CNL-22-030, Application to Revise Technical Specification 3.4.12, Low Temperature Overpressure Protection System for Sequoyah Nuclear Plant (SQN-TSC-22-01) and TS 3.4.12 Cold Overpressure Mitigation System for Watts Bar Nuclear Plant (WBN-TS-22-03)
| ML22209A002 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar, Sequoyah  |
| Issue date: | 07/27/2022 |
| From: | Jim Barstow Tennessee Valley Authority |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| CNL-22-030 | |
| Download: ML22209A002 (30) | |
Text
1101 Market Street, Chattanooga, Tennessee 37402 CNL-22-030 July 27, 2022 10 CFR 50.90 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555 0001 Sequoyah Nuclear Plant, Units 1 and 2 Renewed Facility Operating License Nos. DPR-77 and DPR-79 NRC Docket Nos. 50-327 and 50-328 Watts Bar Nuclear Plant, Units 1 and 2 Facility Operating License Nos. NPF-90 and NPF-96 NRC Docket Nos. 50-390 and 50-391
Subject:
Application to Revise Technical Specification 3.4.12, Low Temperature Overpressure Protection System for Sequoyah Nuclear Plant (SQN-TSC-22-01) and TS 3.4.12 Cold Overpressure Mitigation System for Watts Bar Nuclear Plant (WBN-TS-22-03)
In accordance with the provisions of Title 10 of the Code of Federal Regulations (10 CFR) 50.90, Application for amendment of license, construction permit, or early site permit, Tennessee Valley Authority (TVA) is submitting a request for an amendment to Renewed Facility Operating License Nos. DPR-77 and DPR-79 for the Sequoyah Nuclear Plant (SQN), Units 1 and 2; and Facility Operating License Nos. NPF-90 and NPF-96 for the Watts Bar Nuclear Plant (WBN), Units 1 and 2, respectively.
This proposed license amendment would add the following note to Technical Specification (TS) 3.4.12, Low Temperature Overpressure Protection (LTOP) System for SQN and TS 3.4.12 Cold Overpressure Mitigation System for WBN.
One safety injection pump and one charging pump may be capable of injecting into the RCS [Reactor Coolant System] for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
The enclosure to this submittal provides a description and assessment of the proposed change, a regulatory evaluation, and a discussion of environmental considerations. .1 provides a marked-up version of the affected pages of SQN Units 1 and 2 TS 3.4.12 showing the proposed changes. Attachment 1.2 provides final typed versions of the SQN TS pages. Attachment 1.3 provides a marked-up version of the SQN Units 1 and 2 TS 3.4.12 Bases. Attachment 2.1 provides a marked-up version of the affected pages of WBN Units 1 and 2 TS 3.4.12 showing the proposed changes. Attachment 2.2 provides final typed versions of the WBN TS pages. Attachment 2.3 provides a marked-up version of
U.S. Nuclear Regulatory Commission CNL-22-030 Page 2 July 27, 2022 the WBN Units 1 and 2 TS 3.4.12 Bases. Changes to the existing TS Bases are provided for information only and will be implemented under the Technical Specification Bases Control Program.
TVA requests approval of the proposed license amendment within one year from the date of this submittal with implementation within 60 days of issuance of the amendment.
TVA 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). In accordance with 10 CFR 50.91(b)(1), TVA is sending a copy of this letter and enclosure to the Tennessee State Department of Environment and Conservation.
There are no new regulatory commitments contained in this letter. If you have any questions regarding this submittal, please contact Stuart L. Rymer, Senior Manager, Fleet Licensing, at slrymer@tva.gov.
I declare under penalty of perjury that the foregoing is true and correct. Executed on this 27th day of July 2022.
Respectfully, Digitally signed by Rearden, Pamela S Date: 2022.07.27 17:32:11 -04'00' James Barstow Vice President, Nuclear Regulatory Affairs & Support Services
Enclosure:
Description and Assessment of the Proposed Change cc (Enclosure):
NRC Regional Administrator - Region II NRC Senior Resident Inspector - Sequoyah Nuclear Plant NRC Senior Resident Inspector - Watts Bar Nuclear Plant NRC Project Manager - Sequoyah Nuclear Plant NRC Project Manager - Watts Bar Nuclear Plant Director, Division of Radiological Health - Tennessee Department of Environment and Conservation
Enclosure Description and Assessment of the Proposed Change
Subject:
Application to Revise Technical Specification 3.4.12, Low Temperature Overpressure Protection System for Sequoyah Nuclear Plant (SQN-TSC-22-01) and TS 3.4.12 Cold Overpressure Mitigation System for Watts Bar Nuclear Plant (WBN-TS-22-03)
CONTENTS 1.0
SUMMARY
DESCRIPTION ............................................................................................... 1
2.0 DETAILED DESCRIPTION ................................................................................................ 1
2.1 SQN System Design and Operation ............................................................................... 1
2.2 WBN System Design and Operation .............................................................................. 2
2.3 Reason for the Proposed Change .................................................................................. 2
2.4 SQN Description of the Proposed Change ..................................................................... 2
2.5 WBN Description of the Proposed Change .................................................................... 3
3.0 TECHNICAL EVALUATION ............................................................................................... 3
4.0 REGULATORY EVALUATION ........................................................................................... 4
4.1 Applicable Regulatory Requirements and Criteria .......................................................... 4
4.2 Precedent ....................................................................................................................... 5
4.3 No Significant Hazards Consideration ............................................................................ 5
4.4 Conclusion ...................................................................................................................... 6
5.0 ENVIRONMENTAL CONSIDERATION ............................................................................. 7
6.0 REFERENCES ................................................................................................................... 7
Attachments 1.1 Proposed TS Changes (Markups) for SQN Units 1 and 2 1.2 Proposed TS Changes (Final Typed) for SQN Units 1 and 2 1.3 Proposed TS Bases Changes (Markups) for SQN Units 1 and 2 (For Information Only) 2.1 Proposed TS Changes (Markups) for WBN Units 1 and 2 2.2 Proposed TS Changes (Final Typed) for WBN Units 1 and 2 2.3 Proposed TS Bases Changes (Markup) for WBN Units 1 and 2 (For Information Only)
CNL-22-030
Enclosure Description and Assessment of the Proposed Change 1.0
SUMMARY
DESCRIPTION In accordance with the provisions of Title 10 of the Code of Federal Regulations (10 CFR) 50.90, Application for amendment of license, construction permit, or early site permit, Tennessee Valley Authority (TVA) is submitting a request for an amendment to Renewed Facility Operating License Nos. DPR-77 and DPR-79 for Sequoyah Nuclear Plant (SQN), Units 1 and 2, and Facility Operating License Nos. NPF-90 and NPF-96 for Watts Bar Nuclear Plant (WBN), Units 1 and 2.
