ML18066A753

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Rev 2 to Evaluation of Effects of Fire on West Wall of Turbine Lube Oil Room Adjacent to Pipe Tunnel Between Turbine Bldg & Feedwater Purity Bldg
ML18066A753
Person / Time
Site: Palisades Entergy icon.png
Issue date: 06/14/1996
From: Young L
CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:
Shared Package
ML18066A752 List:
References
EA-FPP-95-054, EA-FPP-95-054-R02, EA-FPP-95-54, EA-FPP-95-54-R2, NUDOCS 9612170325
Download: ML18066A753 (14)
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Text

ATTACHMENT 2 CONSUMERS POWER COMPANY PALISADES PLANT DOCKET 50-255 Analysis of the Effects of a Fire on the West Wall of the Turbine Lube Oil Room Adjacent to the Pipe tunnel Between the Turbine Building and the Feedwater Purity Building I

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PALISADES NUCLEAR PLANT ENGINEERING ANALYSIS COVER SHEET EA-FPP-95-054 Title E~illUi!Iis;m Qf ttli: iiffi:saa Qf ii Eici: QO Ibl: l:ll:U ):ji!IL Qf Ibi: Iucbioi: LI.lb!: Qi! B!i2QID i1s;lii1s;1:0S IQ Ibl: ei1;11: Iuooi:I ai:Ij:jl:l:O**-~bi: c.

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INITIATION AND RBVIEW Calculation Status Preliminary Pending Final Superseded D

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Initiated I nit Review Method Technically Reviewed Revr Rev Appd Appd CPCo Description By Detail Qual By Appd Bv Date Alt Cale Review Test Bv Date 0

Original Issue LDYoung 12/12/95 DAC RWPhi lips 1/17/96 RLS PFB 1

Revised to "Final" based on LDYoung 3/23/96 DAC RWPhi lips 3/25/96 RLS JSE co11111ent resolution.

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2 Revised to delete fire modeling

~~/ln'J:1 6/9/96 information.

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r l.O OBJECTIVE The purpose of this Engineering Analysis is to show the impact of a fire on the West wall of the Turbine Lube Oil Room adjacent to the tunnel travelling between the Turbine Building (EL. 590'-0") and the Feedwater Purity Building. Specifically, the analysis will consider the equivalent fire resistance of the barriers, combustible loading within the rooms and suppression and detection. Through these considerations, this analysis will demonstrate the ability of the system as a whole to prevent a direct fire exposure hazard to safety related equipment or openings in other fire area barriers required to meet NRC guidelines.

2.0 ANALYSIS INPUT 2.1 Consumers Power Co. Palisades Nuclear Plant Drawings:

A-108, Rev. 1 F eedwater Purity Modification, Architectural, Pipe Gallery C-825, Rev. 2 Feedwater Purity Modification, Pipe Gallery, Foundation &

Floor Slab Plans - Area 8, 14 & lS M-216, Sh. 5 Rev. 3 Fire Protection, Reactor Building, Plan of EL. 590'-0" M-216, Sh.14 Rev. 5 Fire Protection, Turbine Building, Plan of EL. 590'-0" 2.2 National Fire Protection Association, Fire Protection Handbook, 17th Edition.

3.0 PALISADES NUCLEAR PLANT ANALYSIS CONTINUATION SHEET BA*

FPP-95-054 2.3 Palisades Nuclear Plant Engineering Analysis EA-FPP-95-11, Analysis of Combustible Loading for Fire Area 22, Turbine Lube Oil Room.

2. 4 Palisades Nuclear Plant Engineering Analysis EA-FPP-95-18, Analysis of Combustible Loading for Fire Area 230, Turbine Building - General.

2.5 Palisades Nuclear Plant Fire Hazards Analysis, Revision 2, February 1, 1989.

2.6 Palisades Nuclear Plant Fire Protection Program Report (FPPR), Volume 2, Section VUI; List of Changes to Appendix A to Branch Technical Position APCSB 9.5-1 and Regulatory Guide 1.78 and 1.101, Revision 1, October. 26, 1989.

