ML19321A511

Forwards LER 80-032/03L-0

ML19321A511
Person / Time
Site:	Fort Saint Vrain
Issue date:	07/15/1980
From:	Warembourg D PUBLIC SERVICE CO. OF COLORADO
To:	Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML19321A512	List: ML19321A511 ML19321A523
References
P-80212, NUDOCS 8007230543
Download: ML19321A511 (5)

Text

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16805 ROAD 19%

_'u J PLATTEVILLE, COLOR ADO 80651 July 15, 1980 Fort St. Vrain Unit No. 1 P-80212 Mr. Karl V. Seyfrit, Director Nuclear Regulatory Comission Region IV Office of Inspection and Enforcement 611 Ryan Plaza Drive Suite 1000 Arlington, Texas 76012

Reference:

Facility Operating License No. DPR-34 Docket No. 50-267 Denr Mr. Seyfrit:

Enclosed please find a copy of Reportable Occurrence Report No. 50-267/

80-32, Final, subtaitted per the requirements of Technical Specification AC 7.5.2(b) 2.

Also, please find enclosed one copy of the Licensee Event Report for Reportable Occurrence Report No. 50-267/80-32.

Very truly yours, Ww Don Wa a.nbourg #

Manager, Nuclear Production DW/cis Enclosure cc: Director, MIPC I

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8007230 5Y3 S

REPORT DATE: July 15, 1980 REPORTABLE OCCURRENCE 80-32 ISSUE O OCCURRENCd DATE: June 17, 1980 Page 1 of 4 FORT ST. VRAIN NUCLEAR GENERATING STATION PUBLIC SERVICE COMPANY OF COLORADO 16805 WELD COUNTY ROAD 19 1/2 PLATTEVILLE, COLORADO 80651 REPORT NO. 50-267/80-32/03-L-0 Final IDENTIFICATION OF OCCURRENCE:

On June 17 and 18, 1980, the plant was operated at power with emergency feed-water header supply to Loop 1 helium circulator water turbine drives isolated.

This constitutes operation in a degraded mode of LCO 4.2.2(a), and is re-portable er Fort St. Vrain Technical Specification AC 7.5.2(b)2.

EVENT DESCRIPTION:

I June 15, 1980, with the plane aperating at approximately 68% thermal I reser and 193 MWe, a Plant Trou'le Report was initiated stating that PV-21243 was not controlling at the appropriate setpoint. This problem did not render the emergency feedwater header supply to Loop 1 circulators inoperable.

Re to Fi ure 1. The Loop 1 pressure control system consists of two valves C and 2 ). . MainpressurecontrolvalvePV-21243(( of Figure 1) is de gnedtocontrolfeedwatersupplypressureunderflowc{o)ditions. n Secon-dary valve PV-21243-1 c O2 of Figure 1) is provided to bleed off leakage from the main valve to the turbine water drain tank under the no-flow con- l dicions which normally exist.

Preparations were being made to isolate the Loop 1 emergency feedwater header l on June 17, 1980, for repair of a line leak; and PV-21243 was to be repaired at the same time. Fort St. Vrain Technical Specification LCO 4.2.2(a) pro-vides that the emergency feedwater header may be isolated for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> with the reactor at power without the helium circulators being considered inoperable. Prior to isolating the system on June 17, a loop shutdown resulted in a reactor power reduction to less than 2%.

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REPORTABLE OCCURRENCE 80-32 ISSUE O Page 2 of 4 EVENT DESCRIPTION: (Cont'd)

The Loop 1 emergency feedwater header supply was isolated via V-211615

( of Figure 1) at 0830 hours0.00961 days <br />0.231 hours <br />0.00137 weeks <br />3.15815e-4 months <br /> on June 17 for repair of the problems noted abo (}ve). Because the reactor was not at power, no LCO 4.2.2 degraded operation occurred. e Howev'r, by 2115 hours0.0245 days <br />0.588 hours <br />0.0035 weeks <br />8.047575e-4 months <br /> all preparations for return to power operation had been completed, and reactor power was increased to greater than 2%. Because PV-21243 repair was not complete, the Loop 1 s emergency feedwater supply was still isolated. This consitutes operation in a degraded mode of 100 4.2.2(a) .

By 1500 hours0.0174 days <br />0.417 hours <br />0.00248 weeks <br />5.7075e-4 months <br /> on June 18, 1980, repair work had been completed. The system was returned to service within the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> allowed by LCO 4.2.2(a), thus meeting the requirements for circulator operability.

Had it been necessary during this period of degraded mode operation, the Loop 1 circulators could have been, operated on water turbine drive utilizing a water supply from the emergency condensate or firewater systems.

CAUSE DESCRIPTION:

Operation in LCO 4.2.2 degraded mode was the result of a return to reactor power operation with emergency feedwater header supply to Loop 1 circulators isolated.

System isolation was necessary to replace a leaking elbow on the 1" line downstream of PV-21243-1 and to repair PV-21243 to alleviate valve leakage.

At the time the reactor was returned to power operation, the repair of PV-21243 was not complete; thus the system was still isolated.

CORRECTIVE ACTION:

Problems with pressure control and leakage on PV-21243 were alleviated by applying devcon to the area under the seal ring gasket.

Valve repair was completed on June 18, 1980, and the system returned to service.

No further corrective action is anticipated or required.

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FIGilRE 1 4

Loep 1 Energency Feedwater Pressure Control Emergency Feedwater lleader To Backup i Bearing Water b To Loop 1 llelium V-211615 1 PV-21243 Circulator Water Turbine Drives

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a 2 PV-21243-1 V R > To Turbine Water Drain Tank E U10 oo u> m

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.l REPORTABLE OCCURRENCE 80-32 ISSUE O Page 4 of 4 Prepared By: - .

Cathy Qy Hirsch Technical Services Technician  ;

1 Reviewed By: .

f'J. Mahm

/TeclnicalServicesSupervisor Reviewed By:

Frank M. Mathie Operations Manager Approved By: m f7 _

Don Warembourg //

Manager, Nuclear Production O