Text

Issuance of Amendment No. Regarding the Revision of Technical Specifications to Adopt TSTF-566 and TSTF-580
	ML25086A138
Person / Time
Site:	Monticello
Issue date:	04/22/2025
From:	Wetzel B; NRC/NRR/DORL/LPL3
To:	Hafen S; Northern States Power Company, Minnesota
References
	EPID L-2024-LLA-0154
	Download: ML25086A138 (1)
	v • d • e

April 22, 2025 Shawn Hafen Site Vice President Northern States Power Company Minnesota Monticello Nuclear Generating Plant 2807 West County Road 75 Monticello, MN 55362

SUBJECT:

MONTICELLO NUCLEAR GENERATING PLANT - ISSUANCE OF AMENDMENT NO. 216 REGARDING THE REVISION OF TECHNICAL SPECIFICATIONS TO ADOPT TSTF-566, REVISE ACTIONS FOR INOPERABLE RHR SHUTDOWN COOLING SUBSYSTEMS, AND TSTF-580, PROVIDE EXCEPTION FROM ENTERING MODE 4 WITH NO OPERABLE RHR SHUTDOWN COOLING (EPID L-2024-LLA-0154)

Dear Shawn Hafen:

The U.S. Nuclear Regulatory Commission (the Commission) has issued the enclosed Amendment No. 216 to Subsequent Renewed Facility Operating License No. DPR-22, for the Monticello Nuclear Generating Plant. The amendment consists of changes to the technical specifications (TSs) in response to your application dated October 21, 2024, as supplemented February 24, 2025.

The amendment revises the TS actions applicable when a residual heat removal (RHR) shutdown cooling subsystem is inoperable and provides a TS exception to entering Mode 4 if both required RHR shutdown cooling subsystems are inoperable.

A copy of the Safety Evaluation is also enclosed. A Notice of Issuance will be included in the Commissions monthly Federal Register notice.

Sincerely,

/RA/

Beth Wetzel, Project Manager Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-263

Enclosure:

1. Amendment No. 216 to DPR-22

2. Safety Evaluation cc: Listserv

NORTHERN STATES POWER COMPANY DOCKET NO. 50-263 MONTICELLO NUCLEAR GENERATING PLANT, UNIT NO. 1 AMENDMENT TO SUBSEQUENT RENEWED FACILITY OPERATING LICENSE Amendment No. 216 Subsequent Renewed License No. DPR-22

1.

The U.S. Nuclear Regulatory Commission (the Commission) has found that:

A.

The application for amendment by Northern States Power Company (NSPM, the licensee), dated October 21, 2024, and supplemented on February 24, 2025, 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 Title 10 of the Code of Federal Regulations (10 CFR) Chapter I; B.

The facility will operate in conformity with the application, 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.

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 Subsequent Renewed Facility Operating License No. DPR-22 is hereby amended to read as follows:

(2)

Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 216, are hereby incorporated in the subsequent renewed license. NSPM shall operate the facility in accordance with the Technical Specifications.

3.

This license amendment is effective as of its date of issuance and shall be implemented within 120 days of the date of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION Ilka Berrios, Acting Chief Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Attachment:

Changes to the Subsequent Renewed Facility Operating License and Technical Specifications Date of Issuance: April 22, 2025 SCOTT WALL Digitally signed by SCOTT WALL Date: 2025.04.22 12:44:33 -04'00'

ATTACHMENT TO LICENSE AMENDMENT NO. 216 MONTICELLO NUCLEAR GENERATING PLANT, UNIT NO. 1 AMENDMENT TO SUBSEQUENT RENEWED FACILITY OPERATING LICENSE DOCKET NO. 50-263 Subsequent Renewed Facility Operating License No. DPR-22 Replace the following page of the Subsequent Renewed Facility Operating License No. DPR-22 with the attached revised page. The revised page is identified by amendment number and contains marginal lines indicating the area of change.

