ML20127P489
| ML20127P489 | |
| Person / Time | |
|---|---|
| Site: | Farley  |
| Issue date: | 06/26/1985 |
| From: | Mcdonald R ALABAMA POWER CO. |
| To: | Varga S Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8507020429 | |
| Download: ML20127P489 (11) | |
Text
i Calling Address a. Alibima Power Company 600 North 18th Street Post Office Dox 2641 Birmingham. Alabama 35291 Telephone 205 783-6090 R. P. Mcdonald NZs'a0%*o*"'
NabamaPower June 26, 1985 tres_.- m m :-
Docket No. 50-364 Director, Nuclear Reactor Regulation U. S. Nuclear Regulatory Comission Washington, D.C.
20555 Attention: Mr. S. A. Vi rga Joseph M. Farley Nuclear Plant - Units 1 and 2 10CFR50.48 and 10CFR50, Appendix R Fire Protection Exemption Requests Gentlemen:
By letter dated March 13, 1985, Alabama Power Company submitted technical exemption requests from the provisions of 10CFR50, Appendix R 4
for all Unit 2 and shared fire areas in Farley Nuclear Plant.
Subsequent to this submittal, it was determined that fire areas 2-001 and 2-009 contained control cables for instrument air isolation valve N2P19HV3825-A. Therefore, attached for NRC approval, pursuant to 10CFR50.12(a), are revisions to exemption request numbers 2-019 and 2-036 for fire areas 2-009 and 2-001, respectively. The revised exemption requests postulate the effects upon this valve resulting from loss of thef control cables caused by a fire in these areas.
If there are any questions, please advise.
Yours truly,
/
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R. P. Mcdonald RPM /DHJ:bdy-D6 cc: Mr. L. B. Long Dr. J. N. Grace Mr. E. A. Peeves Mr. W. H. Bradford y
Mr. G. F. Trowbridge lg0 asgq#2gegoyg;4 F
L
4 J. M. FARLEY NUCLEAR PLANT 10CFR50 APPENDIX "R" FIRE HAZARDS ANALYSIS REEVALUATION EXEMPTION REQUEST:
2-19 Rev.1 FIRE AREA: 2-009
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LOCATION: TRAIN "B" INSIDE CABLE CHASES, AUXILIARY BUILDING EXEMPTION:
Request exemption from Section III.G.2.c to the extent that it requires one train of redundant safe shutdown cables to be enclosed by a barrier having a 1-hour fire rating.
CONDITIONS REQUIRING EXEMPTION / MODIFICATION a)
Instrument Air Fire area 2-009 contains electrical Train-B power and control cable raceways. The analysis of the potential effects of a fire in this area upon cabling shows that j
the plant could lose the entire electrical Train-B system. Due to loss of the electrical Train-B system, the following redundant safe shutdown values could 4
become inoperable in the closed position.
i EQUIPMENT FUNCTION N2P19HV3885-B Instrument Air to Penetration Room i
Q2B13HV2228-B Backup Air /N2 Supply to Pressurizer PORY's i
Q2B31PCV0445A-A Pressurizer PORV, Train-A Q2B31PCV0444B-B Pressurizer PORV, Train-B 4
Q2E21HV8145-N Pressurizer Aux. Spray 4
In addition, Fire Area 2-009 contains control cables directly associated with N2P19HV3885-B and N2P19HV3825-A. The analysis of the potential effects of a fire j
in the area upon these cables shows the valves could become inoperable in the 2
closed position.
