ML20023B857

Safety Evaluation Supporting Util Request for Exemption from Sections III.G.3 & Iii.L of 10CFR50 App R Re Alternate Safe Shutdown Capability

ML20023B857
Person / Time
Site:	FitzPatrick
Issue date:	04/26/1983
From:	Office of Nuclear Reactor Regulation
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Shared Package
ML20023B859	List: ML20023B857
References
NUDOCS 8305060557
Download: ML20023B857 (12)

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NUCLEAR HEGULATORY COMMISSION 5

E WASHINGTON, D C. 20555 k....,/SAFETYEVALUATIONBYTHEOFFICEOFNUCLEARREACTORREGULATI APPENDIX R TO 10 CFR PART 50, SECTIONS Ill.G.3 AND III.L POWER AUTHORITY OF THE STATE OF NEW YORK JAMES A FITZPATRICK NUCLEAR POWER PLANT DOCKET NO. 50-333 Introduction On February 17, 1981, the fire protection rule for nuclear power plants, 10 CFR 50.48 and Appendix R to 10 CFR Part 50, became effective.

This rule required all licensees of plants licensed prior to January 1,1979, to submit by March 19, 1981:

(1) plans and schedules for meeting the applicable requirements of Appendix R, (2) a design description of any modifications proposed to provide alternative safe shutdown capability pursuant to Section III.G.3 of Appendix R, and (3) exemption requests for which the tolling provision of Section 50.48(c)(6) was to be invoked.

Section III.G of Appendix R is a retrofit item to all pre-1979 plants regardless of previous safety evaluation positions and resolutions.

The criteria contained in Section III.L of Appendix R are used for thuse cases where licensees are incorporating alternate or dedicated shutdown capability.

Our previous fire protection Safety Evaluation Report (SER) dated August 1, 1979 concerning Branch Technical Position APCSB 9.5-1 indicated that in certain. plant areas redundant systems could be damaged by a single fire which would affect safe shutdown. We requested the Power Authority of the State of New York (licensee) to provide alternative shutdown capability for areas which could not be protected by fire barriers, fire detection and fire suppression systems. The SER specifically indicated that the relay room and the cable spreading room should be provided with alternative shutdown capability.

8305060557 830426 PDR ADOCK 05000333 PDR

2 By submittal dated July 13, 1982, the licensee provided the descriptions of the proposed modifications to the Fitzpatrick plant to meet the requirements of Appendix R to 10 CFR 50, Section III.G.

Tae proposed modifications will also resolve the open items from our previous SER dated August 1,1979.

Additional information and clarification was provided by submittals dated October,1980; March 19,1981; June 22,1981; February 26, 1982; and November 23, 1982; and was obtained during a meeting with the licensee on October 28, 1982.

Our evaluation of these modifications and actions follows.

SYSTEMS USED FOR POST-FIRE SAFE SHUTDOWN A.

Systems Required for Safe Shutdown Safe shutdown is initiated from the control room by a manual scram of the control rods.

Reactor scram can also be initiated manually by deenergizing the reactor protection system buses. Reactor coolant inventory can be raintained by either the reactor core isolation cooling system (RCIC), the high pressure coolant injection system (HPCI); or the low pressure coolant injection system (LPCI) or the core spray system (CS) in conjunction with the automatic depressurization system (ADS).

Reactor coolant system pressure is controlled by either the RCIC, the HPCI or ADS in conjunction with the residual heat removal system (RHR) in the steam condensing mode.

Decay heat removal is provided by either the RHR in the shutdown cooling mode; or the LPCI or the CS in conjunction with the RHR in the suppression pool cooling mode.

The support systems required for safe shutdown include the RHR service water system, the emergency service water system, the essential ventilation systems,'the emergency diesel generators and the essential electrical dis-tribution system, The above system will be monitored and controlled from the control room or the remote shutdown planel and local control stations.

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l B.