This proposed license amendment will add a note to the limiting condition for operation (LCO) for Technical Specification (TS) 3.4.12, entitled Low Temperature Overpressure Protection (LTOP) System at SQN and Cold Overpressure Mitigation System (COMS) at WBN, as shown below.
One safety injection pump and one charging pump may be capable of injecting into the reactor coolant system [RCS] for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
2.0 DETAILED DESCRIPTION 2.1 SQN System Design and Operation The potential for vessel overpressurization is most acute when the RCS is water solid, occurring only while shutdown; a pressure fluctuation can occur more quickly than an operator can react to relieve the condition. Exceeding the RCS P/T limits by a significant amount could cause brittle cracking of the reactor vessel. LCO 3.4.3, RCS Pressure and Temperature (P/T) Limits, requires administrative control of RCS pressure and temperature during heatup and cooldown to prevent exceeding the Pressure and Temperature Limits Report (PTLR) limits.
TS 3.4.12 provides RCS overpressure protection by having a minimum coolant input capability and having adequate pressure relief capacity. Limiting coolant input capability requires all safety injection pumps and all but one centrifugal charging pump incapable of injection into the RCS and isolating the accumulators. The pressure relief capacity requires either two redundant power-operated relief valves (PORV) or a depressurized RCS and an RCS vent of sufficient size. One PORV or the open RCS vent is the overpressure protection device that acts to terminate an increasing pressure event.
Administrative procedures aid the operator in controlling RCS pressure during low temperature operation. To provide a back-up to the operator and to minimize the possibility of RCS overpressurization, an automatic low temperature over pressure protection (LTOP) system, when manually armed from the main control room, will mitigate the pressure excursion within the allowable pressure limits. The LTOP mitigation system is required only during low temperature operation and is manually enabled for automatic actuation. The LTOP system for pressure relief consists of two PORVs with reduced lift settings, or a depressurized RCS and an RCS vent of sufficient size.
CNL-22-030 E1 of 7
Enclosure 2.2 WBN System Design and Operation The potential for vessel overpressurization is most acute when the RCS is water solid, occurring only while shutdown; a pressure fluctuation can occur more quickly than an operator can react to relieve the condition. Exceeding the RCS P/T limits by a significant amount could cause brittle cracking of the reactor vessel. LCO 3.4.3, "RCS Pressure and Temperature (P/T) Limits,"
requires administrative control of RCS pressure and temperature during heatup and cooldown to prevent exceeding the PTLR limits.
TS 3.4.12 provides RCS overpressure protection by having a minimum coolant input capability and having adequate pressure relief capacity. Limiting coolant input capability requires all safety injection pumps and all but one charging pump incapable of injection into the RCS and isolating the accumulators. The pressure relief capacity requires either two redundant PORVs or a depressurized RCS and an RCS vent of sufficient size. One PORV or the open RCS vent is the overpressure protection device that acts to terminate an increasing pressure event.
Administrative procedures aid the operator in controlling RCS pressure during low temperature operation. To provide a back-up to the operator and to minimize the possibility of RCS overpressurization, an automatic cold overpressure mitigating system (COMS), when manually armed from the main control room, will mitigate the pressure excursion within the allowable pressure limits. The COMS is required only during low temperature operation and is manually enabled for automatic actuation. The COMS for pressure relief consists of two PORVs with reduced lift settings, or one PORV and the Residual Heat Removal (RHR) suction relief valve, or a depressurized RCS and an RCS vent of sufficient size.
2.3 Reason for the Proposed Change This change will provide flexibility in the scheduling of periodic surveillances and critical-path activities during an outage that may involve significant maintenance on safety injection pumps (SIP) and their subsequent required post-maintenance testing.
TS 3.4.12 governs the applicable MODE and plant conditions during the low temperature overpressure protection conditions, permitting one charging pump and no SIPs to be capable of capable of injecting into the RCS. Based on these MODE and plant condition requirements, these pump tests are typically performed with the reactor vessel head off and the refueling cavity flooded providing atmospheric pressure protection conditions and water management control within the refueling cavity.
By allowing the testing of these pumps during the low temperature overpressure protection conditions, outage scheduling flexibility is provided. Likewise, specialized resources supporting the primary/reactor portion of the outage activities can be released from the outage project more rapidly.
2.4 SQN Description of the Proposed Change The LAR proposes the following change to SQN, Units 1 and 2, TS 3.4.12. A new Note 4 would be added to LCO 3.4.12 as shown below. For Unit 2, this new note will replace the note that was added as a one-time change under Amendment 350.