4 b) Reactor Coolant Boundary i
Fire area 2-009 contains control cables for the Train B pressurizer pcwer operated relief and blocking valves Q2B31PCV0444B-B and Q2B13MOV80008-B, and the reactor head vent valves Q2B13SV22138-B and Q2813SV22148-B, the subject cables are associated with control from both the hot shutdown and main control board. A fire induced failure having multiple hot shorts could cause the reactor inventory to letdown via the PORY and Reactor Head Vent pathes.
c) Auxiliary Feedwater i
i Auxiliary feedwater isolation valves Q2N23MOV3764B, Q2N23MOV3764C, Q2N23M0V3764E i
are redundant to one another from the point of view that they isolate flow in i
redundant auxiliary feedwater supply lines. Control cables for all three valves i
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4 l
2-19-1 Rev.1
ars rcut:d through the fire area. Th2 analysis of the potential effects of a fire on these control cables shows that spurious operation of the auxiliary feedwater isolation valves could occur.
d) Component Cooling Water Fire area 2-009 contains a control cable for the CCW Heat Exchanger 2B service water discharge valve (Q2P16SV3009-B). A fire induced failure resulting in a hot short from adjacent cables in the same raceway, could energize the solenoid and close the valve.
PROPOSED MODIFICATION AND JUSTIFICATION FOR EXEMPTION JUSTIFICATION a) Instrument Air - Justification Failure of valve Q2E21HV8145-N in the closed position will disable the Pressurizer Aux. Spray system which provides one method to achieve depressurization of the RCS. Pressurizer PORV's Q2B31PCV0445A-A and Q2831PCV0444B-B provide another means of achieving RCS depressurization. Valves N2P19HV3885-B, Q2B13HV2228-B and N2P19HV3825-A could fail in the closed position as a result of fire damage.
This will isolate the instrument air supply to the Pressurizer PORV's Q2B31PCV0445A-A and Q2831PCV04448-B. PORV Q2B31PCV0444B-B will also be inoperable due to loss of the Train-B DC power supply. However, the Train-A DC supply to PORV Q2831PCV0445A-A is not affected due to a fire in this area. Since only one of the PORV's is required for RCS depressurization and RCS depressurization is a long tenn requirement, the operator has adequate time to take manual action to restore the l
instrument air by hand wheel operation of valve N2P19HY3885-B and N2P19HV3825-A.
Once air is restored, PORY Q2B31PCV0445A-A will be operable to achieve RCS depressurization, b) Reactor Coolant Boundary - Justification Fire induced failure (Hot short) of the individual control cables for Q2831PCV0444B-B power operated relief valve and Q2B13SV2213B-B, Q2B13SV22148-B reactor head vent valves, could result in the valves to be energized to open. The power operated relief blocking valve (MOV) could become electrically inoperative in the open position.
In the unlikely event of the multiple fire induced failures (Hot shorts from adjacent control cables in the shared raceway) occuring this condition can be mitigated by removing 125VDC power from cables in the shared raceway. This can be accomplished by opening breaker on the 125VDC Switchgear Bus 2B (Q2R428001B-B) for 125VDC Distribution panels, 2D, 3E and 2F.
Plant procedures will be revised to include the above action for a fire in area 2-009.
Auxiliary Feedwater - Modification The control cable associated with at least one of the auxiliary feedwater isolation valves will be protected by two 1-inch layers of Kaowool blanket with an overall layer of Zetex fabric or it will be rerouted out of the fire area. The subject valves and associated cables are as follows:
Q2N23MOV3764B: 2VBFV-MSC Q2N23MOV3764C: 2VBFV-Y2C Q2N23M0V3764E: 2VBFY-R2C 2-19-2 Rev. 1
[.
d) Compared Cooling Water Justification The service water discharge valve (Q2P16SY3009-B) is required to be in the open position only when the swing CCW Pump 2B is aligned to electrical Train-A.
In the unlikely event of such hot shorts resulting in the closed of service water discharge valve, the valve can be manually repositioned.
FIRE PROTECTION:
A smoke detection system and automatic water suppression system are provided throughout the chase.
In addition, water hoses and portable extinguishers located in room 2185 (Area 2-6) and room 2319 (Area 2-42) are available for use in the area.
FIRE AREA INFORMATION:
ROOM NUMBERS / TITLES SHUTDOWN COMBUSTIBLE QUANTITY FIRE LOAD MAXIMUM TRAIN MATERIAL (Btu /ft2)
FIRE SEVERITY 2117, 2198, 2247, B
Cable-4,489 lb 2,921,199 9 Hours 2338 Cable Chase Insulation 2246, 2344 Cable B
Cable-2,135 lb 180,180 2-1/2 Hours Chase Insulation DESIGN FEATURES:
Construction: Floor, ceiling and walls forming the area boundary are of reinforced concrete.
