ML19325F341

LER 89-024-00:on 891013 & 30,unsealed Openings in Main Control Room Floor & Main Control Room West Wall Discovered. Caused by Wide Gap Between Structural Beam & Cable Tray. Openings Sealed & Fire Watch established.W/891113 Ltr

ML19325F341
Person / Time
Site:	LaSalle
Issue date:	11/13/1989
From:	Bucio G, Diederich G COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-89-024-01, LER-89-24-1, NUDOCS 8911200163
Download: ML19325F341 (5)

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, -b , Commonwealth Edloon 'l

, LaSall1 County Nuclear Station i N' <,- ' Rural Route #1, Box 220

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.- , Telephone 815/357 6761

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November'13, 1989 )

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Director of Nuclear Reactor Regulation U.S. Nuclear Regulatory Connission [

>: Mail station P1-137 4 Washington, D.C. 20555 j

Dear sir:

Licensee Event Report #89-024-00,. Docket 4050-313 is being  ;

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submitted to your office in accordance with ,

' 10CFR50.~13( a) ( 2) (i) .

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P jiederich '

(b/StationManager i LaSalle County station  ;

GJD/GB/bjp Enclosure xc :- Nuclear Licensing Administrator NRC Resident Inspector NRCfRegion III Administrator INPO - Records Center 1

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' I i 891120016389dhoh73 hDR- ADOCK 05 PDC i1 e w- .m., w , ,c--%,r, e A--,,. . - , , - , - , .,es.-ee. .--. ---=, - --. -

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LICENSEE EVENT REPORT (LER)

Docket Nu mer (2) Pane (3)

Facility Name (1)

W ile County Station unit 1 01 51 01 01 01 31 71 3 1 of!0l4 Title (4) errried Oneninos in Co'. trol " Due to Orialnal Contruction Other Facilities involved (8)

-Event Date (5) LER thaber (6) M srt Date (7)

Revision Month Day Year Facility Names Docket Numer(s)

Month Day Year Year / Sequential //

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// Nueer j///jj/ N@r LaSalle Unit 2 of 51 01 01 of 31 71 4 el 9

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01 0 111 11 3 81 9 01 51 01 01 01 l i 11 0 11 3 81 9 0 MM M THE REWEMENTS W 10CR OPERATING (Check one or siiers of the followino) (11)

MODE W 20.402(b) 20.405(c) 50.73(a)(2)(iv) ,,,,,,_ 73.7)(b) 5 , , _ ,,,,,,,

50.36(c)(1) 50.73(a)(2)(v) 73.71(c) poler 20.405(a)(1)(1) ,

50.36(c)(2) 50.73(a)(2)(vil) __,,other (Specify LEVEL 20.405(a)(1)(11) ,,,,_

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50.73(a)(2)(1) 50.73(a)(2)(viii)(A) in Abstract (10) 0i OI O ,_ 20.405(a)(1)(lii) .,X.

below and in 20.405(a)(1)(lv) 50.73(a)(2)(li) 50.73(a)(2)(vill)(B)

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/ /7/ //jj}'/jjj'/j'jj 20.405(a)(1)(v) 50.73(a)(2)(lii) ___ 50.73(a)(2)(x)

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LICENSEE CONTACT FOR THIS LER (12)

TELhPHONE NUPSER Name AREA CODE 8 l 1 15 31 51 71 -l 61 71 61 1 Gilardo Sucio. Technical Staff Enoineer. Extension 2445 COMPLETE ONE LINE FOR EACH Cummi FAILURE DESCRIBE 0 IN THIS REPORT (13) ___

CAUSE SYSTEM COMPONENT MANUFAC- REPORTA8LE CAUSE SYSTEM COMPONENT MANUFAC- REPORTABLE TURER TO NPRDS TURER TO WPROS l l l l l l l 1 l l B Kl P l l l N I I I 1 1 I I I I I I I I l

Expected Month l Day l Year SUPPLEMENTAL REPORT EXPECTED (14)

Submission  ;

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lyes (if ves. complete EXPECTED SUBMISSION DATE) 7lNO l ABSTRACT (Limit to 1400 spaces, i.e. approximately fifteen single-space typewritten lines) (16) on October 13, 1989 with Unit I defueled and Unit 2 in Cold Shutdown an unsealed opening in the main control room floor was discovered. Subsequently on October 30, 1989 with Unit 1 defueled and Unit 2 in operational condition 1 (Run) another unsealed opening in the main control ronn west wall was discovered. Based on a visual inspection of the openings and the fact that they were not intended penetrations, it was detennined that the openings had existed since the barriers were constructed, biork to seal these openings was quickly performed, in addition, smoke tests and visaal inspections of the entire control room floor, wall, and '

ceiling were perfonned to verify that no other openings which could conpromise the fire rating of the barriers existed, During this inspection, it was observed that a control room penetration had an excessive '

The reason for this was that the angle iron gap between a ventilation duct passing through it and the wall.

designed to seal this gap had moved away from the wall. A work request to repair the penetration was innediately written. No other deficiencies in the barrier were observed. This event is reportable pursuant to the requirements of 10CFR50.73(a)(2)(1) due to a devletion from the plant Technical Specifications.

