TSTF-19-01, TSTF Comments on Draft Safety Evaluations for Traveler TSTF-566, Revision 0, Revise Actions for Inoperable RHR Shutdown Cooling Subsystems
| ML19017A269 | |
| Person / Time | |
|---|---|
| Site: | Technical Specifications Task Force, 99902042 |
| Issue date: | 01/17/2019 |
| From: | Gullott D, Joyce R, Miksa J, Sparkman W, Vaughn J AP1000 Owners Group (APOG), BWR Owners Group, Babcock & Wilcox, Combustion Engineering, PWR Owners Group, Technical Specifications Task Force, Westinghouse |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| TSTF-19-01 | |
| Download: ML19017A269 (20) | |
Text
TECHNICAL SPECIFICATIONS TASK FORCE TSTF A JOINT OWNERS GROUP ACTIVITY January 17, 2019 TSTF-19-01 PROJ0753 Attn: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
TSTF Comments on Draft Safety Evaluations for Traveler TSTF-566, Revision 0, "Revise Actions for Inoperable RHR Shutdown Cooling Subsystems"
REFERENCE:
Letter Victor Cusumano (NRC) to the TSTF, "Draft Safety Evaluations of Technical Specifications Task Force TSTF-566, Revision 0, 'Revise Actions for Inoperable RHR Shutdown Cooling Subsystems'," dated December 20, 2018 (ADAMS Accession No. ML18242A176).
On January 19, 2018, the TSTF submitted traveler TSTF-566, Revision 0, "Revise Actions for Inoperable RHR Shutdown Cooling Subsystems," to the Nuclear Regulatory Commission (NRC) for review (Agencywide Documents Access and Management System (ADAMS) Accession No. ML18019B187). In the referenced letter, the NRC provided the draft Safety Evaluations for TSTF-566 for comment.
Attachment 1 contains a summary table providing the TSTF's comments on the draft Safety Evaluations. Attachment 2 contains a mark-up reflecting the TSTF's comments.
Should you have any questions, please do not hesitate to contact us.
James P. Miksa (PWROG/CE) Ryan M. Joyce (BWROG)
David M. Gullott (PWROG/W) Jordan L. Vaughan (PWROG/B&W)
Wesley Sparkman (APOG) 11921 Rockville Pike, Suite 100, Rockville, MD 20852 Phone: 301-984-4400, Fax: 301-984-7600 Administration by EXCEL Services Corporation
TSTF-19-01 January 17, 2019 Page 2 TSTF Comments on the TSTF-566 Draft Safety Evaluations TSTF Markup of Draft Safety Evaluations cc: Michelle Honcharik, Technical Specifications Branch, NRC Victor Cusumano, Technical Specifications Branch, NRC
Attachment 1 TSTF Comments on the TSTF-566 Draft Safety Evaluations Comments on the TSTF-566 Traveler Draft Safety Evaluation Page(s) Line(s)1 Comment 1 37 Recommend that the RHR system description be revised to be consistent 2 1-6 with the traveler, which was worded to encompass differences in the Boiling Water Reactor design.
7 28-43 TSTF-566 includes changes to the NUREG-1433 TS 3.4.8, 3.4.9, 3.9.8, and 3.9.9 Bases and the NUREG-1434 TS 3.4.9, 3.4.10, 3.9.8, and 3.9.9 Bases justifying the use of an inoperable but functional RHR SDC subsystem as an alternate method of removing decay heat (see TSTF-566 justification, Section 3.3, "Bases Changes.") These changes are not discussed in Section 3.3, "Consideration of Changes to the Standard Technical Specification Bases," which only addresses Bases changes related to the Technical Specification changes made in TSTF-566.
Recommend the Safety Evaluation be revised to address these changes.
Comments on the TSTF-566 Draft Model Safety Evaluation Page(s) Line(s)1 Comment 2 6-7 The model Safety Evaluation contains a note that states that the technical 17-25 reviewers and/or project manager should verify that the RHR shutdown cooling system description is applicable to the plant and revise the section if necessary. However, the model application does not require the licensee to describe the plant's RHR shutdown cooling system and the applicability of the proposed change is not dependent on the RHR shutdown cooling system design details. To avoid unnecessary requests for additional information regarding the RHR shutdown cooling system design, we recommend deleting the note and replacing the system description with the generic system description in TSTF-566.
1 Line numbers correspond to the attached proposed revision, not to the documents provided by the NRC.
Page 3
Attachment 2 TSTF Markup of Draft Safety Evaluations
1 DRAFT SAFETY EVALUATION 2 BY THE OFFICE OF NUCLEAR REACTOR REGULATION 3 TECHNICAL SPECIFICATIONS TASK FORCE TRAVELER 4 TSTF-566, REVISION 0 5 REVISE ACTIONS FOR INOPERABLE RHR SHUTDOWN COOLING SUBSYSTEM 6 USING THE CONSOLIDATED LINE ITEM IMPROVEMENT PROCESS 7 (EPID L-2018-PMP-0001) 8 9
10
1.0 INTRODUCTION
11 12 By letter dated January 19, 2018 (Agencywide Documents Access and Management System 13 (ADAMS) Accession No. ML18019B187), the Technical Specifications Task Force (TSTF) 14 submitted traveler TSTF-566, Revision 0, Revise Actions for Inoperable RHR [Residual Heat 15 Removal] Shutdown Cooling Subsystems. Traveler TSTF-566, Revision 0, proposed changes 16 to the Standard Technical Specifications (STS) for boiling-water reactor (BWR) designs.1 These 17 changes would be incorporated into future revisions of NUREG-1433 and NUREG-1434.
