ML24134A178

Issuance of Amendment No. 276 Revision to Technical Specification 3.8.3, Diesel Fuel Oil, Lube Oil and Starting Air, to Allow for Cleaning, Inspection and Any Needed Repairs During Refuel Outage 33

ML24134A178
Person / Time
Site:	Cooper
Issue date:	07/03/2024
From:	Byrd T Plant Licensing Branch IV
To:	Dent J Nebraska Public Power District (NPPD)
Wengert T, NRR/DORL/LPLIV, 415-4037
References
EPID L-2023-LLA-0126
Download: ML24134A178 (1)

Text

July 3, 2024

John Dent, Jr.

Executive Vice President and Chief Nuclear Officer Nebraska Public Power District Cooper Nuclear Station 72676 648A Avenue P.O. Box 98 Brownville, NE 68321

SUBJECT:

COOPER NUCLEAR STATION - ISSUANCE OF AMENDMENT NO. 276 REGARDING REVISION TO TECHNICAL SPECIFICATION 3.8.3, DIESEL FUEL OIL, LUBE OIL, AND STARTING AIR, TO ALLOW FOR CLEANING, INSPECTION AND ANY NEEDED REPAIRS DURING REFUEL OUTAGE 33 (EPID L-2023-LLA-0126)

Dear John Dent:

The U.S. Nuclear Regulatory Commission (the Commission) has issued the enclosed Amendment No. 276 to Renewed Facility Operating License No. DPR-46 for Cooper Nuclear Station (Cooper). The amendment consists of changes to the technical specifications (TSs) in response to your application dated September 6, 2023 (Agencywide Documents Access and Management System (ADAMS) Accession No. M L23249A134), as supplemented by letter dated March 8, 2024 (ML24071A140).

The amendment modifies TS 3.8.3, Diesel Fuel Oil, Lube Oil, and Starting Air, to allow the use of temporary fuel oil storage tanks to supplement the required fuel inventory used by the emergency diesel generators. This TS change is only applicable for the 2024 Refuel Outage 33 while in Modes 4 or 5 to allow cleaning, inspection, and repair of the permanent diesel fuel oil storage tanks.

J. Dent, Jr.

A copy of the related safety evaluation is also enclosed. Notice of Issuance will be included in the Commissions monthly Federal Register notice.

Sincerely,

/RA/

Thomas J. Byrd, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Docket No. 50-298

Enclosures:

1. Amendment No. 276 to DPR-46

2. Safety Evaluation

cc: Listserv

NEBRASKA PUBLIC POWER DISTRICT

DOCKET NO. 50-298

COOPER NUCLEAR STATION

AMENDMENT TO RENEWED FACI LITY OPERATING LICENSE

Amendment No. 276 Renewed License No. DPR-46

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

A. The application for amendment by Nebraska Public Power District (the licensee) dated September 6, 2023, as supplemented by letter dated March 8, 2024, 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, 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. DPR-46 is hereby amended to read as follows:

(2) Technical Specifications

The Technical Specifications contained in Appendix A as revised through Amendment No. 276, are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications.

3. The license amendment is effective as of its date of issuance and shall be implemented within 60 days of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION

Jennivine K. Rankin, Chief Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Attachment:

Changes to Renewed Facility Operating License No. DPR-46 and the Technical Specifications

Date of Issuance: July 3, 2024

ATTACHMENT TO LICENSE AMENDMENT NO. 276

RENEWED FACILITY OPERATING LICENSE NO. DPR-46

COOPER NUCLEAR STATION

DOCKET NO. 50-298

Replace the following pages of Renewed Facility Operating License No. DPR-46 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

Technical Specifications

REMOVE INSERT 3.8-13 3.8-13 3.8-14 3.8-14

(5) 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 operation of the facility.

C. This license shall be deemed to contain and is subject to the conditions specified in the following Commission regulations in 10 CFR Chapter I: Part 20, Section 30.34 of Part 30, Section 40.41 of Part 40, Sections 50.54 and 50.59 of Part 50, and Section 70.32 of Part 70; 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 licensee is authorized to operate the facility at steady state reactor core power levels not in excess of 2419 megawatts (thermal).

(2) Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 276, are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications.

(3) Physical Protection The licensee shall fully implement and maintain in effect all provisions of the Commission-approved physical security, 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). The combined set of plans, which contain Safeguards Information protected under 10 CFR 73.21, are entitled: Cooper Nuclear Station Safeguards Plan, submitted by letter dated May 17, 2006.

NPPD shall fully implement and maintain in effect all provisions of the Commission-approved cyber security plan (CSP), including changes made pursuant to the authority of 10 CFR 50.90 and 10 CFR 50.54(p). The NPPD CSP was approved by License Amendment No. 238 as supplemented by changes approved by License Amendments 244 and 249.

(4) Fire Protection NPPD shall implement and maintain in e ffect all provisions of the approved fire protection program that comply with 10 CFR 50.48(a) and 10 CFR 50.48(c), as specified in the license amendment request dated April 24, 2012 (and supplements dated July 12, 2012, January 14, 2013, February 12, 2013, March 13, 2013, June 13, 2013, December 12, 2013, January 17, 2014, February 18, 2014, and April 11, 2014), and as approved in the safety evaluation dated April 29, 2014.

