ML20210K148
| ML20210K148 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 04/11/1986 |
| From: | Ahmed N Calspan Corp, Franklin Research Ctr |
| To: | Stang J Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20210K151 | List: |
| References | |
| CON-NRC-03-81-130, TAC 11079, TAC 11080 TER-C5506-618, NUDOCS 8604160021 | |
| Download: ML20210K148 (18) | |
Text
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TECHNICAL NVALUATION REPORT NRC DOCKET NO. 50-266, 50-301 FRC PROJECT C5506 NRC LICENSE NO. DPR-24, DPR-27 FRC ASSIGNMENT 36 N RC CONTRACT NO. NRC-03-81-130 FRC TASK 618 EVALUATION OF FIRE PROTECTION EXEMPTION REQUESTS FROM 10CFR50.48 AND APPENDIX R TO 10CFR50 WISCONSIN ELECTRIC POWER COMPANY POINT BEACH NUCLEAR PLANT UNITS 1 AND 2 TER-C5506-618 i
Prepared for Nuclear Regulatory Commission FRC Group Leader: N. Ahmed Washington, D.C. 20555 NRC Lead Engineer: J. Stang l
April 11, 1986 This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, or any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or l
responsibility for any third party's use, or the results of such use, of any information, appa-l ratus, product or process disclosed in this report, or represents that its use by such third g
party would not infringe privately owned r!ghts.
j Prepared b :
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FRANKLIN RESEARCH CENTER gg gp.J.
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TER-C5506-618 1
CONTENTS Section Title Page 1
INTRODUCTION 1
1.1 Purpose of Review 1
1.2 Generic Background 1
in 1.3 Plant-Specific Background 3
L 1.4 Review Criteria.
4 2
EVALUATION 5
2.1 General 5
2.2 Service Water Pump Room Fire Zone, Elevation 7 Feet, O Inch 5
2.3 Residual Heat Removal Pump Fire Zone, Elevation
-19 Feet, 3 Inches 7
2.4 Auxiliary Building Fire Area, Elevation -19 Feet, 3 Inches; -5 Feet, 3 Inches; 8 Feet; 26 Feet; and 46 Feet.
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- i 2.5 Auxiliary Building, Elevation 46 Feet 12
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3 CONCLUSIONS 14 4
REPSRENCES 15
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TER-C5506-618 FOREWORD r t' This Technical Evaluation Report was prepared by Franklin Research Center (FRC) under a contract with the U.S. Nuclear Regulatory Commission (Office of Nuclear Reactor Regulation, Division of Operating Reactors) for technical assistance in support of NRC operating reactor licensing actions.
The technical evaluation was conducted in accordance with criteria established by the NRC.
Mr. Gregory Harrison, a consultant to FRC, contributed to the technical preparation of this report.
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TER-C5506-618 i
1.
INTRODUCTION 1.1 PURPOSE OF REVIEW l'
This technical evaluation report documents an independent review of exemptions or deviations from the fire protection requirements of 10CFR50.48 or Appendix R to 10CFR50 requested for Wisconsin Electric Power Company's (WEPCO) Point Beach Nuclear Plant Units 1 and 2.
This evaluation was performed with the
)
following objectives:
o To assess if each exemption request demonstrates an equivalent level of overall protection of plant safe shutdown capability following a disabling fire event l!
o To determine the bases for acceptance or denial of each exemption request i
t o
To recommend the minimum level of fire protection the i;
applicant or licensee should provide to achieve an equivalent level of fire protection in case a request is denied.
1.2 GENERIC BACKGROUND Following a major fire at the Browns Ferry Nuclear Station in March 1975, the NRC established a Special Review Group which initiated an evaluation of the need for improving the fire protection programs at all nuclear power plants.
The group found q
serious design inadequacies regarding fire protection at Browns Ferry, and its report, " Recommendation Related to Browns Ferry Fire" (NUREG-0050, February 1976), contained over 50 recom-mandations regarding improvements in fire prevention and control in existing facilities.
The report also called for the development of specific guidance for implementing fire protection regulations, and for a comparison of that guidance with the fire protection program l
at each operating plant.