- 4. One safety injection pump and one charging pump may be capable of injecting into the RCS for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is CNL-22-030 E2 of 7
Enclosure on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief. .1 provides a marked-up version of the affected pages of SQN Units 1 and 2 TS 3.4.12 showing the proposed changes. Attachment 1.2 provides final typed versions of the SQN TS pages. Attachment 1.3 provides a marked-up version of the SQN Units 1 and 2 TS 3.4.12 Bases, for information only.
2.5 WBN Description of the Proposed Change The LAR proposes the following change to WBN, Units 1 and 2, TS 3.4.12. A new Note 3 would be added to LCO 3.4.12 as shown below.
- 3. One safety injection pump and one charging pump may be capable of injecting into the RCS for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief. .1 provides a marked-up version of the affected pages of WBN Units 1 and 2 TS 3.4.12 showing the proposed changes. Attachment 2.2 provides final typed versions of the WBN TS pages. Attachment 2.3 provides a marked-up version of the WBN Units 1 and 2 TS 3.4.12 Bases, for information only.
3.0 TECHNICAL EVALUATION
The LTOP system at SQN and the COMS at WBN are designed to protect the RCS from a mass injection (MI) transient equivalent that bounds a charging pump injecting at maximum flow with minimum letdown. This forms the basis of prohibiting the SIP from being capable of injecting during LTOP/COMS applicability via TS LCO 3.4.12.
However, the desired test configuration for a future comprehensive test of a SIP is with the reactor head installed/tensioned. This would mean that the SIP will be capable of injecting to the RCS during the LTOP/COMS LCO 3.4.12 applicability. The LTOP/COMS would have to be capable of relieving the mass input of its design basis transient (the charging pump) in addition to the SIP. To preclude the need for a redesign of the LTOP/COMS system, requiring reanalysis and potentially a revision of the setpoints for the pressurizer (PZR) power-operated relief valve (PORV), the RCS could instead be vented to the containment atmosphere through the PZR manway for the duration that the SIP will be capable of injecting into the RCS.
An analysis for both SQN and WBN was performed to justify that the PZR manway opening is sufficient to prohibit the pressurization of the RCS if a SIP was also capable of injecting during the LTOP/COMS modes of applicability. This conclusion would enable testing of the SIP with the reactor head installed without requiring revision of the PORV setpoints.
This analysis showed that the relief capacity of the PZR manway is more than sufficient to address the combined MI transient of the charging pump and SIP combined.
Accordingly, provided the manway is removed for the duration that the SIP is capable of injecting, and provided the other SIP is not capable of injecting during this time, there will be no overpressure challenge to the safety-related function of maintaining reactor coolant pressure boundary integrity during this configuration.
CNL-22-030 E3 of 7
Enclosure
4.0 REGULATORY EVALUATION
4.1 Applicable Regulatory Requirements and Criteria General Design Criteria SQN Units 1 and 2 were designed to meet the intent of the "Proposed General Design Criteria (GDC)for Nuclear Power Plant Construction Permits published in July 1967. The Sequoyah construction permit was issued in May 1970. The Updated Final Safety Analysis Report (UFSAR), however, addresses the NRC General Design Criteria (GDC) published as Appendix A to 10 CFR 50 in July 1971.
WBN Units 1 and 2 were designed to meet the intent of the "Proposed General Design Criteria for Nuclear Power Plant Construction Permits" published in July 1967. The WBN construction permit was issued in January 1973. The dual-unit UFSAR, however, addresses the Nuclear Regulatory Commission GDC published as Appendix A to 10 CFR 50 in July 1971.
Criterion 14 - Reactor Coolant Pressure Boundary. The reactor coolant pressure boundary shall be designed, fabricated, erected, and tested so as to have an extremely low probability of abnormal leakage or rapidly propagating failure and of gross rupture.
Criterion 15 - Reactor Coolant (RC) System Design. The RC System and associated auxiliary, control, and protection systems shall be designed with sufficient margin to assure that the design conditions of the reactor coolant pressure boundary are not exceeded during any condition of normal operation, including anticipated operational occurrences.
Criterion 31 - Fracture Prevention of Reactor Coolant Pressure Boundary. The reactor coolant pressure boundary shall be designed with sufficient margin to assure that when stressed under operating, maintenance, testing, and postulated accident conditions (1) the boundary behaves in a nonbrittle manner and (2) the probability of rapidly propagating fracture is minimized. The design shall reflect consideration of service temperatures and other conditions of the boundary material under operating, maintenance, testing, and postulated accident conditions and the uncertainties in determining (1) material properties, (2) the effects of irradiation on material properties, (3) residual, steady-state and transient stresses, and (4) size of flaws.
Compliance with GDCs 14, 15, and 31 is described in Section 3.1.2 of the SQN UFSAR, and in Section 3.1.2 of the WBN UFSAR.
With the implementation of the proposed changes, SQN Units 1 and 2 and WBN Units 1 and 2 continue to meet the applicable regulations and requirements, subject to the previously approved exceptions.
CNL-22-030 E4 of 7
Enclosure 4.2 Precedent TVA submitted a one-time license amendment request with the same scope of this request on an exigent basis for SQN Unit 2 in October 2021 (Reference 1). The NRC approved that request in Reference 2.
In addition, NUREG-1431, Revision 5, contains the following wording for TS 3.4.12, Low Temperature Over Protection (LTOP) System.
