ML20147G011
| ML20147G011 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 02/25/1988 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20147F976 | List: |
| References | |
| GL-86-10, NUDOCS 8803080107 | |
| Download: ML20147G011 (36) | |
Text
_.
[
4,$
3 UNITED STATES fL NUCLEAR REGULATORY COMMISSION j
j WASHINGTO N, D. C. 20655 e
ENCLOSURE _ 2 SAFETY EVALUATICN BY THE OFFICE OF NUCLEAR REACTOR REGULATION
-""' hllAT1W TL7FFlhblY k tithPTith5'RIDUE51ED FOR V I NDl hlh' E L E CTR I C7hD' PDRER'tDNPART ' " "
~ " ' "3bRRT PDRtR' STAl ION UNIT 5 1 ANYY" 00CVsET ND3'.'ED1280 AND 50-281
1.0 INTRODUCTION
By letter dated July 6, 1984, the Virginia Electric and Power Company (the licensee) sotmitted a report describing its cenpliance with Appendix R to 10 CFR 50. The submittal requested exemptions from Sections III.G, III.J and III.L of Agercix R to 10 CFR 50. Additicnal information was submitted by letters dated November 3C, 1984, April 10, 1986, September 30, 1986 and October if, 1907. The exemption requests identified in the submittels are the subject of this evaluation.
Section III.G.1 of Appendix R requires fire protection features to be previded for structures, systems, and components important to safe shutdewn and capable of limiting fire damage so that:
a.
One train of systems necessary to achieve and raintain hot shutdown ccnditions frcm either the control room or en+rgency control statien(s) is free of fire danage; and b.
Systems necessary to achieve and maintain cold shutdown fron either the control recm or emergency control station (s) can be repaired within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
Sectier III.G.2 of Appendix R, except as provided for in Paragraph III.G.3, requires that one train of cables and equipment, including associated nonsafety 1
circuits that could prevent operation or cause maleperation due to hot shcrts, open circuits, or shorts to ground, necessary to achieve and maintair safe shutdown be raintained free of fire danage by one of the following means:
a.
Separation of cables and equiprent and associated nonsafety circuits of I
redundart trains by a fire barrier having a 3-hour rating.
Structural steel forming a part of or supporting such fire barriers shall be protected i
to provide fire resistance equivalent to that required of the barrier.
b.
Separation of cables and equipr+nt and associated nonsafety circuits of j
redundant trains by a horizontal distance of more than 20 feet with rc intervening conbust.ibles or fire hazards.
In addition, fire detectors ard an autcratic fire suppression system shall be installed in the fire area.
8803080107 G80225 PDR ADOCK 05000280 p.
PDR 1
c.
Enclosure of cables and equipment and associated nonsafety circuits of one redundant train in a fire barrier having a 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> rating.
In addition, fire detectors and an automatic fire suppression system shall be installed in the fire area.
If the above conditions are not met, or where redundant trains of systems required for hot shutdown may be subject to damage from fire suppression activ-ities or from the rupture or inadvertent operation of fire suppression systems,Section III.G.3 requires that there be alternative or dedicated shutdown capability independent of cables, systems, or components in the fire area of concern.
It also requires that fire detection and a fixed suppression system he installed in the fire area, zone, or room of concern.
Because it is not possible to predict the specific conditions under which fires may occur and propagate, design basis protective features rather than the design basis fire are specified in the rule.
Plant-specific features may require pro-tection different from the measures specified in Section III.G.
In such a case, the licensee must demonstrate, by means of a detailed fire hazards analysis, that existing protection or existing protection in conjunction with proposed modifications will provide a level of safety equivalent to the technical requirements of Section III.G of Appendix R.
In sumary,Section III.G is related to fire protection features for ensuring that are train of systems and associated circuits necessary to achieve and maintain safe shutdown are free of fire damage.
Either fire protection con-figurations must meet the specific requirements of Section III.G or an alterr.ative fire protection configuration must be justified by a fire hazards analysis.
Generally, the staff will accept an alternative fire protection configuration if:
The alternative ensures that one train of equipment necessary to achieve hot shutdown from either the control room or emergency control station (s) is free of fire damage.
The alternative ensures that fire damage to at least one train of equipment necessary to achieve cold shutdown is limited so that it can be repaired within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> (minor repairs using components stored on the site).
Fire-retardant coatings are not used as fire barriers.
Modifications required to meet Section III.G would not enhance fire pro-tection safety levels above that provided by either existing or proposed alternatives.
Modifications required to meet Section III.G would be detrimental to overall facility safety.
s 2
2.0 AUXILIARY, FUEL, AND DECONTAMlhATION BUILDINGS (FIRE AREA 17) 2.1 Qeggti,on_ Requested An exerrption was requested from the requirerer.ts of Section III.G.3 to the extent that it requires fire detecticn and fixed autocatic suppression systems be provided tbrcughout the fire area, room, or zone for which an alternate shut-down capability has been provided.
7.? Discussion The licensee has stated in exemption request 1 that Fire Area 17 does not reet the requirenents of Section III.G.3 because fire detection and fixed automatic suppression systems are not provided throughout the fire area.
Fire Area 17 includes Fire Zones 17-la and 17-Ea and consists of the auxiliary, fuel, and decontamination buildings. The buildings are located-side-by side in a north / south orientaticn, with the auxiliary building to the south, the decon-tamination building to the north, and the fuel building in the center. This fire area contains the six charging pumps, the component ccoling water (CCW) purps, the charging purp-cooling water pumps ard associated cabling ard valves fer all of the purps.
Fire Area 17 is beurded to the south by the service building and each units' cable vault / tunnel (Fire Areas 1 ard ?), to the north by the plant exterior, to the east by the primary containnent and the cable vault / tunnel for Unit 2 (Fire Areas 16 and 2, respectively), and to the west by the primary centainnent ard the cable vault / tunnel for Unit 1 (Fire Areas 15 and 1, respectively). All barriers of adjacent fire areas are of 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> rated reinforced concrete con-struction, and electrical ard piping penetrations are sealed with 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire rated silicone fear, except for penetrations to the contairment.
The auxiliary building is a four-story structure consisting of elevations 2 feet, O inch; 13 feet, 6 inches; 27 feet, 6 inches; and 45 feet, 10 inches.
The CCW purps, charging purrps, and charging purp-cooling water pumps are located on the 2-foot, 0 inch elevation.
The CCW purps are located in the main open f1cer area of this elevation.
Each charging purp is located in a separate cubicle accessed from the 13 foot, 0 irch elevation.
Charging pump-ccoling water purps (two each for Units 1 and 2) are located outside the charging pwp cubicles.
The fuel building section of Fire Area 17 is a two-story structure. The decen-taminaticn building is a three-story structure, consisting ~of the 6 foot, 10 inch; 22 foot.,O inch; and 47 foot, 4 inch elevaticns.
An automatic fire detection system, which annunciates in the control rocm, is provided in Fire Area 17. Smoke detection is prcvided on each elevation of the auxiliary building, but it does not reet the criteria of full area coverage.
Cetectors are installed in all locations with significant an:ounts of ccmbustibles and near safe shutdown components.
~
3
Each charging pump cubicle has one ceiling-mounted and one duct-mounted smoke detector.
Two cei. ling-mounted detectors are installed above each unit's charging pump-cccling water pumps, which also alarm in the control room.
The fuel building is provided with ceiling-mounted smoke detectors while the decontamination building is provided with duct-mounted smoke detectors.
Fortable tytinguishers and hose stations are provided throughout Fire Area 17 for manual fite fighting purposes.
2.2.1 Charging Pump System Configuration and Separation The 2 foot, O inch and 13 foot, 0-inch elevaticns of Fire Area 17 are subdivided intc Fire Zones 17-la and 17-2a. Fire Zones 17-lb ard 17-2b are similarly arranged on the 13 foot, O inch elevation.
The Unit 1 charging pump components are located within Fire Zones 17-la and 17-lb and the Unit 2 charging pump components are located within Fire Zeres 17-2a and 17-2b. Yhere there is less than 20 feet of horizontal separation between the components, an 18 inch-thick reinforced concrete wall extending from the f1cor to the ceiling on both elevations has been erected.
The Unit 1 charging purps are located back-to-back against the Unit 2 charging pumps on the 2 foot, O inch elevation.
Each charging pump is enclosed in a cubical, with 18 inch-thick concrete walls that extend up to the ? foot, 0 inch elevatien ceiling.
The cubical walls extend up to the ceiling cf the 13 foot, O inch elevation on three sides.
The cubicles are open on the 13 foot, O inch elevatien side facing the respective unit.
Units 1 and 2 charging pump suction valves are located in separate charging pump cubicles separated by a heavy cercrete barrier wall.
The charging pw p power 'eeds for Units 1 and 2 exit their respective cubicles on the the 13 foot, O irch elevatien and are routed to their respective cable vaults / tunnels.
The minimum separation for Units 1 and 2 charging pump cables is nore than 40 feet.
