ML20214G141

Draft Safety Evaluation Supporting Util 850401 Request for Exemption from 10CFR50,App R Requirements Re Fire Protection & Proposed Safe Shutdown Sys.Related Info Encl

ML20214G141
Person / Time
Site:	Fort Saint Vrain
Issue date:	11/18/1986
From:	Office of Nuclear Reactor Regulation
To:
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ML20214G112	List: ML20214G109 ML20214G141
References
TAC-54373, NUDOCS 8611250588
Download: ML20214G141 (35)

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UNITED STATES n NUCLEAR REGULATORY COMMISSION 7 $ yVASHINGTON, D. C. 20555

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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATING TO THE PROPOSED SAFE SHUTDOWN SYSTEM AND EXEMPTION REQUESTS CONCERNING 10 CFR PART 50, APPENDIX R FORT ST. VRAIN NUCLEAR GENERATING STATION PUBLIC SERVICE COMPANY OF COLORADO DOCKET N0. 50-267

1.0 INTRODUCTION

This Safety Evaluation addresses the compliance of the Fort St. Vrain Nuclear Generating Station (FSV) with 10 CFR Part 50, Appendix R, concerning fire protection programs for nuclear power facilities. This evaluation discusses both the proposed safe shutdown systems and the exemptions requested.

1.1 Safe Shutdown Systems A review of the safe shutdown systems, proposed by Public Service Company of Colorado (PSC) for FSV fire protection considerations, was undertaken by Region IV personnel, in accordance with TIA 83-105, in October 1985.

The initial review of the PSC proposal (Reference 1) resulted in a u

number of questions which were transmitted to PSC by NRC letter dated

. November 1, 1985 (Reference 3). PSC responded to these questions in their December 20, 1985 letter (Reference 4) which deferred the submittal of an analysis to justify the effectiveness of the proposed forced circulation cooldown models and the submittal of the fire protection program, until the fourth quarter of 1986.

Review of the December 20, 1985 response resulted in a number of followup and clarification questions which were discussed during a telephone conference on February 26, 1986, and documented in PSC letters dated March 14 and April 4, 1986 (References 5 and 6 respectively).

1.2 Exemption Requests By letter dated April 1,1985 (Reference 1), the licensee submitted Appendix R Re-evaluation Report No. 4, which contained exemption requests and proposed fire protection and systems-related modifications. Eleven exemptions from the technical requirements of Section III.G and one exemption from Section III.J. of Apperidix R to 10 CFR 50 were requested.

By letter dated May 31, 1985 (Reference 2), the licensee submitted Report No. 5. "A Comparison and Evaluation of Fort St. Vrain Building No. 10 to BTP 9.5-1, Appendix A."

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. Section III.G.2 of Appendix R requires that one train of cables and equipment necessary to achieve and maintain safe shutdown be maintained free of fire damage by one of the following means:

a. Separation of cables and equipment and associated non-safety circuits of redundant trains by a fire barrier having a 3-hour rating. Structural steel forming a part of or supporting such fire barriers shall be protected to provide fire resistance equivalent to that required of the barrier;

b. Separation of cables and equipment and associated non-safety circuits of redundant trains by a horizontal distance of more than 20 feet with no intervening combustibles or fire hazards. In addition, fire detectors and an automatic fire suppression system shall be installed in the fire area; and

c. Enclosure of cables and equipment and associated non-safety circuits of one redundant train in a fire barrier having a 1-hour rating. In addition, fire detectors and an automatic fire suppression system shall be installed in the fire area.

l If these' conditions are not met,Section III.G.3 requires an i alternative shutdown capability independent of the fire area of j concern. It also requires that a fixed suppression system be installed in the fire area of concern if it contains a large l

concentration of cables or other combustibles. These alternative requirements are"not deemed to be equivalent; however, they provide

. equivalent protection for those configurations in which they are v' accepted.

Because it is not possible to predict the specific conditions under l which fires may occur and propagate, the design basis protective

! features are specified in the rule rather than the design basis fire.

Plant specific features may require protection different than 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 j the technical requirements of Section III.G of Appendix R.

! In sumary,Section III.G is related to fire protection features for i ensuring that systems and associated circuits used to achieve and maintain safe shutdown are free of fire damage. Fire protection configurations must either meet the specific requirements of Section III.G or an alternative fire protection configuration must be

.iustified by a fire hazard analysis.

l Our general criteria for accepting an alternative fire protection i configuration are the following:

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a The alternative assures that one train of equipment necessary to achieve hot shutdown from either the control room or emergency control stations is free of fire damage.

The alternative assures that fire damage to at least one train of equipment necessary to achieve cold shutdown is limited such that it can be repaired within a reasonable time (mincr repairs with components stored on-site).

Modifications required to meet Section III.G would not enhance fire protection safety above that provided by either existing or proposed alternatives.

Modifications required to meet Section III.G would be detrimental to overall facility safety.

C 2.0 Evaluation 2.1 Safe Shutdown Systems The evaluation of the safe shutdown system models was based on the Appendix R-Fire Protection Regulatory Guidance contained in PSC's August 17, 1984 letter. This letter is included as Appendix A to Peport No. 1 (see Reference la) and reflects the guidance provided by ,

the NRC staff for fires in congested cable areas and noncongested cable areas.

It was noted (see Figures 4.4 through 4.18 of Reference Ic) that some u- electrical cables for Train A and Train B components are located in close proximity in the same fire area (s). The licensee is rerouting some of these cables to improve separation, and it is expected that the adequacy of electrical separation will be verified during NRC inspections, after modifications are complete.

2.1.1 Congested Cable Areas The criteria delineated in the regulatory guidance for fires in congested cable areas was based on the use of the Alternate Cooling Method (ACM).

(The congested cable areas are defined as the Control Room, 480 Volt Switchgear Room, the Auxiliary Electric Room, and the congested cable area along the "G" and "1" walls.)

The ACM is an independent, diesel-driven, 2500 KW electrical generator with an associated distribution system that is used to provide power to selected plant components through manual transfer switches. The ACM can be placed in operation in approximately 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and provides a source of ThePrestressed procedure used Concrete to placeReactor the ACMVessel in operation (PCRV) (S0PLiner 48-01Cooling).

is included Water (LCW as Appendix B to Reference la.

The NRC approval of the ACM is contained in the Safety Evaluations attached to License Amendments 14, 18, and 21 (References 7, 8, and 9).

Since the licensee states (see References 4 and 5; Item 6.b) that "the design, loads and intent of the ACM has not been modified significantly since its use was approved," no additional review or approval was required.

2.1.2 Noncongested Cable Areas The criteria delineated in the regulatory guidance for fires in noncongested cable areas were based on the requirements contained in

_ Section III.L. of Appendix R to 10 CFR Part 50. The limiting consequences require that, "For any single fire in a non-congested cable area, means shall be available to shut down and cool down the reactor in a manner such that no fuel damage occurs (i.e. maximum fuel particle temperature does not exceed 2900 degrees F). There shall be %

simultaneous rupture of both a primary coolant boundary and the associated secondary containment boundary such that no unmonitored radiological releases of primary coolant occur."

The means proposed by PSC in Reference la, to shut down and cool down the reactor, consist of two Trains (A and B) of Safe Shutdown Systems which provide for reactivity control, PCRV integrity, and decay heat j removal.

