ML20235Q966
| ML20235Q966 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 02/23/1989 |
| From: | Shawn Smith TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 89-02, 89-2, NUDOCS 8903030095 | |
| Download: ML20235Q966 (3) | |
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1 TENNESSEE VALLEY AUTHORITY Sequoyah Nuclear Plant Post Office Box 2000 l
Soddy-Daisy, Tennessee 37379 February 23, 1989 U. S. Nuclear Regulatory Coinmission Document Control Desk Washington, DC 20555 Gentlemen:
i TENNESSEE VALLEY AUTHORITY - SEQUOYAH NUCLEAR PLANT UNIT 2 - DOCKET NO.
50-328 - FACILITY OPERATING LICENSE DPR SPECIAL REPORT 89-02 The enclosed special report provides details concerning fire barrier being nonfunctional for greater than seven days.
This event is reported in accordance with action statement (a) of Limiting Conditions for Operation (LCO) 3.7.12.
Very truly yours, l
TENNESSEE VALLEY AUTHORITY l' 'A S. 4. e Sinith '
Plant Hanager Enclosure l
cc (Enclosure):
J. Nelson Crace, Regional Administrator U. S. Nuclear Regulatory Commission Suite 2900 101 Marietta Street, NW Atlanta, Georgia 30323 Records Center Institute of Nuclear Power Operations Suite 1500 1100 circle 75 Parkway Atlanta, Georgia 30339 NRC Inspector, Sequoyah Nuclear Plant 8903030093 890223 4
PDR ADOCK O'.5000328 l\\
c.
PDC An Eaual Opportunity Employer e_-_-__________
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SEQUOYAH NUCLEAR PLANT UNIT 2 SPECIAL REPORT 89-02 DESCRIPTION OF EVENT On January 28, 1989 with unit 2 in mode 5 (0 percent power, 0 psig, 113 degrees F) a fire barrier (shield building wall, between 685 foot elevation and 711 foot elevation and azimuth 280 degrees and 301 degrees) was nonfunctional for an interval greater than seven days.
On January 21, 1989, within the area of the above specified shield building wall section, twelve mechanical penetration seals of various sizes, (4 inch diameter to 12 inch diameter) were removed in accordance with Workplan (WP) 7095-01.
Removal of the seal material from the penetrations resulted in the fire barrier being nonfunctional and as required by Limiting condition for l
Operation (LCO) 3.7.12, an hourly firewatch was established within one hour l
and was maintained until the penetrations were restored to functional status on February 16, 1989.
Thus, the fire barrier was nonfunctional for 25 days. Action statement (a) of the LCO requires sabmittal of a special report if the fire barrier remains nonfunctional for greater than seven days. Modifications to the shield building mechanical penetration seals are being performed to fullfill commitments to NRC (refer to LER 50-327/87040).
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The Modifications activities are continuing and a potential for more shield building penetrations to not be complete within seven days does exist.
In such instances notification to the NRC will be made as appropriate.
l CAUSE OF EVENT The shield building mechanical penetration seal material emits ester hydrocarbon during the curing process.
Ester hydrocarbon particles impacts efficiency of charcoal filters of various air cleanup systems.
(Such as, i
emergency gas treatment, auxiliary building gas treatment, containment purgo air). Therefore, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to operating an air clean up system, (containment purge air) mechanical penetration seals activities were suspended. The suspension of the penetration seal activities occurred several times after the old seals were removed.
As a result, the fire barrier was not returned to the functional status within seven days.
ANALYSIS OF EVENT l
This event is being reported in accordance with the requirements of action statement (a) of LCO 3.7.12.
A roving firewatch was established to inspect the affected area of the shield building wall on an hourly basis as required by the action statement of LCO 3.7.12.
The existing fire detection and fire suppression systems for l
the affected area (in the annulus) are operable and would have activated in the event of a fire. Therefore, there was no danger to safety-related equipment.
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' CORRECTIVE ACTION A roving firewatch at a regular interval of one hour was established and was maintained until the shield building mechanical penetration seals were restored to functional status on February 16, 1989. No further action is required.
ADDITIONAL INFORMATION j
Refer to LER 327/87040, " Reactor Shield Building Mechanical Penetration Seals Not Qualified to Ensure Compliance With the Design Basis Due to Design Deficiencies."
COMMITMENTS None.
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