NLS2024024, Emergency License Amendment Request to Revise Technical Specifications 3.3.1.1, Reactor Protection (RPS) Instrumentation

Emergency License Amendment Request to Revise Technical Specifications 3.3.1.1, Reactor Protection (RPS) Instrumentation

ML24092A376
Person / Time
Site:	Cooper
Issue date:	04/01/2024
From:	Dia K Nebraska Public Power District (NPPD)
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
NLS2024024
Download: ML24092A376 (1)

Text

NLS2024024 April 1, 2024 H

Nebraska Public Power District "Always there when you need us" 50.90 50.91(a)(5)

Attention: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001

Reference:

Emergency License Amendment Request to Revise Technical Specifications 3.3.1.1, "Reactor Protection (RPS) Instrumentation" Cooper Nuclear Station, Docket No. 50-298, Renewed License No. DPR-46 Letter from Khalil Dia, Nebraska Public Power District, to the U.S. Nuclear Regulatory Commission, dated March 31, 2024, "Request for Notice of Enforcement Discretion for Technical Specifications 3.3.1.1, "Reactor Protection (RPS) Instrumentation"

Dear Sir or Madam:

Pursuant to IO CPR 50.90, "Application for amendment oflicense, construction permit, or early site permit," Nebraska Public Power District (NPPD) is submitting a request for an amendment to Renewed Facility Operating License No. DPR-46 for Cooper Nuclear Station (CNS). The proposed amendment is being requested on an emergency basis pursuant to 10 CPR 50.9l(a)(5) and is a follow up to the notice of enforcement discretion in the Reference.

At 1437, Central Daylight Time, on March 29, 2024, CNS entered Technical Specifications (TS) 3.3.1.1, Conditions A and B for Function 8, as a result of a concern bringing into question the channel independence associated with both sets of Turbine Stop Valve RPS position switches, which is original station design. The proposed change is necessary to allow development of a resolution to this design question without requiring a reduction in Reactor Thermal Power below 29.5% without a commensurate benefit in nuclear safety. In the Reference, NPPD requested approval for enforcement discretion from TS 3.3.1.1 Conditions A and B, in accordance with Nuclear Regulatory Commission (NRC) Enforcement Manual, Appendix F, "Notices of Enforcement Discretion." On March 29, 2024, the NRC granted verbal approval of NPPD's enforcement discretion request.

The proposed amendment adds a temporary footnote to TS Table 3.3.1.1-1, "Reactor Protection System Instrumentation," that is applicable to Function 8, Turbine Stop Valve - Closure. The current design configuration of the Turbine Stop Valve position switches that input to the RPS does not meet channel independence criteria. The temporary footnote allows NPPD to not enter TS 3.3.1.1, Condition A or B for the channel independence condition.

COOPER NUCLEAR STATION 72676 648A Ave/ P.O. Box 98 / Brownville, NE 68321 http://www.nppd.com

NLS2024024 Page 2 of 3 provides a description and assessment of the proposed change. Attachment 2 contains a list of commitments. Attachment 3 provides the existing TS pages marked up to show the proposed change. Attachment 4 provides revised (clean) TS pages. Attachment 5 contains a markup of the TS Bases for information only.

Approval of the proposed amendment is requested by April 5, 2024. This is a one-time request that will remain in effect until startup from RE33 in the fall of 2024.

NPPD has determined that there are no significant hazards considerations associated with the proposed change and that the TS change qualifies for a categorical exclusion from environmental review pursuant to the provisions of 10 CFR 51.22( c )(9).

The proposed TS change has been reviewed by the necessary safety review committees (Station Operations Review Committee and Safety Review and Audit Board). Amendments to the CNS Renewed Operating License through Amendment 274 issued on January 3, 2024, have been incorporated into this request. In accordance with 10 CFR 50.91, "Notice for public comment; State consultation," a copy of this application, with attachments, is being provided to the designated State of Nebraska Official. Copies to the NRC Region IV office and the CNS Resident Inspectors are also being provided in accordance with 10 CFR 50.4(b )(1 ).

There are regulatory commitments made in this submittal. See Attachment 2. If you should have any questions regarding this submittal, please contact Linda Dewhirst, Regulatory Affairs and Compliance Manager, at (402) 825-5416.

