ML20195D514
| ML20195D514 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 10/26/1988 |
| From: | Holahan G Office of Nuclear Reactor Regulation |
| To: | ARKANSAS POWER & LIGHT CO. |
| Shared Package | |
| ML20195D522 | List: |
| References | |
| NUDOCS 8811070041 | |
| Download: ML20195D514 (11) | |
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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMIS$10N In the N tter of ARKANSAS POWER & LIGHT Docket No. 50-368 COMPANY (ArkansasNuclearOne Unit?)
EXEMPTION 1
Arkansas Power & Light Cenpany (apt.L or the licensee) is the holder of Facility Operating License No. NPF-6 which authorizes the operation of Arkansas Nuclear One, Unit t (the facility) at a steady state power level net in excess of 7815 negawatts therral. This license provides, anong other things, that the facility is subject to all rules, regulations, and Orders of the Nuclear "etulatory Conrission (the Comission or the staff) now or hereafter in tffect. The facility is a pressurized water reactor (FWR) located at the licenset's site in Pope County, Arkansas.
II The 10 CFR 50.48, "Fire Protection," and Appendix R to 10 CFR Part 50, "Fire Protection Progran for Nuclear Facilities Operating Prior to January 1, 1979" set forth certain fire protection features required to satisfy the General Cesign Criterion related to fire protectico (Criterion 3. Appendix A to 10 CFP Part 50).
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k Section III. G of Aprendix R requires fire protection for equipment impor-tant to post-fire shutdown. Such fire protection is achieved by various combinations of fire barriers, fire suppression systems, fire detectors, and separation of safety trains (I!!.G.7) or alternate post-fire shutdown equipment freeofthefirearea(III.G.3). The objective of this protection is to assure that one train of equipment needed for het shutdown would be undamaged by fire, and that systerrs needed fur cold shutdown could be repaired within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> (III.G.I).
Section !!I.0 of Appendix R requires that energency lighting units witi. at least an E-htt.r battery power supply be provided in all areas needed for cpera-tien cf safe shutdown equiprent and in access and egress routes thereto.
Section III.0 of Arterdix R requires that facilities have a reactor coolant purp oil collection systen if the containt,+nt is not inerted during I
norr.a1 operaticr. This systen r.ust be 50 designed, engineered, and installed that failure during norral or design basis accident conditions will not lead to fire, and that there is reaserable assurance that the system will withstand the Sefe Shutdown Eartheuake. Additionally the system rust drain to a vented t
closed centainer that can hold the entire lute oil system inventory, i
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Ey letter dated August 15, 1984, the licensee provided cetails of their fire protection y ogram and requested approval of a nurber of exemptions from the tectnical requirerents of' Sections III.G. !!I.J. and 111.0 of Appendix R to IO CFR Fart 50.
By letters dated August 30, 1985 and October 29, 1987 the licensee requested approval of a number of additional exenptions from Appendix A.
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3 Supplerental infonnation was provided by the licensee in letters dated October 20, 1986 and April 22 and June 24, 1987, and September 13, 1988. A description of the exemptions requested and a sumary of the Consnission's evaluation follow.
Exemption Requ_e_s gd Tne licensee requested exerption from Section I!!.G.2.b due to a lack of 20 feet of separation free of intervening corbustible raterials between the redundant diesel generator exhaust fan outlets (Fire Area B Fire Zone 2114-1).
The staff's principle concerns were that a pathway existed which could allow fire to spread and darrage the redundant systee,s, and that the lack of fixed suppression systens and fire detectors throughout this fire area could pernit a fire to spread and result in the loss of safe shutdown capability.
However, because of the light con.hustible loading in these fire zones, it is iot expected that a fire of significant duratier. or magnitude will occur.
Ttere are no intervening corbustibles between the redundant safe shutdown
!ystems.
If a fire were to occur in or near one of the exhaust fans, it would be expeted to develop slowly with initial low heat release and slow terperature rise. The lack of a roof over Fire Zone 2114-I would preclude any accumulatter.
of hot gases over this equipinent.
Further, in order for the fire to seriously affect the redundant equiprent, it would have to spread over and down into the room belcw, which is not considered credible. Additionally the licensee has cor'pleted the installation of 3-hour rated fire doors between redundant trains of
equipment. Therefore, the possibility of a single fire in one of these fire zones daraging redundant equiprent becores extrerely unlikely, despite the horizontal separation distance of less than 20 feet between redundant trains.
On this basis, the staff concludes that the licensee's alternative fire protection configuration provides an equivalent level of fire safety to that achieved by compliance with Section III.G.2.b.
The r,pecial circunstances of 10 CFR 50.12 apply in that application of the regulation in the particular circumtances is not necessary to achieve the underlying purpose of the rule.
In this case, the ligSt conbustible leading, the non-credible path necessary for the fire to spread to tre redundant safe shutdown equipoent, end the installation of 3-hour fire rated doors concitted to by the licensee, all provide assurance that the redundant tr61r.v.111 tt adequately protected. Thus the underlying purpose of the rule would tt satisfied without requiring spatial sep6 ration of the exhaust fan outlets.
