.0-13 USAR Section 7.3.6.1.1 Major Rupture of a Main Feedwater Line
  • Manual Initiation USAR Figure 15.0-14 Depressurization of Main Steam System
  • Manual Initiation USAR Figure 15.0-10 Inadvertent ECCS Operation At Power
  • Manual Initiation USAR Figure 15.0-22 Loss of External Electrical Load
  • Manual Initiation USAR Figure 15.0-11

Attachment I to 001167 Page 28 of 31 RICT Function USAR Chapter 15 Event Diverse Functions Reference 6.f Auxiliary Feedwater Loss of Offsite Power Loss of Non-Emergency AC Power to the Station Auxiliaries

  • Low-Low SG Level
  • Low-Low SG Level
  • Manual Initiation USAR Figure 15.0-13 USAR Section 7.3.6.1.1 Major Rupture of a Main Feedwater Line
  • SG Water Level

- Low-Low

Low Available for all accidents where Auxiliary Feedwater is credited.

  • N/A TS Bases B 3.3.2 7.a Automatic Switchover to Containment Sump Automatic Actuation Logic and Actuation Relays Available for all accidents where Automatic Switchover to Containment Sump is credited.
  • N/A TS Bases B 3.3.2 Loss of Power Diesel Generator Start Instrumentation 4-kV NB Bus Loss of Voltage Available for all accidents where DG is credited.
  • N/A TS Bases B 3.3.5 4-kV NB Bus Degraded Voltage Available for all accidents where DG is credited.
1. RICT Function from TS Table 3.3.1-1 in license amendment request dated December 17, 2025, WCNOC Correspondence 000670 (ADAMS ML24352A438).
2. RICT Function from TS Table 3.3.2-1 in license amendment request dated December 17, 2025, WCNOC Correspondence 000670 (ADAMS ML24352A438).

References

1. As provided in Column 4.

Attachment I to 001167 Page 29 of 31 NRC Question STSB-01 of the license amendment request (LAR), Table 1, Page 10 cites technical variation number 5 (TV-5) as the justification for adding a risk-informed completion time (RICT) to limiting condition for operation (LCO) 3.7.5, Action B.1. However, TV-5 does not discuss this action. It discusses LCO 3.7.2 Condition B. Please provide the justification for adding a RICT to LCO 3.7.5, Action B.1.

WCNOC Response WCGS TS 3.7.5 Condition B - One ESW supply to turbine driven AFW pump inoperable. The Condensate Storage Tank (CST) provides a non-safety grade source of water to the steam generators for removing decay and sensible heat from the Reactor Coolant System (RCS). The CST provides a passive flow of water, by gravity, to the auxiliary feedwater (AFW) System.

Although the non-seismically qualified CST is the preferred source of low conductivity water for the AFW pumps, the safety related and seismically qualified water source that is required to be available to support operability of the AFW pumps is the Essential Service Water (ESW) System.

Each independent train of ESW supplies one motor driven AFW pump, and both trains of ESW supply the turbine driven AFW pump. One inoperable ESW supply line in the turbine driven AFW train does not render the turbine driven AFW pump inoperable, since the turbine driven AFW train is provided with redundant ESW supply lines. Since Condition B does not result in a loss of function, it is acceptable to add an RICT to RA B.1, Restore ESW supply to OPERABLE status.

WCGS TS 3.7.5 Condition B One ESW supply to turbine driven AFW pump inoperable was approved by License Amendment 225 (Reference 2). The 72-hour completion time allows the ESW supply to be removed from service while the turbine driven AFW pump remains operable.

This allowed time supports flushing of the ESW piping - which carries lake water from the ultimate heat sink - to remove sediment and control organic growth (Reference 1).

References

1. Letter 19-0033 dated August 29, 2019, from J. McCoy, WCNOC, to USNRC, License Amendment Request for Revision to Technical Specification 3.7.5, "Auxiliary Feedwater (AFW) System", ADAMS ML19247C062.
2. Letter dated August 25, 2020, from S. Lee, USNRC, to C. Reasoner, WCNOC, Wolf Creek Generating Station, Unit 1 - Issuance of Amendment No. 225 Re: Revision to Technical Specification 3.7.5, "Auxiliary Feedwater (AFW) System" (EPID L-2019-LLA-0196),

ADAMS ML20205L304.

Attachment I to 001167 Page 30 of 31 NRC Question STSB-02 Technical variation number 4 (TV-4) provides the technical justification for adding a RICT to TS 3.7.2, Condition A. The second to last sentence states, Therefore, two independent MSIV actuation trains are required to be operable in Modes 1, 2, and 3 to satisfy TS LCO 3.7.4.

[Emphasis added.] Please confirm that the sentence should refer to LCO 3.7.2 and not LCO 3.7.4 or provide an explanation of the connection to LCO 3.7.4.

WCNOC Response WCNOC confirms that TV-4 should only refer to TS LCO 3.7.2.

Technical Variation 4 from page 8 of Attachment I to 000670 is reproduced below with the correction.

4. WCGS TS 3.7.2, Condition A, One MSIV actuator train inoperable. The main steam isolation valve (MSIV) actuators (skid-mounted at the valve) consist of two separate system-medium actuation trains. In the event of a single failure that prevents one entire MSIV actuation train from performing its required function, safety function is preserved by the other operable MSIV actuation train. Therefore, two independent MSIV actuation trains are required to be operable in Modes 1, 2, and 3 to satisfy TS LCO 3.7.4 3.7.2. Since Condition A does not result in a loss of function, it is acceptable to add an RICT to RA A.1, Restore MSIV actuator train to OPERABLE status.

Attachment I to 001167 Page 31 of 31 NRC Question STSB-03 What does administrative variation number 6 (AV-6) apply to? A text search did not reveal where it was referenced in the LAR.

WCNOC Response WCNOC confirms that AV-6 was not invoked in Attachment IV. The original page 4 of Attachment I to 000670, with administrative variation number 6 listed, has been revised by showing the original wording crossed out and adding a note stating not used. The marked-up page is included within Enclosure I of this license amendment request supplement.

Attachment II to 001167 Page 1 of 10 Proposed Technical Specification 3.8.1 Changes (Mark-Up) for Audit Question EEEB-01 Notes:

1. Includes page 1.3-1 with historical editorial correction.
2. Does not include pages where only pagination was impacted. The entire Section 3.8 will be impacted by pagination changes due to page shifting from the LCO 3.8.1 related updates.

