ML20235J795
| ML20235J795 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 09/30/1987 |
| From: | Johnson I COMMONWEALTH EDISON CO. |
| To: | Murley T Office of Nuclear Reactor Regulation |
| References | |
| 3646K, NUDOCS 8710020098 | |
| Download: ML20235J795 (16) | |
Text
/Og Comm:nwealth Edison *
- f, [ / ' On) First National Plaza, Chicago, Illinois L'
Address Riply to: Post Office Box 76/.
~
Chicago, Illinois 60690 0767 1
September 30, 1987 j
Mr. Thomas E. Murley, Director office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Quad Cities staiton Units 1 and 2
" Transmittal of Additional Appendix R l
NRC Docket Nos. 50-254 and 50-265
.I l
l
Dear Mr. Murley:
Attached, please find a copy of an additional Appendix R exemption
~
request for Quad Cities Station for your review and approval. The need for this exemption request was identified in the course of preparation for the upcoming Appendix R inspection.
The exemption pertains to the separation of redundant reactor-
.j vessel pressure and level indication equipment. The scope of.this exemption i
request has been discussed with members of your staff-in several conference l
calls.
Please direct any questions ycu may have regarding this matter to this office.
Very truly yours, 1.
Af M -
I. M. Joh 1
Nuclear Licensing Administrator im Enclosures 1:
Exemption Request - Redundant Vessel Pressure-and Level Indication Equipment 2: Remittance: $150.00 Voucher Check 1
cc:
T. Ross - NRR l
Regional Administrator - RIII
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Quad Cities. Senior Resident Inspector 3646K i
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P QUAD CITIES 1&2-TABLE OF CONTENTS
-PAGE i
11.0 APPENDIX R EXEMPTION REQUEST FOR SEPARATION 11.0-1 OF REDUNDANT INSTRUMENTATION 11.1 JUSTIFICATION FOR SEPARATION OF REDUNDANT 11.1-1 REACTOR VESSEL PRESSURE AND LEVEL INDICATING INSTRUMENTATION 11.1.1 Introduction 11.1-1 l
11.1.2 Fire Protection System ll.1-l' 11.1.3 Fire Hazards Analysis 11.1-2 11.1.3.1 Fire Zone 1.1.1.2 11.1-2 11.1.3.2 Fire Zone 1.1.1.3 11.1-3 11.1.3.3 Fire Zone 11.2.3
.11.1-4 11.1.4 Conclusions 11.2 JUSTIFICATION FOR SEPARATION OF REDUNDANT 11.2-1
)
POOL LEVEL INDICATORS I
O k#
11.2.1 Introduction 11.2-1 11.2.2 Fire Protection System 11.2-1 11.2.3 Fire Hazards Analysis 11.2-1 l
11.2.3.1 Fire Zone 1.1.1.1 11.2-1 11.2.3.2 Fire Zone 1.1.1.2 11.2-2 11.2.3.3 Fire Zone 1.1.1.3 11.2-4 11.2.3.4 Fire Zone 1.1.2.1 11.2-4 11.2.3.5 Fire Zone 1.1.2.2 11.2-5 11.2.3.6 Fire Zone 1.1.2.3 11.2-6 11.2.4 Conclusions 11.2-7 I
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1
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QUAD CITIES 1&2 l
I 11'.0 APPENDIX R EXEMPTION REQUEST FOR SEPARATION OF REDUNDANT
()
INSTRUMENTATION Per the provision of 10 CFR 50.12, Commonwealth Edison Company (CECO) requests exemption from the requirement of Section III.G.2-of Appendix R for separation of redundant reactor vessel pressure and level indicating instruments in the Unit 1 reactor building and separation of redundant' suppression pool level indicating instruments in the Unit 1 and Unit 2 reactor buildings.
The justification for these exemptions are presented in the following sections:
1 Section Justification For i
11.1 Separation of redundant reactor j
vessel pressure and level indicating instrumentation.