Except where NRC approval for changes or deviations is required by 10 CFR 50.48(c), and provided no other regulation, technical specification, license condition or requirement would require prior NRC approval, the licensee may make changes to the fire protection program without prior approval of the Commission if

Amendment No. 276 Diesel Fuel Oil, Lube Oil, and Starting Air 3.8.3 3.8 ELECTRICAL POWER SYSTEMS 3.8.3 Diesel Fuel Oil, Lube Oil, and Starting Air LCO 3.8.3 The stored diesel fuel oil, lube oil, and starting air subsystem shall be within limits for each required diesel generator (DG).

APPLICABILITY: When associated DG is required to be OPERABLE.

ACTIONS

---

NO TES ----------------------------------------------------------

1.Separate Condition entry is allowed for each DG, except for Conditions A, C, and D.

2.During Refuel Outage 33, a diesel fuel oil storage tank (FOST) may be made inoperable and drained to support cleaning, inspection, testing, and associated repair activities without entering Conditions A and F, provided the following are satisfied:

a.Equipment (temporary transfer pump, hoses, and appropriate fittings) capable of supplying fuel oil to the in-service permanent tank aligned to the operable DG must be available.

b.Verify once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> that the FOSTs and temporary storage tanks combined contain at least a 7-day supply of fuel oil.

c.The compensatory measures contained in Attachment 2 of Nebraska Public Power District letter NLS2023029 are met.

d.FOSTs must be restored within 14 days.

If Notes 2.a through 2.d are not satisfied, enter Condition F.

Each tank will be drained separately during associated divisional window. This temporary note is applicable only during Refuel Outage 33 while in MODES 4 or 5.

CONDITION A.Fuel oil level less than a 7 A.1 day supply and greater than a 6 day supply in storage tanks.

Cooper REQUIRED ACTION Restore fuel oil level to within limits.

3.8-13 COMPLETION TIME 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />

( continued)

Amendment No. 276 ACTIONS ( continued)

CONDITION B.One or more DGs with lube oil inventory less than a 7 day supply and greater than a 6 day supply.

C.Stored fuel oil total particulates not within limit.

D.New fuel oil properties not within limits.

E.One or more DGs with starting air receiver pressure

< 200 psig and 125 psig.

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

OR One or more DGs with diesel fuel oil, lube oil, or starting air subsystem not within limits for reasons other than Condition A, B, C, D, or E.

Cooper B.1 C.1 D.1 E.1 F.1Diesel Fuel Oil, Lube Oil, and Starting Air 3.8.3 REQUIRED ACTION COMPLETION TIME Restore lube oil inventory 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> to within limits.

Restore stored fuel oil total 7 days particulates to within limit.

Restore stored fuel oil 30 days properties to within limits.

Restore starting air 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> receiver pressure to 200 psig.

Declare associated DG( s) Immediately inoperable.

3.8-14 Amendment No. 276 SAFETY EVALUATION BY THE OFFICE NUCLEAR REACTOR REGULATION

RELATED TO AMENDMENT NO. 276TO

RENEWED FACILITY OPERATING LICENSE NO. DPR-46

NEBRASKA PUBLIC POWER DISTRICT

COOPER NUCLEAR STATION

DOCKET NO. 50-298

1.0 INTRODUCTION

By letter dated September 6, 2023 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML23249A134), as supplemented by letter dated March 8, 2024 (ML24071A140), Nebraska Public Power District (NPPD, the licensee) submitted a license amendment request (LAR) requesting changes to the technical specifications (TSs) for Cooper Nuclear Station (Cooper or CNS).

The proposed amendment would modify TS 3.8.3 Diesel Fuel Oil, Lube Oil, and Starting Air, to allow the use of temporary fuel oil storage tanks to supplement the required fuel inventory used by the emergency diesel generators. This TS change would be applicable during the 2024 Refuel Outage 33 while in Modes 4 or 5 to allow cleaning, inspection, and any needed repairs of the permanent diesel generator storage tanks.

The supplemental letter dated March 8, 2024, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the NRC or the Commission) staff s original proposed no significant hazards consideration determination as published in the Federal Register on November 28, 2023 (88 FR 83168).

2.0 REGULATORY EVALUATION

2.1 System Description

Coopers standby alternating current (AC) power system is powered by two independent diesel generators (DG) capable of an automatic start at any time and capable of continued operation at rated load, voltage, and frequency until manually stopped. DG auxiliary and support subsystems such as fuel oil and fuel oil transfer, lubricating oil, jacket water, service water, and starting air are required for operation of each DG.

The Cooper diesel fuel support system consists of two interconnected permanent diesel generator fuel oil (DGFO ) storage tanks, each with capacity for approximately four days of

Enclosure 2

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diesel engine operation. Both DGFO storage tanks, each with its own transfer pump and piping connections, combined can provide sufficient fuel for seven days of operation of one DG unit under postulated accident conditions. The fuel oil volume equivalent to the TS required 7-day supply is 49,500 gallons. Each DG unit is supplied from its own fuel oil day tank which provides enough fuel to allow a minimum of 3.9 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br /> of full load operation. The unit day tanks are supplied from the two DGFO storage tanks and cross-ties are provided such that both day tanks can be supplied from either of the DGFO storage tanks.

