ML22021B598
| ML22021B598 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 02/23/2022 |
| From: | Samson Lee Plant Licensing Branch IV |
| To: | Reasoner C Wolf Creek |
| Lee S, 301-415-3168 | |
| References | |
| EPID L 2021 LLA 0172 | |
| Download: ML22021B598 (15) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON , D.C. 20555-0001 February 23, 2022 Mr. Cleveland Reasoner Chief Executive Officer and Chief Nuclear Officer Wolf Creek Nuclear Operating Corporation P.O. Box 411 Burlington, KS 66839
SUBJECT:
WOLF CREEK GENERATING STATION, UNIT 1 - ISSUANCE OF AMENDMENT NO. 231 RE: REVISION OF TECHNICAL SPECIFICATION 3.3.2, ENGINEERED SAFETY FEATURE ACTUATION SYSTEM (ESFAS) INSTRUMENTATION (EPID L-2021-LLA-0172)
Dear Mr. Reasoner:
The U.S. Nuclear Regulatory Commission (the Commission) has issued the enclosed Amendment No. 231 to Renewed Facility Operating License No. NPF-42 for the Wolf Creek Generating Station, Unit 1. The amendment consists of proposed changes to the Technical Specifications (TSs) in response to your application dated September 29, 2021, as supplemented by letter dated December 22, 2021.
The amendment revises TS 3.3.2, Engineered Safety Feature Actuation System (ESFAS)
Instrumentation, by adding a new Required Action N.1 to require restoration of an inoperable balance of plant ESFAS train to operable status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
A copy of the related Safety Evaluation is enclosed. Notice of Issuance will be included in the Commissions monthly Federal Register notice.
Sincerely,
/RA/
Samson S. Lee, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-482
Enclosures:
- 1. Amendment No. 231 to NPF-42
- 2. Safety Evaluation cc: Listserv
WOLF CREEK NUCLEAR OPERATING CORPORATION WOLF CREEK GENERATING STATION, UNIT 1 DOCKET NO. 50-482 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 231 License No. NPF-42
- 1. The Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment to the Wolf Creek Generating Station, Unit 1 (the facility) Renewed Facility Operating License No. NPF-42 filed by the Wolf Creek Nuclear Operating Corporation (the Corporation), dated September 29, 2021, as supplemented by letter dated December 22, 2021, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commissions rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, as amended, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations and all applicable requirements have been satisfied.
Enclosure 1
- 2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment and paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-42 is hereby amended to read as follows:
(2) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through Amendment No. 231, and the Environmental Protection Plan contained in Appendix B, as revised through Amendment No 229, both of which are attached hereto, are hereby incorporated in the license. The Corporation shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3. The license amendment is effective as of its date of issuance and shall be implemented within 15 days of the date of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION Jennifer L. Digitally signed by Jennifer L. Dixon-Herrity Dixon-Herrity Date: 2022.02.23 07:27:40 -05'00' Jennifer L. Dixon-Herrity, Chief Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Renewed Facility Operating License and Technical Specifications Date of Issuance: February 23, 2022
ATTACHMENT TO LICENSE AMENDMENT NO. 231 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-42 WOLF CREEK GENERATING STATION, UNIT 1 DOCKET NO. 50-482 Replace the following pages of Renewed Facility Operating License No. NPF-42 and the Appendix A, Technical Specifications, with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.
Renewed Facility Operating License REMOVE INSERT 4 4 Technical Specifications REMOVE INSERT 3.3-28 3.3-28
4 (5) The Operating Corporation, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use in amounts as required any byproduct, source or special nuclear material without restriction to chemical or physical form, for sample analysis or instrument calibration or associated with radioactive apparatus or components; and (6) The Operating Corporation, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility.