O 11.2 Separation of redundant suppression pool level indicating instrumentation.
l b
11.0-1
f QUAD CITIES 1&2 11.1 JUSTIFICATION FOR SEPARATION OF REDUNDANT REACTOR VESSEL t]'
PRESSURE AND LEVEL INDICATING INSTRUMENTATION 11.1.1 Introduction Fire Area RB-1 contains cables for the redundant control room reactor level and pressure instrumentation (LIl-263-101, 100A&B, i
106A&B; LRl-263-ll3, LRl-240-26; PR1-640-27A&B).
In the event of a fire in Fire Area RB-1, local instrumentation in the reactor building (Fire Area RB-1) would be used to monitor _ reactor vessel level and pressure.
These locally monitored mechanical i
instruments are located at instrument racks 2201-5 and 2201-6 on the mezzanine floor (Fire Zone 1.1.1.3) and on rack 2201-58 in 4
1 1
the RCIC room (Fire Zone 11.2.3) on the torus level.
The requirements of Appendix R stipulate that more than 20 feet of I
horizontal space free of intervening combustibles should exist between redundant equipment and, in addition, detection and q
suppression should be installed throughout the area.
l is 1
O The subsequent analysis provides justification for an exemption to the above requirement.
The basis of the justification is that a fire in Fire Zones 11.2.3 or 1.1.1.3 would not prevent 1
operators from locally monitoring the reactor vessel level and l
pressure.
11.1.2 Fire Protection System Fire Zones 11.2.3, 1.1.1.2, and 1.1.1.3 are provided with complete fire detection with the exception of the regenerative and nonregenerative heat exchanger room, cleanup recirculation pump rooms, and cleanup decant pump phase separator pump room in Fire Zone 1.1.1.3.
Manual hose stations and portable fire l
extinguishers are located throughout Fire Zones 1.l.1.2 and l
i priw am -.l.1.1,.3-and;just1outside0the entranc~e'to FireLZone 11.2.3.
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'Q v i V
l 11.1-1 lLL
i
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QUAD CITIES 1&2 l
I I
Motor control centers 18-1A, 18-18, 18-3, 19-1, 19-1-1, 19-4, H
,~s 19-6 and 18/19-5 are located in' Fire Zones 1.1.1.3 and 1.1.1.2 (Fire Zone 1.1.1.2 is the elevation between Fire Zone l.l.l.3 and
)
11.2.3).
An inadvertent actuation of any fixed fire suppression system could result in. failure of this equipment.
- Also, installation of any other type of suppression such as cardox, halon or foam would be ineffective or inappropriate in these
]
areas because of the large volume and open stairways.
)
i i
11.1.3 Fire Hazards Analysis j
j I
11.1.3.1 Fire Zone 1.1.1.2 1
This fire zone is located above Fire Zone 11.2.3 and below Fire Zone 1.1.1.3.
For a fire to affect the areas that contain the local mechanical instruments, it would either have to start in I
this fire zone and spread to the adjacent zones or start in Fire l
Zones 11.2.3 or 1.1.1.3 and spread through this fire zone.
()
l The combustibles in Fire Zone 1.1.1.2 consist mostly of 151,600 feet of cable.
This zone is the ground floor of the reactor building.
It is frequently traveled and occasionally used as a staging area.
Transient combustibles in the fire zone include RWP clothing and limited lubricating and cleaning fluids.
These transient combustibles are controlled to minimal quantities by station administrative procedures.
Lubricating and cleaning l
fluids are only used in approved containers.
The combustible loading in the fire zone is less than 30,000 Btu /ft2 The worst case postulated fire could involve the transients and cable insulation material.
Any fire on this elevation would not expose the safe shutdown cables or equipment in Fire Zone 11.2.3 since the heat and products of combustion of the buoyant fire plume will use the ceiling and floors away from the torus level.
All electrical penetrations are sealed in the floor and ceiling with a noncombustible material.
)
11.1-2
QUAD CITIES 1&2 Available test data found in the FMRC/EPRI test reports, em
'g'
" Categorization of Cable Flammability" NP-1881,-August 1982, provide information describing the burning characteristics of PE/PVC cable in horizontal cable trays.
