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'''TSTF-580''' is a followup to [[TSTF-566]] =text= {{#Wiki_filter: ==1. SUMMARY DESCRIPTION== The proposed change provides a Technical Specifications (TS) exception to entering Mode 4 if both required Residual Heat Removal (RHR) shutdown cooling subsystems are inoperable. The proposed change modifies NUREG-1433, "Standard Technical Specifications, General Electric BWR/4 Plants," and NUREG-1434, "Standard Technical Specifications, General Electric BWR/6 Plants."<ref>1 NUREG 1433 is based on the BWR/4 plant design, but is also representative of the BWR/2, BWR/3, and, in this case, BWR/5 designs. NUREG 1434 is based on the BWR/6 plant design.</ref> ==2. DETAILED DESCRIPTION== ===2.1. System Design and Operation=== ====RHR System==== The RHR System consists of at least two redundant subsystems. Each subsystem contains at least one motor driven pump, a heat exchanger, and associated piping, valves, and instrumentation. The heat exchanger is cooled by the ultimate heat sink using a safety related cooling system. In NUREG-1433, the safety related cooling system is called the RHR Service Water (RHRSW) system, and in NUREG-1434, it is called the Standby Service Water (SSW) System, but the plant-specific names vary. In this traveler, the name RHRSW System will be used to describe the safety related cooling water system used to transfer heat from the RHR heat exchangers to the ultimate heat sink. The RHR System is a multipurpose system with up to seven operating modes depending on the plant design: 1. Low Pressure Coolant Injection (LPCI) Mode In LPCI mode the RHR System is part of the Emergency Core Cooling System (ECCS) and is used to maintain the reactor pressure vessel (RPV) coolant inventory following a loss of coolant accident (LOCA). The LPCI mode is the normal valve lineup during plant operation and is the only automatically started mode of operation. Both RHR subsystems in LPCI mode are automatically started based on low reactor water level and high drywell pressure. During LPCI operation, the RHR pumps take water from the suppression pool and discharge to the RPV via the recirculation system discharge piping. If reactor pressure is less than the pump shutoff head, the discharge check valves open to permit flow into the RPV. If reactor pressure is above the shutoff head, the minimum flow valves open to allow sufficient flow to the suppression pool to cool the pumps. 2. Containment Spray Mode The containment spray mode is manually aligned and started by the operator. It is used to condense steam and reduce airborne activity in the primary containment following a LOCA. Water is pumped from the suppression pool through the RHR heat exchanger to the containment spray spargers located in the upper portion of the drywell and the suppression chamber. 3. Suppression Pool Cooling Mode Suppression pool cooling is used to maintain suppression pool temperature within limit during normal plant operating conditions and to limit the suppression pool temperature following a LOCA. Water is pumped from the suppression pool through the RHR heat exchanger and back to the suppression pool. The suppression pool cooling mode is manually configured and started by the operator. Each RHR pump is interlocked with all of the shutdown cooling and suppression pool valves which can isolate the suction path for that pump. All the valves in at least one flow path must be fully open before that RHR pump can be started. If an RHR pump is running and a valve in its suction path is moved out of the fully open position, the pump is automatically stopped. 4. Shutdown Cooling The shutdown cooling mode is placed in operation during a normal reactor shutdown and cooldown to remove decay heat. When reactor temperature and pressure have decreased to sufficiently low values, the RHR System is manually placed in the shutdown cooling mode of operation. This mode is capable of cooling the reactor coolant system to approximately 125°F and maintaining the water below that temperature to accommodate refueling operation. Water is removed from one recirculation loop suction piping, cooled by the RHR heat exchanger, and discharged back to one of the recirculation loop discharge lines. 5. Steam Condensing Mode The steam condensing mode is manually aligned to support the Reactor Core Isolation Cooling (RCIC) System to remove decay heat when the main condenser is unavailable. Steam is removed from the high pressure ECCS steam supply line, cooled by the RHR heat exchangers, and pumped back to the RPV by the RCIC System. This mode of operation is not applicable to all BWR plants. 