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

Executed On: ~

l I / 2--o Lt{

Date Site Vice President

/dv Attachments: 1. Description and Assessment

2. List of Commitments

3. Proposed Technical Specifications Change (Mark-up)

4. Revised Technical Specifications Page

5. Technical Specifications Bases Pages - Information Only cc:

Regional Administrator w/ attachments USNRC - Region IV

NLS2024024 Page 3 of 3 Cooper Project Manager w/ attachments USNRC - NRR Plant Licensing Branch IV Senior Resident Inspector w/ attachments USNRC-CNS Nebraska Health and Human Services w/ attachments Department of Regulation and Li censure NPG Distribution w/ attachments CNS Records w/ attachments

NLS2024024 Page 1 of 8 Description and Assessment Cooper Nuclear Station, Docket No. 50-298, Renewed License No. DPR-46 1.0 Summary Description 2.0 Detailed Description 2.1 Current Technical Specifications Requirements 2.2 Reason for the Proposed Change 2.3 Description of the Proposed Change 3.0 Technical Evaluation 3.1 System Design and Operation 3.2 Technical Evaluation 3.3 Safety Assessment 3.4 Compensatory Measures (Attachment 2) 3.5 Planned Actions 3.6 Conclusion 4.0 Regulatory Analysis 4.1 Applicable Regulatory Requirements/Criteria 4.2 Precedent 4.3 No Significant Hazards Consideration Determination Analysis 4.4 Conclusion 5.0 Environmental Evaluation

NLS2024024 Page 2 of 8 1.0

SUMMARY

DESCRIPTION In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Nebraska Public Power District (NPPD) is submitting a request for an amendment to Renewed Facility Operating License (OL) No. DPR-46 for Cooper Nuclear Station (CNS). The proposed change would amend the OL by adding a temporary footnote to Technical Specifications (TS) Table 3.3.1.1-1, "Reactor Protection System Instrumentation," that is applicable to the Turbine Stop Valve - Closure function (Function 8). The current design configuration of the Turbine Stop Valve (TSV) position switches that input to the Reactor Protection System (RPS) does not meet channel independence criteria. The temporary footnote allows NPPD to not enter TS 3.3.1.1, Condition A and B until the channel independence condition is resolved no later than startup from Refuel Outage 33.

2.0 DETAILED DESCRIPTION 2.1 Current Technical Specifications Requirements CNS TS 3.3.1.1, Table 3.3.1.1-1, Function 8 for the Turbine Stop Valve - Closure requires two channels per trip system. With one or more required channels inoperable, Condition A is entered with a required action to trip the channel or associated trip system within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. With one or more functions with one or more required channels inoperable in both trip systems, Condition B is entered with a required action to place one channel in one trip system in trip or place one trip system in trip within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. If Condition A or B Completion Times are not met, then Condition E is entered which requires thermal power to be reduced to <29.5% rated thermal power within four hours.

2.2 Reason for the Proposed Change A concern has been raised with how the RPS function for the TSV position switches meet channel independence criteria in its current design configuration. The two position switches on each TSV are mechanically connected to actuate together on TSV closure. TS 3.3.1.1, Table 3.3.1.1-1, Function 8, requires two channels per trip system. The configuration of the mechanical trip input to the TSV position switches does not meet channel independence criteria.

This configuration is unique to the TSVs.

2.3 Description of the Proposed Change The proposed change adds a temporary Note (d) to TS 3.3.1.1, Table 3.3.1.1-1 that would apply to Function 8, Turbine Stop Valve - Closure. This temporary footnote would allow NPPD to not enter Conditions A and B for the channel independence issue until it is resolved, but no later than startup from CNS' RE33. A modification is potentially needed and would not be able to be implemented until RE33 in the Fall of 2024. provides the existing CNS TS page marked to show the proposed change. provides the existing CNS TS page retyped to show the proposed change. contains a markup of the CNS TS bases for information only.

NLS2024024 Page 3 of 8

3.0 TECHNICAL EVALUATION

3.1 System Design and Operation The RPS, as described in the Updated Safety Analysis Report, Section VII-2, includes sensors, relays, bypass circuits, and switches that are necessary to cause initiation of a reactor scram.

