ML14261A091
| ML14261A091 | |
| Person / Time | |
|---|---|
| Site: | River Bend  |
| Issue date: | 09/02/2014 |
| From: | Olson E Entergy Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| GL-08-001, RBG-47497 | |
| Download: ML14261A091 (45) | |
Text
Entergy Entergy Operations, Inc.River Bend Station 5485 U.S. Highway 61N St. Francisville, LA 70775 Tel 225-381-4374 Eric Olson Site Vice President RBG-47497 September 2, 2014 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
SUBJECT:
Application for Technical Specification Changes Technical Specification Task Force (TSTF) Improved Standard Technical Specification Change Traveler, TSTF-523, "Generic Letter 2008-01, Managing Gas Accumulation" River Bend Station, Unit 1 Docket No. 50-458 License No. NPF-47
Dear Sir or Madam:
In accordance with the provisions of Section 50.90 of Title 10 of the Code of Federal Regulations (10 CFR), Entergy Operations, Inc. (Entergy) is submitting a request for an amendment to the Technical Specifications (TS) for River Bend Station (RBS), Unit 1.The proposed amendment modifies the existing Surveillance Requirements (SRs) related to gas accumulation for the Emergency Core Cooling Systems (ECCS) and adds new SRs on entrained gas to the specifications governing the Decay Heat Removal (DHR), Residual Heat Removal (RHR), and Shut Down Cooling (SDC) systems. Similar changes are made to the existing SR on the Reactor Core Isolation Cooling (RCIC) System to maintain consistency within the ITS. Existing SRs are revised to verify that these systems are not rendered inoperable due to accumulated gas and to provide allowances to facilitate the performance of the proposed gas accumulation management SRs. The Bases are revised to reflect the change to the SRs.Attachment 1 provides a description of the proposed changes. Attachment 2 provides the existing TS pages marked up to show the proposed changes. Attachment 3 provides the existing TS BASES pages marked up to show the proposed changes. Attachment 4 includes regulatory commitments to be implemented in support of this change.Although this request is neither exigent nor emergency, your prompt review is requested.
Once approved, the amendment shall be implemented within 60 days.JLl RBG-47497 Page 2 of 3 If you have any questions or require additional information, please contact Mr. J. A. Clark at (225) 381-4177.I declare under penalty of perjury that the foregoing is true and correct, executed on September 2, 2014.Sincerely, EO/JAC/bmb Attachments:
- 1. Analysis of Proposed Technical Specification Change 2. Proposed Technical Specification Changes (mark-up)3. Proposed Technical Specification BASES Changes (mark-up for information only)cc: Regional Administrator U. S. Nuclear Regulatory Commission, Region IV 1600 East Lamar Blvd.Arlington, TX 76011-4511 NRC Senior Resident Inspector P. 0. Box 1050 St. Francisville, LA 70775 U. S. Nuclear Regulatory Commission Attn: Mr. Alan Wang MS O-8B1 One White Flint North 11555 Rockville Pike Rockville, MD 20852 Department of Environmental Quality Office of Environmental Compliance Radiological Emergency Planning and Response Section Ji Young Wiley P.O. Box 4312 Baton Rouge, LA 70821-4312 RBG-47497 Page 3 of 3 Public Utility Commission of Texas Attn: PUC Filing Clerk 1701 N. Congress Avenue F-. 0. Box 13326 Austin, TX 78711-3326 RBF1-14-0120 LAR 2014-04 Attachment I RBG-47497 Analysis of Proposed Technical Specification Change RBG-47497 Attachment 1 Page 1 of 4
1.0 DESCRIPTION
The proposed change revises or adds Surveillance Requirements to verify that the system locations susceptible gas accumulation are sufficiently filled with water and to provide allowances which permit performance of the verification.
The changes are being made to address the concerns discussed in Generic Letter 2008-01, "Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems." The proposed amendment is consistent with TSTF-523, Revision 2, "Generic Letter 2008-01, Managing Gas Accumulation." The availability of the model safety evaluation for this TS improvement was announced in the Federal Register as part of the Consolidated Line Item Improvement Process (CLIIP).2.0 ASSESSMENT
2.1 Applicability
of Published Safety Evaluation Entergy has reviewed the model safety evaluation as part of the Federal Register Notice of Availability.
This review included a review of the NRC staff's evaluation, as well as the information provided in TSTF-523.
As described in the subsequent paragraphs, Entergy has concluded that the justifications presented in the TSTF-523 proposal and the model safety evaluation prepared by the NRC staff are applicable to River Bend Station (RBS), Unit 1 and justify this amendment for the incorporation of the changes.Entergy performed evaluations in response to Generic Letter 2008-01 and implemented changes to plant procedures to address the identified conditions.
The evaluations and associated procedures are applicable to TSTF-523 requirements with RBS variations addressed below.2.2 Variations The table below identifies the NUREG-1434 affected Technical Specifications (TS), the corresponding RBS Surveillance Requirements (SR).NUREG-1434 TS / Name Affected RBS SR Notes 3.4.9 RHR Shutdown Cooling System SR 3.4.9.2 See discussion below-Hot Shutdown 3.4.10 RHR Shutdown Cooling SR 3.4.10.2 See discussion below System -Cold Shutdown 3.5.1 ECCS -Operating SR 3.5.1.1 Per TSTF SR 3.5.1.2 3.5.2 ECCS -Shutdown SR 3.5.2.3 Per TSTF SR 3.5.2.4 3.5.3 RCIC System SR 3.5.3.1 Per TSTF SR 3.5.3.2 3.6.1,7 Containment Spray System See discussion below RBG-47497 Attachment 1 Page 2 of 4 3.6.2.3 RHR Suppression Pool SR 3.6.2.3.2 Per TSTF Cooling 3.9.8 RHR -High Water Level SR 3.9.8.2 Per TSTF 3.9.9 RHR -Low Water Level SR 3.9.9.2 Per TSTF For the RHR Shutdown Cooling System, TS 3.4.9 and 3.4.10, the required venting locations will be determined prior to startup from refueling outage (RF) 19 currently scheduled for early 2017. The SR's are modified by a note to identify the implementation date.Entergy is proposing the following variation from the TS changes described in the TSTF-523, Revision 2, or the applicable parts of the NRC staffs model safety evaluation.
RBS does not have a containment spray function as identified in TSTF-523.
Three unit coolers of the reactor building air supply system (HVR) maintain ventilation of the containment building.
These unit coolers are normally supplied by the turbine building chilled water system (HVN). Two of these unit coolers are designed to operate under accident conditions.
This function is identified in USAR chapter 6.2 and TS Section 3.6.1.7.When initiated for their safety function, the two unit coolers are isolated from the chilled water and supplied by Standby Service Water (SSW). The SSW system is designed to prevent potential water hammer resulting from water column separation immediately following a Normal Service Water (NSW) pump trip and subsequent recombination of water columns at high velocity which occurs as the SSW pumps refill the system. For this reason, the SSW system is provided with vacuum release solenoid valves that open automatically to admit clean IAS air stored in safety-related accumulator tanks. Air injects into higher elevation service water lines on a service water header pressure low signal.Additionally, the SSW is provided with air release valves in the high points of the normal service water piping, where air is anticipated to accumulate.
These valves are designed to pass about 7-10 scfm of air and they would fail open with a maximum water leakage rate of 2 gpm. Lesser amounts of unvented air still remaining in the piping are swept out by the SSW flow and exit the system through cooling tower spray headers (Ultimate Heat Sink, UHS).Therefore the changes associated with the containment spray system are not included in this submittal.
The proposed TSTF changes are included in Attachment 2.Corresponding BASES for each affected RBS TS will be modified consistent with the approved TSTF.3.0 REGULATORY ANALYSIS 3.1 No Significant Hazards Consideration Determination RBG-47497 Attachment 1 Page 3 of 4 Entergy requests adoption of TSTF-523, Rev. 1, "Generic Letter 2008-01, Managing Gas Accumulation," which is an approved change to the standard technical specifications (STS), into the River Bend Station, Unit 1 Technical Specifications (TS). The proposed change revises or adds Surveillance Requirements to verify that the system locations susceptible to gas accumulation are sufficiently filled with water to prevent rendering them inoperable due to accumulated gas and to provide allowances which permit performance of the verification.
