ML19028A286
| ML19028A286 | |
| Person / Time | |
|---|---|
| Site: | Technical Specifications Task Force |
| Issue date: | 02/21/2019 |
| From: | Victor Cusumano NRC/NRR/DSS/STSB |
| To: | Technical Specifications Task Force |
| Honcharik M, NRR/DSS, 301-415-1774 | |
| Shared Package | |
| ML19028A288 | List: |
| References | |
| Download: ML19028A286 (8) | |
Text
General Directions: This Model safety evaluation (SE) provides the format and content to be used when preparing the plant-specific SE of a license amendment request to adopt TSTF-566, Revision 0. The bolded bracketed information shows text that should be filled in for the specific amendment; individual licensees would furnish site-specific nomenclature or values for these bracketed items. The italicized wording provides guidance on what should be included in each section and should not be included in the SE.
FINAL MODEL SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION TECHNICAL SPECIFICATIONS TASK FORCE TRAVELER TSTF-566, REVISION 0 REVISE ACTIONS FOR INOPERABLE RHR SHUTDOWN COOLING SUBSYSTEM USING THE CONSOLIDATED LINE ITEM IMPROVEMENT PROCESS
1.0 INTRODUCTION
By application dated [enter date], (Agencywide Documents Access and Management System (ADAMS) Accession No. [MLXXXXXXXXX]), [as supplemented by letters dated [enter date(s))), [name of licensee] (the licensee) submitted a license amendment request (LAR) for
[name of facility (abbreviated name), applicable units]. The amendment would revise technical specification (TS) actions for inoperable residual heat removal (RHR) shutdown cooling subsystems in the RHR shutdown cooling system limiting conditions for operation (LCOs).
The proposed changes are based on Technical Specifications Task Force (TSTF) traveler TSTF-566, Revision 0, Revise Actions for Inoperable RHR Shutdown Cooling Subsystems, dated January 19, 2018 (ADAMS Accession No. ML18019B187). The U.S. Nuclear Regulatory Commission (NRC or the Commission) issued a final safety evaluation (SE) approving TSTF-566, Revision 0, on [enter date] (ADAMS Accession No. ML19028A287).
[The licensee has proposed variations from the TS changes described in TSTF-566, Revision 0. The variations are described in Section [2.2.1] of this SE and evaluated in Section [3.3)). OR [The licensee is not proposing any variations from the TS changes described in TSTF-566 or the applicable parts of the NRC staffs SE of TSTF-566.))
[The supplemental letters dated [enter date(s)], provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the NRC staffs original proposed no significant hazards consideration determination as published in the Federal Register on [enter date] (cite FR reference).]
Enclosure 2
2.0 REGULATORY EVALUATION
2.1 DESCRIPTION
OF RESIDUAL HEAT REMOVAL SHUTDOWN COOLING SYSTEM
{NOTE: Technical reviewers and/or the project manager should verify that the RHR shutdown cooling system description is applicable to this plant and revise this section if necessary.}
Irradiated fuel in the shutdown reactor core generates heat during the decay of fission products and increases the temperature of the reactor coolant. This decay heat must be removed to reduce the temperature of the reactor coolant to less than or equal to 200 degrees Fahrenheit
(°F). This decay heat is removed by the RHR shutdown cooling system in preparation for performing refueling or maintenance operations, or for keeping the reactor in the hot shutdown condition or cold shutdown condition.
The two redundant, manually controlled shutdown cooling subsystems of the RHR system provide decay heat removal. Each of the two shutdown cooling subsystems of the RHR system can provide the required decay heat removal. Each RHR shutdown cooling subsystem consists of one or two motor-driven pumps, a heat exchanger, and associated piping and valves. The RHR heat exchangers transfer heat to the RHR service water system. Some piping and heat exchangers that are passive components may be common to both subsystems.
Technical Specification [3.4.8], Residual Heat Removal (RHR) Shutdown Cooling System -
Hot Shutdown, is applicable on Mode 3 [with reactor steam dome pressure lower than the RHR cut-in permissive] pressure. Technical Specification [3.4.9], Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown, is applicable in Mode 4. They both require two operable RHR shutdown cooling subsystems and, with no recirculation pump in operation, at least one RHR shutdown cooling subsystem in operation.