C. This renewed operating license shall be deemed to contain and is subject to the conditions specified in the Commissions regulations in 10 CFR Chapter I and is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission, now or hereafter in effect; and is subject to the additional conditions specified or incorporated below:
(1) Maximum Power Level The Operating Corporation is authorized to operate the facility at reactor core power levels not in excess of 3565 megawatts thermal (100%
power) in accordance with the conditions specified herein.
(2) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through Amendment No. 231, and the Environmental Protection Plan contained in Appendix B, as revised through Amendment No. 229, both of which are attached hereto, are hereby incorporated in the license. The Corporation shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
(3) Antitrust Conditions Evergy Kansas South, Inc. and Evergy Metro, Inc. shall comply with the antitrust conditions delineated in Appendix C to this license.
(4) Environmental Qualification (Section 3.11, SSER #4, Section 3.11, SSER #5)*
Deleted per Amendment No. 141.
- The parenthetical notation following the title of many license conditions denotes the section of the supporting Safety Evaluation Report and/or its supplements wherein the license condition is discussed.
Renewed License No. NPF-42 Amendment No. 231
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 231 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-42 WOLF CREEK NUCLEAR OPERATING CORPORATION WOLF CREEK GENERATING STATION, UNIT 1 DOCKET NO. 50-482
1.0 INTRODUCTION
By application dated September 29, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21272A283), as supplemented by letter dated December 22, 2021 (ADAMS Accession No. ML21356A052), Wolf Creek Nuclear Operating Corporation (the licensee) requested changes to the Technical Specifications (TSs) for Wolf Creek Generating Station, Unit 1 (Wolf Creek or WCGS).
The proposed changes would modify TS 3.3.2, Engineered Safety Feature Actuation System (ESFAS) Instrumentation, by adding a new Required Action N.1 to require restoration of an inoperable balance of plant ESFAS (BOP ESFAS or BOP-ESFAS) train to operable status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The proposed TS changes would provide allowable time and avoid a potential unplanned plant shutdown should a condition occur requiring BOP ESFAS corrective maintenance.
The supplemental letter dated December 22, 2021, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the U.S. Nuclear Regulatory Commission (NRC or the Commission) staffs original proposed no significant hazards consideration determination as published in the Federal Register on November 2, 2021 (86 FR 60486).
2.0 REGULATORY EVALUATION
2.1 System Description Section 7.3, Engineered Safety Feature Systems, of the Wolf Creek Updated Safety Analysis Report (USAR) (ADAMS Accession No. ML21168A116) states, in part:
The engineered safety feature actuation system (ESFAS) is comprised of the instrumentation and controls to sense accident situations and initiate the operation of necessary engineered safety features. The occurrence of a limiting fault, such as a loss-of-coolant accident (LOCA) or a steam line break, requires a Enclosure 2
reactor trip plus actuation of one or more of the engineered safety features in order to prevent or mitigate damage to the core and reactor coolant system components and ensure containment integrity.
In order to accomplish these design objectives, the engineered safety feature systems (ESFS) have proper and timely initiating signals which are supplied by the sensors, transmitters, and logic components making up the various instrumentation channels of the ESFAS.
A power interruption to the ESFS, in conjunction with a LOCA or other postulated accident, is believed to be a highly improbable event. However, the accident analyses for WCGS assume a loss of offsite power coincident with certain postulated events, such as a LOCA. In addition, it is assumed that a single failure occurs which causes the loss of one of the two onsite emergency diesel generators.