Completion Times 1.3 Wolf Creek - Unit 1 1.3-1 Amendment No. 123, 222 1.0 USE AND APPLICATION 1.3 Completion Times PURPOSE The purpose of this section is to establish the Completion Time convention and to provide guidance for its use.

BACKGROUND Limiting Conditions for Operation (LCOs) specify minimum requirements for ensuring safe operation of the unit. The ACTIONS associated with an LCO state Conditions that typically describe the ways in which the requirements of the LCO can fail to be met. Specified with each stated Condition are Required Action(s) and Completion Time(s).

DESCRIPTION The Completion Time is the amount of time allowed for completing a Required Action. It is referenced to the discovery of a situation (e.g.,

inoperable equipment or variable not within limits) that requires entering an ACTIONS Condition unless otherwise specified, providing the unit is in a MODE or specified condition stated in the Applicability of the LCO.

Unless otherwise specified, the Completion Time begins when a senior licensed operator on the operating shift crew with responsibility for plant operations makes the determination that an LCO is not met and an ACTIONS Condition is entered. The otherwise specified exceptions are varied, such as a Required Action Note or Surveillance Requirement Note that provides an alternative time to perform specific tasks, such as testing, without starting the Completion Time. While utilizing the Note, should a Condition be applicable for any reason not addressed by the Note, the Completion Time begins. Should the time allowance in the Note be exceeded, the Completion Time begins at that point. The exceptions may also be incorporated into the Completion Time. For example, LCO 3.8.1, AC Sources - Operating, Required Action B.2, requires declaring required feature(s) supported by an inoperable diesel generator, inoperable when the redundant required feature(s) are inoperable. The Completion Time states, 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> from discovery of Condition B concurrent with inoperability of redundant required feature(s). In this case the Completion Time does not begin until the conditions in the Completion Time are satisfied.

Required Actions must be completed prior to the expiration of the specified Completion Time. An ACTIONS Condition remains in effect and the Required Actions apply until the Condition no longer exists or the unit is not within the LCO Applicability.

If situations are discovered that require entry into more than one Condition at a time within a single LCO (multiple Conditions), the Required Actions for each Condition must be performed within the associated Completion Time. When in multiple Conditions, separate Completion Times are tracked for each Condition starting from the discovery of the situation that (continued)

B.3 (This page is fixing a historical editorial issue when LA 234 was implemented.)

its is

AC Sources -Operating 3.8.1

\__/*

3.8 ELECTRICAL POWER SYSTEMS 3.8_'.1.. AC: Sources Operating u

LCO 3.8.1.

  • . The following AC *electrical sources shall be OPERABLE:
  • * -. a.

Two qualified circuits between the offsite transmission network and the onsite Clas<< 1 E AC Electrical Power Distribution System; and

  • . b.

Two diesel generators (DGs) capable of supplying the onsite Class 1 E power distribution subsystem(s); and c.

Load shedder a*nd. emergency lo.ad sequencers for Train.. A and Train B.

APPLICABILITY:

MODES 1, 2, 3, and 4.

ACTIONS

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

LCO 3.0.4b. is not applicable to DGs.

CONDITION A.

One offsite circuit inoperable.

Wolf Creek - Unit 1 REQUIRED ACTION COMPLETION TIME A.1

AND A:2 :*.

---NOTE--

- In MODES 1, 2, and 3, the

.. ¬ -. * *turbine driven auxiliary

    • considered a required redundant feature.

Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter (continued) 3.8-1 Amendment No.. 155..

No change. This page is for information only.

ACTIONS (continued)

CONDITION A.

(continued)

AND A.3 B.

One DG inoperable.

B.1 AND B.2 AND Wolf Creek - Unit 1 REQUIRED ACTION Declare required feature(s) with no offsite power available inoperable when its redundant required feature(s) is inoperable.

Restore offsite circuit to OPERABLE status.

Perform SR 3.8.1.1 for the offsite circuit(s).

Verify the required Station Blackout (SBO) DGs are available.

AC Sources-Operating 3.8.1 COMPLETION TIME 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from discovery of no offsite power to one train concurrent with inoperability of redundant required feature(s) 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> AND 17 days from discovery of failure to meet LCO 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> AND Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> AND Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter (continued) 3.8-2 Amendment No. 123, 163, 234 Insert RICT

INSERT RICT OR In accordance with the Risk Informed Completion Time Program

ACTIONS (continued)

CONDITION B.

(continued)

B.3 AND B.4.1 OR B.4.2 AND Wolf Creek - Unit 1 REQUIRED ACTION NOTE-------------

In MODES 1, 2, and 3, the turbine driven auxiliary feedwater pump is considered a required redundant feature.

Declare required feature(s) supported by the inoperable DG inoperable when its required redundant feature(s) is inoperable.

Determine OPERABLE DG is not inoperable due to common cause failure.

NOTE The Required Action of B.4.2 is satisfied by the automatic start and sequence loading of the DG.

Perform SR 3.8.1.2 for OPERABLE DG.

AC Sources - Operating 3.8.1 COMPLETION TIME 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> from discovery of Condition B concurrent with inoperability of redundant required feature(s) 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 24 hours

( continued) 3.8-3 Amendment No. 123, 163, 234 No change. This page is for information only.

ACTIONS (continued)

CONDITION REQUIRED ACTION B.

(continued)

B.5 Restore DG to OPERABLE status.

c.

Required Action B.2 and C.1 Restore DG to associated Completion OPERABLE status.

Time not met.

OR C.2 Restore DG to OPERABLE status.

OR C.3 Restore required SBO DGs to available status.

OR C.4 Restore required SBO DGs to available status.

Wolf Creek - Unit 1 3.8-4 AC Sources - Operating 3.8.1 COMPLETION TIME 14 days AND 17 days from discovery of failure to meet LCO 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> from Condition B entry NOTE--------

Only allowed once within any given extended DG Completion Time.

24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from Condition C entry 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> from Condition B entry

NOTE------

Only allowed once within any given extended DG Completion Time.

24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from Condition C entry (continued)

Amendment No. 123, 163, 234 Insert RICT Insert 3.8-4a Delete period Delete period Insert RICT Insert RICT

ACTIONS (continued)

CONDITION REQUIRED ACTION B.

(continued)

COMPLETION TIME B.5.1 Restore DG to OPERABLE status.

OR B.5.2 -------------NOTE-------------

Only applicable to planned maintenance once per cycle, per train, or unplanned corrective maintenance.

Restore DG to OPERABLE status.