The specific DG fuel oil volumes contained in the DGFO storage tanks necessary to ensure that DG run-duration requirements are met, are calculated using Section 5.4 of American National Standards Institute (ANSI) N195-1976, "Fuel Oil Systems for Standby Diesel Generators," and are based on applying the conser vative assumption that the DG is operated continuously for 7 days at its rated capacity. This fuel oil calculation methodology is one of two approved methods specified in Regulatory Guide (RG) 1.137, Revision 1, "Fuel Oil Systems for Standby Diesel Generators" (ML 003740180)

The normal fuel storage system consists of:

• Two combined DGFO storage tanks (30,000 gallons each) which together contain sufficient capacity to provide approximately 7 days (i.e., 49,500 gallons) of operation at rated load.

• Each DG unit is supplied from its own fuel oil day tank (2,500 gallons) located within the Diesel Generator Building. Each day tank provides enough fuel to allow a minimum of 3.9 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br /> of full load operation.

As indicated above, the operable DG is supported by an in-service diesel fuel oil system consisting of DGFO storage tanks and divisional fuel oil transfer pumps connected to the associated divisional DG day tank located within the Diesel Generator Building. The permanent DGFO storage tanks and transfer pumps are located underground, therefore protected from severe weather hazards.

In Modes 4 and 5, Cooper limiting condition for operation 3.8.2, AC [alternating current]

Sources - Shutdown, requires, in part, one of two operable DGs capable of supplying one division of the onsite Class 1E AC electrical power distribution subsystem.

2.1.1 Reason for the Proposed Change

The DGFO storage tanks require periodic cleaning and examination under the License Renewal Buried Piping and Tanks Inspection Program (ADAMS Accession N o. ML101310605) and Diesel Fuel Monitoring Program (ADAMS Accession No. ML083030225) to manage aging effects regarding the potential for loss of material due to various forms of corrosion.

The licensee plans to perform the next DGFO storage tank internal inspection during Refuel Outage 33. Activities to drain, clean, inspect and potentially repair the DGFO storage tanks will reduce the stored diesel fuel oil in the permanent storage tanks to below the current Cooper TS limits for an operable DG. The licensee estimates the required draining, cleaning, inspection, and refilling of both DGFO storage tanks will take approximately fourteen days. The requested change would support completion of the required DGFO storage tank examinations concurrent with the planned Refuel Outage 33.

2.1.2 Description of the Proposed TS Change

The proposed changes would insert a temporary note in the TS 3.8.3 Actions table.

Proposed Actions table note 2 would state:

2. During Refuel Outage 33, a diesel fuel oil storage tank (FOST) may be made inoperable and drained to support cleaning, inspection, testing, and associated repair activities without entering Conditions A and F, provided the following are satisfied:

a. Equipment (temporary transfer pump, hoses, and appropriate fittings) capable of supplying fuel oil to the in-service permanent tank aligned to the operable DG must be available.

b. Verify once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> that the FOSTs and temporary storage tanks combined contain at least a 7-day supply of fuel oil.

c. The compensatory measures contained in Attachment 2 of Nebraska Public Power District letter NLS2023029 are met.

d. FOSTs must be restored within 14 days.

If Notes 2.a through 2.d are not satisfied, enter Condition F.

Each tank will be drained separately during associated divisional window. This temporary note is applicable only during Refuel Outage 33 while in MODES 4 or 5.

In addition to the note above, the existing Actions table note would be numbered 1.

2.2 Regulatory Requirements and Guidance Documents

2.2.1 Regulatory Requirements

Under 10 CFR 50.92(a), in determining whether an amendment to a license will be issued, the NRC is guided by the considerations that govern the issuance of initial licenses to the extent applicable and appropriate. The common standards for licenses in 10 CFR 50.40(a),

and those specifically for issuance of operating licenses in 10 CFR 50.57(a)(3), provide that the NRC must find reasonable assurance that the activities authorized can be conducted without endangering the health and safety of the public, and that such activities will be conducted in compliance with the Commissions regulations.

Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36, Technical specifications, establishes the regulatory requirements related to the contents of the TSs. In accordance with 10 CFR 50.36, TSs for operating reactors are required to include items in the following five specific categories related to station operation: (1) safety limits, limiting safety system settings, and limiting control settings; (2) limiting conditions for operation (LCO s); (3) surveillance requirements (SRs); (4) design features; and (5) administrative controls.

The regulation in 10 CFR 50.36(c)(2) states, in part, that,

Limiting conditions for operation are the lowest functional capability or performance levels of equipment required for safe operation of the facility. When a limiting condition for operation of a nuclear reactor is not met, the licensee shall

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shut down the reactor or follow any remedial action permitted by the technical specifications until the condition can be met.

Additionally, the NRC staffs technical evaluation considers whether the safety and security measures, as stated in the LAR dated September 6, 2023, provide a level of protection commensurate with the protection measures required in 10 CFR 73.55, Requirements for physical protection of licensed activities in nuclear power reactors against radiological sabotage; 10 CFR 73.58, Safety/security interface requirements for nuclear power reactors ;

and Appendix C to 10 CFR Part 73, Licensee Safeguards Contingency Plans,

Section II.B.3.c.(v).