6. Standby Coolant Supply Mode The standby coolant supply mode is used for post-accident recovery. The RHR Service Water system is connected to the RHR System and used to fill the primary containment to a level above the reactor core. 7. Fuel Pool Cooling Mode The fuel pool cooling mode may be used to augment the heat removal capacity of the Fuel Pool Cooling and Cleanup system if needed. ====Decay Heat Removal==== Mode 3 (hot shutdown) is defined in Table 1.1-1 of the TS as the reactor mode switch in "Shutdown" and the average reactor coolant temperature > [200]℉, and Mode 4 is defined as the reactor mode switch in "Shutdown" and the average reactor coolant temperature ≤ [200]℉. The transition temperature is plant-specific, but the temperature is close to the boiling point of water. The BWR design features a number of systems that can remove reactor core decay heat after a shutdown while in Mode 3 by injecting water into the RPV and removing decay heat by conversion of water to steam: • Power conversion system (e.g., normal feedwater and steaming to the main condenser) • High Pressure Coolant Injection (HPCI) System – BWR/2, BWR/3, and BWR/4 • Low Pressure Core Spray (LPCS) System • Low Pressure Coolant Injection (LPCI) System • Reactor Core Isolation Cooling (RCIC) System • The RHR System (below the RHR cut-in permissive pressure) • Control Rod Drive (CRD) System • High Pressure Core Spray (HPCS) System - BWR/5 and BWR/6 In Mode 4, only the RHR System has the capability to remove a significant amount of decay heat from the reactor because the average reactor coolant temperature is below the boiling point of water. Other methods are available, such as injecting cool water with the CRD System and maintaining water level with the Reactor Water Cleanup System, but their heat removal capability is substantially less than the RHR shutdown cooling subsystems and cannot maintain reactor coolant temperature during periods of high decay heat load. ===2.2. Current Technical Specifications Requirements=== Not all of the RHR System operating modes are described in the TS. The following TS provide requirements on various RHR System operating modes. • BWR/4 TS 3.4.8 and BWR/6 TS 3.4.9, "Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown," requires two RHR shutdown cooling subsystems to be operable in Mode 3 when the reactor steam dome pressure is less than the RHR cut-in permissive pressure. TSTF-566-A, "Revise Actions for Inoperable RHR Shutdown Cooling Subsystems," approved by the NRC on February 21, 2019, revised the Actions of these TS to permit establishing alternative decay heat removal mechanisms and to remain in Mode 3 when both required RHR shutdown cooling subsystems are inoperable. • BWR/4 TS 3.4.9 and BWR/6 TS 3.4.10, "Residual Heat Removal (RHR) Shutdown Cooling System - Cold Shutdown," requires two RHR shutdown cooling subsystems to be operable in Mode 4. • BWR/4 and BWR/6 TS 3.5.1, "ECCS - Operating," requires each LPCI and LPCS subsystem to be operable in Modes 1, 2, and 3. If the required RHR Subsystems in LPCI and LPCS mode are inoperable while in Mode 3, LCO 3.0.3 is entered and the plant must be brought to Mode 4 within 37 hours. • BWR/4 and BWR/6 TS 3.5.2, "Reactor Pressure Vessel Water Inventory Control," was renamed and revised by TSTF-542, "Reactor Pressure Vessel Water Inventory Control," and requires one ECCS subsystem, which may be an LPCI subsystem, to be operable in Modes 4 and 5 to mitigate an inadvertent draining event. • BWR/4 and BWR/6 TS 3.6.2.3, "Residual Heat Removal (RHR) Suppression Pool Cooling," requires two RHR suppression pool cooling subsystems to be operable in Modes 1, 2, and 3. If both required RHR Subsystems in suppression pool cooling mode are inoperable in Mode 3, one must be restored within 8 hours or average reactor coolant temperature must be reduced to Mode 4 in the following 36 hours. • BWR/4 TS 3.6.2.4, "Residual Heat Removal (RHR) Suppression Pool Spray," requires two RHR suppression pool spray subsystems to be operable in Modes 1, 2, and 3. If both required RHR Subsystems in suppression pool spray mode are inoperable in Mode 3, one must be restored within 8 hours. The TS do not require entering Mode 4. • BWR/4 and BWR/6 TS 3.9.8, "Residual Heat Removal (RHR) - High Water Level," require one RHR shutdown cooling subsystem to be operable in Mode 5 with irradiated fuel in the RPV and the water level ≥ [23] ft above the top of the RPV flange. • BWR/4 and BWR/6 TS 3.9.9, "Residual Heat Removal (RHR) - Low Water Level," require two RHR shutdown cooling subsystem to be operable in Mode 5 with irradiated fuel in the RPV and the water level ≤ [23] ft above the top of the RPV flange. In addition, BWR/4 TS 3.7.1, "Residual Heat Removal Service Water (RHRSW) System," and BWR/6 TS 3.7.1, "[Standby Service Water (SSW)] System and [Ultimate Heat Sink (UHS)]," require two RHRSW subsystems or