An LTOP System shall be OPERABLE with a maximum of [one] [high pressure injection (HPI)] pump [and one charging pump] capable of injecting into the RCS and the accumulators isolated and one of the following pressure relief capabilities:
Accordingly, with suitable venting analysis, the Standard Technical Specifications essentially allow what this amendment request proposes.
4.3 No Significant Hazards Consideration TVA is requesting an amendment to Renewed Facility Operating License Nos. DPR-77 and DPR-79 for SQN Units 1 and 2, and Facility Operating License Nos. NPF-90 and NPF-96 for the WBN Units 1 and 2. This proposed license amendment will add a note to the limiting condition for operation (LCO) for Technical Specification (TS) 3.4.12, entitled Low Temperature Overpressure Protection (LTOP) System at SQN and Cold Overpressure Mitigation System (COMS) at WBN, as shown below.
One safety injection pump and one charging pump may be capable of injecting into the RCS
[Reactor Coolant System] for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
TVA has evaluated whether or not a significant hazards consideration is involved with the proposed amendments by focusing on the three standards set forth in 10 CFR 50.92, Issuance of amendment, as discussed below.
- 1. Does the proposed amendment involve a significant increase in the probability or consequence of an accident previously evaluated?
Response: No The safety analysis of the plant is unaffected by the proposed change. Removing the pressurizer manway while a SIP is capable of injecting into the RCS has been shown to provide adequate low-temperature over-pressure protection, and is therefore not a pre-cursor to an accident. Because the safety analysis is unaffected, the calculated radiological releases associated with the analysis are not affected.
Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.
CNL-22-030 E5 of 7
Enclosure
- 2. Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?
Response: No.
The proposed change does not adversely alter the design assumptions, conditions, or configuration of the facility or the manner in which the plant is operated. No new accident scenarios, failure mechanisms, or limiting single failures are introduced as a result of allowing operation of one safety injection pump capable of injecting into the RCS with the RCS depressurized and the pressurizer manway cover removed. The proposed change does not challenge the performance or integrity of any safety-related systems or components.
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 amendment involve a significant reduction in a margin of safety?
Response: No.
The margin of safety is related to the ability of the 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. Removing the pressurizer manway during the post-maintenance testing of the SIP has been shown to provide adequate protection against low-temperature over-pressure of the RCS.
Thus, the performance of the reactor vessel and the reactor coolant system is unaffected by the proposed change.
The margin of safety associated with the acceptance criteria of any accident is unchanged. The proposed change will have no effect on the availability, operability, or performance of safety-related systems and components.
Therefore, the proposed change does not involve a significant reduction in a margin of safety.
Based on the above, TVA 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.
CNL-22-030 E6 of 7
Enclosure
5.0 ENVIRONMENTAL CONSIDERATION
A review 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.
6.0 REFERENCES
- 1. TVA Letter to NRC, "Sequoyah Nuclear Plant, Unit 2 - Exigent License Amendment Request to Revise Technical Specification 3.4.12, Low Temperature Overpressure Protection System (SQN-TS-21-06), dated October 22, 2021 (ML21296A000)
- 2. NRC Letter to TVA, "Sequoyah Nuclear Plant, Unit 2 -- Issuance of Amendment No. 350 Regarding One-Time Change to Technical Specification 3.4.12, Low Temperature Overpressure Protection System," dated October 27, 2021 (ML21298A031)
CNL-22-030 E7 of 7
Enclosure Attachment 1.1 Proposed TS Changes (Markups)
SQN Units 1 and 2 CNL-22-030
LTOP System 3.4.12 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.12 Low Temperature Overpressure Protection (LTOP) System LCO 3.4.12 An LTOP System shall be OPERABLE with a maximum of one charging pump and no safety injection pump capable of injecting into the RCS and the accumulators isolated and one of the following pressure relief capabilities:
- a. Two power operated relief valves (PORVs) with lift settings within the limits specified in the PTLR; or
NOTES-------------------------------------------
- 1. Two charging pumps may be made capable of injecting for d 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for pump swap operations.
- 2. Accumulator may be unisolated when accumulator pressure is less than the maximum RCS pressure for the existing RCS cold leg temperature allowed by the P/T limit curves provided in the PTLR.
- 3. Two safety injection pumps and two charging pumps may be capable of injecting for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after entering MODE 4 from MODE 3 or prior to lowering temperature on any RCS loop below 325°F, whichever occurs first.
- 4. One safety injection pump and one charging pump may be capable of injecting into the RCS for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
APPLICABILITY: MODE 4 when any RCS cold leg temperature is LTOP arming temperature specified in the PTLR, MODE 5, MODE 6 when the reactor vessel head is on.
SEQUOYAH - UNIT 1 3.4.12-1 Amendment 334
LTOP System 3.4.12 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.12 Low Temperature Overpressure Protection (LTOP) System LCO 3.4.12 An LTOP System shall be OPERABLE with a maximum of one charging pump and no safety injection pump capable of injecting into the RCS and the accumulators isolated and one of the following pressure relief capabilities:
- a. Two power operated relief valves (PORVs) with lift settings within the limits specified in the PTLR; or
NOTES-------------------------------------------
- 1. Two charging pumps may be made capable of injecting for d 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for pump swap operations.
- 2. Accumulator may be unisolated when accumulator pressure is less than the maximum RCS pressure for the existing RCS cold leg temperature allowed by the P/T limit curves provided in the PTLR.
- 3. Two safety injection pumps and two charging pumps may be capable of injecting for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after entering MODE 4 from MODE 3 or prior to lowering temperature on any RCS loop below 325°F, whichever occurs first.
- 4. During the Unit 2 Cycle 24 Refueling Outage, for the purpose of testing the 2A-A safety injection pump, the 2A-A safety injection pump and one charging pump may be capable of injecting into the RCS with the RCS depressurized and the pressurizer manway cover removed.