NRC developed technical guidance from the technical recom-mandations in the Special Group's report, and issued those guidelines as Branch Technical Position (BTP) APCSB 9.5-1 [1].
This guidance did not apply to plants operating at that time.
8 Guidance to operating plants was provided later in Appendix A to BTP APCSB 9.5-1 [2], which, to the extent practicable, relies on BTP APCSB 9.5-1.
The guidance in these documents was also published as Regulatory Guide 1.120 [3].
l By early 1980, most operating plants had implemerJ6J most of the guidelines in Appendix A.
However, the fire protection program has had some significant problems with implementation.
To establish a definitive resolution of these problems in a manner consistent with the general guidelines in Appendix A to the BTP and to assure timely compliance by licensees, the Commission issued a l
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TER-C5506-618 proposed fire protection rule and its Appendix R, which was described as setting out minimum fire protection requirements for the unresolved issues.
The fire protection features addressed included protection of safe shutdown capability, emergency lighting, fire barriers, associated circuits, reactor coolant pump lubrication system, and alternate shutdown systems.
On February 17, 1981, the final rule 10CFR50.48 (4] and Appendix R to 10CFR50 [5] became effective, replacing the proposed rule.
Only three of the 15 items in Appendix R were of such safety significance that they should apply to all plants, including those for which alternative fire protection actions had been approved e
previously by the staff.
These items are protection of safe i
shutdown capability (including alternate shutdown systems),
emergency lighting, and the reactor coolant pump lubrication system.
Accordingly, the final rule required all reactors licensed to operate before January 1, 1979, to comply with these three items even if the NRC had previously approved alternative fire protection features in these areas.
However, the final rule is more flexible than the proposed rule because Item III.G now provides three alternative fire protection features which do not require analysis 4
to demonstrate the protection of redundant safe shutdown equipment, and reduces the acceptable distance in the physical separation alternative from 50 feet to 20 feet.
In addition, the rule now provides an exemption procedure which can be initiated by a licensee's assertion that any required fire protection feature will not enhance fire protection safety in the facility or that such i
modifications may be detrimental to overall safety.
.i In summary,Section III.G is related to fire protection features for ensuring that systems and associated circuits used to achieve and maintain safe shutdown are free of damage.
Either fire
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protecti*on configurations must meet the specific requirements of I
Section III.G or an alternative fire protection configuration must l
be justified by a fire hazard analysis.
Generally, the staff will
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accept an alternative fire protection configuration if:
i o
The alternative ensures that one train of equipment necessary to achieve hot shutdown from either,the control l
room or emergency control stations is free of' fire damage.
o The alternative ensures that fire damage to at least one 4
train of equipment necessary to achieve cold shutdown is limited so that it can be repaired within a reasonable time (minor repairs using components stored on the site).
o Fire-retardant coatings are not used as fire barriers.
o Modifications required to meet Section III.G would not enhance fire protection safety levels above those provided j
by either existing or proposed alternatives.
o Modifications required to meet Section III.G would be i
detrimental to overall facility safety. :
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TER-C5506-618 Guidance to the industry and the NRC positions on certain requirements of Appendix R is covered by various documents, one of them being the Generic Letter'83-33 [6] which has recently been slated to be superseded by yet another draft Generic Letter 85-01 (7].
"The interpretations of Appendix R" and "the responses to industry questions," two sections of Reference 7, are written to i
facilitate industry implementation of Appendix R and represent NRC i
position on all issues covered.
4 Following the promulgation of the final rule, licensees and applicants have requested exemptions and deviations from Appendix R to 10CFR50.
The exemptions and deviations are in the form of a fire hazard analysis.
The NRC is to review exemption requests and associated analysis to ensure each alternative to meeting the requirements of the rule provides an equivalent level of overall protection of plant safe shutdown capability.
Franklin Research Center (FRC) was to provide technical assistance tc the NRC within l
the context of the following scope of work (8):
Subtask 1:
Review each exemption request for information deficiencies. Provide Request for Information i
(RFI) to resolve such deficiencies.
!I Subtask 2:
Review and evaluate each exemption or deviation request submitted by the licensees or the applicants and all additional information provided i
for conformance with acceptance criteria.