Doors: Airtight UL Class A doors are located between rooms 2198 and 2185 (Area 2-6) and between rooms 2338 and 2335 (Area 2-41); an airtight UL Class A door exists between rooms 2344 and 2343 (Area 2-41).
Piping and Electrical Penetrations: All penetrations through the area boundary are sealed with silicone foam or Nelson fittings.
Ventilation: There is no normal ventilation for this area.
Fixed smoke removal capability has not been provided.
Floor Drains: There are no floor drains.
2-19-3 Rev. 1
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l J. M. FARLEY NUCLEAR PLANT 10CFR50 APPENDIX "R" FIRE HAZARDS ANALYSIS REEVALUATION EXEMPTION REQUEST:
2-36 Rev. 1 FIRE AREA: 2-001 LOCATION: UNIT 2 AUXILIARY BUILDING ELEVATIONS 83 '-0", 100 '-0", 121 '-0" Fire area 2-001 consists of the following rooms:
Elevation 83'-0" Room 2101 Waste Decay Tank Room Room 2102 Valve Compartment Room Room 2103 Corridor Room 2104 Passageway to Unit 1 Room 2105 Catalytic H2 Recombiner A Room Room 2106 Catalytic H2 Recombiner B Room Room 2108 Waste Monitor Tank Room Room 2109 Waste Monitor Tank Pump Room Room 2110 Monitor Control Penel Room Room 2111 Containment Spray Pump Room A Room 2112 Access to Tendon Access Gallery Room 2113 Valve Encapsulation Room 2114 Pipe Chase Room 2115 Hallway Room 2118 Floor Drain Tank Room Room 2119 Waste Holdup Tank Room Room 2120 Corridor Room 2121 Floor Drain Tank Pump Room Room 2122 Waste Evaporator Feed Pump Room Room 2123 Pipe Chase Room 2124 Valve Encapsulation Room 2125 Containment Spray Pump Room B Room 2126 Pipe Chase Room 2127 Pipe Chase Room 2128 RHR Heat Exchanger Room Room 2129 RHR Low Head Pump Room B Room 2130 Pipe Chase Room 2131 RHR Low Head Pump Room A i
Elevation 100'-0" Room 2183 Tendon Access Gallery Entrance Room 2184 Piping Penetration Room EL 100'-0" Room 2169 Pipe and Duct Chase Room 2196 Tendon Access Gallery Elevation 121'-0" l
j Room 2223 Piping Penetration Room EL 121'-0" l
2-36-1 Rev. 1 i
All of the fire area boundary walls, floors, and ceilings are rated as three-hour fire barriers except for a non-rated steel hatch cover in the floor slab of el.100'-0" which separate room 2103 (area 2-001) and room 2163 (area 2-004). All electrical and piping penetrations are sealed for a three-hour rating. All doors in the boundary walls are UL Class A or Class B rated.
1 EXEMPTION: An exemption is requested from Section III.G.2.c to the extent it requires one train of redundant safe shutdown cable to be enclosed by a barrier having a one-hour fire rating and automatic fire suppression. This exemption is based upon the implementation of the proposed modification for this fire area.
CONDITIONS REQUIRING EXEMPTIONS:
Exemptions are required for safe shutdown related cable and equipment as described below.
a)
Instrument Air Isolation A fire induced failure in control cables for instrument air isolation valve Q2P19HV3611 and N2Pi9HV3825-A may cause the valve to fail closed. A loss of instrument air causes the normal charging line isolation valve Q2E21HV8146 and the alternate charging line isolation valve Q2E21HV8147 to fail open.
It may be necessary to close these valves during the course of shutdown to isolate charging flow.
A fire induced failure in the control cable for the pressurizer PORV backup air /N2 supply valve Q2B13HV2228-B may cause the valve to fail closed.