The heat of combustion of PE/PVC is less than 11,000 Btu /lb.
The EPRI tests show that flame spread along horizontal cable trays is very slow.
The test reports for horizontal fire spread in deep
)
stacks of horizontal cable trays agree with observations of the rate of fire spread in similar tray arrays in the reactor building at the Browns Ferry fire.
The horizontal spread rate for cable tray fires is about 6 to 7 ft/hr.
Altnough the cable tray arrangement in Fire Zone 1.1.1.2 is far less severe than that tested in the EPRI report, the parameters from those tests can be used to show a conservative fire scenario.
These parameters would indicate that only about 21 feet of cable would be consumed in a 3-hour fire.
The heat would be dissipated into an extremely large room volume.
Heat would r)
(_
also be lost to the surrounding enclosure and floor above.
Convective and radiative heat transfer effects from such a fire would obviously not affect cables in Fire Zone 11.2.3 below.
Access to the instruments on the mezzanine level would be gained through the ground floor.
This can be done either via the north stairwell or the south stairwell.
The emergency lights lighting these access paths are greater than 100 feet apart and thus both sets of lights would not be destroyed in a fire since the fire would not spread between the two halves of the floor as discussed in the paragraph above.
Fire detection throughout Fire Zone 1.1.1.2 will provide early warning of fire conditions in the zone.
This will provide ample time for manual firefighting operations to control fire spread in the trays to much less than postulated above.
Manual firefighting equipment is available in the fire zone to allow the brigade to perform this function.
11.1-3
QUAD CITIES-l&2 i
()
11.1.3.2 Fire Zone 1.1.1.3
)
1 This fire zone is the mezzanine floor of the reactor building.
Instrument racks 2201-5 and 2201-6 are located in this zone.
1 Instrument rack 2201-6 is located east of the drywell while instrument rack 2201-5 is located north of the drywell.
Both of these racks contain reactor vessel pressure and level 1
indicators.
These racks are more than 40 feet apart.
The combustibles in Fire Zone 1.1.1.3 consist mostly cf 75,700 feet of cable.
This fire zone is normally not heavily traveled during operation.
Transient combustibles are controlled to minimal quantities by station administrative procedures.
The I
combustible loading in the fire zone is less than 20,000 Btu /ft2, l
i Fire detection is provided throughout the fire zone with the j
exception of the regenerative and nonregenerative heat exchanger j
room and the cleanup decant pump phase separator pump room.
This
()
detection system will provide early warning of fire conditions which will allow the fire brigade ample time for manual q
suppression operations using available firefighting equipment in I
the fire zone.
Any fire on this elevation would not expose the safe shutdown equipment or cables in Fire Zones 1.1.1.2 or 11.2.3 since the I
heat and products of combustion of the buoyant fire plume will be carried to the levels above Fire Zone 1.1.1.3.
)
11.1.3.3 Fire Zone 11.2.3 l
The combustibles in Fire Zone 11.2.3 consist of 1568 feet of cable, 10 gallons of lube oil in the RCIC pump, turbine, drain tank and oil reservoir and the core spray pump, and 33 pounds of internal duct insulation.
The average combustible loading in this zone is less than 10,000 Btu /ft2, 11.1-4 1'
QUAD CITI.9S 1&2 The ceiling is a.2-foot 4-inch thick reinforced concrete wall q
()-
containing removable concrete slabs that allow equipment access.
Mechanical penetrations through the ceiling are sealed with a noncombustible material.
l The~ fire detection present throughout the zone will provide early warning of fire conditions.
This will allow the fire brigade ample time for manual suppression operations using firefighting equipment located just outside the entrance to the zone in Fire Zone 1.1.1.1.
The low fire loading and construction of the ceiling would confine the fire to this zone and not present a hazard to the instruments on the mezzanine level.
]
11.1.4 Conclusions The previous analysis justifies an exemption request from the j
requirements of total area suppression and more than 20 feet of horizontal intervening space free from combustibles between the f-redundant instruments.
