ML19262A080

Forwards Summary Decription of Minor Design Change 79-012 Re Automatic Wet Pipe Sprinkler Protection

ML19262A080
Person / Time
Site:	Cooper
Issue date:	10/19/1979
From:	Pilant J NEBRASKA PUBLIC POWER DISTRICT
To:	Ippolito T Office of Nuclear Reactor Regulation
References
NUDOCS 7910260312
Download: ML19262A080 (5)

Text

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GENERAL OFFICE P. o. Box 499 CoLUMSUS, NEBR ASKA 68601 Nebraska Publ.ic Power Distr.ic t. ___

rete ~o~E i4m64..s6 October 19, 1979 Director, Nuclear Reactor Regulation Attention: Mr. Thomas A. Ippolito, Chief Operating Reactors Branch No. 3 Division of Operating Reactors U.S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

Fire Protection Modifications Cooper Nuclear Station NRC Docket No. 50-298, DPR-46

Dear Mr. Ippolito:

The Fire Protection Safety Evaluation Report (SER) for Cooper Nuclear Station, issued May 23, 1979, requested that Nebraska Public Power District provide design information relating to specific fire protection modifications. In response to this request, enclosed is the summary description of the following design change:

Minor Design Change No.79-012 Automatic Wet Pipe Sprinkler Protection for Reactor Building MG Set Heat Exchangers, Cable Expansion Room, Laundry Room and adjacent corridor and the Instrument Storage Room in the Control Building (corresponds to SER section 3.0, items 3.7, 3.12, and 3.19).

Since the complete design change package contains detailed information not included in the enclosed summary, and since this information is of special interest only to the actual staff reviewers, two copies of the complete design change package are being forwarded to Mr. Robert T. Dodds, Nuclear Regulatory Commission, Region V. The complete design change package is also available at Cooper Nuclear Station for review.

The Staff's prompt notification of any comments, or lack of comments, regarding the enclosed modification will be most helpful in meeting the implementation schedule established in the SER. If no response is received from the Staff within the specified 90 day period, the District will proceed with implementation of the modifications as \

described. 'k i216 326 7910260 312'_ _

Thomas A. Ippolito October 19, 1979 Page 2 Pursuant to SER item 3.15.2, " Control Room-Particle Board Wall," the CNS Control Room particle board wall paneling was tested by Southwest Research Institute in accordance with ANSI / ASTM E 84-77a with the following results:

Flame Spread 80 Fuel Contributed 65 Smoke Developed 635 The Flame Spread and Fuel Contributed ratings indicate that a fire involving the CNS Control Room wall paneling would not spread at such a rate as to exceed the capability of the existing manual fire fighting equipment in the areas, i.e., fire hose station, portable Class "A" fire extinguishers. The CNS Control Room is constantly manned and is equipped with automatic product-of-co:tbustion detectors which would readily detect a fire involving the Control Room wall paneling. Even though the Smoke Developed rating is higher than the other two ratings, the development of smoke only makes a wall paneling fire easier to detect.

It is the District's position that the CNS Control Room wall paneling and the fire test ratings established for it are acceptable.

If you have any questions or require additional information, please do not hesitate to contact me.

Sincerely,

=f

. Pilant Director of Licensing and Quality Assurance JDW/cmk Enclosure cc: Mr. Robert T. Dodds U.S. Nuclear Regulatory Commission, Region V Office of Inspection and Enforcement 1990 California Boulevard, Suite 202 Walnut Creek, CA 94596 1216 3

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SUMMARY

OF MDC 79-12 AUTOMATIC WET PIPE SPRINKLER PROTECTION FOR REACTOR BUILDING MG SET HEAT EXCHANGERS, CABLE E:GANSION RCOM, LAUNDRY ROOM AND ADJACENT CORRIDOR AND THE INSTRUMENT STORAGE ROOM IN THE CONTROL BUILDING I. DESCRIPTION This MDC is initiated to provide autc=atic wet pipe sprinkler systecs to the folleving areas:

1. MO set oil heat exchangors in the Reactor Building - ficor eleva-tion 931'-6", bounded by colu=n lines P&Q and 10.5 & 12.7.

2. Cable Expansion Room in the Control Building - floor elevation 918'-0", bounded by column lines J.8 & H.8 and 12.9 & 13.8.

3. Laundry Room and adjacent corridor in the Control Building -

floor ele'vatica 903'-6", bounded by col" lines K.1 & E.8 and 12.9 & 13.8.