The licensee stated in Section 3.1, System Description, of Attachment I to the license amendment request (LAR) dated September 29, 2021:
The BOP ESFAS actuation logic processes signals from several sources, such as the Solid State Protection System (SSPS) logic outputs associated with safety injection, containment isolation - phase A, and low-low steam generator (SG) water level, the load shedder and emergency load sequencer (LSELS) logic outputs associated with ESF [engineered safety feature] bus undervoltage, inputs from various plant radiation monitors, inputs from main feedwater pump lube oil pressure switches (used for motor-driven auxiliary feedwater (AFW) pump actuation), and inputs from pressure switches in the AFW suction supply from the condensate storage tank (CST) in order to actuate ESF equipment. There are two redundant trains of BOP ESFAS actuation logic (separation groups 1 and 4, cabinets SA036D and SA036E, respectively), and a third actuation logic cabinet (separation group 2, cabinet SA036C) to actuate the turbine-driven AFW pump and reposition automatic valves required for that pumps operation (i.e., open turbine steam supply valves and the turbine trip and throttle valve). The separation group 2 BOP ESFAS actuation logic cabinet SA036C receives isolated inputs from both the SA036D and SA036E cabinets (separation groups 1 and 4) to start the turbine-driven AFW pump upon ESF bus undervoltage or upon low-low SG level in two or more steam generators.
2.2 Licensee Proposed Changes Current TS requirements:
The licensee stated in Section 2.1, Current Technical Specification Requirements, of Attachment I to the LAR:
TS 3.3.2 Condition N applies to TS Table 3.3.2-1, Engineered Safety Feature Actuation System Instrumentation, Function 6.c., Automatic Actuation Logic and Actuation Relays (BOP-ESFAS). With one BOP-ESFAS train inoperable, Required Action N.1 requires placing the plant in MODE 3 in 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and Required Action N.2 requires placing the plant in MODE 4 in 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
Licensee Proposed Changes:
The licensee stated, in part, in Section 2.3, Description of the Proposed Change, of Attachment I to the LAR:
The proposed change to TS 3.3.2 Condition N would add a new Required Action N.1 that requires the restoration of an inoperable BOP ESFAS train (TS Table 3.3.2-1 Function 6.c., Auxiliary Feedwater - Automatic Actuation Logic and Actuation Relays (BOP ESFAS)) to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
Existing Required Actions N.1 and N.2 would be changed to Required Actions N.2.1 and N.2.2, respectively, with the joining logic connector (AND) nested as required by TS 1.2, Logical Connectors. Required Actions N.2.1 and N.2.2 would be joined to new Required Action N.1 with an OR logic connector. The Completion Times for Required Actions N.2.1 and N.2.2 would be 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> and 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />, respectively, which reflect the typical shutdown track times (6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to MODE 3 and 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to MODE 4 as discussed in LCO
[Limiting Condition for Operation] 3.0.3) for reaching MODES 3 and 4 when a restoration action has not been met.
2.3 Reason for Proposed Changes The licensee stated, in part, in Section 2.2, Reason for the Proposed Change, of Attachment I to the LAR:
The proposed TS changes are being requested to provide flexibility to resolve emergent BOP ESFAS actuation logic and actuation relay deficiencies and avoid a potential unplanned plant shutdown and associated thermal transient, along with the potential challenges to safety systems during an unplanned shutdown, should a condition occur requiring BOP-ESFAS corrective maintenance.
On September 1, 2021, Control Room operators received numerous alarms indicating that a loss of power to SA036E (B train BOP ESFAS cabinet) had occurred. Instrument and Control technicians had test equipment connected inside the cabinet to support surveillance testing of radiation monitoring equipment in accordance with procedure STS IC-455B, Channel Calibration Control Room Air Intake Radiation Monitor GK RE-004. The Instrument and Control technicians reported the power failure on SA036E and removed the test equipment that was connected in the cabinet. Approximately, seven minutes after the receipt of the alarms, power was available to SA036E without any other actions taken. An inoperable BOP ESFAS train would result in the initiation of a plant shutdown in accordance with TS 3.3.2, Condition N.
The licensee stated, in part, in Section 2.4, Bases for Proposed Change, of Attachment I to the LAR:
The purpose of the proposed change is to provide an allowed outage time Required Action with a Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> for restoration of an inoperable BOP-ESFAS train. The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time is necessary to reduce the likelihood and unnecessary burden of a plant shutdown should an unplanned BOP ESFAS outage occur with the plant at power by providing
additional time to troubleshoot, repair (replacement of power supplies) and reestablish OPERABILITY of the inoperable BOP ESFAS train.