The technical bases that justify the exemption request are summarized below.
1.
The instrument rack in the RCIC room are separated from the instrument racks on the mezzanine floor by Fire Zone 1.1.1.2.
2.
The instruments are mechanically operated and thus a fire cannot result in failure of the equipment to operate.
3.
Emergency lights are available at these instruments.
This lighting in Fire Zones 1.1.1.3 and 11.2.3 would not be affected by a fire for the same reason the instruments in the zones would not be simultaneously affected by a fire.
.r)
.NJ 11.1-5
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QUAD' CITIES l&2 11.2 JUSTIFICATION FOR SEPARATION OF REDUNDANT SUPPRESSION I
b POOL LEVEL INDICATORS l
11.2.'l Introduction-1 Fire Areas RB-1 and.RB-2 in the Unit 1 and Unit 2. reactor.
buildings contain the suppression pool level sight g2 ass 1(2)-
1 1602-10 and level transmitters 1(2)-1626, 1(2)-1641-5A and 1(2)-
1641-5B along with the' cables that provide. power and' connect <
1 these transmitters to control room' level indicators 1(2)-1602-3,
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1(2)-1640-10A and'1(2)-1640-10B.
One of these indicators must be.
l availab1'e to provide suppression pool-level' indication. 'The requirements of Appendix R stipulate that more than 20 feet of.
j horizontal space free of intervening combustibles should exist j
between redundant equipment and, in addition, detection and suppression should be installed throughout-the area.
Since the power for the transmitters is from the MCC's: located on the-mezzanine floor,.the sight glass would.have-to be used to monitor
()
suppression pool level for a fire in the northern half of the
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torus level and all levels above.
The subsequent analysis provides justification for-an'using the level sight gloss in the event of a fire in the northern half of the torus level.
The basis of the justification-is that a fire in the north end of Fire Zone 1.1.1.l(1.1.2.1) would-not prevent 1
operators from monitoring the suppression pool level.
11.2.2 Fire Protection System
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Fire Zones 1.1.1.1 and 1.1.2.1 are. protected by detection and suppression systems.
Linear thermal detectors have been installed in each cable tray and below the bottom trays in these i
fire zones.
As added protection, portions of the Division I and II trays, where they are routed within 20. feet'of each'other, are wrapped with a 1-hour rated fire resistive material.
An
){)
automatic sprinkler system has been installed at the south wall-11.2-1
QUAD CITIES 1&2 of these fire zones in the immediate vicinity of the cable risers
():
that pass through the ceiling.
The rest of the zone is proteched by manual suppression, consisting of portable CO2 extinguishers 1
and hose stations.
i Fire Zones 1.1.1.2 and 1.1.2.2 are also protected by detection and suppression systems.
Smoke detectors have been installed 1
throughout these fire zones and ionization detectors are installed above the drywell/ torus AP compressors, 48LV MCC's I
18/19-5 and 28/29-5, and the ACAD air compressors.
Manual suppression is provided in the fire zones, consisting.of portable CO2 extinguishers and hose stations.
I 11.2.3 Fire Hazards Analysis 11.2.3.1 Fire Zone 1.1.1.1 This fire zone is the Unit 1 torus level area of the reactor building.
Level sight glass 1-1602-10 is located'in this fire zone on the north side of the torus.
I 1
The combustibles in Fire Zone 1.1.1.1 consist mostly of 41,515 feet of cable.
Transient combustibles and ignition sources in the torus are strictly controlled and cannot be practically introduced due to access limitations.
The average combustible loading is less than 8000 Btu /ft2, The ceiling of Fire Zone 1.1.1.1 is constructed,of minimum 2-foot 0-inch thick concrete with all electrical penetrations sealed l
with noncombustible material.
l The linear fire detectors located in and-adjacent to the cable trays will provide early warning of a fire.
This will allow.the fire brigade ample time for manu&l suppression operations using available firefighting equipment in this fire zone.
The suppression pool level needs to be checked when torus water
(
cooling is initiated.