REMOVE INSERT Page 3 Page 3 Technical Specifications Replace the following pages of 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.

REMOVE INSERT 3.4.7-1 3.4.7-1 3.4.7-2 3.4.7-2 3.4.7-3 3.4.7-3 3.4.8-1 3.4.8-1 3.4.8-2 3.4.8-2

3

3. Pursuant to the Act and 10 CFR Parts 30, 40 and 70, NSPM to receive, possess, and use at any time any byproduct, source and special nuclear material as sealed neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amounts as required;

4. Pursuant to the Act and 10 CFR Parts 30, 40 and 70, NSPM 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

5. Pursuant to the Act and 10 CFR Parts 30 and 70, NSPM to possess, but not separate, such byproduct and special nuclear material as may be produced by operation of the facility.

C. This subsequent 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 NSPM is authorized to operate the facility at steady state reactor core power levels not in excess of 2004 megawatts (thermal).

2. Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 216, are hereby incorporated in the subsequent renewed license. NSPM shall operate the facility in accordance with the Technical Specifications.

3. Physical Protection NSPM shall implement and maintain in effect all provisions of the Commission-approved physical security, guard training and qualification, and safeguards contingency plans including amendments made pursuant to provisions of the Miscellaneous Amendments and Search Requirements revisions to 10 CFR 73.55 (51 FR 27817 and 27822) and to the authority of 10 CFR 50.90 and 10 CFR 50.54(p)(2). The combined set of plans which contain Safeguards Information protected under 10 CFR 73.21, are entitled: "Monticello Nuclear Generating Plant Physical Security, Training and Qualification, and Safeguards Contingency Plan," with revisions submitted through May 12, 2006.

NSPM shall fully implement and maintain in effect all provisions of the Commission-approved Northern States Power Company - Minnesota (NSPM)

RHR Shutdown Cooling System - Hot Shutdown 3.4.7 Monticello 3.4.7-1 Amendment No. 216 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.7 Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown LCO 3.4.7 Two RHR shutdown cooling subsystems shall be OPERABLE, and, with no recirculation pump in operation, at least one RHR shutdown cooling subsystem shall be in operation.

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

1.

Both RHR shutdown cooling subsystems and recirculation pumps may be removed from operation for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months per 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months period.

2.

One RHR shutdown cooling subsystem may be inoperable for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months for the performance of Surveillances.

APPLICABILITY:

MODE 3 with reactor steam dome pressure less than the RHR shutdown cooling supply isolation interlock.

ACTIONS

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

Separate Condition entry is allowed for each RHR shutdown cooling subsystem.

CONDITION REQUIRED ACTION COMPLETION TIME A. One required RHR shutdown cooling subsystem inoperable.

A.1 Verify an alternate method of decay heat removal is available.

1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months AND Once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter B. Required Action and associated Completion Time of Condition A not met.

B.1 Initiate action to restore RHR shutdown cooling subsystem to OPERABLE status.

Immediately

RHR Shutdown Cooling System - Hot Shutdown 3.4.7 Monticello 3.4.7-2 Amendment No. 216 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME C. Two required RHR shutdown cooling subsystems inoperable.

C.1 Verify an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem.

1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months AND Once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter D. Required Action and associated Completion Time of Condition C not met.

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

LCO 3.0.3 and all other LCO Required Actions requiring a MODE change to MODE 4 may be suspended until one RHR shutdown cooling subsystem is restored to OPERABLE status.

D.1 Initiate action to restore one RHR shutdown cooling subsystem to OPERABLE status.

Immediately E. No RHR shutdown cooling subsystem in operation.

AND No recirculation pump in operation.

E.1 Initiate action to restore one RHR shutdown cooling subsystem or one recirculation pump to operation.

AND E.2 Verify reactor coolant circulation by an alternate method.

AND E.3 Monitor reactor coolant temperature and pressure.