The regulations in 10 CFR 73.55(b)(3) state that [t]he physical protection program must be designed to prevent significant core damage and spent fuel sabotage. Specifically, the program must:

(i) Ensure that the capabilities to detect, assess, interdict, and neutralize threats up to and including the design basis threat of radiological sabotage as stated in § 73.1, are maintained at all times.

(ii) Provide defense-in -depth through the integration of systems, technologies, programs, equipment, supporting processes, and implementing procedures as needed to ensure the effectiveness of the physical protection program.

The regulation in 10 CFR 73.55(e)(9)(ii), states, in part, that [ t]he licensee shall protect all vital area access portals and vital area emergency exits with intrusion detection equipment and locking devices...

The regulation in 10 CFR 73.55(f)(4), states, in part that [ t]he licensee shall implement a process for the oversight of target set equipment and systems to ensure that changes to the configuration of the identified equipment and systems are considered in the licensees protective strategy.

The regulations in 10 CFR 73.55(o), Compensatory measures, state, in part, that the licensee shall identify criteria and measures to compensate for degraded or inoperable equipment, systems, and components. The compensatory measures must provide a level of protection that is equivalent to the protections that was provided by the degra ded or inoperable equipment, system or components and must be implemented within specific time frames.

The regulation in 10 CFR 73.58(a) requires that [e]ach operating nuclear power reactor licensee with a license issued under part 50 or 52 of this chapter shall comply with the requirements of this section.

The regulation in 10 CFR 73.58(b) requires that [t]he licensee shall assess and manage the potential adverse effects on safety and security, including the site emergency plan, before implementing changes to plant configurations, facilities conditions, or security.

The regulation in 10 CFR 73.58(c) requires that [t]he scope of changes to be assessed and managed must include planned and emergent activities (such as, but not limited to, physical modifications, procedural changes, changes to operator actions or security assignments, maintenance activities, system reconfiguration, access modification or restrictions, and changes to the security plan and its implementation).

The regulation in 10 CFR 73.58(d) states that [w]here potential conflicts are identified, the licensee shall communicate them to appropriate licensee personnel and take compensatory and/or mitigative actions to maintain safety and security under applicable Commission regulations, requirements, and license conditions.

Appendix C to 10 CFR Part 73, Section II.B.3.c (v), requires that [l] icensees shall develop, implement, and maintain a written protective strategy to be documented in procedures that describe in detail the physical protection measures, security systems and deployment of the armed response team relative to site specific conditions, to include but not be limited to, facility layout, and the location of target set equipment and elements. The protective strategy should support the general goals, operational concepts, and performance objectives identified in the licensees safeguards contingency plan.

2.1.2 Regulatory Guidance

Chapter 18, Human Factors Engineering, of NUREG-0800, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR [Light-Water Reactor]

Edition (SRP), Revision 3, December 2016 (ML16125A114), describes the guidance used by NRC staff to conduct regulatory reviews of LARs that address human factors topics. It directs staff to applicable review criteria such as those included in NUREG-1764, Guidance for the Review of Changes to Human Actions (ML072640413).

NUREG-1764, Rev ision 1, September 2007, describes how to assess changes to manual operator actions. It provides a risk-informed process to determine the level of NRC review necessary and provides the acceptance criteria for each level of review.

Regulatory Guide (RG) 5.74, Managing the Safety/Security Interface, Revision 1, April 2015, (ML14323A549), describes a method that the NRC staff considers acceptable for nuclear power plant licensees to assess and manage changes to safety and security activities to prevent or mitigate potential adverse effects that could negatively impact either plant safety or security at power reactors.

RG 5.76, Physical Protection Programs at Nuclear Power Reactors, Revision 1, November 2020; and RG 5.54, Standard Format and Content of Safeguards Contingency Plans for Nuclear Power Plants, Revision 1, June 2009 (both not publicly available, s afeguards information (SGI)), provides guidance on meeting the requirements related to the layers of defense and defense-in -depth. RG 5.76 also describes interlocking/overlapping fields -of-fire.

3.0 TECHNICAL EVALUATION

3.1 Technical Specifications and Plant Systems Evaluation

The Cooper DGFO system consists of two interconnected permanent DGFO storage tanks, each with capacity for approximately four days of diesel engine operation. DGFO storage tanks combined contain sufficient fuel for the TS required seven days operation of one DG at its rated continuous load. Each DG has a unit fuel day tank with fuel supplied from the combined two main fuel storage tanks.

The licensee stated in the LAR, as supplemented, that during the inspection process each of the two underground DGFO storage tanks will be taken out-of-service one at a time and drained to

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perform license renewal committed inspections. Each DGFO storage tank will be drained separately and at least one DGFO storage tank will remain available during the storage tank inspection evolution. Additionally, both qualified offsite power sources are planned to remain operable during the tank cleaning evolution.

