NMP1L3614, Response to Request for Additional Information for License Amendment Request to Adopt TSTF-230, Revision 1, Add New Condition B to LCO 3.6.2.3, RHR Suppression Pool Cooling
| ML24327A191 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 11/22/2024 |
| From: | Para W Constellation Energy Generation |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| NMP1L3614 | |
| Download: ML24327A191 (1) | |
Text
200 Energy Way Kennett Square, PA 19348 www.constellation.com 10 CFR 50.90 NMP1L3614 November 22, 2024 United States Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Nine Mile Point Nuclear Station, Unit 1 Renewed Facility Operating License No. DPR-63 NRC Docket No. 50-220
Subject:
Response to Request for Additional Information for License Amendment Request to Adopt TSTF-230, Revision 1, "Add New Condition B to LCO 3.6.2.3, 'RHR Suppression Pool Cooling.'"
References:
- 1.
Letter from D. Gudger (Constellation Energy Generation, LLC) to U.S.
Nuclear Regulatory Commission, "License Amendment Request to Revise Technical Specifications to Adopt TSTF-230, Revision 1, "Add New Condition B to LCO 3.6.2.3, 'RHR Suppression Pool Cooling,'""
dated June 13, 2024 (ML24165A223) 2.
Letter from R. Guzman, Senior Project Manager, U.S. Nuclear Regulatory Commission, "Nine Mile Point Unit 1 - Request for Additional Information - LAR to Revise TSs to Adopt TSTF-230, Revision 1, "Add New Condition B to LCO 3.6.2.3" (EPID L-2024-LLA-0080)," dated November 7, 2024 (ML24312A166)
By letter dated June 13, 2024 (Reference 1), Constellation Energy Generation, LLC (CEG) requested a change the Nine Mile Point Nuclear Station, Unit 1 (NMP1) Technical Specifications (TS) to adopt NRC-approved Technical Specification Task Force (TSTF)
Traveler 230, Revision 1, "Add New Condition B to LCO 3.6.2.3, RHR Suppression Pool Cooling."
On October 31, 2024, the NRC Senior Project Manager for NMP1 emailed CEG a draft Request for Additional Information (RAI) question in support of the NRC's review. On November 5, 2024, a clarification call was conducted with the NRC to ensure understanding of the draft RAI question. On November 7, 2024, the NRC Senior Project Manager issued the final RAI question to CEG (Reference 2). to this letter contains the NRCs RAI question immediately followed by CEGs response. Attachment 2 contains the affected TS markup pages.
CEG has reviewed the information supporting the No Significant Hazards Consideration and the Environmental Consideration that was previously provided to the NRC in Reference 1.
November 22, 2024 Page 2 The additional information provided in this submittal does not affect the conclusion that the proposed license amendment does not involve a significant hazards consideration. This additional information also does not affect the conclusion that neither an environmental impact statement nor an environmental assessment need be prepared in support of the proposed amendment.
In accordance with 10 CFR 50.91, "Notice for public comment; State consultation,"
paragraph (b), CEG is notifying the State of New York of this application for license amendment by transmitting a copy of this letter and its attachments to the designated State Officials.
This letter contains no new regulatory commitments.
Should you have any questions concerning this submittal, please contact Ron Reynolds at 267-533-5698.
I declare under penalty of perjury that the foregoing is true and correct. Executed on the 25th day of November 2024.
Respectfully, Wendi Para Sr. Manager - Licensing Constellation Energy Generation, LLC Attachments:
1.
Request for Additional Information and CEG Responses 2.
Technical Specifications Markup Pages cc:
USNRC Region I, Regional Administrator w/attachment USNRC Senior Resident Inspector, NMP USNRC Project Manager, NMP A. L. Peterson, NYSERDA B. Frymire, NYSPSC A. Kauk, NYSPSC
ATTACHMENT 1 Nine Mile Point Nuclear Station, Unit 1 Renewed Facility Operating License No. DPR-63 Docket No. 50-220 Request for Additional Information and CEG Response
Response to Request for Additional Information Page 1 of 2 NMP1 Adoption of TSTF-230, Revision 1 Docket No. 50-220 Introduction By letter dated June 13, 2024 (ADAMS Accession No. ML24165A223), Constellation Energy Generation, LLC (CEG, the licensee) submitted a license amendment request (LAR) for Nine Mile Point Nuclear Station, Unit No. 1 (NMP1). The licensee proposes adoption of Technical Specification Task Force (TSTF)-230, Revision 1, "Add New Condition B to LCO [Limiting Condition for Operation] 3.6.2.3, RHR Suppression Pool Cooling." The TSTF modifies improved TS (ITS) 3.6.2.3, "Residual Heat Removal (RHR) Suppression Pool Cooling," to allow two RHR suppression pool cooling subsystems to be inoperable for eight hours. NMP1 does not have ITSs; therefore, the applicable LCO for NMP1 is TS LCO 3.3.7, "Containment Spray System."