Immediately 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery of no reactor coolant circulation AND Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter Once per hour

RHR Shutdown Cooling System - Hot Shutdown 3.4.7 Monticello 3.4.7-3 Amendment No. 216 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.7.1

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

Not required to be met until 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months after reactor steam dome pressure is less than the RHR shutdown cooling supply isolation interlock.

Verify one RHR shutdown cooling subsystem or recirculation pump is operating.

In accordance with the Surveillance Frequency Control Program SR 3.4.7.2

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

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam dome pressure is less than the RHR shutdown cooling supply isolation interlock.

Verify RHR shutdown cooling subsystem locations susceptible to gas accumulation are sufficiently filled with water.

In accordance with the Surveillance Frequency Control Program

RHR Shutdown Cooling System - Cold Shutdown 3.4.8 Monticello 3.4.8-1 Amendment No. 216 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.8 Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown LCO 3.4.8 Two RHR shutdown cooling subsystems shall be OPERABLE, and, with no recirculation pump in operation, at least one RHR shutdown cooling subsystem shall be in operation.

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

1.

Both RHR shutdown cooling subsystems and recirculation pumps may be removed from operation for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months per 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months period.

2.

One RHR shutdown cooling subsystem may be inoperable for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months for the performance of Surveillances.

APPLICABILITY:

MODE 4.

ACTIONS

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

Separate Condition entry is allowed for each RHR shutdown cooling subsystem.

CONDITION REQUIRED ACTION COMPLETION TIME A. One or two RHR shutdown cooling subsystems inoperable.

A.1 Verify an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem.

1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months AND Once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter B. Required Action and associated Completion Time of Condition A not met.

B.1 Initiate action to restore RHR shutdown cooling subsystem(s) to OPERABLE status.

Immediately

RHR Shutdown Cooling System - Cold Shutdown 3.4.8 Monticello 3.4.8-2 Amendment No. 216 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME C. No RHR shutdown cooling subsystem in operation.

AND No recirculation pump in operation.

C.1 Verify reactor coolant circulating by an alternate method.

AND C.2 Monitor reactor coolant temperature and pressure.

1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery of no reactor coolant circulation AND Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter Once per hour SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.8.1 Verify one RHR shutdown cooling subsystem or recirculation pump is operating.

In accordance with the Surveillance Frequency Control Program SR 3.4.8.2 Verify RHR shutdown cooling subsystem locations susceptible to gas accumulation are sufficiently filled with water.

In accordance with the Surveillance Frequency Control Program

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 216 TO SUBSEQUENT RENEWED FACILITY OPERATING LICENSE NO. DPR-22 NORTHERN STATES POWER COMPANY MONTICELLO NUCLEAR GENERATING PLANT, UNIT NO. 1 DOCKET NO. 50-263

1.0 INTRODUCTION

By application dated October 21, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24327A157), as supplemented on February 24, 2025 (ML25059A095), Northern States Power Company (NSPM, the licensee), a Minnesota corporation, doing business as Xcel Energy, submitted a license amendment request (LAR) for Monticello Nuclear Generating Plant (Monticello). The proposed changes would revise technical specification (TS) actions for inoperable residual heat removal (RHR) shutdown cooling subsystems in the RHR shutdown cooling system limiting conditions for operation (LCOs) and would provide a TS exception to entering Mode 4 if both required RHR shutdown cooling subsystems are inoperable.

The proposed changes are based on Technical Specifications Task Force (TSTF) Traveler TSTF-566, Revision 0, Revise Actions for Inoperable RHR Shutdown Cooling Subsystems (ML18019B187), and TSTF-580, Revision 1, Provide Exception from Entering Mode 4 With No Operable RHR Shutdown Cooling (ML21025A232). The U.S. Nuclear Regulatory Commission (NRC, the Commission) issued a final safety evaluation (SE) approving TSTF-566, Revision 0, on February 21, 2019 (ML19028A287), and TSTF-580, Revision 1, on July 11, 2021 (ML21188A227).