18 19 The proposed changes would revise TS actions for inoperable RHR shutdown cooling 20 subsystems in the RHR shutdown cooling system limiting conditions for operation (LCOs).
21 This STS change will be made available to licensees through the consolidated line item 22 improvement process.
23 24
2.0 REGULATORY EVALUATION
25 26
2.1 DESCRIPTION
OF THE RESIDUAL HEAT REMOVAL SHUTDOWN 27 COOLING SYSTEM 28 29 Irradiated fuel in the shutdown reactor core generates heat during the decay of fission products 30 and increases the temperature of the reactor coolant. This decay heat must be removed to 31 reduce the temperature of the reactor coolant to less than or equal to 200 degrees 32 Fahrenheit (°F). This decay heat is removed by the RHR shutdown cooling system in 33 preparation for performing refueling or maintenance operations, or for keeping the reactor in the 34 hot shutdown condition or cold shutdown condition.
35 36 Typical BWR designs consist of two redundant, manually controlled shutdown cooling 37 subsystems of the RHR system to provide decay heat removal. Each loop consists of one or 1 U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General Electric Plants, BWR/4, 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 Plants, BWR/6, NUREG-1434, Volume 1, Specifications, and Volume 2, Bases, Revision 4.0, April 2012 (ADAMS Accession Nos. ML12104A195 and ML12104A196, respectively).
Enclosure 1
1 two motor-driven pumps, a heat exchanger, and associated piping and valves. The RHR heat 2 exchangers transfer heat to the RHR Service Water System. Some piping and heat exchangers 3 that are passive components may be common to both subsystems. Both loops have a common 4 suction from the same recirculation loop. Each pump discharges the reactor coolant, after 5 circulation through the respective heat exchanger, to the reactor via the associated recirculation 6 loop.
7 8 Technical Specification 3.4.8 for NUREG-1433 and TS 3.4.9 for NUREG-1434, Residual Heat 9 Removal (RHR) Shutdown Cooling System - Hot Shutdown, are applicable in Mode 3 with 10 reactor steam dome pressure lower than the RHR cut-in permissive pressure. Technical 11 Specification 3.4.9 for NUREG-1433 and TS 3.4.10 for NUREG-1434, Residual Heat Removal 12 (RHR) Shutdown Cooling System - Cold Shutdown, are applicable in Mode 4. They all require 13 two operable RHR shutdown cooling subsystems and, with no recirculation pump in operation, 14 at least one RHR shutdown cooling subsystem in operation.
15 16
2.2 PROPOSED CHANGE
S TO THE STANDARD TECHNICAL 17 SPECIFICATIONS 18 19 The proposed changes would revise TS 3.4.8 for NUREG-1433 and TS 3.4.9 for NUREG-1434, 20 Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown, and TS 3.4.9 for 21 NUREG-1433 and TS 3.4.10 for NUREG-1434, Residual Heat Removal (RHR) Shutdown 22 Cooling System - Cold Shutdown. The proposed changes are described below.
23 24 2.2.1 Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling 25 System - Hot Shutdown 26 27 Required actions for one or two RHR shutdown cooling subsystems inoperable (Condition A) of 28 TS 3.4.8 for NUREG-1433 and TS 3.4.9 for NUREG-1434, Residual Heat Removal (RHR) 29 Shutdown Cooling System - Hot Shutdown, require the operators to initiate action to restore 30 RHR shutdown cooling subsystem(s) to operable status (Required Action A.1) immediately, 31 verify an alternate method of decay heat removal is available for each inoperable RHR 32 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 33 Action A.3) within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
34 35 Traveler TSTF-566, Revision 0, proposed to move Required Action A.1 to new Condition B (as 36 Required Action B.1) and delete Required Action A.3. It also proposed to add a recurring 37 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 38 traveler renumbers current Required Action A.2 as A.1, since Required Actions A.1 and A.3 are 39 removed from Condition A.
40 41 Traveler TSTF-566, Revision 0, also proposed a new Condition B for when the required action 42 and associated CT of Condition A are not met. New Condition Bs Required Action B.1 is 43 moved from current Required Action A.1 and requires operators to initiate action to restore RHR 44 shutdown cooling subsystems(s) to operable status immediately.
45 46 Current Required Action A.2 was renumbered as A.1 since Required Actions A.1 and A.3 were 47 deleted. Current Condition B and its required actions were renamed C, C.1, C.2, and C.3, 48 respectively, since new Condition B was added. Conforming changes were also made to the 49 STS Bases.
50
1 2.2.2 Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling 2 System - Cold Shutdown 3
4 Required actions for one or two RHR shutdown cooling subsystems inoperable (Condition A) of 5 TS 3.4.9 for NUREG-1433 and TS 3.4.10 for NUREG-1434, Residual Heat Removal (RHR) 6 Shutdown Cooling System - Cold Shutdown, require the operators to verify an alternate 7 method of decay heat removal is available for each inoperable RHR shutdown cooling 8 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.
9 10 Traveler TSTF-566, Revision 0, proposed a new Condition B for when the required action and 11 associated CT of Condition A is not met, which has a required action (new Required Action B.1) 12 for operators to initiate action to restore RHR shutdown cooling subsystems(s) to operable 13 status immediately.
