05000277/LER-1981-034, Forwards LER 81-034/01T-0.Detailed Event Analysis Also Submitted

Forwards LER 81-034/01T-0.Detailed Event Analysis Also Submitted

ML20005B096
Person / Time
Site:	Peach Bottom
Issue date:	06/26/1981
From:	Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20005B097	List: 05000277/LER-1981-034, Forwards LER 81-034/01T-0.Detailed Event Analysis Also Submitted 05000277/LER-1981-034-01, /01T-0:on 810612,four Cables Found to Be Designated Nonsafeguard & Routed Such That Partial Separation Provided.Caused by Incorrect Plant Design.Design Change Made
References
NUDOCS 8107060307
Download: ML20005B096 (3)

LER-1981-034, Forwards LER 81-034/01T-0.Detailed Event Analysis Also Submitted

Event date:
Report date:
2771981034R00 - NRC Website

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PHILADELPHIA ELECTRIC COMPANY j

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23O1 MARKET STREET' y' < ' -

3 !i P.O. BOX 8699 dlD R/

100i -1001 PHILADELPHIA. PA.19101 (21518414000

'f June 26, 1981 Mr. Boyce H. Grier, Director Office of Inspection and Enforcement Region ~I US Nuclear Regulatory Commission 631 Park Avenue l

King of Prussia, PA 19406

Dear Mr. Grier:

SUBJECT: Licensee Evrnt Report Narrative Description The following occurrence was reported to Mr. Blough, Region I, United States Nuclear Regulatory Commission on June 12, 1981.

Reference:

Docket Nos. 50-277 50-2.3 Report No.:

LER 2-81-34/1T-0 Report Date:

June 26, 1981 Occurrence Date:

June 12, 1981 Facility:

Peach Bottom Atomic Power Station RD #1, Delta, PA 17314 T_echnical Specification Reference:

Technical Specification 6.9.2.a.(9) requires prompt reporting of " Performance of structures, systems, or components that requires remedial action or corrective measures to prevent operation in a manner less conservative than assumed in the accident analyses in the safety analysis report or technical specifications bases; or discovery during plant life of conditions not specifically considered in the safety analysin report oc technical specifications that require remedial action or corrective measures to prevent the existence or development of an unsafe conditi~on."

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' 8107060307 810 EiY gj /

PDR ADOCy 0500 7

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Mr. ' Boyce 11. Grier Page 2 Description of the Event:

During design review of cable routing initiated as a result of an investigation with. respect to fire protection, it was found that four safeguards power supply cables for RHR, core spray, HPCI, and RCIC pump room cooler fan auxiliary control relay cabinets on both units had been designated as non-safeguard during original design, and therefore not fully routed as safeguard cables.

The four cables for each unit supply control power r3 four cabinets containing the relays for the automatic start u 2ture of the room cooler fans for the above systems.

The

'A' cable supplies power for control of RCIC and

'A' RHR and core spray pump room coolers.

The

'B' cable supplies power for control of HPCI and

'B' RHR and core spray pump room coolers.

The

'C' and

'D' cables supply power for control

'C' and

'D' Ri!R and core spray pump room coolers respectively.

The cables to the A,

C, and D cabinets are routed separately.

However, the

'D' cable is routed partially with the

'A' cable in Unit 2, and with the~'A' cable and

'D' cable (at different points) in Unit 3.

Probable Consequences of the Occurrence:

In the event of a fire in the cable tray containing both A and B cables,~ auto start of the HPCI,RCIC, and A and B core spray and PMR pump room coolers may not occur.

However,_ manual operation of the room coolers would still be possible from the local control stations.

In the event of a fire in the cable tray containing 3B and 3D cables, auto start of the RCIC and 3B and 3D core spray and RHR pump room coolers may not occur.

Again, local manual operation of the room coolers would still be possible.

Cause of the Event

i During the design phase of the Peach Bottom Units 2 and 3, the room cooler fan auxiliary control relay cabinet power supply cables were incorrectly considered to be non-safeguard and as a 1

result not all portions of the cables were routed separately as are safeguard cables.

Corrective Actions

i' The

'B' RHR and core spray pump-and HPCI room coolers are being operated continuously in the manual mode.

Thus loss of one

=!

cable tray ucchion will result in loss of automatic capabilities I

Mr. Boyce II. Grier Page 3 e

of at most one ECCS room cooling system channel.

Concurrently, Engineering Design changes will be made to correct the routing deficiencies and the cables rerouted as soon as possible.

Very truly yours, b

./ lb {,4 /

l Cooney

[

Superintendent Generation Division - Nuclear Director, NRC - Office of Inspection and Enforcement cc:

Mr. Norman M. Haller, NRC - Office of Management &

Program Analysis