2.2 PROPOSED CHANGE
S TO THE TECHNICAL SPECIFICATIONS The licensee proposed to revise TS actions for inoperable RHR shutdown cooling subsystems in the RHR shutdown cooling system LCOs, consistent with TSTF-566, Revision 0.
The proposed changes would revise TS [3.4.8], Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown, and [3.4.9], Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown, for [Name of facility]. The proposed changes are described below.
2.2.1 Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown Required actions for one or two RHR shutdown cooling subsystems inoperable (Condition A) of
[Name of facility] TS [3.4.8], Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown, require the operators to initiate action to restore RHR shutdown cooling subsystem(s) to operable status (Required Action A.1) immediately, verify an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem (Required Action A.2) within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, and be in Mode 4 (Required Action A.3) within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
The licensee proposed to move Required Action A.1 to new Condition B (as Required Action B.1) and delete Required Action A.3. The LAR also proposed to add a recurring
completion time (CT) to current Required Action A.2 of once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> thereafter. The proposed changes also renumber current Required Action A.2 as A.1 since Required Actions A.1 and A.3 are removed from Condition A.
The licensee also proposed a new Condition B for when the required action and associated CT of Condition A are not met. New Condition Bs Required Action B.1 is moved from current Required Action A.1 and requires operators to initiate action to restore RHR shutdown cooling subsystems(s) to operable status immediately.
Current Required Action A.2 was renumbered as A.1, since Required Actions A.1 and A.3 were deleted. Current Condition B and its required actions were renamed C, C.1, C.2, and C.3, respectively, since new Condition B was added.
2.2.2 Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown Required actions for one or two RHR shutdown cooling subsystems inoperable (Condition A) of TS [3.4.9], Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown, require the operators to verify an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem (Required Action A.1) within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> thereafter.
The licensee proposed a new Condition B for when the required action and associated CT of Condition A are not met which has a required action (new Required Action B.1) for operators to initiate action to restore RHR shutdown cooling subsystems(s) to operable status immediately.
Current Condition B and its required actions were renamed C, C.1, and C.2, respectively, since new Condition B was added.
2.2.1 Variations from TSTF-566
{NOTE: Technical reviewers and/or the project manager are to assess the adequacy of any variations from the approved traveler and document their acceptability. Choose the applicable paragraphs based on information provided in the LAR.}
[The licensee is proposing the following variations from the TS changes described in TSTF-566 or the applicable parts of the NRC staffs SE of TSTF-566. [Describe the variations and why TSTF-566 is still applicable.] These variations do not affect the applicability of TSTF-566 or the NRC staff's SE to the proposed LAR.]
[The [PLANT] TSs utilize different [numbering][and][titles] than the Standard Technical Specifications (STS) on which TSTF-566 was based. Specifically, [describe differences between the plant-specific TS numbering and/or titles and the TSTF-566 numbering and/or titles.] These differences are editorial and do not affect the applicability of TSTF-566 to the proposed LAR.]
[The [PLANT] design is different than the model plant assumed in the Standard Technical Specifications, but the TSTF-566 justification and the NRC staff's SE are still applicable.
[Describe differences and why TSTF-566 is still applicable.))
2.3 APPLICABLE REGULATORY REQUIREMENTS AND GUIDANCE Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36(a)(1) requires each applicant for a license authorizing operation of a utilization facility to include in the application proposed TSs.
The regulation at 10 CFR 50.36(b) requires:
Each license authorizing operation of a utilization facility will include technical specifications. The technical specifications will be derived from the analyses and evaluation included in the safety analysis report, and amendments thereto, submitted pursuant to [10 CFR] 50.34 [Contents of applications; technical information]. The Commission may include such additional technical specifications as the Commission finds appropriate.
The regulation at 10 CFR 50.40(a) states, in part, that the TS shall provide reasonable assurance that the health and safety of the public will not be endangered.
The regulation at 10 CFR 50.36(a)(1) states, in part: A summary statement of the bases or reasons for such specifications, other than those covering administrative controls, shall also be included in the application, but shall not become part of the technical specifications.