14 15 Current Condition B and its required actions were renamed C, C.1, and C.2, respectively, 16 since new Condition B was added. Conforming changes were also made to the STS Bases.
17 18 2.3 APPLICABLE REGULATORY REQUIREMENTS AND GUIDANCE 19 20 Section IV, The Commission Policy, of the Final Policy Statement on Technical Specifications 21 Improvements for Nuclear Power Reactors, published in the Federal Register on July 22, 1993 22 (58 FR 39132), states, in part:
23 24 The purpose of Technical Specifications is to impose those 25 conditions or limitations upon reactor operation necessary to 26 obviate the possibility of an abnormal situation or event giving rise 27 to an immediate threat to the public health and safety by 28 identifying those features that are of controlling importance to 29 safety and establishing on them certain conditions of operation 30 which cannot be changed without prior Commission approval.
31 32 [T]he Commission will also entertain requests to adopt portions 33 of the improved STS [(e.g., TSTF-566)], even if the licensee does 34 not adopt all STS improvements. The Commission encourages 35 all licensees who submit Technical Specification related submittals 36 based on this Policy Statement to emphasize human factors 37 principles.
38 39 In accordance with this Policy Statement, improved STS have 40 been developed and will be maintained for each NSSS [nuclear 41 steam supply system] owners group. The Commission 42 encourages licensees to use the improved STS as the basis for 43 plant-specific Technical Specifications. [I]t is the Commission 44 intent that the wording and Bases of the improved STS be used 45 to the extent practicable.
46 47 The Commission Policy concerning Bases is, in part:
48 49 Each LCO, Action, and Surveillance Requirement should have 50 supporting Bases. The Bases should at a minimum address the
1 following questions and cite references to appropriate licensing 2 documentation (e.g., FSAR, Topical Report) to support the Bases.
3 4 1. What is the justification for the Technical Specification, i.e.,
5 which Policy Statement criterion requires it to be in the Technical 6 Specifications?
7 8 2. What are the Bases for each LCO, i.e., why was it determined 9 to be the lowest functional capability or performance level for the 10 system or component in question necessary for safe operation of 11 the facility and, what are the reasons for the Applicability of the 12 LCO?
13 14 3. What are the Bases for each Action, i.e., why should this 15 remedial action be taken if the associated LCO cannot be met; 16 how does this Action relate to other Actions associated with the 17 LCO; and what justifies continued operation of the system or 18 component at the reduced state from the state specified in the 19 LCO for the allowed time period?
20 21 As described in the Commissions Final Policy Statement on Technical Specifications 22 Improvements for Nuclear Power Reactors, the NRC and industry task groups for new STS 23 recommended that improvements include greater emphasis on human factors principles in order 24 to add clarity and understanding to the text of the STS, and provide improvements to the Bases 25 of STS, which provides the purpose for each requirement in the specification. The improved 26 vendor-specific STS were developed and issued by the NRC in September 1992.
27 28 The regulation at Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36(b) 29 requires:
30 31 Each license authorizing operation of a utilization facility will 32 include technical specifications. The technical specifications will 33 be derived from the analyses and evaluation included in the safety 34 analysis report, and amendments thereto, submitted pursuant to 35 [10 CFR] 50.34 [Contents of applications; technical information].
36 The Commission may include such additional technical 37 specifications as the Commission finds appropriate.
38 39 Per regulation at 10 CFR 50.40, Common Standards:
40 41 In determining that [an] operating license will be issued to an 42 applicant, the Commission will be guided by the following 43 considerations:
44 45 (a) the processes to be performed, the operating procedures, 46 the facility and equipment, the use of the facility, and other 47 technical specifications, or the proposals, in regard to any of the 48 foregoing collectively provide reasonable assurance that the 49 applicant will comply with the regulations in this chapter, including 50 the regulations in part 20 of this chapter, and that the health and 51 safety of the public will not be endangered.
1 2 The NRC staffs guidance for the review of TSs is in Chapter 16.0, Technical Specifications, of 3 NUREG-0800, Revision 3, Standard Review Plan for the Review of Safety Analysis Reports for 4 Nuclear Power Plants, LWR [Light-Water Reactor] Edition (SRP), March 2010 (ADAMS 5 Accession No. ML100351425). As described therein, as part of the regulatory standardization 6 effort, the NRC staff has prepared STS for each of the LWR nuclear designs. Accordingly, the 7 NRC staffs review includes consideration of whether the proposed changes are consistent with 8 the applicable reference STS (i.e., the current STS), as modified by NRC-approved travelers. In 9 addition, the guidance states that comparing the change to previous STS can help clarify the TS 10 intent.
11 12
3.0 TECHNICAL EVALUATION
13 14
3.1 PROPOSED CHANGE
S TO RESIDUAL HEAT REMOVAL (RHR) 15 SHUTDOWN COOLING SYSTEM - HOT SHUTDOWN 16 17 In traveler TSTF-566, Revision 0, the TSTF proposed to modify TS 3.4.8 for NUREG-1433 and 18 TS 3.4.9 for NUREG-1434, Residual Heat Removal (RHR) Shutdown Cooling System - Hot 19 Shutdown. The technical evaluation of each change follows.
20 21 3.1.1 Evaluation of Changes to Condition A 22 23 Traveler TSTF-566, Revision 0, proposed to add a recurring CT to current Required Action A.2 24 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 25 alternate method of decay heat removal is available for each inoperable RHR shutdown cooling 26 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 27 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 28 assurance of continued heat removal capability.