Intervenirg cen.bustibles in the form of cable trays that run perpendicular to the charging pu p pcwer feeds are fire stepped approximately 20 feet frcm the intersection.
Therefore, a minimum of 20 feet of separatien withcut intervening ccabustibles exists between Units 1 ar.d 2 charging pump power feeds.
j l
2.2.2 Component Cooling Water System The CCW pumps are located side-by-side without 20 feet of separation.
The licensee stated that the pumps are needed only for cold shutdown. A repair procedure exists to facilitate the replacement of two CCW pwp motors arid asso-ciated cables in case of a fire in this area. Two spare motors and associated cables are maintained on-site for this repair.
2.3 E_ valuation The lack of "area-wide" fire detection and suppression is a conditien encom-passed by the revised interpretations of Appendix R contained in Generic Letter (GL) 86-10. According to these interpretations, no exemption for this 4
ccndition is recessary.
Fewever, the staff ccnsiders the evaluaticn and justi-i fication fcr the exemption subritted by the licensee as constituting the fire hazards aralysis required by the GL.
The staff's principal concern was that because of the absence of area-wide auto-matic suppression and detection systems, a fire of significant magnitude cculd deveicp and damage all CCW pumps, charging pumps, and/or associated cabling ard valves.
However, the combustible icading in Fire Area 1" is 1cw. An equivalent fire severity based on the ASTM E-119 time-temperature curve is less than 10 minutes for elevation 2 feet, O inch and less than 25 minutes on elevation 13 feet.
O inch. The conbustibles consist primerily of cable insulation and lube oil.
The six charging purps are separated b3 heavy concrete walls that have an inherent fire rating that exceeds 3 huurs.
The power feeds for the charging purps are separated by a minimum of 20 feet of horizontal separation. The fire steps installed in cable trays effectively reduce the pctential of fire spread along trays.
In addition, smoke detectors are provided ever each charging punp-cooling water pumps and within the charging pump cubicles. Smoke detectcrs are 1ccated near the cable trays at elevations 13 feet, O inch and 27 feet, 6 inches. Cetectors are also located near the intervening conbustibles between the charging pump pcher feeds.
Because of the presence of the detectors, a fire in the charging pump-cccling water purp area or a charging pump cubicle should be detected in its incipient stage. The detectors annunciate in the main control room and the fire brigade wculd be dispatched to extinguish the fire marually using hcsc lines or portable extinguisters provided.
It is concluded, therefore, that the installation of area-wide autcmatic fire suppression and detection systems would not significantly increase the level cf fire protection for Fire Area 17, 2.4 Conclusion l
Based on the above evaluation, the staff concludes that the licensee's analyses and justification for the absence of area-wide fire detection and suppression in Fire Area 17 are in confornence with the guidance issued in GL 66-10 and arc, therefore, acceptable.
l i
E
j 3.0 CONTAIhMENT INCORE INSTRUMENT TUhhELS (FIRE AREAS 15 AND 16) 3.1 Exerrpt ion,,Re,qu,e,s,ted An exemption was requested from the requirements of Section III.G.2.d to the extent that it requires redundant cables and equipment tc be separated by at least 20 feet with no intervening con,bustibles.
3.2 D_i,scussion The licensee has stated in exenptfor: request 2 that Fire Areas 15 ar.d 16 do not meet the rec,uirerents of Section III.G.2.d because less than 2C feet of separa-tion exists between redundant excore neutron flux detector cables.
Fire Areas 15 ard 16 are the primary containtreents for Units ' and ?, respec-tively.
Each area is a n.ulti-level structure with flocr elevatiens from
(-) 27 feet, 7 inches to 47 feet, 4 inches.
The incere instrurrentation canal is 1ccated below elevation (-) 13 feet, 0 inch.
The east, west, and north walls of each canal are 3 foot-thick reinforced concrete.
The circular wall to the south of each canal is constructed of 4 feet, 6 inches reinforced concrete.
The ceiling and floor of each canal are 2 foot-thick reinforced concrete.
Access to each canal is through a norno11y locked steel batch located at eleva-tien (-) 13 feet, O inch.
There is a 20 foot vertical steel ladder within each hatchway that provides access to the canal floor.
The northern end of each carai centains no exposed combustibles. All cables ir the canal are enclosed in rigid steel concuit. A surrp purp is located in ore corner of the canal.
The irecre instrunent tunnel for each unit contains cables for four channels of scurce range neutron flux indicatien.
Two of the channels were originally pro-vided as part of the nuclear instrunentation system and two channels were added in 1984-PE.
One of the new chanr.els for each unit is used tc provide neutren flux indication at the remote rtonitoring panel in the cable sareading room.
The other three channels provide neutron flux it;uicaticn in t,e control roem.
Separation exists between the two new channels of neutron flux indication.
The sane separation exists between one of the new channels for each unit and the existing scurce range neutron flux cables, t
The redundant charnels for the rew excore neutron flux detectors are routed in rigid steel conduit and are separated by 10 feet horizontally with no intervening corrbustibles in the canal.
Upen exiting the carals, the redundant trains run in opposite directions until a minitrum of 20 feet of separation free of inter-vening corrbustibles (xists between the trains.
6
Near and within the carals, the fixec combustible loading is minimal.
The potential fcr transient con.bustibles is limited since the access hatch is normally locked and access is controlled.
3.3 Evaluation Fire Areas 15 and 16 at the incere instronent tunnels do not comply with the technical requirenents of Section III.G.E.d of Appendix R because redundant cables ard equipment, specifically excore neutron flux detector cables, are not separated by 20 feet horizcr.tal distance with no 'ntervening conbustibles.
The ccabustible leading near the canals is minimal.
The canals contain no fixed combustibles. The potertial for transient conbustibles tc be intreduced ard stored in the canals is icw.
A rafor factor that reduces the potential fcr danage to reduedant source range neutren flux cables is that they are ccntained in rigid steel ccnduit.
The IC-fcot separation between redundant cables, the minimal ccn.bustible loading, and the installation of cables in rigid conduit provide sufficier.t passive pro-tection to ensure that ore divisien cf source range neutron flux cables would renain free of fire damage.
With the fire protection features as described above, reasorable assurance exists that a fire in the containment incere instrument tunnels (Fire Areas 15 and 16) will net prevent the plant from' safely shutting down due to loss of redundant exccre neutrcn flux detector cables.
3.a cerclusion Based on the above evaluaticn, the staff concludes that the existing fire pro-tection features provide a level of fire safety equivalent to the technical requirements of Section III.G.?.d of Appendix R.
Therefore, the exemption request from the requirement for 20 foot separat'cn between redundant exccre neutron flux detector cables shculd be granted.
7
l 4.0 MAIN STEAM VALVE H0tJSES (FIRE AREAS 19 AND 20) 4.1 Exemptio,n, Re, quested An exemption was requested from the requirements of Section III.G.3 to the extent that it requires autcmatic fire suppressicn systems thrcughcut each of the idertified fire areas.
4.2 Discussion The licensee has stated in exemption request 4 that Fire Areas 19 and 20 do not teet the requirements of Section III.G.3 because autcmatic fire suppression systems are not installed throughout each area.
F',re Areas 19 and 20 are the main steam valve hcuses for (Jnits 1 and 2, respec-tively. The areas contain the turbine-driven auxiliary feedwater (AFW) pump, two motcr-driven AFV pumps, the stean generator power-operated relief valves (PCRVs), the turbine-driver. AFW steam supply valves ard steam generator pressure indication. The steam supply valves for the turbine-driven AFW pump fail open and the FORVs fail c1csed.
Each fire area is. located in a separate structure south of and adjacent to the containment building (Fire Areas 15 ar.d 16) and west of and adjacent to the cable vaults / tunnels (Fire Areas 1 ar.d 2).
Fire Areas 19 and 20 are multi-level structures consisting of the 11 feet, 6 inch; 26 foot, 6 inch; 38 foot, 6 inch; 46 foot, 5 inch; and 57 foot, O inch elevations.
The fixed combustible leading in the areas is icw, consisting primarily cf cable insulation, grease and lubricating oil.
Ionization sacke detectors are provided in each of the fire areas at the upper elevation. The detectors alarm in the control room.
In addition, portable fire extinguishers and plant exterior hose stations are available for manual fire fighting.
A fire in the main steam valve houses could darage all three AFW pumps and the steam supply valve to the turbine-driven AFW pump.
Cross-connects located in the cpposite units' main stean valve house enable the opposite unit to supply auxiliary feedwater to both units. Loss of power to the steat generator PCRVs l
requires an alternate rethed of reroving decay heat.
The ccde safety valves will maintain the plant in hot standby until a manual valve lineup can be per-formed to release steam to atmosphere via the auxiliary steam system in the j
turbine buildirg.
Stean. generator pressure can be nonitored at the remote monitoring panel in the cable spreading recm.
l 8
y 4.3 Evaluation The lack of area-wide autcmatic fire suppressicn is a condition enccmpasscd by the revised interpretations of Appendix R contained in GL 86-10. Accordirg to these interpretaticns, no exemption for this condition is necessary. Mcwcycr.
the staff ccr.siders the evaluation and justificaticn for the exempticr. submitted by the licensee as constitutirg the fire hazards analyses required by the GL.