Functional diversity is provided by monitoring a wide range of dependent and independent parameters. The input parameters to the scram logic are from instrumentation that monitors reactor vessel water level, reactor vessel pressure, neutron flux, main steam line isolation valve position, turbine control valve fast closure, trip oil pressure, TSV position, drywell pressure, and scram discharge volume water level, as well as reactor mode switch in shutdown position and manual scram signals. There are at least four redundant sensor input signals from each of these parameters (with the exception of the manual scram signal and the reactor mode switch in shutdown scram signal).

Turbine Stop Valve - Closure signals are initiated from position switches located on each of the two TSV s. Two independent position switches are associated with each stop valve. A linkage on each TSV transmits valve movement to contact the position switch arm for the upper position switch. The upper position switch arm is attached by another linkage to the lower position switch arm. This arrangement ensures simultaneous rotation of both position switches' splined shafts. Both of the switches from one TSV provide input to RPS trip system A; the two switches from the other TSV provide input to RPS trip system B. Thus, each RPS trip system receives two Turbine Stop Valve - Closure channel inputs from a TSV, each consisting of one position switch assembly with two contacts, each inputting to a relay.

The Turbine Stop Valve - Closure Allowable Value is selected to detect imminent TSV closure, thereby reducing the severity of the subsequent pressure transient.

Four channels of Turbine Stop Valve - Closure Function, with two channels in each trip system, are required to be operable to ensure that no single instrument failure will preclude a scram from this Function if both TS Vs should close.

3.2 Technical Evaluation No current degraded equipment conditions have been identified and the configuration does not result in any increase in likelihood of degradation. The configuration of the RPS position switches for TSV closure does not prevent the RPS from performing its specified safety function.

There is no indication that this design configuration has been changed since initial plant startup and original licensing.

A failure of the linkage between the position switch arms, such that the upper and lower position switch arms become disconnected from each other would only prevent the lower position switch from actuating on TSV closure, with the RPS function still accomplished.

The design of the RPS position switches on the TSV is such that internal mechanical binding of the switch mechanism does not prevent rotation of the splined shaft. This is due to the spring-

NLS2024024 Page 4 of 8 loaded floating arm between the cam follower and the switch contact block. Therefore, internal mechanical binding of one position switch will not prevent rotation of the splined shaft of either position switch, allowing the RPS function to be accomplished. However, within the linkage configuration there is a potential failure that could prevent actuation of both switches. If a failure occurred that prevents rotation of the upper position switch about the fulcrum ( splined shaft) this could prevent actuation of both switches. Over the course of the plant's operating history, the station has not experienced this failure; the freedom of movement and proper rotation are verified by periodic surveillance of the switches.

TSV #1 position switch replacement and calibration in January 2024 and successful examination and actuation of the position switches in March 2024 supports that the TSV #I linkages and position switches will operate as required to support the RPS function. TSV #2 successful RPS relay actuation on valve closure during an RE32 surveillance, followed by successful examination and actuation of the position switches and linkages every 13 weeks, supports that the TSV #2 switches will operate as required to support the RPS function.

3.3 Safety Assessment Scrams based on turbine governor valve fast closure and TSV fast closure signals are anticipatory in nature in order to provide additional margin to overpressurization of the reactor coolant system boundary. The high reactor vessel pressure scram in conjunction with the pressure relief system is sufficient to maintain reactor coolant boundary pressure below applicable limits.

The reactor coolant boundary analysis is based on the Main Stearn Isolation Valve closure event with flux scram. This event does not assume TSV or control valve fast closure scrams. Pressure values are below applicable limits when evaluating the shortest closure time of three seconds.

The TSVs close via depressurization of the stop valve emergency trip header. Depressurization of this header will also depressurize the governor ( control) valve emergency trip header. This results in a separate scram signal [TS Table 3.3.1.1-1]. This scram signal is the basis for the turbine control valve fast closure (generator load rejection event), which is explicitly analyzed.

Fuel damage is avoided by setting the most limiting operating Minimum Critical Power Ratio analyzed for the cycle. Inadvertent HPCI event sets the most limiting operating Minimum Critical Power Ratio from the date of the LAR to the end of Cycle 33. Turbine trip without bypass (initiated by turbine stop valve closure) is not limiting for the remainder of Cycle 33.

3.4 Compensatory Measures (Attachment 2)

In order to minimize main turbine trip risk, the station will utilize the protected equipment program in order to drive heightened sensitivity and risk management actions associated with equipment with elevated potential for initiating a main turbine trip. In addition, this process will drive management review and approval for activities on or near this equipment.

