ML17219A255
| ML17219A255 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 12/05/1986 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML17219A256 | List: |
| References | |
| TAC-57619, NUDOCS 8612100269 | |
| Download: ML17219A255 (13) | |
Text
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION ND M
N 1
R R
5 FLORID P
WER N
LIG AL.
1.0 INTRODUCTION
In Supplement No.
3 to the, Safety Evaluation Report (SER) for the Operating License NUREG-0843, April 1983, the staff stated that, subject to the installation of some additional fire protection features, its review of the St. Lucie, Unit 2, Fire Protection Program was complete.
By letters dated December 27,
- 1983, November 28 and December 31, 1984, February 21,
- 1985, and in Amendment No.
14 to the FSAR, the licensee pro-vided new information and identified a number of deviations from the guidelines contained in Appendix A to Branch Technical Position (BTP)
APCSB 9.5-1 and Appendix R to 10 CFR Part 50.
Our evaluation of these deviations is contained in the following sections.
2.0 FIRE DETECTION SYSTEM By letter dated December 27, 1983, the licensee requested approval of de-viations from Section III.F of Appendix R, regarding the absence of fire detection systems in the Aerated Waste Storage Tank Room and Gas Decay Tank Cubicle 2c.
These areas contain redundant safe shutdown cabling.
One train of cables is installed in a 1-hour fire-rated barrier.
The fuel load in each area is negligible.
Each area contains tanks which occupy the majority of the floor space, thus minimizing the accumulation of transient combustibles.
If a fire were to occur in these areas, it would be characterized as slow burning with limited heat buildup.
The fire would either burn until all of the combustibles were consumed or until detected by plant operators.
The fire brigade would be dispatched and would put out the fire using portable fire extinguishcrs or hand hose lines.
Pending arrival of the brigade, the 1-hour fire barrier provides reasonable assurance that one shutdown division would be free of fire
- dalllage, Based on the above, the staff finds that the installation of fire de-tectors in the Aerated Waste Storage Tank Room and Gas Decay Tank Cubicle 2c would not significantly increase the level of fire safety, and therefore, the omission of fire detection systems is an acceptable de-viation from Section III.F of Appendix R.
8612100269, 861205'DR ADOCK'05000882 F
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3.0 OTHER ITEMS RELATED TO FIRE PROTECTION PROGRAM 3.1 Fire Barrier and Fire Barrier Penetrations In revision 3 to the fire hazards analysis document dated November 28, 1984, the licensee requested approval of ll deviations (identified as A, B>,
C F
G H, I
, J P
, g
, and AA ) from Section III.G.2.$ of Apphndik R ko t3e extent th/t ih require) installing 3-hour fire-rated doors, HVAC duct dampers, and penetration seals in exterior walls of these areas.
There was concern that because of the lack of complete 3-hour fire
- barriers, a fire could damage redundant shutdown systems on each side of the existing barrier.
- However, none of the exterior walls of these fire areas (with the exception of Fire Area AA) separates redundant safe shutdown equipment.
Also, no exterior fire hazards exist near these buildings or structures.
Therefore, no deviation from Section III.G.2.a actually exists for these areas.
3.1.1.
Fire Area AA Fire Area AA, which encompasses diesel oil storage tank 2A, is separated from its redundant counterpart in Fire Area BB by a full height, 3-hour fire-rated, 18-inch-thick interior wall.
All exterior wall penetrations are sealed below elevation 29 feet 6 inches to provide a storage reservoir volume suffi-cient to contain a tank rupture and a 2-foot accumulation of fire extinguishing agent.
The Fire Area AA west wall entry point is more than 50 feet away from the entry point of its redundant counterpart.
The east wall entry has a labyrinth missile shield barrier.
The rooftop room ventilators for both Fire Areas AA and BB are more than 50 feet apart.
The rooftop tank vents for both diesel oil storage tanks are equipped with a spark arrestor and separated from each other by more than 35 feet.
Ionization smoke detectors are installed in the area on a spot basis.
This area is a light foot traffic zone, which
. minimizes the accumulation of transient combustibles.
There are no components required for hot shutdown located in this fire area.
The primary fire load consists of diesel fuel oil, which is contained in a steel tank.
Outdoor exposure fires are not postulated in the yard area near the building because of the lack of fire loading.