2.1.2.1 Reactivity Control

,- Reactor shutdown is accomplished by insertion of the 37 control rod pairs via a manually or automatically initiated reactor scram. A scram is accomplished by interrupting the power supply to the Control Rod Drive Mechanisms (CRDM) and their associated holding brakes which allows the control rods to fall by gravity into the core. Two Wide Range Nuclear Instruments (one per Train) are utilized to monitor the core reactivity.

In addition, the FSV design includes a Reserve Shutdown System which can be manually actuated to insert separate neutron absorbing material into the core for reactivity control.

Since, (1) there is a high degree of assurance that sufficient neutron absorbing material can be inserted to make the reactor subcritical, (2) there will be little effect on core reactivity except for temperature changes, and (3) there are adequate provisions for monitoring the core reactivity, we find the reactivity control provisions to be acceptable.

2.1.2.2 PCRV Integrity .

The shutdown models made the assumption that the integrity of the PCRV would be assured by maintaining the decay heat removal function. PSC subsequently provided (in Reference 4) the results of a study which found that "the absence of liner cooling had no significant effect on maximum fuel or orifice valve temperatures."

• In addition to maintaining the structural integrity of the PCRV, the integrity of the various PCRV penetrations must also be maintained to control the primary coolant inventory. The majority of the penetrations are through the top head of the PCRV. These consist of 37 CRDM and purification system penetrations. Steam generator and helium circula-tor penetrations are located in the bottom head and the safety valves and instruments penetrate the sidewalls. All penetrations have a double closure design and are relatively unaffected by fires from a loss of integrity viewpoint. A summary of the PSC evaluations is contained in Reference la, Section 2.1.

Based on the results of the above study and the ability to provide liner cooling water via the ACM as discussed in Section 2.1, we find the PCRV integrity provisions to be acceptable.

2.1.2.3 Decay Heat Removal (DHR)

The shutdown model for DHR proposed in Reference la consists of two trains of components which previde for core heat removal, primary coolant inventory control, process monitoring, and secondary heat removal.,

a. Core Heat Removal The core heat removal model contains the following flow paths:

Train A - Condensate Pump 1C provides condensate flow from the DHR Exchanger through a steam generator and a helium circulator and

• back through the DHR Exchanger.

Train 8 - The diesel driven fire water pump provides flow from the main cooling tower through a steam generator and a helium circulator and back to the main cooling tower via the condensate tank and service water return sump.

These flow paths are shown schematically in Figures 2.1-8 and 2.1-9 in Reference la; copies of which are included in this evaluation as Attachments I and 2. A discussion of various aspects of these flow paths is contained in the following paragraphs.

1) The electrical power supplies utilized are the ACM diesel generator (DG) for Train A components and Emergency Diesel Generator (EDG) set B for Train B components. The use of the 4 ACM DG was necessitated by the lack of sufficient separation between the A and B EDG clectrical cables. The proposed ACM DG electrical flow path runs from the 4160 volt ACM bus to the HVAC switchgear bas, to its feeder supply at the Reserve Auxiliary Transformer, through the feeder to the 4160 volt switchgear Bus 2 where it can be cross-connected to either Bus 1 or 3. The 4160 volt busses provide power to their associated, essential, 480 volt busses (1, 2, and 3). The

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, EDGs provide power directly to the associated 480 volt essential bus; EDG A to Bus 1, EDG B to Bus 3. (These flow paths can be seen on Figure 8.2-5 of the FSV FSAR.)

The proposed means to provide electrical power are acceptable.

The adequacy of procedures, testing and training will be verified during routine inspection activities.

2) The effectiveness of the flow paths through the steam generators in the proposed models was questioned in Reference 3; the requested analysis has not, as yet, been completed.

However, based on a review of the available information, the conceptual designs of the flow paths are acceptable provided:

(a) the above analysis verifies the effectiveness of the flow path, and (b) sufficient makeup water capability is demonstrated.

As stated in Reference 12, analyses are exploring various flow path options.

3) The design of both Train A and B includes the use of the DHR Exchanger to transfer the heat retroyed from the primary coolant in the steam generator to the service water system. A discussion of the service water system is contained in a subsequent subparagraph (d) on secondary heat removal.

4) Both shutdown tooling trains provide for the operation of one Helium Circulator to transport the heat in the reactor core to the steam geaerators; Train A utilizes condensate flow

. directly, Train B utilizes fire water through the water booster pump to drive the circulator's water turbine. A review of FSAR Section 14.4.2.1, indicates that " Ore helium circulator can provide nearly 4.5% of rated flow through the reactor core when operated by itself with condensate water supplied to this water-turbine drive." Based on this

• information, the primary flow requirement can be met.

The water used to drive the water turbine of the circulators discharges into the Turbine Water Drain Tank where it is removed by one of two Turbine Water Removal Pumps. The tank is common to both trains and the pumps are located approximately 5 feet apart, therefore, adequate separation is not maintained. However, the licensee has proposed to compensate for potential fire damage to both pumps by implementing a repair procedure using a portable turbine water removal pump and casualty cable. The adequacy of this i procedure will be verified during future staff inspections.

A review of the ability to operate the circulators with the proposed auxiliary equipment (see Attachment 3 for flow

. diagram) disclosed provisions for providing bearing water but not for providing a source of the buffer helium for shaft sealing. The PSC response (Reference 4, Item 8) addressing the acceptability of operating a circulator without buffer helium indicates that tests which were conducted showed that there would be little effect on either helium egress or water ingress. Therefore, the bearing water system is acequate.

The makeup source to the bearing water system is from the condensate tanks via the Emergency Bearing Water Makeup Pump for Train A and the nonnal Bearing Water Makeup Pump for Train B, both of which can be cross connected. While the makeup systems appear to be acceptable, the power supply cables lack the required separation. The licensee proposed modifications which will result in greater physical separation of the cables. These modifications have been reviewed and found acceptible as discussed in our evaluation of the exem tion request for the Reactor Building (See Section 2.9 .

b. Primary Coolant Inventory Control Primary coolant inventory is centrolled by maintaining PCRV integrity. A discussion of PCRV integrity is contained in Section 2.1.2.2, above,

c. Process Moni'toring a' The process monitoring function is required to confirm PCRV e integrity, core heat removal and secondary heat removal.

1) PCRV Integrity Monitoring PCRV integrity can be monitored by the use of primary coolant pressure and temperature indications, if available. PSC has, however, requested an exemption from monitoring PCRV integrity in their request for exemption from the requirements contained in Section III.G.2. of Appendix R for the reactor building. The basis for this exemption request is adequate.

2) Core Heat Removal and Secondary Heat Removal Monitoring Core heat removal monitoring is proposed to be accomplished by monitoring primary coolant flow in conjunction with cecondary heat removal monitoring (i.e., etes= generator ficw and exit temperature). Coolant flow is detected by <

monitoring the differential pressure across the circulator; the secondary heat removal is detected by monitoring

feedwater flow and steam generator exit temperature. When questioned on the adequacy of this design PSC responded (Referenc? 4, Item 15) that if primary flow could be confirmed, heat would be transferred to the helium as it passed through the core, and that monitoring steam generator flow and temperature would verify decay heat removal. It should be noted that the feedwater flow instruments have a range of 0-400,000 lbs./hr. and the condensate flow available would be less that 1% of the range; this would mal.e accurate flow measurement difficult.