NLS2024024 Page 5 of 8 The Critical Evolution Meeting process will be applied to Procedure 6.RPS.302, "Main Turbine Stop Valve Closure and Steam Valve Functional Test," to ensure additional management oversight and approval are applied to activities that exercise the main TSV position switches.

3.5 Planned Actions For long-term corrective actions to restore compliance with TS 3.3.1.1, all options will be evaluated, including a potential design change/system modification or license amendment request. The process for a design change requires a failure modes and effects analysis be conducted to ensure that all failure modes are identified and addressed. Inherent to this review, a practicable design change may result in a new failure mode that renders the system less reliable, if implemented. Therefore, it is prudent to evaluate all options to address the condition.

3.6 Conclusion.

The RPS function for the TSV position switches does not meet channel independence criterion.

There is no known current degradation with the TSV position switches.

The function of other redundant trips or diverse methods of reactor shutdown ( e.g., other automatic RPS trips, alternate rod insertion, or manual reactor trip capacity) remain unaffected by this concern. Therefore, there is no other equipment impacts that may have risk significance, increase the probability of a plant transient, or may complicate the recovery from a transient.

Assuming the TSV position switches are not operable and a scram signal from the TSV position does not occur, existing plant safety analysis demonstrates that this condition would be mitigated by other RPS trip functions.

4.0 REGULATORY ANALYSIS

4.1 Applicable Regulatory Requirements/Criteria CNS was not licensed to the 10 CFR 50, Appendix A, General Design Criteria (GDC). CNS was designed and constructed to meet the principle design criteria described in the Atomic Energy Commission's (AEC) proposed rule, "General Design Criteria for Nuclear Power Plant Construction Permits," published in the Federal Register on July 11, 1967 (32 FR 10213). The degree of conformance to the 1967 proposed GDC is described in Appendix F, "Conformance to AEC Proposed General Design Criteria" to the Updated Safety Analysis Report for CNS. The following Nuclear Regulatory Commission requirements were evaluated for their applicability to the proposed change. Criterion 20 is the subject of this emergency license amendment request for not having channel independence for the TSV position switches.

Criterion 14 - Core Protection Systems Core protection systems, together with associated equipment, shall be designed to act automatically to prevent or to suppress conditions that could result in exceeding acceptable fuel damage limits.

NLS2024024 Page 6 of 8 The reactor protection system, described in Section VII-2 in association with other safety systems, automatically senses and limits conditions which could lead to unacceptable fuel damage. This system acts independently of, and overrides, other controls over control rod movement to initiate the necessary protective action. Evaluation of the protective action is given in the safety analysis.

Criterion 20 - Protection Systems Redundancy and Independence Redundancy and independence designed into protection systems shall be sufficient to assure that no single failure or removal from service of any component or channel of a system will result in loss of the protection function. The redundancy provided shall include, as a minimum, two channels of protection for each protection function to be served. Different principles shall be used where necessary to achieve true independence of redundant instrumentation components.

Protection system design includes the capability of providing the required protection, even with a component or channel inoperative due to failure or removal. Each of the protection function actions are initiated by a variety of sensed station conditions and by at least two instrument channels. This protection action is not dependent on a single channel.

4.2 Precedent None.

4.3 No Significant Hazards Consideration Determination Analysis Nebraska Public Power District (NPPD) is requesting to amend the Renewed Facility Operating License (OL) No. DPR-46 for Cooper Nuclear Station. The proposed change would amend the OL by adding a temporary footnote to the Technical Specifications, Section 3.3.1.1, "Reactor Protection System Instrumentation," Table 3.3.1.1-1, Function 8, "Turbine Stop Valve - Closure" as follows:

"The Turbine Stop Valve - Closure function does not meet channel independence criteria.

Condition A and B are not required to be entered for this condition. This temporary footnote is applicable through Cycle 33 until startup from RE33."

NPPD has evaluated whether or not a significant hazards consideration is involved with the proposed amendment by fpcusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:

1)

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

Response: No

NLS2024024 Page 7 of 8 The proposed amendment is to allow operation of Cooper Nuclear Station for the remainder of Cycle 33 with the Reactor Protection System (RPS) function for the Turbine Stop Valve (TSV) - Closure not meeting channel independence criteria. The TSV position switches that initiate the RPS function for the TSV closure are not accident initiators. The RPS functions to prevent fuel damage, limit system pressure and thus restrict the release of radioactive material.