72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> OR In accordance with the Risk Informed Completion Time Program 14 days OR In accordance with the Risk Informed Completion Time Program 3.8-4a INSERT

ACTIONS (continued)

CONDITION D

Two offsite circuits inoperable.

E.

One offsite circuit inoperable.

AND One DG inoperable.

F.

Two DGs inoperable.

Wolf Creek - Unit 1 REQUIRED ACTION D.1

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

In MODES 1, 2, and 3, the turbine driven auxiliary f eedwater pump is considered a required redundant feature.

Declare required feature(s) inoperable when its redundant required feature(s) is inoperable.

AND D.2 Restore one offsite circuit to OPERABLE status.

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

Enter applicable Conditions and Required Actions of LCO 3.8.9, "Distribution Systems - Operating,"

when Condition E is entered with no AC power source to any train.

E.1 Restore off site circuit to OPERABLE status.

OR E.2 Restore DG to OPERABLE status.

F.1 Restore one DG to OPERABLE status.

AC Sources - Operating 3.8.1 COMPLETION TIME 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> from discovery of Condition D concurrent with inoperability of redundant reo uired features 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 12 hours 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 2 hours (continued) 3.8-5 Amendment No. 2a, 163 Insert RICT Insert RICT

ACTIONS (continued)

CONDITION G.

One load shedder and emergency load sequencer inoperable.

H.

Required Action and associated Completion Time of Condition A, C, D, E, F, or G not met.

OR Required Actions B.1, 8.3, 8.4.1, 8.4.2, and 8.5 and associated Completion Time not met.

I.

Three or more required AC sources inoperable.

Wolf Creek - Unit 1 G.1 AND G.2 H.1 AND H.2 1.1 REQUIRED ACTION Declare affected DG and offsite circuit inoperable.

Restore load shedder and emergency load sequencer to OPERABLE status.

Be in MODE 3.

Be in MODE 5.

Enter LCO 3.0.3.

AC Sources - Operating 3.8.1 COMPLETION TIME Immediately 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 6 hours 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> Immediately 3.8-6 Amendment No. 123, 163, 234 Insert RICT B.5.1, and B.5.2

Attachment III to 001167 Page 1 of 8 Proposed Technical Specification 3.8.1 Clean Pages for Audit Question EEEB-01 Notes:

1. Includes page 1.3-1 with historical editorial correction.
2. Does not include pages where only pagination was impacted. The entire Section 3.8 will be impacted by pagination changes due to page shifting from the LCO 3.8.1 related updates.

Completion Times 1.3 Wolf Creek - Unit 1 1.3-1 Amendment No. 123, 222, TBD 1.0 USE AND APPLICATION 1.3 Completion Times PURPOSE The purpose of this section is to establish the Completion Time convention and to provide guidance for its use.

BACKGROUND Limiting Conditions for Operation (LCOs) specify minimum requirements for ensuring safe operation of the unit. The ACTIONS associated with an LCO state Conditions that typically describe the ways in which the requirements of the LCO can fail to be met. Specified with each stated Condition are Required Action(s) and Completion Time(s).

DESCRIPTION The Completion Time is the amount of time allowed for completing a Required Action. It is referenced to the discovery of a situation (e.g.,

inoperable equipment or variable not within limits) that requires entering an ACTIONS Condition unless otherwise specified, providing the unit is in a MODE or specified condition stated in the Applicability of the LCO.

Unless otherwise specified, the Completion Time begins when a senior licensed operator on the operating shift crew with responsibility for plant operations makes the determination that an LCO is not met and an ACTIONS Condition is entered. The otherwise specified exceptions are varied, such as a Required Action Note or Surveillance Requirement Note that provides an alternative time to perform specific tasks, such as testing, without starting the Completion Time. While utilizing the Note, should a Condition be applicable for any reason not addressed by the Note, the Completion Time begins. Should the time allowance in the Note be exceeded, the Completion Time begins at that point. The exceptions may also be incorporated into the Completion Time. For example, LCO 3.8.1, AC Sources - Operating, Required Action B.3, requires declaring required feature(s) supported by an inoperable diesel generator, inoperable when its redundant required feature(s) is inoperable. The Completion Time states, 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> from discovery of Condition B concurrent with inoperability of redundant required feature(s). In this case the Completion Time does not begin until the conditions in the Completion Time are satisfied.

Required Actions must be completed prior to the expiration of the specified Completion Time. An ACTIONS Condition remains in effect and the Required Actions apply until the Condition no longer exists or the unit is not within the LCO Applicability.

If situations are discovered that require entry into more than one Condition at a time within a single LCO (multiple Conditions), the Required Actions for each Condition must be performed within the associated Completion Time. When in multiple Conditions, separate Completion Times are tracked for each Condition starting from the discovery of the situation that (continued)

AC Sources - Operating 3.8.1 Wolf Creek - Unit 1 3.8-2 Amendment No. 123, 163, 234, TBD ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME A.

(continued)

Declare required feature(s) with no offsite power available inoperable when its redundant required feature(s) is inoperable.

AND A.3 Restore offsite circuit to OPERABLE status.

24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from discovery of no offsite power to one train concurrent with inoperability of redundant required feature(s) 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> OR In accordance with the Risk Informed Completion Time Program B.

One DG inoperable.

B.1 Perform SR 3.8.1.1 for the offsite circuit(s).

AND B.2 Verify the required Station Blackout (SBO) DGs are available.

AND 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> AND Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> AND Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter (continued)

AC Sources - Operating 3.8.1 Wolf Creek - Unit 1 3.8-4 Amendment No. 123, 163, 234, TBD ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B.

(continued)

B.5.1 Restore DG to OPERABLE status.

OR B.5.2

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

Only applicable to planned maintenance once per cycle, per train, or unplanned corrective maintenance.

Restore DG to OPERABLE status.

72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> OR In accordance with the Risk Informed Completion Time Program 14 days OR In accordance with the Risk Informed Completion Time Program C.

Required Action B.2 and associated Completion Time not met.

C.1 Restore DG to OPERABLE status.

OR 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> from Condition B entry OR In accordance with the Risk Informed Completion Time Program (continued)

AC Sources - Operating 3.8.1 Wolf Creek - Unit 1 3.8-5 Amendment No. 123, 163, TBD ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME C.

(continued)

C.2 Restore DG to OPERABLE status.

OR C.3 Restore required SBO DGs to available status.

OR C.4 Restore required SBO DGs to available status.