SSW subsystems to be operable to support the RHR System heat exchangers in Modes 1, 2, and 3. If both RHRSW subsystems are inoperable in Mode 3, one subsystem must be restored within 8 hours or the plant must be in Mode 4 within 36 hours. If both SSW subsystems are inoperable in Mode 3, the plant must be in Mode 4 within 36 hours. ===2.3. Reason for the Proposed Change=== In TSTF-566, the TSTF proposed to delete BWR/4 TS 3.4.8 and BWR/6 TS 3.4.9, Required Action A.3, which required the plant to be in Mode 4 within 24 hours when one or two required RHR shutdown cooling subsystems are inoperable. Reducing reactor coolant temperature to less than the boiling point of water eliminates most of the decay heat removal mechanisms. The TSTF proposed that entering Mode 4 should not be dictated by the TS when no RHR shutdown cooling subsystem is operable. The NRC approved the change because if there are no operable RHR shutdown cooling subsystems 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 within the Completion Time. As discussed in Section 2.1, the RHR System can be used in various different operating modes that share many of the same components and, as discussed in Section 2.2, there are multiple TS that provide requirements on the RHR System in its different operating modes. Even though TSTF-566 revised the "RHR Shutdown Cooling System – Hot Shutdown" TS to not require entering Mode 4 with no operable RHR shutdown cooling subsystems, there are other TS that would still require entering Mode 4 for the same condition. For Example: • BWR/4 and BWR/6 TS 3.5.1, "ECCS – Operating," if two inoperable RHR shutdown cooling subsystems results in two inoperable LPCI subsystems, • BWR/4 and BWR/6 TS 3.6.2.3, "Residual Heat Removal (RHR) Suppression Pool Cooling," if two inoperable RHR shutdown cooling subsystems results in two inoperable RHR suppression pool cooling subsystems, or • BWR/4 TS 3.7.1, RHRSW System, if two RHRSW subsystems are inoperable. Given the design of the system, it is difficult to construct a scenario in which two inoperable RHR shutdown cooling subsystems in Mode 3 would not also render the corresponding LPCI and RHR suppression pool cooling modes inoperable. Therefore, contrary to the intent of TSTF-566, the TS may still require entering Mode 4 with no operable RHR shutdown cooling subsystems. Should both subsystems of the RHRSW System become inoperable, both required subsystems of the RHR System in the LPCI, RHR shutdown cooling, and RHR suppression pool cooling modes would also be inoperable and would require transition to Mode 4, even though the RHR heat exchangers would not have RHRSW cooling. Therefore, the TS should be revised to not require transition to Mode 4 with no operable RHR subsystems as it may not be possible to reduce the reactor coolant system temperature to the Mode 4 entry condition within the Completion Time. ===2.4. Description of the Proposed Change=== The proposed change would provide an exception from TS requirements to enter Mode 4 if the required RHR shutdown cooling subsystems are inoperable. Any TS Required Action directing entry into Mode 4 would be suspended by this proposed change, regardless of whether it is related to RHR shutdown cooling, until at least one RHR shutdown cooling subsystem is restored to operable status. If there is a circumstance that rendered both required LPCI subsystems, both required RHR suppression pool cooling subsystems, or both RHRSW subsystems inoperable but that did not render the RHR shutdown cooling function inoperable, the exception would not apply. Adoption of this change is dependent on previous adoption of TSTF-566-A, "Revise Actions for Inoperable RHR Shutdown Cooling Subsystems." The attached TS markups are made on the completed but not yet published Revision 5 of NUREG-1433 and NUREG-1434, which incorporates the changes to BWR/4 TS 3.4.8 and BWR/6 TS 3.4.9 approved in TSTF-566. The proposed change is implemented as Notes to BWR/4 TS 3.4.8 and BWR/6 TS 3.4.9, "Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown." • Condition A is revised from, "One or two RHR shutdown cooling subsystems inoperable," to "One [required] RHR shutdown cooling subsystems inoperable." The Action is revised to be applicable to a single inoperable subsystem. • Condition B, "Required Action and associated Completion Time of Condition A not met," is revised to be applicable to a single inoperable RHR shutdown cooling subsystem. • A new Condition C is added which is applicable when two [required] RHR shutdown cooling subsystems are inoperable. o Required Action C.1 is similar to Required Action A.1 and requires verification of an alternate method of decay heat removal within one hour and every 24 hours thereafter. • A new Condition D, "Required