Additionally, a new Specification is proposed to be added that will direct operators to place the unit in "Shutdown Condition - Hot" within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and "Shutdown Condition - Cold" in 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> if applicable specifications are not met. During its review of the LAR, the NRC staff identified the need for additional information.
Regulatory Basis The regulation at 10 CFR 50.36(c)(2) requires that TSs include LCOs. Per 10 CFR 50.36(c)
(2)(i), LCOs "are the lowest functional capability or performance levels of equipment required for safe operation of the facility." This regulation also requires that when an LCO of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the TS until the condition can be met.
The regulation at Title 10 to the Code of Federal Regulations (10 CFR) Section 50.36(c)(2) requires that TSs include limiting conditions for operation (LCOs). Per 10 CFR 50.36(c)(2) (i),
LCOs "are the lowest functional capability or performance levels of equipment required for safe operation of the facility." The Commissions "Final Policy Statement on Technical Specifications Improvements for Nuclear Power Reactors" (58 FR 39132, dated July 22, 1993) explained that the new STS should also provide improvements to the Bases Section of the specifications, which provides the purpose for each requirement in the specification.
Request for Additional Information The proposed change to NMP1 CSS LCO 3.3.7 in part states, "If both containment spray systems become inoperable, or if one containment spray system and one subsystem in the opposite loop become inoperable, the reactor may remain in operation " (emphasis added).
The proposed change adds new terminology to the CSS LCO 3.7.7 description, for example, "subsystem" and "opposite loop." Similar changes (mark-ups) were provided for the associated NMP1 Bases.
As described in the Commissions policy statement on technical specification improvements, the Bases Section of the specifications clarifies each requirement in the specification. Given that NMP1 uses the CSS for suppression pool cooling and does not have standard specifications, the NRC staff expected the NMP1 Bases for LCO 3.3.7 to explain the proposed new LCO requirements (e.g., what constitutes a CSS subsystem or CSS opposite loop). However, the NMP1 Bases mark-ups did not provide clarifying information. Therefore, the NRC staff requests that the licensee provide information in the NMP1 Bases that clarifies the terminology used in the proposed change to NMP1 CSS LCO 3.3.7.
Response to Request for Additional Information Page 2 of 2 NMP1 Adoption of TSTF-230, Revision 1 Docket No. 50-220 CEG Response to RAI:
As described in Section 3.0 of Reference 1, "Two redundant [containment spray system] CSS loops are provided to remove heat, reduce pressure, and restore the containment pressure suppression system temperature following a LOCA." Each CSS loop includes two redundant trains, consisting of two suction headers, two containment spray pumps, two heat exchangers and the associated containment spray raw water pumps, a common test return line, and associated piping and control valves. The Primary Loop (Loop 11) consists of two trains, 111 Containment Spray pump and its associated components, and 112 Containment Spray pump and its associated components. The Secondary Loop (Loop 12) consists of two trains, 121 Containment Spray pump and its associated components, and 122 Containment Spray pump and its associated components. This description is consistent with the NMP1 Updated Final Safety Analysis Report.
For consistency in terminology, the description of "opposite loop" is revised to "redundant loop" and "subsystem" is revised to "train" on page 160 in TS 3.3.7.e. LCO 3.3.7.e is revised to read as follows:
"If both containment spray system loops become inoperable, or if one containment spray system loop and one train in the redundant loop become inoperable, the reactor may remain in operation for a period not to exceed 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />."
In addition, TS Bases page 162 is revised to clarify terminology and include a description of the CSS loops including their redundant trains.
Revised markups of TS page 160 and TS Bases page162 are provided in Attachment 2.
ATTACHMENT 2 Nine Mile Point Nuclear Station, Unit 1 Renewed Facility Operating License No. DPR-63 Docket No. 50-220 Technical Specifications Markup Pages 160 162
LIMITING CONDITION FOR OPERATION SURVEILLANCE REQUIREMENT
- c.
If a redundant component in each of the containment spray systems or their associated raw water systems become inoperable, both systems shall be considered operable provided that the component is returned to an operable condition within 7 days or in accordance with the Risk Informed Completion Time Program and that the additional surveillance required is performed.
- d.