This Note expires when the Unit ascends into MODE 4 from MODE 5.
- 4. One safety injection pump and one charging pump may be capable of injecting into the RCS for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
APPLICABILITY: MODE 4 when any RCS cold leg temperature is LTOP arming temperature specified in the PTLR, MODE 5, MODE 6 when the reactor vessel head is on.
SEQUOYAH - UNIT 2 3.4.12-1 Amendment 327, 350
Enclosure Attachment 1.2 Proposed TS Changes (Final Typed)
SQN Units 1 and 2 CNL-22-030
LTOP System 3.4.12 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.12 Low Temperature Overpressure Protection (LTOP) System LCO 3.4.12 An LTOP System shall be OPERABLE with a maximum of one charging pump and no safety injection pump capable of injecting into the RCS and the accumulators isolated and one of the following pressure relief capabilities:
- a. Two power operated relief valves (PORVs) with lift settings within the limits specified in the PTLR; or
NOTES-------------------------------------------
- 1. Two charging pumps may be made capable of injecting for d 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for pump swap operations.
- 2. Accumulator may be unisolated when accumulator pressure is less than the maximum RCS pressure for the existing RCS cold leg temperature allowed by the P/T limit curves provided in the PTLR.
- 3. Two safety injection pumps and two charging pumps may be capable of injecting for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after entering MODE 4 from MODE 3 or prior to lowering temperature on any RCS loop below 325°F, whichever occurs first.
- 4. One safety injection pump and one charging pump may be capable of injecting into the RCS for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
APPLICABILITY: MODE 4 when any RCS cold leg temperature is LTOP arming temperature specified in the PTLR, MODE 5, MODE 6 when the reactor vessel head is on.
SEQUOYAH - UNIT 1 3.4.12-1 Amendment ___
LTOP System 3.4.12 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.12 Low Temperature Overpressure Protection (LTOP) System LCO 3.4.12 An LTOP System shall be OPERABLE with a maximum of one charging pump and no safety injection pump capable of injecting into the RCS and the accumulators isolated and one of the following pressure relief capabilities:
- a. Two power operated relief valves (PORVs) with lift settings within the limits specified in the PTLR; or
NOTES-------------------------------------------
- 1. Two charging pumps may be made capable of injecting for d 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for pump swap operations.
- 2. Accumulator may be unisolated when accumulator pressure is less than the maximum RCS pressure for the existing RCS cold leg temperature allowed by the P/T limit curves provided in the PTLR.
- 3. Two safety injection pumps and two charging pumps may be capable of injecting for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after entering MODE 4 from MODE 3 or prior to lowering temperature on any RCS loop below 325°F, whichever occurs first.
- 4. One safety injection pump and one charging pump may be capable of injecting into the RCS for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
APPLICABILITY: MODE 4 when any RCS cold leg temperature is LTOP arming temperature specified in the PTLR, MODE 5, MODE 6 when the reactor vessel head is on.
SEQUOYAH - UNIT 2 3.4.12-1 Amendment BBB
Enclosure Attachment 1.3 Proposed TS Bases Changes (Markups)
SQN Units 1 and 2 (For Information Only)
CNL-22-030
LTOP System B 3.4.12 BASES APPLICABLE SAFETY ANALYSES (continued)
RCS Vent Performance With the RCS depressurized, analyses show a vent size of 3.0 square inches is capable of mitigating the allowed LTOP overpressure transient.
The capacity of a vent this size is greater than the flow of the limiting transient for the LTOP configuration, one charging pump OPERABLE, maintaining RCS pressure less than the maximum pressure on the P/T limit curve.
The RCS vent size will be re-evaluated for compliance each time the P/T limit curves are revised based on the results of the vessel material surveillance.
The RCS vent is passive and is not subject to active failure.
The LTOP System satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii).
LCO This LCO requires that the LTOP System is OPERABLE. The LTOP System is OPERABLE when the minimum coolant input and pressure relief capabilities are OPERABLE. Violation of this LCO could lead to the loss of low temperature overpressure mitigation and violation of the Reference 1 limits as a result of an operational transient.
To limit the coolant input capability, the LCO requires that no safety injection pumps and a maximum of one charging pump be capable of injecting into the RCS, and all accumulator discharge isolation valves be closed and immobilized (when accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature allowed in the PTLR).
IRXU The LCO is modified by three Notes. Note 1 allows two charging pumps to be made capable of injecting for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> during pump swap operations. One hour provides sufficient time to safely complete the actual transfer and to complete the administrative controls and Surveillance Requirements associated with the swap. The intent is to minimize the actual time that more than one charging pump is physically capable of injection. Note 2 states that accumulator isolation is only required when the accumulator pressure is more than or at the maximum RCS pressure for the existing temperature, as allowed by the P/T limit curves. This Note permits the accumulator discharge isolation valve Surveillance to be performed only under these pressure and temperature conditions. Note 3 allows a 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> maximum time period for rendering both safety injection and one centrifugal charging pump inoperable after entry in MODE 4 from MODE 3. RCS temperature must remain above 325°F until the pumps are rendered incapable of inadvertent injection.
SEQUOYAH - UNIT 1 B 3.4.12-6 Revision 45
1RWHDOORZVRQHVDIHW\LQMHFWLRQSXPSDQGRQHFKDUJLQJSXPSWREHFDSDEOH RILQMHFWLQJLQWRWKH5&6IRUWKHSXUSRVHRIWHVWLQJLQ02'(RU02'( LTOP System ZKHQWKHUHDFWRUYHVVHOKHDGLVRQSURYLGHGWKHSUHVVXUL]HUPDQZD\FRYHULV B 3.4.12 UHPRYHGWRSURYLGHDYHQWSDWKIRUDGHTXDWHSUHVVXUHUHOLHI
BASES LCO (continued)
The 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> time period is sufficient for completing this activity and is based on low probability for inadvertent pump start.