Action and associated Completion Time of Condition C not met," is added. o Proposed Required Action D.1 requires immediate initiation of action to restore an RHR shutdown cooling subsystem to operable status. o There is a Note applicable to Required Action D.1 which states, "LCO 3.0.3 and all other LCO Required Actions requiring a MODE change to MODE 4 may be suspended until one RHR shutdown cooling subsystem is restored to OPERABLE status." • Action C is renumbered Action E with no other changes. The TS Bases are revised to reflect the changes to the TS. The regulation at Title 10 of the Code of Federal Regulations (10 CFR), Part 50.36, states, "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." A licensee may make changes to the TS Bases without prior NRC review and approval in accordance with the Technical Specifications Bases Control Program. The proposed TS Bases changes are consistent with the proposed TS changes and provide the purpose for each requirement in the specification consistent with the Commission's Final Policy Statement on Technical Specifications Improvements for Nuclear Power Reactors, dated July 2, 1993 (58 FR 39132). Therefore, the Bases changes are provided for information and approval of the Bases is not requested. A model application is attached. The model may be used by licensees desiring to adopt the traveler following NRC approval. ==3. TECHNICAL EVALUATION== The purpose of the BWR/4 TS 3.4.8 and BWR/6 TS 3.4.9, "Residual Heat Removal (RHR) Shutdown Cooling System - Hot Shutdown," actions is to provide appropriate remedial measures that must be taken in response to a condition in which one or more required RHR shutdown cooling subsystems are inoperable. As discussed in Section 2.1, when the RCS average water temperature is close to or above the boiling point of water, there are several available mechanisms to remove decay heat from the reactor, such as steaming to the main condenser, the RCIC System, LPCS, LPCI, and the RHR shutdown cooling system (if below the cut-in permissive pressure). However, if the average reactor coolant temperature is significantly below the boiling point of water as in Mode 4, the methods of removing decay heat are substantially reduced. Only the RHR shutdown cooling system, supported by the RHRSW System, can remove high decay heat loads and maintain reactor coolant temperature. At low decay heat loads, a system such as reactor water cleanup can remove decay heat and maintain reactor coolant temperature. Without an operable RHR shutdown cooling subsystem, it is unlikely that, following a reactor shutdown, the average reactor coolant temperature could be reduced to Mode 4 within the Completion Time. Other than the TS, there is no design or other regulatory requirement that a BWR be capable of reducing temperature to Mode 4 with no operable RHR shutdown cooling subsystems. As described in Section 2.2, several modes of the RHR system are required by TS. While it would be possible to modify the LPCI, RHR suppression pool cooling, and RHRSW System TS to provide an exception when there are no operable RHR shutdown cooling subsystems, that would require describing the RHR shutdown cooling subsystem operability requirements in those TS, which would unnecessarily complicate those TS. A more straightforward approach is to provide a global exception to entering Mode 4 with no operable RHR shutdown cooling subsystems in the RHR shutdown cooling TS. This approach is consistent the pressurized water reactor (PWR) Standard Technical Specifications (STS) on Auxiliary Feedwater (AFW) and Emergency Feedwater (TS 3.7.5 in the Babcock & Wilcox STS (NUREG-1430), Westinghouse STS (NUREG-1431), and Combustion Engineering STS (NUREG-1432)). In the condition for no operable AFW trains in Modes 1, 2, or 3, the Required Action is modified by a Note which states, "LCO 3.0.3 and all other LCO Required Actions requiring MODE changes are suspended until one AFW train is restored to OPERABLE status." The Bases describe the Note as, "all required MODE changes are suspended until one AFW train is restored to OPERABLE status. In this case, LCO 3.0.3 is not applicable because it could force the unit into a less safe condition." The proposed change is similar to the PWR AFW exception but is more narrowly applied and limited to entry into Mode 4 with no operable RHR shutdown cooling subsystems. The proposed Note modifying new Required Action D.1 indicates that all required MODE changes to MODE 4 may be suspended until one RHR shutdown cooling subsystem is restored to operable status. In this case, LCO 3.0.3 and other Required Actions directing entry into MODE 4 are not applicable because it could force the unit into a less safe condition in which there are no adequate means to