If a containment spray system or its associated raw water system becomes inoperable and all the components are operable in the other systems, the reactor may remain in operation for a period not to exceed 7 days or in accordance with the Risk Informed Completion Time Program.
- e.
If Specifications "a" or "b" are not met, shutdown shall begin within one hour and the reactor coolant shall be below 215F within ten hours.
If both containment spray systems become inoperable the reactor shall be in the cold shutdown condition within ten hours and no work shall be performed on the reactor which could result in lowering the reactor water level to more than six feet, three inches (-10 inches indicator scale) below minimum normal water level (Elevation 302'9").
- c.
Raw Water Cooling Pumps In accordance with the Surveillance Frequency Control Program, manual startup and operability of the raw water cooling pumps shall be demonstrated.
- d.
Surveillance with Inoperable Components When a component or system becomes inoperable its redundant component or system shall be verified to be operable immediately and in accordance with the Surveillance Frequency Control Program thereafter.
AMENDMENT NO. 142, 222, 250 160 f.
If both containment spray system loops become inoperable, or if one containment spray system loop and one train in the redundant loop become inoperable, the reactor may remain in operation for a period not to exceed 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
If Specifications "a," "b," "c," "d," or "e" are not met, the reactor shall be in the hot shutdown condition within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and 36
BASES FOR 3.3.7 AND 4.3.7 CONTAINMENT SPRAY SYSTEM For reactor coolant temperatures less than 215F not enough steam is generated during a loss-of-coolant accident to pressurize the containment. For reactor coolant temperatures up to 312F, the resultant loss-of-coolant accident pressure would not exceed the design pressure of 35 psig.
Operation of only one containment spray pump is sufficient to provide the required containment spray cooling flow.(1) The specified flow of 3600 gpm at 87.7 psid primary, 89 psid secondary (approximately 95 percent to the drywell and the balance to the suppression chamber) is sufficient to remove post accident core energy released (FSAR Section VII). Requiring both pumps systems operable (400 percent redundancy) will assure the availability of the containment spray system.(1)
Allowable outages are specified to account for components that become inoperable in both systems and for more than one component in a system. Alternatively, a Completion Time can be determined in accordance with the Risk Informed Completion Time Program.
The containment spray raw water cooling system is considered operable when the flow rate is not less than 3000 gpm and the pressure on the raw water side of the containment spray heat exchangers is 10 psig greater than that on the torus water side (not less than 141 psig).
The higher pressure on the raw water side will assure that any leakage is into the containment spray system.
Electrical power for all system components is normally available from the reserve transformer. Upon loss of this service the pumping requirement will be supplied from the diesel generator. At least one diesel generator shall always be available to provide backup electrical power for one containment spray system.
Automatic initiation of the containment spray system assures that the containment will not be overpressurized. This automatic feature would only be required if all core spray systems malfunctioned and significant metal-water reaction occurred. For the normal operation condition of 85F suppression chamber water, containment spray actuation would not be necessary for about 15 minutes.
(1)With two of the containment spray intertie valves open, operation of two containment spray pumps is required to assure the proper flow distribution to the containment spray headers to reduce containment pressure during the first fifteen minutes of the LOCA. Requiring two containment spray pumps to operate reduces the 400 percent redundance of the containment spray system, but there are still six combinations (two out of four pumps) that will assure two pump operation.
AMENDMENT NO. 142, Revision 53 (A250) 162 Add INSERT here
INSERT:
Two redundant containment spray system loops are provided to remove heat, reduce pressure, and restore the containment pressure suppression system temperature following a LOCA. Each containment spray system loop includes two redundant trains, consisting of two suction headers, two containment spray pumps, two heat exchangers and the associated containment spray raw water pumps, a common test return line, and associated piping and control valves.
The Primary Loop (Loop 11) consists of two trains, 111 Containment Spray pump and its associated components, and 112 Containment Spray pump and its associated components.
The Secondary Loop (Loop 12) consists of two trains, 121 Containment Spray pump and its associated components and 122 Containment Spray pump and its associated components.
With both containment spray loops inoperable or one containment spray loop and one train in the redundant loop inoperable, the plant can continue to operate for a period not to exceed 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. In this condition, there is a substantial loss of primary containment pressure and temperature mitigation function. The 8-hour Completion Time is based on this loss of function and is considered acceptable due to the low probability of a DBA and the potential avoidance of a plant shutdown transient that could result in the need for the containment spray system to operate.
If the required Action and associated Completion Time cannot be met, the plant must be brought to an operating condition in which the LCO does not apply. To achieve this status, the plant must be brought to Shutdown Condition-Hot within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and Shutdown Condition-Cold within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner, and without challenging plant systems.