The staff's prircipal concern was that because of the absence of area-wide auto-matic fire suppression systems, a fire of significant magnitude could develop.
Fcketer, the corbustible leading in the areas is icw, consisting primarily of cable insulation, lubricating oil, ar.d grease.
If a fire were to occur, it is expected thet it wculd develcp sicwly with initial icw heat release and slew rise in recm temperature.
Icrization smoke detectors are provided in each of the areas at the upper eleva-tion. The alarns for the detectcrs are annunciated in the main control rocm.
The fire brigade would be dispatched to extinguish the fire manually, using the hcse lines or portable extinguishers provided.
With the 1cw combustible icading, fire detection capability, availability of roter-cperated cross-connect valves, availability of the auxiliary steam system, the rcacte rcnitoring panel, and the ability of the plant fire brigade to extinguish the fire prenptly so that a ranual valse lineup can be perforred, it is cercluded that the insta11aticn of an area-wide autcratic fire suppression system wculd rot significantly increase the level of fire protection for these areas.
d.d Cerclusion, Based on the above evaluation, the staff concludes that the licensee's analysis ard justification for the absence of area-wide fire suppression in the subject areas art in ccnformance with the guidance issued in GL 66-10 and are, there-fore, acceptable, 9
5.0 4-20 MA SIGNALS IN TVISTED PAIR INSTRUMENT CABLE 125-VDC CIRCUITS IN RIGID HETAL CONDUIT 5.1 Exemption, Re, ques,ted Exemptions were requested from the specific requirements of Section III.G.? to the extent that it requires the protection of low current instrunent circuits and 125-Vdc circuits that could prevent operation or cause maicperation due to hot shorts.
5.2 Discussion The licensee has requested, 'sn exenption requests 19 and 20, exemption from Appendix R fer 4-20 nA signals carried by instrunent cables, which are routed in raceway with other instrurent cables, and for 125-Vdc circuits serving high/
low pressure interfaces that are routed in dedicatea rigid steel conduits.
Areas in which one or more of the circuits are installed are the cable vaults and tunnels, main control reom, containrents, energency switchgear rooms, and main steam valve houses.
The licensee states that the condition of all four conductors of two adfacent low current leve' instrunent circuits, which are routed in raceway with uther instrunent cables fusing tcgether in the correct polarity with Icw inpedance, 's not credible.
In addition, a direct short (positive and negative conducterr contact each cther) or shcrt-to-grcund will cause a zero signal output.
The 125-Vdc circuits that are routed within a cable tray and provide motive pcwer to high/icw pressure beundaries that are susceptible to hot shorts must be protected in accordance with Section III.G.2 of Appendix R.
The licensee has cere:itted to route the circuits in dedicated steel conduit.
In addition, there are procedures that require the circuits to be deenergized in the event cf a fire.
The licensee has committed to provide a new isolaticn switch in the en.ergency switchgear room to ensure that the circuits can be deenergized from either the existing switch in the control rocm or from the energency switchgear rooms.
5.3 Evaluation Sections III.G.? and III.L.7 of Appendix R define circuit failure nodes as het shorts, open circuits, and shorts to ground.
For consideration of spuricus actuations, all possible functional failure modes must be evaluated; e.g., the component ceuld be energized or deenergized by one or more of the above failure modes.
Guid3rce concerning which failure mode must be considered in identifying cir-cuits associated by spurious actuation is provided in GL 86-10 dated April 24, 1986. GL 86-10 states that for ungrounded de circuits, if it can be shown that only twc shcrts of the proper polarity without grounding cculd cause spuricus 10
cperation, no further evalu6 tion is necessary, except for circuits involving high/ low pressure interfaces.
1 The licensee has rcuted circuits invciving high/ low pressure interfaces in i
dedicated rigid steel cerduit.
In addition, there are procedures that require the circuits to be deenergized ir. the event of a fire.
The circuits can be deer.ergized frcn the n.ain control rcoa. ar.d the emergency switchgear rooms.
The likelihecd of getting a het short of the proper polarity withcut grounding of two independent de circuits (one circuit withir a dedicated ccr.duit and one circuit from cuiside the conduit) is ccrsidered sufficiertly low as ret to require evaluatien.
Based cn the above guidar.ce contained in GL 86-10, an exemption request #cr the above circuits is not required.
5.4 Conclusjon Based on the above evaluaticn, it is concluded that the 4-20 mA instrument cables and the 125-Vdc circuits identified in the licensee's subnittais neet the guidance contained in GL 86-10.
Therefore, the exemption tequest # rem protect'ng the circuits fron,bct shorts is nct required.
i
\\
6.0 SEFARATION OF INSTRUMENTATION INSIDE CONTAINMENT 6.1 Exemption R_equested An exemption was requested from the requirentnts of Section III.G.2.d to the exter,t that it requires redundant cables and equiprent separated by 20 feet free of intervening ccabustibles or by radiant energy shields.
6.2 Djscussion The licensee has stated in exenption request 17 that primary and alternate trains of cabling for primary plant instrun.entation inside the containment are separated by more than 20 feet or by radiant energy shields, but intervening cenbustibles exist in certain areas.
The instrumentation of concern are the reactor coolant system (RCS) het and cold leg temperatures, steam generator level, excore neutron flux monitoring, RCS pressure, and pressurizer level.
Fire Areas 15 and 16 are the primary centainments for Units 1 and 2 respectively.
Primary ard alternate trains of instrumentation are routed through two different penetration areas within each containment.
One electrical peretration area is into each unit's cable vault / tunnel area.
A second electrical penetration area for each containnent is provided into the fuel building. These two penetration areas are separated by more than 70 feet hcrizontally and by more than of 30 feet vertically fer each unit.
Radiant energy shields have been installed between primary and alternate instru-n'entation or components located less than 20 feet apart. Fire rated conduit wraps have been provided where there is less than 70 feet of horizontal separa-tion, regardless of the cpen vertical exposure.
The wraps are provided urtil a distance of 70 feet of horizontal separation is achieved or until a barrier which is constructed cf heavy concrete is encountered.
Intervening cerbustibles in the form of cables trays exist between primary ard alternate trains of instrunentatien separated more than 20 feet or by radiant energy shields.
In order to nitigate the potential cf fire spread along the trays, the licensee has installed vertical and horizcntal fire stops where the cable trays constitute a potential intervening conbustible between safe shutdewn cable trays. The horizontal fire steps are 36 inch-long i:arinite beards on the tcp and bottom of the tray, with 10 inches of silicene foam in between.
Cable tray covers have been installed on trays near the cable vaults / tunnels penetration areas.
In addition, a cable tray botton has been installed en the lowest horizental cable tray.
Feat and smoke detectors which alarm in the control reem are located in certain areas within the primary centairment.
Portable fire extinguishers are also located inside the containnent.
Dry stardpipes are available for use by the fire brigade.
4 e
6.3 Evaluation
~
Th2 fire protection for Fire Areas 15 and 16 does not comply with the technical requirements of Section III.G.2.d of Appendix R because intervening combustibles, specifically, cable in trays, exist between primary ar.d alternate trains cf cabling for primary plant instrunentation, which is separated by more than 20 feet.
The licensee has connitted to provide fire stops between redundant instr'umenta-tien components or cabling to mitigate the consequences of intervening conbustibles.
The combustible leading in the containment is limited, and limited access to the containment n.inimizes the transient combustibles which cculd be introduced.
The 1ccation and design of the fire stcps will inhibit fire propagation between redur. dant trains along the cable trays. Uith the fire protecticn features described abcVe, there is reascnable assurance that a fire within the contain-ment will not prevent the plant from safely shutting down.due to loss of primary and alternate trains of identified instrumentation cabling resulting from fire prcpagation alcr.g intervening combustibles.
6.4 Conclusion Based on the above evaluation, the staff concludes that the existing fire pro-tection features combired with the proposed cable tray fire steps provide a level of fire protection equivalent to the technical requirements of Secticn III.G.P.d of Appendix R.
Therefore, the exemption request from the specific requirements of Appendix R requiring no intervening combustibles should be granted.
i 13
j 7.0 AUXILIARY BUILDIhG, VENTILATION EQUIPMENT AREA (FIRE AREA 17) 7.1 Exempt io,n, Recto,e,s,t ed An exemption was requested from the requirerrents of Section III.G.P.b to the extent that it requires automatic detection and suppression throughcut Fire Area 17.
7.? Discussi,on The licensee has stated in exemption request 18 that Fire Area 17 for each unit does nct rceet the requirenents of Section III.G.E.b because full area automatic detection and suppression are not provided.
Fire Area 17 censists of the auxiliary, fuel, ard decentamination buildings for betn Units 1 and 2.
The buildings are located side by side in a north / south orientatien, with the auxiliary building to the south, the decontamination building to the north, and the fuel building in the center. Additional details concerning Fire Area 17 are provided in Section 2.0.
Elevatien 45 feet, 10 inches of the auxiliary building contains the rcrmal auxiliary building exhaust fans, certainment purge supply fans, miscellanecus supply and exhaust fans, ard the ventilation system charcoal filters.
/uxiliary building ventilation is required to naintain a tenable environment for personnel and equipment during plant shutdown.
Redundant fan systerrs are located en elevation 45 feet, 10 inches, separated by at least 20 feet horizertally, on cpposite sides of charcoal filter units.
The licensee has modified the power and the control cables of redundant fans so that redundant cables are separated by rcre than 20 feet of horizontal distance and routed in conduit.
The primary combustibles en elevation 45 feet, 10 inches are three charcoal filter units, two of which are 1ccated in the center of the floor between the two fans. The licensee stated that the charccal filters will not expose either fan fer the folicwing reasons:
1he filters are within tretal enclosures and can be isolated by remotely cperated redundant darrpers.
The filter enclosure is equipped with both a safety-related arrbient terrperature monitoring systern and a standard fire protecticn heat detection 1
system, each of which annunciates in the control recm.
There is a trarvally actuated 1cw-pressure carbcn dioxide fire suppression system in each charcoal filter enclosure.
The systems can be actuated 1cca11y, near the filters, and terrotely, freni the control room. The third charcoal filter is protected with a water-spray deluge system.
ia l
1
An 18-inch-thick wall, 7 feet it'1, surrcur.cs uch filter, and acts as a radiaticn shield atd a partial fire barrier.
The walls also act as partial height walls between the fars.
Any cable trays which would be considered intervening ccnbustibles between the fans will be firestopped.
7.3 Evaluation The lack of area-wide fire detection ard suppression is a condition ercorrpassed by the revised interpretaticns of Appendix R contained in GL 86-10. Accordirg to these interpretations, nc exemptions for this condition is necessary.
Mcw-ever, the staff ccr.siders the evaluation are justificat u for the exerptions submitted by the licensee as constituting the fire hazards aralyses required by the GL.
The staff's principal concern was that because the absence of area-wide auto-catic suppression and detection systems, a fire of significant regnitude ceuld develop and dar. age both the nornal ard redundant auxiliary building ventilaticn fans. Fewever, the cerrbustible leadir.g in Fire Area 17 is low, resulting in an equivalent fire severity of less than 70 minutes hsed en the ASTM E-119 time-tertperature curve.
In addition, auturatic fire detectors are installed cn each elevation cf the auxiliary building near cable trays and in each charging purr.p ctbicle.
Because cf the presence of the detectors, a fire would be detected in its incipient stage. The alarrns frorn the detecters are annurciated in the rnain control recr;.
The fire brigade would be dispatched to extinguish the fire u.anually, usirs hcse lires or portable extingeishers.
The primary ccmbustibles en the 45 foot, 10 inch elevation are the charcoal filters. The two filters in the center are pretected by a trarual carben dicxide fire suppressior. system that can be actuated either locally, rear the filters, or terretely, frorn the control recm.
The third charccal fi'.ter is protected by a water-spray deluge system.
The charcoal filters are contained within a rretal enciesure equipped with dartpers, and are erciosed by a partial height wall that has a fire rating that exceeds 3 h9 rs.
The steff finds that the installation of area-wide autorratic fire suppression and detection systems would not significar.tly increase the level of fire pro-tection fer Fire Area 17, 7.4 Conclusion Based en the above evaluation, the staff concludes that the licensee's analysts and justification for the absence of area-wide fire detection and suppressien in the subject areas are in conferrence with the guidance issued in GL 86-10 ard are, therefore, acceptable.
15
8.0 EMERGENCY LIGHTING IN ThE C0hl AIM 1ENTS, CONTROL ROOM, AND EXTERIOR ACCESS ROUTES 8.1 E> erp,t,io ns_R,eque s ted Exempticos were requested frem the requirements of Section II:.J to the extent that it requires all areas required for operaticr. of safe shutdcwn ecuipment, ard ir, access ard egress routes thereto, to be provided with emergency lighting units with at least an 8-hcur battery supply.
8.? Discus si,o,n The licensee has stated in exemption requests 14, 21, and 23 that the above areas de ret n+et the requirements of Section III.J of Appendix R because 8-hcur battery-pcwered emergency ligttirg is not installed.
The control reem emergency lightirg units 7.re c'esel-pchered as opposed to an 8-hcur battery-pcwered supply.
The licensee's basis for the use of diesel-backed energercy lighting in the control room includes the following:
1.
The plant energency diesel generators have a fuel capacity in excess of 8 hcurs.
2.
Pcwer feeds are routed such that no single fire outside the control rocm cculd affect bcth power supplies for the control reem lights.
3.
The lights are arranged in a configuration such that the lights from each units' dit3e1 cover both sides of the control room, d.
An illumination test has been perforn+d to verify the adequacy of the lighting level to perform required opertt' ens when powered frem either diesel.
Curing the short transition frem loss of offsite pcwer to diesel generator pcwer, battery-powered lights will illuminate the centrol rcen.cceplex.
Operator access routes to varicus safe shutdown conponents required for an Appendix R safe shutdown may require travel cutside the buildings.
Lighting for the exterict rcutes is prcvided by station security lighting.
The security lightirg is powered by the station security diesel in the event cf less cf off-site pcwer.
Safe shutdckn components are lccated within several buildings that require exterior access. These buildings are the nain steam valve areas and the AFil l
rocms fer Units 1 ard 2.
i The reactors' containnents Fire Areas 15 and 16 for Units 1 and 2 respectively, are reinforced concrete buildings which house components of the ruclear steam supply system.
~
16
The floor elevations in the containments are 77 feet, 7 inches; 13 feet, O inch; 3 feet, 6 inches; 18 feet, 4 inches; and 47 feet, 4 inches.
Access to the con-tainments is through a personnel access lock from the auxiliary building on elevation 47 feet, 4 inches.
Access within the containments is via walkways tha* circle the containment between the outer containment concrete wall and the interior shield wall.
The licensee's procedures for an Appendix P. shutdown in the event a fire will be based on establishing a letdown path.
To ensure adequate pressure control of the RCS, the letdown path may be required to be established within approxi-mately 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
If all the chemical and volume control systems (CVCS) normal and excess letdown paths are unavailable due to fire damage to the necessary cabling, the licensee's shutdown procedures will identify an alternative letdown path, which may be established by marually aligning the recuired valves.
Some of the valves are located within the reactor buildings' containments and will require containment entry by operators to manipulate the valves.
Establishing letdown is the only Appendix R "hot shutdown" scenario requiring access to the containments.
The reactor buildings' containments are not equipped with standard emergency 8-hour duration battery-powered lighting units.
The installation of emergency lighting is not feasible due to the effects of the extreme temperature, humidity, and radiation conditions on the lighting units inside containment.
In addition, frequent periodic testing of emergency lighting inside containment would not be consistent with ALARA criteria and could only be performed during outages, which would not provide a frequency that could assure proper operation.
Portable battery-powered lanterns are stored under administrative controlled conditions for use in emergencies, such as an Appendix R event.
The lanterns are under the periodic test program to assure that the proper number is available erd that they are all in working condition.
Fixed emergency lighting units (8-hour battery-powered units) will be installed in the auxiliary building to provide illumination up to the airleck into the containment.
8.3 Evaluation The fire protection in the above areas does not comply with the technical requirements of Section III.J of Appendix R because 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> battery-powered emer-gency lighting is not installed in all areas needed for operation of safe shut-down eouipment and in access and egress routas thereto.
The staff had several concerns with the licensee's proposal to rely on portable lights.
The first was that the flashlight would not be maintained in an operable condition for use in an emergency.
However, the licensee conraitted to control access to and to maintain the flashlights so as to be assured of their avail-ability and operability when needed, 1
The staff was also concerned that there might be obstructions or tripping hazards in the route of travel that night not be revealed with the beam of a flashlight.
Based on past observations of the proposed route, no such conditions exist.
17 i
l e
Firally, the staff was concernea the in proceecir.g acrcss plant areas or in performing shutdowo tasks, the operator would be required to use both hands, which would effectively arevent hin, from using the flashlight. Mcwever, the licensee has indicated t,at no such actions are necessary.
On this basis, the staff censiders the licensee's use of flashlights to be acceptable.
The staff also had several concerns with the licensee's preposal to rely Ucen security lightir.g.
The first was that the same fire which resulted in the need to go to the areas covered by the security lighting would cause the loss of this capability.
The security lighting is supplied power frem the security diesel ard is, therefore, not vulnerable to fire loss under the postulated fire scenario.
Ancther concern was that the level of illumination would be sufficient to provide the staff with reascrable assurarce that the safe shutcown function eculd be achieved.
The licensee corducted a walkdcwn of the yard areas where. the alter-native lighting configuraticn was provided. This walkdcwn ccnfirr:.ed that an adequate level cf illumination had been provided.
The staff was also concerned that the security lighting would not be maintained.
I'cwever, this lighting is inspected and rnaintained as part of the plant security requirernents.
The staff finds this acceptable.
S.A Conclusion Based on the above evaluation, the staff considers the licersee's alternate lighting configuration tc be equivalent to that achieved by confern.arce with Appendix R to 10 CFR 50.
Therefore, the licensee's request for exemption from the requirements of Section III.J. in the subject locations shculd be granted.
18
9.0 REFUELING WA1ER STORAGE TANK, DIRECT READINGS 9.1 Exerrpti n,,Rego,e,s,t.ed i
An exemption was reques+ed frcm the r equirerent1 of Sectier. III.L.7.d to the extent that it requires that process tronite.rine to be capable of providing direct readings of process variables necesner to perform and control rtquired safe shutdown functions.
9.2 Nscussien The licensee has stated in exenption request 72 that the level nonitoring cf the refueling woter storage tank (RKST) does not rect the requirerrents of Section III.L.P.d because a fire cccurring in ar) cne of several fire areas such as the ccr,trc' recir,er the emergercy switchgear room may result in the less of RWST level indication.
An RWST is provided for each unit.
The RWST provides makeup water to the RCS via the charging pumps for reactor ccolar,t intentory anc reactivity control.
Level indication for the RWST is provided in the control rocm for normal opera-tions. A fire in the control rocn: and either units' energency switchgear reor er cable vault / tunnel could cause the loss of this irdication.
No redundant er alternate n.ethed is provided for obtaining either a direct er indirect level indication.
Plant Technical Specificaticns require that 3F.7,100 gallons of water be available in the RPST of each unit operating. The licersee has perforrred an aralysis and deterr. ired that less than 10 percent of the solume of the RUST is required to reach cold shutdcwn.
The twe RWSTs are cross-connected so that the charging purps for the two units take sucticn frcm a header fed by both tanks.
The RWST ct oss-cenrect valves are air-cperated, ard fail epen on loss of air.
There are ac'n.inistrative controls to ensure that if cne unit is not operating, there will be sufficient volone in that unit's RWST to safely shut down the cperating unit should the operating unit's chargirg pumps becerre disabled. This shutdown wculd be achieved using the charging punp discharge cross-cennection.
9.3 Evaluation The fire protectier: fcr the RWST does not cor9 ply with the technical requirerrents of Section III.L.T.d of Appendix R because a fire can darrage RWST level indica-tion ard no alcernate neans cf process ronitoring is provided.
Therefore, 3
direct readirgs of the process variables necessary to perform and control required functions at the control rocni and the rencte shutdown panel is ret provided.
19 i
i The amount of water taken fron the RWST for RCS rakeup durina an Appendix R safe shutdown is 1bss than 10 percent of the minimum RWST volume allcwed Sy the licersee's Technical Specificatiens.
1 The RWSTs are cross-connected so that the total volone of both tanks is avail-eble, or a backup supply of cre RWST if one RWST is cut of service. Administra-tive controls are provided to assure that there is sufficient quantity of water available in the RWST of a unit that is not operating to supply the charging purps for the operating unit if necessary.
There is sufficient cargin of RHST volume to achieve an Apper.ciy R safe shutdewr..
9.4 Conclusion Based on the abeve evaltatico, the staff concludes that the existing RWST inven-tery conbired with the administrative centrols and the quantity of water avail-abie ir. the RWST of a unit not operating provide a level of fire protection equivalent to the requirements of bection III.L.2.d of Appendix R.
Therefore, the exemption request from direct reading cf process variables, specifically, RWST level, shculd be granted.
20
a 10.0 TURBINE BUILDINGS (FIRE AREA 31) 10.1 Exempt ioMe,q,ue,s,t,ed, An exemption was requested from the requirements of Secticr. III.G.P.b to the extent that it requires fire detection to be provided thrcughout fire area 31.
10.2 Discuss io,n, The licensee has stated in exemption request 3 that Fire Area 31 does not meet the requirerents of Section III.G.P.b because fire detection is net provided thrcushcut the a na.
Fire Area 31 is the turbine butiding.
This building consists of three 9 feet, 6 inches (basement); 35 feet, O inches (mezzanine) primary elevations:
- and 58 feet, 6 inches (turbine deck). The service building is located north of the turbine building. The administration building is to the west, the ccndensate polishing building is to the east, and the south wall is an exterior wall facing the transformers.
There is an S inch-thick block wall that extends up from the floor of the 9 foot, 6 inch elevation to the ceiling of the 35 foot, O inch elevaticn.
This wall seperates the Unit 1 areas from the Unit 2 areas in the turbine building. Th(re is a pipe tunnel that starts at the 9 foot, 6 inch elevation of the turbine butiding. The tunnel is the subject of exemption request 15, which is discussed in Section 14.2.6 of this SE. The 9 foot, 6 inch elevaticn houses the punps and the lute oil components.
The turbire building centains the auxiliary steam system to the air ejectors, l
which are required for alternative safe shutdown if the PCRYs are incperable, and several main steam valves which are required for alterrative safe shutdewn if the mair, isolation valves are increrable.
The turbine building also contains nanual isolatict valves for the charging pump service water system. The salves are located in valve pits below elevation 9 feet, 6 inches in each unit's turbine building.
The ficw path for the charging pump service water system is such that either Unit 1 or 2 charging punp service water piping can supply water to the charging tap service water pumps for each unit.,
The turbine building has a full erea automatic sprinkler system on elevatiens 35 feet, O inch and 9 feet, 6 inches.
Upon sprinkler system water flow, an alarm is transmitted to the control rocm.
The major lube oil components have irdividual deluge systems actuated by heat detectors over the hazard.
The detectors also arrunciate in the control room upon systee actuation.
There are several portable fire extirguishers and hose stations located in the turbine building. Also, there is a portable fire fighting foam cart available.
21
10.3 Evaluation Thelackofarea-ddefiredetectionisaconditionerccmpassedbytherevised interpretations of Appendix R contair.ed ir GL !S 'C.
According to these inter-pretations, no exemptions for this condition is necessary.
Fewever, the staff censiders the evaluation and justification for the exerr.ption submitted by the licensee as ccostituting the fire hazards aralysis required by the GL.
The staff was concerned th>' because an area-wide fire detecticn system was not installed, a fire of significant thagnitude could develcp and damage safe shutdown equiprent.
Mcwever, elevaticos 35 feet, O inch and g feet, 6 inches of the turbine building are fully protected by autcinatic sprinklers.
The major lube oil components in the turbine building have individual deluge systems actuated by heat detectors over the hazard. Water ficw in a sprirkitr system annunciates in the contr,1 rocm. The licensee has stated in their evaluation that, in the turbine building, flamirs fires are trcre likely to occur than smoldering fires. They also stated that sprinklers have a capability tc detect flaming fires which is certparable to that of fbed terperaturE heat detectcrs.
The licensee has dancnstrated by this evaluation that the installed sprinkler systerrs ard the arrangement of safe shutdown equipnent in the turbine building provide a level of fire protection which would nct be significantly increased by the installation of an area-wide autcmatic fire detection system.
10.4 Conclusic,n Based on the above evaluatien, the staff concludes that the licensee's analyses and justification for the absence of area-wide autctratic fire detection in the subject area are in conformance with the guidance issued in GL 86-10 &nd are, therefore, acceptable.
1 i
2?
5 a
I 11.0 PECHANICAL EQUIPMENT ROOM 3 (FIRE AREA 45) 11.1 Exerrptionle,qgested The licensee requested an exerrpticr froni Section III.G.3 of Appendix R to the extent that it requires a fixed autcrratic fire suppressien systerr te be installed thrcughout Fire Area 45
'1.7 D_iscussion Tre licensee has stated in exemption request 5 that Fire Area 45 for each a.iit does rot teet the requirerrents of Section III.G.3 because full area autcrratic fire suppressior, is nct provided.
Fire Area 45 censists of rnechanical equiptrent rooni 31ccated in the service building baserrent at elevation 9 feet, 6 inches. The Unit 2 energency switch-gear room bctders on the ncrth and west ar:d is separated fron. Fire Area 45 by an 18 inch-thick reinforced concrete wall.
The south wall is a 04 inch-thick reinforced concrete subterranean exterior wall.
The f1cer is of 6 inch-thick cercrete en grade and the ceiling is cf 6-ir.ch-thick ccr. crete slab.
Fire Area 45 bas an area of approximately 900 square feet.
It is entered by a 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> rated class A fire door frorr the L' nit E er,ergency switchgear reer.
The rect has several ventilaticn openings protected by 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> rated donpers.
Cable penetrations through the walls are sealed with 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> rated fire step material.
Administratise centrols prcvide for periodic observaticn cf the penetration seals.
Fire Area 45 centains dry air bottias for control rocm errergency pressurizatier.,
as well as for the chiller units and related purrps, piping, and cabling.
Post irrpcrtant are the charging purrps, service water pumps, and the safe shutdewn-related cabling passing thrcugh the area.
A 24 ircF-wide ficcd barrier is 1ccated just inside the door.
It is designed to protect the energency switchgear room frem a pipe or pump failure in Fire Area 45.
Two sets of srnoke detectors are provided in Fire Area 45.
One set is the criginal fire alarm system which annunciates in the control recm. part of A seccnd set of detectors were installed as part of a charging purrp-service water pump redundancy prefect.
The rew detecters are designed to opetate the moter-cperated valves and to allcw the redundant purps te operate in the event of a fire.
These detectors arounciate in the control room, but r.ot on the main fire alarm panel.
There are fire extinguishers in the area and hose stations are located in the turbire building at the dccr to the emergency switchgear room.
Fire Area 45 contains twc charging purrps, service water pumps, ard associated 23
power and control cables. Also in this fire area are the power and control cables fcr the three energe.sc) diesel generators.
Fchever, the pcwer and con-trel cables for diesel generetor I have beer relecated to a separate fire area.
Power and ccntrol cables for Unit ? motor-driven ARI pumps are occated in this area.
Fewever, the turbine-drive. AFW pump would be available for safe shutdchn of Unit F.
The fixed corr.bustihie iceding in this area is 1cw to moderate, consisting of cable irsulation and a small quantity of lu't oil for the pumps.
A fire in Fire Area 4E has the potential te damage the purps ard cables for the redurdant charging pump-service water purps. Altutucive shutdown capability is previded by using charging purp-service water purps located in a separate fire area.
11.? Evaluation _
The lack of area-wide fire suppression is a condition encompassed by the revised interpretations of Appendix R ccntained in GL ~6-10.
Accordin interpretaticos, no exerption for this condition is necessary.g to these Fewever, the staff ccrsiders the evaluation and justification for the exemption submitted by the licensee as ccostituting the fire hazards anaTysis required by the GL.
The staff's principai concern was that if a fire occtrred, the lack of an area-wide fire suppression system could result in significant fire ropagation and duraticn and adversely affect the post-fire safe shutdown capasility. Fewever, the ccrbustible icading in this area is Icw to mode ate, consisting primarily of cable irsulation and lube cil.
If a fire were to occur, it is expected tc develep slcwly.
Smoke detectors are pcvided in the area.
The alarm for these detectors are anrurciated in the main control recm.
The fire brigade will be dispatched and will extinguish the fire nanually, using the hose lines er pertable extinguishers previded.
Alternative shutdcwn capability is provided by using charging purp-serv're water pungs iccated in a separate fire area.
Until the fire was extinguished by the fire brigade, the low to moderate com-bustible loading, the fire detection, and the availability of alternative shut-down capability in a separate fire area will previde sufficient protection to issure that a fire in Fire Area 45 will not prevent a plant safe shutdcwn.
A Cenclusion Basad on the above evaluation, the staff concludes *at the licensee's analyses and justification for the absence of area-wide autentic fire suppression in 3
the subject area are in confor.mance with the guidance hiued in GL 86-10 and are, therefore, acceptable.
1 l
24
12.0. RECUNDANT CIRCUITS IN A MANHOLE
'd.1 Exemption R,e_ quested An exemption was requested from the specific requirements of Section III.G.2.a to the extent that it requires the separation of cables, equipment, and asso-ciated nonsafety circuits of redundant trains by a fire barrier having a 3 bcur fire resistance rating.
12.2 Discussion The licensee has stated in exemption request 25 that the power feeds to the six emergency diesel generator fuel oil transfer pumps (two pumps for each of three diesel generators) are routed through the san'e manhole and that the pcwer feeds de net reet the requirements of Section III.G.2.a because the feeds for redundant purps are not separated by a 3 hcur fire barrier.
12.2.1 Area Oescription The manhole is 1ccated in the north yard area adjacent to the scuth wall of the fuel oil pump bruse, room 2 (Fire Area 1FB).
It is approximately 6 feet by 5 feet 4 inches wide (32 square feet) ard 14 feet deep (from the tcp of the niarhole to the top of the ficor).
The walls, floor, and ceiling are a miniram cf 24 inctes of ret fcrced concrete.
The manhole cover is approximately h
1 inch-thick steel alate.
The function boxes (JBs) through which the acwer feeds pass are embedded in con-crete en all sides, except the one facing tie ir. side of the mar. hole.
The JEs are of galvarized steel. Two boxes are or the best wall ard the other two are en the east wall.
The fuel oil punp house located to the ncrth of the nanhole is divided into two separate rooms, which are different fire areas (16A and 188).
There is a 3 hcur rated barrier between the maritole and the fuel pump house rocms.
The north yard area centains the structures associated with the primary side cf the plant (containment structures, fuel building, which results in limited safeguards, etc.).
This area is part of the restricted controlled areas (RCA,
access.
There are no detection or suppressier. systems within the manhole. However, yard hydrants and bcse hcuses are 1ccated rrarby.
12.2.2 Configuration of the Hanhole The pcwer feeds for the fuel oil transfer pumps are routed via buried conduit into functicn bc>es within the narhole. A fire in the manhole concurrert with the loss of off-site pcwer has the pctential of affecting the energency peker system by fsiling to provide additional fuel after the 3 hcur supply in the diesel generator day tank is exb'usted, i
25
, s The JBs are buried in concrete such that only one face is exposed to the inside of the manhele.
In addition, the JBs are on opposite sides of the man-hole, separated by 6 feet with ro intervening combustiblas.
To upgrade the separation Letw(n the JBs, fire-rated silicere foam has been used to ccm-pletely fill them.
This arrargerent serves several purposes:
1.
The foam has sealed the conduit peretrations into the JBs, preventing smoke anc heat frem enterirg.
2.
A fire inside a JB must burn through the foam, then through a galvanized steel platc tc be able to expose the other JBs, which are 6 feet away.
3.
A fire entering the manhole n.ust cause both of the galvanized steel-faced plates to fail, and then must burn through several inches of silicene RTV foam before a cable is expcsed.
The mantcle construction is as fo11cws:
1 The walls, floor, and ceiling are of 74 inch-thick reinforced cencrete with no cpenings to other fire areas, except via the JBs and ccnduit which, as ncted above, are sealed.
E.
The roof of the manhcle is approximately 8 inches above grade. Due to the large area of the north yare' and the presence of storm drains, it is treenceivable that there could be a spill cf sufficient volume to overflow the 2-irch lip.
3.
The access hatch is constructt? of 1 inch-thick steel plate.
The plate fits securely into a recessed spening.
A.
The manhole is approximately 11 feet deep and the junction bcxes are abcut 4 feet above the floor.
D e coiline height will reduce exposure to the JBs.
A fire in the manhole cr 1earby wou M be detected by the security officer in the guard tcher located naarby.
The fire brigade could quickly extinguish fire in the manhole or i.a rby, either wit.h a portable extinguisher or with a hese stream from a nearby hydru.t and hese house.
1?.T.3 Cutside Exposures Cue to the lack of combustible' # thin the manhole, the only credible source of expcsure to the pcher feeds is fvcm a fire criginating cutside of the manhole.
The pctential scurces are lhts', below along with mitigating factors.
1.
Fuel Oil Pump Houses The fuel oil purphouses are located adjacent to the manhcle on the ncrth side. The barrier between the pump hcuses and the manhole is 3 hcur rated, and the conduits have been effectively sealed where they enter the JBS.
In addition, both roorr A ard D of the pump hcuses have separate high pres-sure CO,. tctal f1 ceding fire suppression systems actuated by heat detecters.
The s) stem annunciates in the control room.
Therefore, the fuel oil pump hcuse does ret pcse an ext;csure threat to the ranhole.
26
i s 2.
Abcve Grouno Fuel Oil Stor. qe Tank.
There u, a E10,000-ga11on Nel oil storage tank located approxtrately 50 feet (on center) from the trarhole.
There is a dike arcund the tar.k designed to hole the volurre cf the tank. The station fire brigade is equipped with foam carts and foam rozzles for trarual fire fightirg cpera-tions. The manhole roof is 8 inches above grade.
If the dike failed, there is insufficient vclure in the tank to flow into the manhole.
(Note:
The tank trucks that supply the fuel cil tank off load outside the security fence over 500 feet from the trarhole).
3.
Transient Flarrenable Liquids.
There are few sources of flarrrable ard ccmbustible liquids in the ncrth yard.
The largest scurce is the fuel in vehicles. Sirce this aree is part of the RCA, there are health physics controls or vehicles brought into the areas; therefore, crly a liraited nutber enter the area.
The sate restrictict.s apply to material carried by hard into the RCA. As stated above, the F irch differerce betbeen the top of the tranhole and grade will prevent spills from entering the tranhole.
Therefore, the 24 inch-thick concrete construction, the solid steel access hatch plate, and the 8 inch difference between grade ?cyc1 erd the top of the manhcle will prevent cutsidt o pesures irca entering the ranhcle.