Entergy has evaluated whether or not a significant hazards consideration is involved with the proposed amendment(s) by focusing on the three standards set forth in 10 CFR 50.92,"Issuance of amendment," as discussed below: 1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?
Response:
No.The proposed change revises or adds SRs that require verification that the Emergency Core Cooling System (ECCS), the Shutdown Cooling (SDC), Residual Heat Removal (RHR), and the Reactor Core Isolation Cooling (RCIC) Systems are not rendered inoperable due to accumulated gas and to provide allowances which permit performance of the revised verification.
Gas accumulation in the subject systems is not an initiator of any accident previously evaluated.
As a result, the probability of any accident previously evaluated is not significantly increased.
The proposed SRs ensure that the subject systems continue to be capable to perform their assumed safety function and are not rendered inoperable due to gas accumulation.
Thus, the consequences of any accident previously evaluated are not significantly increased.
Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.
- 2. Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?
Response:
No.The proposed change revises or adds SRs that require verification that the ECCS, the RHR, SDC, and the RCIC Systems are not rendered inoperable due to accumulated gas and to provide allowances which permit performance of the revised verification.
The proposed change does not involve a physical alteration of the plant (i.e., no new or different type of equipment will be installed) or a change in the methods governing normal plant operation.
In addition, the proposed change does not impose any new or different requirements that could initiate an accident.
The proposed change does not alter assumptions made in the safety analysis and is consistent with the safety analysis assumptions.
Therefore, the proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.
RBG-47497 Attachment 1 Page 4 of 4 3. Does the proposed change involve a significant reduction in a margin of safety?Response:
No.The proposed change revises or adds SRs that require verification that the ECCS, the RHR, SDC, and the RCIC Systems are not rendered inoperable due to accumulated gas and to provide allowances which permit performance of the revised verification.
The proposed change adds new requirements to manage gas accumulation in order to ensure the subject systems are capable of performing their assumed safety functions.
The proposed SRs are more comprehensive than the current SRs and will ensure that the assumptions of the safety analysis are protected.
The proposed change does not adversely affect any current plant safety margins or the reliability of the equipment assumed in the safety analysis.
Therefore, there are no changes being made to any safety analysis assumptions, safety limits or limiting safety system settings that would adversely affect plant safety as a result of the proposed change.Therefore, the proposed change does not involve a significant reduction in a margin of safety.Based on the above, Entergy concludes that the proposed change presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.
4.0 ENVIRONMENTAL
CONSIDERATION The proposed change would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement.
However, the proposed change does not involve (i) a significant hazards consideration, (ii) a significant change in the types or a significant increase in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure.Accordingly, the proposed change meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed change.
7.0 REFERENCES
- 1. Notice of Availability, Federal Register dated January 15, 2014.
Attachment 2 RBG-47497 Proposed Technical Specification Changes (mark-up)Note, markup deletions identified by strikethrough (delete) and additions identified by underline (addition).
RBG-47497 Attachment 2 Page 1 of 8 RHR Shutdown Cooling System -Hot Shutdown 3.4.9 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.9.1 ----------.-.-......---
-- NOTE ---------------------------------
Not required to be met until 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> after reactor steam dome pressure is less than the RHR cut in permissive pressure.Verify one RHR shutdown cooling subsystem or 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> recirculation pump is operating.
SR 3.4.9.2 -------- ..---- -------NOTE -..............
..---------
Not required to be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after reactor steam dome pressure is less than the RHR cut in permissive pressure.Verify RHR shutdown cooling subsystem locations 31 days susceptible to gas accumulation are sufficiently filled with water.Surveillance required after startup from refueling outage 19.RIVER BEND 3.4-24 Amendment No. 81 RBG-47497 Attachment 2 Page 2 of 8 RHR Shutdown Cooling System -Cold Shutdown 3.4.10 ACTIONS (continued)
CONDITION REQUIRED ACTION COMPELETION TIME B. No RHR shutdown cooling B. 1 Verify reactor coolant 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> from discovery subsystem in operation.
circulating by an alternate of no reactor coolant method, circulation AND AND No recirculation pump in operation.
Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter AND B.2 Monitor reactor coolant Once per hour temperature and pressure.SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.10.1 Verify one RHR shutdown cooling subsystem or 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> recirculation pump is operating.
SR 3.4,10.2 Verify RHR shutdown cooling subsystem locations 31 days susceptible to Qas accumulation are sufficiently filled with water.Surveillance required after startuo from refueling outage 19.RIVER BEND 3.4-26 Amendment No. 81 RBG-47497 Attachment 2 Page 3 of 8 ECCS ---. Operating 3,5.1 I SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5,1.1 Verify, for each ECCS injection/spray subsystem, 31 days locations susceptible to das accumulation are sufficien.iy filled with water, the-Ar4gm-&.4le4.with vawete.'rq4eh e- ee e*SR 3.5,1.2 ----------------------------
NOTE -----------....-------.......
- 1. Low pressure coolant injection (LPCI)subsystems may be considered OPERABLE during alignment and operation for decay heat removal with reactor steam dome pressure less than the residual heat removal cut in permissive pressure in MODE 3, if capable of being manually realigned and not otherwise inoperable.
- 2. Not requLred to be met for system vent flow path~s_QpeDed under admninistrative control.Verify each ECCS injection/spray subsystem manual, 31 days power operated, and automatic valve in the flow path, that is not locked, sealed, or otherwise secured in position, is in the correct position.SR 3.5.1.3 Verify ADS accumulator supply pressure is 31 days> 131 psig.S R 3.5.1.4 Verify each ECCS pump develops the specified flow In accordance with rate with the specified pump differential pressure.
the Inservice Testing Program PUMP DIFFERENTIAL SYSTEM FLOW RATE PRESSURE LPCS 5010 gpm 282 psid LPCI 5050 gpm 102 psid HPCS 5010 gpm >415 psid (continued)
RIVER BEND 3.5-4 Amendment No. 81 RBG-47497 Attachment 2 Page 4 of 8 ECCS- Shutdown 3.5.2 SURVEILLANCE REQUIREMENTS (continued)
SURVEILLANCE FREQUENCY SR 3.5.2.2 Verify, for the required High Pressure Core Spray 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> (HPCS) System, the: a. Suppression pool water level is ; 13 ft 3 inches;or b. Condensate storage tank water level is > 11 ft 1 inch.SR 3.5.2.3 Verify, for each required ECCS injection/spray 31 days subsystem, locations susceptible to gas accumulation are sufficiently filled with water. -peip-_g4s-ifilled SR 3.5.2.4 --------.-.-
........---------
NOTE ---.-.----.---.----------
- 1. One low pressure coolant injection (LPCI)subsystem may be considered OPERABLE during alignment and operation for decay heat removal, if capable of being manually realigned and not otherwise inoperable.
2,. Not required to be met for system flow roaths opened under administrative control Verify each required ECCS injection/spray subsystem 31 days manual, power operated, and automatic valve in the flow path, that is not locked, sealed, or otherwise secured in position, is in the correct position.(continued)
RIVER BEND Amendment No. 81 RBG-47497 Attachment 2 Page 5 of 8 RCIC System 3.5.3 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.3.1 Verify the RCIC System locations susceptible to gas 31 days accumulation are sufficiently full with water._. P1!-i!SR 3.5.3.2 --------------.............
NOTE -----. ------.---------------
31 days:Not required to be met for sytem vent flow ,aths o!ened under administrative control Verify each RCIC System manual, power operated, and automatic valve in the flow path, that is not locked, sealed, or otherwise secured in position, is in the correct position.SR 3.5.3.3 .NOTE........-----------------
.-----Not required to be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after reactor steam pressure and flow are adequate to perform the test..............................................................