2.7 Palisades Nuclear Plant Fire Protection Program Report (FPPR), Volume 3,Section IX, #46.

2.8 U.S. Nuclear Regulatory Commission (NRC) Generic Letter 86-10, Implementation of Fire Protection Requirements, April 24, 1986.

2. 9 NRC Standard Review Plan NUREG-0800, BTP CMEB 9. 5-1, Guidelines for Fire Protection for Nuclear Power Plants, Revision 2, July 1981.

2.10 Methods of Quantitative Fire Hazard Analysis, EPRI Research Project 3000-37, by F.W. Mowrer, dated May 1992.

2.11 Palisades Nuclear Plant Engineering Analysis EA-APR-95-001, Appendix R Safe Shutdown Equipment List and Logic Diagrams.

2.12 Palisades Nuclear Plant Engineering Analysis EA-FPP-96-012, System Hydraulic Analysis for the Lube Oil Storage Room.

2.13 Palisades Nuclear Plant Engineering Analysis EA-FPP-96-013, System Hydraulic Analysis for the M-18 Area.

2.14 National Fire Protection Association, Automatic Sprinkler Systems Handbook, 6th Edition.

2.15 Palisades Nuclear Plant Engineering Analysis, EA-APR-95-007, Rev. 0, 1 OCFR50, Appendix R Safe Shutdown Analysis.

ASSUMPTIONS None Sheet _z_' Rev # _2 __

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  • PALISADES NUCLEAR PLANT ANALYSIS CONTINUATION SHEET 4.0 ANALYSIS 4.1 General General Guidelines for Plant Protection are discussed in the List of Changes and Response to Appendix A to BTP APCSB 9.5-1 and Regulatory Guide 1.78 and 1.101, Subsection D.1.j. The regulatory position states that concerning compartmentation "... Floors, walls and ceilings enclosing separate fire areas should have minimum fire rating of three hours." It then goes on: to state that "... The fire hazard in each area should be evaluated to determine barrier requirements." Also,... "If barrier fire resistance cannot be made adequate, fire detection and suppression should be provided... "

Based upon the above statements, it is apparent that the analysis of a specific barrier for acceptability should subsequently follow this order of importance:

a. The capability of the barrier must satisfy the minimum fire rating guideli11e of 3-hours. If not then;
b. The barrier must be adequate to withstand the actual combustible loading in the fire areas separat"ed by the barrier. If not then;*
c. The actual configuration must be reviewed in order to take credit for other systems or circumstances that may increase the acceptability of the barrier (e.g. suppression, detection, etc... ).

This analysis is based upon the above three criteria. It shall be used to demonstrate the capability of the fire barrier and its supporting systems to adequately prevent the spread of fire through the pipe tunnel separating the Feedwater Purit)' Building and the Turbine Building (EL. 590'-0").

Additional regulatory guidance is provided in NUREG 0800, Section 9.5.1, sub-section C.7.h, "Turbine Building," which states, in part:

The turbine building should be separated from adjacent structures containing safety-related equipment by a fire barrier with a minimum rating of 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />.... Openings and penetrations in the fire barrier should be minimized and should not be located where the turbine lube oil or generator hydrogen cooling system creates a direct fire exposure hazard to the barrier. Considering the severity of the fire hazards, defense in depth may dictate additional protection to ensure barrier integrity.

In summary, the regulatory goal of the Turbine Lube Oil Room walls is to prevent a direct exposure fire hazard to either safety related equipment or openings and penetrations in fire barriers containing safety related equipment.

BA-FPP-95-054 Sheet _l_ Rev # _.._2 __

Reference 2.6, Page 27 Reference 2.9

PALISADES NUCLEAR PLANT ANALYSIS CONTINUATION SHEET EA-FPP-95-054 4.2 Description of the Fire Barrier The West wall of the Turbine Lube Oil Room is corrugated sheet metal directly connected to building support steel. The remaining walls are concrete block walls. The ceiling is approximately 8" thick reinforced concrete, based on field

  • measurement, and the floor is reinforced concrete resting on the grade elevation. The two doors in the south wall are thre~-hour rated doors. There are two openings in the ceiling for equipment access. These openings are protected by concrete plugs the same thickness as the ceiling with metal framing. The room is curbed to contain potential oil spills or a single tank rupture within the room.

The Turbine Lube Oil Room is a free standing room within the main Turbine Building. Figure #1 shows a plan view of the area. This room does not provide structural support for the Turbine Building. However, the lower portion of two columns supporting the Turbine Building are located within.the Turbine Lube Oil Room walls near the west end. Also, the concrete slab ceiling of the room is supported by structural steel beams. Neither the Turbine Building structural steel nor the ceiling beams are protected with fireproofing materials. The size of the columns and beams and connecting steel outside the room, provide a large heat sink, and in conjunction with the automatic sprinkler system ensure these components will not fail prior to the arrival of additional fire fighting equipment to further suppress a fire in this area (See Section 4.4 for further discussion).

Sheet ___j_;_ Rev # __._2 __

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PALISADES NUCLEAR PLANT ANALYSIS CONTINUATION SHEET EA-FPP-95-054 Figure #1 - Plan View 590' Elev. of Turbine Building Not To Scale Feedwater Purity Bldg.

t I Outside Area Open End Shops/Labs/Offices Openings Near Ceiling of Pipe Tunnel C<::N Pump RoomWaO

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Turbine/Condenser Area CV-05228 Turbine Building

1.

t North Figure #2 is an elevation view of the west wall of the Turbine Lube Oil Room.

An opening approximately nine inches wide running the width of the wall is located about 15 ft. high on the 21 ft. high wall, where the ceiling supports for

  • the Feedwater Purity Tunnel were added. This provides a direct air flow path from the Turbine Lube Oil Room to just below the ceiling area of the Feedwater Purity Building. In addition, various piping penetrations are made in the west wall that are not sealed around the annular spaces. The upper 5 to 6 ft. of the Turbine Lube Oil west wall is above the Feedwater Purity Tunnel ceiling and is exposed to the outside plant area.

Sheet --2..,_ Rev # _2 __

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Opening Figure #2 - Elev. View of Turbine Lube Oil West Wall Not To Scale outsidf Area Between..------1 Rooms

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I Tunn I Area 590' Elev. Front View Facing East Side View Facing North The F eedwater Purity Tunnel connects the separate F eedwater Purity Building to. the Turbine Building and is over ISO ft. long. A portion of this tunnel runs adjacent to the lower portion of the Turbine Lube Oil Room west wall. The tunnel is constructed of structural steel with a corrugated

  • sheet metal wall and ceiling containing fiberglass insulation between the inner and outer sheet metal walls. The structure has no listed fire resistance rating and would be expected to fail if exposed to fire conditions.

The Turbine Building wall adjacent to the Feedwater Purity Tunnel is sheet metal supported on structural steel, similar to the Turbine Lube Oil west wall.

There are numerous openings in the east wall of the F eedwater Purity Tunnel adjacent to the Turbine Building and the south end of the tunnel opens directly

. into the Turbine Building.

Reference 2.1

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MW.ors...-as PALISADES NUCLEAR PLANT ANALYSIS CONTINUATION SHEET 4.3 Description of Combustible Loading

a.

F eedwater Purity Pipe Tunnel The pipe tunnel contains two condensate pipes, a fuel oil transfer pipe (welded fittings near Turbine Lube Oil Room}, four lightly loaded cable trays, and other minor electrical and mechanical items.

The electrical cables in the cable trays enter conduits approximately 20 ft. from the south end of the tunnel opening into the 590' elevation of the Turbine Building. There are no significant combustible materials that traverse the openings from the Feedwater Purity Tunnel into the Turbine Building. The Feedwater Purity Tunnel contains no safety related equipment or circuits and has minimal combustible loading, so it is not classified as a separate fire area.

b. Turbine Building (General Area@ EL. 590'-0") North & West Side Combustible loading in the Turbine Building general area at EL.

590'-0" is approximately 15 minutes. This fire loading is spread over three elevations of the Turbine Building.

Equipment such as a heater drain cooler, feedwater heater, and air ejector are located near the east and south openings to the pipe tunnel. Any cable in this area is enclosed in conduit. Based on plant walkdowns, there are no significant combustibles within a radius of 20 ft. from the various openings of the Feedwater Purity Tunnel into the 590' elevation of the Turbine Building. Waste oil tanks (T-130 and M-18) are located to the west of the Feedwater Purity Tunnel south opening. These tanks are positioned just outside of the 20 ft. distance from the Feedwater Purity Tunnel, and are protected by a wet pipe sprinkler system with a spray density greater than 0.30 gpm/ft2.

The next level above the 590'-0" elevation, in this area of the Turbine Building, is the 607'-6" elevation. This floor level is metal grating, which is not a confining space for smoke or heat. Therefore, any smoke or heat generated from combustibles on the 590' elevation would rise, not affecting the pipe tunnel, its contents, or the Feedwater Purity Building. This area is also connected to the turbine operating floor above by open stairwells and various large openings with metal open grating coverings that provide an even larger vent area for any smoke and hot gases and minimize heat buildup on the 590' elevation.

Transient combustibles are administratively controlled in all plant areas by plant procedure. Transients brought into this area of the Turbine EA-FPP-95-054 Sheet _L_ Rev # __._2 __

Reference 2.11 Reference 2.4 Reference 2.1 Reference 2. 13

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M<<lmA#'S N88tlU PALISADES NUCLEAR PLANT ANALYSIS CONTINUATION SHEET Building for maintenance and operating activities, would be expected to be minimal based upon the type of equipment located in the area.

c.

Turbine Lube Oil Room The fire loading in the Turbine Lube Oil Room (Fire Area 22),

results in an Equivalent Fire Severity of "greater than 9 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br />" and therefore has a VERY HIGH Fire Loading Classification. A significant fire in this area would initially be ventilation limited due to the limited size of room openings and could not achieve the temperatures normally projected for an open combustible liquid pool fire.

The only significant openings to allow combustion air into the room are through the west wall to the Feedwater Purity Tunnel. This opening is located at the ceiling level of the Feedwater Purity Tunnel and runs the length of the west wall as shown in Figure #2. It is less than one-foot wide. The remaining ventilation openings into the room are protected by fire dampers which, due to their location. near the ceiling, close early in the event and would not provide additional combustion air. If the full area automatic sprinkler sy~tem failed, then the sheet metal west wall would be expected to fail and provide additional combustion air, otherwise, the fire size would be greatly limited by the small amount of combustion air available. If the sheet metal west wall did fail, then the

. F eedwater Purity Tunnel wall would be expect to fail as well venting

  • the smoke and hot g~ses to the outside.
d. Feedwater Purity Building The Feedwater Purity Building is over 150 ft. from the Turbine Lube Oil Room west wall and the Turbine Building. Some electrical cables in cable tray traverse the distance separating these buildings inside the Feedwater Purity Pipe Tunnel. The Boiler Room in the Feedwater Purity Building is protected by a sprinkler system. The Feedwater Purity Building and connecting tunnel do not contain safety related equipment. No combustible loading calculation was performed for this building due to the large separation from the Turbine Building or any safety related structures or components.

BA-FPP-95-054

. Sheet _a._ Rev # ~2 __

Reference 2.3 Reference 2. i' Reference 2.11

PALISADES NUCLEAR.PLANT ANALYSIS CONTINUATION SHEET 4.4 Description of Suppression and Detection

a.

Suppression The Turbine Lube Oil Room is equipped with full area automatic wet pipe suppression system. Sprinkler hydraulic analysis shows the spray density is 0.55 gpm/3,000 sq. ft. which exceeds the 0.30 gpm/3,000 sq. ft. design specified for Extra Hazard (Group 1) protection.* The extra water spray density will greatly reduce the peak room temperatures.

Manual suppression is provided by a hose station located less than 20 ft. away from the Turbine Building entrance to the pipe tunnel at the 590'-0" elevation. Various other hose stations are located throughout the Turbine Building on this and other elevations to provide backup fire fighting capability. Fire fighting foam equipment is located just outside the Turbine Lube Oil Room on the 590'-0" elevation.

The Turbine Building has partial area automatic wet pipe suppression systems located in areas around the Turbine Lube Oil Room. These systems provide protection for areas with cable trays, lube oil, hydraulic oil reseivoirs and office areas on both the 590'-0" elevation and the 607'-6" elevation. The Turbine Building areas to the north, south and east of the Turbine Lube Oil Room are protected by these sprinkler systems. Portions of these systems are located between the Turbine

  • Lube Oil Room and the Component Cooling Water (CCW) Pump Room wall located east of the Turbine Lube Oil Room. The CCW Pump Room wall, which contains non-fire rated openings, provides separation of safety related equipment from the Turbine Building.
b. Detection There is no automatic detection located in the general Turbine Building area near the access door to the pipe gallery (EL. 590'-0"). However, the automatic sprinkler systems in both the Turbine Lube Oil Room and the Turbine Building are equipped with flow alarms. These alarms will provide notification to the continuously manned Control Room to ensure prompt fire brigade response.
c. Fire Brigade/Equipment The plant fire brigade training program includes actual involvement with fighting flammable liquid fires during the live fire training. This training involves using manual hose streams to push back the flames and then entering the flammable liquid pool to shut off a flammable gas valve that is adding fuel to the flammable liquid fire. The 590'-0" EA*

FPP-95-054 Sheet _J_ Rev #.-2 __

Reference 2.12 Ref. 2.14, Fig. 1.24

PALISADES NUCLEAR PLANT ANALYSIS CONTINUATION SHEET elevation of the Turbine Building contains one of the fire brigade depot areas for equipment storage providing ready access to equipment for a fire in this area. Equipment such as self-contained vent fans capable of delivering 16,000 CFM are also located outside the Turbine Lube Oil Room. A wheeled dry chemical type BC rated fire extinguisher is also located nearby in the Turbine Building. As mentioned above, the area

    • also contains fire fighting foam equipment for a potential lube oil fire.

4.5 Post-Fire Safe Shutdown Equipment The Turbine Lube Oil Room and F eedwater Purity Building Pipe Tunnel do not contain any post-fire safe shutdown equipment or circuits. The Turbine Building has been analyzed for a loss of all equipment and circuits in this area to ensure that post-fire safe shutdown can be safely achieved from the Control Room or other fire area locations separate from the

  • Turbine Building and by definition the Turbine Lube Oil Room. Therefore, *
  • if a serious fire were to spread between the Turbine Lube Oil Room, Feedwater Purity Building Pipe Tunnel and the Turbine Building it would result in the same consequences as a Turbine Building fire alone and would not adversely impact the existing ability of the plant to safely shutdown.

The Turbine Building safe shutdown component that is located closest to the Feedwater Purity Pipe Tunnel openings into the Turbine Building is an auxiliary feedwater steam supply valve CV~0522B, shown in Figure #1, above.

This valve is located behind a large feedwater heater and heater drain cooler that essentially provides a radiant energy shield from the openings in the Feedwater Purity Pipe Tunnel that are over 20 feet away with no intervening combustible materials. This valve is located just above the floor on the 590'-0" elevation and would not be subject to smoke and hot gases exiting from the tunnel openings, due to the volume and height of the Turbine Building. No line of sight openings exist between the Turbine Lube Oil Room and this component, ensuring that a fire in the Turbine Lube Oil Room could not provide a direct exposure fire hazard to this safe shutdown component.

4.6 Overview of Fire Barrier Adequacy The primary scenario for this area is the spread of a fire from the Turbine Lube

  • Oil Room into the Turbine Building that may ultimately affect either safety related equipment in the Turbine Building or openings in walls separating the Turbine Building from safety related plant areas such as the CCW Pump Room. Each issue is addressed separately in the discussion below. There is minimal concern for the spread of fire from the Turbine Building back into the Turbine Lube Oil Room due to the low combustible loading on the Turbine Building side.