Prepare final Technical Evaluation Report (TER) with 1
recommendations, and their basis in support of granting or denying the exemption / deviation request.
1.3 PL NT-SPECIFIC BACKGROUND By letter dated June 30, 1982, the Licensee submitted its response to 10 CFR 50 Appendix R.
This response contained a fire ll hazards analysis, which was also the foundation for the requested exemptions.
By draft SER dated January 14, 1983, the NRC denied all requested exemptions except.for the control room and the l
hydrogen hazard fire protection analyses.
On March 22, 1983, an appeal meeting was held with the NRC and, as a result, the Licensee submitted another document dated April 28, 1983.
This submittal 8
revised certain exemption requests, withdrew unnecessary cnes,
(
proposed numerous plant modifications, and created two new exemption requests pertaining to the auxiliary building.
By letter dated July 3, 1985, the NRC approved exemption requests for Fire Zones 1, 2,
3, and 7 and Fire Areas 5 and 8.
Exemption requests for Fire Zone 10 and portions of Fire Zone 2 and Fire Area 8 were determined not to be required.
By letter dated August 21, 1985, the NRC denied the switchgear room (Fire Area 6) exemption request.
The residual unevaluated exemption requests now include the two new ones in the Licensee's April 28, 1983 submittal and the two exemption requests identified in the Licensee's October 1983 final report.
TER-C5506-618 The Request for Information (RFI) required in satisfaction of Subtask 1 was transmitted to the NRC on November 31, 1985 [9].
l' A site visit was made on November 26, 1985 to gather information requested in the RFI and to walkdown the areas where exemptions were requested.
The draft TER [10] was issued to NRC on January 21," 1986.
The contents of the draft reflected the information contained in the Licensee's submittals identified above.
This final TER incorporates all comments received from NRC to date on the draft TER.
1.4 REVIEW CRITERIA The criteria used in reviewing the Licensee-submitted exemption requests are based on the following documents:
1.
Fire Protection Program for Operating Nuclear Power Plants, 10CFR50.48 2.
Appendix R to 10CFR50 8
3.
Standard Review Plan, NUREG-0800, Branch Technical Position (BTP), APCSB 9.5-1,
" Guidelines for Fire i
Protection for Nuclear Power Plants" l'
4.
Appendix A to BTP APCSB 9.5-1
)
5.
Generic Letter 85-01, " Fire Protection Policy," dated January 9, 1985.
O e
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TER-C5506-618 2.
EVALUATION I
2.1 GENERAL 1
This section presents review and evaluation of exemptions or deviations from 10CFR50.48 or Appendix R to 10CFR50 requested by the Licensee (WEPCO) of. Point Beach Nuclear Plant Units 1 and 2.
Evaluation of exemption requests for each fire area / zone singly or collectively follows a format suggested by the NRC and is arranged in the following subsections:
o Exemption requested o
Discussion Y
o Evaluation o
Conclusion.
The fire area / fire zone numbering used in this section corresponds to that used in the Licensee's submittal.
2.2 Service Water Pump Room Fire Zone, Elevation 7 Feet, O Inch 2.2.1 Exemption Requested D
An exemption was requested from Section III.G.2.b to the extent that it requires 20 feet of separation without intervening combustibles between redundant safe shutdown equipment.
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2.2.2 Discussion The service water pump room fire zone is a separate pump room within the circulating water pumphouse.
This fire zone is i
constructed of. reinforced concrete and metal panel wall sections.
The roof and one wall are common components between the service water pump room and the circulating water pumphouse.
The subject fire zone is on elevation 7 feet, o inch.
The upper section of the common and east walls are constructed of metal grate; therefore, there is a free exchange of air between the service water pump room and the circulating water pumphouse.
The entrance to the service water pump room is via a security door in the east wall.
Within 3
the service water pump room, there is a partial-height, noncombustible wall that divides the six service water pumps into two sets of three.
Currently, there is an access opening in this divider wall.
The Licensee has committed to seal this opening and install a new door into the second set of service water pumps.
This new door will be located in the east wall.
The service water pump room is a rectangular shaped room with a ceiling height of 22 feet.
The total room area is about 1,000 square feet.
There is essentially no fire loading on the floor proper and the primary fire load consists of diesel fuel for the l L.
