United States Nuclear Regulatory Commission - Protecting People and the Environment

ACCESSION #: 9905050003

Illinois Power Company
P.O. Box 678
Clinton, IL 61727
Tel 217 935-8881 x3900
Fax 217 935-4632
Chief Nuclear Officer
An Illinova Company
April 30, 1999
Docket No. 50-461 10CFR21.21
Document Control Desk
Nuclear Regulatory Commission
Washington, D. C. 20555
Subject: 10CFR21 Final Report 21-99-003: Deficiency in Commercial Grade Dedication Process Used by Circuit Breaker Refurbishment Supplier Trentec

Dear Madam or Sir:

Clinton Power Station (CPS) notified the NRC in a letter dated March 12, 1999, that an evaluation under the provisions of 10CFR, Part 21, was not complete for a deficiency identified in the commercial grade dedication process used by circuit breaker refurbishment supplier Trentec. The evaluation is now complete and this letter provides the final report on this issue. CPS has concluded that this issue is not reportable under the rule.

On January 15, 1999, the CPS Quality Assurance (QA) Department identified that the commercial grade dedication process used by Trentec for Westinghouse circuit breaker (1AP05EH) serial number 01YN002 B2 SER 1 did not ensure its design configuration was maintained. QA personnel identified this issue during a surveillance of Trentec.

Trentec had purchased a commercial grade Ratchet and Cam Assembly from the original equipment manufacturer and dedicated it for use in a safety-related Westinghouse circuit breaker. Trentec disassembled the Ratchet and Cam Assembly, verified critical characteristics and reassembled the unit.

However, the process did not ensure the unit was reassembled to the configuration that it was purchased, nor did it verify like-for-like characteristics of spacers and the ratchet wheel thickness within the assembly. The circuit breaker with the potentially deficient unit was thoroughly tested at the Trentec facility and at CPS prior to installation. At the time the deficiency was discovered, the circuit breaker was installed at the Unit Auxiliary Transformer 1B Feed to 6.9 kilovolt Bus 1B. To determine the impact of the deficiency on the installed breaker, the breaker needed to be removed from its cubicle and inspected. Plant conditions at that time prohibited removing the breaker.

U-603204 Page 2

The investigation determined that this circuit breaker was the only CPS breaker having this concern. Condition Report 1-99-01-136 was initiated to track investigation and resolution of this issue.

CPS has now completed qualification testing of a prototype breaker with acceptable results. In addition, the installed breaker has been inspected and the Ratchet and Cam Assembly was found to be in accordance with the design configuration. Based on the acceptable completion of these activities, the evaluation of this issue concludes that the installed breaker is acceptable and this issue is not reportable under the provisions of 10CFR, Part 21.

Additional information about this issue may be obtained by contacting R. D. Weber, Procurement Engineering, at (217) 935-8881, extension 3785.

Sincerely yours,

John P. McElwain
Chief Nuclear Officer


cc: NRC Clinton Licensing Project Manager
NRC Resident Office, V-690
Regional Administrator, Region III, USNRC
Illinois Department of Nuclear Safety
INPO Records Center

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