The licensee stated that the plan is to isolate the out-of-service storage tank and transfer pump from the system during each individual tank cleaning and inspection process. Part of the fuel will be transferred from the isolated tank to the in-service permanent DGFO storage tank to establish a minimum volume which supports at least four days of DG operation at full load. An additional three days of fuel oil will be maintained in temporary diesel storage tanks with associated fuel transfer equipment located inside the p rotected area. The operable DG will be supported by an in-service diesel fuel oil system consisting of one permanent safety related DGFO storage tank and one divisional fuel oil transfer pump connected to the associated divisional day tank located within the Diesel Generator Building.

In the letter dated March 8, 2024, NPPD proposed a TS note that states a FOST may be made inoperable and drained to support cleaning, inspection, testing, and associated repair activities and must be restored within 14 days. This temporary note is applicable only during Refuel Outage 33 while in MODES 4 or 5.

The licensee stated in the LAR, as supplemented, that the temporary configuration will be provided to support the DG fuel inventory requirements. This is performed by utilizing the following:

1. The existing in-service diesel fuel oil system consisting of one permanent safety related DGFO storage tank and one divisional fuel oil transfer pump connected to the associated divisional DG day tank. This configuration will maintain at least 4 days of diesel fuel oil.

2. The existing safety-related DG day tank located within the Diesel Generator Building; and

3. Double-walled temporary fuel oil storage tanks (typically rated at 18,000 gallons each) installed onsite, referred to as FRAC tanks and associated fuel oil transfer equipment that supplement the DGFO storage tank as the additional DG day tank supply source.

The combination of fuel tanks provides the requisite 7-day supply of fuel oil to the required DG day tank during the maintenance evolution. Prior to removing either permanent DGFO storage tank from service, NPPD will perform compensatory measures to verify the temporary fuel oil storage system is staged and can contain and provide at least a 3-day supply of fuel oil to the permanent DGFO storage tank. In addition, NPPD is required to verify once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> that the in-service DGFO storage tank and temporary storage tanks combined contain at least a 7-day supply of fuel. If the temporary FRAC tanks were themselves to be impacted there are other sources of diesel fuel oil available onsite, as defense-in -depth measures described in Section 3.4 of the application.

The proposed note incorporated into TS 3.8.3 Actions table would allow each of the main FOST to be inoperable and drained for up to 14 days. The note would require that if the FOST is not restored within 14 days, or if Notes 2.a through 2.d are not satisfied, the licensee must enter TS 3.8.3 Condition F and immediately declare the associated DG inoperable.

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The TS 3.8.3 note specifies the appropriate TS actions applicable during the FOST inspection evolution. The application requires the following actions be taken during the FOST cleaning activity:

a. Equipment (temporary transfer pump, hoses. and appropriate fittings) capable of supplying fuel oil to the in-service permanent tank aligned to the operable DG must be available.

b. Verify once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> that the FOSTs and temporary storage tanks combined contain at least a 7-day supply of fuel oil.

c. The compensatory measures contained in Attachment 2 of Nebraska Public Power District letter NLS2023029 are met.

d. FOSTs must be restored within 14 days.

As indicated in item c. above, compensatory measures specified within Attachment 2 of letter NLS2023029 (i.e., the application) are incorporated into TS 3.8.3 by reference. This means that the compensatory measures are requirements during performance of the DGFO storage tank inspection evolution. Attachment 2 of the application contains a table with the following TS compensatory measures:

1. Work instructions to restore off-loaded fuel oil to the permanent diesel generator fuel oil (DGFO) storage tank, in the event of a DG start, and work instructions to accomplish the defense in depth measures are incorporated into an approved procedure.

2. Training, briefings, and walkthroughs, in accordance with station procedures, to implement the work instructions are provided.

3. Verify the temporary fuel oil storage system is staged and can contain at least a 3-day supply of fuel oil to the permanent DGFO storage tank.

4. Verify the in-service fuel oil storage tank transferring fuel oil from contains at least a 4-day supply of fuel oil.

5. Verify both qualified offsite power sources operable.

6. Evaluate weather forecast for thunderstorm warnings and tornado warnings.

7. Elective maintenance and testing that affects operability of the required DG are not permitted.

8. Personnel that have been briefed on the procedures are continuously available to implement actions necessary to ensure transfer of fuel oil, as needed, in the case of a DG start.

9. Verify the DGFO storage tanks and temporary storage tanks combined contain at least a 7-day supply of fuel oil.

This one-time TS change would be applicable only during the 2024 Refuel Outage 33 with the reactor in Mode 4 or 5. Once the DGFO storage tanks are restored to operable status (or the 14-day completion time for each FOST has expired), the conditions specified in TS note to the ACTIONS table would no longer be applicable.

With one inoperable DGFO storage tank, the licensee would maintain one permanent DGFO storage tank in-service at all times, maintain additional temporary storage tanks and fuel oil transfer equipment, and implement compensatory measures to support one required DG operable and ensure shutdown risk is maintained at an acceptable level during the DGFO storage tank inspection evolution.

The proposed change has no effect on the design of the DG s and the proposed actions will ensure that the DG function is maintained during the inspection evolution. The NRC staff considers the proposed compensatory measures as adequate, describing reasonable actions during the required draining, inspecting/cleaning, and refilling of the DGFO storage tanks. The NRC staff finds the compensatory actions to be of an appropriate scope as they will be implemented to ensure availability of the DGs and retain the ability of both DGFO tanks function being available.