4. Instrument Storage Room in the Control Building - floor elevation 903'-6", bounded by colu=n lines J.8 and 16.2 & 17.

Currently, no automatic fire protection system is insta). led in any of the above listed areas.

, II. JUSTIFICATION

1. MG Set Oil Heat Exchancers This arec bounded by column lines P & Q and 10.5 & 12.7 at elevation 931'-0" in the Reactor Building contains MG set lA and 13 oil heat exchang-ers. West of the oil heat exchangers at column line Q there is a pipe chase used to convey safety-related electrical circuits. Reliance on the existing drain system to re=ove a fire hacard oil spill is not considered -

adequate. A fire due to oil spillage could cause loss of all MG set oil heat exchangers and some safety-related electrical circuits in the Reactor Building. Therefore, the oil heat exchangers for MG sets lA

& 13 should be protected by an automatic wet pipe sprinkler systen.

This condition was reported to the Nuclear Regulatory Co=missica (NRC) on page F-1 of the " Fire Protection Review to Appendix A to Branch Technical Position APCSB 9.5-1" which was transmitted on December 17, 1976. On October 10 through 13, 1978, an NP.C staff fire protection review team visited ths Cooper Nuclear Station (CNS) and recommended the installation of an aute=atic suppression system. On December 11, 1978, Nebraska Public Power District (NPPD) cc=mitted to the NRC request. Caletlation sheets for pipe support design analysis, water drain systen analysis, and the number of wet pipe sprinkler heads are included in the complete design package.

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2. Cable Expansion Room The Cable Expansion Room contains Class I, Division 1 and Class I, Division 2 safety-related electrical circuits. If a fire were to happen in this room, it could cause an unacceptrble loss to both Class I, Division 1 and Class I, Division 2 electrical c!.cuits. Therefore, the Cable Expansion Room should be protected by an automatic vet pipe sprinkler system. On October 10 through 13, 1978, an NRC staff fire protection review team visited CNS and recommended the installation of an automatic suppression system. On December 11, 1978, Nebraska Public Power District committed to a system suitable to the NRC. In a meeting held at CNS on November 29, 1978, Stone & Webster was instructed by CNS to provide an automatic suppression system design. Calculation sheets for pipe support design analysis, the number of wet pipe sprinkler heads and hydraulic calculations are included in the compigte design change package.

3. Laundry Room and Adjacent Corridor Launderable protective clothing is placed in a plastic bag and sent to the Laundry Room for cleaning. The corridor adjacent to the Laundry Room is bounded by column lines J.4 & H.8 and 12.9 & 12.7 and is used for storing the plastic bags filled with items to be cleaned. The protective clothing and plastic bags are flammable materials and if a fire were to happen in the Laundry Room and corridor, the potential exists for the fire to spread to the Cabla Expansion Reom and other areas which could cause an unacceptable loss of safety-related electrical circuits. Therefore, to prevent this situation, the Laundry Room and adjacent corridor should be protected by an automatic wet pipe sprinkler system. On October 10 through 13, 1978, an NRC staff fire protection review team visited CNS and recommended the installation of an automatic suppression system or a 3-hour fire barrier between the Cable Expansion Room and all other areas. On December 11, 1978, Nebraska Public power District committed to an automatic fire suppression system. The design analysis for pipe hangers and calculation sheets for the number of sprinkler heads required in these areas are included in the complete design change package.

4. Instrument Storage Room High precision instruments and spare parts contained in paper boxes are stored in this room. The instrument boxes are made of combustible materials and if a fire were to occur in the Instrument Storage Room, the possibility exiscs for the fire to spread to the corridor and adjacent 125/250 VDC static inverter and battery rooms at elevation 903'-6" in the Control Building. This corridor and adjacent rooms contain redundant DC safety-related electrical circuits, and a fire in this area could cause an unacceptable loss of redunaant electrical circuits. Therefore, the Instrunent Storage Room should be provided with. an automatic wet pipe sprinkler system. On October 10 through 13, 1978, an NRC staff fire protection review team visited CNS and recommenatd the installation of an automatic sprinkler system. On December ll,1978, Nebraska Public Power District committed to either an automatic sprinkler system or as an alternate, installing a 3-hour rated fire door in the room and providing one and one-ha1f hour rated duct dampers in all ducts through the room walls.

1216 329 In a meeting held at CSS on November 29, 1978, Stone & Webster was instructed by CNS to provide an automatic suppression system design. The design analysis for pipe supports and calculation sheets for: the number of sprinkler heads required in the Instrument Storage Room are included in the complete design change package.

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