Areas Where Alternative Sife Shutdown is Proposed In our previous fire protection SER, we requested the licensee to provide

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alternative shutdown capability for areas which could not be protected by fire barriers, fire detectors and fire suppression system. By submittal dated July 13, 1982, the licensee committed to provide. alternative shut-j down capability in accordance with the requirements of Sections III.G.3 and I!!.L of Appendix R for the main control room, the relay room and the f

cable spreading room.

C.

Ramaining Plant Areas By submittat date,d July 13, 1982, the licensee indicated that all creas/ zones outside the reactor building will meet the requi rer:ent s of Section III.G.2 of. Appendix R.

For fire zones inside the reactor building, the licensee has requested a number of exenptions from Section III.G.2 of Appendix R.

Additionally, the licensee requested an exemption from Section III.G.2 of Appendix R for three y

phase AC and DC circuits, "to the extent that this would require further analysis and modifications to provide protection against the e xt remely unlikely occurrence of a two conductor (DC) or three

en uctor (three phase AC) power cable being severed by a fire

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and then reconnecting to cause matoperation of systems or tquipment."

For the case of the three phase circuits, the licensee indicated that two power circuits, one of which is energized and the other '

is non energized, would need to be damaged by the fire such that would be supplied to'the non energized circuit.

The licensee

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i indicated that for three phase circuits, this failure was unlikely.

l For the case of,the two-wire DC power circuits, the licensee

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indicated that the two power circuits, one of which is energized h

t and the other is non energized would need to be damaged by the i

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fire such that power woutd be supplied to the non-energized circuit.

1 Since the DC power systen is a non grounded systen, the short of the l

two circuits would have to occur prior to one of the circuits being l

shorted to ground.

Based on the unlikely occurrence of a three I

phase. circuit snort and a two-wire DC power circuit short before l

grounding, we conclude that the licensee's exemption request is a c c e p t e. b l e.

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D.

Atternative Sa1c Shutdown Systems The alternative shutdown capability wil L consist of a new auxiliary

~ hut do en pane L, local control and isclation switches, an'd alternate s

l control powe-feeders.

The new a uxi li a r y shutdown panel wilL be Located in the reactor bui t ding on etevation 300 feet.

The I

a t i e r r.a t i v e shutdown capability wilL utilize six safety relief valves and the Low' pressure coolant inj ection system (LPCI).

The safety relief valves wilL be controlled from the manual automatic depressurization system (ADS) panel Located in the reactor b'uilding.

The L?CI and the supporting RHR 5ervice water pump wilL be controlled from the new a uxilia ry shutdown panel.

The instrumentation for the

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alternative shutdown capability wi L L be, provided at the new auxiliary shutdown panel and a Local instrument rack.

The power supply for the alternative shutdown equipment witL bet upplied by the emergency

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S dieset generators.

The emergency diesel generators wilL be manually isolated f rom.the fire areas and locally started by breakers and controls located in the east electrical bay area, the emergency diesel generator switchgear room and the emergency diesel ~ generator room.

The design of the new auxiliary shutdown panel and the ADS panel wilL.

inctude control / isolation switches which when activated wilL electrically isolate the panel from the control room, cable spreadinh room and r'elay room and wilL transfer cont rol of t he shutdown equipment to the, panels.

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theauxilihry shutdown panel or the ADS panel wilL result A fire at in loss of control for only the equipment control' Led frbm the panet.

One train of systems needed for safe shutdown wilL be available and controllable from the main control room.

EVALUATION A.

Performance Goals For post-fire shutdown, the performance goals o f the alternat'ive saf e shutdown capability wilL be met utilizing six safet,y-relief. valves and the low pressure coolant injection system (LPCI).

Reactivity control wilL be provided by a manual scram of the control rods from the control room.

Six safety relief valves wilL Ee manually controlled to reduce reactor coolant system pressure.

After depressurization, the LPCI wilL provide reactor inventory makeup.