If instrument air isolation valve Q2P19HV3611 or N2P19HV3825-A and the pressurizer PORY backup air /N2 supply valve Q2B13HV2228-B fail closed, the pressurizer PORV's will be inoperable in the closed position.
Operation of the pressurizer PORV's may be required to achieve depressurization of the RCS.
b)
Initiation of Safety Signals Fire Area 2-001 contains instrumentation cables associated with the following redundant Containment Pressure instrument channels.
PT950-P1 CTMT Pressure Channel 1 PT951-P2 CTMT Pressure Channel 2 PT952-P3 CTMT Pressure Channel 3 PT953-P4 CTMT Pressure Channel 4 These instrument loops are not required for post fire safe shutdown, but due to fire induced failures, the circuitry could cause initiation of safety signals (SI, CI, and CVI).
c) Main Steam Atmospheric Relief Control cables associated with the three redundant atmospheric relief valves are routed through Fire Area 2-001. An analysis of potential effects of a fire upon these cables has shown that the subject valves could become inoperable in the closed position.
2-36-2 Rev.1
4 Charg'ng Pump Miniflow
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d) i Power and control cables associated with charging pump miniflow isolation valve MOV8106-A are routed through fire area 2-001. An analysis of the potential effects of a fire upon these cables has shown that MOV8106-A could close and isolate the charging pump miniflow line.
e) Reactor Coolant Boundary Integrity Control cables for the Train-A pressurizer power operated' relief and blocking valves Q2B31PCV0445A-A and Q2B13MOV8000A-A, and the reactor head vent valves Q2B13SV2213A-A and Q2B13SV2214A-A are located in fire area 2-001. The subject cables are associated with the control function from the hot shutdown panel Q2H21NBAFP2605G-A.
In addition control cables which shift control from the main control-board to the hot shutdown panel via the transfer relay cabinet Q2H22L002-A are in this area. A fire induced failure having multiple hot shorts could cause the reactor inventory to ledown via the PORV, and Reactor Head Vent paths.
PROPOSED MODIFICATIONS AND JUSTIFICATIONS FOR EXEMPTION:
PROPOSED MODIFICATIONS:
E To bring the boundaries of fire area 2-001 into compliance with the requirements of a three-hour fire barrier, the steel hatch cover 7ocated in the EL 100'-0" floor
=
slabs between rooms 2103 (Area 2-001) and 2163 (Area 2-004) will be modificed. The hatch cover will be modified to meet the requirements of a three-hour fire barrier or water curtains will be provided and the hatch cover sealed to prevent passage of 4
liquids, smoke or gas to adjacent fire areas.
JUSTIFICATIONS:
4 a)
Instrument Air Isolation - Justification Instrument air isolation valves Q2P19HV3611 and N2P19HV3825-A are l
l equipped with a handwheel to facilitate manual operation.
In the l
event the valves fail closed an operator can manually open them. Thisltc action will restore instrument air to the charging line isolation valves and the pressurizer PORV's. Consequently action would not have to be taken on the pressurizer PORY backup air /N2 supply valve Q2B13HV2228-B.
l b)
Initiation of Safety Signals - Justification Fire induced cable failures in fire area 2-001 to non post fire safe shutdown circuitry could potentially result in a false SI, CVI, or CI safety signal initiation from the solid state protection system.
Plant procedures exist for reseting spurious SI, CVI, and CI safety 4
signals from the main control room and can be used if required for a j
fire in this area.
