ML18219C346

06/11/1976 Letter Re LER 1976-002-00: Violation of Appendix B Technical Specifications Section 2.1.1.2(i)

ML18219C346
Person / Time
Site:	Cook
Issue date:	06/11/1976
From:	Jurgensen R American Electric Power Service Corp, Indiana Michigan Power Co, (Formerly Indiana & Michigan Power Co)
To:	James Keppler NRC/IE, NRC/RGN-III
References
LER 1976-002-00
Download: ML18219C346 (4)

Text

~ plcefl INDIANA8 MICHIGANPOSER COMPANY DONALD C. COOK NUCLEAR PLANT P.O. Box 458, Bridgman, Michigan 49106 June ll, 1976 Mr. J.G. Keppler, Regional Director Office of Inspection and Enforcement United States Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, IL 60137 Operating License DPR-58 Docket No. 50-315 AEO No. 50-315/76-02

Dear Mr. Keppler:

On June 7, 1976, we reported that condenser AT had been between 23oF and 24.25oF for approximately 4.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> in violation of Appendix B Technical Specifications Section 2. l. 1.2(i). This event actually occurred on May 19, 1976, but at the time of the event it was believed that condenser AT had not exceeded the Technical Specification limit and, therefore, did not require reporting. Subsequent investigation revealed that a report would be required.

While operating at 75'A reactor power the circulating water pumps discharge pressure was 3.1 psig and the flow rate was 602,000 gpm with two circulating water pumps running. At the time the temperature rise as calculated from the indicated temperatures was 19.5of. However, the electronic average as indicated on the recorder and which also gives the hT alarm function was indicating 16.6oF.

At this time the circulating water system condenser discharge valves were throttled to lower the flow rate. The flow rate was lowered to 508,000 gpm and circulating water pumps discharge pressure of 7.5 psig.

The aT at this time as calculated from the indicated temperatures was 24.25oF. The electronic average at this time indicated 20.8oF and no alarm was received. The a,T remained between 23.1oF and 23.6oF for four and a half hours. For the next four hours the hT was between 22.0oF and 23.0oF. At this time the circulating water system condenser discharge valves were opened to increase the flow rate and the hT was brought down to 20.0oF.

Investigation revealed that the inlet thermocouples for the average circuit had wet junctions which caused the indicated average to read out in error. The junctions were dried out and coated with varnish to prevent their getting wet in the future.

V P'

'I

, r.

~ J.G. Keppler

~

June 11, 1976 Page 2 The average hT over the four and a half hours as calculated from the inlet and outlet temperature indications was 23.6oF and the maximum was 24.25oF. Surveillance of the lake environment as described in Appendix B, Technical Specifications Section 4. 1.2. 1 has shown no adverse effects to the aquatic biota.

Sincerely,

.W. Jur s Plant M nager

/bab cc: R.S. Hunter J.E. Dolan G.E. Lien R. Kilburn R.J. Vollen BPI R.C. Callen MPSC K.R. Baker RO:III P.W. Steketee, Esq.

R. Walsh, Esq.

G. Charnoff, Esq.

G. Olson J.M. Hennigan PNSRC R.S. Keith Dir., IE (20 copies)

Dir., MIPC (2 copies)

Dir., Licensing (1 copy)

T.A. Kriesel