29 30 Traveler TSTF-566, Revision 0, also proposed to delete current Required Action A.3 which 31 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 32 subsystems are inoperable. Current Required Action A.3 requires operators to reduce the 33 reactor coolant system temperature to the point where Mode 4 is entered due to the potentially 34 reduced reliability of the alternate methods of decay heat removal. However, if there is no 35 operable RHR shutdown cooling subsystem and the plant is in a period of high decay heat load, 36 it may not be possible to reduce the reactor coolant system temperature to the Mode 4 entry 37 condition (typically less than 200 °F) within the CT. In addition, in a typical BWR design, the 38 RHR shutdown cooling system has a heat rejection capability many times greater than alternate 39 methods available. Therefore, for periods in which there is high decay heat load, the BWR 40 design does not include any system which can satisfy Required Action A.3. The NRC staff finds 41 the deletion of current Required Action A.3 is acceptable because, at below the RHR cut-in 42 permissive pressure, the remaining required action will continue to transfer fission product 43 decay heat and other residual heat from the reactor core at a rate such that specified 44 acceptable fuel design limits and the design conditions of the reactor coolant pressure boundary 45 are not exceeded.
46 47 Current Required Action A.2 is renumbered as A.1, since Required Actions A.1 and A.3 are 48 removed from Condition A. The NRC staff finds this change is acceptable since it provides the 49 correct number sequence.
50
1 3.1.2 Evaluation of New Condition B 2
3 Traveler TSTF-566, Revision 0, proposed a new Condition B for when required action and 4 associated CT of Condition A is not met. New Condition Bs required action, B.1, is moved from 5 current Required Action A.1 and requires operators to initiate action to restore RHR shutdown 6 cooling subsystems(s) to operable status immediately. The NRC staff finds that relocating the 7 required action from A.1 to new Required Action B.1 is acceptable because other ways of 8 removing decay heat are available, such as natural circulation, the spent fuel pool cooling 9 system, the reactor water cleanup system, and an inoperable but functional RHR shutdown 10 cooling subsystem.
11 12 If an alternate method cannot be established (Condition A), new Condition B requires the 13 licensee to immediately initiate action to restore the inoperable RHR shutdown cooling 14 subsystem(s) to operable status. The CT immediately is defined in Section 1.3 of the TSs as, 15 the Required Action should be pursued without delay and in a controlled manner. New 16 Required Action B.1 continues to apply until the inoperable RHR shutdown cooling subsystems 17 are restored to operable status, an alternate decay heat removal method is established, or the 18 specification is exited.
19 20 The NRC staff finds this change is acceptable because new Condition B with its Required 21 Action B.1 provide an appropriate action for when an alternate method cannot be established 22 within the CT. In addition, new Required Action B.1 will restore redundant decay heat removal 23 paths and the immediate CT reflects the importance of maintaining the availability of two paths 24 for heat removal.
25 26 3.1.3 Evaluation of Changes to Existing Condition B 27 28 Current Required Action A.2 was renumbered as A.1, since Required Actions A.1 and A.3 were 29 deleted. Current Condition B and its required actions were renamed C, C.1, C.2, and C.3, 30 respectively, since new Condition B was added. The NRC staff finds this change is acceptable 31 since it provides the correct number sequence.
32 33 3.1.4 Conclusion of Proposed Changes to Residual Heat Removal (RHR) 34 Shutdown Cooling System - Hot Shutdown 35 36 The NRC staff concludes the proposed changes are acceptable since the remedial actions 37 provide reasonable assurance that the health and safety of the public will not be endangered.
38 39
3.2 PROPOSED CHANGE
S TO RESIDUAL HEAT REMOVAL (RHR) 40 SHUTDOWN COOLING SYSTEM - COLD SHUTDOWN 41 42 In traveler TSTF-566, Revision 0, the TSTF proposed to modify TS 3.4.9 for NUREG-1433 and 43 TS 3.4.10 for NUREG-1434, Residual Heat Removal (RHR) Shutdown Cooling System - Cold 44 Shutdown. The technical evaluation of each change follows.
45 46 3.2.1 Evaluation of New Condition B 47 48 Traveler TSTF-566, Revision 0, proposed a new Condition B for when required action and 49 associated CT of Condition A is not met which has a required action (new Required Action B.1) 50 for operators to initiate action to restore RHR shutdown cooling subsystems(s) to operable 51 status immediately.
1 2 If an alternate method cannot be established (Condition A), new Condition B requires the 3 licensee to immediately initiate action to restore the inoperable RHR shutdown cooling 4 subsystem(s) to operable status. The CT immediately is defined in Section 1.3 of the TSs as, 5 the Required Action should be pursued without delay and in a controlled manner. New 6 Required Action B.1 continues to apply until the inoperable RHR shutdown cooling subsystems 7 are restored to operable status, an alternate decay heat removal method is established, or the 8 specification is exited.
9 10 The NRC staff finds this change is acceptable because new Condition B with its Required 11 Action B.1 provides an appropriate terminal action for when an alternate method cannot be 12 established within the CT. In addition, new Required Action B.1 will restore redundant decay 13 heat removal paths and the immediate CT reflects the importance of maintaining the availability 14 of two paths for heat removal.
15 16 3.2.2 Evaluation of Changes to Existing Condition B 17 18 Current Condition B and its required actions were renamed C, C.1, and C.2, respectively, 19 since new Condition B was added. The NRC staff finds this change is acceptable since it 20 provides the correct number sequence.