The elements of the LCO that provide low temperature overpressure mitigation through pressure relief are:
- a. Two OPERABLE PORVs, A PORV is OPERABLE for LTOP when its block valve is open, its lift setpoint is set to the limit required by the PTLR and testing proves its ability to open at this setpoint, and motive power is available to the two valves and their control circuits.
An RCS vent is OPERABLE when open with an area of 3.0 square inches.
Each of these methods of overpressure prevention is capable of mitigating the limiting LTOP transient.
APPLICABILITY This LCO is applicable in MODE 4 when any RCS cold leg temperature is the LTOP arming temperature specified in the PTLR, in MODE 5, and in MODE 6 when the reactor vessel head is on. The pressurizer safety valves provide overpressure protection that meets the Reference 1 P/T limits above the LTOP arming temperature specified in the PTLR. When the reactor vessel head is off, overpressurization cannot occur.
LCO 3.4.3 provides the operational P/T limits for all MODES.
LCO 3.4.10, "Pressurizer Safety Valves," requires the OPERABILITY of the pressurizer safety valves that provide overpressure protection during MODES 1, 2, and 3.
Low temperature overpressure prevention is most critical during shutdown when the RCS is water solid, and a mass or heat input transient can cause a very rapid increase in RCS pressure when little or no time allows operator action to mitigate the event.
ACTIONS A Note prohibits the application of LCO 3.0.4.b to an inoperable LTOP System. There is an increased risk associated with entering MODE 4 from MODE 5 with LTOP inoperable and the provisions of LCO 3.0.4.b, which allow entry into a MODE or other specified condition in the Applicability with the LCO not met after performance of a risk assessment addressing inoperable systems and components, should not be applied in this circumstance.
SEQUOYAH - UNIT 1 B 3.4.12-7 Revision 45
LTOP System B 3.4.12 BASES APPLICABLE SAFETY ANALYSES (continued)
RCS Vent Performance With the RCS depressurized, analyses show a vent size of 3.0 square inches is capable of mitigating the allowed LTOP overpressure transient.
The capacity of a vent this size is greater than the flow of the limiting transient for the LTOP configuration, one charging pump OPERABLE, maintaining RCS pressure less than the maximum pressure on the P/T limit curve.
The RCS vent size will be re-evaluated for compliance each time the P/T limit curves are revised based on the results of the vessel material surveillance.
The RCS vent is passive and is not subject to active failure.
The LTOP System satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii).
LCO This LCO requires that the LTOP System is OPERABLE. The LTOP System is OPERABLE when the minimum coolant input and pressure relief capabilities are OPERABLE. Violation of this LCO could lead to the loss of low temperature overpressure mitigation and violation of the Reference 1 limits as a result of an operational transient.
To limit the coolant input capability, the LCO requires that no safety injection pumps and a maximum of one charging pump be capable of injecting into the RCS, and all accumulator discharge isolation valves be closed and immobilized (when accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature allowed in the PTLR).
The LCO is modified by four Notes. Note 1 allows two charging pumps to be made capable of injecting for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> during pump swap operations. One hour provides sufficient time to safely complete the actual transfer and to complete the administrative controls and Surveillance Requirements associated with the swap. The intent is to minimize the actual time that more than one charging pump is physically capable of injection. Note 2 states that accumulator isolation is only required when the accumulator pressure is more than or at the maximum RCS pressure for the existing temperature, as allowed by the P/T limit curves. This Note permits the accumulator discharge isolation valve Surveillance to be performed only under these pressure and temperature conditions. Note 3 allows a 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> maximum time period for rendering both safety injection and one centrifugal charging pump inoperable after entry in MODE 4 from MODE 3. RCS temperature must remain above 325°F until the pumps are rendered incapable of inadvertent injection.
SEQUOYAH - UNIT 2 B 3.4.12-6 Revision 65
1RWHDOORZVRQHVDIHW\LQMHFWLRQSXPSDQGRQHFKDUJLQJSXPSWREHFDSDEOH RILQMHFWLQJLQWRWKH5&6IRUWKHSXUSRVHRIWHVWLQJLQ02'(RU02'(
LTOP System ZKHQWKHUHDFWRUYHVVHOKHDGLVRQSURYLGHGWKHSUHVVXUL]HUPDQZD\FRYHULV B 3.4.12 UHPRYHGWRSURYLGHDYHQWSDWKIRUDGHTXDWHSUHVVXUHUHOLHI
BASES LCO (continued)
The 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> time period is sufficient for completing this activity and is based on low probability for inadvertent pump start. Note 4 allows during the Unit 2 Cycle 24 Refueling Outage, for the purpose of testing the 2A-A safety injection pump, the 2A-A safety injection pump and one charging pump may be capable of injecting into the RCS with the RCS depressurized and the pressurizer manway cover removed. This Note expires when the Unit ascends into MODE 4 from MODE 5.
The elements of the LCO that provide low temperature overpressure mitigation through pressure relief are:
- a. Two OPERABLE PORVs, A PORV is OPERABLE for LTOP when its block valve is open, its lift setpoint is set to the limit required by the PTLR and testing proves its ability to open at this setpoint, and motive power is available to the two valves and their control circuits.
An RCS vent is OPERABLE when open with an area of 3.0 square inches.