remove decay heat. The proposed note would not exempt a requirement to transition to Mode 3 but would remove the requirement to transition to Mode 4 with no operable RHR shutdown cooling subsystems. Entry into Mode 4 should not be dictated by the TS when no RHR shutdown cooling subsystem is operable. When at least one RHR subsystem is restored to operable status, the Completion Times of LCO 3.0.3 or other Required Actions would resume at the point at which they were suspended. The addition of the Note is acceptable because the Required Actions would continue to establish appropriate remedial actions to the degraded condition in order to minimize risk. Immediate action to restore an RHR shutdown cooling subsystem to operable status is required when the exception is applied. It is appropriate to allow the restoration of one of the RHR shutdown cooling subsystems before requiring entry into a condition in which that subsystem would be needed and exiting a condition where other sources of cooling are available. The bracketed word “required” is added to Conditions A and new Condition C to be used for plants that are designed with more than two RHR shutdown cooling subsystems (e.g., Peach Bottom, Dresden, and Brunswick designs include two RHR shutdown cooling subsystems per RHR System loop resulting in four RHR shutdown cooling subsystems.) Required Action C.1 is similar to Required Action A.1 and preserves the current TS Required Action for two inoperable RHR shutdown cooling subsystems. New Required Action D.1 requires immediate initiation of action to restore at least one inoperable subsystem to operable status and is the appropriate action to pursue, similar to existing Action B.1. Restoring at least one decay heat removal path allows a plant cooldown to continue to Mode 4. The immediate Completion Time reflects the importance of restoring a normal path for heat removal. Traveler TSTF-566, Revision 0, proposed to delete a Required Action for the plant to be in Mode 4 within 24 hours when two RHR shutdown cooling subsystems are inoperable. The NRC found the change to be acceptable because 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 Completion Time. The NRC staff also found the deletion of the Required Action acceptable because remaining in Mode 3 allows fission product decay heat and other residual heat from the reactor core to be transferred at a rate such that specified acceptable fuel design limits and the design conditions of the reactor coolant pressure boundary will not be exceeded. ==4. REGULATORY EVALUATION== ===4.1. Applicable Regulatory Requirements/Criteria=== Section IV, "The Commission Policy," of the "Final Policy Statement on Technical Specifications Improvements for Nuclear Power Reactors" (58 Federal Register 39132), dated July 22, 1993, states in part: The purpose of Technical Specifications is to impose those conditions or limitations upon reactor operation necessary to obviate the possibility of an abnormal situation or event giving rise to an immediate threat to the public health and safety by identifying those features that are of controlling importance to safety and establishing on them certain conditions of operation which cannot be changed without prior Commission approval. …[T]he Commission will also entertain requests to adopt portions of the improved STS, even if the licensee does not adopt all STS improvements. …The Commission encourages all licensees who submit Technical Specification related submittals based on this Policy Statement to emphasize human factors principles. …In accordance with this Policy Statement, improved STS have been developed and will be maintained for [BWR designs]. The Commission encourages licensees to use the improved STS as the basis for plant-specific Technical Specifications. …[I]t is the Commission intent that the wording and Bases of the improved STS be used … to the extent practicable. As described in the Commission’s "Final Policy Statement on Technical Specifications Improvements for Nuclear Power Reactors," recommendations were made by NRC and industry task groups for new STS that include greater emphasis on human factors principles in order to add clarity and understanding to the text of the STS, and provide improvements to the Bases of STS, which provides the purpose for each requirement in the specification. Improved vendorspecific STS were developed and issued by the NRC in September 1992. The regulation at Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36(a)(1) requires an applicant for an operating license to include in the application proposed TS in accordance with the requirements of 10 CFR 50.36. The applicant must include in the application a "summary statement of the bases or reasons for such specifications, other