21 22 3.2.3 Conclusion of Proposed Changes to Residual Heat Removal (RHR) 23 Shutdown Cooling System - Cold Shutdown 24 25 The NRC staff concludes the proposed changes are acceptable since the remedial actions 26 provide reasonable assurance that the health and safety of the public will not be endangered.
27 28 3.3 CONSIDERATION OF CHANGES TO THE STANDARD TECHNICAL 29 SPECIFICATION BASES 30 31 Traveler TSTF-566, Revision 0, proposed changes to the STS Bases that conformed to the TS 32 changes made. Specifically moving Action A.1 and renumbering it as B.1, and renumbering the 33 other actions accordingly. The proposed changes to the STS Bases explain that if the required 34 alternate method(s) of decay heat removal cannot be verified within one hour as required by 35 Action A.1, immediate action must be taken to restore the inoperable RHR shutdown cooling 36 subsystem(s). It continues by stating that the new required action will restore redundant decay 37 heat removal paths and its immediate CT reflects the importance of maintaining the availability 38 of two paths for heat removal. The NRC staff finds the Bases for each Action acceptable 39 because they are editorial in nature (movement of existing wording and renumbering to match 40 new TS numbering) and continue to provide the reasons or bases for the specifications, as 41 described in 10 CFR 50.36(a). The Bases for addition of a recurring CT for Action A.2 of once 42 per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> thereafter, is acceptable based on engineering judgement because the 43 continuous verification will provide assurance of continued heat removal capability.
44 45
4.0 CONCLUSION
46 47 The NRC staff reviewed traveler TSTF-566, Revision 0, which proposed changes to 48 NUREG-1433 and NUREG-1434. The NRC staff determined that the proposed changes to the 49 STS continue to meet the Commissions Final Policy Statement on Technical Specifications 50 Improvements for Nuclear Power Reactors and 10 CFR 50.36. Additionally, the changes to the 51 STS were reviewed and found to be technically clear and consistent with customary terminology
1 and format in accordance with SRP Chapter 16.0. The NRC staff reviewed the proposed 2 changes to the action statements and concludes that the changes continue to provide 3 reasonable assurance and protection of the health and safety of the public. Therefore, the NRC 4 staff concludes that the proposed TS changes are acceptable.
5 6 Principal Contributors: C. Tilton, NRR/DSS 7 M. Razzaque, NRR/DSS 8
9 Date:
1 General Directions: This Model safety evaluation (SE) provides the format and content to be 2 used when preparing the plant-specific SE of a license amendment request to adopt TSTF-566, 3 Revision 0. The bolded bracketed information shows text that should be filled in for the specific 4 amendment; individual licensees would furnish site-specific nomenclature or values for these 5 bracketed items. The italicized wording provides guidance on what should be included in each 6 section and should not be included in the SE.
7 8 DRAFT SAFETY EVALUATION 9 BY THE OFFICE OF NUCLEAR REACTOR REGULATION 10 TECHNICAL SPECIFICATIONS TASK FORCE TRAVELER 11 TSTF-566, REVISION 0 12 REVISE ACTIONS FOR INOPERABLE RHR SHUTDOWN COOLING SUBSYSTEM 13 USING THE CONSOLIDATED LINE ITEM IMPROVEMENT PROCESS 14 15 16
1.0 INTRODUCTION
17 18 By application dated [enter date], (Agencywide Documents Access and Management System 19 (ADAMS) Accession No. [MLXXXXXXXXX]), [as supplemented by letters dated [enter 20 date(s))), [name of licensee] (the licensee) submitted a license amendment request (LAR) for 21 [name of facility (abbreviated name), applicable units]. The amendment would revise 22 technical specification (TS) actions for inoperable residual heat removal (RHR) shutdown 23 cooling subsystems in the RHR shutdown cooling system limiting conditions for operation 24 (LCOs).
25 26 The proposed changes are based on Technical Specifications Task Force (TSTF) traveler 27 TSTF-566, Revision 0, Revise Actions for Inoperable RHR Shutdown Cooling Subsystems, 28 dated January 19, 2018 (ADAMS Accession No. ML18019B187). The U.S. Nuclear Regulatory 29 Commission (NRC or the Commission) issued a final safety evaluation (SE) approving 30 TSTF-566, Revision 0, on [enter date] (ADAMS Accession No. [MLXXXXXXXXX]).
31 32 [The licensee has proposed variations from the TS changes described in TSTF-566, 33 Revision 0. The variations are described in Section [2.2.1] of this SE and evaluated in 34 Section [3.3)). OR [The licensee is not proposing any variations from the TS changes 35 described in TSTF-566 or the applicable parts of the NRC staffs SE of TSTF-566.))
36 37 [The supplemental letters dated [enter date(s)], provided additional information that 38 clarified the application, did not expand the scope of the application as originally 39 noticed, and did not change the NRC staffs original proposed no significant hazards 40 consideration determination as published in the Federal Register on [enter date] (cite FR 41 reference).]
42 Enclosure 2
1
2.0 REGULATORY EVALUATION
2 3
2.1 DESCRIPTION
OF RESIDUAL HEAT REMOVAL SHUTDOWN 4 COOLING SYSTEM 5
6 {NOTE: Technical reviewers and/or the project manager should verify that the RHR shutdown 7 cooling system description is applicable to this plant and revise this section if necessary.}
8 9 Irradiated fuel in the shutdown reactor core generates heat during the decay of fission products 10 and increases the temperature of the reactor coolant. This decay heat must be removed to 11 reduce the temperature of the reactor coolant to less than or equal to 200 degrees Fahrenheit 12 (°F). This decay heat is removed by the RHR shutdown cooling system in preparation for 13 performing refueling or maintenance operations, or for keeping the reactor in the hot shutdown 14 condition or cold shutdown condition.