TER-C5506-618 fire pump.
This fuel oil is in a day tank located 32 feet away in the circulating water pumphouse and its piping is within the concrete floor.
The day tank ~is in a sump, which can contain the total diesel fuel volume of 250 gallons.
There are no intervening combustibles located within the service water pump room that would serve a pathway between the two separated sets of three service water pumps.
The total fire loading is 13,600 Btu per square foot, which translates into a fire severity of less than 12 minutes as represented by the ASTM E-119 time-temperature curve.
There are no concentrated fire loads or hazards within the service water pump room.
The safe shutdown systems in the service water pump room j
include the six service water pumps for Units 1 and 2.
There are no exposed power or control cables.
Also, there are no service water motor-operated valves required for safe shutdown.
Any one of the six service water pumps is capable of providing the required service water flow for both units to achieve stable hot shutdown.
In addition, any +wo of the six pumps are required for both units to achieve cold shutdown.
i The existing fire protection includes area-wide smoke detection and an automatic wet pipe fire suppression system that has redundant connections to the fire main.
Manual fire fighting capability is in the form of fire extinguishers and two 1 1/2 inch hose real stations located adjacent to the entrance doors.
Although 20 feet of separation without intervening combustibles is not available between redundant systas, the Licensee has installed b
a partial-height, noncombustible wall between the service water pumps such that they are divided into two sets of three.
This wall j
is liquid tight at the bottom.
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$ valuation i
The fire protection in the service water pump room fire zone l
does not comply with the technical requirements of section il III.G.2.b of Appendix R because 20 feet of separation without intervening combustibles has not been provided between redundant 4
safe shutdown equipment and cables related to the service water system.
The principal concern with the level of fire protection in the service water pump room was that because of the lack of a 20-foot separation free of intervening combustibles, a fire of significant magnitude could develop and damage redundant safe shutdown systems.
i However, the fire load in these locations is low.
If a fire were I
to occur, it is expected to develop slowly, with initially low heat release and slow room temperature rise.
Because of the presence of the early warning fire detection systems, the fire would be detected in its incipient stages.
The alarms from these detectors are annunciated in the control room.
The fire brigade would then be dispatched and would extinguish the fire manually.
Until the fire was put out, the noncombustible partial-height partition between the two sets of shutdown service water pumps and the
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TER-C5506-618 automatic sprinkler system would provide sufficient passive and active fire protection to provide reasonable assurance that two of the total of six service water pumps would remain free of fire damage.
Another major factor that reduces fire risk in this fire zone is the six redundant safe shutdown system service water. pumps are separated into two groups of three pumps with no intervening combustibles.
This physical separation is accomplished by a partial-height, noncombustible radiant energy heat shield that is installed in this zone.
It is found that the provision of 20 feet t
of separation with no intervening combustibles would not significantly increase the level of fire protection in the service water pump room fire zone.
2.2.4 Conclusion Based on the above evaluation, it is concluded that the existing fire protection combined with the committed fire protection measures in the service water pump room provide a level of fire protection equivalent to the technical requirements for Section III.G.2.b of Appendix R.
Therefore, the exemption request for the aforementioned zone can be granted.
2.3 Residual Heat Removal Pump Fire Zone, Elevation -19 Feet, 3 Inches 2.3.1 Exemption Requested D
i An exemption was requested from the specific requirement of
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Section III.G.2.b to the extent that automatic fire suppression is
'not inst'alled within the common residual heat removal (RHR) pump i
room area.
2.3.2 Discussion The RHR pump room is a fire zone and is below grade at elevation -19 feet, 3 inches.
This fire zone is constructed of floors, ceilings, and walls having 3-foot-thick reinforced concrete.
There are four RHR pump rooms that open into a middle room or vestibule.
This divides the zone into two sets of RHR 1
pumps each RHR pump in its own room.
Two RHR pumps are for Unit O
1 and two RHR pumps are for Unit 2.
An open stairway exists between the upper elevation (-5 feet, 3 inches) and the common room.
The wall of each RHR pump room that faces the middle common i
room has a 4-foot-square opening for access.
This access is at the top and, hence, a short metal ladder is provided.
The common wall i
between each RHR pump room is solid with no penetrations.
The ceiling height in this zone is 11 feet.
Each RHR pump room is about 88 square feet and th9 common middle room is 573 square feet in area.
There are no fire loads on the floor in this zone.
The only fire loading is in the form of i :
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TER-C5506-618 the RHR electric motors and 2 quarts of lubricating oil in each RHR pump.
There are no intervening combustibles.
Therefore, the total firc load is negligible.
Also, there are no concentrated fire loads or fire hazards.
The safe shutdown equipment in this zone consists of the four RHR pumps in two pairs.
Only one of each pair is required for safe shutdown of the two units. There are no power or control cables required for hot shutdown located in this fire zone.
Any cable damaged can be replaced or repaired within the time span allowed for cold shutdown.
The existing fire protection includes a fire detection system throughout the fire zone.
There is no automatic fire suppression system installed within the zone.
Manual fire fighting capability exists within the auxiliary building in the form of fire extinguishers and hose stations.
The 1 1/2-inch hose station on i
elevation 8 feet, O inch can be used for the RHR fire zone.
The l
Licensee does not propose any modifications for this zone.
2.3.3 Evaluation The fire protection in the RHR pump fire zone does not comply with the technical requirements of Section III.G.2.b of Appendix R because an automatic fire suppression system has not been installed throughout the fire zone.
The principal concern with the level of fire protection in the RHR pump fire zone was that, because of the absence of an area-wide automatic fire suppression system, a fire of significant magnitude could develop and damage redundant RHR pumps.
However, the fire
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load in these locations is negligible.
If a fire were to occur, it is expected that it would develop slowly, with initially low heat b
release and slow room temperature rise.
Because of the presence of the early warning fire detection systems, the fire would be detected in its incipient stages.
The alarms from these detectors are annunciated in the control room.
The fire brigade would then I
be dispatched and would extinguish the fire manually.
Until the fire was put out, the reinforced concrete barriers between the redundant RHR pumps would provide sufficient passive protection to provide reasonable assurance that one shutdown division of RHR i
pumps would remain free of fire damage.
Another major factor that reduces the fire risk in these' fire zones is that redundant RHR pumps are separated by a solid, reinforced concrete wall that runs from floor to ceiling with no in-situ combustibles.
It is found that the installation of an automatic fire suppression system would not significantly increase the level of j
fire protection in the RHR pump fire zone.
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2.3.4 Conclusion l
Based on the above evaluation, it is concluded that the i
existing level of fire protection for the RHR pump fire zone provides a level of fire protection equivalent to the technical 4
requirements for Section III.G.2.b of Appendix R.
Therefore, this exemption request for the aforementioned zone can be granted.
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2.4 Auxiliary Building Fire Area Elevations -19 Feet, 3 Inches;
-5 Feet, 3 Inches; 8 Feet; 26 Feet; and 46 Feet i
2.4.1 Exemption Requested An exemption was requested from the specific requirement of Section III.G.2.b to the extent that automatic fire suppression is not installed throughout the fire area.
2.4.2 Discussion l
The auxiliary building is composed of numerous zones and several small fire areas.
It can be viewed as having north, south, and west wings with a central area.
The elevations range from -19 feet, 3 inches to 46 feet.
In the west wing, the elevations range from -19 feet, 3 inches to 46 feet.
The RHR pumps are located at i
the -19 feet, 3 inch elevation; this is a separate exemption request (see Section 2.3 of this report).
The other three elevations of -5 feet, 3 inches; 8 feet; and 46 feet are j
constructed of reinforced concrete.
Penetration seals to other plant structures and construction joints are 3-hour fire rated.
4 Docrs exiting this area are 3-hour fire rated.
These elevations are open to each other via an open stairwell and equipment hatch.
The only safe shutdown equipment located herein are the RHR heat exchangers, which are in separate compartments; the 480-V motor control centers B33 and B43; and the component cooling water heat exchangers.
There are no safe shutdown equipment or cables required for hot shutdown located herein.
Also, safe shutdown cables are routed in conduit and there are no cable trays in the
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area.
Redundant trains of RHR cables are located on all elevations of this wing in configurations which are susceptible to damage from a single fire.
However, the RHR system is not required for hot shutdown.
The Licensee has committed to provide a dedicated set of l
RHR pump cables for each unit.
The fire loading in this wing ranges from 8,000 to 28,000 Btu per square foot.
This translates into a fire severity of less than 21 minutes as represented by the ASTM F-119 time-temperature curve.
I Fire protection for the west wing consists of an area-wide i
fire detection system,, fire extinguishers, and two 1 1/2 inch hose i
real stations located on the 9-foot elevation.
The Licensee j
verified that the lower elevations can be serviced by one of these hose stations.
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The south wing at elevation 8 feet contains the auxiliary j
building exhaust fan room, HVAC equipment room, laundry and I o
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c TER-C5506-618 chemical drain tank room, RCP seal water filter area, Unit 1 CVCS charging pump rooms, and MCC 1-B32 room.
The exhaust fan rooms contain no safe shutdown equipment and are a fire area because of the 2-and 3-hour fire rated enclosure components, which includes the doors.
HVAC room 159 contains the exhaust fans and the Unit I red and blue channel instrument cables.
The room enclosures are -2 and 3-hour fire rated components and the doorway openings are protected by an automatic water spray system.
Therefore, these 3
pump rooms are actually separate fire areas, as is room 156.
The I
absence of an automatic fire suppression system in room 156 was evaluated and granted by the NRC in an exemption request dated July 3,
1985; similarly this is also true for the safety injection pump room.
The component cooling water pumps are susceptible to damage l
from a single fire, but they are not required for hot shutdown.
A j
spara pump and cables are being provided for the purpose of a repair.
The redundant divisions of charging pump cables are located here, but they too have been exempted from the Appendix R requirement for automatic fire suppression.
In general, construction throughout the south wing zones and areas is concrete.
Penetrations and construction joints adjacent to other plant structures are 3-hour fire rated seals.
Doors j'
exiting this structure are 3-hour fire rated.
Fire loadings do not exceed 24,000 Btu per square foot except for charcoal filters.
This translates into a fire severity of 18 minutes, as represented by the ASTM E-119 time-temperature fire test curve.
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Fire protection for the south wing zones and areas within the J
auxiliary building consists of a fire detection system throughout, j
fire extinguishers, and hose real stations.
Also, several locations have wet pipe sprinkler system coverage.
The north wing has elevations 8 and 26 feet and is identical in terms of construction to the previously described portions of 9
the south and west wings.
That is, the walls, floor, and ceilings are either 3-hour fire rated or are 18-inch-thick concrete.
The interior doorways to rooms have automatic water spray protection.
Penetrations and doors to adjacent plant structures are 3-hour fire i
rated.
l The north wing only contains safe shutdown equipment in the form of three charging pumps (one each in a concrete cubicle) and a i
MCC 2-B32 room.
Also, redundant RCS instrumentation for both units is at elevation 26 feet.
Just as in the south wing for Unit 1 charging pumps, the Unit 2 charging pump rooms do not have an automatic fire suppression system.
However, this aspect has already been granted an exemption from Appendix R,Section III.G.2.b.
The fire loading in these zones and areas is less than 8,800 Btu per square foot, which translates into a fire severity of less than 7 minutes based on the ASTM E-119 time-temperature curve.
The exception to this fire loading value are the charcoal filters and i
TER-C5506-618 i
gas decay tanks, which have already been approved by the NRC in the August 1979 SER for not having a fire suppression system.
Fire protection for the north wing consists of an area-wide fire detection system, fire extinguishers, partial coverage by wet pipe sprinkler systems, and hose stations.
2.4.3 Evaluation The fire protection in the auxiliary building does not comply with the technical requirements of Appendix R,Section III.G.2.b i
because an automatic fire suppression system has not been installed i
i throughout the area.
The principal concern with the level of fire protection in the i
l auxiliary building was that, because of the absence of an area-wide automatic fire suppression system, a fire of significant magnitude j
could develop and damage redundant shutdown systems, e.g.,
the Mccs or CCWs.
However, the fire load in these locations is low.
If a fire were to occur, it is expected that it would develop slowly, with initially low heat release and slow room temperature rise.
