ML19259A732

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Responds to DA Beckman 781220 Request Re Containment Type a Leak Test.Test Was Performed During Nov 1978.After Start of Initial Containment Pressurization,Personnel Air Lock Was Found at Same Pressure as Containment (Leaking Solenoids)
ML19259A732
Person / Time
Site: Beaver Valley
Issue date: 01/03/1979
From: Werling J
DUQUESNE LIGHT CO.
To: Grier B
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
BVPS:JAW:620, NUDOCS 7901100228
Download: ML19259A732 (4)


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Beaver Llley Power Staticin, Unf.:Jo. 1 Docket No. 50-33'.. License No. R R-6o Containment Type "A" igak Test Mr. B. H. Grier, Directcr of Regulation United States Muclear Regulatory Commission Region 1 .

631 Park Avenue King of Prussia, Pennsylvania 19406

Dear Mr. Grier:

The following report is submitted in response ta the request L--

D. A. Beckcan on Dececher 20, 1978.

The Containment Type A Lesk Test was perforced at Beaver Valle'y3wn Station during November, 1978. This report L provided as a discussion of significant events which occurred during the perfor=ance of the test. Vore detailed information vill be presented in the 90 day test report.

Shortly after the start of initial pressurization of the contain=ent, the personnel air lock was found pressurized to the same pressure as the containment (approxicately 2 psig). Although the air lock was pres 3urized, the outer door co as nct leekir.g. ~'ha scicr.cid cperated eque112.1 3 misus vu u. e ~ ~. . lud. .e.c found to be lecking by from the containcent into the air lock. A codification was cade to the equalizing line vent to provide canual isolation. 7:is canual isolation valve vill be nor= ally closed during operation. except for containment entries, to ensure containment integrity.

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Mr. B. H. Grier January 3, 1979 .o 3 BVPS: JAW:620 Page 2 After pressurization of the containment was completed and measurement of the Type A leakage begun, significant temperature changes between data points were observed (approximately 0.3 - 0.4*F). Corresponding pressur( changes in the containment were not observed and, thus, sizable data scatter for the calculated mass points were obtained. This data scatter made analysis of the actual leak rate difficult. Leak teams were dispatched to check all possible sources of air leakage from the containment. Several minor leaks were discovered and isolated or corrected. The containment air ejector outside isolation valve (butterfly valve) was found positioned past its closed position and was realigned.

The LHSI lines which had been drained and vented for the test were refilled. A second containment recirculation air fan which had experienced higher than normal vibration and been shutdown early in the test was started in an attempt to provide better air r circulation to improve temperature data collection, but the temperature variations continued.

Data was collected for an additional 41 hours4.74537e-4 days <br />0.0114 hours <br />6.779101e-5 weeks <br />1.56005e-5 months <br />. A leak rate of 0.074%/ day was obtained from a least squares fit of all o'f the 41 hourly mass points. Per JBVPS Technical Specifications, allowable leakage is 0.075%/ day.

A supplemental test was then performed to check the validity of the data obtained. Both a one-hour pump back test and an eight-hour superimposed calibrated leak test were performed. Both tests failed to meet the required 0.25 La tolerance established as acceptance criteria for these taa*a The temperature scatter problems were deterrined to be caused by insufficient resolution of the temperature detectors by the computer. It was decided to depressurize the containment and attempt to locate any additional leakage during the correction of the instrumentation problems.

The following work was done prior to repressurizing the containment:

1. A Type C test was attempted on the containment air ejector penetration isolation valves since the seated position of the valves was questionable and the air ejector had been used as an artificial lond for tbn servica boiler, ennsing eba panatration to become quite hot. Neither isolation valve was capable of being pressurized with the Type C test equipment due to excessive leakage.

The rubber valve seats on both valves were found damaged and the manual operator on the inner valve stripped. The valves were repaired and Type C tested successfully. The air ejector penetration isolation valves had been successfully Type C-tested earlier in the outage. Operating procedures have been revised to prohibit use of the containment air ejector as an artific.ial load for the service boiler.

Mr. B. H. Glier January 3, 1979 . ,

BVPS: JAW:620 Page 3

2. RTD bridges used for sensing containment air. temperatures were modified. The milli-volt output per degree temperature (MV/*F) .

was increased by a factor of ten to reduce the effect of any computer hardware fluctuations and to improve the repeatability of the temperature measurement.

3. The main steam lines up to the main steam isolation valves and the steam generators were pressurized to approximately 25 psig and a leak check performed using a sonic leak detector. Several packing leaks and one fitting leak were located. The valves were repacked and the fitting leak repaired. In addition, the steam generator manways were retorqued.
4. The High Head Safety Injection lines and the Reactor Coolant Pump seal injection and leakoff lines, which were drained and vented for the Type A test, were refilled. -

Following completion of the above work, the containment was repressurized and the total integrated leak rate determined to be 0.0348%/ day at a 95%

confidence level of 0.0058%/ day. The superirposed calibrated leak method was used as the supplemental test and verified the accuracy of the Type A test instrumentation well within the required 0.25 La.

Very truly yours, I

J.A.Werlingh Superintendent e

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Mr. B. H. Grier January 3,1979 , ,

BVPS: JAW:620 Page 4 -

cc: Director'Of Management & Program Analysisy/ _

United States Nuclear Regulatory Commission _

Washington, D. C. 20555 D. L. Wigginton, BVPS Licensing Project Manager United States Nuclear Regulatory Conmission Washington, D. C. 20555 D. A. Beckman, Nuclear Regulatory Co==ission, King of Prussia, PA G. A. 01 con, Secretary, Price Movers Committee - EFI e

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