EA-FPP-95-054 Sheet ___lQ_ Rev #* _..-2 __

Reference 2.11 Reference 2.15

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  • PALISADES NUCLEAR PLANT ANALYSIS CONTINUATION SHEET BA*

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From the descriptions provided above there are several defense-in-depth barriers to prevent the spread of fire from the Turbine Lube Oil Room back into the Turbine Building. These can be summarized as follows:

The Turbine Lube Oil Room has full area automatic suppression that is

~ydraulically analyzed to exceed the design standards. In addition, curbing is provided to contain potential oil spills within the room.

  • The non-fire rated west wall is exposed to the exterior for the upper 5 to 6 feet and if wall failure did occur due to a fire, then this area would be expected to fail first venting the smoke and hot gases outside the Turbine Building area. Additionally, the sheet metal Feedwater Purity Tunnel wall
  • would be expected to fail quickly, if the lower Turbine Lube Oil Room west wall did fail and expose the tunnel to fire conditions, again venting the smoke and hot gases to the outside area.
  • The size of the realistic fire in the Turbine Lube Oil Room would be ventilation limited due to limited openings into the room and would not reach the temperatures normally expected in a combustible liquid pool fire prior to sprinkler system actuation which would then limit fire growth even further.
  • Any smoke and hot gases vented into the Feedwater Purity Tunnel and Turbine Building would ultimately disperse over the entire Turbine Building area and* minimize heat stress on nearby equipment. The areas within 20 ft. of the Feedwater Purity Tunnel opening on the 590' elevation into the Turbine Building are virtually devoid of combustible material and contain no safety related or safe shutdown equipment.
  • The water flow alarms for the automatic sprinkler syste.ms located in the Turbine Lube Oil Room and Turbine Building would alarm in the Control Room and initiate fire brigade response.
  • An on-site five-man fire brigade that is specifically trained in fighting flammable liquid pool fires is available to respond at any time and has equipment such as nearby hose stations, foam carts, wheeled dry chemical extinguisher specifically suited for lube oil fires available in the area of concern.
  • These areas are routinely patrolled by armed security personnel and operations personnel, which are predominately ma:de up of personnel trained for staffing the fire brigade, improving the likelihood of early fire detecti.on.
  • Additional defense-in-depth fire barrier protection will be added in the future by replacing the Turbine Lube Oil Room west wall, below the

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PALISADES NUCLEAR PLANT ANALYSIS CONTINUATION SHEET EA-FPP-95-054 F eedwater Purity Tunnel ceiling elevation, with a fire rated wall as committed to the NRC in a Consumers Power Company letter dated April 1, 1996.

The remaining concern is for direct fire exposure to openings in walls separating safety related equipment from the Turbine Building. The west wall of the CCW Pump Room contains various openings into the Turbine Building and these are described in a separate evaluation. However, the additional defense-in-depth features, from those described above, that protect the CCW openings are a follows:

The areas within 20 ft. of these openings on the Turbine Building side are almost devoid of combustible materials. Floor drains are located throughout the Turbine Building to prevent the spread ofliquid pool fires to the area adjacent to these openings on the 590' elevation.

Automatic wet pipe suppression systems are located in the Turbine Building such that a fire on the west side of the Turbine Building (near the Turbine Lub_e Oil area) would have to cross these protected ateas before exposure of the openings could occur.

The Turbine Building and the CCW Pump Room are evaluated as separate fire areas in the Appendix R analysis. However, since the west wall of the

  • Turbine Lube Oil Room is facing opposite and over 100' away from the unrated openings in the CCW Pump Room wall, no direct fire exposure hazard is considered credible. In addition, the Turbine Building area for 20' away from the Turbine Lube Oil Room contains no intervening combustibles.

5.0 CONCLUSION

The regulatory goal of the Turbine Lube Oil Room walls is to prevent a direct exposure fire hazard to either safety related equipment or openings and

  • penetrations in tire barriers containing safety related equipment. The plant configuration described above provides defense-in-depth such that the system.

as a whole prevents a direct fire exposure hazard to safety related equipment or openings in other fire area barriers required to meet NRC guidelines.

Sheet -1Z._ Rev # __.,_2 __

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Pages 13 th'rough 17 intentionally omitted

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