12.3 Evaluati_on The fire protection for the manhole dces not cornply with the technical require-rents of Section III.G.T.a of Apper. dix P because pcwer feeds to redundant fuel oil trarsfer pumps are oct separated by a 3-hcur fire rated barrier.
The cables are separated by JEs located en cppsite sices of the ranhole, approximately 6 feet apart with rc intervening cenbustibles. The cables are arrar.ged such that one ECG will be available if cne set of JBs were lost.
The JEs are embedded in the wall such that only cre face is exposed.
The JBs have been filled with silicone foam to seal the cerduits enterirg the bcx and to prevent the fire from spreading cut of the JB.
The potential espesure hazards located nearby are mitigated by either dikes er fire suppression systerns.
The arrangement of the JBs in the tranhole, the separation between the JBs, ard the low cerrbustible leading in the tranhole prcvide reascrable assurance that at least ene t'ain of fuel oil transfer purrp pcwer cables wculd rerrain free of fire darrage.
- 10. t-Cerclusion Based on the above evaluatien, the staff concludes that the existing fire pro-tecticn features provide a level of fire protection equivalent to the technical requirements of Section III.G.P.a of Appendix R.
Therefore, the exerrption request for the lack of a 3 hcur fire-rated bart'er between the pcwer feeds in the narbele shculd be granted.
77
i s U.0 FIRE AREA BOUNDARIES i3.i b enct io,n,sJ,e,q_ue s ted The licensee requested approval fer a nurrber of exenpticns from Section III.G.2 of Apperdix R to the extent that it requires separation of recundant safe shut-dcwn systems by 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire-rated barriers.
The ccoditions erccmpassed by these exenptions exist within the walls and ficor/ ceiling assentites khich ccostitute fire area boundaries.
In the interpretations of Appendix R certained in GL E6-10, the staff indicated that rc exenptions were necessary for ncn-fire-rated features in fire area bourdaries.
Hewever, a fire. hazards analysis was required for each condition which cculd either be submitted to the staff for review cr kept en file fcr future audit.
The staff considers the exerption re-cuests as constituting the fire hazards analyses.
13.2 Discussion 13.2.1 Emergency Switchgear Room Fire Ccor Frares. Fire Area 4 The licensee has stated in exenption request 7 that one door asserrbly (fire dcct 21) in the energency switetgear fire area boundary at elevatien 9 feet, 6 inches is not fire rated. The door is located between the emergency switch-gear recr. (Fire Area 4) ard the turbine building (Fire Area 3').
Fire Cccr T' is a double dcor with an astragal between the leaves. The doer serves as the primary access frcra the turbine building and Units 1 and E errer-gency switchgear reces.
The dcor is equipped with a security access certrol card reader.
The dccr leaves arc 3 hcur rated. UL labeled, Class A fire dccrs.
The licensee has determined that this fire decr asserr.bly aisc ccnststs of the fellcwing corrponents:
Merlabeled steel channel frane in a reinforced concrete wal' Nenlabeled steel transom above the door Cenduit into the frarne (astragal).
The errergency switchgear rooms are protected by snoke detectors which arnunciate in the train control rocn, In addition, a total flooding Halen fire suppressicn system has been installed.
The turbine building, elevation 9 feet, 6 inches has an autcratic sprinkler system installed throughout the area.
Sprinklers are also installed throughcut 1
elevation 35 feet, O inch. There are several fire extinguishers located throughout both areas. Hose stations are located in or near both areas.
The 'icensee has perforred ar aralysis evaluating the capability of the decr to perforrr ir the fire area beurdaries based en the installed fire protection systerns, cenbustible quantity and configuratien, ard the carparison of existing door asserrblies with labcratorf standards.
4 28
i.
e s 5 e
14.2.2 Fire Coors, Fr6r..es hut Fire liated (Varnus Fire Areas)
The licensee has stated in exenption request 6 ths,t several door asserblies in fire area boundary walls have franes which do not tave a label frem a reccgnized testirs laboratory.
These frames consist of steel charnels that are an integr61 part of a reinforced concrete wall.
Tre licenses has perforr,ed an aralysis which shcws that the frames are equivalent to labeled frares due to their cc.nstruction. Additionally, the conbustible quantity and configuraticrs and fire plotecticn systems on each side cf the door was consic'ered.
The subject decrs are as fc11ews:
Cecrs 14 and 15 Ccers from the centrol roca cceplex (Fire Area 5) to the turbine building (Fi;e Area 21)
Cects ?7, 39, and 41 Decrs from the emergency diesel gererator roces (Fire Areas 6, 7, and 8) to th9 turbire building walkway (Fire Area 31)
Cecrs PS, 26 -
Ccors from the Ur.it 1 en4rgency switchgear reem (Fire Area 3) to the Unit 1 cable vault / tunnel (Fire Area 1)
Deer 27 -
Coor from the Unit 2 emergency switchgear roon (Fire Area 4) to the Unit 2 cable vault / tunnel (Fire Area 2)
Coor 24 A -
Ccor from the Unit 1 cable vault / tunnel to the auxiliary building (Fire Area 17)
Cecr 27 C -
Ccor from the Unit 2 cable vault / tunnel to the auxiliary building Cecr 23 -
Dcor frcm bettery recm 2B (Fire Area 12) to the turbine building Cccr 12 -
Ccor from the Unit 2 cable spreading room (Fire Area 31) te the control rocm con, plex rear stairwell Eccr 51 -
Eccr from the technical sutpcrt center battery rccm (Fire Area 55) to the turbine building i
4 Eccr 52 -
Cecr from the technical suppcrt center MYAC rect j
to the turbire building j
l All of the above areas are equipped with heat detectors and/or srcke detectors.
Units 1 and 2 cable vaults / tunnels and cable spreading rooms are equipped with total flocding CO, fire suppression systems activated by heat detectors.
The 1
i emergency switetg6ar rocms are equipped with a ranua11y actuated Falon system.
A rarually activated total fleeding C0 system is located in the three emergency 3
1 29
a
(
^
diesel generator rocms. A rar.ually actuated deluge system is 1ccated at the tcp cf the cable vault and a manually actuated sprinkler systen is 1ccated in the cable turrel.
There are smcke detectors in the cable vaults / tunnels ard cable spreading room areas to provide early detection.
Sprinkler systems are irstalled throughout the lower two elevators of the turbine building.
In addi-tion, the lobe oil hazards in the turbine building, elevation 9 feet, 6 inches, are protected by automatic deluge systerns.
The cortrol roce, battery reem 2B, technical support center battery rocm and FYAC room, and the auxiliary building are equippec with acke detecters.
In additicr, the cable tunnel has a backup deluge systern and a closed-head sprinkler system that are manually activated.
Fire extinguishers are located throughout all the areas and hese stations are located nearby, 13.2.3 Fire Doors, Conduits in rect Frares (Various Fire Areas)
The licensee has stated in exerotion requests E, 9 anc 10 that a several deer assemblies in fire boundary walls have conduits penetrating into the door frame.
i The cerduits carry cable for security devices such as card readers or door monitcring. The conduit arrangeaant has not been tested fcr a 3-hcur fire ratirg.
The fire decrs insched include:
Dcor 20 Unit 2 ernergency switchgear room (ESCR) to the centrei room stairwell.
Coor 23 Unit 2 battery reem 2B (Fire Area 12) to the turbine building (Fire Area 31)
Deers 37, 39 ard 41 l' nit 1 cmergency diesel generator rocms (Fire Areas 6, 7, and 8) to the turbine building (Fire Area 31)
Cetection and/or suppression is provided in all areas adjacent to the abcVe deers. The conduits only peretrate cre side of the frare and where the cerduit and frate neet, all cetrections are tight.
The licensee has evaluated the affected fire door assentlies and determined that they provide an adequate cargin cf fire resistance considering the fire Icading and fire protection on both sides of each of the assemblies.
1 13.2.4 Control Rocm Stairwell /Erergency Switchgear Rocm Wall, Fire Barricr l
Rating (Fire Area 5) 1 The licensee has stated in Exemption Request 11 that the stairwell wall between the control room ccrplex (Fire Area 5) and the Unit 2 emergency switchgear rcce (Fire Area 4) is net fire rated for 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />.
The stairwell between the centrol room cceplex anc the Unit 2 erergency switch-1 gear room is ccrsidered part of the centrol rocm ccmplex fire area (Fire Area 5).
i 30
4
.t..
The wall between the stairwell ard the Unit 2 ernergency switchgear room (ESCR) is ccostructed cf F inch-thick masenry blocks. The licensee has perfortred er, analysis evaluating the capability cf the wall to perforn in this fire area beurdary based on the insta"ed fire protectier systems and acjoining spaces, the corrbustible leading configuration within the areas, and cerrparisor' with rasent) valls of kncwn fire resistance rating.
The evaluation ccncluded that the F inch-thick masenry wall prevides an adequate rargin cf fire resistance tased on the FRC staff guidance.
