ML20071M867

Interim Deficiency Rept Re Min Separation Requirements for Certain Components of 4,160-volt Switchgear.Initially Reported on 811002.Requests 90-day Extension to Complete Investigation of Cable Termination Practices & File Rept

ML20071M867
Person / Time
Site:	Clinton
Issue date:	09/17/1982
From:	Gerstner W ILLINOIS POWER CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
10CFR-050.55E, 10CFR-50.55E, U-0535, U-535, NUDOCS 8209270265
Download: ML20071M867 (3)

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/LLINDIS POWER 00MPANY U-0535 CLINTON POWER STATION. P.O. BOX 678. CLINTON. ILLINOIS 61727 September 17, 1982 Mr. James G. Keppler Director, Region III Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137

Dear Mr. Keppler:

Deficiency 81-05 10 CFR 50.55(e)

Minimum Separation Requirements for Certain Components of the 4160V Switchgear On October 2, 1981, Illinois Power verbally notified Mr. H.M.

Wescott, NRC Region III, of a potential reportable deficiency per 10CFR50.55(e) concerning minimum separation requirements for certain components of the 4160V switchgear. This initial notification was followed by three interim reports: L.J. Koch letter U-0326 to J.G.

Keppler dated November 6, 1981, W.C. Gerstner letter U-0423 to J.G.

Keppler dated February 26, 1982, and W.C. Gerstner letter U-0490 to J.G. Keppler dated May 27, 1982. Our investigation of this matter has not been completed, and this letter provides an update on our investigation.

BACKGROUND During September, 1981, three nonconformance reports (NCRs 5425, 5426, 5453) were written against the 4160V switchgear, addressing apparent violation of separation requirements between Class 1E and Non-Class lE circuits inside certain switchgear cubicles. These violations were identified subsequent to termination of field cables and were found to exist in both current transformer circuits and control wiring circuits. This lack of physical separation in the installed switchgear prompted the investigation into several areas of potential deficiency, including design, construction procedures and controls, and QC training.

INVESTIGATION RESULTS (INTERIM)

In the area of design, Sargent and Lundy (CPS Architect Engi-neer) was requested to review their design and procedures in meeting the requirements of the Clinton Power Station FSAR. This review determined that drawings for the subject 1E equipment did not meet separation requirements described in IEEE 384. However, Sargent and 8209270265 820917 so%S PDR ADOCK 05000461 SL' S PDR

'J .G. . Kcppler. Sep tember 17, 1982 NRC Page 2 of 3 Lundy performed a comprehensive technical analysis of the subject lE equipment which demonstrated that the safety function of the class 1E switchgear is not compromised. Sargent and Lundy also performed a i

100% review of their wiring diagrams to determine if other equipment might not meet the separation requirements of the Clinton Power Station FSAR. The results of their review showed no-other equipment drawings required revision.

In the area of construction procedures and controls, and QC training, investigation has revealed that present procedures for cable termination and inspection are inadequate to assure and verify that_ required separation is maintained. The governing contractor (Baldwin Associates) procedures, BAP 3.3.3 and Quality Control Instruction 408, require inspection of class IE cable terminations for separation considerations, but do not require inspection of non-class 1E cable terminations within IE panels. If non-1E cables are terminated in a class 1E panel or enclosure after all class lE cables have been terminated and inspected,-an inspection to verify separation is not required.

Presently, these procedures / instructions are being reviewed and evaluated for additional separation controls in conjunction with .an Electrical Stop Work Recovery Program being prepared at CPS, under close scrutiny by the NRC. Revised procedures / instructions will be issued to assure that separation requirements between class lE and non-1E cables terminated within electrical equipment are met.

Additionally, a reinspection effort is being planned to assure that separation requirements are met for Class lE cables previously terminated and inspected.

SUM 4ARY The ' conditions noted in the three (3) nonconformance reports have been fully evaluated from an engineering standpoint and determined not to have a significant adverse affect on the safety of operations. However, since procedures which control inspection of terminations of both class 1E and non IE cables within class 1E panels are not adequate to assure that separation requirements are met, a reinspection effort must be performed to determine and assure that existing completed work meets separation requirements. Until

! reinspection plans have been developed and implemented, and results i of which evaluated for significance, a conclusion as to reportability

! cannot be made. We anticipate that we will need an extention of

! approximately ninety (90) days to complete our investigation of cable termination practices, provide a determination of reportability of the potential deficiency, and to file the final report.

Very truly yours N'

W.C. Gers,tner Executive Vice President ,

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'J.G. Keppler Sep tember 17, 1982 11RC Page 3 of 3 cc: 11.11. Livermore, tiRC Resident Inspector Director, Office of I&E, Washington, D.C.

Illinois Department of fluclear Safety Director-Quality Assurance