The LPCI wilL be 1

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used to establish a cooling path by allowing the reactor vessel water Levet tn. rise until water flows through the safety rel'ief lines into the suppression pool.

This cooling path provides reactor inventory control, suppression pool cooling and initial decay heat removal.

Extended decay heat remova L wilL be accomplished by the residual heat removat system (RHR) in the shutdown cooling mpde.

The RHR wilL require additional perscnne L to manually line up the system.

The LPCI is capable of providing sufficient cooling until the RHR system is initiated.

Process monitoring fo'r saf e shutdown wilL be provided by the instrumentation at the auxiliary shutdown panet and local instrument rack.

The folLowing instrumentation vill be available,at these panels:

reactor water level, reactor p'ressure, suppression pool temperature, suppression pool level, drywelL temperature, injection flowrate, LPCI pump discharge pressure and RHR service water flow rate.

The support systems available include the RHR service water systen, the emergency diesel generators and the essential electrical distribution system.

9.

72-Hour Requirement The alternative shutdown systems have the capability of achieving l

cold shutdown within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

The alternative shutdown systems can accomplish cold shutdown using only onsite power sources.

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The Licensee has requested an exemption from Sections III.L.4 and III.L.5 of Ap'pendix R,

"to the extent that if offsite power is lost, it must be restored within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />."

The Licensee jus,tified its exemption request' by indicating that the alterr.ative shutdown systems are power from onsite power sources,that the onsite power source:

(emergency diesel generators) have a 7-day fuel supply and that additional fuel is available from offsite locations.

Secticn III.L.3 of Appendix R states that the alternative shutdown

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capability shalL ace'ommodate post-fire conditions where offsite i s available and wher e of f site power is not available for 72 power hours.

For conditions where the cold shutdown equipment is not availabLe because of fire damage, Sections III.L.4 and III.L.S of Appendix R provide additional guidance.

For these conditions, the hot shutdown equipment and subsequent cold shutdown equipment used prior to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> after the f i r e*,

shalL be provided with an independent onsite power system, if the equipment wilL not be capable of being powered by both cnsite and offsite. power systems.

Additionally, cold shutdown equipment used after 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> may be powered by offsit'e power only.

We conclude that the Licensee's alternative shutdown capability meets these sections of Appendix R.

Additionally, the staff concludes that Appendix R does not require offsite power to be restored within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

Thus, the Licensee's exemption request is -

not needed.

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C.

Repairs The' design of the alternative shutdown system does not utilize repairs to achieve safe shutdown.

The Licensee has requested an exemption from Sections III.G.1.a, III.G.2, III.G.3 a n d III.L of Appendix R,

"to the extent that repairs are censidered to include Low voltage fuse putling, lifting of Leads and cabte cutting."

This exemption request was not utilized f or the otternative shutdown capability.

The Licensee justified the exemption

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r e'q u e s t by indicatin's that the procedures would identify the necessary cctions, the actions can be accomplished before unr'ecoverable plant conditions exist and the electrical connections a.e of low voltage.

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The Licensee's exemption request did not identify the fire areas for which this'exenption applied.

Our review of the Licensee's submittal identified two areas for which this exemption applied:

Fire Area CT-3 Cable Tunnel and Fire Area CT-4 Cable Tunnel.

For fire area CT-3, an RCIC Logic control power fuse must be removed to prevent spurious signals from affecting the use of RCIC.

For fire area CT-4, an HPCI Logic control must be removed to' prevent spurious signals from affecting the use of HPCI.

In each case the repair is limited to the removal-of a r. ingle fuse located in a panel in the relay room.

Other than a few manual -

operations, safe shutdown would be achievid from the control room x

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using equipment separate from the fire areas.

Based on the Licensee's commitment to provide procedures outlin,ing these repairs and the Licensee's statement that the repairs can be accomplished before an unrecoverable plant condition exists, we conclude that the Licensee's exemption request i s ia cceptable f o r fire areas CT-3 and CT-4.