Because of the presence of the early warning fire detection systems, the fire would be detected in its incipient stages.
The alarms from these detectors are annunciated in the control room.
a The fire brigade would then be dispatched and would extinguish the
?
fire.
Until the fire was put out, either the 20 feet of horizontal j
separation or concrete fire barriers between the redundant shutdown systems would provide sufficient passive protection to provide reasonable assurance that one shutdown division would remain free of fire damage.
In the case of the redundant RHR j-cables subject to damage from a single fire, spara cables have been
. committed to be made available for a repair, which is acceptable, j"
i since the RHR system is not required for hot shutdown.
The same
!J applies to the CCW cables and pumps.
Also, a spara CCW pump will be provided and kept available in addition to the necessary cables.
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Finally, in rooms 166, 142, 151, and 156, automatic sprinkler systems already exist.
Also, areas such as the RHR pump room and 1 '
six charging pump rooms have been previously evaluated and approved with respect to the absence of an automatic fire suppression l-system.
The above areas represent over one half of the total auxiliary building area.
Therefore, the balance of areas represent non-critical areas containing no hot shutdown equipment and low fire loadings.
It is found that the installation of additional i
automatic fire suppression systems would not significantly increase j
the level of fire protection in the auxiliary building.
2.4.4 conclusion s
Based on the above evaluation, it is concluded that the existing fire protection combined with the Licensee committed fire protection measures in the above fire zones provide a level of fire 4
protection equivalent to the technical requirements of Section III.G.2.b of Appendix R.
Therefore, this exemption can be granted.
TER-C5506-618 2.5 Auxiliary Building, Elevation 46 Feet t
2.5.1 Exemption Requested An exemption was requested from the specific requirement of Section III.G.2.a to the extent that the floor of the auxiliary building central area on elevation 46 feet is not a 3-hour rated barrier.
2.5.2 Discussion The construction and layout of the auxiliary building are 1
presented in detail in the preceding exemption request (section 2.4 of this report).
Essentially, the auxiliary building is a single fire area composed of numerous zones and rooms.
Some of the rooms are, in actuality, small fire areas.
The total auxiliary building i
fire area was established by completely enveloping the areas of seismic construction with 3-hour fire rated barriers except for the central area floor on the 46-foot elevation.
This elevation contains open stairways, doorways, and several hatches.
Therefore, l'
the Point Beach auxiliary building does not satisfy the specific requirement of Appendix R for a fire area enclosure to be of a 3-hour fire rating.
is The majority of the elevation 46 feet level floor penetrations 9
terminate on the 26-foot elevation, and alternate safe shutdown and charging pump cable reroutings to the 8-foot elevations will be provided.
Therefore, hot shutdown would not be affected.
Floor penetrations in the open floor span of elevation 46 feet are ql provided with 3-hour fire rated seals except for several hatches.
?
These hatches, however, are kept closed with a concreto and steel
. plug.
Although not formally fire rated, these plugs would be
,I highly fire resistive because of the mass and thickness of the 3l hatch plug.
Because these hatches were required for maintenance l
access, no combustibles, cable trays, or safe shutdown equipment are located nearby or within the intervening vertical spaces.
The
- '6 open stairway is located 45 feet away from Unit 2 Division "A" charging pump cable routings.
The CCW system heat exchangers are
{.
on elevation 46 feet, but they are in a separate rated compartment.
With the exception of the CCW heat exchangers, there are no safe shutdown equipment ' cut cables located on the 46-foot elevation.
F Fire protection consists of a fire detection system, fire extinguishers, and 1 1/2-inch hose reel stations.
The fire load is low (8000 Btu per square foot), and translates into a fire severity of less than 6 minutes as represented by the ASTM E-119 time j
temperature curve.
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TER-C5506-618 2.5.3 Evaluation The fire protection in thk auxiliary building, elevation 46 feet does not comply with the technical requirements of section III.G.2.a of Appendix R because a complete 3-hour fire rated barrier has not been provided at the floor level within the central area.
The principal concern with the level of fire protection in the auxiliary building central floor area at elevation 46 feet was that, because of the absence of a complete 3-hour fire rated floor, a fire of significant magnitude could develop and damage redundant safe shutdown cables at lower levels.