15 16 The two redundant, manually controlled shutdown cooling subsystems of the RHR system 17 provide decay heat removal. Each of the two shutdown cooling subsystems of the RHR System 18 can provide the required decay heat removal. Each RHR shutdown cooling subsystem consists 19 of one or two motor driven pumps, a heat exchanger, and associated piping and valves. The 20 RHR heat exchangers transfer heat to the RHR Service Water System. Some piping and heat 21 exchangers that are passive components may be common to both subsystems. Each loop 22 consists of two motor-driven pumps, a heat exchanger, and associated piping and valves. Both 23 loops have a common suction from the same recirculation loop. Each pump discharges the 24 reactor coolant, after circulation through the respective heat exchanger, to the reactor via the 25 associated recirculation loop.
26 27 Technical Specification [3.4.8], Residual Heat Removal (RHR) Shutdown Cooling System -
28 Hot Shutdown, is applicable on Mode 3 [with reactor steam dome pressure lower than the 29 RHR cut-in permissive] pressure. Technical Specification [3.4.9], Residual Heat Removal 30 (RHR) Shutdown Cooling System - Cold Shutdown, is applicable in Mode 4. They both require 31 two operable RHR shutdown cooling subsystems and, with no recirculation pump in operation, 32 at least one RHR shutdown cooling subsystem in operation.
33 34
2.2 PROPOSED CHANGE
S TO THE TECHNICAL SPECIFICATIONS 35 36 The licensee proposed to revise TS actions for inoperable RHR shutdown cooling subsystems 37 in the RHR shutdown cooling system LCOs, consistent with TSTF-566, Revision 0.
38 39 The proposed changes would revise TS [3.4.8], Residual Heat Removal (RHR) Shutdown 40 Cooling System - Hot Shutdown, and [3.4.9], Residual Heat Removal (RHR) Shutdown 41 Cooling System - Cold Shutdown, for [Name of facility]. The proposed changes are 42 described below.
43 44 2.2.1 Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling 45 System - Hot Shutdown 46 47 Required actions for one or two RHR shutdown cooling subsystems inoperable (Condition A) of 48 [Name of facility] TS [3.4.8], Residual Heat Removal (RHR) Shutdown Cooling System - Hot 49 Shutdown, require the operators to initiate action to restore RHR shutdown cooling 50 subsystem(s) to operable status (Required Action A.1) immediately, verify an alternate method
1 of decay heat removal is available for each inoperable RHR shutdown cooling subsystem 2 (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 />.
3 4 The licensee proposed to move Required Action A.1 to new Condition B (as Required 5 Action B.1) and delete Required Action A.3. The LAR also proposed to add a recurring 6 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 7 proposed changes also renumber current Required Action A.2 as A.1 since Required 8 Actions A.1 and A.3 are removed from Condition A.
9 10 The licensee also proposed a new Condition B for when the required action and associated CT 11 of Condition A are not met. New Condition Bs Required Action B.1 is moved from current 12 Required Action A.1 and requires operators to initiate action to restore RHR shutdown cooling 13 subsystems(s) to operable status immediately.
14 15 Current Required Action A.2 was renumbered as A.1, since Required Actions A.1 and A.3 were 16 deleted. Current Condition B and its required actions were renamed C, C.1, C.2, and C.3, 17 respectively, since new Condition B was added. .
18 19 2.2.2 Proposed Changes to Residual Heat Removal (RHR) Shutdown Cooling 20 System - Cold Shutdown 21 22 Required actions for one or two RHR shutdown cooling subsystems inoperable (Condition A) of 23 TS [3.4.9], Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown, 24 require the operators to verify an alternate method of decay heat removal is available for each 25 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 26 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> thereafter.
27 28 The licensee proposed a new Condition B for when the required action and associated CT of 29 Condition A are not met which has a required action (new Required Action B.1) for operators to 30 initiate action to restore RHR shutdown cooling subsystems(s) to operable status immediately.
31 32 Current Condition B and its required actions were renamed C, C.1, and C.2, respectively, 33 since new Condition B was added. .
34 35 2.2.1 Variations from TSTF-566 36 37 {NOTE: Technical reviewers and/or the project manager are to assess the adequacy of any 38 variations from the approved traveler and document their acceptability. Choose the applicable 39 paragraphs based on information provided in the LAR.}
40 41 [The licensee is proposing the following variations from the TS changes described in 42 TSTF-566 or the applicable parts of the NRC staffs SE of TSTF-566. [Describe the 43 variations and why TSTF-566 is still applicable.] These variations do not affect the 44 applicability of TSTF-566 or the NRC staff's SE to the proposed LAR.]
45 46 [The [PLANT] TSs utilize different [numbering][and][titles] than the Standard Technical 47 Specifications (STS)on which TSTF-566 was based. Specifically, [describe differences 48 between the plant-specific TS numbering and/or titles and the TSTF-566 numbering 49 and/or titles.] These differences are editorial and do not affect the applicability of 50 TSTF-566 to the proposed LAR.]
51
1 [The [PLANT] design is different than the model plant assumed in the Standard Technical 2 Specifications, but the TSTF-566 justification and the NRC staff's SE are still applicable.