The licensee has proposed variations from the TS changes described in TSTF-566, Revision 0, and TSTF-580, Revision 1. The variations are described in section 2.3 of this SE and are evaluated in section 3.3.

The supplement dated February 24, 2025, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the NRC staff's original proposed no significant hazards consideration determination as published in the Federal Register on January 21, 2025 (90 FR 7193).

2.0 REGULATORY EVALUATION

2.1

System Description

Irradiated fuel in the shutdown reactor core generates heat during the decay of fission products and increases the temperature of the reactor coolant. This decay heat must be removed to reduce the temperature of the reactor coolant to less than or equal to 212 degrees Fahrenheit (°F). This decay heat is removed by the RHR shutdown cooling system in preparation for performing refueling or maintenance operations, or for keeping the reactor in the hot shutdown condition or cold shutdown condition.

The two redundant, manually controlled shutdown cooling subsystems of the RHR system provide decay heat removal. Each shutdown cooling system loop consists of two motor-driven pumps, a heat exchanger, and associated piping and valves. Both loops have a common suction from the same recirculation loop. Each pump discharges the reactor coolant, after circulation through the respective heat exchanger, to the reactor via either recirculation loop.

The RHR heat exchangers transfer heat to the RHR service water system. Some piping and heat exchangers, which are passive components, may be common to both subsystems.

TS 3.4.7, Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown, is applicable in Mode 3 with reactor steam dome pressure less than the RHR shutdown cooling supply isolation interlock. TS 3.4.8, Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown, is applicable in Mode 4. The LCO for both requires two operable RHR shutdown cooling subsystems and with no recirculation pump in operation, at least one RHR shutdown cooling subsystem in operation.

2.2 Licensees Proposed Changes The licensee proposed to revise TS actions for inoperable RHR shutdown cooling subsystems in the RHR shutdown cooling system TSs, consistent with TSTF-566, Revision 0, and TSTF-580, Revision 1. The proposed changes would revise TS 3.4.7, Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown, and TS 3.4.8, Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown, for Monticello. The proposed changes are described below.

2.2.1 Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown Required actions for one or two RHR shutdown cooling subsystems inoperable (Condition A) of TS 3.4.7, Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown, require the operators to initiate action to restore RHR shutdown cooling subsystem(s) to operable status (Required Action A.1) immediately, verify an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem (Required Action A.2) within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months , and be in Mode 4 (Required Action A.3) within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

In accordance with NRC staff-approved TSTF-566 and TSTF-580, the licensee proposed changes that would revise TS 3.4.7 for Monticello as follows:

Condition A is changed to be limited to a single inoperable subsystem by revising it to state: One required RHR shutdown cooling subsystem inoperable. Accordingly, a conforming change is proposed to current Required Action A.2.

The Required Action A.1 is moved to new Condition B (as Required Action B.1) and Required Action A.3 is deleted. The LAR also proposed to add a recurring completion time (CT) to current Required Action A.2 of Once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter. The proposed changes also renumber current Required Action A.2 as A.1 since Required Actions A.1 and A.3 are removed from Condition A.

A new Condition B is added to address the situation where the Required Action and associated CT of Condition A are not met. New Condition Bs Required Action B.1 is moved from current Required Action A.1 and requires operators to initiate action to restore the RHR shutdown cooling subsystem to operable status immediately. Because Condition A is proposed to be revised to address a single inoperable RHR shutdown cooling subsystem, Required Action B.1 also only addresses a single RHR shutdown cooling subsystem.

A new Condition C is added which addresses two required RHR shutdown cooling subsystems inoperable with a Required Action C.1 to verify an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem.

The new Condition C Required Action has a CT of 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter.

A new Condition D is added to address situations where new Required Action C.1 and associated CT are not met. New Required Action D.1 requires action be initiated to restore one RHR shutdown cooling subsystem to operable status immediately. Required Action D.1 is modified by a note that states that limiting condition for operation (LCO) 3.0.3 and all other LCO Required Actions requiring a Mode change to Mode 4 may be suspended until one RHR shutdown cooling subsystem is restored to operable status.