2.4 Regulatory Requirements The Commission's regulatory requirements related to the content of the TSs are set forth in Title 10 of the Code of Federal Regulations (10 CFR), Section 50.36, Technical specifications. The regulation under 10 CFR 50.36(c)(2) requires that TSs contain LCOs, which are the lowest functional capability or performance levels of equipment required for safe operation of the facility. When an LCO of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the TSs until the LCO can be met. Typically, the TSs require restoration of equipment in a timeframe commensurate with its safety significance, along with other engineering considerations. The regulation under 10 CFR 50.36(b) requires that TSs be derived from the analyses and evaluation included in the safety analysis report, and amendments thereto.
2.5 Regulatory Guidance Guidance for staff review of TSs is contained in NUREG-0800, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR [Light-Water Reactor]
Edition, Section 16.0, Technical Specifications, Revision 3, dated March 2010 (ADAMS Accession No. ML100351425). The NRC staff has prepared standard technical specifications (STSs) for each of the LWR nuclear steam supply systems and associated balance of plant equipment systems. The guidance specifies that the NRC staff review whether content and format of proposed TSs are consistent with the applicable STSs. Where TS provisions depart from the reference TSs, the NRC staff determines whether proposed differences are justified by uniqueness in plant design or other considerations. The applicable current STSs for Wolf Creek are contained in NUREG-1431, Standard Technical Specifications - Westinghouse Plants, Revision 4.0, Volume 1, Specifications, dated April 2012 (ADAMS Accession No. ML12100A222).
3.0 TECHNICAL EVALUATION
3.1 Deterministic Evaluation In the LAR, the licensee proposed a change to Condition N associated with BOP ESFAS -
Automatic Actuation Logic and Actuation Relays, Function 6.c. of TS Table 3.3.2-1. Currently, Condition N of TS 3.3.2 requires the plant to enter a shutdown track with no allowed outage time provided for restoration. The licensee proposed to revise Condition N to increase the shutdown track completion time (CT) in MODES 3 and 4 to provide restoration time.
The licensee stated, in part, in Section 2.4 of Attachment I to the LAR:
The proposed Required Action and associated Completion Time is consistent with Condition G (applicable to TS 3.3.2, Function 6.b., Automatic Actuation Logic and Actuation Relays (Balance of Plant ESFAS)) in NUREG-1431, Rev. 4, Standard Technical Specification Westinghouse Plants.
The NRC staff review found that the licensees proposed changes are consistent with NUREG-1431.
As stated in Wolf Creek USAR Section 7.3.6.1.1, System Description, the motor-driven AFW pumps are started on the occurrence of any one of the following signals:
- 1. Manual start
- 2. Safeguards sequence signal (initiated by safety injection signal or loss-of-offsite-power)
- 3. Auxiliary feedwater actuation (AFAS-M)
The regulation in 10 CFR 50.36(c)(2)(i) requires a licensee to shut down the reactor when an LCO is not met or follow specified remedial actions permitted by the TSs until the LCO can be met. Currently, Condition N allows no time for restoring the inoperable train to operable status and requires the licensee to be in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. The licensee is proposing to change the allowed CT for one inoperable train to allow 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore the train to operable status prior to having to shut down the reactor. During the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> CT, when one train is inoperable the other train is available to perform its safety function. In Section 3.4, Deterministic Assessment of Proposed New Required Action, of Attachment I to the LAR, the licensee stated, in part:
The OPERABLE BOP ESFAS train will continue to be capable of performing the necessary safety functions consistent with accident analysis assumptions.
The licensee also stated, in part, in Section 3.4 of Attachment I to the LAR:
The design and operation of the BOP-ESFAS is not altered by the proposed 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time for an inoperable BOP-ESFAS train. The safety analyses safety criteria stated in the Updated Safety Analysis Report (USAR) is not impacted by the proposed changes. Redundancy and diversity of the BOP-ESFAS trains are not altered because the system design and operation are not changed by the proposed change. The proposed change to the TSs will not allow plant operation in a configuration outside the plants design basis. The requirements credited in the accident analyses regarding the BOP-ESFAS remain the same.
If the second train also becomes inoperable during the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, safeguards sequence signal or manual operation will be available for starting the motor-driven AFW pumps. The licensee also provided a risk assessment in the LAR for extending the allowed CT from 0 to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The NRC staff considered the licensees risk insights as described in Section 3.2 of this safety evaluation and found the risk insights support the proposed change.
The NRC staff concludes that the licensees proposed revision to TS 3.3.2, Condition N, provides an acceptable remedial action when the LCO is not met. Additionally, the NRC staff compared the proposed revision to NUREG-1431, Revision 4, and finds that they are consistent. Therefore, the licensee will continue to meet the requirements of 10 CFR 50.36(c)(2)(i).
3.2 Risk Insights In Section 1.0, Summary Description, of Attachment I to the LAR, the licensee stated that the LAR was justified based on deterministic bases supplemented by risk insights. In Section 3.5, Risk Assessment, of Attachment I to the LAR, the licensee stated that a quantitative and
qualitative risk assessment was performed to support the LAR and provided the detailed risk assessment in Attachment II to the LAR.
Because this LAR is not a risk-informed application, the NRC staff did not review the licensees probabilistic risk assessment models to determine its technical acceptability as a basis to support this application. As a result, the NRC staff did not rely on the quantitative risk information provided by the licensee in Attachment II to the LAR. However, the NRC staff considered the licensees risk insights to aid in the deterministic review of the proposed change.
The NRC staff determined that special circumstances, as discussed in NUREG-0800, Section 19.2, Review of Risk Information Used to Support Permanent Plant-Specific Changes to the Licensing Basis: General Guidance, dated June 2007 (ADAMS Accession No. ML071700658), which would have necessitated additional risk information to be provided, did not exist for the proposed change.
In Section 5.11, Risk Insights, of Attachment II to the LAR, the licensee described the risk insights as a higher reliance on manual actions, an increase in the common cause failures of the actuation signals, and an increase in the anticipated transients without scram mitigation system actuation circuitry failure. The licensee noted that for internal floods, the dominant accident sequences for the condition of one ESFAS train unavailable involve the loss of room cooling for the unaffected (i.e., redundant) motor-driven AFW pump, which is generally caused by flood-induced failure of essential service water or component cooling water. The licensee also noted that the turbine-driven AFW pump function is still available.
In Section 4.1, External Hazards, of Attachment II to the LAR, the licensee described the fire hazard and noted that there are multiple options to maintain secondary side heat removal in the event that a fire fails the unaffected motor-driven AFW train concurrent with an unavailable auxiliary feedwater actuation signal (AFAS) train. For the seismic hazard, the licensee stated that a loss of offsite power is the primary impact expected. The licensee stated that the seismic-induced failure of the ESFAS logic cabinets is correlated and noted that the unavailability of one train does not impact the risk from a seismic event. For the high winds hazard, the licensee explained that the ESFAS logic cabinets were housed in Category I structures and mounted perpendicular to the exterior wall, which reduces the impact of concrete spalling. Further, the location of the ESFAS logic cabinets relative to each other is such that their failure due to spalling would be correlated and the unavailability of one train would not impact the risk from a high winds event.
In the supplemental letter dated December 22, 2021, the licensee provided clarification on the risk insights. The licensee described there are three signals from the BOP ESFAS actuation logic cabinets SA036D and SA036E that were considered in the development of risk insights.
