PY-CEI-NRR-2208, Special Rept Re Inoperable Post Accident Monitoring Instrumentation.Efforts in Progress to Restore Instrumentation as Soon as Possible,But No Later than End of Upcoming Refueling Outage Scheduled to Begin 970912

Special Rept Re Inoperable Post Accident Monitoring Instrumentation.Efforts in Progress to Restore Instrumentation as Soon as Possible,But No Later than End of Upcoming Refueling Outage Scheduled to Begin 970912

ML20217Q226
Person / Time
Site:	Perry
Issue date:	08/26/1997
From:	Myers L CENTERIOR ENERGY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
PY-CEI-NRR-2208, NUDOCS 9709020120
Download: ML20217Q226 (2)

Text

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49mm P6wer Generation Group Perry Nuclear Power Plant Mad Address: 21&28H916 Low W. Myert 10 CoNw Road P.o. Don 97 FAX: 216-280 8029 We President

. Perry,oNo 44061 Perry. oH 44081 :

August 26,1997 PY-CEl/NRR 2208L United States Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Perry Nuclear Power Plant Docket No. 50-440 Special Report - Inoperable Post Accident Monitoring Instrumentation Ladies and Gentlemen:

In accordance with the provisions of Perry Nuclear Power Plant Technical Specification 3.3.3.1, the -

enclosed Special Report is being submitted to notify the Nuclear Regulatory Commission of an inoperable channel of Post Accident Monitoring instrumentation. Efforts are in progress to restore the instrumentation as soon as pcssible, but no later than the end of the upcoming refueling outage scheduled to begin September 12,1997, If you have questions or require additional information, please contact Mr. Henry L. Hegrat,

• Manager - Regulatory Affairs, at (216) 280-5606.

Very truly yours, O .44 0 Enclosure g g]'I cc: NRC Region 111 Administrator NRC Resident Inspector NRC Project Manager

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9709020120 970826 PDR ADOCK 05000440 S PDR b f k h, l l l

o PY CEl/NRR 2208L Enclocure Page1ofI SPECIAL REPORT INOPERABLE POST ACCIDENT MONITORING INSTRUMENTATION The primary purpose of the Perry Nuclear Power Plant (PNPP) Post Accident Monitoring instrumentation is to display plant variables required to be monitored by the control room operators during accident scenarios.

The Primary Containment /Drywell Area Gross Gamma Radiation monitors, which comprise a portion of the Post Accident Radiation Monitoring system instruments, are provided to monitor for potential sigt.incant radiation releases, and to aid in the assessment of any such releases for determining site emergency action levels. PNPP has two multichannel area radiation monitors manufactured by Kamen Instrumentation Corporation, each consisting of one high range containment detector and one high range drywell detector.

One channel of t..e Primary Containment /Drywell Area Gross Gamma Radiation monitors has been inoperable for greater than the allowed outage time permitted by Technical Specifications (TS).

Troubleshooting is currently in progress to determine and correct the root cause of the inoperability. In accordance with TS 3.3.3.1 Action B.1, if the required channel is not restored within 30 days, a Special Report is required to be submitted detailing root cause determination of the inoperable channel and proposed restorative actions. The TS Bases indicate the Special Report shall be submitted within 14 days.

Accordirc;ly, this Special Report is being submitted to comply with TS Action B.l.

Channel inoperability for Containment Channel 2 for the Division 1 Containment Area monitor was identified by an upscale reading indication on the associated recorder. The associated channel in the i Division 2 monitor did not reflect a similar increase and area surveys indicated no change in area radiation levels. Troubleshooting has focused on determining the direct cause of the problem (i.e., detector, cable, or monitor process unit). Disassembly and cleaning of the containment connections prior to the mineral-insulated cable junction appeared to reduce the magnitude of the indication, but have not been sufficient to restore the monitor to an operable status. To date, troubleshooting efforts indicate the problem to be the signal conductor resistance at the containment penetration which may require replacement or rework of the penetration conductor. liowever, insufficient data has been obtained to conclusively attribute the failure to the conductor. Consequently, further troubleshooting efforts are required and are being expedited in accordance with the PNPP work prioritization program.

Radiation monitoring of the containment atmosphere has been adequately maintained during this time via the atmosphere radiation and area radiation monitors. Based on the preliminary results of troubleshooting efforts, it is expected that in the event of an accident, the monitor will reflect increases in the containment area radiation, and therefore, will likely perform its safety function. However, the monitor will indicate higher than actual radiation levels. As a result, the monitor was conservatively declared inoperable in accordance with TS requirements.

Based on the results of ongoing troubleshooting efforts, which are expected to be complete by August 31,1997, appropriate repairs will be initiated. If unforeseen problems arise which delay restoration, the instrumentation will be replaced or made operable during the upcoming refueling outage scheduled to begin on September 12,1997.

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