Existing Condition B and associated Required Actions are renumbered as E, E.1, E.2, and E.3, respectively, as a result of new Conditions B, C, and D.

2.2.2 Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown Required actions for one or two RHR shutdown cooling subsystems inoperable (Condition A) of TS 3.4.8, Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown, require the operators to verify an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem (Required Action A.1) within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter.

The licensee proposed a new Condition B for when the Required Action and associated CT of Condition A are not met which has a required action (new Required Action B.1) for operators to initiate action to restore RHR shutdown cooling subsystem(s) to operable status immediately.

Because new Condition B is being added, current Condition B and its Required Actions are renamed C, C.1, and C.2, respectively.

2.3 Variations from TSTF-566 and TSTF-580 In addition to the changes proposed consistent with the travelers discussed in section 2.2 of this SE, the licensee proposed the following variations.

2.3.1 Editorial Variations The licensee noted that the Monticello TSs have different numbering than the standard technical specifications (STS). Specifically, STS 3.4.8, Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown, correlates to Monticello TS 3.4.7, Residual Heat Removal (RHR)

Shutdown Cooling System - Hot Shutdown, and STS 3.4.9, Residual Heat Removal (RHR)

Shutdown Cooling System - Cold Shutdown, correlates to Monticello TS 3.4.8, Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown.

2.3.2 Other Variations Traveler TSTF-566 revises the Actions for STS 3.4.8, RHR Shutdown Cooling System - Hot Shutdown. TSTF-580 makes further changes to the Actions of STS 3.4.8 that were revised by TSTF-566. TSTF-580 explains that adoption of the TSTF-580 change is dependent on previous adoption of TSTF-566. The variation is that TSTF-566 has not been adopted, and adoption of both TSTF-566 and TSTF-580 is proposed simultaneously.

2.4 Regulatory Review Under Title 10 of the Code of Federal Regulations (10 CFR) Section 50.92(a), determinations on whether to grant an applied-for license amendment are to be guided by the considerations that govern the issuance of initial licenses to the extent applicable and appropriate. Both the common standards for licenses in 10 CFR 50.40(a) (regarding, among other things, consideration of the operating procedures, the facility and equipment, the use of the facility, and other technical specifications, or the proposals) and those specifically for issuance of operating licenses in 10 CFR 50.57(a)(3), provide that there must be reasonable assurance that the activities at issue will not endanger the health and safety of the public, and that the applicant will comply with the Commissions regulations.

Under 10 CFR 50.90, whenever a holder of a license wishes to amend the license, including TSs in the license, an application for amendment must be filed, fully describing the changes desired.

10 CFR 50.36(a)(1) requires each applicant for a license authorizing operation of a utilization facility to include in the application proposed TSs. The regulation at 10 CFR 50.36(a)(1) states, in part: A summary statement of the bases or reasons for such specifications, other than those covering administrative controls, shall also be included in the application, but shall not become part of the technical specifications.

The regulation at 10 CFR 50.36(b) requires:

Each license authorizing operation of autilization facilitywill include technical specifications. The technical specifications will be derived from the analyses and evaluation included in the safety analysis report, and amendments thereto, submitted pursuant to [10 CFR] 50.34 [Contents of applications; technical information]. The Commission may include such additional technical specifications as the Commission finds appropriate.

The regulation at 10 CFR 50.36(c)(2) requires that TSs include LCOs. Per 10 CFR 50.36(c)(2)(i), LCOs are the lowest functional capability or performance levels of equipment required for safe operation of the facility. The regulation also requires that when an LCO of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the [TSs] until the condition can be met.

The regulation at 10 CFR 50.40(a) states, in part, that the TSs shall provide reasonable assurancethat the health and safety of the public will not be endangered.

