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). 9. DESCRIPTION: A endix R Safe Shutdown Path 2 Anal sis for fires in the

. Control Roo'm Fire Zones- .

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10. Alternate Number. SEA-EE-061

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-19. DBD Number: DBD 019,.DBD 076

>20. PREPARED BY

Print Name Thomas'A. Gorman

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%21. REVIEWED BY

Print Name Eric R. Jebsen

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%22. APPROVED BY/ DATE

Print Name F.G. Butler

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. ENGINEERING CALCULATIONSTUDY

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REVISION NO' CALCULATIONNUMBER: EC-013-0859

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Susquehanna Steam Electric StationAppendix R Analysis for a Control Room Fire

O.Section

TABLEOF CONTENTS

Title

1.0 INTRODUCTION

. 2.0

3.0

OBJECTIVE

CONCLUSIONS AND RECOMMENDATIONS

6

4.0 ASSUMPTIONS/INPUTS

5.0 , METHODS

= 6.0 ~ REFERENCES 13

".7.0 „RESULTSI

17

~Aendicee

,C

Control Room Appe'ndix R Compliance Report

Appendix R Cable Hit Resolution Worksheets

Resolution ofMOV"Hot Short" Issue

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Susquehanna Steam Electric StationAppendix-R Analysis for a Control Room Fire

1.0

1.1

INTRODUCTIONa

Puruoae

This calculation identifiesStation (SSES) Controlcompliances (i.e. "hits").following fire zones:

those cables routed in the Susquehanna Steam ElectricRoom fire area that are potential Appendix R non-

The Control Room fire area CS-9 consists of the

0-26A0-26I0-26N

0-26E0-26J0-26P

0-26F - 0-26G -0-26H'-26K 0-26L 0-26M0-26R

In the context of this report, "Control Room" refers to Fire Area.CS-9 in itsentirety.

. For a fire in anyone of these-fire zones, credit is takeri for Safe Shutdown Path,2,Alternate Shutdown using the Remote Shutdown Panel (refer to section 1.3).

This report evaluates the Path 2 cable/component noncompliances ("hits") in FireArea CS-9 and identifies the method of achieving Appendix R compliance foreach. Appendix A provides a summary of this information. Appendix B providesthe individual hit resolution worksheets for the Path 2 cable hits in the ControlRoom. Appendix C evaluates the,NRC IN 92-18 MOVHot Short Concern for the

'SESControl Room fire.

1.2 B~ack round

In October of 1987,,Pennsylvania Power and Light Company (PPEcL) completedthe re-analysis of Appendix R Compliance Assessment for a fire in the'Control

. Room (Reference 6.2.12). This analysis identified specific- areas of non-compliance with respect to Appendix R cables required for Safe Shutdown Path 2(termed "cable'its") routed in the Control Room. Circuit isolation andconiporient cable failure modes were evaluated and recommendations for achievingcompliance were identified in the report

'

Subsequent to this, the Appendix R Closeout Project Team was formed. Thisteam's role was to implement the recommendations provided in the original issueof the analysis..In performing the actions necessary to implement therecommendations made in the analysis, modifications were performed, proceduralaetio'ns were put in place and, in some cases, additional analysis providingjustification for the acceptability of the existing condition was provided: In mostcases, the information included in this analysis required recourse to'either a DCP,

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an operating procedure or another analysis to fully understand the final dispositionfor the noncompliance.

This calculation was revised to update this Appendix R Control Room FireAnalysis by incorporating the information from each of the above-mentioned areas

'nd consolidating it into one composite location.I

Revisions 2 and 3 to this calculation were prepared to address NRC InformationNotice 92-18 related to MOV "Hot Shorts". Revision 4 was prepared to address

the revised Spurious Actuation Criteria agreed to between PAL and the'NRC.Discussions were held between PPEcL and the NRC on numerous occasionsrelative to spurious operations criteria. On January 25, 1996 a meeting was held inPP8cL's Allentown offiice to discuss the spurious actuation criteria to be applied tothe evaluation offires in fire areas outside of the Main Control Room. The results

. of this discussion was transmitted to the NRC in PLA-4442. This PLA alsotransmitted revision 3 of this calculation. which contained the evaluation of theNRC IN 92-18 MOV"Hot Short" issue.

Upon review of this submittal, NRC initiated a telephone conversation on July 25,1996 in which they informed PP&L that they wanted PAL to apply the same,spurious actuation criteria discussed for the areas. outside the Main Control Roomto the evalaution of fires in the Main Control Room. After a review of thefeasibility of honoring this request, PP8cL requested a follow up telephonecoversation on September 4, 1996 to clarify the NRC's request.

1.3

In this telecon, the NRC confirmed that the Control Room fire analysis should

apply the criteria from Generic Letter, 86-10 paragraph 5.3.10 to Control Roomcircuits isolated from the Main Control Room, should use the criteria from PL'A-4442 for all non-isolated circuits and should add consideration for spuriousinitiation of systems that could result in an inadvertent and uncontrolled RPVoverfill condition. The revised Spurious Operation Criteria was transmitted to theNRC under PLA-4505.

'F

Control Room-Fire Shutdown Scenario Path 2

For a Control Room fire, plant shutdown is accomphshed by use of the AlternativeShutdown Path controlled from the Remote Shutdown Panel (RSP). Thisshutdown path is defined as "Path 2". For a serious Control Room firenecessitating evacuation, a manual plant scram is initiated, the MDIV's

'are'anually

closed, the Reactor Feedwater'umps are tripped and the ReactorFeedwater Pump discharge valves are closed prior to evacuating the ControlRoom. Although NRC GL 86-10 Section 3.8.4 typically allows the operator toperform a plant SCRAM prior to evacuating the Main Control Room, the NRChas stated in a telecon on September 4, 1996,-that they would grant us .an

EC-013-0859 Revision 4Page g


additional operator action of closing the, MSIV's prior to evacuating the MainControl Room. Our request to have the NRC of6cially confirm this position and

grant us this additional operator action prior to Main Control Room evacuationwas documented in PLA-4505.

In addition, PLA-4505 requested that the NRC.also approve the additional pre-evacuation operator actions described above. These additional operator actionsare necessary to prevent an RPV overfill condition caused by a feedwater flowcontroller failure (high) during feedwater coastdown after closing the MSIV's,

sI

The discussion addressing the requirements of NRC GL 86-10 Section 3.8.4-regarding operator actions performed prior to leaving the Main Control Room is.contained. in section 7 of this calculation under the heading for the MSIV's andFeed water.

In the Path 2 safe shutdown scenario, Reactor Coola'nt makeup is provided by the'CIC System. The reactor depressurization function is provided by opening orie

of three specific SRVs or cycling'them from the RSP. In addition, the ability tomanually initiate ADS from-the relay rooms'has been preserved. The decay heatremoval function is provided by RHR operating in the'shutdown cooling mode.The Reactor Recirculation pumps are assured

tripped.'he

MSIVs isolate on loss of ofF-site power, manual isolation signal, or low'vacuum in the main condenser. The manual isolation signal is provided for in thePlant Procedures ON-100/200-009, and the analysis is simplified ifthe MSIVs are

'losedor can be closed for all shutdown paths. This simplifies the analysis bymaking shutdown paths the same regardless of whether or not off-site power isavailable. The NRC has stated that for SSES 'manual closure of the MSIV's by the.operator prior to evacuating the Main Control Room is an acceptable action. Inaddition to the analysis simplification features described above, this action, alongwith closing the Feedwater Pump discharge valves'and tripping the FeedwaterTurbines, mitigates the efFects of a spurious RPV injection from the FeedwaterSystem.

'he support functions either remove heat or supply power to the front line processsystem functions of reactivity control,, reactor 'oolant makeup, reactor .

depressurization and decay heat removal. Cooling for equipment's provided bythe Emergency Service Water System. RHRSW provides cooling water for theRHR System.

Power is supplied by the Emergency Diesel Generators (in the case of a LOOP)and the batteries to the various components within the AC and. DC Electrical „

Distribution System.h

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.Susquehanna Steam Electric StationAypendix R Analysis for a Control Room Fire

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'rea cooling for the RCIC Rooms, the RHR pumps, the ESWS pumps and theEmergency Diesel Generators is provided by the ECCS'Room Coolers,ESWHVAC and EDGHVAC Systems, respectively.

2.0 OBJECTIVE

This calculation revision serves to consolidate all information related.to, theanalysis performed to demonstrate compliance for the Susquehanna Steam Electric

'tation (SSES) with the requirements of 10CFR50 Appendix R for a ControlRoom Fire. This calculation was revised to:

I

'a. Incorporate changes to the safe shutdown component and cable data resultingfrom plant modifications.

b. Incorporate changes to include the final method of resolution (i.e. hitdisposition) for the Appendix R non-compliances identified in the originalanalysis.

c.'-'Incorporate as-built information from'the modifications performed, in responseto those dispositions crediting plant changes as a method of achievingcompliance in the original issue of.this analysis.

d." Consolidate .information from various studies that are inter-related andcollectively address the method ofachieving Appendix R compliance for a firein the Control

Room.'.

Document the'implementation of the Spurious Operations Criteria provided byPPEcL to the NRC in Attachment A to PLA-4505.

i

This calculation revision encompasses the criteria and assumptions for a ControlRoom fire evaluation outlined in'EC-013-0814 (Reference 6.2.10), and serves to ~

supersede that document in its entirety.

Changes made within this revision of this calculation are indicated by a revision barin the right hand column. Editorial and format changes are not noted with a

revision bar.

3.0 CONCLUSIONS AND RECOMMENDATIONS

The results compiled in Section 7 demonstrate that measures are currently in place,to address each of the potential Appendix R non-compliances (i.e. cable hits)-identified for a Control'Room fire. A rigorous review of the cable hits in Fire Area

'S-9has identified that each cable hit is adequately addressed by one or more ofthe following methods:

a. A modification was implemented to change the, circuit to provide circuitisolation.

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Sustiuehanna Steam Electric StationAppendix R Analysis for a Control Room Fire

b. An existing analysis has concluded that cable failure will not prevent safe

shutdown.c. Procedural actions are in place to manually operate equipment to satisfy the

Path 2 safe shutdown.d. Deviation requests are in place that justify the acceptability of the existing

configuration.

The review performed, as documented herein, concludes that the SusquehannaSteam Electric Station is in full compliance with the requirements of 10CFR50.48and Appendix R with respect to safe shutdown in the event of a Control Roomfire. The results of the analysis performed to address the MOV"Hot Short" Issue,NRC Information Notice 92-18, is contained in Appendix C.

4.0 ASSUMPTIONS/INPUTS

4.1 Re lato Evaluation Criteria

The criteria used to analyze for a fire in the Control Room and the ability to meet10CFR50.48 Appendix R requirements to accomplish and maintain shutdown areas follows:

4.1.1 = PP8cL is committed to 10CFR50.48, Appendix R Sections III.G, J, and O..Section III.Gcontains the requirements for fire protection capability.

4.1.2 Section III:G.3 discusses the option of providing alternate shutdown if SectionIII;G.2 separation requirements cannot be met. +

4.1.3 Section III.Ldiscusses the requirements for alternate shutdown capability. Whilenot a direct commitment, it is invoked via Section III.G.3. Therefore, SectionIII.Lrequirements apply to the analysis for a Control Room fire.

4.1.4 Generic Letter 86-10, Item 3.8.4 provides NRC guidance related to Control Roomfire considerations. The NRC has stated that for SSES an operator action to closethe MSIV's in the event of a Main Control Room Fire prior to evacuation is

. accceptable. This position has been transmitted to the NRC for formal acceptancein PLA-4505. PLA-4505 also requested approval from the NRC to trip theFeedwater Pump Turbine and close the Feedwater Pump discharge valves prior toevacuating the Contol Room.

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Susquehanna Steam Electric StationAppendix'R Analysis for a Control Room Fire

4.2 Safe Shutdown Re uirements for a Control Room Fire

."4.2.2

4.2.3

4.2.4

4.2.5

4.2.6

4.2.7

4.3

For the first'72 hours post-fire, the analysis considers shutdown with and withoutthe availability of oQsite power. After 72 hours, offsite power can be assumed

restored:I

A LOCA, seismic event, or any other.'Design Basis Accident is not considered tooccur concurrent with a fire. The fire is considered to be the single failure.

The reactor is tripped in the Control Room. The MSIV's are closed in the ControlRoom. The Feedwater Pump Turbines are tripped and the Feedwater Pumpdischarge valves are closed in the Control Room. Additional. operator actiorisprior to Control Room evacuation were not assumed.

The automatic actuation of equipment (e.g., generators, valves, pumps etc.) isassumed potentially lost if control circuits could be adversely affected by theControl Room fir'e. Spurious inadvertent actuation of equipment is considered inthe analysis. The spurious actuation criteria applied was transmitted to the NRC inPLA-4505 for formal acc'eptance. This criteria is summarized in section 4.4.4 a'nd

explained in more detailed in the Appendix R Compliance Manual, Calculation EC-013-0843. A separate analysis to document the results ofthe evaluation to addressNRC IN 92-18 related to MOV"Hot Shorts" is contained in Appendix

C.'eturn

to'the Control Room post fire is acceptable provided the specific conditionsdescribed in NRC'Generic Letter 86-10 are met. This option, however, was notused in this.analysis due to th'e difficultyofmeeting the necessa'ry conditions.

Damage to=systems in the Control Roo'm due to a Control-Room fire cannot bepredicted. Therefore, a bounding analysis was performed to demonstrate that safeshutdown to cold shutdown'could be achieved from outside the main Control-Room. The as'sumption of"limited fire" damage was not used in this analysis.

: For the equipment required for shutdown at the Remote Shutdown Panel, a reviewwas performed to determine the existence of proper isolation 'and circuitindependence from the affects of the Control Room fire. For those cases whereisolation was not adequate, measures were taken (modifications, procedural

. actions, etc.) to ensure the ability to operate the component, when required .

'

Procedural Actions and Re airs

4.3.1 Manual actions, other than those discussed in section 4;2.3, may be credited torest'ore power, assure valve lineups, isolate cable faults, etc. provided these actionscan be performed outside of the main control room and with available manpower.

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4.3.2 No "repairs" are allowed to achieve hot shutdown. Repairs to Cold Shutdown'ystems are acceptable provided specific detailed procedures, and dedicated repair

parts are available onsite and the time required to make the repairs is reconciled

with the Shutdown scenario..a

Note: The NRC designates 72 hours as the require) time to be able to reach coldshutdown.

4.4 Circuit Failure Criteria

4.4.1 The following fire damage to electrical equipment was considered:s

a) hot shortsb) open circuits

*

,c) shorts to ground

4.4.2 Ifall possible'ailure states of the equipment (valves fail open or closed) wereevaluated and found acceptable, the specific circuit failure modes were consideredto have no impact on safe shutdown.

4.4.3, =Hot short conditions were not postulated to,be cleared by the fire condition..Onlymanual actions to'solate the circuit or other appropriate manual actions wereconsidered to mitigate the spurious signal. Equipment damage due to hot shorts as

postulated in NRC IN 92-18 has been addressed by a separate analysis contained inA'ppendix C.

4.4.4 For fires in the main Control Room, SectIon III.L*requires that spurious operation'fequipment that can affect safe shutdown functions be considered. The spuriousoperation criteria for circuits isolated from the main Control Room is contained inNRC Generic Letter 86-10'paragraph 5.3.10. 'That criteria reads as follows:

~ The safe shutdown'capability should not be adversely affected by any onespurious actuation or signal resulting from a fire in any plant area; and

~ The safe shutdown capability should not be adversely affected by a fire in anyplant area which results in the loss. of all automatic function (signal, logic) fromthe circuits located in the area in conjunction with the one worst case spuriousactuation or signal resulting from the fire; and

, ~ The safe shutdown capability should not be adversely affected by a fire in anyplant area which results in spurious actuation of the redundant valves in anyone high-low pressure interface line.

For application of this criteria for all situations other than Hi/Lo pressureinterfaces, it is assumed that one spurious operation occurs prior to actuating thetransfer switch at the RSP. This spurious operation,may be as a result ofa hot

I,

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Susquehanna Steam Electric Station, Appendix R'Analysis for a Control Room Fire

short on a circuit'that is isolated from the main Control Room or on one that is

not. It is not necessary to postulate spurious operation ofequipment in each ofthese two categories: i.e isolated and non-isolated circuits.

For circuits remaining in the main Control Room that are not isolated, all potentialspurious operations must be addressed on a one-at-a-time basis. Each individualspurious operation must be identified and a mitigating action to prevent an impactto safe shutdown must be developed. In developing this mitigating action,however, it is not acceptable to ignore a potential hot short on one piece ofequipment as a mitigating action. for another piece ofequipment.

The act ofactuating the transfer switch at the RSP is the mitigating action toaddress any spurious operation for circuits isolated from the main Control Room.

— For circuits not.isolated form the main Control Room, some other means ofmitigiting the effects of the potential spurious operation must be available.

I

Examples ofways to mitigate either prior to or during the process of the fire theeffects of each spurious operation are as follows:

~ Provide a fire barrier or wrap~ Route the circuit ofconcern in a dedicated raceway that does not contain any

other normally energized circuits'that could cause a hot short'

Reroute or relocate the circuit/component~ Provide a Procedural Action, such as:

- Have the breaker-for the component ofconcern normally racked out'or

fuses removed) so that inadvertent operation is'not,possible. [Note:For Hi/Lo pressure interface components, a 3 phase hot short on the acpower cable or 2 hot shorts of the'proper polarity oil the dc power.cable must still be evaluated.]- Perform an action in response to the. fire condition to mitigate theimpact of the spurious operation. [Note: Ifthis action involvesmanually operating an MOV using the hand wheel, it must bedemonstrated that fire damage did not result in a hot short with thepotential to damage the valve (i.e. NRC IN 92-18 concern)]

- ~ Identify'other equipment, that can prevent the spuriously operated componentfrom affecting safe shutdown

For a more detailed explanation of the spurious operation criteria applied in the .

control room fire analysis see Calculation EC-013-0843 and PLA-4505.

4.4.5 For three-phase AC circuits, the probability of getting a hot short on all three'hases in the proper sequence to cause spurious operation ofa motor is considered

sufficiently.low as to not require evaluation except for any cases involvingHigh/Low pressure interfaces. For ungrounded DC circuits ifit can be shown that

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Susquehanna Stcam Electric StationAppendix R Analysis for a Control Room Fire

only two hot shorts of the proper, polarity without grounding could causespurious'peration,

no further evaluation is necessary except for any cases involvingHigh/Low pressure interfaces.

4.5 Confirmin Anal sis

. 4.5.1 The Control Rod Drive System (scram function) was evaluated in Calculation EC-013-0849 (Reference 6.2.13) and dispositioned as not a concern to, accomplish thescram function. This system was not addressed in this calculation. ~

= 5.0 METHODS

5.1 The components required for safe shutdow'n for path 2 are developed incalculation EC-013-0979 (Reference 6.2.1), Safe Shutdown Paths for FiresOutside and Inside of Control Room. The cables required,to support theperformance of. the components on this path were developed in calculation EC-013-0883 (Reference 6.2.15), Safe Shutdown Cable Selection. The completelisting ofcomponents/cables to be analyzed'for„a Control Room fire was generatedfrom the Appendix R Compliance Database Management System (ARCDMS)(Reference 6.9.1). This report is included herein as Appendix A and identifies allthe cable hits for Path 2 in the Control Room.

I

In order to ensure the accuracy and completeness of this listing, as a part of thepreparation of revision 1 to this calculation, a line by line comparison wasperformed between Appendix A of calculation EC-013-0859 Revision 0 and theAppendix A contained herein. Any differences identified were reconciled. Anychanges made to Appendix A subsequent to revision 1 were specifically checked as

a part of that revision.

5.2 Each component and associated cable identified in Section 5.1 was'reviewed to.determine whether proper isolation of the cable exists. Ifisolation with

separate'ontrol

power fusing exists, component operability is assured outside the ControlRoom. Appendix C addresses the MOVhot short concerns ofNRC IN 92-18.

'I

Jl'solationcapability was determined based on a review of schematic diagrams and""

was documented in one of the following locations:I

a. Existing Worksheets in Appendix Bb. Appendix A ofRevision 0 ofthis calculationc. Calculation EC-013-0854 (Reference 6.2.10)

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Collectively, the above-mentioned documents determine the isolation capability forall of the Path 2 cables in the Control Room.

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'.3

dix R Analysis for a Control Room Fire

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Many of the cables originally identified as not having proper isolation have beenresolved by DCPs that modified the component circuitry to provide control remote

'romthe control room'and isolation from cable, faults caused by the Control Room'ire.The specific DCP references are identified in Appendix A and Section 6.6.

The remaining cables that were not directly isolated were reviewed to analyze theeffects of electrical faults/failures'(hits) on the cables, The" failure, mqdesconsidered are as follows:

I

a) Shorts-to-Ground,, b) Hot Shorts

c)'" Open Circuits

5.4

The effect on component operation was then analyzed and the resulting effect onsystem operation was evaluated.''- If it could be shown that the failures did

not'ffect

plant safe shutdown using Path 2 capabilities, it was so documented onthe'able

hit worksheet and no further action was required.

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For those systems. that could-result in an inadvertent overfilling of the RPV, theimpacts were addressed on a system basis. The systems identified as having thispotential are: Feedwater; Condensate; CRD; Standby Liquid Control; HPCI;RCIC; RKVLPCI(ofthe non-safe shutdown division); Core Spray. Each of thesesystems was analyzed separately for its impact on safe shutdown. For any impactsa separate mitigating action was identified. The above referenced system impact

'valuations.are contained in section 7.

For cables whose failure could affect safe shutdown, the following methods wereemployed to resolve the cable "hit".

1

a) Determined if.a DCP is 'necessary to modify the circuit to provide circuitisolation.

b) Determined ifprior analysis has been performed that assures that failure willnot prevent safe shutdown. 1

. c). Determined ifprocedural actions were in, place. (e.g.,'operating procedure to'tripa power supply breaker) to satisfy Path 2 safe shutdown.

d) Reviewed and referenced deviation requests that justify the acceptability of theexisting configuration.

5.5 The results of-the analysis for the cable hits and their final disposition wer6'ocumentedon the Appendix R Analysis Cable Hit Worksheets, provided herein as

Appendix B.

5.6 A summary of the method of compliance for each cable hit was completed andprovided in Appendix A; This report documents the cable hits for a Control

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fire, the final disposition, the supporting analysis document reference, ifappropriate, and the dispositioning document reference

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5.7, A summary of the results of the analysis and evaluations is contained in Section 7.

, 6.0 —.,REFERENCES

The following references were used to conduct this study. Only those referencesidentified by a revision bar were reviewed for this latest revision of this calculation.

6.1 Re lato Documents

6:1.1 10CFR Part 50.48 and 10CFR 50, Appendix R

6;1.2 Generic Letter 86-10

06.1.3 ISSUE Inspection Procedure

64100,,'.1.4

SER, dated August 9, 1989.

6.1.5 PLA-4505, Spurious Operation Criteria for Fires at SSES

6.2 Calculations

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New No. Rev.

6.2..1 EC-013-0979 0

Old No.

SE-B-NA-016

6.2.3 EC-013-0845 0 SEA-EE-051

6.2.4 EC-013-0860 0 SEA-EE-020

. 6.2;5 EC-013-0964 06.2.6 EC-013-0624 0

SE-B-NA-038SE-AAA-059

6.2.7 EC-013-0725 0- SEA-EE-078

6.2.8 EC-013-0863 0 SEA-EE-060

6.2.9 EC-013-0814 0 SEA-EE-057

6.2.2 EC-013-0858 0 SEA-EE-019

Title

Safe Shutdown Paths for Fires Outside andInside Control Room

'ppendix R Required Cables for theMSIV'sAppendix R.ADS/SRV Spurious CableAnalysisEvaluation ofReactor Recirculation System

,=- Cables for Appendix R ComplianceMain Steam Line Drain ValvesAppendix R - Coordination Calculation forDiesel Generator Synchronization CircuitsAppendix R Evaluation ofNCRs 88-0007through 88-0012

'ppendix R--Hit Resolution for CSHVACComponents/CablesAppendix R - S/D Path 2 Analysis in CRFire Zones '(addItional components)

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6.2.12 EC-013-'0849 „,0 SEA-EE-017

. 6.2.13 EC-013-0883 06.2;14 EC-013-0873 0

SEA-EE-012SEA-EE-033

'.2.15EC-013-0788 0 SEA-EE-447

6.3 ~Drawin s

6.2.10 EC-013-0854 0 SEA-EE-018,

6.2.11 EC-013-0846 0 SEA-EE-052

Verification ofEquipment Isolation at theRSP in the event ofa CR fireEvaluatiori ofAppendix R VentilationSystem Non-CompliancesAcct ofFire on the Operation ofSDV Ventand Drain ValvesSafe Shutdown Cable Selection ~

Evaluation to Ensure Isolation ofRCS FlowDiversio'n in the Event ofa Plant FireDisposition ofEDR G10122 - Appendix RFlow Diversion Components - HPCI

6.3.1 E-296,E-297, SSES,Unit 1 & Common, G.E./Bechtel Cable No. Cross-Reference,dated 3/06/86.

'.3.2E-298,E-299, SSES Unit 1 & Common, G.E./Bechtel Cable No. Cross-Reference,dated 3/06/86.

6.3.3 'E-294, Revision 5, Open, List ofRaceway Wrapped with Fire Barrier MaterialUnit 1 and Common.

6.3.4 E-295; Revision 4, 10/09/86, List ofRaceway Wrapped with Fire Barrier MaterialUnit 2.

6.3.5 ElP0600, Interim Drawing Change Notice, IDCNNo. 2, dated 6/17/87.6.3.6 Panel Module Wiring List

M1-H12-538-2M1-H12-226Ml-H12-586Ml-H12-543,M1-H12-562M1-H12-530Ml-H12-563Ml-H12-1082Ml-H12-590Jl-867Ml-H12-589Ml-H12-529

, Ml-H12-553M1-H12-704

Rev.5

3

14

17 ~

'1215

13

3'04

'l l910

14

Date8/15/856/15/838/15/856/3/839/9/855/8/801/13/867/11/859/9/8510/81

1/31/858/2/83 =

4/10/8510/16/84

Panel Module0700070'1

'70207030704,0705

. 0706~ Control Room'ontrol RoomControl RoomControl Room

070007010702

EC-0134859 Revision 4Page /Q


6.3.7 Raceway Schedule

D~iN .

E-72E-73E-74E-76E-77E-78

6.3.8 Circuit Schedule

Rev.656462

. 504953

Date.1/2/86

11/6/858/2/84

8/31/841/3/85

5/29/84

D~iN:E-82E-83E-84

- E-86E-87E-88

Rev,. 60

59

56'6

4349

Date1/2/86

1.1/6/85

8/2/84 .

8/3 1'/84

1/3/855/29/84

6.3.9 Schematic Diagrams - Sheets'and revisions as noted in the Appendix B'orksheets.

6.3.10 DCN 88-0933 - ESW Flow IndicationP

6.3;11 M-1002, Revision 3, Appendix R - Safe Shutdown Component ListN

6.4 Procedures

Procedure. Rev. Title'

6.4.1 EO-100-1026.'4.2 EO-200-1026.4.3 EO-100-1126.4.4 EO-200-1126.4.5 GO-100-0026.4.6 GO-200-0026.4.7 ON-013-0016.4.8 ON-030-0016.4.9 ON-054-0016.4.10 ON-100-009,6.4.11 ON-104-0016.4.12- ON-200-0096.4.13 OP-024-001

777722244

p 3

. 3

3

3

3

10

RPV Control'RPV ControlRapid DepressurizationRapid Depressurization

~ Plant Startup, Heatup and Power OperationPlant Startup, Heatup and Power Operation,Response to FireLocal, Operation ofControl Structure HVACLoss ofEmergency, Service Water (ESW)Control Room EvacuationUnit 1 Response to Loss ofQuite Power

, Control Room EvacuationDiesel Generators

EC-0134859 Revision 4Page /W


6.4.14 OP-054-001 8

6.4.15 OP-149-002 226.4.16 OP-249-002 256.4.17 OP-100-00.1 ' .

6.4.18 OP-200-001 "'

. 6.5 .Deviation Re uests

I ~

Emergency Service Water System (ESW)RHR Operation in Shutdown Cooling ModeRHR Operation in Shutdown Cooling ModeRemote Shutdown - Normal Plant Operating LineupRemote Shutdown - Normal Plant Operating Lineup

'I

6.5.1'eviation Request No. 2, Revision 4, "Suppression Pool Temperature Indication".6.5.2 Deviation Request No. 37, Revision 4, "Control:Room Raised Floor and Control.

Structure Cable Chase Fire Protection"./

6.6 Modifications.

DCP6.6.1 86-3008C6.6.2 86-'3008D

6.6.3 86-3008E „

6.6.4, 86-3008F6.6.5 86-3009C6.6.6, 86-3009D

6.6.7 86-3009E6.6.8 86-3009F

. 6.6,9 86-3010C6.6.10 86-3010D6.6.11 88-3016H6.6.12 88-3016I

I

6.6.13 88-3016J *

6,6.14 88-3016K

6.6.15 88-3016L

6.6.16 88-30'16M

6.6.17 88-3016N6.6.18 88-3017A6.6.19 88-3017E6.6.20 88-3017F6.6.21 88-3018E

. 6.6.22 88-3018F-

I

TitleHVACFan Operation Transferred from Control RoomRHR Pump Room Cooling Fan Operation Transferred fromControl RoomHVACFan Operation Transferred from Contrdl RoomUnit 1 RHR SW Pump Room Fan ControlHVAC Fan Operation Transferred from Control RoomRHR Pump Room Cooling Fan Operation Transferred fromControl RoomHVACFan Operation Transferred from Control RoomUnit 2 RHR SW Pump Room Fan ControlHVACFan Operation Transferred from Control Room-Common Unit ESW Pump Room Fan ControlAdd 2nd Location for CS HVAC OperationESW Loop A and Loop B Diesel Generator Coolers Supplyand Return Isolation ValvesDiesel "A"Operation - ModifyWiring on Local'ontrolSwitchDiesel "B" Operation - ModifyWiring on Local

Control'witch

Diesel "C" Operation - ModifyWiring on'Local ControlSwitchDiesel "D" Operation - ModifyWiring on Local ControlSwitchDG E ModifyWiring on Local Control SwitchEmergency Switchgear Room Cooling Fan

. RHR HX SW Valves HV-11210B and HV-11215B - Unit'1RWCU Isolatio'n Valves - Fire in the Control RoomAppendix R Cable isolation for RHR SW ValvesRWCU Valve Isolation for Control Room Fire (U2)

EC-0134859 Revision 4Page /C

s


6.7 'n ineerin Work Re uests

EWR6.7.1 M80821

. 6.7.2 M808056.7.3 M80546

Title I

Ap'pendix R - Cables/Components for Emergency Diesel'eneratorOperation

Unit 1 - RWCU Valve'IsolationAppendix R - ESW Issues Analysis

6.9 DatabasesV

6.9.1 Appendix R Compliance Database Management System (ARCDMS), datedNovember 1, 1994 (including outstanding change'mechanisms through August 23,1995)

6.9.2 SEIS Equipment Index, dated 7/22/87.

6.10 Miscellaneous

V'.10.1PAL Memorandum No. EE1233, dated 9/24/87,'ppendix R'Activity 10-Raceways Recommended to be Protected.

6.11 Non-Conformance Re orts

6.11.1 NCR 87-0,7256.11.2 NCR 87-07266.11.'3 NCR 87-07446.11.4 NCR 87-0745,

7.0: RESULTS

7.1 Cable Hit Resolution Re oit Develo mentv

vI

As a part of revision i to this calculation, the Cable Hit Resolution Report~

(Appendix A) generated from the Appendix R Compliance Database ManagementSystem (ARCDMS) was verified "line by line" to ensure consistency withAppendix A of the previous'revision (Reference 6.2.12). DifFerences between thetwo reports were reviewed and justified. Any'hanges to this information as a

result ofsubsequent revisions were checked as a part of that revision.l

J'

EC-013-0859 Revision 4Page /7

I

0K

I

Susquehanna Steam Electric StationAppendix R Analysis for a Control Room Fire-

7.2 Cable Hit Worksheet Develo mentJ

Revision 1 of this calculation reviewed and updated all cable hit worksheetsaffected by the implementing actions taken as a part of the Appendix R CloseoutProject.

Cable hit worksheets for the CSHVAC cable hits were extracted from. calculationEC-013-0863 (Reference 6.2.8). Some cable hit worksheets for cables for certainRCIC components were extracted from calculation EC-013-0814 (Reference6.2.9). These worksheets were included in Appendix B so that all worksheets forthe Control Room Analysis would be contained in one location.

t

In some cases, a separate study addresses the specific cable hits (e.gts certain cablehits for RBHVAC, Flow Diversion, SPM and RCIC). In such" cases, a worksheetwas not developed for the specific cable hit,and instead, the respective applicablecalculation was referenced iiiAppendix A. =

In some cases, a cable hit is associated with a number of different components. Inmany such cases, only one cable hit worksheet was generated and each of thecomponents was identified on the worksheet.

7.3 Cable Hit Evaluation Summa b .S stem-

The following is a discussion on a system basis of the implemented solutions for'esolvirigPath 2 cable hits or potential system impacts identified or postulated for

'

Control Room fire:

7.3.1 ADS

Calculation EC-'013-0845 (Reference 6.2.3) concluded that for a fire in the ControlRoom to spuriously actuate ADS at least two (2) hot shorts in conjunction withthe spurious operation of a CS or RHR pump must occur simultaneously.. TheADS circuit for one division.requires that pressure permissive contacts (K9A andK10A) be closed when the low pressure system is available. Therefore, spuriousoperation ofADS due to a fire in the Control Room is not considered credible.

As a more plausible but still not credible event, it can be postulated that a ControlRoom fire could result in two selective hot shorts on'the ADS actuation circuitrysuch that, upon initiation of the RHR pump by the operator from the'emote'Shutdown Panel, a spurious ADS actuation could occur. In the unlikely event thatthis were to occu'r, the effect of this event„loss,of motive steam to drive RCIC,'ould be mitigated by use of the RHR System in the LPCI 'mode from the RemoteShutdown Panel to achieve a Path 2 safe shutdown. Eventually, RHR could be

~

+s

EC-013-0859 Revision 4,Page /g

L

Susquehanna Steam Electric StationAppendiz R Analysis for a Control Room Pire

placed into the Alternate Shutdown Cooling mode for accomplishing the decayheat removal function.

,Therefore, the loss of RCIC at the Remote Shutdown Panel due to a spuriousADS, even though considered to be a non-credible event, would not affect the

'bilityto achieve and maintain safe shutdown.

.732 Conderisate'\Inadvertent injection by the condensate system could be postulated as a result of a

Control Room fire. This inadvertent injection, however, would'ot be possibleuntil the reactor pressure was reduced to below 600 psig. The normal operating.pressure'or the SSES reactor is 1050 psia which corresponds to a temperature'f550 F. 'The condensate„system shutoff head of 615 psia corresponds to a

temperature of 489'. This represents a temperature difference of 61 F. At a

vessel cooldown rate of 90'i hour, it would take approximately 40 minutesbefore vessel pressure would reach the level at which condensate could inject.

Since this condition willnot occur until the vessel is at a lower pressure and a verylow power level, an analysis'will be performed to determine ifthe SRV discharge

piping can sustain the loads from this condition. Since adequate time exists toperform an operator action to prevent or mitigate the effects of this condition, this,remains as an option should the'results of the analysis described above not befavorable.

'ince

a LOOP will cause a loss of power to the 13.8 kv switchgear, this operatoraction will only be required ifa LOOP does not occur with the fire. Therefore,should this action be required to be performed, normal lighting should be available.As a result, emergency lighting to meet the requirements of Appendix R SectionIII.J need not be installed's long as it can be shown that the fire will not damagenormal lighting.

7.3.3 CRD

The postulated concern for the CRD system circuits that-are not isolated from the-main Control Room is the inadvertent and uncont'rolled" injection into the RPVresulting in a vessel overfill condition at high pressure. This condition for CRDwould re'suit in an injection rate of less than 100 gpm. An injection rate of thismagnitude would allow greater than 30 minutes for the operator to respond. Theoperator would respond by taking control of the unit at the RSP. The impact ofinadvertent, CRD injection would be mitigated by throttling.back on the RCICinjection rate at high pressures and the RHR SDC injection rate at low pressures.

'herefore,ina'dvertent injection by the CRD system will have "no impact on safeshutdown.

'C<13-0859Revision 4Page


7.3.4 CSHVAC.

A fire in, the Control Room could damage cables for Control. Structure HVACequipment, by causing grounds, open circuits, or hot shorts. 'The cable failureswere analyzed in Calculation EC-013-0863 (Reference 6.2.8) and those that couldprevent the proper functioning of equipment, and potentially result in the, loss of,CSHVAC, were identified.

A modification was performed (DCP 88-3016H) to provide a backup control panelto ensure that in case of a Control Room fire, the CSHVAC system componentsrequired for Pa'th 2 safe shutdown would remain functional. The "new" ControlStructure HVAC Alternate Control Panel OC879 was installed in Area 21,Elevation 783'-0" and provides for local operation arid for isolation from ControlRoom damaged circuits. During normal plant operation, the transfer switches arein the normal position and the control switches are in the auto position.

In addition to the alternate HVAC panel, Plant Procedure ON-100/200-009requires an operator to secure any, battery equalizing charges in progress and toimplement Procedure, ON-030-001 to restore Battery Ro'om Ventilation, iflost dueto a fire in the Control Room.

For the case of a fire in the Control Room, procedural actions contained inProcedure ON-030-001 assure that the smoke from the Control Room fire willnotacct those areas of the Control Structure that must be habitable for remoteoperation of the CSHVAC System.

By performing the above-mentioned procedural actions and controlling CSHVACat Panel OC879, the availability ofCSHVAC to support Safe Shutdown Path 2 fora Control Room fire is preserved.

7.3.5 CSS

In the event of a fire in the Control Room, certain cables for the Core SpraySystem automatic initiation logic could fault, potentially resulting in the spuriousactuation ofa Core Spray Pump.ll

Core Spray System circuits'are not isolated from the Main Control Room. By'ssuminga number of independent spurious operations on the Core Spray System

components, a vessel'overfill condition caused by inadvertent injection could be'

postulated. Should this condition occur, it would not occur until the RPV was atlow pressure and safe shutdown could still be accomplished by furtherdepressurizing the RPV with the SRV's available at the RSP, using RHR in theLPCI mode and, ultimately, using RHR in the Alternate Shutdown Cooling mode:Any excess water flow from the Core Spray System resulting from this condition

\

EC-0134859 Revision 4Page ZO

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0

Susquehanna Stcam Electric StationAppendix R.Analysis for a Control Room Fire

t

E

could be integrated with the shutdown approach described above with no impactto safe shutdown.

7.3.6 EDG HVAC

Ventilation Fans OV512A, B, C, D are required for cooling of the Diesel GeneratorRooms and c'ould be lost due to a fire in the Control Room. Without the fanrunning the room temperature could exceed the recommended operating designtemperature of the equipment, and could prev'ent.the system from performing itsintended safe shutdown function. l

.In the original design, a Control Room fire-induced fault could-either blow thecontrol circuit fuse or create an open circuit, thereby disabling fan control from the

'ontrolRoom.. However, new temperature switches (TSHL-08271A, B, C and

D), one in each Diesel Generator Room, have been installed (per DCP 86-3010C)to automatically start the respective room fan when room temperature exceeds theswitch-setp oint:

This modification isolates the Control Room portion of the circuitry and thusassures that the Diesel Generator Room fans willoperate to support safe shutdownPath 2 in the event of a Control Room fire. No operator response is required as

the fan automatically starts on high temperature.C I

.7.3.7 ElectricalI /

A. Diesel GeneratorsI

Diesel Generators A, B, C and D are standby power supplies which provideClass lE power to the Appendix R Safe Shutdown equipment in the event oftotal loss of'ooffsite power. A fiAh diesel, diesel generator is available as asubstitute if.any one of the four diesel units is temporarily 'out of service.However, no credit is taken for Diesel Generator E to achieve Appendix R .

compliance.

Each of the diesel generators'an be 'operated at their respective localgenerator and engine control panels (OC519A'thro'ugh E and OC521A throughE).or at the plant operating benchboard (OC653) in the main Control Room. Alocal-remote selector switch enables the operator to transfer control from themain Control Room to the local panels by isolating the control circuits

from'C653.

1 /In the original design, the selector switch in the Control Room panel isolatedonly one side of the remote control circuits. Thus, a Control Room fire whichresults in conductor shorts or shorts to ground at OC653 could have disabled

EC-013-0859 Revision 4Page 7 /


I

the engine or generator control circuits and prevented operation from the localcontrol panels for a Path 2 safe shutdown. Since a loss of oAsite power wasassumed for this fire, the unavailability of the diesel generator during a ControlRoom fire would adversely aFect safe shutdown capability."

Modifications (DCP 88-3016J, K, L, M and N) were performed to completelyisolate both sides of the Control Room circuits. This design ensures that localcontrol of the diesel generators remains available in the event of a ControlRoom fire. Procedure ON-100/200-009 contains the operator action to locallystart the Diesel Generators, ifrequired, in response to a loss ofoffsite power..

B. 4.16KV Safeguards Switchgears

In the event ofa Control Room fire, certain cables for control and indication ofthe breakers from the Emergency Diesel Generators to the 4.16 kV ESSSwitchgears could fail resulting in the loss of power to the buses. However,this cable fault can be isolated by operation of a local control switch.Procedures ON-100/200-009 require an operator to'manually close the breakerat the switchgear in order to re-energize the bus, should the breaker fail toclose automatically.

'I

I

To prevent failures in the following associated circuits (of a common powersource) cables from causing loss of 4.16KV Safeguards Switchgear 1A201,1A202, 1A203, 1A204, 2A201, 2A202, 2A203, and 2A204, circuitcoordination between the primary and secondary side fuses of the potentialtransformer was performed in Calculation EC-013-0624 (Reference 6.2.6) forthe following cables:

Cable

1) NK1A0401G2) NKIA0402G3) NKIA0403G4) NK1A0404G5) NK2A0401G6) NK2A0402G7) NK2A0403G8) NK2A0404G

~Com onent4.16KV Safeguards Switchgear 1A201'4.16KV Safeguards Switchgear 1A2024.16KV Safeguards Switchgear 1A2034.16KV Safeguards Switchgear 1A2044.16KV Safeguards Switchgear 2A2014.16KV Safeguards Switchgear 2A2024.16KV Safeguards Switchgear 2A2034.16KV Safeguards Switchgear 2A204

The calculation concluded that adequate circuit coordination currently exists.'

Thus, a fire in the Control Room will not impact the availability of the 4.16KVSwitchgears to support safe shutdown due to associated circuits concerns.

EC-013-0859 Revision 4Page Z.2


'.3.8

ESW,HVAC

Ventilation Fans 1V506A, B and 2V506A, B are required for cooling of the RHRService Water Pump Rooms. Fans OV521A, B, C and D are required for coolingof the ESWS Pump Rooms. Each of these fans could be lost due to a fire in theControl Room. Without the fans running, the respective room temperature couldexceed the recommended operating design temperature of the equipment, andcould prevent the system fr'om performing its intended safe shutdown function.

In the original design, a Control Room fire-induced fault could either blow thecontrol circuit fuse or create an open circuit, thereby disabling fan control from theControl Room. However, new temperature switches in the respective pumprooms have been installed, as noted below, to automatically start the respectiveroom fan when room temperature exceeds the switch

setpoint.'Com

1V506A1V506B2V506A2V506BOV521AOV521BOV521COV521D

D~escri tiooRHRSW Pump Room Fan

~ RHRSW Pump Room FanRHRSW Pump Room FanRHRSW Pump Room FanESSW Pump Room FanESSWiPump Room FanESSW Pump Room Fan,

'SSWPump Room Fan,,

TempSwitchesTSHL-18201ATSHL-,1 8201BTSHL-28201ATSHL-28201BTSHL-08206ATSHL-08206BTSHL-08206CTSHL-08206D

DCPReference86-3008F86-3008F86-3009F86-3009F86-3010D86-3010D86-3010D86-3010D

1

These modifications isolate the Control Room portion of the circuitry, 'therebyassuring the operability of the pump room fans to support Safe Shutdown Path 2 inthe event of a Control Room fire. No operator response is required as the fansautomatically start on high temperature.

7.3.9 ESWS

The Emergency Service, Water (ESW) System provides cooling water to theEmergency Diesel Generators which are required for Appendix R Safe Shutdown.Each loop supplies cooling w'ater to the diesel coolers through separate inlet andoutlet motor operated valves. Control of the valves is from the Main ControlRoom Panel OC653

In 1988, an evaluation was performed which indicated that a fire in the MainControl Room could have caused control cables associated with either the ESWvalve controls on OC653 or the auto-loop transfer logic to be damaged, thereby,impacting the operability of ESW. The valves on both loops could have also

'puriously closed due to a short in the control. cables. Such spurious closure of the

EC-013-0859 Revision 4Page gg

E5

,(

. ~

Susquehanna Stcam. Electric StationAppendix R Analysis for a Control Room Fire

valves would had to have been immediately corrected whenever the diesel engine is .

running to support Appendix R safe shutdown.h

To prevent loss of Emergency Service Water to the Diesel Generator-coolers,isolation, of the following cables and local control for the following valves'was

"necessary. '

Cable ~ * ValveAKOS0404C, G HV-01112AAKOS0405C, G - HV-01122ABKOS0406C, G HV-01112B,BKOS0407C, G . HV-01122BCKOS0408C, G —. HV-01'112CCKOS0409C, G . HV-01122CDKOS0410C, G HV-01112DDKOS0411C, G . HV-01122D

e

A modification was implemented (DCP 88-30161) which removed control of theESW valves from the main Control Room panel OC653, and located it to newcontrol pariels OC521A, B, C and D. Therefore, a fire in the Control Room willnot impact the operability of the ESW System to support Safe Shutdown Path 2.

7.3.10 Feedwater

'he

concern for the spurious operation of the feedwater circuits that are notisolated from the main Control Room is the inadvertent and uncontrolled injectionby the feedwater system resulting in a vessel overfill condition at high pressure. 'As

' mitigating action, the NRC has stated that the use of an immediate operator '

action to close the MSIV's prior to evacuating the'main Control. Room is an

acceptable mitigating action. Closing the MSIV's will remove the motive steam tothe feedwater turbine and steam driven pump.'his alone, however, will not stopfeedwater injection and prevent any impact to safe shutdown.

. Ifafter performing this action, the feedwater flow controller were to fail high inconjunction with a loss of the 54" feedwater trip there is a sufficient amount ofsteam available in the'main steam system to continue to drive the feedwater turbinedriven pump such that a vessel overfill condition would result in less than 1,minute.To prevent 'this condition an additional operator action to close the feedwaterpump discharge valve prior to evacuating the Control Room is necessary. 'This is'

currently an immediate operator action in the Control Room EvacuationProcedure, ON-100/200-009.

This 'additional action, however, will not prevent the undesired condition fromoccurring since the circuits for feedwater pump discharge valves are not isolated

'C-013-0859Revision 4Page

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Susquehanna Steam Electric StationAppendiz R Analysis for a Control Room Fire

from the Control Room and; as such, are susceptible to post evacuation hot shorts.As" a positive action to assure that this condition does not occur, the,feedwaterturbines must also be tripped by the operator prior to evacuating the Control

, Room.

It has been verified that a hot short cannot restart the feedwater turbine once it has

been tripped. This is true since re-starting the turbine requires that the operatordrive the motor speed changer to zero, press the tuibine reset button and, then,increase turbine speed with the motor'speed.changer. In addition, the feedwaterpump discharge'valve for the particular turbine must also spuriously open. Thiscombination ofcable faults is considered to be too remote to be credible.

"

. Each of these actions at the "operating benchboard, 1/2C651, in the same vicinitywhere the unit. is scrammed. Therefore, both of these actions could be performedin. rapid sequence'following the action of manually scramming the unit.'hecombined time.to perform 'these actions in conjunction with the reactor scram, and

closing the MSIV's is estimated to be on the order of 1 minute.y

7.3.11 Flow Diversion

A. Reactor Head Vent Valves

In the event of a'ontrol Room fire, inadvertent RCS blowdown via thespurious opening of the Reactor Head Vent Valves HV-B21-1F001, 1F002(Unit 1), 2F001 and 2F002 (Unit 2) is p'revented by normally depowering,the1F001 and 2F001 valves. Startup procedures GO-100-002 and GO-200-002require an operator to lift lead 1R at the MCCs specified

below.'alve

~SHV-B21-1F001 MCC,1B236 Cubicle 102HV-B21-2F001 . MCC 2B236 Cubicle 102

H

Since these valves "are de-powered closed during normal plant operation,'aControl Room fire cannot result in spurious actuation of both'series valves.This precludes the possibility offlow diversion via the Reactor Head Vent line.

B. Main Steam Line Drain Isolation Valves

Spurious opening or failure to close the Main Steam Line Drain Isolation'alvesHV-B21-1F016, 1F019, 2F016 and 2F019 is possible as a result of a

Co'ntrol Room fire. However, Calculation EC-013-0964 (Reference 6.2.5) has

determined that the flow diversion that would result in the event both isolationvalves were to open would be insufficient to impact Path 2 safe shutdowncapability. 'dequate steam generated by decay heat would beavailable,to

EC-013-0859 Revision 4

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/

support RCIC operation despite the flow diversion to the', HP Condenser.Therefore, the spurious opening ofboth valves in series would not impact SafeShutdown Path 2.

For the condition described in Appendix C, Resolution of the MOV,"HotShort" Issue, prior to entering RHR in the Alternate Shutdown Cooling mode, .

it'must be assured that the main steam line drain is isolated from the HPCondenser.. Calculation EC-,083-0530, Effect of Flow Diversion through theOpen Main Steam Line Drain Valves, has determined'that, when using

'Alternate Shutdown Cooling, this line must be isolated in approximately 10

hours in order to prevent an impact to the ECCS systems taking suction fromthe Suppression Pool. In order to isolate this system, either the F019 or theF021 and F033,valves must be closed.'his operator action applies to both,units. An operator action has been added to drawing E-690 to capture thisrequired operator action.

Since this action is not required for a minimum of 10 hours after the event, 8

hour battery powered emergency lights would not be effective in aiding theoperator. -Due to the simplicity of this action, hand-held lighting routinelycarried by the operators is considered to be adequate for this action.

Reactor Water Clean-up Isolation Valves-

To isolate the RWCU System for a fire in the Control Room, either isolationvalve HV-G33-1F001 (2F001) or HV-G33-1F004 (2F004),is required to closeand not spuriously open to preclude RCS flow diversion. In the originaldesign, neither valve was isolated for a Control Room fire. A Control Roomfire could have resulted in cable faults leading to the inability to close or thepotential spurious opening of the two Reactor Water Cleanup Isolation Valves

-HV-G33-'1F001, 1F004, 2F001 and 2F004. This condition in conjunctio'n withthe spurious opening of the HV-G33-1F033/2F033 valve would create a flowdiversion.

I

, Although the RWCU letdown line has pressure switches on „either side of theF033 valve that willactivate to de-energize and close this valve protecting thepiping system in the event of an inadvertent opening of the F033 valve, amodification (DCP 88-3017F and 18F) was implemented to provide valvesHV-G33-1F004 and 'HV-G33-2F001 with circuit, isolation through a newisolation control transfer switch at the Remote Shutdown Panel. The

transfer'witch

is dedicated to valves HV-G33-1F004 and HV-G33-2F001. Thededicated transfer switch provides the operator at the Remote Shutdown Panelwith the flexibilityto determine when letdown through the RWCU System is to

"

be terminated or restored.

EC-013-0859 Revision 4Page 2 +


The circuit isolation ensures that the valve is protected from spurious operationin the event of a Control Room fire. The valve opening circuit, closing circuitposition indication and thermal overload bypass circuits were modified withremote shutdown isolation contacts such that all Control Room components

,

and devices are isolated upon transfer to the Remote Shutdown Panel 1C201

(2C201).

D. Suppression Pool Filter Pump Suction Valves

The potential for spurious actuation of both valves HV-15766 and HV-15768(Unit 1) or HV-25766 and HV-25768 (Unit 2) was evaluated in CalculationEC-013-0725 (Reference 6.2.7). Due to a lack of circuit isolation, a ControlRoom fire can result in inadvertent flow diversion via the Suppression Pool.Filter Pump Suction Valves. Therefore, an operator action to close thesevalves should a decrease in suppression pool level occur has been included inthe plant procedures. See Calculation EC-013-0725 for the details.

7.3.12 HP,CI!

Calculation EC-013-0788 evaluated the impact on plant 'safe shutdown of a

spurious initiation of HPCI during a Control Room fire.'purious initiation ofHPCI would only be a concern ifthe reactor high level trip was defeated by thesame fire'.

This condition can be postulated to occur from a combination of a hot shortsand/or two shorts to ground on the start and/or control circuitry for selectedcomponents. Should this condition occur, action must be, taken to mitigate theefFects of the event within approximately 3 minutes. 'o address this, a plantmodification will be implemented to prevent the condition from occurring. SeeCalculation EC-013-0788 for the. details.

The condition of three independent hot-shorts causing spurious operation of thesystem and the condition of sequential selected cable faults on the HPCI controlcircuitry that initiates the system for 25.to 30 seconds and then is overcome by afault to ground which disables,.the 54" trip within.the next 30 to 40 seconds havebeen reviewed'with the NRC and are considered to be a non-credible event that arenot required to be included in the Appendix R design basis. '

7.3.13. MSIVs

In the event of a Control Room fire, various cables for the Inboard Main SteamIsolation Valves (HV-B21-1F022A, B, C and D and HV-B21-2F022A,', C and

D) and Outboard Main Steam Isolatio'n Valves (HV-B21-1F028A, B, C and D andHV-2F028A, B, C and D) could experience a fire-induced fault to cause the

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MSIV's to remain open. An inadvertent opening of two,MSIV's in any, singlemain steam line could result in an undesired RCS blowdown. These cable faults,however, would not prevent closure of the MSIV's should a trip signal from

a'rocessvariable, such as low condenser vacuum or low, low, low'eactor vessel

level, be received.l I

To address the condition of an inadvertent and uncontrolled injection'f thefeedwater system, the NRC has stated that man'ual closure of the MSIV's will beallowed for SSES as an immediate operator action. This action will remove themotive steam from the feedwater turbine driven,pump and prevent injection by

'eedwater. To use an immediate operator action, other than a reactor scram, for,

the Control Room fire scenario Generic Letter 86-10 requires a demonstration ofthe capability to'perform the action and an assurance that a subsequ'ent.spuriousoperation cannot negate the e6ects ofthe manual action.

For the action of manually closing the MSIV's prior to evacuating the mainControl Room, it has been'verfied that a subsequent spurious operation cannotnegate the effect (i.e a subsequent hot short or series of hot shorts cannot reopenthese valves)., This action is currently included in Procedure ON-100/200-009,Evacuation of the Control Room, as an immediate operator action. Since thelocation from which the reactor is scrammed is within a few feet of the locationfrom which the MSIV's will be closed, it is reasonable to assume that this actioncan'be accomplished in a short period of time by a single operator. As such, thisadditional immediate operator can be performed in the event of a Control Roomfi're. The combined time for performing this action in conjunction with the reactorscram and the actions itemized above for the feedwater system is estimated to beon the order of 1 minute.

As a'n added precaution to assure these valves are closed, Procedures ON-100-009and.ON-200-009 require an operator to trip the following breakers in the event ofa Control Room fire.

Breaker1Y201A-CB2A and 1Y201B-CB8B

2Y201A-'CB2A and 2Y201B-CB8B

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ValvesHV-B21-1F022A, B, C and DHV-B21-1F028A, B, C and DHV.-B21-2F022A, B, C and DHV-B21-2F028A, B, C and D

Removing power to the MSIVs ensures that, the outboard and inboard MSIVs areclosed in the event ofa Control Room fire.

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7.3'.14 RBHVACI

4'he

Reactor Building Ventilation System fans are required operable to provide =

cooling to various rooms to support Safe Shutdown Path 2. Without the fanrunning, the room temperature could exceed the recommended operating designtemperature of the equipment, and could prevent equipment within.the respectiveroom from performing its intended safe shutdoWn function.

Temp DCP~Com . D~escri tion 'witches Reference.1V210B RHR Pump Room Unit Cooler Fan TSHL-17660B 86-3008D2V210A RHR Pump Room Unit Cooler Fan * TSHL-27660A,86-3009D1V208A RCIC Pump Room Unit Cooler Fan TSHL-17661A 86-3008E2V208A RCIC Pump Room Unit Cooler Fan TSHL-27661A 86-3009E1V222A Emg. Swgr. Room Unit Cooler Fan TSHL-17631A 86-3008C2V222A 'mg. Swgr. Room Unit Cooler Fan TSHL-27631A 86-3009C

s /

Cable- Hit Worksheets for the above-mentioned components are provided inAppendix B with the exception 'of the following cables: FKOV1451M,FKlB2541C, D, E, F (for 1V222B) and FK2V2541F (for 2V222B). These cablehits are dispositioned in Calculation EC-013-0846 (Reference 6.2.12).

In the original design, a Control Room fire-induced fault'to certain cables for these.fans could either'low the control circuit fitse or create an open circuit, therebydisabling fan control from the Control Room. However, new temperatureswitches in the individual rooms have been installed; as noted below,

to'utomaticallystart the fan when the room temperature exceeds the switch setpoint.e

The temperature switch co'ntrol scheme does not require any operator response asthe fan automatically starts on 'high temperature to maintain room temperaturewithin design limits.

Therefore, a fire in the Control Room. will not impact the availability of theRBHVAC System to support Path'2 Safe Shutdown.

/7.3.15 RCIC

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The RCIC components required for Path 2 safe shutdown are properly is'olatedfrom'a Control P.oom fire. The potential impact of spurious operation of RCICcomponents resulting from the fire-induced damage to cables for the RCICautomatic actuation logic was evaluated and determined not to impact. safeshutdown. Sufficient time exists to take control of the RCIC system at the RSPand to mitigate the effects of any spurious operations affecting the RCIC system.See Calculation EC-0i3-0788 for details:

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'Susquehanna Steam Electric StationAppendix R Analysis for a Control Room Fire

,7.3.16 RHR

The circuitry'for the majority of the RHR components required for Path 2 SafeShutdown are properly isolated from a Control Room fire. However', several"cables for the RHR automatic actuation lo'gic and one cable for valve HV-E11-2F008 are not isolated. Fire-induced faults to select RHR automatic actuationlogic cables could result in inadvertent spurious actuation of RHR safe, shutdowncomponents., In addition, fire damage to the 2F008 cable could precludeoperability of the valve from the RSP. These cables are. routed in the space belowthe Control Room. raised floor (in Fire Zones 0-26G and 0-26J) and in the "cable

shaft under the north and south soffits (Fire Zones 0-26M and 0-26R).

Deviation Request No. 37 was issued and,subsequently approved by. an SERjustifying that the fire protection features provided under the Control Room raisedfloor and cable chases and cable shafts as described in the deviation request areadequate for the existing cable installation and provide an equivalent degree ofsafety as required by Appendix R. The, deviation request concluded that theaddition of raceway wrapping and fully-automatic fire suppression systems in FireAreas CS-9 to meet the requirements of 10CFR50 Appendix, R, Section III.G.2would not significantly increase the level offire protection in these fire areas.

Another potential concern for the non-safe shutdown division of the RHR Systemwho'se.circuits are not isolated from the main Control Room is inadvertent anduncontrolled injection'nto the RPV. By assuming a number of independentspurious operations on these RHR System components, a vessel overfill conditioncould be postulated. Should this condition occur, however, it would not-occur

" until the RPV was at low pressure and safe shutdown could still be accomplishedby further depressurizing'the RPV with'the SRV's available at the. RSP,

using'HR

in the LPCI mode and, ultimately, using,RHR in'the Alternate Shutdown,Cooling mode. Any excess water flow from the Core Spray System resulting fromthis condition could be integrated with the shutdown approach described abovewith no impact to safe shutdown.

C

Therefore, adequate measures are in place to mitigate against the potential for, andconsequences of, a possible fire in the Control Room from impacting the RHRcables that are not isolated.

7.3.17 RHRSW

The Unit 1 and Unit 2 Residual Heat Removal Heat Exchanger Service WaterValves HV-11210B and HV-11215B (Unit 1) and HV-21210A and HV-21215A(Unit 2) are Appendix R Path 2 Safe Shutdown components that=must have thecapability of being operated outside the Control Room. For a fire in the Control '

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Room, these valves are provided with control capability at the Remote ShutdownPanels 1C201B and 2C201B to support RHR Shutdown Cooling.

In the original design, all of the "control circuitr'y for these valves from the ControlRoom could be isolated at the RSP except for the thermal overload bypasscircuitry to Control Room Panel OC697. In the event of a fire in the ControlRoom, the cable for the bypass circuit could have short circuited to ground causingthe valve's control circuit fuse to blow which would have compromised theoperability of the valves at the RSP.

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DCPs 88-3017E and 18E, added isolation circuitry to valves HV-.11210B and HV-11215B and HV-21210A and HV-21215A thermal overload bypass circuitry toassure the control capability of the valves at the RSP during an Appendix R Path 2shutdown. Thus, a fire in the Control Room willnot impact the ability to operatethese valves from the RSP to support Path 2 safe shutdow'n..

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7.3.18 RRS

In order to support. Path 2 Safe Shutdown in the event of a Control Room fire, theReactor Recirculation Pumps are required to be automatically or manually trippedprior to pla'cing RHR into the Shutdown Cooling mode.

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A. Two cables, one for each of the Unit 1 and 2 Reactor Recirculation Pumps .

. (1P401A and 1P401B) are routed in cable shafts under the north and southsoffits-(Fire Zones 0-26M and 0-26R) ofFire Area CS-9.

Deviation Request No. 37 was issued and subsequently approved per an SERjustifying that the fire protection features provided under the control room„,raised floor and the cable chases and c'able shafts are adequate for the existingcable installation and provide an equivalent degree of safety as required byAppendix R. The deviation request concluded that the addition of racewaywrapping and fully-automatic fire suppression systems in Fire Areas CS-9 tomeet the requirements of 10CFR50 Appendix R, Section III.G.2 would notsignificantly increase the level offire protection in thes'e fire areas.

B. A fire in the Control Room (in Fire Zone 0-26H) could damage-certain cablesfor the Units 1 an'd 2 Reactor Recirculation Pumps resulting in the inadvertentspurious operation of the respective pump(s). In,the unlikely event of thisoccurrence, Procedure 'ON-100/200-009 requires an operator to trip

the'eactorRecirculation Pumps motor generator set (2 per unit) locally at therespective 13.8KV.cubicles for the drive motors. This ensures that a fire in the .

Control Room that results in the, spurious start of the RRS pumps can betripped. manually thereby preserving Safe Shutdown Path 2 functionality.


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7.3.19 Standby Liquid Control

The, postulated concern for the Standby Liquid Control system circuits that are notisolated from the main Control Room is the inadvertent and uncontrolled injectioninto the RPV resulting in a vessel overfill condition at high pressure. Thiscondition would result in an injection rate of less than 100 gpm. The available .

quantity offlow from this system is also limited to the inventory in the SLC Tank.An injection rate of this magnitude would allow'greater than 30 minutes for theoperator to respond. The operator would respond by taking control of the unit atthe RSP. The impact of inadvertent SLC injection would be mitigated bythrottling back. on the RCIC injection rate at high pressures and the,RHR SDCinjection rate at low pressures. Therefore, 'inadvertent injection by the SLC systemwillhave no impact on safe shutdown.

7.3.20 SPM

Suppression pool temperature monitoring for the remote shutdown panels isprovided by the SPM System for each unit. While two redundant divisions of thesystem are provided for e'ach unit and displayed at the units remote shutdownpanel, there is a possibility that cable failure induced by a Control Room fire couldresult in the loss of suppression pool temperature indication at the remoteshutdown panels.

In the event that both divisions of suppression pool temperature indication at theremote shutdown panel fail, alternative indirect„methods are available andacceptable to provide suppression pool temperature status. Suppression pooltemperature can be inferred from suppression chamber atmosphere temperatureand atmosphere pressure indication which are available at the remote shutdownpanel. Because the chamber remains a relatively constant volume, the pool heat-upor cooldown rate willbe related to these two air parameters.

Deviation Request No. 2 was issued and subsequently accepted by the NRC in anSER justifying the acceptability of utilizing the alternative means. of monitoringsuppression pool temperature. Therefore, no further action is necessary.

7.3.21 SRVs

In the event of a fire in a Control Room fire zone requiring evacuation and plantshutdown from the Remote Shutdown Panels, a SRV is required to be

opened'ntermittentlyper Calculation EC-013-0845 (Reference 6.2.3) while the remainingADS/SRVs are required to remain closed. For this Path 2 shutdown method, oneout of three SRVs willbe cycled to open and close manually by the operator at theRemote Shutdown Panel in order to depressurize the reactor vessel whilemaintaining sufficient steam pressure supply to the RCIC pump turbine.


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A fire-induced cable failure resulting in the spurious opening of one SRV has been

determined to have an insignificant affect on the steam supply to the.RCIC pumpturbine. In addition to this, symptom based Procedures EO-100-102 and

EO-100-'12,

require the operator to open additional SRV valves should this be necessary

to depressurize the reactor to allow the use of low pressure injection systems.

This can be accomplished by depressurizing using an ADS/SRV controlled by an

individual keylock switch in the relay room. The individual keylock switch circuitsin'the r'clay rooms are independent of the 'Control Room and will function

'egardless of fire damage in the Control Room. Procedures. ON-100-009 and ON-200-009 provide the direction for an operator to manually control the ADS SRV'sfrom the relay rooms.'

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Fire Ar Evaluation for: CS-9Required Shutdown Path: 2

Appe dix AControl Room Appendix R Compliance Report

Dat . /10/29Page 9

S stem.'ffected

Unit .- Com onent „'::,CableFire

Zone Dis osition:,.Analysis"-

Documen't;-Dispositioning:.,

Do'cument":.:'.'LOWDIV

HV01120C

HV01120DHV01122AHV01122BHV01122C

HV01122D1 HV1 5766

HV1 5768

CKOS0417C

DKOS0419CAKOS0405CBKOS0407CCKOS0409C

DKOS0411CEK1EC5101EK1 Q403?K

EK1 Q4169CEK1 Q4169FFK1EC5208FK1 Q0628GFK1 Q4170C

0-26G Circuit modified to provide isolation from Control Room0-26H Circuit modified to provide isolation from Control Room0-26M Circuit modified to provide isolation from Control Room0-26H Circuit modified to provide isolation from Control Room0-26H Circuit modified to provide isolation from Control Room0-26H Circuit modified to provide isolation from Control Room0-26G Circuit modified to provide isolation from Control Room0-26H Circuit modified to provide isolation from Control Room0-26M Circuit modified to provide isolation from Control Room0-26H Circuit modified to provide isolation from Control Room0-26H Operator Action Required0-26H Operator Action Required0-26N Operator Action Required0-26H Operator Action Required0-26H Operator Action Required0-26H Operator Action Required0-26H Operator Action Required0-26H Operator Action Required

Appendix BAppendix BAppendix B

Ap endixBAppendix B

Appendix B

Appendix B

Appendix B

Appendix B

Appendix BEC-013-0725EC-013-0?25EC-013-0725EC-013-0725EC-013-0725EC-013-0725EC-013-0725EC-013-0725

DCP 88-3016IDCP 88-3016IDCP 88-30161DCP 88-30161DCP 88-30161DCP 88-3016IDCP 88-3016IDCP 88-3016IDCP 88-3016IDCP 88-30161ON-100-009ON-1 00-009ON-1 00-009ON-1 00-009ON-1 00-009ON-100-009ON-1 00-009ON-1 00-009

FK1Q4170FHVB211F001 EK1 Q160?CHVB211F002 FK1 Q1608CHVB211F016 EK1P62204HVB211F019 FK1P62315HVG331F001 EK1P64202HVG331F004 FK1 P6F202

0-26H Operator Action Required0-26H Willnot impact shutdown0-26H Willnot impact shutdown0-26H Spurious valve operation will not impact shutdown0-26H Spurious valve operation will not impact shutdown0-26H Modified HV-G33-1F004 circuitry to ensure operability0-26H Modified HV-G33-1F004 circuitry to ensure operabili

EC-013-0725Appendix B

Appendix BEC-013-0964EC-013-0964Appendix B

Appendix B

ON-1 00-009GO-1 00-002GO-1 00-002ON-1 00-009ON-1 00-009DCP 88-3017FDCP 88-3017F

FLOWDIV 2 HV25766

HV25768

EK2E0002A

EK2Q4037KEK2Q4169CEK2Q4169FFK2E0014AFK2Q0628GFK2Q4170CFK2Q4170F

0-26H Operator Action Required0=261 Operator Action Required0-26R Operator Action Required0-26H Operator Action Required0-26H Operator Action Required0-26H Operator Action Required0-26H Operator Action Required0-26H Operator Action Required0-26H Operator Action Required0-26H Operator Action Required

EC-013-0725EC-013-0725EC-013-0725EC-013-0725EC-013-0725EC-013-0725EC-013-0725EC-013-0725EC-013-0725EC-013-0725

ON-200-009ON-200-.009ON-200-009ON-200-009ON-200-009ON-200-009ON-200-009ON-200-009ON-200-009ON-200-009

HVB212F001 EK2Q160?CHVB212F002 FK2Q1608CHVB212FO'I6 EK2P0178A

0-26H Willnot impact shutdown0-26H Redundant valve is available0-26H Spurious valve operation will not im act shutdown

Appendix BEC-013-0725EC-013-0964

GO-200-002ON-200-009ON-200-009

APPENDIX C

RESOLUTION. OF THE MOV"HOT SHORT" ISSUE

NRC INFORMATIONNOTICE 92-18

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1.0 Purpose: .

The purpose of this calculation is to document the final disposition of the MOV"HotShort" issue described in NRC Information Notice (IN) 92-18, Potential for Loss ofRemote Shutdown Capability During a Control Room Fire.

The resolution ofthis issue for SSES is possible due to the redundancy provided in Path 2,. the safe shutdown path used to mitigate the effects offires in the main Control Room..

The normal line up expected to be 'used for the Control Room fire scenario is to use RCICfor vessel make up, to use RCIC assisted by SRV's to control the reactor pressure,'to useRHR Suppression Pool Cooling during the time when steam is being dumped into theSuppression Pool and to use RHR'in the Shutdown Cooling mode after the reactor hasbeen depressurized to less than 98

psig.'hould

a single hot short damage any one of the valves required'for this expected line up,the following options are available using the equipment and procedures provided at theRemote Shutdown Panel

~ IfRCIC is lost, then reactor pressure can be quickly reduced to the level whereinjection using RHR in the LPCI mode is possible.

~ Ifthe normal RHR Shutdown Cooling mode is lost, then RHR can be used in the, Alternate Shutdown Cooling mode.,

~ IfRHR Suppression Pool Cooling is lost, the RHR in the Alternate Shutdown Coolingmode can be used.

This calculation uses the redundancy available in Path 2 to determine the minimum numberofPath 2 valves that must be protected from a hot short occurring and damaging the valveprior to transfer ofcontrol to the Remote Shutdown Panel. By preventing damage to thisminimum set ofvalves, it willbe assured that the requirements ofAppendix R can be meteven ifa damaging hot short were to occur.

2.0 Description ofProblem: .* 'I

The postulated condition ofconcern is that a fire in the Control Room can cause "HotShorts", i.e. short circuits between control wiring and power sources, for certain'motor-operated valves (MOV's) needed to shut the reactor down and'to maintain it in a safe .

condition. Ifa fire in the Control Room forces the operators to leave the Control Room,'these MOV's can be operated from the Remote Shutdown Panel (RSP). Hot Shorts,combined with the absence of thermal overload protection, however, could cause valvedamage before the operator has actuated the transfer switches and taken control of thesevalves at the'RSP.

EC-013-0859Page /~y

Thermal overload protection for MOV's at SSES is bypassed in order to meet therequirements ofRegulatory Guide 1.106, Thermal Overlo'ad Protection for ElectricMotors on Motor-Operated Valves. The intent ofthis requirement is to,assure thatthermal overloads do not prevent the MOV's from performing their safety-function duringan accident. At SSES, the location of the thermal overload contacts in the MOVcontrolcircuitry would be ineffective in mitigating the effects ofhot shorts even'f the thermal

'verloads were not bypassed.

/Similarly, the'location in the MOVcontrol circuitry of limit switch and torque. switchcontacts renders these protective devices ineffective in mitigating the effects ofMOV hotshorts.

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3.0 Background:f

The initial approach to address this'issue was to identify those MOV's required to supportsafe shutdown for Control Room fires and to determine which were susceptible to thepostulated failure mode. The information'related to this step was compiled in CalculationEC-013-0730, This calculation determined that,39 valves on Unit 1 and 40 valves on Unit2 that were required to support safe shutdown were susceptible to the postulated MOVfailure mode.

, Those valves determined to be susceptible to damage due to hot shorts were slated for amodification to relocate the torque and limit switches to a location within the controlcircuitry where they would be effective in interrupting a hot short due to a Control Room

'ire and preventing valve motor damage:

Since the original circuit review of the affected valves determined the valves did not havea sufficient number of spare conductors to accomplish the required circuit changes, newcable would have to be run for many of these valves. This significantly escalated the costof the work. The total cost for all of this work was estimated to be approximately $8.0million.

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Due to the large cost of resolving this issue using physical modifications, additionalevaluations were determined to be required to assess the safety significance of this issue.Two calculations, were prepared to hssess the safety significance of this issue. Calculation

'C-013-0983 performed a risk analysis of the MOVHot Short issue. The results of this.calculation and the fire hazards analysis'documented in Calculation EC-013-0555determined that the safety significance of this issue was extremely small. Based on theseresults, Deviation Request No. 41 was prepared and issued to the NRC on June 21, 1993as an attachment to PLA-3980.

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In early 1995, the NRC verbally requested some clarifications on the informationcontained in Deviation Request No. 41. The response to this NRC request for additionalinformation was transmitted to the NRC by PPkL in PLA-4341 dated August 2, 1995.

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In a meeting on January 25, 1996 with the NRC in Allentown, the NRC informed PPEcLthat they would be rejecting Deviation Request No. 41; Their reasoning was that otherutilities had already dealt with this issue successfully without incurring significant costs.

. This calculation provides the final resolution for this issus for SSES.

Based on a series ofdiscussion with the NRC, a revised spurious operations. criteria forAssociated Circuits was developed. This criteria was transmitted to the NRC in PLA-

- 4505. This criteria has been applied in the evaluation contained in this appendix of theimpact ofMOV"Hot Shorts" resulting from Control Room fires.

4.0 Results and Conclusions: ~

This calculation evaluates the list ofpotential problem valves with respect to the MOVhotshort issue as documented in Calculation EC-013-0730 and performs a system evaluationof the valves and determines for each of the valves which other valves, must be able to beoperated in order to achieve and maintain safe shutdown for a Control Room fire.

Table 1 provides a summary ofthe disposition for each valve on Unit 1. Table 2 providesa summary of the disposition for each valve on Unit 2. For each of.the valves identified inTables 1 and 2 that required some mitigating action to preclude an impact to safeshutdown capability, a review of the possible solutions for each valve was performed.

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Table 3 provides a summary of the potential solutions for each of these valves. Table 4provides a summary of the recommended solution for each valve.

Calculation EC-013-0730 identified 39 problem valves for Unit 1 and 40 problem valv'esfor Unit 2. The system review documented within this appendix has reduced the numberofproblem valves to 12 for Unit 1 and 12 for Unit 2. Ofthese 24 valves, the modificationreview performed in this calculation has determin'ed that all ofthese valves can

be'odifiedto mitigate the effects ofMOV hot shorts by making wiring adjustments withoutrunning new cables. The preferred solution for each of these valves is to installinterposing relays, since this solution eliminates the potential for damaging hot shorts forall fires except those occurring in the MCC.

4

The option oF relocating the torque and limit switches solves the problem for the fire in themain Control Room, but creates a susceptible condition for fires elsewhere in the plant.Should the torque and limit switch relocation option be the only feasible option, for aparticular MOV, the potential for a hot short in other areas of the plant causing valvedamage must be investigated and it must be determined that such damage willnot impact

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EC-013-0859 .

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~ the ability to achieve and maintain safe shutdown. This evaluation is to be conducted as a

part of the engineering performed for each valve modification.

5.0 References:,

5.1 Calculation EC-013-0730, Rev..0, Appendix R Safe Shutdown Path 2 MOVHotShort Spurious Actuation.

5.2 Calculation EC-013-0555, Rev. 1, Appendix-R Hot Shorts, in the Control Room.

5.3,Calculation EC-013-0983, Rev. 0, Risk Analysis ofAppendix R MOVHot ShortModifications.

5.4 Calculation EC-013-0725, Rev. 2, Evaluation ofthe Containment Instrument GasValves and Suppression Pool Clean-up Valves,

5.5 Calculation EC-VALV-1043, Rev. 0, MOVEvaluation for Spurious Oper'ation due toHot Short

5.6 PLA-3980 dated June 21, 1993 transmitting Deviation Request No. 41.I

5.7 PLA-4341 dated August 2, 1995.

5.8 PLA-4505 Associated Circuits- Spurious Operation Issue.

6.0 Disposition Discussion:

6.1 Assumptions arid Requirements:

.6.1.1. Safe Shutdown as a result offires in the main Control Room is classified asAlternate Shutdown. As such, the requirements of 10CFR50 Appendix R Section III.Lapply-

6.1.2. For fires in the main Control Room Section III.Lrequires that spurious operatioq ofequipment that can affect safe shutdown functions be considered. The spurious operationcriteria for circuits isolated from the main Control Room is contained in NRC GenericLetter 86-10 paragraph 5.3.10. That criteria reads as'follows:

~ The safe shutdown capability should not be adversely affected by any one spuriousactuation or signal resulting from a fire in any plant area; and

~ The safe shutdown capability should not be adversely affected by a fire in any plantarea which results in the loss ofall automatic function (signal, logic) from the circuits

EC-013-0859Page /~~

located in the area in conjunction with the one worst case spurious actuation or signal ~

resulting from the fire; and~ The safe shutdown capability should not be adversely, affected by a fire in any plant

area which results in spurious actuation of the redundant valves in any one high-lowpressure interface line.

For application of this criteria for all situations other than Hi/Lo pressure interfaces, it is. assumed that one spurious operation occurs prior to actuating the transfer switch at the

RSP., This spurious operation ma'y be as a result. ofa hot short on a circuit that is isolate'd

from the main Control Room or on one that is not: It is not necessar'y to postulatespurious operation ofequipment in each of the'se two categories: i.e isolated and non-isolated circuits.

For circuits remaining in'he main Control Room that are not isolated, all potentialspurious operations must be addressed on a one-at-a-time basis. Each individual spuriousoperation inust be identified and a mitigating action to prevent an impact to safe shutdownmust be developed. In developing this mitigating action, however, it is not acceptable toignore a potential hot short on one piece of equipment as a mitigating action for anotherpiece ofequipment.

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The act ofactuating the transfer switch at the RSP is the mitigating action to address anyspurious operation for circuits isolated from the main Control Room. For circuits notisolated form the main Control Room, some other means ofmitigiting the effects of thepotential spurious operation must be'available.

6.1.3. This appendix addresses the additional mitigating actions necessary to assure that. MOVdamage as a result ofhot shorts willnot prevent achieving safe shutdown using the

systems and components described in the body of this calculation.

6.2 Additional Mitigating Actions for A'ssuring Safe Shutdown: '

6.2.1. The MOV's impacted by this issue are listed in Table 1 for Unit 1 and Table 2 for-Unit 2. The MOV's listed pertain to the following systems and perform the followingfunctions in support of safe shutdown'...

~ RCIC- performs the RPV pressure control and inventory make-up functions.~ RHR- performs the decay heat removal function.~ RHRSW/ESW- performs the decay heat removal function.~ Suppression Pool Drain valves- one of these two series valves must remain closed to

prevent a flow diversion from the suppresion pool that could affect the RPV inventorycontrol function and decay heat removal function.

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~ Reactor Recirc. Pump Suction Valve- this valve must be closed prior to enteringshutdown cooling to prevent short-cycling ofthe shutdown cooling flow.

~ Reactor, Water Clean-up Valve- this valve must be closed to prevent a loss ofRPVinventory through the RWCU line'to either Liquid Radwaste or the Condenser.

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Should these primary safe shutdown capabilities be affected by MOViHotShorts that~ damage the equipment, there are other available modes ofoperation allowed for the

~ systems listed above. For example, the SRV provided at'he RSP can'perform thepressure control function described'for RCIC above and RHR can perform the inventory'.make-up function described above for RCIC.

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This calculation willdemonstrate how these redundant capabilities willbe used to mitigatethe effects ofMOVhot shorts. Through the use of these redundant capabilities, thiscalculation willdemonstrate how compliance with Appendix R is achieved.

6'.2.2. RCIC System Valves: The valves listed in tables 1 and 2 related'to the RCICsystem could be damaged as a result of the postulated phenomenon. Ifany one of thesevalves i's damaged, RCIC may not be available for use at the RSP. This would impact theRPV pressure control and inventory make-up safe shutdown functions.

Ifthis were to happen, however, the reactor could be depressurized using the availableSRV's at the RSP and vessel inventory make-up could be accomplished using RHR in theLPCI mode. By using RHR in the alternate shutdown cooling mode in accordance withON-149/249-001, Suppression Pool Cooling can be accomplished using the same flowpath. See Figure 1A attached for the Unit 1 flow path and Figure 1B attached for the Unit2 flow path.

Prior to entering Alternate Shutdown Cooling, ON-149/249-001 requires that the. mainsteam drain line valves be closed. Calculation EC-083-0530, Effect ofFlow DiversionThrough the Open Main Steam Line Drains, determined that these valves would berequired to be closed within 10 hours of entering Alternate Shutdown Cooling to preventan adverse impact to Suppression Pool level. Since the main steam line drain valves'arenormally open, but are required closed and these valves could be prevented from.automatically closing by the Control Room fire, these valves may be required to b'

manually closed locally.

Since this action is not required for a minimum of 10 hours after the start of the event-, 8hour battery powered emergency lights would not be effective in aiding the operator. Dueto the presence ofdiesel backed essential lighting in the general area that is unlikely to be'

damaged by a Control Room fire and due to the simplicity of the required action, hand-held lighting typically carried by the operator is considered to be adequate for this action.

EC-013-0859Page .~'-,">+ ~

Therefore, damage to any of the valves listed in tables 1 or 2 related to the RCIC systemwillnot impact the ability to achieve or-maintain safe shutdown of the reactor. Therefore,no further action needs to be taken for'these valves.

\

6.2.3. RHR System Valves: As stated in Section 1 of this appendix, impacts to the RHRsystem can be mitigated by relying on RHR Alternate Shutdown Cooling where normalshutdown cooling and suppression pool cooling is impacted or by relying on RCIC when

'impacts to the main RHR flow path valves are impacted:

6.2.3.1. HV-151-F008/009 and HV-251-F008/009: These valves are the shutdowncooling containment isolation valves. By relying on RHR Alternate Shutdown Cooling,these valves which normally must open to establish a,flow path fo'r normal shutdowncooling are only required, for this scenario, to remain closed and to prevent a Hi/Lopressure interface flow diversion from the reactor.

A"review of the electrical schematics for these valves has determined that a hot short in themain Contr'ol Room cannot cause the spurious opening ofHV-151-F008/009 or HV-251-F008/009. This is true because of the location of'the contacts for the low pressurepermissive for these valves. Within the circuit, these contacts, which are physically

"

located in the reactor building, are located below the hot short location and would, .

therefore, prevent the spurious opening ofthe valve until,the reactor pressure was lessthan 98 psig. Prior to reaching 98 psig, the transfer switches at the RSP would have beenactuated and spurious operation would be.

prevented.'amage

to any ofthese valves willnot impact the ability to achieve or maintain safe— shutdown of the reactor. Therefore, no further action needs to be taken for these valves.

6.2-.3.2. HV-151-F006A/B/C/D and HV-251-F006A/B/C/D: These valves are theshutdown cooling pump suction valves. They are normally closed. By relying on RHRAlternate Shutdown Cooling, the need for these valves can be i'educed: For this scenario,these valves must remain closed. Therefore, the only. concern is flow diversion from theRHR flow path, since the F008 and F009 valves remain closed in RHR Alternate =

Shutdown Cooling.,I

On unit 1, the F006B valve can be operated at the RSP. On unit 2; the F006A.valve canbe operated at the RSP. Allvalves (F006 A/B/C/D for each unit) are electrically isolatedfrom the Control Room by transfer switches at the RSP.

Since the criteria ofGeneric Letter 86-10 paragraph 5.3.10 requires the as'sumption ofany~ one spurious operation for circuits that are isolated from the main Control Room, it must

be assumed that only one of these valves spuriously operates. Ifthe F006B on unit 1 wereto spuriously open, flow diversion from the RHR flow path would be prevented by the

*

EC-013-0859,

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combined eFect of the F006A, C, D and the F008 valves. Therefore, spur'ious operationof, the F006B valve is not a concern.,

Ifeither the F006A, C or D valves were to spuriously open,'he F006B on unit 1 wouldremain closed and prevent a flow diversion from the RHR flow path. Therefore, spuriousopening of any of these valves is not a concern..

The situation on unit 2 is identical for the F006A valve

Damage to any one of these valves willnot impact the ability to achieve or maintain safeshutdown of the r'eactor. Therefore, no further action needs to be taken for these valves.

6.2.3,3 HV-151-F024B/028B and HV-251-F024A/028A: These valves are theSuppression Pool Cooling'return line isolation valves. These valves are normally closed.Ifeither of these valves were to be damaged by an MOVHot Short, RHR SuppressionPool Cooling would be impacted.

t.*

The loss ofSuppression Pool Cooling, however, can be mitigated by the use ofRHR inthe Alternate Shutdown Cooling mode ofoperation by taking suction on'the SuppressionPool through the F004 valve and routing the flow through the RHR heat exchanger. Assuch, the Suppression Pool Cooling return valves are only required to remai'n in theirnormally closed position to prevent flow diversion from the RHR flow path.

Since both of these valves and the HV-151-F027B'and the HV-251-F027A valves on unit1 and 2, r'espectively, are isolated from the main Control Room by transfer switches, flowdiversion due to a sihgle spurious operation is not possible.

Damage to any, one of these valves willnot impact the ability to achieve or maintain safe '„

shutdown of the reactor. Therefore, no further action needs to be taken for these valves.

6.2.3.4. HV-151-F007B and HV-251-F007A: These valves are the RHR Pump minimumflowvalves. They are normally open. They are desired open until RHR flow reachesapproximately '2400 gpm.

Ifa spurious operation result in the inability to close, these valves,'this willdivertapproximately 1000 gpm fiow from the RHR flow path. This willnot impact safeshutdown since approximately 9000 gpm willstill be available. This amount offlow is

'ufhcient to support shutdown. The diverted flowwill return to the Suppression Pool.'h

f

Ifa spurious operation results in the inability to open this valve, this could a6ect theoperator's ability to slowly fillthe RHR discharge piping should the LOOP,,which must be

, postulated as a part.of this Appendix R scenario, result in a system draindown due to lossofkeepfill. The operator, however, can still accomplish the sloC fillingof the discharge

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piping, required as a mitigating action to deal with the loss ofkeepfill, without damagingthe pump provided he throttles opens the F048 valve shortly after starting the pump.

II

Damage to these valves willnot impact the ability to achieve or maintain safe shutdown ofthe reactor. Therefore, no further action needs to be taken for these valves.

6.2,3,5. HV-151-F016B and HV-251-F016A: These valves are the normally closed,, outboard Containment isolation valves for the Unit 1 division IIand Unit 2 division I RHR

Containment Spray System.- The inboard Containment isolation valves are HV-151-F021B on unit 1 and HV-251-F021A on unit 2 are normally closed. valves. Only the F016valves are isolated from the main Control Room by transfer switches at the RemoteShutdown Panel. When the. transfer switch for the F016 valves are actuated at the RSP, aclose signal is given to the valve. In addition, the open and close control circuits from themain Control Room are isolated. Since the F021 valves are not isolated from the mainControl Room, they are considered to be vulnerable to hot shorts occuring'after theactuation of the transfer switches at the RSP.

Ifthe F016 valve were to spuriously open and be damaged by a hot short that drives themotor to failure, the ability to close the valve willno longer be available at the RSP.RCIC would still be available to provide vessel make up. Should the F021 valve, which isnot isolated frotn the main Control Room, subsequently spuriously open, then a flowdiversion from the RHR flow path for'ither Suppression Pool Cooling or ShutdownCooling to the RHR Drywell Sprays could occur..With respect to the flow diversion fromthe RHR Suppression Pool Cooling flow path, suppression pool cooling could still beaccomplished since the water would flow from the drywell sprays to the diaphr'agm slabelevation through the downcomers and into the suppression pool. In the case of the RHR

, Shutdown Cooling flow path, however, this flow diversion could result in a drain down ofthe reactor vessel to the suppression pool.

To prevent this undersireable consequence, the ability to close the F016 valve. must be

preserved by eliminating the potential for a hot short to damage the valve. This willpreserve the ability to close the F016 valve from the Remote Shutdown Panel. As long asthis valve is closed prior to entering RHR Shutdown Cooling, the negative consequencesassociated with a spurious opening of the F016 and F021 valves willbe averted.

Therefore, a modification must be perform'ed to prevent'damage to the 1F016B and2F016A valves. I

6.2.3.6. Remainin RHR S stem Valves F003'004'015 F017'047'048: Theremaining valves on the RHR system are required to be capable ofbeing operated toestablish the Alternate Shutdown Cooling flow path for RHR.' single spurious operation

, ofany one ofthese valves would prevent the use ofRHR in either the Suppression PoolCooling, the LPCI or the Alternate Shutdown Cooling modes ofoperation. That is, all

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five valves are required to be available to support operation ofthe system for Decay Heat

~

~

Removal or low pressure make-up.'f

the single spurious operation, however, were postulated to occur on one of these valves,'RCIC operation would still be available. Therefore, the vessel inventory make-up function

= would be addressed. As such, some time:would be available to correct the condition—either by manually repositioning the valve or by some other corrective action. The time

. available would be the amount of time before RHR must be placed in Suppression PoolCooling to remove the heat being placed in the pool by RCIC operation.

At the RSP, RCIC has the capability of taking suctio'n from either the Condensate StorageTank or the Suppression Pool. When taking suction from the Suppression Pool, RCICcan operate for approximately 4 hours before the pool temperatures willreach the levelwhere potential damage to the pump could occur. At this point ifthe operators were to-transfer suction to the Condensate Storage Tank, there would be a minimum of„6.5 hoursofoperation ifthe CST were at its minimum Tech Spec level. Therefore, there would beapproximately 10.5 hours available to manually open any valve that might be spuriouslyclosed by a Control Room fire hot short.

Therefore, damage to these valves must be prevented so that they may be either manuallyopened or operated at the RSP to support RHR system operation".

k

6.2.4 RHRSW/ESW System Valves: The RHRSW valves required for safe shutdownare the RHR Hx inlet-and outlet valves: HV-11210B and HV;11215B; HV-21210A andHV-21215A. These valves must be open to allow RHRSW flow through the RHR"Hx.

The ESW valves required for safe shutdown are the spray pond return valves: HV-'1222B and HV-01224B1; HV-01222A and HV-01224A1. The 22A/B valves for the

bypass return line are normally open and must close in this scenario. The 24A1/Bl valvesare normally closed and must open for this scenario. Since the diesel generators must beavailable for the Control Room fire, ESW must also be available to provide cooling to thediesels. Due to the short time duration the the diesels can run without cooling(approximatelt 4-5 minutes), local manual operation ofthese valves may not be feasible.

J

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Spurious closure ofeither valve on a given unit willafFect the decay heat removalcapability of the RHR System. Therefore, damage to these valves must be prevented sothat they may be oper'ated either at the RSP or by manual means locally to supportRHRSW/ESW system operation.

6.2.5. Suppression Pool Drain Valves: The Suppression Pool Drain Valves are theContainment Isolation Valves for the system: HV-15766 and 15768; HV-25766 and HV-25768. These'valves are normally closed and one valve in each line must remain closed'toprevent a flow diversion from the Suppression Pool. These valves are not isolated from

EC-013-0859Page/<S h'

the Control Room. A flow diversion from the Suppression Pool is,only possible in twoways.

One is ifCondenser vacuum is established and the normally closed manual ball valve,157310 on Unit 1 and 257310 on Unit 2 is open and valves HV-1/25766/68/69 allspuriously open. Without Condenser vacuum, the piping configuration provides a loopseal that willallow only 15" of level to drain from the Suppression Pool. With the manual,

. ball valves closed, flow to the condenser is prevented.,

The other way is by spurious opening ofHV-15766/68/69 on Unit 1 and HV-25766/68/69on Unit 2 which could result in a flow diversion to Liquid Radwaste.

A drain down ofthe Suppression Pool could affect the performance ofECCS Pumps (i.evortex limits).

/Calculation'EC-013-0725 has demonstrated that, should these valves simultaneously opendue to a spurious signal, it willtake a minimum of 10 hours before a drain down willreacha level that willaffect pump vortex limits. Therefore, an operator action must beperformed within this time frame to close the 157025 valve on Unit 1 and the 257025valve on Unit 2 ifSuppresion Pool level begins to decrease for an unknown reason. Thesevalves were selected since they are manual valves that willnot be affected by ControlRoom hot shorts.

6.2.6. Reactor Recirc. System Valves: The Reactor Recirc. valves used for safeshutdown are the pump suction valves: HV-143-F023B; HV-243-F023A and HV-243-F023B. These pump suction valves must close to prevent short-cycling of the ShutdownCooling Flow. The F023A valve's not on the RSP. Allof these valves are inside ofprimary containment. Therefore, local manual operation is not feasible.

On, unit 1, division 2 is used for shutdown. As such, Shutdown Cooling suction anddischarge uses the B Recirc. Loop. On unit 2,'owever, division 1 is used for shutdown.As such, Shutdown Cooling suction uses the A loop while Shutdown Cooling'discharge isthrough. the B loop. Therefore, on unit 2, both pump suction valves must be'closed fornprmal shutdown cooling. For Unit 2, however, if Alternate Shutdown Cooling usingRHR is the selected safe shutdown path, then the 2F023B valve cannot cause a short.cycling of the flow.

An inability to close HV-143-F023B on Unit 1 and HV-243-F023A willaffect the decayheat removal capability of the RHR System. Therefore, damage to these valves must beprevented so that they may be closed either at the RSP or by a local operator action at an

'

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6.2.7. Reactor Water Clean-up'Valves: The Reactor Water Clean-up system must be,isolated from the RPV in order to assure a flow'diversion to either liquid radwaste or theCondenser does not occur. To prevent this for the fire jn the main Control Room, anoperator action has been included in ON-1/200-009 to open a breaker to close valve HV-

'44-F033on unit 1 and HV-244-F033 on unit 2. (Reference Drawing E"-690).I

a

6.3. Options for Resolution: The valves listed in Table 3 are the minimum set of Path 2, motor operated valves required to achieve and maintain safe shutdown for a control roomfire which have the potential for spurious operation as a result of a hot short. With a hotshort in the control room, the protective features of the limit switches and torque switches

'or

the valve and the motor operator are bypassed.'he standard motor operated controlcircuit design for these valves is shown in Figure 2. Two standard designs are shown.The specific design for the valve is dependent on whether or not the motor operator has alocking type worm gear for the torque switch.

In order to achieve safe shutdown, operation of these motor operated valves either at theremote shutdown panel or locally for the postulated hot short scenario must be assured.Operation of these valves can be assured by,demonstrating the feasibility of an operatoraction'or by one of the following modifications listed above and described below. Theevaluation to determine the feasibility of opening the valves using the handwheel isdocumented in Calculation EC-VALV-1043.

For those valves which have existing interposing relays in the control circuitry, the controlroom logic continues to energize the interposing relays and the limitswitch and torqueswitch contacts are rewired into contactor portion of the circuitry so that the postulatedhot short, does not negate the protection of the valve or motor operator. The'rewiring isshown in Figure 3. For those valves which do not.have the feature of the locking wormgear, there is a spare conductor in the, cable from the motor control center to the valveoperator. The spare conductor permits the limit and torque switches to be rewired intothe control circuitry between the control room contacts and the open and close'coils of thecontactors so that the valve and motor operator protection is functional for the postulatedhot short. The rewiring is shown in Figure 4. For those valves which do not have existinginterposing relays or a spare conductor, in the cable(s) from the motor control center to themotor operator, interposing relays may be added to the control circuitry so'that thecircuitry is as shown in Figure 3...

In performing the review documented in EC-VALV-1043, the Nuclear Technology- ValveGroup determined that all afFected valves are locking valves. The'electrical circuitryshown on the valve schematics that would be typical ofa non-locking valve is not requiredfor these valves. Therefore, all affected valves-may have spare conductors that can

be'sed

to relocate the torque and limit switches provided the 42F contact in the circuit is notperforming another function.

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6.4; Recommended Solution: The recommended solution for each ofthe valves is toinstall interposing relays. This solution is recommeded because it best eliminates theproblem. The solution of relocating the torque and limit switches solves the problem for

'he

Control Room, but leaves open the possibility for the same problem in another area ofthe plant.

1

The range of solutions examined for each valve are listed in Table 3. The solution that can'. be accomplished, ifthe recommended solution of installing interposing relays is

determined to not be feasible due to spatial limitations, is summarized in Table 4. Ifthesolution in Table 4 ofrelocating the torque and limit switches is selected, an Appendix Rreview of the new configuration must be performed to verify that the circuit modificationdoes not result in an unacceptable Appendix R non-compliance elsewhere.

I

There are a total of24 valves listed in Table 4. 12 of these valves are associated with eachunit. For all of the valves, the circuit changes necessary to mitigate the sects'of ControlRoom MOVhot shorts can be accomplished using the existing cables by rewiring thecircuits. The following summarizes the types ofchanges-available for this population ofvalves:

I

Torque/Limit Switch Relocation:

9 valves have spare conductors in the existing cable running from the MCC to thevalve. This willallow the relocation of the Torque/Limit Switches as depicted inFigure 4 without having to pull any new cables.

7 valves have existing wiring identical to that depicted in Figure 2 for a non- .

locking valve. These valves have been determined in Calculation EC-VALV'-1043to be locking valves. Therefore, the circuitry could have been wired identical to.. that depicted in Figure 2 for a locking valve., This means that the 42F.contactlocated near the torque switch may be eliminated. This willprovide a spareconduc'tor that can be used to relocate the Torque/Limit Switches in a

manner.'dentical

to that depicted in Figure 4.

Rewiring ofExisting Interposing Relays:

3 valves require that the existing 42F contact remain in the circuit because itfunctions as a seal-in around a spring return hand switch. These 3 valves,however, have existing interposing relays. By rewiring these interposing relays ina manner identical to that depicted in Figure 3; the changes necessary to mitigatethe e6ects of the MOVhot short can be accomplished without adding anyadditional cables.

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Remaining 3 valves:.

HV-251-F004A, RHR Suppression Pool Suction Valve: For this valve, the 42Fcoritact in series with the torque switch'also function as a seal-in around the hand-switch. The hand-switch is a maintain contact switch that would not require a seal-in to assure complete stroking ofthe valve. With the contact in'its current

"configuration, it willprevent the valve from being reversed prior to completing afull stroke. Allof the F004 valves on Unit 2 are wired in this manner, while all ofthe valves on Unit 1 are wired without this feature.

HV-.151-F047B and HV-251-F047A, RHR Hx. Inlet Valves, are wired similarly tothe F004A valve described above.

For all of these valves, the non-reversible feature is not required. This has beendetermined by a review of the GE E11 and A4l drawings. Therefore, these'valvesmay also eliminate the 42F contact in series with the torque switch and may.berewired to relocate the torque and limit switches as depicted in Figure 4.

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II TABLE1"

UNIT 1 MOTOR OPERATED VALVES

.VALVENO. .-SYSTEM ';DISPOSITION -'

~ '»,DISPOSITION BASIS

HV-143-F023B

HV-144-F004

RX RECIRC

RWCU

Damage to Valve due toHot Shorts must beprevented.

Operator ActionRequired

See discussion in section 6.2.6,ofAppendix C

An Operator Action to open breaker1Y219-18 has been included on DrawingE490 and is 'contained in Off NormalProcedure ON-100-009.'his action willclose valve HV-144-F033. See discussionin section 6.2.7 of Appendix C.

HV-01222B ESW Damage to Valve due to See discussion in section 6.2.4 ofHot Shorts must be Appendix Cprevented.

HV-01224 B1 ESW„. Damage to Valve due toHot Shorts must beprevented.

'ee discussion in section 6.2.4 ofAppendix C

HV-15766

HV-15768

SUPP. POOLDRAIN

SUPP. POOLDRAIN


An Operator Action to close the 157025,valve is required. See discussion insection 6.2.5 of Appendix C.

Operator Action An Operator Action to close the 157025Required valve is required. See discussion in

section 6.2.5 of Appendix C.

&

HV-149-F007,

HV-149-.F008

'V-149-F010,

HV-149-F012

HV-149-F013

FV-149-F019

'RCIC

RCIC

RCIC

RCIC

RCIC

RCIC

No impact to Shutdown

No Impact to Shutdown




\


See discussion in section 6.2.2 ofAppendix C,

See discussion in section 6.2.2 ofAppendix C

See discussion in section 6.2.2 ofAppendix C,See discussion in section 6.2.2 ofAppendix C

See discussion in section 6.2.2 ofAppendix

C'ee

discussion in section 6.2.2 ofAppendix C

HV-149-F022

HV-149-F031

RCIC

RCIC

No Impact to Shutdown See discussion in section 6:2.2 ofAppendix C

No Impact to Shutdown See discussion in section 6.2.2 ofAppendix C

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VALVENO

HV-150-F045

HV-150-F046

'YSTEM

RCIC

RCIC

;: DISPOSITION



'. ".DISPOSITION BASIS

See discussiqn in section 6.2.2 ofAppendix C


HV-149-F059

HV-149-F060

RCIC,

RCIC

No Impact to Shutdown, See discussion in section 6.2.2 ofAppendix', C

No Impact to Shutdown See discussion in section 6.2.2 ofAppendix C

HV-149-F062

HV-149-F084

i HV-15012

RCIC

RCIC

RCIC




See discussion in section 6.2.2 ofApp'endix C


See discussion in section'6.2.2 ofAppendix C

HV-11210B "RHRSW 'Damage to Valve due to See discussion in section 6.2.4 ofHot Shorts must be . Appendix Cprevented.

'V-11215B

HV-151-F003B

HV-151-F004B

RHRSW

RHR

RHR


Damage to Valve due toHot Shorts must beprevented to preservethe RHR flow path.



See discussion in section,6.2.3.6 ofAppendix C.

See discussion in s'ection 6.2.3.6 ofAppendix C.

HV-151-F006A RHR No Impact to Shutdown See discussion in section 6.2.3.2 ofAppendix C

HV-151-F006C

HV-151-F006B

HV-151-F006 D

HV-151-F007B

RHR

RHR

RHR

RHR

No Impact to,Shutdown




See discussion in section 6.2.3.2 ofAppendix C




HV-151-F008 RHR No Impact to Shutdown See discussion in section 6.2.3.1 ofAppendix C

HV-151-F009 RHR No Impact to Shutdown See discussion in section 6.2.3.1 of'ppendix C

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VAI.VENO

HV-151-F015B

HV-151-F016 B

HV-151-F017 B

HV-151-F024 B

HV-151-F028B

HV-151-F047B

HV-151-F048B

SYSTEM

RHR

RHR

RHR

RHR

RHR

RHR

RHR

DISPOSlTION


Damage to Valve due toHot Shorts must beprevented to preservethe RHR flow,path.





Damage to Valve due toHot Shorts must beprevented to preventbypassing the RHR Hx.

';DISPOSITION BASIS

See discussion in section 6.2.3.6 ofAppendix C.

A modification to prevent damage to thisvalve is required. See discussion insection 6.2.3.5 of Appendix C.






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TABLE2

UNIT2 MOTOR OPERATED VALVES

VALVENO.

HV-243-F023A

HV-243-F023B

HV-244-F001

HV-01222A

HV-01224A1

HV-25766

HV-25768

HV-249-F007

HV-249-F008

HV-249-F010

FV-249-F012

HV-249-F013

:-SYSTEM

RX RECIRC

RX RECIRC

RWCU

ESW

ESW

SUPP. POOL„

DRAIN

SUPP. POOLDRAIN

RCIC

RCIC

RCIC

RCIC

RCIC

.DISPOSITION

'amageto Valve due toHot Shorts must beprevented.



Damage to Valve due toHot Shorts must be

. prevented.









. '.DISPOSITION BASIS



An Operator Action to open breaker2Y219-18 has been included on DrawingE-690 and is contained in Off NormalProcedure ON-'200-009. This action willclose valve HV-244-F033. See discussionin section 6.2.7.of Appendix C.



An Operator Action to close the 257025valve is required. See discussion insection 6.2.5 of Appendix C.

An Operator Action to close the 257025valve is required. See discussion insection 6.2.5 of Appendix C:






HV-249-F019

HV-249-F022

HV-249-F031

rEC-013-0859.Page J-,'L-

RCIC

RCIC

RCIC

No Impact to Shutdown,



See discussfon in section 6.2.2 ofAppendix C


See discussion in section 6.2.2 of

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VALVENO

HV-250-F045

HV-250-F046

HV-249-F059

HV-249-F060

HV-249-F062

HV-249-F084

HV-25012

HV-2121 0A

HV-21215A

HV-251-F003A

HV-251-F004A

'"'YSTEM

RCIC

RCIC

RCIC

RCIC

RCIC

RCIC

RCIC

RHRSW

RHRSW

~ RHR

RHR

'.;:.DISPOSITION




No Impact to. Shutdown







Damage to Valve due toHot Shorts must beprevented to preservethe RHR flow Path.

'::DISPOSITION BASIS

'ppendixC











See discussion in section 6.2.3S ofAppendix C.

HV-251-F006A RHR No Impact to Shutdown See discussion in section 6.2.3.2 ofAppendix C

HV-251-F006C

HV-251-F006B

HV-251-F006D

HV-251-F007A

HV-251-F008

RHR

RHR

RHR

RHR

RHR





, No Impact to Shutdown






HV-251-F009 RHR/

No Impact to Shutdown See discussion in section 6.2.3.1 of

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:~VALVENO. SYSTEM .: .:; '," "'DISPOSITION;::.::..'DISPOSITIOM BASIS

'ppendixC

HV-251-F015A

HV-251-F016A

HV-251-F017A'V-251-F024A

HV-251-F028A

HV-251-F047A

RHR

RHR

RHR

RHR

RHR

'HR

Damage to Valve due toHot Shorts must beprevented to'preservethe RHR flow

path.'amage

to Valve due toHot Shorts must beprevented to preservethe RHR flow path.

, „Damage to Valve due toHot Shorts must beprevented to preservethe RHR flow path.



, Damage to Valve due toHot Shoits must beprevented to preservethe RHR flow path.


A modification to prevent damage to thisvalve is required. See discussion insection 6.2.3.5 of Appendix C.

See discussion in section 6.2.6 ofAppendix C.

See discussion in section 6.2.3.3 of .Appendix C



HV-251-F048A " RHR Damage to Valve due toHot Shorts must beprevented to preventbypassing the RHR Hx.


EC-013-0859Page/~~'

Table 3- Appendix R- MOVHot Short Valves

v

Device 'MOV No. Systcm- Schcmatic-Drawing

Relays existin thc Motor

ControlCenter'pare-:"

-.

Coridiicto'rs'inthe existing

Field Cable to, ', Device'....,,.

;, Re'qiitre. Addition of

InterposingRelays

' Ma'niial,Opc'ratIon ofValve,UsingHaiidwhcxcl

.: =Possible...:

HV-EI I-IF003 B HV-151-F003B U-I RHR E-153 SH. 11 X

HV-'151-F015B . U-'I RHRHV-EI 1-1 F015BHV-EiI-IF016 B HV-151-F016B U-I RHR

HV-ElI-IF004B HV-151-F004B U-I RHR E-153 SH. 10

E-153 SH. 16

E-153 SH. 114

XX

HV-ElI-IF017B HV-151-F017B U-I,RHR E-'153 SH. 14 X

U-I RHRHV-El'I-IF048B HV-151-F048BHV-ElI-IF047B HV-151-F047B '-IRHR E-153 SH. 107

E-153 SH. 9 -XX

HV-I1210B'V-11215B

HV-11210BHV-11215B

U-I RHRSWU-I RHRSW

E-150 SH. 11

E-150 SH. 12- X

HV-B31-IF023B HV-143-F023B U-I RX RECIRC E-151 SH. 8 X N/A

HV-01222B HV41222B'HV-01224B I HV-01224B I

ESWESW

E-150 SH. 4

E-150 SH. 8 XX

HV-El I-2F003A HV-251-F003 A U-2 RHR E-153 SH. 56 XHV-EI I-2F004A HV-251-F004A U-2 RHRHV-ElI-2F015A HV-251-F015A U-2 RHR

E-153 SH. 55

E-153 SHv 61 XX

= EC-013-OS59

Page /~'y"ra

Device

HV-El1-2F016AHV-E1 1-2F017AHV-E11-2F047AHV-EI 1-2F048A

MOVNo.

HV-251-F01'V-251-F017A

HV-251-F047AHV-251-F048A

System

U-2 RHRU-2 RHRU-2 RHRU-2 RHR

SchematicDraiving

E-153 SH. 100

E-153 SH. 59

E-153 SH. 108

E-153 SH. 54

Relays existin the Motor

ControlCenter

SpareConductors in

the existingField Cable to

Dcvicc'-

. RequireAdditiotiofInterposing

Relays

XX

ManualOperation ofValve UsingHandwheel

. Possible

X

HV-21210AHV-21215A

HV-21210AHV-21215A

U-2 RHRSWU-2 RHRSW

E-150 SH. 23

E-150 SH. 22 X

HV-B31-2F023A HV-243-F023A U-2 RX RECIRC E-151 SH. 24 X N/A

HV-01222AHV-01224A1

HV41222AHV41224A1

ESWESW

E-150 SH. 32E-150 SH. 33 X

'n "X'n this column means that a spare conductor exists in the valve electric circuitry. A "Y"in this column means that the valve circuitry is wired for, anon-locking operator when, in fact, the operator is locking. Therefore, a spare contact exists in the circuitry that may be eliminated. This willfree up a

conductor for use in relocating the Torque/Limit Switches. A"Z" means the non-reversible feature on this valve can be removed.EC-013-0859

Page/+70

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TABLE4

RECOMMENDED SOLUTION FOR RE UIRED VALVES

'Device MOVNo. System SchematicDrawing

Possible Disposition

HV-EI I-IF003B HV-151-F003BHV-EII-IF004B HV-151-F004BHV-E11-IF015B HV-151-F015BHV-EI1-1 F016B HV-151-F016BHV-EI I-IF017B HV-151-F017BHV-EI 1-1 F047B HV-151-F047BHV-E11-1F048B HV-151-F04 8B

U-1 RHRU-1 RHRU-I RHRU-1 RHRU-I'RHRU-1 RHRU-I RHR

E-153 SH. 11

E-153 SH. 10

E-153 SH. 16

E-153 SH. 114

.E-153 SH. 14

E-153 SH. 107

E-153 SH..9

Relocate Tor ue/Limit Switches

Relocate Tor ue/Limit Ssvitches

Rewire Exist. Inte sin RelaysRelocate Tor ue/Limit SwitchesRelocate Tor ue/Limit SwitchesRelocate Tor ue/Limit SwitchesRelocate Tor ue/Limit Switches

HV-11210BHV-11210BHV-11215B HV-11215B

U-I RHRSWU-1 RHRSW

E-150 SH. 11

E-150 SH. 12

Relocate Tor ue/Limit SwitchesRelocate Tor ue/Limit Switches

HV-B31-IF023B HV-143-F023B U-I RX RECIRC E-'151 SH. 8 Relocate Tor ue/Limit Switches

0 HV41222B HV-01222BHV41224B I HVA1224BI

HV-E11-2F003A HV-251-F003 AHV-El1-2F004A HV-251-F004AHV-EI I-2F015A HV-251-F015AHV-E11-2F016A HV-151-F016A

ESWESW

U-2 RHRU-2 RHRU-2 RHRU-2 RHR

E-150 SH. 4

E-150 SH. 8

E-153 SH. 56E-153 SH. 55E-153 SH.

61'-153

SH. 100


Relocate Tor ue/Limit SwitchesRelocate Tor uc/Limit SwitchesRewire Exist. Inte osin RelaysRelocate Tor uc/Limit Switches

U-2 RHRHV-E1 I-2F017A ~ HV-251-F017AHV-E1 1-2F047A HV-251-F047A U-2 RHR

E-153 SH. 59E-153 SH. 108


HV-21210A " HV-21210A

HV-E11-2F048A HV-251-F048A U-2 RHR

U-2 RHRSW

E-153 SH. 54

E-150 SH. 23


Relocate Tor ue/Limit SwitchesHV-21215A HV-21215 A U-2 RHRSW E-150 SH. 22 Relocate Tor ue/Limit Switches

HV41222A HV-01222A ESW

HV-B31-2F023A HV-243-F023A U-2 RX RECIRC E-151 SH. 24

E-150 SH. 32


Relocate Tor uc/Limit SwitchesHVA1224AI HVA1224AI ESW E-150 SH. 33 Rewire Exist. Inte osin Relavs

The recommended disposition is to install i'nterposing relays. The disposition provided below isprovided as an option should insufficient space bc available to install thc relays. Ifthis disposition is used,

~ an Appendix R review must be performed as a part of the modification package preparation to assure that, thc change does not create a new Appendix R non-compliance in an area outside of the main Control

Room.

EC-013-0859

Page/M7/

L.C.

12 23TO FPC 20

22

19

49 40C)

MN: COND.

LRW.

L.C.

6A IA

KEEP FILL. pA 160A

RPV

I 60B 5pB 2IB 6P

ORIF IC17 VAL

28A-

SAMPLE

7A 5A

ECIR

LO 67

B

CONDXFR

ISB 17B + 4 28B

FROM 48FPC/

53A . 24

ULL 'FLPII TEST

34A, 3 I A

. LO7A

A =,C-671 ';

D B

+% 24

3IB j 34B

B LO7B

i 53B

34B

TORCIC RHR

CONDENSATEDEACTIVATED

'

34C 31CI

LO

+ 6AO

6B +%

~ 0

310 34OI

IL'0

LIJ

I-DO

TORCIC '

CONDENSATE~ DEACTIVATED

— REQUIRED VALVESCAN BE OPERATEO AT R.S.P

- VALVE ISOLATEOFROM C.R.'VALVE ISOLATEO FROM C.R.b CAN BE OPERATEO AT R.S.P.

Fl'GURE /AFLO&'ATH — RHR ALTERNATESHUTOONV COOLING

UNI'T Pl

p(- ~>Q -('>g.Q

'8<~ 277~

RHRUI...FLWPATH,SHD,CLG,P

A

e

0

wr ~

'L.C.

12 23TO, FPC 20

22

19

49 408

MN. COND.

LRW

L.C.

6A IA

KEEP FILL PA I 60A

RPV

160B 50B 218 6KEEP ILL

ORIFIC17 VAL

8A 4 4 7A 5

ECIR

A

LO 67

CONDXFR

158 178 88

FROM 48FPC

Q.XM

ULL FLOW TEST

34A .3 I A

LO'A

A C

671'

B

o tt 3IB, 34B

LO7B

53B

34B

TO .

RCIC RHRCONDENSATE z;DEACTIVATED

I-WI-o

34C 31CI

LO C

%% 6AoO

6B 4

0

310 . 34OI

LO

I-4J

I-O

TORCIC

~ CONDENSATE~+ DEACTIVATED

- REQUIRED VALVESCAN BE OPERATEO AT R.S.P.-

- VALVE ISOLATEOFROM C.R. I

- VALVE ISOLATEO FROM C.R.8 CAN BE OPERATEO AT R.S.P.

F2GURE /BFLOP PATH — RHR ALTERNATE SHUTDOWN'N COOLIN6.

UNIT f2

RHRU2, ,FLWPATH,SHD,CLG,P

If

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13-0859 .

page /+7/

0 ( pg

S —Transfer Switch at Remote Shutdown PanelHS-CR - Control Room Control SwitchHS-RSP - Remote Shutdown Panel Control SwitchNote: Scheme shown for manual control. at Remote Shutdown Panel

49ThermalOverhad

95ThermalOverloadBypass

49ThermalOverload

95ThermalOverhadBypass

ZSOpen when

Valve is100%

CLOSED

TSOpen on

HIGHClosingTorque

ZSOpen when

Valve is100%OPEN

ZSOpen when

Valve is100%

cLosED

TSOpen on

HIGHClosing

42FTorque

ZSOpen when

Valve is100%OPEN

HSS HSS HSS HSS HSS HSS HSS HSS

HSS

HS-RSPClose

HSS

i HS-CRi CloseControl Room

HSS

LHS-CROpen

HSS

HS-RSPOpen

HSS

HS-RSP.*:

Close :':

HSS

HS-CR LHS-CRClose ' Open

Control Room

HSS HSS

i

HS-RSPOpen-

42R 42F 42R 42F

42F 42R 42F 42R

~CLOSEValve Operator

WithLocking Worm Gear

OPEN~Fi ure2

~CLOSEValve Operator

WithoutLocking Worm Gear

OPEN~

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EC-013-0859page ~kg

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Note: Valve Operator with Locking Worm hownValve Operator without Locking Worm Gear ~ imilar

HSS

I

I

I,I

I

I

I

HSS HSS HSS

1I

I

I

I

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49ThermalOverload

II'SI OpenwhenI Valve isI 100%I GLosEDI

I


TSOpen on

HIGHClosing "Torque

I

I

ZSOpen when

Valve ls I100% IQPEN I

I

. HSS

LHS-RSPClose

HSS

i HS-CRi CloseControl Room

HSS

HS-CROpen

HSS

lHs-RsP

Open42FX 42RX

InterposingRelays

42R 42F

42FX 42RX 42F 42R

CLOSE OPEN CLOSE OPEN~

Valve Operator With Locking Worm Gear

Fi ure3

EC-01" 9page ~

Note: Valve Operator with Locking Worm GValve Operator without Locking Worm Gear I

ownmilar

49ThermalOverhad


I

HSSI

I

I

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I

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HSS.I

I

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rZS

+ Open whenI Valve isI 100%I CLOSEDL

TS-Open on

HIGHClosingTorque

42R

HSS HSS HSS

HS-RSP' HS-CR 'HS-CR

Close l Close l OpenControl Room

HSS HSS HSS

S-RSPOpen

I

ZSOpen when I

Valve is I

100% I

QPEN I

42F

42F 42R

~CLOSE, OPEN~Valve Operator With Locking Worm Gear

Fi ure4

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lt

t

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Al l, I

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