NOTE--------

Only allowed once within any given extended DG Completion Time 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from Condition C entry OR In accordance with the Risk Informed Completion Time Program 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> from Condition B entry

NOTE--------

Only allowed once within any given extended DG Completion Time 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from Condition C entry (continued)

AC Sources - Operating 3.8.1 Wolf Creek - Unit 1 3.8-6 Amendment No. 123, 163, 234, TBD ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME D.

Two offsite circuits inoperable.

D.1

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

In MODES 1, 2, and 3, the turbine driven auxiliary feedwater pump is considered a required redundant feature.

Declare required feature(s) inoperable when its redundant required feature(s) is inoperable.

AND D.2 Restore one offsite circuit to OPERABLE status.

12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> from discovery of Condition D concurrent with inoperability of redundant required features 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> OR In accordance with the Risk Informed Completion Time Program E.

One offsite circuit inoperable.

AND One DG inoperable.

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

Enter applicable Conditions and Required Actions of LCO 3.8.9, "Distribution Systems - Operating,"

when Condition E is entered with no AC power source to any train.

E.1 Restore offsite circuit to OPERABLE status.

12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> OR In accordance with the Risk Informed Completion Time Program (continued)

AC Sources - Operating 3.8.1 Wolf Creek - Unit 1 3.8-7 Amendment No. 123, 163, 234, TBD ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME E.

(continued)

OR E.2 Restore DG to OPERABLE status.

12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> OR In accordance with the Risk Informed Completion Time Program F.

Two DGs inoperable.

F.1 Restore one DG to OPERABLE status.

2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> G.

One load shedder and emergency load sequencer inoperable.

G.1 Declare affected DG and offsite circuit inoperable.

AND G.2 Restore load shedder and emergency load sequencer to OPERABLE status.

Immediately 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> OR In accordance with the Risk Informed Completion Time Program (continued)

AC Sources - Operating 3.8.1 Wolf Creek - Unit 1 3.8-8 Amendment No. 123, 163, 234, TBD ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME H.

Required Action and associated Completion Time of Condition A, C, D, E, F, or G not met.

OR Required Actions B.1, B.3, B.4.1, B.4.2, B.5.1, and B.5.2 and associated Completion Time not met.

H.1 Be in MODE 3.

AND H.2 Be in MODE 5.

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

Three or more required AC sources inoperable.

I.1 Enter LCO 3.0.3 Immediately

Attachment IV to 001167 Page 1 of 13 Proposed Technical Specification Bases Changes with TS 3.8.1 for Audit Question EEEB-01 (For Information Only)

AC Sources - Operating B 3.8.1 Wolf Creek - Unit 1 B 3.8.1-6 Revision 93 BASES ACTIONS A.2 (continued)

OPERABILITY of the turbine driven auxiliary feedwater pump in this Condition, since the remaining OPERABLE motor driven auxiliary feedwater pump is not by itself capable of providing 100% of the auxiliary feedwater flow assumed in the safety analysis.

The Completion Time for Required Action A.2 is intended to allow the operator time to evaluate and repair any discovered inoperabilities. This Completion Time also allows for an exception to the normal "time zero" for beginning the allowed outage time "clock." In this Required Action, the Completion Time only begins on discovery that both:

a.

The train has no offsite power supplying its loads; and b.

A required feature on the other train is inoperable and not in the safeguards position.

If at any time during the existence of Condition A (one offsite circuit inoperable) a redundant required feature subsequently becomes inoperable, this Completion Time begins to be tracked.

Discovering no offsite power to one train of the onsite Class 1E Electrical Power Distribution System coincident with one or more inoperable required support or supported features, or both, that are associated with the other train that has offsite power, results in starting the Completion Times for the Required Action. Twenty-four hours is acceptable because it minimizes risk while allowing time for restoration before subjecting the unit to transients associated with shutdown.

The remaining OPERABLE offsite circuit and DGs are adequate to supply electrical power to Train A and Train B of the onsite Class 1E Distribution System. The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time takes into account the component OPERABILITY of the redundant counterpart to the inoperable required feature. Additionally, the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time takes into account the capacity and capability of the remaining AC sources, a reasonable time for repairs, and the low probability of a DBA occurring during this period.

A.3 According to Regulatory Guide 1.93 (Ref. 6), operation may continue in Condition A for a period that should not exceed 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. With one offsite circuit inoperable, the reliability of the offsite system is degraded, and the potential for a loss of offsite power is increased, with attendant potential for a challenge to the unit safety systems. In this Condition, Alternately, a Completion Time can be determined in accordance with the Risk Informed Completion Time Program.

AC Sources - Operating B 3.8.1 Wolf Creek - Unit 1 B 3.8.1-7 Revision 93 BASES ACTIONS A.3 (continued) however, the remaining OPERABLE offsite circuit and DGs are adequate to supply electrical power to the onsite Class 1E Distribution System.

The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Completion Time takes into account the capacity and capability of the remaining AC sources, a reasonable time for repairs, and the low probability of a DBA occurring during this period.

The second Completion Time for Required Action A.3 establishes a limit on the maximum time allowed for any combination of required AC power sources to be inoperable during any single contiguous occurrence of failing to meet the LCO. If Condition A is entered while, for instance, a DG is inoperable and that DG is subsequently returned OPERABLE, the LCO may already have been not met for up to 14 days. This could lead to a total of 17 days, since initial failure to meet the LCO, to restore the offsite circuit. At this time, a DG could again become inoperable and an additional 14 days allowed prior to complete restoration of the LCO. The 17 day Completion Time provides a limit on the time allowed in a specified condition after discovery of failure to meet the LCO. Although highly unlikely, this could continue indefinitely if not limited. This limit is considered reasonable for situations in which Conditions A and B are entered concurrently. This limits the time the plant can alternate between Conditions A, B, and E (see Completion Time Example 1.3-3). The AND connector between the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and 17 day Completion Times means that both Completion Times apply simultaneously, and the more restrictive Completion Time must be met.

Tracking the 17 day Completion Time is a requirement for beginning the Completion Time clock that is in addition to the normal Completion Time requirements. With respect to the 17 day Completion Time, the time zero is specified as beginning at the time LCO 3.8.1 was initially not met, instead of at the time Condition A was entered. This results in the requirement, when in this Condition, to track the time elapsed from both the Condition A time zero, and the time zero when LCO 3.8.1 was initially not met. Refer to Section 1.3, Completion Times, for a more detailed discussion of the purpose of the from discovery of failure to meet the LCO portion of the Completion Time.