Each of these methods of overpressure prevention is capable of mitigating the limiting LTOP transient.
APPLICABILITY This LCO is applicable in MODE 4 when any RCS cold leg temperature is the LTOP arming temperature specified in the PTLR, in MODE 5, and in MODE 6 when the reactor vessel head is on. The pressurizer safety valves provide overpressure protection that meets the Reference 1 P/T limits above the LTOP arming temperature specified in the PTLR. When the reactor vessel head is off, overpressurization cannot occur.
LCO 3.4.3 provides the operational P/T limits for all MODES.
LCO 3.4.10, "Pressurizer Safety Valves," requires the OPERABILITY of the pressurizer safety valves that provide overpressure protection during MODES 1, 2, and 3.
Low temperature overpressure prevention is most critical during shutdown when the RCS is water solid, and a mass or heat input transient can cause a very rapid increase in RCS pressure when little or no time allows operator action to mitigate the event.
ACTIONS A Note prohibits the application of LCO 3.0.4.b to an inoperable LTOP System. There is an increased risk associated with entering MODE 4 SEQUOYAH - UNIT 2 B 3.4.12-7 Revision 65
Enclosure Attachment 2.1 Proposed TS Changes (Markups)
WBN Units 1 and 2 CNL-22-030
COMS 3.4.12 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.12 Cold Overpressure Mitigation System (COMS)
LCO 3.4.12 A COMS System shall be OPERABLE with a maximum of one charging pump and no safety injection pump capable of injecting into the RCS and the accumulators isolated and either a or b below.
- a. Two RCS relief valves, as follows:
- 1. Two power operated relief valves (PORVs) with lift settings within the limits specified in the PTLR, or
- 2. One PORV with a lift setting within the limits specified in the PTLR and the RHR suction relief valve with a setpoint t 436.5 psig and d 463.5 psig.
NOTES-------------------------------------------------------------
- 1. Two charging pumps may be made capable of injecting for less than or equal to one hour for pump swap operations.
- 2. Accumulator may be unisolated when accumulator pressure is less than the maximum RCS Pressure for the existing RCS cold leg temperature allowed by the P/T limit curves provided in the PTLR.
- 3. One safety injection pump and one charging pump may be capable of injecting into the RCS for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
APPLICABILITY: MODES 4 and 5, MODE 6 when the reactor vessel head is on.
Watts Bar-Unit 1 3.4-25 Amendment 55
COMS 3.4.12 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.12 Cold Overpressure Mitigation System (COMS)
LCO 3.4.12 A COMS System shall be OPERABLE with a maximum of one charging pump and no safety injection pump capable of injecting into the RCS and the accumulators isolated and either a or b below.
- a. Two RCS relief valves, as follows:
- 1. Two power operated relief valves (PORVs) with lift settings within the limits specified in the PTLR, or
- 2. One PORV with a lift setting within the limits specified in the PTLR and the RHR suction relief valve with a setpoint t 436.5 psig and d 463.5 psig.
> 475 gpm water flow.
NOTE--------------------------------------------
- 1. Two charging pumps may be made capable of injecting for less than or equal to one hour for pump swap operations.
- 2. Accumulator may be unisolated when accumulator pressure is less than the maximum RCS pressure for the existing RCS cold leg temperature allowed by the P/T limit curves provided in the PTLR.
- 3. One safety injection pump and one charging pump may be capable of injecting into the RCS for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
APPLICABILITY: MODE 4 with any RCS cold leg temperature d to the COMS arming temperature specified in the PTLR, MODE 5, MODE 6 when the reactor vessel head is on.
Watts Bar - Unit 2 3.4-23 Amendment
Enclosure Attachment 2.2 Proposed TS Changes (Final Typed)
WBN Units 1 and 2 CNL-22-030
COMS 3.4.12 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.12 Cold Overpressure Mitigation System (COMS)
LCO 3.4.12 A COMS System shall be OPERABLE with a maximum of one charging pump and no safety injection pump capable of injecting into the RCS and the accumulators isolated and either a or b below.
D Two RCS relief valves, as follows:
Two power operated relief valves (PORVs) with lift settingswithin the limits specified in the PTLR, or
One PORV with a lift setting within the limits specified in thePTLR and the RHR suction relief valve with a setpoint t 436.5 psig and d 463.5 psig.
E The RCS depressurized and an RCS vent capable of relieving > 475JSP
water flow.
NOTES-------------------------------------------------------------
- 1. Two charging pumps may be made capable of injecting for less than or equal to one hour for pump swap operations.
- 2. Accumulator may be unisolated when accumulator pressure is less than the maximum RCS Pressure for the existing RCS cold leg temperature allowed by the P/T limit curves provided in the PTLR.
- 3. One safety injection pump and one charging pump may be capable of injecting into the RCS for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
APPLICABILITY: MODES 4 and 5, MODE 6 when the reactor vessel head is on.
Watts Bar-Unit 1 3.4-25 Amendment ____
COMS 3.4.12 3.4 REACTOR COOLANT SYSTEM (RCS) 3.4.12 Cold Overpressure Mitigation System (COMS)
LCO 3.4.12 A COMS System shall be OPERABLE with a maximum of one charging pump and no safety injection pump capable of injecting into the RCS and the accumulators isolated and either a or b below.
- a. Two RCS relief valves, as follows:
- 1. Two power operated relief valves (PORVs) with lift settings within the limits specified in the PTLR, or
- 2. One PORV with a lift setting within the limits specified in the PTLR and the RHR suction relief valve with a setpoint t 436.5 psig and d 463.5 psig.
> 475 gpm water flow.