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6 . .f' 1Lle" " E EVENT REPORT (LER) TEXT CONTINuAT10N' Fors kv 2.0 '

LIR r_ ; (6) Pane Cl)  ;

FACILITT NAfE (1) DOCKET NulGER (2)

Revision d

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Number

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'AllsCuawStationunit1 0 1 5 l 0 1 0 1 0 1 31 TI-3 819 '- 'Ol214 - 0 l' 0' '01 2 0F 01 '4 i

. . TEXT Energy Industry Identification System (Ells). codes are identified in the text as [XX]

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' PLANT AND SYSTEM IDENTIFICATION y

General Electric - Solling Water Reactor x

Energy Industry identification System.(Ells) codes are identified in the text as [XX).'

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. A. CONDITION PRIOR TO EVENT 1/2 Event Date: 10/13/89 . Event Time: 1500 Hours

' Unit (s):.  ;

i Reactor Mode (s): Defueled/4 Mode (s) Name: Defueled/ Cold Shutdown-Power Level (s): 05/05-4

8. DESCRIPTION OF EVENT On October 13, 1989, at 1500 hours0.0174 days <br />0.417 hours <br />0.00248 weeks <br />5.7075e-4 months <br />, with Unit 1 defueled and Unit 2 shutdown at 05 power, work

[' associated with modification M-1-1-87-03) was being performed in the' control room. This work involved smoke testing the electrical. floor penetration located underneath panet IPM13J prior to pulling the '

electrical cable running through the penetration. While the smoke test was being performed, an unsealed l} opening located underneath panel IPM13J was discovered. This ' opening comprumised the 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire rating on the floor.

-Similarly, on October 30, 1989, at 1800 hours0.0208 days <br />0.5 hours <br />0.00298 weeks <br />6.849e-4 months <br />, with Unit I defueled and Unit 2 in Condition 1 (Run) at 99.7% power a control room ventilation walkdown revealed a five inch diameter hole through.the west well I

of.the Main Control Room. This opening compromised the 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire rating of the wall. During a o

I' subsequent inspection of all control room fire barriers, a ventilation duct penetration located on the

'~ same wall was found to have an inadequate seal around the duct.

This event is reportable pursuant to he requirement of 10CFR50.73(a)(2)(l) due to a deviation from the plant Technical Specification.

C. APPARENT CAUSE OF EVENT This event resulted from the discovery of unsealed openings which conpromised the fire rating of two control room fire rated barriers. The first unsealed opening that was found was not an intended penetration. Rather, the opening was a result of a wide gap between a structural beam web surface and one end of a cable tray. It appeared that the section of a cable tray which runs horizontally between .

panels IPM13J and IPM15J terminated on one side due to a structural beam interfering with its path. At this intersection a wide gap between the beam and the cable tray was left unsealed, it is located at a concealed area and believed that this opening has existed since the barrier was construct *d.

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Fom Rev 2.0 L"C"""E EVENT REPORT (LER) TEXT CONTINUATION LER leBBER (6) Paae Cl)

' FACILITY N M (1) DOCKET IRNSER (2)

Year Sequential // Revision

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01214 01 0 01 3 01 4 h )1e ta -tv station unit 1 015101010131713 8I9 - - 0F TEXT Energy ladustry Identification System (Elis) codes are identified in the text as [XX]

C. APPARENT CAUSE OF EVENT (Continued)

The second opening, located on the west wall of the control room, was also determined.to be an unintendeo penetration. This was based on the fact that this penetration was not identified in any structural drawings and had no cables passing through it. Since there were no visible indications that this hole had ever been sealed it was concluded that this hole had existed since the barrier was ca structed.

A control room ventilation duct penetration located on the west wall of the room had an inadequate seal around the duct. The gap between the duct and the wall penetration was found unsealed because the angle Iron designed to seal this gap had been pushed away from the wall.

D. SAFETY ANALYSIS OF EVENT The safety consequences of this event are minimal because both of the affected fire barriers are-components of Fire Zone 4C1 (Main Control Room) which is continuously manned. Furthemore, each of the affected fire zones has a dedicated fire detection system. Therefore, the possibility that a fire in any of the affected zones would have spread into an adjacent zone through the unsealed openings before being detected is highly unilkely.

Control room pressurization was still acceptable in that the required pressure was maintained with these leakage paths existing.

l E. CORRECTIVE ACTIONS In accordance with the Action Statement of Technical Specification 3.7.6, LaSalle verified the

! operability of the fire datectors on at least one side of the inoperable assen61y and established an l hourly fire watch patrol. This fire watch will be maintained until all the openings are properly sealed.

The floor and wall openings were sealed per Work Requests L94057 and L64348 respectively within seven days of being identified. Work to seal the duct penetration is currently being perfomed per Wrk Request L94102. Action item Record 373-200-89-09901 will track conpletion of .this Work Request. In addition to initiating the necessary repair work, all control room walls, floor, and celling were visually inspected and smoke tested. Although fire barrier penetrations are not required to be l

i- airtight, the smoke test was performed to locate all gaps through the floor. A close visual inspection of these gaps was then performed to detemine their acceptability. No other unacceptable openings through these fire barriers were found.

F. PREVIOUS EVENTS l

LER Nunter Title 373/84-24-00 Electrical Cable Penetration Inoperable ,

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L1rsut88 EVENT REPORT (LER)' TEXT CONillRIATloW Fom Rev 2.0 '

I LER Mmmait (6) P< me (:l)

PACILITY leME (1) 00CKET NWWER (2)

Year / Sequential // Revision ,

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Lasa11e e-p=:v statten' unit 1 o'l 5 1 0 I o I C 1 31 71 3 e19 - o1214 - o l' o 01 4 'oF of 4

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Energy Industry identification System (Ells) codes are identified in the text as [XK]-

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G. Cofr0NENT FAILultE DATA i

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