The NRC staffs guidance for the review of TSs is in Chapter 16.0, Technical Specifications, of NUREG-0800, Revision 3, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR [Light-Water Reactor] Edition (SRP), March 2010 (ML100351425). As described therein, as part of the regulatory standardization effort, the NRC staff has prepared STSs for each of the LWR nuclear designs. Accordingly, the staffs review includes consideration of whether the proposed changes are consistent with the NRC Standard Technical Specifications, General Electric BWR/4 Plants, NUREG-1433, Volume 1, Specifications, and Volume 2, Bases, Revision 5.0, September 2021 (ML21272A357 and ML21272A358, respectively), as modified by NRC-approved travelers.

3.0 TECHNICAL EVALUATION

In accordance with the SRP Chapter 16.0, the NRC staff determined that the STS changes approved in TSTF-566 and TSTF-580 are applicable to Monticello because Monticello is a boiling-water reactor (BWR) design plant, and the NRC staff approved TSTF-566 and TSTF-580 changes for BWR designs. The proposed changes to the Monticello TSs are consistent with the changes found acceptable in TSTF-566 and TSTF-580 and are discussed below.

3.1 Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown The licensee proposed to modify TS 3.4.7, Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown. The technical evaluation of each change follows.

3.1.1 Evaluation of Changes to Condition A The licensee proposed to add a recurring CT to current Required Action A.2 of once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter. Current Required Action A.2 requires verification that an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months . The NRC staff finds this change acceptable because it requires continuous verification of alternate methods of decay heat removal every 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , provides assurance of continued heat removal capability, and is consistent with the changes found acceptable in TSTF-566.

The licensee also proposed to delete current Required Action A.3, which requires the plant to be in Mode 4 within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months when one or two RHR shutdown cooling subsystems are inoperable.

Current Required Action A.3 requires operators to reduce the reactor coolant system temperature to the point where Mode 4 is entered, due to the potentially reduced reliability of the alternate methods of decay heat removal. However, if there is no operable RHR shutdown cooling subsystem and the plant is in a period of high decay heat load, it may not be possible to reduce the average reactor coolant system temperature to the Mode 4 entry condition (less than or equal to 212 °F) within the CT. In addition, in a typical BWR design, the RHR shutdown cooling system has a heat rejection capability many times greater than alternate methods available. Therefore, for periods in which there is high decay heat load, the BWR design does not include any system which can satisfy Required Action A.3. The NRC staff finds the deletion of current Required Action A.3 acceptable because, with reactor steam dome pressure less than the RHR shutdown cooling supply isolation interlock, the remaining required action will ensure that fission product decay heat and other residual heat from the reactor core is transferred at a rate such that the specified acceptable fuel design limits and the design conditions of the reactor coolant pressure boundary are not exceeded. This change is consistent with the changes found acceptable in TSTF-566.

Condition A is changed to be limited to a single inoperable subsystem by revising it to state:

One required RHR shutdown cooling subsystem inoperable. Accordingly, a conforming change is made to proposed Required Action A.1. The NRC staff finds this change acceptable because it is a conforming change that is consistent with the changes found acceptable in TSTF-580.

Current Required Action A.2 is renumbered as A.1, since Required Actions A.1 and A.3 are removed from Condition A. The NRC staff finds this change acceptable since it provides the correct number sequence, and this change is consistent with the changes found acceptable in TSTF-566.

3.1.2 Evaluation of New Condition B The licensee proposed a new Condition B for when the Required Action and associated CT of Condition A are not met. New Condition Bs Required Action, B.1, is moved from current Required Action A.1 and requires operators to initiate action to restore RHR shutdown cooling subsystems to operable status immediately. The NRC staff finds that relocating the required action from A.1 to new Required Action B.1 is acceptable because other ways of removing decay heat are available, such as the condensate/feed and main steam systems, the reactor water cleanup system, or an inoperable but functional RHR shutdown cooling subsystem. Also, this change is consistent with the changes found acceptable in TSTF-566.