than those covering administrative controls…." However, per 10 CFR 50.36(a)(1), these technical specification bases "shall not become part of the technical specifications." The Final Policy Statement provides the following description of the scope and the purpose of the Technical Specification Bases: Appropriate Surveillance Requirements and Actions should be retained for each LCO [limiting condition for operation] which remains or is included in the Technical Specifications. Each LCO, Action, and Surveillance Requirement should have supporting Bases. The Bases should at a minimum address the following questions and cite references to appropriate licensing documentation (e.g., FSAR [final safety analysis report], Topical Report) to support the Bases. 1. What is the justification for the Technical Specification, i.e., which Policy Statement criterion requires it to be in the Technical Specifications? 2. What are the Bases for each LCO, i.e., why was it determined to be the lowest functional capability or performance level for the system or component in question necessary for safe operation of the facility and, what are the reasons for the Applicability of the LCO? 3. What are the Bases for each Action, i.e., why should this remedial action be taken if the associated LCO cannot be met; how does this Action relate to other Actions associated with the LCO; and what justifies continued operation of the system or component at the reduced state from the state specified in the LCO for the allowed time period? 4. What are the Bases for each Safety Limit? 5. What are the Bases for each Surveillance Requirement and Surveillance Frequency; i.e., what specific functional requirement is the surveillance designed to verify? Why is this surveillance necessary at the specified frequency to assure that the system or component function is maintained, that facility operation will be within the Safety Limits, and that the LCO will be met? Note: In answering these questions the Bases for each number (e.g., Allowable Value, Response Time, Completion Time, Surveillance Frequency), state, condition, and definition (e.g., operability) should be clearly specified. As an example, a number might be based on engineering judgment, past experience, or PSA [probabilistic safety assessment] insights; but this should be clearly stated. Additionally, 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 categories of items required to be in the TS are provided in 10 CFR 50.36(c). As required by 10 CFR 50.36(c)(2)(i), the TS will include LCOs, which are the lowest functional capability or performance levels of equipment required for safe operation of the facility. Per 10 CFR 50.36(c)(2)(i), when an LCO of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the TS until the condition can be met. The regulation at 10 CFR 50.36(c)(3) requires TS to include items in the category of SRs, which are requirements relating to test, calibration, or inspection to assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the LCOs will be met. Per 10 CFR 50.90, whenever a holder of a license desires to amend the license, application for an amendment must be filed with the Commission, fully describing the changes desired, and following as far as applicable, the form prescribed for original applications. Per 10 CFR 50.92(a), in determining whether an amendment to a license will be issued to the applicant, the Commission will be guided by the considerations which govern the issuance of initial licenses to the extent applicable and appropriate. The NRC staff’s guidance for the review of TS is in Chapter 16, "Technical Specifications," of NUREG-0800, Revision 3, "Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants" (SRP), dated March 2010 (ADAMS Accession No. ML100351425). As TSTF-580, Rev. 1 Page 11 described therein, as part of the regulatory standardization effort, the NRC staff has prepared Standard Technical Specifications for each of the light-water reactor nuclear designs. ===4.2. Conclusions=== In conclusion, based on the considerations discussed above, the proposed revision does not alter the current manner of operation and (1) there is reasonable assurance that the health and safety of the public will not be endangered by continued operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission’s regulations, and (3) the approval of the proposed change will not be inimical to the common defense and security or to the health and safety of the public. ==5. REFERENCES== 1. "GE Technology Manual (R-304B)," US Nuclear Regulatory Commission Technical Training Center. 2. TSTF-566-A, Revision 0, "Revise Actions for Inoperable RHR Shutdown Cooling Subsystems," February 21, 2019. }} <references />

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