AC Sources - Operating B 3.8.1 Wolf Creek - Unit 1 B 3.8.1-10 Revision 93 BASES ACTIONS B.4.1 and B.4.2 (continued)

Required Action B.4.1 provides an allowance to avoid unnecessary testing of OPERABLE DG. If it can be determined that the cause of the inoperable DG does not exist on the OPERABLE DG, SR 3.8.1.2 does not have to be performed. If the cause of inoperability exists on the other DG, it would be declared inoperable upon discovery and Condition F of LCO 3.8.1 would be entered. Once the failure is repaired, the common cause failure no longer exists, and Required Action B.4.1 is satisfied. If the cause of the initial inoperable DG cannot be confirmed not to exist on the remaining DG, performance of SR 3.8.1.2 suffices to provide assurance of continued OPERABILITY of that DG. Required Action B.4.2 is modified by a Note stating that it is satisfied by the automatic start and sequence loading of the DG. The Note indicates that an additional start of the DG for test purposes only, is not required if the DG has automatically started and loaded following a loss of the offsite power source to its respective bus (Ref. 16).

In the event the inoperable DG is restored to OPERABLE status prior to completing either B.4.1 or B.4.2, the plant corrective action program will continue to evaluate the common cause possibility. This continued evaluation, however, is no longer under the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> constraint imposed while in Condition B.

According to Generic Letter 84-15 (Ref. 7), 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is reasonable to confirm that the OPERABLE DG is not affected by the same problem as the inoperable DG.

B.5 In Condition B, the remaining OPERABLE DGs and offsite circuits are adequate to supply electrical power to the onsite Class 1E Distribution System. The 14 day Completion Time takes into account the capacity and capability of the remaining AC sources (including the required SBO DGs), a reasonable time for repairs, and the low probability of a DBA occurring during this period.

When one DG is inoperable due to either preplanned maintenance (preventive or corrective) or unplanned corrective maintenance work, the Completion Time can be extended from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 14 days if the required SBO DGs are verified available for backup operation in accordance with Required Action B.2. The 14 day Completion Time for an inoperable DG will be used no more than once in an 18-month period on a per DG basis to perform DG planned maintenance.

B.5.1 and B.5.2 See Insert B3.8.1-10b for inserted statements into highlighted text.

(Reference 18).

replace "once in an 18-month period" with "once per reactor operating cycle" an inoperable DG will be used no more than once in an 18-month period on a per DG basis to perform DG planned maintenance.

In Condition B, the remaining OPERABLE DGs and offsite circuits are In Condition B, the remaining OPERABLE DGs and offsite circuits are adequate to supply electrical power to the onsite Class 1E Distribution adequate to supply electrical power t System. The 14 day Completion Time takes into account the capacity System. The 14 day Completion Time takes into account the capacity and capability of the remaining AC sources (including the required SBO and capability of the remaining AC sources (including the required SBO DGs), a reasonable time for repairs, and the low probability of a DBA DGs), a reasonable time for repairs, and the low probability of a DBA occurring during this period.

When one DG is inoperable due to either preplanned maintenance When one DG is inoperable due to either preplanned maintenance (preventive or corrective) or unplanned corrective maintenance work, the (preventive or corrective) or unplanned corrective maintenance work, the Completion Time can be extended from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 14 days if the Completion Time can be extended from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 14 days if the required SBO DGs are verified available for backup operation in required SBO DGs are verified available for backup operation in accordance with Required Action B.2. The 14 day Completion Time for accordance with Required Action B.2. The 14 day Completion Time for an inoperable DG will be used no more than once in an 18-month period an inoperable DG will be used no more than once in an 18-month period

Insert B3.8.1-10b (For clarity, text from the entire B.5 section, revised to B.5.1 and B.5.2, is shown.)

B.5.1 and B.5.2 In Condition B, the remaining OPERABLE DGs and offsite circuits are adequate to supply electrical power to the onsite Class 1E Distribution System. Condition B.5.1, with a Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, is used for normal planned maintenance when not in a planned or unplanned 14-day Completion Time. The 14-day Completion Time, associated with Condition B.5.2, takes into account the capacity and capability of the remaining AC sources (including the required SBO DGs), a reasonable time for repairs, and the low probability of a DBA occurring during this period.

With either B.5.1 or B.5.2, if the required SBOs become unavailable, the appropriate Condition C is entered.

When one DG is inoperable due to either preplanned maintenance (preventive or corrective) or unplanned corrective maintenance work, the Completion Time can be extended from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 14 days if the required SBO DGs are verified available for backup operation in accordance with Required Action B.2. The 14-day Completion Time for an inoperable DG will be used no more than once in an 18-month periodonce per reactor operating cycle on a per DG basis to perform DG planned maintenance (Reference 18).

Alternatively, when either Condition B.5.1 or B.5.2 applies, a Completion Time may be determined in accordance with the Risk Informed Completion Time Program. If an emergent, unplanned condition is identified while in B.5.1, Condition B.5.2 may be entered without applying the Risk-Informed Completion Time Program, and the 14-day Completion Time continues from the time B.5.1 was first entered.

Regardless of how B.5.2 is entered, the Risk Informed Completion Time Program remains available for use.

Administrative controls are required whenever Condition B.5.2 is entered for a planned or unplanned DG outage that will extend beyond 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

Administrative controls applied ensure or require that:

a. Weather conditions are conducive to an extended DG Completion Time.
b. The offsite power supply and switchyard condition are conducive to an extended DG Completion Time, which includes ensuring that switchyard access is restricted and no elective maintenance within the switchyard is performed that would challenge offsite power availability. Elective maintenance or testing that would challenge offsite power availability is that activity that could result in an electrical power distribution system (offsite circuit or transmission network) transient or make the offsite circuit(s) unavailable or inoperable (Reference 17). The operational risk assessment procedure provides a list of equipment that could challenge offsite power availability.
c. No equipment or systems assumed to be available for supporting the extended DG Completion Time are removed from service. The equipment or systems assumed to be available (including required support systems, i.e., associated room coolers, etc.) are as follows:
  • Component Cooling Water System (both trains and all four pumps)

AC Sources - Operating B 3.8.1 Wolf Creek - Unit 1 B 3.8.1-11 Revision 93 BASES ACTIONS B.5 (continued)

The second Completion Time for Required Action B.5 establishes a limit on the maximum time allowed for any combination of required AC power sources to be inoperable during any single contiguous occurrence of failing to meet the LCO. If Condition B is entered while, for instance, an offsite circuit is inoperable and that circuit is subsequently restored OPERABLE, the LCO may already have been not met for up to 14 days.