To adequately monitor heat removal, it may be necessary to monitor a temperature diffet ential (i.e., inlet and outlet temperatures) rather than the proposal to only monitor the

, steam generator exit for constant or decreasing temperature.

In addition, the circulator flow instruments lack the required separation and are included in the reactor building exemption request. The adequacy of the proposed instrumentation has been addressed in the exemption request evaluation (see Section 2.9).

d. Secondary Heat Removal As discussed above, secondary heat removal is accomplished through the use of the DHR Cxchanger where the decay heat, which was transferred to the feedwater in the steam generators, is

,. transferred to the service water system. The service water models are shown schematically in Figures 2.1-11A and 2.1-11B of Reference la. These figures are included as Attachments 4 and 5.

1) The Train A service water (SW) system utilizes a SW pump to provide flow from the SW cooling tower through the SW

! strainer to the various system cooled components or " loads."

The return path from these loads is back to the SW cooling tower where one of the SW cooling tower fans is operated to reject the heat to the atmosphere. Makeup flow to the SW cooling tower is provided from the settling ponds by a circulating water makeup pump. The SW pump, the tower fan and the makeup pump can all be powered from the ACM DG.

2) The Train B SW system utilizes a circulating water pump to provide flow from the Main Cooling Tower to the SW systen, through the various loads, and back to the tower. The licensee's evaluation of the need for operating a Main Cooling Tower Fan is contained in Reference 4. Item 5. This evaluation concludes either (a) makeup may be that if cooling) added or (b aassistance fan may be is desired, operated.

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3) PSC provided a discussion of single failure considerations for components cocinon to both proposed trains of SW in Reference

4. Item 1. In particular, the SW strainer and the flow control valves to the various loads were adcressed. Since these components are water-filled mechanisms which can be manually operated, their use was determined to be acceptable.

2.1.3 Implementation of Safe Shutdown Models The ability to physically implement the required flow paths for the

.i safe shutdown trains discussed in the preceding section was also evaluated. This evaluation considered whether the flow paths were

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physically practical and if the flow paths could be esthblished within the required time period.

2.1.3.1 Establishing Flow Paths

. A review of numerous facility piping drawings (P& ids) showed that the

proposed flow paths were possible but that numerous interconnections

! and alignments would be necessary. The licensee's response (Reference 4, Item 2b) to questioning on why all valves necessary to complete the flow path were not included in the listings provided in Reference la, stated that only those manual valves whose positions are required to be changed were listed. Further PSC reviews did identify some additional manual valves which were added to the listings. (All power operated valves are checked whether required to change position or not.) The 4

plant procedures do not require a check of valve positions on a routine basis but only when returning a system to operation following an outage.

.,. A further discussion of the PSC position, contaired in Reference 10,

states that the existing controls are adequate and that centrols over 1

non-Technical Specification systems / components will be incorporated in the Fire Protection Program. The acceptability of the valve lineup surveillance will be evaluated during an NRC inspection, i'

The description of the " testing program to be implemented to verify the operability of the proposed safe shutdown models," requested in Reference 3, has not been received. The discussions contained in References 4

. and 5 (Item 11) do not appear to indicate that any integrated systems testing or physical walkdowns are planned. Whether or not adequate testing and adequate walkdowns have been performed will also be determined during an NRC inspection.

2.1.3.2 Manual Actions and Timing A concern was raised, in Reference 3, that the numerous manual actions required to implement the shutdown models may require more manpower than would be available. The PSC response contained in Reference 4, Items 12 and 13, concluded that all required manual actions could be accomplished within the required time limit of 90

minutes by the nine personnel required to be on shift. The response stated that although five personnel are dedicated to the Fire Brigade, the remaining four, operating independently for 85 minutes, could implement the shutdown model. It was noted that all actions were assumed to be mutually independent and that no supervision nor control room monitoring had been considered. PSC agreed to perform a more realistic assessment of the manpower requirements in Reference 5. PSC has now made provision for ten personnel on shift ar.d has made an assessment of the manning required tc accomplish required manual actions for each fire area (Reference 11). This includes contrcl room manning. Subject to confirmation through NRC inspection efforts that procedures and training are adequate, we conclude that the proposed staffing level is acceptable.

2.2 Exemption Request for Three Room Complex and Diesel Generator Rooms 2.2.1 Exemption Requested The licensee requested exemptions from the technical requirements of Section III.G.2 of Appendix R to 10 CFR 50 in these areas to the extent that it requires that openings in 3-hour rated fire barriers be protected with similarly rated fire dampers, doors, and penetration seals.

2.2.1.1 Discussion (Three Room Complex)

The Control Room Complex has been considered as a single fire area.

The Control Complex houses the 480 volt switchgear room, the auxiliary

,- electrical equipment, battery rooms, and the control room. The perimeter walls are constructed of reinforced concrete and have a 3-hour fire rating. They have unrated dampers where HVAC ducts penetrate the walls. The dampers are designed to close automatically when the Halon fire suppression system actuates. Doors in the Control Complex boundary fire walls were originally UL-labeled, 3-hour fire door assemblies; however, hardware has been changed and security modifications made. As a result, these doors are not now considered 3-hour fire doors. The penetration openings in the Control Complex walls are sealed with both fire-rated and unrated penetration seals.

The Control Complex walls feature some steel columns which are

, partially embedded within the walls. The exposed steel is unprotected inside the lower two rooms of the Control Complex proper. The steel columns in the control room itself are enclosed by concrete blocks.

3 The steel columns are not an integral part of the concrete wall from i the standpoint of structural integrity or fire rating but are used for control complex floor connections.

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Existing fire protection consists of halon and water sprif fire '[ '

suppression systems in the 480V switchgear and electrical-equipmece rooms; a halon fire suppression system in the control room;th partial-fire detection system in the control room and area-wide fire ditection systems in the rest of the Three Room Complex; and portable-fire.

extinguishers and manual hose ~ stations. In, addition, automatic water spray systems exist along the "G" and "J" walls outside of the.Three Room Complex. In Appendix R Re-evaluation Report No. 4, the licensee committed to repair the doors in the west wall-of the , control complex <

and to upgrade the seals in the west wall to be'3-hour fire-rated. - -

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2.2.1.2 Discussion (Diesel Generator Rooms) f' The diesel generator rooms are considered as two separate fire areas.

They are bounded by reinforced concrete walls and ceiling having a fire resistance rating of at least 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />., Several unrated dampers exist in the HVAC duct penetrations of these walls whsre they form a comon boundary with the Turbine Building:iThe dampers'were installed in conjunction with the existing carbon dioiide fire suppression system for each room and are designed to close when the system actuates. No unprotected penetrations exist'in the'comon wall between the diesel generators. Existing fire' protection. includes fire detection systems, the above-referenced automatic fire duppression systems, portable fire extinguishers, and manual hose statfons.~

The licensee justifies the exemptions in these areas on the basef of

• the existing fire' protection, the proposed modificatioid, and tne -

. ability to safely shut down the plant in the event of a fire.

,- w 2.2.3 Evaluation ..

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The technical requirements of Section III.G are not' met in these locations because the penetrations of the 3-hour fire barriefs are'not '

i all protected by doors, dampers or penetration seals that,have a s 3-hour fire rating. In addition, there exists some unprotected stcel .

in the perimeter walls of the Three Room Complex. ,

We were concerned that in the event of a fire of significant

! magnitude, products of combustion would pat,s through the wall and . '

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damage redundant / alternate shutdown systems on the other side. ,

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However, the areas on both sides of these walls are protected by automatic fire detection systems as described in the Appendix R Evaluation Report. These systems alarm in the Control Room. We therefore cxpect that any potential fire would be detected in its incipient stages before significant flame spuad or room tnscerature rise occurred. The plant fire brigade would then be dispaM hed and..

would put out the fire using manual fire fighting equipment:

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'4 If rapid fire spread occurred, the automatic fire suppression systems i would actuate to control the fire and reduce ambient temperature rise. Until this occurred, the existing walls which surround these 4 areas would act to confine the effects of the fire to the area of

- origin.

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/ Because openings exist in the walls, we expect a quantity of smoke and hot gases to pass through them and enter the adjoining locations. But the smoke would be so dissipated and the hot gases cooled to the point

. where, in our judgement, they would not represent a significant threat to shutdown-related systems outside of the fire area.

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' Based on our evaluation, we conclude that the licensee's alternate

, /' fire protection configuration, with the proposed modifications, will achieve an acceptable level of fire safety equivalent to that provided by Section III.G.2. Therefore, the licensee's reauest for exemption for a complete 3-hour fire barrier in the Three Room Complex and Diesel Generator Rooms should be granted.

2.3' ExempkionRequestforControlRoom 2.'3.1 Exemption Requested j The licensee requested an exemption from the technical requirements of Section III.C.3 of Appendix R to 10 CFR 50 to the extent that it r., , requires that a fire detection system be installed throughout a fire

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area that has been provided with an alternate shutdown capability.

I.3.2 Discussion The Control Room is a separate room within the Three Room Complex. It

'is bounded by walls that have a 3-hour fire rating, except for the doors, dampers, and penetration seals which are evaluated in Section 2.2.

4 The principal fire hazard within the area consists of cable insulation l /' and paper. Existing fire protection includes an area-wide halon fire suppression system, fire detectors in the control room cabinets and l' , consoles, portable fire extinguishers, and manual hose stations.

The licensee justifies the exemption on the basis of the existing

- protection, the continuous presence of control room operators, and the i ability to safely shutdown the plant independent of the Three Room Complex.

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2.3.3 Evaluation i . The tech'nical reoufrements of Section III.G are not met in this location because of the absence of a fire detection system that j ','

- provides area-wide coverage.

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,We were concersed that because of the absence of an area-wide fire detection system, a fire could develop which would damage shutdown 6

systems to the extent that the plant could not be safely shut down.

However, the control room is continuously manned and automatic smoke s

detectors are located in the control room cabinets and consoles. We, therefore, have reasonable assurance that a fire would be detected and

, suppressed by the control room operators or the plant fire brigade

( early, before significant damage occurred.

If a serious fire developed, the existing halon fire suppression

, system would actuate to put out the fire or control it until the plant fire brigade arrived.

If such a fire caused the loss of redundant shutdown' systems, the Alternate Cooling Method is available to bring the plant to a safe shutdown condition. This ACM capability is physically and electrically independent of the Three Room Complex. Therefore, an area-wide fire detection system in the Control Room is not necessary to provide us with reasonable assurance that a fire would be detected and safe shutdown capability maintained free of fire damage.

2.3.4 Concluhion '

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i Based on our evaluation, we conclude that the licensee's alternate

.i fire protection configuration provides an acceptable level of fire

• safety equivalent tc< that provided by Section IIf.G.3. Therefore, the licensee's request for exemption for an area-wide fire detection in

, the Control Room should be granted.

, 2.4 Exemption Request for Turbine Building 2.4.1 Exemption Requested y The' licensee requested an exemption from the Technical requirements of p'

Section III.G.2 of Appendix R to 10 CFR 50 to the extent that it requires that a fire detection system be provided throughout a fire area.

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2.4.2 Discussion

, 8 i The Turbine Building houses the secondary plant equipment including

! such components and systems as the turbine generators; main condenser; l steam, condensate, and feedisystems; HVAC systems; and the emergency

water booster pumps.

l The building is essentially a three-level structure, except for the access controb bay portion. It is constructed of insulated dual corrugated steel walls'and a metal deck-type roof.

The principal fire hazards in the ' building consist of accumulations of l 1ube oil, hydraulic oil, hydrogen gas, and cable insulation. However,

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the locations which contain these hazards are separated from the rest of the building by 3-hour fire-rated walls, are protected by automatic fire suppression systems, or both.

i Existing fire protection includes partial fire detection and fire suppression systems, as discussed in Appendix R Evaluation Report No. >

4, manual hose stations, and portable fire extinguishers. In Report No. 4, the licensee committed to modify and extend the existing fire detection system to provide area-wide coverage except for the turbine generator operating floor and the upper level of the Access Control Bay. The fire detection system will be in accordance with the provisions of National Fire Protection Association Standard No. 72E.

The licensee justifies this exemption on the basis of the existing fire protection, the proposed modifications, and the fact that there are no shutdown-related systems in those locations where no fire detectors will be provided.

2.4.3 Evaluation The technical requirements of Section III.G.2 are not met in this location because redundant, shutdown-related systems are not separated by more than 20 feet, free of intervening combustibles. In addition, i automatic fire suppression and detection systems are not provided

throughout this area. Our evaluation of the separation and fire suppression issues is contained in Sections 2.5 and 2.10 of this report.

, Our principle concern with this exemption was that because of the u- absence of an area-wide fire detection system, a fire of significant

, magnitude could develop and damage systems needed to safely shutdown the plant. However, a fire detection system that meets the requirements of NFPA 5tandard No. U will be installed throughout every elevation of this fire area that does contain shutdown-related systems. If a fire should occur in these locations, we expect it to be detected by the system. An alarm would be transmitted automatically to the Control Room and the fire brigade would subsequently be dispatched. The brigade would put out the fire using manual fire fighting equipment.

If fire should break out on the operating floor or the upper elevations of the Access Control Bay, we expect it to be discovered, after some time delay, by plant operators or the security force. Until the arrival of the fire brigade, there are no shutdown systems that could be damaged by fire l in these locations. Therefor.e an area-wide fire detection system is not

necessary to provide us with reasonable assurance that a safe shutdown l

capability will remain free of fire damage.

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• l 2.4.4 Conclusion l

l Based on our evaluation, we conclude that the licensee's alternate fire protection configuration, with the proposed modifications, will I

! s achieve an acceptable ~ level of fire safety, equivalent to that provided by Section III.G.2. Therefore, the licensee's request for exemption for an crea-wide fire detection system in the Turbine Building should be granted.

2.5 Exemption Request for Access Control Bay 2.5.1 Exemption Requested The licensee requested an exemption from the technical requirements of Section III.G.2 to the extent that it requires that radundant shutdown-related systems be separated by 20 feet free of intervening combustible materials or by a 1-hour fire barrier and the area protected

_ by an automatic fire suppression system and a fire detection system. .

2.5.2 Discussion The Access Control Bay is a multi-level structure which is part of the larger Turbine Building Fire Area. It extends upward from elevation 4846 ft., 6 inches to the roof at elevation 4928 ft., O inches. Three reinforced concrete floors and one partial steel grating floor further subdivide the Access Control Bay above elevation 4846 ft., 6 inches.

Within this structure, the licensee has identified redundant reactor plant exhaust fans, on elevation 4846 ft., 6 inches, that are not protected per the requirements of Section III.G. The fans are separated from each other by about 18 feet, with no intervening combustibles.

The fire hazard in the Access Control Bay consists of charcoal, lubricating oil, and cable insulation which represents a fire load of u- abmt 20,750 BTU /sq. ft. This quantity of combusticles, if totally consamed, would produce an equivalent fire severity of about 16 minutes as determined by the ASTM E-119 time temperature curve.

Existing fire protection includes manual hose stations and portable fire extinguishers. In Appendix R Compliance Report No. 4, the licensee committed to install an automatic fire detection system on elevation 4846 ft., 6 inches of the Access Control Bay. The system will be in accordance with the provisions of NFPA Standard No. 72E.

l In addition, the licensee proposed to relocate cables and transfer switches to the A-train fan so as to be located at least 35 feet away from its redundant counterpart.

The licensee justified this exemption on the basis of the existing fire protection, and the proposed modifications. In addition, the l licensee indicated that in the event that these fans were damaged by a fire, alternate cooling is available through a chiller unit and recirculation fan that are located in another fire area.

2.5.3 Evaluation l

Although the licensee requested an exemption from Section III.G.2, the requirements of Section III.G.3 apply because of the availability of l

l

the alternative cocling capability. The requirements of Section III.G.3 are not met in the Access Control Bay because of the absence of an area-wide fixed fire suppression system.

Our principal concern with the level of fire safety in this location was that because of the relative proximity of the reactor plant exhaust fans, a fire of significant magnitude would damage redundant shutdown-related systems to such an extent that safe shutdown could not be achieved and maintained.

However, the fire load in this location is not significant, with combustible materials dispersed throughout the elevation. If a fire should occur, it would be detected by the fire detection system in its incipient stages before significant flame propagation or room temperature rise occurred. The alarm would be automatically transmitted to the control room. The fire brigade would then be dispatched and would put out the fire using manual fire fighting equipment. Pending arrival of the brigade, the effects of the fire would be mitigated because the smoke and hot gases would rise up into the high ceiling area, which would tend to act as a heat sink. Also, the fan motors and related cabics would be shielded from the effects of a fire by the metal fan enclosures. Nevertheless, if a fire did result in damage to both reactor plant exhaust fans, the licensee will be able to recover from this damage by relying upon a chiller unit and recirculation fan that is located in a separate fire area. Therefore, the absence of a fixed fire suppression system is not necessary to provide us with reasonable assura~nce that safe shutdown can be achieved and maintained.

u- 2.5.4 Conclusion Based on our evaluation, we conclude that the licensee's alternate fire protection configuration, plus the proposed modifications, will achieve an acceptable level of fire protection equivaler.t to that provided by Section III.G. Therefore, an exemption for the absence of a fixed fire suppression system in the Access Centrol Bay should be granted.

2.6 Exemption Recuests for Outside Areas-Exterior Routing and Turbine /

Reactor Builcings-Common Wall 2.6.1 Exemption Requested The licensee requested an exemption from the technical requirements of Section III.G.2 of Appendix R to 10 CFR 50 in these locations to the extent that it requires a 3-hour fire barrier to separate redundant / alternate shutdown related systems in separate fire areas.

2.6.2.1 Discussion (Outside Areas-Exterior Routing)

The Alternate Cooling Method (ACM) diesel and certain ACM related components are relied upon as the emergency power source for fire

: J protection shutdown Train A. The ACM diesel, transformers, plant 4kV switchgear, 4kV HVAC switchgear, 4160-480 volt transformers, reserve auxiliary transformer bus, and ACM 4kV switchgear are located outside of the Turbine Building. There is also ACM equipment located in the Evaporative Cooler Building, east of the Turbine Building near its southeast corner. ACM equipment in this building are the ACM batteries, ACM-MCC, and ACM-480V load center.

The Turbine Building contains the emergency diesel designated as the emergency power supply for the B shutdown train. Cabling %nd components associated with the B shutdown train are located within the Turbine Building.

Cabling from the ACM diesel feeding the 4kV switchgear, and then routed to the 4160/480 volt transformers, is used as the emergency backfeed to load centers in the Three Room Control Complex to serve as the power supply for fire protection shutdown Train A. The cable routings up to the 4160-480 volt transformers are routed underground, with the exception of overhead bus duct feeds between the 4kV HVAC switchgear, reserve auxiliary transformer, and the plant 4kV switchgear.

Feeds from the transformers into the three-room complex are open ventilated bus ducts routed above ground. These feeds pass along the east side of the Turbine Building wall.

The 4kV switchgear is located south of the Turbine Building in the vicinity of the diesel generator rooms. The south wall of the diesel generator rooms is reinforced concrete construction. The 4kV switchgear is located inside a separate metal enclosure that is accessed from the yard area. The 4kV switchgear enclosure is located

, approximately 8 feet south of the Turbine Building with open space l in-between. Cabling within the 4kV switchgear enclosure enters from

underground.

The reserve auxiliary transformer bus duct is also used as part of this

! ACM backfeed. The reserve auxiliary transformer is located outside approximately 20 feet from the Turbine Building. The closest Train B shutdown component is the Train B emergency diesel generator. The emergency diesel generator room is a separate fire area, and is separated from the outside by a reinforced concrete wall.

An HVAC switchgear enclosure associated with ACM is also located south of the Turbine Building, approximately 15 feet from the building; but over 30 feet from the nearest fire protection shutdown components within the Turbine Building.

t ACM components in the Evaporative Cooler Building are used as part of I fire protection shutdown Train A. The Evaporative Cooler Building is a separate fire area, since it is a separate building with exterior walls to the outside. This building is separated from the Turbine Building by approximately 10 feet of open space, free of intervening combustibles.

l

. Other components in the yard area associated with the ACM, when used for the Train A emergency power supply, are the ACM diesel, ACM transformer, and the ACM 4kV switchgear. These structures are located greater than 100 feet east of the Turbine Building.

2.6.2.2 Discussion (Turbine / Reactor Buildings-Common Wall)

The Turbine Building and Reactor Building are considered as two separate fire areas. The common wall between these two arers is constructed of corrugated steel. All openirgs in this wall are sealed so as to maintain the pressure differential required for the Reactor Building. Redundant shutdown-related equipment that is located on

- both sides of the wall are separated by at least 35 feet. Existing fire protection includes fire detection and fire suppression systems as described in Appendix R Evaluation Report No. 4, manual hose stations, and portable fire extinguishers.

The licensee justifies the exemptions on the existing fire protection, the spatial separation between shutdown-related systems, and the ability of the non-rated walls to provide a degree of passive fire protection until any potential fire is extinguished.

2.6.3 Evaluation The technical requirements of Section III.G.2 and 3'are not met in these locations because normal shutdcwn systems are not separated from their redundant counterparts or the systems associated with the l

alternate cooling method by a 3-hour fire-rated barrier.

l Our principal concern was that a fire of significant magnitude may result in damage to components associated with the nomal shutdown systems and the alternate cooling method.

l If a fire vere to occur in the above-referenced outside locations, a l potential exists for components associated with the ACM to be damaged.

l However, because these areas are located outside and away from the normal shutdown systems located within the Turbine Building, we do not expect the products of combustion or radiant energy from such a fire to affect the normal systems. Smoke and hot gases would tend to be dissipated in the open air. Radiant energy would be mitigated by the intervening open space and by the exterior walls of the Turbine Building.

Similarly, if a fire were to occur inside the Turbine or Reactor t Buildings, we expect the fire to be detected by the automatic fire

- detection systems or by plant operators or the security force. The I fire would either be extinguished manually by the plant fire brigade or by the automatic fire suppression systems. Because these locations are large open plant areas, the smoke and hot gases from such a fire might spread within each area. But it is our judgment that the metal and masonry walls which bou,nd these fire areas are capable to a

significant extent of confining the effects of the fire to the immediate fire area, until the fire is extinguished. Because these walls are not all fire-rated, some products of combustion may spread beyond them. However, the smoke and hot gases would be cooled and dissipated so that there will be no threat to the redundant / alternate shutdown systems in the adjoining fire areas. Therefore, complete 3-hour fire-rated walls are not necessary to provide us with reasonable assurance that safe shutdown conditions could be achieved and maintained with undamaged systems in the other five areas.

2.6.4 Conclusion Based on our evaluation, we conclude that the licensee's alternate fire protection configuration will achieve an acceptable level of fire safety, equivalent to that achieved by compliance with Section III.G.2 and III.G.3. Therefore, the licensee's request for exemption for a 3-hour fire wall between the Turbine Building and the Reactor Building and outside areas should be granted.

2.7 Exemption Requests for Alternate Cooling Method / Congested Cable Area Interface 2.7.1 Exemption Requested The licensee requested an exemption from the technical requirements of

Section III.G.2 of Appendix R to 10 CFR 50 to the extent it requires that redundant shutdown-related systems be separated by more than 20

, feet free of intervening combustibles and the area protected by '

u- automatic fire detection and suppression systems.

2.7.2 Discussion Cabling associated with forced circulation cooldown components passes through the congested cable areas (CCA) outside of the "J" and "G" walls for the three room complex and then into the three room ccmplex.

For a fire at these locations, safe shutdown would be achieved using j systems associated with the ACM. In general, ACM components and cabling l are located in other fire areas outside of the Reactor and Turbine l Buildings. Most of the cables and components for the ACM that are located in the Reactor and Turbine Buildings are located more than 40 feet away from the congested cable area. For those systems that are l located less than 40 feet from the CCA, described in Appendix R Compliance Report No. 4, the licensee has identified other systems that could be employed to achieve safe shutdown, a

The principal fire hazard in these ACM/CCA interface areas is cable l insulation. However, the areas of concentrated quantities of cables j are protected by automatic sprinkler systems. In addition, these i

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locations are protected by fire detection systems and are provided with portable fire extinguishers and manual hose stations.

The license justified this exemption on the existing fire protection, the spatial separation between shutdown systems, and the availability of a number of systems that could be relied upon to achieve and maintain safe shutdown.

2.7.3 Evaluation The technical requirements of Section III.G are not met in these locations because the alternate shutdown capability is not physically and electrically independent of the fire area.

Our principal concern with the level of fire safety in these locations was that a fire of significant magnitude might damage systems associated with both the manual shutdown capability and the alternate cooling method. There is no major unmitigated fire hazard in these l locations. The only significant hazard which would represent a threat to shutdown systems is the concentration of combustible insulation on the cables. However, these cable concentration areas are protected by automatic sprinkler systems. The suppression systems along the "G" and "J" walls were originally designed for manual actuation. However, at our request, the licensee converted these systems to automatic actuation. We acknowledged that this conversion would not completely conform to the guidelines of NFPA Standards 13 and 15. But, it was our judgement that ari automatic system would achieve a higher level of protection.

. The interface areas will be protected by an automatic fire detection system that meets the requirements of NFPA Standard No. 72E. As a result, we expect any potential fire to be detected early, before l significant fire propagation or room temperature rise occurs. The j fire would then be extinguished by the plant fire brigade using manual

! fire fighting equipment. If rapid fire spread occurred, we expect the l automatic wet pipe sprinkler systems to actuate and limit fire spread, moderate room temperature rise, and protect the shutdown-related cables along the "G" and "J" walls. Until the arrival of the brigade, the spatial separation between shutdown systems provides passive protection to prevent damage to redundant / alternate shutdown systems.

For those systems which are not sufficiently separated, the licensee has identified alternate means of achieving and maintaining safe shutdown that would not be affected by a fire.

. 2.7.4 Conclusion l

Based on our evaluation, we conclude that the licensee's alternate fire protection configuration, with proposed modifications, will achieve an acceptable level of fire safety equivalent to that achieved by compliance with Section III.G. Therefore, the licensee's

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request for exemption in the ACM/CCA Interface Areas should be granted.

2.8 Exemption Request for Emergency Lighting 2.8.1 Exemption Requested The licensee requested an exemption from the technical requirements of Section III.J of Appendix R to 10 CFR 50 to the extent that it requires emergency lights to be powered by individual 8-hour battery packs.

2.8.2 Discussion The plant is presently equipped with hard-wired, essential / emergency

- back-up lighting systems powered from the standby diesel generators and the plant DC system. However, these systems are not sufficiently independent such that they would be available in the event of a fire.

In Appendix R Compliance Report No. 4, the licensee committed to install a new system for the Reactor and Turbine Buildings. Outlying structures requiring access for safe shutdown functions that are not covered by ACM powered lights will be covered by 8-hour battery lights. The new emergency lighting system will have the following attributes ~:

1. Wiring and lights configured such that multiple physically separate systems would result with each system covering a zone or quadrant. Lighting equipment in each zone will be separated by a minimum of 30 feet from that of another zone. Loss of any one 4 zone due to a postulated fire would be compensated for by the u- lights in the adjacent zones, including permanently installed but movable " extension lights" where necessary;

2. Separate and independent power feeds for each zone covered;

3. Electrical power supplied frcm the ACM diesel;

4. Breaker coordination such that only one circuit would fail given t

the loss of any one individual light unit, or a single fault such as due to a fire;

5. A minimal number of lights per circuit so that the lighting availability loss would be minimized given a circuit loss; i

6. A mix of local area lights and spot flood beams plus extension lights where necessary;

7. Receive a field check /walkdown to confirm adequate numbers, locations, and positioning of lights. -

Essential valves or equipment components requiring manual operator action (s) would be covered by local zone lighting plus spot beams from i adjacent zones. Therefore, if a fire failed the local circuit, the i

l l spot beams from a distance greater than 30 feet would still be functional. In addition, extension lights will be available in selected areas where valves are located in upper galleries.

The licensee justifies this exemption on the bases that the proposed new lighting system provides an equivalent level of emergency lighting to individual 8-hour battery packs.

2.8.3 Evaluation ,

The technical requirements of Section III.J are not met in the Reactor and Turbine Buildings because the new emergency lights are not powered by individual 8-hour batteries.

We had two concerns with the proposed emergency lighting system in these buildings. The first was that a sufficient number of lights would not be installed so as provide an adequate level of illumination. However, all essential valves and equipment components requiring manual operator actions, and access and egress routes thereto, will be covered by the local zone lighting plus spot beams from adjacent zones. In addition, at our request, the licensee in Report No.'4, comitted to verify the adequacy of the illumination by condu: ting a field walkdown with plant operators to confirm the adequacy of the numbers, locations, and positioning of the lights.