This occurs, at the latest, 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> into 11.2-2 L
__________-._ _ ____ __ _ a
QUAD CITIES 1&2 the event,-at which time the fire will have been been
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(,/
extinguished and the operators will have access to the sight glass.
11.2.3.2 Fire Zone 1.1.1.2 This fire zone is the ground floor level of the reactor building.
The combustibles in Fire Zone 1.1.1.2 consist mostly of 151,600 feet of cable.
This zone'is the ground floor of the reactor
]
building.
It is frequently traveled and occasionally used as a'
)
staging area.
Transient combustibles in the fire zone include RWP clothing and limited lubricating and cleaning fluids.
These transient combustibles are controlled to minimal quantities by station administrative procedures.
Lubricating and cleaning fluids are only used in approved containers.
The combustible loading in the fire zone is less than 30,000 Btu /ft2, q
The worst case postulated fire could involve the transients and (q
cable insulation material.- Any fire on this elevation would not j
expose the safe shutdown cables or equipment in the south half of l
i the torus below since heat and products of combustion of the buoyant fire plume will use the ceiling and floors away from the torus.
All mechanical, hatch, and stairwell openings in the southern portion of the floor in Fire Zone 1.1.1.2 (south of column line 16) are sealed liquid-tight with noncombustible material or curbed to prevent a liquid spill from flowing into the torus below.
All electrical penetrations are sealed in the l
floor and ceiling with a noncombustible material.
l Available test data found in the FMRC/EPRI test reports, j
" Categorization of Cable Flammability" NP-1881, August 1982,
)
provide information describing the burning characteristics of PE/PVC cable in horizontal cable trays.
i l
11.2-3 l
,o
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QUAD' CITIES 1&2 d
'The heat of combustion of PE/PVC is less th$n l'1,000fBtu/lb..The
( [2 EPRI tests show that flame spread along' horizontal cable trays: is
~
E
.very slow.
The; test'reportsLfor.horizondal firefspread in' deep stacks of horizontal' cable trays agree with observations.of the a
rate of. fire spread in similarstrayLarraysLin the' reactor building at the Browns Ferry' fir'e.."The horizontal spread rate for cable tray. fires is about 6 to 7 ft/hr.
.q l
Although the cabl'e. tray arrangemerst iin Fire Zone 1.1.1. 2 is f ar -
e I
less' severe than that tested in theLEPRI report', the parameters.
from those tests can be usedeio show a conservative fire scenario.
These parameters'would. indicate that only about 21.
feet of cable would be concume'd in.a.3-hour ~ fire.-
The heat would be dissipated into an extremely.large-room volume.
Heat would also be lost to the surrounding. enclosure and floor above.
Convective and radiativeEheat. transfer. effects from such a fire would obviously not affect cables in Fire. Zone 1.1.1.1 below.
Thus, the operators will have access to.le0el sight glass 2-1602-10.
Fire detection throughout Fire Zone 1.1.1.2 will provide'early l
warning of. fire conditions in the zone.
This will provide ample time for manual firefighting operations to. control < fire spread in the trays to much.less than postulated above.. Manual i
firefighting equipment is available in the fire zone'to allow the brigade to perform this function.
11.2.3.3 Fire Zone 1.1.2.1 This fire zone is the Unit 2 torus level area of the' reactor building.
Level sight glass 2-1602-10 isilocated in this' fire zone on the north side of the torus.
j O
11.2-4 l
I i
QUAD CITIES 1&2 1
l The combustibles in Fire Zone 1.1.2.1 consist mostly of 22,456 I) feet of cable.
Transient combustibles and ignition sources in the torus are strictly controlled and cannot be practically introduced due to access limitations.
The average combustible l
loading in the fire zone is less than 5000 Btu /ft2, l
The ceiling of Fire Zone 1.1.2.1 is constructed of minimum 2-foot j
0-inch thick concrete with all electrical penetrations sealed l
with noncombustible materials.
The linear fire detectors located in and adjacent to the cable lj trays will provide early warning of a fire.