3 i
Il
'o 2-36-2 Rev. A a
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c) Main Steam Atmospheric Relief - Justification j'
One of the three Main Steam Atmospheric Relief Valves and related i
steam generator is required to be operable to achieve steam release for cooldown. The atmospheric relief valves are provided with hand wheels such that the valves may be manually opened or closed without electrical controls or air supplies. The operator would establish manual control of the atmospheric relief valves by closing the manual air control valves to isolate the air supply and by opening the manual air vent valve to bleed off air from the diaphragm of the valve operator. Both the air control and air vent valves are located in the vicinity of their associated atmospheric relief valve and would be accessible despite a fire in area 2-001. The capability to control steam generator pressure and reactor coolant system temperature with the use of the manually controlled atmospheric relief valves was demonstrated during the Unit-2 natural circulation and cooldown startup testing. Consequently, a fire in area 2-001 would not prevent the operation of at least one redundant atmospheric relief valve.
d) Charging Pump Miniflow - Justification Valve Q2E21MOV8106-A is required to be maintained open to establish l
charging pump miniflow.
In the event this valve fails closed, miniflow will be discontinued. The charging pump can be run safely with miniflow isolated and with a minimum of 24 gpm of seal injection flow for a period of up to one hour. This will allow the operator time to take manual action to open the valve and re-establish miniflow.
4 I
e) Reactor Coolant Boundary Integrity - Justification Fire induced failures (hot shorts) to the control cables for the transfer relay cabinet Q2H22L002-A could cause control for the power operated relief and blocking valves and the reaction head vent valves, to shift from there normal main control board alignment ot the remote hot shutdown panel. Subsequent fire induced failures (hot shorts for adjacent control cables in the shared raceway) of the control cables for Q2831PCV0445A-A, power operated relief valve, and Q2B13SV2213A-A, 2813SV2214A-A reactor head vent valves, could result in the valves being energized to open. The power relief blocking valve (MOV) could become electrically inoperative in the open position.
In the unlikely event of the multiple hot shorts occuring, this condition can be mitigated by removing power from the transfer relays and manual operation (handle) of the effected relay thereby shifting control to i
the main control board.
1 Plant procedures will be revised to include the above actions for fire area 2-001.
ROOM NUMBERS / TITLES SHUTDOWN COMBUSTIBLE QUANTITY FIRE LOAD MAXIMUM TRAIN MATERIAL (Btu /ft2)
FIRE SEVERITY 4
Cable 29 lb(a) 1,251 (a) 30 Min 2101 Waste Gas Decay l
Tank Room insulation 2102 Valve Cable Compartment Room insulation 2-36-4 Rev. 1
- ~
ROOM NUMRERS/ TITLES SHUTDOWN COMBUSTIBLE QUANTITY FIRE LOAD MAXIMUM TRAIN MATERIAL (Btu /ft2)
FIRE SEVERITY 2103 Corridor B
Cable insulation 2105 Catalytic H2 B
Cable 490 lb ins.
7,634(b) 30 Min Recombiner A Room insulation (b)
Panels 28 lb panels Cable 2106 Catalytic H2 Recombiner B Room Panels 2104 Passageway B
Cable to Unit-1 insulation 2109 Waste Monitor B
Cable 417 lb ins 5,742(c) 30 Min Tank Pump Room insulation (c)
Lube oil 0.25 gal oil (c)
Cable 14 lb 2110 Monitor Control Panel Room insulation panel (c)
Panels Cable 75 lb 19,457 30 Min 2108 Waste Monitor Tank Room insulation Charcoal 375 lb filter 0
0 None 2169 Duct and Pipe Chase Cable 22 lb 831 30 Min 2118 Floor Drain Tank Room insulation Cable 60 lb 2,711 30 Min 2119 Waste Holdup Tank Room insulation 2120 Corridor B, C Cable 42 lb 5,540 30 Min insulation l
2121 Floor Drain B, C Cable 287 lb 21,402 30 Min l
Tank insulation l