Also, the exterior wall penetrations are of such a height that any yard fire involving transient fire loads would dissipate to the atmosphere directly and not impact the wall opening.
Because of the low fire loads available for transient fire
- events, a fire in this fire area or in the nearby exterior yard area would not be of significant magnitude or duration.
A fire in Fire Area AA would be detected early by the fire detectors and extinguished quickly by the fire brigade.
The 3-hour fire-rated wall between Fire Areas AA and BB has no openings or penetrations
- and, hence, fire cannot spread between the redun-dant oil storage tank enclosures.
Based on the above evaluation, the staff concludes that the
'existing fire protection measures and physical plant arrangement in Fire Area AA provide a level of fire protection equivalent to the technical requirements of Appendix R.
Therefore, the absence of a complete 3-hour fire barrier in this area is an acceptable deviation from Section III.G.2.a.
Auxiliary Feedwater (AFW Pum Area By letter dated November 28, 1984, the licensee revised the fire hazards analysis document to specifically request approval for a deviation from Section III.G.2.a for not providing a 3-hour fire-rated barrier between AFW pumps A and B and their redundant counterpart, AFW pump C.
AFW pumps A and B are located within a 9-inch-thick concrete dike wall which is 2 feet 6 inches high and has a missile shield.
The missile shield is I-inch-thick steel and extends 9
feet high.
Redundant AFW pump C is located within a similar and separate enclosure.
An ionization-type fire detector is located over each pump.
The construction of this enclosure is of steel and concrete and is open to the atmosphere.
- Hence, any heat generated by' fire would dissipate vertically to the environment.
The fire loading is negligible and the area is readily accessible by the fire brigade.
In Supplement No.
3 to the SER, the staff evaluated the adequacy of the fire pi"otection for the AFW pumps and found it acceptable.
From its review of the revised fire hazards
- analysis, the staff concludes that one train of the AFW pumps would remain free of fire damage because of the low fire load, the fact that the area is open to the atmosphere, and is accessible to the fire brigade.
Should a fire occur in this area, it would be of low magnitude and short duration.
Fire detectors would annunciate in the control room and the fire brigade would quickly bring the fire under control before it disables redundant trains.
Therefore, the lack of a 3-hour fire-rated barrier between the redundant AFW pumps is an acceptable deviation from Section III.G.2.a of Appendix R, and the staff's previous conclusion is unchanged.
3.1.3 Fire Areas A
B, C, H, I, M, 0 By letter dated November 28, 1984, the licensee requested approval of a deviation from Section III.G.2 of Appendix R to the extent that it requires equivalent protection for structural supports for conduits which are protected by a fire-rated "wrap".
The requested deviations apply to the following areas:
'- Fire Area A
- Fire Area B
- Fire Area C
- Fire Area H
- Fire Area I
- Fire Ar ea M
- Fire Area 0 The deviations are identified by the licensee as A4, B
, C6, H4, I5 M3 and 09 ~
Each of the above areas contains early warning fire detection either on an area-wide or spot location basis.
Automatic fire suppression systems (except for Fire Area H) and measures for confining any flow of combustible liquids are also provided.
Fire extinguishers and hose stations are available to the areas affected.
The staff's concern in these fire areas is that in the event of a fire, the conduit supports would fail, resulting in damage to the fire wrap material which protects the conduits.
If a fire were to occur in those locations which are completely protected by an automatic fire suppression system, it is expected that the system would actuate and extinguish the fire or control it until the fire brigade arrived.
Room temperatures are not expected to reach a level which would damage either the conduit supports or the fire wrap material.
Therefore, the lack of protection for the supports in areas protected by an -automatic fire suppression system (Areas A, B, C, H, I and 0) is an acceptable deviation from Section III.G.2. of Appendix R.
For the area which has no automatic fire suppression capability (Area M) a fire would have to be controlled and extinguished by the plant fire brigade.
From the moment a fire occurs through the arrival of the brigade a significant time lapse may occur.
Normally, it is expected that it will take at least one-half hour before a fire would be considered under control and up to an hour before near-ambient conditions are restored.
If a fire
were to produce elevated room temperatures in accordance with the standard fire test of ASTM E-119, steel failure could be expected after about 10 minutes.