This will allow the l
fire brigade ample time for manual suppression operations using available firefighting equipment in this fire zone.
The
]
suppression pool level needs to be checked when torus water cooling was initiated.
This occurs, at the latest, 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> into the event, at which time the fire will have been extinguished and the operators will have access to the sight glass.
l f~\\
(_)
11.2.3.5 Fire Zone 1.1.2.2 This fire zone is the ground floor level of the Unit 2 reactor 1
i 1
building.
The combustibles in Fire Zone 1.1.2.2 consist mostly of 126,200 feet of cable.
This fire zone is the ground floor of the reactor building.
It is frequently traveled and occasionally used as_a staging area.
Transient combustibles in the fire zone include anticontamination clothing and limited lubricating and cleaning fluids.
These transient combustibles are controlled to minimal quantities by station administrative procedures.
Lubricating and cleaning fluids are only used in approved containers.
The average combustible loading in the fire zone is less than 25,000 Dtu/ft2, l
The worst case _ postulated fire could involve the transients and cable insulation material.
Any fire on this elevation would not
()
expose the safe shutdown cables or equipment in the southern half 11.2-5 J
QUAD CITIES 1&2 of the torus below since heat and products of combustion of the
'( )
buoyant fire plume will rise to the ceiling and away from the torus.
All mechanical, hatch, and stairwell openings in the southern portion of the floor in Fire Zone 1.1.2.2 (south of column line 10) are sealed liquid-tight with noncombustible material or curbed to prevent a liquid. spill from flowing into the torus below.
All electrical penetrations are sealed in the l
floor and ceiling with a noncombustible material.
Available test data found in the FMRC/EPRI test reports,
" Categorization of Cable Flammability" NP-1881, August 1982, 1
provide information describing the' burning characteristics of j
PE/PVC cable in horizontal cable trays.
The heat of combustion of PE/PVC is less than 11,000 Btu /lb.
The EPRI tests show that flame spread along horizontal cable. trays is l
very slow.
The test reports for horizontal fire spread in deep.
stacks of horizontal cable trays agree with observations of the l
rate of fire spread in similar tray arrays in the reactor
()
building at the Browns Ferry fire.
The horizontal spread rate for cable tray fires is about 6 to 7 ft/hr.
Although the cable tray arrangement in Fire Zone 1.1.2.2 is far less severe than that tested in the EPRI report, the parameters j
l from those tests can be used to show a conservative fire i
scenario.
These parameters would indicate that only about 21 I
feet of cable would be consumed in a 3-hour fire.
The heat would 1
be dissipate ^ into an extremely large room volume.
Heat would j
1 also be lost to the surrounding enclosure and floors above.
)
l Convective and radiative heat transfer effect from such a fire would not affect cables in Fire Zone 1.1.2.l'below.
Thus, the operators will have access to level sight glass 2-1602-10.
l l
k
[ j V
11.2-6 1
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QUAD CITIES 1&2 i
I Fire detection throughout Fire. Zone 1.1.2.2 will provide early l
(' I warning of' fire conditions in the fire zone.
This will provide ample time for manual firefighting operations to control fire spread in the trays to much less than.that postulated above.
Manual firefighting equipment is available in the fire. zone to allow the brigade to perform this function.
l 11.2.4 Conclusions The previous analysis justifies an exemption request from the i
requirements of total area suppression and more than 20 feet of horizontal intervening space free from combustibles between the.
l redundant instruments.
The technical bases that justify the exemption request are summarized below.
1.
The level sight glass on'the torus level would not be damaged by a fire in the torus level due to the low combustible loading in the area of the sight glass.
O 2.
Torus level monitoring is not required until 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> into the event when RHR torus cooling is initiated.
At this time the fire will have been extinguished and the operators will have access to the sight glass.
3.
A fire that begins on the ground floor cannot spread to the torus level since the heat and products of combustion will rise to higher elevations.
4.
An emergency light will be placed on the floor and aimed at the sight glass when it is read.
11.2-7 l
l E__--
_ _ _ _ __ _ _ _ --_-_-_ --- _ _.