The second concern was that a fire could damage the power supply to the emergency lighting. However, the new system is designed in such a

, manner that a fire in any one zene would not affect the emergency u- lighting in adjacent zones. Therefore, individual 8-hour batteries for each emergency light are not necessary to provide us with reasonable assurance that sufficient emergency lighting would be available to complete safe shutdown functions.

2.8.4 Conclusion l

Based on our evaluation, we conclude that the licensee's alternate configuration will achieve an acceptable level of safety, equivalent d to that achieved by compliance with Section III.J. Therefore, the licensee's request for exemption for individual 8-hour battery powered emergency lighting in the Reactor and Turbine Buildings should be granted.

2.9 Exemption Request for Reactor Building 2.9.1 Exemption Requested j The licensee requested an exemption from the technical requirements of Section III.G.2 of Appendix R to 10 CFR 50 to the extent that it

~

requires that redundant shutdown-related systems be separated by 20 feet free of intervening combustibles and be protected by automatic fire detection and suppression systems.

2.9.2 Discussion The Reactor Building is a single fire area. It contains redundant components and cables associated with the turbine water removal pumps, bearing water pumps, primary coolant and S/G instrumentation, and reactor plant exhaust fans. It also contains " Train A" components and cables associated with the emergency bearing water makeup pump and

" Train B" components and cables associated with the bearing water

_ makeup pump. i The principal fire hazard in this location consists of hydraulic oil associated with the hydraulic power units and over the helium circulator-turntable. Additional combustible materials include lubricating oil and combustible cable insulation.

Existing fire protection includes automatic sprinkler systems for the hydraulic oil fire hazards and cable concentration areas, manual hose stations, and portable fire extinguishers. In Appendix R Compliance Report No. 4, the licensee comitted to install a fire detection system to provide area-wide coverage on every elevation of the Reactor Building below the refueling floor. The licensee also comitted to reroute certain shutdown-related cables to achieve at least 50 feet of horizontal separation or 30 feet of separation if an intervening floor exists between redundant systems. A portable turbine water removal

u. pump will also be provided to compensate for the potential loss of redundant turbine water removal pumps on elevation 4740 ft., 6 j inches.

The licensee justified the exemption on the existing fire protection, the proposed modifications, and the spatial separation between redundant shutdown systems.

I 2.9.3 Evaluation The technical requirements of Section III.G.2 are not met in the Reactor Building because the intervening space between redundant shutdown systems contains some combustible material. In addition, the fire detection system does not extend to the refueling floor and above, and the existing sprinkler systems do not provide area-wide coverage.

Our principal concern was that a fire of significant magnitude would damage systems associated with redundant shutdown methods. Jiowever, the major fire hazards in this area are covered by an automatic fire suppression system. Consequently, a fire involving these hazards would be mitigated by the system. Remaining combustible materials are generally dispersed throughout the remainder of the area. As a

result, a fire involving these materials would be of limited magnitude and extent and characterized, initially, by low flame propagation and ambient temperature rise.

If a fire did occur, it would be detected early by the fire detection systems. Where no detectors have been provided above the refueling floor, no shutdown systems exist. Upon actuation of the detection system or discovery of the fire by plant personnel, the control room would be notified and the fire brigade dispatched. The fire would then be either suppressed manually, using portable fire fighting equipment, or automatically, if the fire originated in the sprinkler area. Until the fire is controlled, the spatial separation between

_ shutdown systems, which in part extends over more than one floor elevation,'will provide us with reasonable assurance that a safe shutdown capability will remain free of fire damage.

2.9.4 Conclusion Based on our evaluation, we conclude that the licensee's alternate fire protection configuration, with the committed modifications, will provide an acceptable level of fire safety, equivalent to that achieved-by compliance with Section III.G.2. Therefore, the licensee's request for exemption in the Reactor Building should be granted.

2.10 Exemption Request for Turbine Building 2.10.1 Exemption Requested The licensee requested an exemption from the technical requirements of Section III.G.2 of Appendix R to 10 CFR 50 to the extent that it requires that the redundant shutdown-related systems be separated by more than 20 feet of intervening combustibles and be protected by automatic fire detection and suppression systems.

1 2.10.2 Discussion The Turbine Building houses the secondary plant equipaent including such components and systems as the turbine generator; main condenser; steam, condensate and feed systems; HVAC systems; and the emergency water booster pumps.

In Table 3.11-1 of the Appendix R Compliance Report No. 4, the licensee identified the shutdown-related systems which do not meet the separation requirements of Section III.G. The licensee committed to either: 1) Reroute fire-vulnerable cables outside of the fire area; or 2) Protect one shutdown division by a 1-hour fire barrier; or 3)

Reroute fire-vulnerable cable to achieve at least 30 feet of horizontal separation with some intervening cables from its redundant / alternate counterpart. For any other fire-vulnerable cables

1 .

or systems, the licensee has identified another means of achieving safe shutdcwn if these systems were lost due to a fire. '

The licensee justifies the exemption on the bases of the existing fire protection, the proposed modifications, the spatial separation between shutdown systems, and the availability of a number of different systems that would be relied upon to achieve and maintain safe shutdown conditions. '

4 2.10.3 Evaluation The technical requirements of Section III.G are not met in this area because redundant shutdown-related systems are not separated by more

- than 20 feet free of intervening combustibles. In addition, automatic fire suppression and detection systems are not provided throughout the area. We evaluated the lack of area-wide fire detection in Section 2.4 of this safety evaluation.

Our principal concern was that a fire of significant magnitude would damage systems associated with redundant shutdown methods. However, the major fire hazards in this area are covered by an automatic fire suppression system, or are separated by fire walls, or both. Consequently,

, a fire involving these hazards would be mitigated by the protection.

Remaining combustibles materials are generally dispersed throughout the remainder of the area. As a result, a fire involving these materials would be of limited magnitude and extent and would be characterized, initially, by low flame propagation and ambient temperature rise.

. If a fire did occur, it would be detected early by the fire detection u- system. Where no detectors have been provided, no shutdown systems exist. Upon actuation of the detection system or discovery of the fire by plant personnel, the control room would be notified and the fire brigade dispatched. The fire would then be either suppressed manually, using portable fire tighting equipment, or automatically, if the fire originated in a sprinkler area. Until the fire is controlled, the spatial separation between shutdown systems, which in part extends '

over more than one floor elevation, will provide us with reasonable assurance that a safe shutdown capability will remain free of fire damage.

2.10.4 Conclusion Based on our evaluation, we conclude that the licensee's alternate fire protection configuration with the committed modifications, will provide an acceptable level of fire safety, equivalent to that achieved by compliance with Section III.G.2. Therefore, the licensee's request for exemption in the Turbine Building should be granted.

2.11 Building 10 -

Building 10 is a new structure, erected subsequent to our " Appendix R" fire protection evaluation. It is located east of the Control Complex and is connected with it via a bridge-like walkover structure. The

j exterior walls are constructed of reinforced concrete. The floors cre concrete on earth or concrete on metal pan. The roof is constructed of concrete on metal pan. The building has been divided into six fire areas occupied for offices, computer rooms, electrical and mechanical

~

equipment rooms, and related areas. Fire protection includes fire detection systems, halon fire suppression systems, and portable fire extinguishers.

In Appendix R Compliance Report No. 4, the licensee identified one deviation from the technical requirements of Section III.G.2 of i Appendix R to 10 CFR 50. The licensee requested approval of an exemption from these requirements to the extent that they require that

' ~

structural steel which is part of a fire barrier be protected so as to achieve a fire-rating equivalent to the rating of the boundary. The '

structural steel is part of a 3-hour fire wall which separates two rooms which contain redundant shutdown-related systems. The licensee justifies the exemption on the basis of the low fire loading and the existing automatic fire protection.

The rooms on both sides of this wall are equipped with an automatic fire detection system. If a fire should occur, it would be detected in its formative stages before significant temperature rise occurs. The fire would then be put out manually using portable fire extinguishers.

If rapid fire spread occurred, we expect the automatic fire suppression system to actuate to control the fire. The system has sufficient extinguishing agent for a manually initiated second discharge if the fire 4

was not completely extinguished after the first discharge. Until the fire is extinguished, and considering the low fire loading (equivalent to

., . a 15 minute duration on the ASTM E-119 time temperature curve), it is our

judgement that the unprotected steel will remain undamaged and the i

integrity of the fire wall will be maintained. We, therefore, conclude that the licensee's fire protection configuration will provide an equivalent level of fire safety to that achieved by compliance with Section III.G. Therefore, the licensee's request for exemption for '

unprotected structural steel should be granted.

i i At our request, the licensee also submitted, in Report No. 5, dated May 1985, a comparison of the fire protection for Building 10 to the

guidelines of Appendix A to BTP APCSB 9.5-1. The licensee has

( indicated that the guidelines pertaining to the provision of a l standpipe system, yard hydrant, fire hose, and related equipment are not applicable to Building 10. We are concerned that in the event of a fire in those areas not protected by an automatic suppression

system, the licensee will not have a readily available means to apply water from hose streams onto the fire. We will require that the j licensee comply with Section C.4.h of BTP APCSB 9.5-1.

In the trip report dated September 12, 1983, which documented the results of our site audit, we stated that the licensee did not have

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within its organization or as a consultant a qualified fire protection engineer responsible for the formulation and implementation of the fire protection program.

In Report No. 5, the licensee indicated that they will be relying upon utility staff members who are " knowledgeable in fire protection system operations and fire fighting techniques." The licensee also stated that they are "taking action to procure qualified fire protection engineering services for future use." However, the licensee has not demonstrated that utility staff members are so cualified to meet our -

guidelines. Nor has the licensee provided us with reasonable assurance that an outside fire protection consultant will be "on call" for fire protection program reviews. We will require that the licensee meet the guidelines contained in Section A.1 of BTP APCSB 9.5-1.

3.0 Environmental Considerations Pursuant to 10 CFR 51.30, the staff concludes as follows regarding the listed factors:

(1)' The need for the proposed actions is described above; (2) The alternative to the exemptions would be to require literal compliance with Section IV.F. of Appendix E to 10 CFR Part 50. Such an action would not enhance the protection of the environment cnd would be adverse to the public interest generally;

! . (3) The issuance of the exemptions, or their denial, would not l affect the environmental impact of the facility; and l

l (4) That no consultation with other agencies or' persons is needed.

Based on the above assessment, the NRC staff concludes, pursuant to 10 CFR 51.32, that the issuance of these exemptions will have no significant impact on the environment.

d.0 Conclusions 4.1 Safe Shutdown Systems The concepts for providing safe shutdown under fire considerations are adequate provided the remaining open items concerning analysis of the models' cooldown effectiveness and the proposed process monitoring l instrumentation are acceptably resolved. The remaining aspects identified herein will be addressed during inspection activities.

i l

4.2 Exemptions Based on our evaluation, we conclude that the licensee's existing fire protection configuration, with the proposed modifications, achieves an equivalent level of safety to that attained by compliance with Sections III.G and III.J. Therefore, the licensee's ree,uest for exemptions in the following areas should be granted:

1. Three Room Complex (Fire Barriers)

2. Control Room (Fire Detectors)

3. Turbine Building (Fire Detectors)

4. Building 10 (Structural Steel)

5. Access Control Bay (Separation Requirements)

6. Exterior routing of shutdown cabling

7. ACM/CCA Interface Areas (Separation Requirements)

8. Common Wall-Turbine Building / Reactor Building

9. Reactor Building (Separation Requirements)

10. Turbine Building (Separation Requirements)

. , . 11. Diesel Generator Rooms (Fire Barriers) l

12. 8-hour battery pack emergency lighting 4.3 Open Items The licensee should provide additional information concerning the following open items:

Effectiveness of the Flow Paths Through the Steam Generators, (Section 2.1.2.3(a)(2)) - PSC should submit the results of the analyses discussed in References 3 and 12;

- Adequacy of Core Heat Removal Monitoring, (Section 2.1.2.3(c)(2)) -

PSC should provide an evaluation of the potential need to monitor differential temperatures (i.e., inlet and outlet) rather than the proposal to only monitor the steam generator exit for constant or decreasing temperature; l

l l

Building 10 Standpipe System, Yard Hydrants, Fire llose, and Related Equipment, (Section 2.11) - PSC should provide a commitment to comply with Section C.4.H of BTP APCSB 9.5-1 for Building 10; and Fire Protection Staff Qualifications, (Section 2.11) - PSC should provide a commitment to comply with Section A.1 to BTP APCSB 9.5-1.

Dated:

Reviewers: D. Kubicki, DPWRL-B, NRR R. Ireland, Region IV R. Mullikin, Region IV Attachments:

1. Figure 2.1-8

2. Figure 2.1-9

3. Figure 2.1-10

4. Figure 2.1-11A

5. Figure 2.1-11B e

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1 1

References

1. Appendix R Evaluation:

a. Report No. 1, Shutdown Model, November 16, 1984

b. Report No. 2, Electrical Reviews, December 17, 1984

c. Report No. 3, Fire Protection, January 17, 1985

d. Report No. 4, Exemptions and Modifications, April 1,1985.

2. Fire Hazards Analysis and Evaluation of Building 10 to the BTP 9.5-1 Appendix A Guidelines, Report No. 5, May 31, 1985.

3. NRC letter, Butcher to Lee, dated November 1,1985.

4. PSC letter, Walker to Berkow, dated December 20, 1985 (P-85488).

5. PSC letter, Walker to Berkow, dated March 14,1986(P-86209).

6. PSC letter, Walker to Berkow, dated April 4, 1986 (P-86266).

7. License Amendment No.14 with NRC letter, Denise to Walker, dated June 18, 1976.

8. License Amendment No. 18 with NRC letter, Denise to Fuller, dated October 28, 1977..

. . 9. License Amendment No. 21 with NRC letter, Gammill to Millen, dated June 6, 1979.

10. PSC letter, Warembourg to Berkow, dated May 15,1986(P-86307).

11. PSC letter, Williams to Berkow, dated July 15,1986(P-86462).

12. PSC letter, Gahm to NRC (LER 86-020), dated August 11,1986(P-86513).

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SERVICE

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f 1 r SERVICE WATER "

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SERvtCE ATER RETURN SUMP T 4201 ,

FIGURE 2.1-9 SIMPLIFIED FLOW DIAGRAM FIRE WATER FOR CIRCULATOR DRIVE & S/G COOLING TRAIN B Rev. 5

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SIMPLIFIED FLOW DIAGRAM - SERVICE WATER SYSTEM - TRAIN D Hev.5

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