3.2 Human Factors Engineering Considerations

Chapter 18 of the SRP provides guidance to be used by NRC staff while reviewing human factors engineering (HFE) considerations of operating license applications.

3.2.1 Review of Changes to Human Actions

The NRC staff reviewed the licensees proposed TS change to allow for inspection, cleaning, and maintenance of the DGFO storage tank, which is to be incorporated as a condition within the requested change to TS 3.8.3 and constitutes a change to the human actions relied upon to restore system operability during a beyond-design-basis event within the facility licensing basis.

Specifically, the initial conditions for this trained operator action will be changed from the usual conditions.

Chapter 18 of the SRP indicates that, for requests associated with changes to important human actions, applicable acceptance criteria are contained in NUREG -1764. NUREG-1764 provides guidance for determining the level of HFE review required for such requests, and the HFE criteria to be considered while completing the NRC staffs evaluation.

The following sections discuss the NRC s taffs review of the licensees LAR, as supplemented, in accordance with the guidance in NUREG-1764.

3.2.2 Determination of the Human Factors Engineering Review Level

The NRC staff noted that the licensees LAR was not a risk-informed submittal and, consistent with that, considered the guidance in s ection 2.4 of NUREG-1764, Screening Process for Non-Risk-Informed Change Requests.

The NRC staff determined that the human actions being considered are similar to the actions involving risk significant systems, listed in t able A.1, Generic BWR [Boiling-Water Reactor]

Human Actions That are Risk-Important, in NUREG-1764. Subsequently, to determine whether the proposed change to human actions warranted an initially -estimated assignment of a Level II or a Level III review, the NRC staff considered the following:

• The DGFO storage tank being removed from service for cleaning and inspection would require the following analogous operator monitoring/actions for the installed temporary fuel oil storage tanks and the required emergency diesel generator ( EDG) day tank.

These actions will be described in procedures or temporary modification documents utilized during the inspection evolution. These procedures or temporary modification documents are compensatory measures as described in the s ection 3.4, Defense-in -

Depth Contingency Measures, of attachment 1 to the LAR:

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o Both qualified offsite power sources are planned to remain operable during the tank cleaning evolution which is one more offsite source than required by TS 3.8.2.

o A mobile fuel tanker with approximately 7000 gallons of fuel is maintained on the [Cooper] Owner Controlled Area as a holding tank for fuel deliveries. This tanker has the capability to supply fuel to the in-service permanent storage tank and supports greater than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of full load operation for one DG.

Work instructions for off-loading the mobile tanker into the permanent storage tanks exist in an approved procedure. Additionally, work instructions exist in an approved procedure to off-load the mobile tanker directly into the DG day tank when the fuel transfer system is unavailable concurrent with a loss of offsite power. This fuel tanker is considered available as an additional defense in depth fuel source for the DGs.

o The permanent DGFO storage tanks and the temporary DGFO storage tanks associated with the tank cleaning and inspection activities are located in the southeast corner of the [protected area (PA)]. The mobile fuel tanker, which is currently maintained on site to support refilling of the DGFO storage tanks is located outside the southwest corner of the PA. This provides a diversity of locations for fuel supporting a minimum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of full load DG operation.

o Replenishment of fuel oil from offsite, if necessary, can be accomplished in approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> using existing fuel oil suppliers.

o The manual actions required to ensure a 7-day supply of fuel oil are performed outside the reactor building. The additional defense-in -depth strategies ensure that fuel oil will be supplied to the DGs for the required 7 days.

o [Cooper] has a Supplemental Diesel Generator (SDG) that provides another level of defense-in-depth. The SDG is rated at 3250 [ kilowatts ], 4160 volts, and can be connected to one of the two essential busses within 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />. The SDG is available as a defense-in -depth alternate source of [ alternating current] power to one emergency bus to mitigate a station blackout event during a loss of offsite power. The SDG has its own separate fuel system and can carry the selected loads for a minimum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> without r efueling.

• While draining the DGFO storage tanks is a potentially risk-important human action, based on the following considerations, the NRC staff concluded that this review warranted an assignment of a Level III review for the licensees submittal based on the following considerations:

o The evolution is occurring during refueling when the reactor vessel cavity is flooded.

o The temporary fuel oil storage tank will be supplying fuel oil to the remaining in-service EDG.

o The defense-in -depth of the unit, along with the overall low risk significance of the licensees requested TS change.

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3.2.2 Qualitative Assessment of Human Action Safety -Significance

In accordance with s ection 2.3.5.1 of NUREG-1764, the NRC staff determined that the licensees submittal warranted a qualitative assessment of (1) personnel functions and tasks and (2) design support for task performance. In conducting this assessment, the staff considered the following factors:

• Change in Tasks: Has the requested change significantly modified the way in which personnel perform their tasks?

• Change in Performance Context: Has the requested change created, in some way, a new context for task performance?

• Change in Procedures: Has the requested change significantly changed the procedures that personnel use to perform the task?

• Change in Training: Has the requested change significantly modified the training, or is the task not addressed in training?

3.2.3 Task and Performance Context Considerations

Regarding task and performance considerations, the NRC staff determined that the use of the temporary tanks does not constitute a significant change of the task. The task requirements are the same as those for the DGFO storage tank, just being performed with the temporary tanks.