Verify, with RCIC steam supply pressure < 1075 psig 92 days and > 920 psig, the RCIC pump can develop a flow rate >_ 600 gpm against a system head corresponding to reactor pressure.SR 3.5.3.4 -------------------
NOTE -.-----------------
Not required to be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after reactor steam pressure and flow are adequate to perform the test.Verify, with RCIC steam supply pressure:..
165 psig 1 24 months and 150 psig, the RCIC pump can develop a flow rate a 600 gpm against a system head corresponding to reactor Pressure.(continued)
RIVER BEND 3.5-11 Amendment No.94-444, 168 RBG-47497 Attachment 2 Page 6 of 8 RHR Suppression Pool Cooling 3.6.2.3 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.6.2.3.1 Verify each RHR suppression pool cooling 31 days subsystem manual, power operated, and automatic valve in the flow path that is not locked, sealed, or otherwise secured in position is in the correct position or can be aligned to the correct position.SR 3.6.2,3.2 Verify RHR suppression pool cooling subsystem 31.days locations susceptible to gas accumulation are sufficiently filled with water.SR 3.6.2.3.3-2 Verify each RHR pump develops a flow rate In accordance
?! 5050 gpm through the associated heat with the Inservice exchangers to the suppression pool. Testing Program RIVER BEND 3.6-38 Amendment No. 81 RBG-47497 Attachment 2 Page 7 of 8 RHR -High Water Level 3.9.8 I f ACTIONS (continued)_
CONDITION REQUIRED ACTION COMPLETION TIME B. (continued)
B.3 -------r---- NOTE-----Entry and exit is permissible under administrative control.Initiate action to close Immediately one door in each primary containment air lock.C. No RHR shutdown cooling C.1 Verify reactor coolant 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> from discovery subsystem in operation, circulation by an of no reactor coolant alternate method. circulation AND Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter AND Once per hour C.2 Monitor reactor coolant temperature.
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.9.8.1 Verify one RHR shutdown cooling subsystem is 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> operating.
SR 3.9.8.2 Verif).?vired RHR shu-tdown cooiingaýsub4 31 daysýlocations susceptible to gas accumulation are sufficientlv filled with water.RIVER BFND 3.9-11 Amendment No. 81 RBG-47497 Attachment 2 Page 8 of 8 RHR -Low Water Level 3.9,9 ACTIONS (continped)
CONDITION REQUIRED ACTION. COMPLETION TIME B. (continued)
B,2 --....----
NOTE -----------
Entry and exit is permissible under administrative control.Initiate action to close Immediately one door in each primary containment air lock.C. No RHR shutdown cooling C.1 Verify reactor coolant 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> from discovery subsystem in operation.
circulation by an of no reactor coolant alternate method: circulation AND Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter AND C.2 Monitor reactor coolant Once per hour temperature.
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.9,9.1 Verify one RHR shutdown cooling subsystem is 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> operating.
SR 3,99.2 Verity reuied ,R shutdown orthnus 1;ocations susceotrbie to -gas accurnu!ation are sufficientlyjild With water.RIVER BEND 3.9-13 Amernndment No, 81 Attachment 3 RBG-47497 Proposed Technical Specification BASES Changes (mark-up)For Information Only Note, markup deletions identified by strikethrough (delete) and additions identified by underline (addition).
RBG-4749 7 Attachment 3 Page 1 of 25 RHR Shutdown Cooling System -Hot Shutdown B 3.4.9 BASES LCO (continued) aligned (remote or local) in the shutdown cooling mode for removal of decay heat. In MODE 3, one RHR shutdown cooling subsystem can provide the required cooling, but two subsystems are required to be OPERABLE to provide redundancy.
Operation of one subsystem can maintain or reduce the reactor coolant temperature as required.
However, to ensure adequate core flow to allow for accurate average reactor coolant temperature monitoring, nearly continuous operation is required.Management of gas voids is important to RHR Shutdown Cooling System OPERABILITY, Note 1 permits both RHR shutdown cooling subsystems and recirculation pumps to be shut down for a period of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in an 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period. Note 2 allows one RHR shutdown cooling subsystem to be inoperable for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for performance of surveillance tests. These tests may be on the affected RHR System or on some other plant system or component that necessitates placing the RHR System in an inoperable status during the performance.
This is permitted because the core heat generation can be low enough and the heatup rate slow enough to allow some changes to the RHR subsystems or other operations requiring RHR flow interruption and loss of redundancy.
APPLICABILITY In MODES 1 and 2, and in MODE 3 with reactor steam dome pressure greater than or equal to the RHR cut in permissive pressure, this LCO is not applicable.
Operation of the RHR System in the shutdown cooling mode is not allowed above this pressure because the RCS pressure may exceed the design pressure of the shutdown cooling piping. Decay heat removal at reactor pressures greater than or equal to the RHR cut in permissive pressure is typically accomplished by condensing the steam in the main condenser.
Additionally, in MODE 2 below this pressure, the OPERABILITY requirements for the Emergency Core Cooling Systems (ECCS) (LCO 3.5.1, "ECCS-Operating")
do not allow placing the RHR shutdown cooling subsystem into operation.
Otherwise, a recirculation pump is required to be in operation.
In MODE 3 with reactor steam dome pressure below the RHR cut in permissive pressure (i.e., the actual pressure at which the interlock resets)the RHR System may be operated in the shutdown cooling mode to remove decay heat to reduce or maintain coolant temperature.(continued)
RIVER BEND B 314-44 Reviscion No, 0 RBG-47497 Attachment 3 Page 2 of 25 RHR Shutdown Cooling System -Hot Shutdown B 3,4.9 BASES ACTIONS B.1, B.2, and B.3 (continued)
During the period when the reactor coolant is being circulated by an alternate method (other than by the required RHR shutdown cooling subsystem or recirculation pump), the reactor coolant temperature and pressure must be periodically monitored to ensure proper function of the alternate method. The once per hour Completion Time is deemed appropriate.
SURVEILLANCE SR 3.4.9.1 REQUIREMENTS This Surveillance verifies that one RHR shutdown cooling subsystem or recirculation pump is in operation and circulating reactor coolant. The required flow rate is determined by the flow rate necessary to provide sufficient decay heat removal capability.
The Frequency of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is sufficient in view of other visual and audible indications available to the operator for monitoring the RHR subsystem in the control room.This Surveillance is modified by a Note allowing sufficient time to align the RHR System for shutdown cooling operation after clearing the pressure interlock that isolates the system, or for placing a recirculation pump in operation.
The Note takes exception to the requirements of the Surveillance being met (i.e., forced coolant circulation is not required for this initial 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> period), which also allows entry into the Applicability of this Specification in accordance with SR 3.0.4 since the Surveillance will not be "not met" at the time of entry into the Applicability.
5R 3.4.9.2 RHR Shutdown Cooling System piping and components have the potential to develoo voids and pockets of entrained gases. Preventing and managing -gas intrus.ion and accumulation is necessary for oroper operation of the RHR shutdown cooling subsystems and may also prevent water hammer. pump cavitation, and oumpiu g of noncondensibie gas into the reactor vessel.Selection of RHR Shutdown Coo~li.Sostern locations susceotile to_ aas accumulation is based on a review of system desian information, including piping and instrumentation drawi ngs. isometric drawings.
Iar and elevation drawinas and The desig, review is. u loiemented bsye k downs to validate the svstem hiah Doints ano to confirm the location and orientation of imoortan comoonents that can become sources of gas or could otherwise cause gas to be traed _srodor difficuit to ,remove during system maintenance or restoration.
Susceptible locations don ant and sstem iuration, such as stand-by versus operating]
coInditions.
The RHR Shutdown Coohn , s OPERABLE whn its sufficientvith .vafer. Acceo..` nce crý-teria are established for the volume of RIVER BEND B .3.4-47 Revision No. 0 RBG-47497 Attachment 3 Page 3 of 25 RHR Shutdown Cooling System -Hot Shutdown B 3.4.9 BASES accumulated oas at susceptibie locations.
If accumulatedgas is discovered that exceeds the acceptance criteria for the susce.tible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Coolinq System is not rendered inooerable by the accumulated gas (i.e.. the system is sufficiently filled with waterl, the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.RHR Shutdown Cooling System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is comnoared to the acceptance criteria for the location.
Susceptible locations in the same system flow path which are subiect to the same gas intrusion mechanisms may be verified by monitorinQ a representative sub-set of susceptible locations.
Monitoring may not be-practical for locations that are inaccessible due to radiological or environmental conditiorts the olant configuration, or personnel safety. For these locations alternative methods Ie.g., operating parameters, remote rngnitoringi may be-used to monitor the susceptible location, Monitorina is not required for susceptible locations where the maximum potential accumulated cas void volume has been evaluated and determined to not challenge system OPERABILiTY, The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.This SR is modified by a Note that states the SR is not required to be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> reactor steam dome pressure is < (the RHR cut in permissive pressurel.
In a rapid shutdown, there mav be insufficient time to verify all susceotible locations prior to entering the Applicabilit'.
The 31 day Frequency takes into consideration the gradual nature of qas accumulation in the RHR Shutdown Cooling System piping and the procedural coD;troL.jgoverni
- n. system operation.
REFERENCES None.RWVER BEND 8 3.4-47 Revision No. 0 RBG-47497 Attachment 3 Page 4 of 25 RHR Shutdown Cooling System-Cold Shutdown B 3.4.10 BASES LCO (continued) aligned (remote or local) in the shutdown cooling mode for removal of decay heat. In MODE 4, one RHR shutdown cooling subsystem can provide the required cooling, but two subsystems are required to be OPERABLE to provide redundancy.
Operation of one subsystem can maintain and reduce the reactor coolant temperature as required.However, to ensure adequate core flow to allow for accurate average reactor coolant temperature monitoring, nearly continuous operation is required.
Management of Qas voids is rmoorant to RHR Shutdown Coolino System OPERABILITY.
I Note 1 permits both RHR shutdown cooling subsystems and recirculation pumps to be shut down for a period of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in an 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period. Note 2 allows one RHR shutdown cooling subsystem to be inoperable for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for performance of surveillance tests. These tests may be on the affected RHR System or on some other plant system or component that necessitates placing the RHR System in an inoperable status during the performance.
This is permitted because the core heat generation can be low enough and the heatup rate slow enough to allow some changes to the RHR subsystems or other operations requiring RHR flow interruption and loss of redundancy.
Note 3 permits both RHR shutdown cooling subsystems and recirculation pumps to be shut down during performance of inservice leak testing and during hydrostatic testing. This is permitted because RCS pressures and temperatures are being closely monitored as required by LCO 3.4.11.APPLICABILITY In MODES 1 and 2, and in MODE 3 with reactor steam dome pressure greater than or equal to the RHR cut in permissive pressure, this LCO is not applicable.
Operation of the RHR System in the shutdown cooling mode is not allowed above this pressure because the RCS pressure may exceed the design pressure of the shutdown cooling piping. Decay heat removal at reactor pressures greater than or equal to the RHR cut in permissive pressure is typically accomplished by condensing the steam in the main condenser.
Additionally, in MODE 2 below this pressure, the OPERABILITY requirements for the Emergency Core Cooling Systems (ECCS) (LCO 3.5.1, "ECCS--Operating")
do not allow.placing the RHR shutdown cooling subsystem into operation.
_______(continued)
RIVER BEND B 3.4-49 Revision No. 0 RBG-47497 Attachment 3 Page 5 of 25 RHR Shutdown Cooling System-Cold Shutdown B 34.10 BASES SURVEILLANCE SR 3.4.10.1 (continued)
REQUIREMENTS determined by the flow rate necessary to provide sufficient decay heat removal capability.
The Frequency of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is sufficient in view of other visual and audible indications available to the operator for monitoring the RHR subsystem in the control room.SR 3.4.10.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained aases. Preventinn and managing pas intrusion and accumulation is necessary for pro__operation of the RHR shutdown coolincl subsystems and may also prevent water hammer. pump cavitation, and prnmina of noncondensible gas into the reactor vessel.Selection of RHR Shutdown Cooling System locations susceptibie toga accumulation is based on a review of system design information, including piping and instrumentation drawings.
isometric drawings, plan and elevation drawings, and calculations, The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration.
Susceotible locations depend on plant and system configuration, such as stand-by versus operating conditions.
The RHR Shutdown Cooiing System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated aas at susceptible locations.
If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible locatio.n opr the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for pas volume at the suction or* discharge of a pump), the Surveillance is not met. if it is determined by subseouent evaluation that the RHR Shutdown Cooling System is rnot.rendered inoperable by the accumulated gas fi the system is sufficiently filled with waterl, the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.RHR Shutdown stem locations susceptibie to g4s acc un.iiation are monitored and, if cps is found the9 ags vOlume is cornpared to the acceotance criteria for the location.
Suscentible locations in the samie system flow path whirsuectothesame .as intrusion rrlngechanms may be verified _y_.monit.ringq a representative sub-set of susceptible iocations.
Monitoring may not be oracticel for locations that are inaccessibie due to radiological or environmental conditions, the tiant confLration or personnel safety. For these iocations alternative methods-L ..
rameters, rernote mont mav be used to monitor the susceptible_ýocation.
Monitoring is not required for suscreptible locations whereotentia accmated icas void volume has RIVER BEND B 3.4-52 Revision No. 0 RBG-47497 Attachment 3 Page 6 of 25 RHR Shutdown Cooling System-Cold Shutdown B 34.10 BASES been evaluated and determined to not challenle system OPERABILITY.
The accuracy of the nriethod used for monitoring the susceotible locations and trendingq of the results should be sufficient to assure system OPERABILITY during the Surveillance intervai.The 31 day Frequency takes into consideration the gradual nature of gas accumulation in the RHR Shutdown Cooling System piping and the procedural controls gioverning system operation.
REFERENCES None.RIVER BEND B 3,4-52 Revision No. 0 RBG-47497 Attachment 3 Page 7 of 25 ECCS--Operating B 3.5.1 BASES (continued)
LCO Each ECCS injection/spray subsystem and seven ADS valves are required to be OPERABLE.
The ECCS injection/spray subsystems are the three LPCI subsystems, the LPCS System, and the HPCS System.The ECCS injection/spray subsystems are further subdivided into the following groups: Management of gas voids is imoortant to ECCS iniection/spray subsvstem OPERABILITY.
a) The low pressure ECCS injection/spray subsystems are the LPCS System and the three LPCI subsystems; b) The ECCS injection subsystems are the three LPCI subsystems; and c) The ECCS spray subsystems are the HPCS System and the LPCS System.With less than the required number of ECCS subsystems OPERABLE during a limiting design basis LOCA concurrent with the worst case single failure, the limits specified in 10 CFR 50.46 (Ref. 10) could potentially be exceeded.
All ECCS subsystems must therefore be OPERABLE to satisfy the single failure criterion required by 10 CFR 50.46 (Ref. 10).LPCI subsystems may be considered OPERABLE during alignment and operation for decay heat removal when below the actual RHR cut in permissive pressure in MODE 3, if capable of being manually realigned (remote or local) to the LPCI mode and not otherwise inoperable.
At these low pressures and decay heat levels, a reduced complement of ECCS subsystems should provide the required core cooling, thereby allowing operation of RHR shutdown cooling when necessary.
I APPLICABILITY All ECCS subsystems are required to be OPERABLE during MODES 1, 2, and 3 when there is considerable energy in the reactor core and core cooling would be required to prevent fuel damage in the event of a break in the primary system piping. In MODES 2 and 3, the ADS function is not required when pressure is _ 100 psig because the low pressure ECCS subsystems (LPCS and LPCI) are capabte of providing flow into the RPV below this pressure.
ECCS requirements for MODES 4 and 5 are specified in LCO 3.5.2, "ECCS- Shutdown." (continued)
RIVER BEND B 3,5-5 Revýsion No. 0 RBG-47497 Attachment 3 Page 8 of 25 ECCS-Operating B 3.5.1 BASES (continued)
SURVEILLANCE SR 3.5.1.1 REQUIREMENTS REURMNS The f!ow pathl piping has the petential to cevis-.ek4o air. o4aintainiqng the the syst ms wili efr rpry incti heir WP~ ca-aciy no h EGGS .itlatioenF igal. Or .soabsu4--wer-e-a fui is to vent ate g .The ECCS iniection/spray subsystem flow path oiing and components have the potential to develop voids and pockets of entrained gases, Preventing and managing gas intrusion and accumulation is necessar/for propjer operation of the ECCS injection/spray subsystems and may also prevent a water hammer, pump cavitation, and oumpino of noncondensible gas into the reactor vessel Selection of ECCS inlection/spray subsystem locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawin s, plan and elevation drawings, and calculations.
The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapoed or difficult to remove during system maintenance or restoration.
Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.
The ECCS iniection/spray subsystem is OPERABLE when it is suff iciently filied with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations.
If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated qas at one or more susceptible locations exceeds an acceptance criteria for Qas volume at the suction or discharge of a putpn, the Surveillance is not met. if it is determined by subsequent evaluation that the ECCS iniectlonisoray subsystems are not rendered inorerabie by the accumulated gas i.te. the system is filled with wateri, the,_l____
be declared met.Accumulated gas should be eliminated or brought within the acce tarce criteria limits.ECCS.inj,,ection/r.subsystem locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is ompared to the acceptance criteria for the location.
Susceptible locations in the same system flow path which are subiect to ,te same gas intrusion mechanisms may be verified by mronirrino a reoresentative sub-set of susceotible locations.
Monitori.nmaynberacteal for RIVER LEN B 3.5- e. visionqa No.r RIVER BEND B 3.5-9 Revision No. 0 RBG-47497 Attachment 3 Page 9 of 25 ECCS-Operating B 3.5,1 BASES (continued) locations that are inaccessible due to radioloocai or environmental conditions, the plant confiquranqgor personnel safety. For these locations alternative methods (e.q.. operating parameters, remote monitoring) may beused to monitor the susceptible location.
Monitorng is not required for susceptible locations where the maximum potential accumulated oas void volume has been evaluated and determined to not challenge system OPERABILITY.
The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.The 31 day Frequency is based on operating experience, on the procedural controls governing system operation, and on the gradual nature of void buildup in the ECCS piping.SR 3.5.1.2 Verifying the correct alignment for manual, power operated, and automatic valves in the ECCS flow paths provides assurance that the proper flow paths will exist for ECCS operation.
This SR does not apply to valves that are locked, sealed, or otherwise secured in position since these valves were verified to be in the correct position prior to locking, sealing, or securing.
A valve that receives an initiation signal is allowed to be in a nonaccident position provided the valve will automatically reposition in the proper stroke time. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves potentially capable of being mispositioned are in the correct position.
This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.The 31 day Frequency of this SR was derived from the Inservice Testing Program requirements for performing valve testing at least once every 92 days. The Frequency of 31 days is further justified because the valves are operated under procedural control and because improper valve alignment would only affect a single subsystem.
This Frequency has been shown to be acceptable through operating experience.(continued)
RIVER SEND B 3.5-.9 Revision No. O RBG-47497 Attachment 3 Page 10 of 25 ECCS-Operating B3.5.1 BASES SURVEILLANCE SR 3.5.1.2 (continued)
REQUIREMENTS This SR is modified by a-Note 1 that allows LPCI subsystems to be considered OPERABLE during alignment and operation for decay heat removal with reactor steam dome pressure less than the RHR cut in permissive pressure in MODE 3, if capable of being manually realigned (remote or local) to the LPCI mode and not otherwise inoperable.
This allows operation in the RHR shutdown cooling mode during MODE 3 if necessary.
This SR is also modified bv Note 2 which exemots system vent flow paths opened under administrative control. The administrative control should be proceduralized and include stationing a dedicated individual at the system vent flow path who is in continuous communication with the operators in the controi room. This individual wil! have a method to rapidly close the system vent flow path if directed.SR 3.5.1.3 Verification every 31 days that ADS air accumulator supply pressure is> 131 psig assures adequate air pressure for reliable ADS operation.
The accumulator on each ADS valve provides pneumatic pressure for valve actuation.
The designed pneumatic supply pressure requirements for the accumulator are such that, following a failure of the pneumatic supply to the accumulator, at least two valve actuations can occur with the drywell at 70% of design pressure (Ref. 13). The ECCS safety analysis assumes only one actuation to achieve the depressurization required for operation of the low pressure ECCS. This minimum required pressure of 131 psig is provided by the nonsafety related air supply system (SVV) with safety related backup from the penetration valve leakage control system (LSV), post LOCA, at a system design pressure of 120 psig. The 31 day Frequency takes into consideration administrative control over operation of the SVV and LSV Systems and alarms for low air pressure.SR 3.5.1.4 The performance requirements of the ECCS pumps are determined through application of the 10 CFR 50, Appendix K, criteria (Ref. 8). This periodic Surveillance is performed (in accordance with the ASME OM Code requirements for the ECCS pumps) to verify that the ECCS pumps will develop the flow rates required by the respective analyses.
The ECCS pump flow rates ensure that adequate core cooling is provided to satisfy the acceptance criteria of 10 CFR 50.46 (Ref. 10).(continued)
RIVER BEND B 3.5-10 Revision No. 140 RBG-47497 Attachment 3 Page 11 of 25 ECCS-Shutdown B 3.5.2 B 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) AND REACTOR CORE ISOLATION COOLING (RCIC) SYSTEM B 3.5.2 ECCS--Shutdown BASES BACKGROUND A description of the High Pressure Core Spray (HPCS) System, Low Pressure Core Spray (LPCS) System, and low pressure coolant injection (LPCI) mode of the Residual Heat Removal (RHR) System is provided in the Bases for LCO 3.5.1, "ECCS-Operating." APPLICABLE SAFETY ANALYSES ECCS performance is evaluated for the entire spectrum of break sizes for a postulated loss of coolant accident (LOCA). The long term cooling analysis following a design basis LOCA (Ref. 1) demonstrates that only one ECCS injection/spray subsystem is required, post LOCA, to maintain the peak cladding temperature below the allowable limit. It is reasonable to assume, based on engineering judgement, that while in MODES 4 and 5, one ECCS injection/spray subsystem can maintain adequate reactor vessel water level. To provide redundancy, a minimum of two ECCS subsystems are required to be OPERABLE in MODES 4 and 5.The ECCS satisfy Criterion 3 of the NRC Policy Statement.
LCO Two ECCS injection/spray subsystems are required to be OPERABLE.The ECCS injection/spray subsystems are defined as the three LPCI subsystems, the LPCS System, and the HPCS System. The LPCS System and each LPCI subsystem consist of one motor driven pump, piping, and valves to transfer water from the suppression pool to the RPV. The HPCS System consists of one motor driven pump, piping, and valves to transfer water from the suppression pool or condensate storage tank (CST) to the RPV. Management of gas voids is important to ECCS iniection/spray subsystem OPERABILITY.
One LPCI subsystem (A or B) may be aligned for decay heat removal in MODE 4 or 5 and considered OPERABLE for the ECCS function, if it can be manually realigned (remote or local) to the LPCI mode and is not otherwise inoperable.
Because of low pressure and low temperature conditions in MODES 4 (continued)
RIVER BEND B 3.5-15 Revision No. 0 RBG-47497 Attachment 3 Page 12 of 25 ECCS-Shutdown B 3.5.2 BASES SURVEILLANCE SR 3.5.2.3. SR 3.5.2.5, and SR 3.5.2.6 REQUIREMENTS (continued)
The Bases provided for SR 3.5.1.1, SR 3.5.1.4, and SR 3.5.1.5 are applicable to SR 3.5.2.3, SR 3.5.2.5, and SR 3.5;2.6. respectively.
SR 3.5.2.4 Verifying the correct alignment for manual, power operated, and automatic valves in the ECCS flow paths provides assurance that the proper flow paths will exist for ECCS operation.
This SR does not apply to valves that are locked, sealed, or otherwise secured in position since these valves were verified to be in the correct position prior to locking, sealing, or securing.
A valve that receives an initiation signal is allowed to be in a nonaccident position provided the valve will automatically reposition in the proper stroke time. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of potentially being mispositioned are in the correct position.
This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves. The 31 day Frequency is appropriate because the valves are operated under procedural control and the probability of their being mispositioned during this time period is low.In MODES 4 and 5, the RHR System may operate in the shutdown cooling mode to remove decay heat and sensible heat from the reactor.Therefore, RHR valves that are required for LPCI subsystem operation may be aligned for decay heat removal. This SR is modified by a Note that allows one LPCI subsystem of the RHR System to be considered OPERABLE for the ECCS function if all the required valves in the LPCI flow path can be manually realigned (remote or local) to allow injection into the RPV and the system is not otherwise inoperable.
This will ensure adequate core cooling if an inadvertent vessel draindown should occur, The Surveillance is modified by a Note which exempts system vent flow pathsened under administraive control. The administrative control should be oroceduraiized and include stationinga dedicated individual at the system vent flq~wjath who is in continuous communication with the operato,-s in: the control room. This individual wiil have a method to rapidiv ciose the system vent flow oath if directed.REFERENCES
- 1. USAR, Section 6.3.3.4.RIVER BEND B 3.5-1g Revision No. 0 RBG-47497 Attachment 3 Page 13 of 25 RCIC System B 3.5.3 BASES BACKGROUND (continued)
The RCIC pump is provided with a minimum flow, bypass line which discharges to the suppression pool. The valve in this line automatically opens to prevent pump damage due to overheating when other discharge line valves are closed. To ensure rapid delivery of water to the RPV and to minimize water hammer effects, the RCIC System discharge line "keep fill" system is designed to maintain the pump discharge line filled with water.APPLICABLE SAFETY ANALYSES The function of the RCIC system is to respond to transient events by providing makeup coolant to the reactor. The RCIC system is not an Engineered Safety Feature system, and the safety analysis does not consider RCIC to be a system needed to mitigate the consequences of a control rod drop accident.
Based on its contribution to the reduction of overall plant risk, however, the system is included in the Technical Specifications as required by the NRC Policy Statement.
LCO The OPERABILITY of the RCIC System provides adequate core cooling such that actuation of any of the ECCS subsystems is not required in the event of RPV isolation accompanied by a loss of feedwater flow. The RCiC System has sufficient capacity to maintain RPV inventory during an isolation event. Management of gas voids is important to RCIC system OPERABILITY.
APPLICABILITY The RCIC System is required to be OPERABLE in MODE 1, and MODES 2 and 3 with reactor steam dome pressure > 150 psig since RCIC is the primary non-ECCS water source for core cooling when the reactor is isolated and pressurized.
In MODES 2 and 3 with reactor steam dome pressure < 150 psig, and in MODES 4 and 5, RCIC is not required to be OPERABLE since the ECCS injection/spray subsystems can provide sufficient flow to the vessel.ACTIONS A Note prohibits the application of L.CO 3.0.4.b to an inoperable RCIC system. There is an increased risk associated with entering a MODE or other specified condition in the Applicability with an inoperable RCIC system and the provisions of LCO 3.0.4.b, which allow entry into a MODE or other specified condition in the Applicability with the LCO not met after performance of a risk assessment addressing inoperable systems and components, should not be applied in this circumstance.(continued)
RIVER BEND B 3.5-21 Revision No. 133 RBG-47497 Attachment 3 Page 14 of 25 RCIC System B 3.5.3 BASES (continued)
SURVEILLANCE SR 3.5.3.1 REQUIREMENTS q-h fw " eea va" s enteainod air. Maintainipq the um discha4:qo
~ina.**;Of-1/2R-CA-Syteff 44itpe -4he ÷ ;;GGF This w;!alse hmer- '.oig " ii-tn-iatinsgn.
T-ha Sle --t nt at, the high points.The RCIC System flow oath pioing and components have the potential to develop voids and oockets of entrained .ases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RCIC System and may also prevent a water hammer.gump cavitation, and pumpina of noncondensibte gas.Selection of RCiC System locations susceptible to gas accumulation is based on a self-assessment of the piping confiouration to identify where gases may accumulate and remain even'after the system is filied and vented, and to identify vulnerable potential degassing flow paths. The review is supplemented by verification that installed high-point vents are actually at the system high points, incl;uding field verification to ensure pine shapes and construction tolerances have not inadvertently created additional high voints. Susceptible locations depend on plant and system confiQuration, such as stand-by versus operating conditions.
The RCIC System is OPERABLE when it is sufficiently filed with water.Acceptance criteria are established for the volume of accumulated gas at susceptible locations.
If accumulated e.as is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated cas at one or more susceptible locations exceeds an acgceptance criteria for as volume at the suction or discharge of a pumr,). the Surveillance is not met. if it is determined by subsequent evaluation that the RCIC Systems are not rendered inoperable by the accumulated gas (.e... the system is sufficiently filled with waterO the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.RCCSysem to gas accumulation are monmtored and, if gas is cornred to the acceptance criteria for the location.
Susceptible locations in the same system flow oath which are subject to the same gas intrusion mechanisms may be verified by monitorig a representative sub-set of susce.tib!e iocations.
Monitoing may not be practical for locations that are inaccessible due to radiological or environmental conditions.
the pjlant q2iuradior, or personneletv .o,.heseiocatonsatarrative methods .oqqper.tina
.
remote be used to monitor the B 3.5-23 Revision No. 0 RIVER BEND RBG-47497 Attachment 3 Page 15 of 25 RCIC System B 3.5.3 BASES (continued) susceptible location.
Monitoring is not required for susceptible locations where the maximum Potential accumulated gas void volume has been evaluated and determined to not chal!enae system OPERABILITY.
The accuracy of the method used for monitoring the susceotible locations and trending of the results should be sufficient to assure system OPERABILITY during_ the Surveillance interval.The 31 day Frequency is based on the gradual nature of void buildup in the RCIC piping, the procedural controls governing system operation, and operating experience.
SR 3.5.3.2 Verifying the correct alignment for manual, power operated, and automatic valves in the RCIC flow path provides assurance that the proper flow path will exist for RCIC operation.
This SR does not apply to valves that are locked, sealed, or otherwise secured in position since these were verified to be in the correct position prior to locking, sealing, or securing.
A valve that receives an initiation signal is allowed to be in a nonaccident position provided the valve will automatically reposition in the proper stroke time. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of potentially being mispositioned are in the correct position.
This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves. For the RCIC System, this SR also includes the steam flow path for the turbine and the flow controller position.The 31 day Frequency of this SR was derived from the Inservice Testing Program requirements for performing valve testing at least every 92 days. The Frequency of 31 days is further justified because the valves are operated under procedural control and because improper valve position would affect only the RCIC System. This Frequency has been shown to be acceptable through operating experience.
The Surveillance is modified by a Note which exem tsits syistem vent flow Daths opened under administrative control. The administrative control should beqeroceduraLized and include stationing a dedicated individual at the system vent flow oath who is in continuous communication with the in the control room. This individual wi~l have a method to.rWpiIdclose.
t he sstern vent flow ath if directed.(continued)
RIVER BEND 8 3.5-23 Revision No, 0 RBG-47497 Attachment 3 Page 16 of 25 RHR Suppression Pool Cooling B 3.6.2.3 BASES APPLICABLE SAFETY ANALYSES (continued)
The RHR Suppression Pool Cooling System satisfies Criterion 3 of the NRC Policy Statement.
LCO During a DBA, a minimum of one RHR suppression pool cooling subsystem is required to maintain the primary containment peak pressure and temperature below the design limits (Ref. 1). To ensure that these requirements are met, two RHR suppression pool cooling subsystems must be OPERABLE.
Therefore, in the event of an accident, at least one subsystem is OPERABLE, assuming the worst case single active failure.An RHR suppression pool cooling subsystem is OPERABLE when the pump, two heat exchangers, and associated piping, valves, instrumentation, and controls are OPERABLE.
Management of gas voids is imoortant to RHR Suppression Pool Cooling System OPERABULITY.
APPLICABILITY In MODES 1, 2, and 3, a DBA could cause a release of radioactive material to primary containment and cause a heatup and pressurization of primary containment.
In MODES 4 and 5, the probability and consequences of these events are reduced due to the pressure and temperature limitations in these MODES. Therefore, the RHR Suppression Pool Cooling System is not required to be OPERABLE in MODE 4 or 5.ACTIONS A.1_With one RHR suppression pool cooling subsystem inoperable, the inoperable subsystem must be restored to OPERABLE status within 7 days. in this Condition, the remaining RHR suppression pool cooling subsystem is adequate to perform the primary containment cooling function.
However, the overall reliability is reduced because a single failure in the OPERABLE subsystem could result in reduced primary containment cooling capabiliby.
The 7 day Completion Time is acceptable in light of the redundant RHR suppression pool cooling capabilities afforded by the OPERABLE subsystem and the low probability of a DBA occurring during this period.(continued)
RIVER BEND B 3.6-63 Revision No. 0 RBG-47497 Attachment 3 Page 17 of 25 RHR Suppression Pool Cooling B 3.6.2.3 BASES ACTIONS B..1 (continued)
With two RHR suppression pool cooling subsystems inoperable, one subsystem must be restored to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. In this condition, there is a substantial loss of the primary containment pressure and temperature mitigation function.
The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Completion Time is based on this loss of function and is considered acceptable due to the low probability of a DBA and the potential avoidance of a plant shutdown transient that could result in the need of the RHR suppression pool cooling subsystems to operate.C. ? and C.2 If the Required Action and required Completion Time of Condition A cannot be met or if two RHR suppression pool cooling subsystems are inoperable, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to at least MODE 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and to MODE 4 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.SURVEILLANCE SR 3.6.2.3.1 REQUIREMENTS Verifying the correct alignment for manual, power operated, and automatic valves, in the RHR suppression pool cooling mode flow path provides assurance that the proper flow path exists for system operation.
This SR does not apply to valves that are locked, sealed, or otherwise secured in position since these valves were verified to be in the correct position prior to being locked, sealed, or secured. A valve is also allowed to be in the nonaccident position, provided it can be aligned to the accident position within the time assumed in the accident analysis.
This is acceptable, since the RHR suppression pool cooling mode is manually initiated.
This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of being mispositioned are in the correct position.
This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.The Frequency of 31 days is justified because the valves are operated under procedural control, improper valve position would affect only a single subsystem, the probability of an event requiring initiation of the system is low, and the subsystem is a manually initiated system. This Frequency has been shown to be acceptable, based on operating experience.
SR 3.6.2.3.2 RHR Suprpession Pool Cootina SystpmLt e arnd conlorients have the ocotentiai to develon vcids and oocets of entrained oases. Preventinq and RIVER BEND B 3.6-64 Revision No. 139 RBG-47497 Attachment 3 Page 18 of 25 RHR Suppression Pool Cooling B 3.6.2.3 BASES managing gas intrusion and accumulation is necessary for proper operation of the RHR suppression pool cooling subsystems and may also prevent water hammer and pump cavitation.
Selection of RHR Suppression Pool Cooling System locations susceptible to gas accumulation is based on a review of system design information.
including piping and instrumentation drawings, isometric drawings., plan and elevation drawings, and calculations.
The desion review is suopplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become surces of gas or could otherwise cause -gas to be trapped or difficult to remove during system maintenance or restoration.
Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.
The RHR Suppression Pool Cooling System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations.
If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceotance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subseauent evaluation that the RHR Suppression Pool Cooling System is not rendered inoperable by the accumulated Qas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met.Accumulated gas should be eliminated or. brought within the acceotance critera limits.RHR Suppression Pool Cooling System locations susceptible to gas accumulation are monitored and, if clas is found., the gas volume is compared to the acceptance criteda for tfhe location.
Susceptible locations in the same system flow path which are subiect to the same gas intrusion mechanisms may be verified by monitorinq a representative sub-set of susceptible locations.
Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.
Monitorino is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY.
The accuracy of 'he method used for monitoring the susceptible locations and trending of the results should be sufficient to assure-system OPERABILITY during the Surveillance interval.The 31 day Frequency takes into consideration the gradua! nature of Gas accumulation in the RHR Suppression Pobi Cooiing, Svstemr piping and the procedural controls governing..system operation.(continued)
RIVER SEND 6 3.6-64 Revision No. 139 RBG-47497 Attachment 3 Page 19 of 25 RHR Suppression Pool Cooling B 3.6.2.3 BASES SURVEILLANCE SR 3.6.2.3.23 REQUIREMENTS (continued)
Verifying each RHR pump develops a flow rate -5050 gpm, with flow through the associated heat exchanger to the suppression pool ensures that pump performance has not degraded during the cycle. Flow is a normal test of centrifugal pump performance required by ASME OM Code (Ref. 2). This test confirms one point on the pump design curve, and the results are indicative of overall performance.
Such inservice inspections confirm component OPERABILITY, trend performance, and detect incipient failures by indicating abnormal performance.
The Frequency of this SR is in accordance with the Inservice Testing Program.REFERENCES
- 1. USAR, Section 6.2.2. ASME Code for Operation and Maintenance of Nuclear Power Plants.RIVER BEND B 3,6-651 Revision No. 140 RBG-47497 Attachment 3 Page 20 of 25 RHR -- High Water Level B 3.9.8 BASES LCO (continued)
I An OPERABLE RHR shutdown cooling subsystem consists of an RHR pump, two heat exchangers, valves, piping, instruments, and controls to ensure an OPERABLE flow path. Management of gas voids is important to RHR Shutdown Cooling System OPERABILITY.
Additionally, each RHR shutdown cooling subsystem is considered OPERABLE if it can be manually aligned (remote or local) in the shutdown cooling mode for removal of decay heat. Operation (either continuous or intermittent) of one subsystem can maintain and reduce the reactor coolant temperature as required.
However, to ensure adequate core flow to allow for accurate average reactor coolant temperature monitoring, nearly continuous operation is required.
A Note is provided to allow a 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> exception to shut down the operating subsystem every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.APPLICABILITY One RHR shutdown cooling subsystem must be OPERABLE in MODE 5, with irradiated fuel in the RPV and the water level _> 23 ft above the top of the RPV flange, to provide decay heat removal. RHR System requirements in other MODES are covered by LCOs in Section 3.4, Reactor Coolant System (RCS); Section 3.5, Emergency Core Cooling Systems (ECCS) and Reactor Core Isolation Cooling (RCIC) System; and Section 3.6, Containment Systems. RHR Shutdown Cooling System requirements in MODE 5, with the water level < 23 ft above the RPV flange, are given in LCO 3.9.9, "Residual Heat Removal (RHR) -Low Water Level.ACTIONS A. 1 With no RHR shutdown cooling subsystem OPERABLE, an alternate method of decay heat removal must be established within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. In this condition, the volume of water above the RPV flange provides adequate capability to remove decay heat from the reactor core. However, the overall reliability is reduced because loss of water level could result in reduced decay heat removal capability.