Because it is not possible to consistently predict the nature of fire in any plant area and because of the inherent time delays associated with fire brigade response, it is very important to have completely passive fire protection for one train of shutdown components in an area without an automatic fire suppression system.
Therefore, the absence of protection for conduit supports in such areas is an unacceptable deviation from Section III.G.2 of Appendix R.
Therefore, the staff requires that protection be provided to the supports which has equivalent fire resistance to that of the conduit barrier itself.
3.2 Fire Doors and Dam ers By letter dated December 27, 1983, the licensee identified six water-tight doors that were installed in 3-hour fire-rated barriers.
The watertight doors are located in the following loca-tions in the plant:
one door in the 3-hour barrier separating the pipe tunnel from the shutdown heat exchanger room one door in the 3-hour barrier separating the shutdown heat exchanaer room from the ECCS pump room three doors in the 3-hour barrier separating the ECCS pump room from the Auxiliary Building at Elevation
-0.5'ne door in the 3-hour barrier separating the charging pump area from the pipe tunnel The watertight doors are at least one-fourth inch thick and are similar in construction and design to watertight doors previously approved by the staff for use in 3-hour fire-rated barriers.
They are installed in high radiation areas with limited personnel
- access,
. which thereby reduces the probability of introducing transient combustibles'ach area contains early warning fire detectors, and has a low fire load.
Because of the low fuel load, a fire in any of the areas would not be of significant magnitude or duration.
It would be discovered by the early warning fire detection system and extinguished by the fire brigade before significant damage could occur.
The staff therefore concludes that these doors constitute an acceptable deviation from the criteria of Section D.l of Appendix A to BTP APCSB 9.5-1 and Appendix R,Section III.G.2.
By letter dated November 28, 1984, the licensee requested approval of two deviations (identified as h,2 and 010) from the fire protection guidelines to the extent that fire barrier penetrations and a doorway opening in the common wall between the corridor and charging pump room are not 3-hour fire-rated.
The charging pump area is located in the reactor auxiliary building at elevation 0.50 foot.
This area is separated from adjacent areas by full height reinforced concrete and concrete block walls, a
concrete floor, and roof, all having a fire rating of more than 3
hours.
The ceiling is about 20 feet high.
Ionization smoke detectors are installed throughout the area.
Fire extinguishers and hose stations are available.
A preaction sprinkler system is installed in the charging pump cubicle access area corridor.
The corridor serving the charging pump room is constructed of concrete and has full area fire detection and suppression systems.
Fire extinguishers and hose stations are available to the corridor.
The ceiling is 20 feet high and there is a negligible fire loading on the corridor floor.
In Supplement No.
3 to the SER, the staff concluded that the existing level of fire protection for these areas was adequate and that the provision of a complete 3-hour fire-rated barrier would not significantly increase the level of fire safety.
Staff review of the more recent additional information does not alter this conclusion.
The staff, therefore, concludes that the above mentioned features represent acceptable deviations from Section D.l. of Appendix A to BTP APCSB 9.5-1 and Section III.G.2 of Appendix R to 10 CFR Part 50.
4.0 EMERGENCY LIGHTING The licensee has performed an analysis of the effects on the plant safe shutdown capability resulting from a fire.
The analysis identified that manual operation of valves for cold shutdown located inside containment would be required.
By letter dated December 27, 1983, the licensee requested a deviation from Section D.5 of Appendix A to BTP APCSB 9.5-1 to the extent that it requires 8-hour battery powered lighting units inside containment to facilitate operator access to the shutdown cooling valves.
The licensee proposes to provide dedicated portable emergency lighting for containment entry.
Because manual operation of the shutdown cooling return valves may not be needed for several hours after the loss. of onsite power, the benefits provided bv 8-hour emergency lighting units may be marginal.
Thus, dedicated portable lighting units will provide acceptable illumination for containment
- access, and the installation of 8-hour emergency lighting units inside containment will not greatly enhance safety.
Based on the above, the staff concludes that the lack of 8-hour battery powered lighting units inside containment is an acceptable deviation from Section D.5 of Appendix A to BTP ASB 9.5-1 and Section III.J. of Appendix R to 10 CFR Part 50.
5.0 FIRE PROTECTION FOR SPECIFIC AREAS 5.1 Containment 5.1.1 Electrical Penetration By letter dated November 28, 1984, the licensee re-quested approval of three deviations from the fire protection guidelines (identified as A, I
, and K4) to the extent that 3-hour fire-rated elect(ical penetration seals are not provided in the containment structure.
The licensee stated that the electrical penetration assemblies are not fire rated.
The electrical penetrations consist of a primary and a secondary seal.
The primary seal is located within the 3-5/8-inch steel containment shell, and the secondary seal is located within the 36-inch concrete containment wall.
A 48-inch-wide annulus exists between the two seals.
Both seals are constructed of
'teel materials consisting of I-1/2-inch-thick by 20-inch-diameter ASME Grade A-36 plates, sleeves of 80 ASME SA 106 Grade B, 80 ASME SA 234 pipe cap, and fillet welds.
The seals are completely tested for airtightness.
The entire length of the seal is about 7 feet.
As the cables pass through the annulus, they are covered completely by a 12-inch steel sleeve.
It is the staff's judgement that the wall thickness, coupled with the seal construction, is deemed to be equivalent to a standard 3-hour fire-rated penetration seal.
The electrical penetration areas for trains A and B
are constructed of concrete.
Each of these electrical penetration rooms has fire detection and suppression svstems.
There is no fire loading on the floor.
Cables are located in covered metal cable travs or conduits.
Each room has a high ceiling.
The electrical penetration rooms are separ ated from each other by a concrete fire wall.
The containment side of these penetrations is a high radiation area and personnel access is limited, thus minimizing the probability of introducing transient combustibles.
There is no fire suppression svstem on this side of the penetrations.
The cables entering the containment side are immediately separated and a radiant energy shield is provided between safety-related A and B
cable trays.
The containment volume is large (2.5 million cubic feet) which allows for the free dis-sipation of heat and smoke.
Therefore, a fire (which would be small) would not be able to affect a seal.
The annulus area has a negligible fire load.
Because of the material of construction, airtightness, and seal arrangement, the staff concludes that the electrical penetration seals are equivalent to standard 3-hour fire rated seals.
Therefore, the lack of a fire tested and rated electrical seal assembly represents an acceptable deviation from Section D.l of Appendix A to BTP APCSB 9.5-1 and Section III.G, of Appendix R to 10 CFR Part 50.
Mechanical Penetrations By letter dated November 28, 1984, the licensee re-quested approval of three additional deviations (identified as H, J and K ) to the extent that 3-hour fire-rate3 me3hanica) penetration seals are not provided in the containment structure.
The licensee stated that mechanical penetration assem-blies are not fire-rated.
The mechanical penetrations are similar to the electrical penetrations in that they pass throuoh a 36-inch concrete containment shell.
The penetrations are welded airtight and constructed of heavy steel components similar to the electrical penetrations.
The fire load in all of the affected areas is low or negligible.
Fire detectors are installed within some of the fire zones.
- Hence, a fire would be expected to be of low severity and detected early.
Fire extinguishers and hose stations are available to these areas.
Redundant shutdown trains would not be in jeopardy at the locations of the mechanical penetration seals.
Because of the materials of construction, airtightness, and seal arrangements, the mechanical seals are equivalent to a standard 3-hour fire-rated seal.
- Further, both sides of the mechanical seal penetrations have a low fire loading and/or are protected by fire detection and suppression systems.
The containment side has a large volume that allows heat to dissip'ate and not degrade the seals.
Should a fire occur, it would be small, of short
- duration, and extinguished by automatic systems or the fire brigade.
Based on the above, the staff concludes that the ex-isting mechanical penetration seals provided for the containment penetrations are equivalent to a 3-hour fire-rated barrier and/or are sufficient to withstand the expected fire severity with conservative margin.
Therefore, the lack of standard fire tested and rated mechanical penetration seals in these areas is an acceptable deviation from Section III.G.2.a of Appendix R and Section D. 1 of Appendix A to BTP APCSB 9.5-1.
Oil Collection S stem In the SER, the staff stated that the licensee commit-ted to "provide an engineered oil collection system that meets the requirements of Regulatory Guide 1.29, paragraph C.2.".
This commitment concerned the seismic design of the oil collection system.
On this
- basis, the staff concluded that the fire protection for the reactor coolant pumps (RCPs) would be acceptable.
In the November 28, 1984 letter, the licensee requested approval of a deviation from the RCP oil collection system guidelines of Section III.O. of Appendix R to the extent that it requires the oil collection system to be capable of collecting oil from all four of the RCP lube oil systems.
The RCP oil collection tank is capable of holding 225 gallons, which exceeds the capacity of one pump
( 190 gallons).
Each RCP lube oil system has an alarm which will sound in the control room, if approximately 15 gallons of oil is lost.
The principal NRC staff concern with the existing design was that under a postulated seism'ic event, the oil collection piping, drip pans and enclosures could leak and the leaking oil would impinge upon hot sur-faces and ignite.
The design of the oil collection system was subsequently reviewed by the NRC staff (as documented in Inspection Report 85-06) and found to comply with the licensee commitment to meet the seismic design criteria of Regulatory Guide 1.29, paragraph C.2.
In addition, the licensee confirmed that the maximum allowable surface temperatures of components inside containment is 150'F as compared
- with the 450'F "flash point" of the lube oil.
On the basis of the above, the staff concludes that the lack of an oil collection reservoir capable of containing the oil from all reactor coolant pumps is an acceptable deviation from Section III.O of Appendix R
to 10 CFR Part 50.
Other Plant Areas By letter dated November 28, 1984, the licensee requested approval of two deviations (identified as H
and K ) from the fire protection guidelines to the extent that fire-rated HVAC dampers are not provided in 3-hour rated fire barriers.
Specifically, the containment and hydrogen purge makeup and exhaust systems consist of non-fire-rated piping and valves instead of the usual ducts and dampers.
The pipes have a wall thickness of about 0.375 inch compared with the 0.0312-inch thickness of a 3-hour fire-rated damper.
This pipe wall thickness exceeds the fire damper in thickness
- and, hence, would have greater fire endurance.
The containment and hydrogen purge makeup and exhaust systems are composed of 48-inch pipes, each with three remote manually operated purge butterfly valves and 8-inch pipes, each with two remote manually operated butterfly valves.
All of these valves are required by the Technical Specifications to be shut, except when in the refueling or shutdown mode.
The valves for each pipe are in separate fire areas, so a single fire would not affect all valves on any one pipeline.
Should a valve fail, the failure mode results in a closed (safe) position for the valve.
Cable routing for these valves is such that a single fire would not cause the spurious opening of all redundant valves.
All of the affected areas have a negligible fire loading.
Ionization smoke detectors are provided, but not on an area-wide basis.
Fire extinguishers and hose stations are available for use in the area.
The piping penetrations, along with the fire barriers in which thev are installed, form a continuous barrier to the propaaation of fire.
Fire detection systems are installed in these areas as described in the fire hazards analysis.
It is expected that a fire would be discovered in its initial stages by the detection
- systems, equipment-rated
- alarms, and/or plant operations personnel.
The.fire brigade would then be dispatched and would control the fire using manual fire-fighting equipment.
Pending arrival of the
- brigade, the construction of the fire barriers is such that they provide reasonable assurance that smoke and hot gases would be confined to the room of the fire and that safe plant shutdown could be achieved and maintained with systems located outside of the fire area.
On the basis of the above, the staff concludes that the above-described non-fire-rated plant features represent an acceptable deviation from Section D.l. of BTP APSCB 9.5-1 and Section III.G.2. of Appendix R to 10 CFR Part 50.
6.0 FIRE PROTECTION FOR SAFE SHUTDOWN CAPABILITY In Supplement No.
3 to the SER, the staff concluded that the fire protection for the safe shutdown capability with approved deviations was in accordance with Section III.G of Appendix R.
By letter dated December 27, 1983, the licensee requested approval of additional deviations from Section III.G.2 of Appendix R in the following areas which require the installation of a complete automatic suppression system throughout a
protected area.
Fire Area H includes the boric acid tank room, volume control tank, HVAC plenum, letdown heat exchanger, drumming storage, ion exchanger, waste and boric acid concentrators, HVAC equipment room, holdup tank room, reactor auxiliary building (RAB) corridor and east of column line RAH.
Fire Area I includes the cable loft, personnel
- rooms, post accident sampling system and radiation monitoring room, instrument repair shop and "B" train electrical penetration room.
Fire Area 0 includes RAB east hallway and miscellaneous equipment
- room, RAB east-west common hallway and the boric acid makeup pump room.
Each of the above areas contains redundant safe shutdown cabling.
One train of cabling is enclosed in a I-hour fire-rated barrier.
Early warning fire detection is installed in each area.
Automatic sprinkler systems are installed in all locations that contain redundant safe shut-down cabling and heavy cable congestion (i.e., areas containing more than six cable trays).
The combustible loading in the remaining locations in each fire area is low. If'a fire occurred in a non-sprinklered portion of any area, the early warning detection provided would alert the fire brigade.
The configuration of the areas, combined with the response of the fire brigade, would prevent a fire from growing to a size which would overwhelm the partial sprinkler systems.
The addition of more sprinkler coverage would not significantly enhance safety.
Based on the above, the staff finds the installation of partial coverage sprinkler systems i n Fire Areas H, I and 0 to be an acceptable deviation from Section III.G.2 of Appendix R.
By letters dated December 27, 1983 and November 28, 1984, the licensee also requested approval of deviations from Section III.G.2 of Appendix R which requires the installation of fire detectors.
Early warning fire detectors have not been installed in the following locations:
letdown heat exchanger room ion exchanger room waste and boric acid concentrator room holdup tank cubicles boric acid batching room hallway to the division B fan room.
The above rooms do not contain safe shutdown trains.
The fire load in these areas is negligible.
The accumulation of large quantities of transient combustibles would not be anticipated because of the massive equipment installed in these rooms.
Because of the negligible in-situ fire load, anticipated fires would involve transient combustibles and would be limited in size and duration.
The existing early warning detection and suppression system in other areas provides adequate protection for nearby safe shutdown cabling in the event of a fire in any of the above rooms.
Based on the above, the staff finds that the installation of fire detectors in the letdown heat exchanger room, ion exchanger room, waste and boric acid concentrator room, holdup tank cubicles and boric acid batching room and hallway to the division B fan room would not significantly increase the level of'ire safety.
Therefore, the lack of fire detectors is an acceptable deviation from Section III.G.2 of Appendix R.
- 7. 0 CONCLUSION Based on the staff's evaluation, the following deviations from Appendix A to BTP ASB 9.5-1 and Appendix R to 10 CFR Part 50 as described above should be granted:
1.
Six non-fire-rated watertight doors installed in 3-hour fire-rated barriers.
2.
Lack of 8-hour battery powered lighting units inside containment.
3.
Partial sprinkler coverage in Fire Areas H, I and 0.
4.
Partial early warning fire detection coverage.
5.
Lack of early warning fire detectors in the aerated waste storage tank room and the gas decay tank cubicle 2c.
6.
Exterior wall openings in Fire Area AA not provided with 3-hour fire-rated doors, HVAC dampers, and penetration seals.
7.
Lack of a 3-hour fire rated barrier between redundant division of AFM pumps.
8.
9.
Lack of a fire-rated door and two HVAC fire dampers in the wall enclosing the charging pump room and adjacent to the access corridor.
Lack of a fire-rated barrier or wrap for structural steel supports supporting steel conduits in Fire Areas A, B, C, H, I,
, and 0.
10.
Provision of unrated electrical penetration seals in the con-tainment structure that interfaces with Fire Zones 22 and 23.
11.
Provision of unrated mechanical penetration seals in Fire Zones 24, 25, and 39 and in the containment structure that interfaces with Fire Zones 22 and 23.
12.
Lack of fire-rated dampers in HVAC piping serving the con-tainment and hydrogen purge makeup and exhaust systems.
The deviation regarding lack of a fire rated barrier or wrap for structual steel supports supporting steel conduits in Fire Area N
should not be granted.
Fire protection for the supports should be provided equivalent to the conduit barrier.
Based on the above evaluation, the staff concludes that with com-'letion of the conduit support modification in Area M, the fire protection program with the approved deviations is in conformance with the guidelines of Appendix A to BTP ASB 9.5-1, the technical requirements of Appendix R to 10 CFR Part 50, and General Design Criterion 3 of Appendix A to 10 CFR Part 50 and therefore, is acceptable.
Date:
December 5,
1986 Principal Contributor:
D. Kubicki, PEICSB