D.

Associated Circuits The Licensee provided the results of their associated circuits review for the control room, t he ' cable spreading room'and the relay rgos.

The results identified the associated circuits of concern in these

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areas and the proposed methods for protecting the safe shutdown capability from fire-induced failures of these circuits.

The pro-posed methods for protecting the safe shutdown capability are consistent with the guidelines provided by us.

I 1.

Powe'r Source Case - The Licensee's analysis concluded that

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l alL power circuits w hi c h share a common pcwer bus with the-power circuits of the alternative shutdown equipment are provided with coordinated breakers or fuses.

2.

Spurious Signal Case - The Licensee's analysis identified a number of circuits whose fire-induced failures may adversely affect the safe shutdcwn capability.

The Licensee has proposed methods for protecting the safe

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shutdown capability consistent with the severity of the prcblem.

As part of the c o r.t r o l room evacuation proce-dures in the event of a fire in_the control room, cable spreading roon or relay room, an operator wilL canuaLLy isolate the essential electrical distribution

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system and the diesel generator from the fire area.

The isolation switches witL protect the e l e c t r i c a'l di,stribution l

l system and the diesel generator from spurious signals resulting from the fire.

The procedures, alsc, indicate I

that an operator wilL isolate the " control rod drive air header" air supply to the scram valves, thereby pro-viding protection against spurious control rod actuations.

Additionally, the alternative shutdown capability provides a number of local isolation / cont rol switches and local valve position indications.

The local isolation / control s w i t' c h e s are used to isolate al,ternative shutdown equipment from spurious c on t r o l-s i gn a l s resulting from.the fire and are used to transfer control of the shutdown 2quipment-to a local station.

The l o c'a l valve positior indications are j

used to yerify proper valve alignment and to identify l

j valves that require manual operation to overcome spurious signals resulting from the fire.

F u r't h e r, for prevention l

of a possible fire induced LOCA, the power for one of the i

redundant electrically controlled valves at the high/ Low pressure interface of the reactor coolant loop snd PHR pump suction Line, wilL be disconnected prior to raising-the pressure of the reactor coolant.

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Common" Enclosure Case - The Licensee's analysis identified no instances where associat ed circuits share a common enclosure with alternative shutdown circuits and are not electrically protected by circuit breakers, fhses.o~r similar devices.

E.

Safe Shutdown Procedures and Manpower The licentee has implemented procedures for the alternate shutdown capability using presently installed equipment.

These.,

procedures wilL be rev'ised as the new alternative shutdown ecuipment is availabLe. -The manpower necessary for safe shut-down using the alternative shutdown capability wilL be avail-cble.

No fire brigade members are included in the shutdown menpower requirements.

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The Licensee will submit Technical Specifications for the atte n.*tive shutdown equipment upon completion of the modi-fications.

< CONCLUSION Based on our review, we conclude th'at the licensee's request for exemption from Section III.G.2 of Appendix R concerning three Phase Ac and DC circuits is acceptable.

The licensee's request

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12 for exenotion from Sections III.G.1.a, III.G.2, III.G.3, and III.L of the Appendix R concerning the putLing of low voltage fuses is acceptable for fire areas CT-3 and CT-4 only.

Th'e Licensee's request for exemption from Section III.L.4 and III.L.5 concerning restoring offsite power within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is not needed.

Additionally we conclude that the performance goals for accomplishing safe shut-down in the event of a fire, i.e.,

reactivity control, inventory control, decay heat removal, pressure contro't, process ronitoring and support functions are met by the pr'oposed at,ternative shutdown capability.

Therefore, we conclude that the Lice 6see's alternative s.

shutdown capability for the control room, the cable spreading room and the relay room complies with the requirements of Section III.G.3 and'III.L of Appendix R.

APR E 6123 Dated:

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Principal Contributor:

N. Fioravante

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