This could lead to a total of 17 days, since initial failure to meet the LCO, to restore the DGs. At this time, an offsite circuit could again become inoperable, the DGs restored OPERABLE, and an additional 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> (for a total of 20 days) allowed prior to complete restoration of the LCO. The 17 day Completion Time provides a limit on time allowed in a specified condition after discovery of failure to meet the LCO. This limit is considered reasonable for situations in which Conditions A and B are entered concurrently. This limits the time the plant can alternate between Conditions A, B, and D (see Completion Time Example 1.3-3). The AND connector between the 14 day and 17 day Completion Times means that both Completion Times apply simultaneously, and the more restrictive Completion Time must be met.

Tracking the 17 day Completion Time is a requirement for beginning the Completion Time clock that is in addition to the normal Completion Time requirements. With respect to the 17 day Completion Time, the time zero is specified as beginning at the time LCO 3.8.1 was initially not met, instead of at the time Condition B was entered. This results in the requirement, when in this Condition, to track the time elapsed from both the Condition B time zero, and the time zero when LCO 3.8.1 was initially not met. Refer to Section 1.3, Completion Times, for a more detailed discussion of the purpose of the from discovery of failure to meet the LCO portion of the Completion Time.

Administrative controls are required whenever Condition B is entered for a planned or unplanned DG outage that will extend beyond 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

Administrative controls applied ensure or require that:

a.

Weather conditions are conducive to an extended DG Completion Time.

B.5.1 and B.5.2 B.5.2

AC Sources - Operating B 3.8.1 Wolf Creek - Unit 1 B 3.8.1-12 Revision 93 BASES ACTIONS B.5 (continued) b.

The offsite power supply and switchyard condition are conducive to an extended DG Completion Time, which includes ensuring that switchyard access is restricted and no elective maintenance within the switchyard is performed that would challenge offsite power availability. Elective maintenance or testing that would challenge offsite power availability is that activity that could result in an electrical power distribution system (offsite circuit or transmission network) transient or make the offsite circuit(s) unavailable or inoperable (Reference 17). The operational risk assessment procedure provides a list of equipment that could challenge offsite power availability.

c.

No equipment or systems assumed to be available for supporting the extended DG Completion Time are removed from service. The equipment or systems assumed to be available (including required support systems, i.e., associated room coolers, etc.) are as follows:

  • Component Cooling Water System (both trains and all four pumps)

C.1, C.2, C.3 and C.4 If the required SBO DGs are or becomes unavailable with an inoperable DG, then action is required to restore the DG to OPERABLE status or restore the required SBO DGs to available status. Required Action C.1 requires restoring the DG to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> from declaring the DG inoperable and Condition B entry. Required Action C.3 requires restoring the required SBO DG(s) to available status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> from declaring the DG inoperable and Condition B entry.

Required Action C.2 requires restoring the DG to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from Condition C entry. Required Action C.4 requires restoring the required SBO DGs to available status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from Condition C entry. The Completion Times for Required Actions C.2 and C.4 are modified by a Note indicating that the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from Condition C entry is only allowed once within any given extended DG Completion Time. Utilization of Required Actions C.2 and C.4 are typically applicable Alternately, a Completion Time can be determined in accordance with the Risk Informed Completion Time Program.

B.5.1 and B.5.2

AC Sources - Operating B 3.8.1 Wolf Creek - Unit 1 B 3.8.1-13 Revision 93 BASES ACTIONS C.1, C.2, C.3, and C.4 (continued) 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> after entry into Condition B (i.e., when the extended 14 day Completion Time is utilized). The total time to restore an inoperable DG cannot exceed 14 days (per the Completion Time of Required Action B.5).

The Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is consistent with Regulatory Guide 1.93 (Ref. 6). The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Completion Time takes into account the capacity and capability of the remaining AC sources, a reasonable time for repairs, and low probability of a DBA occurring during this period.

In addition to the markup below, including this page to show the complete sentence which starts on the previous page (B3.8.1-12) and continues here. The complete sentence clarifies a comment from Audit Question EEEB-01.

B.5.2).

AC Sources - Operating B 3.8.1 Wolf Creek - Unit 1 B 3.8.1-15 Revision 47 BASES ACTIONS D.1 and D.2 (continued)

If at any time during the existence of Condition D (two offsite circuits inoperable) a required feature becomes inoperable, this Completion Time begins to be tracked.

According to Regulatory Guide 1.93 (Ref. 6), operation may continue in Condition D for a period that should not exceed 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This level of degradation means that the offsite electrical power system does not have the capability to effect a safe shutdown and to mitigate the effects of an accident; however, the onsite AC sources have not been degraded. This level of degradation generally corresponds to a total loss of the immediately accessible offsite power sources.

Because of the normally high availability of the offsite sources, this level of degradation may appear to be more severe than other combinations of two AC sources inoperable that involve one or more DGs inoperable.

However, two factors tend to decrease the severity of this level of degradation:

a.

The configuration of the redundant AC electrical power system that remains available is not susceptible to a single bus or switching failure; and b.

The time required to detect and restore an unavailable offsite power source is generally much less than that required to detect and restore an unavailable onsite AC source.

With both of the required offsite circuits inoperable, sufficient onsite AC sources are available to maintain the unit in a safe shutdown condition in the event of a DBA or transient. In fact, a simultaneous loss of offsite AC sources, a LOCA, and a worst case single failure were postulated as a part of the design basis in the safety analysis. Thus, the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time provides a period of time to effect restoration of one of the offsite circuits commensurate with the importance of maintaining an AC electrical power system capable of meeting its design criteria.

According to Reference 6, with the available offsite AC sources, two less than required by the LCO, operation may continue for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. If two offsite sources are restored within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, unrestricted operation may continue. If only one offsite source is restored within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, power operation continues in accordance with Condition A.

Alternately, a Completion Time can be determined in accordance with the Risk Informed Completion Time Program.

AC Sources - Operating B 3.8.1 Wolf Creek - Unit 1 B 3.8.1-16 Revision 26 BASES ACTIONS E.1 and E.2 (continued)

Pursuant to LCO 3.0.6, the Distribution System ACTIONS would not be entered even if all AC sources to it were inoperable, resulting in de -

energization. Therefore, the Required Actions of Condition E are modified by a Note to indicate that when Condition E is entered with no AC source to any given train (i.e., to Train A or Train B), the Conditions and Required Actions for LCO 3.8.9, "Distribution Systems - Operating," must be immediately entered. This allows Condition D to provide requirements for the loss of one offsite circuit and one DG, without regard to whether a train is de-energized. LCO 3.8.9 provides the appropriate restrictions for a de-energized train.