3 [Describe differences and why TSTF-566 is still applicable.))
4 5 2.3 APPLICABLE REGULATORY REQUIREMENTS AND GUIDANCE 6
7 Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36(a)(1) requires each 8 applicant for a license authorizing operation of a utilization facility to include in the application 9 proposed TSs.
10 11 The regulation at 10 CFR 50.36(b) requires:
12 13 Each license authorizing operation of a utilization facility will include 14 technical specifications. The technical specifications will be derived from the 15 analyses and evaluation included in the safety analysis report, and amendments 16 thereto, submitted pursuant to [10 CFR] 50.34 [Contents of applications; 17 technical information]. The Commission may include such additional technical 18 specifications as the Commission finds appropriate.
19 20 The regulation at 10 CFR 50.40(a) in part states that the technical specifications shall provide 21 reasonable assurance that the health and safety of the public will not be endangered.
22 23 The regulation at 10 CFR 50.36(a)(1) states, in part: A summary statement of the bases or 24 reasons for such specifications, other than those covering administrative controls, shall also be 25 included in the application, but shall not become part of the technical specifications.
26 27 The NRC staffs guidance for the review of TSs is in Chapter 16.0, Technical Specifications, of 28 NUREG-0800, Revision 3, Standard Review Plan for the Review of Safety Analysis Reports for 29 Nuclear Power Plants, LWR [Light-Water Reactor] Edition (SRP), March 2010 (ADAMS 30 Accession No. ML100351425). As described therein, as part of the regulatory standardization 31 effort, the NRC staff has prepared Standard Technical Specifications (STS) for each of the LWR 32 nuclear designs. Accordingly, the NRC staffs review includes consideration of whether the 33 proposed changes are consistent with the applicable reference STS (i.e., the current STS), as 34 modified by NRC-approved travelers.
35 36 {NOTE: Choose applicable STS}
37 [U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General 38 Electric BWR/4 Plants, NUREG-1433, Volume 1, Specifications, and Volume 2, 39 Bases, Revision 4.0, April 2012 (ADAMS Accession Nos. ML12104A192 and 40 ML12104A193, respectively).
41 42 U.S. Nuclear Regulatory Commission, Standard Technical Specifications, General 43 Electric BWR/6 Plants, NUREG-1434, Volume 1, Specifications, and Volume 2, 44 Bases, Revision 4.0, April 2012 (ADAMS Accession Nos. ML12104A195 and 45 ML12104A196, respectively).]
46
1
3.0 TECHNICAL EVALUATION
2 3
3.1 PROPOSED CHANGE
S TO RESIDUAL HEAT REMOVAL (RHR) SHUTDOWN 4 COOLING SYSTEM - HOT SHUTDOWN 5
6 The licensee proposed to modify TS [3.4.8], Residual Heat Removal (RHR) Shutdown Cooling 7 System - Hot Shutdown. The technical evaluation of each change follows.
8 9 3.1.1 Evaluation of Changes to Condition A 10 11 The licensee proposed to add a recurring CT to current Required Action A.2 of once per 12 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 13 of decay heat removal is available for each inoperable RHR shutdown cooling subsystem within 14 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 15 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 16 continued heat removal capability.
17 18 The licensee also proposed to delete current Required Action A.3, which requires the plant to be 19 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.
20 Current Required Action A.3 requires operators to reduce the reactor coolant system 21 temperature to the point where Mode 4 is entered, due to the potentially reduced reliability of the 22 alternate methods of decay heat removal. However, if there is no operable RHR shutdown 23 cooling subsystem and the plant is in a period of high decay heat load, it may not be possible to 24 reduce the reactor coolant system temperature to the Mode 4 entry condition (typically less than 25 200 °F) within the CT. In addition, in a typical BWR design, the RHR shutdown cooling system 26 has a heat rejection capability many times greater than alternate methods available. Therefore, 27 for periods in which there is high decay heat load, the BWR design does not include any system 28 which can satisfy Required Action A.3. The NRC staff finds the deletion of current Required 29 Action A.3 is acceptable because, at below the RHR cut in permissive pressure, the remaining 30 required action will continue to transfer fission product decay heat and other residual heat from 31 the reactor core at a rate such that specified acceptable fuel design limits and the design 32 conditions of the reactor coolant pressure boundary are not exceeded.
33 34 Current Required Action A.2 is renumbered as A.1, since Required Actions A.1 and A.3 are 35 removed from Condition A. The NRC staff finds this change is acceptable since it provides the 36 correct number sequence.
37 38 3.1.2 Evaluation of New Condition B 39 40 The licensee proposed a new Condition B for when required action and associated CT of 41 Condition A is not met. New Condition Bs required action, B.1, is moved from current Required 42 Action A.1 and requires operators to initiate action to restore RHR shutdown cooling 43 subsystems(s) to operable status immediately. The NRC staff finds that relocating the required 44 action from A.1 to new Required Action B.1 is acceptable because other ways of removing 45 decay heat are available, such as natural circulation, the spent fuel pool cooling system, the 46 reactor water cleanup system and an inoperable, but functional, RHR shutdown cooling 47 subsystem.
