ML20215G321

Forwards Addl Info for 860509 Request for Exemption from Certain Requirements of 10CFR50,App R Re Fire Suppression Sys & 3 H Fire Barrier Requirement,Per 860918 Request

ML20215G321
Person / Time
Site:	Point Beach
Issue date:	10/10/1986
From:	Fay C WISCONSIN ELECTRIC POWER CO.
To:	Harold Denton, Lear G Office of Nuclear Reactor Regulation
References
CON-NRC-86-98 GL-86-10, TAC-11079, TAC-11080, VPNPD-86-422, NUDOCS 8610200318
Download: ML20215G321 (8)

Text

1 WISC0nSin Electnc powea couraur 231 W. MICHIGAN,P.O BOX 2046. MILWAUKEE,WI53201 (414)277-2345 VPNPD-86-422 NRC-86-98 October 10, 198f Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. NUCLEAR REGULATORY COMMISSION Washington, D.C. 20555 Attention: Mr. George Lear, Director PWR Project Directorate #1 Gentlemen:

. DOCKET NOS. 50-266 AND 50-301 10 CFR 50 APPENDIX R EXEMPTION REQUESTS POINT BEACH NUCLEAR PLANT UNITS 1 AND 2 By letters dated April 28 and October 26, 1983, as supplemented in a letter dated December 11, 1985, Wisconsin Electric Power Company requested, pursuant to 10 CFR 50.12, exemptions from certain requirements of 10 CFR 50 Appendix R, " Fire Protection Program for Nuclear Power Facilities Operating Prior to January 1, 1979," for our Point Beach Nuclear Plant, Units 1 and 2. Several exemptions were' granted by a NRC letter dated July 3, 1985.

Effective as of January 13, 1936, 10 CFR 50.12 requires that special circumstances exist to support a requested exemption. In our May, 9, 1986 letter, we cited special circumstances to support our exemption requests on the basis that " Application of the regu-lation in the particular circumstances would not serve the under-lying purpose of the rule or is not necessary to achieve the underlying purpose of the rule." By letter dated September 18, 1986, the NRC stated that citing special circumstances was inade-quate and that a discussion of why implementation of features required by the rule is not warranted for each exemption requested is necessary. As requested by your September 18 letter, a discus-sion for each requested exemption is provided in the attached Enclosure 1.

Very truly yours, 8610200318 861010 PDR ADOCK 05000266 G// l-

' 0c ' - p PDR C. w. Fay Vice President

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-Nuclear Power j ug Copy to NRC Resident Inspector k

ENCIOSURE 1 EXEMPPION REQUESTS l

1. Requested Exemption We have requested an exemption from the total area automatic fire suppression requirement of Appendix R.Section III.G.2.b for the Point Beach Nuclear Plant auxiliary building in our April 28, 1983 letter.

Discussion By letter dated June 30, 1982 we had requested exemption from the separat' ion and automatic fire suppression requirements of Appendix R for 5 groups of fire zones, in the auxiliary building, which contain equipment that is required for safe shutdown. These exemptions were discussed with the NRC staff at a March 22, 1983 meeting in Bethesda. Modifications ade-quate to protect safe shutdown capability which were agreed upon at the meeting included cable rerouting or wrapping,.

fire stop installation, alternate shutdown instrumentation independent of upper floors and provision of less than full area automatic suppression for each group of fire zones.

These exemptions were granted ty the NRC in a letter dated

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July 3, 1985. The implementation of modifications is progres-sing toward completion by the end of the fall 1986 Unit 2 refueling outage. On the basis that partial suppression is adequate for zones which contain vital safe shutdown equip-ment, the provicion of full fire area suppression including zones without safe shutdown equipment is not required.

Generic Letter 86-10, Enclosure 1, Section 5 states that in order to comply with provisions of Appendix R, Sections III.G.2.b and III.G.2.c, suppression and detection sufficient to protect against the hazard of the area must be installed.

Section 5 states further that .the licensee must perform an evaluation to assess the adequacy of partial suppression and detection which may be submitted to the staff for review and concurrence. Our exemption request was submitted and the exemption was granted prior to the issuance of GL86-10. We believe that the granting of the previous exemptions, which include partial area automatic suppression, signifies staff concurrence that adequate suppression and detection capa-bility is provided.