According to Regulatory Guide 1.93 (Ref. 6), operation may continue in Condition E for a period that should not exceed 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

In Condition E, individual redundancy is lost in both the offsite electrical power system and the onsite AC electrical power system. Since power system redundancy is provided by two diverse sources of power, however, the reliability of the power systems in this Condition may appear higher than that in Condition C (loss of both required offsite circuits). This difference in reliability is offset by the susceptibility of this power system configuration to a single bus or switching failure. The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Completion Time takes into account the capacity and capability of the remaining AC sources, a reasonable time for repairs, and the low probability of a DBA occurring during this period.

F.1 With Train A and Train B DGs inoperable, there are no remaining standby AC sources. Thus, with an assumed loss of offsite electrical power, insufficient standby AC sources are available to power the minimum required ESF functions. Since the offsite electrical power system is the only source of AC power for this level of degradation, the risk associated with continued operation for a very short time could be less than that associated with an immediate controlled shutdown (the immediate shutdown could cause grid instability, which could result in a total loss of AC power). Since any inadvertent generator trip could also result in a total loss of offsite AC power, however, the time allowed for continued operation is severely restricted. The intent here is to avoid the risk associated with an immediate controlled shutdown and to minimize the risk associated with this level of degradation.

Alternately, a Completion Time can be determined in accordance with the Risk Informed Completion Time Program.

AC Sources - Operating B 3.8.1 Wolf Creek - Unit 1 B 3.8.1-17 Revision 93 BASES ACTIONS F.1 (continued)

According to Reference 6, with both DGs inoperable, operation may continue for a period that should not exceed 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.

G.1 and G.2 Required Action G.1 provides assurance that the appropriate Action is entered for the affected DG and offsite circuit if its associated LSELS becomes inoperable. An LSELS failure results in the inability of the EDG to start upon a loss of ESF bus voltage or degraded voltage condition.

Additionally, LSELS trips the ESF bus normal and alternate feeder supplies and trips non-essential loads. A sequencer failure results in the inability to start all or part of the safety loads powered from the associated ESF bus and thus when an LSELS is inoperable it is appropriate to immediately enter the Conditions for an inoperable DG and offsite circuit.

Because an inoperable LSELS affects all or part of the safety loads, an immediate Completion Time is appropriate.

The LSELS is an essential support system to both the offsite circuit and the DG associated with a given ESF bus. Furthermore, the sequencer is on the primary success path for most major AC electrically powered safety systems powered from the associated ESF bus. Therefore, loss of an ESF bus sequencer affects every major ESF system in the division.

The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Completion Time of Required Action G.2 provides a period of time to correct the problem commensurate with the importance of maintaining sequencer OPERABILITY. This time period also ensures that the probability of an accident (requiring sequencer OPERABILITY) occurring during periods when the sequencer is inoperable is minimal.

H.1 and H.2 If the inoperable AC electric power sources or the load shedder and emergency load sequencer cannot be restored to OPERABLE status within the required Completion Time, or Required Actions B.1, B.3, B.4.1, B.4.2, and B.5 cannot be met within the required Completion Times, 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 <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and to MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required unit conditions from full power conditions in an orderly manner and without challenging plant systems.

Alternately, a Completion Time can be determined in accordance with the Risk Informed Completion Time Program.

B.5.1, and B.5.2

AC Sources - Operating B 3.8.1 Wolf Creek - Unit 1 B 3.8.1-34 Revision 93 BASES REFERENCES

11.

ANSI C84.1-1982 (continued)

12. IEEE Standard 308-1978.
13.

Configuration Change Package (CCP) 08052, Revision 1, April 23, 1999.

14.

Amendment No. 161, April 21, 2005.

15.

Amendment No. 154, August 4, 2004.

16.

Amendment No. 8, May 29, 1987.

17.

Condition Report 15727.

18. Amendment No. 234, November 4, 2022.

Enclosure I to 001167 Page 1 of 6 Revisions to Select Pages from License Amendment Request 000670 Revised pages included as noted by specific audit responses:

1. Enclosure I to 000670, pages 18, 19, 20, 21, with Table E1-1 Revisions for Audit Questions EEEB-02 and EEEB-03
2. Attachment I to 000670, page 4, with Administrative Variation No. 6 Revision for Audit Question STSB-03 to ET 000670 Page 18 of 33 Table E1-1: In Scope TS/LCO Conditions to Corresponding PRA Functions TS Condition TS Condition Description SSCs Covered by TS LCO Condition SSCs Modeled in PRA Function Required by TS LCO Condition Design Success Criteria PRA Success Criteria Other Comments 3.8.1.A AC Sources -

Operating -

One offsite circuit inoperable Two qualified circuits between the offsite transmission network and the onsite Class 1E AC Electrical Power Distribution System Yes Provide power from offsite transmission network to onsite Class 1E buses One qualified circuit between the offsite transmission network and the onsite Class 1E AC Electrical Power Distribution System Same as design criteria.

As needed to supply AC power to supported functions.

None 3.8.1.B AC Sources -

Operating -

One DG inoperable Two Diesel Generators (DGs) capable of supplying the onsite Class 1E power distribution subsystem(s)

Yes Provide power to safety-related buses when offsite power to the bus is lost One DG capable of supplying the onsite Class 1E AC Electrical Power Distribution System The 4160V Class 1E buses are modeled to automatically isolate from offsite power and align to the applicable onsite power (DGs) upon a loss of offsite power.

Emergency Power (DGs),

Station Blackout (SBO) DG System, Normal or Alternate Offsite power paths, and Crosstie Power are all credited in the PRA model.

None Enclosure to 001167, Page 2 of 6 to ET 000670 Page 19 of 33 Table E1-1: In Scope TS/LCO Conditions to Corresponding PRA Functions TS Condition TS Condition Description SSCs Covered by TS LCO Condition SSCs Modeled in PRA Function Required by TS LCO Condition Design Success Criteria PRA Success Criteria Other Comments 3.8.1.C AC Sources -

Operating -

Required Action B.2 and associated Completion Time not met Two DGs capable of supplying the onsite Class 1E power distribution subsystem(s)

Yes Provide power to safety-related buses when offsite power to the bus is lost One DG capable of supplying the onsite Class 1E AC Electrical Power Distribution System The 4160V Class 1E buses are modeled to automatically isolate from offsite power and align to the applicable onsite power (DGs) upon a loss of offsite power.