There is a manual action to route a discharge hose from a portable fuel oil transfer pump, which takes suction on the temporary tanks, or the out-of-service tank, to transfer the fuel oil to the required in-service permanent DGFO storage tank. As noted in section 3.9 of the LAR, a timing analysis for transferring fuel oil from the temporary tanks to the in-service permanent DGFO storage tank using the planned special procedures and temporary equipment staging resulted in the following timeline:

• Two operators and vendor personnel report to the temporary tanks where the portable fuel oil transfer pump and transfer hoses are locatedapproximately 5 minutes. During a refuel outage, additional operators are available to assist the operating crew.

• The operators work with vendor personnel to route the transfer hoses from the transfer pump to the in-service permanent DGFO storage tank connection approximately 30 minutes.

• In parallel, one operator proceeds to the required DG room to monitor permanent DGFO storage tank level while the second operator prepares to operate or direct operation of the portable fuel oil transfer pumpapproximately 10 minutes.

• The portable fuel oil transfer pump is started, and filling commences approximately 5 minutes.

• Therefore, approximately 50 minutes will be needed to commence filling the in -

service permanent DGFO storage tank.

3.2.4 Procedure and Training Considerations

The NRC staff considered the significance of any changes to procedures or training associated with this TS change, and whether these procedures would serve to ensure that operators were aware of the change. In section 3.9, Human Factors Evaluation, of attachment 1 to the LAR, the licensee states that special procedures will be in place and Section 3.2, Temporary Fuel Oil Supply Configuration states that training, walkthroughs and briefings will be provided to the operators for the fuel oil resupply activities to the required EDG s day tank during the DGFO storage tank inspection.

3.2.5 Human Factors Conclusion

The NRC staff reviewed the proposed changes and considered the actions involved with the DGFO storage tank inspection activities and the proposed inspection occurs during the refueling of the reactor. Also, the staff found that plant operation in compliance with existing regulations did not present any issues of unique or specific significance to suggest that such compliance (i) may not produce the intended or expected level of safety or (ii) may present an undue risk to public safety. The staff reviewed table A.1, in appendix A of NUREG -1764 and verified that no actions from that table are included in the LAR.

The NRC staff concluded that while draining the DGFO storage tanks is a potentially risk -

important human action, this evolution is occurring during refueling when the reactor vessel cavity is flooded and the in-service DGFO storage tank and temporary tanks will be supplying fuel oil to the EDG, thus, defense-in-depth will be maintained, and the risk significance remains low. In addition, any actions that are new or impacted by this temporary modification will be proceduralized and operators will receive training.

Based on the review of table A.2, in NUREG-1764 and range in which the operator actions fall according to NUREG-1764, a Level III review, the least stringent, human factors review was determined to be appropriate. The NRC staff found that the defense-in -de pth actions are unchanged from the current licensing basis, and the evolution occurs during an outage when the vessel is flooded. Therefore, the staff concluded that there is no significant degradation in safety as a result of approving this amendment with regards to human factors engineering.

3.3 Physical Security Evaluation

In the LAR, the licensee did not propose changes to the site security plan. The Cooper Security Plan includes the Physical Security Plan, Training and Qualification Plan, the Safeguards Contingency Plan (hereafter, Security Plan) 1, and the Cyber Security Plan 2.

1 The Cooper Security Plan contains Safeguards Information (SGI) and is withheld from public disclosure in accordance with 10 CFR 73.21, Protection of Safeguards Information: Performance requirements, and 10 CFR 73.22, Protection of Safeguards Information: Specific Requirements. Those persons with the correct access authorization and need-to -know may view the Cooper Security Plan, which is in the Secure Agency-Wide Database for SGI.

2 The Cooper Cyber Security Plan was not part of this review.

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In section 3.8, Safety/Security Evaluation, of attachment 1 to the LAR, the licensee states, in part:

10 CFR 73.58 requires licensees to assess and manage the potential adverse effects on safety and security, including the site emergency plan, before implementing changes to plant configurations, facilities conditions, or security.

CNS Procedure 0-SEC -INTERFACE was used to assess the impact of this maintenance activity on safety and security.

The project to clean and inspect the DGFO Storage tanks, including all equipment laydown areas will be located within the PA [protected area]

boundary. The two temporary tanks and associated equipment will be located an estimated distance of 21 feet from the adjacent buildings to provide sufficient standoff distances. The determined standoff distance for all structures using the guidance of NFPA [National Fire Protection Association] 30-2015 is five feet. The five-foot minimum standoff distance will also be applied to the adjacent bullet resistant enclosures (BRE), as current staging locations are approximately fifteen feet from the BREs. Each temporary tank is also a double-walled carbon steel tank. Both tanks and the associated equipment will be placed in a berm system to contain fuel in the event that a leak does occur. CNS' work document includes steps to notify security prior to staging equipment inside the PA and in the potential event of a fuel leak or fire in order to evaluate the condition.

Each of the two tanks and the associated equipment will be arranged to best support the project but also to minimize impact on both the field of fire and normal security operations. The proposed locations of the temporary tanks and the associated equipment will be located within the PA boundary in a manner to not affect normal security operations. At the identified locations, no disruption to field of fire and no impacts to intrusion detection monitoring capability will occur.