The above discussion demonstrates that suppression and detec-tion sufficient to protect against the hazards of the area is being provided in the auxiliary building. Therefore, provi-sion of total area automatic suppression capability would not serve the underlying purpose of the rule nor be necessary to achieve the underlying purpose of the rule and this exemption should be granted.

2. Requested Exemption We have requested an exemption from the literal 3-hour fire barrier requirement of Appendix R,Section III.G.2, for the 46 foot elevation of the Point' Beach Nuclear Plant auxiliary building in our' April 28, 1983 letter.

Discussion The~ intent of this exemption is to obtain relief from the literal definition of a' fire area because the building boundaries are penetrated by open doorways, stairways, and hatchways. Open doorways provide access to a room on the 46 foot elevation which contains mechanical equipment and

-instrument cables which are used for safe shutdown. The mechanical equipment has been evaluated to be of sufficient durability to withstand a postulated fire. Alternate shut-down capability is being provided on lower elevations for safe shutdown cable.

One stairway penetrates from the 46 foot elevation into an open room between the residual heat removal pump rooms of each unit at the-(-)19 foot elevation. Redundant pump cables could be damaged by a fire along the route of this stairway.

Dedicated spare cables are provided for this cold shutdown equipment in accordance with Appendix R requirements.

An open hatch and an open stairway penetrate into the fire zone at the 8 foot elevation which contains component cooling water pumps, redundant trains of residual heat removal pump cables for both units, redundant trains for Unit 2 charging pump cables and alternate shutdown instrument caoles. An exemption from the separation and automatic fire separation requirements of Appendix R was requested for this fire zone by our June 30, 1982 letter and discussed at the March 22, 1983 meeting. Modifications adequate to protect safe shut-down capability which were_ agreed to by the staff include the wrapping of one train of Unit 2 charging pump- cable, pro-vision of dedicated' spare residual' heat removal pump cables, provision of doorway specific automatic suppression, provis-ion.of automatic suppression east of the open hatchway and around the perimeter of the stairway, and the provision of 3-hour rated penetration seals in the ceiling above the sprinklered area. The exemption was granted July 3, 1985 and the modifications were implemented by April 3, 1986. On the basis that equipment within this fire zone is adequately protected, additional barrier protection at the 46 foot elevation is not required.

Generic-Letter 86-10, Enclosure 1, Section 4 states that the term " fire area" as used in Appenoix R means an area suffi-ciently bounded to withstand the hazards associated with the area and, as necessary, to protect important equipment within i the area from a fire outside the area. In order to meet the regulation, fire area boundaries need not be completely sealed floor-to-ceiling, wall-to-wall boundaries. Section 4 states further that the licensee must perform an evaluation to assess the adequacy of fire boundaries which may be sub-mitted to the staff for review and concurrence. Our exemp-tion request was submitted and the exemption was granted prior to the issuance of GL 86-10. We believe that granting of the exemption for the component cooling water pump room signifies staff concurrence that important equipment located therein is adequately protected. Cable penetrations in the-auxiliary building boundary are sealed in accordance with the requirements of Appendix R,Section III.M.

The above discussion demonstrates that boundary protection sufficient to withstand the hazards associated with the area is provided in the auxiliary-building. Therefore, additional boundary modification would not serve the underlying purpose of the rule and this exemption should be granted.

3. Requested Exemption We have requested an exemption from the automatic fire sup-

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pression system requirement of Appendix R,Section III.G.2.b for the Point Beach Nuclear Plant, auxiliary building, resi-dual heat removal pump fire zone in our October 26, 1983 sub-mittal.

Discussion The Unit 1 and Unit 2 RHR pumps are separated by approxi-mately 50 feet and two 3-ft thick concrete walls. Access to individual pump rooms is provided by openings located 7 feet above the floor. The two RHR pumps for each unit are sepa-rated by approximately 15 feet between center lines and have a 3-ft thick concrete wall between them. Cables in the fire zone are routed in conduit and the zone is essentially free of fixed combustibles. Each room is provided with two photo-electric smoke detectors. Hose lines and portable fire extinguishers are available to provide manual fire suppres-sion capabability. In order to affect both pumps in the same unit, a fire would have to propagate from one pump room to the other or from the common room to both pump rooms. This is evaluated to be improbable because of the existing sepa-ration by 3-ft thick concrete walls, height of the access openings, absence of intervening combustibles and furnished fire detection. Therefore, we have determined that additional fire protection measures are unnecessary and none have been implemented.

