ML20079G022
| ML20079G022 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 09/27/1991 |
| From: | Helwig D PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9110080372 | |
| Download: ML20079G022 (2) | |
Text
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4 PillLADELPilIA ELFCTRIC COMPANY NUCl. EAR GROUP llEADQUARTERS 955-65 CilESTERBROOK BIND.
WAYNE, PA 19087-5691 September 27, 1991 (215) 640 6654 Docket Nos. 50-277 50-278 DAVID R. HELWIG VICE PRESIOCNT NLClLAR CNGINEERN3 & SERVCES LLcense Nos. DPR-44 DPR r,s s
U.S. Nuclear Regulatory Commission Attna Document Control Desk Washington, DC 20555
Subject:
Peach Bottom Atomic Power Station, Units 2 and 3 Follow-up Actions Related to Cable Insulation Failures Dear Sir On August 8, 1991, representatives from Philadelphia Electric Company and the NRC met to discuss recent cable insulation failures at Peach Bottom Atomic Power Station (PBAPS), Units 2 and 3.
Our presentation included a discussion of recent failures, an explanation of the failure mechanism " treeing," a brief description of a power system improvemant modification and our plans fcr additional cable inspection. The purpose of this letter is to provide updated information regarding our plans for additional inanection.
At the-meeting, we indicated that during the upcoming Unit 3 refueling octage we would inspect two cab M runs of com;> arable failure potential, one Residual Heat Removal (RHR) motor cable and one liigh Pressure Service Water-(HPSW) cable.
During our discussions, the NRC suggested that we_ inspect a cable of the lighest safety significance, regardless of our estimate of itc likeliheiod *o fail.
In response to this suggestion, PECo committed to re-evaluate the selection of cables to be examined.
As a result of this re-evaluation, we have modified the plan for cable sampling te.ubstitute s cable of high safety *1gnificance in place of the RHR cabla yreviously planned.
It is our assessment that since both-the HPSW anw PIR cables are equivalent with respect to the factors that influence the. formation of trees, either is technically acceptable and will provide sufficient data for evaluation.
The inclusion of a cau a of high safety-significance and low likelihood of failure will validate our assessment of the full range of failure potential.
We are currently evaluating available alternatives with the intention of inspecting the selected cable during the earliest available s
.N dMh l It 9110080372 910927 PDR ADOCK 05000277
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O PDR
Dsc,ument Control Desk September 27, 1991 PBAP'S, Units 2 and 3 Page 2 Follow-Up Actions Related to Cable Insulation Failures equipment or system outage. We will keep the Senior Resident Inrpector informed of our specific plans and ections.
If you have any questfoi.. nr require additional information, please do not hesitate to contact 'as.
Very truly yourn,
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Martin, Administrator, Pegion I, USNRC J.
J.
Lyash, USNRC Senfor Resident Inspector, PBAPS
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