Scrams based on turbine governor valve fast closure and TSV fast closure signals are anticipatory in nature in order to provide additional margin to overpressurization of the reactor coolant system boundary. The high reactor vessel pressure scram in conjunction with the pressure relief system is sufficient to maintain reactor coolant boundary pressure below applicable limits. The reactor coolant boundary analysis is based on the Main Steam Isolation Valve closure event with flux scram. This event does not assume TSV or control valve fast closure scrams.

Fuel damage is avoided by setting the most limiting operating Minimum Critical Power Ratio based on the most limiting event analyzed for the cycle. The limiting pressurization events from the cycle reload analysis are inadvertent injection of High Pressure Coolant Injection, generator load rejection without bypass, and feedwater controller failure (maximum demand). Since the Turbine Stop Valve - Closure function is not limiting for the cycle, the consequences of an accident are not increased.

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

2)

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

Response: No The proposed amendment is to allow operation of Cooper Nuclear Station for the remainder of Cycle 33 with the RPS function for the Turbine Stop Valve - Closure not meeting channel independence criteria. This amendment does not change the design function or operation of the RPS instrumentation. No changes in processes are being proposed that would affect the operation of the RPS instrumentation or affect its ability to perform its design function.

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

3)

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

Response: No The proposed amendment is to allow operation of Cooper Nuclear Station for the remainder of Cycle 33 with the RPS function for the Turbine Stop Valve - Closure not meeting channel independence criteria. Margin of safety is related to the confidence in the ability of the

NLS2024024 Page 8 of 8 fission product barriers to perform their design functions during and following an accident.

These barriers include the fuel cladding, the Reactor Coolant System, and the containment system. Notwithstanding that Criterion 20, "Protection Systems Redundancy and Independence," of the 1967 proposed General Design Criteria is not fully met, the proposed amendment will not challenge the acceptability of any analytical limits under normal, transient, and accident conditions. All applicable design and safety limits will continue to remain satisfied such that the fission product barriers will continue to perform their design functions.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above, NPPD concludes that the proposed amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.

4.4 Conclusion In conclusion, based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

5.0 ENVIRONMENTAL EVALUATION NPPD has determined that the proposed amendment would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement. However, the proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure.

Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22( c )(9). Therefore, pursuant to 10 CFR 51.22(b ), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

NLS2024024 Page 1 of 1 List of Commitments Cooper Nuclear Station, Docket No. 50-298, Renewed License No. DPR-46 TYPE (check one)

ONE-CONTINUING SCHEDULED TIME COMPLETION COMMITMENT/COMMITMENT NO.

ACTION COMPLIANCE DATE NLS2024024-01 In order to minimize main turbine trip risk, the station will utilize the protected equipment program in order to drive heightened sensitivity and risk management actions associated with X

4/5/24 equipment with elevated potential for initiating a main turbine trip. In addition, this process will drive management review and approval for activities on or near this equipment.

NLS2024024-02 The Critical Evolution Meeting process will be applied to Procedure 6.RPS.302, "Main Turbine Stop Valve Closure and Steam Valve Functional X

4/5/24 Test," to ensure additional management oversight and approval are applied to activities that exercise the main turbine stop valve position switches.

NLS2024024 Page 1 of2 Proposed Technical Specifications Change (Mark-up)

Cooper Nuclear Station, Docket No. 50-298, Renewed License No. DPR-46 Revised Page 3.3-8

FUNCTION

7.

Scram Discharge Volume Water Level - High

a.

Level Transmitter

b.

Level Switch

8.

Turbine Stop Valve - Closure

9.

Turbine Control Valve Fast Closure, DEH Trip Oil Pressure -

Low

10. Reactor Mode Switch -

Shutdown Position

11. Manual Scram RPS Instrumentation 3.3.1.1 Table 3.3.1.1-1 (page 3 of 3)

Reactor Protection System Instrumentation APPLICABLE MODES OR OTHER SPECIFIED CONDITIONS 1,2 1,2

29.5% RTP

29.5% RTP 1,2 1,2 REQUIRED CHANNELS PER TRIP SYSTEM 2

2 2

2 2

CONDITIONS REFERENCED FROM REQUIRED SURVEILLANCE ALLOWABLE ACTION D.1 REQUIREMENTS VALUE G

SR 3.3.1.1.4 s 90 inches SR 3.3.1.1.9 H

G H

E E

G H

G H

SR 3.3.1.1.12(a,b)

SR 3.3.1.1.13 SR 3.3.1.1.15 SR 3.3.1.1.4 SR 3.3.1.1.9 SR 3.3.1.1.12 SR 3.3.1.1.13 SR 3.3.1.1.15 SR 3.3.1.1.4 SR 3.3.1.1.9 SR 3.3.1.1.12 SR 3.3.1.1.13 SR 3.3.1.1.15 SR 3.3.1.1.4 SR 3.3.1.1.9 SR 3.3.1.1.12 SR 3.3.1.1.13 SR 3.3.1.1.15 s 90 inches s 90 inches s 90 inches SR 3.3.1.1.4 s 10% closed SR 3.3.1.1.9 SR 3.3.1.1.12 SR 3.3.1.1.13 SR 3.3.1.1.14 SR 3.3.1.1.15 SR 3.3.1.1.4

1018 psig SR 3.3.1.1.9 SR 3.3.1.1.12(a,b)

SR 3.3.1.1.13 SR 3.3.1.1.14 SR 3.3.1.1.15 SR 3.3.1.1.11 SR 3.3.1.1.13 SR 3.3.1.1.11 SR 3.3.1.1.13 SR 3.3.1.1.9 SR 3.3.1.1.13 SR 3.3.1.1.9 SR 3.3.1.1.13 NA NA NA NA (a) If the as-found channel setpoint is outside its predefined as-found tolerance, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service.

(b) The instrument channel setpoint shall be reset to a value that is within the as-left tolerance around the Limiting Trip Setpoint (L TSP) at the completion of the surveillance; otherwise, the channel shall be declared inoperable. Setpoints more conservative than the L TSP are acceptable provided that the as-found and as-left tolerances apply to the actual setpoint implemented in the Surveillance procedures (Nominal Trip Setpoint) to confirm channel performance. The Limiting Trip Setpoint and the methodologies used to determine the as-found and the as-left tolerances are specified in the Technical Requirements Manual.

(c) With any control rod withdrawn from a core cell containing one or more fuel assemblies.

(d) The Turbine Stop Valve - Closure function does not meet channel independence criteria. Condition A and Bare not required to be entered for this condition. This temporary footnote is applicable through Cycle 33 until startup from RE33.

Cooper 3.3-8 Amendment No.

NLS2024024 Page 1 of2 Revised Technical Specifications Page Cooper Nuclear Station, Docket No. 50-298, Renewed License No. DPR-46 Revised Page 3.3.8

FUNCTION

7.

Scram Discharge Volume Water Level - High

a.

Level Transmitter

b.

Level Switch

8.

Turbine Stop Valve - Closure

9. Turbine Control Valve Fast Closure, DEH Trip Oil Pressure -

Low

10. Reactor Mode Switch -

Shutdown Position

11. Manual Scram Table 3.3.1.1-1 (page 3 of 3)

Reactor Protection System Instrumentation APPLICABLE MODES OR OTHER SPECIFIED CONDITIONS 1,2 1,2

.:! 29.5% RTP

.:! 29.5% RTP 1,2 1,2 REQUIRED CHANNELS PER TRIP SYSTEM 2

2 2

2 2

CONDITIONS REFERENCED FROM REQUIRED ACTION D.1 G

H G

H E

E G

H G

H RPS Instrumentation 3.3.1.1 SURVEILLANCE ALLOWABLE REQUIREMENTS VALUE SR 3.3.1.1.4 s 90 inches SR 3.3.1.1.9 SR 3.3.1.1.12(a,b)

SR 3.3.1.1.13 SR 3.3.1.1.15 SR 3.3.1.1.4 SR 3.3.1.1.9 SR 3.3.1.1.12 SR 3.3.1.1.13 SR 3.3.1.1.15 SR 3.3.1.1.4 SR 3.3.1.1.9 SR 3.3.1.1.12 SR 3.3.1.1.13 SR 3.3.1.1.15 SR 3.3.1.1.4 SR 3.3.1.1.9 SR 3.3.1.1.12 SR 3.3.1.1.13 SR 3.3.1.1.15 s 90 inches s 90 inches s 90 inches SR 3.3.1.1.4 s 10% closed SR 3.3.1.1.9 SR 3.3.1.1.12 SR 3.3.1.1.13 SR 3.3.1.1.14 SR 3.3.1.1.15 SR 3.3.1.1.4