13.?.5 Cable Vaults /Tunrels and Auxiliary Eu11 dings' Wall Fire Barrier Rating (Fire Areas 1 and 2)
The licensee has stated in oertptier requests 10 ard 16 that there is at 2 inch-thick rascar) wall separating Units 1 and 2 cable vault /turrels (Firt: Areas 1 and 2) frcm each other that is r:ct a 3-hour fire rated wall, ard that there are an S inch-thick rascrry walls separatirg Fire Areas 1 and 2 frorr the auxiliary buildirg (Fire Area 17) at elevation 13 feet that are not 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire-rated walls.
The licensee has stated that the subject kalls are rated for a minimum of
? hours.
In addition, the cable vaults and turnois and the auxiliary building are equipped with steke detectors which will ar.runciate alarn> to the control rCer".
The cable vault /tur.r,el areas are equipped with autcrratic total fictding C0 fire suppressict systems and trarual sprinkler systerns.
2 The licensee concluded that the C irch-thick masonry wall ccirbined with the fire protecticr. fratures described above provide an adequate rargin of fire resistarce based on the NFC staff guic'arce.
13.2.6 Auxiliary Euilding/Turbire Euildirg Pipe Tunrel - Lack cf Fire Barrier Fire Area 17 The licensee has stated in oerptier request 13 that a pipe tunnel is 1ccated belcw the ground f1cor of the service building and provides a rcutirg from the turbine building (Fire Area 31) tc the auxiliary building (Fire Area 17) fer varicus pipes. A rated barrier er seal dces rct exist at either end of the tunnel.
The turrel has a 1cw cerbustible leading in the forru of pipe insulatien on chilled water lirts.
The tunr.el cpens vertically in the turbire budding at the ficcr level.
This elevatien of the turbine buildirg is equipped with an area-wide autcratic sprinkler system and deluge systems protect rajor lube cil corpcrents.
The certhustible leading in the auxiliary building is low to rsederate.
The P foot. O inch elevaticr. khere the tur.r el exits ir.tc the auxiliary buildirs contains few cables and cnly stall arrcunts of lute cil in purrps. The area rear the turrel in the auxiliary building is also protected by autcrratic sprinklers.
Sroke c'etecters exist en the auxiliary building side of the pipe tunnel.
There is a ? fcot-wide dike arcund the turbire tuilding tunrel cpening which presents flarrrable liquids from entering the tunnel.
i s 13.2.7 Conduit Passing Thrcugh Rated Fire Eartiers - Lack of Internal Seals The licensee has stated in exenptien request 24 that several cerduit penetra-tions thrcugh 3 hcur fire barriers between fire areas containing redundant safe shutdewn corrponents are r.ct sealed internally with a fire stcp material prcviding a penetration seal equivalent tc the iating of the fire barrier.
CL 06-10 provides guidance on conduit ard cable tray penetrations through fire barriers.
This guidarce states that cptnings thrcugh fire barriers Which separate fire areas sbculd be sealed er closed to provide a fire resistance rating at least equal to the barrier.
Operirgs inside conduits larger than 4 inches should be sealed at the barrier penetration. Cpenirgs inside cerduits 4 inches er less in diateter shculd be sealed at the fire barrier unless the conduit extends at least 5 feet on each side of the barrier and is sealed at both ends or at the barrier with ocncern-bustible material te prevent the passage of sincke and hot gases.
As an alterrative to the above guidance, the itcensee has proposed the fc11cwirg configurations for the internal sealirg cf conduit penetrations. The follcwing list of criteria are an acceptable deviation frcm cur guidelines.
1.
Cenduits are sealed internally at the fire barrier to the rating of the fire barrier.
2.
He cerduits are sesled en at least ene side of the fire barrier and both areas have fire detecticn r.eer the penetration.
3.
When the conduits penetrate a fire barrier and are unsealed, fire detection is installed in the vicinity of the ccnduit penetration en bcth sides cf the barrier, and the conduits terminate into ventless enclosures on at least cne side of the barrier, er 4
Vhere the corduits peretrate a fire barrier, the cenbustible icading has an equhalent fire severity of 10 minutes er less on ene side of the fire barrier and has fire detection rear the barrier on the other side.
In addition, the ccoduit terniinates into ventless enclosures cr. at least ene side of the barrier.
13.3 Evaluation The staff was concerned that a fire in any of these areas wculd perftrete the subject fire barriers resulting in icss of safe shutdown capability.
The existing configurations provide adequate passive fire protection, so that in event of fire, the barriers will not be breached.
Because of the fire pro-tection features provided, it is not expected that fire of significant tragnitude cr duration to occur in any of the fire areas.
If a fire dces occur, it wculd be detecttd by the installed detectors ard extinguished by the plant fire brigade er autcratic suppression systems before spreading to ancther fire area.
The staff concurs with the licensee's analysis of the above fire area bourdaries j
dencostrates the capability of the fire barriers to serve as fire area tcurdaries.
at
' ss g
-i 13.4 Conclusion Based on the above evaluation, the staff concludes that the licer.see's analyses and justification for ncn-3-heur-rated features in fire area bour.dary construc-tion conform with the guidance issued in GL 86-10 ard are, therefore, acceptetsie, 4
d I
a l
1 i
i i
33 i
g e,
14.0 Withdrawn Exemp,t,fon Request In Exemption Request 15 entitled "Establishing Letdown - Using f!cn-Shift Perscnnel" the licensee requested an exemption from the specific requirements of Section IV.L. A to the extent that it requires the nun.ber of non-shift personrel required to cperate hot shutdown equipt.ent anc systems to be en site at all tires.
Based on the results of further study and evaluttien perforced by the licensee, the licenste determined that sufficient tin:e and perscrr,el exist, after stable het shutdcwn is reached and the postulated fire is extinguished, for on-shift persenr.el te initiate letdowr. by valve lineups and other related activities if ncn-shift cperations personnel are nct available.
This is based on the evalua-tien that letdown will not be necessary for at least 10 hcurs after a postulcte.d fire discovery and unit trip.
Therefore, by letter dated October 16, 1987, the license decided to withdraw the above request for exerption.
i
?4 1
'6 O, O f 15.0 StJWARY Based on the evaluation, it is found that the level of fire safety in the areas listed belcw is equivalent to that achieved by compliarce with the technical requirements of Secticn III.G of Appendix R and, therefore, the licensee's request for exerrption in the fo11cwing areas shculd be granted:
1.0 Containment Incore Instrunent Tunnels, Fire Areas 15 and 16.
Lack of 20 feet of separatien between redundant excore neutren flux detector cables.
See Section 3.0 for additional information.
2.0 Separaticn of Instrun+ntation Containment.
Redundant cables and equipment separated by 20 feet or by radiant energy shields with intervening ccmbustibles. See Section 6.0 for additional information.
3.0 Redundant Circuits in a Panhole Less than a 3-hcur Rated Separation Barrier.
Lack of 3-hcur fire barrier separating redundant safe shutdown equipment.
See Sectien 12.0 for additional information.
Based on the evaluation, it is found that the level of fire safety in the areas listed below is equivalent to that achieved by compliance with the technical requirements of Secticn III.J of Appendix R and, therefore, the licensee's request for exemption in these areas shculd be granted.
1 Emergency Lighting in the Control Recn Erergency Lighting for Exterior Access Routes Emergency Lighting in the Containtrent Lack of erergency lighting units with at least an 8-hcur battery sur; ply in all areas needed for operation of safe shutdown equiprent and access and egress routes thereto. See Section 8.0 for additional information.
Based on the evaluation, it is fcund that the level of fire safety in the area listed bclow is equivalent to that achieved by compliance with technical require-rents of Section III.L of Appendix R and, therefore, the licensee's request for exerrption in this area should be granted:
1 Refueling K'ater Storage Tark.
Lack of direct readings of process monitoring variables necessary to per-form and control required functions.
See Section 9.0 for additieral infermation, 1
?
c... a, The following ccrditions confctm with the guidance issued in GL 86-10. Ne exemptions are, therefore, necessary.
1.
Emergercy Switchgear Rcce Fire Dcor Framcs (Fire Area a) 2.
Fire Coors, Frames Not Fire Rated (Various Fire Areas) 3.
Fire Doors, Ccoduit in Ccer Frames (Varicus Fire Areas) 4 Centrol Rocm Stairwell / Emergency SwiteF ear Cocm Fall (Fire Area 5) 5 5.
Cable Vaults / Tunnels ar.d Fire Barrier Rating Auxiliary Buildings' Fire Wall (Fire Areas 1 and 2) 6.
Auxiliary / Turbine Buildings' Pipe Tunnel Lack of Fire Barrier (Fire Area 17) 7.
Conduit Passing through Rated Fire Barriers (Lack of Internal Seals) -
Various Fire Areas S.
Lack of area-wide fire detection and suppression systems (Various Fire Areas) 9.
Lack of protection of icw current instrument circuits and 125-Y de circuits (Various Fire Areas)
Cated:
February 25, 1988 Principal Contr,i,b,u,t,c,rj D. Kubicki J. Stang b
4 1
1
.i I
b
-