Generic Letter 86-10, Enclosure 1, Section 5 states that in order to comply with the provisions of Appendix R, Sections III.G.2.b and III.G 2.C, suppression and detection sufficient to protect against the hazards of the area must be installed.

The information submitted with our October 26, 1983 letter as summarized in the discussion in the preceding paragraph demonstrates that compliance with these provisions has been-achieved. Therefore, the provision of total area automatic fire suppression capability would not serve the underlying purpose of the rule nor be necessary to achieve the under-lying purpose of the rule and the exemption should be granted.

4. Requested Exemption We have requested an exemption from the automatic fire suppression system requirements of Appendix R,Section III.G.3 for the Point Beach Nuclear Plant, auxiliary building, component cooling water heat exchanger and boric acid tank room in our letter dated June 11, 1986.

Discussion The room is located on the 46-foot elevation of the auxiliary building. The room is separated from other building areas by non-fire rated concrete walls having a minimum thickness of 18 inches. The walls, ceiling and floor are provided with 3-hour fire rated penetration seals. The room is accessed from the west side through one 3 ft x 7 ft and one 12 ft x 13 ft doorless entranceways and via an open stairway through the floor. The room is provided with 6 photoelectric smoke detectors. Hose lines and portable fire extinguishers are available to provide manual fire suppression capability. The room contains 4 component cooling water heat exchangers and redundant trains of instrument cables for both units which are used to achieve safe shutdown. Two heat exchangers are normally required but one heat exchanger could provide cold shutdown capability for both units over a longer period of time. The two outermost heat exchangers are separated by 21 feet between center lines. The heat exchangers have been evaluated.to be of sufficient durability to withstand a postulated fire. Safe shutdown cables in the component cooling water heat exchanger room are a continuation of cables from the monitor tank roon immediately beneath the component cooling water heat exchanger room. Our April 28, 1983 letter had requested a similar exemption from the auto-matic fire suppression requirements of Section III.G.2.b for the monitor tank room on the basis that alternate shutdown capability would be provided for safe shutdown instrument cables. The exemption was granted July 3, 1985 and imple-mentation of modifications is proceeding toward completion by

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the end of the fall 1986 Unit 2 refueling outage. Therefore, alternate shutdown capability is being provided for safe shutdown instrument cables located in the component cooling water heat exchanger room.

Generic Letter 86-10, Enclosure 1, Section 5 states that in order to comply with'the provisions of Appendix R, Sections III.G.2.b and III.G.2.c, suppression and detection sufficient to protect against the hazards of the area must be installed.

The information submitted with our June 11, 1986 letter as summarized in the discussion in the preceding paragraph demonstrates that compliance with these provisions has been achieved. We believe that the previously granted exemption for the monitor tank room signifies staff concurrence that sufficient protection is provided. Therefore, the provision of automatic fire suppression capability would not serve the underlying purpose of the rule nor be necessary to achieve the underlying purpose of the rule and this exemption should be granted.

5. Requested Exemption We have requested an exemption from the automatic fire suppression system requirements of Appendix R,Section III.G.3 for the Point-Beach Nuclear Plant computer and instrument rack room in our letter dated June ll, 1986.

Discussion The room is located on the 60-foot elevation of the control building. The room boundaries are reinforced concrete walls, floor, and ceiling. All boundaries are provided with 3-hour fire-rated penetration seals. The room is accessed from the north and south through class A fire doors. The room is pro-vided with 8 photoelectric smoke detectors. Hose lines and portable fire extinguishers are available to provide manual fire suppression capability. The combustible loading which consists of cable insulation is considered to be moderate.