The 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Completion Time is based on the decay heat removal function and the probability of a loss of the available decay heat removal capabilities.
Furthermore, verification of the functional availability of these alternate method(s) must be reconfirmed every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> thereafter.
This will ensure continued heat removal capability.(continued)
RIVER BEND B 3.9-26 Revision No. 0 RBG-47497 Attachment 3 Page 21 of 25 RHR -High Water Level B 3.9.8 BASES SURVEILLANCE SR 3.9.8.1 REQUIREMENTS This Surveillance demonstrates that the RHR shutdown cooling subsystem is in operation and circulating reactor coolant. The required flow rate is determined by the flow rate necessary to provide sufficient decay heat removal capability.
The Frequency of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is sufficient in view of other visual and audible indications available to.the operator for monitoring the RHR subsystem in the control room.SR 3.9.8.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and POckets of entrained gases. Preventing and manaaingaas intrusion and accumulation is necessary for proper operation of the required RHR shutdown cooling subsystem(s) and may also prevent water hammer, pump cavitation, and pumoinq of noncondensible gas into the reactor vessel.Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a.review of system design information, includinq giping and instrumentation d.rawins, isometric drawings, plan and elevation drawings, and calculations.
The design review is supplemented bV system walk downs to validate the system-high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause -gas to be trapped or difficult to remove during system maintenance or restoration.
Susceptible locations depend on plant and system confiquration, such as stand-by versus operating conditions.
The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations.
If accumulated gqs is discovered that exceeds the acceptance criteria for the suscep~tible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a PumP).the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e_, the system is sufficiently filled with water). the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.RHR Shutdown Cooling System locations susceptible to gas accumula tigon are monitored and, if .as is found. the as volume is comoared to the acceptance criteria for the location.
Suscepti le locations in the same svstem flow path which are subiect to the same gas intrusion mechanisms may be verified by monitoring a representative sub-set of susceptible locations.
Monitoring may not be practical for locations that are inaccessible du to radioaogical or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.q., operating parameters.
remote monitoring) may be.used to mDonitor the susceptible location.
Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY.
The accuracv of the method used for monitoring the susceptible locations and trending of the results shouid be sufficient to assure system ILEIY during the Sur v.92eilla nee ;Interval.
RIVER BEND B 3.9-28a Revision No. 4-2 RBG-47497 Attachment 3 Page 22 of 25 RHR -High Water Level B 3.9.8 The 31 day Frequency takes into consideration the pradual nature of cas accumulation in the RHR Shutdown Cooing Svstem pjpi_ g and the 2rocedural controls governing system operation.
REFERENCES None.RIVER BEND B 3.9-28a R B evision No. 4-2 RBG-47497 Attachment 3 Page 23 of 25 RHR-Low Water Level B 3.9.9 B 3.9 REFUELING OPERATIONS B 3.9.9 Residual Heat Removal (RHR)-Low Water Level BASES BACKGROUND The purpose of the RHR System in MODE 5 is to remove decay heat and sensible heat from the reactor coolant, as required by GDC 34. Each of the two shutdown cooling loops of the RHR System can provide the required decay heat removal. Each loop consists of one motor driven pump, two heat exchangers, and associated piping and valves. Both loops have a common suction from the same recirculation loop. Each pump discharges the reactor coolant, after it has been cooled by circulation through the respective heat exchangers, to the reactor via separate feedwater lines, to the upper containment pool via a common single flow distribution sparger, or to the reactor via the low pressure coolant injection path. The RHR heat exchangers transfer heat to the normal or Standby Service Water System. The RHR shutdown cooling mode is manually controlled.
APPLICABLE With the unit in MODE 5, the RHR System is not required to mitigate any SAFETY ANALYSES events or accidents evaluated in the safety analyses.
The RHR System is required for removing decay heat to maintain the temperature of the reactor coolant.Although the RHR System does not meet a specific criterion of the NRC Policy Statement, it was identified in the NRC Policy Statement as an important contributor to risk reduction.
Therefore, the RHR System is retained as a Specification.
LCO In MODE 5 with irradiated fuel in the reactor pressure vessel (RPV) and the water level < 23 ft above the RPV flange both RHR shutdown cooling subsystems must be OPERABLE.An OPERABLE RHR shutdown cooling subsystem consists of an RHR pump, two heat exchangers, valves, piping, instruments, and controls to ensure an OPERABLE flow path. Management of gas voids is important to RHR Shutdown Cooring__System OPERABILITY (continued)
RIVER BEND B 3.9-29 Revision No. 0 RBG-47497 Attachment 3 Page 24 of 25 RHR -Low Water Level B 3.9.9 BASES ACTIONS C.1 and C.2 (continued) out of service, and normal decay heat removal systems are lost or intentionally turned off, especially during periods of high decay heat load.SURVEILLANCE SR 3.9.9.1 REQUIREMENTS This Surveillance demonstrates that one RHR shutdown cooling subsystem is in operation and circulating reactor coolant. The required flow rate is determined by the flow rate necessary to provide sufficient decay heat removal capability.
The Frequency of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is sufficient in view of other visual and audible indications available to the operator for monitoring the RHR subsystem in the control room.SR 3.9.9.2 RHR Shutdown Coolingq System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managin~ gas intrusion and accumulation is necessary for proper operation of the, RHR shutdown cooling subsystems and may also prevent water hammer, pump cavitation, and pumoino of noncondensible gas into the reactor vessel.Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system .desiQn information, including pioino and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations, The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration.
Susceptible locations deoend on plant and system configuration, such as stand-by versus operatingI conditions.
The RHR Shutdown Cooling System is OPERABLE when it is sufficientil filled with water. Acceotance criteria are established for the volume of accumulated gas at susceptible locations.
If accumulated aas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceotance criteria for qas volume at the suction or dischar eg oef. a pump), the Surveillance is riot met. if it is determined bb subseguent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated -gas 7'e.. the systemjis sufficiently filted with water). the Surveillance may be decIared mret. Accumuiated .as should be eliminated or brought within the acceptance criteria iimits.RHR Shutdown Coolinc System locations susce:tible to .as accumuiation are monitored and, if aas is found, the gas voiume is comoared to the acceptance criteria for the location.
Susceptitte locations in the same system flow path which are subiect to the same gas intrusion mechanisms m be verified by monitoring a representative sub-set ,f susceptible locations.
Monitoring may not be practical for locations that are inaccessible due. to radiofogica1_or environmental conditions, the plant configuration.
or personnel safeb.,For these locations alternative methods parameters, remote monitormn, abe. .used to monitor RIVER BEND B 3.9-32a Revision No. 4-2 RBG-47497 Attachment 3 Page 25 of 25 RHR -Low Water Level B 3.9.9 BASES the susce)tible location.
Monitorng is not reauired for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY.
The accuracv of the method used for monitoring the suscectible locations and trending of the results should be sufficient to assure system OPERABILITY durinq the Surveillance interval.The 31 day Frequency takes into consideration the gradual nature of gas accumulation in the RHR Shutdown Cooling System piping and the procedural controls ..governing system ooeration.
REFERENCES None.RIVER SEND B 3.9-32a Revision No. 4-2 Attachment 4 RBG-46497 List of Regulatory Commitments RBG-47497 Attachment
,4 Page 1 of 1 List of Regulatory Commitments The following table identifies those actions committed to by Entergy in this document.
Any other statements in this submittal are provided for information purposes and are not considered to be regulatory commitments.
TYPE SCHEDULED COMMITMENT ONE-TIME CONTINUING COMPLETION ACTION COMPLIANCE DATE Corresponding BASES for each affected X Upon RBS TS will be modified consistent with the Implementation approved TSTF.For the RHR Shutdown Cooling System, TS X Startup RF-19 3.4.9 and 3.4.10, the required venting locations will be determined prior to startup from refueling outage (RF) 19 currently scheduled for early 2017.