However, there is a low fire load on the floor area and there are no cables or equipment required for hot shutdown in and within the central area.
If a fire were to occur, then it is expected that it would develop
+
slowly, with initially a low heat release and slow area temperature rise.
Because of the presence of the early warning fire detection system, the fire would be detected in its incipient stages.
The i
alarms from these detectors are annunciated in the control room.
The fire brigade would then be dispatched and would extinguish the L
fire.
Until the fire was put out, the existing floor with its j
hatch covers (without intervening combustibles) between the central l
i floor area on elevation 46 feet and the location of safe shutdown equipment and cables on the lower elevations would provide i
sufficient passive protection to assure that one division would remain free of fire damage.
It is found that the provision of a 3-hour fire rated barrier for the floor level would not t
significantly increase the level of fire protection in this zone.
2.5.4 Conclusion Basid on the above evaluation, it is concluded that the existing fire protection for the auxiliary building central floor area at elevation 46 feet provides a level of fire protection equivalent to the technical requirements of Section III.G.2.a of Appendix R.
Therefore, this exemption for the aforementioned zone can be granted.
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TERoC5506-618 3.
CONCLUSIONS This section is provided evaluation contained in Sectio,to consolidate the results of the n 2 concerning the exemptions of Appendix R to 10CFR50 for Point Beach Nuclear Plant Units 1 and 2.
It is not meant as a substitute for the specific conclusions reached in the various subsections of Section 2 for which the reader is referred to specific subsections.
Based on the evaluation, the existing fire protection and/or proposed fire protection modifications in the aforementioned areas provide a level of fire protection equivalent to the technical requirements of Section III.G of Appendix R and, therefore, the j
following exemptions from the requirements of Section III.G of Appendix R are deemed reasonable and can be granted.
1.
Service Water Pump Room Fire Zone, Elevation 7 feet, 0 inch, to the extent that 20 feet separation free of intervening combustibles is not provided in this zone pursuant to III.G.2.b.
Section 2.2 provides additional j
information.
]
2.
Residual Heat Removal Pump Fire Zone, Elevation -19 feet, i.
3 inches to the extent that an automatic fire suppression system is not installed within this zone pursuant to III.G.2.b.
Section 2.3 provides further information.
3.
Auxiliary Building Fire Area, Elevations -19 feet, 3 q
inches; -5 feet, 3 inches; 8 feet; 26 feet; and 46 feet to h
the extent that an automatic fire suppression sytem is not installed throughout the area pursuant to III.G.2.b.
j Section 2.4 provides further information.
' Auxiliary Building, Elevation 46 feet to the extent that 4.
a 3-hour fire rated floor barrier is not provided in central zone of the auxiliary building pursuant to III.G.2.a.
Section 2.5 provides further information.
l k
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TER-C5506-618 4.
REFERENCES BTP APCSP 9.5-1 " Fire Protection Program," July 1981 (Standard 1.
Review Plan, NUREG-0800) i 2.
Appendix A to BTP APCSP 9.5-1, " Guidelines for Fire Protection for Nuclear Power Plants Docketed Prior to July 1,.1976,"
August 23, 1976 3.
Regulatory Guide 1.120, " Fire Protection Guidelines for Nuclear Power Plants," November 1977 l
4.
10CFR50, " Fire Protection Program for Operating Nuclear Power Plants," November 19, 1980 5.
Appendix R to 10CFR50, " Fire Protection Program for Nuclear Power Facilities Operating Prior to January 1, 1979," November 19, 1980 6.
Generic Letter 83-33, "NRC Position on certain Requirements of Appendix to 10CFR50," October 19, 1983 7.
Generic Letter 85-01, " Fire Protection Policy," January 9,
- j 1985 8.
Final Work Assignment No. 36, transmitted by M. Carrington
~
(NRC) to Dr. S. Pandey (FRC) on July 17, 1985 a
9.
Requests for Information (RFI), transmitted by N.
Ahmed (FRC) to J. Stang (NRC) on November 13, 19E5 10.
Draft TER, transmitted by N. Ahmed (FRC) to J. Stang (NRC) on January 21, 1986 i
Dated April 11, 1986 Il I
e.
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