Security conducted a walkdown with Engineering and verified that the laydown will not change or decrease the effectiveness of the NRC approved Security Plan. It will not invalidate the security protective strategy (e.g., communications, response timelines and pathways), equipment and systems (particularly target sets), or protected fighting positions and fields of fire. Current laydown of the tanks and equipment will not impact interior and exterior sensors, zone of detection and field of view, alarm communications, or access control systems or assessment functions. Laydown of the tanks and equipment will not impact the PA or Isolation Zone from a hardened security defensive position or obstruct security.

In summary, placing the subject temporary tanks beyond the NFPA 30-2015 recommended standoff distance of five feet provides assurance the temporary tanks and equipment do not create a substantial increase in risk to Security structures or protective strategies. The staging of the tanks and equipment will not disrupt field of view for BREs and there will be no impact to intrusion detection monitoring capability, vital areas, target sets and security protective strategy.

For this review, the NRC staffs evaluation of the LAR considered the planned temporary plant changes and the extent that these changes may impact the site security plans, protective strategy, and their implementation. The NRC staff did not identify any impact to site security positions in its review of the licensee provided drawings depicting the general location for the temporary storage tanks, equipment laydown area, and configuration during fuel transfer. While interlocking/overlapping fields of fire could not be verified by NRC staff through evaluation of the drawings, the licensee stated that site security staffconducted a walkdown with site e ngineering staff and verified the temporary plant changes will not invalidate the sites protective strategy (e.g., communications, response timelines and pathways), equipment and systems (particularly target sets), or protected fighting positions and fields of fire. Based on the licensees safety/security interface described in the LAR, the NRC staff determined there will be no impact to the licensees NRC-approved security plans during this temporary configuration.

Based on the licensees statements provided in the LAR and NRC staffs review of the NRC-approved Cooper security plans, NRC staff have determined that the temporary configuration will not change or decrease the effectiveness of the sites protective strategy. Therefore, as discussed above in this safety evaluation, the proposed changes will allow the licensee to continue to meet the applicable requirements in 10 CFR 73.55 and 10 CFR 73.58.

3.4 NRC Staff Determination

The licensee described the operator actions associated with the one-time changes to the TS to support the periodic cleaning and examination under the License Renewal Buried Piping and Tanks Inspection Program of the DGFO s torage tank. The staff reviewed the list of proposed scheduled activities and verified that these actions are in the low -risk category by assessing them against the applicable tables in NUREG-1764.

The NRC staff confirmed that operator actions planned as part of this amendment do not provide any significant increase in risk to the facility and change to operator actions because new compensatory measures contained in the current licensing basis continue to provide a reasonable means of defense-in -depth during the outage period. Therefore, the staff finds the requested change to TS 3.8.3 acceptable.

The NRC staff reviewed the actions included in the proposed changes to the TS using NUREG-1764. The staff confirmed that the operator actions described in the amendment are low-risk, and therefore the staff conducted a Level III review, which focused on ensuring that defense-in -depth is not degraded. The staff found that the defense-in -depth actions are unchanged from the current licensing basis and therefore the staff concluded that there is no significant degradation in safety with this amendment in regard to human factors engineering.

In conclusion, the NRC staff finds TS changes acceptable for the proposed amendment to extend the expiration on a one-time basis for the DGFO storage tanks to be individually inoperable for up to 14 days for the purpose of performing required inspection, cleaning, and any necessary repair activities. Additionally, the staff concludes that the temporary DGFO configuration along with the proposed compensatory measures provide reasonable assurance that Cooper has the capability to maintain a safe shutdown condition during the Mode 4 and 5 inspection and maintenance activities. Accordingly, the NRC staff concludes that the proposed change will not impact the licensee's continuous compliance with the regulatory requirements in 10 CFR 50.36(c)(2)(i), and the guidance in NUREG-1764 were met and, therefore, the proposed changes are acceptable.

4.0 State Consultation

In accordance with the Commissions regulations, the Nebraska State official was notified of the proposed issuance of the amendment on May 10, 2024. 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 28, 2023 (88 FR 83168), 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 Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributors: G. Curran, NRR K. West, NRR M. Keefe-Forsyth, NRR T. Leach, NSIR

Date: July 3, 2024

ML24134A178 *concurrence via email NRR-058 OFFICE NRR/DORL/LPL4/PM* NRR/DORL/LPL4/LA* NRR/DSS/STSB/BC* NRR/DSS/SCPB/BC*

NAME TByrd PBlechman SMehta MValentin DATE 5/13/2024 5/14/2024 5/31/2024 5/31/2024 OFFICE NRR/DRO/IOLB/BC* NRR/DEX/EMIB/BC* NRR/DRO/IRAB/BC* NSIR/DPCP/RSB/BC*

NAME LNist SBailey PFinney AMarshall DATE 5/16/2024 5/31/2024 5/15/2024 5/15/2024 OFFICE OGC - NLO* NRR/DORL/LPL4/BC* NRR/DORL/LPL4/PM*

NAME IMurphy JRankin TByrd DATE 6/26/2024 7/3/2024 7/3/2024