48 49 If an alternate method cannot be established (Condition A), new Condition B requires the 50 licensee to immediately initiate action to restore the inoperable RHR shutdown cooling 51 subsystem(s) to operable status. The CT immediately is defined in Section 1.3 of the [Name
1 of facility]s TSs as, the Required Action should be pursued without delay and in a controlled 2 manner. New Required Action B.1 continues to apply until the inoperable RHR shutdown 3 cooling subsystems are restored to operable status, an alternate decay heat removal method is 4 established, or the specification is exited.
5 6 The NRC staff finds this change is acceptable because new Condition B, with its Required 7 Action B.1, provides an appropriate terminal action for when an alternate method cannot be 8 established within the CT. In addition, new Required Action B.1 will restore redundant decay 9 heat removal paths and the immediate CT reflects the importance of maintaining the availability 10 of two paths for heat removal.
11 12 3.1.3 Evaluation of Changes to Existing Condition B 13 14 Current Required Action A.2 was renumbered as A.1, since Required Actions A.1 and A.3 were 15 deleted. Current Condition B and its required actions were renamed C, C.1, C.2, and C.3, 16 respectively, since new Condition B was added. The NRC staff finds this change is acceptable 17 since it provides the correct number sequence.
18 19 3.1.4 Conclusion of Proposed Changes to Residual Heat Removal (RHR) 20 Shutdown Cooling System - Hot Shutdown 21 22 The NRC staff concludes the proposed changes are acceptable since the TS continue to meet 23 the requirements of 10 CFR 50.40(a) because it provides reasonable assurance that the health 24 and safety of the public will not be endangered.
25 26
3.2 PROPOSED CHANGE
S TO RESIDUAL HEAT REMOVAL (RHR) 27 SHUTDOWN COOLING SYSTEM - COLD SHUTDOWN 28 29 The licensee proposed to modify TS [3.4.9], Residual Heat Removal (RHR) Shutdown Cooling 30 System - Cold Shutdown. The technical evaluation of each change follows.
31 32 3.2.1 Evaluation of New Condition B 33 34 The licensee proposed a new Condition B for when the required action and associated CT of 35 Condition A is not met which has a required action (new Required Action B.1) for operators to 36 initiate action to restore RHR shutdown cooling subsystems(s) to operable status immediately.
37 38 If an alternate method cannot be established (Condition A), new Condition B requires the 39 licensee to immediately initiate action to restore the inoperable RHR shutdown cooling 40 subsystem(s) to operable status. The CT immediately is defined in Section 1.3 of the TSs as, 41 the Required Action should be pursued without delay and in a controlled manner. New 42 Required Action B.1 continues to apply until the inoperable RHR shutdown cooling subsystems 43 are restored to operable status, an alternate decay heat removal method is established, or the 44 specification is exited.
45 46 The NRC staff finds this change is acceptable because new Condition B with its Required 47 Action B.1 provide an appropriate terminal action for when an alternate method cannot be 48 established within the CT. In addition, new Required Action B.1 will restore redundant decay 49 heat removal paths and the immediate CT reflects the importance of maintaining the availability 50 of two paths for heat removal.
51
1 3.2.2 Evaluation of Changes to Existing Condition B 2
3 Current Condition B and its required actions were renamed C, C.1, and C.2, respectively, 4 since new Condition B was added. The NRC staff finds this change is acceptable since it 5 provides the correct number sequence.
6 7 3.2.3 Conclusion of Proposed Changes to Residual Heat Removal (RHR) 8 Shutdown Cooling System - Cold Shutdown 9
10 The NRC staff concludes the proposed changes are acceptable since the TS continues to meet 11 the requirements of 10 CFR 50.40(a) because it provides reasonable assurance that the health 12 and safety of the public will not be endangered.
13 14 [3.3 VARIATIONS FROM TSTF-566 15 16 The licensee described variations from TSTF-566 in Section 2.2 of the LAR. The licensee 17 provided justification for the proposed variations and exceptions. The staff reviewed the 18 justifications and concluded the variations are [not] acceptable because.
19 20 The [Name of facilitys] TSs utilize different [numbering][and][titles] than the Standard 21 Technical Specifications on which TSTF-566 was based. The NRC staff agrees these 22 differences are editorial and do not affect the applicability of TSTF-566 to the proposed 23 LAR.]
24 25
4.0 STATE CONSULTATION
26 27 {This section is to be prepared by the plant project manager.}
28 29 In accordance with the Commissions regulations, the [Name of State] State official was notified 30 of the proposed issuance of the amendment(s) on [date]. The State official had [no]
31 comments. [If comments were provided, they should be addressed here.]
32 33
5.0 ENVIRONMENTAL CONSIDERATION
34 35 {This section is to be prepared by the plant project manager in accordance with current 36 procedures.}
37 38
6.0 CONCLUSION
39 40 {This section is to be prepared by the plant project manager.}
41 42 The Commission has concluded, based on the considerations discussed above, that: (1) there 43 is reasonable assurance that the health and safety of the public will not be endangered by 44 operation in the proposed manner, (2) there is reasonable assurance that such activities will be 45 conducted in compliance with the Commissions regulations, and (3) the issuance of the 46 amendment(s) will not be inimical to the common defense and security or to the health and 47 safety of the public.
48
1
7.0 REFERENCES
2 3 {Optional section to be prepared by the PM and primary reviewers. If document is publicly 4 available, the ADAMS Accession No. should be listed.}
5 6 {NOTE: These are the principal contributors for the model SE of the traveler. Replace these 7 names with those who prepared the plant-specific SE.}
8 9 Principal Contributors: C. Tilton, NRR/DSS 10 M. Razzaque, NRR/DSS 11 12 Date: