ML24278A302

Supplement to License Amendment Request to Revise Technical Specifications and Exemption Request from Requirements of 10 CFR 50.62 ATWS Rule to Support the Digital Modernization Project Installation - Rev Unit 2 Technical Spec

ML24278A302
Person / Time
Site:	Limerick
Issue date:	10/04/2024
From:	Para W Constellation Energy Generation
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
Download: ML24278A302 (1)

Text

200 Energy Way Kennett Square, PA 19348 www.constellation.com

10 CFR 50.90

October 4, 2024

U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 ATTN: Document Control Desk

Limerick Generating Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-39 and NPF-85 USNRC Docket Nos. 50-352 and 50-353

Subject:

Supplement to License Amendment Request to Revise Technical Specifications and Exemption Request from Requirements of 10 CFR 50.62 ATWS Rule to Support the Digital Modernization Project Installation - Revise Unit 2 Technical Specification Page

References:

1. Constellation Energy Generation, LLC (CEG) letter to the U.S. Nuclear Regulatory Commission (USNRC), License Amendment Request to Revise the Licensing and Design Basis to Incorporate the Replacement of Existing Safety-Related Analog Control Systems with a Single Digital Plant Protection System (PPS), dated September 26, 2022 (USNRC Agencywide Documents Access and Management System (ADAMS) Accession No. ML22269A569).

2. CEG letter to the US NRC, License Amendment Request to Revise Technical Specifications and Exemption Request from Requirements of 10 CFR 50.62 ATWS Rule to Support the Digital Modernization Project Installation, dated February 17, 2023 (ADAMS Accession No. ML23052A023 ).

3. CEG letter to the US NRC, Supplement to License Amendment Request to Revise the Licensing and Design Basis to Incorporate the Replacement of Existing Safety-Related Analog Control Systems with a Single Digital Plant Protection System (PPS) - Pivot to Unit 1 PPS First Installation in 2026, dated April 23, 2024 (ADAMS Accession No. ML24114A322).

4. CEG letter to the US NRC, Supplement to License Amendment Request to Revise Technical Specifications and Exemption Request from Requirements of 10 CFR 50.62 ATWS Rule to Support the Digital Modernization Project Installation - Revise Unit 2 Technical Specifications, dated May 28, 2024 (ADAMS Accession No. ML24149A211).

In accordance with 10 CFR 50.90, Constellation Energy Generation, LLC (CEG) requested amendments to Renewed Facility Operating License Nos. NPF-39 and NPF-85 for Limerick Generating Station (LGS), Units 1 and 2, respectively (Reference 1). The proposed changes would revise the LGS licensing and design basis to incorporate a planned digital modification at LGS (i.e.,

the LGS Digital Modernization Project).

Supplement to License Amendment Request Docket Nos. 50-352 and 50- 353 October 4, 2024 Page 2

CEG subsequently requested an amendment to Appendix A, Technical Specifications (TS) for LGS, Units 1 and 2, respectively (Reference 2). The proposed changes would revise the LGS TS to adopt features from NUREG-1433, Revision 5, Standard Technical Specifications for General Electric BWR/4 Plants. The proposed changes would support the installation of the new Plant Protection System (PPS) described in Reference 1. Reference 2 also contained an Exemption Request from requirements of 10 CFR 50.62, the Anticipated Transient Without Scram (ATWS) Rule, to support pre-outage installation support activities.

In Reference 3, CEG provided the USNRC an updated PPS installation schedule reflecting LGS, Unit 1 PPS installation in the planned April 2026 refueling outage (Li1R21), and LGS, U nit 2 installation in the planned April 202 7 refueling outage (Li2R19).

In Reference 4, CEG submitted updated proposed TS changes to reflect the LGS, Unit 2 PPS installation in 2027 as communicated in Reference 3. Reference 4, Attachment 1 contained the revised markups of the affected LGS, Unit 2 TS pages. Reference 4, Attachment 2 contained the corresponding LGS, Unit 2 clean TS pages.

The markup and clean TS pages provided in Reference 4 reflected a proposed Insert 2 on TS Page 3/4 3-42. Insert 2 was originally introduced in Reference 2. The change to Insert 2 between the Reference 2 submittal and the Reference 4 submittal was intended to only reflect the change in the implementation schedule as communicated in Reference 3.

Per telephone communications, the USNRC identified and communicated a discrepancy between Insert 2 as provided in R eference 2 and as provided in Reference 4. The discrepancy was also reflected in the provided clean TS page 3/4 3-42 in Reference 4.

of this supplement provides the corrected Insert 2 for TS page 3/4 3-42. Attachment 2 of this supplement provides t he corrected clean TS page 3/4 3-42 which incorporates the corrected Insert 2. The corrections resolve the Insert 2 discrepancy between Reference s 2 and 4.

CEG has reviewed the information supporting a finding of no significant hazards consideration, and the environmental consideration, which was previously provided to the USNRC in the Reference 2 letter. CEG has concluded that the information provided in this supplemental letter does not affect the bases for concluding that the proposed license amendments do not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92. In addition, CEG has concluded that the information in this supplemental letter does not affect the bases for concluding that neither an environmental impact statement nor an environmental assessment needs to be prepared in connection with the proposed amendments.

There are no regulatory commitments contained within this letter.