New Condition B addresses situations when Required Action and associated CT of Condition A are not met. Because Condition A now addresses a single inoperable RHR shutdown cooling subsystem, conforming changes were made to Required Action B.1 (formerly Required Action A.1) to address a single RHR shutdown cooling subsystem. The NRC staff finds this change is acceptable because it is consistent with the changes found acceptable in TSTF-580.

If an alternate method cannot be established (Condition A), new Condition B requires the licensee to immediately initiate action to restore the inoperable RHR shutdown cooling subsystem to operable status. The CT term immediately is defined in section 1.3 of the Monticello TSs as, the Required Action should be pursued without delay and in a controlled manner. New Required Action B.1 continues to apply until the inoperable RHR shutdown cooling subsystem is restored to operable status, an alternate decay heat removal method is available, or the specification is exited.

The NRC staff finds new Condition B with its associated Required Action and CT acceptable because it provides an appropriate terminal action for when an alternate method of decay heat removal is not available within the CT established in Condition A. In addition, new Required Action B.1 will restore redundant decay heat removal paths, and the immediate CT reflects the importance of maintaining the availability of two paths for heat removal. This change is also consistent with the changes found acceptable in TSTF-566.

3.1.3 Evaluation of New Condition C A new Condition C is added which addresses two required RHR shutdown cooling subsystems inoperable with a Required Action C.1 to verify that an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem. The new Condition C Required Action has a CT of 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter.

The NRC staff finds this change acceptable because it requires verification of alternate methods of decay heat removal within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months and every 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months thereafter, which provides assurance of continued heat removal capability, and is consistent with the changes found acceptable in TSTF-580.

3.1.4 Evaluation of New Condition D A new Condition D is added to address situations when new Required Action C.1 and associated CT are not met. New Required Action D.1 requires action be initiated to restore one RHR shutdown cooling subsystem to operable status immediately. Required Action D.1 is modified by a note that states that LCO 3.0.3 and all other LCO Required Actions requiring a Mode change to Mode 4 may be suspended until one RHR shutdown cooling subsystem is restored to operable status.

In the SE for TSTF-580, the NRC staff concluded that TSTF-580 changes to STS 3.4.8, Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown, are acceptable because, without an operable RHR shutdown cooling subsystem and in a period of high decay heat load, it may not be possible to reduce the reactor coolant system temperature to the Mode 4 entry condition within the CT. Under this condition, remaining in Mode 3 allows fission product decay heat and other residual heat from the reactor core to be transferred at a rate such that the specified acceptable fuel design limits and the design conditions of the reactor coolant pressure boundary will not be exceeded. The CT reflects the importance of restoring a normal path for heat removal.

The NRC staff finds new Condition D with its associated Required Action and CT acceptable because it provides an appropriate terminal action for when alternate methods of decay heat removal are not available within the CT established in Condition C. In addition, new Required Action D.1 will restore one RHR path and the immediate CT reflects the importance of maintaining the availability of a path for heat removal. This change is also consistent with the changes found acceptable in TSTF-580.

3.1.5 Evaluation of Changes to Existing Condition B (Renamed E)

Current Condition B and its Required Actions were renamed E, E.1, E.2, and E.3, respectively, since new Conditions B, C, and D were added. The NRC staff finds these changes acceptable since they provide the correct number sequence and are consistent with the changes found acceptable in TSTF-566 and TSTF-580.

3.1.6 Conclusion of Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown The NRC staff determined that the proposed changes are consistent with the changes previously found acceptable in TSTF-566 and TSTF-580. The NRC staff finds the proposed changes are acceptable since the TSs continue to meet the requirements of 10 CFR 50.40(a) by providing reasonable assurance that the health and safety of the public will not be endangered. The NRC staff also finds the requirements of 10 CFR 50.36(c)(2)(i) continue to be met by providing appropriate remedial actions when an LCO is not met.

3.2 Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown The licensee proposed to modify TS 3.4.8, Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown. The technical evaluation of each change follows.