Pump Room Lube oil 0.25 gal 2122 Waste Evaporator B, C Cable 287 lb 21,402 30 Min Feed insulation Pump Room Lube oil 0.25 gal 2127 Pipe Chase B, C None 0
0 0
2128 RHR Heat A, C Cable 454 lb 2,607 30 Min Exchanger Room insulation 2129 RHR Low Head B, C Cable 217 lb 3,837 30 Min Pump Roan B insulation None 0
0 0
2130 Pipe Chase Cable 222 lb 6,332 30 Min 2131 RHR Low Head Room A insulation 2-36-5 Rev. 1
ROOM NUMBERS / TITLES SHUTDOWN COMBUSTIBLE QUANTITY FIRE LOAD MAXIMUM TRAIN MATERIAL (Btu /ft2)
FIRE SEVERITY None 0
0 0
2126 Pipe Chase Cable 7 lb 2124 Valve Encapsulation insulation Cable 261 lb 3,569 30 Min 2125 Containment Spray Pump Room B insulation Lube oil 0.25 gal Crble 7 lb 3,885 30 Min 2114 Pipe Chase insulation Cable 101 lb 3,469 30 Min 2111 Containment Spray Pump Room A insulation Lube oil 0.25 gal Cable 6 lb 2113 Valve Encapsulation insulation Cable 4 lb 1,655 30 Min 2115 Hallway insulation Cable 4 lb 175 30 Min 2112 Access to Tendon Access Gallery insulation Cable 4 lb 175 30 Min 2196 Access to Tendon Access Gallery insulation None 0
0 0
2123 Pipe Chase 2183 Tendon Access A
Cable 1,050 lb(d) 6,405(d) 30 Min Gallery Entrance insulation 2184 Piping Penetration Room, EL 100'-0" 2223 Piping A, B Cable 16,663 lb 40,625 1 Hour Penetration Room, insulation EL 121 '-0" Charcoal 400 lb (a) Applies.to rooms 2101 and 2102 collectively (b) Applies to rooms 2103, 2105, 2106 collectively (c) Applies to rooms 2104, 2109, 2110 collectively (d) Applies to rooms 2183 and 2184 collectively DESIGN FEATURES:
Construction: Floors and walls forming the area boundary are of reinforced concrete. The ceiling of room 2223 has tendon access openings to room 2334 (Area 2-34). Steel plates with three-hour rated coatings and which are topped by removable concrete slabs have been installed over the tendon access openings.
2-36-6 Rev. 1
Doors: An airtight, UL Class B door is installed between room 2223 and stairway No. 2.
The door between room 2184 and roo.n 2162 (Area 2-4) is an airtight UL Class A door. Nonairtight Class B doors are installed between room 2110 and 2115 and stairway No. 2.
Piping and Electrical Penetrations: Penetrations through the area boundary are sealed with silicone foam. Three-hour rated fire dampers are installed between 2169 and 2163 (Area 2-4).
Ventilation: No normal ventilation exists. Fixed smoke removal capability has not been provided.
Floor Drains: Twenty-one 4-in. diameter floor drains with a 100-gal / min capacity each are located throughout the area. Sumps are provided in rooms 2103, 2111, 2125, 2128, 2129, and 2131. The sumps contain two 100-gal / min pumps each. The The floor sump pumps discharge to the waste holdup tank or the floor drain tank.
The other floor drains drains above EL 77 -83' drata to the floor drain tank.
drain to the sumps.
FIRE PROTECTION:
A detection system covers the majority of the area.
Exceptions to this coverage are rooms 2112, 2114, 2115, 2123, 2126, 2127, 2130, 2169, 2196. The western half of the Piping Penetration Room on EL 121'-0" is the only part of fire area 2-001 covered by automatic suppression.
Portable carbon dioxide extinguishers, portable dry chemical extinguishers, smoke removal equipment and water hose cabinets are located throughout the fire area for use by the fire brigade.
JUSTIFICATION FOR FIRE PROTECTION:
The rooms in fire area 2-001 without detection (2112, 2114, 2115, 2123, 2126, 2127, 2130,2169,2196) contain little or not combustible material and contain no safe shutdown cable or equipment.
The western half of the Piping Penetration Room on EL 121'-0" is the only part of fire area 2-001 covered by an automatic suppression
. system. This is the only part of fire area 2-001 that has cables or equipment that are associated with redundant hot shutdown systems.
One train of redundant cables are provided with fire barriers consisting of two 1-inch layers of Kaowool blanket with overall layer of Zetex cloth within this area.
2-36-7 Rev.1
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