Safe shutdown equipment located in the room consists of redundant primary and secondary system instrument cables for both units which are used to achieve safe shutdown. These instrument cables are a continuation of cables routed through the auxiliary building monitor tank and component cooling water heat exchanger rooms. Our April 28, 1983 letter had requested a similar exemption from the automatic fire suppre-ssion requirements of Section III.G.2.b for the monitor tank room on the basis that alternate shutdown capability would be provided. The exemption was granted July 3, 1985 and imple-mentation of modifications is proceeding toward completion by the end of the fall 1986 Unit 2 refueling outage. Therefore, alternate shutdown capability is being provied for safe shut-down instrument cables located in the computer -and instrument rack room.

Generic Letter 86-10, Enclosure 1, Section 5 states.that in order to. comply with the provisions of Appendix R, Sections III.G.2.b and III.G.2.c, suppression and detection sufficient to protect against the hazards of the area must be installed.

The information submitted with our June ll, 1986 letter as summarized in the discussion in the' preceding paragraph demonstrates that compliance with these provisions has been achieved. We believe that the granted exemption for the monitor tank room signifies staff concurrence that sufficient protection is provided.

Therefore, the provision of automatic fire suppression capa-bility would not serve the underlying purpose of the rule nor be necessary to achieve the underlying purpose of the rule and this exemption should be granted.

6. Requested Exemption We have requested an exemption from the-separation require-ment of Appendix R Section III.G.2.b for the Point Beach Nuclear Plant service water pump room in our October 26, 1983 letter.

Discussion The service water pump room is located in the circulating water pumphouse which is a separate fire area located approximately 70 feet east of the plant. The room boundaries are a full height combination of concrete, metal panel, and metal' grating. The room is divided by a 6-foot high barrier constructed of 1-hour rated cementitious panels. The room is provided with 4 photoelectric smoke detectors and an auto-matic wet pipe sprinkler system with redundant water supply piping. Hose lines and portable fire extinguishers are also available to provide manual fire suppression capability. The principal hazard is fuel oil for the diesel driven fire pump.

Fuel oil is stored in an approximately 250 gallon tank loca-ted within a diked area more than 30 feet remote from the room. Fuel oil supply piping to the diesel engine is buried within the floor. Safe shutdown equipment located in the room consists of 6 service water pumps. Three pumps are located on each side of the dividing barrier. The outermost pumps on each side of the barrier are separated by 26 feet.

The two outer pumps on each side of the barrier are separated by 16 feet. One service water pump is required to maintain safe hot shutdown of both units, and two pumps are required to achieve cold shutdown. Pump power cable is routed ir. the concrete floor. The diesel and electric motor driven fire pumps are also located on opposite sides of the barrier.

There are no intervening combustibles routed over the top of the barrier.

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Because power cables are routed in the concrete floor, the only exposed location of the service' water system in this fire area is at the service water pumps. Because two pumps are required to achieve cold shutdown, redundant pump sepa-ration can be less than 20 ft. However, we believe that equivalent separation is achieved by the 6-foot high barrier.

The response to item 3.5.1 of Enclosure 2 tx) Generic Letter 86-10 states that with the erection of a partial qualified 1-hour rated barrier for unprotected portions of circuits with less than 20 foot separation, if the fire area was protected'by automatic fire detection and suppression, com-pliance with Section III.G.2.b would be achieved. The ser-vice water pump room satisfies these conditions unless the barrier qualification is questioned. Section 4 of Enclosure 1 to~ Generic Letter 86-10 defines a fire area as an area sufficiently bounded to. withstand the hazards ass'ociated with' the area and, as necessary, tx) protect important equipment within the area from a fire outside of the area. Section 4 also states that in order to meet the regulation, fire area boundaries need not be completely sealed floor- to-ceiling, wall-to-wall boundaries. We interpret these conditions to be applicable to component separation barriers as well as fire area boundaries. The service water pump room divider wall is of sufficient height to prevent a fire ~from affecting service water pumps on both sides of the wall. A floor-to-ceiling barrier is not required because there are no intervening com-bustibles. On this basis, the divider' wall provides adequate separation to achieve compliance with Section III.G.2.b of Appendix R.

Therefore, the provision of additional service water pump separation would not serve the underlying purpose of the rule nor be necessary to achieve the underlying purpose of the rule and this exemption should be granted.

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