3.2.1 Evaluation of New Condition B The licensee proposed a new Condition B for when the Required Action and associated CT of Condition A are not met. If an alternate method cannot be established (Condition A), new Condition B requires the licensee to immediately initiate action to restore the inoperable RHR shutdown cooling subsystem(s) to operable status. The CT term immediately is defined in section 1.3 of the Monticello TSs as, the Required Action should be pursued without delay and in a controlled manner. New Required Action B.1 continues to apply until the inoperable RHR shutdown cooling subsystems are restored to operable status, an alternate decay heat removal method is established, or the specification is exited.

The NRC staff finds new Condition B with its associated Required Action and CT acceptable because it provides an appropriate terminal action for when an alternate method cannot be established within the CT established in Condition A. In addition, new Required Action B.1 will restore redundant decay heat removal paths, and the immediate CT reflects the importance of maintaining the availability of two paths for heat removal. This change is also consistent with the changes found acceptable in TSTF-566.

3.2.2 Evaluation of Changes to Existing Condition B Current Condition B and its Required Actions were renamed C, C.1, and C.2, respectively, since new Condition B was added. The NRC staff finds this change acceptable since it provides the correct number sequence. This change is also consistent with the changes found acceptable in TSTF-566.

3.2.3 Conclusion of Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown The NRC staff determined that the proposed changes are consistent with the changes previously found acceptable in TSTF-566. The NRC staff finds the proposed changes are acceptable since the TSs continue to meet the requirements of 10 CFR 50.40(a) by providing reasonable assurance that the health and safety of the public will not be endangered. The NRC staff also finds the requirements of 10 CFR 50.36(c)(2)(i) continue to be met by providing appropriate remedial actions when an LCO is not met.

3.3 Additional Proposed TS Changes 3.3.1 Editorial Changes The licensee noted that Monticello TSs have different numbering than the STS. The NRC staff finds that the different TS numbering changes are acceptable because they do not substantively alter TS requirements.

3.3.2 Other Variations Traveler TSTF-566 revises the Actions for STS 3.4.8, RHR Shutdown Cooling System - Hot Shutdown. TSTF-580 makes further changes to the Actions of STS 3.4.8 that were revised by TSTF-566, which is consistent with the staff's approval of TSTF-580. TSTF-580 explains that adoption of this change is dependent on previous adoption of TSTF-566. The NRC staff finds that adoption of both travelers simultaneously as proposed in the LAR satisfies this TSTF-580 requirement because the changes included in TSTF-566 are adopted and the adoption of both travelers simultaneously is, therefore, acceptable.

3.4 TS Change Consistency The NRC staff reviewed the proposed TS changes for technical clarity and consistency with the existing requirements for customary terminology and formatting. The NRC staff finds that the proposed changes are consistent with Chapter 16.0 of the SRP and are, therefore, acceptable.

4.0 STATE CONSULTATION

In accordance with the Commissions regulations, the Minnesota State official was notified of the proposed issuance of the amendments on March 18, 2025. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

The amendments change requirements 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 amendments involve 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 NRC has previously issued a proposed finding that the amendments involve no significant hazards consideration in the Federal Register on January 21, 2025 (90 FR 7193), and there has been no public comment on such finding. Accordingly, the amendments meet 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 amendments.

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 Commissions regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributor: C. Ashley, NRR Date of Issuance: April 22, 2025

ML25086A138 OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DSS/STSB/BC NAME BWetzel SRohrer SMehta DATE 3/28/2025 3/27/2025 2/11/2025 OFFICE OGC (NLO)

NRR/DORL/LPL3/BC NRR/DORL/LPL3/PM NAME CRyan IBerrios (SWall, for)

BWetzel DATE 4/11/2025 4/22/2025 4/22/2025

v t e Letter Sequence Approval
EPID:L-2024-LLA-0154, TSTF-580 (Open)
Initiation Request Acceptance Supplement Administration Questions Answers Results Approval Other:
MONTHYEAR2024-12-12 [Table View]

ML25086A138