Emergency Power (DGs),

SBO DG System, Normal or Alternate Offsite power paths, and Crosstie Power are all credited in model.

None 3.8.1.D AC Sources -

Operating -

Two offsite circuits inoperable Two qualified circuits between the offsite transmission network and the onsite Class 1E AC Electrical Power Distribution System Yes Provide power from offsite transmission network to onsite Class 1E buses One qualified circuit between the onsite AC power sources the offsite transmission network offsite transmission network and the onsite 1E AC Electrical Power Distribution System The 4160V Class 1E Buses are modeled to automatically isolate from offsite power and align to the applicable onsite power (DGs) upon a loss of offsite power.

With both offsite circuits inoperable, sufficient onsite AC sources are available to maintain the unit in a safe shutdown condition in the event of a design basis accident or transient.

Enclosure to 001167, Page 3 of 6 to ET 000670 Page 20 of 33 Table E1-1: In Scope TS/LCO Conditions to Corresponding PRA Functions TS Condition TS Condition Description SSCs Covered by TS LCO Condition SSCs Modeled in PRA Function Required by TS LCO Condition Design Success Criteria PRA Success Criteria Other Comments Emergency Power (DGs),

SBO DG System, Normal or Alternate Offsite power paths, and Crosstie Power are all credited in model.

3.8.1.E AC Sources -

Operating -

One offsite circuit inoperable AND One DG inoperable Two qualified circuits between the offsite transmission network and the onsite Class 1E AC Electrical Power Distribution System; and two DGs capable of supplying the onsite Class 1E power distribution subsystem(s)

Yes Reference back to LCOs 3.8.1.A and 3.8.1.B Reference back to LCOs 3.8.1.A and 3.8.1.B The 4160V Class 1E buses are modeled to automatically isolate from offsite power and align to the applicable onsite power (DGs) upon a loss of offsite power.

Emergency Power (DGs),

SBO DG System, Normal or Alternate Offsite power paths, and Crosstie Power are all credited in model.

None Enclosure to 001167, Page 4 of 6 No Changes Showing continuation of 3.8.1.D.

to ET 000670 Page 21 of 33 Table E1-1: In Scope TS/LCO Conditions to Corresponding PRA Functions TS Condition TS Condition Description SSCs Covered by TS LCO Condition SSCs Modeled in PRA Function Required by TS LCO Condition Design Success Criteria PRA Success Criteria Other Comments 3.8.1.G AC Sources -

Operating -

One load shedder and emergency load sequencer inoperable Load Shedder and Emergency Load Sequencer (LSELS) for Train A and Train B

Yes Required functions of LSELSs are initiating a DG start upon a detected undervoltage condition, tripping of the incoming offsite power upon a detected undervoltage or degraded voltage condition, shedding of nonessential loads, and proper sequencing of loads One LSELS: One Train A of LSELS or one Train B LSELS Same as design criteria None 3.8.4.A DC Sources -

Operating -

One DC electrical power subsystems inoperable The Train A and Train B DC electrical power subsystems Yes Ensure availability of required DC power to shut down the reactor and maintain it in a safe condition One DC electrical power subsystem available Same as design criteria.

As needed to supply DC power to supported functions.

None 3.8.7.A Inverters -

Operating -

One required inverter inoperable Train A and Train B inverters Yes Provide reliable AC power to vital instrument power boards One train (Train A or Train B) of inverters providing the associated vital As needed to supply supported functions.

Success of None Enclosure to 001167, Page 5 of 6

2.3.1 Administrative Variations The following variations taken from the TSTF-505-A template for NUREG-1431 are considered to be administrative in nature.

1.

WCGS RAs/Conditions with alpha-numeric designations that differ from the corresponding Westinghouse Standard Technical Specifications (NUREG-1431) RAs (as applicable), have wording that is slightly different, and have differing existing Completion Times with a similar intent are administrative variations from TSTF-505-A with no effect on the NRC staff's final revised model safety evaluation.

2.

For NUREG-1431 RAs that are not contained in the WCGS TS, the corresponding NUREG-1431 mark-ups included in TSTF-505-A for these RAs and Completion Times are not applicable to WCGS. These are administrative variations from TSTF-505-A with no effect on the NRC staff's final revised model safety evaluation.

3.

Various TSTF-505-A Section 3.3 instrumentation Conditions are invoked by instrumentation Functions contained in tables. The analogous WCGS instrumentation Functions may have different Conditions referenced, or have slightly different wording.

This includes differences in re-lettering in the tables. These are administrative variations from TSTF-505-A that meet the criteria for administering a RICT, and have no effect on the NRC staff's final revised model safety evaluation.

4.

TSTF-505-A applies RICT to certain RAs that require additional plant-specific justification. For several of these RAs, the WCGS design has not been able to meet the necessary justification, so a RICT has not been applied. For example, as the proposed WCGS RICT Program is applicable in Modes 1 and 2, WCNOC will not adopt changes in TSTF-505-A for RAs that are only applicable in Mode 3 and below.

5.

TSTF-505-A applies RICT to TS 3.6.3 RA A.1. The WCGS TS differ in that Condition A references the exception for purge valve leakage (Condition D), and the Completion Times that ultimately informed TSTF-446-A, Risk Informed Evaluation of Extensions to Containment Isolation Valve Completion Times (WCAP-15791).1 This Condition A wording that includes the later language of TSTF-446-A does not invalidate the ability to alternatively apply a RICT. The RICT for this RA is included in NUREG-1431, Revision 5.

6.

Certain WCGS TS did not include a RICT because it could not be verified that there would not be a loss of function, or that the function was not adequately modeled in the PRA.

7.

In TSTF-505-A, new Required Action M.1 (Reduce THERMAL POWER to < P-7) is later duplicated in new RA Q.1. This appears to be an error in the traveler. WCNOC has 1 WCGS was the lead plant for the Westinghouse Owners Group change based on WCAP-15791 with approval of Amendment 167 on September 28, 2006, and ultimately resulted in NRC approval of the WCAP on February 13, 2008, and TSTF-446 on July 3, 2010.

Attachment I to 000670 Page 4 of 15 disposition of No variation is provided. Where a variation is taken, the disposition provides a cross-reference to the paragraph in this Attachment that provides justification.

Not used.

Enclosure to 001167, Page 6 of 6

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