The NRC staffs guidance for the review of TSs is in Chapter 16.0, Technical Specifications, of NUREG-0800, Revision 3, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants, LWR [Light-Water Reactor] Edition (SRP), March 2010 (ADAMS Accession No. ML100351425). As described therein, as part of the regulatory standardization effort, the NRC staff has prepared Standard Technical Specifications (STS) for each of the LWR nuclear designs. Accordingly, the NRC staffs review includes consideration of whether the proposed changes are consistent with the applicable reference STS (i.e., the current STS), as modified by NRC-approved travelers.
{NOTE: Choose applicable STS}
[U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric BWR/4 Plants, NUREG-1433, Volume 1, Specifications, and Volume 2, Bases, Revision 4.0, April 2012 (ADAMS Accession Nos. ML12104A192 and ML12104A193, respectively).
U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric BWR/6 Plants, NUREG-1434, Volume 1, Specifications, and Volume 2, Bases, Revision 4.0, April 2012 (ADAMS Accession Nos. ML12104A195 and ML12104A196, respectively).]
3.0 TECHNICAL EVALUATION
3.1 PROPOSED CHANGE
S TO RESIDUAL HEAT REMOVAL (RHR) SHUTDOWN COOLING SYSTEM - HOT SHUTDOWN The licensee proposed to modify TS [3.4.8], Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown. The technical evaluation of each change follows.
3.1.1 Evaluation of Changes to Condition A The licensee proposed to add a recurring CT to current Required Action A.2 of once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> thereafter. Current Required Action A.2 requires verification that an alternate method of decay heat removal is available for each inoperable RHR shutdown cooling subsystem within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. The NRC staff finds this change is acceptable, since it requires continuous verification of alternate methods of decay heat removal every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and provides assurance of continued heat removal capability.
The licensee also proposed to delete current Required Action A.3, which requires the plant to be in Mode 4 within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> when one or two RHR shutdown cooling subsystems are inoperable.
Current Required Action A.3 requires operators to reduce the reactor coolant system temperature to the point where Mode 4 is entered, due to the potentially reduced reliability of the alternate methods of decay heat removal. However, if there is no operable RHR shutdown cooling subsystem and the plant is in a period of high decay heat load, it may not be possible to reduce the reactor coolant system temperature to the Mode 4 entry condition (typically less than 200 °F) within the CT. In addition, in a typical BWR design, the RHR shutdown cooling system has a heat rejection capability many times greater than alternate methods available. Therefore, for periods in which there is high decay heat load, the BWR design does not include any system which can satisfy Required Action A.3. The NRC staff finds the deletion of current Required Action A.3 is acceptable because, at below the RHR cut in permissive pressure, the remaining required action will continue to transfer fission product decay heat and other residual heat from the reactor core at a rate such that specified acceptable fuel design limits and the design conditions of the reactor coolant pressure boundary are not exceeded.
Current Required Action A.2 is renumbered as A.1, since Required Actions A.1 and A.3 are removed from Condition A. The NRC staff finds this change is acceptable since it provides the correct number sequence.
3.1.2 Evaluation of New Condition B The licensee proposed a new Condition B for when the required action and associated CT of Condition A is not met. New Condition Bs required action, B.1, is moved from current Required Action A.1 and requires operators to initiate action to restore RHR shutdown cooling subsystems(s) to operable status immediately. The NRC staff finds that relocating the required action from A.1 to new Required Action B.1 is acceptable because other ways of removing decay heat are available, such as natural circulation, the spent fuel pool cooling system, the reactor water cleanup system and an inoperable, but functional, RHR shutdown cooling subsystem.
If an alternate method cannot be established (Condition A), new Condition B requires the licensee to immediately initiate action to restore the inoperable RHR shutdown cooling subsystem(s) to operable status. The CT immediately is defined in Section 1.3 of the [Name of facility]s TSs as, the Required Action should be pursued without delay and in a controlled manner. New Required Action B.1 continues to apply until the inoperable RHR shutdown cooling subsystems are restored to operable status, an alternate decay heat removal method is established, or the specification is exited.
