05000267/LER-1982-015, Forwards LER 82-015/03L-0.Detailed Event Analysis Encl

Forwards LER 82-015/03L-0.Detailed Event Analysis Encl

ML20053A323
Person / Time
Site:	Fort Saint Vrain
Issue date:	05/18/1982
From:	Warembourg D PUBLIC SERVICE CO. OF COLORADO
To:	Jay Collins NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20053A324	List: 05000267/LER-1982-015, Forwards LER 82-015/03L-0.Detailed Event Analysis Encl 05000267/LER-1982-015-03, /03L-0:on 820418 & 19,w/plant Operating at Power, Emergency Feedwater to Loop 2 Circulator Water Turbine Drives Were Isolated to Repair PV-21244 & PV-21244-1.Caused by Normal Wear,Resulting in Excessive Flow
References
P-82150, NUDOCS 8205250210
Download: ML20053A323 (5)

LER-1982-015, Forwards LER 82-015/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
2671982015R00 - NRC Website

text

Public Service Compamy Cf Oderade K

16805 Road 19 1/2, Platteville, Colorado 80651-9298 May 18, 1982 Fort St. Vrain Unit No. 1

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MAY 211982 Mr. John T. Collins, Regional Administrator LL J

Region IV Nuclear Regulatory Commission 611 Ryan Plaza Drive Suite 1000 Arlington, Texas 76011

Reference:

Facility Operating License No. DPR-34

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Docket No. 50-267

Dear Mr. Collins:

Enclosed please find a copy of Reportable Occurrence Report No. 50-267/82-015, Final, submitted 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. 50-267/82-015.

Very truly yours, WW&

Don Warembourg C/

Manager, Nuclear Production DW/cls Enclosure g

cc:

Director, MIPC 3

8205250210 820518

//f PDR ADOCK 05000267 S

PDR

REPORT DATE:

May 18, 1982 REPORTABLE OCCURRENCE 82-015 ISSUE O CCCURRENCE DATE:

Aoril 18, 1982 Page 1 of 4 FORT ST. VRAIN NUCLEAR GENERATING STATICN PUBLIC SERVICE COMPANY OF COLORADO 16805 WELD COUNTY ROAD 19 1/2 PLATTEVILLE, COLORADO 80651-9298 REPORT NO. 50-267/82-015/03-L-0 Final IDENTIFICATION OF OCCURRENCE:

On two separate occasions, the emergency feedwater supply to Loop 2 helium circulators was isolated. These events constitute a degraded mode allowed by LCO 4.2.2.a and are reportable per Fort St. Vrain Technical Specification AC 7.5.2(b)2.

EVENT

DESCRIPTION

On April 18, 1982, and again on April 19, 1982, erratic operation of PV-21244 and PV-21244-1 necessitated isolation of the emergency feedwater to Loop 2 helium circulator water turbine drives.

Fort St.

Vrain Technical Specification LC0 4.2.2.a specifies that a supply of energancy feedwater be available to drive the circulator water turbines and further allows for isolation of the emergency feedwater supplu for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, without the affected circulators being considerec inoperable.

Refer to Figure 1 for a simplified diagram of this system. A pressure control system is provided to control emergency feedwater flow to eac of the circulator pelton wheel supply conditions $)and headers,(

unAer flow, and no flow conditions. Under flow PV-21 4 U1 controls supply header pressure. Under no flow conditions, PV-21244-1 (2) is provided to relieve excess header pressure to the turbine water drain tank in the event PV-21244 leaks through.

Event 1 On April 18, 1982, at 0945 hours0.0109 days <br />0.263 hours <br />0.00156 weeks <br />3.595725e-4 months <br />, with the plant operating at 28%

thermal power, emergency feedwater was isolated ahead of PV-21244 to repair PV-21244-1.

Emergency feedwater was restored at 1505 hours0.0174 days <br />0.418 hours <br />0.00249 weeks <br />5.726525e-4 months <br /> on April 18, 1982, 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 restoring the require.ents of circulator operability.

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REPORTABLE OCCURRENCE 82-015 ISSUE O Page 2 of 4 Event 2 On April 19, 1982, at 0800 hours0.00926 days <br />0.222 hours <br />0.00132 weeks <br />3.044e-4 months <br />, with the plant operating at 287.

thermal power, emergency feedwater was isolated to repair PV-21244.

The valve was repaired and calibrated.

Emergency feedwater was restored at 1600 hours0.0185 days <br />0.444 hours <br />0.00265 weeks <br />6.088e-4 months <br /> on April 19, 1982, 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.

This restored the requirements of circulator operability. If necessary, the affected he'li um circulators could have been operated on water turbine drive at reduced speed utilizing the water supply from the emergency condensate or firewater systems.

CAUSE

DESCRIPTION:

Excessive flow through PV-21244 and PV-21244-1 necessitated manual isolation of the emergency feedwater header to Loop 2 circulators to effect rerairs.

CORRECTIVE ACTION:

Event 1 Replaced disk and stem, gaskets, and packing set on PV-21244-1, and the system was returned to service.

Event 2 Replaced valve internals, bonnet gasket, gasket seal, and calibrated PV-21244. System returned to service.

No further corrective action is anticipated or required.

=

REPORTABLE OCCURRENCE 82-015 ISSUE O Page 3 of 4 To Backup Bearing Emergency y

p Feedwater Water Header y

c PV-21243 To Loop 1 Helium Ng Id4 Circulator Water p

kN Turbine Drives o

PV-21243-1 To Turbine Water Drain Tank Y

O PV-21244 To Loop 2 Helium Ni Circulator Water m

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L Turbine Drives 1

l c PV-21244-1

• To Turbine Water Drain Tank l

EMERGENCY FEEDWATER PRESSURE CONTROL FIGURE 1 i

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REPORTABLE OCCURRENCE 82-015 ISSUE O Page 4 of A Prepared By:

N_

Robert A. Dickerson Technical Services Technician i

Reviewed By:

, /k Charles Fuller ~

Technical Services Engi eering Supervisor Reviewed By:

M Edwin t).'LHilf' Station Manager Approved By:

Wd Don Warembourg

/

Manager, Nuclear ProductioW j

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