.:!1018psig SR 3.3.1.1.9 SR 3.3.1.1.12(a,b)

SR 3.3.1.1.13 SR 3.3.1.1.14 SR 3.3.1.1.15 SR 3.3.1.1.11 SR 3.3.1.1.13 SR 3.3.1.1.11 SR 3.3.1.1.13 SR 3.3.1.1.9 SR 3.3.1.1.13 SR 3.3.1.1.9 SR 3.3.1.1.13 NA NA NA NA (a) If the as-found channel setpoint is outside its predefined as-found tolerance, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service.

(b) The instrument channel setpoint shall be reset to a value that is within the as-left tolerance around the Limiting Trip Setpoint (L TSP) at the completion of the surveillance; otherwise, the channel shall be declared inoperable. Setpoints more conservative than the L TSP are acceptable provided that the as-found and as-left tolerances apply to the actual setpoint implemented in the Surveillance procedures (Nominal Trip Setpoint) to confirm channel performance. The Limiting Trip Setpoint and the methodologies used to determine the as-found and the as-left tolerances are specified in the Technical Requirements Manual.

(c) With any control rod withdrawn from a core cell containing one or more fuel assemblies.

(d) The Turbine Stop Valve - Closure function does not meet channel independence criteria. Condition A and Bare not required to be entered for this condition. This temporary footnote is applicable through Cycle 33 until startup from RE33.

Cooper 3.3-8 Amendment No.

NLS2024024 Page 1 of2 Technical Specifications Bases Pages - Information Only Cooper Nuclear Station, Docket No. 50-298, Renewed License No. DPR-46 Revised Page B 3.3.16

BASES RPS Instrumentation 8 3.3.1.1 APPLICABLE SAFETY ANALYSIS, LCO, and APPLICABILITY (continued)

Cooper channels per trip system for both SDVs, a total of two required channels of each type per trip system, are required to be OPERABLE to ensure that no single instrument failure will preclude a scram from these Functions on a valid signal. These Functions are required in MODES 1 and 2, and in MODE 5 with any control rod withdrawn from a core cell containing one or more fuel assemblies, since these are the MODES and other specified conditions when control rods are withdrawn. At all other times, this Function may be bypassed.

8.

Turbine Stop Valve-Closure A temporary footnote is provided to address that the Turbine Stop Valve -

Closure function does not meet channel independence criteria. This condition involves the mechanical separation of position switches on the TSVs. Until the issue is resolved, Conditions A and Bare not required to be entered because of the channel independence condition. This temporary footnote will be in place until startup from RE33.

Closure of the TSVs results in the loss of a heat sink that produces reactor pressure, neutron flux, and heat flux transients that must be limited. Therefore, a reactor scram is initiated at the start of TSV closure in anticipation of the transients that would result from the closure of these valves. The Turbine Stop Valve-Closure Function is the primary scram signal for the turbine trip and feedwater controller failure maximum demand events analyzed in Reference 3. For this event, the reactor scram reduces the amount of energy required to be absorbed and ensures that the MCPR SL is not exceeded.

Turbine Stop Valve-Closure signals are initiated from position switches located on each of the two TSVs. Two independent position switches are associated with each stop valve. Both of the switches from one TSV provide input to RPS trip system A; the two switches from the other TSV provide input to RPS trip system 8. Thus, each RPS trip system receives two Turbine Stop Valve-Closure channel inputs from a TSV, each consisting of one position switch assembly with two contacts, each inputting to a relay. The relays provide a parallel logic input to an RPS trip logic channel. The logic for the Turbine Stop Valve-Closure Function is such that both TSVs must be closed to produce a scram. Single valve closure will produce a half scram. This Function must be enabled at THERMAL POWER ~ 29.5% RTP as measured by turbine supply pressure. This is accomplished automatically by pressure switches sensing turbine supply pressure; therefore, opening the turbine bypass valves may affect this Function.

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