In accordance with 10 CFR 50.91, Notice for public comment; State consultation, paragraph (b),

CEG is notifying the Commonwealth of Pennsylvania of this license amendment request supplement by transmitting a copy of this letter to the designated State Official.

Supplement to License Amendment Request Docket Nos. 50-352 and 50- 353 October 4, 2024 Page 3

If you have any questions concerning this submittal, please contact Ashley Rickey at 267-533-1427.

I declare under penalty of perjury that the foregoing is true and correct. Executed on this 4 th day of October 2024.

Respectfully,

Wendi Para Sr. Manager - Licensing Constellation Energy Generation, LLC

Attachments:

1. Corrected Insert 2 for Technical Specification P age 3/4 3-42

2. Clean T echnical Specification P age 3/4 3-42

cc: USNRC Region I, Regional Administrator USNRC Project Manager, LGS USNRC Senior Resident Inspector, LGS Director, Bureau of Radiation Protection - Pennsylvania Department of Environmental Protection ATTACHMENT 1

Supplement to License Amendment Request to Revise Technical Specifications and Exemption Request from Requirements of 10CFR50.62 ATWS Rule to Support the Digital Modernization Project Installation - Revise Unit 2 Technical Specification Page

Limerick Generating Station, Unit 2 Renewed Facility Operating License No. NPF-85

Corrected Insert 2 for Technical Specification Page 3/4 3-42 Insert 2

Note: For a period of 30 days preceding exit of OPERATIONAL CONDITION 1 at the start of the 2027 refueling outage, the LCO is not applicable when the following conditions are met:

Maximum Maximum Inoperable Minimum Suppression THERMAL POWER Safety/Relief Valves Pool Water Level

90% RTP 0 of 14 23 feet

87% RTP 0 of 14 22 feet

84% RTP 1 of 14 22 feet

Recirc Runback on Level 3 Function is Available and not in Bypass.

ATTACHMENT 2

Supplement to License Amendment Request to Revise Technical Specifications and Exemption Request from Requirements of 10CFR50.62 ATWS Rule to Support the Digital Modernization Project Installation - Revise Unit 2 Technical Specification Page

Limerick Generating Station, Unit 2 Renewed Facility Operating License No. NPF-85

Clean Technical Specification Page

3/4 3-42 INSTRUMENTATION 3/4.3.4 RECIRCULATION PUMP TRIP ACTUATION INSTRUMENTATION ATWS RECIRCULATION PUMP TRIP SYSTEM INSTRUMENTATION LIMITING CONDITION FOR OPERATION 3.3.4.1 The anticipated transient without scram recirculation pump trip (ATWS-RPT) system instrumentation channels shown in Table 3.3.4.1-1 shall be OPERABLE with their trip setpoints set consistent with values shown in the Trip Setpoint column of Table 3.3.4.1-2.

APPLICABILITY: OPERATIONAL CONDITION 1.

Note: For a period of 30 days preceding exit of OPERATIONAL CONDITION 1 atthe start of the 2027 refueling outage, the LCO is not applicable when the following conditions are met:

THERMAL POWERMaximum Safety/Relief Valves Maximum Inoperable Minimum SuppressionPool Water Level 90% RTP 0 of 14 23 feet 87% RTP 0 of 14 22 feet 84% RTP 1 of 14 22 feet Recirc Runback on Level 3 Function is Available and not in Bypass.

ACTION:

a. With an ATWS recirculation pump trip system instrumentation channeltrip setpoint less conservative than the value shown in the Allowable Values column of Table 3.3.4.1-2, declare the channel inoperable until the channel is restored to OPERABLE status with the channel trip setpoint adjusted consistent with the Trip Setpoint value.

b. With the number of OPERABLE channels one less than required by theMinimum OPERABLE Channels per Trip System requirement for one or both trip systems, place the inoperable channel(s) in the tripped condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or in accordance with the Risk Informed Completion Time Program*.

c. With the number of OPERABLE channels two or more less than requiredby the Minimum OPERABLE Channels per Trip System requirement for one trip system and:

1. If the inoperable channels consist of one reactor vessel waterlevel channel and one reactor vessel pressure channel, place both inoperable channels in the tripped condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or in accordance with the Risk Informed Completion Time Program, or if this action will initiate a pump trip, declare the trip system inoperable.

2. If the inoperable channels or two reactor vessel pressure channels, declare thechannels include two reactor vessel water level trip system inoperable.

d. With one trip system inoperable, restore the inoperable trip systemto OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or in accordance with the Risk Informed Completion Time Program, or be in at least STARTUP within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

e. With both trip systems inoperable, restore at least one trip systemto OPERABLE status within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> or be in at least STARTUP within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

SURVEILLANCE REQUIREMENTS 4.3.4.1.1 Each of the required ATWS recirculation pump trip system instrumentation channels shall be demonstrated OPERABLE by the performance of the CHANNEL CHECK, CHANNEL FUNCTIONAL TEST and CHANNEL CALIBRATION operations at the frequencies specified in the Surveillance Frequency Control Program.

4.3.4.1.2 LOGIC SYSTEM FUNCTIONAL TESTS and simulated automatic operation of all channels shall be performed in accordance with the Surveillance Frequency Control Program.

• Not applicable when trip capability is not maintained.

LIMERICK - UNIT 2 3/4 3-42 Amendment No. 33, 34, 147, 203