NOTE--------------------------------------------
- 1. Two charging pumps may be made capable of injecting for less than or equal to one hour for pump swap operations.
- 2. Accumulator may be unisolated when accumulator pressure is less than the maximum RCS pressure for the existing RCS cold leg temperature allowed by the P/T limit curves provided in the PTLR.
- 3. One safety injection pump and one charging pump may be capable of injecting into the RCS for the purpose of testing in MODE 5 or MODE 6 when the reactor vessel head is on, provided the pressurizer manway cover is removed to provide a vent path for adequate pressure relief.
APPLICABILITY: MODE 4 with any RCS cold leg temperature d to the COMS arming temperature specified in the PTLR, MODE 5, MODE 6 when the reactor vessel head is on.
Watts Bar - Unit 2 3.4-23 Amendment ____
Enclosure Attachment 2.3 Proposed TS Bases Changes (Markups)
WBN Units 1 and 2 (For Information Only)
CNL-22-030
COMS B 3.4.12 BASES APPLICABLE RCS Vent Performance (continued)
SAFETY ANALYSES The RCS vent size will be re-evaluated for compliance each time the P/T limit curves are revised based on the results of the vessel material surveillance. The RCS vent is passive and is not subject to active failure.
The COMS satisfies Criterion 2 of the NRC Policy Statement.
LCO This LCO requires that the COMS is OPERABLE. The COMS is OPERABLE when the minimum coolant input and pressure relief capabilities are OPERABLE.
Violation of this LCO could lead to the loss of low temperature overpressure mitigation and violation of the Reference 1 limits as a result of an operational transient.
To limit the coolant input capability, the LCO requires no safety injection pumps and a maximum of one charging pump be capable of injecting into the RCS, and all accumulator discharge isolation valves be closed and immobilized when accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature allowed in the PTLR.
WKUHH The LCO is modified by two Notes. Note 1 allows two charging pumps to be made capable of injecting for less than or equal to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> during pump swap operations. One hour provides sufficient time to safely complete the actual transfer and to complete the administrative controls and surveillance requirements associated with the swap. The intent is to minimize the actual time that more than one charging pump is physically capable of injection.
Note 2 states that accumulator isolation is only required when the accumulator pressure is more than or at the maximum RCS pressure for the existing temperature, as allowed by the P/T limit curves. This Note permits the accumulator discharge isolation valve Surveillance to be performed only under these pressure and temperature conditions.
The elements of the LCO that provide low temperature overpressure mitigation through pressure relief are:
- a. Two RCS relief valves, as follows:
1RWHDOORZVRQHVDIHW\LQMHFWLRQSXPSDQGRQHFKDUJLQJSXPSWREHFDSDEOH RILQMHFWLQJLQWRWKH5&6IRUWKHSXUSRVHRIWHVWLQJLQ02'(RU02'(
ZKHQWKHUHDFWRUYHVVHOKHDGLVRQSURYLGHGWKHSUHVVXUL]HUPDQZD\FRYHULV UHPRYHGWRSURYLGHDYHQWSDWKIRUDGHTXDWHSUHVVXUHUHOLHI
(continued)
Watts Bar-Unit 1 B 3.4-58 Revision 68 Amendment 55
COMS B 3.4.12 BASES (continued)
LCO This LCO requires that the COMS is OPERABLE. The COMS is OPERABLE when the minimum coolant input and pressure relief capabilities are OPERABLE. Violation of this LCO could lead to the loss of low temperature overpressure mitigation and violation of the Reference 1 limits as a result of an operational transient.
To limit the coolant input capability, the LCO requires no safety injection pumps and a maximum of one charging pump be capable of injecting into the RCS, and all accumulator discharge isolation valves be closed and immobilized when accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature allowed in the PTLR.
WKUHH The LCO is modified by two Notes. Note 1 allows two charging pumps to be made capable of injecting for less than or equal to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> during pump swap operations. One hour provides sufficient time to safely complete the actual transfer and to complete the administrative controls and surveillance requirements associated with the swap. The intent is to minimize the actual time that more than one charging pump is physically capable of injection.
Note 2 states that accumulator isolation is only required when the accumulator pressure is more than or at the maximum RCS pressure for the existing temperature, as allowed by the P/T limit curves. This Note permits the accumulator discharge isolation valve Surveillance to be performed only under these pressure and temperature conditions.
The elements of the LCO that provide low temperature overpressure mitigation through pressure relief are:
- a. Two RCS relief valves, as follows:
1RWHDOORZVRQHVDIHW\ 1. Two OPERABLE PORVs; or LQMHFWLRQSXPSDQGRQH
A PORV is OPERABLE for COMS when its block valve is open, FKDUJLQJSXPSWREHFDSDEOH
its lift setpoint is set to the limit required by the PTLR and testing RILQMHFWLQJLQWRWKH5&6IRU
proves its ability to open at this setpoint, and motive power is WKHSXUSRVHRIWHVWLQJLQ available to the valve and its control circuit.
02'(RU02'(ZKHQ
WKHUHDFWRUYHVVHOKHDGLVRQ 2. One OPERABLE PORV and the OPERABLE RHR suction relief SURYLGHGWKHSUHVVXUL]HU valve; or PDQZD\FRYHULVUHPRYHGWR
SURYLGHDYHQWSDWKIRU An RHR suction relief valve is OPERABLE for COMS when both DGHTXDWHSUHVVXUHUHOLHI RHR suction isolation valves are open, its setpoint is at or between 436.5 psig and 463.5 psig, and testing has proven its ability to open at this setpoint.
(continued)
Watts Bar - Unit 2 B 3.4-58