The NRC staff finds this change is acceptable because new Condition B, with its Required Action B.1, provides an appropriate terminal action for when an alternate method cannot be established within the CT. In addition, new Required Action B.1 will restore redundant decay
heat removal paths and the immediate CT reflects the importance of maintaining the availability of two paths for heat removal.
3.1.3 Evaluation of Changes to Existing Condition B Current Required Action A.2 was renumbered as A.1, since Required Actions A.1 and A.3 were deleted. Current Condition B and its required actions were renamed C, C.1, C.2, and C.3, respectively, since new Condition B was added. The NRC staff finds this change is acceptable since it provides the correct number sequence.
3.1.4 Conclusion of Proposed Changes to Residual Heat Removal (RHR)
Shutdown Cooling System - Hot Shutdown The NRC staff concludes the proposed changes are acceptable since the TS continue to meet the requirements of 10 CFR 50.40(a) because it provides reasonable assurance that the health and safety of the public will not be endangered.
3.2 PROPOSED CHANGE
S TO RESIDUAL HEAT REMOVAL (RHR)
SHUTDOWN COOLING SYSTEM - COLD SHUTDOWN The licensee proposed to modify TS [3.4.9], Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown. The technical evaluation of each change follows.
3.2.1 Evaluation of New Condition B The licensee proposed a new Condition B for when the required action and associated CT of Condition A is not met which has a required action (new Required Action B.1) for operators to initiate action to restore RHR shutdown cooling subsystems(s) to operable status immediately.
If an alternate method cannot be established (Condition A), new Condition B requires the licensee to immediately initiate action to restore the inoperable RHR shutdown cooling subsystem(s) to operable status. The CT immediately is defined in Section 1.3 of the TSs as, the Required Action should be pursued without delay and in a controlled manner. New Required Action B.1 continues to apply until the inoperable RHR shutdown cooling subsystems are restored to operable status, an alternate decay heat removal method is established, or the specification is exited.
The NRC staff finds this change is acceptable because new Condition B with its Required Action B.1 provide an appropriate terminal action for when an alternate method cannot be established within the CT. In addition, new Required Action B.1 will restore redundant decay heat removal paths and the immediate CT reflects the importance of maintaining the availability of two paths for heat removal.
3.2.2 Evaluation of Changes to Existing Condition B Current Condition B and its required actions were renamed C, C.1, and C.2, respectively, since new Condition B was added. The NRC staff finds this change is acceptable since it provides the correct number sequence.
3.2.3 Conclusion of Proposed Changes to Residual Heat Removal (RHR)
Shutdown Cooling System - Cold Shutdown The NRC staff concludes the proposed changes are acceptable since the TS continues to meet the requirements of 10 CFR 50.40(a) because it provides reasonable assurance that the health and safety of the public will not be endangered.
[3.3 VARIATIONS FROM TSTF-566 The licensee described variations from TSTF-566 in Section 2.2 of the LAR. The licensee provided justification for the proposed variations and exceptions. The staff reviewed the justifications and concludes the variations are [not] acceptable because.
The [Name of facilitys] TSs utilize different [numbering][and][titles] than the Standard Technical Specifications on which TSTF-566 was based. The NRC staff agrees these differences are editorial and do not affect the applicability of TSTF-566 to the proposed LAR.]
4.0 STATE CONSULTATION
{This section is to be prepared by the plant project manager.}
In accordance with the Commissions regulations, the [Name of State] State official was notified of the proposed issuance of the amendment(s) on [date]. The State official had [no]
comments. [If comments were provided, they should be addressed here.]
5.0 ENVIRONMENTAL CONSIDERATION
{This section is to be prepared by the plant project manager in accordance with current procedures.}
6.0 CONCLUSION
{This section is to be prepared by the plant project manager.}
The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) there is reasonable assurance that such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment(s) will not be inimical to the common defense and security or to the health and safety of the public.
7.0 REFERENCES
{Optional section to be prepared by the PM and primary reviewers. If document is publicly available, the ADAMS Accession No. should be listed.}
{NOTE: These are the principal contributors for the model SE of the traveler. Replace these names with those who prepared the plant-specific SE.}
Principal Contributors: C. Tilton, NRR/DSS M. Razzaque, NRR/DSS Date: