05000369/LER-1981-029, Forwards LER 81-029/03L-0.Detailed Event Analysis Encl

Forwards LER 81-029/03L-0.Detailed Event Analysis Encl

ML20005A000
Person / Time
Site:	McGuire
Issue date:	04/08/1981
From:	Parker W DUKE POWER CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20005A001	List: 05000369/LER-1981-029, Forwards LER 81-029/03L-0.Detailed Event Analysis Encl 05000369/LER-1981-029-03, /03L-0:on 810310,during Routine Insp,Flow Meter for Conventional Waste Water Treatment Discharge Line Was Not Operating Properly.Caused by Improper Setting of Select Switch.Flow Terminated & Select Switch Properly Set
References
NUDOCS 8106290237
Download: ML20005A000 (3)

LER-1981-029, Forwards LER 81-029/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
3691981029R00 - NRC Website

text

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DUKE POWER COMPANY Powsm Buttonwo 422 Sourn Caumen Snzzr, Caantorre, N. C. asa4a

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3 7 3..o s 3 Mr. James P. O'Reilly, Director U. S. Nuclear Regulatory Connaission Region II 101 Marietta Street, Suite 3100 Atlanta, Jeorgia 30303 Re: McGuire Nuclear Station Unit 1 Docket No. 50-369

Dear Mr. O'Reilly:

Please find attached Reportable Occurrence Report R0-369/81-29. This report concerns the flowmeter for the Conet'tional Waste Water discharge line being inoperable. This incident was considered to be of no significance with respect to the health and safety of the public.

Very truly yours, h?% >

William O. Parker, Jr.

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Director Mr. Bill Lava 11ee Office of Management and Program Analysis Nuclear Safety Analysis Center U. S. Nuclear Regulatory Commission P. O. Box 10412 Washington, D. C.

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s DUKE POWER COMPANY MCGUIRE NUCLEAR STATION INCIDENT REPORT Report Number: R0-369/81-29 Report Date: March 26, 1981 Occurrence Date: March 10, 1981 Facility: McGuire Unit 1, Cornelius, North Carolina Identification of Occurrence:

The flow meter for the Conventional Waste (WC) Water Treatment discharge line was declared inoperable.

Condition Prior to Occurrence: Mode 5, Cold Shutdown Description of Occurrence:

A*. 'some time beween 0800 and 0900 hours0.0104 days <br />0.25 hours <br />0.00149 weeks <br />3.4245e-4 months <br /> on March 10, 19'11, Chemistry personnel i

were conducting a daily rcutine checkout of the WC discharge when they noticed the water level of the f.wrshall fiume measuring device did not seem to corre-spond with the flow meter indication. They measured flow using the Head vs Flow table (ISCO Open Channel Flow Measuremen: Handbook) and found out that the flow

- neter was reading approximately 200 GPM higher. At 0830 hours0.00961 days <br />0.231 hours <br />0.00137 weeks <br />3.15815e-4 months <br />, they shut off the WC pump and used gravity flow discharge (180 to 200 GPM). This was reported to their supervisor and he went back to check the instrument. He verified the flow meter was not functioning properly and reported immediately to the Shift Supervisor on duty who in turn declared the system inoperable at 1040 hours0.012 days <br />0.289 hours <br />0.00172 weeks <br />3.9572e-4 months <br />.

Chemistry personnel terminated WC discharge at 1045 hours0.0121 days <br />0.29 hours <br />0.00173 weeks <br />3.976225e-4 months <br />. This incident was reportable pursuant to MNS Technical Specification 3.3.3.8.

Apparent Cause of Occurrence:

The WC discharge flow meter (Model 1870) is designed ta measure and record flow rate or level in conjunction with the type of open channel primary measuring device used (e.g., weir, fiume, etc.).

The meter is capable of monitoring 1 to 4 different channels by selecting the proper MODE position. Level-to-flow rate conversioa'is accomplished by a plug-in Primary Device Characterization Module which is set (programmed) at the factory witn its respective primsry device. The WC discharge

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flow metet was factory set to use only Level / Flow Rate device number 4.

However, i

somebody changed the position of the mode select switch to device number 3 causing the flow w2ter to functica improperly.

l Analysis of Occurrence:

That WC system was discharging approximately 480 GPM the last time it was monitored on March 9, 1981, at 0850 hours0.00984 days <br />0.236 hours <br />0.00141 weeks <br />3.23425e-4 months <br />.- It is unknown at this time sho moved the MODE select switch or when it was moved from position nabar 4 to 3.

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S'fety Evaluation:

a At the time the incident occurred, Chemistry personnel were able to isolate the WC discharge, thus, Chemistry personnel were not required to estimate flow every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. However, if the WC discharge could not have been terminated, flow could have been measured by taking the water elevation of this flume and obtaining flow rcte using Head vs. Flow Table (ISCO Open Channel Flow Measurement Handbook). This type of measurement is used whether discharging through the pump or due to gravity.

Since there is only new fuel on site at this time, the loss of WC system flow indication had no significance with respect to radiation, and the health and safety cf the public were not affected.

Corrective Action

The WC discharge was terminated within five (5) minutes upon discovering that the flow meter was not functioning properly. A work request was initiated and I&E parsonnel repositioned the flow meter's MODE select switch to device number 4.

The equipment was calibrated and tested for proper operation. A padlock was installed on the flow meter cabinet and no one has access to the key except Chemistry personnel.

The WC system was declared operable on March 10, 1981, at 1558 hours0.018 days <br />0.433 hours <br />0.00258 weeks <br />5.92819e-4 months <br />.

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