ML18095A857
| ML18095A857 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 03/28/1991 |
| From: | Crimmins T Public Service Enterprise Group |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| RTR-REGGD-01.155, RTR-REGGD-1.155 NLR-N91047, NUDOCS 9104090255 | |
| Download: ML18095A857 (25) | |
Text
Public Service Electric and Gas Company Thomas M. Crimmins, Jr.
Public Service Electric and Gas Company P.O. Box 236, Hancocks Bridge, NJ 08038 609-339-4700 Vice President - Nuclear Engineering MAR 2 8 1QQ1 NLR-N91047 United Sates Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Gentlemen:
STATION BLACKOUT REVISED COPING ANALYSIS SALEM GENERATING STATION UNITS 1 AND 2 DOCKET NOS. 50-272 AND 50-311 Public Service Electric and Gas (PSE&G) hereby submits the results of the coping category determination and the revised coping analysis study performed for Salem Generating Station Units 1 and 2 in response to the requirements of 10 CFR 50.63.
This coping analysis was performed in accordance with the guidance provided in USNRC Regulatory Guide 1.155, NUMARC 87-00, "Guidelines and Technical Bases for NUMARC Initiatives Addressing Station Blackout at Light Water Reactors," and NUMARC letter, "Station Blackout (SBO) Implementation: Request for Supplemental SBO Submittal to NRC," dated January 4, 1990, in order to comply with the requirements of 10 CFR 50.63.
Based on the revised coping analysis, Salem Generating Station Units 1 and 2 require a modification to the compressed air system in order to cope with the SBO event for the required coping duration, as calculated by NUMARC 87-00 methodologies.
Due to the financial magnitude of this modification, the change to the compressed air system requires approval by the Co-Owners of the Salem Generating Station and approval in accordance with our Corporate proj ec.t authorization procedure before the modification can be implemented.
We do not anticipate these approvals to impede the implementation schedule that will be established once we receive the NRC Safety Evaluation Report for the station Blackout coping analysis.
PSE&G would like to extend an offer to present our SBO coping analysis to the NRC Staff at your offices.
It is our belief that this meeting would facilitate the review of our coping analysis, by the staff, and provide a forum to address any questions or concerns raised by this review.
(
9104090255 OjO~?g PDR ADOCK 6~665~72 P
Document Control Desk NLR-N91047 2
MAR 2 8 19QT Please do not hesitate to contact us if you have any questions regarding this submittal.
Sincerely, Attachment
Document Control Desk NLR-N91047 c
Mr. J. c. Stone Licensing Project Manager Mr. T. Johnson Senior Resident Inspector Mr. T. Martin, Administrator Region I Mr. Kent Tosch, Chief 3
New Jersey Department of Environmental Protection Division of Environmental Quality Bureau of Nuclear Engineering CN 415 Trenton, NJ 08625 MAR 2*-s 1gg1
f SECTION
- 1. 0 2.0 2.1 2.2 3.0 3.1 3.1.1 3.1. 2 3.1. 3 3.1.4 3.1.5 4.0 4.1 4.2 5.0 6.0 ATTACHMENT TO NLR-N91047 TABLE OF CONTENTS DESCRIPTION EXECUTIVE
SUMMARY
GENERAL CRITERIA AND BASELINE ASSUMPTIONS GENERAL CRITERIA BASELINE ASSUMPTIONS REQUIRED COPING DURATION CATEGORY COPING DURATION CALCULATION OFF-SITE POWER DESIGN CHARACTERISTIC GROUP EMERGENCY AC POWER CONFIGURATION GROUP CALCULATED EOG RELIABILITY ALLOWED EOG TARGET RELIABILITY COPING DURATION CATEGORY STATION BLACKOUT RESPONSE PROCEDURES PROCEDURES TRAINING COLD STARTS EMERGENCY AC POWER AVAILABILITY 1
3 4
4 4
5 5
5 5
5 5
6 7
7 7
8 9
SECTION DESCRIPTION PAGE 7.0 COPING WITH A STATION 10 BLACKOUT EVENT 7.1 OVERVIEW 10 7.1.1 COPING METHODOLOGY 10 7.1.2 COPING DURATION 10 7.2 COPING ASSESSMENT 11 7.2.1 CONDENSATE INVENTORY 11 7.2.2 CLASS lE BATTERY CAPACITY 13 7.2.3 COMPRESSED AIR 16 7.2.4 EFFECTS OF LOSS OF 21 VENTILATION 7.2.5 CONTAINMENT ISOLATION 22 2
1.0 EXECUTIVE
SUMMARY
Code of Federal Regulations 10 CFR Part 50.63, Loss of all Alternate Current Power, requires that "Each light water-cooled nuclear power plant licensed to operate must be able to withstand for a specified duration and recover from a station blackout *** ".
The guidelines for complying with this regulation are provided in USNRC Regulatory Guide (RG)l.155, dated August 1988, and Nuclear Management and Resources Council NUMARC document 87-00, dated November 1987.
A Station Blackout (SBO) Analysis for Salem Generating Station ~ Units 1 and 2 has been performed in accordance with the guidelines provided in RG 1.155 and NUMARC 87-00 for assessment of its compliance with the requirements of Federal Regulation 10 CFR 50.63.
The assessment used the "AC-Independent" approach outlined in NUMARC 87-00 for its coping capability.
In this approach, plants rely on available process steam, de power and compressed air to operate equipment necessary to achieve and maintain hot shutdown.
The required SBO coping duration for Salem Generating Station is calculated as 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> in accordance with the methods provided in NUMARC 87-00.
The analysis establishes that: 1) adequate condensate inventory will be available for decay heat removal, 2) the plant class lE batteries have adequate capacity to supply all SBO de and inverter loads for four hours with minimal manual load stripping, 3) SBO equipment operability will be maintained at the elevated room temperatures caused by loss of ventilation, 4) containment isolation capability will be maintained to ensure containment integrity, and 5) the plant compressed air system will require modification to be able to provide adequate compressed air needed to cope with the SBO.
These results provide adequate assurance that Salem Generating Station Units 1 and 2 shall be able to withstand and recover from a station blackout event for a coping duration of four hours.
The plant Emergency Operating Procedures (EOPs) and other related plant procedures will be revised as required to include the results of this analysis.
Appropriate plant personnel will be trained in the revised/new plant procedures.
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1' 2.0 2.1 GENERAL CRITERIA AND BASELINE ASSUMPTIONS GENERAL CRITERIA The general criteria for Station Blackout Coping provided in NUMARC 87-00, Section 2.1 has been used for Salem Generating Station - Units 1 and 2 Station Blackout (SBO) coping and recovery analysis.
This states that:
"Procedures and equipment in light water reactors relied upon in a station blackout should ensure that satisfactory performance of necessary decay heat removal systems is maintained for the required station blackout coping duration.
For a PWR, an additional requirement is to keep the core covered.
For a BWR, no more than a momentary core uncovery is allowed.
For both BWRs and PWRs, appropriate containment integrity should also be provided in a station blackout to the extent that isolation valves perform their intended function without ac power."
2.2 BASELINE ASSUMPTIONS NUMARC 87-00 baseline assumptions pertaining to each of the following areas provided in Section 2.2 through 2.11 have been evaluated for their applicability to Salem Generating Station - Units 1 and 2.
Initial Plant Conditions Initiating Event Station Blackout Transient Reactor Coolant Inventory Loss Operator Action Effects of Loss of Ventilation System Cross-tie Capability Instrumentation and Controls Containment Isolation Hurricane Preparations These assumptions are applicable to Salem Generating Station (SGS) except for Hurricane Preparations.
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3.0 REQUIRED COPING DURATION CATEGORY 3.1 3.1.1 3.1.2 3.1.3 3.1.4 Salem Generating Station - Units 1 and 2 coping duration is determined as per the methodology provided in NUMARC 87-00, Section 3.2.
COPING DURATION CALCULATION Off-Site Power Design Characteristic Group (P Group)
Site Specific Evaluation ( Ref. NUS-5175 "Estimated Frequency of Loss of Off-Site Power Due to Extremely Severe Weather (ESW) and Severe Weather (SW) for Salem and Hope Creek Generating Stations") places the plant in ESW group 2 and SW group 2.
The offsite power system falls in the Il/2 group.
ESW group 2, SW group 2 and Il/2 group places the plant in Offsite AC Power Design Characteristic Group Pl.
Emergency AC (EAC) Power Configuration Group (A, B, c or D Group)
Of the three dedicated EAC power supplies available for each unit at Salem Generating station, only two are necessary for safe shutdown in case of a design basis event.
As per NUMARC 87-00, Table 3-7, this corresponds to an EAC Power Configuration Group D.
Calculated EDG Reliability Based on the last 100 demands, Salem Generating Station
- Units 1 and 2 calculated EDG reliability is determined as 99% and 98.9% respectively.
Allowed EDG Target Reliability As established in Section 3.1.2, Salem Generating Station falls in EAC Power Configuration Group D.
Therefore, the EDG target reliability for Salem Generating Station is 0.975 as per NUMARC 87-00, Section 3.2.4.
This is allowable for Salem Generating Station - Units 1 and 2 since the calculated EDG reliability for these units are 0.99 and 0.989 respectively.
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3.1.5 Coping Duration Category Based on the Off-Site Power Group P1, EAC Group D and Allowed EDG Target Reliability of 0.975, Salem Generating Station - Units 1 and 2 falls in the Required Coping Duration Category of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> as per NUMARC 87-00, Table 3-8.
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4.0 STATION BLACKOUT RESPONSE PROCEDURES 4.1 PROCEDURES 4.2 Salem Generating Station - Units 1 and 2 Emergency Operating Procedures (EOPs) and other Plant Procedures shall be revised and new Plant Procedures shall be prepared as required to incorporate the results of the Station Blackout analysis.
Revisions and new procedures will be in accordance with NUMARC 87-00, Section 4.0.
TRAINING Appropriate plant personnel will be trained on new and revised Emergency Operating Procedures (EOPs) and other plant operating procedures.
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,/
5.0 COLD STARTS Salem Generating Station - Units 1 and 2 emergency diesel generators (EDGs) are provided with continuous pre-warmed circulating water and pre-lubrication features.
As defined in NUMARC 87-00, Section 5.1, emergency diesel generators with continuous pre-warmed and pre-lubed features are not considered to have cold starts.
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6.0 EMERGENCY AC POWER AVAILABILITY Salem Generating Station - Units 1 and 2 have established EOG reliability target levels consistent with the plant category and coping duration as explained in NUMARC 87-00, Section 3.2.4.
There are existing surveillance testing and performance monitoring procedures designed to track EOG performance and to support maintenance activities.
There are maintenance programs for the emergency diesel generators that provide capability for failure analysis and root-cause investigation.
These procedures and programs ensure that the selected reliability levels of the emergency diesel generators for Salem Generating Station - Units 1 and 2 are achieved and maintained.
9 l
- l 7.0 7.1 7.1.1 7.1.2 COPING WITH A STATION BLACKOUT EVENT OVERVIEW The SBO coping assessment has been performed in accordance with the procedures provided in NUMARC 87-00, Section 7.0.
This assessment addresses all five NUMARC 87-00 initiatives listed below:
- 1.
Condensate Inventory for Decay Heat Removal
- 2.
Assessing Class lE Battery Capacity
- 3.
Compressed Air
- 4.
Effects of Loss of Ventilation
- 5.
Containment Isolation Coping Methods SBO coping assessment of Salem Generating Station -
Units 1 and 2 is performed with the 'AC-Independent' approach.
In this approach, plants are assumed to rely on available process steam, de power and compressed air to operate equipment necessary to achieve and maintain hot shutdown conditions for four hours.
Coping Duration As described in Section 3.0, Salem Generating Station -
Units 1 and 2 must cope with a SBO for a duration of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
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J 7.2 7.2.1 7.2.1.1 COPING ASSESSMENT CONDENSATE INVENTORY The Condensate Inventory requirement for Decay Heat Removal (OHR) following a Station Blackout (SBC) event is evaluated as per the guidelines provided in NUMARC 87-00, Section 7.2.1.
Condensate Inventory Calculation The condensate inventory requirement (B) is calculated as follows:
B = A (22.12 Gal/MWt) + C
- Where, A = The **plant thermal rating
= 3,411 MWt c = 54,926 gal. (for Cooldown) + 38,490 gal. (for level shrinkage in Steam Generators)
= 93,416 gallons Therefore, B = 3,411 (22.12) + 93,416
= 168,867 gallons In addition to verifying the adequacy of condensate inventory by using NUMARC 87-00 equation as shown above, a reactor coolant inventory analysis has been performed in accordance with NUMARC 87-00*, Section 2. 5, using RETRAN and MAAP Computer Codes and Salem
'plant-specific models.
The required minimum usable Technical Spe~ificat.ion volume for auxiliary feedwater (condensa:f:",.:z,~ sto:i*a,ge
- tank (AFST) is 192,069 gallons compared to a calculated required volume of 168,867 gallons.
These thermal hydraulic transient analyses demonstrate that adequate reactor coolant inventory is maintained for a coping duration of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> and that the core stays covered.
Additional make-up systems are not required to ensure adequate core cooling. The decay 11
7.2.1.2 heat is transferred from the core to the Steam Generators by natural circulation/reflux condensation.
Conclusion On the basis of the above calculation, it is concluded that adequate condensate inventory is available for the decay heat removal including plant cooldown for a coping duration of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> following a station blackout event.
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7.2.2 7.2.2.1 CLASS lE BATTERY CAPACITY Methodology The capacity of the Salem Generating Station - Units 1 and 2 existing batteries to feed their connected SBO loads for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, was verified by calculating the battery capacity required for the SBO battery duty cycle as per IEEE Standard 485.
If the existing battery sizes equal or exceed these calculated SBO battery sizes, then the existing batteries are considered adequate for SBO.
NUMARC 87-00, Section 7.2.2 states that the station blackout loads on the battery can be estimated from design basis accident loads since they are generally a subset of these loads.
Salem Generating Station 125V and 28V DC Load Studies which identify the battery loads for the most severe plant design basis accident condition of coincident LOOP and LOCA have been used as the basis of determining the battery SBO duty cycle.
The duty cycle includes the ac power restoration loads at the most limiting time in the battery duty cycle.
In addition to calculating the battery capacity for SBO duty cycle, the battery terminal voltage profile, corresponding to the SBO duty cycle, is also calculated to verify that the minimum voltages r.eached during the duty cycle are higher than or equal to the minimum voltages required for operation of* the de loads.
The calculations for the SBO battery capacity use the lowest electrolyte temperature anticipated under plant normal operating conditions as required.by NUMARC 87-00.
The calculations for the SBO battery capacity use a Design Margin of 1.1 as recommended by IEEE standard 485 and as required by NUMARC 87-00.
An Aging Factor 1.25 has been used in calculating the SBO battery capacity as recommended by IEEE Standard 485 and as required by NUMARC 87-00.
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7.2.2.2 Calculation The results of the battery capacity evaluation for SBO is summarized as follows:
AVAILABLE EXCESS CAPACITY OVER BATTERY EXISTING REQUIRED SBO 1.1 DESIGN DESCRIPTION BATTERY SIZE BATTERY SIZE MARGIN 125V DC LCR-33 LCR-29 14.0%
Battery lA 125V DC LCR-33 LCR-27 23.0%
Battery lB 125V DC LC-33 LC-31 6.6%
Battery lC 125V DC LCR-33 LCR-29 14.0%
Battery 2A 125V DC LCR-33 LCR-25 33.3%
Battery 2B 125V DC LC-33 LC-29 14.0%
Battery 2C 28V DC KCR-21 KCR-17 25.0%
Battery lA 28V DC KCR-21 KCR-11 100.0%
Battery lB 28V DC KCR-21 KCR-17 25.0%
Battery 2A 28V DC KCR-21 KCR-13 66.0%
Battery 2B 125V DC Battery lC and 2C capacity evaluation include manual stripping of one non-essential load (Remote Shutdown Panel) on each battery after 30 minutes following the initiation of an SBO event.
This 30 minute period is adequate for performing these operations.
The related access routes and the equipment locations are provided with emergency battery pack lighting.
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7.2.2.3 The minimum battery terminal voltages reached during the battery SBO duty cycle ensure minimum required operating voltages at their connected load terminals.
These are 105 volts for 125V DC loads and 19.2 volts for 28V DC loads.
The results of the battery SBO capacity evaluation verifies that Salem Generating Station - Units 1 and 2 existing Class lE 125V DC and 28V DC batteries have adequate capacity to supply their connected SBO loads for the SBO coping duration of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> with the manual stripping of one non-essential load identified above.
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7.2.3 7.2.3.1 COMPRESSED AIR The capacity of compressed air system required for decay heat removal for 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> duration following a Station Blackout (SBO) event is evaluated as per the guidelines provided in NUMARC 87-00, Section 7.2.3.
Compressed Air Assessment The Salem Generating Station - Units 1 & 2 emergency control air system supply motive power for safety-related instrumentation, controls and equipment.
The system consists of two (2) redundant control air headers (one header is supplied from Unit 1, the other header from Unit 2), two (2) redundant 500 SCFM at 110 PSIG motor driven air compressors, two (2) dual tower heatless desiccant-type air dryers and associated support equipment.
The emergency control air system is a back-up system to the normal control air system and is automatically initiated whenever the control air header pressure is less than 85 psig, or, when started from the safeguard equipment control (SEC) panels.
The emergency control air system was designed with sufficient capacity to provide control air to the safety-related equipment and components for both Salem Units 1 & 2.
The control air system is redundantly designed such that Unit 1 and 2 emergency air headers are cross-connected to provide control air from either of the two emergency air compressors.
The station air compressors, which normally supply the control air headers are rendered inoperable as a result of the ac power loss.
As the control air header pressure degrades to 85 psig, the emergency air compressors attempt to start.
The failure of the emergency diesel generators to provide power to the vital buses prevents the EAC from restoring the control air header pressure. As the control air header depressurizes the air operated components used for decay heat removal move from the last control position to a failure position.
The loss of control air results in the following equipment status:
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FAILURE VALVE NO.
DESCRIPTION POSITION 11/21AF11 Auxiliary Feedwater Pump 13/23 OPEN Inlet to Steam Generator 11/21 12/22AF11 Auxiliary Feedwater Pump 13/23 OPEN Inlet to Steam Generator 12/22 13/23AF11 Auxiliary Feedwater Pump 13/23 OPEN Inlet to Steam Generator 13/23 14/24AF11 Auxiliary Feedwater Pump 13/23 OPEN Inlet to Steam Generator 14/24 1/2MS52 Auxiliary Feedwater Pump 13/23 OPEN Turbine Trip Valve 1/2MS132 Auxiliary Feedwater Pump OPEN Turbine 13/23 Start/Stop Valve ll/21MS10 steam Generator 11/21 CLOSE Atmospheric Relief Valve 12/22MS10 Steam Generator 12/22 CLOSE Atmospheric Relief Valve 13/23MS10 Steam Generator 13/23 CLOSE Atmospheric Relief Valve 14/24MS10 Steam Generator 14/24 CLOSE Atmospheric Relief Valve 17
7.2.3.2 The auxiliary feedwater pump turbine governor with its associated control valve is reverse acting and on loss of control air the turbine/pump will accelerate to the upper mechanical stop limit of 4000 RPM.
The loss of control air automatically aligns the auxiliary feedwater system to provide cooling water to the steam generator.
Decay heat removal from the reactor vessel is achieved by transferring the thermal energy to the steam generator cooling water which is converted to steam.
The generated steam is then vented to the atmosphere by opening the fail-closed air operated steam generator atmospheric relief valves (MSlO).
Control air is required to open these relief valves in order to perform decay heat removal.
Thus, the loss of control air system will not affect the coping capability in the initial phase of an SBO event.
However to, adequately perform decay heat removal, and achieve and maintain hot shutdown for the coping duration of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, operation of the above equipment will be essential.
Conclusion On the basis of the above evaluation it is evident that control air is essential in order for Salem Generating Station - Units 1 and 2 to cope with an SBO event for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
Several alternatives were evaluated to supply control air during the SBO event.
Based on this evaluation, a plant modification to add an additional source of compressed air is required.
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7.2.4 EFFECTS OF LOSS OF VENTILATION The average steady state temperature in dominant areas of concern containing equipment necessary to achieve and maintain safe shutdown during a station blackout has been calculated using the assumptions provided in NUMARC 87-00, Section 2.7.1 and the methodology provided in NUMARC 87-00, Section 7.2.4, and Appendix E.
The dominant areas of concern include the following:
- 1.
Main Control Room
- 2.
Auxiliary Feedwater Pump Room
- 3.
Main Steam Outer Penetration Area (El. 100 1 )
- 4.
Main Steam Inner Penetration Area (El. 100 1 )
- 5.
Control Equipment Room
- 6.
480V Switchgear Room (El. 84')
- 7.
4KV Switchgear Room (El. 64 1 )
- 8.
Electrical Penetration Area
- 9.
Relay/Inverter Room
- 10.
Battery Room Credit has been taken for opening area doors where feasible during the SBO event to allow for removal of heat through natural circulation.
The effect of opening the doors has been calculated as per the methods provided in NUMARC 87-00, Section 7.2.4, and/or Appendix E.
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7.2.4.1 7.2.4.2 The calculated maximum study states temperatures in the dominant areas of concern during station blackout are as follows:
ROOMS
- 1. Control Room
- 2. AFW Pump Area
- Turbine Driven Cubicle
- Electric Driven Area
- 3. Main Steam Outer Penetration Area
- 4. Main Steam Inner Penetration Area
- 5. Control Equip. Room
- 6. 480V SWGR Room 7
- 8. Elec. Penetration Area
- 9. Relay/Inverter Room
- 10. Battery Room CLOSED DOORS 256.1°F 137.3°F 211.5°F 209.3°F 114.8°F 113.9°F lll.8°F 112.3°F 121. 5 °F 116.5°F DOORS OPEN 2
104.8°F* 96.0°F*
177.9°F
- This takes into account the effect of solar radiation on the roof, which is exposed.
Operability of the equipment required for coping with a station blackout event at the steady-state temperatures reached during SBO as shown above has been evaluated as per methodologies given in NUMARC 87-00, Appendix F.
In this evaluation, SBO equipment has been assumed to be required for the entire four hour duration of the SBO event to be conservative.
This evaluation provides reasonable assurance that all equipment needed to cope with a station blackout will operate at the steady-state temperatures reached due to loss of ventilation for the entire duration of the SBO event.
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An evaluation has also been made for the effect of the steady-state temperatures reached due to loss of ventilation on the plant fire protection equipment.
This evaluation shows that there will be no inadvertent actuation of any fire suppression system during an SBO.
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7.2.5 7.2.5.1 7.2.5.2 CONTAINMENT ISOLATION An assessment was performed in order to ensure that appropriate containment integrity is provided during a station blackout event.
Appropriate containment integrity is defined such that the capability for valve position indication and closure of certain containment isolation valves is provided independent of the preferred ac or, Class lE ac power supplies.
The assessment was performed using the guidelines of NUMARC 87-00, Section 7.2.5.
Analysis Containment isolation valves reviewed are identified in Table 3.6-1 of the Salem Technical Specifications.
Per NUMARC 87-00 exclusion criteria, valves were reviewed for exclusion from further consideration.
Valves that could not be excluded using the NUMARC criteria are identified as containment isolation valves of concern.
Valve position indication was also considered.
The results of the evaluation identified four " valves of concern."
These are:
o CV68 o
CV69 o
CV116 o
CV284 3 11 Isolation Valves on Chemical and Volume Control System Charging Line 4 11 Isolation Valves on Reactor Coolant Pump Seal Water return Line These valves are dispositioned as follows:
o The local manual closure and reliance on local position indication is currently addressed for CV68 and CV69 in Unit 1(2)-EOP-LOPA-1, Step 54.
Only one is needed to be closed since they are in series.
o The local manual closure and reliance on local position indication is currently addressed for CV116 in Unit 1(2)-EOP-LOPA-1, Step 40.
CV284 is inside containment and need not be closed since it is in series with CV116.
Conclusion Based on the above analysis, no plant modification or associated procedure changes are required to ensure appropriate containment integrity during SBO.
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