These signals are the motor-driven AFAS, SG blowdown and sample isolation signal, and containment purge isolation signal. The licensee explained that an operator action was required for successful isolation of the SG blowdown and sample valves rather than the BOP ESFAS signal and the containment purge valves are normally closed, making the corresponding BOP ESFAS signal confirmatory in nature.
In the supplemental letter dated December 22, 2021, the licensee noted that there are no high-risk configurations arising solely from a loss of one train of BOP ESFAS. The licensee noted that automatic actuation of the unaffected train and manual actuation of the affected train remain available. The licensee further clarified that Procedure AP 22C-003, On-Line Nuclear Safety and Generation Risk Assessment, is used in conjunction with Procedures AP 22C-007,
Risk Management and Contingency Planning, and AP 22C-008, Qualitative Risk Management. The licensee stated that Procedure AP 22C-003 provides direction for documenting any change in risk due to emergent work activities. The licensee described that Procedure AP 22C-008 is used to determine the level of risk and develop risk mitigating actions for a specific activity. The licensee stated that these procedural requirements provide the necessary tools for identifying any required compensatory measures that may be required for an emergent condition requiring the entry into the proposed TS 3.3.2, Condition N, Required Action N.1.
In addition to reviewing the licensees risk insights, the NRC staff performed an independent assessment using the NRCs Standardized Plant Analysis Risk (SPAR) model for Wolf Creek.
The NRC staff used the SPAR model for Wolf Creek to assess the proposed change, including identifying risk insights and the dominant risk contributors for the proposed change. The NRC staff concluded the licensees risk insights support the proposed change and the licensee appropriately identified the dominant risk scenarios for the proposed change. The NRC staff did not identify the need for any unique compensatory measures for the proposed change.
The NRC staffs review also noted that the risk due to external hazards such as high winds and tornadoes, seismic events, and external flooding does not significantly change the risk from the proposed changes because loss of offsite power is the dominant impact of the external hazards and any additional impacts from an external hazard are not altered by the proposed change.
The NRC staffs review of the licensees risk insights finds that: (1) the licensee appropriately identified the dominant risk scenarios for the proposed change, and (2) the licensees available procedures appropriately manage the risk from the dominant risk scenarios. Therefore, the NRC staff concludes that the licensees risk insights support the proposed change.
3.3 Technical Evaluation Conclusion The NRC staff concludes that the licensees proposed revision to TS 3.3.2, Condition N, provides an acceptable remedial action when the LCO is not met. Additionally, the NRC staff compared the proposed revision to NUREG-1431, Revision 4, and found they are consistent.
Therefore, the licensee will continue to meet the requirements of 10 CFR 50.36(c)(2)(i). The NRC staff also concludes that the licensees risk insights support the proposed change.
Therefore, the NRC staff finds the licensees proposed revision to TS 3.3.2, Condition N, acceptable.
4.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Kansas State official was notified of the proposed issuance of the amendment on November 15, 2021. The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no
significant hazards consideration, published in the Federal Register on November 2, 2021 (86 FR 60486), and there has been no public comment on such finding. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
6.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) there is reasonable assurance that such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributors: H. Wagage, NRR S. Alferink, NRR S. Vasavada, NRR T. Sweat, NRR R. Stattel, NRR C. Cheung, NRR Date: February 23, 2022
ML22021B598 OFFICE NRR/DORL/LPL4/PM NRR/DORL/LPL4/LA NRR/DSS/STSB/BC NRR/DSS/SCPB/BC(A)
NAME SLee PBlechman VCusumano SJones DATE 1/21/2022 1/24/2022 1/21/2022 1/21/2022 OFFICE NRR/DEX/EICB/BC NRR/DRA/APLC/BC OGC NRR/DORL/LPL4/BC NAME MWaters SRosenberg JAzeizat JDixon Herrity DATE 1/21/2022 1/12/2022 2/4/2022 2/23/2022 OFFICE NRR/DORL/LPL4/PM NAME SLee DATE 2/23/2022