F> eret ion _ f e, ques,ted The licensee requested exerption from Section !!!.G.3 due to a lack of a fixed fire suppression system in the control room and printer room (Fire Area 0, Zone 2199-G), which are roon.s for which an alternate shutdown capability has been provided.
The corbustible loading in these reors is roderate, consisting of paper, clothing, and electrical cable insulation.
If a fire were to occur, it is expected that it would develop at a slow to roderate rate.
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5 detectors are provided in the safety-related control cabinets and the rooms are continually occupied. The separation between adjacent control panels limits the spread of fire. The alares for the detectors annunciate in the control rocer..
If a fire occurs, it is expected to be promptly detected. The control roon operators will alert the plant fire brigade to extinguish the fire nanually if the operators have not. Separation of adjacent control panels.
smoke detectors, continual occupancy of the control roorrs, portable extinguishers, and alternate shutdown capability for this fire area all provide reascrable assurance that a fire ir. Fire Zone 2199-G will not prevent a safe plant shutdown. On this besis, the staff cencludes that the licensee's alter-r.atise fire protection configuration provides an equivalent level of fire safety to that achieved by corpliance with Section 111.G.3.
The special circunstances of 10 CFR 50.12 apply in that application of.the regulation in the particular circurstances in not necessary to achieve the ur.derlying purpose of the rule. The rule is eneant to ensure that a fire in the control roor er trinter roon would not prevent a safe plant shutdown. The exit,tirit fire protection features provide reasonable assurance that the ability to achieve safe shutdown of the plant is traintained. Thus the underlying purpose of the rule wculd be satisfied without requiring a fixed fire suppres-sien system.
Exerption_Re,ges,ted Thelicenseerequestede$erptionfromSection!!!.G.P.bduetotheleckof an autciratic fire suppression system in the upper and lower south piping renetraticr roots (Fire Area EE, Zor,e PCF4-DD and 2055-00). These roers
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contain cables, equiprent, and associated ncn-safety circuits of redundant trains which are separated by a horizontal distance of at least 20 feet free of intervening conbustible raterial or fire hazards and are protected by fire detection systems.
The staff's principle concern was that a lack of an automatic suppression system could perrit a fire to spread and result in the loss of safe shutdchn caratility, b'owever, because of the roderate conbustible leading in these fire zores erd the arrangec+nt of cat,les in trays a fire of significant magnitude is not expected to occur. Also because the cable trays are located at least 4 feet ateve the redurdant safe shutdctn related valves, the cables in them are not considered to be an intersening corrbustible. The redundant valves are greater than 20 feet apert, so it is very unlikely that they would all be daraged by a sircle fire.
If a fire were to occur it would be detected by the fire detectier system, which would anrunciate an alarm in the control room.
The fire trigadt; would arrive stcrtly and extinguish the fire, using existing fire fighting equirnert.
If fire derage occurred to the electrical circuits supplying the salve noter operators, the valves could still te crerated nanually locally. Also, only one of the redundant valves is needed for safe shutdown and is not required until at least li hours af ter a fire. On this basis the staff concludes that the licensee's alternative fire protection configuration provides an equivalent level of fire safety to that achieved by corrpliance with Section !!!.0,2.b.
The special circunstences of 10 CFR 50.12 apply in that application of the regulation in the particular circurstances is not necessary to achieve the ur+'erlying rurpose of the rule.
In this case the moderate fire leading,
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the spatial separation free of intervening corrbustibles between redundant safe shutdown related valves, the capability of the fire brigade to respond quickly I
once a fire is detected by the autcratic fire detection system all provide assurance that redundant safe shutdown cornponents will be adequately protected.
Thus the underlying purpose of the rule would be satisfied without requiring automatic suppression systeers in the upper and lower south piping penetration roers.
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Fyerrtion Reguested l
The licensee requested an e>enption fror. Section !!!.G.P.a due to a lack of a ccuplete 3-tcur fire-reted barrier between redundant level transmitters foritesafetygradecondensatestoragetank(CCST)(YarcArea).
Tht staff's principle concern was that a fire could result in darrage to redundant corporents or catles associated 6ith the (CST level indication.
Fevever, there are no significant unmitigated in-situ fire hazards which would represent a risk to these cenponer.ts.
In ettition the introduction of signif-l icant quantities of transient centustibles is precluded by the difficult access to the location of the conponents. Should a fire occur it would probably j
te of limited nagnitude, and the resulting smoke and hot gases would tend to bc
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dissipated in the open air, away from the subject coerponents. The physical configuratien of the areas where the QCST level indication corponents are located will provide sufficient protection to assure that at least one safe shutdown train will remain free of fire darrage until the fire brigade arrises to e>tinguish the fire, utilirirs existing fire fighting equipnent. On this l
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I basis the staff concludes that the licensee's alternate fire protection config-uration provides an equivalent level of fire safety to that achieved by i
corp 11ance with Section I!!.G 2.a.
The special circunstances of 10 CFR 50.12 apply in that application of the regulation in the particular circumstances is not necessary to achieve the underlying purpose of the rule.
In this case the absence of significant in-situ fire harards, and the physical locatien and arrangerent of the equirnent provide assurance that the redundant level indication equipnent would i
be adaeuately protected until the fire was brought under control by the fire l
brigade. Thus the underlying putpose of the rule would be satisfied without requiring a 3 tcur fire-rated barrier t.etwcen the redundant CCST level trans-nitters.
l E>errtiyi,fe, quested l
The licensec requested an e>erption froc. Section !!!.0 due to a lack of a reactor coolant punp oil collectico syster that is designed to withstand a safe i
i stutdown earthquake (SSE) air; aired to hold the oil fron: all reactor coolant pumps.(PCPs).
l The licensee stated in a letter dated August 15. 10F4 that the reactor coolant purp it,te oil systems are qualified to remain functional during and i
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after en SSE. Therefore the following guidance of Generic Letter 8610,
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"Irplenentation of Fire Frotection Requirernents," applies:
l Khere the RCF lobe oil systen is capable of withstanding the safe shutdown l
earthquete (SSE), the analysis should assure that only rander oil leaks frcc. the joints could occur during the lifetint of the plant. The oil collecticn syster, therefore, shculd be designed to safely channel the
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quantity of oil fron one purp to a vented closed cor.tainer. Under this set of circunstances, the oil collection system would not have to be seistically designed.
The existing oil collection system is designed to safely channel the quantity of oil fron one punp to a vented closed container, and so confortns with the ateve staff guidance. On this basis the staff concludes that the licensee's alternate design of the oil collecticn syster provides an equivalent level of fire safety to that achieved by corpliar.ce with Section !!!.0.
The srecial circur: stances of 10 CFP S0.17 apply in that application of the regulation in the particular circuristances is not necessary to achieve the urderlying purpose of the rule.
In this case the design of the reactor l
coolart purp lubricatirig systers ar4 the oil collection systers niets certain criteria previcusly deterriined by tbt staff to be acceptable for assurir.g j
attquate fire safety.
Thus the underlyir.g purpose of the rule would be sat-isfitd without requiring the oil collectici systen to be seisinically qualifitt I
and capable of holding the oil contained in all of the reactor coolant perps.
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.Eyy p,t,i e,n,,Pyo.u e s te d j
The licensee requested an e>crption fron Section 111.0 cue to a latt of f
E-tcur battery pckered er.ergency lighting units in the access paths to the intake structb... and diesel fuel storage vaults which are areas required to be tonned for safe shutdown. Because these locations are essentially
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identical tc locations involved in an exerption from Section Ill.J granted for i
l' nit 1, there is ne need for an exenption for Unit 2.
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l IV.
l Accordingly, tte Corrissien has deterriined that, pursuant to 10 CFR 50.1?.
this Exenption is authorized by law, will not present an undue risk to the
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public health and safety, and is consistent with the comen defense and security.
The Comission has further determined that special circumstances, as set forth in 10 CFR 50.12(a)(2)(ii), are present justifying the Exeinption, narely that e
the application of the regulation in the particular circumstances is not necessary to achieve the underlying purpose of the rule.
Specifics are discussed in each exception request, but in general the underlying purpose of the rule is to t
accomplish safe shutdown in the event of a single f
, and n intein the plant 3
in a safe condition. This is acconplished by assuring that sufficient undamaged r
equipnent is available to suppert safe shutdown, assurring a fire within the i
area of corcern.
In the areas for which an exeeption is being requested, passive as well as actise fire protection features assure that any single fire i
i vill not result in the loss of safe shutdcwn capability. These features include separation dister.ce, fire barriers, water spray systems to preclude i
prcragatitt, ard nanual actions. The fire protection features, in conjunction with low cenbustible loading and in seu cases physical location and configura-l l
tic.r. provide a high degree of assurance that a single fire will not result in l
loss of st-fire shutdown capability.
l Accordingly, the Corrissicn hereby grants the exenptions frorn the i
i requirenents of 10 CFR Part 50, Appendix R as described in Section 111 above.
Fursuant to 10 CFR 51.32, the Comission has detertnined that the granting of this Exerrption will have no significant inpact on the environrent (53 FR 7939E).
l The Safety Evaluation concurrently issued and related to this action anc f
l the above referenced sutrittals by the licensee are asailable for public l
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11 inspection at the Conmission's Public Document Room, 7120 L Street, N.V.,
Washington, D.C., and at the local public docutent room located at the Tomlinson Library, Arkansas Technical University Russellville, Arkansas 72801.
This Exception is effective upon issuancei, FOR THE NUCl, EAR REGULATORY COMMISSION 38 N
Gary}M.Hola.an,ActingDirector Divisien of Reactor Projects - !!!,
IV, Y and Special Projects Office of Nuclear Reactor Regulaticn Dated at Reciville, Maryland this 26thdey of 0ctober,1988 e
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